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本系统地研究了硫代苹果在络合滴定中的掩蔽性能,发现它在pH1.5~10可作为Sn^4+、Sb^3+、Tb^3+、Bi^3+、Cu^2+、Hg^2+和Ag^+等的掩蔽剂(在pH2~3.5还可掩蔽Fe^3+)。掩蔽上述离子后,可在pH2.5~3用Th^4+回滴EDTA,在pH5~6用EDTA滴定Zn^2+或Yb^3+等,或在pH10用EDTA滴定Mg^2+、Ca^2+、Mg^2++Ca^2+和Mn^ 相似文献
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1—(5—溴—2—吡啶偶氮)—2—萘酚—6—磺酸作指示剂络合滴定连续测定铜和锌 总被引:9,自引:1,他引:9
对5-Br-PAN-S作指示剂络合滴定连续测定铜和锌进行了研究,在pH6.0的乙酸乙酸的钠介质中,以5-Br-PAN-S作指示剂,EDTA为滴定剂连续测定铜和锌,滴定终点颜色变化敏锐,准确度高,铜和锌量各在0~20mg范围内与EDTA用量成正比,铜,锌比例在1:10~10:1范围内相互无影响,方法用于合金中铜,锌的连续测定,结果满意。 相似文献
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络合滴定法测定低压流体输送用镀锌焊接钢管镀锌层重量 总被引:2,自引:0,他引:2
介绍了利用络合滴定法测定低压流体输送用镀锌焊风管镀锌层重量的方法,试样用稀硫酸溶解,在PH1.5 ̄2.0的弱酸性介质中,以磺基水杨酸钠为指标剂,用EDTA滴定铁,调PH为5.5,以PAN为指示剂,用EDTA滴定锌,由EDTA用量求出锌的重量,用GB/T3091-93方法比较,试验结果满意。 相似文献
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本文提出了一种电沉积光亮锡钴镜三元合金的新工艺,其溶液组成及操作条件为:Na3C6H5O7.2H2O100-150,Na2EDTA.2H2O20-30,SnCl2.2H2O15-20,CoSO4.7H2O25-35,ZnCl215-20g.L^-1;稳定剂WDZ-1 60-100,光亮剂WDZ-215-20mL.L^-1,pH=4-6,Dk=0.55。0A.dm^-2,T=5-35℃。在此条件下可 相似文献
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本文在pH5.5的乙酸-乙酸钠介质中,对以5-Br-PADAP作指示络合滴定法连续测定锌和铜进行了研究,对滴定的pH值及指示剂用进行了选择,试验了锌,铜不同配比的滴定结果,研究了共存离子的干扰。实验表明,用5-Br-PADAP作指示剂,EDTA作滴定剂连续和铜,滴定点颜色变化敏锐,准确度高,锌和铜均在0-20mg范围内与EDTA用量成正比,锌,铜比例在1:10-10:1范围内相互无影响。方法用于标 相似文献
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不经分离,高敏,连续光度滴定混合物中钕和铁 总被引:3,自引:0,他引:3
提出以Fe(3+)(Nd(3+)-CAS-CPB-C2H5OH作为不经分离、高敏、连续光度配合滴定混合物中Fe(3+)和Nd(3+)的多元胶束配合指示体系。滴定Fe(3+)和Nd(3+)的适宜pH分别为2.3~3.2和6.0~8.6。用EDTA目视滴定Fe(3+)时,终点处由蓝紫变粉红色,对比度大(Δλ=130nm)、灵敏度高(配合物摩尔吸光系数ε(630)=1.14×105L·cm(-1)·mol(-1),至少可检测0.4μg/mL,滴定线性范围为0~2.8μg/mL。线性相关系数为0.9994;目视滴定Nd(3+)时,终点处由绿色变橙黄,Δλ>180nm,ε(630)=7.6×104,至少可检测1μg/mL,滴定线性范围0~3.7μg/mL,线性相关系数0.9994。对于铁钕硼混合物样品则不经分离在630nm处连续光度滴定,可更精密、高敏、准确地确定终点,变异系数1.76%~2.86%,标准加入回收率96%~104%,且简便、快速。 相似文献
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本文提出了络合极谱双点滴定中置换滴定法的测定方法和定量公式,研究了以EDTA为络合剂,在HAc-NaAc缓冲溶液中,以乳酸置换与Sn^4+络合的EDTA,以CdCl2标准溶液为滴定剂测定Sn。对于5×10^-5mol的Sn,回收率达99.2%。应用该法于青铜样品中Sn的含量的测定,结果较为满意。 相似文献
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ICP-AES 法测定 RZnAl5RE 合金中的镧、铈、铁、铝、铅、镉 总被引:3,自引:2,他引:1
采用ICP-AES测定了RZnAl5RE合金中的La、Ce、F3、Al、Pb、CD元素含量。考察了基体及无机酸浓度对6种元素线强度的影响。选择了仪器工作条件,检出限在0.03~1.00μg/L之间,加标回收率为93%~108%,相对标准偏差小于12.68%(n=10)。 相似文献
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Gajavalli Kasi Mikaelian Georges Barrachin Marc Decreton Alexandre Fischer Evelyne Rogez Jacques Benigni Pierre 《Journal of Thermal Analysis and Calorimetry》2019,135(4):2209-2219
Journal of Thermal Analysis and Calorimetry - An Ag–Cd–In alloy is used as the control rod material in most pressurized water reactors. Despite this important application, the phase... 相似文献
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Three coordination architectures, {[Ag4(pbmb)4·(BF4)4](CH3OH)2·H2O}n (1), {[Cd2(pbmb)4](ClO4)4·(CH3OH)5}n (2), and [Cd4(pbmb)4·I8(CH3OH)2]n (3) (pbmb = 1-((2-(pyridin-2-yl)-1H-benzoimidazol-1-yl)methyl)-1H-benzotriazole), are built up from Ag(I)/Cd(II) salts and a flexible pyridyl-benzimidazole-based organic spacer. Single-crystal analysis shows that 1 and 2 have 1-D chains, while 3 displays a tetranuclear structure. All complexes exhibit different coordination geometries and properties, which can be attributed to the difference between the metal centers or anions. In the case of 1 in particular, the Ag?Ag interactions play a crucial role in the formation of a supramolecular architecture. The binuclear-based complex consists of a pair of Ag?Ag contacts (ca. 2.953 Å), and it exhibits intense triplet emission with large Stokes shift and high thermal stability. Compared to pbmb, 2 has excellent high-energy fluorescence properties, while 1 and 3 exhibit mainly low-energy emission. Therefore, it can be concluded that the heavy atom effect has a causative influence in enhancing the triplet state radiative rate, resulting in large Stokes’ shift of the complex. 相似文献
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浮选富集—原子吸收光谱法同时测定水中铜铅镉银 总被引:2,自引:0,他引:2
研究了浮选技术在富集水中铜铅镉银的应用,将这一技术与火焰原子吸收光谱法相结合,提高了灵敏度,操作简便.方法检出浓度铜为lμg·L~(-1),铅为10μg·L~(-1),镉为0.5μg·L~(-1),银为0.5μg·L~(-1),相对标准偏差和回收率均很满意. 相似文献
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A number of samples of sodium phosphate glasses doped with Cd/Co or Ag chlorides were prepared and characterized by X-ray diffraction, IR spectral, ion transport and DSC studies. It was found from DSC studies that the glass transition temperature (T
g) and crystallization temperature (T
c) values increased with the increasing concentrations of the dopants Cd/ or Co chlorides. However, the T
g and T
c values were found to decrease when the AgCl was taken as the dopant and the following sequence is observed: T
g(CoCl2)>T
g(CdCl2)> T
g(AgCl) T
c(CoCl2)>T
c(CdCl2)>T
c(AgCl) These results have been discussed and explained on the basis of changes in the structure of sodium phosphate glassy matrix by the addition of different cations as dopants.The authors are thankful to Prof. M. L. Srivastava, Head, Department of Chemistry, D. D. U. Gorakhpur University, Gorakhpur, and Prof. Suresh Chandra, Department of Physics, B. H. U. Varanasi for providing necessary laboratory facilities and help in carrying out the present work. The financial support from the Department of Science and Technology and University Grants Commission, New Delhi is also gratefully acknowledged. 相似文献