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31.
Tamás?Kovács Tamás?Turányi Katalin?F?gleinEmail author János?Szépv?lgyi 《Plasma Chemistry and Plasma Processing》2005,25(2):109-119
Decomposition of carbon tetrachloride in a RF thermal
plasma reactor was investigated in argon atmosphere. The net
conversion of CCl4 and the main products of its decomposition
were determined from the mass spectrometric analysis of outlet
gases. Flow and temperature profiles in the reactor were
calculated and concentration profiles of the species along the
axis of the reactor were estimated using a newly developed
chemical kinetic mechanism, containing 12 species and 34 reaction
steps. The simulations indicated that all carbon tetrachloride
decomposed within a few microseconds. However, CCl4 was partly
recombined from its decomposition products. The calculations
predicted 70\% net conversion of CCl4, which was close to the
experimentally determined value of 60\%. A thermodynamic
equilibrium model also simulated the decomposition. Results of the
kinetic and thermodynamic simulations agreed well above 2000 K.
However, below 2000 K the thermodynamic equilibrium model gave
wrong predictions. Therefore, application of detailed kinetic
mechanisms is recommended for modeling CCl4 decomposition under
thermal plasma conditions. 相似文献
32.
33.
Ying Han Katalin Ebinger Jennifer W. Maloney Harold N. Weller 《Tetrahedron letters》2010,51(4):629-4502
A new, divergent, efficient, and selective synthesis of furo- and thieno[2,3-d]pyrimidin-4-amine derivatives by microwave irradiation has been developed starting from readily available amines and substituted 2-aminofuran-3-carbonitrile or 2-aminothiophene-3-carbonitrile, which are converted into corresponding formamidines in DMF using benzenesulfonyl chloride. 相似文献
34.
35.
One-bond heteronuclear and two-bond homonuclear residual dipolar couplings measured at methylene or amine sites can be utilized as long-range constraints in structure determination of molecules as well as to facilitate characterization of local conformation by stereospecific assignment of diastereotopic protons. We present two J-modulated HMQC type experiments to measure the one-bond heteronuclear dipolar coupling contributions of geminal protons individually. In addition two-bond homonuclear residual dipolar couplings between the diastereotopic protons are also obtained. 相似文献
36.
Bark T von Zelewsky A Rappoport D Neuburger M Schaffner S Lacour J Jodry J 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(19):4839-4845
The hexadentate, and ditopic ligand 2,5-bis([2,2']bipyridin-6-yl)pyrazine yields a chiral, tetrameric, square-shaped, self-assembled species upon complexation with Fe2+ ions. The racemate of this complex was resolved with antimonyl tatrate as the chiral auxiliary. The purity of the enantiomer was determined by NMR spectroscopy, by using a chiral, diamagnetic shift reagent, and by circular dichroism (CD). The CD spectrum was also calculated by time-dependent density functional theory, and the correlation that was found between CD spectrum and configuration was confirmed by X-ray cristallography. When a "chiralised" version of the ligand was used instead, the corresponding iron complex was obtained in diastereomerically pure form. 相似文献
37.
Bergen HR Ajtai K Burghardt TP Nepomuceno AI Muddiman DC 《Rapid communications in mass spectrometry : RCM》2003,17(13):1467-1471
Skeletal and cardiac muscle contains actin isoforms that vary by two juxtaposed amino acids and two amino acid substitutions (Met299Leu and Ser358Thr). This close sequence homology does not allow cardiac and skeletal actin isoforms to be resolved in traditional SDS-PAGE analysis as the molecular weights (Deltamass = 32 Da) are not significantly different and the pIs are identical (5.2). Although cardiac actin is the predominant form in cardiac muscle, there appears to be a specific skeletal/cardiac actin ratio in a normal heart that may vary in a compromised or diseased heart. In an effort to ascertain the validity of this hypothesis we developed a mass spectrometric technique to measure the ratio of skeletal to cardiac actin. The technique involves purification of muscle actin and subsequent liquid chromatography coupled with electrospray ionization Fourier transform ion cylcotron resonance (LC/FTICR-MS) mass spectrometry. A 7 Tesla FTICR mass spectrometer was utilized to compare skeletal/cardiac actin isoform ratios. Additionally, a new dual electrospray ionization source was employed to determine accurate masses of the alpha-skeletal and alpha-cardiac actins. 相似文献
38.
K. Gruiz M. Moln��r E. Fenyvesi Cs. Hajdu ��. Atk��ri K. Bark��cs 《Journal of inclusion phenomena and macrocyclic chemistry》2011,70(3-4):299-306
Experimental results, which may serve as basis for innovative applications of cyclodextrins (CDs) in environmental technologies, are presented here. Some newly developed CD-aided tools are used in sampling, measuring the concentration or testing the effect of contaminants in water and soil. The innovative methods such as the bacterial bioassays with CD-increased sensitivity or the CD-filled absorptive samplers for air and water sampling are utilised in environmental exposure, hazard and risk assessment. Technological developments aim the reduction of the risk of chemical substances in waters and soils. CD-aided environmental remediation is introduced through examples for the elimination of organic contaminants from water by CD-filters, and for the enhancement of the mobility and availability of soil contaminants in this way increasing the efficiency of soil remediation by water extraction, chemical oxidation, biodegradation, etc. 相似文献
39.
E. Beckmann E. Bark N. Zuntz W. Lenz Berthelot Jungfleisch und A. A. Jakowkin 《Fresenius' Journal of Analytical Chemistry》1917,56(5):262-266
Ohne Zusammenfassung 相似文献
40.