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In this paper we analyze differences in fatty acid methyl ester (FAME: methyl palmitate, methyl octanoate), fatty acid ethyl ester (FAEE: ethyl laurate), and triglyceride (TG – tricaprylin) hydrodeoxygenation (HDO). These differences are attributed to chemical nature of FAME, FAEE, and TG, and different reaction rates of the initial compounds. The HDO experiments were carried out in continuous flow fixed bed reactor at 250–330 °C and 3 MPa. Ni2P supported on SiO2, SBA-15, or Al2O3were used as catalysts. The rates of O removal for FAME, FAEE, and TG are the same for the catalyst with high acidity (Ni2P/Al2O3), but different for the catalyst with low acidity (Ni2P/SiO2). It turned out that the rate of fatty acid conversion is significantly higher at the same conditions compared to the initial esters. Thus, it was concluded that TG rapidly transforms to fatty acid and there is almost no influence of catalyst acidity on the TG HDO rate, i.e., no synergetic effect of metal and acid sites can be obtained for TG HDO.

ABSTRACTThe purpose of the article is to analyse the manufacturing factors that affect the cost of manufacturing a part. Nowadays the cost of equipment used for metal 3D printing, as well as metal powders, are still very expensive. The cost of additive manufacturing of metal parts is mainly dependent on the volume of printing, therefore, reducing the volume of printing can lead to a significant reduction in the cost of manufacturing the part. Manufacturing of a metal shell, the cavity of which is filled with a cheap metal polymer, can be an excellent alternative to an all-metal part. The article provides a method for calculating the cost of manufacturing a lever part using various technologies: subtractive, additive, and composite part manufacturing technology. According to the calculated data, the dependence of the cost of manufacturing a part on piece time has been built, which can be interpreted as the amount of machining. The constructed linear dependence can give an idea of the effectiveness of the application of a particular technology for obtaining a part. In addition, non-economic factors affecting the possibility of using various technological processes for manufacturing a part are described.

The effect of different types of alcohols used as hydrogen donors on the activity of a metal Ni-based catalyst in the hydrogenation of benzofuran as a model substrate under transfer hydrogenation conditions has been studied. The hydrogenation process of benzofuran using 2-PrOH as a hydrogen donor leads sequentially to dearomatization and then to deoxygenation of the substrates. At the same time, the use of primary alcohols such as MeOH, EtOH and 1-PrOH as hydrogen donors leads to irreversible deactivation of the Ni-containing catalyst. A clear mechanism of deactivation of Ni-based metal catalysts by primary alcohols has been established. The interaction of the catalyst with primary alcohols at a temperature of 250 °C leads to the formation of an inactive Ni3C carbide phase, as well as sintering and segregation of metal particles on the surface of the alumina support.

We establish three criteria of hyperbolicity of a graph in terms of “average width of geodesic bigons”. In particular we prove that if the ratio of the Van Kampen area of a geodesic bigon βand the length of βin the Cayley graph of a finitely presented group Gis bounded above then Gis hyperbolic.

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The article presents the results of the analysis of the current state of weather and climatic conditions and evaluation of their predicted changes for immediate and distant prospects in the rice-growing zone of Ukraine. Studies were performed on the example of the Danube rice irrigation systems (RIS) in Odessa region with a total area of 13,678 ha, which are located in lands prone to salinization. The following major meteorological characteristics were investigated: air temperature, precipitation, relative humidity and air humidity deficit, as well as derivatives: photosynthetically active radiation and water availability coefficient (precipitation/evapotranspiration ratio). Retrospective analysis and forecast of meteorological regimes by typical groups were done (estimated years) of vegetation periods of target years in view of general heat and moisture provision: very wet—p= 10%, wet—p= 30%, middle—p= 50%, dry—p= 70%, very dry—p= 90%. The basis of forecast calculations is the results of studies of possible changes of air temperature by the models of Canadian Climate Center “CCCM” and of the United Kingdom Met Office “UKMO” which foresee an increase in average annual temperature up to 4 °C and 6 °C relatively—provided that the doubling CO2in atmosphere occurs. The main trends in changes of meteorological characteristics and their possible effect on the conditions of functioning rice irrigation systems as well as on the natural and ameliorative state of irrigated areas were identified. The most significant influence on the condition of fonctioning of RIS is air temperature, which directly effects duration of maturation and total value of water consumption of rice crops. It is established that in the last decades a significant increase in the average value of air temperature for the growing season happened (April–October): 1981–1990—16.9 °C, 1991–2000—17.5 °C, 2001–2010—18.1 °C, 2011–2017—17.7 °C. It is determined that at the existing rates and levels of weather and climatic changes, we should expect a significant deterioration of functioning conditions of RIS and natural reclamation state of irrigated land. In this regard, were examined core measures regarding the adaptive potential enhancement and development of the rice-growing zone under the conditions of climate change.

Abstract: Typomorphic features of placer gold are carriers of important information necessary for reconstruction of the formation history of gold placers and can be used as mineralogical criteria to search primary sources. The internal structure of grains of native gold is one of the most informative features. Internal structures of gold grains from modern placers and Early Permian conglomerates in the northeast of the Siberian Platform are studied. Structural etching of native gold was performed using the reagent (HCl + HNO3+ FeCl3⋅6H2O + CrO3+ thiurea + water). It was found that the well-rounded high-grade gold grains from modern placers experienced repeated redeposition through intermediate reservoirs. The discovery of slightly rounded gold grains, the internal structure of which bear no signs of exogenous transformation indicates that they were supplied to the modern alluvium from a nearby primary source. Apo-carbonate hydrothermal–metasomatic formations with the disseminated gold-sulfide mineralization were identified in the course of gold-ore exploration.

Solid-state guest exchange is used as an efficient method to prepare very metastable polymorphs of indomethacin, including the polymorph observed earlier only in a mixture with a polymeric solvent and a new crystalline form of this drug with a negligibly small amount of the included solvent (guest). The used preparation procedure gives less stable inclusion compounds of indomethacin, which require a milder desolvation treatment than inclusion compounds formed in binary host–guest systems, so the metastable forms with a low first melting point can be prepared. For the characterization of indomethacin polymorphs, fast scanning calorimetry was used, along with conventional characterization methods. This method merges multistep polymorphic transitions, making the first melting point much more pronounced, so the different polymorphs become better discriminated.

Most complex human traits differ by sex, but we have limited insight into the underlying mechanisms. Here, we investigated the influence of biological sex on protein expression and its genetic regulation in 1,277 human brain proteomes. We found that 13.2% (1,354) of brain proteins had sex-differentiated abundance and 1.5% (150) of proteins had sex-biased protein quantitative trait loci (sb-pQTLs). Among genes with sex-biased expression, we found 67% concordance between sex-differentiated protein and transcript levels; however, sex effects on the genetic regulation of expression were more evident at the protein level. Considering 24 psychiatric, neurologic and brain morphologic traits, we found that an average of 25% of their putatively causal genes had sex-differentiated protein abundance and 12 putatively causal proteins had sb-pQTLs. Furthermore, integrating sex-specific pQTLs with sex-stratified genome-wide association studies of six psychiatric and neurologic conditions, we uncovered another 23 proteins contributing to these traits in one sex but not the other. Together, these findings begin to provide insights into mechanisms underlying sex differences in brain protein expression and disease.

Seamless integration between biological systems and electrical components is essential for enabling a twinned biochemical–electrical recording and therapy approach to understand and combat neurological disorders. Employing bioelectronic systems made up of conjugated polymers, which have an innate ability to transport both electronic and ionic charges, provides the possibility of such integration. In particular, translating enzymatically polymerized conductive wires, recently demonstrated in plants and simple organism systems, into mammalian models, is of particular interest for the development of next-generation devices that can monitor and modulate neural signals. As a first step toward achieving this goal, enzyme-mediated polymerization of two thiophene-based monomers is demonstrated on a synthetic lipid bilayer supported on a Au surface. Microgravimetric studies of conducting films polymerized in situ provide insights into their interactions with a lipid bilayer model that mimics the cell membrane. Moreover, the resulting electrical and viscoelastic properties of these self-organizing conducting polymers suggest their potential as materials to form the basis for novel approaches to in vivo neural therapeutics.

The influence of Microarc Oxidation (MAO) modes of titanium substrate in electrolytes of the original composition is investigated. Used electrolytes no contain sodium silicate but includes nickel sulphate, sodium aluminate and alkali. The morphology and composition of the obtained coatings were studied by electron microscopy. The electrochemical behaviour was studied using polarisation curves and electrochemical impedance spectroscopy (EIS). Proposed Equivalent circuits are adequately corresponded to experimental EIS data with no more 6% error. The dependence between the elements of the Equivalent circuits and the morphological characteristics depending on the processing is considered. It is shown that MAO coatings on titanium have high corrosion resistance in an aggressive sulphuric acid. The electrochemical properties of coatings undergo irreversible changes in the direction of deterioration after anodic polarisation. It has been established that nickel doping of MAO coatings on titanium does not allow them to serve as anode materials.

Lithium metal batteries are one of the promising technologies for future energy storage. One open challenge is the generation of a stable and well performing Solid Electrolyte Interphase (SEI) between lithium metal and electrolyte. Understanding the complex interaction of reactions at the lithium surface and the resulting SEI is crucial for knowledge-driven improvement of the SEI. This study reveals the internal species distribution and geometrical aspects of the native SEI during formation by model-based analysis. To achieve this, a combination of molecular dynamics, density functional theory, and stand-alone 3D-kinetic Monte Carlo simulations is used. The kinetic Monte Carlo model determines the SEI growth features over a long time and length scale so that the SEI can be analyzed quantitatively. The simulation confirms the frequently postulated layered SEI structure arising from the decomposition of an ethylene carbonate/lithium hexafluorophosphate (2 M) electrolyte with lithium metal. These layers are not clearly separated, which is contrary to what is often reported. The gradient distribution of the species within the SEI therefore corresponds to a partly mosaic structured SEI at the borders of the layers. At the lithium surface, an inorganic layer of lithium fluoride and then lithium carbonate is observed, followed by an organic, more porous SEI layer consisting of lithium ethylene dicarbonate. Simulations further reveal the strong prevalence of corrosion processes of the metal, which provide more than 99% of the lithium for the SEI reaction processes. The salt contributes less than 1% to the SEI formation. Additionally, SEI formation below and above the initial interface was observable. The here presented novel modeling approach allows an unprecedented in-depth analysis of processes during native SEI formation that can be used to improve design for high battery performance and durability.

ABSTRACTThe influence of Microarc Oxidation (MAO) modes of titanium substrate in electrolytes of the original composition is investigated. Used electrolytes no contain sodium silicate but includes nickel sulphate, sodium aluminate and alkali. The morphology and composition of the obtained coatings were studied by electron microscopy. The electrochemical behaviour was studied using polarisation curves and electrochemical impedance spectroscopy (EIS). Proposed Equivalent circuits are adequately corresponded to experimental EIS data with no more 6% error. The dependence between the elements of the Equivalent circuits and the morphological characteristics depending on the processing is considered. It is shown that MAO coatings on titanium have high corrosion resistance in an aggressive sulphuric acid. The electrochemical properties of coatings undergo irreversible changes in the direction of deterioration after anodic polarisation. It has been established that nickel doping of MAO coatings on titanium does not allow them to serve as anode materials.

Antifungal medicines currently used clinically become less efficient regarding microscopic fungi due to new infectious agents emerging among fungi and a wide range of pathogenic factors in micromycetes. In developing new antifungal medicines, a comprehensive approach is needed that would consider the adaptive properties of fungi. This paper aims to study the antifungal activity of the synthesized compounds on yeast and mycelial fungi. In our study, we assessed the changes in the pathogenic factors of fungi, such as germination and hypha-forming intensity and sporulation, while cultivating them as affected by the compounds under study. This manuscript describes the antifungal activity of the bornane series thioterpenoids. Compound 8demonstrated a strong antimycotic activity on all fungi species, including Candida albicans(laboratory and clinical stains), Aspergillus niger, and Fusarium solani(MIC 12, 24, 94, and 94 μg/ml, respectively). A. nigersporulation index analysis demonstrated the highest spore production rate at day 6 of culturing in non-treated samples (control) and in those treated with compounds 3, 6, and 7, whereas the highest sporulation of A. nigercultured in the presence of compound 8was substantially delayed and observed on day 10 of culturing. The lowest level of fungi reproduction was observed over the entire period of experiments for the cultures treated with terbinafine or compound 8. In addition, compound 8, fluconazole, and terbinafine had an inhibitory effect on the germination tubes of C. albicansat a concentration of ½ MIC.

Bioisosteres are molecules that differ in substituents but still have very similar shapes. Bioisosteric replacements are ubiquitous in modern drug design, where they are used to alter metabolism, change bioavailability, or modify activity of the lead compound. Prediction of relative affinities of bioisosteres with computational methods is a long-standing task; however, the very shape closeness makes bioisosteric substitutions almost intractable for computational methods, which use standard force fields. Here, we design a quantum mechanical (QM)-cluster approach based on the GFN2-xTB semi-empirical quantum-chemical method and apply it to a set of H → F bioisosteric replacements. The proposed methodology enables advanced prediction of biological activity change upon bioisosteric substitution of −H with −F, with the standard deviation of 0.60 kcal/mol, surpassing the ChemPLP scoring function (0.83 kcal/mol), and making QM-based ΔΔGestimation comparable to ∼0.42 kcal/mol standard deviation of in vitroexperiment. The speed of the method and lack of tunable parameters makes it affordable in current drug research.

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The paper considers the control problem for a class of uncertain linear time-varying systems. The time-varying (TV) parameters are represented by multisinusoidal functions with a priori unknown amplitudes, phases, and frequencies of harmonics. The maximum numbers of the harmonics are known. To compensate the influence of the TV parameters on the closed-loop system, based on internal model principle,TV parameters observers are designed, and the plant model is represented in the parameterized form with constant unknown parameters. This form is used for design of adaptive backstepping controller with modular identifierswith improved parameters tuning.

The paper concerns the problem of adaptive compensation of unmatched disturbances in linear time-invariant (LTI) multi-input multi-output (MIMO) unstable plants with multiple distinct input delays. The external disturbances affect both the input and the output of the plant and are represented by multi-harmonic signals with unknown parameters (frequencies, phases, and amplitudes). The paper extends results of the paper Nikiforov et al. (2021) on adaptive compensation of unmatched disturbances to the case of distinct input delays. To overcome the problem of multiple distinct input delays, a special scheme of the disturbance prediction is proposed and used for design of the adaptive control law.

Equilibrium in the quaternary CaO–P2O5–H2CO3–H2O system at 298 K in air was studied in a region of low concentrations of liquid-phase components. We revealed a dependence of the composition of resultant equilibrium solid phases on the Ca/P ratio of the initial components and on pH of the equilibrium liquid phase. It was found that the entire region of the system having low concentrations of liquid-phase components is occupied by variable-composition compounds with apatite structure. Two types of carbonate-containing apatite compounds were detected. The first type of apatite forms at 5.4 ≤ pH ≤ 7.0, contains HPO42−groups in the lattice, and has an invariant point with brushite CaHPO4·2H2Oat pH ≈ 5.4. The second type arises at pH > 7.0, does not contain an acidic group, and has an invariant point with CaCO3at pH ≥ 8.

The paper addresses the problem of transient performance improvement in the output-feedback adaptive backstepping control of parametrically uncertain nonlinear system represented in the cascaded output-feedbackform. The system state is inaccessible for measurement, the system input is constrained, and the control gain is assumed unknown (its sign is known). The problem is solved by applying specially modified K-filters with adjustable parameter, using the backstepping procedure taking into account the input constraints, and involving the Kreisselmeier-like adaptation algorithm with a modified swapping scheme. The algorithm enables us to improve the closed-loop transient performance without increasing initial “swings” in the control error transients. The latter property is achieved by including the high-order time derivatives of the adjustable parameters, calculated by the adaptation algorithm, in the control law. The properties of the closed-loop system are illustrated via simulation.

The paper presents the results of theoretical studies on turbulent water motion in pipelines, obtained by the analysis of experimental data regarding hydraulic patterns of turbulent flows. The authors suggest to evaluate the relevant parameters on the basis of the molecular and turbulent viscosity indicators, with the introduction of the conditional relative thickness of the boundary layer on the pipeline walls into the calculations. On this basis, the authors specified semi-empirical relationships for the distribution of averaged velocities in the pipe cross-sections, and revealed new theoretical relationships between the main parameters of turbulent pipe flows. The research confirmed the adequacy of these relationships given the good agreement of the calculated averaged velocity values with the experimental data which formed a basis for the current standards for hydraulic calculations of water supply pipes. For hydraulically smooth pipes, the authors derived an explicit dependence of the hydraulic friction coe cient on the Reynolds number, which almost completely corresponds to the well-known Prandtl-Colebrook equation that has an implicit form. The presented research allowed to determine numerical values and analytical relationships between parameters, which enabled evaluating turbulent flows in hydraulically smooth pipes in a new way.