便携式分光光度法快速测定水中铁方法研究

对3种便携式分光光度计快速测定水中铁的方法进行了优化和比对研究.通过研究各仪器性能指标以及测定实际水质样品,对不同便携式分光光度计的优势进行了比较,为突发性环境污染事故应急监测选择合适的监测仪器提供了技术参考.结果表明:ZZW-Ⅱ测试仪快速测定水中铁的方法检出限(0.2 mg/L)高于JH916检测仪和PORS-15V光谱仪的方法检出限(分别为0.01 mg/L和0.04 mg/L),在突发性环境污染事故应急监测中,JH916检测仪和PORS-15V光谱仪具有相对较高的灵敏度.ZZW-Ⅱ测试仪和PORS-15V光谱仪快速测定水中铁的方法精密度相近,其测试结果相对标准偏差(RSD)均未超过6.5%(n=6),JH916检测仪快速测定水中铁的方法精密度稍差,其相对标准偏差(RSD)最大值为10.9%.测试实际样品时,加标回收率分别为80.5%~98.0%(ZZW-Ⅱ测试仪)、82.5%~118%(PORS-15V光谱仪)、86.5%~104%(JH916检测仪),表明3种便携式分光光度计均有较好的准确度.3种便携式分光光度计与实验室分析方法相比,测试结果相对偏差较大,相对偏差最大值分别为-18.8%(ZZW-Ⅱ测试仪)、-19.7%(PORS-15V光谱仪)、-25.9%(JH916检测仪).     

便携式分光光度法测定水中水合肼的研究

研究了便携式分光光度计在环境应急监测中对水中水合肼的测定方法,选取ZZW-Ⅱ水质多参数现场测试仪,研究了该仪器性能指标以及对实际水质样品测定.结果表明:ZZW-Ⅱ测试仪快速测定水中水合肼方法检出限为0.04 mg/L,测定下限为0.16 mg/L,加标回收率为84%~90%,相对标准偏差为0%~6.2%该仪器操作简单快捷,比较适合用于环境污染事故现场水合肼应急监测.     

便携式分光光谱仪测定水中氯化物含量

PORS-15浸入式便携分光光谱仪测定水中氯化物，与国家标准方法比对无显著差异。氯化物浓度在0．5～50mg／L范围内与吸光度呈线性关系，线性相关系数为r=0．998，加标回收率97％-106％，测定结果相对标准偏差1．8％～4．1％（n=6）。满足水质监测分析方法中对氯化物测定的限值要求。     

高碘酸钾分光光度法测定水中锰(Ⅱ)的改进

提出加入柠檬酸钠以掩蔽水体中Ca2+对锰(Ⅱ)测定产生的干扰,改进国家标准GB/T 11906-1989中高碘酸钾分光光度法测定水中锰(Ⅱ)的方法.结果表明:所建立方法的线性范围为0.20～20.00mg.L-1,相关系数R2为0.999 3,检出限为0.05mg.L-1,标准加入回收率为95.8%～101.4%,相对标准偏差(RSD)为0.15%～2.47%(n=3).     

超高效液相色谱-三重四级杆质谱法测定地表水中丙烯酰胺

采用旋转蒸发浓缩-超高效液相色谱-三重四级杆质谱法测定水中丙烯酰胺,选择V(甲醇)∶V(水)=5∶95为流动相,该方法有机溶剂使用量少,操作简便.20倍浓缩后,水样中丙烯酰胺的检出限为0.000 05 mg/L,实际水样的加标回收率为87%~111%,方法的相对标准偏差小于7%.该方法能满足《地表水环境质量标准》中相关标准限值要求.     

单扫描极谱法测定瓜子中痕量铅的研究

提出单扫描极谱法测定瓜子中痕量铅的新方法.在6%溴化钾、1%酒石酸钾钠、0.7%盐酸、5%磷酸、2%盐酸羟胺、3%(体积)三乙醇胺混合底液中,以单扫描极谱法对瓜子中痕量铅进行了测定.实验表明,铅在滴汞电极上于-0.47 V(相对饱和甘汞电极)处产生一灵敏催化极谱波,铅浓度在0.2 ng/mL~300 ng/mL范围内与极谱峰电流有良好分段线性关系.检出限为0.16 ng/mL.方法的RSD为2.2%~4.2%,加标回收率为89%~99%.此法仪器试剂简单,操作快速简便,用于实际样品测定,结果满意.     

溶出伏安镉内标法测定水源水中的铅

本文采用PS4.0微机极谱仪的内标分析法定性定量视窗用镉做为内标物测定了水源水中的微量铅,采用检测下限0.3μg/L,线性范围0.3～260μg/L,相对标准偏差为8.90%,回收率为96.4%。溶出分析条件:富集电位-1.0伏,富集时间60秒,静化时间10秒;净化电位0伏,扫描速度250mV/s。波型为一阶导数。参考峰铅-0.46V。锌、锰、铜不干扰测量。     

火焰原子吸收法测定傣药人面果树茎皮中7种微量元素的含量

采用传统消解法对傣药人面果树茎皮进行消解,并在火焰原子吸收分光光度计最佳工作条件下,用外标法测定药中锌、铜、锰、钴、铁、铅、镉7种微量元素的含量,并计算其溶出率.结果显示,7种元素在原药及汤剂中的含量不同,其含量顺序为FeCuMnZnPbCoCd.它们的溶出率也有一定差异,Cd的溶出率最大,Zn的溶出率最小.实验检出限均小于0.003 8μg/m L,加标回收率在93.25%~109.6%之间,相对偏差RSD≤2.90%,测定的结果精密度和准确度令人满意,可为傣药人面果树的有效成分研究提供基础数据.     

衍生化-紫外分光光度法定量分析1,5-萘二异氰酸酯

采用衍生化-紫外分光光度法定量分析了1,5-萘二异氰酸酯(NDI).用NDI与甲醇衍生反应生成1,5-萘二氨基甲酸甲酯后,用紫外-可见光分光光度计和外标法建立了工作曲线.测定结果:NDI质量浓度在15.0～65.0 mg/L范围内线性良好,回收率99.77%～103.24%,相对标准偏差小于0.15%.     

对浸入式便携分光光谱仪测定地表水中氟化物含量的准确性评价

采用PORS-15浸入式便携光谱仪测定地表水中氟化物的含量,与国家标准方法测定结果比对无显著偏差。氟化物浓度在0.1～2.0mg/L范围内与吸光度呈良好的线性关系,线性相关系数为r=0.9996。加标回收率为98%～104%,测定结果的相对标准偏差为0.8%～2.0%(n=6)。满足地表水监测分析方法中关于氟化物测定的限值要求。     

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