期刊目錄列表 - 11~20期(1966-1975) - 第十六期 (1971)

偶氮砷三號(Arsenazo-Ⅲ)為比色劑之分光光度定量各水試樣中微克釷 作者:許明星

摘要:

藉偶氮砷三號(Arsenazo-III)為比色劑,分光光度法定量各水試樣中微克釷,業經研究。
一、當釷對諸元素之比率不超過:比100(正一價,正二價陽離子);1比30(稀土和正三價陽離子);1比2(UO2+2,Zr+4)時,分光光度法能直接定量如後:加1.5ml 10%抗壞血病酸(Ascorbic acid)溶液和1.5ml 10%氯化氫(合)羥胺(Hydroxylamine hydrochloride)溶液入試樣中,煮沸,待冷卻至23~25℃,混合0.5ml 0.1% Arsenazo-III比色劑溶液,用水稀釋至10ml,調至pH 0.5,由紅色濾光器,在665mμ測定之。每含04~28微Berr克釷之全程系試樣,符合律。
二、試樣在任何超過上述量之陽離子或1 ml 0.1M之任一F-,SO4-2,SiO3-2,NO3-之陰離子存在下,得以包括加1m1之62%HCIO4蒸煙和Fe(OH)3,為載體沈澱二次之手續(a)有效分離而測定之。至於大量之UO3+2,U+4,Zr+4,Ti+4,與其選手續(a)毋寧採用CaC2O4為載體之手續(b)。
上述諸手續測定釷誤差,均少於2.5%。

《詳全文》

Journal directory listing - Volume 11-20 (1966-1975) - Volume 16 (1971)

Spectrophotometric Determination of Microgram Quantities of Thorium in Various Aqueous Samples using Arsenazo-III Author: Ming-Sing Hsu

Abstract:

The spectrophotometric determination of microgram quantities of thorium in various aqueous samples using Arsenazo-III as reagent was studied.
I. When the ratio of thorium to elements is not in excess of: 1 to 100(1+,2+ charged cations); 1 to 30(rare earth and 3+ charged cations); 1 to 2 (UO2+2,Zr+4), they can be determined directly by spectrophotometry as follows: Add 1.5ml of 10% solu'n of ascorbic acid and 1.5ml of 10% solu'n of hydroxylamine hydrochloride to the sample, boil, cool to 23-25℃, mix with 0.5ml of 0.1% solu'n of Arsenazo-III reagent, dil, to 10ml with water, adjust to pII 0.5, and measure at 665mμ with a red filter. The system conforms Beer's law over the range of 0.4-28 r Th per sample.
II. In the presence of the quantites of any cations exceed the above statement or 1 ml 0.1M of any anions of F-, SO4-2, NO3- , SiO3-2, the samples can be separated and determined effectively by procedure (a) which consists of adding 1 ml of 62% HCIO4 to be fumed and precipitating twice with Fe(OH)3 as carrier. As for great quantities of UO3+2,U+4,Zr+4,Ti+4,procedure (b) using CaC2O4 as carrier is preferred to procedure (a)
The estn. Error in Th is less than 2.5% in all the above procedures.