硫酸介质中氯化镧与阴离子表面活性剂十二烷基苯磺酸钠(SBDS)对锌的缓蚀协同效应

用失重法研究了硫酸介质中稀土镧(Ⅲ)离子和阴离子表面活性剂十二烷基苯磺酸钠(SBDS)在硫酸介质中对锌的缓蚀协同效应.发现La3+在低浓度下有增蚀作用;SBDS对锌则有一定的缓蚀作用,但最大缓蚀率仅有35%.实验结果亦表明SBDS与La3+对锌表现出强烈的缓蚀协同效应.     

表面活性剂对磷钾伴生矿提钾过程的影响

在HCl-H3PO4混酸处理磷钾伴生矿提钾过程中,考察不同类型的表面活性剂对钾浸出率的影响。结果表明,阴离子表面活性剂(十二烷基磺酸钠和十二烷基硫酸钠)的加入能将钾的浸出率提高10~15个百分点,最高可达95.01%。阳离子表面活性剂(十二烷基三甲基氯化铵)以及非离子表面活性剂(聚乙二醇-6000及聚乙二醇-10000)的加入对钾的浸出产生抑制效果。     

表面活性剂强化铜矿石浸出

为了解决铜矿石浸出速度慢、浸出率低的问题,在浸出液中加入表面活性剂进行摇瓶试验.通过测量浸出前后溶液表面张力以及铜浸出率,考察了三种不同类型的表面活性剂对铜矿石浸出的影响.研究发现溶液表面张力对矿石浸出影响较大,阴离子表面活性剂的强化浸出作用最为明显,铜浸出率达62.5%.在柱浸试验中,添加阴离子表面活性剂使铜浸出率提高了近10%.利用物理化学和渗流力学对表面活性剂强化浸出机理的分析表明,溶液表面张力和表面活性剂在矿石表面的吸附对矿石表面润湿作用影响较大,表面活性剂在浸出液的持久性也是影响浸出的因素之一.      

苯基萤光酮—吐温-80胶束增溶光度法测定微量锆

锆的光度分析进展已有报导.近年来,胶束增溶光度法的应用,使测定锆的高灵敏显色体系不断出现.但一般均采用阳离子表面活性剂或两性表面活性剂,而用非离子表面活性剂作增溶、增敏剂的胶束增溶光度法并不多见.本法拟以非离子表面活性剂—吐温-80作用于锆—苯基萤光酮显色体系,且有聚乙烯醇存在下,分光光度法测定锆.在0.05～0.50N的盐酸介质中,锆与苯基萤光酮生成水溶性的     

表面活性剂—DMTAE体系用作络合滴定指示剂的研究

表面活性剂应用于络合滴定中具有许多特殊的优点,比如,在非离子表面活性剂存在下的PAN络合滴定铜等时,使终点的交换反应加速,变色敏锐。本文采用比PAN等显色更灵敏的新显色剂2—(4,5—二甲基噻唑     

钨铜复合材料中钨的分析

采用稀硝酸-氢氟酸溶样,在硝酸介质中钨以钨酸沉淀存在从而与铜分离。用氢氧化铵将钨酸沉淀溶解,以钨酸铵灼烧重量法测定钨;以电感耦合等离子体原子发射光谱法(ICP-AES)测定滤液中的残余钨,二者之和为总钨量。此方法已用于测定钨铜材料中质量分数大于10%的钨,结果与认定值相符。     

连续测定银电解液中游离硝酸及铜银

介绍了以溴甲酚绿为指示剂，用氢氧化钠滴定游离硝酸，在醋酸缓冲液存在下以DETA络合滴定铜(Ⅱ)，再用铁铵矾为指示剂，在稀硝酸介质中以硫氰酸盐滴定银。     

国外简讯

废银催化剂载体的处理包括向废催化剂和稀硝酸的循环流体(在铜离子存在下)中鼓入空气,并在循环流体中同时进行电沉淀,以保持溶液中银离子浓度为10～40g/L。最佳的硝酸浓度为5～7％,铜离子浓度为102g/L。 这是从催化剂废料中回收银和催化剂载体的最简单而经济的方法,该催化剂主要用于从乙烯和氧生产环氧乙烷。其优点是使用的硝酸量很少,不需要亚硝气,并且银的电沉淀更容易进行。     

微波消解-亮绿SF-过氧化氢体系催化动力学光度法测定铜尾矿中痕量铜(Ⅱ)

研究了在稀HNO3介质中,以十六烷基三甲基溴化铵(CTMAB)表面活性剂为增敏剂,痕量铜(Ⅱ)可催化过氧化氢氧化亮绿SF褪色,据此建立了催化动力学光度法测定痕量铜的新方法。对分析方法进行优化,确定褪色检测波长为635nm。同时,建立了反应动力学方程,确定此反应对亮绿SF试剂为零级反应,对痕量铜为一级反应。在最优化条件下,方法的检出限为0.23×10-9g/mL,Cu2+的质量浓度在0～20ng/mL范围内与吸光度变化值(ΔA)呈良好的线性关系。经使用掩蔽剂可以有效地消除其它共存离子的干扰。方法结合优化的微波消解技术对铜尾矿样品进行处理,并用于两种铜尾矿中痕量铜(Ⅱ)的测定,相对标准偏差分别为3.8%和2.4%,加标回收率为97%～99%。     

磷锑钼杂多酸-孔雀绿-聚乙烯醇体系分光光度法测定压延磷铜板中微量磷

在硫酸介质中,钼酸铵和酒石酸锑钾与磷形成的杂多酸阴离子再与孔雀绿形成离子缔合物,在聚乙烯醇的作用下,测定磷的灵敏度明显提高,据此提出了在水相中测定压延磷铜板中微量磷的分光光度法。探讨了显色剂、表面活性剂、缓冲溶液的用量以及显色时间等对吸光度的影响,着重考察了不同的表面活性剂对体系的增溶增敏作用。实验测得离子缔合物的最大吸收波长为650 nm,表观摩尔吸光系数为1.52×105L mol-1.cm-1,磷含量在0~0.40μg/mL内符合比尔定律。样品中大量铜的干扰采用硼氢化钾还原沉积,使基体中大量铜与微量     

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。     

焦炭热性能指标意义浅析

通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。     

Results of treatment of cancer of the cardia

Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.     

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.     

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)