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1.
We present a new experimental determination of the Compton profiles of CH4 and C2H4 molecules using high energy electron impact. The observable q range has been extended up to 10 au (6 au for C2H4). Good agreement is found with an earlier X-ray scattering experiment and with new theoretical calculations.  相似文献   
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Research on Chemical Intermediates - The objective of this work is to test the effectiveness of hydrotalcite as an adsorbent for the retention of nitrate and nitrite ions and to study the influence...  相似文献   
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An efficient and facile method for the synthesis of novel structurally diverse β-amino dicarbonyl compounds is described by exploring the aza-Michael addition reaction in an aqueous medium as a key step. Thereby, 2-(aryl-disubstituted-amino-1-yl-methyl)-malonic acid diethyl esters were achieved in a good to excellent yields. These products were easily isolated with enough purity just by using simple recrystallization. The crystals of the compounds (17) and (24) have been obtained and studied by X-ray crystallographic analyses.  相似文献   
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Using a 35 keV electron beam incident on NH3, precision measurements of the energy loss position of the Compton peak have been performed. The observed Compton peak is found to be at larger energy losses than predicted for an electron scattered through the same angle from a stationary unbound electron. This defect has been studied for the momentum transfer range 0.5 au < K < 11 au, and is shown to be nonzero even at large K values. A sudden increase in the magnitude of the defect is observed when the inner electrons start contributing to the maximum of the Compton profile. This could suggest the possibility that the defect is related to the binding energies of the target electrons.  相似文献   
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Abstract  

The title compound, 3-(4-methoxy-benzylidene)-isothiochroman-4-one (C17H14O2S) was prepared from the reaction of isothiochroman-4-one with benzaldehyde in the presence of small amount of HCl. The structure of the synthesised compound was determined by IR, 1H NMR and X-ray crystallography. The structure was solved in monoclinic, space group P21/n with a = 3.9773 (7) Å, b = 10.918 (2) Å, c = 30.609 (6) Å, β = 90.615 (3)°, V = 1329.1 (4) Å3, Z = 4 and with R int = 0.047. The bicyclic ring of isothiochroman-4-one moiety does not adopt a planar geometry. The molecular conformation is stable via C10–H···O1 and C16–H···S1 intramolecular hydrogen-bonding interactions. These contacts involve molecules in an extended two-dimensional sheet to the bc plane.  相似文献   
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GT-2331 is a potent histamine H(3) antagonist which has entered clinical trials. Efficient multigram syntheses of this compound and its enantiomer are described. The literature reports that GT-2331 is the dextrorotatory (+), more potent, enantiomer of 4-[2-(5,5-dimethylhex-1-ynyl)cyclopropyl]-1H-imidazole with the absolute configuration of (1R,2R)-1. However, we found that the dextrorotatory, more potent, enantiomer of 4-[2-(5,5-dimethylhex-1-ynyl)cyclopropyl]-1H-imidazole has the (1S,2S) absolute configuration. We suggest a reconsideration of the absolute configuration of GT-2331.  相似文献   
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a-C∶H films have been deposited from methane in a 20 KHz discharge. The Current Voltage characteristics of the plasma have been plotted as a function of the CH4 pressure. It was shown that below 0.1 mbar the graphitic content in the films estimated from Raman Spectroscopy and Electron Energy Loss Spectroscopy is high enough to give electrical conductivity controlled by a percolation mechanism. It was also found that the a:c electrical responses of the deposited films are more sensitive to the structure than any other chemical analysis. The electrical analysis might be a good tool for structural investigations on a-C∶H films.  相似文献   
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