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1.
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   

2.
全球信息网WWW上的化学资源   总被引:4,自引:0,他引:4  
文献查阅是化学工作者必须掌握的基本技能之一.随着计算机网络技术的迅速发展,利用全球信息网WWW浏览和获取化学信息已成为查阅化学文献最重要的方法之一.在化学工作者中普及万维网WWW查阅各类化学信息和获取化学资源的方法是非常重要的.作者简要叙述WWW的基本原理和通过WWW获取化学信息和化学资源的方法,并给出部分Internet化学资源.  相似文献   

3.
4.
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   

5.
This article examines the role of the blowpipe in the discovery process of the disproportionately large number of new elements found by Swedish chemists during the eighteenth century and into the nineteenth. While individual chemists abroad used versions of the tool, in Sweden alone its use was ubiquitous across the chemical and mineralogical research community, and its consistently simple handheld design made basic dry chemical analysis quick, cheap, and portable. This shared use of the tool was crucial to the development of the mineral analysis projects that uncovered new substances, first by enabling the adoption of a system defining minerals by their chemical components and mineralogy by chemical analysis, and second by providing a simple and practical method for that analysis that facilitated collaboration across institutions, physical distance, and time.  相似文献   

6.
After reviewing the field of graphical bioinformatics, we have selected two dozen of the most significant publications that represent milestones of graphical bioinformatics. These publications can be viewed as forming the backbone of graphical bioinformatics, the branch of bioinformatics that initiates analysis of DNA, RNA, and proteins by considering various graphical representations of these sequences. Graphical bioinformatics, a division of bioinformatics that analyzes sequences of DNA, RNA, proteins, and proteomics maps by developing and using tools of discrete mathematics and graph theory in particular, has expanded since the year 2000, although pioneering contributions date back to Hamory (1983) and Jeffrey (1990). We chronologically follow the development of graphical bioinformatics, without assuming that readers are familiar with discrete mathematics or graph theory. Readers unfamiliar with graph theory may even have some advantage over those who have been only superficially exposed to graph theory, inview of wide misconceptions and misinformation about chemical graph theory among quantum chemists, physical chemists, and medicinal chemists in past decades. © 2013 Wiley Periodicals, Inc.  相似文献   

7.
The use of transition-metal complexes as reagents for the synthesis of complex organic compounds has been under development for at least several decades, and many extraordinary organic transformations of profound potential have been realized. However, adoption of this chemistry by the practicing synthetic organic chemist has been inordinately slow, and only now are transition-metal reagents beginning to achieve their rightful place in the arsenal of organic synthesis. Several factors contributed to the initial reluctance of synthetic organic chemists to use organometallic reagents. Lacking education and experience in the ways of elements having d electrons, synthetic chemists viewed organometallic processes as something mysterious and unpredictable, and not to be discussed in polite society. Organometallic chemists did not help matters by advertising their latest advances as useful synthetic methodology, but restricting their studies to very simple organic systems lacking any serious functionality (e.g., the “methyl, ethyl, butyl, futile” syndrome). Happily, things have changed. Organometallic chemists have turned their attention to more complex systems, and more recently trained organic chemists have benefited from exposure to the application of transition metals. This combination has set the stage for major advances in the use of transition metals in the synthesis of complex organic compounds. This review deals with one aspect of this area, the use of transition metals in the synthesis of indoles.  相似文献   

8.
Shortly before his death, Richard Bader commented in this Journal on the dichotomy that exists within chemistry and between chemists. We believe that the dichotomy results from different goals and objectives inherent in the chemical disciplines. At one extreme are designers who synthesize new molecules with interesting properties. For these chemists, the rationale underpinning molecular synthesis is far less important than the end product—the molecules themselves. At the other extreme are the chemists who seek a fundamental understanding of molecular properties. We suggest that the Quantum Theory of Atoms in Molecules, by virtue of the rich hierarchical structure inherent in the theory, offers a bridge through which to unite these two groups. However, if there is to be reconciliation, it falls to the theorists to develop “quantum mechanically” correct tools and concepts useful to the synthetic and applied chemist.  相似文献   

9.
This paper aims to connect philosophy of chemistry, green chemistry, and moral philosophy. We first characterize chemistry by underlining how chemists: (1) co-define chemical bodies, operations, and transformations; (2) always refer to active and context-sensitive bodies to explain the reactions under study; and (3) develop strategies that require and intertwine with a molecular whole, its parts, and the surroundings at the same time within an explanation. We will then point out how green chemists are transforming their current activities in order to act upon the world without jeopardizing life. This part will allow us to highlight that green chemistry follows the three aforementioned characteristics while including the world as a partner, as well as biodegradability and sustainability concerns, into chemical practices. In the third part of this paper, we will show how moral philosophy can help green chemists: (1) identify the consequentialist assumptions that ground their reasoning; and (2) widen the scope of their ethical considerations by integrating the notion of care and that of vulnerability into their arguments. In the fourth part of the paper, we will emphasize how, in return, this investigation could help philosophers querying consequentialism as soon as the consequences of chemical activities over the world are taken into account. Furthermore, we will point out how the philosophy of chemistry provides philosophers with new arguments concerning the key debate about the ‘intrinsic value’ of life, ecosystems and the Earth, in environmental ethics. To conclude, we will highlight how mesology, that is to say the study of ‘milieux’, and the concept of ‘ecumeme’ proposed by the philosopher and geographer Augustin Berque, could become important both for green chemists and moral philosophers in order to investigate our relationships with the Earth.  相似文献   

10.
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   

11.
Terahertz spectroscopy is only now beginning to make its transition from initial development by physicists and engineers to broader use by chemists, materials scientists and biologists, thanks to the increasing availability of commercial terahertz spectrometers. With the unique insights that terahertz spectroscopy can provide into intermolecular bonding and crystalline matter, it could prove to be an invaluable addition to the chemist's analytical toolset. This tutorial review aims to give an introduction to terahertz spectroscopy, its techniques, equipment, current applications and potential for the chemical sciences to a broad readership.  相似文献   

12.
Which country pays its chemists and chemical engineers the highest salaries? Where can I find a new job quickest? Which chemical sub‐discipline offers most jobs? Reliable answers for these and other questions have been derived from the first European employment survey for chemists and chemical engineers, which was carried out in 2013. Here we publish the first general evaluation of the results of this survey.  相似文献   

13.
Horrocks S 《Ambix》2011,58(2):150-170
This paper draws on evidence from a range of sources to consider the extent to which World War II served as a turning point in the employment opportunities open to women chemists in Britain. It argues that wartime conditions expanded women's access to some areas of employment, but that these opportunities represented, in many ways, an expansion of existing openings rather than wholly new ones, and not all of them proved permanent. Instead, women chemists benefited more permanently from increased state expenditure on higher education and on research and development after the war. This enabled some women to remain in what had originally been temporary wartime posts and others to secure employment in wholly new positions. Women were most successful in securing positions created by the expansion of state welfare and support for agriculture, but also found new employment opportunities as a result of the heavy investment in weapons development that accelerated with the advent of the Cold War. In higher education, an initial expansion of openings was not sustained, and the proportion of women in university chemistry departments actually fell during the second half of the 1950s. Industry presents a rather ambiguous picture, with many firms continuing to refuse to employ women chemists, whereas elsewhere they enjoyed enhanced opportunities and better salaries than those offered before the war. This did not mean, however, that women chemists received equal treatment to their male colleagues, and, despite the changes, they remained concentrated in subordinate positions and were expected to concentrate on routine work. Prospects in the 1950s were certainly better than they had been during the 1930s, but they remained strongly gendered.  相似文献   

14.
The present Review highlights the challenges and opportunities when using the combination CO2/H2 as a C1 synthon in catalytic reactions and processes. The transformations are classified according to the reduction level and the bond‐forming processes, covering the value chain from high volume basic chemicals to complex molecules, including biologically active substances. Whereas some of these concepts can facilitate the transition of the energy system by harvesting renewable energy into chemical products, others provide options to reduce the environmental impact of chemical production already in today's petrochemical‐based industry. Interdisciplinary fundamental research from chemists and chemical engineers can make important contributions to sustainable development at the interface of the energetic and chemical value chain. The present Review invites the reader to enjoy this exciting area of “catalytic chess” and maybe even to start playing some games in her or his laboratory.  相似文献   

15.
The chemical production of graphene as well as its controlled wet chemical modification is a challenge for synthetic chemists. Furthermore, the characterization of reaction products requires sophisticated analytical methods. In this Review we first describe the structure of graphene and graphene oxide and then outline the most important synthetic methods that are used for the production of these carbon‐based nanomaterials. We summarize the state‐of‐the‐art for their chemical functionalization by noncovalent and covalent approaches. We put special emphasis on the differentiation of the terms graphite, graphene, graphite oxide, and graphene oxide. An improved fundamental knowledge of the structure and the chemical properties of graphene and graphene oxide is an important prerequisite for the development of practical applications.  相似文献   

16.
Radialenes are alicyclic compounds in which every ring atom is sp2-hybridized and carries an exocyclic C? C double bond. Because of their unusual topology and electronic structures these hydrocarbons have aroused the interest of both preparative chemists and theoreticians. Although considerable progress has been achieved recently, directed and efficient syntheses of these molecules remain a challenge. The study of their chemical behavior offers vast opportunities. Very recently materials scientists have become interested in these unusual compounds in their search for organic conductors and ferromagnets.  相似文献   

17.
DNA (deoxyribonucleic acid) is the genetic material common to all of Earth’s organisms. Our biological understanding of DNA is extensive and well‐exploited. In recent years, chemists have begun to develop DNA for nonbiological applications in catalysis, encoding, and stereochemical control. This Review summarizes key advances in these three exciting research areas, each of which takes advantage of a different subset of DNA’s useful chemical properties.  相似文献   

18.
The de novo synthesis of small organic heterocyclic molecules has benefited from recent protocols for copper-facilitated additions of heteroatoms to alkenes, alkynes and arenes. This tutorial review summarizes a number of these recent contributions. Copper salts can facilitate bond formations due to their ability to serve as Lewis acids, oxidizing agents and transition metal catalysts. The current understanding of the mechanisms of these reactions is presented. This review should be of interest to chemists involved in the synthesis of heterocycles and those investigating transition metal facilitated reactions.  相似文献   

19.
I argue in the paper that classical chemistry is a science predominantly concerned with material substances, both useful materials and pure chemical substances restricted to scientific laboratory studies. The central epistemological and methodological status of material substances corresponds with the material productivity of classical chemistry and its way of producing experimental traces. I further argue that chemist??s ??pure substances?? have a history, conceptually and materially, and I follow their conceptual history from the Paracelsian concept of purity to the modern concept of pure stoichiometric compounds. The history of the concept of ??pure substances?? shows that modern chemists?? concept of purity abstracted from usefulness rather than being opposed to it. Thus modern chemists?? interest in pure chemical substances does not presuppose a concept of pure science.  相似文献   

20.
To gain a complete understanding of a chemical reaction, it is necessary to determine the structural changes that occur to the reacting molecules during the reaction. Chemists have long dreamed of being able to determine the molecular structure changes that occur during a chemical reaction, including the structures of transition states (TSs). The use of ultrafast spectroscopy to gain a detailed knowledge of chemical reactions (including their TSs) promises to be a revolutionary way to increase reaction efficiencies and enhance the reaction products, which is difficult to do using conventional methods that are based on trial and error. To confirm the molecular structures of TSs predicted by theoretical analysis, chemists have long desired to directly observe the TSs of chemical reactions. Direct observations have been realized by ultrafast spectroscopy using ultrashort laser pulses. Our group has been able to stably generate visible to near‐infrared sub‐5‐fs laser pulses using a noncollinear optical parametric amplifier (NOPA). We used these sub‐5‐fs pulses to study reaction processes (including their TSs) by detecting structural changes. We determine reaction mechanisms by observing the TSs in a chemical reaction and by performing density‐functional theory calculations. DOI 10.1002/tcr.201000018  相似文献   

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