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Showing papers in "Russian Chemical Reviews in 2001"


Journal ArticleDOI
TL;DR: In this article, the properties of detonation synthesis ultradispersed diamonds (UDD) are summarized and systematised for the first time, and the potential application fields of UDD are considered.
Abstract: Published data on the properties of a novel nanomaterial viz., detonation synthesis ultradispersed diamonds (UDD), are summarised and systematised for the first time. Certain properties of UDD synthesised under different conditions are compared. Particular attention is drawn to substantiation of the cluster model of UDD and the fractal nature of their aggregates. The potential application fields of UDD are considered. Operating parameters of new materials are presented. The bibliography includes 110 references.

414 citations


Journal ArticleDOI
TL;DR: In this paper, the reactivities of metallic nanosystems in catalytic processes are considered, due to their unique microstructures, electronic properties and high specific surfaces of the active centres.
Abstract: The reactivities of metallic nanosystems in catalytic processes are considered. The activities of nanoparticles in catalysis are due to their unique microstructures, electronic properties and high specific surfaces of the active centres. The problems of increasing the selectivities of catalytic processes are discussed using several nanosystems as examples. The mutual effects of components of bimetallic nanoparticles are discussed. The prospects for theoretical and experimental investigations into catalytic nanosystems and the construction of industrial catalysts based on them are evaluated. The bibliography includes 207 references.

185 citations


Journal ArticleDOI
TL;DR: In this article, the main chemical and physicochemical properties and the methods of modification of carbon nanotubes, a novel promising material, are discussed and the feasible and potential fields of applications of carbon Nanotubes are outlined.
Abstract: The review concerns the main chemical and physicochemical properties and the methods of modification of carbon nanotubes, a novel promising material. The feasible and potential fields of applications of carbon nanotubes are outlined. The bibliography includes 573 references.

122 citations


Journal ArticleDOI
TL;DR: The structure, taxonomic distribution and biological activities of polar steroids isolated from various marine organisms over the last 8-10 years are considered in this paper, where the peculiarities of steroid biogenesis in the marine biota and their possible biological functions are discussed.
Abstract: Structures, taxonomic distribution and biological activities of polar steroids isolated from various marine organisms over the last 8—10 years are considered. The peculiarities of steroid biogenesis in the marine biota and their possible biological functions are discussed. Syntheses of some highly active marine polar steroids are described. The bibliography includes 254 references.

119 citations


Journal ArticleDOI
TL;DR: In this paper, the size effects in single component and multicomponent solid-phase systems are discussed, and the results of studies of the properties of nanocomposites and nanoparticles are discussed.
Abstract: Size effects in single-component and multicomponent solid-phase systems are discussed. Peculiarities of the size effects in microcrystalline and nanoscale systems are analysed. Methods for mechanochemical synthesis of nanoparticles are considered. Chemical properties of nanoscale systems are analysed. Particular attention is paid to the results of studies of the properties of nanocomposites and nanoparticles. Problems concerning their stability and the possibility of mechanochemical synthesis of these systems are discussed. The bibliography includes 175 references.

111 citations


Journal ArticleDOI
TL;DR: In this paper, a classification of nanoclusters and nanosystems based on the method of their preparation is proposed, and the appearance of new properties upon combination of nan-clusters into a nan-osystem is noted.
Abstract: Data on the structures and properties of nanoclusters and nanocluster systems are analysed. A classification of nanoclusters and nanosystems based on the method of their preparation is proposed. Methods for assembling nanoclusters to give nanostructures, the main principles of assembling and the types of nanosystems are described. The appearance of new properties upon combination of nanoclusters into a nanosystem is noted. The bibliography includes 274 references.

106 citations


Journal ArticleDOI
TL;DR: In this article, the structure, synthesis, stability and reactivity of sulfur-containing reducing agents with C-S or S-S bonds are surveyed and the applications of these compounds in the studies of nonlinear phenomena in chemical kinetics and in guanidine syntheses are considered.
Abstract: Data on the structure, synthesis, stability and reactivity of sulfur-containing reducing agents with C–S or S–S bonds — sodium dithionite, sodium hydroxymethanesulfinate and thiourea oxides — are surveyed. Reactions of anaerobic and aerobic decomposition of sulfur-containing reducing agents are discussed. The applications of these compounds in the studies of non-linear phenomena in chemical kinetics and in guanidine syntheses are considered. The bibliography includes 165 references.

75 citations


Journal ArticleDOI
TL;DR: In this article, the most important rearrangements of sulfoxides and sulfones to stereoselective total syntheses of natural compounds are systematised and a bibliography includes 175 references.
Abstract: Data on applications of the most important rearrangements of sulfoxides and sulfones to stereoselective total syntheses of natural compounds are systematised. The bibliography includes 175 references.

70 citations


Journal ArticleDOI
TL;DR: In this paper, the effect of N2O on the environment and the possibility of its utilisation are considered, focusing on the processes in which the oxidising potential of nitrous oxide can be employed.
Abstract: Modern trends of the chemistry of nitrous oxide are discussed. Data on its structure, physical properties and reactivity are generalised. The effect of N2O on the environment and the possibility of its utilisation are considered. Attention is focused on the processes in which the oxidising potential of nitrous oxide can be employed. The bibliography includes 329 references.

69 citations


Journal ArticleDOI
TL;DR: In this paper, the use of silica gel in organic synthesis is discussed and some specific features of cyclisation reactions, rearrangements, reduction, oxidation, condensation, formylation, hydration and dehydration, protection of functional groups, etc., are discussed.
Abstract: The data on the use of silica gel in organic synthesis are presented. Some specific features of cyclisation (both intra- and intermolecular) reactions, rearrangements, reduction, oxidation, condensation, formylation, hydration and dehydration, protection of functional groups, etc., in the presence of silica gel, are discussed. The bibliography includes 96 references.

68 citations


Journal ArticleDOI
TL;DR: In this article, the authors surveyed and described data on organic chemosensors published over recent years and provided 165 references, including 165 references from a bibliography of 165 references.
Abstract: Data on organic chemosensors published over recent years are surveyed and described systematically. The bibliography includes 165 references.

Journal ArticleDOI
TL;DR: In this article, the results of studies on the nanochemistry of metals published in recent years are generalised and primary attention is centred on the methods for the synthesis of nanoparticles and their chemical reactions.
Abstract: The results of studies on the nanochemistry of metals published in recent years are generalised. Primary attention is centred on the methods for the synthesis of nanoparticles and their chemical reactions. The means of stabilisation of nanoparticles which involve individual metals and incorporate atoms of several metals are considered as well as their physicochemical properties. Self-assembling processes of nanoparticles are described. The prospects of using metal nanoparticles in semiconductor devices, catalysis, biology and medicine are discussed. The bibliography includes 165 references.

Journal ArticleDOI
TL;DR: In addition to the conventional (step-by-step) methodology which consists of polymerisation of monomers in the presence of macrocycles, molecular self-assembly is gaining an ever increasing significance as discussed by the authors.
Abstract: Various approaches to the synthesis of rotaxanes and polyrotaxanes are considered. The principles employed in the design of highly organised structures comprising rod-shaped polymeric molecules, viz., macromolecular inclusion complexes, are discussed. In addition to the conventional (step-by-step) methodology which consists of polymerisation of monomers in the presence of macrocycles, molecular self-assembly is gaining an ever increasing significance. The main emphasis is laid on the preparation and characterisation of inclusion complexes which are based on cyclodextrins and linear synthetic polymers. The bibliography includes 138 references.

Journal ArticleDOI
TL;DR: In this paper, the use of 1,3-dipolar cycloaddition reactions of nitrile oxides in the synthesis of natural compounds and their analogues is systematised and reviewed.
Abstract: The published data on the use of 1,3-dipolar cycloaddition reactions of nitrile oxides in the synthesis of natural compounds and their analogues are systematised and reviewed. The bibliography includes 145 references.

Journal ArticleDOI
TL;DR: The potential of the chromaticity method is demonstrated and the prospects of its further development are discussed in this paper, where the biblioraphy includes 196 references and the potential of its method is discussed.
Abstract: Data on the application of the chromaticity method in chemical analysis and in various branches of industry are surveyed. The potential of the method is demonstrated and the prospects of its further development are discussed. The biblioraphy includes 196 references.

Journal ArticleDOI
TL;DR: In this paper, the influence of stable radicals, iniferters, organoelement compounds and other active additives on the reactivity of macroradicals and the elementary steps of the (co)polymerisation of acrylic and some other monomers are generalised.
Abstract: Data on the influence of stable radicals, iniferters, organoelement compounds and other active additives on the reactivity of macroradicals and the elementary steps of the (co)polymerisation of acrylic and some other monomers are generalised. New approaches to the control of the lifetime of the polymer chain and of the chain propagation stage are analysed. The problems of synthesis of compositionally homogeneous homo- and copolymers by radical polymerisation are considered. The bibliography includes 247 references.

Journal ArticleDOI
TL;DR: In this paper, the results of determination of the rate constants for nonradiative transitions between higher excited singlet and triplet states using different methods are summarised and interpreted in terms of the exchange-resonance theory of NRT.
Abstract: Ultrafast nonradiative transitions between electronic levels of aromatic and dye molecules, competing with fast photochemical reactions (e.g., electron or proton transfer, photoisomerisation, etc.), are considered. The results of determination of the rate constants for nonradiative transitions between higher excited singlet and triplet states using different methods are summarised. The experimental data are interpreted in terms of the exchange-resonance theory of nonradiative transitions. The bibliography includes 189 references.

Journal ArticleDOI
TL;DR: In this paper, the development of the main concepts of electrochemistry initiated by the stream of nanoscopic information is considered, and the prospects for local studies of processes on charged interfaces, elementary steps of these processes and application of nanoelectrodes and related systems in interdisciplinary fields are discussed.
Abstract: General characteristics of size-dependent phenomena in electrochemical systems are given. Primary attention is paid to methodical achievements of nanoelectrochemistry, which is a line of research created over the last 15 years. The development of the main concepts of electrochemistry initiated by the stream of nanoscopic information is considered. The prospects for local studies of processes on charged interfaces, elementary steps of these processes and application of nanoelectrodes and related systems in interdisciplinary fields are discussed. The bibliography includes 198 references.

Journal ArticleDOI
TL;DR: In this paper, the main factors that influence the concentration limits of existence of non-equilibrium solid solutions prepared by the mechanochemical method are revealed, and it is demonstrated that the formation of solid solutions may involve several stages.
Abstract: The current state of studies on the mechanochemical synthesis of binary metallic systems is considered. It is shown that this method is suitable for the preparation of intermetallic compounds and solid solutions in concentration limits of equilibrium diagrams of many binary systems. The mechanochemical approach is demonstrated to exhibit the most promise for preparing intermetallic compounds in systems characterised by large differences in the melting points and in the densities of the initial components as well as phases with nanometer grain sizes and metastable phases. The major factors, which influence the concentration limits of existence of non-equilibrium solid solutions prepared by the mechanochemical method, are revealed. Using numerous examples, it is demonstrated that the formation of solid solutions may involve several stages. At the first stage, nanosized layered composite structures are formed with simultaneous dispersion of the initial components (the formation of a large contact area). The second stage involves the synthesis of intermetallic compounds in nanosized layered composites. At the third step, the intermetallic compounds are dissolved in a metal solvent to give a solid solution. The bibliography includes 397 references.

Journal ArticleDOI
TL;DR: In this paper, the structure and reactivities of nitrosonium complexes of organic compounds are discussed. But the main focus is on the electronic structure of the NO+ cation, which is responsible for a wide structural variety of NO+ complexes.
Abstract: Data on the structures and reactivities of nitrosonium complexes of organic compounds are systematised and generalised. The characteristic features of the electronic structure of the NO+ cation are responsible for a wide structural variety of nitrosonium complexes. Reactions of nitrosonium complexes are described. The bibliography includes 172 references.

Journal ArticleDOI
TL;DR: The published data on the synthesis and chemical transformations of xenon derivatives are generalised and analyzed in this paper, with a bibliography of 489 references and references from the authors.
Abstract: The published data on the synthesis and chemical transformations of xenon derivatives are generalised and analysed. The bibliography includes 489 references.

Journal ArticleDOI
TL;DR: The data of IR, 1H NMR and electronic absorption spectroscopy of porphyrins and their precursors and derivatives are analyzed, systematised and generalised as discussed by the authors.
Abstract: The data of IR, 1H NMR and electronic absorption spectroscopy of porphyrins and their precursors and derivatives are analysed, systematised and generalised The bibliography includes 105 references

Journal ArticleDOI
TL;DR: In this paper, the relationship between the parameters affecting the reaction kinetics, viz., mixing time, duration of a chemical reaction and the residence time of the system in the extruder reactor, and the structure of the materials produced are analyzed.
Abstract: Chemical modification and blending of polymers in an extruder reactor are discussed. Relationships between the parameters affecting the reaction kinetics, viz., mixing time, duration of a chemical reaction and the residence time of the system in the extruder reactor, and the structure of the materials produced are analysed. The mechanisms of (i) grafting of low-molecular-mass compounds onto polymers; (ii) reactions between terminal groups of different polymers and (iii) transesterification and interchange reactions are considered. The factors affecting the mechanism of dynamic vulcanisation and the properties of thermoplastic elastomers are identified. Solid-phase reactions of polysaccharides in an extruder are discussed. The priority aspects of studies on the chemical modification and blending of polymers are noted. The bibliography includes 90 references.

Journal ArticleDOI
TL;DR: In this paper, a survey of the interaction of carbon nanomaterials (fullerenes, carbon nanotubes, graphite nanofibres and their metal-doped modifications) with hydrogen is presented.
Abstract: Data on the interaction of carbon nanomaterials (fullerenes, carbon nanotubes, graphite nanofibres and their metal-doped modifications) with hydrogen are surveyed. New results on the preparation and properties of hydrofullerenes are presented. The prospects for the use of carbon nanomaterials as reversible hydrogen sorbents are discussed. The bibliography includes 183 references.

Journal ArticleDOI
TL;DR: Methods of synthesis of (het)aroylpyruvic acids and their acyclic derivatives (esters, amides and hydrazides) and their reactions with various C-, N-, O-, S-nucleophiles are described in this article.
Abstract: Methods of synthesis of (het)aroylpyruvic acids and their acyclic derivatives (esters, amides and hydrazides), and their reactions with various C-, N-, O-, S-nucleophiles are described. Problems of tautomerism and biological activity of (het)aroylpyruvates and products of their transformation are briefly considered. The bibliography includes 191 references.

Journal ArticleDOI
TL;DR: In this article, the limits of structural distortions in carbon compounds and their unusual chemical properties are demonstrated using many examples of'record-breaking' molecules, the structural parameters of which (carbon-carbon bond lengths, bond and torsion angles) differ appreciably from the typical most frequently encountered values.
Abstract: Organic molecules, the structural parameters of which (carbon–carbon bond lengths, bond and torsion angles) differ appreciably from the typical most frequently encountered values, are discussed. Using many examples of 'record-breaking' molecules, the limits of structural distortions in carbon compounds and their unusual chemical properties are demonstrated. Particular attention is devoted to strained compounds not yet synthesised whose properties have been predicted using quantum-chemical calculations. Factors that ensure the stability of such compounds are outlined. The bibliography includes 358 references.

Journal ArticleDOI
TL;DR: In this article, the use of sulfonium ylides in the synthesis of carbocyclic and hetercyclic compounds is analyzed, systematised and generalised.
Abstract: Data on the use of sulfonium ylides in the synthesis of carbocyclic and heterocyclic compounds published over the last 15 years are analysed, systematised and generalised. The bibliography includes 139 references.

Journal ArticleDOI
TL;DR: In this article, the main mechanisms of the anion (fluoride ion) transport in fluoride and oxy-fluoride glasses are analyzed. And methods for optimisation of the conductivity characteristics of the glasses in question are considered.
Abstract: Main mechanisms of the anion (fluoride ion) transport in fluoride and oxyfluoride glasses are analysed. The variation in the transport number of F– ions depending on the glass composition is followed. Methods for optimisation of the conductivity characteristics of the glasses in question are considered. The prospects of using fluoride-conducting glasses in electrochemical devices are discussed. The bibliography includes 90 references.

Journal ArticleDOI
TL;DR: In this article, the main stages of the process are distinguished and characterised, focusing on elementary homogeneous reactions, deposition of silicon from the gas phase and formation of aerosols.
Abstract: Data on the mechanism of thermal decomposition of silanes are generalised. The main stages of the process are distinguished and characterised. Attention is concentrated on the elementary homogeneous reactions, deposition of silicon from the gas phase and formation of aerosols. Various models of formation of aerosols are considered. The results of theoretical and experimental investigations of this process are discussed. Data on the chemical composition of the solid product of silane pyrolysis (wall deposit and aerosol particles) are presented. It is noted that the hydrogen content in the solid product varies over wide limits. The bibliography includes 211 references.

Journal ArticleDOI
TL;DR: The application of synchrotron radiation in chemistry and materials science is discussed in this paper. But the main focus of this paper is on the use of combined methods of X-ray and electron spectroscopy.
Abstract: Modern modifications of the conventional X-ray methods of physicochemical analysis (X-ray and electron spectroscopy, diffraction methods, etc.) and new combined techniques using X-ray synchrotron radiation are considered. Unique characteristics of synchrotron radiation are noted, namely, continuous spectrum, exceptionally high intensity, polarisation, coherence, pulse nature, etc. The key trends in the use of combined methods in chemistry and materials science including studies of substances under extreme conditions, the study of rapid processes, studies with high spatial resolution are discussed. The achievements in the applications of synchrotron radiation are illustrated by examples from various fields of chemistry and related sciences. The bibliography includes 405 references.