蜂蜜中多种有机磷农药残留的液相色谱串联质谱检测

针对敌百虫、敌敌畏和蝇毒磷为常用的防治蜜蜂天敌或虫害的有机磷农药杀虫剂,易在蜂蜜中产生残留,建立了蜂蜜中敌百虫、敌敌畏和蝇毒磷残留的液相色谱串联质谱(LC-MS/MS)同时测定方法。蜂蜜样品经乙酸乙酯提取、浓缩,用甲醇溶解残渣,液相色谱(LC)分离,电喷雾(ESI)-MS/MS多反应监测(MRM)模式检测,外标基体曲线定量。3种有机磷农药在20～500μg/L范围内线性响应良好,相关系数均大于0.994;获得的检出限均为0.1μg/kg,定量限均为4μg/kg。在加标浓度为10～40μg/kg范围内,平均回收率为78.5%～96.8%,相对标准偏差为9.1%～13.1%。     

三唑磷和乙酰甲胺磷对海洋桡足类的急性毒性研究

研究了三唑磷和乙酰甲胺磷两种常用有机磷农药对婆罗异剑水蚤和日本虎斑猛水蚤的急性毒性,报道了相关的24hLC50和48hLC50数据.其中三唑磷对婆罗异剑水蚤和日本虎斑猛水蚤的48hLC50分别为6.844μg/L和16.26μg/L,而乙酰甲胺磷对婆罗异剑水蚤和日本虎斑猛水蚤的48hLC50分别为216.3 mg/L和76.54 mg/L.结果表明:对两种桡足类而言,三唑磷的毒性大于乙酰甲胺磷;桡足类对有机磷农药的耐受性具有种的特异性.据此提出使用农药的相关建议,指出应该严格控制三唑磷的使用,为近岸海区环境的质量评价和污染防治提供参考依据,并为监测有机磷农药污染环境提供了参考资料.     

固相萃取-液相色谱法分析环境水样中有机磷农药残留

提出环境水样中有机磷农药残留的固相萃取-液相色谱分析方法.水样用0.22μm水系膜过滤两次,C18固相萃取小柱分离富集,用乙腈洗脱目标物,洗脱液直接进行液相色谱分析.结果显示,工作曲线范围分别为甲基对硫磷2.0～80μg/L、杀螟硫磷3.0～80μg/L、对硫磷3.0～100μg/L、辛硫磷5.0～100μg/L、检测限(LOD)分别为甲基对硫磷0.11μg/L、杀螟硫磷0.52μg/L、对硫磷0.45μg/L、辛硫磷0.85μg/L.加标回收率在84.2％～102.2％范围内.该方法操作简单、快速、低成本、高回收率、富集效果好,适合于环境水样中有机磷农药残留的分析检测.     

微型流动注射化学发光仪测定蔬菜中残留的有机磷农药

目的利用便携式流动注射化学发光仪和紫外降解装置,检测蔬菜中残留的有机磷农药。方法过硫酸钾在紫外光的催化下能将有机磷降解为无机磷,无机磷在酸性条件下可以和钒酸盐、钼酸盐反应生成具有氧化性的磷钼钒杂多酸,可直接氧化鲁米诺产生强而稳定的化学发光信号;根据发光强度与磷的浓度在一定范围内呈线性关系,从而实现有机磷农药的定量测定。结果测定磷的检出限为1.0×10-10g/mL,线性范围为1.0×10-9~3.0×10-6g/mL,对浓度为2.0×10-7g/mL的磷平行测定11次,相对标准偏差为2.1%;当青菜中有机磷农药的添加浓度为1.00 mg/kg和2.00 mg/kg时,方法回收率在89.5%~113.5%之间。结论此方法简便快捷、准确可靠,实现了检测仪器的自动化和微型化,为市售蔬菜中有机磷农药残留的现场检测奠定了基础。     

椭圆背角无齿蚌对重金属元素的积累作用

 检测了滇池水饲养1a的椭圆背角无齿蚌(Anodonta woodiana elliptica)体内重金属等元素含量,结果显示椭圆背角无齿蚌体内锌含量为7.08×10²mg/kg,铅为35.68mg/kg,铜为9.04mg/kg,铁为4.74×10³mg/kg,砷为62.09mg/kg,磷为4.44×10⁴mg/kg.与滇池水中锌0.0205μg/L,铅0.412μg/L,铜3.198μg/L相比较,表明椭圆背角无齿蚌对锌、铅、铜有很强的富集能力.     

金银花等3种中药材中有机磷农药残留量的测定

对中药材金银花中11种有机磷农药残留量的气相色谱方法进行了研究.样品中的农药采用乙腈-水系统提取,经氮吹浓缩,选用火焰光度检测器(FPD)和DA-5毛细管柱,采用程序升温,气相色谱法检测.方法的最低检出浓度为1.0×10-3～6.0×10-3μg/mL,仪器精密度为1.4%～4.7%;方法精密度为1.2%～6.0%;加样回收率为88.0%～104.6%,RSD值为2.6%～8.9%.用该方法对金银花、泽泻和川芎中有机磷农药残留量进行了测定,结果表明,3种中药材均不同程度地受到有机磷农药的污染,依照《欧洲药典》7.0版农药残留最大限量规定,金银花不合格率为60%,泽泻不合格率为40%,川芎不合格率为10%.     

邕江南宁段和南宁城市内河中的有机磷农药调查

在邕江南宁段和南宁城市内河的西明江、可利江、心圩江、朝阳溪、大桥冲、水塘江、竹排冲设置采样点,分别在枯水期和丰水期采集水样,用固相萃取-气相色谱／脉冲火焰光度检测器检测三乙基偶磷硫酯、硫磷嗪、致螟磷、甲拌磷、乐果、乙拌磷、甲基对硫磷、对硫磷和氨磺磷9种有机磷农药的含量,分析水体中有机磷农药组成及污染状况。结果共检出甲拌磷、乐果、乙拌磷、对硫磷、甲基对硫磷和氨磺磷6种有机磷农药。邕江南宁段仅在丰水期检出乐果和氨磺磷2种有机磷农药,含量0．03～0．04μg／L。南宁城市内河枯水期检出甲拌磷、乐果、乙拌磷、对硫磷4种有机磷农药,总含量0．09～6．82μg／L,含量最高的是朝阳溪的样品;丰水期检出乐果、乙拌磷、甲基对硫磷、氨磺磷4种有机磷农药,总含量0．08～6．60μg／L,含量最高的是大桥冲的样品。     

水产品中有机磷农药多残留的固相萃取-气相色谱串联质谱测定

通过比较不同的提取剂和吸附剂对水产品的净化效果和对质谱基线的影响,建立一种有效的水产品中有机磷农药多残留的气相色谱-三重四极杆串联质谱(GC-MS/MS)方法。用正己烷对样品进行提取处理,采用N-丙基二乙胺(PSA)和硅胶柱进行固相萃取,用GC-MS/MS多反应离子监测(MRM)模式测定。结果表明,在5～200μg·L-1范围内,28种有机磷农药的峰面积与对应的质量浓度间呈良好的线性关系,相关系数R20.996 8,方法的定量限(S/N=10)为0.2～7.9μg·kg-1,在大黄鱼中各农药的回收率为67%～99%之间,相对标准偏差(RSD)在5.3%～13.6%(n=6)之间,在南美白对虾中各农药的回收率为73%～106%之间,相对标准偏差(RSD)在4.6%～12.8%(n=6)之间。该方法较为灵敏、准确、简便,可用于检测水产品的有机磷农药残留情况。     

离子液体分散液液微萃取-高效液相色谱分析苹果中有机磷农药残留

建立了苹果中有机磷农药残留多组分同时定量分析的离子液体分散液液微萃取-高效液相色谱分析(IL-DLLME-HPLC)方法.以[C6MIM][PF6]离子液体为萃取剂,甲醇为分散剂,对样品体积、萃取温度和萃取时间等萃取条件进行优化.结果显示,苹果样品中哒嗪硫磷、对硫磷、倍硫磷和伏杀硫磷4种有机磷在20～2000μg/kg...     

茶叶中水胺硫磷、亚胺硫磷、甲基对硫磷和伏杀硫磷农药残留的高效液相色谱法测定

建立了茶叶中4种有机磷农药──水胺硫磷、亚胺硫磷、甲基对硫磷和伏杀硫磷残留的高效液相色谱测定方法.在45℃加温条件下用乙酸乙酯-正己烷(1◇1,by vol.)混合溶剂提取待测目标物、活性炭层析柱净化,用10.0 mL乙酸乙酯-正己烷(6◇1,by vol.)淋洗待测组分,以Eclipse XDB-C8色谱柱、乙腈-水混合液梯度洗脱分离、二极管阵列检测器测定.结果表明,上述4种农药在6.5 min内能很好地分离;样品中添加的待测组分能定量回收,回收率89.0%~108.0%,相对标准偏差为1.89%~5.96%(1.0μg/mL,n=5),检出限分别为:水胺硫磷9.82μg/kg、亚胺硫磷7.88μg/kg、甲基对硫磷2.19μg/kg、伏杀硫磷0.72μg/kg(dm).     

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     

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