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Due to the limited volumes of conventional sources of cellulose (cotton and wood), research centered on producing the most competitive science-driven products – cellulose nitrates – from new, domestic, easily renewable feedstocks is extremely relevant. The review of scientific literature corroborates the lack of data on the feasibility to obtain cellulose nitrates from Miscanthus, except for the authors’ publications. Here we suggest a tree-like industrial crop, Miscanthus var. KAMIS, growing with an yield of up to 20 t/ha a year on industrial plantations in Kaliningradskaya, Kaluzhskaya and Yaroslavskaya Oblasts and in Primorskiy Krai. A pulp sample derived from Miscanthus var. KAMIS by the nitric-acid process exhibits a high α-cellulose content of 96 % and degree of polymerization of 1350. Under optimum synthesis conditions previously identified for unconventional feedstocks, a cellulose nitrate sample was synthesized by treating the pulp with commercially available mixed acid and had the following functional characteristics: 11.26 % nitrogen content, 52 mPа∙s viscosity, and – 95 % solubility on alcohol-ester mixture. Morphological features of pulp and cellulose nitrate samples were characterized by scanning electron microscopy. IR spectroscopy revealed the presence of functional groups in pulp samples (3411, 2913, 1637, 1429, 1369, 1317, 1161, 700-500 cm-1) and cellulose nitrate samples (2553, 1642, 1276, 830, 746, 680 cm-1), which allow those samples to be identified as cellulose and nitrate cellulose esters, respectively. It was found by scanning electron microscopy that the cellulose nitrate sample matches industrial Colloxylines by the onset temperature of decomposition (199 °С) and specific head of decomposition (8,43 kJ/g). The practical importance of this study is that we experimentally justify the feasibility to utilize the new, unconventional, domestic, easily renewable feedstock, Miscanthus var. KAMIS, as a precursor of high-quality cellulose nitrates

The compositions of alumoboro- and alumochromophosphate with a tetratomic alcohol, pentaerythritol, which is the component forming hydrogen and chemical bonds with the phosphate groups, are considered. The extremum dependence of the softening point on the concentration of pentaerythritol accompanied by a symbatic change in the moisture resistance is found. The heat and thermal resistance, oxygen index of the cured compositions, and bending strength of the composites reinforced by a basalt fabric are measured. The energy of the intermolecular bonds of the monomeric phosphate units with pentaerythritol is calculated, and computer modeling of the conformation of the complexes is performed. The higher chemical activity of alumochromophosphate in comparison with alumoborophosphate is determined.

The interaction energies of fragments of aluminoborophosphate chains with water molecules and nitrogen-containing compounds are calculated using a density functional theory (DFT). The conformational changes of monomer units of aluminophosphate and molecular complexes during the formation of hydrogen bonds are analyzed. The complexation of aluminoborophosphate with various nitrogen-containing compounds, which leads to the displacement of water from the chain surface, is considered, and the thermal effects of complex formation are calculated. The moisture absorption of mixtures of oligomeric aluminoborophosphate with amines was measured upon various ratios of components.

The reactions of oligomeric aluminoborophosphates with hexamethylenediamine and pentylamine are studied, as are the properties of the obtained products which are polycomplexes with the participation of hydrogen bonds, which is confirmed by the results of quantum chemical calculations. The changes in the relaxation properties of the polycomplexes are determined by the softening and flow temperatures measured by thermomechanical analysis. It is shown that the modification of polyphosphates by primary amines under mild conditions leads to an increase in the water resistance of the obtained polycomplexes.

The possibility of synthesizing and processing incombustible materials based on oligomer and polymer oxides and their hybrids with organic and organoelement compounds at temperatures of 20–200°C is explored. Inorganic thermosetting plastics with a wide range of pour points (100–700°C) are synthesized. A more intense heat treatment can provide the formation of fireproof materials. Cast polymer–polymer blends of inorganic/organic polymers prepared by melt blending are studied. Possible areas of application of reinforced materials based on inorganic and hybrid impregnation composites are determined.

The synthesis of the porphyrin-calix[4]arene conjugates was carried out using the Pd(0)-catalyzed amination of Zn(II) meso-(3-bromophenyl)porphyrinate with bis(3-aminopropoxy)substituted calix[4]arenes (in cone and 1,3-alternate conformations). One of the conjugates was demetalated to give free porphyrin base derivative. The investigation of the fluorescence of the conjugates was studied in the presence of 18 metal perchlorates. The zinc porphyrinate derivatives were found to quench fluorescence in the presence of Cu(II), Al(III) and Cr(III) cations as well as on protonation. Metal-free conjugate was shown to act as a molecular probe for Zn(II), Cu(II) and Cd(II) cations due to strong and different changes of the emission caused by these metals.

The conceptual possibility to synthesize bacterial cellulose nitrates with the use of commercial mixed acid was demonstrated. The initial bacterial cellulose was produced by the Medusomyces gisevii Sa-12 symbiotic culture in a synthetic nutrient broth in a Binder constant climate chamber. The resulting bacterial cellulose nitrate sample had 11.45% nitrogen content, 1900 cP viscosity, 15.8% solubility in ethanol—diethyl ether mixture, and 0.10% ash content. An extremely high sample viscosity (organogelation) in a ∼2% solution in acetone was observed.

Bacterial nanocellulose, which was produced by Medusomyces gisevii Sa-12 cultured in enzymatic hydrolysates of Miscanthus, was studied by X-ray diffraction. The characteristics of the supramolecular structure of the crystalline component of cellulose samples, such as the degree of crystallinity and the size and shape of elementary fibrils, were determined. The atomic structure was compared with the known structural models of cellulose, and the synthesized bacterial nanocellulose was shown to be cellulose Iα. The lengths and angles of the triclinic unit cell were determined. The composition of the culture medium made from enzymatic hydrolysates of Miscanthus was found to have an effect on the shape and size of elementary fibrils and have no effect on the degree of crystallinity and the fraction of cellulose allomorph Іα. The use of Medusomyces gisevii Sa-12 as the producing organism allows the preparation of bacterial nanocellulose with a high degree of crystallinity in the range of 86–93% containing cellulose allomorph Іα as the major component.

Here we provide a scientific justification and experimental support for the choice of easily renewable cellulosic feedstock Miscanthus sacchariflorus (Maxim.) Hack. in order to obtain high-quality nutrient broths therefrom for bacterial cellulose biosynthesis. The plant life-forms promising for breeding were screened under introduction conditions at the Central Siberian Botanical Garden, SB RAS, and this study was thus aimed at investigating the full and reduced ontogenetic patterns; cellulose and noncellulosic contents, including lignin; and duraminization of vegetative (feedstock source) organs throughout the seasonal development. The full ontogenetic patterns of the plants grown from seeds that had been collected in native habitats were compared to show that M. sacchariflorus and M. sinensis Anderss. accessions are distinguished by longer being at the most vulnerable developmental stages: seedlings and plantlets. Hence, it is preferable to cultivate seedlings on protected ground, and plantations are advisable to establish with more stable cloned vegetative material. The chemical compositions of the whole plant, leaf and stem separately, from seven M. sacchariflorus harvests were examined to reveal a rise in cellulose content and a drop in noncellulosic content with plantation age. The Miscanthus stem was found to contain more cellulose than the leaf, regardless of the plant age. The overall cellulose content was 48−53 %, providing a rationale for studies of bacterial cellulose biosynthesis in a M. sacchariflorusderived nutrient medium. Since high lignin content is undesirable for technological processes concerned with biosynthesis of bacterial cellulose, we performed histochemical assays of transverse sections of the culms to monitor the seasonal course of lignification. Our results suggest that the specific time limits for harvesting the aboveground biomass as a feedstock be validated by histochemical data on the seasonal course of lignification of M. sacchariflorus sprouts. To sum up, the examined chemical composition of M. sacchariflorus grown in the Siberian climate conditions demonstrated its prospects as a source of glucose substrate, the basic component of good-quality nutrient media for biosynthesis of bacterial cellulose.

Cellulose nitrates corresponding in the basic properties to high-viscosity lacquer-grade colloxylin were prepared by esterification of cellulose pulp, isolated from domestic rapidly renewable feedstock—agroindustrial waste—oat hulls, or cotton cellulose with a sulfuric and nitric acid mixture. The experimental samples of cellulose nitrates were comparatively evaluated. The IR and 13С NMR spectroscopy data confirmed the identity of chemical structure. High chemical purity of samples was confirmed by differential scanning calorimetry and ampule chromatography procedure. The cellulose nitrate samples have satisfactory mechanical sensitivity level: the lower limit of impact sensitivity is 50 mm and that of friction sensitivity is 1200 kgf/cm2; they have good chemical compatibility and high chemical stability when blended with plasticizers. The obtained results attest to expediency of using cellulose nitrates from oat hulls as a component of explosive compositions.

Extended cultivation with multiple removal of BC pellicles is proposed herein as a new biosynthetic process for bacterial cellulose (BC). This method enhances the BC surface area by 5–11 times per unit volume of the growth medium, improving the economic efficiency of biosynthesis. The resultant BC gel-films were thin, transparent, and congruent. The degree of polymerization (DP) and elastic modulus (EM) depended on the number of BC pellicle removals, vessel shape, and volume. The quality of BC from removals II–III to VII was better than from removal I. The process scale-up of 1:40 by volume increased DP by 1.5 times and EM by 5 times. A fact was established that the symbiotic Medusomyces gisevii Sa-12 was adaptable to exhausted growth medium: the medium was able to biosynthesize BC for 60 days, while glucose ran low at 24 days. On extended cultivation, DP and EM were found to decline by 39–64% and 57–65%, respectively. The BC gel-films obtained upon removals I–VI were successfully trialed in experimental tension-free hernioplasty.

Bacterial nanocellulose (BNC) is a unique product of microbiological synthesis, having a lot of applications among which the most important is biomedicine. Objective complexities in scaling up the biosynthesis of BNC are associated with the nature of microbial producers for which BNC is not the target metabolite, therefore biosynthesis lasts long, with the BNC yield being small. Thus, the BNC scale-up problem has not yet been overcome. Here we performed biosynthesis of three scaled sheets of BNC (each having a surface area of 29,400 cm2, a container volume of 441 L, and a nutrient medium volume of 260 L and characterized them. The static biosynthesis of BNC in a semisynthetic nutrient medium was scaled up using the Medusomyces gisevii Sa-12 symbiotic culture. The experiment was run in duplicate. The BNC pellicle was removed once from the nutrient medium in the first experiment and twice in the second experiment, in which case the inoculum and glucose were not additionally added to the medium. The resultant BNC sheets were characterized by scanning electron microscopy, capillary viscosimetry, infrared spectroscopy, thermomechanical and thermogravimetric analyses. When the nutrient medium was scaled up from 0.1 to 260 L, the elastic modulus of BNC samples increased tenfold and the degree of polymerization 2.5-fold. Besides, we demonstrated that scaled BNC sheets could be removed at least twice from one volume of the nutrient medium, with the yield and quality of BNC remaining the same. Consequently, the world’s largest BNC sheets 210 cm long and 140 cm wide, having a surface area of 29,400 cm2 each (weighing 16.24 to 17.04 kg), have been obtained in which an adult with burns or vast wounds can easily be wrapped. The resultant sheets exhibit a typical architecture of cellulosic fibers that form a spatial 3D structure which refers to individual and extremely important characteristics of BNC. Here we thus demonstrated the scale-up of biosynthesis of BNC with improved properties, and this result was achieved by using the symbiotic culture.

We present a scheme for an integrated four-wave mixing source of narrow-band path-entangled photon pairs with efficient spatial pump self-rejection. The scheme is based on correlated loss in a system of waveguides in Kerr nonlinear media. We demonstrate that this setup allows for upwards of 100dB pump rejection, without additional filtering. The effect is reached by driving the symmetric collective mode that is strongly attenuated by an engineered dissipation, while photon pairs are born in the antisymmetric mode. A similar set-up can additionally be realized for generation of two-photon NOON states, also with pump self-rejection. We discuss implementation of the scheme by means of the coherent diffusive photonics, and demostrate its feasibility both in glass (such as fused silica-glass and IG2), and planar semiconductor waveguide structures in indium phosphide (InP) and in silicon., 12 pages, 6 figures

Bacterial cellulose (BC) was synthesized from biomass of Miscanthus grown in West Siberia. Miscanthus biomass was pretreated at atmospheric pressure with 4 wt.% solutions of HNO3 and NaOH in one and two stages. The effect of four methods of the pretreatment of the feedstock on BC yield and properties was examined. The resultant pulps were subjected to enzymatic hydrolysis with commercial CelloLux-A and BrewZyme BGX enzymes. Biosynthesis of BC was run under static and non-sterile conditions using Medusomyces gisevii Sa-12. The two-stage pretreatment of Miscanthus biomass gave a 20 % increase in BC production compared to the single-stage pretreatment. The resultant BC exhibited a high crystallinity index (88–93 %) and an extraordinarily high content of allomorph Iα (99–100 %), irrespective of the pretreatment method; therefore, it has been revealed for the first time that the Medusomyces gisevii Sa-12 symbiotic culture is capable of self-standardization against the quality of produced BC.

Products are obtained from interaction between oligomeric aluminoborophosphate (ABP) and aniline, both complexes based on hydrogen bonds, as confirmed with IR spectroscopy and quantum chemical calculations. Nitrogen and hydrogen atoms of an amino group in aniline form hydrogen bonds with hydrogen and oxygen atoms of a phosphate group in ABP, respectively, with a total energy of 14.2 kcal/mol. Aniline, when added to ABP surrounded with a shell of water molecules, displaces two water molecules from the surface of the chain. The energy gain is 9.1 kcal/mol. IR spectroscopy data show that there are strong donor-acceptor interactions between water molecules and aluminum and phosphorus atoms of ABP in the solid-state polycomplex sample. The thermoplastic oligomeric complexes leads to an increase in the softening temperature and fluidity with an increase in an amount of aniline. This means that polyoxide inorganic polymer (metal phosphate) is possible to be modified with a monofunctional amine under “mild” conditions. We showed that the water resistance of the polycomplex is greater than that of ABP.

A technology has been developed for the synthesis of bacterial nanocellulose from oat hulls and Miscanthus. The Мedusomyces gisevii Sa-12 microbial producer was found to synthesize bacterial nanocellulose of high quality, regardless of the feedstock type and pretreatment method thereof.

The effect of culture conditions on the bacterial cellulose (BC) yield synthesized by symbiotic culture Medusomyces gisevii Sa-12 grown in synthetic nutrient medium was studied for the first time. The conditions providing the maximum yield of bacterial cellulose were evaluated: the initial glucose concentration in the culture medium was 20–25 g/L, the temperature was 24–27°C, the ratio of the nutrient medium to the air volume was 1: 10, and the content of the black tea extracts comprised 1.6–4.8 g/L. A sample of chemically pure BC with the following characteristics was obtained under the selected culture conditions: moisture— 99.0%, degree of polymerization—4800, average width of microfibrillar ribbons—30.6 nm, degree of crystallinity— 86%, and the content of triclinic modification Iα—98%.

Complete cycle of ethylene production from oat hulls as widespread agricultural waste was studied on a pilot scale. The cycle involved mechano-chemical, biotechnological and catalytic units. The oat hulls were pretreated with a 2%(w/w) sodium hydroxide solution in a setup consisting of a rotary-pulsating apparatus and a 100-L vessel to produce a pulp containing 90.3% of hydrolyzables. Simultaneous saccharification and fermentation of oat hull pulp with delayed inoculation (dSSF) into ethanol using commercial enzymes CelloLux-A and BrewZyme-BGX and non-GMO yeast Saccharomyces cerevisiae was carried out in 63-L reactor . At a solid loading of 33.3 g/L, the yield of reducing sugars was 97.9% on overall hydrolyzables basis. The ethanol yield during dSSF at a solid loading of 60 g/L was as high as 95 g ethanol/kg oat hulls. The produced raw-ethanol sample contained low impurities of methanol, propanol and alkali metals. The rectified ethanol samples were used for dehydration to ethylene with the overall production index as high as 38–51 g ethylene/kg oats hulls. A negative impact of the propanol and alkali metals impurities in the rectified ethanol on conversion and selectivity to ethylene were observed. Being purified from organic impurities, ethanol was dehydrated with higher conversion and selectivity to ethylene. When the ethanol samples that contain less than 0.02 g/L organic and no sodium impurities were used in ethanol dehydration process, the yield of ethylene was as high as 56 g ethylene/kg oats hulls. In this work, 12 kg of oat hulls was converted to 1.21 kg 94%(w/w) ethanol, which was then converted to 0.62 kg 99.5% ethylene; this is the first experimental study devoted to the production of ethylene from oat hulls on a pilot scale.

Oat hulls are a promising feedstock annually renewable at an industrial scale for the production of second generation ethanol. Chemical pretreatment of oat hulls with a 4% (w/w) nitric acid solution at atmospheric pressure was performed in pilot production to give a pulp in which hydrolyzables account for 79.9%. Acid-insoluble lignin totaling 12.5% in the pulp does not deteriorate the efficiency of enzymatic hydrolysis using an enzyme cocktail of commercial BrewZyme BGX and CelloLux-A. At an initial solid loading of 33.3 g/L, a hydrolyzate was obtained with a reducing sugar yield of 93.0% of the overall hydrolyzables. The high yield is assured only by removal of residual, water-soluble, nitrated lignin by water washing. Alcoholic fermentation was run using Saccharomyces сerevisiae Y-1693. Simultaneous saccharification and fermentation with delayed inoculation (dSSF) at an initial pulp loading of 90 g/L was found to improve the ethanol yield by 1.2 times compared to separate hydrolysis and fermentation (SHF), i.e. 0.428 versus 0.343 g/g cellulose, respectively. The ethanol samples obtained from oat hulls contain low percentages of esters and methanol.

The possibility of forming supramolecular structures of a polymer complex consisting of products of polycondensation of boric acid and imidazole from aqueous solutions and melts of the components is shown. Depending on the ratio of the components, the heat resistance of the polymer complex lies within 60 and 480°C. The effect of sharp decrease in the heat resistance of the complex and the degree of polycondensation of boric acid upon a slight increase in the imidazole concentration above the stoichiometric ratio is revealed, which was explained by the “blocking” of hydroxyl groups by imidazole molecules and, correspondingly, by a significant decrease in their chemical activity. The energies of the intermolecular bonds in the complexes are calculated.

The full cycle of bioethanol production from pretreated oat hulls is scaled for a pilot plant. The one-stage pretreatment of oat hulls with a dilute nitric acid at atmospheric pressure is scaled for a 250-L reactor. The total amount of hydrolysable polysaccharides in the resulting substrate is 87.2%. Using the commercially available enzyme preparations CelloLux-A and BrewZyme BGX and the industrial strain BKPM Y-1693 of Saccharomyces cerevisiae yeast, the process of enzymatic hydrolysis and alcoholic fermentation is successfully scaled for a 63-L reactor. The scaling factor is 1: 400. Bioethanol is obtained with a high yield of 17.9 daL/t. After rectification, the test sample of bioethanol meets the standards for high-purity alcohol from food raw materials according to the mass concentration of aldehydes, esters, and by the content of methanol.

An extreme dependence of the softening temperature of polycomplexes of p-phenylenediamine and low-molecular-weight polycondensation products of boric acid on the ratio thereof is revealed. The stoichiometric ratio of the BA/p-PDA complex is 75/25 wt %, which corresponds to a molar ratio of BA trimer/p-PDA = 1: 1. At a higher content of the amine, the softening temperature of the polycomplex decreases sharply, from 250 to 60°C, which is explained by the complexation of boric acid with the amine, a factor that prevents its dehydration. The energies of the intermolecular interaction between the components of the complex in a vacuum are calculated, and quantum-chemical calculations of the energy of interaction between the components of the complex are performed. The resulting products exhibit paramagnetic and fluorescent properties.

The photodissociation process of the nitrosyl hematoporphyrin complex has been studied using quantum-chemical methods. Photolysis of hematoporphyrin complexes is of high biological usefulness and is widely employed in laser-therapy methods. However, the mechanism of photodissociation of these complexes is not entirely clear. Based on the computations, we propose a detailed mechanism for the photolysis of the nitrosyl hematoporphyrin complex. A transition “dissociative” excited state has been described, which has an energy barrier value of only 0.4 eV for NO dissociation.

The results of studying the synthesis of cellulose nitrates from oilseed production residues (intermediate flax straw) and subsequent autoclaving of the obtained ethers are presented for the first time. Cellulose was isolated by the dilute nitric acid method, and cellulose nitrates were synthesized using an industrial sulfuric—nitric acid mixture. The resultant sample was autoclaved in three different modes. It was found that cellulose nitrates with the following properties can be obtained from the intermediate flax straw: weight fraction of nitrogen 12.23–12.34%, viscosity 2.7–16.0 cP, and solubility in an alcohol—ether mixture 95–96%. A similarity of the obtained cellulose nitrates and linter Colloxylin was shown by IR spectroscopy. The results of thermogravimetric analysis (TG) and 13C NMR spectroscopy for cellulose nitrates obtained from intermediate flax straw are presented.

The enzymatic hydrolysis of lignocellulosic materials (LCMs) from miscanthus and oat husks (OH) in an aqueous medium and the subsequent production of ethanol are studied. LCMs are obtained at a pilot plant of the Institute of Problems of Chemical and Energy Technologies by means of one-stage nitric acid treatment. Enzymatic hydrolysis is conducted in an aqueous medium with a high initial concentration of phosphates (90 g/L) using freely available CelloLux-A and BrewZyme BGX industrial enzymatic preparations. The yields of reducing compounds are found to be 65.4 and 73.3% for miscanthus and oat husk LCM, respectively. The composition of monosaccharides (products of enzymatic LCM destruction) is studied for the first time. It is shown that glucose comprises the largest share of monosaccharides. Ethanol is produced from LCM for the first time. Ethanol yields per metric ton of raw material are 19.4 and 16.2 daL/t for miscanthus biomass and OH, respectively. Ethanol samples are characterized by low methanol contents (0.002 to 0.005 vol %).

The complete production cycle of bacterial cellulose (BC) was studied on a pilot scale. Oat hulls, a globally abundant agricultural residue, was utilized as the feedstock. A technology for producing BC from oat hulls has been developed herein and involves four process operations: exclusive chemical pretreatment with HNO3, enzymatic saccharification, mixed-culture fermentation, and purification. The HNO3 pretreatment was studied under atmospheric pressure at concentrations of 2–6 wt%. The optimum HNO3 concentration for pretreatment of oat hulls was found to be 4 wt%. The pretreatment was run in a 250-L vessel to furnish a pulp in 37.5% yield with 71.5% Kurschner cellulose content. The resultant pulp was well hydrolyzable: enzymatic saccharification with commercial enzymes at an initial solid loading of 30.0 g/L resulted in 79.5% reducing sugar (RS) yield. However, the test synthesis of BC using Medusomyces gisevii showed a very low yield of only 3.5%. It was therefore decided to improve the pulp with the aid of 4 wt% NaOH, whereupon oat-hull cellulose was obtained in 24% yield comprising 93.2% α-cellulose. The enzymatic saccharification of oat-hull cellulose ended with 73.5% RS yield. The test synthesis of BC exhibited 11% yield. Then, the biotechnological stages were scaled up: enzymatic saccharification of oat-hull cellulose was performed in a 100-L fermentor, and BC synthesis in the resultant hydrolyzate was run in a Binder KB-400 incubator. After purification, the BC yield was 10% of the RS concentration. BC was composed of 100% cellulose Iα-allomorph and had 93% crystallinity index. The BC production from oat hulls was thus scaled up successfully with an optimistic BC yield: 80.5 tons of 98%-wet hydrogel per 100 tons of oat hulls.

The extended cultivation with metabolite extraction and the cyclic cultivation of bacterial nanocellulose (BNC) have, for the first time, been examined herein. The biosynthesis of BNC has been scaled up in a 440-L vessel, which is currently the largest scale-up in the world practice.

Molecular nanoribbons with different chemical structures can form scrolled packings possessing outstanding properties and application perspectives due to their morphology. Here, we propose a simplified two-dimensional model of the molecular chain that allows us to describe the molecular nanoribbon's scrolled packings of various structures as a spiral packaging chain. The model allows us to obtain the possible stationary states of single-layer nanoribbon scrolls of graphene, graphane, fluorographene, fluorographane (graphene hydrogenated on one side and fluorinated on the other side), graphone ${\mathrm{C}}_{4}\mathrm{H}$ (graphene partially hydrogenated on one side), and fluorographone ${\mathrm{C}}_{4}\mathrm{F}$. The obtained states and the states of the scrolls found through all-atomic models coincide with good accuracy. We show the stability of scrolled packings and calculate the dependence of energy, the number of coils, and the inner and outer radius of the scrolled packing on the nanoribbon length. It is shown that a scrolled packing is the most energetically favorable conformation for nanoribbons of graphene, graphane, fluorographene, and fluorographane at large lengths. A double-scrolled packing when the nanoribbon is symmetrically rolled into a scroll from opposite ends is more advantageous for longer length nanoribbons of graphone and fluorographone. We show the possibility of the existence of scrolled packings for nanoribbons of fluorographene and the existence of two different types of scrolls for nanoribbons of fluorographane, which correspond to the left and right Archimedean spirals of the chain model. The simplicity of the proposed model allows us to consider the dynamics of molecular nanoribbon scrolls of sufficiently large lengths and at sufficiently large time intervals.

The studies of the condensation of 4-nitrosemicarbazide (4-NSC) with various aldehydes and ketones resulted in the development of an approach to the synthesis of N-nitrosemicarbazones, promising high-energy and biologically active compounds. Subsequent treatment with amines and alkalis led to the synthesis of water-soluble salts of nitrosemicarbazones, as well as the corresponding semicarbazones. The reaction of N,N′-diisopropyl- or N,N′-di-tert-butyl-1,2-ethanediimine with 4-nitrosemicarbazide led to the synthesis of glyoxal bis(nitrosemicarbazone) derivatives. A computer-aided screening using the PASS software showed a probability of high biological activity for the compounds obtained, whereas antiarrhythmic properties of camphor nitrosemicarbazone potassium salt were confirmed in experiments in rats.

The kinetics of the enzymatic hydrolysis of two substrates—lignocellulosic materials from Miscanthus and oat hulls—in an acetate buffer is studied at different concentrations of the substrates. The substrates are obtained via single-step treatment with a dilute solution of nitric acid. The content of a nonhydrolyzable component—acid-insoluble lignin—for Miscanthus and oat hulls was 11 and 14%, respectively. A multi-enzyme composition of commercially available enzyme preparations CelloLux-A and BrewZyme BGX was used as a catalyst. It is shown that treatment with the nitric acid solution produces reactive substrates for the enzymatic hydrolysis. The innovative science of the results is confirmed by Russian patent 2533921. Kinetics of the enzymatic hydrolysis of these substrates in an acetate buffer can be described by a mathematical model based on a modified Michaelis–Menten equation. The main kinetic constants for both substrates are determined from the experimental data. The equilibrium concentrations of reducing substances (RSes) for the substrates are calculated from the initial substrate concentrations. It is found that within the studied range of substrate concentrations (33.3–120.0 g/L), the initial rate of enzymatic hydrolysis for the lignocellulosic material from oat hulls is higher than that for the lignocellulosic material from Miscanthus by 1 g/(L h). It is shown that the yield of RS depends of the initial concentration of the substrates: as the concentration rises from 33.3 to 120 g/L, the yield of RS falls 1.5–2.0 times, due to substrate inhibition. At low initial concentrations, the yields of RS are similar for the substrates from Miscanthus and oat hulls. When the initial concentration of the substrate reaches 120 g/L, the yield of reducing substances for the lignocellulosic material from Miscanthus is approximately 20% higher than that for the lignocellulosic material from oat hulls. The established dependences and the proposed mathematical model allow us to optimize the initial concentration of the substrate for efficient enzymatic hydrolysis.

A nitric acid method for the preparation of cellulose from miscanthus is considered. The method consists in successive treatment of the raw material with nitric acid and sodium hydroxide and affords cellulose with properties suitable for the synthesis of cellulose nitrates. The data on the nitrogen weight fraction, the viscosity, and the solubility of cellulose nitrates from miscanthus in the alcohol-ether medium are given. The miscanthus cellulose was nitrated using an industrial sulfuric-nitric acid mixture to yield cellulose nitrate samples with characteristics close to those of colloxylin.

Furfural 4-nitrosemicarbazone potassium and sodium salts were synthesized. The structures of these compounds were studied by IR and NMR spectroscopy and X-ray diffraction. The computer screening with the PASS program revealed higher biological activity of the salts compared to the starting furfural 4-nitrosemicarbazone.

The chemical composition of the Soranovskii Miscanthus variety harvested in 2011 and 2012 was separately determined in the whole plant, leaves, and stem. In all cases, cellulose was found to prevail in the Miscanthus stem, and non-cellulosic components (the fat-wax fraction, ash, and lignin), in leaves. Cellulose samples were for the first time obtained from leaves and stems separately by two methods (nitric-acid and combined). The best quality cellulose was derived from stems. For instance, cellulose isolated from stems by the nitric-acid process was better than that from leaves, which was expressed as a higher α cellulose content (94,4 % versus 91,7 %) and polymerization degree (800 versus 580), as well as low weight fractions of non-cellulosic components: ash (0,07 % versus 1,01 %) and acid-insoluble lignin (0,45 % versus 1,51 %). The same tendency is observed in celluloses produced by the combined method: Cellulose from stems had better quality than that from leaves; specifically, it had a greater polymerization degree (1040 versus 640) and lower weight fractions of non-cellulosic components: ash (0,14 % versus 0,75 %), acid-insoluble lignin (0,88 % versus 4,2 %), and pentosans (6,8 % versus 8,53 %). It is obvious that cellulose obtained by the nitric-acid method can be suitable for chemical modifications, including nitration. Cellulose from the combined process can be utilized in paper industry.

The concept of manufacturing valuable bacterial nanocellulose (BNC) from plant raw materials having a zero prime cost is substantiated. The process flowsheet involves the chemical transformation of the feedstock to obtain a pulp; enzymatic hydrolysis of the pulp to furnish a solution of reducing sugars, chiefly glucose; preparation of a nutrient broth based on the enzymatic hydrolysate; biosynthesis of nanocellulose microfibrils by the symbiotic Medusomyces gisevii Sa-12 culture; and purification of BNC. BNC has for the first time been synthesized from oat hulls and has a high degree of crystallinity of 88 ± 5% and is composed of 99% Iα-allomorph.

The effect of the surfactant Tween 80 on the efficiency of enzymatic hydrolysis of hydrotropic cellulose pulp from Miscunthus with BrewZyme BGX and CelloLux-A enzyme preparations was studied, which showed that the presence of Tween 80 increased the yields of reducing compounds by 12–13% and pentoses by 14%, with the proportion of pentoses in total reducing compounds being 5.2–5.6%, thus indicating the predominantly glucose composition of the hydrolysate.

Bacterial nanocellulose (BNC) whose biosynthesis fully conforms to green chemistry principles arouses much interest of specialists in technical chemistry and materials science because of its specific properties, such as nanostructure, purity, thermal stability, reactivity, high crystallinity, etc. The functionalization of the BNC surface remains a priority research area of polymers. The present study was aimed at scaled production of an enlarged BNC sample and at synthesizing cellulose nitrate (CN) therefrom. Cyclic biosynthesis of BNC was run in a semisynthetic glucose medium of 10&minus, 72 L in volume by using the Medusomyces gisevii Sa-12 symbiont. The most representative BNC sample weighing 6800 g and having an &alpha, cellulose content of 99% and a polymerization degree of 4000 was nitrated. The nitration of freeze-dried BNC was performed with sulfuric-nitric mixed acid. BNC was examined by scanning electron microscopy (SEM) and infrared spectroscopy (IR), and CN was explored to a fuller extent by SEM, IR, thermogravimetric analysis/differential scanning analysis (TGA/DTA) and 13C nuclear magnetic resonance (NMR) spectroscopy. The three-cycle biosynthesis of BNC with an increasing volume of the nutrient medium from 10 to 72 L was successfully scaled up in nonsterile conditions to afford 9432 g of BNC gel-films. CNs with a nitrogen content of 10.96% and a viscosity of 916 cP were synthesized. It was found by the SEM technique that the CN preserved the 3D reticulate structure of initial BNC fibers a marginal thickening of the nanofibers themselves. Different analytical techniques reliably proved the resultant nitration product to be CN. When dissolved in acetone, the CN was found to form a clear high-viscosity organogel whose further studies will broaden application fields of the modified BNC.

The enzymatic hydrolysis of celluloses obtained via the refinement of fibrous products after the hydro-thermobaric processing (with an explosion) of two types of feedstocks (Miscanthus and oat hulls) in a high-pressure reactor is studied. A multi-enzyme composition of such enzyme preparations as CelloLux-A, BrewZyme BGX, and Rapidase CR, is used as a catalyst. The celluloses obtained by refining fibrous products from the mentioned feedstocks at a pressure of 1.5 MPa are found to have close reactivities: the yield of reducing substances (RS) was 81% (relative to the substrate weight) and 87–91% (relative to the weight of hydrolyzable compounds). When the pressure of the hydro-thermobaric treatment processing of the feedstocks (Miscanthus) is raised from 1.5 to 2.5 MPa, the fermentability of celluloses diminishes: the RS yield was 53–57% (relative to the substrate weight) or 56–60% (relative to the weight of hydrolyzable compounds). The universality of the hydro-thermobaric processing of different non-wood feedstocks for the subsequent successive fermentolysis of substrates into RS solutions that predominantly contain cellulose is shown. The obtained glucose hydrolyzates are high-quality feedstocks for the biosynthesis not only of fuel alcohols, but also a wide spectrum of such microbiosynthesis products as aminoacids, organic acids, bacterial cellulose jelly films, and protein-vitamin concentrates.

The purpose of this work was to study the enzymatic hydrolysis of the fibrous products obtained by the hydro-thermobaric processing (with an explosion) of two types of raw materials, Miscanthus and oat hulls, in a high-pressure reactor. Multi-enzyme composition of the enzyme preparations, such as BrewZyme BGX, CelloLux-A, and Rapidase CR was used as a catalyst. It was found that the fibrous products from oat hulls exhibit the higher reactivity to fermentation as compared to Miscanthus; hydrolysis of the oat hulls processing product in a high-pressure reactor leads to the maximum yield of reducing substances, 68% (relative to the substrate weight) or 95% (relative to the weight of hydrolyzed components) with the predominance of glucose hydrolyzate. In the case of the Miscanthus processing product obtained under the same conditions, the yield of reducing substances was 44% (relative to the substrate weight) or 56% (relative to the weight of hydrolyzed components). The mass fraction of hemicelluloses in the processing products decreased to 0.4% with increasing pressure in hydro-thermobaric processing of Miscanthus; the reactivity of the products to fermentation decreased, the yield of reducing substances was 37% (relative to the substrate weight) or 55% (relative to the weight of hydrolyzed components).

Alkylation of 4(5)-nitro-1,2,3-triazole with alcohols in concentrated H2SO4 occurs at all three endocyclic N atoms, giving a mixture of isomeric N(1)-, N(2)-, and N(3)-alkyl-4-nitro-1,2,3-triazoles (alkyl is isopropyl, sec-butyl, and cyclohexyl). The selectivity of the alkylation depends on the alcohol used. The most selective alkylation is provided at the N(2) atom when isopropyl (81%) and sec-butyl alcohols are used (67%). With an increase in the reaction time, also in the order isopropyl-, sec-butyl-, and cyclohexyl-4-nitro-1,2,3-triazoles, the N(2)-isomers undergo isomerization into N(1)-alkyl-4-nitro-1,2,3-triazoles. In all the cases, the fraction of the N(3)-substitution products in the mixtures is 6–30%.

A ten-step scheme for the preparation of an antiviral agent, ethyl (3R,4R,5S)-4-acetylamino-5-amino-3-(pent-3-yloxy)cyclohex-1-enecarboxylate phosphate, from (-)-shikimic acid was studied. The main parameters of the synthesis were determined and the optimal conditions for the preparation of the intermediate compounds were selected. The total yield of oseltamivir phosphate calculated based on (-)-shikimic acid was 27%.

The interaction of 3-nitro-1,2,4-triazole and 5-methyl-3-nitro-1,2,4-triazole with bifunctional agents - β,β′-dichloro- and β,β′-(dinitroxy)diethyl ethers - in the presence of alkali proceeds with the formation of a mixture of products substituted at the N(1) and N(2) atoms of the heterocycle, consisting of three reaction products, the N(1),N′(1)-, N(1),N′(2)-, and N(2),N′(2) isomeric derivatives of nitrotriazoles. Replacement of the Cl leaving group in the alkylating agent by a NO 2 group does not lead to a substantial change in the degree of conversion and overall yield of alkylation products. The ratio of N(1),N′(1):N(1),N′(2):N(2),N′(2) isomeric reaction products from 3-nitro-1,2,4-triazole was (82.0-85.7): (7.7-9.9):(6.6-8.1), and from 5-methyl-3-nitro-1,2,4-triazole was (76.9-79.8):(10.1:11.4):(10.1-11.7) respectively.

The N-monoalkylation of 3-nitro, 5-methyl-3-nitro, and 5-ethyl-3-nitro-1,2,4-triazoles by epichlorohydrin polymers and copolymers is nonselective in the presence of base. The reaction products are nitrotriazoles substituted by the polymeric chain in positions 1 or 2 of the heterocycle. The mass fraction of the 2-isomer is 9.6-11.3%. The degree of substitution of the chlorine by the nitrotriazole ring is 98.0-99.5%.

A number of problems related to the utilization of nanosize aluminum powders as a combustible component of perspective compositions of high-energy materials is considered. The technology of producing nanopowders using the technique of conductor electrical explosion and the method of dispersed powder composition analysis are shown. The results of experimental studies of conductive and radiant ignition of model propellant compositions containing aluminum nanopowder, as well as the results of investigating the rate of stationary and non-stationary combustion of the given systems, are given. The results of an investigation of the ignition and combustion of ecologically safe propellant systems based on a dual oxidant (ammonium perchlorate and ammonium nitrate, which partially replaces it) containing aluminum nanopowder are demonstrated.