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选择水杨基荧光酮-乳化剂OP-盐酸为显色体系,应用双波长分光光度法扣除硫酸锌的基体干扰,不分离直接测定了湿法炼锌过程中硫酸锌净化液中的痕量锗。测定范围在0-40mg/L。本法应用于株洲冶炼厂锌净化液中锗的测定,结果与该厂长期的萃取-比色法结果相吻合,而测定速度较萃取-比色法至少提高了一倍。 相似文献
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β—羧乙基锗倍半氧化物中无机锗的示波极谱法测定 总被引:1,自引:0,他引:1
β-羧乙基锗倍半氧化物(Ge-132)因其有增强人体免疫功能和抗衰老等作用而被用于食品添加剂和某些化妆品中。在合成过程中若处理不当则会有较高含量的无机锗存在。无机锗对人体有毒害作用,故合成产品中无机锗的含量是衡量产品质量优劣的重要指标。若采用苯芴酮吸光光度法测定无机锗,有机锗有干扰。需萃取分离后测定,手续较繁。我们通过试验发现,β-羧乙基锗倍半氧化物在草酸-苏木精-V(Ⅳ)体系中示波极谱法测定无机锗时不产生干扰,无需分离有机锗。方法快速、简便。 相似文献
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锌与锗对小鼠抗氧化作用影响的实验研究 总被引:1,自引:0,他引:1
对240只小鼠的血清、肝脏、肌肉进行了锌和锗含量,抗化指标SOD活性、MDA含量测定。观察结果表明,微量元素锌与锗在小鼠血清中有一定的竞争作用。血清锌锗与肌肉、肝脏锌、锗及SOD有一定的相关性。由于锌和锗含量的变化,小鼠抗氧化作用受到了影响。当两者联合应用时,SOD活性有不同程度增加,MDA含量随之下降,提示了锌与锗在小鼠抗氧化方面有一定的协同作用。 相似文献
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本文对锗烟尘中锗浸出过程的动力学和反应机制进行了研究.结果表明,锗烟尘浸出符合不生成固体产物层的"未反应核缩减型"模型,动力学方程遵从1-2a/3-(1-a)1/3=kt.锗烟尘中锗浸出的表观活化能12.603kJ/mol,这表明锗烟尘中锗的浸出过程为边界层扩散所控制.在浸出时间3小时内,锗的浸出反应为2级反应.提高酸的浓度、温度、搅拌强度均可加速锌浸出速度,提高浸出率. 相似文献
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高含量锗物料中锗的滴定法测定 总被引:4,自引:0,他引:4
从碘酸钾容量法测定高含量锗物料中锗量的关键步骤蒸馏分离入手,分析了方法误差的原因,推出了一套设计合理、无泄漏、易于操作的蒸馏装置,使用该蒸馏装置蒸馏分离效果好,标准回收率高,测定结果精密高,具有推广价值。 相似文献
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Ge-132中的无机锗含量是一个重要的质量指标.它主要来自GeHCl3中的GeCl4,而无论哪种锗原料合成Ge-132,GeHCl3都是中间产物.与用金属Ge和GeO2制备Ge-132的工艺比较,用GeO2的盐酸溶液比用金属Ge在高温下与HCl气反应制备GeHCl3更利于降低Ge-132中残留的无机锗含量. 相似文献
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1871年,门捷列夫依据元素周期律预见了“类硅”(eka-silicon)的存在及其性质。1885年,德国分析化学家文克勒在对硫银锗矿进行分析时,意识到一种新元素的存在。至1886年2月6日,文克勒成功制取出金属单质,并将其命名为锗(Germanium)。在对锗元素的性质进行测定后,证实它正是门捷列夫所预见的“类硅”,从而证明了元素周期律的预见功能。20世纪20年代以后,锗同位素的发现使人们对锗元素有了新认识。总之,锗元素及其同位素的发现不仅是科学知识不断积累的结果,也是科学方法与科学思想相互融合的结晶。 相似文献
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4,5—二溴苯基荧光酮和十二烷基硫酸钠吸光光度法测定锗 总被引:2,自引:0,他引:2
用取代苯基荧光酮作为显色列的胶束增敏吸光光度法测定锗已有不少报道.形成的多元体系中,各种类型表面活性剂都有应用,但以阳离于表面活性剂为主,而阴离子及两性表面活性剂则极少报道.笔者通过试验发现,使用阴离子表面活性剂十二烷基硫酸钠(SDS)参与锗与4,5-二溴苯基荧光酮(DBPF)的显色反应.不仅具有较高灵敏度,而且具有很好选择性.低价金属离子及非金属离子均不干扰锗的测定.易产生干扰的高价金属离子的允许存在量均达数百微克以上,优于已有的光度法测定锗的所有体系.直接测定了煤样中微量锗,方法简便快速,获满意结果. 相似文献
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高锌试样中痕量锗的吸光光度法测定 总被引:1,自引:0,他引:1
建立了高锌试样中痕量锗的快速光度分析方法,显色条件为8×10~(-5)mol·L~(-1)SAF 0.8g·L~(-1)OP 2.4mol·L~(-1)盐酸,λ_(max)为510nm,锗浓度在0.05~5μg/25ml范围内符合比耳定律,摩尔吸光系数为1.3 ×10~5. 相似文献
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利用手持技术改进测定乙醇分子结构实验 总被引:1,自引:0,他引:1
利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。 相似文献
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V. I. Bol'shakova L. I. Demenkova É. N. Shmidt V. A. Pentegova 《Chemistry of Natural Compounds》1989,24(6):691-694
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988. 相似文献
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Mustafa R. Ibrahim Zacharia A. Fataftah Paul von Ragu Schleyer Peter D. Stout 《Journal of computational chemistry》1987,8(8):1131-1138
Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases. 相似文献
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V. I. Bol'shakova L. I. Demenkova É. N. Shmidt V. A. Pentegova 《Chemistry of Natural Compounds》1988,24(6):691-694
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae. 相似文献
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Effect of the Method of Modification of Zeolite X on Selectivity of Catalytic Methylation of Toluene
Voloshyna Yu. G. Pertko O. P. Patrylak L. K. 《Theoretical and Experimental Chemistry》2019,54(6):395-400
Theoretical and Experimental Chemistry - The effect of the method of modification of catalysts based on zeolite X by cesium and magnesium cations (ion exchange and impregnation) on the selectivity... 相似文献