毛细管色谱法测定头孢美唑中的有机溶剂残留量

采用毛细管气相色谱法，以叔丁基甲醚为内标，用Agilent DB-200毛细管气相色谱柱和氢焰离子化检测器．同时测定了头孢美唑中甲醇、乙醇、二氯甲烷、三乙胺、乙酸乙酯、苯甲醚等6种有机溶剂残留量．6种溶剂的线性范围分别为0～480μg／mL（r=0．9996）、0—800μg／mL（r=0．9994）、0～96μg／mL（r=0．9990）、0～800μg/mL（r=0．9993）、0～800μg／mL（r=0．9995）、0～800μg／mL（r=0．9993）；平均回收率分别为100．1％、100．5％、101．2％、100．1％、100．7％和100．4％；相对标准偏差分别为0．90％、1．30％、1．18％、1．23％、1．52％、1．41％（n=9）．     

高效液相色谱法测定猪肉中土霉素、四环素残留量

建立了高效液相色谱法测定猪肉中四环素族抗生素留量的方法。通过对样品前处理方法进行优化,用高效液相色谱法测定了猪肉中土霉素、四环素2种四环素族抗生素的残留量。该法对土霉素、四环素检出限分别为1μg/L、1.88μg/L,相对标准偏差为3.2%~3.3%,平均回收率为82~86。     

高效液相色谱法测定白菜中农药马拉硫磷残留量

采用高效液相色谱法测定了白菜中农药马拉硫磷残留量．研究结果显示：在10．0-50．0μg/mL浓度范围内峰面积与进样量具有良好的线性关系，相关系数r=O．9996；相对标准偏差RSD为0．21％（以峰面积计算）和0．84％（以浓度计算）；平均加标回收率在85．6％-106．0％之间；最低检出限LDD=2．0μg/L.     

用柱后衍生荧光测定法检测食品中土霉素和四环素残留

应用高效液相色谱(HPLC)对动物性食品中土霉素(OTC)和四环素(TC)进行测定，样品经含乙二胺四乙酸二钠的丁二酸钠缓冲液除蛋白后，由SPE-C18小柱提纯净化，经ODS-C18柱分离后，用8％氧氯化锆溶液柱后衍生，与锆离子的螯合物在激发波长(Ex)：406nm和发射波长(Em)：515nm处检测。实验优化了锆试剂的浓度和柱后衍生的条件，提高了栓出的灵敏度，土霉素和四环素的回收率分别为89．59％和92．59％，变异系数(CV)分别为4．98％和6．74％。土霉素和四环素的最低栓出浓度(信噪比5：1)分别为3μg/L和5μg/L，线性范围为0．01～10μg/L，土霉素和四环素的相关系数分别为0．9999和1．0000。     

分光光度法测定矿石中痕量铅

用双硫腙显色分光光度法测定铁矿石中痕量铅，该方法具有简单、快速、灵敏等特点，用以测定铁矿石中的痕量铅，获得了满意的结果．检出限为0．06μg／mL，线陛范围为0．01μg／mL～1．0μg／mLPb^2＋，相关系数为0．9996，回收率89％～99％．     

酸性高锰酸钾化学发光体系测定针剂中的头孢噻肟钠

头孢噻肟钠碱性水解产物与高锰酸钾反应可产生微弱的化学发光，多聚磷酸对其有强烈的增敏作用，据此建立了一种简单、快捷、灵敏的流动注射化学发光测定头孢噻肟钠的新方法．化学发光信号ICL与头孢噻肟钠质量浓度C在0．02-20μg／mL和20～120μg／mL范围内呈良好的线性关系，回归方程分别表示为ICL=3.169＋20．961C（r=0．9998，n=9）；ICL=147．5＋14．752C（r=0．9994，n=9），方法的检出限为20ng／mL．对5μg／mL头孢噻肟钠进行11次平行测定，相对标准偏差为0．8％，用本法对针剂中头孢噻肟钠的含量进行了测定，得出了令人满意的结果．     

Ir(Ⅳ)-二甲基黄-高碘酸钾体系催化光度法测定痕量铱

在稀磷酸介质中，铱催化高碘酸钾氧化二甲基黄褪色，据此建立了测定痕量铱的新催化光度法。方法的线性范围为0．032～0．088μg／mL，检出限为7．54×10^-7μg／mL，对1．0μg／25mL Ir（Ⅳ）测定的相对标准偏差为1．5％（n=11）。这种方法简单、灵敏，已用于冶金产品中铱的测定，结果较好。     

微量进样-火焰原子吸收分光光度法测定红细胞以及其它组织中的铅

在国产GGX-600型原子吸收分光光度计上采用微量进样技术,用火焰原子吸收光谱法测定了小白鼠红细胞、血清、肝、肾、脾、肺、心脏和大脑中铅的含量。实验结果表明该方法铅在0．050～1．000μg／mL呈良好线性关系,r=0．9997,方法平均回收率97．4％,RSD=4．2％,特征浓度为0．0916μg/mL,检出限为0．0500μg／mL。方法操作简单,重现性好,结果准确且待测样品用量少。     

HPLC法测定奶粉中痕量炔雌醇

建立了高效液相色谱（HPLC）法测定奶粉中炔雌醇残留量的方法。样品以乙腈振荡萃取、离心,提取液浓缩后经O．45μm滤膜过滤,冷冻去脂,进高效液相色谱仪分析。研究了萃取溶剂、萃取及浓缩方式对萃取效率的影响,确立了色谱检测条件。乙腈-水（50：50）为流动相,流速1mL／min,柱温30℃,检测波长224nm。方法的检出限为16μg／kg,加标回收率在86．5％～97．0％之间,工作曲线的相关系数为0．9990,相对标准偏差为0．95％～2．01％（n=3）。方法快速、灵敏度高、分离效果好,样品处理简单、无杂质干扰,能够满足奶粉中雌激素分析的需要。     

邻菲罗啉-OP分光光度法测定高纯硅中微量铁

研究了用邻菲罗啉-OP乳化剂分光光度法测定高纯硅微粉中微量铁的方法．测铁的线性范围为0-100μg／25mL．检出限为0．020μg／mL．该法显色灵敏，选择性好，用于高纯硅样品中微量铁的测定，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     

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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Brief Introduction to “Journal of Jilin University( Science Edition) ”

<正>"Journal of Jilin University(Science Edition)"is a comprehensive academic journal in the fields of science sponsored by Jilin University and administrated by the Ministry of Education of the Peoples Republic of China.The journal started publication in 1955.The original name at starting publication was"Journal of Natural Science of Northeast People University",which was changed into"Acta Scientiarum Naturalium Universitatis Jilinensis"in 1958 owing to the name change of the university.The present journal name has