存储一些密码字典（其实就是水仓库的，以后再水一些其他的分享之类的） We value excellent academic writing and strive to provide outstanding essay writing service each and every time you place an order. We write essays, research papers, term papers, course works, reviews, theses and more, so our primary mission is to help you succeed academically Cynthia Ann McKinney (born March 17, ) is an American politician and assistant professor at North South University, Bangladesh. As a member of the Democratic Party, she served six terms in the United States House of blogger.com was the first African American woman elected to represent Georgia in the House. She left the Democratic Party and ran in as the presidential candidate
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Robert Burns Woodward ForMemRS HonFRSE April 10, newt gingrich phd dissertation, — July 8, was an American organic newt gingrich phd dissertation. He is considered by many to be the most preeminent synthetic organic chemist of the twentieth century, [3] having made many key contributions to the subject, especially in the synthesis of complex natural products and the determination of their molecular structure.
He also worked closely with Roald Hoffmann on theoretical studies of chemical reactions. He was awarded the Nobel Prize in Chemistry in Woodward was born in Boston, Massachusettson 10 April He was the son of Margaret Burns an immigrant from Scotland who claimed to be a descendant of the poet, Robert Burns and her husband, Arthur Chester Woodward, himself the son of Roxbury apothecary, Harlow Elliot Woodward.
His father was one of the many victims of the Spanish flu pandemic of From a very early age, Woodward was attracted to and engaged in private study of chemistry while he attended a public primary school, and then Quincy High School[4] in Quincy, Massachusetts. By the time he entered high school, he had already managed to perform most of the experiments in Ludwig Gattermann 's then widely used textbook of experimental organic chemistry. InWoodward contacted the Consul-General of the German consulate in Boston Baron von Tippelskirch [5]and through him, managed to obtain copies of a few newt gingrich phd dissertation papers published in German journals.
Later, in his Cope lecture, he recalled how he had been fascinated when, among these papers, he chanced upon Diels and Alder's original communication about the Diels—Alder reaction. Throughout his career, Woodward was to repeatedly and powerfully use and investigate this reaction, both in theoretical and experimental ways.
Innewt gingrich phd dissertation entered the Massachusetts Institute of Technology MITbut neglected his formal studies badly enough to be excluded at the end of the fall term. MIT readmitted him in the fall term, and by he had received the Bachelor of Science degree. Only one year later, MIT awarded him the doctoratewhen his classmates were still graduating with their bachelor's degrees.
Woodward's advisors were James Flack Norris and Avery Adrian Morton, [ citation needed ] although it is not clear whether he actually took any of their advice. After a short postdoctoral stint at the University of Illinois, he took a Junior Fellowship at Harvard University from toand remained at Harvard in various capacities for the rest of his life.
In the s, Woodward was named Donner Professor of Science, a title that freed him from teaching formal courses so that he could devote his entire time to research.
The first major contribution of Woodward's career in the early s was a series of papers describing the application of ultraviolet spectroscopy in the elucidation of the structure of natural products. Woodward collected together a large amount of empirical data, and then devised a series of rules later called the Woodward's ruleswhich could be applied to finding out the structures of new natural substances, as well as non-natural synthesized molecules.
The expedient use of newly developed instrumental techniques was a characteristic Woodward exemplified throughout his career, and it marked a radical change from the extremely tedious and long chemical methods of structural elucidation that had been used newt gingrich phd dissertation then.
Inwith his post doctoral researcher, William von Eggers DoeringWoodward reported the synthesis of the alkaloid quinineused to treat malaria. Although the synthesis was publicized as a breakthrough in procuring the hard to get medicinal compound from Japanese occupied southeast Asia, in reality it was too long and tedious to adopt on a practical scale. Nevertheless, it was a landmark for chemical synthesis. Woodward's particular insight in this synthesis was to realise that the German chemist Paul Rabe had converted a precursor of quinine called quinotoxine to quinine in Hence, a synthesis of quinotoxine which Woodward actually synthesized would establish a route to synthesizing quinine.
When Woodward accomplished this feat, organic synthesis was still largely a matter of trial and error, and nobody thought that such complex structures could actually be constructed. Woodward showed that organic synthesis could be made into a rational science, and that synthesis could be aided by well-established principles of reactivity and structure.
This synthesis was the first one in a series of exceedingly complicated and elegant syntheses that he would undertake. Culminating in the s, the British chemists Christopher Ingold and Robert Robinson among others had investigated the mechanisms of organic reactions, and had come up with empirical rules which could predict reactivity of organic molecules.
Woodward was perhaps the first synthetic organic chemist who used these ideas as a predictive framework in synthesis. Woodward's style was the inspiration for the work of hundreds of successive synthetic chemists who synthesized medicinally important and structurally complex natural products. During the late s, Woodward synthesized many complex natural products including quininecholesterolcortisonestrychninelysergic acidreserpinechlorophyllcephalosporinand colchicine.
Many newt gingrich phd dissertation Woodward's syntheses were described as spectacular by his colleagues and before he did them, it was thought by some that it would be impossible to create these substances in the lab. Woodward's syntheses were also described as having an element of art in them, and since then, synthetic chemists have always looked for elegance as well as utility in synthesis.
His work also involved the exhaustive use of the then newly developed techniques of infrared spectroscopy and later, nuclear magnetic resonance spectroscopy. Another important feature of Woodward's syntheses was their attention to stereochemistry or the particular configuration of molecules in three-dimensional space.
Most natural products of medicinal importance newt gingrich phd dissertation effective, for example as drugs, only when they possess a specific stereochemistry. This creates the demand for ' stereoselective synthesis ', producing a compound with a defined stereochemistry. While today a typical synthetic route routinely involves such a procedure, Woodward was a pioneer in showing how, newt gingrich phd dissertation, with exhaustive and rational planning, one could conduct reactions that were stereoselective.
Many of his syntheses involved forcing a molecule into a certain configuration by installing rigid structural elements in it, another tactic that has become standard today. In this regard, especially his syntheses of reserpine and strychnine were landmarks. During World War II, Woodward was an advisor to the War Production Board on the penicillin project. Although often given credit for proposing the beta- lactam structure of penicillinnewt gingrich phd dissertation, it was actually first proposed by newt gingrich phd dissertation at Merck and Edward Abraham at Oxford and then investigated by other groups, as well e.
Woodward at first endorsed an incorrect tricyclic thiazolidine fused, amino bridged oxazinone structure put forth by the penicillin group at Peoria. Subsequently, he put his imprimatur on the beta- lactam structure, all of this in opposition to the thiazolidine — oxazolone structure proposed by Robert Robinsonthe then leading organic chemist of his generation. Ultimately, the beta-lactam structure was shown to be correct by Dorothy Hodgkin using X-ray crystallography in Woodward also applied the technique of infrared spectroscopy and chemical degradation to determine the structures of complicated molecules.
Notable among these structure determinations were santonic acidstrychninemagnamycin and terramycin. In each one of these cases, Woodward again showed how rational newt gingrich phd dissertation and chemical principles, combined with chemical intuition, could be used to achieve the task.
In the early s, Woodward, along with the British chemist Geoffrey Wilkinsonthen at Harvard, postulated a novel structure for ferrocenea compound consisting of a combination of an organic molecule with iron.
Remarkably, Woodward himself thought so, and voiced his thoughts in a letter sent to the Nobel Committee. Woodward won the Nobel Prize in for his synthesis of complex organic molecules, newt gingrich phd dissertation. He had been nominated a total of times from to In the early s, Woodward began work on what was the most complex natural product synthesized to date— vitamin B In a remarkable collaboration with his colleague Albert Eschenmoser in Zurich, a team of almost one hundred students and postdoctoral workers worked for many years on the synthesis of this molecule.
The work was finally published inand it marked a landmark in the history of organic chemistry. The synthesis included almost a hundred steps, and involved the characteristic rigorous planning and analyses that had always characterised Woodward's work, newt gingrich phd dissertation.
This work, more than any other, convinced organic chemists that the synthesis of any complex substance was possible, given enough time and planning see also palytoxinsynthesized by the research group of Yoshito Kishione of Woodward's postdoctoral students, newt gingrich phd dissertation. As ofno other total synthesis of Vitamin B 12 has been published.
That same year, based on observations that Woodward had made during the B 12 synthesis, he and Roald Hoffmann devised rules now called the Woodward—Hoffmann rules for elucidating the stereochemistry of the products of organic reactions. The predictions of these rules, called the " Woodward—Hoffmann rules " were verified by many experiments.
Hoffmann shared the Nobel Prize for this work along with Kenichi Fukuia Japanese chemist who had done similar work using a different approach; Woodward had died in and Nobel Prizes are not awarded posthumously. While at Harvard, Woodward took on the directorship of the Woodward Research Institutebased newt gingrich phd dissertation BaselSwitzerland, in Woodward died in Cambridge, Massachusettsfrom a heart attack in his sleep, newt gingrich phd dissertation.
At the time, he was working on the synthesis of an antibioticerythromycin. A student of his said about him:. During his lifetime Woodward authored or coauthored almost publications, of which 85 are full papers, the remainder comprising preliminary communications, the text of lectures, and reviews. The pace of his scientific activity soon outstripped his capacity to publish all experimental details, and much of the work in newt gingrich phd dissertation he participated was not published until a few years after his death.
Woodward trained more than two hundred Ph. students and postdoctoral workers, many of whom later went on to distinguished careers. Some of his best-known students include Robert M. Williams Colorado StateHarry Wasserman YaleYoshito Kishi HarvardStuart Schreiber HarvardWilliam R. Roush Scripps-FloridaSteven A. Benner UFJames D. Wuest Montrealnewt gingrich phd dissertation, Christopher S. Foote UCLAKendall Houk UCLAporphyrin chemist Kevin M. Smith LSUThomas R. Hoye University of MinnesotaRonald Breslow Columbia University and David Dolphin UBC, newt gingrich phd dissertation.
Woodward had an encyclopaedic knowledge of chemistry, and an extraordinary memory for detail. For his work, Woodward received many awards, honors and honorary doctorates, including election to the National Academy of Sciences inand membership in academies around the world.
He was also a consultant to many companies such as Polaroid, Pfizernewt gingrich phd dissertation, and Merck. Other awards include:. Woodward also received over twenty honorary degreesnewt gingrich phd dissertation, [19] including honorary doctorates from the following universities:.
In he married Irja Pullman; they had two daughters: Siiri Anna b. Inhe married Eudoxia Mulleran artist and technician whom he met at the Polaroid Corp.
This marriage, which lasted untilproduced a daughter, and a son: Crystal Elisabeth b. His lectures frequently lasted for three or four hours. Typically, to begin a lecture, Woodward would arrive and lay out two large white handkerchiefs on the countertop.
Upon one would be four or five colors of chalk new piecesneatly sorted by color, in a long row. Upon the other handkerchief would be placed an equally impressive row of cigarettes. The previous cigarette would be used to light the next one. His Thursday seminars at Harvard often lasted well into the night. He had a fixation with blue, newt gingrich phd dissertation, and many of his suits, his car, and even his parking space were coloured in blue.
There it hung for some years newt gingrich phd dissertation suntil scorched in a minor laboratory fire. From Wikipedia, the free encyclopedia. American chemist. For other people named Robert Woodward, see Robert Woodward disambiguation. BostonMassachusettsU.
An Evening with Hon. Newt Gingrich The Virtues of Capitalism and Free Markets
, time: 59:39Robert Burns Woodward - Wikipedia
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