氢化物发生原子荧光法同时测定丹参中痕量砷和锑

采用L-半胱氨酸做预还原剂,建立了氢化物发生原子荧光光谱法测定丹参中砷、锑含量的方法.研究了酸度、硼氢化钾浓度、L-半胱氨酸浓度等条件对原子荧光强度的影响.结果表明,在最佳工作条件下,砷、锑检出限分别为0.09μg/L和0.03μg/L;在取样量为1.000g时,砷、锑的检出限分别为1.13 ng/g和0.38ng/g.本方法操作简单、灵敏度高、分析速度快,适用于植物药材及其制剂中痕量砷、锑含量的检测.     

微波消解-氢化物发生-原子荧光光谱法同时测定食品中的As和Hg

应用微波消解-氢化物发生-原子荧光光谱法测定食品中微量砷(As)和汞(Hg)的含量,实验结果表明,在最佳条件下,该法的回收率分别是:砷为94.5%～101%,汞为92%～96%,相对标准偏差值为1.0%～1.66%,As和Hg的检出限分别为0.1μg·L-1和0.02μg·L-1,其线性范围分别为1.0～100μg·L-1和0.2～60μg·L-1.该法能满足各类食品中微量砷和汞含量的测定要求,具有分析速度快、操作简便、检验效率高等特点.     

氢化物原子荧光光度法测定大米中的总砷含量

以强氧化剂硝酸十高氯酸(4:1)湿法消解样品,使用氢化物原子荧光光度法测定大米中的总砷含量,并对仪器的工作条件进行了优化.结果砷浓度0～10μg·L-1标准曲线的线性方程为If=361.037C+ 30.859,相关系数0.9999,精密度0.8％,检出限0.0058μg·L-1,回收率为95.0％～110.0％.该方...     

断续流动原子荧光光谱法测定水中砷的研究与应用

建立一种氢化物原子荧光光度法测定自来水中砷(As)含量的方法.在实验条件下,测定自来水中的砷,经统计计算得标准偏差为2.65,相对标准偏差为0.87%.此方法可用于水中砷的测定.     

优化的原子荧光法测定砷汞含量

建立了用AFS-830双道原子荧光光度计同时测定不同样品中砷和汞的氢化物发生-原子荧光法检测方法.在优化的仪器工作条件下:砷和汞的线性检测范围广,分别为0~10μg/L和0~1μg/L;方法灵敏,检出限分别为0.042μg/L和0.038μg/L;样品加标回收率高,分别为99.5%~100.1%和97.5%~99.9%,可用于工业环境监测中测定不同样品中的砷和汞的含量.     

用AFS-230E原子荧光光度计测定地表水中的砷

砷是我国实施排放总量控制的主要指标之一。根据AFS-230E原子荧光光度计测定原理及方法,测定了地表水中的砷,结果表明:方法的线性关系良好,相关系数0.999 8,检出限0.087μg.L-1,相对标准偏差0.5%,加标回收率95.0%~104%,令人满意。     

以氢化物发生-原子荧光光度法测定保健品中的砷元素

目的：对氢化物发生-原子荧光光度法测定保健品中的砷元素残留进行方法学研究。方法：选用砷标准溶液对氢化物发生-原子荧光光度法测定砷残留进行方法学研究,并对我公司生产的鳕鱼肝油软胶囊中的砷进行检测。结果：氢化物发生-原子荧光光度法测定保健品中残留的砷具有较高的灵敏度,0ng/ml至0.2ng/ml浓度范围内的线性、精密度良好,以该方法检验的鳕鱼肝油软胶囊产品中砷元素残留量,供试品溶液2小时内的稳定且重现性良好。结论：氢化物发生-原子荧光光度法能够用于保健品中的砷元素测定,以监控其质量。     

中成药药用胶囊中4种有毒金属元素测定方法

对中成药药用胶囊中铬、镉、砷、铅4种有毒金属元素的含量进行了测定.利用V（HNO3）∶V（HF）∶V（H2O2）=4∶1∶1的混合酸体系,消解含有Ti、Si氧化物的药用胶囊.采用石墨炉原子吸收光谱法（GF-AAS）和电感耦合等离子体发射光谱法（ICP-OES）对样品中的4种有毒金属元素进行了测定.结果表明：4种中成药药用胶囊中铬的含量均符合2010年版《中国药典》（二部）明胶空心胶囊标准要求,镉、砷、铅3种元素含量也均符合我国《药用植物及制剂进出口绿色行业标准》规定.说明两种方法均可以满足中成药药用胶囊中铬、镉、砷、铅4种金属元素的检测.对于高含量的样品,ICP-OES法简便、快捷、高效;而对于低含量的样品,GF-AAS法加标回收率更好,准确度更高.     

原子荧光光谱法测定自来水中砷含量

由于人为造成的污染,导致我们生存的环境,包括大气、土壤、水质、食品等都受到了不同程度的破坏,为了人类自身健康,这些污染应该引起每个人的高度重视。砷的化合物是有剧毒的物质,对它的检测具有重要的意义。本论述采用AFS一230E原子荧光光度计测定了自来水中的砷含量,绘制了标准曲线,线性关系良好,测定了检出限、相对标准偏差及样品回收率,取得了理想的结果,证明用原子荧光光谱测定自来水中砷含量的方法可行。     

应用氢化─原子荧光法测定钢材中的砷

研究了低温氢化-原子荧光法测定钢材中的砷时,介质、酸度等条件对测定的影响及常见元素的干扰情况,建立了用低温氢化-原子荧光法测定钢材中砷的分析方法.该方法简便快捷,用于钢材中砷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.     

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     

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

正~~