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961.
Nataliya A. Ivanova Dmitry D. Spasov Adelina A. Zasypkina Olga K. Alekseeva Elena V. Kukueva Ekaterina A. Vorobyeva Ekaterina S. Kudinova Ratibor G. Chumakov Pierre Millet Sergey A. Grigoriev 《International Journal of Hydrogen Energy》2021,46(34):18093-18106
We report on a comparative study of the performance level of H2/O2 PEM fuel cells in which the catalytic layers containing Pt nanoparticles were deposited on the microporous layer side of gas diffusion electrodes, using three different deposition techniques: (i) by magnetron sputtering, (ii) by impregnation followed by chemical reduction (using either ethylene glycol or hydrogen or sodium borohydride as reducing agent), and (iii) by spraying a catalytic ink (containing either Pt/C or bulk Pt particles). The microstructure and chemical composition of the different catalytic layers has been determined by SEM, TEM, XRD and XPS analysis. Their electrochemical surface areas have been determined by cyclic voltammetry. The i-V curves have been measured and compared. A durability stress test based on cycles of potential was used to assess the degradation rate of the different catalytic layers and to rank performance. 相似文献
962.
Nazym Akhanova Yerassyl Yerlanuly Didar Batryshev Timur Kulsartov Yevgeniy Chikhray Tlekkabul Ramazanov Ayfer Veziroglu Dmitry Schur Wanli Kang Maratbek Gabdullin 《International Journal of Hydrogen Energy》2021,46(10):7426-7431
In this work, the results of the hydrogen permeability study of a composite film-forming inhibitor are considered. Film-forming inhibitor consists of polyether urethane and synthesized fullerenes C60 and C70 in pure form. Two types of samples were used: uncoated and coated stainless steels with composite polyether urethane/fullerene varnish. The experimental work was based on the study of the dependence of the permeation reduction factor on the temperature in the reactor. For the coated sample, the minimum temperature was 623 K at which the deuterium flux was registered. Here we assume that at temperatures below 573 K the output pressure caused by the deuterium flow through the sample is less than 10?10 Pa. The rate of steady-state flow through a coated sample is significantly lower than for an uncoated one at temperatures 573–673 K. The deuterium penetration rates through the two samples increase and reach similar stationary values starting at 723 K. 相似文献
963.
Andrei I. Klyndyuk Michał Mosiałek Dmitry S. Kharitonov Ekaterina A. Chizhova Małgorzata Zimowska Robert P. Socha Anna Komenda 《International Journal of Hydrogen Energy》2021,46(32):16977-16988
Single- and double-doped YBa(Fe,Co,Cu)2O5+δ layered perovskites are prepared by solid state reaction method and their structural characteristics, thermal expansion coefficient, oxygen nonstoichiometry, electrical conductivity, and electrochemical performance are comparatively studied. The substitution of Co by Fe or/and Cu significantly improves thermal expansion properties as compared to undoped YBaCo2O5+δ. Electrochemical tests demonstrate the promising performance of synthesized materials as cathode materials at intermediate temperatures. Single doped YBaCuCoO5+δ cathodes reveal the lowest polarization resistance equal to 0.24 and 0.78 Ω cm2 at P(O2) P?1 = 0.2 at temperature of 800 and 700 °C, respectively. 相似文献
964.
Mazurova K. M. Dyakina Yu. I. Chudin E. A. Domovenko A. V. Makarov A. A. Pakhomov A. L. Vinokurov V. A. 《Chemistry and Technology of Fuels and Oils》2021,57(5):777-782
Chemistry and Technology of Fuels and Oils - When unstable gas condensate is analyzed using direct sample injection into a chromatograph, the design features and operating parameters of the... 相似文献
965.
Electronic skins (e-skins) have established themselves as a versatile technology to restore or enhance human perception, and potentially enable softer robotics. So far, the focus has been mostly on reproducing the traditional functions associated with human skin, such as, temperature, pressure, and chemical detection. New developments have also introduced nonstandard sensing capabilities like magnetic field detection, to spawn the field of magnetosensitive e-skins. Adding a supplementary information channel—an electronic sixth sense—allows humans to utilize the surrounding magnetic fields as stimuli for touchless interactions. Due to their vectorial nature, these stimuli can be used to track motion and orientation in 3D, opening the door to various kinds of gestural control for interactive devices. This approach to tracking provides an alternative or complement to optic-based systems, which usually rely on cameras or infrared emitters, that cannot easily capture fine motion when objects are far from the source or the line-of-sight is obtruded. Here, the background, fabrication techniques, and recent advances of this field are reviewed; covering important aspects like: directional perception, geomagnetic field detection, on-site conditioning, and multimodal approaches. The aim is to give the reader a general perspective and highlight some new avenues of research, toward artificial magnetoception. 相似文献
966.
Flexible Magnetoreceptor with Tunable Intrinsic Logic for On-Skin Touchless Human-Machine Interfaces
Pavlo Makushko Eduardo Sergio Oliveros Mata Gilbert Santiago Cañón Bermúdez Mariam Hassan Sara Laureti Christian Rinaldi Federico Fagiani Gianni Barucca Nataliia Schmidt Yevhen Zabila Tobias Kosub Rico Illing Oleksii Volkov Igor Vladymyrskyi Jürgen Fassbender Manfred Albrecht Gaspare Varvaro Denys Makarov 《Advanced functional materials》2021,31(25):2101089
Artificial magnetoception is a new and yet to be explored path for humans to interact with the surroundings. This technology is enabled by thin film magnetic field sensors embedded in a soft and flexible format to constitute magnetosensitive electronic skins (e-skins). Being limited by the sensitivity to in-plane magnetic fields, magnetosensitive e-skins are restricted to basic proximity and angle sensing and are not used as switches or logic elements of interactive wearable electronics. Here, a novel magnetoreceptive platform for on-skin touchless interactive electronics based on flexible spin valve switches with sensitivity to out-of-plane magnetic fields is demonstrated. The technology relies on all-metal Co/Pd-based spin valves with a synthetic antiferromagnet possessing perpendicular magnetic anisotropy. The flexible magnetoreceptors act as logic elements, namely momentary and permanent (latching) switches. The switches maintain their performance even upon bending to a radius of less than 3.5 mm and withstand repetitive bending for hundreds of cycles. Here, flexible switches are integrated in on-skin interactive electronics and their performance as touchless human-machine interfaces is demonstrated, which are intuitive to use, energy efficient, and insensitive to external magnetic disturbances. This technology offers qualitatively new functionalities for electronic skins and paves the way towards full-fledged on-skin touchless interactive electronics. 相似文献
967.
Igor P. Koskin Christina S. Becker Alina A. Sonina Vasiliy A. Trukhanov Nikita A. Shumilov Anatoly D. Kuimov Yuliya S. Zhuravleva Yuliya O. Kiseleva Inna K. Shundrina Peter S. Sherin Dmitry Yu. Paraschuk Maxim S. Kazantsev 《Advanced functional materials》2021,31(48):2104638
Linearly conjugated oligomers attract ever-growing attention as promising systems for organic optoelectronics because of their inherent lucky combination of high charge mobility and bright luminescence. Among them, furan-phenylene co-oligomers (FPCOs) are distinguished by outstanding solubility, very bright luminescence, and good hole-transport properties; however, furan-containing organic semiconductors generally lack electron transport, which makes it impossible to utilize them in efficient light-emitting electronic devices, specifically, ambipolar light-emitting transistors. In this work, 1,4-bis(5-phenylfuran-2-yl)benzene (FP5) derivatives are synthesized with the fully/partially fluorinated central and edge phenyl rings. It is shown that the selective fluorination of FPCOs lowers the energies of frontier molecular orbitals, maintaining the bandgap, solubility, and bright luminescence, dramatically improves the photostability, tunes the π-π stacked packing, and allows the first realization of electron transport in FPCOs. It is found that selectively fluorinated 2,2′-(2,3,5,6-tetrafluoro-1,4-phenylene)bis[5-(3,5-difluorophenyl)furan] demonstrates well-balanced ambipolar charge transport and efficient electroluminescence in an organic light-emitting transistor (OLET) with external quantum and luminous efficiencies as high as 0.63% and 5 cdA−1, respectively, which are among the best reported for OLETs. The findings show that “smart” fluorination is a powerful tool to fine-tune the stability and performance of linearly conjugated small molecules for organic optoelectronics. 相似文献
968.
Gennady Vasiliev Irina Chadaeva Dmitry Rasskazov Petr Ponomarenko Ekaterina Sharypova Irina Drachkova Anton Bogomolov Ludmila Savinkova Mikhail Ponomarenko Nikolay Kolchanov Alexander Osadchuk Dmitry Oshchepkov Ludmila Osadchuk 《International journal of molecular sciences》2021,22(5)
Earlier, after our bioinformatic analysis of single-nucleotide polymorphisms of TATA-binding protein-binding sites within gene promoters on the human Y chromosome, we suggested that human reproductive potential diminishes during self-domestication. Here, we implemented bioinformatics models of human diseases using animal in vivo genome-wide RNA-Seq data to compare the effect of co-directed changes in the expression of orthologous genes on human reproductive potential and during the divergence of domestic and wild animals from their nearest common ancestor (NCA). For example, serotonin receptor 3A (HTR3A) deficiency contributes to sudden death in pregnancy, consistently with Htr3a underexpression in guinea pigs (Cavia porcellus) during their divergence from their NCA with cavy (C. aperea). Overall, 25 and three differentially expressed genes (hereinafter, DEGs) in domestic animals versus 11 and 17 DEGs in wild animals show the direction consistent with human orthologous gene-markers of reduced and increased reproductive potential. This indicates a reliable association between DEGs in domestic animals and human orthologous genes reducing reproductive potential (Pearson’s χ2 test p < 0.001, Fisher’s exact test p < 0.05, binomial distribution p < 0.0001), whereas DEGs in wild animals uniformly match human orthologous genes decreasing and increasing human reproductive potential (p > 0.1; binomial distribution), thus enforcing the norm (wild type). 相似文献
969.
Fibre Chemistry - Problems of modeling and prediction of deformation and relaxation processes of polymer yarn products are studied. Mathematical models of these processes that allow prediction of... 相似文献
970.
Alexander M. Demin Aleksei I. Maksimovskikh Alexander V. Mekhaev Dmitry K. Kuznetsov Artyom S. Minin Alexandra G. Pershina Mikhail A. Uimin Vladimir Ya Shur Victor P. Krasnov 《Ceramics International》2021,47(16):23078-23087
The high efficiency of using N-(phosphonomethyl)iminodiacetic acid (PMIDA) as a surfactant for formation of a silica coating on Fe3O4 magnetic nanoparticles (MNPs) with a large surface area has been demonstrated. The coating of PMIDA-stabilized MNPs with silica and their further APS-functionalization significantly increased the specific area (up to 203 m2 g?1) and the number of amino groups (up to 1.12 mmol/g) grafted on their surface compared to nanomaterials synthesized without preliminary SiO2-coating. The comparative study of the peptide modification efficiency, using as an example pH-low insertion peptide (pHLIP), of MNPs coated with 3-aminopropylsilane (APS) or SiO2/APS was carried out. It has been shown that silica coating of PMIDA-stabilized MNPs leads to a significant increase in the degree of immobilization of the peptide (up to 22 μmol per g of MNPs). Comprehensive characterization of the obtained materials at each stage of the synthesis was carried out using scanning electron microscopy (SEM), energy dispersive X-ray fluorescence spectroscopy (EDX), BET analysis, ATR Fourier transformed infrared spectroscopy (FTIR), termogravimetric analysis (TGA), CHN-elemental analysis, dynamic light scattering (DLS), and vibrating sample magnetometry (VSM). The proposed approach to applying SiO2-coating of MNPs can be useful for design of new materials for biomedical and chemical purposes. 相似文献