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A [3 + 2] cycloaddition reaction using dialkyne and diazide comonomers, both bearing explosophoric groups, to synthesize energetic polymers containing furazan and 1,2,3-triazole ring as well as nitramine group in the polymer chain have been described. The developed solvent- and catalyst-free approach is methodologically simple and effective, the comonomers used are easily available, and the resulting polymer does not need any purification. All this makes it a promising tool for the synthesis of energetic polymers. The protocol was utilized to generate multigram quantities of the target polymer, which has been comprehensively investigated. The resulting polymer was fully characterized by spectral and physico-chemical methods. Compatibility with energetic plasticizers, thermochemical characteristics, and combustion features indicate the prospects of this polymer as a binder base for energetic materials. The polymer of this study surpasses the benchmark energetic polymer, nitrocellulose (NC), in a number of properties.

Here we report the first synthesis of two diastereomeric cationic octahedral Co(III) complexes based on commercially available (R,R)-1,2-diphenylethylenediamine and salicylaldehyde. Both diastereoisomers with opposite chiralities at the metal center (Λ and Δ configurations) were prepared. The new Co(III) complexes possessed both acidic hydrogen-bond donating (HBD) NH moieties and nucleophilic counteranions and operate as bifunctional chiral catalysts for the challenging kinetic resolution of terminal and disubstituted epoxides by the reaction with CO2 under mild conditions. The highest selectivity factor (s) of 2.8 for the trans-chalcone epoxide was achieved at low catalyst loading (2 mol %) in chlorobenzene, which is the best achieved result currently for this type of substrate.

New methylpalladium chloride complex with bulky N,N'-bis(1,2,3,4-tetrahydro-1-naphthyl)-substituted glyoxal diimine ligand was obtained. This complex was found to be an efficient catalyst for vinyl-addition polymerization of norbornene derivative and for polymerization of a diazoacetate, giving polycarbenes with side polar functionalities.

A supramolecular complex (SFBZ) of fenbendazole (FBZ) with licorice extract and sodium dioctyl sulfosuccinate is prepared by mechanochemical method, and its anthelminthic activity and metabolism in sheep are studied. Physicochemical studies of SFBZ confirmed its improved solubility and a decrease in the particle size. FBZ and its metabolites are found to display enhanced absorption into the bloodstream. Their maximum concentration in the blood increases by a factor of 2.3–2.5, and the time required to reach this level increases. The efficacy of SFBZ on the laboratory model of Trichinella spiralis infection is 96.27% at a dose of 1 mg/kg a.i. (active ingredient), whereas the efficacy of the FBZ substance administered at the same dose is 13.70%. A single oral dose of 2.0 mg/kg (a.i.) of SFBZ is highly effective against nematodes in naturally infected sheep, as fecal analyses showed; while the FBZ substance revealed 95.97% efficacy at a dose of 5.0 mg/kg. The higher activity of SFBZ is related to its increased solubility and improved absorption in the animal body.

Solid dispersions of medamine and albendazole with water-soluble polymers (PVP, arabinogalactan) were obtained by mechanochemical technology to increase the aqueous solubility of poorly soluble anthelmintic drug substances. An analysis of solid dispersions of drug–polymer systems showed that their solubilities depended on the nature of both the drug and polymer. The aqueous solubilities of medamine and albendazole could be increased by greater than 50 and 27 times, respectively, by varying the joint processing time with the polymers. An analysis of IR spectra and a comparison of them with published data suggested that intermolecular complexes were formed in these systems. Innovative anthelmintic drugs with increased solubility for medicine and veterinary medicine could be created by using the proposed mechanochemical technology for obtaining solid dispersions. The resulting solid dispersions had several advantages over conventional dosage forms, in particular, they were obtained in one stage, their preparation did not require excipients (dispersants, surfactants, wetting agents, etc.), and they were more conveniently used and inexpensively priced.

New magnetic nanomaterials based on soluble ferrocene-containing polyphenylenes were synthesized at 20–80 °C both under normal conditions and under ultrasonic irradiation. The maximum magnetization of nanomaterials containing magnetite nanoparticles was 15 G cm3 g−1 in a magnetic field of 2.5 kOe. According to transmission electron microscopy, the average statistical sizes of magnetic nanoparticles were in the range of 12–19 nm.

Here we report the first synthesis of two diastereomeric cationic octahedral Co(III) complexes based on commercially available (

High molecular weight block terpolymers with different contents of polypropylene carbonate and cyclohexene carbonate units in the polymer chain were synthesized by the copolymerization of carbon dioxide, propylene oxide, and cyclohexene oxide. Zinc adipate was used as a catalyst. The terpolymerization products were characterized by 1H and 13C NMR spectroscopy, IR spectroscopy, GPC, DSC, and DMA methods. The influence of the reaction conditions on the composition, microstructure, and molecular-weight and thermal characteristics was studied.

Air environment status is the most serious problem in the town of Sterlitamak (Russian Federation). The situation is aggravated by the fact that in the conditions of industrial town exist some unfavorable factors. They contribute to the accumulation of emissions from industrial facilities and transport means in the open air. An integrated approach is required to effectively address air basin pollution. This approach should provide for reliable assessment of the air pollution, as well as the development and creation of the systems for monitoring and managing the quality of air basin of the district, the town and the adjacent territory. The article describes the current state of landscaping in Sterlitamak. A lag in the pace of landscaping from the pace of construction which leads to the unsatisfactory state of atmospheric air is revealed. The issues of formation of full-fledged human habitat, in particular, landscaping of territories, are considered. The methods of the monitoring and structuring green spaces which allow increasing in the level of ecological comfort of the environment of industrial town are substantiated. The measures of improving the state of the atmospheric air, such as introduction of unified system of green spaces, landscaping of the sanitary protection zones (SPZ), increasing the number of green spaces in residential areas and landscaping of the railway transport routes are proposed. It is determined that the designing of landscaping of SPZ should be carried out taking into account the nature of industrial pollution, as well as local climatic and topographic conditions. The plants used for landscaping these areas must be sanitary effective and sufficiently resistant to air and soil pollution by industrial emissions. Recommendations on selection of green spaces that contribute to good aeration of the territory and prevent the penetration of harmful emissions into the residential area are given.

Spray drying is appropriate for the preservation of halophilic microorganisms due to the nature of these microorganisms, as they survive in adverse environmental conditions by being encapsulated in salt crystals. Artificial neural networks were in this study used to optimize practically significant spray-drying regimes of the C50-carotenoids producer Halobacterium salinarum. Immediately after drying, the samples contained up to 54% halobacterial biomass and less than 5% moisture, and the level of preservation of carotenoids was 95–97%. The storage of biomass at 4 °C resulted in the gradual degradation of the carotenoids, which reached 58–64% in the best samples after 1 year. A comprehensive study of changes in halobacteria biomass after spray drying and the nature of the damage provided new data on the survival and preservation of cells and biologically active substances in the various spray-drying regimes and at different storage times.

The interaction between cyclodextrins (β- and γ-CD) and ferrocenyl azoles (i.e., pyrazole ferrocenes (I, III–V) and benzimidazole ferrocenes (VI, VII)), along with 1-ferrocenylethanol (II), each in the form of (R)- and (S)-enantiomers, in forming inclusion complexes is studied for the first time using detailed quantum chemical calculations. Compounds are calculated in terms of the density functional theory (DFT), using the Becke–Lee–Yang–Parr (B3LYP) approach in the 6-31G* basis sets. For the considered CD complexes with enantiomers of I–VII, structures in which a guest partially enters a host cavity from the side of the heterocyclic substituent (pyrazole or benzimidazole) are found to be energetically advantageous. It is shown that for successful resolution of (R,S)-enantiomers on chiral phases containing cyclodextrins, we must consider the interaction between outer hydroxyl groups on the CD cone’s surface, in addition to the correspondence of geometric dimensions. The calculated data correlate well with the data from the chromatographic separation of guest enantiomers on cyclodextrin sorbents.

The thermodynamic characteristics of the adsorption of several 1,3,4-oxadiazoles and 1,2,4,5- tetrazines from methanol and water-methanol solutions onto neutral hypercrosslinked polystyrene with a degree of crosslinking of 150% are determined via high performance liquid chromatography. It is shown how the obtained characteristics depend on the molecular structure of adsorbed substances and the composition of the liquid phase in which adsorption occurs.

Study of the main physicochemical features of the sorption of phenylamide adamantane derivatives on hyper-cross-linked polystyrene from water–acetonitrile solutions shows that both hydrophobic and electronic interactions make a large contribution to retention, especially for a chlorine-containing derivative in which there are π–p and π–d interactions between the outer-shell electrons of the chlorine atom in addition to π–π interactions between aromatic fragments of the sorbate and sorbent.

The article presents the results of 257 robot-assisted radical prostatectomies, 135 partial nephrectomies and 32 radical nephrectomies at the period from 2010 to 2016. The operations were performed on robotic complex da Vinci S. The mean operative time was 170±50 min, 158,4±72,2 min and 143,3±67,3 min, the mean blood loss was 130±35 ml, 213,0±102,2 ml and 141,4±49,0 ml for robotic radical prostatectomy, partial and radical nephrectomy, respectively. The mean time of warm ischemia consisted of 13,1±2,7 min. Five-year cancer-specific survival rate was 100%, 100% and 98%. The overall survival rate was 97,5%, 87% and 92% for robotic radical prostatectomy, partial and radical nephrectomy, respectively.

are presented of measurements carried out to determine elastic wave velocity in the rock massif in the bed of the Sayano-Shushenskaya HPP. A significant increase has been noted in longitudinal and transverse wave velocities and in the thickness of exogenous zones, as compared to values obtained during the survey phase and determined in the post-construction period. One of the principal reasons for the observed change in the thickness and properties of zones (subzones) of diverse rock massif integrity in the dam bed is the technogenic stresses transmitted by the facility to the massif. Changes that trend (i.e., occur unidirectionally over time) and vary due to variations in reservoir water level were identified in the properties and state of the massif under study.

The results are presented of the major activities undertaken by the Geodynamic Research Centre during the final stage of Boguchanskaya hydroproject construction.

The condensation of 1-(ferrocenylalkyl)pyrazole-3-carbaldehydes with 4′-aminotetraphenylporphyrin, followed by reduction with NaBH(OAc)3 in 1,2-dichloroethane, provides a convenient method for the synthesis of 5-{4-[({1-[1-(ferrocen-1-yl)alkyl]-5-methyl-1H-pyrazol-3-yl}methyl)amino]phenyl}-10,15,20-triphenylporphyrins which exhibit pronounced cytotoxicity against Staphylococcus aureus under ultrasonic irradiation.

The article proposes a unified principle of permutation decoding (PD), which applies to redundant systematic block codes. This method allows using correction capabilities of such codes, but in the classical interpretation, the method requires cumbersome matrix calculations, which does not allow using the positive properties of the error correction method. The computing process is excessively complex. Therefore, to reduce the negative effect in the PD system, it is proposed to use the cognitive principle of data processing at the channel level, which significantly reduces the decoder complexity and ensures PD application in the air passenger biometric data systems.

The article presents the results of 257 robot-assisted radical prostatectomies, 135 partial nephrectomies and 32 radical nephrectomies at the period from 2010 to 2016. The operations were performed on robotic complex da Vinci S. The mean operative time was 170±50 min, 158,4±72,2 min and 143,3±67,3 min, the mean blood loss was 130±35 ml, 213,0±102,2 ml and 141,4±49,0 ml for robotic radical prostatectomy, partial and radical nephrectomy, respectively. The mean time of warm ischemia consisted of 13,1±2,7 min. Five-year cancer-specific survival rate was 100%, 100% and 98%. The overall survival rate was 97,5%, 87% and 92% for robotic radical prostatectomy, partial and radical nephrectomy, respectively.

The adsorption selectivities of a series of organic compounds from solutions on hyper-cross-linked polystyrene networks (HPNs) with ultimate degrees of cross linking were studied by high performance liquid chromatography (HPLC). The thermodynamic characteristics of adsorption (TCA) of substances under study from water–organic solutions on such HPNs in the Henry region were determined. The TCAs of organic compounds on the HPNs under study as a function of their molecular structures are discussed. It was established that the magnitude of the Gibbs energy change upon adsorption increases with increasing the number of π-electrons in the adsorbed molecules in a series of both aromatic hydrocarbons and their sulfurcontaining heterocyclic analogs. As an example, a model mixture of organic compounds was separated on HPNs by HPLC. It was shown that middle and heavy oil fractions can be fractionated on HPNs into the groups of mono-, di-, and tricyclic aromatic compounds.

Monodisperse styrene–divinylbenzene (1 wt %) copolymer microbeads are obtained via the elaborate method of high-productivity precipitation polymerization. The crosslinking of this copolymer with chloromethyl methyl ether in the presence of Friedel–Crafts catalyst yields porous hypercrosslinked polymers with degrees of crosslinking that range from 200 to 500%. Microbead sorbents are shown to be suited for selective stationary phases for high-performance liquid chromatography and supercritical fluid chromatography.

The main organic impurities in concentrated solutions of sodium thiocyanate in different steps of production of polyacrylonitrile fiber were identified, and the possibility of their efficient removal simultaneously with iron salts by commercial sorbents of neutral hypercrosslinked polystyrene type was demonstrated.

The authors suggested a new method of performance of open, laparoscopic and robot-assisted partial nephrectomy using specially developed instruments for selective parenchyma clamping in order to improve the functional results of renal cell carcinoma treatment. The operation with clamping of renal vessels was carried out in 86 cases and clamping of renal parenchyma was used in 24 cases. It was shown, that the open, laparoscopic and robot-assisted partial nephrectomy could be safely performed in conditions of selective ischemia of the renal parenchyma without clamping of renal vessels.

ISSN 00125016, Doklady Physical Chemis try, 2015, Vol. 462, Part 2, pp. 135–139. © Pleiades Publishing, Ltd., 2015.Original Russian Text © B.R. Saifutdinov, V.A. Davankov, G.A. Petukhova, M.P. Tsyurupa, Z.K. Blinnikova, M.M. Il’in, 2015, published in Doklady Akademii Nauk, 2015,Vol. 462, No. 6, pp. 675–680.

A series of N-ferrocenylalkyl pyrroles were synthesized by intermolecular redox amination of ferrocenyl ketones and formylferrocene with pyrroline. The racemic mixtures were separated into enantiomers using high performance liquid chromatography. The structure of N-ferrocenylmethylpyrrole was determined by X-ray diffraction.

Carbonyl derivatives of N-ferrocenyl alkyl pyrazoles were synthesized. The techniques of analytical separation of racemates of the synthesized compounds were developed. The structures of three compounds were determined by X-ray diffraction analysis.

A series of Schiff bases obtained from salicylaldehydes and 3,3′-diformyl-BINOL were synthesized. The complexes of these Schiff bases with Ti(IV) were active for the asymmetric ring opening of epoxides with TMSCN. A mixture of unpurified ligands was found to be as effective as the best one. The influence of temperature, solvent polarity and structural modification of the pre-catalysts on the enantioselectivity of the process has also been investigated.

The sorption of a series of aromatic heterocycles on neutral hypercrosslinked polystyrene from maximally dilute acetonitrile and water.acetonitrile solutions of them is investigated by high-performance liquid chromatography in a range of column temperatures from 308 to 348 K at 5 K intervals. It is found that for all heterocycles, the logarithm of the retention factor versus the reciprocal of the temperature dependences can be approximated by linear functions with r 2 ≥ 0.999. It is established that the true compensation effect (which does not result from the correlation between enthalpy and entropy determination errors) occurs during the sorption of heterocycles on hypercrosslinked polystyrene from both acetonitrile and water-acetonitrile solutions. It is shown that in the compensation diagram, the points corresponding to sorbates are grouped together according to the type of sorbate-sorbent interactions. It is found that changes in the Gibbs energy, enthalpy, and entropy of sorption from acetonitrile solutions and for sorption from water-acetonitrile solutions are related to one another by linear dependences.

The structures, electrochemical properties, enantiomeric separation of ferrocenyl-(alkyl)pyrimidines and ferrocenyl(ethyl)adenine and their effects on the DNA synthesis in tumor cells were studied. Enantiomeric mixtures were separated by HPLC on modified cellulose as the chiral selector. The electrochemical properties of compounds were studied by cyclic voltammetry. All compounds have reversible single-electron redox transition in the region of 0.52–0.60 V, which belongs to ferrocene—ferrocenium with a positive shift compared to ferrocene (0.52 V). The molecular structure of 1-N-(ferrocenylbenzyl)-5-iodocytosine was studied by X-ray diffraction. 1-N-(Ferrocenylethyl)adenine was studied for ability to inhibit the DNA synthesis in the human ovarian cancer cell culture by the 3H-thymidine test.

The principles, procedures, and results of construction of a detailed three-dimensional geologic-engineering model of the rock mass in the bed of the arch-gravity dam at the Sayano-Shushenskaya HPP, and also methods of transforming this model into individual geomechanical models of the mass under investigation — models of the elastic, deformation, and strength properties, which are used in performing a series of check analyses of the stress-strain state of the “dam-bed-reservoir” system and evaluating the stability of the dam at the Sayano-Shushenskaya HPP are discussed.

The results from chromatographic analysis of biologically active isatin derivatives on hyper-crosslinked polystyrene (HCLPS) and silica gel modified by octadecyl groups (SilC18) are presented. The constants of distribution of sorbates between a mobile phase and the investigated sorbents (Kx) and the changes in the standard differential molar Gibbs energies of adsorption \((\Delta _a \bar G^\circ )\) are calculated, along with the chromatographic retention-physicochemical property of sorbate dependences. It is found that the equations describing these dependences have high forecasting ability with respect to the values of retention factors of the investigated sorbates.

A series of Co(III) anionic complexes of Schiff bases obtained from salicylaldehydes and enantiomerically pure amino acids has been synthesized. The outersphere counterion was exchanged by H+ and the novel chiral Bronsted acids were used to induce asymmetry into an aza-Diels–Alder reaction. The influence of the temperature, solvent polarity, and structural modification of the chiral anions on the enantioselectivity of the process has also been investigated.

Aza-Michael reaction of ( E )-4-(diphenylphosphoryl)but-3-en-2-one with mono- and bicyclic nitrogen heterocycles proceeds regioselectively in the absence of catalysts to give the corresponding s-diphenylphosphoryl-b-azahetarylalkanones. Its reaction with imidazole in the presence of chiral organocatalysts affords the corresponding enantiomerically enriched adduct in higher yield.

Consider a boundary-value problem for a second-order linear elliptic equation in a bounded domain. The coefficient of the required function is nonpositive everywhere in the domain, except for a small neighborhood of an interior point. The following question arises: Under what constraints on this coefficient in the given small domain do the statements on the existence and uniqueness of the solution of the first boundary-value problem remain valid?

The efficient, high-yield approaches to two novel regioisomeric salicyl aldehyde analogs, 4-formyl-13-(2-hydroxyphenyl)-[2.2]paracyclophane and 4-formyl-12-(2-hydroxyphenyl)-[2.2]paracyclophane (iso-FHPhPC and pseudo-FHPhPC, respectively), constructed on the basis of an aryl[2.2]paracyclophane backbone are described. The key stage of the backbone formation is the Suzuki cross-coupling of paracyclophanyl halides with arylboronic acids. Efficient procedures for the resolution of the racemic hydroxy aldehydes into enantiomers via Schiff bases with enantiomers of α-phenylethyl amine were elaborated, and the absolute configurations of enantiomers were established on the basis of X-ray analysis of diastereomeric imines. Starting from these chiral hydroxy aldehydes the first representatives of bi-, tri-, and tetradentate phenoxy-imine ligands belonging to an aryl[2.2]paracyclophane family were obtained. The induction power of the ligands was tested in the Et2Zn asymmetric addition to aldehydes.

The heating of the 18-electron complex [3,3-(dppb)-3-H-3-Cl-closo-3,1,2-RuC(2)B(9)H(11)] (3) in benzene at 80 °C in the presence of a small amount of CCl(4) as initiator afforded paramagnetic 17-electron species [3,3-(dppb)-3-Cl-closo-3,1,2-RuC(2)B(9)H(11)] (4) along with minor amounts of two P-phenylene ortho-cycloboronated derivatives [3-Cl-3,3,8-{Ph(2)P(CH(2))(4)PPh-μ-(C(6)H(4)-ortho)}-closo-3,1,2-RuC(2)B(9)H(10)] (5) and [3,7-Cl(2)-3,3,8-{Ph(2)P(CH(2))(4)PPh-μ-(C(6)H(4)-ortho)}-closo-3,1,2-RuC(2)B(9)H(10)] (6) in total yield of ca. 80%. The heating of either 3 or 4 in toluene at 95 °C in the absence of CCl(4) led to the selective formation of 5, which was isolated in 64% and 46% yield, respectively. Thermolysis of 3 at higher temperatures (boiling toluene, 110 °C) gives novel paramagnetic species [3-Cl-3,3,7,8-{Ph(2)P(CH(2))(4)P-μ-(C(6)H(4)-ortho)(2)}-closo-3,1,2-RuC(2)B(9)H(9)] (7) featuring bis(ortho-cycloboronation) of both P-phenyl groups at the same phosphorus atom of the ruthenium-bound dppb ligand. All new paramagnetic complexes 4-7, as well as starting diamagnetic species 3, were characterized by single-crystal X-ray diffraction and, in addition, by EPR spectroscopic studies of odd-electron complexes. Ruthenacarboranes 3-5 and 7 all display high efficiency as catalysts for the atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA). Complex 5 gave the best catalyst performance in terms of polydispersity; the PDI (M(w)/M(n)) of the polymer samples is as low as 1.15.

The sorption of first synthesized indole derivatives by highly cross-linked polystyrenes from water-acetonitrile solutions was studied by high-performance liquid chromatography. The retention factors and differences in the Gibbs energy of adsorption from infinite diluted solutions were calculated, and the applicability of the Snyder-Soczewinski and Scott-Kucera models for describing the chromatographic retention of sorbates on a polymer network of highly cross-linked polystyrene was shown.

Terpolymers with different L-lactic acid contents in the poly(propylene carbonate) chain were synthesized by the terpolymerization of carbon dioxide, propylene oxide and L-lactide, catalyzed by zinc adipate. The terpolymerization products were characterized by 1 H and 13 C NMR, 2D { 1 H- 13 C} HMBC and FT-IR spectroscopy, DSC, TGA and GPC.

Homogeneous time series of atmospheric precipitation with corrected systematic errors of measurements at 100 stations in Russia for the period of 1936–2000 are obtained. Combined effects are considered of all kinds of systematic errors of standard network precipitation-measuring instruments (the raingauge with the Nifer shield and the Tret’yakov raingauge) on the measured precipitation totals. Comparative analysis is carried out of the measured and corrected long-term mean characteristics of precipitation amounts (annual totals, warm and cold season totals, and different types of precipitation). On the basis of the obtained archives of precipitation homogeneous time series, linear trends are estimated for the period under consideration with estimation of their statistical significance. Schematic charts are plotted and analyzed of time changes in the annual precipitation amounts and in the amounts of different types of precipitation.