毛细管电泳-安培法测定酵母菌中的RNA

报道了通过毛细管电泳-安培检测法测定腺嘌呤(A)和鸟嘌呤(G)来间接测定酵母菌中核糖核酸含量的方法.探讨了电极电位、运行缓冲溶液、分离电压及进样时间等对毛细管电泳分离-安培检测的影响,得到了较为优化的测定条件.在30 mmol/L 的硼酸盐缓冲液(pH 9.0)中,上述两组分可在18 min 内完全分离.腺嘌呤和鸟嘌呤的检测限分别为2.0×10^-7mol/L和1.7×10^-7 mol/L.该法具有较好的重现性和灵敏度,可以用于食品中酵母菌中核糖核酸的快速测定.     

毛细管区带电泳法测定白藜芦醇与白藜芦醇苷

建立了以苄基三甲基碘化铵为内标测定白藜芦醇和白藜芦醇苷的毛细管区带电泳方法,在优化的分离条件下,两者在7 min内可基线分离,检出限均为1.25×10-4g/L,线性动态范围分别是4.88×10-4g/L~0.31 g/L和5.37×10-4g/L~0.34 g/L,样品的加标回收率为95.44%和97.75%.     

槐米中芦丁和槲皮素的毛细管电泳-电化学检测

用毛细管区带电泳 -电化学检测法测定了中药槐米中芦丁和槲皮素的含量。研究了电极电位、电解液酸度和浓度、电泳电压及进样时间等对电泳的影响 ,得到了较为优化的测定条件。以直径为 30 0 μm的碳圆盘电极为检测电极 ,电极电位为 0 .90V (vs .SCE) ,在 10 0mmol/L硼酸盐缓冲液 (pH 9.0 )中 ,上述两组分在 10min内完全分离。芦丁和槲皮素浓度与电泳峰电流分别在 7.5× 10 - 7～ 1.0× 10 - 3和 5 .0× 10 - 7～ 1.0× 10 - 3mol/L范围内呈良好线性 ,检测下限分别为 4 .34× 10 - 7和 2 .2 5× 10 - 6 mol/L。 7次测定含 5 .0× 10 - 4 mol/L芦丁和槲皮素的试样溶液 ,峰高的相对标准偏差分别为 2 .5 6 %和 4 .11% ,五次测得的平均回收率分别为 97.80 %和 96 .84 %     

高效毛细管电泳法测定牛奶和奶糖中的三聚氰胺

目的 研究建立一种高效毛细管电泳分离测定痕量三聚氰胺的新方法.方法 以高度压差进样,在优化的实验条件下,采用高效毛细管电泳对三聚氰胺进行分离检测.结果 三聚氰胺的峰面积与其质量浓度在1～100μg/mL范围内呈良好的线性关系,相关系数为0.999 04,检出限为0.27μg/mL(S/N=3).应用于牛奶和奶糖中三聚氰胺含量的测定,回收率为81.36%～93.52%,相对标准偏差为2.82%～5.89%.结论 该法可用于食品及饲料中三聚氰胺含量的测定.     

毛细管电泳电化学检测葛根和葛藤中几种黄酮类化合物

用毛细管电泳电化学检测法测定了葛根和葛藤中葛根素、大豆甙元和芦丁含量.以碳圆盘电极为检测电极,电极电位为0.90V(vs.SCE),在50mmol/L硼酸盐缓冲液(pH9.0)中,使用长40cm熔融石英毛细管,当分离电压为9kV,上述三组分在12min内完全分离.葛根素、大豆甙元和芦丁浓度与电泳峰电流分别在2.5×10-6～1.0×10-3,1.0×10-6～1.0×10-3和5.0×10-6～1.0×10-3mol/L范围内呈良好线性,检出限(S/N=3)分别为3.4×10-7,2.4×10-7和5.1×10-7mol/L.7次测定葛根素、大豆甙元和芦丁的混合标准溶液,峰高的相对标准偏差分别为2.71%,2.47%和4.21%.     

组培甜菊糖苷的变化研究

研究了甜菊组培过程中,甜菊苷（Stevioside,缩写为SS）和丽鲍迪苷A（Rebaudioside,缩写为 RA）两种主要甜味成份的变化以及不同浓度的6-卞氨基腺苷(6-BAP)对愈伤组织合成SS及RA的影响,并初步探讨了根部在糖苷合成过程中的作用.结果表明甜菊愈伤组织合成糖苷的能力随培养时间的不同而异.培养10 d的愈伤组织可检测到少量残余叶片的SS及RA,而培养20 d,30 d的愈伤组织则未检出.培养40 d的愈伤组织仅检测到RA,表明此时的愈伤组织又恢复了合成糖苷的能力,推测与叶绿体的再分化有关.在含有不同浓度6-BAP的培养基中培养2个月的愈伤组织都能够合成糖苷,但所合成糖苷的组分不同.其中,在含有0.5 mg/L,1 mg/L,2 mg/L 6-BAP 培养基中的愈伤组织只能积累RA,且随浓度的增加, RA的含量逐渐降低;而含有3 mg/L 6-BAP培养基中的愈伤组织只能合成SS.有根苗可合成SS及RA.而无根腋芽苗只能合成SS.     

毛细管区带电泳-电化学法检测洋葱中活性成分

采用毛细管区带电泳-电化学检测法(CE-ED)同时测定了洋葱中芥子酸、槲皮素和原儿茶酸的含量,研究了电极电位、运行液浓度和分离电压等实验参数对分离检测的影响.在优化的条件下,以直径300 μm的碳圆盘电极为工作电极,电极电位为＋950 mV(vs.SCE), 在pH 9.0的40 mmol/L的硼酸运行缓冲液中,上述3组分在25 min内可完全分离.芥子酸、槲皮素和原儿茶酸的浓度分别在2.0×10^-7-1.0×10^-4g/mL、2.0×10^-7-5.0×10^-5g/mL和5.0×10 ^-7-5.0×10^-5g/mL的范围内与峰电流呈良好线性关系,检测下限分别为1.5×10^-7g/mL、1.6×10^-7g/mL和3.6×10^-7g/mL,7次测得的三种组分峰高的相对标准偏差分别为2.70%、4.65%和1.73%,三次测得的平均回收率分别为102.2%、105.5%和100.9% .     

高效毛细管电泳分离检测5种喹诺酮类抗生素

采用高效毛细管电泳分离检测加替沙星、洛美沙星、依诺沙星、环丙沙星和氧氟沙星等5种喹诺酮类抗生素,探讨了电泳参数对分离结果的影响.在检测波长为268 nm时,确定最佳实验条件为:电泳缓冲液为pH值为8.8的15 mmol/L Na2B4O7-15 mmol/L KH2PO4溶液,分离电压为8 kV,高差为10 cm,进样时间为20 s.在最佳分离条件下,5种抗生素在9 min内实现基线分离,样品浓度在2×10-6～4×10-6 mmol/L之间.同时,在最佳分离条件下检测市售洛美沙星片中洛美沙星的质量分数为36%,回收率为109.4%.     

毛细管电泳有效分离和同时检测8种氟喹诺酮

对快速分离和同时测定人体尿液中8种氟喹诺酮的毛细管区带电泳新方法进行了研究.采用高效毛细管电泳进行分离;以4×10-2 mol/L硼砂和0.1 mol/L磷酸作电泳缓冲溶液(pH=9.15);5 kPa压力和25℃条件下进样4 s,在22 kV电压下进行毛细管电泳分离,以紫外检测器于278 nm波长下检测.8种氟喹诺酮的校准曲线呈良好的线性关系(r0.999 5),回收率为81.82%～104.24%;检出限为1.05～2.08 mg/L,相对标准偏差小于4%.所提出的方法能有效分离和同时测定人体尿液中的多种喹诺酮.     

肉制品中β-兴奋剂的毛细管电泳-电化学检测方法

首次采用毛细管电泳-电化学检测法（CE-ED）同时测定了肉制品中β-兴奋剂盐酸克伦特罗与沙丁胺醇的含量,考察了缓冲液酸度和浓度、分离电压、氧化电位和进样时间等实验参数对分离检测的影响.在最佳实验条件下,工作电极为直径300 μm的碳圆盘电极,检测电位为+950 mV（vs. SCE）,缓冲液为40 mmol/L硼砂溶液（pH =7.4）,分离电压 18 kV,上述组分在8 min中内即可实现分离.盐酸克伦特罗和沙丁胺醇在两个数量级的范围内呈良好线性关系,检测下限（S/N=3）分别为1.11×10-7和9.80×10-8 mol/L,且抗坏血酸对其检测不产生干扰.该方法已成功地应用于实际样品中β-兴奋剂残留状况的分析,结果令人满意.     

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     

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     

Journal of Donghua University ( English Edition) Contents of Volume 31

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