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61.
Young Sun Mok Sung Won Ham In-Sik Nam 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1998,26(5):1566-1574
A mathematical model was proposed to describe the behaviour of the removal of nitrogen oxides (NOx) in a positive pulsed corona discharge reactor. The proposed model takes into account radical production at each pulsing and subsequent radical utilization for NOx removal. The production efficiencies of radicals such as O, OH, H, and N were derived by considering direct electron impact on dissociation of gaseous molecules, followed by excitation transfer reactions of excited oxygen atoms. The production efficiencies of those species were used for the model calculations. The proposed model could adequately predict the experimental data. Of the active species present, the ozone (O3) produced by the reaction of O radical with oxygen was found to play the crucial role in oxidation of NO to NO2 , both theoretically and experimentally 相似文献
62.
Ahn JH Jung SH Kim JA Song SB Kwon SJ Kim KR Rhee SD Park SD Lee JM Kim SS Cheon HG 《Chemical & pharmaceutical bulletin》2005,53(8):1048-1050
In the continuation of efforts to modify the structure of our novel DP-IV inhibitors, a series of pyrazolidine derivatives with heteroaryl urea was synthesized and evaluated for their ability to inhibit dipeptidyl peptidase IV (DP-IV). 相似文献
63.
Laser-induced fluorescence spectrum of TiS in the 769-863 nm region has been recorded and analyzed. The TiS molecule was produced using the technique of laser vaporization/reaction with supersonic cooling. Twenty-one weak subbands have been assigned as being due to b(1)Pi-X(3)Delta, B(3)Pi(0)-X(3)Delta(1), and C(3)Delta-X(3)Delta transitions. Strong evidence shows that the b(1)Pi state is responsible for perturbing the v = 0, 1, and 2 levels of the C(3)Delta(1) subband. The molecular constants of the b(1)Pi state have been determined as follows: T(e) = 10 589.47 cm(-1), omega(e) = 542.14 cm(-1), omega(e)x(e) = 3.16 cm(-1), B(e) = 0.19568 cm(-1), and alpha(e) = 0.00085 cm(-1). The spin-orbit interaction between the b(1)Pi (v = 2 and 3) and C(3)Delta (v = 1 and 2) levels is discussed in terms of configuration interaction occurring between the b(1)Pi from the 11varsigma(1) 5pi(1) configuration and the (1)Pi from the 5pi(1) 1delta(1) configuration, and the C(3)Delta state from 12varsigma(1) 1delta(1) configuration. Copyright 2000 Academic Press. 相似文献
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Experimental determinations of the frequency dependence of the anharmonic self-energy shift and damping of the q ? 0 transverse optic mode in KBr at 300 and 100 K are presented. The room temperature measurements of the damping function are shown to be in good agreement with recent calculations by Bruce which include a contribution from a term reflecting the three phonon density of states. 相似文献
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S. M. Rao M. K. Wu J. K Srivastava B. H. Mok N. Y. Yen H. Y. Lin H. Y. Tang M. C. Ling H. L. Liu 《Crystal Research and Technology》2006,41(9):859-864
Single crystals of Sr2YRu1‐xCuxO6 (x = 0 ‐ 0.4) have been grown from PbO‐PbF2 based solutions in the temperature range 1150 – 1350°C. A silicon carbide heating element furnace (with a recrystallized alumina tube lining) in a vertical configuration was used to grow the crystals in platinum crucibles. Conditions for the stable growth of big crystals have been investigated. The morphology of the crystals containing Cu was found to change from octahedral to cube octahedral as the growth temperature is increased from 1150 to 1350°C. Crystals measuring up to 4.5 mm across and 2.5 mm thick have been grown from 1250°C. The incorporation of Cu into the crystals was ascertained by EDS and x‐ray diffraction analysis. A diamagnetic transition which increased in magnitude and temperature with x was observed. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Glass transition temperature (Tg) breadths are reported for polystyrene (PS) micelle cores in two series of micelle‐forming block copolymers [PS‐poly(ethylene oxide) and PS‐poly(methyl methacrylate)] with an ionic liquid solvent (1‐ethyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)amide). An increased level of fluorescent molecules was induced within the cores upon rapid cooling followed by aging. Using fluorescence to monitor dye release with relaxation of this state upon heating, transition onset and end‐point temperatures were defined. The system with the lowest PS‐block molecular weight showed no evidence of a transition above 25 °C; however, in every other case, transitions were observed beginning at ~40‐45 °C and ending at ~60‐85 °C. These temperatures closely match PS‐block Tg results measured by differential scanning calorimetry in semidilute solutions of the same materials, suggesting that the transition temperature range correlates strongly to the transition of the cores from fully glassy to fully rubbery. Differences in transition end‐points were related to PS‐block molecular weights and relative copolymer fractions of PS. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献
70.
Taewook Kang Jae Ho Kim Ingie Hong Nanhyun Park Helmut Heinsen Joo-Yong Lee Rivka Ravid Isidro Ferrer Jong Shin Yoo Kyung-Hoon Kwon Young Mok Park 《Analytical and bioanalytical chemistry》2014,406(22):5433-5446
Posttranslational modifications modulate protein function in cells. Global analysis of multiple posttranslational modifications can provide insight into physiology and disease, but presents formidable challenges. In the present study, we used a technique that does not require target enrichment to analyze alterations in the phosphorylation and ubiquitination of proteins from patients with Alzheimer’s disease (AD). Guided by our previous findings, we applied three strategies to further our understanding of the dysregulation of posttranslationally modified proteins. We first identified phosphorylation sites by determining peptide pI shifts using OFFGEL. Second, using tandem mass spectrometry, we determined the ubiquitination status of the proteins using an assay for a trypsin digestion remnant of ubiquitination (Gly-Gly). Third, for large-scale discovery, we quantified the global differences in protein expression. Of the proteins expressed in AD tissue at levels of 2.0 or greater compared with controls, 60 were phosphorylated and 56 were ubiquitinated. Of the proteins expressed at levels of 0.5 or lower compared with controls, 81 were phosphorylated and 56 were ubiquitinated. Approximately 98 % of the phosphopeptides exhibited a pI shift. We identified 112 new phosphorylation sites (51.38 %), and 92 new ubiquitination sites (96.84 %). Taken together, our findings suggest that analysis of the alterations in posttranslationally modified proteins may contribute to understanding the pathogenesis of AD and other diseases. 相似文献