离子色谱法测定常见海藻及琼脂中的硫酸根含量

为测定常见海藻及琼脂中的硫酸根含量,建立了测定硫酸根含量的离子色谱内标法,对6种琼脂和5种海藻中的硫酸根含量进行测定.结果表明:选择KNO3作为内标物,硫酸根的质量浓度在10～45 mg/L范围内线性关系良好（R2＞0.999）,加标回收率为93.1%～106.4%.该方法测得的琼脂中硫酸根质量分数在0.25%～1.21%之间,海带、紫菜、麒麟菜、红毛菜和江蓠中硫酸根质量分数分别为2.58%、3.86%、10.62%、2.42%和1.01%,其中麒麟菜的显著高于其他4种海藻的（P<0.05）     

低压离子色谱-化学发光联用在线检测痕量钙

当LuminolH2 O2 Ni2 混合溶液的化学发光 (CL)强度降至稳定基线值后 ,加入碱土金属离子 ,其化学发光强度再次显著增强 .基于此 ,结合低压离子色谱 (LPIC)分离技术 ,建立起Ca2 离子的LPIC CL分离检测新方法 .该方法的线性范围为 8 0× 10 -8～ 6 4× 10 -6g·mL-1,相关系数r=0 9998,检出限为 5 4× 10 -8g·mL-1,相对标准偏差为 1 33% (n =11) .测定牛奶中的Ca2 离子 ,并与原子吸收光度法对照 ,结果令人满意     

基于(Sn,Ba,La)·(PO_4)_3Cl·Eu纳米颗粒荧光猝灭法测定废水中Cr(Ⅵ)

基于Cr(VI)对(Sn,Ba,La)5·(PO4)3Cl·Eu纳米颗粒的荧光猝灭作用,建立了用琼脂溶液来固定分散(Sn,Ba,La)5·(PO4)3Cl·Eu纳米颗粒并用于测定水中微量Cr(VI)的荧光分析新方法.研究表明:Cr(Ⅵ) 离子对固定于琼脂溶液中的(Sn,Ba,La)5·(PO4)5Cl·Eu纳米颗粒有荧光猝灭作用.在pH = 9.0的条件下,测定的荧光最大激发波长和发射波长分别为271 nm和447 nm ,测定Cr(VI)浓度的线性范围为4.0 ×10-6mol/L ～1.4×10-4mol/L ,检测限为2.99×10-6mol/L,回收率为98.9%～103.0%.方法具有良好的重现性和选择性, 一些常见金属离子不干扰测定.应用于环境水中Cr(Ⅵ) 离子含量的测定,结果满意.     

分光光度法测定工作电解液中的微量铁离子

利用邻菲啰啉分光光度法测定铝电解电容器工作电解液中的铁含量,检测波长为510nm,在0.005～1μg·mL-1浓度范围内符合Lambert-Beer'Law,线性回归方程为A=0.199 6C-0.000 1,相关系数为0.999 6,最低检出限为0.000 5μg·L-1,RSD不超过2%,回收率为97.50%～101.25%.实验数据计算得到亚铁离子邻菲啰啉络合物的摩尔吸光系数ε为1.092×104L·mol-1·cm-1.     

卤素动力学分析法研究 Ⅳ 过氧化氢氧化甲基橙催化光度法测定溴离子

基于稀硫酸介质中溴离子催化过氧化氢氧化甲基橙，建立了测定痕量溴离子的新催化光度法．方法灵敏度为2×10－3 mg／L（△A=0．001，b=1cm）．检出限为3×10mg／L．测定溴离子的线性范围为 0．10 ～1．30mg／L.用于测定金属镁与硫酸铵中的溴．     

碳纳米管修饰碳糊电极同时测定铜和铅

制备了碳纳米管化学修饰碳糊电极,采用循环伏安法,在pH为4·20的B-R缓冲溶液中同时对Cu2+和Pb2+进行测定.结果表明,Cu2+和Pb2+浓度分别在3·0×10-6～1·0×10-4mol/L和6·0×10-6～1·0×10-4mol/L范围内呈良好的线性关系,检出限分别为5·6×10-8mol/L和1·8×10-7mol/L,线性相关系数R分别为0·9884和0·9909.     

钡-茜素红二元络合物光度法测定痕量钡

建立了钡-茜素红二元络合物光度法测定痕量钡的新方法.在HAc-NaAc介质中,以聚乙烯醇胶体为保护剂,钡可与茜素红形成BaR 2 二元络合物.实验表明,其最佳反应温度为35℃,反应时间为15min,C Ba2 ( ug/L )在8.0～160 ug/L与△A值符合beer定律,检出限为3.8×10-9g/mL.本方法用于水中痕量钡的测定,结果满意.     

对氨基苯磺酸重氮化偶联反应的光谱特性及其分析应用

在稀盐酸介质中,NO-2与对氨基苯磺酸重氮化后与二盐酸 1 萘基乙二胺偶联生成紫红色偶氮染料,在碱性介质中染料的最大吸收波长位于500nm,表观摩尔吸光系数为2 6×104L·mol-1·cm-1.据此建立了在碱性介质中测定痕量亚硝酸根的吸光光度法.NO-2的浓度在0～2 8mg/L范围内符合比耳定律,对于NO-2的检出限为2 6μg/L.方法用于环境水样、蔬菜、香肠和合成水样中NO-2的测定,回收率为94 0%～105 0%.     

甲基红褪色光度法测定数量溴酸根离子

研究了盐酸介质中 ,在氯化纳的催化作用下 ,溴酸根离子氧化甲基红褪色的最佳条件 .吸收波长为 5 18nm .表观摩尔吸光系数为 7.2×10 4 L· m ol- 1 · cm- 1 ,溴酸根离子在 3.0～ 18μg/2 5 m L范围内符合比尔定律 .方法用于化学试剂中微量溴酸根的测定 ,结果令人满意 .     

用分光光度法间接测定微量硫酸根的研究

本文研究了在酸性介质中,硫酸根与铬酸钡进行交换反应,置换出定量的重铬酸,借助于碘淀粉蓝光度法间接测定微量硫酸根的方法。本法操作比较简单,灵敏度和准确度高,重现性好,线性范围较宽,硫酸根在8～80μg/50ml 符合比尔定律,摩尔吸光系数为4×10~4l·mol~(-1)·cm~(-1).适用于微量硫酸根杂质及能转化为硫酸盐的微量有机硫含量的测定。     

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

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