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1.
Summary.  Experimental solubility data for metals and non-metallic substances in liquid alkali metals have been collected from literature, critically evaluated, and selected for recommendation. Sometimes results for a selected system at a selected temperature vary over more than an order of magnitude. This is not uniquely connected with a poor precision of the measurements. Some impurities may spectacularly modify the solubilities and, moreover, definition of a saturating solute phase is not always a simple task. Based on supplementary experiments one may explain several phenomena which often accompany dissolution processes. These accompanying processes are essentially the same as those frequently observed in solution chemistry. Received February 3, 2000. Accepted (revised) May 8, 2000  相似文献   

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液相组合化学研究进展   总被引:3,自引:0,他引:3  
综述了液相组合化学的发展及其在有机合成中的应用。  相似文献   

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《Ambix》2013,60(2):172-191
Abstract

When gold became considered as a precious metal for decorative purposes and later for coinage, attempts at producing imitations soon began to appear. There were two motives behind this activity: to make a metal that could pass as gold, and to quite openly imitate this precious metal for people who could not afford true gold. Imitation gold was produced by metallurgists, and later also by alchemists. This paper is about gold imitations that did not contain any precious metal. Gold-like alloys of silver are thus excluded. An attempt is further undertaken to classify into separate groups the various gold imitations that have appeared in different cultures throughout time, with an emphasis on brass as a typical imitation of gold.  相似文献   

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This paper mainly introduces the role of isotopes in exploring the origin of life and related principles. In addition, by reviewing the discovery history of isotopes and summarizing the contributions of major scientists, we hope to show the general process of science developments to the public.  相似文献   

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In this perspective, we briefly present the historical context in which, fifty years ago, dielectric continuum models were developed to incorporate solvent effects into quantum mechanical calculations. Since the first self-consistent-field equations including the solvent electrostatic potential (or reaction field) were reported in 1973, continuum models have become extremely popular in the computational chemistry community and are routinely used in a very wide range of applications.  相似文献   

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An historical view of solution chemistry of Japan is described for a wide range of fields of solution chemistry, which relates to physical chemistry, inorganic chemistry, analytical chemistry, biochemistry and bioinorganic chemistry, and colloid and polymer chemistry. The works by pioneers of Japanese solution chemistry are introduced, some of which are not well recognized internationally. The influences of Japanese solution chemistry on the world and vice versa are discussed on the basis of a rather personal viewpoint. Recent activities of Japanese solution chemists at the national and international levels are also reviewed.  相似文献   

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Meeting Notice

XXII International Conference on Solution Chemistry  相似文献   

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A historical view of the solution chemistry of Japan is described for a wide range of fields of solution chemistry, which relates to physical chemistry, inorganic chemistry, analytical chemistry, biochemistry and bioinorganic chemistry, and colloid and polymer chemistry. The works by pioneers of Japanese solution chemistry are introduced, some of which are not well recognized internationally. The influences of Japanese solution chemistry on the world and vice versa are discussed on the basis of a rather personal viewpoint. Recent activities of Japanese solution chemists at the national and international levels are also reviewed.  相似文献   

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普通化学在石油工程专业本科教学中发挥着重要的作用。以水溶液化学一章为例,探讨了在非化学专业讲授该课程的方法。认为教学中首先必须注重知识体系的完整性,将基础理论讲透,并在各个章节中不断应用、强化这些重要的理论。其次,理论教学必须紧扣石油工程的专业背景,通过将工程领域的具体应用穿插到理论学习的全过程中,有助于提高学生用化学的方法分析工程问题的能力。再次,教学形式和考查方式的改革应以提高学生学习兴趣,培养分析问题、解决问题的能力为目标,采用灵活生动的教学形式和多角度的考查方式已证实是实现这一目标的有效途径。  相似文献   

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黄咏梅 《化学教育》2007,28(2):40-41
马克思曾经说过:"一种科学只有成功地运用了数学时,才算达到真正完美的地步."现代科学的数学化,不仅普遍体现在自然科学中,也表现在数学向着社会科学渗透.运用数学手段解决化学问题不仅使我们的解题能够更加准确、简便,还使我们能够更加精确简明地表达化学理论,更重要的是通过这样的解题途径和方法,对培养学生的逻辑思维,创新思维和求异思维及解题能力和技巧都具有深远意义;学生对学科间知识的相互渗透也有了更深层次的理解,以便他们在今后的学习中能做到知识的相互迁移和灵活运用.本文仅通过几例对化学解题中的数学构造法作了一些尝试.  相似文献   

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JackHolbrook 《化学教育》2002,23(12):11-14,33
While chemistry is popular for children of primary school age,its popularity drops dramatically in secondary schools,A potential solution to address this is to recognise the need for greater relevance-relevance to the curriculum,to the needs of society and,in the eyes of the students.The paper tries to puts forward a rethink of the philosophy for school chemistry education,based on the underlying belief that chemistry education is an integral part of education.The target is labelled scientific and technological literacy for all (STL),STL rejects the notion that chemistry is taught solely to acquire tha abilities to be a scientist and supports the vision of a single curriculum goal,applicable to all students.Besides being a philosophy,STL is also a teaching approach.This approach is to initiate the teaching of chemistry topics,starting from a carefully chosen society perspective and to introduce the conceptual learning on a need-to-know basis.A limitatioin is the professional development of teachers,Suggestion for overcoming this involve workshop on materials development.Aconcern is expressed in cases where teachers make use of ready-made teaching materials(a common practice),without first gaining an understanding and an appreciation of the intended philosophy related to these materials.  相似文献   

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王稼国  荆西平 《化学通报》2018,81(3):278-287
金属卤化物水溶性规律一直是困扰大一新生的问题。本文从原子结构和分子结构出发归纳了金属卤化物的化学键,再根据化学键的强弱分析其水溶方式,同时配以热力学数据讨论了其溶解过程中的能量变化,最后归纳出了金属卤化物的水溶性规律。  相似文献   

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In this work, we presented the solubilities of isobutane and cyclopropane in 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([HMIM][Tf2N]) and trihexyl tetradecylphosphonium bis(2,4,4-trimethylpentyl) phosphinate ([P(14)666][TMPP]) from T = (302 to 344) K up to 1.16 MPa. Henry’s constants for isobutane and cyclopropane in [HMIM][Tf2N] and [P(14)666][TMPP] were calculated from experimental results. Solubilities of isobutane and cyclopropane in [HMIM][Tf2N] are apparently smaller than those in [P(14)666][TMPP]. The effects of temperature, pressure and the number of carbon atoms in the hydrocarbons on the solubility were investigated in detail. A modified Krichevsky–Kasarnovsky equation was successfully applied to correlate the experimental results. The mean absolute relative deviations and the maximum absolute relative deviations are less than (2.4 and 4.6)%, respectively.  相似文献   

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Summary.  The evaluation of mutual solubility data for systems water with n-alkanes, isoalkanes, and cycloalkanes along the three phase line is reported and a formula for the prediction of solubility of alkanes in water is developed. Then a cubic equation of state with an added term, which accounts for hydrogen bonding is used for correlation of liquid–liquid equilibrium data and for prediction of solubility of water in hydrocarbons using alkane in water solubility data. Comparison of the predicted and experimental solubilities is performed using all accessible experimental data. With this approach it is possible to predict the solubilities of water in alkanes with good accuracy over the temperature range up to about 20 K below critical temperature. Solubility of alkanes in water can also be calculated using experimental data for solubility of water in alkanes but results of these calculations are more sensitive to experimental errors of the data. Corresponding author: E-mail: macz@ichf.edu.pl Received August 5, 2002; accepted (revised) September 13, 2002 Published online March 13, 2003 RID="a" ID="a" Dedicated to Prof. Dr. H. Gamsj?ger on the occasion of his 70th birthday anniversary  相似文献   

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