荷移光度法测定药片中的安乃近含量

用荷移光度法研究了氯冉酸与安乃近的荷移反应,确定了反应条件.氯冉酸与安乃近在乙醇介质中形成络合物,最大吸收波长为530nm,表观摩尔吸光系数为9.07×102L·mol-1·cm-1.安乃近浓度在0.02～0.20g·L-1时,符合比尔定律.该方法操作简单,重现性好,回收率和灵敏度高,相对标准偏差为1.3%,结果令人满意.     

荷移反应测定可可碱的研究及其应用

研究了可可碱与氯冉酸的荷移反应 ,确定了荷移反应的最佳条件 .在乙醇介质中 ,可可碱与氯冉酸在室温下可生成 1∶ 1的π-π型荷移络合物 ,其最大吸收波长为 31 8nm,表观摩尔吸光系数为 ε=1 .57× 1 0 5L·mol-1· cm-1 ,可可碱的浓度在 0 μg/ m L～ 1 .1 5μg/ m L 范围内与其吸光度呈线性关系 ,回收率为 98.3%～ 1 0 1 .1 % ,相对标准偏差为 0 .6%～ 1 .0 9%     

烟草化学成分AOTF一近红外在线模型转移研究

AOTF．近红外光谱仪采用全密封固化设计,没有任何可移动部件,不受温度、湿度、灰尘等外界环境的影响,其设计特点适合在线检测．建立的近红外光谱模型可以在多台近红外光谱仪之间转移,研究工作中采用直接矫正法来修正原模型光谱信息,提高信号的信噪比和复杂背景的校正,进行模型转移．转移后的烟草化学成分总糖、烟碱、氯在线检测模型的决定系数分别为0．9336、0．8961、0．9310．随机采集17个样品,用转移后的模型预测,总糖、烟碱、氯的平均相对标准偏差分别为3．19％、3．76％、5．00％,完全能够满足烟草工业在线检测需要．     

废次烟草中有效成分的综合利用

我国是烟草种植大国，由于地理环境、种植技术、气候等因素影响，每年均有一定数量的低等级烟草无法被收购，这些废烟草既不能烧又不能作为肥料，成为烟农的一种负担。此外，烟厂还有近三分之一的烟杆作为废料白白丢掉。其实这些废烟草中含有多种有利用价值的成分，如生物碱、布尼醇、糖类、酸等。其中烟碱、茄尼醇是烟草中很重要的有价值成分。烟碱（Nicotine）是一种生物碱，通常以柠檬酸、苹果酸结合成盐而存在于烟草中。烟碱在天然烟叶中的含量较高，一般可达12％－16％；在烟梗中的含量稍低一些，大约为5％－7％。因此，废次烟叶及其…     

萃取分光光度法快速测定烟草及制品中烟碱的研究

用酸为浸取剂,铬兰黑为显色剂,ＣＨ２Ｃｌ２ 萃取液,建立了快速简便、灵敏度高的测定烟草及制品中烟碱含量的萃取分光光度法．测量的线性范围为０～３３μｇ／ｍ ｌ．     

荷移反应分光光度法测定咖啡因

研究了咖啡因与氯冉酸之间的荷移反应 .测得络合物在乙醇介质中络合比为 1∶1 .在测定波长 31 9nm处 ,络合物的表观摩尔吸光系数为 1 .92× 1 0 4 L·mol- 1 ·cm- 1 ,咖啡因浓度在 0 .8mg/L～ 1 1 .0mg/L范围内符合比尔定律 ,平均加标回收率为 95 .2 %～ 1 0 1 .6% ,相对标准偏差为 1 .5 %～ 2 .3% .     

2-氯吡啶氮氧化物的合成方法研究

对以2-氯吡啶为原料、双氧水为氧化剂、钨酸和硫酸为催化剂合成2-氯吡啶-N-氧化物的方法进行了反复实验．该方法的最佳反应条件为：催化剂浓H2SO4与2-氯吡啶的体积分数为0．2：1．0～0．3：1．0，2-氯吡啶与钨酸的物质的量比为18．5：1—20．8：1，反应中H2O2与2-氯吡啶的物质的量比为1．3：1～1．5：1，反应最适温度为70～80℃，满足这些条件的反应产率为90％以上．     

光度法测定面粉中的微量水

7，7，8，8-四氰基对二次甲基苯醌可以与醇中的水发生荷移反应，形成的水合物的最大吸收波长为744nm和845nm．在甲醇、异丙醇中，水的含量在0％～7．0％（V／V）范围内与吸光度呈线性关系；在乙醇、正丙醇中测定水的线性范围为0％～8．0％（V／V），方法灵敏度高，重现性好，重复实验相对标准偏差小于2％．反应迅速，操作简便．用拟订的方法测定面粉及醇中的微量水，结果与标准值相符，回收率为98％～102％。     

高效液相色谱法测定烟草中的淀粉含量

研究了用高效液相色谱法测定烟草中的淀粉含量，方法检测限为3．0mg／L，相对标准偏差为1．6-2．1％，标准回收率在95～105％之间。新方法用于几种烟草样品中淀粉含量测定，结果令人满意。     

荷移光度法测定烟草中烟碱的含量

研究了7,7,8,8-四氰基对二次甲基苯醌(TCNQ)与烟碱的荷移反应, 确定 了反 应条件. TCNQ与烟碱形成络合物的反应在743 nm和842 nm处有较强光吸收, 表观摩尔吸 光 系数分别是4.84×10³ L· mol^－１·cm^－１和8.82 ×10³ L· mol^－１·cm^－１. 在乙醇介质中, 烟碱 的浓度在3～35 mg/L与吸光度关系符合朗伯-比尔定律; 该方法重现性好、 灵敏度高、 操 作简单 , 用于测定烟草中烟碱含量, 精密度好, 相对标准偏差为1.4%(n=9), 烟碱的回收 率为98%～103%, 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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