毛细管电泳-紫外检测益母草中的黄酮类化合物

用毛细管电泳-紫外检测法同时测定了4种黄酮类化合物(山奈酚、芦丁、金丝桃甙和槲皮素).研究了各种条件的影响,得到了优化的实验条件.采用无涂层毛细管在5 mmol/L的Na2B4O7-10 mmol/L的NaH2PO4缓冲溶液(pH=8.30)中,当检测波长为254 nm,分离电压为20 kV时,4种黄酮类化合物在6 m in内得到了良好的分离。山奈酚、芦丁、金丝桃甙和槲皮素的检测限分别为0.07、0.08、0.23和0.44μg/mL。该方法应用于益母草中黄酮类化合物的测定,结果基本满意。     

毛细管电泳法研究菊花、野菊及其复方药中的多元酚

运用毛细管电泳-电化学检测法测定菊花、野菊与复方药中的5种主要营养成分,所选体系对木犀草素和槲皮素有很好的分离效果。研究了电极电位、缓冲液浓度和酸度、电泳电压和进样时间等实验参数对分离、检测的影响,得到了较优化的实验条件。以碳圆盘检测电极为工作电极,直径300μm,检测电位为0．95V（vs．SCE）,在50mmol·L^-1硼砂-硼酸（pH=9．2）缓冲液中,研究组分在20min内完全分离。5标样检出限（S/N=3）在0．9×10^-6-2．5×10^-6g·mL^-1之间。     

毛细管电泳安培检测法同时测定厚朴酚与和厚朴酚

采用毛细管电泳安培检测法对厚朴酚及和厚朴酚的分离测定进行了详细研究.工作电极为0.3 mm碳圆盘电极,30 mmol/L、pH10.0的硼砂-氢氧化钠为运行缓冲液,分离电压21 kV,检测电位0.95 V.在最优化实验条件下,两待测物在6 min以内完全基线分离.厚朴酚及和厚朴酚的线性范围分别为0.2~50μg/mL和0.4~60μg/mL,检测限分别为0.06和0.2μg/mL.应用于中药厚朴以及中成药霍香正气水和保济丸中厚朴酚及和厚朴酚的检测.     

HPLC法测定仙桃草中芦丁、木犀草苷、木犀草素的含量

建立HPLC法同时测定仙桃草中芦丁、木犀草苷、木犀草素3种黄酮含量的方法.采用Venusil MP C18(2)色谱柱(4.6mm×250mm,5μm),以乙腈-0.2%磷酸溶液为流动相,梯度洗脱,流速1.0 mL/min,检测波长350nm,柱温为35℃.方法学验证结果表明,3种黄酮类化合物的分离度良好,且在各自质量浓度范围内线性关系良好,r≥0.999 1,平均加样回收率(n=6)在96.76%~98.03%,RSD为1.62%~1.93%.3种黄酮类化合物在不同批次仙桃草中的含量存在较大的差异,仙桃草中3种黄酮总量在373.458~673.413μg/g之间.由此表明,不同生产批次的仙桃草药材,其内在品质存在较大差异,本方法可用于仙桃草药材中多种黄酮类成分同步测定,同时可以为仙桃草的质量控制提供科学依据.     

高速逆流色谱分离纯化灯盏细辛中的黄酮类化合物

采用高速逆流色谱技术快速分离纯化灯盏细辛中的黄酮类化合物,以石油醚-乙酸乙酯-甲醇 水(4:6:3.5:6.5,V/V)为溶剂系统,转速850 r/min,流速2.0 mL/min,检测波长254 nm。从500 mg粗提物中分离得到4个黄酮类化合物：黄芩素 (87 mg)、木犀草素 (35 mg)、槲皮素 (46 mg)和芹菜素 (92 mg),经高效液相色谱法分析,其纯度分别为94.6%、92.5%、98.2%、97.5%。研究结果表明,应用高速逆流色谱分离灯盏细辛中的黄酮类化合物快速、高效且纯度高。     

毛细管电泳高频电导检测克林霉素的含量

建立了毛细管电泳高频电导法测定克林霉素含量的方法.考察了各种实验条件对分离和检测的影响.以2.4 mmol/L 甘氨酸 0.80mmol/L柠檬酸 4.0 mmol/L H3BO3(pH=6.5)为电泳介质,分离电压20.0 kV.在优化条件下,克林霉素的峰形良好,出峰时间快,线性范围为1.500～120.0μg/mL,检出限为0.5μg/mL.回收率达93.6%～98.9%.     

佛甲草细胞毒活性成分研究

采用半制备高效液相和中压柱色谱方法对佛甲草的化学成分进行纯化分离,并利用现代波谱技术鉴定单体化合物的结构,并采用MTT法对所得到的化合物进行细胞毒活性筛选.从佛甲草甲醇提取物中分离到9个纯化合物,分别鉴定为山奈酚(1)、木犀草素(2)、3,5,7,3',5'-五羟基黄酮(3)、槲皮素(4)、紫云英苷(5)、咖啡酸(6)、阿魏酸(7)、4-羟基苯甲酸(8)和β-谷甾醇(9).化合物1~8均为首次从该属植物中分得.体外细胞毒活性评价结果显示化合物1~7对Hep G2和Hep3B两个肝癌细胞株有不同程度的抑制作用.其中,苯丙酸类成分6~7比黄酮类成分1~5显示出强的细胞毒活性,IC50值范围为19.7~56.4μg/m L.     

亲和毛细管电泳法测定3种黄酮类化合物与人血清白蛋白的结合常数

采用亲和毛细管电泳技术, 对木犀草素、槲皮素和山柰酚3种黄酮类化合物与人血清白蛋白（HSA）的结合常数进行研究, 利用药物淌度变化和蛋白浓度的关系,计算得到木犀草素、槲皮素和山柰酚与HSA的结合常数分别为9.76×10⁵mol/L,1.24×10⁶mol/L和3.79×10⁵mol/L. 结果表明,此法可以作为研究药物与蛋白相互作用的一种简便可行方法.     

木犀草素在钯-石墨烯复合材料修饰电极上的电化学测定

用正己基吡啶六氟磷酸盐作为粘合剂制备了离子液体修饰碳糊电极(CILE),将钯-石墨烯(Pd-GR)复合材料修饰于CILE表面制得修饰电极(Pd-GR/CILE),并利用循环伏安法和示差脉冲伏安法(DPV)对木犀草素在该修饰电极上的电化学行为进行研究.结果表明在pH 1.5的磷酸盐缓冲溶液中木犀草素在该电极上循环伏安扫描得一对峰形良好的氧化还原峰,说明木犀草素的电化学反应得以实现.在优化条件下木犀草素的氧化峰电流与其浓度在1.0×10~(-9)~1.0×10~(-6)mol/L内存在线性关系,检测限为3.3×10~(-10)mol/L(3σ).利用本方法测定独一味胶囊中木犀草素的含量,回收率在95.6%~104.8%范围内,相对标准偏差(RSD)低于3.43%.     

木犀草素在直流加热单边热石墨柱电极上电化学行为及吸附溶出分析

单边热石墨柱电极(ss-HGCE)应用于重要黄酮类化合物木犀草素的吸附溶出分析.采用直流加热,与交流加热相比,装置简单方便便宜.吸附预富集阶段对电极加热,能有效地增强木犀草素方波伏安溶出峰电流.这是因为对电极加热引起的强制热对流,这种热对流能够增强传质,促进吸附,因此增强溶出响应.结果表明,预富集步骤对电极加热到58℃,检出限可达1.0×10-8 mol/L(S/N=3),比室温28℃时的1.3×10-7mol/L(S/N=3)降低了一个数量级,相应灵敏度也提高了.应用于模拟血清样品中木犀草素含量的测定,平均回收率是101.7%.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with