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钪与偶氮氯膦Ⅲ的显色反应 总被引:1,自引:0,他引:1
钪与偶氮氯膦Ⅲ显色反应表明显色体系的吸收光谱有三个吸收峰,分别位于623、697和770nm处,并有相应的γ、α和β型配合物生成。初步探讨了该反应的特殊性。 相似文献
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对乙酰是偶氮氯膦(CPA-PA)是近年来新合成的用于稀土总量测定的良好显色剂.本文研究了锆与CPA-pA的显色体系,试验结果表明,在0.2mol·L~(-1)HCl酸度下,Triton X-100和乙醇联合使用,Zr-CPA-pA配合物表观摩尔吸光系数为2.60×10~(-4),在Zr 0~25μg/25ml范围内符合比耳定律.此法用于硅酸盐材料中锆的测定,速度快,分析结果令人满意. 相似文献
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间磺酸基偶氮氯膦与Cr(Ⅲ)显色反应研究及应用 总被引:4,自引:1,他引:3
文中报道了肺心30病列和健康对照16例的红细胞变形能力与红细胞膜收缩蛋白二聚体和四聚体的相对含量。结果表明,肺心病Ⅰ、Ⅱ型呼吸衰竭病人红细胞变形指数和Sp-D,Sp-T相对含量与对照组均有显著差异,且肺心病病人的DI与Sp-D/Sp-T比值呈显著负相关。提示膜收缩蛋白的异常,可能是导致肺心病人红细胞胞变形能力降低的重要因素之一。 相似文献
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钯(Ⅱ)-偶氮氯膦pA显色反应及其应用 总被引:8,自引:0,他引:8
测定微量钯的有机显色剂种类较多.其中选择性和灵敏度较好的是杂环偶氮化合物,但所有钯的显色反应无例外地需要加热,或需有机溶剂萃取.偶氮氯磷类试剂测定钯亦有报道.本文采用偶氮氯膦pA[2-(4氯-2-膦酸基苯偶氮)-7-(4-乙酰基苯偶氮)-1,8-二羟基-3,6-萘二磺酸]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(?)_(650)4.5×10L·mol~(-1)·cm~(-1),钯含量在0.0~1.0 mg/L范围内符合比耳定律.建立了测定微量钯的分光光度分析法.本法具有简便快速,室温下在水相中直接测定微量钯的优点.应用于催化剂中钯含量的测定,结果令人满意. 相似文献
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《Analytical letters》2012,45(4):799-809
ABSTRACT A novel spectrophotometric method based on amino G acid chlorophosphonazo (AGCPA) has been developed for measuring calcium in human serum and cerebrospinal fluids. The effects of experimental factors including pH, reagent concentrations, and interfering species on calcium determinations were investigated. In a neutral reaction media of pH 7.0, AGCPA reacts rapidly with calcium to form a stable and greenish blue complex, whose absorption maximum is at 670 nm. The molar absorptivity (?) of the complex is 7.2x104 1 mol?1cm?1, and the molar ratio of calcium to AGCPA in the complex is found to be 1:2. Beer's law is obeyed over the range 0.02-0.8 μg ml?1 of calcium. No interferences were observed from the commonly coexisting species present in serum and cerebrospinal fluids. Compared to the reported and currently often used methods based on o-cresolphthalein complexone, arsenazo III and methylthymol blue, the proposed method in this work provides better analytical characteristics such as high sensitivity, good selectivity and neutral reaction media. In addition, the present method is simple and can be applied to the direct determination of calcium in human serum and cerebrospinal fluid samples with satisfactory results. 相似文献
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硝基苯并噻唑重氮氨基偶氮苯与汞的显色反应研究 总被引:5,自引:0,他引:5
报道了新试剂硝基苯并噻唑重氮氨基偶氮苯 ( NBTDAA)与汞的显色反应。结果表明 ,在非离子表面活性剂 Triton X-1 0 0存在下 ,p H为 9.5~ 1 0 .0的 Na2 B4O7-Na OH缓冲体系中 ,汞与该试剂能形成 1∶ 4的络合物 ,其最大吸收波长为 51 5nm ,表观摩尔吸光系数为 1 .3 5× 1 0 5 L· mol- 1 · cm- 1 ,线性范围 0~ 1 2μg/ 2 5m L。用拟定的方法测定了废水中的汞 ,结果满意。 相似文献
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The complexes formed by calcium ion and 12 common amino acids were investigated systematically in the gas phase at the level of MP2/6-311++G(d,p)//MP2/6-3 1G(d,p).The results show that the salt-bridge structure is the most preferred motif for Ca2+ binding aliphatic amino acids without heteroatom in the side chain,while charge-solvated(CS) structure is the most preferred motif for Ca2+ binding other amino acids except for glutamine and lysine.IR spectra of Gln-Ca2+ and Asn-Ca2+ complexes were calculated and compared well with the available experiments.From the study in aqueous solution,the bidentate salt-bridge structure was determined to be the most favorable for all the twenty kinds of amino acids to chelate Ca2+ to both the oxygen atoms of the negatively carboxylate group in the backbone. 相似文献
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碱土金属与多卤代偶氮氯膦类试剂显色反应的研究 总被引:1,自引:0,他引:1
近年来合成的多卤代偶氮氯膦类试剂有希望成为一类有效的碱土金属显色剂。本文研究了此类试剂与钙、锶、钡所生成配合物的吸收光谱、显色酸度、选择性、灵敏度和配合物的组成,以及试剂结构与性能的关系等。说明了不同取代助色基对显色反应各方面的影响。通过研究筛选出了较好的碱土显色剂,这几种试剂的结构如下: 相似文献
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双噻唑偶氮试剂BDTADAB与钯显色反应的研究和应用 总被引:3,自引:0,他引:3
研究了新的双噻唑偶氟试剂2,6-二偶氮(4,4′-(双间苯二胺)-苯骈(1,2-d,4,5-d)二噻唑(BDTADAB)与钯的显色反应,在5.8mol/L硫酸介质中,钯与试剂生成的络合物最大吸收波长为604nm,表观摩尔吸收系数为4.2×10^4L.mol^-1.cm^-1钯在0~16μg/25mL范围内符合比尔定律,常见金属离子及铂,金等贵金属离子均不干扰钯的测定,该方法具有简便,快速,选择性高 相似文献
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MA Hui-Min 《高等学校化学学报》1999,20(Z1):298
Calcium ions play a key role in a number of physiological processes including blood coagulation, secretion, muscular contraction and intercellular communication. Hence, the monitoring of calcium in body fluids is of great importance in the diagnosis and prevention of various diseases. There have been a lot of methods dealing with the measurements of calcium in human serum and cerebrospinal fluids, among which atomic absorption spectrometry is considered to be the best one, but spectrophotometric methods are more often used because of their simplicity and low cost. 相似文献