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1.
研究了pH为 5 0的醋酸 醋酸钠介质中存在大量锌时 ,镉和钴在丁二酮肟 柠檬酸钠 氯化铵体系中的络合物吸附波 .结果表明 ,镉、钴峰电位分别为 - 0 79V和 - 0 93V ,线性范围分别为 0 0 0 5~ 5mg·L- 1 和 0 0 0 0 1~ 0 1mg·L- 1 ,检测限分别为 4 0× 1 0 - 8mol·L- 1 和 8 1× 1 0 - 1 0 mol·L- 1 .该方法具有不经预处理可直接用于锌电解液中微量镉、钴同时测定的优点 .分析了电活性络合物的组成、极谱波性质和电极过程机理 .镉、钴与丁二酮肟 (DMG)的络合比均为 1∶2 ,Cd(DMG) 2 和Co(DMG) 2 络合物均表现出强的吸附特性 ,且前者吸附性更强 ,峰电流主要由络合物中心离子Cd(Ⅱ )和Co(Ⅱ )还原为Cd和Co产生 ,极谱波均为络合物吸附波  相似文献   

2.
Fe(Ⅲ)-茜素红-PVPK-30体系分光光度法测定微量铁   总被引:2,自引:0,他引:2       下载免费PDF全文
唐宁莉 《广西科学》2003,10(4):282-283,295
研究 p H值为 4 .5的 NH4 Ac- HAc缓冲液中 ,在表面活性剂 PVPK- 30存在下 ,铁 ( )与茜素红生成可溶性有色络合物的显色反应条件。络合物最大吸收波长在 6 0 0 nm,表观摩尔吸光系数 ε6 0 0 =2 .93× 10 4 L.mol- 1 .cm- 1 ,铁的浓度在 0~ 1mg/ L范围内符合比耳定律。把拟定的分析方法用于发样和水样中微量铁的测定 ,获得满意结果  相似文献   

3.
DIPF光度法测定食品和水样中微量铜的研究   总被引:1,自引:0,他引:1  
研究了新试剂二碘苯基荧光酮(DIPF)与铜的显色反应,在pH=5.4 盐酸-六次甲基四铵缓冲介质中,溴化十六烷基吡啶(CPB)存在下,DIPF与铜反应生成31红色络合物,λma×=560 nm, =8.04×l04L·mol-1·cm-1.铜含量在0~15ug/25mL内符合比尔定律,方法用于食品和水样中微量铜的测定,结果令人满意.  相似文献   

4.
研究了钯 (Ⅱ )与DBM偶氮氯膦显色反应的条件及应用 ,据此显色反应建立了测定微量钯的分光光度分析法 .DBM偶氮氯膦与钯离子在常温下于水相中形成蓝色络合物 ,其表观摩尔吸光系数 ε62 0=4.47×10 4L·mol-1·cm-1,钯含量在 0 .2~ 1.2 μg·mL-1范围内符合朗伯比尔定律  相似文献   

5.
杨水平 《江西科学》2001,19(4):244-246
研究了哌啶荒酸哌啶 (PDPC)与Cu(Ⅱ )最佳显色反应的条件 ,在pH =8.5的条件下 ,Cu(Ⅱ )与PDPC形成稳定的黄棕色络合物 ,络合物组成比为M∶R =1∶2 ,最大吸收波长λmax=4 40nm ,表观摩尔吸光系数ε=2 .86×1 0 4 L·mol- 1·cm- 1。该体系显色速度快 ,稳定性好 ,并有较好的选择性 ,应用拟定方法测定合成水样中Cu(Ⅱ )含量 ,结果满意。  相似文献   

6.
研究了氨 -氯化铵缓冲溶液中 ,铝、氟和 1.5-二 ( 2 -羟基 - 5-磺基苯基 ) - 3-氰基甲月替(DSPCF)的显色反应 .提出一个简便、快速的测定微量铝的分光光度法 .络合物的表观摩尔吸光系数为 3.51× 10 4 L·mol- 1·cm- 1.最大吸收波长为 610nm .室温下 ,显色反应在 10min内完成 .有色络合物稳定时间至少 6h .含铝 0~ 0 .4 8μg/mL范围符合比耳定律 .该法用于铅精矿中微量铝的测定 ,获得了满意的结果 .图 1,表 1,参 5.  相似文献   

7.
5,7—二溴[杯(4)芳烃偶氮]氨基喹啉光度法测定金   总被引:7,自引:0,他引:7  
研究了新试剂5,7-二溴[杯(4)芳烃偶氮]氨基喹啉(DBCAQ)与金的显色反应.在碱性介质中,在乳化剂-OP存在下,DBCAQ与金发生显色反应,生成1∶1稳定络合物,λmax=670nm,ε=2.62×10  相似文献   

8.
研究了哌啶荒酸哌啶(PDPC)与Mn(Ⅱ)最佳显色反应的条件,确定在pH=7.0的条件下,Mn(Ⅱ)与PDPC形成棕红色络合物,络合物组成比1∶1,可见光区最大吸收波长λmax=498nm,表观摩尔吸光系数ε=1.02×104L·mol-1·cm-1.应用拟定方法测定合成水样中Mn(Ⅱ)含量,结果满意.  相似文献   

9.
在非离子表面活性剂吐温-80存在下,研究了DBON-PF与Ge(Ⅳ)的显色反应,试验表明,在磷酸介质中,Ge(Ⅳ)与DBON-PF形成1∶2的红色络合物,该络合物的最大吸收波长为542nm,其表观摩尔吸光系数为1 23×105L·mol-1·cm-1,锗量在0~7g 25mL时符合比耳定律.用Ge(Ⅳ)-DBON-PF-吐温-80体系测定锗,很多离子不干扰测定.方法灵敏度高,选择性好,有色络合物稳定48h以上,直接用于煤中微量锗的测定,获得了满意的结果.  相似文献   

10.
基于聚丙烯酰胺(PAM)作为增稳剂时,铝与桑色素(Morin)之间的显色反应,提出了一种简便、快速、高灵敏测定痕量铝的光度法.铬合物组成比为A1∶Morin=1∶2,表观摩尔吸光系数ε408=6.3×107Lmol-1cm-1.铝浓度在0.04~0.28ng/mg范围内服从比尔定律,检测限4.0×10-10g/L发现PAM和Morin之间可形成另一种络合物并能用于PAM的测定,该络合物在350nm处的吸收峰强度与PAM浓度在0.02~0.1mg/L范围内成正比,检出限2.0×10-7g/L.所提出的方法用于水样中AL和PAM的不经分离测定,结果满意.  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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