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991.
992.
Fulin Chen Naihuan Jing Fei Kong Shaobin Tan 《Journal of Pure and Applied Algebra》2022,226(1):106814
In this paper we introduce a new quantum algebra which specializes to the 2-toroidal Lie algebra of type . We prove that this quantum toroidal algebra has a natural triangular decomposition, a (topological) Hopf algebra structure and a vertex operator realization. 相似文献
993.
994.
在同系物方法测定胶束迁移速度(l/tm c ) 的基础上提出了一种同时求算电渗流速率(l/t0) 的t0 和tm c 的新方法, 该法在选择同系物标记物较为适当时, 可以得到更为准确的结果。同时可以减少由t0 测定而带来的误差。 实验结果表明, 采用甲醇等标记物测定电渗流速率时, 由于其在胶束中的溶解使得实测结果较真值偏大,而由此计算得到的tm c 值偏低。t0 、tm c 皆与缓冲液的种类和浓度有关, 这可能是由于缓冲液组成的变化不仅使得离子强度改变, 也使柱管壁和胶束表面的ξ势发生变化所致。同系物标记物的选择对t0 、tmc 测定精度影响的讨论也为实际分析系统t0 、tmc 的测定和分析分离条件的优化选择提供了必要的理论依据。 相似文献
995.
996.
Kai Yao Yiwang Chen Lie Chen Huanling Kong Weihua Zhou Fan Li Xiaohui He Yen Wei 《Journal of polymer science. Part A, Polymer chemistry》2010,48(2):434-442
Novel liquid‐crystalline alternating conjugated copolymers [ P(P(6)CN‐alt‐Cz) and P(P(6)CN‐alt‐MeP) ] with phenylene and carbazolylene or phenylene with methyl substitution onto the main chain have been synthesized through palladium‐catalyzed Suzuki coupling reactions. The influence of the incorporation of carbazolylene and the substituted phenylene into the main chain on the thermal, mesomorphic, and luminescent properties has been investigated by Fourier transform infrared spectroscopy, thermogravimetry, differential scanning calorimetry, polarized optical microscopy, ultraviolet–visible spectroscopy, photoluminescence (PL), and cyclic voltammetry. These polymers show highly thermal stability, losing little of their weights when heated to 360 °C. The conjugated copolymers exhibit liquid crystallinity at elevated temperature. The existence of the chromophoric terphenyl core endows the copolymers with high PL and the polymer P(P(6)CN‐alt‐Cz containing carbazolylene unit can emit more pure blue light. All the copolymer films with low band gaps about 2.3–2.4 eV undergo reversible oxidation and reduction processes, significantly lower than the band gap of poly(p‐phenylene). © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 434–442, 2010 相似文献
997.
Based on the analysis and the discussion of the influence of thermal ionization energy and various scatterings on magnetoresistance(MR) of p-type diamond films, a revised model of valence band split-off over temperature is put forward, and a corresponding calculation formula is given for the MR of p-type diamond films (Corbino discs). It is shown that the theoretical calculation that the MR of diamond films changes with temperature is consistent with the experiment. The influence of Fermi energy level on MR of diamond films is discussed. Additionally, the thermal effect mechanism of MR in p-type diamond films is also explored. 相似文献
998.
Yu Kong Ming‐Ming Yan Wei Liu Cai‐Yun Chen Bao‐Shan Zhao Yuan‐Gang Zu Yu‐Jie Fu Meng Luo Michael Wink 《Journal of separation science》2010,33(15):2278-2286
The enrichment and separation of astragalosides I–IV (AGs I–IV) were studied on eight macroporous resins in the present study. SA‐3 resin offered the best adsorption and desorption capacities for AGs I–IV than other resins. The models of adsorption kinetics were investigated in order to elucidate the mechanism of adsorption. The pseudo‐second‐order model was the better choice than the pseudo‐first‐order model to describe the adsorption behavior of AGs I–IV onto SA‐3 resin. The equilibrium experimental data were well fitted to Langmuir and Freundlich isotherms. SA‐3 resin adsorption chromatography tests were carried out to optimize the separation process of AGs I–IV from Radix Astragali extracts. With the optimum parameters for adsorption and desorption, the contents of AGs I–IV were 8.78‐, 11.60‐, 10.52‐ and 11.28‐fold increased with the recovery yields being 65.88, 90.92, 84.25 and 94.17%, respectively. The preparative enrichment and separation of AGs I–IV from Radix Astragali extracts can be easily and effectively achieved by SA‐3 resin adsorption chromatography. The developed methodology can also be referenced for the separation of other active constituents from herbal materials and manufacture of Radix Astragali products. 相似文献
999.
Chen Shifeng Wei Xuebin Liu Jinhui Sun Zhanxue Chen Gongxin Yang Mei Liu Yuanyuan Wang Duo Ma Chengcui Kong Dexuan 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(6):2583-2596
Journal of Radioanalytical and Nuclear Chemistry - Mineralogical study showed that the Yuejin uranium ore is from a low grade, high carbonate and high pyrite sandstone type uranium deposit. Uranium... 相似文献
1000.