纳米材料与纳米技术的研究方向及应用前景

纳米材料具有独特的表面效应、体积效应和量尺寸效应，使得材料的性能发生突变，纳米材料及采用纳米材料的纳米技术也因此成为材料科学与工程研究及应用最重要的发展方向之一。对国内外纳米材料及纳米技术的研究现状及其广阔的应用前景进行了综述，同时对纳米材料研制开发中的重要基础理论问题进行了探讨。     

稀土对藻类生物效应的研究进展

从藻类的生长状况和生理特性两个方面,总结近年来关于稀土对藻类生物效应的研究结果,目前研究表明,稀土对藻类的生物效应与稀土元素的种类和藻类的品种密切相关,因此进一步对更多的藻种开展研究是有意义的。现有的结论多是在实验室条件下得到,建议应充分涉及环境因素对该生物效应的影响及其规律,同时,进一步完善从细胞分子水平对该生物效应的认识。     

多氯联苯对2种微藻的急性毒性研究

[目的]研究多氯联苯对海洋浮游植物的急性毒性.[方法]选择珠江口海域赤潮优势种锥状斯氏藻和热带骨条藻进行多氯联苯急性毒性试验,研究其半效应浓度(EC<,50>),分析多氯联苯对其生长以及超氧化歧化酶(SOD)和过氧化氢酶(CAT)的影响.[结果]多氯联苯对锥状斯氏藻、热带骨条藻生长有明显的抑制作用,对2种藻类的96 h半效应浓度(EC<,50>)分别为0.103和0.009 mg/L.低浓度多氯联苯对2种微藻的SOD和CAT活性有诱导作用.当多氯联苯浓度超过一定阈值,酶活性下降;与锥状斯氏藻相比,热带骨条藻对多氯联苯暴露更敏感,耐受力较差.[结论]该研究为深入研究持久性污染物对海洋浮游植物的毒性效应提供了依据.     

纳米材料生态毒理学研究进展

纳米技术给人类带来利益的同时也给人类及整个生态系统带来了潜在的危害纳米材料毒理学的研究对于科学地评价纳米材料的潜在危害和对纳米材料的生产和应用进行科学的管理是十分必要的.概述了纳米材料生物毒理学的研究进展,提出了研究中存在的不足,并对其研究前景进行了展望.     

低维纳米材料的制备方法与金属纳米材料

纳米材料的纳米晶粒和高浓度晶界特征以及由此而产生的小尺寸量子效应和晶界效应，使其具有特殊的力、电、磁、声、光等性能。晶粒尺度在1～100nm范围内的金属纳米材料具有强度、硬度高，韧性好、损耗低，比热高，磁化率高、矫顽力高等特性，是具有广阔应用前景的新型材料。综述了目前国内外低维纳米材料的制备方法、表征技术和研究成果，并对这些方法和成果进行了比较研究，着重介绍用这些方法所制备的金属纳米材料及其在科学领域中的应用。     

纳米材料应用现状及发展趋势

纳米材料是近期发展起来的多功能材料 ,本文概述了纳米材料的结构特性、主要制备工艺及应用现状和发展趋势 ,由于纳米材料具有许多特殊功能和效应 ,将在工业和国防等领域中发挥巨大潜力 ,并将为人类社会带来巨大影响。     

苯胺类二元混合物对汴河水中混合细菌的联合毒性研究

[目的]为苯胺类化合物的生态风险评价提供理论依据.[方法]以汴河水为细菌来源,24 h-IC50为生化毒性指标,研究苯胺及其6种衍生物对细菌的联合毒性效应.[结果]甲基苯胺混合物对细菌的联合毒性表现为拮抗作用,氯代苯胺混合物对细菌的联合毒性表现为协同作用.同系列混合物若2组分毒性相近,则细菌对其较敏感,若2组分毒性相差较大,则细菌对其敏感性较差.[结论]苯胺类化合物的混合方式不同,其对细菌的毒性作用机理也可能不同.     

离子液体制备无机纳米"材料"研究进展

离子液体在纳米材料制备方面具有很多优势,为纳米材料的制备开辟了一条新的途径.目前,研究者已经在离子液体中制备出了零维、一维和二维纳米材料.文章就近年来国内外相关研究进展,对离子液体在无机纳米材料合成中的应用进行综述.     

藻类在黄龙钙华景观中的作用

藻类在地球及地球生命演化和物质循环过程中起到非常重要的作用,并以其独特的生理生态特性和强大的繁殖能力深刻影响着岩溶的形成与发育.在黄龙钙华景观的形成和发展过程中,藻类的着色作用,钙华沉积作用和钙华溶蚀作用是同步存在的作用体系,水体中的藻类为景观增添艳丽的颜色,藻类促进碳酸盐沉淀是重要的钙华生物成因.在外界环境发生改变的情况下,例如岩溶水缺乏时,藻类的着色作用与溶蚀作用会变得突出,大面积生长的蓝藻和生物侵蚀现象严重影响钙华景观的发育和观赏价值.笔者对钙华藻类在景观中作用的探讨为钙华景观的研究和保护提供了科学依据.     

一维钒酸盐纳米材料的合成及应用前景

一维钒酸盐纳米材料由于具有良好的光催化及电化学性能,在锂离子电池、光催化及电化学传感器方面具有很好的应用潜力.结合作者近年来的研究,论述了一维钒酸盐纳米材料的制备、性能及应用的研究现状与最新进展,分析了一维钒酸盐纳米材料可能的发展方向.     

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)