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Search Results: 1 - 10 of 12274 matches for " XIA Zhining "
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Separation of enantiomers of three chiral drugs by capillary electrophoresis based on achiral ionic liquid
基于非手性离子液体的毛细管电泳法拆分3种手性药物

XIA Chen,CHEN Zhitao,XIA Zhining,
夏陈
,陈志涛,夏之宁

色谱 , 2008,
Abstract: 建立了以非手性离子液体1-正丁基-3-甲基咪唑氯(BMIM]Cl)为手性分离的添加剂、β-环糊精作为手性选择剂的毛细管区带电泳(CZE)分离扑尔敏、氯霉素前体和氧氟沙星3种对映体的方法,并与未添加BMIM]Cl的CZE分离情况进行了对比研究。发现BMIM]Cl对手性药物的拆分有协同作用,不仅能够增加对映体的分离度,还能有效地抑制毛细管内壁对样品分子的吸附作用,改善峰形。采用离子液体辅助手性选择剂(尤其是环糊精)的CZE改进方法,为其他毛细管电泳难以分离的手性药物的分离分析提供了新的方法。
Quantitative structure-gas chromatographic retention relationship of polycyclic aromatic sulfur heterocycles using molecular electronegativity-distance vector
多环芳香硫化合物的定量结构-气相色谱保留指数关系

LI Zhenghua,CHENG Fansheng,XIA Zhining,
李正华
,程凡圣,夏之宁

色谱 , 2011,
Abstract: The chemical structures of 114 polycyclic aromatic sulfur heterocycles (PASHs) have been studied by molecular electronegativity-distance vector (MEDV). The linear relationships between gas chromatographic retention index and the MEDV have been established by a multiple linear regression (MLR) model. The results of variable selection by stepwise multiple regression (SMR) and the powerful predictive abilities of the optimization model appraised by leave-one-out cross-validation showed that the optimization model with the correlation coefficient (R) of 0.9947 and the cross-validated correlation coefficient (RCV) of 0.9940 possessed the best statistical quality. Furthermore, when the 114 PASHs compounds were divided into calibration and test sets in the ratio of 2:1, the statistical analysis showed our models possesses almost equal statistical quality, the very similar regression coefficients and the good robustness. The quantitative structure-retention relationship (QSRR) model established may provide a convenient and powerful method for predicting the gas chromatographic retention of PASHs.
Evaluation of absorption of organic compounds in human body using liposome capillary electrophoresis
脂质体毛细管电泳方法评价有机化合物在体内的吸收

ZOU Xiaobing,JIANG Honggui,DONG Zhiqiang,XIA Zhining,JIANG Xuemei,
邹小兵
,蒋宏贵,董志强,夏之宁,蒋雪梅

色谱 , 2008,
Abstract: Liposome capillary electrophoresis (LCE) was used as a model for the in vitro evaluation of the degree of membrane penetration of organic compounds. The hydrophobic parameters of 9 compounds were determined by LCE. In comparison of the correlation coefficient of log Plw ( the logarithm of the partition coefficient of liposome/water system, calculated from retention factor) vs. log Pm (the logarithm of osmotic coefficient) with that of log Pow (the logarithm of the partition coefficient of octanol/water system) vs. log Pm, the former was 0.94, much greater than the latter 0.78. It means that as the biomembrane model, liposome is more similar than the octanol/water system. The LCE method has the potential to be an in vitro screening model.
Study on the Interaction of Ephedrine, Caffeine and Acetaminophen with Bovine Serum Albumin by Capillary Electrophoresis with Partial Filling Technique
区段灌注毛细管电泳研究药物与牛血清白蛋白的相互作用

GUO Baoyuan,XIA Zhining,CHEN Guohua,YIN Yongguang,XU Hongmei,
郭宝元
,夏之宁,陈国华,阴永光,徐红梅

色谱 , 2003,
Abstract: 以毛细管电泳为手段,采用毛细管区段灌注技术,对麻黄碱、咖啡因和扑热息痛3种药物与牛血清白蛋白(BSA)之间的相互作用进行了研究。将两个较短的药物区带分别置于一个较长的BSA区段前后,以区段前的药物为标记物,采用峰漂移模型,同时测得麻黄碱、咖啡因和扑热息痛与BSA的结合常数,其值分别为3 38×104L/mol,4 79×104L/mol和6 13×104L/mol。结果表明这种方法可作为药物与蛋白相互作用分析的一种改进方法,并且有效地避免了常规峰漂移模型和迎头分析法中采用非涂层毛细管时蛋白质在毛细管壁上的吸附和蛋白质背景吸收的干扰问题。
Chiral Separation of Citalopram Intermediate Compounds by CE
毛细管电泳手性分离分析西酞普兰中间体

JIANG Junpo,XU Hongmei,CHEN Zhitao,XIAO Shangyou,XIA Zhining,
姜军坡
,徐红梅,陈志涛,肖尚友,夏之宁

色谱 , 2006,
Abstract: 西酞普兰(citalopram,CIT)适用于抑郁性精神障碍的急性和常规治疗。S-( )-CIT对5-羟色胺有较好的抑制作用,R-(-)-CIT疗效较差1],故要求以S-( )-CIT单体形式上市。化合物(-)-4-4-(二甲氨基)-1-(4′-氟苯基)-1-羟丁基]-3-羟甲基-苯氰氢溴盐((-)-CITI)是S-( )-CIT合成中最重要的中间体,手性分离出(-)-CITI后通过环合即可制备S-( )-CIT单体。欲控制S-( )-CIT的光学纯度,必须先控制R-(-)-CITI的纯度。因此,建立(±)-CITI的手性分离方法及异构体的定量方法十分必要。本文在文献2]的基础上拆分了CITI对映体,定量测定了R-(-)…
Determination of dichlorvos in water by microwave-assisted headspace-liquid-phase microextraction coupled with high performance liquid chromatography
微波辅助-顶空液相微萃取在线联用-高效液相色谱法测定环境水样中的敌敌畏

KONG Na,ZOU Xiaobing,HUANG Rui,XIA Zhining,WEI Xinyang,
孔娜
,邹小兵,黄锐,夏之宁,魏欣旸

色谱 , 2010,
Abstract: A novel method for the determination of dichlorvos in environmental water samples has been developed using microwave-assisted-headspace-liquid-phase microextraction (MAE-HS-LPME) coupled with high performance liquid chromatography (HPLC). The influences of extraction parameters in the sample matrix were investigated. Under optimized experimental conditions, the detection limit (S/N=3), the quantification limit (S/N=10) and the enrichment factor of the proposed method for the target analyte were 0.96 μg/L, 3.20 μg/L and 54, respectively. The recoveries of target analyte spiked in real water samples were 87.4%~103%. The extraction performance of MAE-HS-LPME to the target analyte was also compared with liquid-liquid extraction (LLE). The results indicated that the developed method is simple, rapid, efficient, solvent-saving, highly selective and widely applicable.
A Functional Fingerprint of Traditional Chinese Medicine for Measuring the Oil-Water Partition Coefficients
具有油水分配系数测算功能的中药指纹图谱

YAN Lei,GONG Ping,YUAN Lin,JIANG Xuemei,XIA Zhining,
颜磊
,龚萍,袁林,蒋雪梅,夏之宁

色谱 , 2007,
Abstract: Following the principle and method on the measurement of oil-water partition coefficients by microemulsion electrokinetic chromatography (MEEKC), a traditional Chinese medicine fingerprint (TCM-FP) was established. The components which were extracted from the TCM were separated from each other by MEEKC under optimized operation conditions. The conditions of running solution were of 70 mmol/L SDS, 87 mmol/L n-heptane, 814 mmol/L n-butanol and 5 mmol/L sodium tetraborate with pH value of 8.80. The uncoated fused silica capillary used was 54 cm x 75 microm with an effective length of 45 cm. The UV detection was carried out at 210 nm and an electrophoretic voltage of 15 kV was applied. SPSS program was used for the nonlinear regression of migration time and log P(ow) values of the standard compounds from literature, and the reliability of the established method has been investigated. As a result, the standard equation of regression with good linearity (r = 0.988 0) was obtained. The log P(ow) values of compounds measured under the same operation conditions were well consistent with those from literature. This method was applied to L. lucidum in which oleanolic acid is a main effective component. Besides the establishment of its TCM-FP, the log P(ow) of oleanolic acid, 3.63, was also obtained. The functional fingerprint of traditional Chinese medicine can give the log P(ow) of the extracts from TCM, reflect oil-water partition character of the constituents, and is of great significance to the selection of solvents, the design of dosage form, and the improvement of production technology.
Separation of Phthalates in Non-Aqueous Micelle Using Capillary Electrokinetic Chromatography
非水胶束电动色谱分离邻苯二甲酸酯类化合物

HUANG Rui,MU Xiaojing,YIN Yongguang,WEI Weili,CHEN Zhitao,XIA Zhining,
黄 锐
,穆小静,阴永光,魏为力,陈志涛,夏之宁

色谱 , 2006,
Abstract: On the basis of non-aqueous capillary electrophoresis(NACE) and micellar electrokinetic chromatography(MEKC),a novel technique,non-aqueous micellar electrokinetic chromatography(NAMEKC),has been established.NAMEKC has the advantages of NACE and(uses) the separation mechanism of MEKC,showing special advantages for separation of hydrophobic compounds.Separation of three of the priority pollutants by U.S.Environmental Protection Agency(EPA),i.e.dimethyl phthalate(DMP),diethyl phthalate(DEP),and dibutyl phthalate(DBP),were realized in 15 min.Important factors on separation,such as the(amount) of water added in the electrophoretic running buffer,the acidity of water phase,the(organic) additive,and the concentration of sodium dodecyl sulfate(SDS),were investigated.The proportion of water in the electrophoretic running buffer could affect the current and the stability of SDS micelle.Organic additives and the acidity of water phase showed no effect on increasing resolution.The concentration of SDS was a dominant factor,affecting the partition of analytes in micelle.DMP, DEP,and DBP were separated in a short time under the optimized operation conditions using 20 mmol/L NaH_2PO_4 and 120 mmol/L SDS in formamide/water(9/1,v/v).The application of NAMEKC leads to successful separation of the three typical hydrophobic compounds,which provides a novel means to separate and analyze hydrophobic compounds.
Renormalisability of the SU(n) Gauge Theory with Massive Gauge Bosons
Ze-sen Yang,Zhining Zhou,Yushu Zhong,Xianhui Li
Physics , 1999,
Abstract: The problem of renormalisability of the SU(n) theory with massive gauge bosons is reinverstigated in the present work. We expound that the quantization under the Lorentz condition caused by the mass term of the gauge fields leads to a ghost action which is the same as that of the usual SU(n) Yang-Mills theory in the Landau gauge. Furthermore, we clarify that the mass term of the gauge fields cause no additional complexity to the Slavnov-Taylor identity of the generating functional for the regular vertex functions and does not change the equations satisfied by the divergent part of this generating functional. Finally, we prove that the renormalisability of the theory can be deduced from the renormalisability of the Yang-Mills theory.
Scattering Matrix of the SU(n) Gauge Theory with Explicit Gauge Mass Term
Yang Ze-sen,Li Xianhui,Zhou Zhining,Zhong Yushu
Physics , 1999,
Abstract: Based on the renormalisability of the SU(n) theory with massive gauge bosons, we start with the path integral of the generating functional for the renormalized Green functions and develop a method to construct the scattering matrix so that the unitarity is evident. By using as basical variables the renormalized field functions and defining the unperturbed Hamiltonian operator $H_0$ that, under the Lorentz condition, describes the free particles of the initial and final states in scattering processes, we form an operator description with which the renormalized Green functions can be expressed as the vacuum expectations of the time ordered products of the Heisenberg operators of the renormalized field functions, that satisfy the usual equal time commutation or anticommutation rules. From such an operator description we find a total Hamiltonian $\widetilde{H}$ that determine the time evolution of the Heisenberg operators of the renormalized field functions. The scattering matrix is nothing but the matrix of the operator $U(\infty, -\infty)$, which describes the time evolution from $-\infty$ to $\infty$ in the interaction picture specified by $\widetilde{H}$ and $H_0$, respect to a base formed by the physical eigen states of $H_0$. We also explain the asymptotic field viewpoint of constructing the scattering matrix within our operator description. Moreover, we find a formular to express the scattering matrix elements in terms of the truncated renormalized Green functions.
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