HPLC法测定二益丸中阿魏酸和欧前胡素的含量

建立同时测定二益丸中阿魏酸和欧前胡素含量的方法。采用高效液相色谱(HPLC)法。色谱柱:资生堂C18(5μm,250×4.60mm);流动相:甲醇(A)-0.4%冰醋酸溶液(B),梯度洗脱;流速:1.0mL·min-1;紫外检测波长:313nm。阿魏酸和欧前胡素分别在质量浓度为4.19～209.5mg·mL-1、6.08～243.4mg·mL-1内与峰面积呈良好的线性关系(r均≥0.999);精密度分别为1.1%和1.7%(n=6);在24h内二益丸供试品溶液稳定性良好;重复性分别为1.3%和0.6%(n=6);平均加样回收率分别为93.71%和96.96%,RSD为1.22%和0.96%(n=6)。本研究所述方法适用于二益丸中当归和白芷的质量控制。     

N-苯甲酰基-O-苯甲酰基-L-酪氨酸及其对映异构体的手性高效液相色谱分析

建立了正相高效液相色谱法(NP-HPLC)测定中间体N-苯甲酰基-O-苯甲酰基-L-酪氨酸(L042)及其对映异构体N-苯甲酰基-O-苯甲酰基-D-酪氨酸(D042)含量的方法.采用CHIRALPAK AD-H手性柱,以环己烷-无水乙醇-三氟乙酸(50∶50∶0.2)为流动相,流速0.5mL·min-1,检测波长231nm,L042与其对映异构体获得良好的分离效果.在此条件下,L042、D042分别在浓度5.25~104.04μg·mL-1(n=6),2.15~107.44μg·mL-1(n=7)范围内与峰面积呈良好的线性关系,相关系数均达到0.999 9;平均回收率分别为99.69%(RSD 1.31%)和101.12%(RSD 1.91%);检出限分别为0.93和0.44μg·mL-1.建立了外标法测定L042含量的方法,对比了外标法及主成分自身对照法测定对映异构体D042的含量,选择节约检测成本的主成分自身对照法测定批量生产样品中的D042.该法准确、简便,适用于该中间体光学纯度的检测.     

鸦胆子油中β-谷甾醇的分离与含量测定

采用溶剂提取和两次硅胶柱层析法分离鸦胆子油中的β-谷甾醇,并用波谱学方法进行鉴定;对鸦胆子油用氢氧化钾-乙醇皂化后,采用气相色谱法对β-谷甾醇的含量进行测定.色谱条件为:Agilent HP-5毛细管柱(30m×250μm×0.25μm);FID检测器;进样口温度为285℃;程序升温:270℃(24 min),10℃·min-1升温至280℃(15 min);检测器温度为300℃;分流比为40∶1;流速为1 m L·min-1;进样量为1μL.β-谷甾醇对照品的峰面积与质量浓度在0.028 47~0.410 0 mg·m L-1呈良好的线性关系(r=0.999 4).该方法的平均回收率为95.2%(RSD=2.98%),测得8份样品中β-谷甾醇的质量分数在2.96~4.37 mg·g-1.本方法快速、简便、重复性好,可用于鸦胆子油中β-谷甾醇的含量测定.     

培氟沙星的气相色谱法测定及其应用

采用三氟化硼-甲醇为衍生化试剂,以HP-FFAP毛细管柱为分离柱,建立了培氟沙星的气相色谱分析法.培氟沙星在质量浓度1.0 mg/L～250.0 mg/L内,药物与内标物峰面积比和药物浓度呈良好的线性关系,检出限为10 μg/L.该方法前处理步骤简单,处理后杂质干扰少,灵敏度高,适用性强,用于药物制剂和体液中培氟沙星含量的测定,平均回收率为93.75%～102.73%,日间RSD均小于2.85%(n=5).     

西咪替丁的线性扫描极谱法测定

用线性扫描极谱法研究了西咪替丁的电化学行为.在0.16 mol·L-1Na2HPO4-KH2PO4缓冲溶液(pH6.65)中,西咪替丁于-1.903V(vs.SCE)处产生一灵敏的吸附波,其一次线性扫描极谱峰电流与西咪替丁浓度在4.0 mg·L-1-200.0 mg·L-1范围内呈良好的线性关系,相关系数r=0.9935(n=10),检出限为2.0 mg·L-1.对80.0 mg·L-1西咪替丁溶液进行6次平行试验,RSD为0.86%,回收率在94.7%-99.4%之间.本方法操作简便、准确、结果重现性好,可用于胶囊中西咪替丁含量的测定.     

正丙醇-溴化钾-氯化钠体系萃取分离金(III)

研究了氯化钠存在下,氯化钠-溴化钾-正丙醇体系萃取分离Au(III)的行为,实验表明,Au(III)与B r-形成的[AuB r4-]很容易被萃取到正丙醇相中,当溶液中氯化钠、溴化钾和正丙醇的浓度分别为0.20 g.mL-1、0.20 mg.mL-1、0.30mL.mL-1,pH=2.5时,能使Au(III)定量萃取.V(Ⅴ)、Ga(III)、N i(II)、A l(III)、Zn(II)、U(IV)等离子基本不被萃取,实现了Au(III)与上述离子的分离.     

HPLC法同时测定阿司匹林片中阿司匹林与杂质水杨酸含量

建立一HPLC法用于测定阿司匹林片中阿司匹林和杂质水杨酸的含量.以C18柱为固定相,以乙腈-甲醇-0.01 mol/L磷酸二氢钾溶液-三乙胺溶液(5∶48∶47∶0.1,用磷酸调pH值至3.3~3.4)为流动相,流速1.0mL/min,检测波长280 nm,在这一色谱条件下,阿司匹林和水杨酸分离良好;阿司匹林在0.183~0.427 mg/mL内,线性关系良好,r=0.9997,平均回收率为99.81%,RSD为0.24%(n=6);水杨酸在1~12μg/mL内,线性关系良好,r=0.9999,平均回收率为101.09%,RSD为0.77%(n=6).本法简单、灵敏、准确、精密,可作为阿司匹林片的质量控制方法.     

高效液相色谱法测定左西孟旦血药浓度

目的采用HPLC法测定beagle犬血浆中的左西孟旦浓度。方法色谱柱为Hypersil ODS C18柱(4.6mm×250mm,5μm),流动相为乙腈-0.1%磷酸二氢钾溶液(体积比35︰65,pH3.0),柱温为常温,流速1.0mL/min,紫外检测器波长为286nm。结果左西孟旦血药浓度在25～5000ng.mL-1范围内,浓度与峰面积比有良好线性关系(r=0.9996),检测限为10ng.mL-1。平均方法回收率为(98.7±1.8)%(n=15),日内RSD≤3.0%,日间RSD≤6.4%。结论本方法简单、快速、准确,可用于左西孟旦犬体内的药动学研究。     

固相微萃取-气相色谱-串联质谱法测定蜂蜜中双甲脒及其代谢产物残留

建立了同时测定蜂蜜中的双甲脒及其代谢产物2,4-二甲基苯胺残留量的固相微萃取-气相色谱-串联质谱法。对固相微萃取的实验条件(萃取纤维、萃取时间、p H值等)进行了选择和优化,并建立了气相色谱-串联质谱(GC-MS/MS)的仪器检测方法。结果表明:在优化的实验条件下,双甲脒和2,4-二甲基苯胺的最低检出限分别为0.5μg/kg和3.0μg/kg;在0.01~1.0 mg/kg的浓度范围内,二者的添加回收率范围分别为81.9%~98.2%和75.5%~90.6%,相对标准偏差分别为5.0%~15.4%和7.9%~17.2%。该方法操作简便、灵敏度高、准确可靠,适用于蜂蜜中双甲脒及2,4-二甲基苯胺的检测。     

RP-HPLC法分离测定发酵液中的交沙霉素

采用RP-HPLC法测定发酵液中交沙霉素的含量.以C18为固定相;以甲醇-0.02 mol/L KH2PO4溶液(80∶20)为流动相,用1 mol/L的磷酸调节pH值为3,检测波长232 nm,在进样10μL、交沙霉素含量为31.25~800μg/mL范围内,交沙霉素峰面积与浓度呈良好的线性关系(r=0.9966),测试样品(n=6)RSD为0.45%,平均回收率为99.18%(n=6),RSD=0.49%.在该色谱条件下,采用RP-HPLC法能将交沙霉素与发酵液中的杂质组分实现良好分离.     

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