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Kong De-Zhi Yuan Zhi-Fang Zhang Xiao-Wei Sheng Xiao-Na Wang Na Xing Song-song Du Yu-Min Zhang Lan-Tong 《Chromatographia》2009,70(11):1743-1748
A rapid and simple method has been developed and validated for the determination of m-nisoldipine and its five related substances using micellar electrokinetic capillary chromatography (MEKC). The key factors, including pH, buffer concentration and buffer additive, sodium dodecyl sulfate (SDS) concentration, applied voltage and temperature were systematically investigated in an uncoated fused silica capillary. The total analysis time was less than 9 min. The forced degradation products of m-nisoldipine, which were induced by hydrogen peroxide, acidic and basic conditions, heat and light, were also tested.
相似文献13.
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Jian Zhang Tian-Qi Zhao Yao Chen Xiao-Dong Chen Hai-Kun Chang Yu-Min Zhang Shu-Cheng Hua 《Chemical Papers》2015,69(2):325-338
A solvent-free microwave-assisted method for the synthesis of 2-substituted-4,5-di(2-furyl)-1H-imidazoles was developed. Imidazoles with moderate to good yields were produced by condensation of furil with aldehydes over acidic alumina impregnated with ammonium acetate, and they were characterized by FT-IR, HRMS, 1H NMR and 13C NMR spectroscopy. Crystal structure of 2,4,5-tri-2-furyl-1H-imidazole (I) in the orthorhombic space group Pbca was reported, which showed more coplanarity than the reported crystal structure of I in the monoclinic space group Cc. Moreover, their luminescent properties were investigated. It was found that the organic small molecule compounds synthesized possess higher fluorescence quantum efficiency (up to 0.508) in a 0.1 M H2SO4 aqueous solution dissolved in 0.5 mL of CH3OH; along with higher stability; also the emission of some compounds synthesized in the solution was sensitive to the polarity of the solvents. 相似文献
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Thermophysical properties of pure 1-ethyl-3-methylimidazolium methylsulphate and its binary mixtures with alcohols 总被引:1,自引:0,他引:1
Jian-Ying WangFeng-Yun Zhao Yu-Min LiuXiao-Ling Wang Yong-Qi Hu 《Fluid Phase Equilibria》2011,305(2):114-120
The density and surface tension of 1-ethyl-3-methylimidazolium methylsulphate, [EMIM][CH3SO4] ionic liquid have been measured from (283.15 to 333.15) K. The coefficient of thermal expansion was calculated from the experimental density results using an empirical correlation for T = (283.15-338.15) K. Molecular volume and standard entropies of [EMIM][CH3SO4] ionic liquid were obtained from the experimental density values. The surface properties, critical temperature and enthalpy of vaporization were also discussed. Density and surface tension have been measured over the whole composition range for [EMIM][CH3SO4] with alcohols (methanol, ethanol, 1-butanol) binary systems at 298.15 K and atmospheric pressure. Excess molar volumes and surface tension deviations for the binary systems have been calculated and were fitted to a Redlich-Kister equation to determine the fitting parameters and the root mean square deviations. 相似文献
17.
Luminol-Cu(Ⅱ)体系流动注射化学发光法测定乙酰半胱氨酸 总被引:1,自引:0,他引:1
发现了Luminol-Cu(Ⅱ)-乙酰半胱氨酸化学发光体系,探讨了影响化学发光反应的各个因素,建立了测定乙酰半胱氨酸的流动注射化学发光新方法。该方法的线性范围为7.0×10-10—1.0×10-7g/mL,检出限为2.0×10-11g/mL,相对标准偏差为1.0%(1.0×10-8g/mL,n=11)。该方法已用于药物制剂中乙酰半胱氨酸含量的测定。 相似文献
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This paper theoretically investigates three stochastic systems with cross-correlation Gaussian white noises.Both steady state properties of the stochastic nonlinear systems and the nonequilibrium transitions induced by the cross-correlated noises are studied.The stationary solutions of the Fokker-Planck equation for three specific examples are analysed.It is shown explicitly that the cross-correlation of white noises can induce nonequilibrium transitions. 相似文献
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在重构核粒子法的基础上,引入复变量,讨论了复变量重构核粒子法.复变量重构核粒子法的优点是在构造形函数时采用一维基函数建立二维问题的修正函数.然后,将复变量重构核粒子法应用于瞬态热传导问题的求解,结合瞬态热传导问题的Galerkin积分弱形式,采用罚函数法引入本质边界条件,建立了瞬态热传导问题的复变量重构核粒子法,推导了相应的计算公式.与传统的重构核粒子法相比,复变量重构核粒子法具有计算量小、精度高的优点.最后通过数值算例证明了该方法的有效性.
关键词:
重构核粒子法
复变量重构核粒子法
修正函数
瞬态热传导问题 相似文献