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Transformations of pine wood during exposure to ozone were studied. The content of lignin and cellulose in the cellulose-containing material (CCM) from ozonated wood was determined. The polymerization degree (PD) of cellulose from CCM was determined. The CCM samples were examined by diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy and X-ray diffraction (XRD) analysis. HPLC analysis of water-soluble lignin ozonolysis products was performed. Wood ozonation leads to lignin destruction; 40–42% delignification degree is achieved. The destruction of aromatic components is confirmed by DRIFT spectra. A decrease in the intensity of skeletal vibrations of aromatic ring at 1511 and 1598 cm–1, bands at 1662 cm–1, and an increase in the intensity of stretching C=O vibrations of lignin and hemicelluloses (HCs) at 1736 cm–1 were observed. The stoichiometric ratio of the amount of absorbed ozone and the destroyed guaiacyl units, as well as the composition of water-soluble products, shows that ozonolysis is the main mode of wood lignin destruction. The XRD data and a decrease in PD of cellulose show that, in addition to lignin, HCs and amorphous cellulose are also destroyed during ozonation. It has been found that the region of ozone specific absorption ≤1.5 mmol O3/g corresponds to the most efficient destruction of lignin with the lowest degradation of cellulose fiber.

Nitrogen-doped carbon nanomaterials show unique properties in catalysis both as an active component and as a support. The oxidized and N-doped graphene nanoflakes (GNFs) of low domain size (10–30 nm) have been studied in present work as supports for cobalt-based Fischer-Tropsch catalysts. Three supports with different types of dominating nitrogen species were synthesized and the effect of both the nature and localization of nitrogen species in the support on the structure and performance of 10 wt.% Co catalysts was investigated. Varying the synthesis technique and post-synthesis treatment, the cobalt particle size and hence the activity of catalyst can be tuned. The catalysts supported on oxidized pristine and N-doped GNFs were found to be the most active. Transformations of N-groups during catalyst preparation and reduction were observed. In the case of edge localization of N-groups the cross-linking of support particles was detected that led to the diffusion hindering and low CO conversion over corresponding catalyst.

Carbon material (СAm), prepared on the basis of shadbush (Amelanchier) wood is used as a support of bismuth-promoted (0.6 wt %) Fe-containing catalyst of CO hydrogenation. Structural, morphological, and physicochemical characteristics of the systems are studied. It is established via IR spectroscopy that sub-carbonyl and bridge forms of absorption are observed when bismuth is present on a surface of Fe/СAm during calcination in a stream of CO. At the same time, only iron oxide particles form, substantially facilitating the process of catalyst reduction afterward.

General patterns of ozone pretreatment for subsequent fermentation into sugars are found, based on samples of different types of plant biomass. It is shown that the reactivity of plant substrates pretreated with ozone is determined by the amount of consumed ozone, and the rate of ozone consumption depends on the content of water in a sample. Optimum values of moisture (~2FSP) and ozone consumption (2–3 mol O3/C9PPU lignin) are found.

The dynamics of wheat straw delignification with ozone treatment is studied. The dependence of the residual lignin content on the specific absorption of ozone is determined. It is found that in a prolonged stage of ozonation, ozone is consumed mostly for the reaction with lignin. HPLC is used to record kinetic profiles of water-soluble products of ozonation. The IR spectra of straw samples with various degrees of delignification are analyzed. The results confirm the ozonolytic degradation of lignin and suggest that polysaccharides undergo partial oxidation during prolonged ozonation. A relationship is found between the lignin content and the reactivity of ozone-pretreated straw in enzymatic hydrolysis to sugars. The optimum consumption of ozone is 2 mol-equiv O3 per phenylpropane structural unit (PPU) of the lignin contained in the straw, which corresponds to a residual lignin content of ~10%.

The temperature dependence of the solubility product of copper (II) oxalate CuC2O4 was determined in the range 20–45 °C from the results of precipitation potentiometric titration of aqueous Cu2+ so...

Supercritical antisolvent (SAS) precipitation technique, although being versatile and ecologically friendly, suffers from the lack of convenient methods for necessary thermodynamic parameters measurement. Recently we have proposed a method for solubility measurement in binary fluids based on an online hyphenation of supercritical antisolvent method and supercritical fluid chromatography (SAS-SFC). In this paper, we demonstrate the applicability of this method to the investigation of both selective precipitation from solution and particle size tuning in SAS using lower dicarboxylic acids as model objects. Measured solubility values adequately reflect selective crystallization from solution. SAS precipitation was observed only for those components, which concentration was above solubility in CO2-solvent mixture as predicted by SAS-SFC method. Also, concentration dependences of particle size plotted in supersaturation coordinates instead of direct concentration in initial solution give additional insight into crystallization behaviour in SAS.

A new way of diffractometrically measuring the degree of crystallinity of substances by determining the rate of change in function I = f(2θ) over the range of scattering angles of a test sample’s diffractogram is used to study changes in the crystallinity of wheat straw during ozone treatment. It is shown that the crystallinity of a sample is inversely proportional to its content of lignin. No correlation is found between the crystallinity of the lignocellulosic substrate and its reactivity in the processes of enzymatic hydrolysis to sugars.

Cylindrical and conical carbon nanotubes were used as catalysts for the conversion of C3–C4 secondary aliphatic alcohols. The effect of the oxidative and reductive treatment of carbon nanotubes on the catalytic activity, selectivity and the conversion of propan-2-ol and butan-2-ol related to the structure of carbon matrix was revealed.

The aim of the research is to choose the most efficient adsorbent for two-stage ozone-sorption purification of groundwater containing both trichloroethylene (TCE) and tetrachloroethylene (PCE) betw...

The transformation of pinewood under the action of ozone is investigated via synchronous thermal analysis in combination with the mass spectral (MS) analysis of incondensable products of pyrolysis. TG/DTG and MS data are analyzed from the viewpoint of the conversion of wood lignin (LG), hemicelluloses (HCs), and cellulose (CL) in the composition of products of LG oxidation using different amounts of absorbed ozone. Results from TG/DTG analysis indicate the destruction of hemicelluloses during pinewood ozonation. The lower temperature of the thermal destruction of cellulose material (CM) produced from ozonized wood correlates with the lower LG content, the depolimerization of CL, and the formation of products of oxidation in biomass ozonation. Data from TG/DTG and MS analyses suggest that when wood is treated with ozone, aromatic lignin structures are not only destroyed but polymerized as well.

The effectiveness of ozone pretreatment of pine wood for subsequent fermentation in sugars is studied. Kinetic curves for the ozone consumption by the samples with different water contents were obtained, and the optimum wood moisture values are determined during ozonation (50–70 wt %). It is found that the yield of reducing sugars in the enzymatic reaction grows in proportion to the amount of absorbed ozone and reaches a maximum at an ozone consumption of around 3 mmol/g of biomass, which corresponds to 2 mol-equivalent of O3/C9PPU lignin contained in the initial material. Upon prolonged ozonation, the yield of sugars falls.

It is shown that the rate of oxidation of oxalic acid H2C2O4 during the ozonation of its solutions grows considerably if sodium chloride is added to the solution. Based on the kinetics of evolution of molecular chlorine during ozone treatment of solutions of H2C2O4 and NaCl, the mechanism of reaction of oxalic acid with chlorine is clarified, and the rate constant of this reaction is determined.

The effect the structural properties of a support, magnesium aluminum spinel, with different structural characteristics has on the physicochemical properties of Fe–K-containing catalysts for the hydrogenation of CO is studied. It is shown that hematite is the main phase in Fe-containing catalysts. A highly disperse distribution of iron oxide on the surface of the substrate is observed in case of a bimodal distribution of meso-pores. It is shown via IR spectroscopy that Fe2+ cations and metallic iron are the main sites of adsorption. The introduction of potassium reduces the surface concentration of clusters (including Fe2+) in different coordination environments. A rise in the contribution from the subcarbonyl forms of adsorption to the spectrum of the absorption bands and a drop in the amount of oxidized iron on the surfaces of metallic iron particles are observed.

Combustion heats of graphene nanoflakes (GNFs) of different thicknesses produced by chemical vapor deposition method were measured for the first time by differential scanning calorimetry (DSC) in the temperature range of 303–1273 K. They were found to be lower than that of graphite and increase nonlinearly from 18.8 ± 1.1 to 30.5 ± 1.4 kJ g−1 with decrease in the specific surface area of GNFs from 1730 to 770 m2 g−1. The heat capacity of GNFs was calculated to be higher than that of graphite. The energy diagram for the heat of GNF combustion was proposed based on the literature data and results of DSC, Raman spectroscopy and transmission electron microscopy study. The obtained results expand the scarce thermodynamic data available for graphene-based materials.

New composites based on nitrogen-doped carbon nanoparticles (N-CNT), the surfaces of which are coated with metallic cobalt nanoparticles, are obtained via spark plasma sintering (SPS). Their morphology, microstructure, phase composition, and electric conductivity are examined thoroughly. The compacting of Co-modified nanotubes under specified SPS conditions is shown to help retain nitrogen atoms in the carbon structure and substantially raise the conductivity of the initial material, from 450 S/m for N-CNT to ∼4000 S/m in the sintered samples.

Values of specific electric conductivity are determined for nitrogen-doped carbon nanotubes (N‑CNTs) and N-CNTs oxidized with 68 wt % HNO3. It is established that the electrical conductivity of the material falls considerably along with nitrogen content in the tubular structure of the N-CNTs and an increase in the number of oxygen-containing groups on their surfaces due to a rise in the concentration of defects in their structure. The electrical conductivity of all types of samples rises along with pressure.

The work is devoted to the development of hybrid materials for medical hyperthermy based on carbon nanotubes (CNTs) modified in their internal channels by perovskite-like manganites. It is shown that phases are formed in preliminarily opened channels of tubes from precursors: salts, manganese, strontium, calcium and lanthanum carbonates and oxides. High-resolution transmission electron microscopy reveals fine crystalline particles of complex oxide phases inside the CNTs, and reflections corresponding to the temperature of the solid-phase synthesis of manganites are found on the calorimetric dependences.

Present work demonstrates the differences between the structure and surface transformations of carbon nanotubes (CNTs) and graphene nanoflakes with small particle size (GNFs) under oxidation and N-doping using Raman spectra processing. Jellyfish-like GNFs are rather new material that differs from the commonly known graphene nanoflakes by rounded edges and small size of particles (

The results of studies of a complex chemical reaction of ozone with chloride ions in aqueous solution, in crystalline salts, and in aerosol are generalized and systematized; its kinetics and mechanism are discussed. The role of the reaction in various industries, in particular, in water treatment, and in natural processes is considered.

CTAB templated Ce0.8Zr0.2O2 (CZ), MnOx-Ce0.8Zr0.2O2 (Mn-CZ), CeO2 and MnOx oxide catalysts were prepared by precipitation and tested in CO oxidation. Manganese was added to CZ oxide at the precipitation stage (Mn-CZ) or by impregnation of the precipitated CZ oxide with manganese salt (Mn-CZ IM). Despite the decrease in the specific surface area after modification with Mn, both Mn-modified catalysts showed the significant improvement in the catalytic performance. Mn-CZ IM exhibited better catalytic activity than Mn-CZ, which was explained by the different distribution of manganese in CZ found by the complex SEM-EDS, XRD, TPR, Raman spectroscopy, XPS, and EPR study. In Mn-CZ both Mn2+ and Mn3+ ions are incorporated into the CZ lattice and form particles of MnOx phases uniformly distributed over the surface and in the bulk of CZ. In contrast, in Mn-CZ IM no manganese ions are embedded into the crystal lattice of CZ, while the surface of Mn-CZ IM comprises local areas mainly formed by CZ or MnOx. Such arrangement provides the additional adsorption sites and the second redox pair (Mn3+/Mn2+) in addition to Ce3+/Ce4+, improving low-temperature efficiency, whereas the surface areas depleted with MnOx serve as a source of the active oxygen from the CZ lattice, enhancing CO oxidation at high temperatures.

Doping of graphene-based nanomaterials with heteroatoms is a flexible and widely used approach to modify their electronic structure and chemical properties. Applications of these doped materials may imply thermal treatment, so this work was devoted to the transformations of nitrogen-containing functional groups during heating. Jellyfish-like few-layer graphene nanoflakes with the bulk and surface localization of N-groups were synthesized by different techniques: CVD growth, post-doping, CVD growth followed by oxidation, and nitric acid treatment. Synthesized materials contained a wide range of N-functionalities. The mechanism of their thermal transformations and decomposition was studied using XPS and TGA–MS. The activation energies for the decomposition of different nitrogen-containing groups were estimated by the Kissinger method.

The solubility and decomposition kinetics of ozone in pure water at different temperatures were studied. The Henry constant of ozone, kinetic order, and decomposition rate constant were determined. It was shown that to determine the concentration of dissolved ozone, it is sufficient to use the Henry law [O3] = $${{H}_{{{{{\text{O}}}_{{\text{3}}}}}}}$$ C(O3), where [O3] and C(O3) are the ozone concentrations in solution and gas phase (M), respectively; and the Henry constant is determined by the equality ln $${{H}_{{{{{\text{O}}}_{{\text{3}}}}}}}$$ = –(9.445 ± 1.00) + (2406 ± 300)/T (in the range 20–40°С). The dependence of the solubility on the kinetic characteristics of ozone decomposition and mass transfer, water purity, and reactor characteristics was discussed.

The electronic structure of mono- and binuclear platinum complexes with N-phenyl-o benzosemiquinondiimine ligands was studied using X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, and the density functional theory. The oxidation state of the central platinum ion corresponds to that of Pt(II). Upon the transition from the trans-complex 1 to the cis-complex 2 and to the binuclear complex 3, the electron density on platinum and nitrogen atoms decreases thus testifying the participation of platinum and nitrogen atoms in the oxidation processes and in the formation of binuclear complex 3.

The effect of concentrations of Cl– and H+ ions, temperature, and ionic strength on the rate constant of the reaction between O3 and Cl–(aq) is studied experimentally. The reaction proceeds according to a mechanism of oxygen transfer and results in the formation of molecular chlorine in acidic medium. A formula is proposed for calculating the dependence of the rate constant on these factors.

Compared with the planar two-dimensional (2D) all-solid-state thin film batteries (TFBs), three-dimensional (3D) all-solid-state TFBs with interdigitated contact between electrode and electrolyte possess great advantage in achieving both high energy and power densities. Herein, we report a facile fabrication of vertically aligned oxygen-deficient α-MoO3-x nanoflake arrays (3D MOx) using metal Mo target by direct current (DC) magnetron sputtering. By utilizing the 3D MOx cathode, amorphous lithium phosphorus oxynitride solid electrolyte, and lithium thin film anode, 3D solid-state TFBs have been successfully fabricated, exhibiting high specific capacity (266 mAh g−1 at 50 mA g−1), good rate performance (110 mAh g−1 at 1000 mA g−1), and excellent cycle performance (92.7% capacity retention after 1000 cycles) in comparison with the 2D TFBs using the planar MOx thin film as cathode. The superior electrochemical performance of the 3D TFBs can be attributed to the 3D architecture of the cathode, maximizing the cathode/electrolyte interface while retaining the short Li+ diffusion length. The charge/discharge measurements of the 3D MOx cathode in liquid electrolyte, however, exhibit fast capacity fading, demonstrating the advantage of using transition metal oxide as cathode in solid-state batteries. Keywords: Thin film batteries, All solid-state Li batteries, MoO3, Nanoflake arrays, 3D cathode

A simple and reliable way of determining the potential of a laboratory silver/silver chloride electrode (SSCE) is proposed, based on measuring the emf of a galvanic cell composed of silver/silver chloride and copper/copper sulfate (copper in a saturated aqueous solution of copper sulfate) electrodes. The standard thermodynamic characteristics of the reduction of a hexacyanoferrate(III) ion to hexacyanoferrate(II) in an aqueous solution are determined using the determined values of the SSCE potential.

The effective activation energies of CO methanation and water gas shift reactions in the Fischer–Tropsch process in the presence of cobalt catalysts supported on oxidized and unoxidized carbon nanotubes have been determined. It has been found that the energy of CO methanation does not depend on the oxidation degree of the support and varies in a narrow range from 135 to 153 kJ/mol, while the values of this parameter for the water gas shift reaction increase in the case of the oxidized support from 40 to 201 kJ/mol due to the change in the mechanism of the process.

In this work, we present a novel method for measuring solubility designed specifically for multi-component supercritical fluids. The method is based on an online hyphenation of supercritical antisolvent precipitation and subsequent supercritical fluid chromatography. A concentrated solution of a target substance in an organic solvent is contacted with supercritical CO2 or other fluid in a precipitation chamber which leads to partial precipitation of the compound. A small portion of the outlet stream is repeatedly injected into a supercritical fluid chromatography, and concentration measurement is performed using a pre-defined calibration. Solubility of aspirin as a model object in CO2-methanol, CO2-ethanol and CO2-acetone was measured using this method, results are in good agreement with available literary data. The method allows gaining several data points per day which is much faster than the majority of existing methods for solubility measurement in multi-component supercritical fluids.

Electrical conductivities of pure tetraalkylammonium- (N+Me4, N+Et4, N+Bu4, N+Me3Hex) and imidazolium- (EMIM+, BMIM+) based ionic liquids (ILs) with bis(trifluoromethylsulfonyl)imide (TFSI−) anion and their acetonitrile solutions were measured in two temperature ranges of 298–368 and 298–348 K. Acetonitrile was used as an organic solvent to decrease the viscosity of ILs and, therefore, to increase the mobility of charge carriers. The maximum conductivity of acetonitrile solutions of both tetraalkylammonium- and imidazolium-based ILs was found to decrease with cation size. The conductivity – temperature dependencies of pure ILs and their acetonitrile solutions were analyzed using three approaches based on the Arrhenius equation for non-associating electrolytes, the Vogel-Fulcher-Tammann equation for ionic conductivity of glass-forming liquids and the Litovitz equation for associated liquids. The dilution of ILs with acetonitrile significantly reduced their activation energies of conductivity. At the same time, the activation energy decreased with increasing the alkyl chain length because of the deceleration of the ion transfer and the growth of the viscosity.

Adsorption of model polar (water) and non-polar (n-hexane) compounds on the surface of oxidized and non-oxidized carbon nanotube (CNT) supports at different stages of Co/CNT catalyst preparation has been studied to reveal the influence of the surface functionalization of the CNT support on the catalyst selectivity in Fischer-Tropsch synthesis (FTS). Dynamic vapor sorption experiments showed that defunctionalization of the surface of the CNT support during catalyst annealing and reduction led to its hydrophobization and, as a result, no noticeable difference was observed between the adsorption properties of the oxidized and non-oxidized supports towards water and hydrocarbons. Therefore, oxidation of the CNT support does not significantly affect the adsorption properties of the supported catalyst and it is not a crucial factor for the catalyst selectivity in FTS.

The consumption of ozone by pine wood with a water content of 7 to 85% is investigated. The specific ozone consumption and degree of ozone conversion during the ozonation of wood with different contents of water are determined. IR absorption spectra of ozonated lignocellulosic material (LCM) produced from wood are analyzed. Destruction of the lignin aromatic structure and the formation of carbonyl- and carboxyl-containing compounds are observed. The content of cellulose in a sample of ozonated LCM grows along with the specific ozone consumption. Products of the ozonolysis of lignin (glyoxylic, formic, and oxalic acids) form during ozonation of the wood, as determined via HPLC. It is shown that the oxidation of acids by ozone proceeds in the water phase of the sample. Based on the data for the destruction of lignin and the results from investigating the process of wood ozonation, it is concluded that the optimum content of water for wood treatment is 60–63%. It was shown that the destruction of lignin during wood ozonation proceeds via ozonolysis and with the participation of radicals formed in the reaction between ozone and water.

The acid dissociation constants (Ka) of HCl, HBr, and HI are determined using the equation $${{K}_{{\text{a}}}} = K_{{\text{a}}}^{'}f_{{{\text{HA}}}}^{\infty }$$ , where $$K_{{\text{a}}}^{'}$$ is the apparent dissociation constant and $$f_{{{\text{HA}}}}^{\infty }$$ is the activity coefficient of an undissociated molecule in an infinitely dilute aqueous solution. Apparent dissociation constants $$K_{{\text{a}}}^{'}$$ are calculated using reliable reference data. Limiting activity coefficients $$f_{{{\text{HA}}}}^{\infty }$$ are calculated using the COSMO-RS approach. The validity of the results is confirmed by comparing them and the known $$f_{{{\text{HA}}}}^{\infty }$$ values for similar compounds.

Using the methods of scanning and transmission electron microscopy (SEM and TEM), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy, the influence of concentration, time, and the procedure for the oxidative treatment of the surface of carbon nanotubes (CNTs) and nitrogen-doped carbon nanotubes (N-CNTs) in the mixture with calcium nitrate was studied. All prepared materials were tested as supports of cobalt-supported catalysts in the Fischer–Tropsch process. It is shown that an increase in the Ca(NO3)2 concentration from 15 to 25 wt % leads to the destruction of CNTs, and the time of treatment and oxygen concentration in the oxidizing mixture have almost no effect on the morphology and physicochemical characteristics of the materials. It is found that heterosubstitution in nanotubes and a change in the surface relief of the carbon support lead to an increase in CO conversion, and the catalyst activity increases in the series: Co/CNTs → Co/N-CNTs → Co/CNTs(Ca) → Co/N-CNTs(Ca).

Porous oxide materials are widely used in environmental catalysis owing to their outstanding properties such as high specific surface area, enhanced mass transport and diffusion, and accessibility of active sites. Oxides of metals with variable oxidation state such as ceria and double oxides based on ceria also provide high oxygen storage capacity which is important in a huge number of oxidation processes. The outstanding progress in the development of hierarchically organized porous oxide catalysts relates to the use of template synthetic methods. Single and mixed oxides with enhanced porous structure can serve both as supports for the catalysts of different nature and active components for catalytic oxidation of volatile organic compounds, soot particles and other environmentally dangerous components of exhaust gases, in hydrocarbons reforming, water gas shift reaction and photocatalytic transformations. This review highlights the recent progress in synthetic strategies using different types of templates (artificial and biological, hard and soft), including combined ones, in the preparation of single and mixed oxide catalysts based on ceria, and provides examples of their application in the main areas of environmental catalysis.

Dicationic ionic liquid (IL) dibutyltetramethylethylenediammonium tetrafluoridoborate was synthesized for the first time by quaternization followed by ion exchange. The chemical composition was confirmed by 1H, 19F, and 13C nuclear magnetic resonance (NMR) spectroscopy. The crystal structure of the IL under discussion was determined from single crystal diffraction and can be described in monoclinic syngony with P21/c space group. Using thermal analysis and mass spectrometry, thermal stability of this IL as well as possible directions of its destruction was analyzed. Melting point for this liquid was determined by simultaneous thermal analysis as 135 °C. The electrochemical stability range for this ionic liquid was find to be nearly symmetrical accordingly to cyclic voltammetry and estimated as 3.75 V.

A study was made of the applicability of supercritical antisolvent precipitation to producing microparticles of the antiasthmatic drug salbutamol sulfate that are suitable for manufacturing the drug in inhalation dosage form. Depending on the salbutamol concentration in the initial solution, the flow rate of the solution, and pressure, either spherical or needle-like particles 0.7–8.5 μm in size form. The dependence of the average particle size on the salbutamol concentration in the initial solution is nonmonotonic. The conditions were determined under which the obtained salbutamol particles meet the shape and size requirements for fabrication of inhalation dosage forms.

The influence of a set of additives of various nature on the separation of salbutamol sulfate enantiomers by supercritical fluid chromatography on the stationary phase based on amylose tris(3-chloro-5-methylphenylcarbamate) is considered. The application of water and acidic additives does not lead to enantioseparation. The use of hexafluoroisopropyl alcohol as an additive allows separation to occur but leads to a strong distortion of the chromatographic peaks. The application of basic additives such as isopropylamine or ammonia provides a stable separation with high selectivity and resolution as well as with the symmetrical peak shape. The selectivity coefficient is surprisingly almost independent of the amine modifier concentration in the mobile phase.

Solubility of ozone and kinetics of its decomposition in aqueous solutions of NaCl and NaCl + HCl have been investigated as functions of solution composition, electrolyte concentration, and tempera...

Herein, ZnS nanoparticles on Nitrogen (N) and Sulphur (S) co-doped carbon nanosheets (ZnS@NSC) are prepared through a highly efficient sol-gel synthesis. Interestingly, the ZnS nanoparticles are encapsulated in ultrathin carbon shells, which are crucial to buffer the volume changes of ZnS during sodium ion intercalation/de-intercalation. Meanwhile, the nanosheets and ultrafine carbon shells together constitute the N, S co-doped carbon framework, which not only can give rise to abundant active sites for sodium storage but also greatly enhance the electrical conductivity. As a result, the ZnS@NSC achieves a reversible capacity of 734 mAh g−1 at 0.5 A g−1 and excellent cycling stability (73.6% capacity retention after 380 cycles at 0.5 A g−1).

The absorption of ozone by aspen wood with moisture contents of 45, 55, and 70% is studied. Time dependencies are obtained for the specific absorption of ozone, the degree of ozone conversion, and the content of the products of oxidation. It is shown that the resulting compounds are products of the oxidative degradation of lignin, and that the efficiency of delignification is greatest for wood with a moisture content of 55%. Water-soluble products are analyzed via HPLC, revealing the presence of oxalic, formic, and glyoxylic acids in contact solutions. Based on the dependence of the content of acids on the specific consumption of ozone, it is concluded that the acids are oxidized by ozone. The inhibiting role of the reactions between ozone and water-dissolved products of the substrate oxidation is noted.

A comparative study of the sorption properties of lignocellulosic plant materials (aspen and pine wood and wheat straw) is performed using the cationic dye methylene blue (MB). Experimental data on the adsorption of MB from water solutions are described by the Langmuir model. It is established that the isotherms of MB adsorption on softwood and hardwood samples are almost the same and the maximum sorption capacity is 26.4 ± 0.7 mg/g. The amount of MB adsorbed by wheat samples at the same equilibrium concentrations is greater and reaches a maximum of ~46 mg/g. The estimated specific surface area accessible to dye molecules is 52 m2/g for the wood and 91 m2/g for the straw. It is shown that the ozonation of aspen wood reduces the affinity of the adsorbent surface toward MB but has no effect on its adsorption capacity.

3D frameworks of carbon nanotubes (CNTs) uniformly decorated by cobalt oxide or carbon-encapsulated cobalt nanoparticles were obtained by spark plasma sintering for the first time. The influence of the sintering temperature (TS) and Co content on the morphology, structure, and electrical and magnetic properties of the obtained materials was investigated by Raman spectroscopy, electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and in situ magnetometry. It was shown that application of the SPS technique allowed simultaneous compaction of the material, formation of CNT framework, and Co oxide reduction. The appearance of the carbon shell around 4–10 nm Co particles was observed at TS > 600 °C. At higher TS, the Co particle size increased (up to 300 nm at 1400 °C), whereas the carbon shell ordered and thickened. The formation of large-size few-layers graphene sheets was observed at TS = 1400 °C. Electrical conductivity of the composites was found to be higher than that of sintered prist...

Results are presented from studying collagen degradation in scleral and corneal tissues upon CW IR laser irradiation at a wavelength of 1.56 μm and powers of 1.4 and 7 W. The exposure time is such that the radiometrically determined maximum tissue temperature ranges from 55 to 70°C. It is shown that at a power of 1.4 W, laser-induced collagen denaturation in sclera and cornea starts at 55 and 60°C, respectively. When the power is increased to 7 W, the temperature of denaturation onset rises by 2°C. These findings are discussed from the viewpoint of the joint photothermal and photomechanical effects of laser irradiation.

The hydrogenation of anthracene on a heterogeneous catalyst containing 3 wt % Pt/C (Aldrich) at 215, 245, and 280°C and the pressures of 40 and 90 atm is studied. The hydrogenation of anthracene to a completely hydrogenated product is considered in detail. The final product (perhydroanthracene) consists of five conformational isomers with total selectivity of more than 99%. The ratio of perhydroanthracene isomers in the end product is shown to be determined by the conditions (P, T) of hydrogenation. The rate of hydrogenation is found to slow upon an increase in the degree of benzene ring saturation. A mixture of perhydroanthracene isomers is dehydrogenated in an autoclave at 260−325°C on 3 wt % Pt/C catalyst (Aldrich) and in a flow reactor at 300–360°C on 3 wt% Pt/Sibunit catalyst. The reactivity of perhydroanthracene isomers in dehydrogenation is shown to differ.

The effect the means of synthesis have on the texture, phase composition, redox properties, and catalytic activity of binary oxide systems with the composition Ce0.5Zr0.5O2 are studied. The obtained samples are characterized via BET, SEM, DTA, XRD, and Raman spectroscopy. A comparative analysis is performed of the physicochemical properties of biomorphic systems Ce0.5Zr0.5O2 obtained using wood sawdust and cellulose as templates and the properties of binary oxides of the same composition obtained by template-free means. The catalytic properties of the obtained oxide systems Ce0.5Zr0.5O2 are studied in the reaction of carbon black oxidation. It is shown that the texture of the oxide depends on the means of synthesis. When biotemplates are used, fragile porous systems form from thin binary oxide plates containing micro-, meso-, and macropores. Oxide obtained via coprecipitation consists of dense agglomerates with pores around 30 A in size. In supercritical water, nanoparticles of metal oxide form that are loosely agglomerated. The intermediate spaces between them act as pores more than 100 A in size. A system of single-phase pseudocubic modification is obtained using a cellulose template. The crystal lattices of all the obtained systems contain a great many defects. It is shown that the system prepared via synthesis in supercritical water has the best oxygen-exchange properties. A comparative analysis is performed of the effect the physicochemical properties of the samples have on their activity in the catalytic oxidation of carbon black.

The bioconversion of phenolic monomers of lignin (veratrol, vanillin, and vanillyl alcohol), hydrolyzed lignin, and sodium lignosulfonate (a product of the chemical modification of native lignin) by the basidiomycete Lentinus tigrinus was studied. It was found that the growth of the fungi on lignin monomer compounds is suppressed. A noticeable growth of the fungal biomass was observed only on the technical substrate sodium lignosulfonate. A comprehensive physicochemical study of the products of microbial transformation of sodium lignosulfonate was performed. It was established that the main direction of lignin bioconversion is oxidative condensation to form humic substances. In this case, depolymerization of the phenolic skeleton of lignin to monomeric phenol derivatives did not occur. The aromatic carbon atoms of the phenolic skeleton, unlike the carbon atoms of polysaccharides, were not involved in the fungal biomass growth. The observed growth of the fungus on the technical substrate sodium lignosulfonate can be explained by the presence of admixtures of oligomeric polysaccharides hemicellulose and cellulose, which can be used by the fungus as a carbon source.