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1.
我国目前中学化学实验研究述评   总被引:2,自引:0,他引:2  
通过报刊检索法,以3种中等化学教育核心期刊为研究对象,分析出目前我国中学化学实验研究主要分为3种类型:理论研究;经验总结或理论运用;具体实验设计。同时分析出:我国中学化学实验研究设计角度较为全面,但方法水平总体不高,对新课程下的实验设计研究不够。解决的途径为:加强实验设计的理论研究;更新广大一线教师的教育理念;提升中学化学教师实验设计水平。  相似文献   

2.
There is currently great interest in pharmaceutical proteins, and work in this area, from basic research to drug marketing, is expanding vigorously. The starting points of these developments are genetic engineering and biotechnology, which contribute to the discovery of new proteins and allow them to be produced on a worthwhile scale. Ever since the commercial introduction of insulin in 1923, of thyroid hormone in 1934, of factor VIII in 1948, and of calcitonin in 1970, hormones, serum proteins, and enzymes have been firmly established as therapeutic agents. Immunomodulators and various tissue proteins are in a turbulent phase of development as a new approach to the therapy of tumors. Increasingly, diagnostic aids now take the form of enzymes and monoclonal antibodies, and recently there has even been development of vaccines based on defined single proteins and oligopeptides. Of the more than 200 pharmaceutical proteins which have been investigated to date, more than half are undergoing research and development, about 100 are in clinical trials, and a dozen or so have already been marketed. The most important indications for them are cardiovascular disorders, tumors, autoimmune diseases, and infections. Genetically engineered proteins can be used as active substances, which are chemically and biologically exactly defined, for new drug products and in research to acquire new information on therapeutic use, based on the concept of therapy with endogenous proteins. Very recent developments have shown that proteins, either in their natural form or modified, are becoming of increasing importance for research into active substances.  相似文献   

3.
刘莉  韩军  颜朝国  王玉良 《有机化学》2007,27(8):907-917
硫代杯芳烃是一类以硫原子取代桥联亚甲基的新型杯芳烃, 作为新一代超分子砌块, 在分子识别、超分子自组装、晶体工程和纳米材料等方面都获得了广泛的应用, 已成为当今超分子化学研究的新热点. 综述了硫代杯芳烃及其衍生物的合成、功能化修饰及应用方面的研究进展.  相似文献   

4.
Dissatisfaction with empirical methods, high expectations of the public, poorly harmonized international regulations, and rising costs have induced pharmaceutical research to search for new approaches. As a consequence, the medicinal chemist's professional activity is in a state of change. His synthetic strategy is being increasingly influenced by the reasoning of molecular biology. Novel classes of biologically active compounds demand the development of new synthetic methods beyond the scope of modern preparative organic chemistry: enzymes and microorganisms, cell cultures, and genetic engineering are harnessed to supply highly complex structures. Major efforts are devoted to the development of reliable structure-activity relationships to rationalize his work. Thus the field of medicinal chemistry stretches from physical and physical organic chemistry far into the realm of biosciences, and the interdisciplinary character of this research is rapidly increasing. The author endeavors to convey an impression of this complex subject with the aid of selected examples.  相似文献   

5.
Clinical chemistry and laboratory medicine can look back over more than 150 years of eventful history. The subject encompasses all the medicinal disciplines as well as the remaining natural sciences. Clinical chemistry demonstrates how new insights from basic research in biochemical, biological, analytical chemical, engineering, and information technology can be transferred into the daily routine of medicine to improve diagnosis, therapeutic monitoring, and prevention. This Review begins with a presentation of the development of clinical chemistry. Individual steps between the drawing of blood and interpretation of laboratory data are then illustrated; here not only are pitfalls described, but so are quality control systems. The introduction of new methods and trends into medicinal analysis is explored, along with opportunities and problems associated with personalized medicine.  相似文献   

6.
The use of naturally occurring materials in biomedicine has been increasingly attracting the researchers’ interest and, in this regard, gum tragacanth (GT) is recently showing great promise as a therapeutic substance in tissue engineering and regenerative medicine. As a polysaccharide, GT can be easily extracted from the stems and branches of various species of Astragalus. This anionic polymer is known to be a biodegradable, non-allergenic, non-toxic, and non-carcinogenic material. The stability against microbial, heat and acid degradation has made GT an attractive material not only in industrial settings (e.g., food packaging) but also in biomedical approaches (e.g., drug delivery). Over time, GT has been shown to be a useful reagent in the formation and stabilization of metal nanoparticles in the context of green chemistry. With the advent of tissue engineering, GT has also been utilized for the fabrication of three-dimensional (3D) scaffolds applied for both hard and soft tissue healing strategies. However, more research is needed for defining GT applicability in the future of biomedical engineering. On this object, the present review aims to provide a state-of-the-art overview of GT in biomedicine and tries to open new horizons in the field based on its inherent characteristics.  相似文献   

7.
糖苷酶作为一种重要的生物催化剂,在工业生物催化领域有着广阔的应用前景。但天然糖苷酶存在催化活性低、热稳定性和底物选择性差等缺点,严重限制了它在规模化生产中的推广应用。近年,有关糖苷酶催化机制与结构功能关系的研究备受关注,特别是计算机辅助酶设计在相关研究领域发挥着越来越重要的作用。本文综述了糖苷酶分子设计改造过程中应用的计算机辅助方法:包括同源比对、分子对接以及动力学模拟;系统阐述了这些计算方法在糖苷酶的结构与功能关系解析、酶催化分子机制、酶催化性能改造方面的应用现状。通过对上述方法的深入分析可以预见,计算机辅助方法将成为糖苷酶分子设计改造的重要手段,并且开发智能精准的计算分析方法将成为加快酶分子定向改造的新发展趋势。  相似文献   

8.
A decade of significant research has led to the emergence of photovoltaic solar cells based on perovskites that have achieved an exceptionally high-power conversion efficiency of 26.08%. A key breakthrough in perovskite solar cells (PSCs) occurred when solid hole-transporting materials (HTMs) replaced liquid electrolytes in dye-sensitized solar cells (DSSCs), because HTMs play a crucial role in improving photovoltaic performance as well as cell stability. This review is mainly focused on the HTMs that are responsible for hole transport and extraction in PSCs, which is one of the crucial components for efficient devices. Here, we have reviewed small molecular as well as polymeric HTMs that have been reported in the last two years and discussed their performance based on the analysis of their molecular architectures. Finally, we include a perspective on the molecular engineering of new functional HTMs for highly efficient stable PSCs.  相似文献   

9.
“The following remarks consist partially of matter of fact, and partially of opinion. The former will be permanent; the latter must vary with the detection of error, or the improvement of knowledge. I hazard them with diffidence, and hope they will be examined with candour.” These declarations, which stem from the famous book “An Account of the Foxglove and some of its Medical Uses” by physician William Withering in 1785 in which he introduced preparations from digitalis leaves in the therapy of dropsy (cardiac failure), are cited here by the senior author because of his awareness of the difficulties in presenting a balanced report on his life-long research project on the further development of digitalis. His decision to devote himself to digitalis research originated at the bedside, when as a physician he experienced the grim final stages of cardiac failure in which no real help for the patients is possible. Unfortunately, his research project did not fit into the research program decreed by the Ministry of Science of the German Democratic Republic, so that he was ordered to stop the digitalis project in favor of biomembrane studies. Fortunately, he got round the ban simply by labeling the digitalis-like acting steroids as probes for the cell membrane-located Na+/K+-transporting ATPase which he had just recognized as the digitalis target (receptor) enzyme. These and other ventures by the authors are collated here for the first time. The aim of this review is to foster straightforward research for solving a major challenge: the development of steroidal drugs for the prevention and cure of cardiac failure.  相似文献   

10.
A new type of ligand, which is able to form axially chiral, supramolecular complexes was designed using DFT calculations. Two chiral monomers, each featuring a covalently bound chiral auxiliary, form a bidentate phosphine ligand with a twisted, hydrogen‐bonded backbone upon coordination to a transition metal center which results in two diastereomeric, tropos complexes. The ratio of the diastereomers in solution is very temperature‐ and solvent‐dependent. Rhodium and platinum complexes were analyzed through a combination of NMR studies, ESI‐MS measurements, as well as UV‐VIS and circular dichroism spectroscopy. The chiral self‐organized ligands were evaluated in the rhodium‐catalyzed asymmetric hydrogenation of α‐dehydrogenated amino acids and resulted in good conversion and high enantioselectivity. This research opens the way for new ligand designs based on stereocontrol of supramolecular assemblies through stereodirecting chiral centers.  相似文献   

11.
We outline a methodology for efficiently computing the electromagnetic response of molecular ensembles. The methodology is based on the link that we establish between quantum-chemical simulations and the transfer matrix (T-matrix) approach, a common tool in physics and engineering. We exemplify and analyze the accuracy of the methodology by using the time-dependent Hartree-Fock theory simulation data of a single chiral molecule to compute the T-matrix of a cross-like arrangement of four copies of the molecule, and then computing the circular dichroism of the cross. The results are in very good agreement with full quantum-mechanical calculations on the cross. Importantly, the choice of computing circular dichroism is arbitrary: Any kind of electromagnetic response of an object can be computed from its T-matrix. We also show, by means of another example, how the methodology can be used to predict experimental measurements on a molecular material of macroscopic dimensions. This is possible because, once the T-matrices of the individual components of an ensemble are known, the electromagnetic response of the ensemble can be efficiently computed. This holds for arbitrary arrangements of a large number of molecules, as well as for periodic or aperiodic molecular arrays. We identify areas of research for further improving the accuracy of the method, as well as new fundamental and technological research avenues based on the use of the T-matrices of molecules and molecular ensembles for quantifying their degrees of symmetry breaking. We provide T-matrix-based formulas for computing traditional chiro-optical properties like (oriented) circular dichroism, and also for quantifying electromagnetic duality and electromagnetic chirality. The formulas are valid for light-matter interactions of arbitrarily-high multipolar orders.  相似文献   

12.
Based on the situation of China University of Petroleum (East China) and the students' training characteristics, we have explored the reasonable teaching design on the basis of combining the theory and features of physical chemistry course with the practices, to facilitate chemical knowledge acquisition in non-chemical engineering majors. Teaching reforms such as using a variety of teaching methods and evaluation modes were employed in oil & gas storage and transportation engineering major, which has received significant teaching results.  相似文献   

13.
The formation of supramolecular structural units through self-assembly is a powerful method to design new architectures and materials endowed with specific properties. With the aim of adding a group of versatile tectons to the toolkit of crystal engineers, we have devised and synthesised four new V-shaped building blocks characterised by an aryl acetylene scaffold comprising three substituted pyridine rings connected by two triple bonds. The judicious choice of different substituents on the pyridine rings provides these tectons with distinctive steric, electrostatic and self-assembly properties, which influence their crystal structures and their ability to form co-crystals. Co-crystals of the tectons with tetraiododifluorobenzene were obtained both via traditional and mechanochemical crystallisation strategies, proving their potential use in crystal engineering. The energetic contributions of the supramolecular interactions at play in the crystal lattice have also been evaluated to better understand their nature and strength and to rationalise their role in designing molecular crystals.  相似文献   

14.
Rational and generalisable methods for engineering surface functionality will be crucial to realising the technological potential of nanomaterials. Nanoparticle‐bound dynamic covalent exchange combines the error‐correcting and environment‐responsive features of equilibrium processes with the stability, structural precision, and vast diversity of covalent chemistry, defining a new and powerful approach for manipulating structure, function and properties at nanomaterial surfaces. Dynamic covalent nanoparticle (DCNP) building blocks thus present a whole host of possibilities for constructing adaptive systems, devices and materials that incorporate both nanoscale and molecular functional components. At the same time, DCNPs have the potential to reveal fundamental insights regarding dynamic and complex chemical systems confined to nanoscale interfaces.  相似文献   

15.
中烟工业公司为云南烟草“十一五”时期烟草工业科技的发展做出了指导方针,数字烟草作为实施云南烟草品牌差异化发展的六个重点领域之一,有极大的发展空间。烟草的数字性不能仅仅停留在企业的IT设备上,应该成为一种企业思维,形成企业的一种大局面观,这是数字烟草内涵的表现。烟  相似文献   

16.
Which compound classes are best suited as probes and tools for chemical biology research and as inspiration for medicinal chemistry programs? Chemical space is enormously large and cannot be exploited conclusively by means of synthesis efforts. Methods are required that allow one to identify and map the biologically relevant subspaces of vast chemical space, and serve as hypothesis‐generating tools for inspiring synthesis programs. Biology‐oriented synthesis builds on structural conservatism in the evolution of proteins and natural products. It employs a hierarchical classification of bioactive compounds according to structural relationships and type of bioactivity, and selects the scaffolds of bioactive molecule classes as starting points for the synthesis of compound collections with focused diversity. Navigation in chemical space is facilitated by Scaffold Hunter, an intuitively accessible and highly interactive software. Small molecules synthesized according to BIOS are enriched in bioactivity. They facilitate the analysis of complex biological phenomena by means of acute perturbation and may serve as novel starting points to inspire drug discovery programs.  相似文献   

17.
Surface functionalization of carbon materials is of interest in many research fields, such as electrocatalysis, interfacial engineering, and supercapacitors. As an emerging carbon material, γ-graphyne has attracted broad attention. Herein, we report that the surface functionalization of a γ-graphyne-like carbon material ( γ-G1 ) is achieved by immobilizing functional groups via the click chemistry. Texture analysis of aberration-corrected microscopy, X-ray photoelectron spectroscopy, and electrochemistry confirm the successful surface modification of γ-G1 through a strong covalent linkage 1,2,3-triazole. The direct linkage of functional groups on γ-G1 via the click chemistry represents a general method for preparing other functional materials by using γ-graphyne-like materials as a skeleton.  相似文献   

18.
The structural characterization of materials and the tailoring of their properties is an important area of chemical research. A new trend in this area is the recourse to lasers both for analytical as well as preparative purposes, exploiting the fact that lasers, by virtue of their properties (sharp energy, spatial and temporal resolution etc.), offer the most precise and selective interaction of energy and matter that we know. Furthermore, photochemical syntheses and material transformations can proceed “cold” and without causing damage to surface structures. Laser chemistry finds application in thin film deposition, in the formation of surface layers, as well as in (structuring) ablation or etching, and in the initiation and enforcing of reactions at surfaces. In the present paper an introduction to these new possibilities on the general basis of molecule-surface interactions is followed by a brief characterization of lasers suitable for such purposes. Thereafter, four examples are discussed: gas phase deposition from volatile organometallic compounds with photoelectric activation at the surface or photochemical activation of the gaseous species (e.g. by employing molecular beams). In this way (noble) metal contacts can be deposited on various substrates. Instead of surface deposition, nucleation can occur in the gaseous medium, yielding highly disperse powders, e.g. of silicon carbide. Finally, an etching reaction is discussed where the laser does not act as an energy source but as an analytical instrument to provide diagnostic and mechanistic information.  相似文献   

19.
Owing to the rapid development of new technologies, new forms of business, new industries and the major national development strategies of "Maritime power strategy", the applied chemistry specialty of Qingdao University is reformed and upgraded according to emerging engineering education (3E) project and featured with "marine chemical industry and medicine". In this paper, combined with the revision of the professional training program, the specialty of applied chemistry has increased the characteristic courses and course module of marine resources chemistry. Meanwhile, the course content is reformed, and the characteristic talent training is emphasized, which is of guiding significance for reforming and upgrading the traditional majors with 3E concepts.  相似文献   

20.
The education characters of emerging engineering education (3E) is summarized. The necessary for reform and construction of new chemistry-related majors based on the ideal of 3E is discussed. The main ideas and ways proposed and the main research progresses made by the Instructional Committee of Chemistry Majors, Mistry of Education are briefly introduced with emphasis on the setup of two new majors namely "Chemistry Metrology and Technology" and "Intelligent Molecular Engineering" and reform of "Energy Chemistry". It is of guidance significance for the future reform of chemistry-related majors based on the 3E idea.  相似文献   

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