UV-vis works Essay Example for Free

UV-vis works Essay Even though I accidentally spilled most of my product while pouring it into the separatory funnel, the product left was identical to everyone elses by comparison of the UV-vis spectrum.  Discussion  One possible source of error in this experiment occurred when I spilled the product. Although a small amount of it remained in the beaker, I decided to pipet the  spilled product off the desk to save as much as I could in order to complete the experiment. At first I thought this might cause my product to be somewhat impure, but after looking at the UV-vis spectra, it was obvious this had no effect on the outcome. My spectrum looked perfectly fine. Conclusion UV-vis can be very helpful in finding out how pure your product is and what the components are by looking where the absorption bands are and the extent to which the components were absorbed. UV-vis works by electrons moving from the ground state to a higher excited state. The types of transitions possible are. The sigma to sigma star transitions take place at 200-700 nm and are usually not seen in UV-vis spectrum. N to sigma star transitions require less energy than sigma to sigma star transitions and occur at 150-250 nm. The last type of transitions occur between 200 and 700 nm and are the type which occur in the Cu(TTP) spectrum. Peaks that are shifted to shorter wavelengths caused by transitions are named blue shifts. The peaks that are shown in our Cu(TTP) spectrum are caused by transitions and are classified as red shifts. This is caused by attractive polarisation forces between the solvent and the absorber, which lower the energy levels of both the excited and unexcited states. This effect is greater for the excited state, and so the energy difference between the excited and unexcited states is slightly reduced resulting in a small red shift. This effect also influences   transitions but is overshadowed by the blue shift resulting from solvation of lone pairs (UV-vis Absorption http://www.shu.ac.uk/schools/sci/chem/tutorials/molspec/uvvisab1.htm) Questions and Answers 1. Why does Cu(TTP) elute before H2TTP? The copper would elute first. The reason for this is because of the acidity of the hydrogen atoms. Since the hydrogens are acidic, they want to hold onto the silica gel, which will cause them to elute after a longer time period.  2. The rates at which compounds elute from a silica gel column depend on any pretreatment of the silica gel. In which case would a compound elute faster: down a column made of silica gel that had been previously heated at 150 degrees Celsius under vacuum for 8 hours, or down a column made of silica gel that had been sitting open in the laboratory for a few days? Explain. When you heat silica gel, water evaporates off the gel leaving open sites where polar molecules can bond. When you let silica gel out in the open, it will collect water molecules on it. Compounds would elute faster down a column that has been heated at 150 degrees for 8 hours because the gel would be dry.  3. A mixture of cis and trans isomers of the neutral complex Cr(CO)4[P(C6H5]2 is loaded onto a silica gel and eluted with CHCl3. Which isomer would elute first, and why? The trans isomer would elute first. References Skoog Douglas; Holler F. James; Nieman Timothy A., Principles of Instrumental Analysis, fifth edition, Thompson Learning: 1998.  Quinn 6  UV-Vis Absorption Spectroscopy-Theory. http://www.shu.ac.uk/schools/sci/chem/tutorials/molspec/uvvisab1.htm.

Benefits of the Great Wall of China

Benefits of the Great Wall of China The Great Wall The text The Great Wall, by John Man, is about the worlds longest man made structure. Ranging from eastern to western China the length of the great wall remains unknown because the wall does not form a single continues line. There are several gaps and its been destroyed and rebuilt during different dynasties. Measurements vary between 2,694 and 6,000 kilometers from the western desert to the sea (Man, 5). The section that was built in the Ming Dynasty is about 25 feet tall and 16 feet wide. In Chinese, the symbol for wall is ambiguous; it can mean both Long City, and Long Walls. Construction of the Great Wall began around 214 BC and it was maintained until the 16th century. The Wall that was built in the Qin Dynasty is the most famous one because it was the first and oldest section that still remains today. The latest or the most current segment was built in the Ming Dynasty. There is much more to it than just a barrier; the wall itself contains fortresses, barracks, guard towers and beacon towers (Man, 5). Though the Great Wall is a national symbol of identity for the Chinese, the reason for its construction is commonly unknown. Most people believe that the wall was built to create protection from the barbarous nomads in northern China who were attacking them, but this was not the case. John Man in The Great Wall argues that the nomad attacks were a justification for the destruction of the tribes. The nomads were not the ones to initiate violence; it was the Chinese that provoked and attacked the nomads for land. The Wall was never the barrier it seemed or was claimed to be because nomads could still easily go over or through it while the Chinese empire ruled and influenced both side of the wall (Man, 8). So it was useless against the Mongols in the north. It was Chinese expansionism that eventually forced the evolution of pastoral nomadism and Chinese expansionism that created the threat (Man, 21). The construction of the wall served mutliple purposes. One, it defined spheres of interest, marking a frontier and confining the unruly nomad populations where they could eventually be turned into workers (Man, 8). Two, it was a way for ambitious leaders to flaunt their power and warn alien threats. The wall was first created when China was divided into three different states: the Zhou in the northern borderlands, the Qin in south and west, and the Yen in north and east. These rulers each built walls for protection from each other and to show that they were serious about ruling (Man, 23). In 221 B.C. Qin Huang conquered and unified all the states and symbolically demolished the inter-state walls. He then extended the remaining wall into the northern frontier for protection from an Xiongnu invasion (Great Wall). The wall eventually became Chinas main civic project, comparable in scope to the pyramids in Egypt, and construction continued until the last dynasty in the 16th century. One of the biggest advantages of the Great Wall was that it created a sense of identity for the Chinese. It portrayed their endurance and their economical and political power. Although it was functionally useless and took hundreds of years to complete, it worked as a symbol of authority and power in the eyes of Chinas opponents and enemies. It also isolated the nomadic tribes that lived in the northern side of the wall, forcing them to participate in barter and trade. One of the advantages of the great wall was this forced increase in commercial and trade. Scholar Jia Yi states, our markets beneath the Great Wall will surely swarm with the Xiongnuà ¢Ã¢â€š ¬Ã‚ ¦When the Xiognu have developed craving for our rice, stew, barbecues and wine, this will have become their fatal weakness. Border Markets Thrived(60). The Wall also helped protect traders and administrators, which encouraged a merchant middle class in the western kingdoms, leading China to be richer than ever. While the empire was split in three different states, it was the nobles who were responsible for organizing a workforce for the construction of the walls. Peasants were forced to work on the wall by their nobles (Man, 23). People suffered from the forced labor it took to build the Great Wall, (Man, 123). It was estimated that during the construction of the wall, from 5th to 16th century, about 2-3 millions Chinese workers lost their lives (Great Wall). They didnt have a formal burial, the workers that died were sealed inside the wall as if they were born to support in weight both in life and in death. The workforce was divided into three different groups: soldiers, criminals, and ordinary people. Millions were called to work on the Wall, leaving their families and loved ones behind; even children had to join the workforce (Labor Force of Great Wall). The wall led to a large numbers of deaths and injuries during the years of its construction. It split up families and widowed many women. Not only did the wall have a negative effect on the citizens of the empire but it also had a negative impact on the nomads that lived on the northern side of the wall. It restricted their area of stay and the resources they had, limiting their amount of space for animals and restricting their travel to alternative trade or lands. This eventually led nomads to unify under the Mongolian Empire. The Mongolian Empire was led by emperor Genghis Khan, who organized raids and attacks on the Chinese Empire. The wall might have been a great authoritative representation, but it had an equally strong negative effect on the communities surrounding it. The wall that was built by the first emperor Qin was not sustainable; it was made of earth rather than stones, causing the wall to vanish over the years. Later dynasties would then rebuild it using earth, wood, or stones. Originally, the earth wall was made from was a mix of mud and local grass straws. The wall in north of Guyuan and in Yinchuan is the oldest original earth section. Later, lacking any efficient form of transportation for the materials, the workers would just adapt local resources. They would use rocks from nearby mountains or rammed earth from the plains. It wasnt until the later dynasties started expanding the walls to Hohhot and Beijing that carved stone began to be formally and universally used. Because of this patchwork of materials, some parts of the wall were made of chunks of flat, slate-like rock and ran along a hillside while others used bricks (Man, 8). During the Ming dynasties the walls were constructed using tiles, lime, and stone, which managed to last longer and be more effective (The Wall). Because the bricks were easier to carry compared to stones and earth, they made it easier for the workers to build the walls (The Wall). The stones were still used for the foundations since they could hold the walls weight better under different conditions. As years passed, people continued to acquire better resources and methods to construct the walls. The time and the location of the structure help determine the reasons behind the creation of the walls. It was built at a time where competition and power among the different states and regions was at its peak, different Emperors wanted to intimidate their respective enemies by showing them that they had the economic and political power necessary for this huge civic project. It was more of a symbol of their power rather than functionally protective as there was no real exterior threat to the dynasties. Even if there was, the nomads had no problem climbing or going through the wall. To them, the wall was not an obstacle. The Great Wall was built at a time where emperors wanted to flaunt their dominance to intimidate any potential enemy attacks. The great wall was am intimidating structure, a series of safe-houses for traders, a hugely extended barracks, a road for the transport of goods-and thus, as the second meaning of the symbol for great wall in Chinese implies, a very long city. Today the great wall is a representation of peace. A Tibetan said The Great Wall is a masterpiece containing the wisdom and diligence of all the peoples and nationalities of China. As the years passed, the wall became more redundant. Today the wall is a representation and symbol of China. The wall is no longer a barrier or a border but a pure symbol of a Chinese heritage. It attracts millions of people from all over the world who come to see the worlds largest structure. Useful in its time, today construction of the wall would create a dispute among United Nations. It would be even less functionally protective as a wall would not stop the intentions of any outside threat with the technology and weapons we have today. The Great Wall by John Man isnt the best literature Ive read, especially for this assignment. The most useful information I received for this assignment was in the introduction. The rest of the book focused more on the broader history of China and its dynasties. Even though it was interesting to learn about the different dynasties, it wasnt really related to our assignment and wasnt engagingly written. I felt like there was too much factual information for a reader to keep focused on the main idea. The author didnt have clear specific information about the wall. It was scattered all over different chapters without a clear organizing structure. It wouldve been better if he included more information on and of the people who built the walls, their lifestyle, and the conditions in which they worked in. He could have also included more information on the lifestyles of nomads and how the wall changed their traditional cultures.

Thrust Vectoring :: War Technology Technological Essays

Thrust Vectoring Imagine two US Air Force Jets with controls not responding, they are heading right for each other, the pilots don’t have enough time to eject, there’s a mid-air explosion, and the needless death of American servicemen. About one fifth of peacetime fighter losses during the past few years were due to loss of control. Now imagine that the US has been developing the technology to prevent this for the last decade, but due to budget problems this technology was never installed on our fighters. I’m talking about a Thrust Vectoring. This engineering term describes the use of an engines nozzle to direct the force coming from a jet engine in different directions other then straight out the back. Besides tragic, needless deaths, this technology has a military significance for front line fighter jets. With the wars in Iraq and Afghanistan, Americans have seen the devastating power of our Air Force on Countries without a serious Air Defense network, like Is rael or Great Britain. These are countries with not just a Surface to Air Missile (SAM) threat, but an Air Force that can rival ours in its current state. Thrust Vectoring is the technology that will make our fighter jets true rulers of the air, not just on bombing runs, but air-to-air combat, better know as â€Å"Dog Fighting†. Thrust Vectoring was first used in a trivial form on Nazi Germany’s V-2 rockets. These rockets were devastating to the Allies in WWII with their accuracy due to graphite control vanes that helped the guidance of the missile. Modern rockets, both SAMs and Air-to-Air missiles have been using thrust vectoring to increase their agility in flight, and hence make them more lethal. During the Cold War German military planers recognized the shear numbers of Soviet fighters, and believing that any war would include intense Dog Fighting, began to look for ways to even the odds. Wolfgang Herbst with the Messerschmitt-Boelkow-Blohm, now Deutsche Aerospace, Company led a team in Post-Stall engineering. Post-Stall describes a flight condition in which normal flight controls, like flaps, are no longer sufficient to maintain the flight ability of the aircraft. His team investigated new flight laws to describe the movement of an aircraft in Post-Stall flying conditions.

Heart Of Darkness Response Assignment :: essays research papers

â€Å"They were dying slowly-it was clear. They were not enemies, they were not criminals, they were nothing earthly now, nothing but black shadows of disease and starvation, lying confused in the greenish gloom†. (page 14 para. 3, line 1). The quote is coming from Marlow, upon arriving at the outer station, and first witnessing the devastation the Belgians have caused the native peoples. He is speaking about the black men, who have been enslaved, dying all around him. He can see the work they are being made to do, and finds it a great horror, similar, perhaps, to what hell must be like. This quote also shows Marlow’s first recognition to an epiphany, he will later realize, as imperialism. He says clearly, these men can not be viewed as criminals, for the only function they seemed to be carrying out was dying, and die they did, in great numbers, and at the hands of the â€Å"enlightened† Europeans. I believe his conscience was getting the better of him, first seeing the death, disease, starvation, and chaos all around, allusions of a modern day genocide, which righteous people can not stand to watch, but are helpless to do anything about it. Descriptions of Africans dying, or more precisely, being killed, are common stories surrounding imperialism. Heart of Darkness, finely details the worst kind of African imperialism, the Belgian kind. Millions of people, in what today is called the Congo, were forcefully enslaved, and then made to gather ivory tusks, and rubber plants, all the time being treated as animals, for the sole purpose of lining the pockets of the Belgian monarchy. These scenes shock the more caring, and kind hearted reader, in today’s world, and leave questions swirling in the mind about how atrocities, similar to the ones described in Heart of Darkness, could have been carried out, by a supposed more enlightened society. Surprisingly enough, European imperialists do not hold the sole rights to death and destruction. In fact, simply by reading a history book of the last 2000 years, the reader may come to the conclusion that imperialism was a natural part of empire expansion. Just look at the Egyptians , the Assyrians, the Greeks, the Romans, the Huns, the Moslems, the Christians, and finally the British. What did they all have in common, first they all conquered territory, and usually to do this they needed to kill indigenous people, so that they could use newly conquered land, for their needs.

The Americanization of Canada Essay -- American Culture Canadian Cultu

â€Å"Former Canadian Prime Minister Pierre Trudeau once compared liking next to the United States to sleeping with an elephant. He said, ‘You cannot help but be aware of its every movement.’†   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  http://www.pbs.org/pioneerliving/segments/Americanization.htm The issue of American culture and its globalization has raised a lot of controversy. â€Å"The era of globalization† is becoming the preferred term to describe the current times. The term Americanization has been around for years. It was first used when the United States was being heavily immigrated into. The new Americans began to enjoy the freedoms associate with our country and gradually began to act less like a foreigner and more like a real American. Today we are able to witness an essence of American culture almost everywhere around the world by what we call cultural icons of our times. Sneakers, blue jeans, burgers, Hollywood blockbusters are only a few. To many, globalization is synonymous with Nike, Levi's and MTV. In fact, the most visible sign of globalization seems to be the spread of American burgers and cola to nearly every country on earth. It crowns the United States the king of pop culture. Globalization does more than allow businesses to operate in countries all around the globe. In addition to global commerce, globalization allows for social activism, journalists, academics, and many others to work on a global stage. According to Keith Porter, a co-host and executive producer of a nationally syndicated radio program on world affairs globalization can be both a good and bad thing. He quotes, Thomas Friedman in saying â€Å"Globalization can be incredibly empowering and incredibly coercive. It can democratize opportunity and democratize panic. It makes the whales bigger and the minnows stronger. It leaves you behind faster and faster, and it catches up to you faster and faster. While it is homogenizing cultures, it is also enabling people to share their unique individuality farther and wider." Without the role of globalization it is not possible to speak of a term called American dominant culture. The dramatic effect of globalization has and will be strengthening this term. People around the world have become less like themselves and more like each other. The most common name that puts this in front of our eyes is McDonald’s. When a McDonald’s restaurant opens in a f... ...ogies that have made transcontinental communications possible has ensured that the world slightly conform and make very different cultures mesh into various ones that more resemble each other. As communication techonolgy continues to become better and more powerful it will be interesting to see the changes that it will lead to. Perhaps in ten years college students will no longer be writing about the topics of globalization and Americanization. Instead they will write about the time when cultures were so very different from each other. Works Cited Cantor, Paul A. Gilligan Unbound: Pop Culture in the Age of Globalization, Rowman and Littlefield Thussu, Daya Kishan. "International Communication: Continuity and Change" Hodder Arnold Publishing Sources Cited http://www.pbs.org/pioneerliving/segments/Americanization.htm http://www.encyclopedia.com/searchpool.asp?target=@DOCTITLE%20Americanization http://globalization.about.com/gi/dynamic/offsite.htm? http://www.usemb.nl/051800.htm http://www.infocan.gc.ca/facts/index_e.html http://www.tv.cbc.ca/national/pgminfo/border/filmfact.html http://www.rice.edu/projects/topics/globalization/movies-germany.htm

New Manager Stumbles Case Analysis Essay

Suggest some options for Goldstone at this point. What might he do to help himself achieve success in his current situation?  First, Goldstone must think back about what he has done in the last 6 months and analyze his own performance. In this way, he can find out what mistake he has made in his management ; also, he needs to figure out the reasons for why he was making mistakes. Afterwards, he needs to face the reality and encourage himself to ask people who is on higher level when he does not know what to do. For example, in this situation, he needs to stop being defensive and reluctant of talking with Ludlow. Instead, he needs to use his valuable experience to help him propose a solid plan and discuss with Ludlow. The conversation between him and Ludlow was not helpful for both his and the company’s development. Therefore, they need to both realize the problem and start to cooperate with each other in order to create a double-win situation for them. Secondly, it will be an great asset for Goldstone if he can find a mentor within the company or the company could assign a mentor who had sufficient experience to help Goldstone out. Indeed, the company had many training programs and also the employee development training seminar which allowed the managers to sit together and exchange their thoughts and experience. However, the training program was all about theory and was really difficult for managers to put it into action; also, the training seminar were not effective as all the managers were just feeling sympathized but not sharing any useful management advice with each other. In order to find out an effective way to solve the current problems, he needs to talk with a mentor whom he can consult from. Moreover, company needs to let him know that the mentor is more than welcome to consult him and answer his questions. Through this way, Goldstone can articulate the company’s strategy and benefit for a long term. Furthermore, Goldstone can suggest the executive level to develop more practical training and management skills for the new managers. In this way, Goldstone can have a better relationship with  executive level people as they can see Goldstone are putting efforts to this company; also, it is good for Bulwark’s long term development. Last, Goldstone needs to work on his people management. In addition to consulting from his potential mentors and Ludlow, he needs to figure out a way to manage the sales rep working for him. Instead of simply managing and instructing them what to do, he needs to maintain a good relationship with them. In other words, he needs to get respect from them and get trust from them. He needs to apply golden rule and think for his sales rep which can help him avoid accidents like losing Puckett happen again. Also, he needs to use his courage and his strength to win the respect from his best sales rep Tony Skrow. As Skrow is the most successful sales rep in his team, winning the respect and trust from him can help Goldstone getting the entire control of the whole team.

Blood Supply to the Muscles

The Physiology of Fitness Assignment 1 Helpsheet Step 1 You need to introduce your assignment, here I would define two key terms for the entire of this assignment these are chronic and acute. Example Answer There are many changes to the body during exercise; these can be classified as acute and chronic. Acute meaning they are short term and happen almost instantly with the onset of exercise. The other chronic is long term and allows the body to adapt its capabilities so therefore it can meet new demands in the future.Examples of these will be discussed in time through each one of these bodily systems: musculoskeletal, energy, respiratory and cardiovascular system. Step 2 At this stage of the assignment you need to look at the first body system of musculoskeletal. Here you need to identify all of the acute changes that take place within this system and then relate this to a sporting example. Some of the changes you need to discuss are: Increased blood supply, increase in muscle pliabi lity, increased range of movement and muscle fibre micro tears.Example Answer Increases the range of movement – when we start to exercise the movements of our joints means that synovial fluid starts to secrete within the joints. The fluid becomes less viscous and therefore the range of movement within the joint increases. An example of this in sport is the need for a warm up for a butterfly swimmer. So they can get the full range of movement at the shoulder joint that area has to be warmed up prior to the race. Step 3Keeping the musculoskeletal changes in mind you now need to discuss the chronic responses, these are: hypertrophy, increase in tendon strength, increase in myoglobin stores, increase in muscle strength, increase in tolerance to lactic acid, increase in bone calcium stores, increased stretch of ligaments, increased thickness of hyaline cartilage and increased production of synovial fluid. Example Answer Increased production of synovial fluid – as mentioned previously the movements stimulate the secretion of synovial fluid.With regular exercise this fluid on initial release is less viscous and the range of movement at the joint increases as connective tissue improves its flexibility. An example in sport is a high jumper. Over a prolonged period of training their knee joint in particular will take a lot of strain, this repetitive strain will allow for the knee joint to increase synovial fluid production as the jump can not e performed without the knee joint. Step 4 You now need a new side heading of energy systems and at this stage we will talk about the acute responses of the energy system.You need to discuss each of the three energy systems and how they initially respond to exercise. Example Answer Creatine Phosphate System – When exercise intensity is high, or energy needs are immediate, Creatine phosphate stored in the muscle is broken down to provide energy to make ATP. When the high energy bond in Phosphocreatine is broken, the energy it releases is used to resynthesise ATP. Explosive work can be achieved but for only short periods at maximum intensity.An example of this would be triple jump, if the athlete needs immediate energy this system is used, as the sport will last up to 10 seconds on completion of each jump it can not wait for energy from the Lactic Acid system. Step 5 In this section you need to discuss the chronic changes which apply to the energy system, you need to discuss in particular the aerobic system but also make specific reference to an increase in aerobic and anaerobic enzymes and increased use of fats as an energy source. Example AnswerIncreased use of fats as an energy source – Fat oxidation increases if exercise extends to long periods, as glycogen levels deplete. This is particularly prevalent to marathon runners. These athletes will burn of the glycogen in the carbohydrates digested and will need another source of energy to refer to this is where fats are then used. St ep 6 Under the side heading of respiratory you need to discuss the acute changes in this system. You will need to mention the following changes: increased breathing rate and increased tidal volume as well as many others.Example Answer Increased breathing rate – due to the fact the working muscles require energy during exercise the brain sends signals to increase the breathing rate. This increase in breathing rate allows for more oxygen to be taken in and then delivered to the working muscles. It also allows for the waste products to be exhaled much quicker. An example of this is a footballer will gradually increase their breathing rate the longer the game lasts and the more that the muscles demand oxygen to fulfil physical movements. Step 7You now need to discuss the chronic changes to the respiratory system again relating them to sport to show understanding; you need to include the following: increased vital capacity, increase in minute ventilation, increased strength of res piratory muscles and increase in oxygen diffusion rate. Example Answer Increased strength of respiratory muscles – like any muscle the more that it is worked the greater it’s strength, therefore the same can be said of the intercostals muscles of the chest cavity, due to the increased work load in breathing they become more efficient allow for greater expansion of the chest.An example of this would be a tour de France cyclist. Due to the intense nature of the event there chest capacity will have to increase to meet the constant demands. Step 8 Under the side heading of cardiovascular system you will now need to discuss the acute changes to this system giving sporting examples. The following changes will need to be discussed: Heart rate anticipatory response, activity response, increased blood pressure, vasodilation and vasoconstriction. Example AnswerVasoconstriction – this is where the blood vessels decrease in diameter to restrict the flow of blood to an area of the body which does not need the blood supplies as much as another area. An example of this is a boxer, here due to the repetitive punching from the fighter the arms and upper body needs the blood to allow for regular movement, the legs receive less. This is why when a fighter is knocked down commentators sometimes say â€Å"his legs have gone† this is because of a lack of oxygen as it has all gone to the upper body and brain. Step 9 Finally you need to talk about the chronic change to the cardiovascular system.This area is vast and needs a lot of detail. The changes you will need to discuss include: cardiac hypertrophy, increase in stroke volume, cardiac output, resting heart rate, capillarisation, blood volume, blood pressure, recovery time and aerobic fitness. Example Answer Decreased resting heart rate – this is a chronic change because the heart adapts and learns how to cope with the demands of extreme and intense workouts the more you exercise, this therefore means the normal everyday task do not apply as much strain to the body therefore not requiring the heart to increase blood supply to the areas of the body that are working.