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排序方式: 共有606条查询结果,搜索用时 15 毫秒
601.
Takahashi Jun Ishikawa Kyohhei Kawakami Kazuto Fujioka Masaaki 《Metallurgical and Materials Transactions A》2023,54(2):526-536
Metallurgical and Materials Transactions A - To elucidate the hardenability improvement mechanisms and hardenability-controlling factors in low-carbon (C) steels with the combined addition of... 相似文献
602.
603.
Chu-Wei Hsu Takuro Miyano Keisuke Awaya Masayuki Tsushida Kazuto Hatakeyama Michio Koinuma Shintaro Ida 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(12):2206552
Bandgap tunable lanthanum niobium oxynitride [LaNb2O7-xNx](1+x)− nanosheet is prepared by the delamination of a Ruddlesden−Popper phase perovskite oxynitride via ion−exchange and two−step intercalation processes. The lanthanum niobium oxynitride nanosheets have a homogeneous thickness of 1.6 nm and exhibit a variety of chromatic colors depending on the nitridation temperature of the parent-layered oxynitride. The bandgap energy of the nanosheets is determined by ultraviolet photoemission spectroscopy, Mott–Schottky, and photoelectrochemical measurements and is found to be tunable in the range of 2.03–2.63 eV. Furthermore, the oxide/oxynitride superlattice structures are fabricated by face−to−face stacking of 2D crystals using oxynitride [LaNb2O7-xNx](1+x)− and oxide [Ca2Nb3O10]− nanosheets as building blocks. Moreover, the superlattices-like restacked oxynitride/oxide nanosheets hybrid exhibits unique proton conductivity and dielectric properties strongly influenced by the oxynitride nanosheets and enhanced photocatalytic activity under visible light irradiation. 相似文献
604.
The paper proposes a method to select a power factor for an inverter of distributed power generation systems to keep appropriate voltage of a power system with the high penetration of inverter-interfaced generation. The increase of inverter-interfaced power sources, such as wind and photovoltaic power generation, arouses concerns on the voltage fluctuations in a power system. While constant power factor control of an inverter has been studied as a means to stabilize the voltage of a power system, there still remains room to improve the control. The proposed method in the paper selects the power factor based on the R/X ratio of the looking-back impedance into the interconnected power system. By normalizing the related variables, a general formula is derived for the power factor, and the resultant relationship between the apparent power and voltage of an inverter becomes identical irrespective of the R/X ratio with the control. Sample studies show that, by operating an inverter with the power factor, voltage fluctuations are effectively suppressed even for a power system with the high penetration of inverter-interfaced generation. 相似文献
605.
Dr. Yuma Shisaka Dr. Erika Sakakibara Dr. Kazuto Suzuki Dr. Joshua Kyle Stanfield Dr. Hiroki Onoda Garyo Ueda Miu Hatano Dr. Hiroshi Sugimoto Prof. Osami Shoji 《Chembiochem : a European journal of chemical biology》2022,23(14):e202200095
Tetraphenylporphyrin (TPP) is a symmetrically substituted synthetic porphyrin whose properties can be readily modified, providing it with significant advantages over naturally occurring porphyrins. Herein, we report the first example of a stable complex between a native biomolecule, the haemoprotein HasA, and TPP as well as its derivatives. The X-ray crystal structures of nine different HasA-TPP complexes were solved at high resolutions. HasA capturing TPP derivatives was also demonstrated to inhibit growth of the opportunistic pathogen Pseudomonas aeruginosa. Mutant variants of HasA binding FeTPP were shown to possess a different mode of coordination, permitting the cyclopropanation of styrene. 相似文献
606.
Anik Kumar Ghosh Swagato Sarkar Takuya Tsuda Soosang Chae André Knapp Mirko Nitschke Amit Das Sven Wießner Tobias A. F. König Andreas Fery 《Advanced functional materials》2023,33(23):2210172
Metal-semiconductor nanostructures in various configurations are extensively used in photodetection, photocatalysis, and photovoltaics. For photodetection purposes, the working principle is straightforward; on illumination, generated charge carriers in excess lead to a decrease in resistance. Notably, using an interconnected metal-semiconductor grating, it is observed and now reported an opposite response, an increase in the resistance. Such photoresistors are fabricated through wrinkle structuring and oblique angle material deposition methods. It is found that the controlled wrinkling leads to large-area 1D periodic structures with coexisting cracking perpendicular to the grating direction—such cracks are used as connections between the two-point contact measurement through the associated gold layer deposition. An enhanced current reduction is further observed on photoexcitation for an additional deposition of an amorphous titania layer. Subsequently, a discussion on the mechanisms and interaction between hot electron injection, charge carrier recombination, and thermalization is presented. Supported by numerical modeling, the angle-resolved plasmonic modes with the photoresistance can be correlated. The ease of layered deposition of the materials allows one to extend the studies on cavity-based structures with sandwiched titania layers as hotspots. This simple, scalable, and robust fabrication method thus promises an efficient routeway toward photosensor development in which plasmon-mediated hot electrons play a crucial role. 相似文献