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The article provides an analysis of the bearing capacity of barrett piles in difficult geological conditions at a construction site in the city of Hanoi, Vietnam based on the results of analytical calculations according to Russian building codes, mathematical modeling and field full-scale tests. The paper describes a numerical test of a single barrette for Mohr-Coulomb and Hardening Soil models in the Midas GTS NX software package. The bearing capacity of a barrette in soft soils is also proposed to be determined by an analytical solution for calculating the settlement of a single pile, taking into account the unloading of the pit after soil excavation. The results of full-scale tests at the site of future construction, graphs of "load-settlement" of the barrette head from the applied vertical load and the general assessment of the bearing capacity of the barret pile by various methods are shown.

The term “hippotherapy” can be defined as physiotherapy treatment “one patient – one horse”, meaning communication with a horse and riding. The main tasks of hippotherapy are to regulate muscle tone (reduce spasticity) and improve breathing, strengthen the muscles of the trunk, improve balance control and coordination, as well as improving control over walking. The aim of the study was to provide an example of the effectiveness of hippotherapy in the complex therapy of multiple sclerosis. Materials and Methods. An analysis of the literature and a clinical case of a 52‑year-old female patient with multiple sclerosis who underwent a single course of hippotherapy was presented. The following tests, questionnaires and scales: Wakefield Self-Assessment and Depression Scale, Spielberger-Hanin Self-Assessment Scale, SAN Questionnaire, Hamilton Anxiety Scale (HAM-A), Hamilton Depression Scale (HAM-D), Hospital Anxiety and Depression Scale (HADS), Beck Depression Scale. Results. The patient had both positive results on the basis of tests, questionnaires and scales, and on subjective self-awareness. Conclusion. The clinical case demonstrates the effectiveness and the need to consider hippotherapy in the course of medical rehabilitation and psychosocial support of patients with multiple sclerosis, not only with its mild forms, but also with severe forms, as in our observation.

The various energy pathways of Au20(SCH3)16 oxidation were simulated in the gas phase and on a CeO2 surface at the density functional theory/Perdew–Burke–Ernzerhof (DFT/PBE) level. Due to the high ...

Features of various Fe-containing nanosized slurry Fischer–Tropsch catalysts, obtained in situ by thermolysis, were investigated experimentally (catalytic tests, XRD, hermomagnetometric methods) and theoretically (DFT ab initio calculations, regression analysis). XRD patterns of the samples reveal the presence of preferentially single Fe7C3, Fe5C2 and Fe2C. A quantitative correlation was found between the values of the most important hydrocarbon group selectivity at 260 °C and the residual magnetization of the spent samples, regardless of promoter nature and amount. The Fe7C3 model clusters, according to the DFT results, prefer to be in high-spin states and substantiate the preference of associative coordinated CO. Because the CO associative sorption is unfavourable for chain growth on Fe Fischer–Tropsch catalysts and the carbides have Curie points

The oxidation of CO over Pt and Pt–Co catalysts was studied both experimentally and by quantum-chemistry calculations. Density functional theory simulation shows that CO is oxidized on Pt13 via dissociative oxygen adsorption. The calculated activation energy for the dissociation of O2 on Pt13 is 56 kJ/mol. It is found that when a cobalt atom is introduced into the cluster, the activation energy falls for the stages of CO oxidation and the dissociation of O2. Catalytic tests performed on Pt and Pt0.5Co0.5 nanopowders confirm the Pt–Co system displays high activity in the oxidation of CO.

The interaction of CO and O2 and the subsequent oxidation of CO in the presence of cyclic thiolate and dithiolate complexes of Au(I), which represent the model fragments of thiolate-protected gold clusters, were studied using the density functional theory (PBE). On the basis of the calculated values, it was shown that O2 and CO were weakly bound to a cyclic thiolate complex of Au(I). In the presence of a dithiolate complex, the activation of O2 and CO and the subsequent oxidation of CO occurred with low activation energies. The results obtained demonstrate the important role of ligands in the catalytic process.

The article is devoted to results of systematic study of the structure transformation of V2O5 supported on TiO2 (anatase). The effect of (001) TiO2-anatase on the structural properties and morphology of V2O5 was analyzed using the spin-polarized density functional theory (DFT) in the periodic approach. The calculations were performed using the VASP code with PBE energy functional and plane wave basis set. The catalyst is represented as a periodic surface. The supercell includes four Ti – O layers and the top V2O5 layer. A lot of different forms of V2O5 (monomeric and polymeric structures, individual crystallites) on the TiO2 surface were considered. According to the calculations of the adsorption energy, vanadium oxide on the oxide composite surface can form various forms. The monomeric form is the most stable. Calculated value of adsorption energy is -1.16 eV. The ionic interaction causes a significant change in the interatomic distances between the vanadium atom and the oxygen atom from the support d (V – O (Ti)) for all active forms. The highest value d (V – O (Ti)) was found for catalyst with the polymeric active form. It suggests that the binding of the form with the anatas is the smallest. Theoretical studies have shown that the V2O5/TiO2 system is dynamic and can change the surface structure under the different conditions.

The results of static testing of the pile and comparative results of analytical and numerical calculations for the experimental deep pile (length 65 m, diameter 1.2 m) under the high-rise building, designed in the area of a large thickness of weak soils, are presented in the paper. At the same construction site, an experimental barrette pile of rectangular crosssection with a size of 3.3 x 1.1 and a length of 65 m with the location of the base in solid Proterozoic clays was made. This pile was tested with the use of Osterberg cells, for which strain gauges were mounted in its reinforcement cage at 9 levels. In the first stage, a standard test of the entire experimental barrette pile in the top-down direction was conducted; in the second, after reaching the maximum possible load, the tests were carried out using the “O-cells” located at a depth of 50 m in the thickness of solid clays and transmitting the load in two directions (up and down). A General assessment of the bearing capacity of the barrette pile obtained by three methods is given.

42-01-09/169/2021-4 CTQ2017-86170-R Au and Ag were deposited on TiO2 modified with Ce, La, Fe or Mg in order to obtain bimetallic catalysts to be used for liquid-phase oxidation of 1-octanol. The effects of the deposition order of gold and silver, and the nature of the support modifying additives and redox pretreatments on the catalytic properties of the bimetallic Au-Ag catalysts were studied. Catalysts were characterized by low-temperature nitrogen adsorption–desorption, energy dispersive spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy and ultraviolet-visible diffuse reflectance spectroscopy. It was found that pretreatments with hydrogen and oxygen at 300◦C significantly decreased the activity of AuAg catalysts (silver was deposited first) and had little effect on the catalytic properties of AgAu samples (gold was deposited first). The density functional theory method demonstrated that the adsorption energy of 1-octanol increased for all positively charged AuxAgyq (x + y = 10, with a charge of q = 0 or +1) clusters compared with the neutral counterparts. Lanthanum oxide was a very effective promoter for both monometallic and bimetallic gold and silver catalysts in the studied process. publishersversion published

This study aims to identify the role of the various electronic states of gold in the catalytic behavior of Au/MxOy/TiO2 (where MxOy are Fe2O3 or MgO) for the liquid phase oxidation of n-octanol, under mild conditions. For this purpose, Au/MxOy/TiO2 catalysts were prepared by deposition-precipitation with urea, varying the gold content (0.5 or 4 wt.%) and pretreatment conditions (H2 or O2), and characterized by low temperature nitrogen adsorption-desorption, X-ray powder diffraction (XRD), energy dispersive spectroscopy (EDX), scanning transmission electron microscopy-high angle annular dark field (STEM HAADF), diffuse reflectance Fourier transform infrared (DRIFT) spectroscopy of CO adsorption, temperature-programmable desorption (TPD) of ammonia and carbon dioxide, and X-ray photoelectron spectroscopy (XPS). Three states of gold were identified on the surface of the catalysts, Au0, Au1+ and Au3+, and their ratio determined the catalysts performance. Based on a comparison of catalytic and spectroscopic results, it may be concluded that Au+ was the active site state, while Au0 had negative effect, due to a partial blocking of Au0 by solvent. Au3+ also inhibited the oxidation process, due to the strong adsorption of the solvent and/or water formed during the reaction. Density functional theory (DFT) simulations confirmed these suggestions. The dependence of selectivity on the ratio of Brønsted acid centers to Brønsted basic centers was revealed., This work was partially supported by the Associate Laboratory for Green Chemistry—LAQV, and financed by national funds from FCT/MCTES (UIDB/50006/2020)(Portugal), Tomsk Polytechnic University Competitiveness Enhancement Program, project VIU-RSCBMT-65/2019 and Russian Foundation of Basic Research, project 18-29-24037 (Russia), and MINECO project CTQ2017-86170-R (Spain).

A procedure based on density functional theory is proposed for calculation of Au20(ХCH3)16 (Х = S, Se, Te) isomers. It is established that the most stable isomer for all X has a core‒shell structure: Au7@(AuXCH3)8(XCH3(AuXCH3)3)(XCH3AuXCH3)2. Optical and IR spectra, ionization potential, and electron affinity are calculated for the first time for all clusters. It is shown that a cluster protected by thiolate ligands has the greatest electronic and thermodynamic stability.

CO preferential (PROX) and total (TOX) oxidation were studied over Pt and Pt0.5Co0.5 nanopowders. Pt0.5Co0.5 exhibited much higher CO PROX performance than Pt, being highly active and selective at 0–80 °C. Low-temperature activity in CO oxidation was shown to be the key feature of bimetallic Pt-Co catalysts in comparison with monometallic Pt. Density functional theory calculations of the oxidation of CO on Pt13 and Pt12Co clusters revealed that a better catalytic activity of bimetallic cluster is due to an electronic effect: the calculated atomic charges on platinum atoms change when cobalt is introduced into its composition.

The article presents the published date on the prevalence, the main clinical manifestations, modern methods of early neonatal and postnatal diagnosis, treatment and prognosis for tetralogy of Fallot — a congenital malformation of cardiovascular system., В статье представлены литературные данные о частоте, основных клинических проявлениях, современных методах ранней неонатальной и постнатальной диагностики, лечении и прогнозе тетрады Фалло — врожденном пороке сердечно-сосудистой системы., У статті наведено літературні дані щодо частоти, основних клінічних проявів, сучасних методів ранньої неонатальної та постнатальної діагностики, лікування та прогнозу тетради Фалло — уродженого пороку серцево-судинної системи.

The article presents the published data on the prevalence, the main clinical manifestations, modern methods of early neonatal and postnatal diagnosis, treatment and prognosis for total non-correctable transposition of the great vessels — a congenital malformation of cardiovascular system., В статье представлены литературные данные о частоте, основных клинических проявлениях, современных методах ранней неонатальной и постнатальной диагностики, лечении и прогнозе полной некорригированной транспозиции магистральных сосудов — врожденном пороке сердечно-сосудистой системы., У статті наведено літературні дані щодо частоти, основних клінічних проявів, сучасних методів ранньої ­неонатальної і постнатальної діагностики, лікування і прогнозу повної некоригованої транспозиції магістральних судин — уродженого дефекту серцево-судинної системи.

This paper attempt to apply the maximum principle to the design of optimal control for manipulation robots essentially resting upon the specifies of the mechanical system motion equations. This leads to the problem of mathematical programming. The iterative method is suggested for construction of optimal controls for manipulation robots