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在pH为10的NH_3-NH_4Cl缓冲溶液中,以紫脲酸铵为指示剂,于505nm波长处用EGTA光度滴定苦土试液中钙,获得满意结果(CV<4%,加标回收率为99.5%~100.8%)。 相似文献
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用流动注射光度测定法实现了锌净化液中高含量锌的快速自动测定,方法简单,虽仅采用传统的EDTA和锌的配合反应,以二甲酚橙为指示剂,但借助在制的CPAC-Ⅲ型分析仪,达到了运用微量分析的手段进行常量分析的目的,方法直接应用于测定锌净化液样品,分析速度为每小时测定60个样品,结果令人满意。 相似文献
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用流通光度滴定法建立了测定多元络合物组成的快速方法。方法简单,仅用中心离子和配体各一个标准溶液。经测定几组络合物体系,实验结果与文献值完全一致。 相似文献
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非水光度滴定法测定钢中低碳 总被引:2,自引:0,他引:2
严恒太 《理化检验(化学分册)》1998,34(8):339-341
研究了非水滴定定碳法中非水吸收液的组成、指示剂的配比及滴定终点时溶液色泽的吸光度变化。结果表明,由乙醇、乙醇胺及不饱和多胺组成的非水体系对钢样燃烧时所释出的二氧化碳能最有效的吸收。试验选择了百里酚酞和茜素黄R的混合液为滴定指示剂,能给出敏锐的终点指示。在此基础上设计了一套非水定碳的自动分析装置。无论自动仪器或手工操作所得的分析结果都与标准值符合。方法应用于低含量碳的测定。 相似文献
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用具有流通池的分光光度计作测定装置,建立了由平衡移动法测定络合反应中质子释放数的新方法。方法简单、快速,仅用一个标准溶液,适于在变更pH值范围内金属离子不发生水解和没有其他副反应的体系。 相似文献
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A rapid, simple and accurate method for determining phosphorus photometrically in iron ores and related materials, obviating the use of perchloric acid, is described. The sample is fused with sodium peroxide in a zirconium crucible and the melt dissolved in hydrochloric acid. The molybdenum-blue complex is developed by the addition of ammonium molybdate and hydrazine sulphate and the absorbance is measured at 725 nm. The range of the method is from 0.005 to 1.0% P. A batch of 6 samples can be analysed in about 2 hr. 相似文献
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Summary A procedure for the rapid photometric determination of manganese in the range of 4–24 mg/50 ml, is based on the oxidation of manganese(II) to manganese(III) by excess potassium dichromate in a medium of 8.0 to 9.0 M phosphoric acid at room temperature. Interferences are few when compared to the methods currently available. The method can be successfully employed for the estimation of manganese in ores and alloys and the results obtained compare favourably with standard methods. The method is therefore recommended for adaption for rapid routine analysis.
Schnelle Methode zur photometrischen Bestimmung von Mangan in Erzen und Legierungen
Zusammenfassung Ein Verfahren zur raschen Bestimmung von Mangan im Bereich von 4–24 mg/50 ml wird beschrieben. Es beruht auf der quantitativen Oxydation von Mn(II) zu Mn(III) mit Dichromat in 8,0–9,0 M phosphorsaurer Lösung bei Raumtemperatur. Die Störmöglichkeiten sind geringer als bei sonst üblichen Methoden. Das Verfahren wurde mit Erfolg zur Manganbestimmung in Erzen und Legierungen angewendet und gute Übereinstimmung mit Standardmethoden erzielt. Es wird für die schnelle Routineanalyse empfohlen.相似文献
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李杰阳 《中国无机分析化学》2020,10(4):45-50
三氯化钛还原重铬酸钾滴定法测定低品位多金属矿石中全铁含量是一种常见的检测方法,其根据指示剂的颜色变化指示滴定终点,然后目测标准滴定溶液消耗的体积,计算分析结果。通过试样的测试,对分析结果精密度和准确度进行了考察,相对标准偏差RSD均小于1.000%,加标回收率为94.6~100.0%,可用于低品位多金属矿石中全铁含量在0.500%及以上的测定。 相似文献
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A new technique for the quick dissolution of iron ore, magnetite and sinter products has been developed. The sample is dissolved with thioglycollic acid and hydrochloric acid, the excess of thioglycollic acid is oxidized, and the iron is reduced in the silver reductor. 相似文献
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A direct photometric titration method has been developed for the determination of tellurium. Tellurium(IV) is titrated with potassium dichromate in 2-6M nitric acid (or 1-4M perchloric acid) at 380-430 nm (blue-violet filter). Selenium(IV) does not interfere. 相似文献
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Precise coulometric determination of iron in iron ores with electrogenerated manganese(III) fluoride
Iron in Mohr's salt, electrolytic iron and iron ores has been determined by precision coulometric titration with electrolytically generated manganese (III) fluoride, with biamperometric end-point detection. The titration curve indicated the irreversibility of the electrode reaction of manganese(III) fluoride. Total iron in several standard samples of iron ores was determined with standard deviations of about 0.012%. 相似文献
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A spectrophotometric titration of nickel in the presence of cobalt is described using disodium ethylene diaminc tetraacetic acid as a titrant The end-point was obtained by plotting the corrected absorbancy against ml of titrant added Nickel concentrations of 2.5 to 25 mg were determined in the presence of up to 8 mg of cobalt with an error of 1% or less depending upon the concentration of Versenate used A 0.03M and 0.1M versenate was used The effects of pH, concentrations of nickel And cobalt, accuracy of the method, presence of interfering elements, and limitations of the method are discussed. 相似文献
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Summary Gold in iron ores has been determined by means of its catalytic action on the oxidation of mercury(I) by cerium(IV). The calibration curve is linear over the range 3–30 ng/ml. Only iridium(IV), platinum(IV), palladium(II), ruthenium(III) and gallium(III) interfere seriously, though some interference is experienced from lead(II), iron(III), osmium(VIII) and indium(III).
Zusammenfassung Gold wurde in Eisenerzen auf Grund seiner katalytischen Wirkung auf die Oxydation von Quecksilber(II) durch Cer(IV) bestimmt. Die Eichkurve verläuft von 2 bis 30 ng/ml linear. Nur Iridium(IV), Platin(IV), Palladium(II), Ruthenium(III) und Gallium(III) stören ernstlich, während eine geringfügige Störung auch durch Blei(II), Eisen(III), Osmium(VIII) und Indium(III) beobachtet wurde.相似文献
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A mercury(II) solution containing copper ion can be titrated photometrically at pH 4.7 with triethylenetetramine solution (trien) after the addition of iminodiacetic acid (IDA) ; IDA causes a reversal of the effective formation constants of Hg-trien and Cu-trien and permits the titration. Copper-trien which absorbs at 580 mμ serves as the indicator for the titration. Mercury can be determined in presence of many other metals with an accuracy of about 1%; the main interferences are iron-(III), nickel, bismuth and chloride ion. 相似文献
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The flame emission of lanthanum at 560 mmu decreases linearly with phosphate concentration until a 1:1 molar ratio is reached, and then remains practically constant. Lanthanum can be titrated with phosphate, the equivalence point being detected from the change in emission intensity. Errors due to consumption of solution by the atomizer can be kept low by using short spraying times and low galvanometer damping. The average error is about -1% for 0.1M solutions and less than -5% for 0.01M. The method gives good results in the presence of titanium(III), zirconium, thorium and aluminium but cerium(III) and yttrium seriously interfere. 相似文献