等物质的量定律及其应用

本文指出了滴定计算中等物质的量规则的缺陷,并提出了等物质的量定律,将这个反映化学反应客观规律的定律定义为:在氧化还原反应体系中氧化剂与还原剂得与失电子的物质的量相等;在酸碱反应体系中酸与碱得与失质子的物质的量相等;在沉淀反应中阳离子与阴离子所具有电荷的物质的量相等;在络合滴定中金属离子与氨羧络合剂的物质的量相等。等物质的量定律可用下式表达:(i=k)∑(i=1)△n(1/z_Ai)Ai=(i=P)∑(i=1)△n(1/z_Bi)Bi。这个定律及其表达式能使复杂的滴定分析计算简单化、规范化。     

Stoichiography and present-day analytical chemistry of solid inorganic substances and materials

The article covers factors that determine fundamental difficulties of chemical phase analysis of a mixture of solid phases of inorganic compounds. Stoichiographic principles and methods, novel for analytical chemistry and leading to the efficient solution of the problems of phase analysis, are discussed. Conditions of the selective separation of mixtures of multiphase multielement solid compounds and principles of the new method, fan-like separation, ensuring the extraction of individual phases from unseparated mixtures, are considered. An idea of a complex method of solving analytical problems by stoichiography methods in proposed. The problem of the multiplicity of objects of analysis is discussed and general principles of the efficient solution of problems of the detection and identification of components of complex mixtures of unknown chemical composition are considered.     

Computer simulation of the structure formation and disruption processes in the solid-liquid disperse systems

Results of the computer simulation of solid-liquid disperse systems are reported. Main regularities of the formation and disruption of the internal structure of such systems are demonstrated under static and dynamic conditions (including the combination of shear and orthogonal vibrations). The effect of the character of the interaction of dispersed phase particles, as well as of a number of parameters concerning the type and intensity of external actions on the behavior of disperse systems is shown. The possibility of the regulation of the character of microstructure and rheological properties of disperse systems by the combination of shearing and orthogonal vibrations is illustrated.     

Interaction of carbamazepine and promethazine in rabbits

The interaction of carbamazepine and promethazine in rabbits has been investigated. The influence of this interaction on the processes of biotransformation in the liver was revealed. The drugs were administered as single oral doses (100 mg of each drug) as well as simultaneously with an interval of 15 min. The sequence of administration of the drugs was varied. The influence of promethazine on the pharmacokinetics of carbamazepine is expressed by: (a) strong suppression of carbamazepine's level in plasma and appearance of multiple peaks of carbamazepine; (b) suppression of biotransformation of carbamazepine into carbamazepine-10,11-epoxide at the initial stages and its increase in the intermediate stages. These data are explained by the active capture of carbamazepine by liver at its primary transferal through the liver and sufficient presystem elimination of carbamazepine in the presence of promethazine. The character of kinetic curves of promethazine varies substantially under the influence of carbamazepine. However, this change is not as strong as in case of carbamazepine. The concentration of promethazine in plasma varies slightly and multiple peaks are not observed. The rate of terminal elimination of promethazine varies and abrupt prolonged segments of elimination appear at the initial and terminal stages of the process in return. These data perhaps indicate the induction of biotransformation of promethazine in the presence of carbamazepine-an inductor of microsomal liver enzymes. The changes of kinetics of promethazine and carbamazepine by simultaneous administration as compared with their administration separately, as well as a comparative consideration of pharmacokinetics of promethazine and carbamazepine by simultaneous administration show the existence of competition in the elimination between these drugs and the periodic saturation of liver for their biotransformation.     

扭辫分析法对糠醛聚合反应机理的研究

中村仪郎等对经酸催化而得的糠醛树脂通过红外和紫外光谱进行了结构分析。     

Water-soluble polyelectrolyte complexes of pyridine-containing polyphenylene dendrimers

The sizes of soluble polyelectrolyte complexes formed through mixing of solutions of dimethyl sulfate-alkylated rigid pyridine-containing polyphenylene dendrimers of various generations with the solution of sodium polystyrenesulfonate are measured with the use of dynamic light scattering. Effects of the length of the polyanion chain of the dendrimer, the generation number of the dendrimer, and the charge ratio of polymer components on the sizes of the complexes are examined. The results of this study are in agreement with the theoretical analysis of interaction between the charged dendrimer and the polyelectrolyte of the opposite charge sign and suggest the spontaneous formation of nanosized particles of water-soluble complexes.     

Lipids of the oils of the fruit and leaves ofHoppopha? rhamnoides

The analysis of some lipids of four forms of the common sea buckthorn has shown that they all differ with respect to the composition of the fatty acids of the triacylglycerols of the leaves. One of the forms is characterized by an infringement of the specificity of the composition of the fatty acids in positions 2 of the triacylglycerols of the oils of the seeds and the leaves.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. V. L. Komarov Institute of Botany, Academy of Sciences of the Azerbaidzhan SSR, Baku. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 710–715, November–December, 1981.     

Virtual screening of organic molecule databases. Design of focused libraries of potential ligands of NMDA and AMPA receptors

A system of virtual screening of organic molecule databases is designed, which permits preprocessing of databases, molecular docking to a three-dimensional model of receptor, and post-processing of the results obtained. Using this screening system, it is possible to reproduce positions of the known ligands in the glutamate sites of the NMDA and AMPA receptors and in the glycine site of the NMDA receptor, to substantially enrich the database with potentially active compounds, and to distinguish between the agonistic and antagonistic character of the action of these compounds in the case of docking to the open and closed forms of the binding sites. Based on the results of screening of a database of low-molecular-weight organic compounds (total of 135,000 structures) using models of the open and closed forms of the glutamate and glycine sites of the NMDA receptor and of the glutamate site of the AMPA receptor, focused libraries of potential agonists and antagonists of these sites were designed.     

能量分辨质谱鉴别卤代4(3H)-喹唑啉酮异构体

应用能量分辨质谱分别研究了氯代4(3H)-喹唑啉酮异构体和氟代4(3H)-喹唑啉酮异构体的单体及异构体单体的混合物的能量质谱裂分曲线。结果表明,在碰撞能量0.8～1.5V的变化范围内,氯代4(3H)-喹唑啉酮异构体单体及混合物的碎片离子m/z 145与m/z 125的离子强度比值相对于碰撞能量的变化曲线,即裂分曲线与氯官能团的取代位置密切相关,而氟代4(3H)-喹唑啉酮异构体单体及混合物的碎片离子m/z 136与m/z 108的离子强度比值的裂分曲线则与氟官能团的取代位置密切相关,差异显著;据此可以成功鉴别卤代4(3H)-喹唑啉酮异构体的单体及混合物的构成。     

The application of microfine ionites for the improvement of the efficiency of sorption processes in drug production (Review)

Results of the application of microfine ionites of different classes for sorption methods in the production of versatile drugs are systemized. Kinetic and dynamic parameters of sorption isolation and chemical purification of drugs with participation of ion-exchanger of small graining are discussed; essential advantages of their application allowing intensification of ion-exchange technological processes of drugs production are determined. The review can be useful at elaboration of new sorption methods used for the production of the wide assortment of drugs and, first of all, antibiotics, enzymes, and vitamins.     

Synthesis of Multicomponent Oxide Low-Dimensional Systems on the Surface of Porous Silicon Dioxide Using the Molecular Layering Method

Reflecting the research in the field of the surface chemistry of solids over the last 25-30 years, the results related to the application of the molecular layering method for the synthesis of surface low-dimensional structures of complex composition are presented. The regularities of formation of multicomponent mono-, multilayers on the surface of solid-phase matrices are studied on examples of chemical interactions, by a preset program, of chlorides and oxychlorides of titanium, vanadium, phosphorus, chromium, zinc, and iron with hydroxy and secondary functional groups of porous silicon dioxide. On the basis of chemical-analytical and spectroscopic data, structural schemes of synthesized products are proposed and functional interactions in multicomponent monolayers on the surface are considered. The reactivity of the element chlorides and oxychlorides as a function of the chemical composition of surface functional groups of silica and on synthesis conditions is estimated. In view of the revealed regularities of formation of complex low-dimensional systems on silica surface, prospects of application of the resulting data are considered for elaboration of scientific foundations of the chemical nanotechnology of production of solid-phase materials of various functional use, based on the molecular layering method.     

碳原子价轨道电负性对化学键性能的影响

研究了同一类型化学键X―C的键能、键长和H―C键的酸性等性能与碳原子价轨道电负性的定量关系。结果表明,X―C键能随碳原子价轨道电负性增加而线性增大;H―C与C―C键的键长随碳原子价轨道电负性增加而线性减小;H―C的酸性随碳原子价轨道电负性增加而线性增大。因而,对结构类似的有机化合物,可以采用碳原子价轨道电负性对实验测定的化学键性能作图,判断其测定结果正确与否。     

The correlation matrix of the position of a polymer chain: Unexpected results for the Gaussian coil model

A correlation matrix of the positioning of the elements of a macromolecule is a measure of the diversity of the conformations of these molecules in a considered statistical ensemble. The structure of the correlation matrix of molecules is presented as a relief of the dependence of the correlation coefficients on the relative position of the units of a polymer chain along its contour. This relief is shown to be nonmonotonic; there are significant correlations of the position of far located chain links. When the chain length is more than several tens of units, the relief shape is practically identical in a continuous or discrete space of any dimension, homogeneous or affine-transformed. This invariance may be disrupted by the macrocharacteristic fractioning of the chain system and mixing of the chain set, may be constructed via different algorithms, or may be due to the interaction of the chains. The presence of considerable correlations among the conformations of independently constructed macromolecules should be taken into account during selection of the conformations.     

Carbon nanotubes, new material for purification of water-ethanol mixtures from isomers of propanol

The possibility of purification of water-ethanol mixtures from the unwanted admixtures of higher alcohol, in particular, of the isomeric propanols, with the help of carbon nanomaterial is discussed. Results of quantum-chemical calculations of n-propanol and isopropanol on the surface of the single-walled carbon nanotube of the “armchair” type are presented. Investigations are carried out within the frame of model of molecular cluster using semi-empirical quantum chemical MNDO method. The possibility of adsorption of molecules of propanol isomers on the outer surface of nanotubes of small diameter as well the absence of adsorption of ethanol molecules on them is shown. It indicates the possibility of selective sorption with carbon nanotubes. Main geometric, electronic, and energy characteristics of obtained adsorption complexes are evaluated. A conclusion is made on the possibility to use carbon nanotubes for superfine purification of water-ethanol mixtures from the unwanted admixtures of n- and isopropanol.     

几种萘酞菁硅配合物的光动力效应的研究

研究了7种轴向配位的萘酞菁硅配合物的激发态性质、产生单重态氧的能力及对几种氨基酸的光敏氧化能力.研究表明,对于相同浓度的不同配合物来说,随着轴向配位基团推电子能力的逐渐增强,激发三重态寿命降低,产生单重态氧的能力逐渐下降,而产生单重态氧的能力是光敏氧化氨基酸反应速率的决定因素,因此,其光敏氧化氨基酸的一级反应速率常数逐渐减小.     

Trialing of the topological types of phase diagrams for unary systems

The topological isomorphism of polyhedra with tervalent vertices and phase diagrams of unary systems allows us to reduce the problem of constructing the full set of topological types of diagrams with tailored parameters to the problem of generating labeled graphs. Each of them is the Schlegel projection of some polyhedron onto one of its faces. This work concerns the problem of listing possible topological types of phase diagrams of unary systems. A great variety of the types of these diagrams is demonstrated.     

Harnessing the Capabilities of Spray Granulation in the Food Industry for the Production of Functional Foods

The article is the literature review of a current state of production technologies of powdery foodstuff, concentrates and multicomponent mixes. The need of the food industry for qualitative methods of processing of raw materials of different physical and chemical structure is noted. The authors give the reasons about need and possibility of a choice of granulation as a method of data processing of products. Physical and chemical features of granulation methods of disperse environments of various aggregate states based on the studied regularities and works of other authors are considered. The authors made the assumption of the application prospects of the method of liquid dispersion on the surface of particles in a suspended state for a granulation of foodstuff and they offered the alternative option. The possibility to use whey as binding element is considered. At the end of article authors draw the conclusion about the prospects of use of a method of dispersion of liquid on the surface of particles in a suspended state for a granulation of foodstuff.     

多相催化研究中化学动力学的作用(英文)

The paper presents shortly some of the important elements of the theory and of the practical applications of the kinetics of heterogeneous catalytic reactions. Discussed are some of the most important concepts of the kinetics of complex heterogeneous catalytic reactions,methodology of building kinetic models and mathematical treatment of experimental data,influence of heat and mass transfer,types of laboratory reactors,kinetics and nanosized catalysts and others. Examples for use of the kinetic studies for the development and application of industrial catalysts and modeling of industrial reactors are presented.     

聚乙烯醇对丙烯酰胺聚合行为的影响

<正> 聚乙烯醇(PVA)在烯类单体自由基聚合反应中作为分散剂使用已有很长历史,对于PVA在不同催化体系中与烯类单体接枝聚合的研究报道也不少,其中有人报道PVA对过硫酸盐的分解具有促进作用,并可导致甲基丙烯酸甲酯在PVA大分子上接枝;也有人报道了PVA与过硫酸铵在水溶液中的相互作用,本文研究了在低浓度过     

On origin and evolution of carbonic anhydrase isozymes: A phylogenetic analysis from whole-enzyme to active site

Genetic evolution of carbonic anhydrase enzyme provides an interesting instance of functional similarity in spite of structural diversity of the members of a given family of enzymes. Phylogenetic analysis of α-, β- and γ-carbonic anhydrase was carried out to determine the evolutionary relationships among various members of the family with the enzyme marking its presence in a wide range of cellular and chromosomal locations. The presence of more than one class of enzymes in a particular organism was revealed by phylogenetic time tree. The evolutionary relationships among the members of animal, plant and microbial kingdom were developed. The study revises a long-established notion of kingdom-specificity of the different classes of carbonic anhydrases and provides a new version of the presence of multiple classes of carbonic anhydrases in a single organism and the presence of a given class of carbonic anhydrase across different kingdoms.