催化动力学光度法测定痕量钒

研究了在H_2SO_4介质中,微量钒能显著催化氯酸钾氧化核固红(1-氨基-2,4-二羟基蒽醌-3-磺酸钠)(C.I.No.60760)褪色。研究了反应的动力学行为,建立了测定痕量钒的催化动力学分析方法。该方法的检出限为6.9×10~(10)g/ml,线性范围为0.005～1.8μg/25ml用于测定中草药及食品中的痕量钒,结果满意。     

阻抑动力学光度法测定痕量钒(V)的研究

文章研究了在酸性介质中,痕量钒(V)能强烈抑制抗坏血酸氧化次甲基蓝褪色的指示反应,探讨了阻抑褪色反应的最佳条件和动力学参数,建立了测定痕量钒的新方法,该方法的线性范围为8.72×10-8-4.36×10-5g.mL-1,检出限为6.10×10-9g.mL-1.用于井水、矿泉水中痕量钒的测定,结果满意。     

丁基罗丹明B—溴酸钾—溴代十六烷基吡啶体系催化光度法测定痕量钒的研究

本文研究了在柠檬酸介质中,有溴代十六烷基吡啶存在时钒催化溴酸钾氧化丁基罗丹明B的褪色反应,建立了催化光度法测定痕量钒的新方法．本方法的线性范围为0．010－0．200μg／25ml,检出限为13×10－10g／ml．用于岩石中痕量钒的测定,结果满意．     

催化光度法测定痕量钒的研究

本文研究了在稀硫酸介质中,痕量钒催化溴酸钾氧化3—氨基—6—二甲氨基—2—甲基吩嗪盐酸盐褪色的新指示反应,建立了催化光度法测定痕量钒的新方法。方法的灵敏度为3.03×10~(-11)g/ml,线性范围为0—0.25μg/25ml,用于水、土壤和粮食样品中痕量钒的测定,获得满意结果。     

催化光度法测定痕量钒的研究和应用

本文基于在抗坏血酸存在下,钒对KBrO_3氧化甲基绿褪色的新指示反应,建立了一个测定痕量钒的催化光度新方法。方法检出限2.81×10~(10)g/ml。测定范围为0-16ng/25ml钒。用于人发、水样品中钒的测定,结果满意。     

阻抑溴酸钾氧化二甲基黄光度法测定痕量钒

研究了痕量钒(V)阻抑溴酸钾氧化二甲基黄的褪色反应, 确定了最佳反应条件, 建立了一种光度测定痕量钒(V)的新方法.结果表明, 方法的检出限为2.3×10-10g/mL, 线性范围为0.40-4.0μg/L.用于化学试剂中痕量钒(V)的测定,结果满意.     

新指示反应测定痕量钒的研究及应用

测定痕量钒的报道已有不少．本文研究了钒的另一新指示反应．在稀Ｈ２ＳＯ４介质中，ＫＢｒＯ３氧化碱性染料孔爸绿褪色反应缓慢，有抗坏血酸存在时．痕量量钒折加入使褪色反应速度显著加快．确立了最佳反应条件，测定了表观活化能，建立了高灵敏测定痕量锐的催化光度新方法．方法检出限为２．１４×１０－１２ｇ／ｍｌ．线性范围为０—２０ｎｇ／２５ｍｌ．用于发样、水样中痕量钒的测定，结果满意．     

微波消解催化褪色光度法测定痕量I~-的研究

研究了微波密闭消解 I- 催化碘酸根氧化灿烂绿褪色的适宜条件与影响因素 ,建立了催化动力学褪色光度法测定痕量 I- 的新方法 .方法的相对标准偏差 RSD%为 4 .4 0 % ,回收率 CV%为 97.6 0 %～ 10 1.70 % ,实际样品中 I- 的测定 ,简快、可靠 ,结果令人满意     

催化动力学光度法测定痕量钒(Ⅴ)

研究了在酸性介质中痕量钒 (Ⅴ )催化KIO3 氧化变色酸及抗坏血酸体系的反应和动力学条件 ,建立了催化动力学光度法测定痕量钒 (Ⅴ )的新方法.该方法的检出限为0.04μg/L ,线性范围为0～0.5mg/L ,该方法用于水样及人发中痕量钒(Ⅴ)的测定 ,结果令人满意.     

水中痕量锰的测定

本文研究了在NH3·H2O-NH4Cl介质中锰催化过氧化氢氧化苋菜红的褪色反应及其动力学条件,建立了测定痕量锰的新方法.该方法的检出限为5.6×10-4μg/mLMn,线性范围为0～1.8μg/25mL Mn,用于测定井水中痕量Mn,获得满意结果.     

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