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1.
袁进  郝京诚 《大学化学》2022,37(1):125-132
截止2020年诺贝尔化学奖共颁发了112次,其见证了化学学科的发展历程、化学学科与人类生活密不可分的联系,以及化学学科发展的最前沿。以诺贝尔化学奖为主线,联系诺贝尔化学奖趣闻,讲解化学学科将是人类生存的基础,乃至对人类社会和生存发展做出的重要贡献,可以使大家认识到化学学科的重要性,并且更加了解如何进行化学研究,促进化学学科的长足发展。  相似文献   

2.
元素周期表的发表是化学知识领域的里程碑,其在化学,尤其是无机化学的学习和研究中的贯穿指导作用和重要性为大家所共识。本文讨论了元素周期表在大学无机化学中的教育作用和开展方式,提出周期表的应用要将化学史与化学教育有机结合。在此基础上,展望周期表未来的发展。  相似文献   

3.
We have obtained the Bloch spin wave dispersion formula using the methods of spin-free quantum chemistry. The spin-free eigenvectors are waves in spin-free space. This development makes the point that Bloch spin waves are dynamically spin-free. The neutron diffraction transition moment for spin waves is calculated employing the antisymmetrized projections of vector products of spin-free eigenkets and spin kets and is found to be agreement with results of Moorhouse.  相似文献   

4.
The hydrophobic surface properties of structured poly-(p-xylylene) (PPX) films, as measured by water wettability, are studied as functions of surface chemistry, film composition, and surface roughness. We demonstrate the fabrication of very hydrophobic surfaces and control over adhesion properties via nanoscale modulation of roughness, changes in composition, and alteration of the surface chemistry of PPX films. The formation of superhydrophobic surfaces through the chemisorption of fluoroalkylsiloxane coatings to hydroxyl sites created on the nanostructured PPX surface is also illustrated. The ability to control both hydrophobicity and adhesion using nanostructured PPX films is a promising development because it may lead to a new generation of coatings with applicability ranging from self-cleaning surfaces to robotics.  相似文献   

5.
This Perspective presents a review and survey of the science and philosophy of my research career over the past five decades at Columbia as a physical organic chemist and photochemist. I explore the role of paradigms, structure, and geometric thinking in my own cognitive and intellectual development. The Perspective describes my investigations of high energy content molecules in electronically excited states and the development of electronic spin and supramolecular photochemistry chemistry. Current research dealing with the nuclear spin chemistry of H(2) incarcerated in buckyballs is illustrated. In the second part of this Perspective, I recount a personal role of the philosophy and history of science and the scientific communities' use of paradigms in their every day research and intellectual activities. Examples are given of the crucial role of geometry and structure in the rapid development of organic chemistry and physical organic chemistry over the past century.  相似文献   

6.
Although extensive previous studies have shown that strained [1]ferrocenophanes predominantly undergo ring-opening chemistry at the bridging atom E-cyclopentadienyl (E-Cp) bond, recent reports have highlighted that reactivity at the Fe-Cp bond can also occur, especially on photoactivation. We provide an overview of recent results from our group and those of other researchers. In addition, the development of photocontrolled living polymerizations of sila[1]ferrocenophanes using Fe-Cp bond cleavage chemistry is described.  相似文献   

7.
8.
A critically important strategy for synthetic chemistry is the development of "domino" processes: those capable of concatenating multiple transformations into a single step. Such transformations not only provide an increase in synthetic efficiency, but also imply the development of a significant degree of mechanistic understanding. We report herein a new domino reaction, in which a chromium-manganese redox couple is employed both to catalytically reduce an o-hydroxy nitroarene and to oxidatively cyclize a subsequently formed imine. We find that the reaction is most effective for starting o-hydroxy nitroarenes with a strongly electron-withdrawing group at the para position.  相似文献   

9.
Understanding of oxidative processes such as solution-phase ozonolysis in multiwalled carbon nanotubes (MWNTs) is of fundamental importance in devising applications of these tubes as components in composite materials, as well as for development of cutting and filling protocols. We present here an evaluation of various spectroscopic tools to study the structure and composition of functionalized nanotubes. We demonstrate near-edge X-ray absorption fine structure (NEXAFS) spectroscopy as a particularly useful and effective technique for studying the surface chemistry of carbon nanotubes.  相似文献   

10.
综述了图形处理器(GPU)在计算化学中的应用和进展.首先简单介绍了GPU在科学计算中应用的发展,然后分别详细讲述了迄今几个使用GPU和CUDA(compute unified device architecture,显卡厂商Nvidia推出的计算平台)开发工具设计的量子化学计算和分子动力学(MD)模拟的算法和程序,尤其对目前唯一完全使用GPU技术开发的量子化学计算软件TeraChem做了完备的介绍,包括算法、实现的细节和程序目前的功能.此外,本文还对GPU在计算化学上将会发挥的作用做出了极为乐观的展望.  相似文献   

11.
This review, divided into three sections, describes the contribution of the chemists' community to the development and application of triple helix strategy by using artificial nucleic acids, particularly for the recognition of DNA sequences incorporating base pair inversions. Firstly, the development of nucleobases that recognise CG inversion is surveyed followed secondly by specific recognition of TA inverted base pair. Finally, we point out in the last section recent perspectives and applications, driven from knowledge in nucleic acids interactions, in the growing field of nanotechnology and supramolecular chemistry at the border area of physics, chemistry and molecular biology.  相似文献   

12.
烯烃是重要的大宗有机化工原料,广泛用于塑料、树脂、橡胶等高分子材料和基础有机化工产品和中间体的生产.同时,烯烃也是重要的精细化工原料和中间体,广泛用于染料、医药、香料、农用化学品、水性油墨和感光树脂等精细化工领域.长链烯烃通常是由小分子烯烃聚合制得,而小分子烯烃和苯乙烯的合成在学术界和工业界备受关注.在脱氢、裂解、脱水等诸多合成方法中,烷烃脱氢制烯烃是直接而中的路线,包括直接脱氢和氧化脱氢.小分子烷烃和乙苯催化脱氢制备对应的烯烃,尤其是乙苯制苯乙烯,目前工业上主要采用铁基催化剂催化直接脱氢工艺.积炭失活是该工艺面临的严峻挑战.工业上采用引入大量过热水蒸气的方法来解决这一难题,同时,还可以为脱氢反应提供热量.但是,这势必造成巨大的能耗和反应器容积效率的显著降低.氧化脱氢工艺是放热反应,并可有效抑制积炭,但又存在过氧化所致的低选择性的问题.直接脱氢和氧化脱氢各有利弊.目前,科学家和工业界都在扬长避短,开展两种脱氢工艺的新结构高性能催化剂的研究,并取得了长足进展.碳催化是近年来发展起来的一类重要的无机非金属固相催化剂,在光催化、电催化,以及热催化领域得到了广泛关注同时也是材料领域研究的前沿和热点.碳材料,尤其是纳米碳,在诸多反应中展示出了比常规金属催化剂更好的催化性能,且具有可持续的特征.因此,碳催化具有广阔的发展空间和巨大的应用前景.众所周知,固体催化剂的催化性能重要依赖于催化剂表面催化活性位的性质及其可及性.元素组成、化学状态及缺陷边角特征决定着活性位的性质,而形貌、尺寸、形状、纹理、表面结构等催化剂的微结构特征决定着固相催化剂活性位的可及性.因此,探索有效的方法和策略,来调节固相催化剂的微结构和表面化学性质,已成为催化学术研究的热点领域.碳材料的表界面和边角的官能团和结构缺陷是催化反应的活性位.对于烷烃脱氢反应,碳材料的表界面羰基和结构缺陷是催化剂的活性位,而杂原子掺杂可以调控活性位的电子结构.本文综述了烷烃脱氢用碳催化剂微结构和表面化学调控方法和效果的最新研究进展,并讨论了烷烃脱氢碳催化材料的微结构和表面化学性质调控的重要性和严峻挑战.通过碳材料合成中前驱体的优选、合成方法和策略的创新,以及通过后处理的方法,均可有效调控碳催化剂的微结构和表面化学性质,从而调控其烷烃脱氢催化性能.碳催化用于烷烃脱氢反应制烯烃,尤其是直接脱氢,前景看好.目前,研究的碳催化剂多为粉末状,用于固定床,存在流体阻力大、压力降高、操作困难的问题,并有可能阻塞床层,造成安全隐患;用于流化床,粉末碳易于团聚,催化剂过滤分离困难,流失严重.纳米碳基整体式催化剂可以是碳催化的未来发展方向.但是,目前才刚刚起步.碳基整体式催化剂活性单元本身可及活性位的性质及活性单元的分散性、抗脱落性和整体式催化剂的机械强度、导热性等诸多问题需要深入研究和探讨.总之,碳催化烷烃脱氢,尤其是无氧化剂、无水蒸气条件下的直接脱氢,是经济、节能、清洁、高效的烯烃生产方法,具有广阔的发展空间和美好前景.微结构和化学性质的调变是调控固相催化剂催化活性位性质和可接近性的重要方法,碳催化材料及整体式催化剂的碳基活性单元微结构和化学性质的调控是实现其催化性能调控的有效策略.  相似文献   

13.
A general surface chemistry strategy is described for the development of a new switchable material. The method modulates a surface-immobilized-molecules structure by using two orthogonal "click" reactions based on Huisgen cycloaddition and oxime chemistry, where the oxime linkage is redox active and switchable. We demonstrate this strategy by developing a noninvasive, biocompatible, in situ surface chemistry that is able to modulate the affinity of a cell-adhesive peptide to cell integrin receptors to study dynamic cell adhesion and cell migration in real time and as a new hide-and-reveal strategy for application in new types of smart biofouling biomaterials.  相似文献   

14.
Yilei WANG  Jun LI 《大学化学》2018,33(10):25-32
With the fast development of theoretical chemistry methodologies and computer hardware and software technologies, computational chemistry has become more and more imperative in chemical science. Accordingly, we have initiated "Computational Chemistry Experiments" course based on "Introductory Computational Chemistry" course developed in the Department of Chemistry, Tsinghua University since 2013, to provide basic training and computational chemistry practices for undergraduate students. The popular quantum chemistry software Gaussian is used as the major tool in the course. We focus on the exploratory feature of computational chemistry, creating initial structures and optimizing geometries, to provide fundamental training for students to comprehend the difference of traditional experimental chemistry and modern computational chemistry. Systematic research training is offered to develop the creative thinking capacity of students in using computational chemistry methods in chemistry education and research.  相似文献   

15.
Over one century after its discovery, pyrylium salt chemistry has been extensively applied in preparing light emitters, photocatalysts, and sensitizers. In most of these studies, pyrylium salts acted as versatile precursors for the preparation of small molecules (such as furan, pyridines, phosphines, pyridinium salts, thiopyryliums and betaine dyes) and poly(pyridinium salt)s. In recent decades, pyrylium salt chemistry has emerged as a powerful approach for constructing complex macrocycles and metallo-supramolecules. In this perspective, we attempt to summarize the representative efforts of synthesizing and self-assembling large, complex architectures using pyrylium salt chemistry. We believe that this perspective not only highlights the recent achievements in pyrylium salt chemistry, but also inspires us to revisit this chemistry to design and construct macrocycles and metallo-supramolecules with increasing complexity and desired function.

This perspective summarizes the representative efforts of synthesizing and self-assembling large, complex architectures using pyrylium salt chemistry.  相似文献   

16.
Green chemistry is also called environment harmless or environment friendly chemistry.Green chemistry requires to use new synthetic methods, engineering technologies and processes to eliminate or reduce by-products, wastes or products that harmful to human health, community safety,and ecology environment. Green chemistry pursues to control the usage of the harmful and toxic materials, reduce waste emission, avoid necessity to treat the wastes; Green Chemistry advocates wastes management from the beginning, improving the efficiency of atoms, optimizing the use of resources and energy, lowering the cost of production. Green Chemistry technologies are the ultimate path to the clean chemical production in the future.Insight Co. takes "hospital of enterprises" and "bank of technologies" as our characteristics in business, and deems the development and spread of green chemistry as our mission. We developed an unique business model which combines education, research and production. In the past 8 years,we had applied and obtained more than 30 patents and received more than ten national and provincial awards in technology progress.We had made great progress in the manufacturing of organophosphorus pesticides, especially the production of omethoate, methamidophos, paraquat and glycyrrhizinic phosphor, etc., which made a stable foundation for INSIGHT's development. We had also achieved great success in the high efficiency low toxic pesticides, such as imidacloprid, etofenprox, metalaxyl and in the new synthetic methods in various amino acids as well as in the pharmaceutical intermediates. The new method of preparation indigo using N-phenylglycinonitrile is an advanced process in the world in terms of the clean production technology for Ferro cyanide and HCN's transformation rate improvement. We solved the pollution problem of the old route. The newly developed substituted product for indigo using a clean production technology which greatly reduced the material consumption and environmental pollution. Insight has facilities producing nearly 20 photo-initiators and developed the new technique for light-curing lubricity, water-born resin, the technique for water-bon coating and their associated applications. The successfully developed technology of new high performance emulsion will promote the technology advancement in the coating industry and the wide spread of new coating in China.Insight has developed a series of new technologies, including a novel reactor technology - using a newly designed patented blade, has been characterized as high efficiency & energy saving reactor.The novel technology research and development are widely applied in INSIGHT's ten-year practice.We studied and confirmed the non-thermal catalyzing effect of microwaves, proposed a "weak microwave" theory, and a chemical reaction rate equation. We proposed that in the existence of microwave magnesium ions and phosphate, amino acid can be activated to form peptide which maybe the path of the origin of life.A 3000mt/a pilot plant in Chongqing using carbon monoxide and hydrogen to produce dimethyl ether in a single step has been built via collaboration with the Dept. of Chemical Engineering at Tsinghua University. The large scale, low cost production of dimethyl ether may possible through comprehensive technology improvement. This technology will take full advantage of current ammonia production facilities, and try to solve the global fuel shortage problem.  相似文献   

17.
凝胶色谱仪是高分子化学学科日常科研工作的必备仪器.随着高校高分子化学学科的迅猛发展,如何提高该仪器的开放使用和管理维护变得十分重要.总结了管理的经验及体会.  相似文献   

18.
唐睿康 《化学进展》2009,21(6):1080-1084
金松寿教授是著名的量子化学及化学动力学专家。年近九旬的他如今仍然锲而不舍地在学习、研究,把握化学研究的发展方向。他在催化集团结构适应性及无机化合物溶解度领域做了大量的工作,重要的成就是发现了选择性分子间力并用以阐释物性如溶解度、吸附、色谱中的反常现象,还可以解释溶媒对反应速度的影响。相似的选择力后来被外国科学家在超分子研究中得到证实和发展。他还推动了控制论化学的应用,对化学中的许多疑难繁琐的现象给出清晰满意的解释。  相似文献   

19.
充满生机和科学机遇的磷化学研究所   总被引:1,自引:0,他引:1  
贺红武 《有机化学》2003,23(2):155-161
简要地综述了第十五届国际磷化学会议的报告内容,介绍了目前磷化学的主要 研究领域,包括不对称合成、配合化学,生物碱化学,药物化学,农业化学等相关 领域的研究动态及新进展。  相似文献   

20.
The present article is a direct continuation of the previous part III of this series of articles, which have been devoted to cultivating a new interdisciplinary region between chemistry and mathematics. In the present part IV, we develop two sets of fundamental theoretical tools, using methods from the field of resolution of singularities and analytic curves. These two sets of tools are essential in structurally elucidating the assertion of the Fukui conjecture (concerning the additivity problems) and the crux of the functional asymptotic linearity theorem (functional ALT) that proves the conjecture in a broad context. This conjecture is a vital guideline for a future development of the repeat theory (RST)—the central unifying theory in the First and the Second Generation Fukui Project.  相似文献   

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