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The effectiveness of the use of new foliar fertilizers and growth regulators for vegetative plants of watermelon in dry-steppe conditions of the Volgograd region has been studied. It was found that the direct supply of nutrients to plants contributed to the progression of growth processes. The maximum plant growth was noted in the variant Vigor Forte + Agrovin Profi + NPK complex, where the excess of the number of lashes to the control was 115%, the length of lashes - 346%. Good development of plants increases their resistance to adverse weather conditions and increases the ability of plants to bear fruit. The maximum effect in increasing the yield was achieved when using Vigor Forte growth regulator in combination with foliar fertilizers - 20.4 t/ha, which is 1.7 times more than the basic technology. It has been determined that the use of water-soluble fertilizers and growth regulators in the cultivation of watermelon makes it possible to obtain high quality products with an amount of nitrates less than the maximum permissible concentration (MPC) - 60 mg/kg. The increase in economic indicators with the use of new foliar fertilizers and growth regulators relative to standard technology ranged from 16,8 to 72,3%.

Catalytic hydrotreatment is a promising technology to convert pyrolysis liquids into intermediates with improved properties. Here, we report a catalyst screening study on the catalytic hydrotreatment of pyrolysis liquids using bi- and tri-metallic nickel-based catalysts in a batch autoclave (initial hydrogen pressure of 140 bar, 350 °C, 4 h). The catalysts are characterized by a high nickel metal loading (41 to 57 wt%), promoted by Cu, Pd, Mo, and/or combination thereof, in a SiO2, SiO2-ZrO2, or SiO2-Al2O3 matrix. The hydrotreatment results were compared with a benchmark Ru/C catalyst. The results revealed that the monometallic Ni catalyst is the least active and that particularly the use of Mo as the promoter is favored when considering activity and product properties. For Mo promotion, a product oil with improved properties viz. the highest H/C molar ratio and the lowest coking tendency was obtained. A drawback when using Mo as the promoter is the relatively high methane yield, which is close to that for Ru/C. 1H, 13C-NMR, heteronuclear single quantum coherence (HSQC), and two-dimensional gas chromatography (GC × GC) of the product oils reveal that representative component classes of the sugar fraction of pyrolysis liquids like carbonyl compounds (aldehydes and ketones and carbohydrates) are converted to a large extent. The pyrolytic lignin fraction is less reactive, though some degree of hydrocracking is observed.

High metal loading NiCu-based catalyst of Picula™ series produced by sol–gel technique was applied to furfural hydrogenation in the presence of hydrogen. This reaction represents the stabilization of pyrolysis oil that involves the selective reduction of aldehydes and ketones to alcohols and unsaturated C–C double bonds of pyrolysis oils components. The catalysts were pre-reduced at 250 and 300 °C. According to XRD analysis results, copper is mainly in the metallic state, and Ni is mostly in the form of oxide and silicate. XPS measurements reveal that hydrogen treatment at 250 °C leads to the partial reduction of Ni to the metallic state (6 %) while further reduction at 300 °C leads to an increase in this proportion up to 39 %. A 100 % selectivity towards furfuryl alcohol was achieved at 130 °C and 5 MPa of hydrogen in a batch reactor using decyl alcohol as a solvent. In the experiments with i-propanol as a solvent at 110–170 °C the main product was furfuryl alcohol, but minor components traced back were tetrahydrofurfuryl alcohol, 2-methylfuran and isopropyl furfuryl ether. The lower catalyst reduction temperature promotes the formation of isopropyl ester, while a higher reduction temperature favors further furfuryl alcohol hydrogenation.

Catalytic hydrotreatment is an attractive technology to convert fast pyrolysis oil to stabilized oil products for co processing in conventional crude oil refinery units. We report here the use of novel bimetallic NiCu- and NiPd-based (Picula) catalysts characterized by a high Ni content (29-58 wt %) and prepared using a sol gel method with SiO2, La2O3, kaolin, ZrO2, and combinations thereof as the support, for the catalytic hydrotreatment of fast pyrolysis oil. The experiments were performed in a batch autoclave (1 h at 150 degrees C, 3 h at 350 degrees C, and 200 bar initial pressure at 350 degrees C). The catalyst with the highest nickel loading (58 wt % Ni) promoted with Pd (0.7 wt %) was the most active, yielding oil products with improved properties compared to the crude pyrolysis oil (lower oxygen content, higher solubility in hydrocarbons, and less tendency for coke formation). For all Picula catalysts, except the ZrO2-based catalysts, methane formation was considerably lower than for Ru/C, the benchmark catalyst in catalytic hydrotreatment of fast pyrolysis oil. To anticipate possible catalyst deactivation at very long times on stream, catalyst regeneration studies were performed using thermogravimetric analysis. Analyses of the regenerated catalysts (X-ray diffraction, high-resolution transmission electron microscopy, and Brunauer Emmett Teller surface area) showed the occurrence of active metal agglomeration.

In this paper, an experimental study on the hydrotreatment of fast pyrolysis liquids is reported in both batch and continuous set-ups using a novel bimetallic Ni–Cu based catalyst with high Ni loading (up to 50%) prepared by a sol–gel method. The experiments were carried out in a wide temperature range (80–410 °C) and at a hydrogen pressure between 100–200 bar to determine product properties and catalyst performance as a function of process conditions. To gain insight into the molecular transformations, the product oils were analysed by GC × GC, 1H-NMR and GPC and reveal that the sugar fraction is reactive in the low temperature range ( 300 °C). In addition, the organic acids are very persistent and reactivity was only observed above 350 °C. The results are rationalized using a reaction network involving competitive hydrogenation of reactive aldehydes and ketones of the sugar fraction of fast pyrolysis liquids and thermal polymerisation. In addition, relevant macro-properties of the product oils including flash point (30 to 80 °C), viscosity (0.06 to 0.93 Pa s) and TG residue (

a b s t r a c t The development of catalysts possessing high activity and high stability in the catalytic hydrotreatment of pyrolysis oils (bio-oil) is of great interest. NiCu bimetallic catalytic systems are very attractive for use in hydrotreatment process due to their low price and high activity in hydrogenation, hydrodeoxygena- tion and hydrocracking reactions. In the present work P-/Mo-containing agents were used to modify bimetallic catalytic system NiCu/SiO2-ZrO2 to improve its mechanical strength and stability in acidic medium. The modified catalysts were tested in hydrodeoxygenation (HDO) of guaiacol—a well-known model compound of bio-oil. HDO process has been carried out in an autoclave at 320 ◦C, 17 MPa initial hydrogen pressure, reaction time 1 h. It was shown that phosphorus and molybdenum addition to the catalysts composition results in the decrease of guaiacol conversion and deoxygenation degree. The yield of undesirable gaseous reaction products (mainly methane) and coking of the catalyst were lower for the modified catalysts in contrast to the initial NiCu/SiO2-ZrO2 system. The catalysts treatment in glacial acetic acid at 118 ◦C showed that modification by P and Mo gives a significant improvement of catalysts stability in acidic medium (mass loss decreases from 53 wt.% to 1 wt.%). Also a significant improvement of bulk crushing strength has been observed for PMo-modified samples (from 0.5 MPa to 1.2 MPa).

The activity of NiCu-SiO2 catalysts with a metal content of 90% and different Ni/Cu ratios has been investigated in the hydrodeoxygenation of anisole, a model compound of bio-oil, at 280°C and 6 MPa. A homogeneous phase composition of the active component has been synthesized by the co-decomposition of nickel and copper nitrates followed by the introduction of SiO2 as a stabilizer. The resulting catalysts have been characterized by temperature-programmed reduction, X-ray powder diffraction, X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy combined with energy-dispersive microanalysis. The bulk and surface composition of active-component particles has been determined by XPS and X-ray diffraction. In all of the catalysts containing 15–85 wt % Ni, there are two types of solid solutions. One has a constant composition, Cu0.95Ni0.05, which is independent of the Ni/Cu ratio in the catalyst; in the other, the nickel stoichiometry increases with an increasing Ni content of the active component. A correlation has been established between the Ni/Cu ratio and the rate constants of the reaction examined and between the Ni/Cu ratio and the degree of hydrodeoxygenation for all samples. The most active catalyst is Ni85Cu5-SiO2.

The hydrodeoxygenation of guaiacol, a compound modeling bio-oil, has been investigated. Experiments have been carried out in an autoclave at 280, 320, and 360°C and an initial hydrogen pressure of about 17 MPa using a Ni-Cu/SiO2-ZrO2-La2O3 catalyst. A formal kinetic model of the first stage of guaiacol hydrodeoxygenation is suggested. It is assumed that the reaction is first-order with respect to both guaiacol and hydrogen. The model takes into account the deactivation of the catalyst and the decrease in the concentration of the deactivating compounds due to their hydrogenation. A possible cause of deactivation is the formation of coke and heavy intermediates, as well as the competitive adsorption of intermediate products of guaiacol conversion on the active sites of the catalyst. The parameters with which the model satisfactorily fits the observed dependence of the guaiacol concentration on the reaction time have been determined.

Heterogeneous catalysts for the hydrotreatment (hydrodeoxygenation) of biomass fast pyrolysis products (bio-oil) for the production of fuel hydrocarbons are considered. Hydrodeoxygenation catalysts are conventionally divided into three groups: catalysts based on noble metals, sulfided catalysts for desulfurization, and non-sulfided catalysts based on supported transition metals. The main emphasis in this work is on nickel-based non-sulfided catalytic systems as the ones most promising for the hydrotreatment of feedstocks with low content of sulfur. In light of specific features of bio-oil (high acidity and viscosity, low thermal stability), requirements are formulated that must be met in developing hydrodeoxygenation catalysts and processes based on them, especially specifications for the stability of catalysts of this type and their ability for multiple regeneration.

Catalytic hydrotreatment or hydrodeoxygenation (HDO) has been researched extensively with the crude bio-oil and its model compounds over conventional sulfided Ni(Mo), Co(Mo) catalysts and supported noble metal catalysts. These types of catalysts showed themselves unsuitable for the target HDO process, which resulted in an urgent need to search for a new catalytic system meeting such requirements as low cost, stability against coke formation and leaching of active components due to adverse effect of the acidic medium (bio-oil). In the present work a series of Ni-based catalysts with different stabilizing components has been tested in the hydrodeoxygenation (HDO) of guaiacol (2-methoxyphenol), bio-oil model compound. The process has been carried out in an autoclave at 320 °C and 17 MPa H2. The main products were cyclohexane, 1-methylcyclohexane-1,2-diol, and cyclohexanone. The reaction scheme of guaiacol conversion explaining the formation of main products has been suggested. The catalyst activity was found to rise with an increase in the active component loading and depend on the catalyst preparation method. The most active catalysts in HDO of guaiacol were Ni-based catalysts prepared by a sol–gel method and stabilized with SiO2 and ZrO2. According to TPR, XRD, XPS, and HRTEM, the high activity of these catalysts correlates with the high nickel loading and the high specific area of active component provided by the formation of nickel oxide–silicate species. The effect of temperature on the product distribution and catalyst activity in the target process (HDO) has been investigated as well. The catalysts were shown to be very promising systems for the production of hydrocarbon fuels by the catalytic upgrading of bio-oil.

This paper describes the concept of energy security and a system of indicators for its monitoring. The indicator system includes more than 40 parameters that reflect the structure and state of fuel and energy complex sectors (fuel, electricity and heat & power), as well as takes into account economic, environmental and social aspects. A brief description of the structure of the computer system to monitor and analyze energy security is given. The complex contains informational, analytical and calculation modules, provides applications for forecasting and modeling energy scenarios, modeling threats and determining levels of energy security. Its application to predict the values of the indicators and methods developed for it are described. This paper presents a method developed by conventional nonlinear mathematical programming needed to address several problems of energy and, in particular, the prediction problem of the security. An example of its use and implementation of this method in the application, "Prognosis", is also given.

A series of Ni-containing catalysts supported on different materials has been tested in the hydrodeoxygenation of guaiacol, a compound modeling the products of biomass fast pyrolysis. The reaction has been carried out in an autoclave at 320°C and a hydrogen pressure of 17 MPa. The main guaiacol hydrodeoxygenation products are cyclohexane, 1-methylcyclohexane-1,2-diol, and cyclohexanone (which result from aromatic ring reduction). A guaiacol conversion scheme explaining the formation of the main products is suggested. The highest activity is shown by the Ni-containing catalysts on SiO2 and SiO2-ZrO2 supports prepared by the sol-gel method. According to X-ray diffraction and electron microscopic data, the high activity of these catalysts is due to the high concentration of dispersed nickel as reduced films on the surface of the silicate structures. The catalysts offer promise for refining the biomass fast pyrolysis products (bio-oil) into hydrocarbon fuel.

The possibility of making titanium tooth crowns by superplastic molding has been investigated. Optimal materials and technological parameters have been selected: Siolit molding mass, fixing composition for facing with plastic (Targit link + opaquer), method for tooth preparation under such crowns (step 135, stump height to diameter ratio 1.5:1, smooth transfer from occlusion surface to others, and disposition of stamps in the press form.

The results are available on introduction of interference therapy in 30 children with bronchial asthma versus control group of 20 untreated patients. Bronchoprovocative histamine and exercise tolerance tests have specified characteristic features of interference current effects on bronchial permeability and hyperreactivity.