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1.
本文研究了在稀盐酸介质中,痕量铁(Ⅲ)对过氧化氢氧化煌焦油兰褪色指示反应的催化作用,建立了催化光度法测痕量铁(Ⅲ)的新方法.方法的线住范围为0—2μgFe(Ⅲ)/25ml,检出限为3.23×10-10g/ml.方法用于人发中痕量铁(Ⅲ)的测定.  相似文献   

2.
动力学光度法测定痕量铁的研究   总被引:3,自引:0,他引:3  
本文研究了氨水介质中,痕量铁(Ⅲ)催化过氧化氢氧化罗丹明B褪色的新指示反应及其动力学条件,建立了动力学光度法测定痕量铁(Ⅲ)的新方法。方法的灵敏度为1.82×10 ̄(-10)gFe(Ⅲ)/ml,测定范围为0—0.8μgFe(Ⅲ)/25ml。用于测定人发及水中痕量铁(Ⅲ),结果满意。  相似文献   

3.
研究了硫酸介质中,草酸存在下,痕量铁(Ⅲ)催化氯酸钾氧化番红花红T褪色的新指示反应及动力学条件,建立了动力学直接测定痕量Fe3+的方法.方法的灵敏度为3.3×10-10Fe3+/ml,测定范围0~0.4μg/ml,操作简便、快速.用于测定人发中的铁,结果满意.  相似文献   

4.
灿烂绿—溴酸钾体系催化光度法测痕量钒(V)的研究   总被引:1,自引:0,他引:1  
本文研究了在柠檬酸介质中,痕量钒催化溴酸钾氧化灿烂绿褪色的新指示反应,建立了一个测定痕量钒的新方法.线性范围为002—0.10μ25ml和012—0.33μg/25ml,方法灵敏度为6.43×10-11g/ml.用于人发、水样品中机的测定,结果满意.  相似文献   

5.
采用流动注射技术,研究了由Jones柱产生的铁(Ⅱ)与光泽精的化学发光反应,建立了新的测定铁的化学发光分析法.方法的检出限为4×10-12g/mL铁,相对标准偏差为2.0%(2×10-8g/mL铁,n=11),线性范围为1×10-11g/mL~1×10-5g/mL.该法用于一些化学试剂和镁合金中痕量铁的测定,结果令人满意.  相似文献   

6.
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.  相似文献   

7.
催化动力学光度法测定痕量钒的新体系   总被引:1,自引:0,他引:1  
在酸性条件下,溴酸钾氧化铬蓝黑B的反应,钒具有极高的催化活性,以此建立了测定痕量钒的催化动力学光度法,方法的线性范围为0~2ng/ml,灵敏度为1.11×10-11g/ml,应用于水及人发中痕量钒的测定,结果满意.  相似文献   

8.
本文基于酸性介质中,痕量亚硝酸根催化溴酸钾氧化二甲苯蓝FF的高灵敏褪色反应,建立了一个测定痕量亚硝酸根的新方法。线性范围为2~40ng/25ml,检出限为9.4×10-11g/ml。用于土壤样品和环境水样品中亚硝酸根的测定,均获得满意结果。  相似文献   

9.
催化动力学方法测定自来水中的痕量锰   总被引:2,自引:0,他引:2  
本文研究了锰离子对高碘酸钾氧化结晶紫退色反应的催化动力学条件,从而建立了痕量锰的催化光度分析方法,锰量在0 ̄0.5μg/25ml范围内符合郎伯-比耳定律。最大吸收波长580nm。检测限为4.0×10^-10g/ml。用本法测定自来水中的痕量锰有较高的灵敏度,从而取得了满意的结果。  相似文献   

10.
pH=2.0的H2SO4介质中,钴(Ⅱ)对KIO4和H2O2氧化中性红(NR)的褪色反应有明显的催化作用,据此建立了测定痕量钴(Ⅱ)的催化动力学光度法,可测定2×10-8~4×10-7g/ml的钴(Ⅱ),检出限为5×10-9g/ml。用于维生素B12中钴的测定,获得满意的分析结果。  相似文献   

11.
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.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

13.
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。  相似文献   

14.
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.  相似文献   

15.
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-  相似文献   

16.
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-  相似文献   

17.
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  相似文献   

18.
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  相似文献   

19.
<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  相似文献   

20.
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