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本文建立了流动注射二甲酚橙光度法测定镀锌纯化液中Zn ̄2+的自动分析方法。利用区域采样技术和调整管路参数自动完成对样品的上千倍稀释,确定了最佳分析条件并研究了干扰离子的影响及消除办法。所建方法仪器简单,分析速度为84次/小时,变异系数(Zn ̄2+16.0g/L,n=20)为1.O%,用于实际钝化液分析,相对误差小于±10%。 相似文献
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加速溶剂萃取/气质联用法测定城市污水处理厂污泥中的多环芳烃 总被引:2,自引:0,他引:2
根据污水处理厂污泥的特点,将样品进行冷冻脱水后,使用加速溶剂萃取仪进行其中的多环芳烃物质提取,再用弗罗里土等为填料自制的净化柱消除提取液的浑浊和乳化现象,最后采用自动蒸发浓缩工作站浓缩提取液的方法进行样品前处理。使提取液中的多环芳烃能够在气质联用仪上获得较好的测定效果。 相似文献
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环境样品中壬基酚及相关化合物分离富集与测定 总被引:5,自引:0,他引:5
对近20年来环境样品中壬基酚及其相关化合物分析方法的研究进展进行了综合评述,重点讨论了样品前处理方法、柱分离和测定技术。 相似文献
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建立了顶空气相色谱法同时测定生活饮用水中17种挥发性卤代烃的分析方法。样品采用自动顶空进样技术,经DB–5毛细管色谱柱(30 m×0.32 mm,0.25μm)分离后,用电子捕获检测器检测。优化样品保存条件为加入0.5 g抗坏血酸,冷藏避光保存。优化顶空条件:平衡温度为70℃,平衡时间为30 min,NaCl添加量为2.5 g。使用4-溴氟苯作为质控物质,保证测定结果的准确性。17种挥发性卤代烃的标准曲线相关系数均不小于0.998,方法检出限为0.003~2μg/L,平均回收率为85.7%~105.7%,测定结果的相对标准偏差为1.0%~5.6%(n=6)。该方法快速、灵敏度高、重现性好,适用于生活饮用水中17种挥发性卤代烃的同时测定。 相似文献
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提出了改良J-Grof法血清直接胆红素测定值的数学校正方法,该方法对胆红素标准血清和控制样品的分析结果与目前植十分一致,对样品的分析与自动生化分析仪的分析结果高度相关,为血清直接胆红素的准确测定提供一个可靠的方法。 相似文献
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闭杯闪点法测定氢化三丁基锡的闪点 总被引:1,自引:0,他引:1
使用MINIFLASH FLA全自动中温八杯闪点仪(闭杯闪点法)测定了氢化三丁基锡的闪点。探讨了诸多因素如样品的储存状态、点火次数、升温速率、大气压的校正、仪器保养方法等对闪点测定的影响。 相似文献
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中国科学院大连化学物理研究所电化学分析小组 《分析化学》1977,(6)
随着我国环保工作的迅速发展,痕量重金属(如铜、铅、镉、锌等)的分析日益需要。为了适应环保分析所提出的灵敏、简便和自动化等要求,我们研制了一种自动反向极谱仪,用于水及其他样品中痕量重金属的分析。反向极谱技术,又叫阳极溶出极谱技术,近十年来,已广泛运用于痕量重金属的测定。它的优点在于仪器设备简单,灵敏度高,但不足处是要大量使用汞或汞盐,以及操作烦琐,不便于自动化。如何发扬反向极谱技术之长,克其之 相似文献
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自动电位滴定法测定炼油工业污水中的氯离子 总被引:2,自引:1,他引:1
介绍自动电位滴定法测定炼油工业污水中氯离子含量。炼油工业污水样品经加热煮沸、双氧水氧化等预处理后,通过调节使其pH=2~6,以硝酸银标准溶液为滴定剂,在自动电位滴定仪上进行电位滴定。试验表明,本方法可以用来测定带色度的炼油工业污水样品,且对样品的酸碱度无苛刻要求,过量的双氧水不影响测定结果,不同浓度的标准样品其测定结果与其标称浓度无显著性差异。 相似文献
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Piétri N Gaudel-Siri A Couturier-Tamburelli I Pons JM Aycard JP 《The journal of physical chemistry. A》2005,109(10):2120-2126
IR spectroscopy is coupled with the matrix isolation technique to study the reaction of trimethylsilylketene with HCl. From 50 K trimethylsilylketene reacts with hydrogen chloride, leading to the cleavage of the Si-C bond and the formation of trimethylsilyl chloride and acetyl chloride, through intermediate trimethylsilylacetyl chloride which was identified. A reaction profile for this result is proposed based on a theoretical study carried out at the DFT level. 相似文献
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A technique for identifying the origin band of an electronic transition is described. The technique utilizes the increased linewidth of helium van der Waals complexes caused by vibrational predissociation when the molecular part of the complex is vibrationally excited. The method is applied to the visible spectrum of chromyl chloride, and we conclude that the d5 band of chromyl chloride is not a second electronic origin. 相似文献
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Low temperature fluorination technique is adopted for fluorination of the following sulphur compounds in freon-11 medium (1) Sulphur dioxide (2) Thionyl chloride (3) Sulphuryl chloride (4) Tetrasulphur tetra nitride and (5) Sulphur bromide. All the compounds undergo oxidative fluorination to give rise to sulphur-fluorine compounds except sulphuryl chloride which resists fluorination. Sulphuryl chloride thus behaves as a good solvent medium for fluorination of other reactive compounds like elemental sulphur. Details of the experimental procedures adopted and the identification of the products will be presented. 相似文献
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《Microchemical Journal》1987,35(2):201-205
The low-temperature plasma ashing technique was applied to organic materials containing sodium chloride and residual ash was analyzed for chloride using ion chromatography. Recovery of the chloride was approximately 50%, while 20–30% of the chloride had been converted to chlorate. The remaining fraction of the chloride could have been volatilized due to electron and ion bombardments onto the sample surface within the glow discharge region. Pretreatment of the sample by impregnating with potassium carbonate improved the recovery of the chloride to 90% with practically no production of chlorate. 相似文献
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Pranav Kumar Gutch Sharma Jitendra Shrivastava Alankar Jain Anurekha K. Ganesan 《Journal of Thermal Analysis and Calorimetry》2013,111(3):1953-1958
Pralidoxime chloride known as 2-PAM chloride is used as antidote for nerve agent’s poisoning. This study was undertaken to establish the compatibility of 2-PAM chloride with a number of commonly used excipients by using thermoanalytical technique viz., differential scanning calorimetry (DSC) and thermogravimetry/differential thermogravimetry (TG/DTG) used in pharmaceutical formulation. The TG and DSC both results demonstrated that polyvinyl alcohol, polyacrylamide, microcrestline cellulose, hydroxypropyl cellulose, cellulose acetate, ethyl cellulose found to be compatible with 2-PAM chloride and chosen for the preparation of antidote against chemical warfare agents. 相似文献
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《Analytical letters》2012,45(11):1015-1023
Abstract The methyl chloride concentration distribution in the atmosphere is of importance to the discussion of potential ozone destruction by chlorine-catalyzed reactions in the stratosphere. A gas chromatographic-mass spectrometric technique for rapid measurement of methyl chloride in air samples is described. The procedure provides both better sensitivity and better precision than previously reported determinations of methyl chloride in air. Some representative data are presented to illustrate the use of the method. 相似文献
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J. F. van Staden 《Fresenius' Journal of Analytical Chemistry》1991,340(7):415-418
Summary An automated on-line system for the determination of chloride in industrial effluents and plating bath solutions based on the concept of flow injection analysis is described. Samples with a very high chloride content up to 6 g/100 ml (60 g/l) are analysed by using an automated in-manifold double on-line dialysis technique. The sampling rate is 100 samples per hour. The method is suitable for the analysis of chloride with a relative standard deviation of better than 0.8%. The measurement is based on the red-coloured iron thiocyanate complex. 相似文献
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The electrophoretic mobilities of particles of polytetrafluoroethylene (PTFE), prepared by a dispersion polymerisation technique using a peroxyacid initiator, have been determined using a mass transport technique. Investigations were carried out as a function of sodium chloride concentration at pH 9 and as a function of pH in the presence of various salts, namely, sodium chloride, potassium nitrate and potassium thiocyanate. The particles were found to have a low surface charge density, consistent with the idea that sparsely distributed charged sites originated from initiator fragments leaving the major part of the surface in a hydrophobic condition. Below a pH of ca. 4.5 increases of mobility with decreasing pH were observed with chloride and thiocyanate as the anion. These were attributed to an anion adsorption process, dependent on thepKa of the surface groups, and a model for the process is described. 相似文献
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The room-temperature solid-state chemical reaction technique has been used to synthesize the silver nanoparticle-loaded semiconductor silver@silver chloride for the first time. It has the advantages of convenient operation, lower cost, less pollution, and mass production. This simple technique created a wide array of nanosized silver particles which had a strong surface plasmon resonance effect in the visible region, and built up an excellent composite structure of silver@silver chloride hybrid which exhibited high photocatalytic activity and stability towards decomposition of organic methyl orange under visible-light illumination. Moreover, this work achieved the control of composition of the silver@silver chloride composite simply by adjusting the feed ratio of reactants. It offers an alternative method for synthesising metal@semiconductor composites. 相似文献
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Switaj-Zawadka A Konieczka P Szczygelska-Tao J Biernat JF Namieśnik J 《Journal of chromatography. A》2004,1033(1):145-151
The new type of silica gel surface modification with using the trimethylamine as a reagent is described. The samples of chemically modified silica gel have been used for generation of gaseous standard mixtures (methyl chloride as a measurand) using the technique of thermal decomposition of the surface compound. The main aim of the research was to check the suitability of the new type of silica gel surface modification for obtaining methyl chloride as a measurand of gaseous standard mixture. The gaseous standard mixture obtained with using this technique was used for calibration of a thermal desorber-gas chromatography-flame ionization detector (TD-GC-FID) system. The homogeneity of coverage of silica gel surface with the immobilized compound has been evaluated. The full uncertainty budget of determination of liberated amount of methyl chloride has been calculated. The average amount of methyl chloride liberated from the unit sample of chemically modified silica gel is 3.59 +/- 0.13 mg g(-1). The influence of the modification way on the amount of liberated analyte has also been determined. 相似文献