A phase transfer catalyst or PTC in chemistry is a catalyst which facilitates the migration of a reactant in a heterogeneous system from one phase into another phase where reaction can take place. Ionic reactants are often soluble in an aqueous phase but insoluble in an organic phase unless the phase transfer catalyst is present. Phase transfer catalysis (also PTC) refers to the acceleration of the reaction by the phase transfer catalyst. Phase transfer catalysts for anion reactants are often
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Title: Trurl’s Machine Author: Stanislaw Lem As a boy Stanislaw Lem showed an early interest in science as well as in the imaginary worlds of fantasy and science fiction. The young Lem’s interest in tinkering mechanical devices of all sorts was put to use by secretly damaging the German vehicles during the Nazi occupation. Later on‚ he became a full time writer establishing himself as leading science fiction writer in Eastern Europe. This writer from Lvov Poland (now Ukraine) worked on serious
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Man Man and the Machine “Man‚ “Man‚ biologically considered… … is the most formidable of all the beasts of pray‚ and indeed‚ the only one that preys systematically on its own species” William William James (Memories and Studies) From the aeon of the history‚ we have perceived that man has been developing at jet speed in the fields of science and technology. Man‚ who once lived in the forest‚ in the natural state‚ is now on the cliff of mechanical advancement. The question arises today
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“Darwin among the Machines‚” 46 years before Forster (whose story‚ “The Machine Stops‚” was published 107 years ago). It is hard to believe that two stories with a similar tone could have been written so long ago. What is even more incredible is that they both seem to relate to present day society. How could two people (both from a time when technology was in its infancy) could write stories that could have been written about our time or even in our near future? The concept that machines will surpass
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now. To properly observe and describe the breakdown of the hop‚ skip‚ and jump phases‚ while determining the muscles that cause these movements. The triple jump‚ referred to as the hop‚ skip and jump‚ is a track and field event similar to the long jump. The only difference between the two is that the hop‚ skip‚ and jump involve a hop and a step‚ whereas the long jump involves just a jump. In the first phase of the triple jump‚ the competitor builds momentum by sprinting down the runway
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Two-Variable Inequality (YOUR NAME HERE) MAT 221 (YOUR PROFESSOR ’S NAME HERE) February 10‚ 2014 Two-Variable Inequality We use inequalities when there is a range of possible answers for a situation. That’s what we are interested in when we study inequalities‚ possibilities. We can explore the possibilities of an inequality using a number line which is sufficient in simple situations‚ such as inequalities with just one variable. But in more complicated circumstances‚ like those with two variables
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1-Introduction In John F. Kasson’s “Civilizing the Machine‚” Kasson enlightens his audience that cities did not create factories‚ factories created cities. During the dawn of the British Industrial Revolution‚ the Americans began to adopt their own form of this event through the creations of factories and water-powered generators which‚ at the beginning of the time‚ revolved around the New England/ Boston area. Kasson explains through his article of the various entrepreneurs who founded these first
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The second phase and the third phase of the iconographical development of Yaksha both took place during the Satavahana-Kushana Phase‚ which is from the first century BC to the second century AD‚ and it kept on going till the end of fourth century AD. Since the two phases happened in the same broad historical period‚ it might be useful to discuss them in the same section together. The style of the second phase is the dwarf-like‚ monstrous type that are commonly found on the railing-pillars of stupa
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The three major phases of Reconstruction were Wartime Reconstruction which took place from 1861-1865‚ Presidential Reconstruction from 1865-1867‚ and Congressional or Radical Reconstruction which took place between 1867-1877. During these periods‚ the war was still underway and President Lincoln felt the need to build up the south with a resilient Republican party to bring an end to the animosity caused by war. He worked to insure that the state approved the Thirteenth Amendment and abolish slavery
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ELECTRONIC VOTING MACHINE 1. What is an Electronic Voting Machine? It is a simple electronic device used to record votes in place of ballot papers and boxes which were used earlier in conventional voting system. 2. What are the advantages of EVM over the traditional ballot paper/ballot box system? (i) It eliminates the possibility of invalid and doubtful votes which‚ in many cases‚ are the root causes of controversies and election petitions. (ii) It makes the process of counting of votes much
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