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1.
在一定的酸度条件下,乙基紫与磷钼杂多酸所形成的离子缔合物于555nm处有一最大吸收,在此波长处试剂空白的吸收最小.基于这一事实,本文提出了直接测定痕量磷的流动注射分光光度法.方法灵敏度高,选择性好,水中常见离子不干扰痕量磷的测定,工作曲线的线性范围为0-400μg/l的磷,检测下限达0.7μg/l,以120h-1采样频率,对各种天然水样进行测定,回收率为98.2%-102.5%,变异系数为0.1%-4.5%.  相似文献   

2.
紫外双波长光度法可以消除苯酚和苯胺的相互干扰 ,实现水中酚类和苯胺类物质的同时测定 ,所采用的双波长对为 2 0 9.0~ 2 39.8nm和 2 30 .0~ 2 5 3.5nm ,水样的 pH值应控制在 6 .6± 0 .2。水中K ,Na ,Ca2 ,Mg2 ,Cl-和OH-的浓度低于 2 0 0mg/L时不干扰酚类与苯胺类物质的测定 ,油类物质的干扰可通过萃取法消除。紫外双波长光度法测定酚类物质的线性范围为 0~ 2 0mg/L ,检出极限为 0 .0 5mg/L ;测定苯胺类物质的线性范围为 0~ 12mg/L ,检出极限为 0 .0 0 7mg/L。实际水样的加标回收实验和合成水样分析结果表明 ,本方法的相对误差绝对值小于 4.93% ,且操作简便、测试准确 ,可满足微量酚类和苯胺类物质的测定要求  相似文献   

3.
用紫外双波长光度法同时测定水中酚类和苯胺类物质   总被引:5,自引:0,他引:5  
紫外双波长光度法可以消除苯酚和苯胺的相互干扰,实现水中酚类和苯胺类物质的同时测定,所采用的双波长对为209.0~239.8nm和230.0~253.5nm,水样的pH值应控制在6.6±0.2。水中K+,Na+,Ca2+,Mg2+,Cl-和OH-的浓度低于200mg/L时不干扰酚类与苯胺类物质的测定,油类物质的干扰可通过萃取法消除。紫外双波长光度法测定酚类物质的线性范围为0~20mg/L,检出极限为0.05mg/L;测定苯胺类物质的线性范围为0~12mg/L,检出极限为0.007mg/L。实际水样的加标回收实验和合成水样分析结果表明,本方法的相对误差绝对值小于4.93%,且操作简便、测试准确,可满足微量酚类和苯胺类物质的测定要求。  相似文献   

4.
采用二苯碳酰二肼离子浮选,石墨炉原子吸收光谱法,测定了天然水中痕量铬(Ⅵ).铬(Ⅲ)用氧化剂氧化后,同样测定.讨论了影响铬(Ⅵ)离子浮选的一些因素,考察了多种共存离子的干扰.用于测量含铬(Ⅵ)1.0μg/L的水样,相对标准偏差为1.9%(n=7).铬(Ⅵ)的标准加入回收率在98.5%~110%,适于环境水样中铬的价态分析.  相似文献   

5.
报道了用自行组装的流动注射化学发光分析仪,对茜素紫-乳化剂OP-H2O2-Ti(IV)化学发光新体系进行了研究.考察了测定钛的最佳条件,测定Ti(IV)的线性响应浓度为0.5×10-7~8.0×10-6g·ml-1,检测下限达50ng·ml-1,对2μg·ml-1(IV)进行了11次重复测定,其RSD为2.1%,对28种常见的阴阳离子进行了干扰实验,表明方法具有较好的选择性,用于水样中钛的分析,结果令人满意.  相似文献   

6.
本文研究了锰(II)催化高碘酸钾氧化二苯胺磺酸钠和苯胺盐酸盐显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锰(II)的新方法,反应在醋酸-醋酸钠缓冲溶液中进行,并以邻菲罗啉和草酸钠作为活化剂,本法测锰(II)的灵敏度为4.6×10^-10g/ml,线性范围是0.5-2.4ng/ml,并对铝合金,纯铝和天然水样中的痕量锰进行了测定,获得满意的结果。  相似文献   

7.
基于α,α'-联吡啶作活化剂,在硫酸介质中,Fe(Ⅲ)催化过氧化氢氧化甲基红褪色的指示性反应,采用固定反应时间法建立了一种灵敏度较高的测定痕量Fe(Ⅲ)的方法,其灵敏度为2.68×10-11μg/mL,线性范围为0~0.6μg/25mL,用于水样中痕量铁的测定,回收率为90%~106%,相对标准偏差为3.13%。  相似文献   

8.
低压离子色谱法测定水样中的F^—和Cl^—   总被引:1,自引:0,他引:1  
采用低压离子色谱法测定水样中的F-和Cl-,选择了最佳操作条件.测定结果表明该方法精密度好、回收率高、线性范围宽、检出限低,通过对比样品测定结果可靠,效果令人满意  相似文献   

9.
考察了观测高度为12.5mm时,镧基体对其他共存稀土杂质元素测定的干扰效应,同时采用本研究室提出的光谱干扰系数校正法和浓度干扰因子联合校正技术有效地校正了镧基体效应,准确测定了3种不同镧基体浓度场合共存的14种稀土元素,建立了高纯氧化镧ICP-AES无基体匹配定量分析方法,样品回收率多为90%~110%,RSD%<6%,该方法可用于纯度低于99.98%氧化镧样品的分析.  相似文献   

10.
采用二苯碳酰二肼离子浮选,石墨炉原子吸收光谱法,测定了天然水中痕量铬(Ⅵ)。铬(Ⅲ)用氧化剂氧化后,同样测定。讨论了影响铬(Ⅵ)离子浮选的一些因素,考察了多种共存离子的干扰。用于测量含铬(Ⅵ)1.0μg/L的水样,相对标准偏差为1.9%(n=7)。铬(Ⅵ)的标准加入回收率在98.5% ̄110%,适于环境水样中铬的价态分析。  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.
<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   

19.
20.
<正>"Journal of Jilin University(Science Edition)"is a comprehensive academic journal in the fields of science sponsored by Jilin University and administrated by the Ministry of Education of the Peoples Republic of China.The journal started publication in 1955.The original name at starting publication was"Journal of Natural Science of Northeast People University",which was changed into"Acta Scientiarum Naturalium Universitatis Jilinensis"in 1958 owing to the name change of the university.The present journal name has  相似文献   

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