分光光度法测定铜合金中微量铈及铈组稀土

铜基合金中铈及铈组稀土的测定,通常多采用铜试剂分离或铜试剂三氯甲烷萃取分离偶氮胂Ⅲ光度法.但上述方法不能满足测定微量铈及铈组稀土分离富集的要求.又不利于环保.而具有灵敏度高.选择性好的稀土显色剂即不对称变色酸双偶氮衍生物发展很快.其中膦酸型对硝基偶氮氯膦(简称 CPA-PN)已用于镍合金、矿石中铈组稀土的测定.本文基于在硫酸介质中,草酸掩蔽铁(Ⅲ)不影响CPA-PN与铈显色反应的特点,提出在氯化铵存在下,以铁作载体,用氨水先将铁、铈共沉淀与基体铜分离,再用草酸掩蔽铁,CPA-PN与铈显色,借此可测定铜基合金中0.002％～0.02％铈及铈组稀土.     

二溴对氯偶氮甲磺（DBCMSA）光度法测定铈组稀土的研究

研究了新显色剂二溴对氯偶氮甲磺与铈组稀土离子的显色反应。在盐酸、磷酸、高氯酸、 酸、硝酸介质中,与组稀土形成稳定的络合物,最大吸收在６４４ｎｍ。在测定钢样中铈组稀土总量时,反应有很高的选择性,不需加任何掩蔽剂,分析结果与标准值基本相符。     

偶氮氯膦-mN与镧(Ⅲ)显色反应的研究

偶氮氯膦-mN(简称CPA-mN)是稀土元素的一种新型显色剂。曾有文献报道:在掩蔽剂存在下,可用CPA-mN测定钢铁、矿石中的铈组稀土分量和稀土总量。对铈组稀土,灵敏度可达7.8×10~4l·mol~(-1)·cm~(-1)。吴斌才等曾研究Ce-CPA-mN-CPB三元胶束增溶体系的显色反应,使显色灵敏度进一步提高,摩尔吸光系数可达1.9×10~5l·mol~(-1)·cm~(-1).本文研究了镧(Ⅲ)与CPA-mN显色反应的最佳条件,确定了在此条件下络合物组成比为1:4,并在此     

DBC－偶氮胂双峰双波长光度法测定球墨铸铁中稀土

作者研究了ＤＢＣ－偶氮与稀土元素的显色反应．１．７ｍｏｌ／Ｌ盐酸介质中，该试剂与铈组稀土元素形成稳定的蓝紫色配合物．以双峰双波长（测定波长６３０ｎｍ，参比波长５２０ｎｍ）测定时，灵敏度高，表观摩尔吸光系数为１．４９×１０５．稀土含量在０～２０．０μｇ／２５．００ｍＬ范围内呈良好的线性关系，标准偏差小于０．００２％．     

分光光度法测定Al—Ti—B合金中的硼

本文研究了１－羟基－４－－蒽醌与硼的显色反应。实验表明：该显色反应灵敏度高，选择性好。该法用于Ａｌ－Ｔｉ－Ｂ合金中硼的测定，获得满意的结果。     

三氯偶氮胂直接光度法测定金属材料中铈组稀土元素

研究了三氯偶氮胂在盐酸－草酸介质中与钢铁及合金材料中铈组稀土元素的显色反应。试验表明，在盐酸（２Ｍ）－草酸（０．０８Ｍ）介质中，铈组稀土元素与三氯偶氮胂形成稳定的络合物。其最大吸收波长λｍａｘ＝６３０ｎｍ，表现摩尔吸光系数ε＝１．１×１０４Ｌ／ｍｏｌ·ｃｍ，铈组稀土元素与三氯偶氮胂的络合比为１：２。用本法测定了球墨铸铁、合金钢、铝合金、镁合金和钴合金等金属材料中的铈组稀土元素，其结果令人满意。     

氯丙嗪用作新无机分析试剂——氯丙嗪用作高碘酸根的微量快速检定

本文报道了新显色剂盐酸氯丙嗪与高碘酸根显色反应的最佳条件、灵敏度、选择性和界限比,建立了用盐酸氯丙嗪检定高碘限离子的新方法.在约3.6M 硫酸介质中,盐酸氯丙嗪与高碘酸根离子在室温下反应,溶液是桃红色,色泽显明较稳定.检出限量为0.5μg,稀释限为1:2×10~6.在已做过的七十一种离子中,主要干扰离子为金(Ⅲ)、铈(Ⅳ)、铁(Ⅲ).     

一类新的4－取代胂酸型变色酸偶氮多卤显色剂与钍显色反应的研究

本文研究了１１种新型４－取代胂酸型显色剂与钍的显色反应。该组试剂与钍显色，具有对比度大，显色酸度高，灵敏度好等特点．对钍的回收试验结果显示，该方法准确、可靠。     

一类新的4—取代胂酸型变色酸偶氮多卤显色剂与钍显…

本文研究了１１种新型４－取代胂酸型显色剂与钍的显色反应，该组试剂与钍显色，具有对比度大，显色酸度高，灵敏度好等特点，对钍的回收试验结果显示，该方法准确，可靠。     

镓(Ⅲ)溴邻苯三酚红—氯化十四烷基二甲基苄基铵—羧甲基纤维素钠体系显色反应的研究

利用阳离子表面活性剂的吸光光度法近十多年发展很快,使光度分析面貌发生了根本改观,提供了许多优良的高灵敏和高选择性的测定方法。混合表面活性剂的应用目前刚刚开始,但也显示了它的优越性,值得研究。 铁(Ⅲ)和铟(Ⅲ)与溴邻苯三酚红(BPR) —氯化十四烷基二甲基苄基铵(Zeph)—羧甲基纤维素钠(ScMc)体系的显色反应新近有人进行了研究,该体系属于混合表面活性剂共用增敏型络合物显色反应。考虑到镓与铟同属一族,那么镓(Ⅲ)很可能有类似的显色反应,因而对镓(Ⅲ)的显色体系作了研究,探讨了显色反应的最佳条件,用摩尔比法和连续变化法测定了络合物的组成,实验结果证实了我们的设想。镓(Ⅲ)与BPR生成1:2     

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.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

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