Cathay Pacific Airlines Essay Example | Topics and Well Written Essays - 4000 words

Cathay Pacific Airlines - Essay Example It is with regards to this fact that the research has endeavored to conduct a thorough analysis of the STP strategies that have been adopted by Cathay Pacific Airlines till date. This allowed the researcher to analyze the effectiveness of these strategies as far as adding customer value is concerned. This analysis has been grounded on the basis of situation evaluation that enabled the researcher to explain the environment (both macro and micro) in which Cathay Pacific has been operating. By doing so, the researcher was able to justify the strategies adopted by the airline in accordance with the macro as well as microenvironment within which the company operates. The nature of this research is purely qualitative in nature where the researcher has attempted to analyze secondary information that is available over different scholarly journals, online databases and other websites relevant to the company of choice. The conclusions and recommendations pertaining to the research have been st ated accordingly. It is a widely known fact that the world of business is an ever-changing environment. In such an intensely competitive environment, a leading business sometimes fails to maintain its position as the market leader as a result of inappropriateness in terms of adapting to the dynamic world (G. T. Haley, U. C. Haley, and Tan, 2012; Markus and Loebbecke, 2013). There are certain exceptions where companies adopt prudent strategies that provide them with the necessary ammunition to stay ahead in the race. One such company is the Hong Kong-based airline and cargo carrier, Cathay Pacific. The company has long been known to adopt and implement proper strategies which have helped the organizational managers to compete with the likes of airline giants such as Air China, Singapore Airlines, Dragon Air, Emirates and Lufthansa (CAPA Centre for Aviation, 2014). World leaders and academic scholars have been noted praising the market strategies in particular adopted by the company that has enhanced it s competency in this fiercely competitive industry.

Orangic Milk or Regular Milk Essay Example for Free

Orangic Milk or Regular Milk Essay Is organic milk really that better for you? That was what I was thinking when we were discussing that in health class. Coach Deyo gave good ideas, but I still had my doubts. Because people have been drinking regular milk a long time and no one has died from it or didn’t get enough nutrients from it. So, why do people say organic milk is better for you. I was looking at a website called Men’s Health. It gives a few ideas about organic milk and regular milk. One thing said on the website made me think, why waste the money on organic milk if it doesn’t give you the effects you desire. â€Å"There are differences between organic and conventional milk production, but they may not have the effects consumers expect, says Thomas Overton, Ph. D. , associate professor of animal science at Cornell University. † After I read this I was thinking maybe it’s all in the consumers mind that organic is better for them. Maybe that’s what the organic milk farms want them to think. The website also states that you get the same stuff from organic milk in regular milk. â€Å"For one thing, it’s not any healthier. â€Å"An eight-ounce serving of regular milk offers the same nine essential nutrients—including calcium, vitamin D, and potassium—as a glass of organic milk,† Mangieri says. † So, people that say they drink organic milk because it’s healthier for you are not correct, it’s basically the same type of milk just the cows are feed differently. This is what I read that gave me that idea that the organic dairy cows are just fed differently than the regular milk cows. â€Å"Are fed only organic grains, free of synthetic fertilizers and pesticides; get at least 30 percent of their feed from pasture; aren’t treated with antibiotics, or with bovine growth hormone to increase milk production. † The website was talking about how organic dairy farms feed and treat their cows. In my opinion, that’s a good thing that they are being fed organic grains and not treated with growth hormones. But, why does it matter if it’s going to be the same kind of nutrients. Also I read in the website that both types of dairy farms have to go through a test for antibiotic residue. â€Å"There’s also no distinction in terms of unwanted ingredients. All organic and conventional milk is tested for antibiotic residue, and any milk that contains it is removed from the food supply. † In conclusion I think it’s all up to the consumer. If the consumer wants healthier milk for him or her, you could decide between both milks. If the consumer wants milk from a cow that’s fed and treated right then they should decide to get organic milk. But for me if I drank milk, I would decide to pick the one that gives you the nutrients you need and not break my wallet.

A Place That Is Important to Me Essay Example for Free

A Place That Is Important to Me Essay I have lived in Bunbury for 15years. My family has occupied the house in which I live for 10years. I have two sisters and two brothers. I am the middle child. I have always felt that my home has been an important place to me. I have countless memories held within these walls, and almost all of them are positive. Home to me, has always been the roof above my head. Recently though, when my elder sister moved out, I have been lost by what home truly means. If I no longer feel a sense of home under my roof, then where is my home? I try to answer this by thinking about the places that are important to me. As I do this I come to the realization that there is no one particular location that screams of an overwhelming importance to me. I have a myriad list of locations that I have felt some form of emotional connection with. But does this mean that all these places are a home to me? Where is my home? Important places to me are those that you don’t think you could live without. When I think of a soccer field, a dancing stage, or a couch to simply lie and have movie marathons on, I don’t think about the location, I think about the people involved in the memories created there. These places are important to me, not because they themselves are important, but because of the amazing memories I have experienced there. So if I were asked if I could live without these places, I would say no. But does that make them all a home to me? And if not, where is my home? Maybe home truly is where the heart is. A phrase I have always thought to be corny, but now however I see some form of factual meaning behind. Home to me is all about that sense of security and love. Knowing that you are wanted. So does this feeling necessarily have to come from a particular location? Could it not be found simply by doing something, or being with someone? And if home can really not be about the walls around you, where is my home? I try to think about when I’ve been my happiest, my safest, when I’ve felt unbelievably accepted and appreciated. I can only here say with complete honesty that I think of my sister. I think of all the fun and laughs we’ve had together. I think about how I feel every time I get to see her, and how I feel every time I have to say goodbye. I’ve come to realize that without her ever-bubbly presence in my life I have changed a lot. I believe that we, as humans, never purposefully change. We simply adjust to new things, and without realizing it we find new people to help us breathe. These people fill me with the utmost joy and security. These people are my home. An important place to me is my home. To have that sense of belonging, and know that there is always someone there to take care of you. That is my home. I have learnt how to cope without my sister, even though it proves hard at times, I have learnt to cope. For as hard as it is to know that she’s not around, I know other people will be. And that’s all I need. That sense of place, to know that no matter where I am or who I’m with, I am loved for myself. That’s what’s important.

History and Properties of Rubber

History and Properties of Rubber History of Rubber Rubber was first discovered by the Indians living in Central and South America at around 1000 CE. The native people of the Americas used latex from the rubber trees (which they called it the cahuchu tree) and learned how to make waterproof clothes and footwears.1 They also used the latex to make bouncing balls for ball games.1 In 1736, a French explorer named Charles Marie de La Condamine travelled to Ecuador and discovered the Hevea tree (which is known as the rubber tree), he was the first European to have discovered rubber. He sent samples of this rubber to the French Academy of Sciences, this prompted their interest of rubber.2 Figure 1: Latex liquid collected from the Hevea rubber tree 3 In 1770, English engineer named Edward Nairne created several rubber cubes and discovered that they had erasing properties. This meant that they can be able to erase pencil marks, this was later confirmed by English scientist named Joseph Priestley.4 In 1768, a French Chemist named Pierre Macquer studied the properties of the rubber found in South America. He found that when rubber is dissolved in ether, flexible tubes can be produced 5, this has led to rubber being an important material to many everyday applications. In 1791, a British shoemaker named Samuel Peal developed a method for waterproofing cloth, this was done by mixing turpentine (which is an oiled that is attained by the distillation of resin from pine trees) with rubber.6 In 1818, a Scottish surgeon named James Syme manufactured raincoats from waterproof cloth made from rubber.7 This was then later developed by Scottish chemist named Charles Macintosh. In 1823, he developed a method of making better waterproof raincoats by dissolving rubber with naphtha (which is an oil attained by the distillation of coal tar) and then placing it with another cloth (in order to improve the thickness of the coat). The waterproof coat became known as the Mackintosh coat.8 Figure 2: The Mackintosh Coat 9 In 1832, the first rubber factory was built, it was known as the Rosburg factory. Regrettably, when the rubber products made from the factory were left in the cold, it made them brittle, and when they were left in the sun the rubber melted, leaving customers to be discouraged.8 For many years, scientists have tried to develop new methods of increasing the strength of rubbers without being successful. However, in 1839, an American chemist named Charles Goodyear had accidently discovered a new way of making rubbers more durable. What he done was he accidentally dropped some mixture of natural rubber and sulphur on a hot stove, this has led to the vulcanization of the rubber. 8 In 1845, a Scottish inventor named Robert William Thompson invented the pneumatic tyre, this consisted of an inner belt made from natural rubber that was inflated with air, this was a major development to the motor industry because heavy steam engines could be able to travel on the roads without damaging the surface, this was further developed in 1869 where solid and hollow rubber were used to make the tyres. In the 1850s, rubber toys were being produced. 8 In 1876, an English explorer named Henry Wickham smuggled several seeds from the Hevea brasiliensis (which is the rubber tree found in Brazil) and took it to England. The English exported these seeds around the world, this has led to the increase in the supply of natural rubber around the world. 10 In 1883, an American chemist named George Oenslager developed a new method of accelerating the vulcanization of natural rubber with sulphur.7 He converted aniline into thiocarbanilide because it was easier to handle. From several experiments he conducted, he found out that thiocarbanilide was a good rubber accelerator for the vulcanization process. He was the first person to use carbon black as a filler for the rubber because it increased the strength of the rubber. 11 In 1909, a German scientist named Fritz Hofmann and his fellow scientists produced the first synthetic rubber known as methyl isoprene however the problem with this rubber is that it was expensive to make.12 In 1930, an American scientist named Wallace Carothers and his team produced a compound called chloropropene which then polymerised to form a solid which had a rubbery texture. The team had found out that the properties of this new polymer was similar to that of natural rubber. This polymer was named as Neoprene and was the first commercially successful synthetic rubber.13 Also in the 1930s, a German chemist named Walter bock had developed a new synthetic rubber which had better properties than that of natural rubber. He first tried to copolymerise dimethyl butadiene with isoprene and butadiene, this was successful as the new polymer had similar properties to the natural rubber. He then replaced dimethyl butadiene with styrene and copolymerised with butadiene, the polymer was named as SBR (styrene-butadiene rubber). This polymer was better than natural rubber because it did not wear out quicker than its counterpart, the polymer was later known as Buna-S for commercial purposes. 14 A better synthetic rubber was later developed by copolymerising acrylonitrile with butadiene, the polymer was known as NBR (Nitrile-butadiene rubber), it was the later known as Buna-N for commercial purposes. In 1940, an American inventor named Waldon Semon produced a new synthetic rubber known as Ameripol, this was made by copolymerising butadiene with methyl methacrylate. This synthetic rubber was cheap and easy to make, so it was a no-brainer that it was used in World War 2, and helped out rubber companies such as the Goodyear Tyre and Rubber Company during the war. After the war, the need for natural rubber died down, and the need for synthetic rubbers increased dramatically.15 In the 1960s, EPDM (which is known as Ethylene propylene Terpolymer Rubber) was produced. The rubber is made by copolymerising by a diene derivative, ethylene and propylene. The rubber has many advantageous properties over the synthetic rubbers, one of them is that they have good electrical insulating properties. EPDM rubber are now found in our everyday life such as hose, solar panels, electrical insulation etc.16 The use of synthetic rubber is on a steep rise, and many new rubber materials have been made duri ng the 21st Century. Natural Rubber How it is made? Natural rubber is produced by biosynthetic processes (in the form of latex which is a white liquid that is found when you cut the plant up) in many plants, but mainly from the Hevea Brasiliensis (The rubber tree coming from Brazil). There are two biosynthetic process to make latex. In the first stage, Acetyl-coenzyme A is converted to melavanic acid which then is then converted to iso-pentyl-pyrophosphate. The second process is the polymerisation induced by the first stage of the biosynthesis, from this process latex is created. The rubber form of the latex is then form by coagulating the latex particles. The rubber is made from a polymerisation of naturally occurring cis-polyisoprene. 17 Figure 3:Cis-polyisoprene, natural rubber 18 Properties of Raw Natural Rubber The rubber has a clear colour and hasnt got a well-defined shape and it is soft and sticky, however when the rubber is cooled down it crystalizes, so has a well-defined shape. The rubber has a low tensile strength meaning it tends to break if a low amount of tensile stress is put into it. It has a low abrasion resistance meaning the rubber will wear out quickly. It is soluble to organic solvents such as turpentine (which is an oiled that is attained by the distillation of resin from pine trees), ether, petrol, carbon tetrachloride, and naphtha (which is an oil attained by the distillation of coal tar). It is insoluble to hydrophilic solvents such as water, acetone, and alcohol. The rubber has a high elastic property, this means that when the rubber is stretched out it gets bigger, but when it is released the rubber goes back into its original shape. The rubber can only be elastic between 10 0C to 60 0C, this means under hot conditions the rubber would lose its elasticity. Another pro perty of the natural rubber is that it absorbs a large amount of water this means that it will be always wet and would need to dry it out before the next stage of the process. 19 Advantage of Raw Natural Rubber The hardness of the rubber can easily be adjusted, so can be able to shape or coat any form of objects this is because the rubber has a high elastic property, this means that when the rubber is stretched out it gets bigger, but when it is released the rubber goes back into its original shape. It can be used as an electrical conductor or an electrical insulator. Can be able to absorb vibration and noise. It is insoluble to hydrophilic solvents such as water, acetone, and alcohol. It also has a good surface friction so does not slide about easily. Disadvantage of Raw Natural Rubber The rubber can only be elastic between 10 0C to 60 0C, this means under hot conditions the rubber would lose its elasticity. The rubber has a low tensile strength meaning it tends to break if a low amount of tensile stress is put into it. It has a low abrasion resistance meaning the rubber will wear out quickly. It has a poor resistance to any organic compounds this is because It is soluble to organic solvents such as turpentine (which is an oiled that is attained by the distillation of resin from pine trees), ether, petrol, carbon tetrachloride, and naphtha (which is an oil attained by the distillation of coal tar). Another disadvantage of natural rubber is that it has a poor resistance to ozone meaning that when the ozone reacts with the double bonds it breaks, this causes a crack.20 The crack then grows steadily because of further ozone attacks so this causes the strength of the rubber to decrease massively and cause it to break. Another disadvantage of natural rubber is it has a poor UV resistance this also means that when it reacts with the double bond it breaks; this also means that cracks will from causing the tensile strength to be severely reduced meaning the strength of the rubber would be reduced massively and causing it to break. 20 Another disadvantage is that vulcanization of the rubber can occur spontaneously, so it is hard to control the raw state of the natural rubber. The vulcanization of Natural Rubber To improve the properties of the natural rubber, the process of vulcanisation is used to do this. Vulcanization is a process that involves adding natural rubber to a curing agent such as sulphur. The process is done under heat, so by heating the rubber in the presence of the curing agent the physical and chemical properties of the rubber would be significantly improved. The reason it does is, because when heating the rubber in the presence of the curing agent, the polymer chains are cross-linked by the agent, therefore the free-flowing macromolecules of the polymer chains becomes more rigid.21 Vulcanization must be under controlled condition to avoid creating a massive amount of cross-linking, this means that it will avoid making the rubber less elastic and more brittle. Figure 4: Cis-polyisoprene with sulphur cross-links after vulcanization 23 Properties of Vulcanised Rubber The rubber has a clear colour and it is hard and not sticky, when the rubber is cooled down it crystalizes, so has a well-defined shape. The rubber has a high tensile strength meaning it does not tend to break if a low amount of tensile stress is put into it. It has a high abrasion resistance meaning the rubber will not wear out quickly. It is not soluble to organic solvents such as turpentine (which is an oiled that is attained by the distillation of resin from pine trees), ether, petrol, carbon tetrachloride, and naphtha (which is an oil attained by the distillation of coal tar). It is insoluble to hydrophilic solvents such as water, acetone, and alcohol. The rubber has a high elastic property, this means that when the rubber is stretched out it gets bigger, but when it is released the rubber goes back into its original shape. The rubber can only be elastic between -40 0C to 100 0C which is better than what the given temperature range is for the natural rubber in its raw state, thi s means under hot conditions the rubber would not lose its elasticity. Another property of the natural rubber is that it does not absorb a large amount of water this means it can be dried easily before the next stage of the process. 23 Advantages of Vulcanised Rubber The hardness of the rubber can easily be adjusted, so can be able to shape or coat any form of objects this is because the rubber has a high elastic property, this means that when the rubber is stretched out it gets bigger, but when it is released the rubber goes back into its original shape. It can be used as an electrical conductor or an electrical insulator. Can be able to absorb vibration and noise. It is insoluble to hydrophilic solvents such as water, acetone, and alcohol. It is also insoluble to organic solvents such as turpentine (which is an oiled that is attained by the distillation of resin from pine trees), ether, petrol, carbon tetrachloride, and naphtha (which is an oil attained by the distillation of coal tar). It also has a good surface friction so does not slide about easily. The rubber has a high tensile strength meaning it does not tend to break if a low amount of tensile stress is put into it. It has a high abrasion resistance meaning the rubber will not wear out quickly. The rubber can only be elastic between -40 0C to 100 0C which is better than what the given temperature range is for the natural rubber in its raw state, this means under hot conditions the rubber would not lose its elasticity. Another advantage of the vulcanized rubber is that it does not absorb a large amount of water this means it can be dried easily before the next stage of the process. It has a better resistance to ozone and UV this means that less cracks form than in its raw state. This means that it is less likely to break than the raw natural rubber. Disadvantages of Vulcanised Rubber If the vulcanized rubber is burned it can be toxic for the workers and consumers this is because it contains sulphur cross-links which can form sulphur dioxide. Vulcanization must be under controlled condition to avoid creating a massive amount of cross-linking, this means that it will avoid making the rubber less elastic and more brittle. Another disadvantage of vulcanized rubber, is that when you heat the rubber it melts and then cools quickly, this is quite dangerous for the people who are handling it. Another disadvantage of using vulcanized rubber, is natural rubber are becoming more scarce, therefore the cost of making the vulcanized rubber is increasing. To overcome this problem, scientist have been trying to make vulcanized rubber out of synthetic rubbers such as styrene-butadiene rubbers (SBR), however the problem with this is that it is not cost effect and it is very expensive to make.24 Applications of Natural Rubber and Vulcanized Rubber The main usage of natural rubber is in the motor industry. It is used to make tyres and tubes in vehicles this is because it decreases any generation of heat in the tyres. It also offers high mechanical resistance. Tyres and tubes are used mainly in heavy duty vehicles such as trucks and tractors. 23 Natural rubbers can be used to make toys, footwear, balloons, glue and condoms. Another important application of natural rubbers is that they can be used to make latex gloves. Latex gloves are used in many industries such as the medical industry, chemical industry, and engineering industry, this is because due to the chemical and physical properties of the natural rubber mentioned above it can protect workers and consumers hands from hazardous chemicals.25 There are several applications for the vulcanized rubber. Vulcanized rubbers are much better to produce tyres than natural rubber this is due to having high abrasion resistance meaning tyres wont wear out quickly. The rubber is flexible, this means that it can be used to make hoses, tubes, coats etc Shock absorbers in vehicles are made from vulcanized rubbers due to being able to absorb vibrations easily.26 As the rubber, does not dissolve in water, it can be used to make waterproof clothing and footwears. Another application of using vulcanized rubber is that they can be used to produce cables for telephone housing, and can be able to produce insulations and conductors for electrical instruments. The reason why they are used in electrical instruments, is that have good electrical insulating and conducting properties. Synthetic Rubbers Synthetic Rubbers are made by copolymerising two different monomers under certain conditions. There are 3 conditions (the mixture can be in) it can be done in such as: emulsion, suspension and solution. There are 9 major classes of synthetic rubbers: Styrene-butadiene rubber (SBR), Poly(Butadiene-acrylonitrile) rubbers (NBR), Butyl Rubbers (IIR), Polychloroprene (CR), Ethylene-propylene rubbers (EPDM), Urethane rubbers (EU), Silicone rubbers (VMQ), Fluoroelestomer (FKM), Flurosilicone (FVMQ).27 In this 4 major classes are being discussed. Polychloroprene In 1930, an American scientist named Wallace Carothers and his team produced a compound called chloropropene which then polymerised to form a solid which had a rubbery texture. The team had found out that the properties of this new polymer was similar to that of natural rubber. This polymer was named as Neoprene and was the first commercially successful synthetic rubber.13 Neoprene is produced by the free-radical polymerisation of chloroprene. The chloroprene undergoes polymerisation under aqueous emulsion.28 Properties of Polychloroprene The rubber has a greyish green colour.28 The rubber has a high tensile strength meaning it does not tend to break if a low amount of tensile stress is put into it. It has a high abrasion resistance meaning the rubber will not wear out quickly. It can dissolve with organic solvents such as turpentine (which is an oiled that is attained by the distillation of resin from pine trees), ether, petrol, carbon tetrachloride, and naphtha (which is an oil attained by the distillation of coal tar). It is insoluble to hydrophilic solvents such as water, acetone, and alcohol. The rubber has a moderate elastic property, this means that when the rubber is stretched out it gets bigger, but when it is released the rubber goes back into its original shape. The rubber can only be elastic between -34 0C to 100 0C which is better than what the given temperature range is for the natural rubber, this means under hot conditions the rubber would not lose its elasticity. The rubber has a low flammability, and has a high resistance to weather and ozone.29 Figure 5: Polychloroprene 30 Advantages of Polychloroprene This rubber is tougher than natural rubber because it has a higher tensile strength than natural rubber meaning it does not tend to break if a low amount of tensile stress is put into it. It has a very high resistance to hot conditions and other weather conditions; this means that it does not melt or break easily. Another advantage of polychloroprene rubber is that they have a better resistance to ozone and UV this means that less cracks forms than in its natural counterpart. This means that it is less likely to break than the natural rubber. It has a low flammability and can be able to self-extinguish if it is on fire. The structure of the polychloroprene can be altered to create a new compound which can exhibit different chemical and physical properties. Disadvantages of Polychloroprene The rubber has a poor resistance to aromatic compounds such as benzene derivatives, they also have poor resistance to carbonyl compounds such as ketones and esters, and, also has a poor resistance to strong oxidising agents. Another disadvantage of polychloroprene, is that they are quite expensive to produce. 29 Typical applications of Polychloroprene Production of hoses Making belts Making cable covers for electrical instruments Styrene-butadiene Rubber In the 1930s, a German chemist named Walter bock had developed a new synthetic rubber which had better properties than that of natural rubber. He first tried to copolymerise dimethyl butadiene with isoprene and butadiene, this was successful as the new polymer had similar properties to the natural rubber. He then replaced dimethyl butadiene with styrene and copolymerised with butadiene, the polymer was named as SBR (styrene-butadiene rubber).14 Styrene-butadiene Rubber is produced by the free-radical polymerisation of styrene mixed with butadiene. The monomers undergo free- radical polymerisation under aqueous emulsion. The monomers can also undergo polymerisation in the form of solution.31 Properties of Styrene-butadiene Rubber The rubber has a brown -black colour. 31 The rubber has a high tensile strength meaning it does not tend to break if a low amount of tensile stress is put into it. It has a high abrasion resistance meaning the rubber will not wear out quickly. It can dissolve with organic solvents such as turpentine (which is an oiled that is attained by the distillation of resin from pine trees), ether, petrol, carbon tetrachloride, and naphtha (which is an oil attained by the distillation of coal tar). It is soluble to hydrophilic solvents such as water, acetone, and alcohol. The rubber has a moderate elastic property, this means that when the rubber is stretched out it gets bigger, but when it is released the rubber goes back into its original shape. The rubber can only be elastic between -45 0C to 100 0C which is better than what the given temperature range is for the Polychloroprene, this means under hot conditions the rubber would not lose its elasticity. 29 Figure 6: Styrene-butadiene rubber 32 Advantages of Styrene-butadiene Rubber This rubber is tougher than natural rubber because it has a higher tensile strength than natural rubber meaning it does not tend to break if a low amount of tensile stress is put into it. It has a high abrasion resistance meaning the rubber will not wear out quickly. Another advantage of styrene-butadiene rubber is that it is much more cost effective than natural rubber, and the production of the rubber is much more efficient than its natural counterpart. Disadvantages of Styrene-butadiene Rubber It has a poor resistance to any organic compounds this is because It is soluble to organic solvents such as turpentine (which is an oiled that is attained by the distillation of resin from pine trees), ether, petrol, carbon tetrachloride, and naphtha (which is an oil attained by the distillation of coal tar). Another disadvantage of natural rubber is that it has a poor resistance to ozone meaning that when the ozone reacts with the double bonds it breaks, this causes a crack. The crack then grows steadily because of further ozone attacks so this causes the strength of the rubber to decrease massively and cause it to break. Fillers like carbon black are needed to strengthen the rubber. Typical applications of Styrene-butadiene Rubber Production of car tyres Making mats Making shoe soles Poly(Butadiene-acrylonitrile) rubbers In 1931, scientists IG Farben developed a synthetic rubber which consisted of copolymerising acrylonitrile with butadiene, the polymer was known as NBR (Nitrile-butadiene rubber), it was the later known as Buna-N for commercial purposes. 14 Styrene-butadiene Rubber is produced by the free-radical polymerisation of styrene mixed with butadiene. The monomers undergo free- radical polymerisation under aqueous emulsion.14 Properties of Poly(Butadiene-acrylonitrile) rubbers The rubber has a yellowish colour.33 It has a high abrasion resistance meaning the rubber will not wear out quickly. It is insoluble with organic solvents such as turpentine (which is an oiled that is attained by the distillation of resin from pine trees), ether, petrol, carbon tetrachloride, and naphtha (which is an oil attained by the distillation of coal tar). It is insoluble to hydrophilic solvents such as water, acetone, and alcohol. The rubber has a good elastic property, this means that when the rubber is stretched out it gets bigger, but when it is released the rubber goes back into its original shape. The rubber can only be elastic between -34 0C to 121 0C which is better than what the given temperature range is for the Polychloroprene, this means under hot conditions the rubber would not lose its elasticity. However, at low temperature, the rubber loses its elasticity.29 Figure 7: Poly(Butadiene-acrylonitrile)34 Advantages of Poly(Butadiene-acrylonitrile) rubbers It has a very high resistance to hot conditions and other weather conditions; this means that it does not melt or break easily. Another advantage of Poly(Butadiene-acrylonitrile) rubber is that they have a better resistance to ozone and UV this means that less cracks forms than in its natural counterpart. This means that it is less likely to break than the natural rubber. It has a high abrasion resistance meaning the rubber will not wear out quickly. Another advantage of Poly(Butadiene-acrylonitrile) rubber is that it has a high resistance in oil this is because It is insoluble with organic solvents such as turpentine (which is an oiled that is attained by the distillation of resin from pine trees), ether, petrol, carbon tetrachloride, and naphtha (which is an oil attained by the distillation of coal tar). 29 Disadvantages of Poly(Butadiene-acrylonitrile) rubbers At low temperature, the rubber loses its elasticity. Another disadvantage of Poly(Butadiene-acrylonitrile) rubbers, is that they have poor resistance to carbonyl compounds such as ketones and esters, and, also has a poor resistance to strong oxidising agents. 29 Typical applications of Poly(Butadiene-acrylonitrile) rubbers Making nitrile gloves Can be used for O-rings Can be used to make hoses and tubing Ethylene propylene Terpolymer Rubber In the 1960s, EPDM (which is known as Ethylene propylene Terpolymer Rubber) was produced. The rubber is made by copolymerising by a diene derivative, ethylene and propylene. The rubber has many advantageous properties over the synthetic rubbers, one of them is that they have good electrical insulating properties. EPDM rubber are now found in our everyday life such as hose, solar panels, electrical insulation etc. 16 Ethylene propylene Terpolymer Rubber is produced by the copolymerisation of ethylene, propylene and a diene derivative. The monomers under copolymerisation in the form of solution. Figure 8: EPDM 35 Properties of Ethylene propylene Terpolymer Rubber The rubber has a yellowish colour. It has a high abrasion resistance meaning the rubber will not wear out quickly. It is insoluble with organic solvents such as turpentine (which is an oiled that is attained by the distillation of resin from pine trees), ether, petrol, carbon tetrachloride, and naphtha (which is an oil attained by the distillation of coal tar). It is insoluble to hydrophilic solvents such as water, acetone, and alcohol. The rubber has a good elastic property, this means that when the rubber is stretched out it gets bigger, but when it is released the rubber goes back into its original shape. The rubber can only be elastic between -40 0C to 149 0C which is better than what the given temperature range is for the Poly(Butadiene-acrylonitrile) rubber, this means under hot conditions the rubber would not lose its elasticity. 29 Advantages of Ethylene propylene Terpolymer Rubber It has a very high resistance to hot conditions and other weather conditions; this means that it does not melt or break easily so does not age very easily. Another advantage of Ethylene propylene Terpolymer rubber is that they have a better resistance to ozone and UV this means that less cracks forms than in its natural counterpart. This means that it is less likely to break than the natural rubber. It has a high abrasion resistance meaning the rubber will not wear out quickly. The rubber is very cost effective, so it is cheaper to make than the other rubber compounds. 29 Disadvantages of Ethylene propylene Terpolymer Rubber It has a poor resistance to oils, this is because It is insoluble with organic solvents such as turpentine (which is an oiled that is attained by the distillation of resin from pine trees), ether, petrol, carbon tetrachloride, and naphtha (which is an oil attained by the distillation of coal tar).29 Typical applications

Economic Impact of the Added Worker Effect :: essays papers

Economic Impact of the Added Worker Effect 1. Income Effect: the income effect is the response of desired hours of leisure to changes in one’s income. If wages are held constant and income increases then the desired hours of work will decrease. The relevance of the income effect in regards to the study of labor economics is very important. Employers, economists and Government institutions have the ability to determine the amount of time workers’ will seek to either choose more hours of work or more hours of leisure. This can be used to estimate the average number of work and leisure hours a sample of workers will utilize in a year or during a trend. 2. Added Worker Effect: The added worker effect occurs when there is a family that has only one bread winner that loses his or her job. Because of the lost income the family may choose for the recently unemployed family member to stay home while the other family member seeks employment. This then produces a new worker in the work force which is the added worker effect because the person was not already in the work force or seeking employment. The added worker effect is crucial to economists and the Government to determine the unemployment rate during times of recession as well as the rate of new entries into the work force. 3. Compensating Wage Differentials: Compensating wage differentials determines the level of risk an employee and employer chooses to offer. If an employer has an unsafe work place then their cost of reducing risk is relatively low compared to an employer who already has a safe work environment. At the same point, a worker chooses the level of risk he/she will assume in relation to the offered rate of pay. This is very important in the study of labor economics as it shows how workers and employers are affected when the state and Federal government pass job safety laws that demand higher levels of safety measures implemented in the workforce. Short Problems 1. 2. a) Limnologist 472000 = 449523.81-15000 = 434523.81 1.05 Chef 500000 = 476190.48- 40000 = 436190.

The Short And Happy Life Of Francis Macomber :: essays research papers

In the short story The Short and Happy Life of Francis Macomber, there are three main characters, Mr. Wilson, Mr. Francis Macomber, and Mrs. Margaret Macomber, who are on an African Safari together. There are also three animals repeatedly mentioned throughout the story, which each represents a main character. The animals are a lion, a buffalo, and an impala.   Ã‚  Ã‚  Ã‚  Ã‚  Mr. Macomber, who is â€Å"very tall, very well built† and â€Å"considered handsome,† is on a safari with his wife. While on the safari he goes and hunts a lion. After wounding it with his gun, he becomes too afraid to go and finish the lion off, so he runs like a little baby. Mr. Macomber is later known as a coward so he best relates to the impala in the story. The impala is a beautiful animal and very skinny and sleek. When the impala were shot at, they ran super fast and when Mr. Wilson feels the fear of the lion he runs just as fast. Also when his wife shoots him in the head towards the end of the story, the bullet goes right to his head. When Mr. Macomber shoots the impala the bullet goes right to its head and the impala dies immediately just as he did.   Ã‚  Ã‚  Ã‚  Ã‚  Mrs. Macomber, who is Mr. Macomber’s wife, started out in the story seeming like a normal lady. Later on it was obvious she did not care for her husband and was extremely rude to him. She should be related to the buffalo in this story, because she is very strong. She is running away from Macomber but at the same time she is chasing him and wants him dead. She is hard to get rid of and won’t give up until she has the last word.   Ã‚  Ã‚  Ã‚  Ã‚  Mr. Wilson, who is the Safari guide, best relates to the lion in this story because he is very brave. He is very respected and not afraid of any of the other animals. The way the story describes the â€Å"majestic† animal is how Wilson is described to be by Margaret.

Essay --

Hydraulic fracturing, or â€Å"fracking† is a process in which natural gas and oil are extracted from shale rock layers deep within the earth by creating fractures below the earth’s surface. This is done by injecting a mixture of water, sand and chemicals at high pressure into wells. There are a number of environmental concerns related to hydraulic fracturing. One concern is the amount of water it takes to extract these resources – it could involve up to 5.9 billions gallons of water per day. In order for these fracking sites to get all that water 200 trucks are needed in order for this to happen. In drought prone areas of the country, this could create additional strain on the environment. The areas that are most prone to drought are areas like Texas, Florida, Georgia, Louisiana, Virginia, and Kentucky along with other states surrounding them. Droughts take place all over the United States but most severely in the south as shown in this map. The dark, dark red are the states that have the most number of drought evens occur per year. The chemicals that are involved in the process are al...