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化学生物学新前沿——化学蛋白质组学 总被引:7,自引:0,他引:7
随着包括人类在内的主要模式生物的基因组计划的完成,生命科学的研究重心转向蛋白质组的研究--在对应基因组的整体蛋白质水平上系统研究调控细胞生命活动的蛋白质.化学蛋白质组学是化学生物学在后基因组时代的最新发展:化学蛋白质组学利用化学小分子为工具和手段,以基于靶蛋白质功能的新战略探测体内蛋白质组,是新一代的功能蛋白质组学.本文综述了化学蛋白质组学的最新进展、有关技术及其在生物医学和药物研发等方面的应用,并对化学蛋白质组学的发展趋势和前景进行了讨论. 相似文献
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José L. Gázquez Marco Franco-Pérez Paul W. Ayers Alberto Vela 《International journal of quantum chemistry》2019,119(2):e25797
The chemical reactivity concepts of density functional theory are studied through a unified view in the temperature-dependent approach provided by the grand canonical ensemble. This procedure leads to a more general perspective that enriches our understanding of the behavior of the average energy and its derivatives with respect to the average number of electrons, provides alternative definitions for those quantities that are “ill defined” at zero temperature, and allows one to determine the relationships among reactivity concepts at any temperature. In particular, it has been found that at high temperatures the parabolic model for reactivity indicators may be justified through the electronic entropy term in the Helmholtz free energy, and that at nonzero temperatures there is an electronic heat capacity contribution to the average energy. In summary, the unified view of the temperature-dependent approach is an important complement to the zero-temperature formulation that clarifies fundamental issues therein. 相似文献
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Vida Vičkačkaite Rolandas Kazlauskas Petras Serapinas Mudis Šalkauskas 《Mikrochimica acta》1996,123(1-4):207-215
In Lithuania research and development in chemical analysis are concentrated in scientific institutes and universities. The main fields of interest focus on biosensors, electrochemical sensors, sampling techniques and methods, study of atomization processes in spectrochemical analysis and noise evaluation in analytical measurements. Some laboratories also take part in international environmental monitoring programmes. There are about 50 researchers at the Ph.D. level engaged in analytical chemistry and several hundred technicians specialized in the field of analytical control. About one hundred chemical laboratories are active in scientific institutes, universities and factories. Specialized laboratories of chemical analysis are at the disposal of Environmental Control and Health Protection Departments and forensic investigation organizations. So far no laboratories are accredited according to the ISO 9000 norms. Special courses on analytical chemistry are offered at a few schools of higher education in the country. Only at the Department of Analytical Chemistry of the University of Vilnius specialized programmes are available to postgraduate students working towards a Ph.D. to improve their skills in current techniques of analytical chemistry. Recently the Technical Committee TC-16 for Chemical Analysis was formed within the standardization system of Lithuania. Its main activities are centered on issues such as national terminology, certified reference materials (CRMs), analytical methods and analytical quality assurance. There are numerous problems related to national terminology, the preparation of special documents in the field of analytical control and the production of regional environmental CRMs. Problems, also arise in obtaining and using CRMs for analytical instrument calibration and validation. 相似文献
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以化学用语、化学计算的发展为例,论述了追求简便是化学学科发展的重要推动力。如果教师给予正确的引导,合理追求简便将成为学生创新的不竭动力。以化学教学中2个简化不当的例子说明,过度追求简便会束缚学生的思维,阻碍教学研究的发展与兴盛。 相似文献
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The idea of popularity/abundance of chemical compounds is widely used in non-target chemical analysis involving environmental studies. To have a clear quantitative basis for this idea, frequency distributions of chemical compounds over indicators of their popularity/abundance are obtained and discussed. Popularity indicators are the number of information sources, the number of chemical vendors, counts of data records, and other variables assessed from two large databases, namely ChemSpider and PubChem. Distributions are approximated by power functions, special cases of Zipf distributions, which are characteristic of the results of human/social activity. Relatively small group of the most popular compounds has been denoted, conventionally accounting for a few percent (several million) of compounds. These compounds are most often explored in scientific research and are practically used. Accordingly, popular compounds have been taken into account as first analyte candidates for identification in non-target analysis. 相似文献
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按照时间脉络将我国中学化学实验教学划分为4个主要阶段。第3个阶段是“拨乱反正”、快速发展期,伴随着“文革”结束和中国共产党十一届三中全会的召开,我国的教育事业迎来了发展的新时代。在这一历史时期,中学化学实验教学围绕国家的中心工作,育人功能不断拓展,教学质量不断提升,在教学实践中产生了一些新的教学理念和教学方法,教师素质不断提高,实验教学理论也得到了发展。 相似文献
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Victor A. Snyder 《Journal of mathematical chemistry》2006,40(2):119-134
The classical thermodynamic treatment of chemical equilibria in closed systems is founded on theoretical formulations by J.W. Gibbs and Th. De Donder. These two theories represent mathematically equivalent energy variation problems, related to each other through a mass variable transformation analogous to coordinate transformations in mechanics. Associated with the change in mass variables, chemical potentials of reactive substances are defined differently in the two theories, and are subject to different sets of constraints. Traditionally, the two sets of constraints have been merged into one, by assuming that the chemical potential represents the same variable in both theories, an assumption that is formally inconsistent with the difference in chemical potential definitions. Merging of constraints is still possible if chemical potentials remain invariant in value as a manifestation of symmetry under a Gibbs – De Donder mass transformation, but such symmetry has not been investigated. Here we demonstrate chemical potential invariance by reformulating De Donder’s theory using Lagrange multipliers, and combining the resulting constraints on chemical potentials with the classical Gibbs constraints, in a phase equilibration thought experiment. A new form of the Gibbs–Duhem (GD) relation is derived in the De Donder mass system. Comparing this relation to the classical GD equation in Gibbs’ component framework, subject to chemical potential invariance, directly yields the linear operator mapping the De Donder mass variables onto the set of Gibbs component masses. Results are illustrated for a simple ion exchange reaction, in the process solving the longstanding problem of determining solid exchanger activities in ion exchanging mixtures. It is pointed out that, even though the Gibbs and De Donder formulations are mathematically equivalent, the formal structure of De Donder’s theory allows a more explicit and systematic treatment of constraints, and also defines chemical masses in a form more naturally adapted to typical experimental measurements. 相似文献
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《Angewandte Chemie (International ed. in English)》2017,56(50):15818-15827
Selenocysteine, the selenium‐containing analogue of cysteine, is the twenty‐first proteinogenic amino acid. Since its discovery almost fifty years ago, it has been exploited in unnatural systems even more often than in natural systems. Selenocysteine chemistry has attracted the attention of many chemists in the field of chemical biology owing to its high reactivity and resulting potential for various applications such as chemical modification, chemical protein (semi)synthesis, and protein folding, to name a few. In this Minireview, we will focus on the chemistry of selenium and selenocysteine and their utility in protein chemistry. 相似文献
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无机化学计算中采取一题多解可开拓学生的思维,加深对化学基本原理的理解和掌握,有利于巩固和提高所学知识,并加以灵活运用,做到触类旁通。文章以无机化学教学中化学平衡、电极电势2类问题的计算给予说明。 相似文献
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阐述在化学分析中,由于增强了化学计量意识,满意地解决了粘胶基碳布质量问题,显示出化学计量在产品质量保证中的重要作用。 相似文献
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The electronic energy structure of MC, M6C, and M12C carbide systems and iron martensite in the absence of spin polarization was studied by the local coherent potential method using the cluster version of the MT approximation in terms of multiple scattering theory. The local partial density of the electronic states of atoms in crystals was calculated and their electronic structures were compared. The peculiarities of chemical bonding in crystals are discussed. 相似文献
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《Physics and Chemistry of Liquids》2012,50(6):671-682
Abstract The concentration-concentration fluctuations in the long wavelength limit S cc(0) and the Warren-Cowley short range order parameters (SRO) α1 have been calculated for the Zn-Au liquid alloy at 1173 K by applying the Quasi Chemical Approximation (QCA). The results of the calculations show that Zn-Au liquid alloy manifest hetero-coordination throughout its whole concentration range. There exist evidence for the presence of two complexes Zn4AU3 and Zn4Au6. The Zn4Au3 complex which manifests dominance in the thermodynamic properties of the liquid alloy yielded a minimum short range order value of about αmin 1 ≈ ?0.26 while Zn4Au6 has its minimum as αmin 1 ≈ ?0.34. Studies from the S cc(0) indicate that these complexes are weak and hence cannot encourage glass formation in the liquid alloy. 相似文献
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The structural and electronic characters of four types of hydroxyl group-substituted anthocyanidins (pelargonidin, cyanidin, delphinidin, and aurantinidin) were examined using quantum chemical calculations. For these cationic molecules, both the planar and non-planar structures in the electronic ground state were determined at the B3LYP/D95 level of theory. We revealed that the planar structure is slightly more stable than the non-planar structure for each molecule. For the optimized planar structures, single excitation-configuration interaction (SE-CI) based on the restricted Hartree-Fock (RHF) wave function was evaluated and the electronic character in the low-excited states was discussed in terms of the MO theory. Symmetry adapted cluster (SAC)/SAC-CI calculations were also carried out to estimate the excitation energies precisely. The results showed that hydroxylation of the phenyl group causes a change in the excitation energies without taking the solvent effects into account. The results are in agreement with spectral experiments and previous MO calculations. 相似文献
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Glycoproteins are produced by the post‐translational modification process of proteins and they play an important role in mediating various biological processes. Our understanding towards biochemical functions of individual glycoproteins has been seriously hampered due to the heterogeneous expression of carbohydrate parts in glycoproteins. Despite the advancement in recombinant expression and chromatographic techniques, the isolation of pure glycoforms remains nearly impossible. To obtain homogenous glycoproteins, tremendous efforts hves been spent in developing various ligation and glycosylation techniques. This minireview discusses selected methods for the preparation and ligation of glycopeptides. The importance of the development of new chemical synthesis method for glycoproteins has also been discussed, which would be one of the next directions in this field. 相似文献