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1.
根据AI 3 对KIO4氧化次甲基蓝褪色的催化行为,建立了测定痕量铝的催化动力学分析法,本法线性测定范围为0~720μg/L,检测限为1.1×10-8g/L,除Fe 3 外其余离子不影响测定,Fe 3 的干扰可用铜铁试剂-氯仿溶液萃取除去,利用本法测定水样中的铝含量,结果满意.  相似文献   

2.
催化氯酸钾氧化灿烂绿褪色光度法同时测定痕量铜和铝   总被引:4,自引:0,他引:4  
基于加热和KHC6H4(COO)2-NaOH (PH=5.00)缓冲溶液存在下,铜、铝催化氯酸钾氧化灿烂绿的褪色反应,建立了催化光度同时测定痕量铜和铝的新方法。本法测定铜、铝的线性范围分别为0.04~0.40μg/L和0.40~2.0μg/L;检出限分别为3.6×10-12g/mL和1.2×10-11g/mL。方法简便、准确,并用于实际样品的测定。  相似文献   

3.
催化过氧化氢氧化钙黄绿素褪色光度法测定痕量铁   总被引:1,自引:0,他引:1  
基于Fe(Ⅲ)对过氧化氢氧化钙黄绿素的催化反应,建立了高灵敏测定痕量铁的新方法.本法线性测定范围为0.4~4ìg/L,检出限为1.4х10-10g/mL,线性回归方程为ΔA=-0.0033 0.03812CFe3 (ìg/L),相关系数r=0.9991.本法已用于人发、茶叶中铁含量的测定,结果满意.  相似文献   

4.
本文研究了Fe(Ⅲ)离子对H_2O_2氧化百里香酚蓝褪色反应的催化效应及其动力学条件,从而建立了痕量铁的催化光度法。本法测定范围为0-1.4μg/25cm~3,检出限为7.5×10~(-9)g/cm~3。具有较好的选择性和重现性,用该法测定了人发及水样中的痕量铁,结果令人满意。  相似文献   

5.
催化动力学光度法测定痕量铜--Cu(Ⅱ)-罗丹明B-H2O2体系   总被引:1,自引:0,他引:1  
陈志兵  张莉  王选 《皖西学院学报》2005,21(2):51-52,55
研究了在弱酸性介质中微量铜催化H2O2氧化罗丹明B褪色的指示反应,建立了催化动力学测定铜(Ⅱ)的新方法。方法检测限为1.5μg/L,测定的线性范围0-3.75μg/25ml,本法已用于人发样及水样中的痕量铜的测定。  相似文献   

6.
基于安乃近能将Fe3+还原为Fe2+,Fe2+与铁氰化钾生成可溶性普鲁士蓝,建立了用可见分光光度法间接测定安乃近的新方法.对反应时间和反应温度进行了优化,安乃近浓度在0.06~7.20μg/mL范围内具有良好的线性关系,线性回归方程为A=0.0218+0.2394 C(μg/mL),相关系数R=0.999.摩尔吸光系数ε=8.4×104 L/(mol·cm).检测限(3σ/k)为0.024μg/mL.按照本法对市售安乃近片进行了测定,并进行了回收率实验,平均回收率为100.8%,结果令人满意.  相似文献   

7.
以模拟染料废水甲基橙(MO)溶液为目标物,研究了Fe2+、Fe3+均相催化臭氧氧化及负载型铁氧化物非均相催化臭氧氧化对MO的去除特性,并探讨了在非均相催化剂活性炭负载Fe2O3(Fe2O3/AC)、活性氧化铝负载Fe2O3(Fe2O3/Al2O3)催化臭氧氧化体系中pH值、催化剂投加浓度、臭氧浓度、MO初始浓度等工艺参数的作用规律.结果表明,Fe2+、Fe3+、Fe2O3/AC、Fe2O3/Al2O3的加入均能提高MO的脱色率和COD去除率,且Fe2O3/AC、Fe2O3/Al2O3的催化效果更为显著;当Fe2O3/AC、Fe2O3/Al2O3的投加浓度为1.0 g/L,臭氧浓度为15.0 mg/L,MO初始浓度为25.0 mg/L、pH值为5.0时,30 min时Fe2O3/AC、Fe2O3/Al2O3催化臭氧体系降解MO的脱色率和COD去除率分别为89.26%、48.45%和80.34%、38.41%.  相似文献   

8.
研究了在盐酸介质中,利用钒(V)催化溴酸钾氧化乙基紫褪色反应,建立了催化光度法测定痕量钒的新方法。方法的线性范围为0.2~1.6μg/L,检出限量为0.2μg/L,钒的测定相对标准偏差为1.24%~2.78%。Mn~(2+)、Cu~(2+)、Fe~(2+)、Fe~(3+)、Cr~(3+)、Pb~(2+)的干扰为50倍,K~+、Na~+、Ca~(2+)、Mg~(3+)、Cl~-、I~-等100倍以上无明显干扰。本法可以直接用于水样测定。  相似文献   

9.
文章研究了在酸性介质中,间苯二酚能强烈阻抑Fe(II)催化H2O2氧化曙红Y的褪色反应,建立了测定间苯二酚的阻抑动力学荧光分析法的新方法.测定间苯二酚的线性范围为400.0~4.0μg/L,检出限为3.2μg/L,用于水样中间苯二酚的测定,结果满意。  相似文献   

10.
催化动力学光度法测定微量铜——Cu(Ⅱ)-甲基橙-H_2O_2体系   总被引:1,自引:0,他引:1  
研究了在弱酸性介质中微量铜催化 H2 O2 氧化甲基橙褪色的指示反应 ,探索了催化动力学测定铜 ( )的新方法 .该方法测定的线性范围 0 .0 5~ 3.5 μg/ 2 5 m L,本法已用于人发样及水样中的痕量铜的测定 .  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.
王慧 《科技信息》2008,(10):240-240
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.  相似文献   

14.
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.  相似文献   

15.
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   

16.
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   

17.
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.  相似文献   

18.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

19.
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   

20.
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   

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