景东县3种野生草药中重金属含量的测定

目的:测定景东县野生茯苓、何首乌及草血竭中铅、镉、砷、汞的含量.方法:采用原子荧光光谱法测定4种重金属的含量.结果:景东县3种药材中4种重金属含量均≤0.2 mg/kg;各元素测定的线性关系良好,r=0.999 5～0.999 8;精密度测定RSD<5.0%(n=6),重复性试验RSD<5.0%(n=5),加样回收率在99.4%～103.0%.结论:景东县3种野生草药中的重金属含量均未超标.     

云南部分地区木香中重金属含量的测定

目的:检测花甸坝药材场、银桥及中甸所产木香中镉、铅、砷、汞的含量.方法:采用原子荧光光谱法测定4种重金属含量.结果:3个地区木香中检测出的重金属镉≤0.011mg/kg、铅≤3.5mg/kg、砷≤0.11mg/kg、汞≤0.002 6mg/kg,含量均低于<药用植物及制剂进口绿色行业标准>限定值.各元素线性关系良好,r≥0.9993,回收率为99.10%～102.20%,RSD<5%(n=6).结论:花甸坝药材场种植的木香重金属(除铅外)的含量较另外两个地区的低.     

微波消解-原子荧光光谱法测定沙棘产品中的铅、砷、汞

为建立沙棘PV粉、沙棘油中铅、砷、汞的原子荧光光谱检测方法,通过试验确定了样品前处理方法,对负高压、灯电流、载气、屏蔽气、原子化气高度、酸度等测试条件进行了优化。在优化的工作条件下,用原子荧光光谱法测定其中的铅、砷、汞的含量。结果表明:对所测元素铅、砷、汞,校准曲线的相关系数分别为:0.999 7、1.000 0、0.999 9;检出限分别为:0.000 1、0.000 2、0.000 02 mg/kg;相对标准偏差为1.2%~4.83%;用加标回收率评价方法的准确性,回收率为92%~105%。该方法快速、简便、准确且灵敏度高,为沙棘产品中重金属含量测定提供了较好的方法。     

原子吸收分光光度法测定资丘木瓜中3种重金属含量

建立了测定资丘木瓜药材中铜、铅和镉三种重金属含量的方法:采用火焰原子吸收光谱法检测铜的含量,以石墨炉原子吸收光谱法检测铅和镉的含量.3种重金属测定的检测限为0.0006μg/mL、0.0030ng/mL、0.0024ng/mL,相对标准偏差(RSD)为2.7%、2.9%、1.2%,回收率为100%¹05%,线性相关系数为0.999和0.992、0.995,均符合要求.经测定3批资丘木瓜药材中铜、铅、镉的含量分别为13.53105%,线性相关系数为0.999和0.992、0.995,均符合要求.经测定3批资丘木瓜药材中铜、铅、镉的含量分别为13.53¹6.24 mg/kg、0.016316.24 mg/kg、0.0163⁰.0232 mg/kg、0.22670.0232 mg/kg、0.2267⁰.3364 mg/kg,结果表明:3批木瓜样品中重金属的含量均符合《药用植物及制剂进出口绿色行业标准》中有关重金属标准的规定.     

氢化物发生原子荧光法测定土壤中铅镉砷3种有害重金属

应用氢化物发生-原子荧光法对土壤中铅镉砷含量进行测定。研究了分析测定条件;测定铅、镉、砷的线性范围分别为:0～40μg/L,0～5μg/L,0～40μg/L;相关系数分别为:0.9999,0.9999,0.9994。应用于样品测定,测定结果的相对偏差小于2.6%;加标回收率为96.8%～104%。     

大理花甸坝药材场五种药材中重金属含量的测定

目的：对大理花甸药材场种植的附子、川芎、木香、三分三和大黄中砷、汞、镉、铅4种重金属元素的含量进行测定和分析。方法：采用原子荧光分光光度法,并对测定方法进行了方法学考察。结果：在最佳工作条件下对四种重金属元素进行测定,平均回收率在97.61%～102.18%,RSD在0.001%～1.04%。结果显示,五种药材中砷、汞、镉、铅4种重金属测定结果符合2005年版药典中重金属含量的限量标准。结论：该测定方法操作简便,快速,精密度及准确度高,适用于五种大宗药材中4种重金属含量的测定。     

电感耦合等离子体质谱法测定谷类产品中7种元素

为建立准确、快速地同时测定谷类产品中微量重金属元素含量的方法,采用电感耦合等离子体质谱法测定藜麦和绿豆芽等谷类产品中砷、镉、铅、锰、铜、锌和铁等7种微量重金属元素.以硝酸和双氧水消解样品,调谐优化仪器分析条件,锌、砷、铜、锰和铁等5种元素选用KED模式,铅和镉选用STD模式,以标准曲线法进行测定.结果显示：砷、镉、铅、锰、铜、锌和铁的线性回归方程分别为y=1.49×10²x+0、y=3.06×10²x+0、y=1.026 7×10⁴x+0、y=1.029×10³x+0、y=1.088×10³x+0、y=2.67×10²x+0和y=3.4×10¹x+0;砷、镉、铅、锰和铜的线性范围均为0.10～800.0μg·L^-1,锌的线性范围为5.00～300.0μg·L^-1,铁的线性范围为5.00～800.0μg·L^-1,相关系数均在0.999 4～0.999 6之间;检出限在6....     

青海湖裸鲤肌肉营养成分和微量元素的分析

采用常规生化分析方法测定了20尾青海湖裸鲤肌肉营养成分,并首次对鱼肌肉中微量元素进行检测。结果显示：鱼肌肉中蛋白质含量为19.28%,脂肪为1.73%,灰分为1.25%,水分为78.38%。在测定的汞、砷、铜、锌、铅和镉6种微量元素中,汞的含量为0.123 4 mg/kg,砷为0.130 6 mg/kg,铜为0.255 mg/kg,锌为2.255 mg/kg,铅为3.485 mg/kg,镉为0.09 mg/kg。其中锌的含量超过国家食品规定标准将近7倍。     

ICP-MS法测定食品添加剂氢氧化钠中五种重金属

目的:建立对基础干扰大的食品添加剂氢氧化钠中重金属的快速测定方法。方法:利用ICP-MS同时测定了食品添加剂氢氧化钠中砷、铅、镉、汞、铬五种重金属元素。结果:该方法完全克服了本体干扰大的缺点,五种元素标准曲线呈现良好的线性相关性,线性相关系数落在0.999 0~0.999 9的范围内;五种元素样品重复测定相对标准偏差(RSD)均小于3.7%,检出限在0.03~0.09 ug/L之间,加标回收率在91%~102%之间。结论:实现了对食品添加剂氢氧化钠中五种微量重金属元素准确快速分析。     

南方典型稻田土壤-水稻系统环境质量评价

为研究南方典型区域稻田土壤—水稻系统中重金属含量,系统采集了江西省进贤县、金溪县、渝水区、高安市、安福县和兴国县等6个水稻主产区典型田块土壤、水稻和灌溉水,重点分析了土壤和水稻铅、镉、砷和汞含量及其土壤养分,并采用单因子污染指数和内梅罗综合指数对土壤—水稻系统中重金属含量进行评价。结果表明,研究区稻田土壤pH、有机质、总氮、总磷、总钾、碱解氮、有效磷和速效钾总均值分别为5.48、32.99 g/kg、2.06 g/kg、0.54 g/kg、16.04 g/kg、156.71 mg/kg、14.00 mg/kg和94.98 mg/kg。研究区土壤铅、镉、砷和汞含量总均值分别为35.46、0.18、7.21和0.17 mg/kg,单因子污染指数均小于1,内梅罗综合污染指数为0.56,土壤环境质量等级为清洁;但渝水土壤镉含量为0.37 mg/kg,超过限量标准(0.30 mg/kg),土壤环境质量属于警戒状态。研究区糙米铅、镉、砷和汞的含量总均值分别为0.06、0.17、0.24和0.0086 mg/kg,单因子污染指数均小于1,内梅罗综合污染指数均值为0.77,糙米环境质量等级为警戒限;但兴国和渝水糙米镉含量分别为0.22和0.35mg/kg,均超过限量标准(0.20 mg/kg),环境质量等级分别为警戒限和轻度污染。相关性表明,糙米镉与土壤镉和铅呈显著正相关,而与土壤砷呈显著负相关;糙米砷与土壤砷和有效磷呈显著正相关。总之,重金属镉是调查区域水稻安全性最主要的潜在污染元素,需重点关注兴国和渝水两地水稻食品安全。     

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

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