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  • China's high-rise building construction technologies and high-rise building designs

    This article provides a comprehensive overview of the primary technologies used in the construction of high-rise buildings in China. It delves into the most commonly employed construction techniques and the types of structures that are prevalent in this sector. The study is based on a thorough analysis of existing literature and showcases real-world examples to illustrate the application of these technologies. These techniques encompass various construction methods and material choices, which are critical in the successful erection of skyscrapers. The aim of this paper is to offer reference information for professionals, aiding them in selecting suitable technologies and structural types for high-rise building projects. This work is especially useful for those in the construction industry, as it highlights the significant role that building technologies play in high-rise construction. It serves as a practical guide, providing insights into the most widely used construction technologies in the field. This article is intended to be a valuable resource for specialists looking to employ advanced methods in their construction practices, thereby enhancing the efficiency and sustainability of high-rise buildings.

    Keywords: civil engineering, high-rise buildings, construction technology, reinforced concrete structure, prefabricated structure, analysis

  • Determination of the atomic structure of bimetallic Pt-Ag nanoparticles in metal-carbon catalysts by X-ray absorption spectroscopy data

    The atomic structure of bimetallic nanoparticles of Pt-Ag composition, which are the part of metal-carbon electro-catalysts PtAg/C, is studied by means of EXAFS spectroscopy using the suggested technique. These materials have been prepared by methods of consistent and simultaneous deposition of Ag and Pt atoms from aqueous ethylene glycol solutions of their salts with subsequent acid treatment. The values ​​of the structural parameters of the near environment of platinum atoms are determined. The nature of the distribution of components in nanoparticles is established. Cluster models of nanoparticles are constructed. The fraction of Pt atoms in the working shell and its dependance on preparation methods in each case are determined.

    Keywords: Metal-carbon electrocatalysts, bimetallic nanoparticles, Catalysis, Platinum, X-ray absorption spectroscopy, atomic structure

  • Local Atomic and Electronic Structure of the Fe dopants in AlN:Fe Nanorods

    Fe-doped AlN nanorods were studied by means of x-ray absorption spectroscopy above the Fe K- and L2,3- edges. Theoretical simulations of the x-ray absorption spectra show that Fe atoms mainly substitute Al. A minor fraction of Fe interstitials or Fe-Al-N ternary alloy can be identified as well. Bader’s AIM analysis predicts that neutral substitutional FeAl defect is in 2+ charge state, though Al in pure AlN is in 3+ charge state.  Fe L2,3 absorption spectra and photoluminescence data indicate the coexistence of Fe2+/Fe3+ in AlN:Fe nanorods so different charge states of substitutional FeAl should co-exist.

    Keywords: diversification of management, production diversification, financial and economic purposes of a diversification, technological purposes of ensuring flexibility of production

  • Comparative study of the catalytic activity Pt/C and PtхNi/C materials in the oxygen electroreduction

    The catalytic activity of Pt/C and PtxNi/C electrocatalysts prepared by  borohydride methode was studed. It was established that the specific activity  of fresh prepared Pt3,7Ni/C  catalyst  in oxygen  electroreduction  reaction is higher in compare with Pt/C material. After treatment of Pt3,7Ni/C material in the hot acid  nickel in the surface layers of nanoparticles was dissolved and the composition of nanoparticles was changed to Pt5,6Ni. The electrochemical surface area of the Pt5,6Ni catalyst and specific activity was slightly decreased after corrosion treatment. 

    Keywords: platinum electrocatalysts, corrosion stability of the nanoparticles, fuel cells, X-ray diffraction, borohydride synthesis

  • UV photodetector based on nanorods and zinc oxide films

    With the use of pulsed laser deposition and carbothermal synthesis а photosensitive structure on the basis of the Schottky barrier Au/ZnO(nanorods)/ZnO(film)/ZnO(nanorods)/Au was obtained. The parameters of the carbothermal method of synthesis of nanorods ZnO were optimized. Under directly applied bias of 7V current sensitivity of luminous flux for this photodetector is observed in the UV and visible regions of the spectrum, and is 0.14 A/W - for 325 nm and 0.18 A/W - to 405 nm, which means that this structure has the ability of potential applications in various fields for the control of UV radiation (for example, for the monitoring of solar UV radiation, control of UV radiation in air and disinfecting water devices).

    Keywords: ZnO nanorods, Schottky barrier, photodetector, photosensitivity

  • Modeling of MOSFET parameters in a wide temperature range

    The temperature dependencies of the main parameters of p-channel MOSFET model in a temperature range 20 ... 300 K are measured. The universal formal four-parametric model, which allows approximating all experimental temperature dependencies with the relative error less than 1 % is proposed. The model is intended for the MOSFETs which are applying in low-noise amplifiers of the radio-receiving devices of an optical and infrared range on astronomical satellites, radio telescopes and space observatories. The presented results can be used to simulate the temperature modes of MOSFET amplifiers in SPICE-type electronic simulators. The solution of this problem will predict uptime device when the temperature changes in the cases of emergency or extraordinary situations and also will allow optimizing the choice of refrigerant and increasing the reliability of the amplifier in the conditions of cryogenic temperatures.

    Keywords: MOSFET, MOSFET parameters, cryogenic temperature, parameters measurement, temperature dependencies

  • Raman spectroscopy as a method for structure analysis of individual carbon nanotubes

    In this paper a systematic study of individual single-walled and multi-walled carbon nanotubes was performed by Raman spectroscopy and high-resolution electron microscopy. We have presented the geometrical and electronic structure analysis on the examples of two tubes: individual single-walled and double-walled nanotubes. The role of different environmental effects and their influence on the final structure assignment are discussed. Moreover, we have shown that the Raman spectroscopy gives reliable estimations of the nanotube diameters and the conductivity. Given a non-destructible character of Raman spectroscopy, we may conclude that it is one of the most efficient methods for structure analysis of carbon nanotubes.

    Keywords: Carbon nanotubes, Raman spectroscopy, electron microscopy

  • The Electrically Active Impurities Inhomogeneous Distribution Influence on The Charge Carriers Transfer in Metal-semiconductor Contacts with Schottky Barrier

    The mathematical model and the simulation of metal-semiconductor contacts with Schottky barrier volt-ampere characteristics taking into account electrically active impurities inhomogeneous distribution in semiconductor are proposed in this work. The developed mathematical model takes into account quantum mechanical effects during the charge carriers transfer in metal-semiconductor junctions with Schottky barrier and allows forecasting their volt-ampere characteristics. The simulation results meet the experimental data from famous literary sources. The developed mathematical model can be used in computer aided design of integrated circuits elements.

    Keywords: Schottky diode, potential, Poisson equation, volt-ampere characteristic

  • Improvement of the quality of dark images

    Main disadvantages of a dark image are considered. Alternative algorithm of improving dark images is proposed.

    Keywords: Preliminary processing, digital image analysis, digital image improvement, Gaussian noise, dark images.

  • Evaluating of of fuel efficiency in the unified electric power station based on a combustion engine with alternating frequency rotation of shaft.

    The description of the flow sheet of unified electric power station of ship based on a combustion engine by alternating frequency rotation of shaft. The assessment of fuel profitability of such electric power station is given. In article materials of the state contract № 16.526.12.6016 on 11.10.2011 are used.

    Keywords: unified electric power station, explosion engine, synchro generator, synchro motor, converter

  • Analysis of the processes of foreign studies forestry road trains

    the analysis of foreign researches, which consist of processes of functioning timber lorries is given. Decrease transport expenses with minimization of empty run of timber lorries and formations of rational structure of this park has been proved.

    Keywords: timber lorries, functioning

  • Influence of the manganese nitrate surface phenomena characteristics on impregnating tantalum capacitor anode

    The influence of manganese nitrate impregnating solutions concentration and temperature dynamic viscosity, the wetting angle, interface “porous tantalum electrode - solution” free surface energy and the impregnation degree of porous tantalum anode was researched. A quantitative characteristic of manganese nitrate solution application on porous tantalum anode of solid-electrolyte capacitor during the process of impregnation was defined and work of adhesion and cohesion was calculated. Thus increasing of solution concentration above 42% wt brings to sharp growth of surface tension and so work of cohesion is increased but carriers impregnation is fallen. The most effective impregnation is realized at concentration 27% wt. This fact corresponds to best value of tantalum anode capacitor free surface energy. So using received data we are able to estimate optimal conditions of impregnation and wetting process by nitrate magnesium.  

    Keywords: manganese nitrate, manganese dioxide, limiting wetting angle, free surface energy

  • Flexible piezocomposites with mixed connectivity phases in the system

      Laboratory technology was developed to fabricate flexible piezocomposites with ferroelectric phase - polymers having signal reception factorv • gv 5000 • 10-15 m2 / N. The values of the given coefficient were achieved by switching from a probabilistic (spontaneous) percolation to a correlated one in the process of forming material. This made the production of 0-1–3 piezocomposites, in which a part of piezophase has 0 connectivity, and the other part – 1 connectivity possible. To improve the efficiency of piezocomposite polarization before their manufacturing the surface of piezophase particles, which were obtained by the partial destruction of the porous frameworks, was treated with coupling agent, which did not only improve the polymer adhesion to piezophase, but also allowed the removal of water from the particle surface. The latter effect reduced the value of interfacial conductivity, i.e. prevented the voltage drop of the polarizing field. Matching of polymer conductivity and piezoceramic particles by determining the optimal polarization temperature was carried out as well.  

    Keywords: piezocomposites, percolation, connectivity, electrophysical properties

  • Regularity and reliability is in the estimation of quality of public passenger transport

     Quality of services of public passenger transport depends on many indexes. Reliability and regularity is important indexes of quality of public passenger transport. The example calculation of reliability is considered. Conclusions on reliability and regularity of routes are done  

    Keywords: quality, public passenger transport, regularity, reliability

  • Convergence of the method of theoretical modeling X-ray absorption spectra for Ru XANES L 2,3-edges in the density functional theory (DFT) crystals as an example [Ru (NH3) 6 3 +

    The results of analysis of computational aspects of the method of obtaining the XANES spectra for Ru L2 ,3-edges by integrating the dipole transition matrix elements involving DFT. The convergence of the numerical integration procedure for the parameters used in the earlier papers, crystals as an example [Ru (NH3) 6] 3 +. More specifically, it is proved that it is possible to use a small area of ​​integration and big enough step between points, which helps to minimize the requirements for computing power and offers the prospect of using this method for the simulation of the XANES spectra in coordinated ruthenium catalysts for splitting water research in the field of solar energy.
    Keywords: RuLedge, XANES, DFT, density functional theory, X-ray absorption spectroscopy, geksoaminoruteny, Ru (NH3) 6.

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