Mikume

TITANIUM EXTRACTION ASSIGNMENT 1 1. TiO2+Cl2—————–TiCl4+O2 2. Why is an atmosphere of argon used for this reaction ? The titanium (iv) chloride is added to a reactor in which very pure sodium has been heated to about 5500c -everything being under an innert argon atmosphere. During this reaction the temperature increases to about 10000 c . The reaction is carried out in an argon atmosphere to prevent magnessium and sodium from reacting with oxygen in the air. 3. Another gas used instead of argon. ny of the elements in group O of the periodic table including helium ,neon,krypton,xenon,and radon which are monoatomic and with limited excemptions chemically innert. 4. Why titanium is an expensive metal Titanium is very expensive because it is akward to extract from ore -for example rutile,TiO2 . You cannot use carbon reduction Titanium can not be extracted by reducing the ore using carbon as a cheap reducing agent. The problem is that titanium for ms a carbide TiC,if it is heated with carbon,so you dont get the pure metal that you need. The presence of the carbide makes the metal very brittle.That means that you have to use an alternative reducing agent. In the case of titanium,the reducing agent is either sodium or magnessium. Both of these would ofcoarse first have to be extracted from their ores by expensive processes. 5. The atom economy of the process used to extract titanium. Total mass of reactants =212g Total mass of desired product=22g Atom economy=mass of desired product *100% total mass of reactants 22*100 =10. 774 212 The total economy of the Kroll process is 10. 3774 . 6. The atom economy will be lower since it was carried out in an ideal situationwhere all factors are constant and there is no external interference but in real situation extal forces like heat loss,temparature,impurities will affect the system hence a lower value Mikume TITANIUM EXTRACTION ASSIGNMENT 1 1. TiO2+Cl2—————–TiCl4+O2 2. Why is an atmosphere of argon used for this reaction ? The titanium (iv) chloride is added to a reactor in which very pure sodium has been heated to about 5500c -everything being under an innert argon atmosphere. During this reaction the temperature increases to about 10000 c . The reaction is carried out in an argon atmosphere to prevent magnessium and sodium from reacting with oxygen in the air. 3. Another gas used instead of argon. ny of the elements in group O of the periodic table including helium ,neon,krypton,xenon,and radon which are monoatomic and with limited excemptions chemically innert. 4. Why titanium is an expensive metal Titanium is very expensive because it is akward to extract from ore -for example rutile,TiO2 . You cannot use carbon reduction Titanium can not be extracted by reducing the ore using carbon as a cheap reducing agent. The problem is that titanium for ms a carbide TiC,if it is heated with carbon,so you dont get the pure metal that you need. The presence of the carbide makes the metal very brittle.That means that you have to use an alternative reducing agent. In the case of titanium,the reducing agent is either sodium or magnessium. Both of these would ofcoarse first have to be extracted from their ores by expensive processes. 5. The atom economy of the process used to extract titanium. Total mass of reactants =212g Total mass of desired product=22g Atom economy=mass of desired product *100% total mass of reactants 22*100 =10. 774 212 The total economy of the Kroll process is 10. 3774 . 6. The atom economy will be lower since it was carried out in an ideal situationwhere all factors are constant and there is no external interference but in real situation extal forces like heat loss,temparature,impurities will affect the system hence a lower value

Role of Youth in Eradicating Corruption

Laser and its medical applications Presented by S. vignesh J. sabastian The Advent of the â€Å"Laser Scalpel† Early experimenters with medical lasers pointed out that there are surgical operations that are difficult to perform with the conventional scalpel and that a laser beam might be used instead. Initial trials showed that a finely focused beam from a carbon dioxide gas laser could cut through human tissue easily and neatly. The surgeon could direct the beam from any angle by using a mirror mounted on a movable metal arm. Several advantages of laser surgery quickly became apparent.First, the light beam is consistent, which means that it gives off the same amount of energy from In this photo taken during open-heart surgery, a doctor uses a laser probe to punch small holes in the patient's heart muscle to increase the organ's blood flow. one second to the next. So as long as the beam is moving along, the cut it makes (the incision) does not vary in depth; whereas when using a scalpel a doctor can accidentally make part of the incision too deep. A second advantage of the surgical laser is that the hot beam cauterizes, or seals off, the open blood vessels as it moves along. This works well mainly for small vessels, such as those in the skin. The doctor still has to seal off the larger blood vessels using conventional methods. ) Still another advantage is that the cells in human tissue do not conduct heat very well, so the skin or any other tissue near the laser incision does not get very hot and is not affected by the beam. This advantage of laser surgery is very helpful when a doctor must operate on a tiny area that is surrounded by healthy tissue or organs. It should be pointed out that the â€Å"laser scalpel† is not necessarily the best tool to use in every operation.Some doctors feel that while the laser is useful in some situations, it will never totally replace the scalpel. Others are more optimistic and see a day when more advanced lasers will make the scalpel a thing of the past. The second of these views may prove to be the most accurate, for surgical use of lasers is rapidly advancing. At first, lasers were considered most effective in operating on areas that are easy to reach—areas on the body's exterior, including the skin, mouth, nose, ears, and eyes. But in recent years doctors have demonstrated remarkable progress in developing laser techniques for use in internal exploration and surgery.Of course, in order to be able to direct the laser beam the doctor must be able to see inside the body. In some cases this is a simple matter of making an incision and opening up the area to be operated on. But there are situations in which this step can be avoided. Cleaning Arteries with Light For instance, lasers are increasingly used to clean plaque from people's arteries. Plaque is a tough fatty substance that can build up on the inside walls of the arteries. Eventually the vessels can get so clogged that blood do es not flow normally, and the result can be a heart attack or stroke, both of which are serious and sometimes fatal.The traditional method for removing the plaque involves opening the chest and making several incisions, a long and sometimes risky operation. It is also expensive and requires weeks for recovery. An effective alternative is to use a laser beam to burn away the plaque. The key to making this work is the doctor's ability to see inside the artery and direct the beam, another area in which fiber optics and lasers are combined into a modern wonder tool. An optic fiber that has been connected to a tiny television camera can be inserted into an artery.These elements now become a miniature sensor that allows the doctor and nurses to see inside the artery while a second fiber is inserted to carry the bursts of light that will burn away the plaque. The technique works in the following way. The fiber-optic array is inserted into a blood vessel in an arm or leg and moved slowly in to the area of the heart and blocked arteries. When the array is in place the laser is fired and the plaque destroyed, and then the exhaust vapors are sucked back through a tiny hollow tube that is inserted along with the optical fibers.When the artery has been cleaned out the doctor removes the fibers and tube, and the operation is finished. This medical process is known as laser angioplasty. It has several obvious advantages. First, no incision is needed (except for the small one in the vessel to insert the fibers). There is also little or no bleeding, and the patient can enjoy total recovery in a day or two. Laser angioplasty does have some potential risks that must be considered. First, when the laser beam fires at the plaque it must be aimed very carefully ecause a slight miss could cut through the wall of the artery and cause serious bleeding. The patient's chest would then have to be opened up after all. Another problem involves small pieces of burnt debris from the Surgeons use a tiny laser to cut away tissue in a gallbladder operation. The laser and a tiny camera are inserted into the navel, so no abdominal incision is necessary. . Lasers Heal and Reshape the Eyes Some of the most remarkable breakthroughs for medical lasers have been in the area of ophthalmology, the study of the structure and diseases of the eye.One reason that laser beams are so useful in treating the eye is that the cornea, the coating that covers the eyeball and admits light into the interior of the eye, is transparent. Since it is designed to admit ordinary light, the cornea lets in laser light just as well and remains unaffected by the beam. First, the laser is very useful in removing extraneous blood vessels that can form on the retina—the thin, light-sensitive membrane at the back of the eyeball. It is on the retina that the images of the things the eye sees are formed. Damage to the retina can sometimes cause blindness.The laser most often used in the treatment of this condition is powered by a medium of argon gas. The doctor aims the beam through the cornea and burns away the tangle of blood vessels covering the retina. The procedure takes only a few minutes and can be done in the doctor's office. The laser can also repair a detached retina—one that has broken loose from the rear part of the eyeball. Before the advent of lasers detached retinas had to be repaired by hand, and because the retina is so delicate this was a very difficult operation to perform. Using the argon laser, the doctor can actually â€Å"weld† the torn retina back in place.It is perhaps a strange coincidence that Gordon Gould, one of the original inventors of the laser, later had one of his own retinas repaired this way. Another condition that affects the eye is glaucoma, which is characterized by the buildup of fluid in the eye. Normally the eye's natural fluids drain away a little at a time, and the eye stays healthy. In eyes impaired with glaucoma the fluid does not drain properly, and the buildup affects vision; blindness can sometimes result. In some cases drugs can be used to treat glaucoma. If the drugs fail, however, many doctors now turn to the laser to avoid onventional surgery. The laser punches a hole in a preplanned spot and the fluid drains out through the hole. Again, the treatment can be performed in a doctor's office instead of a hospital. Using Lasers for Eye Surgery The laser works like a sewing machine to repair a detached retina, the membrane that lines the interior of the eye. The laser beam is adjusted so that it can pass harmlessly through the lens and focus on tiny spots around the damaged area of the retina. When it is focused, the beam has the intensity to â€Å"weld† or seal the detached area of the retina back against the wall of the eyeball.The patient's eyeglass prescription is literally carved inside the cornea with the beam of an excimer laser [a laser device that produces pulses of ultraviolet, or UV, light]. A small flap of the cornea is first removed with a precision knife . . . and an A patient undergoes eye surgery performed by a laser beam. In addition to treating detached retinas, lasers can remove cataracts. inner portion of the cornea is exposed to the excimer laser. After the prescription is carved, the corneal flap that was opened is then put back into place over the ablated [surgically altered] cornea. 6 LASIK does not come without risks.The changes it makes in the cornea are permanent, and the danger of unexpected damage is ever present. However, the procedure has become increasingly popular each year; about a million Americans had it done in the year 2000, and about four thousand surgeons in the United States were trained to perform it. Some Cosmetic Uses of Lasers Medical lasers are also widely used for various types of cosmetic surgery, including the removal of certain kinds of birthmarks. Port-wine stains, reddish purple skin blotches that appear on about thre e out of every one thousand children, are an example.Such stains can mark any part of the body but are most commonly found on the face and neck. The medical laser is able to remove a port-wine stain for the same reason that a military laser is able to flash a message to a submerged submarine. Both lasers take advantage of the monochromatic quality of laser light, that is, its ability to shine in one specific color. The stain is made up of thousands of tiny malformed blood vessels that have a definite reddish purple color. This color very strongly absorbs a certain shade of green light. In fact, that is why the stain looks red.It absorbs the green and other colors in white light but reflects the red back to people's eyes. To treat the stain, the doctor runs a wide low-power beam of green light across the discolored area. The mass of blood vessels in the stain absorbs the energetic laser light and becomes so hot that it is actually burned away. The surrounding skin is a different colo r than the stain, so that skin absorbs only small amounts of the beam and remains unburned. (Of course, the burned A doctor uses an argon laser to remove a port-wine stain, a kind of birthmark.Unwanted tissue is burned away while normal skin remains undamaged. areas must heal, and during this process some minor scarring sometimes occurs. ) Laser-Assisted Dentistry Dentistry is another branch of medicine that has benefited tremendously from laser technology. Indeed, lasers have made some people stop dreading a visit to the dentist. No one enjoys having a cavity drilled, of course. It usually requires an anesthetic (a painkiller like novocaine) that causes uncomfortable numbness in the mouth; also, the sound of the drill can be irritating or even sickening to some people.Many dentists now employ an Nd-YAG laser (which uses a crystal for its lasing medium) instead of a drill for most cavities. The laser treatment takes advantage of the simple fact that the material that forms in a cavi ty is much softer than the enamel (the hard part of a tooth). The laser is set at a power that is just strong enough to eliminate the decayed tissue but not strong enough to harm the enamel. When treating a very deep cavity bleeding sometimes occurs, and the laser beam often seals off blood vessels and stops the bleeding. The most often asked question about treating cavities with lasers is: Does it hurt?The answer is no. Each burst of laser light from a dental laser lasts only thirty-trillionths of a second, much faster than the amount of time a nerve takes to trigger pain. In other words, the beam would have to last 100 million times longer in order to cause any discomfort. So this sort of treatment requires no anesthetic. Advantages of Lasers for Dental Surgery In this excerpt from an article in The Dental Clinics of North America Robert A. Strauss of the Medical College of Virginia mentions some of the advantages of using lasers for oral surgery. Decreased post-operative swelling is characteristic of laser use [for oral surgery].Decreased swelling allows for increased safety when performing surgery within the airway [the mouth] . . . and increases the range of surgery that oral surgeons can perform safely without fear of airway compromise. This effect allows the surgeon to perform many procedures in an office or outpatient facility that previously would have required hospitalization. . . . Tissue healing and scarring are also improved with the use of the laser. . . . Laser wounds generally heal with minimal scar formation and . . . often can be left unsutured [without stitches], another distinct advantage. Thus the role of laser in medical field is most predominant.

Out of Darkness Comes Light Essays

Out of Darkness Comes Light Essays Out of Darkness Comes Light Paper Out of Darkness Comes Light Paper Ten years ago Tariq couldnt have walked down Leyton high street without having at least one racist comment shouted at him. His family was driven out of Iraq because of Saddam Hussein. His father was taken hostage by a guerilla mob and is most likely dead. He found his way to Britain in the back of a lorry with his mother and his two younger sisters. When he arrived in Britain he lived in a hostel in Leytonstone with his family and his twelve year old sister had to work as a prostitute to try and earn enough money to provide for the family. His mother was ill and his youngest sister, Zahrsa had to look after her throughout the day whilst he was at school trying to get an education. He was bullied continuously at school and had one friend Marik who lived on the same estate as him. Tariqs story started like this:It was your average Tuesday night for Tariq. Hed just finished school at Tom Hood High School, where he went to school, and was making his way to the park where he always met his friend Marik, everyday after school. Mariks family was very rich and Marik went to a private school in Hertfordshire where he was bullied constantly. That was the base of their friendship, the fact that they were both the victims of bullying. Tariq made his way over to the swings in the corner of the playground, avoiding the stares from the rudeboys who were sitting on the bench the other side of the park most likely smoking cannabis. Marik was normally here first because his bus stop was just round the block but it was Tariqs turn to play the waiting game today. Tariq started to count the buses going past him on the road opposite him when Marik turned the corner.Marik made his way over to Tariq and sat down on the swing next to him.Ten years ago Tariq couldnt have walked down Leyton high street without having at least one racist comment shouted at him. His family was driven out of Iraq because of Saddam Hussein. His father was taken hostage by a guerilla mob and is most likely dead. He found his way to Britain in the back of a lorry with his mother and his two younger sisters. When he arrived in Britain he lived in a hostel in Leytonstone with his family and his twelve year old sister had to work as a prostitute to try and earn enough money to provide for the family. His mother was ill and his youngest sister, Zahrsa had to look after her throughout the day whilst he was at school trying to get an education. He was bullied continuously at school and had one friend Marik who lived on the same estate as him. Tariqs story started like this:It was your average Tuesday night for Tariq. Hed just finished school at Tom Hood High School, where he went to school, and was making his way to the park where he always met his friend Marik, everyday after school. Mariks family was very rich and Marik went to a private school in Hertfordshire where he was bullied constantly. That was the base of their friendship, the fact that they were both the victims of bullying. Tariq made his way over to the swings in the corner of the playground, avoiding the stares from the rudeboys who were sitting on the bench the other side of the park most likely smoking cannabis. Marik was normally here first because his bus stop was just round the block but it was Tariqs turn to play the waiting game today. Tariq started to count the buses going past him on the road opposite him when Marik turned the corner. Marik made his way over to Tariq and sat down on the swing next to him.

IN INSTRUCTIONS Example

IN INSTRUCTIONS Example IN INSTRUCTIONS – Coursework Example Animal Testing Animal testing is one of the most controversial issues that are still discussed worldwide. Some may even say that it is quite ubiquitous, and the debate should stop. However, there is still no simple answer to the questions concerning justification of animal testing. More so, this topic touches such spheres as religion, science and politics. I know that animal testing have been in place for centuries and it is still needed for development of science. Of course, methods used can and should be changed as sometimes animals are exposed to excessive and meaningless suffering. As far as scientists are concerned, they argue that it is impossible to move further without tests and it is better to use animals before people participation in experiments (Mason, 2015). For scientists, animal testing is the necessary evil that is crucial for achievement of the overall good. At the same time, those who fight for animals’ rights keep saying that animal testing should be complet ely banned, as animals suffer from intolerable pain. These groups exert pressure on officials and politicians who often try to satisfy their demands. Thus, the government put certain restrictions on animal testing in cleaning products production (Mason, 2015). Notably, politicians imposed partial restrictions, which led to dissatisfaction of both groups: scientists and activists. It is important to note that politicians take certain sides in their desire to win more votes. The problem affects politics in this particular way. As for religious aspects, the issue reveals certain controversy of religious beliefs and paradigms. Christianity used to have quite a specific view on the matter as animals were seen as God’s gifts that can be used in any way. At present, Christians tend to focus on such concepts as animals and people as creations of God, animals having souls and so on. Christian leaders also try to address the problem, as they need to respond to issues that arise in the society to make people feel their guidance and support.Reference ListMason, R. (2015, March 12). Animal testing restrictions are wasted opportunity, say campaigners. The Guardian. Retrieved from theguardian.com/science/2015/mar/12/animal-testing-restrictions-wasted-opportunity-campaigners

Bespoke

Bespoke Bespoke Bespoke By Maeve Maddox A reader has asked for a discussion of the word bespoke: I keep reading it in articles, and at least half the time I see it I end up looking it up because it just doesn’t seem correct to me. Bespoke is an adjective that comes from the archaic English verb bespeak. One of the meanings of the prefix be- is â€Å"about.† When miserly Samuel Pepys dreads that a man wants him to be his son’s godfatheran honor that would require some outlay of cashhe says, [The man] who I feared did come to bespeak me to be godfather to his son. That is, â€Å"who he feared had come to speak to him about the prospect of his standing godfather.† In early usage bespeak could also mean â€Å"to speak out,† â€Å"to ask for,† â€Å"to tell about,† and â€Å"to predict,† as well as the meaning that has survived in the bespoke of the reader’s question: â€Å"to engage beforehand; to order goods.† Bespoke and bespoken are past forms of bespeak. For example, A new set of chains was bespoke. (A new set of chains was ordered.) She had arranged or bespoken to have him killed. (She had talked about a hit.) In its current use as an adjective, bespoke refers to custom-made goods in contrast to goods that are ready-made. The adjective can also refer to a person who provides such goods, (e.g., â€Å"a bespoke tailor†). In England the expression â€Å"bespoke suit† is a common way of referring to a tailor-made suit. In the context of conspicuous consumption, bespoke seems to have something to do with the desires of hedonists who don’t know what to do with their money. Watchmakers look to bespoke design to court the super-rich: We will offer a bespoke service where the customer has a say on everything: the material, the case, the dial, the hands, said Thierry Andretta, president of the firm where prices for custom-made watches start at 100,000 Swiss francs ($113,000). Gourmet dining, private flights, bespoke safaris, slimming clinics and art auctions emerging as top status symbols The Privileged World City: Private Banking, Wealth Management and the Bespoke Servicing of the Global Super-Rich American speakers of less extravagant means and tastes are more likely to refer to the things they special-order as â€Å"custom-made.† Want to improve your English in five minutes a day? Get a subscription and start receiving our writing tips and exercises daily! Keep learning! Browse the Expressions category, check our popular posts, or choose a related post below:75 Contronyms (Words with Contradictory Meanings)The Possessive ApostropheParticular vs. Specific

The Rise of American Industry- American Economic History Research Proposal

The Rise of American Industry- American Economic History - Research Proposal Example Although America has been blessed with abundant geological resources, the intensity of conversion of natural resources into manufactured commodities, which grew the most during 1880 to 1920, was the major reason that American industry could grow to this predominance. Economies of scale and capital intensive production was possible because of the access to new materials like aluminum and copper as well as larger markets through the transportation network (Chandler, 1992). This enabled the American industry to get a competitive advantage in the period prior to the First World War. During the inter-war years, 1929-41, the American economy witnessed the worst recession and unemployment situation as a result of demand crash, hence the period popularly known as the Great Depression. The economy recovered after the Second World War and the period between 1948 and 1973 was a boom time, with private non-farm enterprises growing fast. Interestingly, even during the depression years, growth in real output was higher than the growth in real wages and real capital, that is total factor productivity (TFP) grew faster than in the post-war boom years. Some economists have argued that this simultaneous existence of high labor productivity and unemployment stems from the fact that with decline in demand, private enterprises tended to lay off the unproductive labor. Hence, selective labor retention and improved management practices enabled higher labor productivity. However, other economists have found that factors other than selective retention of labor resulted in the high inter-war productivity growth, which was the base on which post-war economic revival happened in America. For example, quality of labor improved as Americans received better educational qualifications during the inter-war years, a level that was not achieved again since the 1960s (Goldin, cited in Field, 2006). On

Managing Workplace Diversity Assignment Example | Topics and Well Written Essays - 500 words - 1

Managing Workplace Diversity - Assignment Example 2. If the organization has a community fundraiser, we would definitely elect a person from that very particular community to lead the initiative. This decision should be made because it is a person from that community who has a deeper understanding of his people and communal needs. Besides, the involvement of a person from the community would appeal to the local community members to accept and support the initiative as their own project. 3. Once I realize that an employee is not descent, I would have to call him, privately, in my office and interrogate him. After letting him know that the organization tolerates diverse cultures, I would tell him that the company has a set of personal etiquette such as descent dressing codes that everyone should abide by. This will be done in a polite manner. 2) This story has taught me that the Native Americans were charitable people. As stated in the story, they valued thanksgiving because it was allowed by their religion. Although they had considered the Puritans as their enemies, they did not mind putting aside their differences while celebrating thanksgiving. They must have been a friendly