非完全消化-火焰原子吸收光谱法测定指甲中的镁锌

建立了非完全消化-火焰原子吸收光谱法快速测定指甲中镁、锌的分析方法,在低温下用浓硝酸消解样品,可获得均匀、透明的样品溶液.以空白溶液为参比,用工作曲线法测定.对样品处理条件、化学干扰、硝酸的影响、试液与空白溶液粘度一致性、背景吸收干扰及检出限进行了考察.测定结果的相对标准偏差小于2.9%,测定结果为灰化法一致,相对误差小于±20%.方法简便、快速、准确.     

悬浮液进样-火焰原子吸收光谱法测定芦荟中钙、铁

用悬浮液技术处理芦荟样品,建立了悬浮液进样-火焰原子吸收光谱法快速测定芦荟中钙、铁的分析方法.分别以La3+和盐酸作为钙、铁的释放剂.对琼脂溶液用量、化学干扰、试液与空白溶液特性的一致性、背景吸收干扰及检出限进行了考察.测定结果的相对标准偏差小于3.2%,测定结果与灰化法一致,相对误差小于±0.9%,方法简便.     

火焰原子吸收光谱法快速测定黄瓜中的钙和锌

采用悬浮液法和非完全消化法分别对黄瓜样品进行处理,建立了悬浮液法和非完全消化法-火焰原子吸收光谱法快速测定黄瓜中钙和锌的分析方法,以La3+作为钙的释放剂来消除化学干扰。实验表明,在悬浮液中加入适量盐酸可显著提高被测元素的吸光度,试液的物理性质与空白溶液的一致,无背景吸收干扰。测定结果的相对标准偏差小于0.9%,测定结果与灰化法一致,相对误差小于±0.7%。说明,采用火焰原子吸收光谱法,以悬浮液法或非完全消化法取代灰化法来处理黄瓜样品是可行的。     

非完全消化-火焰原子吸收光谱法测定银杏叶中钙铁锌

将非完全消化法应用于火焰原子吸收光谱法,成功地测定银杏叶中钙、铁、锌。以La3+作为钙的释放剂消除化学干扰。试验表明,试液的物理性质与其空白溶液的一致、无背景吸收干扰。对检出限及特征浓度进行考察。测定结果的相对标准偏差小于1.3%,测定结果与灰化法一致,相对误差小于±0.4%。可见,在火焰原子吸收光谱法中,以非完全消化法取代灰化法处理银杏叶样品是可行的。     

啤酒中金属的测定

本实验建立了利用非完全消化-火焰原子吸收光谱法快速测定了啤酒中的锌、钙、镁金属元素含量。用标准曲线测定。对非完全消化法样品处理条件、干扰、试液的物理性质与其空白溶液的一致性、检出限及特征浓度进行了考察。测定结果的相对标准偏差小于2.0%,本方法的测定结果与灰化法一致,相对误差小于±2.9%。     

悬浮液技术-火焰原子吸收光谱法测定银杏叶中钙铁锌

将银杏叶样品粉碎、过筛并悬浮在1.5g/L琼脂溶液中制成悬浮液,以火焰原子吸收光谱法成功地测定了银杏叶中钙、铁、锌。用L a 3+作为钙的释放剂以消除化学干扰。试验表明,加入适量盐酸可显著提高被测元素的吸光度。对盐酸溶液(1+1)用量、试液与空白溶液粘度的一致性、背景吸收干扰、检出限及特征浓度进行了考察。测定结果的相对标准偏差小于1.8%,测定结果与灰化法一致,相对误差小于±0.9%。可见,在火焰原子吸收光谱法中,以悬浮液法取代灰化法处理银杏叶样品是可行的。方法简便准确。     

啤酒中金属的测定

本实验利用非完全消化-火焰原子吸收光谱法快速测定啤酒中的锌、钙、镁金属元素含量的分析方法,用标准曲线测定。对非完全消化法样品处理条件、干扰、试液的物理性质与其空白溶液的一致性、检出限及特征浓度进行考察。测定结果相对标准偏差小于2.0%,本方法的测定结果与灰化法一致,相对误差小于±2.9%。     

乳化技术-FAAS法测定硬脂酸盐中主金属元素

将样品在盐酸溶液中加热，硬脂酸盐分解形成硬脂酸，用乳化剂OP乳化硬脂酸而配制成透明或半透明的乳浊液，建立了快速测定硬脂酸盐中主金属元素的乳化技术一火焰原子吸收光谱法（FAAS）。用工作曲线法测定。对样品处理条件、化学干扰、介质的影响、硬脂酸根基体影响及背莆吸收干扰进行了考察。测定结果的相对标准偏差小于4．3％，加标回收率在96．7％～103．7％范围内。     

火焰原子吸收光谱法测定茄子中钙镁

本文建立悬浮液技术及非完全消化 -火焰原子吸收光谱法快速测定茄子中钙、镁的分析方法。试验表明 ,在悬浮液中加入适量盐酸可显著提高钙、镁的吸光度。对盐酸溶液用量、化学干扰、背景吸收干扰、试液与空白溶液物理性质的一致性进行考察。测定结果的RSD小于 1.1% ,测定结果与灰化法一致 ,相对误差小于± 1.0 %。     

在氨性溶液中以火焰吸收原子吸收光谱法测定胶乳中的镁锌

先用浓硝酸消解样品，再用氨水溶解消解产物，建立了在氨性溶液中快速测定胶乳中镁、锌镁的FAAS法。另入少量氯化铵以控制溶液pH值防止生成氢氧化镁，并以Sr^ 2作为镁的释放剂。对样品处理方法、消解产物的溶解性质、加入氯化铵的作用、线性范围及干扰进行了考察。测定结果与灰化法一致，相对标准偏差小于2.40%,加标回收率为99.6%-100.2%。方法简便、快速、准确。     

Quantitative measurements in in situ straining experiments in transmission electron microscopy

Several examples of recent studies by in situ straining experiments in a transmission electron microscope performed in the Toulouse group (France) are presented. In particular, quantitative measurements of the features of the dislocation motion are described. These examples deal with individual or collective propagation of dislocations, which are submitted to various types of obstacle. Different metallic materials are investigated: magnesium, intermetallics, aluminium alloys and γ phase of a superalloy.     

Some recent progress in microtribology in Japan

The micro in the word of microtribology is defined as science and engineering supported by modern physics and chemistry. In the engineering area, the ultimate goal of microtribology is to create practical zero-wear devices. The importance of microtribology was recognized by Japanese scientists and engineers in the latter half of the 1980s, and much progress has been made in microtribological studies of mechanisms of friction, lubrication with very thin liquid films, and microwear processes.     

中国创造与工业设计

本文通过对“中国制造”现象的分析,阐述了设计作为一项基本国策的紧迫性,并认为工业设计是提升企业国际竞争力的主要途径之一。21世纪的国际竞争实质是设计和创新的竞争。只有实现由“中国制造”向“中国创造”的跨越,才能使我国在国际经济竞争中赢得主动权和市场份额。     

奶牛过瘤胃液中氨基酸的研究进展

本文综述了奶牛过瘤胃液氨基酸的概念、分类、检测方法、应用效果、影响因素及存在的问题和应用前景     

Lubrication in steel strip rolling in Japan

Research into, and the state of technology for, lubrication in steel strip rolling in Japan are reviewed. Both cold and hot strip rolling are discussed. Subjects covered include coefficient of friction and oil film thickness, friction pick-up, and roll wear.     

在多元中融通 在理解中共生——多元文化背景下的国际理解教育

多元文化的态势随着全球化的加剧日趋明显,各类文化的共生共荣需要通过国际理解教育的推动而实现。国际理解教育的要义在于培养国际理解精神、创建和平文化、推动和平、人权和民主以及促进理解、尊重及共同发展。在多元文化背景下,学校实施国际理解教育不仅有助于培养学生的世界公民意识、文化多元意识,而且有助于激发学生的民族认同感和民族自豪感、形成学生的平等观和关爱心并促进学生道德水准的实质提升。国际理解的达成需要在知识掌握、视野扩展、充分了解中,在扩大开放、增进交流、平等对话中,在环境浸淫、生活体验及实际行动中实现。     

Developments in tribological materials in the next millennium

The materials needed for tribological contact systems in the next millennium will depend on the trend and pace of technological development, and environmental policy. The latter will certainly demand lower pollution and energy consumption, so materials should preferably be light, and work in most friction systems without lubrication, but with low friction, and no wear. The following properties, or requirements, of future tribomaterials can be conceived of in such a scenario: it seems likely that micro‐mechanical systems will achieve great importance, but silicon must be either surface protected or replaced by an optimised material; light metal alloys must be conditioned by surface treatment or coating; coatings must be improved, e.g., by nanomaterials; ceramic materials sintered at low temperatures from nano‐powders will be ductile and machinable, but retain the other beneficial properties of ceramics; and ultra‐precise surface finishing of materials may lead to nearly friction‐free and wearproof tribocontacts.     

Microglia-precursor cell interactions in health and in pathology

Until recently, microglia were mainly known as the resident phagocytes of the brain, i.e. the ‘immunological warriors’ of the brain. However, extensive knowledge is being accumulated about the functions of microglia beyond immunity. Nowadays, it is well accepted that microglial cells are highly dynamic and responsive, and that they intervene in a dual manner in many developmental processes that shape the central nervous system, including neurogenesis, gliogenesis, spatial patterning, synaptic formation and elimination, and neural circuit establishment and maturation. The differentiation and the pool of precursor cells were also shown to be under microglia regulation via bidirectional communication. In this concise review, I discuss our recent work in microglia-Pax6⁺ cell interactions in one of the circumventricular organs, the pineal gland. An analogy with the rest of the central nervous system is also presented. In addition, I briefly examine mechanisms of interaction between microglia and non-microglial cells in both health and disease. New avenues are also introduced, which may lead us to better comprehend the impact of microglia in physiological and pathological conditions.     

Podocyte electrophysiology,in vivo and in vitro

Podocytes are the most differentiated cell types in the glomerulus, which have been assumed to participate in the regulation of the ultrafiltration coefficient K(f). In podocytes in vivo and in vitro vasoactive agonists, such as angiotensin II and acetylcholine, increase the free cytosolic Ca(2+) concentration via a release of Ca(2+) from intracellular stores and an influx of Ca(2+) from the extracellular space. An increase of the cytosolic Ca(2+) in podocytes activates Cl(-) channels in podocytes in vivo and in vitro, resulting in a depolarization of podocytes. In vitro studies have shown that in addition to Ca(2+)-activated Cl(-) channels, cAMP-activated Cl(-) channels and Ca(2+)-activated K(+) channels are present in cultured podocytes. The characterization of the signaling pathways that regulate ion channels in podocytes may be important in the understanding of the regulation of the ultrafiltration coefficient K(f). This review summarizes the currently known electrophysiological properties of podocytes.     

工程计算的程序实现的几点体会

根据作者的工作经验，讲述了工程计算程序编制的步骤，特别强调了人的经验在编制程序中的重要作用。