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1.
Following colonisation of South America by the Spanish, many new naturally occurring substances were sent to Europe. One of these was the silvery, unreactive metal, platinum, discovered in New Grenada in the mid-eighteenth century. It was often found in granular form, associated with gold, and the challenge to chemists was to refine it, produce it as wire or sheet, and determine its chemical properties. This interested the professor of chemistry at the University of Edinburgh, Joseph Black, who was able to obtain samples from London-based Spanish contacts, particularly Ignacio Luzuriaga. This paper examines how Black transmitted his knowledge of the metal to large numbers of students attending his annual course.  相似文献   

2.
In this “perspective” paper, some of the landmark discoveries and accomplishments of the past within the field of fluorine chemistry will be reviewed. Within this review, the dramatic changes (and growth in size and diversity) that the field has undergone, particularly over the last 50 years, will also be discussed. Then finally, where fluorine chemistry is and where it appears to be going will be briefly discussed. The future of fluorine chemistry indeed appears bright, with fluorine chemistry set to play a role, and usually a significant role in most important areas of technology of the 21st century. New perspectives will be required, but then, fluorine chemists have been providing such “new perspectives” to this ever-changing field for the last 75 years.  相似文献   

3.
对催化不对称合成的重大贡献——2001年诺贝尔化学奖   总被引:2,自引:0,他引:2  
本年度诺贝尔化学奖授予了美国化学家诺尔斯博士与日本化学家野依良治教授(合占1/2)和美国化学家沙普利斯教授(占1/2),以表彰他们在发展催化手性/不对称合成的新方法技术及其应用于工业生产研究领域中的开创性贡献。在20世纪有机化学的发展中,最重要的突破之一是催化手性/不对称合成的研究成功。本文对催化手性/不对称合成的基本原理、应用与进展及3位杰出科学家的贡献做了简明扼要介绍。  相似文献   

4.
The paper surveys how chemistry has developed over the past two centuries starting from Lavoisier’s classification of the chemical elements at the end of the eighteenth century; the subsequent development of the atomic–molecular model of matter preoccupied chemists throughout the nineteenth century, while the results of the application of quantum theory to the molecular model has been the story of this century. Whereas physical chemistry originated in the nineteenth century with the measurement of the physical properties of groups of chemical compounds that chemists identified as families, the goal of chemical physics is the explanation of the facts of chemistry in terms of the principles and theories of physics. Chemical physics as such was only possible after the discovery of the quantum theory in the 1920’s. By then the first of the sub‐atomic particles had been discovered and seemingly it is no longer possible to discuss chemical facts purely in terms of atoms and molecules – one has to recognize the electron and the nucleus, the parts of atoms. The combination of classical molecular structure with the quantum properties of the electron has given us a tremendously successful account of chemistry called ‘quantum chemistry’. Yet from the perspective of the quantum theory the deepest part of chemistry, the existence of chemical isomers and the very idea of molecular structure that rationalizes it, remains a central problem for chemical physics. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

5.
组合化学——合成化学领域的一次革命   总被引:5,自引:0,他引:5  
柏旭 《化学通报》2001,64(12):762-768
组合化学是近十几年逐渐发展成熟起来的一个学科,它从根本上改变了化学家、生物学家以及相关学科研究人员的思维和研究方式,对科学的发展产生了革命性的影响。组合化学从创立起就与工业应用紧密联系在一起,它带动了包括新药发明和新材料研制在内的一系列高新科技产业的发展。下面简述了组合化学的起源与发展、研究方法及其对相关学科的影响和技术前景。  相似文献   

6.
The classical Kukhtin-Ramirez adducts, namely the 1:1 adducts of trivalent phosphorus reagents and 1,2-dicarbonyl compounds, were found more than half a century ago. Recently this family of organophosphorus compounds has regained remarkable interest from organic chemists. Relevant investigations have unveiled that Kukhtin-Ramirez adducts possess rich and appealing reactivity, particularly serving as nucleophiles, carbene surrogates or 1,1-dipoles in a series of organic reactions including insertion reaction, cyclopropanation reaction and formal (1?+?4) annulation reaction. This digest aims to summarize such encouraging advances. To give the readers a complete portrait about the chemistry of Kukhtin-Ramirez adducts, the early reports are also briefly discussed.  相似文献   

7.
The aims, curricula, and types of professional training of analytical chemists in classical universities are considered. Based on the data of a questionnaire filled at by the members of of analytical chemistry departments, an optimum set of special courses was proposed for the specialty analytical chemistry. An alternative set of special courses corresponding to the applied approach to training analytical chemists is sometimes taught to students of new specialties. A compromise between the two approaches is the introduction of additional educational programs.  相似文献   

8.
21世纪理论化学的挑战和机遇   总被引:14,自引:1,他引:14  
徐光宪 《结构化学》2002,21(5):463-469
本文是2002年7月在长春召开的第八届全国量子化学学术会议上的大会发言。内容如下:(1)20世纪的化学取得了辉煌的成就,应该获得社会的认同。(2)20世纪发明了七大技术,第一是合成化学技术。(3)21世纪的化学面临四大难题,期待我们去解决。(4)理论化学家应该深入交叉学科领域,拓展研究阵地。  相似文献   

9.
Beretta M 《Ambix》2011,58(3):257-276
Throughout the nineteenth century and the first half of the twentieth century, many distinguished chemists attributed an important, at times crucial, role to the historical narrative. When the first professional histories were published during the nineteenth century, their role was intimately interwoven with the identity of chemistry, a science that in spite (or because) of its rapidly growing importance in the industrialisation of Europe, did not have the same reputation as either the exact sciences or the medical-biological disciplines. With the works by Berthelot, Lippmann, and Mieli, the history of chemistry focused on its rich and varied documentary sources. The histories of chemistry produced during this period set the ground for a variety of approaches that reflect, to a large degree, the main currents of old and recent history of science. Moreover, historians of chemistry, both continental and Anglo-American, had a prominent role in establishing the history of science as an independent discipline.  相似文献   

10.
Alan M. Bond   《Analytica chimica acta》1999,400(1-3):333-379
The millennium being celebrated this year coincides with the 200th anniversary of the birth of practical electrochemistry made possible via Volta’s publication of the battery in the year 1800. The analytical chemists at the beginning of the 19th century were very quick to take advantage of this newly reported device and the first qualitative electrochemical determination of copper rapidly followed this pioneering discovery. In the last 200 years, electrochemical analysis, in its various forms, has been undertaken routinely in countless laboratories all over the world. However, in view of the long and distinguished history of the discipline, and some limitations that have been identified at the time of the celebration of the millennium, electrochemical analysis is regarded in some quarters as being a mature and conservative discipline whose importance in the future, when faced with severe competition from newly emerging alternative analytical techniques, is somewhat unclear. In this paper, an overview of past and present developments in electroanalytical chemistry and the possible future status of the technique is presented. In particular, emphasis is given to describing applications relevant to the also very mature field of electrowinning of zinc from plant electrolyte. This overview encompasses the author’s 25 years’ experience in developing polarographic, stripping voltammetric, adsorptive stripping voltammetric and ion-selective electrode (ISE) methods of analysis in on-line, on-stream and off-line modes for the determination of elements such as Cd, Pb, Ge, Sb (oxidation states (III) and (V)), Co, Ni, Zn, Fe, (oxidation states (II) and (III)), Tl, As (total) and Cu in zinc plant electrolyte. Developments that may contribute to an important future for analytical voltammetry are also considered as are limitations that could inhibit the extent of practical use of these electroanalytical techniques in the 21st century.  相似文献   

11.
This paper argues that the field of chemistry underwent a significant change of theory in the early twentieth century, when atomic number replaced atomic weight as the principle for ordering and identifying the chemical elements. It is a classic case of a Kuhnian revolution. In the process of addressing anomalies, chemists who were trained to see elements as defined by their atomic weight discovered that their theoretical assumptions were impediments to understanding the chemical world. The only way to normalize the anomalies was to introduce new concepts, and a new conceptual understanding of what it is to be an element. In the process of making these changes, a new scientific lexicon emerged, one that took atomic number to be the defining feature of a chemical element.  相似文献   

12.
Amy Fisher 《Ambix》2018,65(2):169-189
As a professor of chemistry at the University of Pennsylvania, Robert Hare actively shaped early American science. He participated in a large network of scholars, including Joseph Henry, François Arago, and Jacob Berzelius, and experimented with and wrote extensively about electricity and its associated chemical and thermal phenomena. In the early nineteenth century, prominent chemists such as Berzelius and Humphry Davy proclaimed that a revolution had occurred in chemistry through electrical research. Examining Robert Hare’s contributions to this discourse, this paper analyzes how Hare’s study of electricity and the caloric theory of heat led him to propose a new theory of galvanism. It also examines the reception of Hare’s work in America and Great Britain, highlighting the contributions of early American chemists to the development of electrochemistry.  相似文献   

13.
从研究分析化学的历史发展入手,以大量历史事实为根据,指出分析化学曾经历过两次重大变革。第一次变革(19世纪末至20世纪初)使分析化学从分析化学家的技艺发展为科学;第二次变革(20世纪70年代迄今)则使分析化学进入了分析化学家重新当家作主的、欣欣向荣的“第二个春天”。  相似文献   

14.
Among the fundamental transformations in the field of synthetic organic chemistry, transition-metal-catalyzed reactions provide some of the most attractive methodologies for the formation of C-C and C-heteroatom bonds. As a result, the application of these reactions has increased tremendously during the past decades and cross-coupling reactions became a standard tool for synthetic organic chemists. Furthermore, a tremendous upsurge in the development of new catalysts and ligands, as well as an increased understanding of the mechanisms, has contributed substantially to recent advances in the field. Traditionally, organic reactions are carried out by conductive heating with an external heat source (for example, an oil bath). However, the application of microwave irradiation is a steadily gaining field as an alternative heating mode since its dawn at the end of the last century. This tutorial review focuses on some of the recent developments in the field of cross-coupling reactions assisted by microwave irradiation.  相似文献   

15.
We review the known chemistry of the cyaphide ion, (C≡P). This remarkable diatomic anion has been the subject of study since the late nineteenth century, however its isolation and characterization eluded chemists for almost a hundred years. In this mini-review, we explore the pioneering synthetic experiments that first allowed for its isolation, as well as more recent developments demonstrating that cyaphide transfer is viable in well-established salt-metathesis protocols. The physical properties of the cyaphide ion are also explored in depth, allowing us to compare and contrast the chemistry of this ion with that of its lighter congener cyanide (an archetypal strong field ligand and important organic functional group). Recent studies show that the cyaphide ion has the potential to be used as a versatile chemical regent for the synthesis of novel molecules and materials, hinting at many interesting future avenues of investigation.  相似文献   

16.
The increasing control that synthetic chemists are able to exert over molecular architecture is allowing the design and preparation of macromolecular and polymeric systems of unprecedented sophistication. In form and function, synthetic polymers are able to mimic many biological polymers, in effect ‘blurring the boundaries’ between the worlds of artificial and natural materials. In this review, some key examples from the merging interface between synthetic and natural polymers are considered, and illustrations of both ‘bio-inspired’ synthetic macromolecular chemistry and new directions in polymer materials are given.  相似文献   

17.
The steps in the development of analytical chemistry and the organization of the school of analytical chemists in the city of Perm are considered. The role of G.G. Kobyak, the first head of the Division of Analytical Chemistry, in the organization of scientific research at the division, the selection of division staff, and the subsequent continuity of the formation of the division and the school of analytical chemists at Perm State University is outlined.  相似文献   

18.
The use of open-access mass spectrometry to monitor synthetic chemistry reactions, and also the integrity and purity of new chemical entities, has been a part of the medicinal chemist's tool-box for more than 5 years. Originally in our group at Wyeth Research there were two open-access methods available to the chemists, flow injection analysis (FIA) and liquid chromatography/mass spectrometry (LC/MS). The FIA method was approximately 3 min long, while the LC/MS method was approximately 20 min long (including an 8 min gradient). Within the first 2 years, the total number of open-access analyses increased by approximately 125%. It is interesting, however, that the number of LC/MS analyses increased by more than 285%. This is attributed to the fact that the chemists began using the LC/MS data to monitor reactions and also to check final product integrity and purity. In addition, the number of chemists performing parallel synthesis reactions has increased; thus, individual chemists can produce sample sets of up to 100 vials. This paper describes the implementation of new methodology, which accommodates the need for much faster run times and also the ability to acquire alternating positive and negative ion spectra within the same run. In addition, the instrument has been configured to e-mail the resulting processed data report to the submitting chemist. Several methods have been developed, including structure elucidation using in-source collision-induced dissociation (CID) and night-time analysis. The LC/MS methods for this system are described herein and are applicable to both industrial and academic synthetic chemistry optimization efforts.  相似文献   

19.
“失配的Lewis对”(Frustrated Lewis Pairs,FLPs)作为有机化学领域的新概念,在非金属活化H2,CO2和NH3等小分子方面的研究和应用格外引人注目.以“失配的Lewis对”为催化剂,直接以氢气作为氢源,非金属催化氢化还原醛、烯胺、亚胺、腈和二氧化碳等获得了很好的结果.手性“失配的Lewis对”(Chiral Frustrated Lewis Pairs,Chiral FLPs)在不对称催化氢化还原亚胺的反应中也呈现出较高的光学选择性,产物胺的对映体过量最高达83% ee.综述了近几年“失配的Lewis对”在非金属催化氢化研究领域的进展情况.  相似文献   

20.
Selenium-based methods have developed rapidly over the past few years asnd organoselenium chemistry has become a very useful tool in the hands of synthetic chemists. The different reactivity of selenium-containing compounds in contrast to the sulfur analogues has led to versatile and new synthetic methods in organic chemistry. Various functionalities can be selectively introduced into complex molecules under very mild reaction conditions. In this review, the principles of organoselenium chemistry are traced back to their origins and are highlighted with respect to stereoselective synthesis. The unique properties of selenium allow the development of new and highly selective transformations, which can be employed subsequently in new routes for the synthesis of versatile chiral building blocks and for natural product synthesis.  相似文献   

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