我国对海洋锰结核的研究取得初步科研成果

据悉冶金工业部长沙矿冶研究院对中太平洋北部锰结核物质组成和加工工艺的研究已获得了初步科研成果。锰结核物质组成的研究运用多种近代物、化手段对中太平洋北部锰结核的外部特征、结构构造、化学成分、矿物组成、元素     

在有深海锰结核作氧化剂条件下,通过酸性氧化浸出黄铜矿提取铜、锌、镍和钴

Tomas Havlik等研究了在盐酸介质中有深海锰结核存在条件下浸出黄铜矿时，温度、酸浓度和物料成分的影响。黄铜矿借助于含有氧化锰的深海锰结核与盐酸反应释放出的氯气得以溶解。因为深海锰结核中存在锌、镍、钴及铜，所以研究了这些金属在浸出过程中的行为。当锰结核与黄铜矿的混合物用作初始物料时，这些金属的回收率更高。黄铜矿和锰结核都溶解之后，这些金属很快进入溶液。随后过程开始变慢甚至停止，金属从溶液中消失。这种现象的出现是因为可逆氧化电位改变、一些固体金属化合物发生了沉淀。     

豫西杜关锰结核稀土元素地球化学

豫西杜关锰结核产于华北地台南缘,中元古界官道口群龙家园组下段。杜关锰结核ＲＥＥ范围为（４０．０９～７４．７５）×１０－６,平均为５２．１４×１０－６,为极贫ＲＥＥ型锰结核。锰结核稀土元素经北美页岩标准化后的分布模式较平直,略左倾;Ｃｅ呈弱正异常、无异常和弱负异常,Ｅｕ均呈较显著的正异常。Ｃｅ异常的离散性反映了结核生长过程中氧化—还原条件的波动。杜关锰结核稀土元素具双重来源———海底深部上升热液源和海水源,前者占绝对的优势。杜关锰结核形成于海底深部热液作用的海水体系,属热水沉积成因。     

液相氧化法从海底锰结核中浸出锰

开发了液相氧化法处理海底锰结核的工艺，并对结核中锰的浸出进行了研究。初步实验结果表明：该工艺在技术上是可行的，在一定温度、空气流量及碱矿比条件下，锰结核中的锰大部分能被从结核中浸出。通过对结核中锰浸出率的各影响因素的考察，提出了液相氧化法从海底锰结核中提取锰的适宜工艺条件。该工艺不仅适用于浸出海底锰结核，还可应用于陆地相似金属矿的处理。     

海洋锰结核开采的扬矿设施试验研究进展

海洋底部的锰结核用矿浆泵或空气提升泵或经数千米长的管道提升到洋面的采矿船上。本文概述了锰结核扬矿特性的基础研究情况。     

重介质旋流器在黄茅山选厂选别锰结核的生产实践

黄茅山矿区砂矿中,含有大量的锰结核,其中含铅3～10%,含锰18～25%,是综合利用的原料.长期以来,由于没有回收这种锰结核,在磨矿作业中经磨细后大量流失于尾矿中. 1965年在昆明冶金研究所进行了采用φ300毫米重介质旋流器回收锰结核试验     

中国海底锰结核处理技术研究概况

21世纪是海洋的世纪。海底锰结核中含有大量的锰、铁、铜、钴、镍等金属元素，被公认为是一种重要的陆地矿产替代资源。自其被发现以来就引起了各国相关人士的极大关注，而如何合理开发利用海底锰结核、早日实现商业化生产则一直是关注的焦点所在。半个世纪以来，国内外众多学者进行了大量研究工作，提出了许多处理海底锰结核的工艺和方法，新的探索也一直在继续。本文重点对中国开展的海底锰结核处理技术及其非冶金加工利用的研究情况进行了介绍。     

铁锰结核的工艺性质

为评价新型矿物原料的综合利用情况,对海洋铁锰结核的工艺性质进行了系统的研究。研究工作包括对铁锰结核化学稳定性和吸附性质的考查以及其中所含各元素赋存状态的探讨。为确定金属阳离子在铁锰结核上吸附的基本规律,采用了在离子交换实践中使用的方法:制取动力学曲线(有限容积方法)、在静态和动态条件下,从单组分、双组分或     

氨介质中单质硫还原浸出锰结核

氨介质中单质硫还原浸出锰结核海洋锰结核是铜、钻、镍等的潜在资源。本文对在氨介质中还原浸出锰结核回收铜钴镍进行了广泛的研究．在早期的研究工作中，在氨介质中采用各种不同的还原剂：亚铜离子和一氧化碳、低价锰离子、硫化亚铁、硫酸亚铁、葡萄糖、甲醛和碳水化合物...     

用电解氯化法从海洋锰结核中回收铜、镍和钴

据印度报道,采用容易从海水中获得的氯化钠处理海洋锰结核的想法导致建议探索海洋锰结核电解氯化的可能性。复杂氧化矿石如海洋锰结核难以电解氯化。阳极极化研究表明,向矿体添加硫化钠,这个过程是可能进行的。为了证实硫化钠添加剂的有利影响.以及可使金属回收率达到令人满意的水平,已在隔膜电解槽中进行了电解氯化试     

矿产资源科学开采及其复杂性研究

在“碳达峰”、“碳中和”的目标背景下,绿色低碳、清洁高效成为资源开采的新要求,也对科学开采这一复杂系统问题的研究提出了新的方向。阐述了矿产资源开采理念的发展演化,综述了近年来国内外在科学开采方面的研究现状,构建了安全、高效、绿色、低碳、经济、科学管理“六位一体”的科学开采体系,丰富了科学开采的内涵和框架。从复杂科学问题的判断标准、科学开采体系的特征两方面进行推断,得出科学开采属于复杂问题,承载科学开采复杂问题的系统是复杂系统。以复杂科学的思路研究科学开采的复杂性,构建科学开采复杂系统模型,从顶层设计、中层连接和底层基础3个层次思考了实现科学开采的新途径,为实现矿产资源的科学开采提供了新的发展方向。     

Of Perspectives,Issues, and Politics in Materials Technology

Recognizing the pervasive importance of materials science and engineering (MSE) to practically every facet of man’s life, this lecture takes a broad view of the origin and technical trends and achievements in MSE, briefly reviewing its history and relationship to society over many millennia, to the present day, with specific examples. Major emphasis, however, is placed on modern MSE as related to current national issues, using as illustrations of the latter natural resources, industry and the economy, research and development, education, and technology transfer. The discussion of these areas leads to consideration of the role of the Federal Government and the importance of and need for a coherent national policy to deal with critical issues, many of which are listed herein. Some important steps by the Government fostering high level coordination as well as cooperation among government, industry, and academe are cited. Having thus illustrated the pervasive and vital impact of MSE on society, and its current esteemed recognition and position of influence, the lecture concludes that in this period of global change — social, economic, and technological — there is a challenge to MSE to respond beneficially to societal needs more than ever before. The opportunity and mechanisms now exist. Greater participation in the public and political arenas, with mutual education, is indicated. NATHAN E. PROMISEL received his Bachelor of Science and Master of Science Degree at the Massachusetts Institute of Technology, did his doctorate work at Yale University, and received an Honorary Doctor of Engineering Degree at Michigan Technological University. He became Assistant Lab Director at International Silver Company, leaving in 1940, and Chief Materials Scientist and Engineer (aeronautics and weapons) and Materials Research Coordinator for the Department of the Navy, leaving in 1966. He is presently an International Consultant. Dr. Promisel has been a long-time member of the National Materials Advisory Board of the National Academies of Science and Engineering, and from 1966 to 1974 was its Executive Director. He was also a Member of the Office of Technology Assessment (Congress) Materials Advisory Committee, as well as Chairman or Member of numerous other Government and public technical groups. These included being Chairman of the U.S. Group for the Science Exchange Program with the U.S.S.R., for materials and electrometallurgy, and serving as Chairman of the NATO Aerospace Research Group (Materials and Structures). Dr. Promisel is a member of the National Academy of Engineering; Past President, Fellow, and Honorary Member, American Society for Metals; Past President and Founding Member of the Federation of Materials Societies; Honorary Member of AIME, ASTM, and SAE (Materials Division); Fellow of British Institute of Metals and SAMPE. He has presented distinguished lectures to The Electrochemical Society and ASTM. Dr. Promisel has received numerous awards and is the holder of two patents. He has written 65 technical papers and has been the author, contributor, or editor of eight books.     

锂离子电池安全性研究进展

综述了近年来电解液的热稳定性影响因素、热失控过程及产物成分、单体及电池组燃爆安全性、灭火措施的研究进展.指出电解液的热稳定性受锂盐和有机溶剂的共同影响,当电池内部温度达到120℃左右时放热反应开始出现,在热量持续积累的情况下热失控将自发进行,同时产生氢气和烷烃类具有燃烧爆炸危险的气体产物.与二氧化碳和干粉类灭火剂相比,七氟丙烷和水的灭火效果较好.最后对锂离子电池的应用前景做了展望,提出了不同滥用条件下的热失控过程、热失控产物生成机理,指出开发新型电解液和寻求高效灭火介质是今后研究的方向.      

空间机械臂在轨插、拔孔操作基于力/位姿跟踪指数型阻抗控制

讨论了空间机械臂在轨插、拔孔操作的阻抗控制问题。为此,结合系统动量守恒关系,空间机械臂替换部件末端输出插、拔孔主动力与孔内所受摩擦阻力作用关系,以及第二类拉格朗日方程,推导得到了载体位置、姿态均不受控制情况下,空间机械臂在轨插、拔孔操作过程系统动力学方程。同时,根据相关操作控制系统设计需要,利用系统位置几何关系分析、建立了空间机械臂替换部件末端相对基联坐标系的相对运动雅可比关系。之后,由空间机械臂替换部件末端位姿与末端输出插、拔孔主动力之间的动态关系并结合阻抗控制原理,建立了二阶线性阻抗模型。在上述工作基础上,针对空间机械臂在轨插、拔孔操作过程同时存在运动学与动力学不确定性的情况,设计了空间机械臂替换部件末端力/位姿跟踪指数型阻抗控制策略;并通过李雅普诺夫理论,证明了控制系统的稳定性。提到的控制策略具有结构简单、收敛速度快、稳定性好的特点。系统数值仿真,验证了上述控制策略的有效性。      

The urgent need to improve health care quality. Institute of Medicine National Roundtable on Health Care Quality

OBJECTIVE: To identify issues related to the quality of health care in the United States, including its measurement, assessment, and improvement, requiring action by health care professionals or other constituencies in the public or private sectors. PARTICIPANTS: The National Roundtable on Health Care Quality, convened by the Institute of Medicine, a component of the National Academy of Sciences, comprised 20 representatives of the private and public sectors, practicing medicine and nursing, representing academia, business, consumer advocacy, and the health media, and including the heads of federal health programs. The roundtable met 6 times between February 1996 and January 1998. It explored ongoing, rapid changes in health care and the implications of these changes for the quality of health and health care in the United States. EVIDENCE: Roundtable members held discussions with a wide variety of experts, convened conferences, commissioned papers, and drew on their individual professional experience. CONSENSUS PROCESS: At the end of its deliberations, roundtable members reached consensus on the conclusions described in this article by a series of discussions at committee meetings and reviews of successive draft documents, the first of which was created by the listed authors and the Institute of Medicine project director. The drafts were revised following these discussions, and the final document was approved according to the formal report review procedures of the National Research Council of the National Academy of Sciences. CONCLUSIONS: The quality of health care can be precisely defined and measured with a degree of scientific accuracy comparable with that of most measures used in clinical medicine. Serious and widespread quality problems exist throughout American medicine. These problems, which may be classified as underuse, overuse, or misuse, occur in small and large communities alike, in all parts of the country, and with approximately equal frequency in managed care and fee-for-service systems of care. Very large numbers of Americans are harmed as a direct result. Quality of care is the problem, not managed care. Current efforts to improve will not succeed unless we undertake a major, systematic effort to overhaul how we deliver health care services, educate and train clinicians, and assess and improve quality.     

The Free Trade Agreement and environmental health in Mexico

This work offers an overview of the state of the art and future state of environmental health in our country from a viewpoint of the impact of the commercial opening established in the Free Trade Agreement among Mexico, the USA, and Canada. In the first section of this work, we analyze the expected economic changes resulting from the implementation of the FTA and foretells the way in which those changes will influence the present environmental and epidemiologic profiles of this country in the medium and long term. The main changes predicted by the analysis are, in the epidemiologic context, the acceleration of the transference of occupational, consumption, environmental and population risks, characteristic of industrialized countries, to the country's polarized epidemiologic profile; and, in the environmental context, a transition consisting of a broadening and composition of the spectrum of pollutants, including and important lagging of bacteriologic control. The second section offers an analysis of the predicted response capacity facing the new environmental risk dynamics in the country, encompassing regulation, normativeness and enforcement of environmental and consumer protection, as well as obstacles found in health services to the implementation of surveillance, detection and treatment of health damages caused by environmental factors. The analysis of the organized social response to these problems discloses a relative flexibility of the normativeness and enforcement functions in comparison with our northern neighbors, a paramount factor for the possible transference of environmental risks, as well as the informational and research deficiency about environmental issues, basic elements for sustaining environmental health in the country, aiming at speeding up the development and transference of technologies for prevention, detection and management of environmental risks in the country, drawing upon the systematization of our experience and that of our neighbors. This speeding process ought to match, in the medium term, the velocity of risk transference produced by the commercial opening. In this way, the commercial integration of North America will become a favorable context for the development of the environmental health infrastructure of the country.     

Long-chain alkenes of the haptophytes Isochrysis galbana and Emiliania huxleyi

The gene families encoding the immunoglobulin variable regions of heavy (VH) and light (VL) chains in vertebrates are composed of many genes. However, the gene number and the extent of diversity among VH and VL gene copies vary with species. To examine the causes of this variation and the evolutionary forces for these multigene families, we conducted a phylogenetic analysis of VH and VL genes from the species of amniotes. The results of our analysis showed that for each species, VH and VL genes have the same pattern of clustering in the trees, and, according to this clustering pattern, the species can be divided into two groups. In the first group of species (humans and mice), VH and VL genes were extensively intermingled with genes from other organisms; in the second group of species (chickens, rabbits, cattle, sheep, swine, and horses), the genes tended to form clusters within the same group of organisms. These results suggest that the VH and VL multigene families have evolved in the same fashion: they have undergone coordinated contraction and expansion of gene repertoires such that each group of organisms is characterized by a certain level of diversity of VH and VL genes. The extent of diversity among copies of VH and VL genes in each species is related to the mechanism of generation of antibody variety. In humans and mice, DNA rearrangement of immunoglobulin variable, diversity, and joining-segment genes is a main source of antibody diversity, whereas in chickens, rabbits, cattle, sheep, swine, and horses, somatic hypermutation and somatic gene conversion play important roles. The evolutionary pattern of VH and VL multigene families is consistent with the birth-and-death model of evolution, yet different levels of diversifying selection seem to operate in the VH and VL genes of these two groups of species.     

The lymphatic vessels and the so-called "lymphatic stomata" of the diaphragm: a morphologic ultrastructural and three-dimensional study

We studied the absorbing peripheral lymphatic vessel with the light microscope, the transmission electron microscope, the scanning electron microscope, and three-dimensional models of the diaphragm of several rodents and insectivores under normal and experimental conditions (lymphatic stasis and dehydration). To clarify the delicate and complex mechanism that permits drainage of the abdominal cavity contents into the lymphatic circulatory system, we introduced Polystyrene latex spherules, China ink, and Trypan blue into the abdominal cavities. After anatomical comparisons of the superficial and deep networks of absorbing peripheral lymphatic vessels at the tendinous and muscular portions of the diaphragm and after classification of lymphatic vessels into absorbing and conducting functions, we examined the stomata, which, owing to morphologic and topographic findings, we defined as stable structures. Furthermore, we observed that the stomata and submesothelial connective channel are fundamental elements that facilitate the flow of the corpuscular and liquid contents of the peritoneal cavity to the submesothelial absorbing lymphatic vessel wall. Also, we underlined that the genesis of the connective channel depends on the secondary cytoplasm extensions of two distinct adjacent endothelial cells, which, to facilitate the flow of the absorbed abdominal contents, completely coat this channel. Additionally, our observations illustrate that the secondary cytoplasm extensions do not engage in continuous relationships with the basal lamina of the mesothelium and with the margins of the stoma, and, hence, the hypothesis of "lymphatic stomata" as an expression of the anchoring of the borders of the open interendothelial junctions to the orifice margins of the stoma cannot be confirmed. Moreover, we describe the presence and formation of intraendothelial channels in the lymphatic endothelial wall. We affirm that this morphological entity is a dynamic unit, because its numerical density varies according to different physiological and experimental conditions to degrees of hydrostatic and colloidal osmotic pressure and, perhaps, also to the particular characteristics of the substances that the connective channel liberates into the endothelial wall of the lymphatic vessel. In conclusion, we affirm that the absorbing peripheral lymphatic vessels of the diaphragm, by way of intraendothelial channel formations, membrane diffusion, and the vesicular path of the endothelial cells, constitute the fundamental draining elements for the corpuscular and liquid contents of the abdominal cavity.     

基于灰色关联分析的三山岛金矿绿色开采技术优先级评价

推进矿山绿色开采是一项长期而复杂的系统工程,而绿色开采技术的应用面临着投资周期长和成本高等问题,鉴于此,开展绿色开采技术优先级评价,有助于指导矿山决策部门的工作,实现绿色开采有序化,降低投资成本。在构建三山岛金矿绿色开采技术体系的基础上,提出了一种灰色关联分析优化模型,并利用该模型对绿色开采技术进行评价分析。首先,构建了层次化绿色开采技术评价指标体系,系统地反映了各因素对绿色开采技术的影响;然后,利用AHP法和熵值法组合赋权,弥补了主观赋权法和客观赋权法的不足,使赋权趋于合理化;最后,分别应用3种赋权方法的优化模型和传统等权法模型对三山岛金矿绿色开采技术的绿色度进行量化分析,并对比分析了4种模型的关联度计算结果,最终得出三山岛金矿绿色开采技术推进的优先级。     

Evaluation of the allergenicity of spore and mycelia extracts of Pisolithus tinctorius

The antigenic and allergenic chemical analysis of spore and mycelia extracts of Pisolithus tinctorius was carried out. The spores were collected from basidiocarps in plantations of Eucalyptus spp and the mycelia from culture in MNM medium. With basis on the fungus growth curve, the mycelia masses were obtained after 10, 20, 30, and 40 days of incubation, which correspond, respectively, to the beginning, middle and end of the log phase, and beginning of the decline phase. The mycelia masses, together with the spores, were submitted to the action of three extractors (Coca, Tris-HCl, and ammonium bicarbonate). The contents of carbohydrates and proteins were determined. The SDS-PAGE electrophoretical analysis revealed separate fractions in these extracts, besides common fractions, in function of cultivation time and extraction methods. The selected extracts for the allergic tests were the ones with the highest number of fractions. The prick-tests were conducted in 374 patients--rural workers, eucalyptus plantation workers, and college students. The positivity to the "prick test" with the antigenic extract of P. tinctorius was, respectively, 3.78%, 28.20% and 6.40%. Most prick-test positive patients (82.75%) also presented symptoms of respiratory allergy (asthma and rhinitis). There was no reactivity difference when the spore and mycelia extracts were employed. The analysis of the positive patients' sera revealed the presence of IgE specific to the P. tinctorius antigens. Since Pisolithus tinctorius is found as mycorrhiza of Eucalyptus spp, and this plant is used in reforestation in most countries, the importance of that fungus should be regarded as a possible cause of respiratory allergies, especially in occupationally exposed workers.