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钙指示剂分光光度法测定水中的钙 总被引:2,自引:0,他引:2
研究了钙指示剂 (Kalces)与钙作用的显色体系 ,试验了影响该显色体系的灵敏度和稳定性的各项因素 ,确定了最佳操作条件。试验表明 ,在pH为 5 .2的乙酸 -乙酸钠缓冲介质中 ,钙指示剂与钙生成蓝色 1∶1的配合物 ,λmax=6 2 0nm ,体系表观摩尔吸光系数ε =1.33× 10 4 L/ (mol·cm) ,在此波长及最佳操作条件下 ,钙含量在 0~ 1.6mg/L质量浓度范围内符合比尔定律。在试验了 19种常见共存离子干扰的基础上对 6种水样的钙度进行测定 ,回收率在 96 .5 %~ 10 3%之间 ,结果满意 相似文献
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以除钙工艺前后的粉煤灰溶出液作为分析试液,溶液中的铁、铝、钛、铜、锰等干扰元素不需要分离,在酸性溶液中用三乙醇胺溶液进行掩蔽消除干扰。以酸性铬蓝K-萘酚绿B作指示剂,采用EDTA络合滴定法测定除钙前溶液中钙含量。在测定除钙后溶液中的钙含量时,以钙黄绿素-百里酚酞作为指示剂,采用EGTA络合滴定法测定钙含量。使用这两种方法对除钙前后的钙进行了多次平行测定,两种测定方法测定结果的相对标准偏差在0.95%~2.84%,加标回收率在98.19%~102.66%。 相似文献
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简述了钙指示剂的结构、变色原理及与Ca2+的作用原理,论述了钙指示剂与EDTA的反应过程、干扰钙指示剂发挥作用的物质及pH值对钙指示剂的影响。 相似文献
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在pH为10的氨-氯化铵缓冲溶液中,以紫脲酸铵为指示剂,于505nm波长处用EGTA(EthyleneGlycol-bis-(2-Aminoethylether)-N,N,N’,N’-TetraaceticAcid,乙二醇双(2-氨基乙基醚)四乙酸)标准溶液光度滴定苦土试液中的钙,其变异系数小于4%,加标回收率为99.5~100.8%。 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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D. G. Gordeev L. F. Gudarenko M. V. Zhernokletov V. G. Kudel’kin M. A. Mochalov 《Combustion, Explosion, and Shock Waves》2008,44(2):177-189
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation
of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from
the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008. 相似文献
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Jorge Marcelo Romero Soledad Bustillo Hugo Enrique Ramirez Maisuls Nelly Lidia Jorge Manuel Eduardo Gómez Vara Eduardo Alberto Castro Alicia H. Jubert 《International journal of molecular sciences》2007,8(7):688-694
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out. 相似文献
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A perturbation viscometer is a differential capillary viscometer that measures the logarithmic viscosity gradient of the viscosity-composition curve for gas mixtures. Measurements are made at different gas mixture compositions. Integration of the logarithmic viscosity gradients measured over the full composition range gives the mixture viscosity relative to the viscosity of one of the pure components of the gas mixture. This method is attractive because, for measurements of equal precision, integration of the gradients is potentially an order of magnitude more precise than measurement of the viscosities directly. It can also work at high and low temperatures and perhaps high pressures.The perturbation viscometer has been used to make measurements on ideal gas mixtures at ambient and elevated temperatures. The situation is more complicated when the gas mixtures are non-ideal. Extra effects due to density differences, molar volume change on mixing and differential thermal expansion may be measured in addition to the desired viscosity change producing systematic errors in the results. Thus, a more sophisticated apparatus is required. The standard perturbation viscometer has been modified to separate out the extra effects to permit measurement of the true change in viscosity. In addition, the theoretical operation of the modified apparatus has been revised to account for the design changes to permit calculation of the viscosity-composition profiles from the results.The apparatus has been tested using helium-HFC-125 mixtures and two new viscosity-composition profiles are presented for these mixtures at 23 and . Internal consistency tests have been used to confirm that the data produced are of high quality with an estimated uncertainty in the viscosity ratio data at of 0.9% and at of 1.5%. 相似文献
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塔设备改造选型的分析 总被引:2,自引:0,他引:2
就当前扩产增容中塔设备设计和改造时板式塔和填料塔的选型问题加以分析。在评述目前国内常用的几种塔板和新型填料之后,着重介绍一种新型塔板(导向梯形浮阀塔板)和一种新型填料(波环填料——乾隆帕克)。 相似文献