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101.
Thermogravimetric analysis is used to determine the amounts of Mg(OH)2 and Mg(CH3COO)2in a mixture thereof. The application and suitability of different analysis methods are discussed. In the first method the
mass losses in the temperature ranges as indicated by the decomposition of the pure compounds were used. Results obtained
using these temperature ranges were unusable. The percentage mass losses due to the decomposition of Mg(OH)2 and Mg(CH3COO)2 were then determined in a second method using the minimum in the derivative mass vs. temperature curves. The results obtained
by this method compared well with the actual values for mixtures containing more than 15% magnesium acetate. The third method
employed the total experimental mass loss of both decomposition reactions. The results obtained using this method compared
well to the actual values, giving a R
2 value of more than 0.99. This method of using the total mass losses can however only be used for binary mixtures that consist
only of magnesium hydroxide and magnesium acetate.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
102.
Francisco García-Montelongo María J. Sánchez Miguel A. Rodríguez 《Mikrochimica acta》1989,98(4-6):259-265
A spectrophotometric method for cyanide based on its inhibition of the colour formation reaction between nickel(II) and 3-(4,5-dimethyl-2-thiazolylazo)-2,6-dihydroxybenzoic acid has been developed, and allows the determination of down to 0.1 g of cyanide. Most of the interferences can be avoided by displacement of the hydrogen cyanide using an arsine generator. 相似文献
103.
光谱电化学法测定水果中抗坏血酸的研究 总被引:7,自引:2,他引:7
本文采用平行入射式光谱电化学装置,对水果中的抗坏血酸进行测定并寻找了最佳的测定条件。方法简便快捷,可消除背景干扰。线性范围1.0×10^-5-1.0×10^-4mol/L,检测下降为4.0×10^-6mol/L,回收率高,结果满意。 相似文献
104.
对抚州地区秀茶场产的茶叶进行了微量元素测定,提供了五种茶的微量元素谱,同时还对比了秀谷茶场产茶和英德红茶中的微量元素含量的差异。 相似文献
105.
硫酸颜色反应用于荧光法测定利血平研究 总被引:6,自引:1,他引:6
提出了硫酸颜色反应用于利血平的荧光分析新方法。利用血平与浓硫酸反应,生成强荧光物质,所得产物的荧光强度与利血平的浓度在0-0.6μg/mL范围内有良好的线性关系。检测限为0.2ng/mL。本法可直接用于尿液中利血平的定量分析,回收率为82.5%-84.2%。 相似文献
106.
A series of approaches have been assayed for FTIR determination of Mancozeb in several solid commercial fungicides using different calibration strategies. The simplest procedure was based on the use of the ratio between the absorbance of a characteristic band of Mancozeb and that of a KSCN internal standard measured in the FTIR spectra obtained from KBr pellets. It was employed the quotient between peak height absorbance values at 1525 cm−1 for Mancozeb and 2070 cm−1 for KSCN. In these conditions a precision as relative standard deviation (RSD) of 0.6% and a relative accuracy error of 0.8% (w/w) were found. For complex formulations, containing other compounds with characteristic absorption bands at different wavenumbers than Mancozeb, one of them was used as internal reference being employed the standard addition approach. In this case, the Mancozeb bands at 1525 cm−1 or at 1289 cm−1 were employed, being used the ferrocyanide band at 2075 cm−1 as internal reference. RSD values between 0.7-1.4% and a relative accuracy error of 3% (w/w) were found. A third strategy was based on the use of partial least squares (PLS) calibration. A reference set was prepared mixing Mancozeb, Kaolin, Cymoxanil and KBr, being predicted the Mancozeb concentration in pesticide formulations by using the quotient between absorbance bands of Mancozeb and those of Cymoxanil. In these conditions a relative accuracy error of 0.6% (w/w) and a relative standard deviation of 1.3% were found. 相似文献
107.
用X-射线荧光光谱法,测定了387例内蒙古牧区蒙古族、汉族成人和儿童的发中铜(Cu)、锌(Zn)、铁(Fe)、锶(St)及钙(Ca)的含量,对同一地区蒙、汉族成人间,成人及儿童间发中五种元素含量进行了比较分析。结果表明:蒙汉族成人发中Cu,Zn、Fe含量不受种族及饮食习惯的影响,其含量无显著性差异;蒙汉族成人发中Sr和Ca含量存在着相平行的显著差异;牧区儿童发Zn含量与牧区成人发Zn含量差异无显著性意义,提示牧区儿童不缺Zn,可能与多动物性食物有关;牧区儿童发中Cu、Fe、Sr、Ca均显著低于牧区成人、可能与儿童发育旺盛和Zn摄入量高对Cu、Fe吸收发生抑制有关。 相似文献
108.
报道了以235名健康小儿的血清锌、铜正常参考值及铜/锌比值作依据,对538名本地区集体儿童进行了调查.对240例不同病种患儿的血清锌、铜含量测定,并进行了分析;对G6PD、GSH-PX、AKP醇活性与微量元素含量的关系进行了相关性比较;对微量元素锌缺乏症的患儿进行了临床治疗观察;对微量元素缺乏症的防治进行了讨论. 相似文献
109.
The crystal structure of new compound Ba3BPO7 was determined by ab initio method from high-resolution conventional X-ray powder diffraction data. The Rietveld refinement converged to Rp=5.92%, Rwp=8.87%, Rexp=5.00% with the following details: Hexagonal, space group P63mc, a=5.4898 (1) Å, c=14.7551(1) Å, Z=2. The basic unit of the structure is the [BaO10]-[BO3]-[PO4] polar polyhedra-chain composed of Ba1-B-P-O cluster. These chains, running along c-axis, stack in a HCP mode to build the whole structure with triangular prism channels. The channels are parallel to c-axis too, in which Ba2 and Ba3 are located. 相似文献
110.
A new rapid and accurate method for the spectrophotometric microdetermination of Cu(II) and Pd(II) using some 1,3,5-triphenylformazans (I) is given. The optimum conditions for the formation of the complexes are extensively investigated. The ligands form 1:1 and 1:2 (M:L) complexes with Cu and Pd ions, Beer's law is obeyed up to 3.8 and 6.5 ppm Cu and Pd respectively. The influence of foreign ions is investigated. The ligands were used successfully as indicators in spectrophotometric titration of Cu and Pd ions with EDTA and CDTA. 相似文献