The Largest Earthquake in the World

The largest earthquake in the world had a magnitude of 9. 5 and took place in Chile. The Valdivia Earthquake, also know as the Great Chilean Earthquake, happened on Sunday, May 22, 1960. It is the largest earthquake currently on record. It occured in the afternoon and the resulting tsunami affected southern Chile, Hawaii, Japan, the Philippines, eastern New Zealand, southeast Australia, and the Aleutian Islands in Alaska. The epicenter of the Valdivia earthquake was near Lumaco, a coastal city with a population of roughly 11,405.Various estimates of the total number of fatalities from the earthquake and tsunamis have been published, with the USGS citing studies with figures of 2,231; 3,000; or 5,700 killed, and another source uses an estimate of 6,000 dead. An estimated cost of 2. 9 to 5. 8 billion in damage. The 1960 Valdivia earthquake was actually just a series of many strong earthquakes from May 21 to June 6,1960. The first was the Concepcion earthquake and the strongest was the Valdivia earthquake. The first Concepcion earthquake was on May 21,1960.Its epicenter was near Curanilahue. The second and third Concepcion earthquakes occurred a few hours apart from each other on May 22. The Valdivia earthquake occurred on May 22. This earthquake affected all of Chile between Talca and Chiloe Island, more than 150,000 sq mi. Most coastal villages disappeared. At Corral, the main port of Valdivia, the water level rose 13 ft before it began to recede. A wave of 26 ft struck the Chilean coast, mainly between Concepcion and Chiloe. Ten minutes later another wave measuring 33 ft was reported.Hundreds of people were already reported dead by the time the tsunami struck. One ship, Canelos, starting at the mouth of Valdivia River sank after being moved 0. 93 mi backward and forward in the river; its mast is still visible today. A number of Spanish-colonial forts were completely destroyed. Soil subsidence also destroyed buildings, deepened local rivers, and created wetlands in places like the Rio Cruces and Chorocomayo, a new aquatic park north of the city. Extensive areas of the city were flooded.The electricity and water systems of Valdivia were totally destroyed. Witnesses reported underground water flowing up through the soil. Despite the heavy rains of May 21, the city was without a water supply. The river turned brown with sediment from landslides and was full of floating debris, including entire houses. The earthquake did not strike all the territory with the same strength. The two most affected areas were Valdivia and Puerto Octay near the northwest corner Llanquihue Lake.East of Puerto Octay in a hotel in Todos los Santos Lake piles of plates were reported to have remained in place. Two days after the earthquake a volcanic vent erupted. Other volcanoes may also have erupted, but none were recorded due to the lack of communication in Chile at the time. The relatively low death toll in Chile, estimated at 6,000, is explained in part by the low population density and by buildings being built taking into account that the region has many earthquakes and volcano eruptions.Other possible reasons include a high number of wooden houses and that coastal towns also tended to be located on higher ground. After the eruption, began the landslides. The earthquake triggered many landslides, mostly near the Andes. These landslides did not cause many fatalities nor significant economical losses because most of the areas were uninhabited with only minor roads. One landslide did cause destruction and alarm following its blockage of the outflow of Rinihue Lake.About 100 km south of Rinihue Lake, landslides in the mountains around Golgol River caused this river to dam up and then burst creating a flood down to Puyehue Lake. The Valdivia earthquake led to the formation of the ONEMI. ONEMI is the Spanish acronym for National Emergency and Information Office. ONEMI helps solve problems after earthquakes, large or small. The Valvidia earthquake was also referenced in two fictional novels, and the tsunami following the earthquake was referenced in a Hawaii Five-O episode titled â€Å"Forty Feet High and it Kills! â€Å".

Anatomy and Physiology Comprehensive Final

The 2000-Meter Row: A Case in Homeostasis Adapted from the National Center for Case Study Teaching in Science* by Nathan Strong At the start 1. Recall that Jim's heart and respiratory rate are increased, he was sweating and that his mouth was dry before the raise began. Explain what is happening to his autonomic nervous system (including which division is the most active) and specify exactly how those ANS responses are creating the symptoms noted.What changes do you think are occurring in the digestive and urinary systems at this time? (8 points) In his autonomic nervous system, the sympathetic division was the most active before and during the race because it is what prepares your body for extra somatic activity. It activated as he was preparing for the race because he was becoming more stressed and nervous. It started in the sympathetic center located in his hypothalamus, and from there led multiple places causing his symptoms.His increased heart rate started when the cardioacceler atory center in the Medulla oblongata sent impulses down the spinal cord to the preganglia and ganglionic neurons of the Cervical and T1-T3 spinal cord segments, then the cardiac and pulmonary plexuses, which then leads to the heart and increases the rate at which it pumps. At the same time, his respiratory rate increased similarly. Impulses sent down his spinal cord through the preganglia and ganglionic neurons of the Cervical and T1-T3 spinal cord segments, to his cardiac and pulmonary plexuses, which then led to a higher breathing rate.The sweating is another response to the activation of his fight or flight mode, the sympathetic division. His body perceived his nervousness as a sign that there is a threat and he may begin to exert more energy and in turn become hot, so it prepares for that by sweating in an effort to cool his body. His postganglionic fibers began to innervate his sweat glands by releasing acetylcholine and activating his muscarinic receptors. The cause of his dr y mouth was his preganglionic fibers which ascend to his superior cervical sympathetic ganglia and inhibited his salivary glands.Finally, during a time where the sympathetic division of the ANS has been activated, the blood flow to the digestive system will be restricted and temporarily restricts digestive activities. Then, in the urinary system, kidney functioning is reduced, the detrusor urinae muscle of the bladder wall relaxes as the internal urethral sphincter contracts, which overall suspends the urinary system. One minute in 2. Consider the power stroke of rowing from the perspective of the actions at the shoulder and elbow joints.Create a table that shows what muscles, under control of what nerves, pull on what bones to cause each action. Be sure to include the action of fixating the shoulder blade and pulling it back. The first column for your table must be the action. This column should describe what is occurring in both English and anatomical terminology (see chapter 9). But only include those actions needed to row the boat. Points will be deducted for unneeded actions. See example below*. (15 points) Action| Muscle| Origin | Insertion | Nerve|Maintain Handle Height:Angular motion of the humerus at the shoulder| Deltoid| Clavicle, spine and acromion of scapula| Deltoid tuberosity of humerus| Axillary Nerve| Pulls Together The Shoulder Blades:Adducts and rotates scapula downward| Rhomboidmajor and minor| Spinous processes of C7 and T1-T5| Medial border of scapula| Dorsal Scapular Nerve| Pulling The Handle Toward Your Body:Flexes the forearm at the hinge joint of the elbow| Biceps brachii| Long head at supraglenoid tubercle of the scapula through the intertubercular groove, short head at coracoid process of scapula| Radial tuberosity| Musculocutaneous Nerve| Pushing The Handle Away From Body:Extend the forearm at the hinge joint of the elbow| Triceps brachii| Lateral head at posterior side of humerus, medial head at distal radial groove of humerus, lo ng head at margin of the glenoid cavity| Olecranon process of the ulna| Radial Nerve| 3. Now, pick one of those muscles and trace their control from the appropriate brain structure all the way to the NMJ. Be sure to include all intermediate structures, synapses, plexuses and nerves. (8 points) Movement of the deltoid begins in the cerebrum of the brain, but more specifically: in the frontal lobe, the premotor cortex is relaying instructions to the primary motor cortex.The primary motor cortex contains the upper motor neurons whose axons will travel down the pyramids of the medulla oblongata and synapse on lower motor neurons in the anterior gray horns of spinal cord segments C5-C6. From there, the ventral rami of spinal nerves C5-C6 form the superior trunk of the brachial plexus, which splits into two divisions. We will follow the posterior division that supplies to extensor muscles. This posterior division then runs into the posterior cord from which the axillary nerve is derived. The axillary nerve’s motor end innervates the deltoid through its neuromuscular junction. 4. Rowing full speed is putting maximum demands on Jim's muscles.What metabolic process is providing most of the energy for Jim’s muscles at this point and why do Jim's muscles feel like they are burning? (5 points) As Jim’s muscles are at maximum demand, his mitochondria are unable to produce the needed ATP through aerobic respiration because oxygen is unable to diffuse fast enough into his muscle fibers. At this time anaerobic glycolysis takes the lead as the metabolic process producing two-thirds of the ATP needed so that his muscles can continue contracting. However, during glycolysis, there is soon more pyruvic acid produced then can be used at the time. That pyruvic acid gets converted to lactic acid, which is an organ acid that is able to dissociate in body fluids.The lactic acid breaks up into hydrogen ions and negatively charged lactate ions that lowers intracellul ar pH and causes a burning sensation in his muscles. 5. Trace the sensation of pain in Jim’s left Quadriceps muscle from the receptor to perception in the brain. Be sure to include the nerve and all intermediate structures involved in relaying this sensation. (8 points) When Jim felt a pain sensation in his Quadriceps muscle, it began with the local nociceptors being activated. A signal was then transmitted from his nociceptor neurons, through the dorsal root ganglia where the cell bodies are located. Then, the signal is processed through the Central Nervous System, reaching the interneurons and being relayed to the brain through the lateral spinothalamic tract.The lateral spinothalamic tract and interneurons end in the ventral nuclei of the thalamus, where third-order neurons process and relay the painful sensation to the primary sensory cortex. 6. Since the end of the first minute, Jim has decreased the demands his muscles are making. What metabolic process is now providing most of the energy for his muscles? What muscle protein has been storing Oxygen for this activity? (6 points) Now that Jim has decreased the demand on his muscles, they are able to function primarily on aerobic metabolism, breaking down pyruvic acid to produce ATP. However, he is still working at a high level of energy, which will require a lot of oxygen. Myoglobin, an oxygen-binding protein helps to supply some of the needed oxygen for aerobic respiration. 7. What energy molecules is Jim’s body consuming?What might Jim have done the night before to increase his endurance today? (4 points) During the race, Jim was using broken down glucose from the glycogen reserves in his sarcoplasm. A good way to improve endurance during a race is to eat a meal full of complex carbohydrates. These carbs provide energy the next day because they take longer than almost any other food to be broken down, and as they are slowly digested they continue to provide energy throughout the race. 8. Id entify the components of the homeostatic control system that is keeping Jim’s body cool and then explain specifically how that system works, including the messaging system involved. (8 pts)The homeostatic control system that maintains body temperature is called thermoregulation. The system has a control center known as the thermoregulatory centre that’s located in the hypothalamus. There are two sets of temperature receptors that send information to the control center. One monitors the core by looking at the temperature of the blood that flows through the brain, and the second monitors the external temperature through the receptors in the skin. Once his body temp rose above 37. 20C, the higher temp stimulated his heat loss center. There are then two effectors that were at work lowering his body temperature. First, the smooth muscle of his arterioles supplying the skin relaxed, which caused vasodilation.Second, his sweat glands became more active and began cooling his s kin surface. Finally, as his body regains its normal body temperature and that information gets to the hypothalamus, the control center becomes dormant. 9. Recall that Jim could see boats on either side of him. Trace the image of those boats to perception. (Include all focusing, transduction, transmission and perception processes and structures) (10 points) As Jim was rowing and watching the boats beside him, the first step was reception. This happens as light is entering his eyes and the lens is focusing it onto the fovea of his retina, which is where his photoreceptors are located.The second step is transduction, during which the rods and codes are converting the electro-magnetic energy into electro-chemical nerve impulses. This is the step that allows the light energy to move across our optic nerve and be processed in the brain. That step where his nerve impulses are sent to his primary visual cortex is called transmission. The next step, selection, is where feature detector cell s are working to break up the image. Then during organization, through multiple visual perceptual principles, the information is being reassembled into a way that we can understand it. The image goes to both our temporal and parietal lobes so that we can identify and determine where the object is located.Finally, the interpretation stage is where the boats he saw where both identified and given meaning. 10. Jim has stopped rowing and his muscles are now at rest. Why are his heart and breathing rates still so high? (3 points) His rowing competition took a lot of energy and oxygen. Once it was over, his body needed to restore what was used during his exercise. A higher breathing rate brings more oxygen into the lungs, and a higher heart rate pumps blood so that the oxygen can get into the blood stream then into the muscles. Oxygen in the muscles will allow restoration of the ATP levels. 11. Why did Jim lose 4 pounds during this event? What tissue/body material was lost and will this b e a â€Å"permanent† weight loss? (5 points)About half a pound out of Jim’s four-pound loss could have been the glycogen reserves in his muscles that were depleted, but most of the weight loss was due to water loss while he was sweating during the race. Both of these things will be restored in his body though, causing the weight loss to only be temporary. Works Cited â€Å"Breathing Rate And Heart Rates After Exercise. † LiveStrong. Demand Media, Inc. , 14 Jul. 2011. Web. 1 Dec. 2012. â€Å"Chapter 6 – Visual Perception. † Oup. n. p. , n. d. Web. 1 Dec. 2012. PDF file. â€Å"Homeostasis. † BiologyMad. IHW, Mar. 2006. Web. 1 Dec. 2012. â€Å"Keeping Your Autonomic Nervous System Healthy. † DrWilson. The Center For Development. June 2011. Web. 27 Nov. 2012. â€Å"Muscles Used In A Rowing Machine. † LiveStrong.Demand Media, Inc. , 3 May, 2011. Web. 28 Nov. 2012. â€Å"The Body Can Use Glycogen As An Energy Source When Aerobic Exe rcise Lasts How Long? † LiveStrong. Demand Media, Inc. , 7 Jul. 2011. Web. 30 Nov. 2012. â€Å"The Brachial Plexus. † UpState. Health Science Center, n. d. Web. 28 Nov. 2012. â€Å"What Is Most Of The Weight Loss From When Individuals Lose Weight Quickly? † LiveStrong. Demand Media, Inc. , 28 Apr. 2011. Web. 1 Dec. 2012. â€Å"Why Do You Sweat When You’re Nervous? † WiseGeek. Conjecture Corporation, 15 Nov. 2012. Web. 27 Nov. 2012. â€Å"Why You Should Load Up On Good Carbs The Night Before A Big Game. † FitDay. Internet Brands, Inc. , n. d. Web. 30 Nov. 2012.

Philosophy: Dialogue with Socrates Essay

â€Å"Socrates, good day!† exclaimed Person. Socrates is still mesmerized in this realm unbeknownst to him. Dazed and confused, he sees a figure, a person looking right at him. He replied, â€Å"Good day to you to. May I ask you questions about this world? I suppose you are a citizen of this state.† â€Å"I would gladly entertain your queries, but I have questions too, questions that only you can answer,† retorted Person. â€Å"I will bring the truth upon your inquiries, if you allow me the pleasure of asking you one question. I need help in bringing out the truth so that the decision I make would be based on reason.† â€Å"The pleasure is mine,† said Socrates, â€Å"I will help you bring the light of truth into your question, what is it that you ask?† Person then hesitated, but replied eventually, â€Å"Should I submit my school requirement? The teacher asked to write something philosophical, something uhm†¦ something about a dialogue.† â€Å"Then it is an obligation, I suppose, and every obligation must be fulfilled. This is a moral act, pious according to the laws of my state, Athens. One must never disrespect the state, it is immoral.† â€Å"I do not want to submit my paper, it gets in the way of my hobbies and friends, yet at the same time, I do not want to fail my obligations to my school, â€Å" Person said. â€Å"This obligation, to whom is it addressed,† Socrates asked. â€Å"The obligation is for my teacher,† replied Person. â€Å"Why would you not obey your obligation? Did you enter this obligation as an agreement,† inquired Socrates. â€Å"Why, I, ah I entered the obligation as an agreement when I enrolled. I entered it willingly but the teacher gets in the way of my hobbies and friends,† said Person. Socrates asked: â€Å"If the teacher is a hurdle to you, would you then disregard this authority? What is the basis of your rebellion against authority?† And Person replied: â€Å"I would disregard the authorities, but there are consequences, like a failing grade. If I fail, I would either repeat this course, or I would have a hard time applying for a job after I graduate if most of my grades show my disregard for requirements and obligations.† â€Å"Then, following this authority is a virtue?† â€Å"Yes!† exclaimed Person. â€Å"And entering an agreement or obligation willingly is acceptable?† â€Å"Yes,† said Person proudly. â€Å"If the authority gets in the way of your time with friends, does this mean that the authority is immoral?† â€Å"No.† whispered Person. At this point, Socrates is fuming mad. I know that he is a just man. Plato said so, when I conversed with him moments ago. And now I know that Socrates is not only just but also virtuous. He is attached to truth itself. Furiously, he said: â€Å"Then, I would say that you are not virtuous because you dare defy authority that is virtuous! You are also immoral, for defying your obligations that you entered willingly! Why then did you enter this agreement if you are not agreeing with it?† â€Å"Because studying is required to be smart and successful, I want to be successful†¦ and being smart means that you gain wisdom,† Person shyly said. The face of Socrates brightened a bit: â€Å"You are wise in saying that Person,† exclaimed Socrates, â€Å"because the beginning of wisdom is the recognition of your ignorance. However, knowing that you are ignorant but not following the virtuous path towards truth and wisdom only means that you are foolish. Do as you please, do not fulfill the obligations of your agreement, and you will lose your identity as a Person. What difference do you have then from beasts?† â€Å"I am not a beast. And I am not foolish. I will then, submit to my obligations, I will write my paper. So, Socrates, let us move on, what are your questions about this realm?† Person said eventually.

Maternal vitamin D and brain development Research Paper

Maternal vitamin D and brain development - Research Paper Example However, scientists are conducting further studies to find the maximum possible quantity of Vitamin D intake for pregnant and lactating mothers, while considering any possible side effects of its higher dose intake. Nevertheless, it is an established fact that this supplement helps in the development of skeletal and brain of the fetus, during pregnancy without any malfunction. While deficiency of Vitamin D is common in female population of countries with less sunshine, it is more evident in women with darker skin pigmentation.. In addition, research has found that 9.2 percent females are having such deficiency against the 6.6 percent males. The benefits of Vitamin D intake during pregnancy include helping in development of strong bone structure, as its deficiency results in reduced bone mineral content for the newborn. Chances of miscarriage are reduced with intake of Vitamin D that produces immunological changes in the mother, during early stages of pregnancy. In addition, medical research has found a link between Vitamin D and medical abnormalities like schizophrenia, as its deficiency can effect the normal brain development causing such kind of malfunction during adulthood.(Hollis & Wagner, 2014) Research has also collected evidence that Vitamin D intake during pregnancy can help in preventing the development of immunological diseases like asthma, wheezing, allergic infections, diabetes and respiratory tract infections, after the child grows into adulthood. Skull bones are also strengthened by the intake of this supplement as its deficiency means week skull bone structure that can cause brain injury at the time of delivery. Several epidemiological studies suggest that while Vitamin D deficiency is common in almost all pregnancies, it is more prevalent in black women, as they represent 29 percent of the total females having low intake of Vitamin D, against 5 percent of

We are Seven(Lyrical Ballads) Term Paper Example | Topics and Well Written Essays - 2000 words

We are Seven(Lyrical Ballads) - Term Paper Example Wordsworth wrote the poem ‘we are seven’ at the age of 18 when he was going on a journey with his best companion Coleridge. ‘Wordsworth’s most deeply held conviction is his belief that the scope for poetry was often best provided by memory.’ As we also observe in this particular poem that the little girl that he talks about is actually someone he had met on his journey in a similar setting. As stated, ‘We Are Seven was inspired by a little girl he met in the area of Goodrich Castle.’ The poem comprises of sixteen four lined stanzas with the exception of the last stanza that consists of five lines. The rhyme scheme of the poem is ABAB. The poem is in the form of a conversation between a stranger and a little girl. The technique of writing the poem in a dialogue form enhances the beauty of the poem as it helps in retaining the interest of the reader, as he is curious about the end result of the conversation. The title of the poem hints about a sense of security that is related to the knowledge of having strong family bonding as observed from the word ‘We’. It has a tone of finality to it. The two letter word hold a lot of meaning as it also indicates the element of stubbornness and conviction of belief that nothing can change the reality i.e. we are seven. Number ‘seven’ can in itself be a reference to ‘Shakespeare’s seven stages’ of a man’s life as the readers later observes that this poem also draws a contrast between the perspective of life from the eyes of a child and an adult and shows the manner in which a person loses his idealism in order to grow up. The poem is basically about a conversation between a man and a little girl about her family and loved ones. The stranger inquires about her brothers and sisters and the girl replies that we are seven. This reply leads to the formation of the whole conversation that takes place in the poem.

Assignment 1 Example | Topics and Well Written Essays - 500 words - 14

1 - Assignment Example New Jersey average sales tax plays a minimal significance as compared to the other states as 0.0% indicates lack of local government participation in collecting sales taxes. However, the value of 0.0% in average sales tax at the local level is also important in that it shows business are exempted from sales tax. Additionally, when considering the state level average sales tax, it is shown that New Jersey is ranked 1st with 14.1% rate. This makes New Jersey very important in contributing to the national sales taxes. Question 2: Look at the local property tax proportion. How important is the property tax to the cities and counties in your state†¦ more or less important as compared to the average of all states? More or less important as compared to the 6 states we’ve looked at? New Jersey has proportional property tax of 55.1% as compared to the other states that do not exceed the 30% mark on the sale while it is more than twice the national average of 26%. To the cities and counties within New Jersey, a 55.1% property sale proportion provides the maintenance of the cities and the county amenities and infrastructure. However, the high property tax at the local level indicates high rental rates or high acquisition of real estate establishment. In addition, the state level averages display an abnormal comparison when compared to the national average. The national average is 26.8% against the local level of 55.1%. In conclusion, the vast acquisition of property in New Jersey contributes the high rate of property tax at the local level. Question 3: Look at the spending on education at both the state and local levels for your state. Including both state and local levels of spending, consider the differences between your state and the national averages, and answer the following question: is your state, taking into account both state and local levels of spending, nearer the top or nearer

Ask the Author Essay Example | Topics and Well Written Essays - 250 words

Ask the Author - Essay Example They are short and direct sentences. They help to bring out the idea that you are not embarrassed to have a dollhouse in your living room. It sets the stage for the rest of the essay as you embark on recreating your childhood memories and synchronizing them with your current life as you rebuild the dollhouse. The choice of gender and the names for your dolls also aid in understanding the nostalgic tone you employ in the essay. You also employ figurative language and imagery to convey your theme of nostalgia to the audience. For example in the fifth paragraph, you use a simile when emphasizing the need for using scale to make everything in a dollhouse. The audience gets to understand that lack of paying attention to scale in a dollhouse will make it look crazy like an Alice in wonderland hallucination (Haegele). Your description of remodeling the dollhouse is also vivid and the reader can create mental pictures throughout the essay and see you rework the dollhouse. The use of figurati ve language and imagery helps bring out the nostalgic

Proofs for the Existence of God Essay Example | Topics and Well Written Essays - 1000 words

Proofs for the Existence of God - Essay Example There are unanswered questions even today about the importance and existence of God as creator of this universe or the galaxies that astronomers see through their ever more powerful telescope. If it is conceivable that this universe had a beginning and will have an end, then it is logical to assume that it must have had a creator, since nothing can be created out of nothing. While John Leslie in his treatise on the subject of ethically required existences argues that there must be proof of God somewhere in the system of things, St Anslem of old puts the cart before the horse and argues that the importance that religion and mankind gives to God proves his existence (Anslem, 4)1. Explication To my mind, both philosophers are arguing for the existence of God, but each from a different standpoint. John Leslie, in his argument for what he calls ‘ethically required existences’, relies on the tenets of naturalism and prescriptivism to explain his viewpoint (Leslie, 1972:222)2. St. Anslem however takes a more unconventional approach and states that to think of God is to think of the Greatest Power that the Universe has ever known, and undoubtedly since some Power created this Universe and every living and inanimate thing out of nothing at all, that Power can only be God and belong to God. No one can create something out of nothing except God. Therefore it is imperative that we believe in the existence of God, the Creator and Master of All the known universe and its galaxies etc. It is far better to accept the existence of God because each creature in the universe is the product of intelligent design and that presupposes a creator. Main Argument John Leslie starts with the notion that we cannot label anything as intrinsically good or bad unless we know what good and bad is, therefore we are making a judgment that can only depend on prior knowledge or something that is inherent in man’s nature or existence. If morality or ethical behavior is what sepa rates us from the animals or at any rate, the creatures that lie below us on the totem pole of existence, then there is someone or something that put it in our hearts, or minds and our souls, and that could only be God. No wonder it is often said that ‘Conscience is the voice of God in man’. The very fact that we all come into this earthly existence with an inbuilt sense of morality is proof enough of the existence of God, a creator that prefers us to be good and do good, but has given us free will all the same, in order to test our level of obedience to him in this earthly life. To support St. Anslem’s argument, since it is so confusing, I prefer to put forward what has been called Pascal’s Wager to prove the existence of God. Pascal’s Wager induces us to wager that there is a God, rather than there is not. He has very interestingly drawn out parallels whether we believe in God or do not believe in God because we cannot do both. Either we believe i n the existence of a Supreme Being or we do not. But suppose if we did and there is indeed a God that meets us at the Pearly Gates or whatever as we pass into the afterlife. In that case we would indeed be pleased that we assumed correctly that God did exist. Indeed this assumption also makes our moral life on Earth easier as well. We take pains to do good and be good because

Unit 3DB The Green Revolution Research Paper Example | Topics and Well Written Essays - 250 words

Unit 3DB The Green Revolution - Research Paper Example In this regard, energy conservation should be highly rated and considered if indeed the long term effects of environmental conservation are to be realised. In order to reduce personal energy consumption, the following changes can be made that would in the long run create a significant difference. To save car fuel energy consumed on daily drives to work, commuter trains and or bicycles can be used to achieve the same. This will not only reduce gasoline fuel consumption, but also help in environmental pollution. Concerning the other forms of energy use, such as the ones on lighting heating and cooking, renewable energy, specifically, solar and wind energy can be utilised. These energy forms are sustainable and also clean. On the other hand, to increase energy efficiency requires discipline in the use of already in place energy sources. This means small changes such as switching off unnecessary lights around the house, and using energy efficient light saver bulbs. In addition to this, electric appliances should be used as per the manufactures specifications. Household electric appliances account for nearly thirty per cent of home electric consumption. Therefore, efficient use will directly translate to efficient energy consumption. An electric vehicle consists of electric motors that are used to drive the car. These can be powered externally, through stored electric energy such as batteries, and through an internal energy source such as generators. Electric cars are considered to be efficient, clean, and most of all environment friendly. In this regard, yes I would purchase an electric vehicle because of its long term benefits. Fuel costs are bound to rise, that is guaranteed, In addition to that fossil fuel is not renewable and as such contributes to environmental degradation. Based on this alone, using an electric vehicle contributes to energy conservation, has long term cost benefits, and is also energy

Integrated Communication Plan Research Proposal

Integrated Communication Plan - Research Proposal Example UK gaming market is the third most important market in the world, and it is the largest European market [1,2]. According to [3] there are more than 33.6 million gaming users in UK market in the year 2012. Moreover, this market generated revenue of  £2.04 billion in the year 2014, and this is around 7% more than 2013 (Dring, 2014). According to Yahoo! News, with the growth of the industry there are more and more jobs coming up in the UK market (Brinded, 2014) The total value estimated of the video gaming industry is GBP 1 billion. Around 33 million people in UK play video games (IAB UK, 2011). Thus, the market segment is very large. These gamers can be categorized into different types. Among these types, 19% are the regular gamers and casual gamers, or social gamers are around 26%. Therefore, this segment of social or casual gamers can be important segment that Nintendo WiiU can target. The age group of casual social gamers is in the age group of 35 to 44 years, and most of these pe ople are parents. At the moment, Nintendo WiiU is focusing on regular gamers that are around 19%. Many people use gaming as time consuming activity.Gamers can get negative attention, and this can have negative influence and gain negative attention in the media. Thus, it is important for Nintendo to not come up with such games that can have negative attention in the media.(Brinded, 2014) Economic factorsThere has been an increase in the demands of the games. The demand of different games has been increasing.

Create a business plan Assignment Example | Topics and Well Written Essays - 1500 words

Create a business plan - Assignment Example However, the company does not aim to restrict itself to this segment and shall provide its services to a broader market. The products offered shall include home delivery, office delivery, Food for a week and other new and upcoming products. The company shall be in a profitable position from 2013 and look to consolidate its position by increasing awareness and market share. Distribution networks will be setup that will help the company in gaining a competitive advantage. Company Profile Dream Inn is more than a restaurant serving top quality food to its customers. Dream Inn is a concept, an idea that originated earlier in the minds of its creators after observing the quality of food and service being provided by other vendors. The creators had the vision and foresight to identify various unfulfilled needs of customers in the Bahraini market. While these restaurants were providing top notch food to their customers, there are some areas of the food order and delivery value chain that le ft something to be desired. For instance, the creators recognize that customers are individuals and vary in all aspects such as ordering time and buying patterns. Dream Inn is open 24/7 to cater to customers at all hours, day and night. Secondly, the creators identified another need that remained untapped which was the requirement for customers to have home and office delivery at all times and fulfilled this need by decentralizing operations and creating multiple offices which allowed the company to cater to customers in a timely manner. Another need serviced by Dream Inn is through the use of technology – by the creation of a user friendly website which allows customers to view the products on offer and place orders easily and have their food delivered within the agreed time limits. This is particularly helpful for professionals who spend most of their time in front of the computer. Marketing Strategy Market Share The company will aim to gain a market share of 10 percent of food delivery services by 2015 and look to increase market share to 25 percent by 2020. Product Profile Dream Inn provides a vast array of services to its customers for their convenience. These services include: Provision of user friendly website for viewing the different products on offer and placing an order online for the convenience of the customer Provision of 24/7 door to door delivery services throughout the country Established outlets for convenience of customers to place orders on their way from home or office Creation of new value added services such as Food for a Week, which will allow customers to book a weekly menu in advance. This will be particularly helpful for those customers who are professionals and lack the time to order on a daily basis and can decide their weekly menu in one single attempt. This product will be equally beneficial for single bachelors who are immigrants and have moved here in order to make a living and do not have the time or knowledge to prepar e their own meals and cannot afford to order on a daily basis from high priced restaurants. Menu includes items from various fast food restaurants, Italian, Asian and cuisine of various countries. Since the products are being purchased from other restaurants, and Dream Inn is aiding their sales revenues, Dream Inn shall be able to purchase these products at a substantial discount from suppliers and gain a

Implementing ERP Solution Projects in SMBs Essay Example for Free

Implementing ERP Solution Projects in SMBs Essay Managing and developing intellectual capital in many of today’s organizations is becoming the greatest asset. Different firms of different sizes operating in different sectors are seeking a way of performing this task effectively and efficiently. Among the different tools under considerations, many consider Enterprise Resource Planning (ERP) software packages essential tools to effectively manage, retain and share knowledge among stakeholders at all echelons. ERP implementation causes changes to the receiving organization given its comprehensiveness and integrity. As a result challenges which results into additional risks and realization of new opportunities arise and proper action must be taken to avert or reinforce the challenge for better results. ERP solution system is as an opportunity for business entities whether small or large to use software applications that are specifically designed to upgrade the various business functions and attain the best business practices (Markus and Tanis, 2000, Marnewick and Labuschagne, 2005). Effective implementation of ERP software applications ensures that the major functional parts of a business enterprise are linked together in a common amalgamated software system (Sandoe et al, 2001, Rao 2000). This process makes it possible for the business activities to be instigated more efficiently and cooperation among the workers becomes more effective through the interactive information system. The process of implementing ERP in Small and Medium Businesses (SMBs) is beset with extra challenges and opportunities due to their specialty. The SMBs have limited financial and human resources, limited experience in project management and sometimes limited managerial competencies which determines the agility of their operations. Problem Statement Implementing ERP, projects require specialized application because they affect the receiving organization to different degrees. In implementing an ERP, solution divisions and departments within an organization have to be integrated into a single business platform, which affects the business model and the organization culture (Markus and Tanis, 2000). This makes the project risky and intricate. Due to global business factors, economic expansion and IT revolution ERP solutions are becoming a requirement for business success. SMBs being key players in the economic activity are not left out in this competition. However, the process and success stories of ERP solutions in SMBs is lacking as past studies mainly focused on the large scale enterprises ERP solution process and application. In addition, the present trend of ERP solution project implementation by SMBs in the diverse business sectors and industries calls for the exploration of the opportunities and challenges of Implementing ERP Solution Projects in SMBs to pave way for the identification of ways of avoiding or minimizing losses in the implementation process (Soh et al, 2000). SMBs organization structures and organizational cultures are not all well defined. This coupled with the rigidity of the organization structure and culture present serious challenges to the implementation of ERP projects in SMBs. Additionally ERP projects are more successful in easy to change and agile organizations. However, unlike in large companies, the senior management team of the SMBs is normally part of the daily business operations and lacks in-depth knowledge and skills necessary to have organized long-term plans for the business and even the adoption of ERP solution projects. Similarly low capital base and lack of properly trained personnel have remained a major setback in the running of the functions of SMBs. This problem is compounded by lack of sufficient funds to sustain training and engage quality consultants in such trainings. According to Sandoe et al (2001) many SMBs lack dedicated IT staff able to perform the risk management function exposing major business operations to unnecessary risks. Likewise, within internal functions of a SMB, organizational changes that would give room for adoption of technology are limited due to lack of unused resources. The impact of unsuccessful implementation of ERP solution to a SMB are said to be greater to the entire operations of the business enterprise while the success of wisely implemented ERP system will have a whole organizational positive impact (Rao 2000).

Learning Difficulties Encountered By Efl Students English Language Essay

Learning Difficulties Encountered By Efl Students English Language Essay Recently, listening has gained more and more attention in foreign language learning. In learning a foreign language, it is suggested that the most important step should begin with an effort to listen. (Rubin Thompson, 1994) Listening provides input for learners to make learning occur and listening exercises draw learners attention to new forms in language, such as new vocabulary items. (Rost, 1994) Listening can be regarded as a necessary skill in the diagnosing and preparation of foreign language students and can even be served as a good predictor of language achievement. In consequence, listening comprehension acts as a pivotal role in foreign language learning. (Oxford, 1993) In this essay, three issues are discussed. Issue 1 states listening difficulties in second language acquisition. Underwood (1994), Chiang and Dunkel (1992) and Rubin and Thompson (1994)s viewpoint are discussed. Issue 2 proposes taxonomies of the factors affecting listening difficulties. Boyle (1984), Yagang (1993) and Rubin (1994) s point of view of the factors affecting listening comprehension are referred to. Issue 3 mentions studies in listening difficulties of L2 listeners in foreign countries. Tauroza and Allisons (Rubin, 1994) study is about speech rate. Boyle (1984)s study is factors most frequently mentioned in listening comprehension. Lynch (1997)s study is a case study of a intermediate-level learners progress in listening comprehension. Goh (2000)s study discusses listening comprehension problems. BODY Chapter 1 Listening difficulties in second language acquisition Underwoods (1994) point of view ¼Ã… ¸ Underwood (1994) identified seven potential difficulties in listening comprehension as: (1) lack of control over the speed at which speakers speak, (2) not being able to get things repeated, (3) the listeners limited vocabulary, (4) failure to recognize the signals, (5) problems of interpretation, (6) inability to concentrate, (7) established learning habits. Many language learners believe that the greatest difficulty with listening comprehension is that the listener cannot control how quickly a speaker speaks. (p7) They feel that the utterances disappear before they can sort them out. http://nccuir.lib.nccu.edu.tw/bitstream/140.119/33414/7/95100307.pdf They are so busy working out the meaning of one part of what they hear that they miss the next part. Another difficulty is that listener is not always in a position to get the speaker to repeat an utterance. This is particularly likely to be the case when students are on the edge of conversation outside the classroom. For people listening to a foreign language, an unknown word can be like a suddenly dropped barrier causing them to stop and think about the meaning of the word and thus making them miss the next part of the speech (p 17). And students need to learn to listen for the signals in order to be able to connect the various utterances in the way the speaker intended them to be connected. (p18) Students who are unfamiliar with the context may have considerable difficulty in interpreting the words they hear even if they can understand their surface meaning. (p19). Inability to concentrate can be caused by a number of things, but in listening work it is a major problem, because ev en the shortest break in attention can seriously impair comprehension. (p19) Outside factors may well make concentration difficult, too. An inferior machine or poor recording can make it very hard for the students. As for establishing leaning habits, when the learner can more readily accept the frustrations involved, he will be more prepared to strive for a partial and incomplete understanding of what is being said. (pp16-19) Rubin and Thompsons (1994) point of view Rubin and Thompson list three common problems in learning to listen to a foreign language. The first problem is that the speaker talks too fast. If the listener can not follow the speaker, the listener can let the speaker know that he is not following. He can ask for repetition and slowing down the speed, seeks clarification, rephrase, and repeat. The listener can pay attention to intonation and tone of voice, focus on question words such as who, what and when and assume that the here and now are relevant. That is, the sentence is directly related to the subject they have just been discussing. Assume that what a person says is directly related to something he or she is experiencing at that very minute. The second problem is that the listener is not getting anything out of foreign language TV and movies. If the listener could not understand the foreign language TV and movies, they should try to take control of his listening by predicting what he was likely to hear. For example, use vi sual clues and use his background knowledge. Anticipate information in a segment by relying on your knowledge of what such a segment is likely to contain. Listeners could also use information from the segment itself and determine the genre of the segment. Knowing the genre of a segment will help you determine how best to approach it. For instance, if it is an interview, then concentrate on the questions. If it is a news report, a who, when, where strategy will work best. If it is a drama, look for the story line. Listeners could listen to familiar elements, listen to familiar-sounding words, listen to and jot down repeated words, learn to recognize numbers and learn to recognize proper names. The third problem is that the listener tends to stop listening when he hears an unfamiliar word or phrase. Many learners, particularly in the early stages of language learning, panic and lose their concentration when they hear an unfamiliar segment. As a result, they miss portions of the passag e that might have helped clarify the unfamiliar word or segment. The listener should concentrate on familiar elements and keep listening. Understanding something is better than getting nothing at all. If you continue listening, chances are that you will comprehend at least some parts of the massage. It is possible that the portions you missed were not very important after all. Chiang and Dunkels (1992) point of view Chiang and Dunkel (1992) pointed out that listeners comprehension in English may be thwarted by a number of cognitive and linguistic factors as well as academic and cultural issues, including: (a) inability or lack of opportunity to engage in communicative interaction with the second/foreign language teacher or lecture; (b) inability to detect the main points of the lecture or to grasp the usual goals of particular genres of discourse situation of which the discourse is a part; (c) unfamiliarity with the structure and type of the discourse ; (d) inability to apprehend discourse markers and logical relationships in the English lecture; (e) inability to comprehend lecture speech delivered at faster rates of speed; (f) limited short-term memory for English input; (g) failure to use appropriate cognitive or learning strategies; (h) poor inference abilities in English; (i) limited proficiency in English; (j) lack of prior knowledge about the content of the spoken or written text; and (k) inability to process L2 input devoid of speech modification such as elaborations or redundancies. Of these difficulties confronting L2 learners, Chiang and Dunkel explored the effect of three of them. The first situation was when the listeners had limited listening proficiency in English, the second situation was when they lacked prior knowledge about the topic of the L2 lecture, and the third situation was when they were not supplied with modified speech. The results revealed a significant interaction between prior knowledge and text type. Chapter 2 Taxonomy of the factors affecting L2 listening difficulties Boyles (1984) three categories of factors Boyle (1984) began with a survey of the factors most frequently mentioned in the literature on listening comprehension, including three categories of factors. The first category referred to the listener factors, including experience in listening to the target language, general background knowledge of the world, educational background and type of school, knowledge of the target language in its various aspects, memory, powers of analysis and selection and motivation and attitude of the listener to the speaker and to the message. The second categories, the speaker factors, contain language ability of the speaker: native speaker-beginning level non-native speaker. Speakers production: pronunciation, accent, variation, voice affect, too. Speed of delivery and prestige and personality of the speaker count. The third category, factors in the material and medium, comprise difficulty of content and concept, especially if the material is abstract, abstruse, highly specialized or technical, len gthy or poorly organized. Acoustic environment such as noise and interference and amount of support provided by gestures, visuals also have influence on listening comprehension. Yagangs (1993) four aspects of factors http://eca.state.gov/forum/vols/vol31/no1/p16.htm Instead of three categories, Yagang (1993) proposed that the sources of listening difficulties came mainly from the four aspects: the message, the speaker, the listener, and the physical setting. The message factors comprised content and linguistic features. In content which is not well organized, listeners cannot predict what speakers are going to say. And if listening materials are made up of everyday conversation, they may contain a lot of colloquial expressions, such as guy for man. Students who have been exposed mainly to formal or bookish English may not be familiar with these expressions. The speaker factors consists of redundant utterances, such as repetitions, false starts, re-phrasings, self-corrections, elaborations, tautologies, apparently meaningless addition such as I mean or you know and speakers personal factors such as their accents. Learners tend to be used to their teaching accent or to the standard variety of British or American English. They find it hard to und erstand speakers with other accents. The listener factors played a more important role in EFL students listening. For example, foreign language students might be not familiar enough with clichà © and collocations in English to predict a missing word or phrase. For example, they can not be expected to know that rosy often collocates with cheeks. EFL students might be lack of sociocultural, factual, and contextual knowledge of the target language.   (Anderson and Lynch 1988).It can present an obstacle to comprehension because language is used to express its culture. Factors in physical setting included noise, both background noises on the recording and environmental noises, could carry the listeners mind of the content of the listening passage. Listening material on tape or radio lacks visual and aural environmental clues. Not seeing the speakers body language and facial expressions makes it more difficult for the listener to understand the speakers meaning. Unclear sounds resultin g from poor quality equipment can interfere with the listeners comprehension. Rubins (1994) five categories of factors Rubin (1994) classified these listening factors into five categories: text, interlocutor, task, listener and process characteristics. Text characteristics referred to acoustic-temporal variables, acoustic-other variables and morphological and syntactic modifications (including restatements). Acoustic-temporal variables are speech rate, pause phenomena, and hesitation. Acoustic-other variables are level of perception, stress and rhythmic patterning perception and L1 and L2 differences. Variables of morphological and syntactic modifications are redundancy, morphological complexity, word order and discourse markers. Text characteristics referred to text type. Visual support for texts is also an important variable. Interlocutor characteristics referred to variations in the speakers personal characteristics, such as gender, pronunciation, accent, expertness and so on. Listener characteristics are listeners language proficiency level, memory, attention, affect, age, gender, learning disabi lities in L1, and background knowledge as well as aptitude, processing skills, background biases, motivation, and confidence level. Process characteristics referred to how listeners interpret input in terms of what they know or identify what they dont know. Top-down, bottom-up and parallel processing is being examined in L2 contexts. Current views of listening comprehension propose that listeners actively process language input. Two types of processing have been discerned: cognitive strategies and metacognitive strategies. Research on listening strategies includes: work on several languages; work contrasting strategy use at several proficiency levels; work with interactive or transactional listening; work with cognitive and metacognitive strategies; work considering the relation of strategy use to text, task, and setting. Chapter 3 Studies in listening difficulties of L2 listeners in foreign countries Tauroza and Allisons ( )studyspeech rate Griffiths suggests that different language have different normal rates and the rates defined in studies using English can not be applied exactly to studies of other languages. Most research quotes a normal speech rate of 165 to 180 words per minutes for native speakers of English. On the other hand, while Foulke reports a threshold (the rate at which comprehension begins to decrease rapidly) level between 250-275 w.p.m., others states that comprehension decreases as a function of mental aptitude and difficulty level. Tauroza and Allison compare normal speed of British speakers for four types of speech. They found that while the mean for radio and interview speech events lies within the range of 160 to 190 w.p.m., the means for conversation and lecture categories are outside this range. The mean rate for conversation in words per minute was 210, while for lectures, 140. They note further that thirty-three percent of their lecture data was slower than 130 w.p.m. and twenty-three percen t of the conversation data was faster than 220 w.p.m. The issue of normal speech rate is one that still needs a great deal more research that takes into account all of the variables mentioned above. (Rubin, 1994) Boyles (1984) study-factors most frequently mentioned in listening In Boyles (1984) study, 30 teachers and 60 students in Hong Kong were asked to list the six factors which they considered the most important in aiding or hampering the effectiveness of listening comprehension. It was interesting to know that the students gave much more importance to vocabulary than teachers did. It was surprising that the students mentioned two factors, memory and concentration, barely mentioned by the teachers. In addition, the students considered that there was a possible relationship between their reading habits and their listening comprehension, which was not mentioned by the teachers. On the other hand, the teacher seemed to specify the linguistic factors more sophisticatedly. The teacher would specify the factors as ability to pick up clues, complex syntactical structures, stress and intonation and interference from Chinese. On the contrary, the students just indicated that the lack of general language ability or the difficulties in English listening comprehens ion. Lynchs (1997) study-a case study of an intermediate-level learners progress Lynch (1997) conducted an ethnographic study of a Japanese student who attended English language courses at the Institute for Applied Language Studies, the only one taking an undergraduate course in economics at the University of Edinburgh. His scores on the listening tests were relatively low in comparison with his reading and grammar scores with the other students in class. A number of possible reasons were found to explain his difficulties in listening comprehension. First, he was the youngest member in his class so that he was unwilling to engage in negotiation with his seniors. Second, he was the only undergraduate student with an economic background in his English class so that he viewed himself as insufficient in some general background knowledge. Third, he joined Course 3 in the EAP program, skipping the basic class, Course 1 and 2. Therefore, he thought he needed more time to get used to negotiate with others in English. Fourth, his lowest listening score disappointed him gr eatly. The perceptions of the subject had made a substantial influence on his English learning. Gohs (2000) study-listening comprehension problems Goh (2000) investigated the comprehension problems of second language listeners in a cognitive perspective. She identified real-time listening difficulties faced by 40 Chinese undergraduates and examined their difficulties within the three-phase model of language comprehension proposed by Anderson. (1995). The data were collected from learners self-reports in their diaries, semi-structure interviews and immediate retrospective verbalizations. The data revealed 10 problems that occurred during the cognitive process phases of perception, parsing, and utilization. She also, made a comprehension between two groups, high ability listeners and low ability listeners. Each group consisted of eight students selected according to their grades in a post-instruction standardized proficiency test, the SLEP test of Educational Testing Service 1991. She found that listeners with highly ability and low ability both had a perception problem with recognizing words they knew. Another problem they both shared was parsing problem that they quickly forgot what they thought they had understood. In addition to these two problems, high ability listeners reported a utilization problem that they were often unable to extract the meaning out of the message even if they had understood all the words. On the other hand, low ability listeners reported another perception problem that they often did not hear the next part of a text because they spent too much time thinking about what they had just heard.

Literature Survey on Hydrogen Separation Technique

Literature Survey on Hydrogen Separation Technique Literature review has been performed in order to identify recent publications on hydrogen separation methods, hydrogen solubility, materials and concepts in research institutes and laboratories. The aim of the performed literature survey was to monitor recent worldwide literature and find out whether some of the developed and reported solutions might possibly help to improve existing hydrogen separation concept in PDh system, enabling efficient complete separation of hydrogen from all unwanted hydrocarbons. Literature survey on hydrogen separation technique Basically there are four important methods applied to the separation of gases in the industry: absorption, adsorption, cryogenic and membranes. Pressure swing adsorption (PSA) is a gas purification process consisting of the removal of impurities on adsorbent beds. The usual adsorbents and gases adsorbed are molecular sieves for carbon monoxide, activated carbon for CO2, activated alumina or silica gel. Industrial PSA plants consist of up to 12 adsorbers and along with the number of valves required this makes the system rather complicated and complex. The PSA process is usually a repeating sequence of the following steps: adsorption at feed pressure, co-current depressurisation to intermediate pressure, counter-current depressurisation to atmospheric pressure usually starting at 10 % to 70 % of the feed pressure, counter-current purge with hydrogen enriched or product gas at ambient pressure, co-current pressure equalisation and finally, co-current pressurisation with feed or secondary process gas[1]. For hydrogen purification by PSA hydrogen purity is high but the amount of rejected hydrogen is also relatively high (10 †“ 35 %). It seems also that cryogenic technology might not be applicable for PDh process gas separation. Cooling down the mixture will finally end in a solid jet fuel and a gas phase. Handling the solid is more difficult when compared with liquid. During the survey it became evident that membrane technology is the most popular, used and still investigating for the improvement process for hydrogen separation therefore the focus of the study is mainly on this technique. The membrane separation process involves several elementary steps, which include the solution of hydrogen and its diffusion as atomic hydrogen through the membrane bulk material. Nowadays, membrane technologies are becoming more frequently used for separation of wide varying mixtures in the petrochemical related industries. According to Sutherland[2] it is estimated that bulk chemicals and petrochemicals applications represented about 40% of the membrane market in the whole chemicals industry or about $ 1.5 billions, growing over 5 % per year. Membrane gas separation is attractive because of its simplicity and low energy cost. The advantages of using membrane gas separation technologies could be summarized as following: Continuous and clean process, membranes do not require regeneration, unlike the adsorption or the absorption processes, which require regeneration step leading to the use of two solid beds or a solvent regeneration unit. Required filtration system is simple and inexpensive. Compared with conventional techniques, membranes can offer a simple, easy-to-operate, low-maintenance process. Membrane process is simple, generally carried out at atmospheric conditions which, besides being energy efficient, can be important for sensitive applications in pharmaceutical and food industry. The recovery of components from a main stream using membranes can be done without substantial additional energy costs. Membrane is defined essentially as a barrier, which separates two phases and restricts transport of various chemicals in a selective manner. A membrane can be homogenous or heterogeneous, symmetric or asymmetric in structure, solid or liquid; can carry a positive or negative charge or be neutral or bipolar. Transport through a membrane can be affected by convection or by diffusion of individual molecules, induced by an electric field or concentration, pressure or temperature gradient. It takes place when a driving force is applied to the components in the feed. In most of the membrane processes, the driving force is a pressure difference or a concentration (or activity) difference across the membrane. Another driving force in membrane separations is the electrical potential difference. This driving force only influences the transport of charged particles or molecules. The hydrogen separation factor is sometimes used to specify membrane quality. It is defined as following: where ni stands for moles of species i transferred through the membrane and ?pi stands for the partial pressure difference of species i through the membrane. The membrane thickness may vary from as small as 10 microns to few hundred micrometers. Basic types of membranes are presented in Figure 4. Membranes in petrochemical industry are mainly used for concentration, purification and fractionation however they may be coupled to a chemical reaction to shift the chemical equilibrium in a combination defined as a membrane reactor. Using a membrane is adding costs to any process, therefore in order to overcome the cost issue another advantages must overcome the added expenses like material with a very good separation factor, high flux, high quality membrane materials (stable during many months of operation). In a membrane separation reactor both organic and inorganic membranes can be used. Many industrial catalytic processes involve the combination of high temperature and chemically harsh environments favouring therefore inorganic membranes due to their thermal stability, resistance to organic solvents, chlorine and other chemicals. Some promising applications using inorganic membranes include certain dehydrogenation, hydrogenation and oxidation reactions like formation of butane from dehydrogenation of ethyl benzene, styrene production from dehydrogenation of ethyl benzene, dehydrogenation of ethane to ethane, oxidative coupling of methane etc. In membrane reactor two basic concepts can be distinguished as can be seen in Figure 5. reaction and separation combined in one reactor (catalytic membrane reactor) reaction and separation are not combined and the reactants are recycled along a membrane system (membrane recycle reactor) Catalytic membrane reactor concept is used especially with inorganic membranes (ceramics, metals) and polymeric membranes where the catalyst is coupled to the membrane. Membrane recycle reactor can be applied with any membrane process and type of membranes. Most of the chemical reactions need catalyst to enhance the reaction kinetics. The catalyst must be combined with the membrane system and various arrangements are possible, as can be seen in Figure 6. The advantage of the catalyst located inside the bore of the tube is simplicity in preparation and operation. When needed the catalyst could be easily replaced. In case of top layer filled with catalyst and membrane wall, the catalyst is immobilized onto the membrane. Palladium has been known to be a highly hydrogen permeable and selective material since the 19th century. The existing Pd-based membranes can be mainly classified into two types according to the structure of the membrane as (i) self-supporting Pd-based membranes and (ii) composite structures composed of thin Pd-based layers on porous materials. Most self-supporting Pd-based membranes are commercially available in the forms that are easily integrated into a separation setup. However these membranes are relatively thick (50 mm or more) and therefore the hydrogen flux through them is limited. Thick palladium membranes are expensive and rather suitable for use in large scale chemical production. For practical use it is necessary to develop separation units with reduced thickness of the layer. An additional problem is that in order to have adequate mechanical strength, relatively thick porous supports have to be used. In the last decade a significant research has been carried out to achie ve higher fluxes by depositing thin layers of Pd or Pd alloys on porous supports like ceramics or stainless steel. A submicron thick and defect-free palladium-silver (Pd-Ag) alloy membrane was fabricated on a supportive microsieve by using microfabrication technique and tested by Tong et al[4]. The technique also allowed production of a robust wafer-scale membrane module which could be easily inserted into a membrane holder to have gas-tight connections to outside. Fabricated membrane had a great potential for hydrogen purification and in application like dehydrogenation industry. One membrane module was investigated for a period of ca. 1000 hours during which the membrane experienced a change in gas type and its concentration as well as temperature cycling between 20 – 450  °C. The measured results showed no significant reduction in flux or selectivity, suggesting thus very good membrane stability. The authors carried out experiments with varying hydrogen concentration in the feed from 18 to 83 kPa at 450  °C to determine the steps limiting H2 transport rate. It is assumed that the fabricated membrane may be used as a membrane reactor for dehydrogenation reactions to synthesize high value products although its use may be limited due to high pressures of tens of bars. Schematic drawing of the hydrogen separation setup is presented in Figure 7. The membrane module was placed in a stainless steel holder installed in a temperature controlled oven to ensure isothermal operation. The H2/He feed (from 300 to 100 ml/mol) was preheated in spirals placed in the same oven. The setup was running automatically for 24 h/day and could handle 100 recipes without user intervention. Tucho et al.[5] performed microstructural studies of self-supported Pd / 23 wt. % Ag hydrogen separation membranes subjected to different heat treatments (300/400/450  °C for 4 days) and then tested for hydrogen permeation. It was noted that changes in permeability were dependent on the treatment atmosphere and temperature as well as membrane thickness. At higher temperatures significant grain growth was observed and stress relaxation occurred. Nam et al.[6] were able to fabricate a highly stable palladium alloy composite membrane for hydrogen separation on a porous stainless steel support by the vacuum electrodeposition and laminating procedure. The membrane was manufactured without microstructural change therefore it was possible to obtain both high performance (above 3 months of operation) and physical and morphological stability of the membrane. It was observed that the composite membrane had a capability to separate hydrogen from gas mixture with complete hydrogen selectivity and could be used to produce ultra-pure hydrogen for applications in membrane reactor. Tanaka et al.[7] aimed at the improved thermal stability of mesoporous Pd-YSZ-g-Al2O3 composite membrane. The improved thermal stability allowed operation at elevated temperature (> 500  °C for 200 hours). This was probably the result of improved fracture toughness of YSZ-g-Al2O3 layer and matching thermal expansion coefficient between palladium and YSZ. Kuraoka, Zhao and Yazawa[8] demonstrated that pore-filled palladium glass composite membranes for hydrogen separation prepared by electroless plating technique have both higher hydrogen permeance, and better mechanical properties than unsupported Pd films. The same technique was applied by Paglieri et al.[9] for plating a layer of Pd and then copper onto porous ?-substrate. Zahedi et al.[10] developed a thin palladium membrane by depositing Pd onto a tungsten oxide WO3 modified porous stainless steel disc and reported that permeability measureme nts at 723, 773 and 823 K showed high permeability and selectivity for hydrogen. The membrane was stable with regards to hydrogen for about 25 days. Certain effort has been performed for improving hydrothermal stability and application to hydrogen separation membranes at high temperatures. Igi et al.[11] prepared a hydrogen separation microporous membranes with enhanced hydrothermal stability at 500  °C under a steam pressure of 300 kPa. Co-doped silica sol solutions with varying Co composition (Co / (Si + Co) from 10 to 50 mol. %) were prepared and used for manufacturing the membranes. The membranes showed increased hydrothermal stability and high selectivity and permeability towards hydrogen when compared with pure silica membranes. The Co-doped silica membranes with a Co composition of 33 mol. % showed the highest selectivity for hydrogen, with a H2 permeance of 4.00 x 10-6 (m3 (STP) Ãâ€" (m Ãâ€" s Ãâ€" kPa)-1) and a H2/N2 permeance ratio of 730. It was observed that as the Co composition increased as high as 33 %, the activation energy of hydrogen permeation decreased and the H2 permeance increased. Additional increase in Co concentration resulted in increased H2 activation energy and decreased H2 permeance. Due to high permselectivity of Pd membranes, high purity of hydrogen can be obtained directly from hydrogen containing mixture at high temperatures without further purification providing if sufficient pressure gradient is applied. Therefore it is possible to integrate the reforming reaction and the separation step in a single unit. A membrane reformer system is simpler, more compact and more efficient than the conventional PSA system (Pressure Swing Adsorption) because stem reforming reaction of hydrocarbon fuels and hydrogen separation process take place in a single reactor simultaneously and without a separate shift converter and a purification system. Gepert et al.[12] have aimed at development of heat-integrated compact membrane reformer for d ecentralized hydrogen production and worked on composite ceramic capillaries (made of ?-Al2O3) coated with thin palladium membranes for production of CO-free hydrogen for PEM fuel cells by alcohol reforming. The membranes were tested for pure hydrogen and N2 as well as for synthetic reformate gas. The process steps comprised the evaporation and overheating of the water/alcohol feed, water gas shift combined with highly selective hydrogen separation. The authors have focused on the step concerned with the membrane separation of hydrogen from the reforming mixture and on the challenges and requirements of that process. The challenges encountered with the development of capillary Pd membranes were as following: long term temperature and pressure cycling stability in a reformate gas atmosphere, the ability to withstand frequent heating up and cooling down to room temperature, avoidance of the formation of pin-holes during operation and the integration of the membranes into reactor housi ng. It was observed that palladium membranes should not be operated at temperatures below 300  °C and pressures lower than 20 bar, while the upper operating range is between 500 and 900  °C. Alloying the membrane with copper and silver extend their operating temperature down to a room temperature. The introduction of silver into palladium membrane increases the lifetime, but also the costs when compared with copper. Detailed procedure of membrane manufacturing, integration into reformer unit and testing is described by the authors. Schematic of the concept of the integrated reformer is shown in Figure 8. The membrane was integrated in a metal tube embedded in electrically heated copper plates. Before entering the test tube, the gases were preheated to avoid local cooling of the membrane. Single gas measurements with pure N2 and H2 allowed the testing of the general performance of the membrane and the permselectivity for the respective gases to be reached. Synthetic reformate gas consisting of 75 % H2, 23.5 % CO2 and 1.5 % CO was used to get information about the performance. The membranes were tested between 370 – 450  °C and pressures up to 8 bar. The authors concluded that in general the membranes have shown good performance in terms of permeance and permselectivity including operation under reformate gas conditions. However, several problems were indicated concerning long-term stability under real reforming conditions, mainly related to structural nature (combination of different materials: ceramic, glaze, palladium resulted on incoherent potential for causing membrane failure). At operation times up to four weeks the continuous Pd layer remained essentially free from defects and pinholes. Han et al.[13] have developed a membrane separation module for a power equivalent of 10 kWel. A palladium membrane containing 40 wt. % copper and of 25 mm thickness was bonded into a metal frame. The separation module for a capacity of 10 Nm3 h-1 of hydrogen had a diameter of 10.8 cm and a length of 56 cm. Reformate fed to the modules contained 65 vol. % of hydrogen and the hydrogen recovery through the membrane was in the range of 75 %. Stable operation of the membrane separation was achieved for 750 pressure swing tests at 350  °C. The membrane separation device was integrated into a methanol fuel processor. Pientka et al.[14] have utilized a closed-cell polystyrene foam (Ursa XPS NIII, porosity 97 %) as a membrane buffer for separation of (bio)hydrogen. In the foam the cell walls formed a structured complex of membranes. The cells served as pressure containers of separated gases. The foam membrane was able to buffer the difference between the feed injection rate and the rate of consumption of the product. Using the difference in time-lags of different gases in polymeric foam, efficient gas separation was achieved during transient state and high purity hydrogen was obtained. Argonne National Laboratory (ANL) is involved in developing dense hydrogen-permeable membranes for separating hydrogen from mixed gases, particularly product streams during coal gasification and/or methane reforming. Novel cermet (ceramic-metal composite) membranes have been developed. Hydrogen separation with these membranes is non-galvanic (does not use electrodes or external power supply to drive the separation and hydrogen selectivity is nearly 100 % because the membrane contain no interconnected porosity). The membrane development at ANL initially concentrated on a mixed proton/electron conductor based on BaCe0.8Y0.2O3-d (BCY), but it turned to be insufficient to allow high non-galvanic hydrogen flux. To increase the electronic conductivity and thereby to increase the hydrogen flux the development focused on various cermet membranes with 40-50 vol. % of metal or alloy dispersed in the ceramic matrix. Balachandran et al.[15],[16] described the development performed at ANL. The powder mixture for fabricating cermet membranes was prepared by mechanical mixing Pd (50 vol. %) with YSZ, after that the powder mixture was pressed into discs. Polished cermet membranes were affixed to one end of alumina tube using a gold casket for a seal (as can be seen in Figure 9). In order to measure the hydrogen permeation rate, the alumina tube was inserted into a furnace with a sealed membrane and the associated gas flow tubes. Hydrogen permeation rate for Pd/YSZ membranes has been measured as a function of temperature (500-900  °C), partial pressure of hydrogen in the feed stream (0.04-1.0 atm.) and membrane thickness ( » 22-210 mm) as well as versus time during exposure to feed gases containing H2, CO, CO2, CH4 and H2S. The highest hydrogen flux was  » 20.0 cm3 (STP)/min cm2 for  » 22- mm thick membrane at 900  °C using 100 % hydrogen as the feed gas. These results suggested that membranes with thickness In the last decade Matrimid 5218 (Polyimide of 3,3,4,4-benzophenone tetracarboxylic dianhydride and diamino-phenylindane) has attracted a lot of attention as a material for gas separation membranes due to the combination of relatively high gas permeability coefficients and separation factors combined with excellent mechanical properties, solubility in non-hazard organic solvents and commercial availability. Shishatskiy et al.[18] have developed asymmetric flat sheet membranes for hydrogen separation from its mixtures with other gases. The composition and conditions of membrane preparation were optimized for pilot scale membrane production. The resulting membrane had a high hydrogen flux (1 m3 (STP)/m2h*bar) and selectivity of H2/CH4 at least 100, close to the selectivity of Matrimid 5218, material used for asymmetric structure formation. The hydrogen flux through the membranes increased with the decrease of polymer concentration and increase of non-solvent concentration. In addition, the influence of N2 blowing over the membrane surface (0, 2, 3, 4 Nm3 h-1 flow rate) was studied and it was proved that the selectivity of the membrane decreased with increase of the gas flow. The SEM image of the membrane supported by Matrimid 5218 is shown in Figure 10. The stability against hydrocarbons was tested by immersion of the membrane into the mixture of n-pentane/n-hexane/toluene in 1:1:1 ratio. Stability tests showed that the developed membrane was stable against mixtures of liquid hydrocarbons and could withstand continuous heating up to 200  °C for 24 and 120 hours and did not lose gas separation properties after exposure to a mixture of liquid hydrocarbons. The polyester non-woven fabric used as a support for the asymmetric membrane gave to the membrane excellent mechanical properties and allowed to use the membrane in gas separation modules. Interesting report on development of compact hydrogen separation module called MOC (Membrane On Catalyst) with structured Ni-based catalyst for use in the membrane reactor was presented by Kurokawa et al[19]. In the MOC concept a porous support itself had a function of reforming catalyst in addition to the role of membrane support. The integrated structure of support and catalyst made the membrane reformer more compact because the separate catalysts placed around the membrane modules in the conventional membrane reformers could be eliminated. In that idea first a porous catalytic structure 8YSZ (mixture of NiO and 8 mol. % Y2O3-ZrO2 at the weight ratio 60:40) was prepared as the support structure of the hydrogen membrane. The mixture was pressed into a tube closed at one end and sintered then in air. Slurry of 8YSZ was coated on the external surface of the porous support and heat-treated for alloying. Obtained module of size 10 mm outside and 8 mm inside diameter, 100 ~ 300 mm length and the membrane thickness was 7 ~ 20 mm were heated in flowing hydrogen at 600  °C for 3 hours to reduce NiO in the support structure into Ni before use (the porosity of the support after reduction was 43 %). A stainless steel cap and pipe were bonded to the module to introduce H2 into the inside of the tubular module. Figure 11 presents the conceptual structure design of the MOC module as compared with the structure of the conventional membrane reformer. The sample module in the reaction chamber was placed in the furnace and heated at 600  °C, pre-heated hydrogen (or humidified methane) was supplied inside MOC at the pressure of 0.1 MPa and the permeated hydrogen was collected from the outside chamber around the module at ambient pressure. The 100 ~ 300 mm long modules with 10 mm membrane showed hydrogen flux of 30 cm3 per minute per cm2 which was two times higher than the permeability of the conventional modules with palladium based alloy films. Membrane On Catalyst modules have a great potential to be applied to membrane reformer systems. In this concept a porous support itself has a function of reforming catalyst in addition to the role of membrane support. It seems that Membrane On Catalyst modules have a great potential to be applied to membrane reformer systems. Amorphous alloy membranes composed primarily of Ni and early transition metals (ETM) are an inexpensive alternative to Pd-based alloy membranes, and these materials are therefore of particular interest for the large-scale production of hydrogen from carbon-based fuels. Catalytic membrane reactors can produce hydrogen directly from coal-derived synthesis gas at 400 °C, by combining a commercial water-gas shift (WGS) catalyst with a hydrogen-selective membrane. Three main classes of membrane are capable of operating at the high temperatures demanded by existing WGS catalysts: ceramic membranes producing pure hydrogen via ion-transfer mechanism at  ³ 600  °C, alloy membranes which produce pure hydrogen via a solution-diffusion mechanism between 300 – 500  °C and microporous membranes, typically silica or carbon, whose purity depends on the pore size of the membrane and which operate over a wide temperature range dependent on the membrane material. In order to explore the suitability of Ni-based amorphous alloys for this application, the thermal stability and hydrogen permeation characteristics of Ni-ETM amorphous alloy membranes has been examined by Dolan et al[20]. Fundamental limitation of these materials is that hydrogen permeability is inversely proportional to the thermal stability of the alloy. Alloy design is therefore a compromise between hydrogen production rate and durability. Amorphous Ni60Nb(40-x)Zr(x) membranes have been tested at 400 °C in pure hydrogen, and in simulated coal-derived gas streams with high steam, CO and CO2 levels, without severe degradation or corrosion-induced failure. The authors have concluded that Ni-Nb-Zr amorphous alloys are therefore prospective materials for use in a catalytic membrane reactor for coal-derived syngas. Much attention has been given to inorganic materials such as zeolite, silica, zirconia and titania for development of gas- and liquid- separation membranes because they can be utilized under har sh conditions where organic polymer membranes cannot be applied. Silica membranes have been studied extensively for the preparation of various kinds of separation membranes: hydrogen, CO2 and C3 isomers. Kanezeashi[21] have proposed silica networks using an organo-inorganic hybrid alkoxide structure containing the organic groups between two silicon atoms, such as bis(triethoxysilyl)ethane (BTESE) for development of highly permeable hydrogen separation membranes with hydrothermal stability. The concept for improvement of hydrogen permeability of silica membrane was to design a loose-organic-inorganic hybrid silica network using mentioned BTESE (to shift the silica networks to a larger pore size for an increase in H2 permeability). A hybrid silica layer was prepared by coating a silica-zirconia intermediate layer with a BTESE polymer sol followed by drying and calcination at 300 °C in nitrogen. A thin, continuous separation layer of hybrid silica for selective H2 permeation was observed on top of the SiO2-ZrO2 intermediate layer as presented in Figure 12. Hybrid silica membranes showed a very high H2 permeance, ~ 1 order of magnitude higher (~ 10-5 mol m-2 s-1 Pa-1) than previously r eported silica membranes using TEOS (Tetraethoxysilane). The hydrothermal stability of the hybrid silica membranes due to the presence of Si-C-C-Si bonds in the silica networks was also confirmed. Nitodas et al.[22] for the development of composite silica membranes have used the method of chemical vapour deposition (CVD) in the counter current configuration from TEOS and ozone mixtures. The experiments were conducted in a horizontal hot-wall CVD quartz reactor (Figure 13) under controlled temperature conditions (523 – 543 K) and at various reaction times (0 -15 hours) and differential pressures across the substrate sides using two types of substrates: a porous Vycor tube and alumina (g-Al2O3) nanofiltration (NF) tube. The permeance of hydrogen and other gases (He, N2, Ar, CO2) were measured in a home-made apparatus (able to operate under high vacuum conditions 10-3 Torr, feed pressure up to 70 bar) and the separation capability of the composite membranes was determined by calculating the selectivity of hydrogen over He, N2, Ar, CO2. The in-situ monitoring of gas permeance during the CVD development of nanoporous membranes created a tool to detect pore size alterations i n the micro to nanometer scale of thickness. The highest permeance values in both modified and unmodified membranes are observed for H2 and the lowest for CO2. This indicated that the developed membranes were ideal candidates for H2/CO2 separations, like for example in reforming units of natural gas and biogas (H2/CO2/CO/CH4). Moon et al.[23] have studied the separation characteristics and dynamics of hydrogen mixture produced from natural gas reformer on tubular type methyltriethoxysilane (MTES) silica / ?-alumina composite membranes. The permeation and separation of CO pure gas, H2/CO (50/50 vol. %) binary mixture and H2/CH4/CO/CO2 (69/3/2/26 vol. %) quaternary mixture was investigated. The authors developed a membrane process suitable for separating H2 from CO and other reformate gases (CO2 or CH4) that showed a molecular sieving effect. Since the permeance of pure CO on the MTES membrane was very low (CO  » 4.79 – 6.46 x 10-11 mol m-2 s-1 Pa-1), comparatively high hydrogen selectivity could be obtained from the H2/CO mixture (separation factor: 93 – 110). This meant that CO (which shall be eliminated before entering fuel cell) can be separated from hydrogen mixtures using MTES membranes. The permeance of the hydrogen quaternary mixture on MTES membrane was 2.07 – 3.37 x 10-9 mol m-2 s-1 Pa-1 and the separation factor of H2 / (CO + CH4 + CO2) was 2.61 – 10.33 at 323 – 473 K (Figure 14). The permeation and selectivity of hydrogen were increased with temperature because of activation of H2 molecules and unfavourable conditions for CO2 adsorption. Compared to other impurities, CO was most successfully removed from the H2 mixture. The MTES membranes showed great potential for hydrogen separation from reforming gas with high selectivity and high permeance and therefore they have good potential for fuel cell systems and for use in hydrogen stations. According to the authors, the silica membranes are expected to be used for separating hydrogen in reforming environment at high temperatures. Silica membranes prepared by the CVD or sol-gel methods on mesoporous support are effective for selective hydrogen permeation, however it is known that hydrogen-selective silica materials are not thermally stable at high temperatures. Most researchers reported a loss of permeability of silica membranes even 50 % or greater in the first 12 hours on exposure to moisture at high temperature. Much effort has been spent on the improvement of the stability of silica membranes. Gu et al.[24] have investigated a hydrothermally stable and hydrogen-selective membrane composed of silica and alumina prepared on a macroporous alumina support by CVD in an inert atmosphere at high temperature. Before the deposition of the silica-alumina composite multiple graded layers of alumina were coated on the alumina support with three sols of decreasing particle sizes. The resulting supported composite silica-alumina membrane had high permeability for hydrogen (in the order of 10-7 mol m-2 s-1 Pa-1) at 873 K . Significantly the composite membrane exhibited much higher stability to water vapour at the high temperature of 873 K in comparison to pure silica membranes. The introduction of alumina into silica made the silica structure more stable and slowed down the silica disintegration process. As mentioned, silica membranes produced by sol-gel technique or by CVD applied for gas separation, especially for H2 production are quite stable in dry gases and exhibit high separation ratio, but lose the permeability when used in the steamed gases because of sintering or tightening. Thi Literature Survey on Hydrogen Separation Technique Literature Survey on Hydrogen Separation Technique Literature review has been performed in order to identify recent publications on hydrogen separation methods, hydrogen solubility, materials and concepts in research institutes and laboratories. The aim of the performed literature survey was to monitor recent worldwide literature and find out whether some of the developed and reported solutions might possibly help to improve existing hydrogen separation concept in PDh system, enabling efficient complete separation of hydrogen from all unwanted hydrocarbons. Literature survey on hydrogen separation technique Basically there are four important methods applied to the separation of gases in the industry: absorption, adsorption, cryogenic and membranes. Pressure swing adsorption (PSA) is a gas purification process consisting of the removal of impurities on adsorbent beds. The usual adsorbents and gases adsorbed are molecular sieves for carbon monoxide, activated carbon for CO2, activated alumina or silica gel. Industrial PSA plants consist of up to 12 adsorbers and along with the number of valves required this makes the system rather complicated and complex. The PSA process is usually a repeating sequence of the following steps: adsorption at feed pressure, co-current depressurisation to intermediate pressure, counter-current depressurisation to atmospheric pressure usually starting at 10 % to 70 % of the feed pressure, counter-current purge with hydrogen enriched or product gas at ambient pressure, co-current pressure equalisation and finally, co-current pressurisation with feed or secondary process gas[1]. For hydrogen purification by PSA hydrogen purity is high but the amount of rejected hydrogen is also relatively high (10 †“ 35 %). It seems also that cryogenic technology might not be applicable for PDh process gas separation. Cooling down the mixture will finally end in a solid jet fuel and a gas phase. Handling the solid is more difficult when compared with liquid. During the survey it became evident that membrane technology is the most popular, used and still investigating for the improvement process for hydrogen separation therefore the focus of the study is mainly on this technique. The membrane separation process involves several elementary steps, which include the solution of hydrogen and its diffusion as atomic hydrogen through the membrane bulk material. Nowadays, membrane technologies are becoming more frequently used for separation of wide varying mixtures in the petrochemical related industries. According to Sutherland[2] it is estimated that bulk chemicals and petrochemicals applications represented about 40% of the membrane market in the whole chemicals industry or about $ 1.5 billions, growing over 5 % per year. Membrane gas separation is attractive because of its simplicity and low energy cost. The advantages of using membrane gas separation technologies could be summarized as following: Continuous and clean process, membranes do not require regeneration, unlike the adsorption or the absorption processes, which require regeneration step leading to the use of two solid beds or a solvent regeneration unit. Required filtration system is simple and inexpensive. Compared with conventional techniques, membranes can offer a simple, easy-to-operate, low-maintenance process. Membrane process is simple, generally carried out at atmospheric conditions which, besides being energy efficient, can be important for sensitive applications in pharmaceutical and food industry. The recovery of components from a main stream using membranes can be done without substantial additional energy costs. Membrane is defined essentially as a barrier, which separates two phases and restricts transport of various chemicals in a selective manner. A membrane can be homogenous or heterogeneous, symmetric or asymmetric in structure, solid or liquid; can carry a positive or negative charge or be neutral or bipolar. Transport through a membrane can be affected by convection or by diffusion of individual molecules, induced by an electric field or concentration, pressure or temperature gradient. It takes place when a driving force is applied to the components in the feed. In most of the membrane processes, the driving force is a pressure difference or a concentration (or activity) difference across the membrane. Another driving force in membrane separations is the electrical potential difference. This driving force only influences the transport of charged particles or molecules. The hydrogen separation factor is sometimes used to specify membrane quality. It is defined as following: where ni stands for moles of species i transferred through the membrane and ?pi stands for the partial pressure difference of species i through the membrane. The membrane thickness may vary from as small as 10 microns to few hundred micrometers. Basic types of membranes are presented in Figure 4. Membranes in petrochemical industry are mainly used for concentration, purification and fractionation however they may be coupled to a chemical reaction to shift the chemical equilibrium in a combination defined as a membrane reactor. Using a membrane is adding costs to any process, therefore in order to overcome the cost issue another advantages must overcome the added expenses like material with a very good separation factor, high flux, high quality membrane materials (stable during many months of operation). In a membrane separation reactor both organic and inorganic membranes can be used. Many industrial catalytic processes involve the combination of high temperature and chemically harsh environments favouring therefore inorganic membranes due to their thermal stability, resistance to organic solvents, chlorine and other chemicals. Some promising applications using inorganic membranes include certain dehydrogenation, hydrogenation and oxidation reactions like formation of butane from dehydrogenation of ethyl benzene, styrene production from dehydrogenation of ethyl benzene, dehydrogenation of ethane to ethane, oxidative coupling of methane etc. In membrane reactor two basic concepts can be distinguished as can be seen in Figure 5. reaction and separation combined in one reactor (catalytic membrane reactor) reaction and separation are not combined and the reactants are recycled along a membrane system (membrane recycle reactor) Catalytic membrane reactor concept is used especially with inorganic membranes (ceramics, metals) and polymeric membranes where the catalyst is coupled to the membrane. Membrane recycle reactor can be applied with any membrane process and type of membranes. Most of the chemical reactions need catalyst to enhance the reaction kinetics. The catalyst must be combined with the membrane system and various arrangements are possible, as can be seen in Figure 6. The advantage of the catalyst located inside the bore of the tube is simplicity in preparation and operation. When needed the catalyst could be easily replaced. In case of top layer filled with catalyst and membrane wall, the catalyst is immobilized onto the membrane. Palladium has been known to be a highly hydrogen permeable and selective material since the 19th century. The existing Pd-based membranes can be mainly classified into two types according to the structure of the membrane as (i) self-supporting Pd-based membranes and (ii) composite structures composed of thin Pd-based layers on porous materials. Most self-supporting Pd-based membranes are commercially available in the forms that are easily integrated into a separation setup. However these membranes are relatively thick (50 mm or more) and therefore the hydrogen flux through them is limited. Thick palladium membranes are expensive and rather suitable for use in large scale chemical production. For practical use it is necessary to develop separation units with reduced thickness of the layer. An additional problem is that in order to have adequate mechanical strength, relatively thick porous supports have to be used. In the last decade a significant research has been carried out to achie ve higher fluxes by depositing thin layers of Pd or Pd alloys on porous supports like ceramics or stainless steel. A submicron thick and defect-free palladium-silver (Pd-Ag) alloy membrane was fabricated on a supportive microsieve by using microfabrication technique and tested by Tong et al[4]. The technique also allowed production of a robust wafer-scale membrane module which could be easily inserted into a membrane holder to have gas-tight connections to outside. Fabricated membrane had a great potential for hydrogen purification and in application like dehydrogenation industry. One membrane module was investigated for a period of ca. 1000 hours during which the membrane experienced a change in gas type and its concentration as well as temperature cycling between 20 – 450  °C. The measured results showed no significant reduction in flux or selectivity, suggesting thus very good membrane stability. The authors carried out experiments with varying hydrogen concentration in the feed from 18 to 83 kPa at 450  °C to determine the steps limiting H2 transport rate. It is assumed that the fabricated membrane may be used as a membrane reactor for dehydrogenation reactions to synthesize high value products although its use may be limited due to high pressures of tens of bars. Schematic drawing of the hydrogen separation setup is presented in Figure 7. The membrane module was placed in a stainless steel holder installed in a temperature controlled oven to ensure isothermal operation. The H2/He feed (from 300 to 100 ml/mol) was preheated in spirals placed in the same oven. The setup was running automatically for 24 h/day and could handle 100 recipes without user intervention. Tucho et al.[5] performed microstructural studies of self-supported Pd / 23 wt. % Ag hydrogen separation membranes subjected to different heat treatments (300/400/450  °C for 4 days) and then tested for hydrogen permeation. It was noted that changes in permeability were dependent on the treatment atmosphere and temperature as well as membrane thickness. At higher temperatures significant grain growth was observed and stress relaxation occurred. Nam et al.[6] were able to fabricate a highly stable palladium alloy composite membrane for hydrogen separation on a porous stainless steel support by the vacuum electrodeposition and laminating procedure. The membrane was manufactured without microstructural change therefore it was possible to obtain both high performance (above 3 months of operation) and physical and morphological stability of the membrane. It was observed that the composite membrane had a capability to separate hydrogen from gas mixture with complete hydrogen selectivity and could be used to produce ultra-pure hydrogen for applications in membrane reactor. Tanaka et al.[7] aimed at the improved thermal stability of mesoporous Pd-YSZ-g-Al2O3 composite membrane. The improved thermal stability allowed operation at elevated temperature (> 500  °C for 200 hours). This was probably the result of improved fracture toughness of YSZ-g-Al2O3 layer and matching thermal expansion coefficient between palladium and YSZ. Kuraoka, Zhao and Yazawa[8] demonstrated that pore-filled palladium glass composite membranes for hydrogen separation prepared by electroless plating technique have both higher hydrogen permeance, and better mechanical properties than unsupported Pd films. The same technique was applied by Paglieri et al.[9] for plating a layer of Pd and then copper onto porous ?-substrate. Zahedi et al.[10] developed a thin palladium membrane by depositing Pd onto a tungsten oxide WO3 modified porous stainless steel disc and reported that permeability measureme nts at 723, 773 and 823 K showed high permeability and selectivity for hydrogen. The membrane was stable with regards to hydrogen for about 25 days. Certain effort has been performed for improving hydrothermal stability and application to hydrogen separation membranes at high temperatures. Igi et al.[11] prepared a hydrogen separation microporous membranes with enhanced hydrothermal stability at 500  °C under a steam pressure of 300 kPa. Co-doped silica sol solutions with varying Co composition (Co / (Si + Co) from 10 to 50 mol. %) were prepared and used for manufacturing the membranes. The membranes showed increased hydrothermal stability and high selectivity and permeability towards hydrogen when compared with pure silica membranes. The Co-doped silica membranes with a Co composition of 33 mol. % showed the highest selectivity for hydrogen, with a H2 permeance of 4.00 x 10-6 (m3 (STP) Ãâ€" (m Ãâ€" s Ãâ€" kPa)-1) and a H2/N2 permeance ratio of 730. It was observed that as the Co composition increased as high as 33 %, the activation energy of hydrogen permeation decreased and the H2 permeance increased. Additional increase in Co concentration resulted in increased H2 activation energy and decreased H2 permeance. Due to high permselectivity of Pd membranes, high purity of hydrogen can be obtained directly from hydrogen containing mixture at high temperatures without further purification providing if sufficient pressure gradient is applied. Therefore it is possible to integrate the reforming reaction and the separation step in a single unit. A membrane reformer system is simpler, more compact and more efficient than the conventional PSA system (Pressure Swing Adsorption) because stem reforming reaction of hydrocarbon fuels and hydrogen separation process take place in a single reactor simultaneously and without a separate shift converter and a purification system. Gepert et al.[12] have aimed at development of heat-integrated compact membrane reformer for d ecentralized hydrogen production and worked on composite ceramic capillaries (made of ?-Al2O3) coated with thin palladium membranes for production of CO-free hydrogen for PEM fuel cells by alcohol reforming. The membranes were tested for pure hydrogen and N2 as well as for synthetic reformate gas. The process steps comprised the evaporation and overheating of the water/alcohol feed, water gas shift combined with highly selective hydrogen separation. The authors have focused on the step concerned with the membrane separation of hydrogen from the reforming mixture and on the challenges and requirements of that process. The challenges encountered with the development of capillary Pd membranes were as following: long term temperature and pressure cycling stability in a reformate gas atmosphere, the ability to withstand frequent heating up and cooling down to room temperature, avoidance of the formation of pin-holes during operation and the integration of the membranes into reactor housi ng. It was observed that palladium membranes should not be operated at temperatures below 300  °C and pressures lower than 20 bar, while the upper operating range is between 500 and 900  °C. Alloying the membrane with copper and silver extend their operating temperature down to a room temperature. The introduction of silver into palladium membrane increases the lifetime, but also the costs when compared with copper. Detailed procedure of membrane manufacturing, integration into reformer unit and testing is described by the authors. Schematic of the concept of the integrated reformer is shown in Figure 8. The membrane was integrated in a metal tube embedded in electrically heated copper plates. Before entering the test tube, the gases were preheated to avoid local cooling of the membrane. Single gas measurements with pure N2 and H2 allowed the testing of the general performance of the membrane and the permselectivity for the respective gases to be reached. Synthetic reformate gas consisting of 75 % H2, 23.5 % CO2 and 1.5 % CO was used to get information about the performance. The membranes were tested between 370 – 450  °C and pressures up to 8 bar. The authors concluded that in general the membranes have shown good performance in terms of permeance and permselectivity including operation under reformate gas conditions. However, several problems were indicated concerning long-term stability under real reforming conditions, mainly related to structural nature (combination of different materials: ceramic, glaze, palladium resulted on incoherent potential for causing membrane failure). At operation times up to four weeks the continuous Pd layer remained essentially free from defects and pinholes. Han et al.[13] have developed a membrane separation module for a power equivalent of 10 kWel. A palladium membrane containing 40 wt. % copper and of 25 mm thickness was bonded into a metal frame. The separation module for a capacity of 10 Nm3 h-1 of hydrogen had a diameter of 10.8 cm and a length of 56 cm. Reformate fed to the modules contained 65 vol. % of hydrogen and the hydrogen recovery through the membrane was in the range of 75 %. Stable operation of the membrane separation was achieved for 750 pressure swing tests at 350  °C. The membrane separation device was integrated into a methanol fuel processor. Pientka et al.[14] have utilized a closed-cell polystyrene foam (Ursa XPS NIII, porosity 97 %) as a membrane buffer for separation of (bio)hydrogen. In the foam the cell walls formed a structured complex of membranes. The cells served as pressure containers of separated gases. The foam membrane was able to buffer the difference between the feed injection rate and the rate of consumption of the product. Using the difference in time-lags of different gases in polymeric foam, efficient gas separation was achieved during transient state and high purity hydrogen was obtained. Argonne National Laboratory (ANL) is involved in developing dense hydrogen-permeable membranes for separating hydrogen from mixed gases, particularly product streams during coal gasification and/or methane reforming. Novel cermet (ceramic-metal composite) membranes have been developed. Hydrogen separation with these membranes is non-galvanic (does not use electrodes or external power supply to drive the separation and hydrogen selectivity is nearly 100 % because the membrane contain no interconnected porosity). The membrane development at ANL initially concentrated on a mixed proton/electron conductor based on BaCe0.8Y0.2O3-d (BCY), but it turned to be insufficient to allow high non-galvanic hydrogen flux. To increase the electronic conductivity and thereby to increase the hydrogen flux the development focused on various cermet membranes with 40-50 vol. % of metal or alloy dispersed in the ceramic matrix. Balachandran et al.[15],[16] described the development performed at ANL. The powder mixture for fabricating cermet membranes was prepared by mechanical mixing Pd (50 vol. %) with YSZ, after that the powder mixture was pressed into discs. Polished cermet membranes were affixed to one end of alumina tube using a gold casket for a seal (as can be seen in Figure 9). In order to measure the hydrogen permeation rate, the alumina tube was inserted into a furnace with a sealed membrane and the associated gas flow tubes. Hydrogen permeation rate for Pd/YSZ membranes has been measured as a function of temperature (500-900  °C), partial pressure of hydrogen in the feed stream (0.04-1.0 atm.) and membrane thickness ( » 22-210 mm) as well as versus time during exposure to feed gases containing H2, CO, CO2, CH4 and H2S. The highest hydrogen flux was  » 20.0 cm3 (STP)/min cm2 for  » 22- mm thick membrane at 900  °C using 100 % hydrogen as the feed gas. These results suggested that membranes with thickness In the last decade Matrimid 5218 (Polyimide of 3,3,4,4-benzophenone tetracarboxylic dianhydride and diamino-phenylindane) has attracted a lot of attention as a material for gas separation membranes due to the combination of relatively high gas permeability coefficients and separation factors combined with excellent mechanical properties, solubility in non-hazard organic solvents and commercial availability. Shishatskiy et al.[18] have developed asymmetric flat sheet membranes for hydrogen separation from its mixtures with other gases. The composition and conditions of membrane preparation were optimized for pilot scale membrane production. The resulting membrane had a high hydrogen flux (1 m3 (STP)/m2h*bar) and selectivity of H2/CH4 at least 100, close to the selectivity of Matrimid 5218, material used for asymmetric structure formation. The hydrogen flux through the membranes increased with the decrease of polymer concentration and increase of non-solvent concentration. In addition, the influence of N2 blowing over the membrane surface (0, 2, 3, 4 Nm3 h-1 flow rate) was studied and it was proved that the selectivity of the membrane decreased with increase of the gas flow. The SEM image of the membrane supported by Matrimid 5218 is shown in Figure 10. The stability against hydrocarbons was tested by immersion of the membrane into the mixture of n-pentane/n-hexane/toluene in 1:1:1 ratio. Stability tests showed that the developed membrane was stable against mixtures of liquid hydrocarbons and could withstand continuous heating up to 200  °C for 24 and 120 hours and did not lose gas separation properties after exposure to a mixture of liquid hydrocarbons. The polyester non-woven fabric used as a support for the asymmetric membrane gave to the membrane excellent mechanical properties and allowed to use the membrane in gas separation modules. Interesting report on development of compact hydrogen separation module called MOC (Membrane On Catalyst) with structured Ni-based catalyst for use in the membrane reactor was presented by Kurokawa et al[19]. In the MOC concept a porous support itself had a function of reforming catalyst in addition to the role of membrane support. The integrated structure of support and catalyst made the membrane reformer more compact because the separate catalysts placed around the membrane modules in the conventional membrane reformers could be eliminated. In that idea first a porous catalytic structure 8YSZ (mixture of NiO and 8 mol. % Y2O3-ZrO2 at the weight ratio 60:40) was prepared as the support structure of the hydrogen membrane. The mixture was pressed into a tube closed at one end and sintered then in air. Slurry of 8YSZ was coated on the external surface of the porous support and heat-treated for alloying. Obtained module of size 10 mm outside and 8 mm inside diameter, 100 ~ 300 mm length and the membrane thickness was 7 ~ 20 mm were heated in flowing hydrogen at 600  °C for 3 hours to reduce NiO in the support structure into Ni before use (the porosity of the support after reduction was 43 %). A stainless steel cap and pipe were bonded to the module to introduce H2 into the inside of the tubular module. Figure 11 presents the conceptual structure design of the MOC module as compared with the structure of the conventional membrane reformer. The sample module in the reaction chamber was placed in the furnace and heated at 600  °C, pre-heated hydrogen (or humidified methane) was supplied inside MOC at the pressure of 0.1 MPa and the permeated hydrogen was collected from the outside chamber around the module at ambient pressure. The 100 ~ 300 mm long modules with 10 mm membrane showed hydrogen flux of 30 cm3 per minute per cm2 which was two times higher than the permeability of the conventional modules with palladium based alloy films. Membrane On Catalyst modules have a great potential to be applied to membrane reformer systems. In this concept a porous support itself has a function of reforming catalyst in addition to the role of membrane support. It seems that Membrane On Catalyst modules have a great potential to be applied to membrane reformer systems. Amorphous alloy membranes composed primarily of Ni and early transition metals (ETM) are an inexpensive alternative to Pd-based alloy membranes, and these materials are therefore of particular interest for the large-scale production of hydrogen from carbon-based fuels. Catalytic membrane reactors can produce hydrogen directly from coal-derived synthesis gas at 400 °C, by combining a commercial water-gas shift (WGS) catalyst with a hydrogen-selective membrane. Three main classes of membrane are capable of operating at the high temperatures demanded by existing WGS catalysts: ceramic membranes producing pure hydrogen via ion-transfer mechanism at  ³ 600  °C, alloy membranes which produce pure hydrogen via a solution-diffusion mechanism between 300 – 500  °C and microporous membranes, typically silica or carbon, whose purity depends on the pore size of the membrane and which operate over a wide temperature range dependent on the membrane material. In order to explore the suitability of Ni-based amorphous alloys for this application, the thermal stability and hydrogen permeation characteristics of Ni-ETM amorphous alloy membranes has been examined by Dolan et al[20]. Fundamental limitation of these materials is that hydrogen permeability is inversely proportional to the thermal stability of the alloy. Alloy design is therefore a compromise between hydrogen production rate and durability. Amorphous Ni60Nb(40-x)Zr(x) membranes have been tested at 400 °C in pure hydrogen, and in simulated coal-derived gas streams with high steam, CO and CO2 levels, without severe degradation or corrosion-induced failure. The authors have concluded that Ni-Nb-Zr amorphous alloys are therefore prospective materials for use in a catalytic membrane reactor for coal-derived syngas. Much attention has been given to inorganic materials such as zeolite, silica, zirconia and titania for development of gas- and liquid- separation membranes because they can be utilized under har sh conditions where organic polymer membranes cannot be applied. Silica membranes have been studied extensively for the preparation of various kinds of separation membranes: hydrogen, CO2 and C3 isomers. Kanezeashi[21] have proposed silica networks using an organo-inorganic hybrid alkoxide structure containing the organic groups between two silicon atoms, such as bis(triethoxysilyl)ethane (BTESE) for development of highly permeable hydrogen separation membranes with hydrothermal stability. The concept for improvement of hydrogen permeability of silica membrane was to design a loose-organic-inorganic hybrid silica network using mentioned BTESE (to shift the silica networks to a larger pore size for an increase in H2 permeability). A hybrid silica layer was prepared by coating a silica-zirconia intermediate layer with a BTESE polymer sol followed by drying and calcination at 300 °C in nitrogen. A thin, continuous separation layer of hybrid silica for selective H2 permeation was observed on top of the SiO2-ZrO2 intermediate layer as presented in Figure 12. Hybrid silica membranes showed a very high H2 permeance, ~ 1 order of magnitude higher (~ 10-5 mol m-2 s-1 Pa-1) than previously r eported silica membranes using TEOS (Tetraethoxysilane). The hydrothermal stability of the hybrid silica membranes due to the presence of Si-C-C-Si bonds in the silica networks was also confirmed. Nitodas et al.[22] for the development of composite silica membranes have used the method of chemical vapour deposition (CVD) in the counter current configuration from TEOS and ozone mixtures. The experiments were conducted in a horizontal hot-wall CVD quartz reactor (Figure 13) under controlled temperature conditions (523 – 543 K) and at various reaction times (0 -15 hours) and differential pressures across the substrate sides using two types of substrates: a porous Vycor tube and alumina (g-Al2O3) nanofiltration (NF) tube. The permeance of hydrogen and other gases (He, N2, Ar, CO2) were measured in a home-made apparatus (able to operate under high vacuum conditions 10-3 Torr, feed pressure up to 70 bar) and the separation capability of the composite membranes was determined by calculating the selectivity of hydrogen over He, N2, Ar, CO2. The in-situ monitoring of gas permeance during the CVD development of nanoporous membranes created a tool to detect pore size alterations i n the micro to nanometer scale of thickness. The highest permeance values in both modified and unmodified membranes are observed for H2 and the lowest for CO2. This indicated that the developed membranes were ideal candidates for H2/CO2 separations, like for example in reforming units of natural gas and biogas (H2/CO2/CO/CH4). Moon et al.[23] have studied the separation characteristics and dynamics of hydrogen mixture produced from natural gas reformer on tubular type methyltriethoxysilane (MTES) silica / ?-alumina composite membranes. The permeation and separation of CO pure gas, H2/CO (50/50 vol. %) binary mixture and H2/CH4/CO/CO2 (69/3/2/26 vol. %) quaternary mixture was investigated. The authors developed a membrane process suitable for separating H2 from CO and other reformate gases (CO2 or CH4) that showed a molecular sieving effect. Since the permeance of pure CO on the MTES membrane was very low (CO  » 4.79 – 6.46 x 10-11 mol m-2 s-1 Pa-1), comparatively high hydrogen selectivity could be obtained from the H2/CO mixture (separation factor: 93 – 110). This meant that CO (which shall be eliminated before entering fuel cell) can be separated from hydrogen mixtures using MTES membranes. The permeance of the hydrogen quaternary mixture on MTES membrane was 2.07 – 3.37 x 10-9 mol m-2 s-1 Pa-1 and the separation factor of H2 / (CO + CH4 + CO2) was 2.61 – 10.33 at 323 – 473 K (Figure 14). The permeation and selectivity of hydrogen were increased with temperature because of activation of H2 molecules and unfavourable conditions for CO2 adsorption. Compared to other impurities, CO was most successfully removed from the H2 mixture. The MTES membranes showed great potential for hydrogen separation from reforming gas with high selectivity and high permeance and therefore they have good potential for fuel cell systems and for use in hydrogen stations. According to the authors, the silica membranes are expected to be used for separating hydrogen in reforming environment at high temperatures. Silica membranes prepared by the CVD or sol-gel methods on mesoporous support are effective for selective hydrogen permeation, however it is known that hydrogen-selective silica materials are not thermally stable at high temperatures. Most researchers reported a loss of permeability of silica membranes even 50 % or greater in the first 12 hours on exposure to moisture at high temperature. Much effort has been spent on the improvement of the stability of silica membranes. Gu et al.[24] have investigated a hydrothermally stable and hydrogen-selective membrane composed of silica and alumina prepared on a macroporous alumina support by CVD in an inert atmosphere at high temperature. Before the deposition of the silica-alumina composite multiple graded layers of alumina were coated on the alumina support with three sols of decreasing particle sizes. The resulting supported composite silica-alumina membrane had high permeability for hydrogen (in the order of 10-7 mol m-2 s-1 Pa-1) at 873 K . Significantly the composite membrane exhibited much higher stability to water vapour at the high temperature of 873 K in comparison to pure silica membranes. The introduction of alumina into silica made the silica structure more stable and slowed down the silica disintegration process. As mentioned, silica membranes produced by sol-gel technique or by CVD applied for gas separation, especially for H2 production are quite stable in dry gases and exhibit high separation ratio, but lose the permeability when used in the steamed gases because of sintering or tightening. Thi