Showing papers in "Russian Chemical Reviews in 2015"
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TL;DR: The state-of-the-art in the field of cathode and anode nanomaterials for lithium-ion batteries is considered in this article, where the authors focus on double phosphates and silicates of lithium and transition metals and also on vanadium oxides.
Abstract: The state-of-the-art in the field of cathode and anode nanomaterials for lithium-ion batteries is considered. The use of these nanomaterials provides higher charge and discharge rates, reduces the adverse effect of degradation processes caused by volume variations in electrode materials upon lithium intercalation and deintercalation and enhances the power and working capacity of lithium-ion batteries. In discussing the cathode materials, attention is focused on double phosphates and silicates of lithium and transition metals and also on vanadium oxides. The anode materials based on nanodispersions of carbon, silicon, certain metals, oxides and on nanocomposites are also described. The bibliography includes 714 references.
88 citations
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TL;DR: In this paper, the physicochemical properties of ionic liquids (heat capacity, thermal conductivity, thermal and radiation stability, viscosity, density, saturated vapour pressure and corrosion activity) are compared with the properties of some commercial heat transfer fluids.
Abstract: The practical aspects and prospects of application of ionic liquids as heat transfer fluids are discussed. The physicochemical properties of ionic liquids (heat capacity, thermal conductivity, thermal and radiation stability, viscosity, density, saturated vapour pressure and corrosion activity) are compared with the properties of some commercial heat transfer fluids. The issues of toxicity of ionic liquids are considered. Much attention is paid to known organosilicon heat transfer fluids, which are considered to have much in common with ionic liquids in the set of properties and are used in the review as reference materials. The bibliography includes 132 references.
77 citations
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TL;DR: In this paper, the preparation methods and reactions of isoxazoles are described and systematized on the basis of analysis of the literature published from 2005 to present, and major attention is focused on the most efficient approaches: condensation of hydroxylamine with 1,3-dielectrophiles and reactions with nitrile oxides with alkenes and alkynes.
Abstract: The preparation methods and reactions of isoxazoles are described and systematized on the basis of analysis of the literature published from 2005 to present. In the discussion of synthesis, major attention is focused on the most efficient approaches: condensation of hydroxylamine with 1,3-dielectrophiles and reactions of nitrile oxides with alkenes and alkynes. Five-membered ring opening reactions leading to acyclic functionalized or other heterocyclic compounds are considered. The transformations of isoxazole derivatives that occur without ring cleavage to form fused heterocyclic systems, as well as reactions that lead to the introduction of C-substituents into isoxazoles, are considered. Data on the biological activity of some isoxazole derivatives are reported. The bibliography includes 439 references.
70 citations
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TL;DR: The possibilities of electrochemical synthesis of nanostructures and nanomaterials are considered in this article, and the problems and prospects of the development of research in this field are discussed.
Abstract: The possibilities of electrochemical synthesis of nanostructures and nanomaterials are considered. The problems and prospects of the development of research in this field are discussed. Electrosynthetic methods are classified, their specific features and advantages are demonstrated in comparison with other physical and chemical methods. Examples of electrosynthesis of nanomaterials and their use in various devices are offered. The bibliography includes 613 references.
65 citations
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TL;DR: Modern methods for immunoglobulin engineering and promising strategies for the creation and applications of monoclonal antibodies, their derivatives and analogues, including abzymes and scaffolds, oriented to the use in the diagnosis and targeted therapy of cancer and other socially significant diseases are covered.
Abstract: The review outlines progress and problems in the design of non-natural antibodies for clinical applications over the past 10–15 years. The modular structure of natural antibodies and approaches to its targeted modifications and combination with other structural elements and effector molecules are considered. The review covers modern methods for immunoglobulin engineering and promising strategies for the creation and applications of monoclonal antibodies, their derivatives and analogues, including abzymes and scaffolds, oriented to the use in the diagnosis and targeted therapy of cancer and other socially significant diseases. The bibliography includes 225 references.
56 citations
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56 citations
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TL;DR: The role of the heterogeneity of the sensor/sample systems is emphasized, and it is shown that due to this heterogeneity such sensors respond to the analyte activities rather than to concentrations as mentioned in this paper.
Abstract: The recent advances in the theory and practice of potentiometric, conductometric and optical sensors based on ionophores are critically reviewed. The role of the heterogeneity of the sensor/sample systems is emphasized, and it is shown that due to this heterogeneity such sensors respond to the analyte activities rather than to concentrations. The basics of the origin of the response of all three kinds of ionophore-based sensors are briefly described. The use of novel sensor materials, new preparation and application techniques of the sensors as well as advances in theoretical treatment of the sensor response are analyzed using literature sources published mainly from 2012 to 2014. The basic achievements made in the past are also addressed when necessary for better understanding of the trends in the field of ionophore-based sensors. The bibliography includes 295 references.
54 citations
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53 citations
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TL;DR: In this article, a review discusses the mechanisms of reactions involved in the heavy feedstock hydroprocessing, the presumed structure and state of the catalytically active components and methods for the formation of supports with the desired texture.
Abstract: A grave problem of modern oil refining industry is continuous deterioration of the produced oil quality, on the one hand, and increase in the demand for motor fuels, on the other hand. This necessitates processing of heavy oil feedstock with high contents of sulfur, nitrogen and metals and the atmospheric residue. This feedstock is converted to light oil products via hydrogenation processes catalyzed by transition metal compounds, first of all, cobalt- or nickel-promoted molybdenum and tungsten compounds. The processing involves desulfurization, denitrogenation and demetallization reactions as well as reactions converting heavy hydrocarbons to lighter fuel components. The review discusses the mechanisms of reactions involved in the heavy feedstock hydroprocessing, the presumed structure and state of the catalytically active components and methods for the formation of supports with the desired texture. Practically used and prospective approaches to catalytic upgrading of heavy oil feedstock as well as examples of industrial processing of bitumen and vacuum residues in the presence of catalysts are briefly discussed. The bibliography includes 140 references.
49 citations
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TL;DR: In this article, the physicochemical properties of these compounds are presented in accordance with the up-to-date classification of their structures, and the development of new and advancement of traditional methods for determination of natural phenolic antioxidants in relation to public health protection problems.
Abstract: Published data of the last decade on the chemical analysis and related problems of investigation of phenolic antioxidants as components of complex biomedical and food objects are generalized. The physicochemical properties of these compounds are presented in accordance with the up-to-date classification of their structures. Particular attention is paid to the development of new and advancement of traditional methods for determination of natural phenolic antioxidants in relation to public health protection problems. The interdisciplinary character of the considered problems is emphasized and the ways for problem solution are outlined. The bibliography includes 380 references.
49 citations
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TL;DR: In this paper, the dependence of the structure and properties of CdS nanoparticles on the nanoparticle size is illustrated, and the possibility of utilizing CcS quantum dots as biological labels and sensitizers for solar cells is analyzed.
Abstract: Key results of recent studies on cadmium sulfide nanoparticles are systematized. The dependence of the structure and properties of CdS nanoparticles on the nanoparticle size is illustrated. The possibility of utilizing CdS quantum dots as biological labels and sensitizers for solar cells is analyzed. The principles, features and potential of the method of aqueous solution deposition are described from the standpoint of synthesis of CdS nanocrystals and hybrid forms based on them with specified structure and properties.The bibliography includes 180 references.
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TL;DR: In this article, the key achievements in the determination of trace amounts of components in environmental samples (soils, ores, natural waters, etc.) by laser-induced breakdown spectrometry are considered.
Abstract: The key achievements in the determination of trace amounts of components in environmental samples (soils, ores, natural waters, etc.) by laser-induced breakdown spectrometry are considered. Unique capabilities of this method make it suitable for rapid analysis of metals and alloys, glasses, polymers, objects of cultural heritage, archaeological and various environmental samples. The key advantages of the method that account for its high efficiency are demonstrated, in particular, a small amount of analyzed material, the absence of sample preparation, the possibility of local and remote analysis of either one or several elements. The use of chemometrics in laser-induced breakdown spectrometry for qualitative sample classification is described in detail. Various approaches to improving the figures of merit of quantitative analysis of environmental samples are discussed. The achieved limits of detection for most elements in geochemical samples are critically evaluated. The bibliography includes 302 references.
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TL;DR: In this paper, the role of symmetry and the regular distribution of heavy atoms in the formation of stable crystal structures, which is to be taken into account in the targeted design, is considered.
Abstract: The method of crystallographic analysis relies on the mechanical-wave concept that treats the crystalline state as the result of ordering of atomic positions by families of parallel equidistant planes. Using this method, a large set of fluoride, oxide and sulfide structures was analyzed. The pseudo-translational ordering of various atomic groups (including the presence of cation and anion sublattices) in the structures of various classes of inorganic compounds was established. The crucial role of local ordering of heavy cations (coherent assembly) in the structures comprising large cluster fragments (Keggin polyanions, polyoxoniobates, etc.) is discussed. The role of symmetry and the regular distribution of heavy atoms in the formation of stable crystal structures, which is to be taken into account in the targeted design, is considered. The universality of configurations of atomic positions in the structures of various classes of inorganic compounds resulting from the ordering mechanism organized by mechanical (elastic) forces is demonstrated. The bibliography includes 158 references.
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TL;DR: In this article, the authors highlight recent advances in experimental and theoretical chemistry dealing with investigation of the electronic structures and physicochemical properties of planar hetero-annulated cyclooctatetraenes.
Abstract: The present review highlights recent advances in experimental and theoretical chemistry dealing with investigation of the electronic structures and physicochemical properties of hetero[8]circulenes. These compounds are the only representatives of planar heteroannulated cyclooctatetraenes. It is shown that high molecular symmetry of hetero[8]circulenes and the extended specific π-conjugated chain are the main factors responsible for high stability of the crystal packing modes and the optical and magnetic properties of these compounds. These effects also determine numerous selection rules for electronic and vibrational transitions in UV-Vis, IR and Raman spectra. Emphasis is given to the aromaticity of hetero[8]circulenes containing the inner antiaromatic cyclooctatetraene core. The planar structure of the latter is stabilized by a polyaromatic system composed of benzene rings and five-membered heterocycles. Due to high thermal and chemical stability of most hetero[8]circulenes combined with semiconducting properties, these compounds can be considered as promising materials for molecular electronics and nanophotonics, in particular for the production of organic light-emitting diodes and field-effect transistors. The bibliography includes 154 references.
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TL;DR: In this article, a review is devoted to analysis and generalization of the results of quantum chemical studies on the structure, chemical bonding and intermolecular interactions in coordination compounds of tetravalent silicon, germanium and tin in crystals, in solutions and in the gas phase.
Abstract: The review is devoted to analysis and generalization of the results of (i) quantum chemical studies on the structure, chemical bonding and intermolecular interactions in coordination compounds of tetravalent silicon, germanium and tin in crystals, in solutions and in the gas phase and (ii) experimental investigations of the electron density distribution in these systems. The bibliography includes 147 references.
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TL;DR: In this paper, the most promising methods for the synthesis of functionally substituted cyclopropanes, namely, the electrocatalytic cascade and multicomponent transformations of CH acids and also the joint electrolysis of CH acid and activated alkenes or carbonyl compounds in the presence of alkali metal halides as mediators, are discussed.
Abstract: Data on methods of electrochemical synthesis of cyclopropanes are summarized and described systematically. Direct electrochemical methods to afford cyclopropanes in both cathodic and anodic processes are considered. Among indirect electrochemical methods such as the processes employing electrogenerated bases and also those involving electrogenerated metal complexes, attention is focused on the most promising methods for the synthesis of functionally substituted cyclopropanes, namely, the electrocatalytic cascade and multicomponent transformations of CH acids and also the joint electrolysis of CH acids and activated alkenes or carbonyl compounds in the presence of alkali metal halides as mediators. The bibliography includes 62 references.
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TL;DR: In this paper, a review of methods of synthesis of nanopowders, nanowires and films based on titanium, zirconium and hafnium diborides is presented.
Abstract: The review is concerned with methods of synthesis of nanopowders, nanowires and films based on titanium, zirconium and hafnium diborides. Methods for consolidation of nanoparticles in order to prepare bulk nanostructured samples are analyzed. Information on the physicochemical and physicomechanical properties of these systems is generalized and the role of the size effects is analyzed. Data on the thermal stability and influence of radiation, deformation and corrosion on the TiB2-, ZrB2- and HfB2-based nanostructures are presented. Poorly studied aspects of the title field of research are pointed out. The bibliography includes 130 references.
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TL;DR: In this article, the reductive alkylation of amines with carbonyl compounds is described systematically and the effect of the reactant and catalyst structures on the reaction rates and chemo-and stereo-selectivity is considered.
Abstract: Available data on the reductive alkylation of amines with carbonyl compounds ? a key method for the preparation of secondary and tertiary amines ? are described systematically. The review provides information on the relevant reducing agents and catalysts and on the use of chiral catalysts in stereo- and enantiocontrolled reactions of amine synthesis. The effect of the reactant and catalyst structures on the reaction rates and chemo- and stereo(enantio)selectivity is considered. The bibliography includes 156 references.
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TL;DR: In this paper, the design and properties of nanocomposite fibrous materials and methods for modification and functionalization of fiber surface are discussed, and the prospects for the application of non-woven materials for biotissue engineering and for the development of smart materials are considered.
Abstract: Published data on nanostructured materials prepared by electrospinning are analyzed and generalized. Particular attention is devoted to the design and properties of nanocomposite fibrous materials and methods for modification and functionalization of fibre surface. The prospects for the application of non-woven materials for biotissue engineering and for the development of smart materials are considered. The bibliography includes 330 references.
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TL;DR: The review is devoted to the latest achievements in the design of dual action antibiotics ?
Abstract: The review is devoted to the latest achievements in the design of dual action antibiotics ? heterodimeric (chimeric) structures based on antibacterial agents of different classes (fluoroquinolones, anthracyclines, oxazolidines, macrolides and so on). Covalent binding can make the pharmacokinetic characteristics of these molecules more predictable and improve the penetration of each component into the cell. Consequently, not only does the drug efficacy increase owing to inhibition of two targets but also the resistance to one or both antibiotics can be overcome. The theoretical grounds of elaboration, design principles and methods for the synthesis of dual action antibiotics are considered. The structures are classified according to the type of covalent spacer (cleavable or not) connecting the moieties of two agents. Dual action antibiotics with a spacer that can be cleaved in a living cell are considered as dual action prodrugs. Data on the biological action of heterodimeric compounds are presented and structure?activity relationships are analyzed. The bibliography includes 225 references.
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TL;DR: In this article, the formation of highly concentrated emulsions is treated as the concentration glass transition leading to suppression of the molecular and supermolecular mobility and subsequently to the existence of a solid-like state of the systems in question.
Abstract: The review concerns modern physicochemical, chemical and physical approaches to research into structural features that determine the rheological properties of highly concentrated emulsions. The structures and properties of various systems (suspensions, emulsions as well as transient forms including micellar colloidal solutions) are considered. The formation of highly concentrated emulsions is treated as the concentration glass transition leading to suppression of the molecular and supermolecular mobility and, subsequently, to the existence of a solid-like state of the systems in question. The emphasis is placed on analysis of visco-plasticity which manifests itself in the possibility for emulsions (unlike suspensions) to undergo irreversible deformation (to flow) at stresses exceeding some threshold (critical value) called the yield stress. The thixotropic nature of the transition through the yield stress, governed by the kinetics of the breakup/recovery of the inherent structure is considered in detail. It has been shown that structure formation in highly concentrated emulsions can extend to a macroscopic level and result in the onset of heterogeneity of a flow in the form of shear bands. The bibliography includes 202 references.
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TL;DR: In this paper, the application of C2-symmetric diamines and their derivatives as organocatalysts for asymmetric reactions (aldol, Michael, Mannich, Diels-Alder reactions, desymmetrization, allylation, etc.).
Abstract: The review is devoted to the application of C2-symmetric diamines and their derivatives as organocatalysts for asymmetric reactions (aldol, Michael, Mannich, Diels–Alder reactions, desymmetrization, allylation, etc.). Amino acid derivatives, di- and polyamides (sulfamides), bisureas, bisthioureas, bisamidines and bisguanidines are considered. Significant attention is given to the effect of the catalyst structure on the mechanism of catalytic action. Successful applications of such catalysts in enantioselective synthesis of chiral biologically active compounds are summarized. The bibliography includes 181 references.
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TL;DR: In this paper, the properties of hybrid nanomaterials with various morphology (with core?shell structures, with encapsulated metal nanoparticles, and with metal nano-particles on the surface) are discussed.
Abstract: Hybrid nanostructures representing combinations of different materials and possessing properties that are absent in separate components forming the hybrid are discussed. Particular attention is given to hybrid structures containing plasmonic and magnetic nanoparticles, methods of their synthesis and the relationship between the composition, structure and properties. The functional features of the hybrid nanomaterials of various morphology (with core?shell structures, with encapsulated metal nanoparticles and with metal nanoparticles on the surface) are considered. The unique properties of these hybrid materials are demonstrated, which are of interest for solving problems of catalysis and photocatalysis, detecting impurities in various media, in vivo visualization, bioanalysis, as well as for the design of optical labels and multifunctional diagnostic nanoplatforms. The bibliography includes 182 references.