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101.
102.
Latun T. S. Tsumarev Yu. A. Sheleg V. K. Bobritskiy S. M. Latun M. V. 《Russian Engineering Research》2022,42(11):1149-1153
Russian Engineering Research - The formulation of permanent joints is considered. To improve joint creation, resolution of their stress–state into components during the design stage is proposed. 相似文献
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Ana Iglesias-Juez Gian Luca Chiarello Gregory S. Patience M. Olga Guerrero-Prez 《加拿大化工杂志》2022,100(1):3-22
Although X-ray absorption spectroscopy (XAS) was conceived in the early 20th century, it took 60 years after the advent of synchrotrons for researchers to exploit its tremendous potential. Counterintuitively, researchers are now developing bench type polychromatic X-ray sources that are less brilliant to measure catalyst stability and work with toxic substances. XAS measures the absorption spectra of electrons that X-rays eject from the tightly bound core electrons to the continuum. The spectrum from 10 to 150 eV (kinetic energy of the photoelectrons) above the chemical potential—binding energy of core electrons—identifies oxidation state and band occupancy (X-ray absorption near edge structure, XANES), while higher energies in the spectrum relate to local atomic structure like coordination number and distance, Debye-Waller factor, and inner potential correction (extended X-ray absorption fine structure, EXAFS). Combining XAS with complementary spectroscopic techniques like Raman, Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance (EPR) elucidates the nature of the chemical bonds at the catalyst surface to better understand reaction mechanisms and intermediates. Because synchrotrons continue to be the light source of choice for most researchers, the number of articles Web of Science indexes per year has grown from 1000 in 1991 to 1700 in 2020. Material scientists and physical chemists publish an order of magnitude articles more than chemical engineers. Based on a bibliometric analysis, the research comprises five clusters centred around: electronic and optical properties, oxidation and hydrogenation catalysis, complementary analytical techniques like FTIR, nanoparticles and electrocatalysis, and iron, metals, and complexes. 相似文献
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The influence of various additives—including nanoparticles—on coal pitch is investigated, with a view to improving its properties. Surfactants facilitate the formation of coal-pitch products but have little effect on their properties. Materials that react with the pitch components may increase the yield and microstructure of pitch coke. Nanoparticles increase the yield of pitch coke and its aggregate strength. Additives are classified in terms of their effects on the pitch. 相似文献
107.
V. N. Gadalov S. G. Emel’yanov E. A. Filatov I. A. Makarova V. G. Sal’nikov 《Russian Engineering Research》2018,38(9):680-686
Structural, subeutectoidal structural, and tool steels are studied. Their boriding is considered. Equipment for electrolytic boriding and a modernized high-temperature casting crucible are presented. The conditions of electrolytic boriding are established. Shortcomings of electrolytic boriding are noted. 相似文献
108.
Gorkunov E. S. Povolotskaya A. M. Zadvorkin S. M. 《Russian Journal of Nondestructive Testing》2018,54(12):861-870
Russian Journal of Nondestructive Testing - Comparative analysis of the distribution of magnetic-induction vector components over the volume of a bulk homogeneous sample of 40Kh steel has been... 相似文献
109.
M. A. Elistratova D. S. Poloskin D. N. Goryachev I. B. Zakharova O. M. Sreseli 《Semiconductors》2018,52(8):1051-1055
Radiation stability of the nanoporous silicon under gamma irradiation was investigated. Changes in the properties of porous silicon under gamma irradiation were registered by measurements of photoluminescence spectra and Fourier-transform infrared (FTIR) spectroscopy. Besides the appearance of point defects and their subsequent oxidation, the significant differences were shown to be in the behavior of the porous silicon properties in comparison with that of bulk silicon apparently due to the quantum size nature of nanoporous silicon. 相似文献
110.
Mouloud Baik M. Hammoudi Y. Salhi S.K. Kirati 《International Journal of Hydrogen Energy》2018,43(6):3466-3474
In this work we present a scenario of wind and solar energy production and seasonal energy storage producing Hydrogen in Djanet (East-South of Algeria). In addition we suppose assume the use of a set of fuel cells which are connected to the grid to provide a supply of energy when needed afterwards. The aim of this primary study is giving an alternative solution for the electric production in Djanet, which is mainly based on diesel generator. For that we made an investigation to highlight the potential of renewable energy production in this region. To ascertain feasibility of one hybrid system, we made energetic assessment considering the real climatic conditions of Djanet. 相似文献