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用相对论有效原子实势 (RECP)和密度泛函 (B3LYP SDD)方法研究了UH ,UH2 基态和低激发态的结构和势能函数 ,导出了分子的光谱数据 .结果表明 ,UH和UH2 的基电子状态分别为X4 Π和X3A2 ,离解能分别为 2 .886eV和5 .2 4 9eV ,UH2 具有C2v对称性 ,得到了UH和UH2 的几个不同的低激发态的结构与光谱数据 .应用多体项展式理论以及数字拟合方法 ,计算得到了UH分子和基态UH2 三原子分子的分析势能函数 ,该函数正确反映了UH和UH2分子的结构特征 ,可用于研究UHH的微观反应动力学 . 相似文献
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Fin materials can be observed in a variety of engineering applications. They are used to ease the dissipation of heat from a heated wall to the surrounding environment. In this work, we consider a nonlinear fin problem with temperature-dependent thermal conductivity and heat transfer coefficient. The equation(s) under study are highly nonlinear. Both the thermal conductivity and the heat transfer coefficient are given as arbitrary functions of temperature. Firstly, we consider the Lie group analysis for different cases of thermal conductivity and the heat transfer coefficients. These classifications are obtained from the Lie group analysis. Then, the first integrals of the nonlinear straight fin problem are constructed by three methods, namely, Noether’s classical method, partial Noether approach and Ibragimov’s nonlocal conservation method. Some exact analytical solutions are also constructed. The obtained result is also compared with the result obtained by other methods. 相似文献
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Anna N. Kondakova Evgeny Vinogradov Ewa Katzenellenbogen Nina A. Kocharova Buko Lindner Yuriy A. Knirel 《Journal of carbohydrate chemistry》2013,32(5):298-315
Core oligosaccharides were released by mild acid hydrolysis of the lipopolysaccharides of 25 strains of bacteria Citrobacter representing 19 O-serogroups. Screening by sugar analysis and high-resolution ESI MS revealed structural heterogeneity of the core within each strain and core structure variations between strains. The core oligosaccharides from Citrobacter werkmanii O14 strains PCM 1548 and 1549 were further purified by anion-exchange chromatography and their full structures were elucidated by methylation analysis and two-dimensional NMR spectroscopy; similar inner core regions and significantly different outer core pentasaccharide regions were established. D-Galacturonic acid 3-(2-aminoethyl)phosphate was found to be a characteristic component of the Citrobacter core. 相似文献
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Arbatsky N. P. Wang Min Turdymuratov E. M. Kondakova A. N. Shashkov A. S. Knirel Yu. A. 《Russian Chemical Bulletin》2015,64(5):1192-1195
Russian Chemical Bulletin - Partially O-acetylated fructan was isolated by phenol—water extraction of cells of Cronobacter dublinensis G2732 followed by anion-exchange chromatography on... 相似文献
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Anna N. Kondakova Evgeny Vinogradov Buko Lindner Nina A. Kocharova Antoni Rozalski Yuriy A. Knirel 《Journal of carbohydrate chemistry》2013,32(6):499-520
Enterobacteria of the genus Providencia are opportunistic pathogens causing diarrhea in travelers and children. Lipopolysaccharide (LPS) is the major surface antigen of Providencia and the major target of the immune response. O‐polysaccharide structures have been elucidated in several Providencia O‐serogroups, but little is known about the LPS core structure. We isolated core oligosaccharides from the R‐type LPS of a number of Providencia O‐serogroups and studied them by high‐resolution mass spectrometry, including capillary skimmer dissociation technique; three selected oligosaccharides were analyzed also by NMR spectroscopy. The conserved inner core and variable outer core regions were distinguished and the full core oligosaccharide structures established in Providencia O8, O35, and O49. Providencia LPSs were found to share some structural features with Proteus LPSs. 相似文献
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Nina A. Kocharova Evgeny Vinogradov Alexander S. Shashkov Antoni Rozalski Yuriy A. Knirel 《Journal of carbohydrate chemistry》2013,32(5):320-331
An oligosaccharide isolated from the lipopolysaccharide of Providencia alcalifaciens O19 was found to consist of a single O‐antigen repeating unit linked to the core. The full oligosaccharide structure was elucidated by 2D 1H, 13C, and 31P NMR spectroscopy. It was shown that the inner core region has the same structure as in other Providencia strains studied, whereas the outer core is structurally diverse between Providencia strains. A pyruvic acid acetal was found in the isolated oligosaccharide and in the long‐chain O‐antigen, whose structure has been established earlier. The biological O‐unit structure was elucidated in the short‐chain lipopolysaccharide. 相似文献
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