分离富集技术在痕量贵金属分析中的应用与进展

贵金属具有良好的抗腐蚀性、稳定的热电性、高温抗氧化性及良好的催化特性,在国民经济各个领域应用广泛。由于对贵金属的需求量逐年剧增,以及其在一次资源和二次资源中含量极低,使得贵金属分析中的分离富集技术不断向痕量、超痕量方向发展。文章综述了近年来国内外痕量贵金属分析中分离富集技术的研究进展,对火试金法、共沉淀法、吸附分离法、溶剂萃取法等分离富集方法进行了归纳总结,对存在的问题进行了分析探讨,并对未来分离富集技术发展趋势进行了展望。文章提出,应对现有分离富集技术原理进行多角度深入研究,并不断开发与仪器分析相适应的贵金属分离富集新技术,同时加大对铑、铱、钌、锇4种贵金属元素分离富集方法研究的力度。     

离子液体在萃取分离中的应用进展

简要介绍了离子液体及其特性,综述了近几年来利用离子液体萃取分离不同物质的研究进展情况。离子液体在萃取金属,包括碱金属、过渡金属、稀土金属等离子中的应用比较广泛;在萃取有机物,包括多环芳烃、酚类物质、共沸混合物等中的应用也很多;在萃取生物分子包括生物碱、双链DNA(脱氧核糖核酸,Deoxyribonucleic acid)、雌激素物质等也有一定的应用;在萃取脱硫中的应用相对少一些,主要是噻吩类物质;此外,离子液体还应用于有机磷农药、中草药、四环素类抗生素的萃取分离。本文主要从这些应用中的萃取体系、分离物质、测定结果等方面进行了归纳和概述。离子液体作为一种环境友好的高效溶剂,研究成果不断涌现,应用前景较好。     

浮选技术在金属分离/富集及分析中应用研究进展

浮选技术适于从稀水溶液中富集痕量金属离子,且可用光谱分析法直接分析。本文综述了1996~2007年浮选技术在金属分离/富集及分析中应用研究进展,对浮选的分类(离子浮选、沉淀浮选、溶剂浮选)和机理做以简单的概述,介绍了捕集剂浓度、溶液pH值、离子强度、气体流速等因素对浮选效率的影响,从捕集剂选择、pH值、浮选剂或表面活性剂的选择及回收率等方面对浮选技术在金属分离/富集及分析中的应用进行总结,并指出浮选技术存在的问题和发展方向。     

析相萃取(浮选)在贵金属分离富集中的应用

析相萃取(浮选)技术是近年来出现的一种新的分离富集方法。中介绍了该技术的基本原理及主要影响因素,并综述了该技术在贵金属分离富集中的研究与应用现状。     

自动萃取化学光谱法测定高纯金中12种金属杂质

沈阳冶炼厂对高纯金中12种杂质元素的自动萃取化学光谱法的测定作了研究。高纯金中的杂质元素一般采用光度法或化学光谱法测定,后者不但分析检测限低,且可同时进行多元素的测定。他们应用回流自动萃取器在1.2N盐酸的溶液中,用乙醚回流萃取基体金。这种分离基体金的方法取代了手工操作,     

分离富集在原子吸收光谱分析法中的应用

叙述了分离富集在原子吸收光谱分析法中的应用，其中简述了壳聚糖、液膜巯基棉、黄原酯棉、萃取分离、共沉淀以及其它分离富集等方法。     

离子缔合萃取在湿法冶金中的应用近况

<正> 离子缔合萃取在湿法冶金中有着广泛的应用,包括从浸出液中回收金属;分离性质相似的金属元素;浸出液的净化等领域。钴、镍、铜、锌、锡、钨、稀土,以及稀散     

原子荧光光谱法测定地质矿物样品中痕量金属元素研究

痕量金属元素广泛分布于矿物中,长期接触会对人体产生危害,研究原子荧光光谱法测定地质矿物样品中痕量金属元素.准备主要仪器设备与试剂,配置标准溶液,设定原子荧光光谱仪工作条件,通过无机离子萃取方法,处理样品,完成测定.经实验结果分析,本文方法测定痕量元素镉的结果准确度较高,适用于地质矿物样品的测定.     

原子荧光光谱法测定土壤中的铅、铬、镉、汞、砷、锌、铜、镍等元素研究

土壤无机污染物铅、铬、镉、汞、砷、锌、铜、镍这八大重金属,是一般土壤检测中的必检项目。金属元素在土壤中积累富集后,有可能通过雨水迁移,造成地下水,地表水污染,或者通过农作物进入食物链,进而影响食品安全和人体健康,因此,对这些元素的检测显得尤为重要。本文采用原子荧光光谱法对土壤中的金属元素进行测量,同时结合微波消解技术对样品进行处理,确保测量数据的准确性。     

稀土萃取分离过程三相乳化物的研究Ⅰ——无机杂质富集沉淀导致的乳化

对中钇富铕稀土矿萃取分离过程中产生的三相乳化物进行了物相分离和组成分析,确认第一分离段发生累积性三相物乳化的主要原因是原料中的难溶性固体物质累积,后续各分离段发生累积性三相物乳化的主要原因则是由于氟离子富集后生成了较多稀土氟化物沉淀。     

The effect of amount of possession of the trait of hostility on accuracy of perception of hostility in others.

Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparison of rates of infection of two methods of emergency ventricular drainage

The rates of infection of two methods of external ventricular drainage in use at Atkinson Morley's Hospital--namely, (a) percutaneous drainage with Rickham reservoirs and (b) tunnelled ventriculostomies--were compared in this retrospective review. Percutaneous drainage of CSF with Rickham reservoirs was associated with a 27% rate of infection as identified by positive microbiological cultures; tunnelled ventriculostomy catheters had a 10% infection rate. The difference in the infection rate between the two methods was statistically significant (P < 0.015). Other variables examined, including the age and sex of the patients and the reasons for ventricular drainage, were not associated with an increased rate of infection. Most infections from either method were caused by a coagulase negative staphylococcus. The average duration of ventricular drainage before identification of positive cultures was 5.7 days for Rickham reservoirs and 6.0 days for ventriculostomies.     

Effect of antibiotics of chemotaxis of human leukocytes

The effect of 20 different antibiotics on chemotaxis by human neutrophils was studied. Human leukocytes incubated with chloramphenicol, rifampin, sodium fusidate, and tetracyclines in vitro showed markedly depressed migration. The mechanisms by which these antibiotics affect leukotaxis are discussed.     

Quality of life of relatives of mental patients

Usage of quality of life of psychiatric patients' relatives as the parameter of estimation of the quality of psychiatric care is considered. By means of standard questionnaire elaborated by the authors as well as by means of both individual and group conversations the quality of life was analyzed in 40 relatives which lived together with psychiatric patients. Different spheres of their life and difficulties (financial, social-psychologic, production) were examined in families with such patients. The defects of psychiatric care that had direct influence on the quality of life of the psychiatric patients' relatives are outlined.     

浅析《野草》的版画特征

鲁迅先生一生热爱美术作品,对版画中木刻兴趣尤甚.<野草>作为其"写心之作",亦呈现出一些与木刻版画一致的审美特征:一是具有木刻版画的色彩特征,多对比、多冷色,有阴郁的美感;二是具有木刻版画的力度特征,环境描写、人物刻画处处刀锋毕现,遒劲有力,有一种"力之美".     

四辊破碎机车刀架的改造

针对四辊破碎机车刀架车削中存在的几个问题,详细介绍了电动车刀架的结构和工作原理,建立主要设计参数的数学表达式,并进行适当的分析。改造后,这种电动车刀架运行平稳、可靠、方便、省力,取得了预期的效果。     

转炉炉壳热应力分析

根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。