尿中铷的原子吸收测定

从事铷盐生产的人员,或多或少地会从口或鼻中引进铷盐,其同位素Rb-86具有放射性,对人体有害。铷同钾、钠一样,能由肾脏进入尿液。通过尿中铷的测定,可以考察劳动保护措施的效果。微量铷的测定,通常使用原子吸收法测定。由于尿中含钠量高,且含有机物,干扰铷的测定。文献报导了用仲-BAMBP萃取分离铷、铯。我们采用4-叔丁基-2(a-甲苄基)苯酚(t-BAMBP),将铷从尿中萃出,用盐酸反萃后进行测定。标准加料     

火焰原子吸收光谱法测定氯化物型卤水中微量铷

对火焰原子吸收光谱法测定氯化物型卤水中微量铷时共存离子,包括钾、钠、钙、镁等的干扰作了试验,并根据试验结果对文献报道的火焰原子吸收光谱法测定简单卤水中铷的条件作了改进.试验表明:当在制作标准曲线时加入与试样中含量相近的上述离子,可抵消其干扰.按此条件,毋需任何预处理,即可直接测定铷.应用此方法分析了两件已知样品中铷量,所得结果与已知值相符.以此样品为基础加入铷标准溶液作回收试验,测得回收率在92%～108%之间.     

用环爐技术分离钾、铷、铯

借助于环炉技术,用磷钨酸作交换剂,分离了微量的钾、铷、铯。先用0.1N硝酸:乙醇-1:2溶液冲洗出钾;然后借助于辅环,用0.1%硝酸银溶液冲洗出铷;铯则留于原斑点不动。操作时间不超过15分钟。钾、铷、铯离子的检出限量皆为5微克;三者的可分离最高比值为300:50:50(微克)。逾此分离不清。     

单矿物中铁的快速微量分析——Fe~(3+)-CAS-CTMAB光度测定法

铬天青-S-(CAS)-溴代十六烷基三甲铵(CTMAB)光度法测定铁(Ⅲ)已有报导,并用于测定高纯锂、铷、铯盐类中微量铁。本文将此法用于矿物、岩石中铁的测定,进行了必要的试验。方法灵敏度高,摩尔吸光系数达1.1×10~5。实验部分     

用原子吸收法测定氯锡酸铷和氯锡酸铯中的钾、铷、铯和锡

工业上以四氯化锡从提锂后富含铷和铯的混合碱母液中分步沉淀出铯和铷,以制取它们的化合物。分析上也利用上述反应作为重量法测定铷和铯的方法。有关铯和铷的氯锡酸盐中钾、铷、铯、锡的分析测定文献中未见报导。因为样品在中性或酸性溶液中极难溶解,碱融样品又会引入大量外来碱金属元素(特别是钾)而使分析造成困难。     

火焰分光光度法测定卤水中铷和铯

随着电子、自动化、宇航和原子能工业的飞跃发展,铷、铯资源的勘探和开发愈加引起重视。遗憾的是在自然界仅找到铯的矿物,因而从液体矿-卤水中提取它们,就成为一条重要途径。从基体为碱与碱土金属的卤水中分离出铷、铯存在着较大的困难,且又缺乏特效试剂,因而目前主要用仪器分析法测定,其中以火焰分光度法最为普及。我们用四苯硼钠将卤水中铷、铯随钾共沉淀分离,继溶于正丁酮-甲醇-水     

中药材马宝中铷的测定

目前 ,中药中关于铷的含量分析及其可能产生的药理作用报道不多。马宝为贵细中药材 ,是马科动物马胃肠道结石 ,主要为无机成分 ,在对其性状、显微、成分与结构进行分析的基础上[1 ] ,用火焰原子发射法 [2 ]对其中铷的含量进行了分析 ,以期进一步了解该类药物的微量元素情况。1　仪器与试剂日立 1 80 - 80型原子吸收分光光度计Eppendorf微量移液管铷标准储备液 :0 .1 mg·ml- 1 ,称取 1 0 5°C烘干1 h的氯化铷 (光谱纯 ) 0 .0 3536g,加水溶解 ,用硝酸( 1 99)溶液稀释 ,定容至 2 5ml。钾溶液 :2 0 mg· ml- 1 ,称取氯化钾 (高纯 )0 .9551 g,…     

t-BAMBP萃取-原子吸收分光光度法测定矿物中微量铷、铯

利用4-叔丁基-2-（α-甲苄基）酚（t-BAMBP）萃取矿物中微量的铷和铯,再利用原子吸收分光光度法测定其在萃取剂中的浓度．并对稀释剂的选择、萃取酸碱度、相比影响、萃取时间及干扰离子等进行了研究．实验结果表明,检出限分别为铷:0.02μg/g,铯:0.08μg/g。标准浓度在0~200μg/50mL时,线性关系大于0.9989,样品加标回收率为96.4%~104.4%之间,相对误差小于1%．     

标准加入-原子吸收光谱法测定卤水中的铷和铯

卤水学名为盐卤,是由海水或盐湖水制盐后残留于盐池内的母液,主要成分有氯化镁、硫酸钙、氯化钙及氯化钠等,味苦、有毒。卤水中铷和铯的提取方法是国内外学者的研究热点,因为卤水中铷和铯的浓度直接决定提取方法的选择和提取价值的大小,因此对卤水中铷和铯测定方法的研究具有重要的意义。     

冠醚取代酞菁超分子体系的光谱性能研究

本文合成了苯并[15-冠-5]取代的酞菁化合物,研究了铷离子诱导的冠醚酞菁二聚行为的光谱特性,观察到冠醚酞菁形成二聚体的光谱变化分三阶段进行,与铷离子的浓度密切相关,这是由于二聚体中酞菁环从非共平面构象最终转变为面对面的超分子结构的结果;详细介绍了对紫外可见吸收光谱中重叠光谱的数据处理方法,从而计算了二聚体形成的平衡常数K值。     

铝酸钠溶液脱硅的研究进展

对硅在铝酸钠溶液中的存在状态,深度脱硅机理和研究进展,碱法生产氧化铝过程中铝酸钠溶液脱硅的重要性以及铝酸钠溶液脱硅的研究方向进行了综述。     

铝酸钠溶液的鲁米诺增强声致发光研究

Ultrasonic processing on sodium aluminate solutions was proved to have effects on the gibbsite crystallization process from sodium aluminate solution. In order to investigate the mechanism of the ultrasonic intensification, the sonofluorescence spectrum was detected by fluorescence spectrometer in sodium alumiante Luminol solutions, and the spectrum under the conditions of various ultrasonic power and different composition of sodium aluminate solutions were studied. It is found that the sodium aluminate Luminol solution can irradiate fluorescence by ultrasonic processing above the given power; the intensity of sonofluorescence are relatively low in sodium aluminate solutions with high concentration and low αk（mol ratio of Na2O/Al2O3 in sodium aluminate solution）. The relationship between the sonofluorenscence and ultrasonic intensification on gibbsite crystallization process from sodium aluminate solutions were also discussed. The conclusion that the ultrasonic effects are influenced by ultrasonic cavitation and intensity of sonofluorescence spectrum is deduced.     

过饱和铝酸钠溶液结构性质与分解机理研究现状*

过饱和铝酸钠溶液分解是氧化铝生产过机理的研究是氧化铝生产过程的重要基础问题.本文对过饱和铝酸钠溶液中铝酸根离子存在的基本形态,浓度、苛性比和阳离子对铝酸钠溶液结构性质的影响,溶液中多种铝酸根离子平衡与转化规律,以及铝酸钠溶液分解机理研究的现状进行了总结和评述;分析了现有铝酸钠溶液结构性质与分解机理研究的不足;围绕强化氧化铝生产中铝酸钠溶液分解过程的目的,提出了铝酸钠溶液结构性质与分解机理研究的重点.     

聚酰胺―胺的合成表征及对铝酸钠溶液物化性质的影响

用发散法合成以乙二胺为核的聚酰胺―胺(PAMAM 0.5～6.0代),采用元素分析、电位滴定等方法对合成产物进行表征分析,考察了不同分子代数、不同浓度的PAMAM对铝酸钠溶液表面张力和电导率等物理化学性质的影响。结果表明,该条件下合成的PAMAM具有较好的结构完整性。此外随着添加剂PAMAM的增加,铝酸钠溶液的表面张力急剧降低,半代数的PAMAM具有较好的表面活性,有望成为新一代的表面活性剂;整代数的PAMAM也有一定的表面活性。PAMAM属于非离子型表面活性剂,因此随着PAMAM的加入,铝酸钠溶液的电导率改变不大。     

溶胶-凝胶法制备纳米氢氧化铝溶胶

研究了利用铝酸钠溶液碳酸化产生的沉淀, 经胶溶作用制备出纳米氢氧化铝溶胶的过程. 分析了铝酸钠溶液滴加到大量碳酸氢钠溶液中时发生的反应. X射线衍射研究结果表明, 在纳米氢氧化铝溶胶制备过程中, 从无定形氢氧化铝沉淀到拟薄水铝石的晶型转变过程是氢氧化铝沉淀胶溶时溶解再析出的过程. 将碳酸氢钠加入到苛性比为1.7的铝酸钠溶液中, 中和至苛性比为1.3后, 溶液诱导期中的紫外光谱显示270 nm处的Al(OH)3-6吸收增强. 经与含铝原子六配位的晶体紫外光谱对比后表明, 在铝酸钠分解生成氢氧化铝的过程中, 其铝的配位结构从四配位转化为六配位. 拟薄水铝石溶胶粒子的形貌与胶溶所用的酸和分散剂有关.     

Method for synthesis of sodium aluminate by caking products from the mud storage area of aluminum plant

Results obtained in a study of the topographic, layer-by-layer, chemical, and mineralogical composition of products in the mud storage area of an aluminum plant and in an analysis of the kinetics and mechanism of processes occurring in synthesis of sodium aluminate by the caking method are presented. It is shown that the processing mode affects the yield of sodium aluminate in the cake and the coagulating properties of the resulting sodium aluminate.     

Herstellung und Eigenschaften von Aluminiumaquoxid. II. Böhmit aus Natriumaluminat und Salpetersäure

Preparation and Properties of Aluminium Hydroxide. II. Boehmite from Sodium Aluminate and Nitric Acid A report is given on the physical-chemical characteristics of aluminium hydroxide which contain mainly boehmite, having been obtained by continuous precipitation from sodium aluminate solution with nitric acid using technical raw materials and conditions being very similar to those applied in production. The influence of the reaction conditions (pH value, temperature, concentration and residence time in the precipitation suspension) on the chemical composition, structure and texture of the hydrogels is studied. With rising precipitation temperature the pH range extends, within which already after short residence times pure-phase, relatively well crystalline boehmite hydrogels are obtained in the precipitated solution.     

Nitrat-, Thiosulfat-, Sulfat- und Sulfid-Cancrinit

Nitrate-, Thiosulphate-, Sulphate-, and Sulphide Cancrinite

• 1 For the synthesis of the compounds to a solution of sodium aluminate there is added in excess sodium nitrate, or sodium thiosulphate, or sodium sulphite, or sodium sulphide. After heating a solution of sodium silicate is added, and the suspension is hold at 110°C for a long time, the precipatite is filtered, washed, and dried.
• 2 The white compounds are characterized in composition and crystal structure by chemical and X-ray analysis and densities.
• 3 The unimolecular hexagonal cell of the compounds has the cancrinite structure (lattice constants and densities see ?Inhaltsübersicht”?).
• 4 By heating of thiosulphate cancrinite at 1 000°C in air there is produced a nice deep blue coloured pigment.

     

Determination of gallium in bayer process sodium aluminate solution by inductively coupled plasma atomic emission spectrometry

The determination of gallium in sodium aluminium solutions by inductively coupled plasma atomic emission spectrometry is reported. The spectral line profiles of three Ga lines are recorded over a short wavelength region in the presence of interfering ions, by varying the observation height from 8 to 20 mm and the RF power from 1.0 to 1.75 kW. Under fixed ICP conditions, matrix interferences are observed. The results indicate a complex matrix effect on gallium in the presence of different concentrations of sodium. The proposed method is applied successfully to the determination of gallium (110–120 μg ml^?) in Bayer process aluminate solution.     

Preparation and Thermal Decomposition of Synthetic Bayerite

The formation process of bayerite, from an aqueous solution of sodium aluminate through enforced decomposition of aluminate ions by introducing CO₂ gas and aging with mechanical stirring, was investigated by pH measurements of the mother solution during preparation reaction and characterization of precipitates obtained at various stages of preparation. An amorphous precipitate, produced initially by the reaction of introduced CO₂, transformed to bayerite via pseudoboehmite during aging. It was found that the crystalline particle size and morphology of the crystallized bayerite change depending systematically on the preparation conditions. The reaction pathway of the thermal decomposition of the synthesized bayerite was investigated by using thermoanalytical techniques. This revised version was published online in July 2006 with corrections to the Cover Date.