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排序方式: 共有3513条查询结果,搜索用时 78 毫秒
1.
Thermal barrier coatings (TBCs) are used to protect the hot sections of gas turbine engines and airplane engines. A TBC system comprises a substrate, bond coat, and TBC topcoat. The development of an accurate method for determining the Young’s modulus and Poisson’s ratio of TBC using a multilayered specimen is of importance. In this study, we applied the bending theory of a laminated plate to a three-layered material and proposed models to determine the Young’s modulus and Poisson’s ratio of the TBC layer using the bending strain of the TBC system specimen. Three methods were developed by utilizing (i) the coating biaxial strain, (ii) substrate biaxial strain, or (iii) coating and substrate biaxial strains. Subsequently, we determined appropriate dimensions of the specimen and span by using three-dimensional finite element analysis, and numerically verified the usefulness of the three proposed methods. However, the Young’s modulus and Poisson’s ratio determined using the multilayered specimen with a substrate are sensitive to experimental errors. Therefore, we evaluated the sensitivity of the three proposed methods to experimental error, and we determined the most insensitive method among them. Finally, we experimentally demonstrated the usefulness of this method. 相似文献
2.
Hideo Yamauchi Junichi Ikejiri Fumio Sato Hiroyuki Oshita Tsuyoshi Honma Takayuki Komatsu 《Journal of the American Ceramic Society》2019,102(11):6658-6667
In recent years, the expansion of demand for lithium ion batteries has resulted in soaring prices of the constituent resources. From the viewpoint of safety, studies on all-solid-state batteries are actively being carried out. In this study, we succeeded in driving all-solid-state batteries derived from nontoxic oxide glasses at room temperature without requiring scarce resources such as lithium and cobalt. The main structure of the ceramic batteries with a simple structure in which Na2FeP2O7 crystallized glass and β″-alumina solid solution are joined by pressureless cofiring at 550°C. During the crystallization of Na2O-Fe2O3-P2O5 glass, fusion with the β″-alumina solid solution is achieved. Reversible charge and discharge of 80 mAh/g were achieved at room temperature. It is not necessary to apply pressure during cell preparation or the use of the batteries. Furthermore, the strong junction at the cathode and electrolyte interface does not peel off during charge and discharge over a long period of 623 cycles. Ex situ X-ray photoelectron spectroscopy revealed partial Fe4+ induction and a reversible charge and discharge reaction even after overcharging to 9 V. It was demonstrated that Na2FeP2O7 is very stable against overcharging to 9 V. 相似文献
3.
Li Minggang Matsuura Hiroyuki Tsukihashi Fumitaka 《Metallurgical and Materials Transactions B》2019,50(6):2993-3001
Metallurgical and Materials Transactions B - Evolution of TiS in composition and morphology as well as the change in size distribution of TiS and TiN in Fe-40 masspctNi austenitic alloy during... 相似文献
4.
5.
Zou Xiaodong Matsuura Hiroyuki Wang Cong 《Metallurgical and Materials Transactions B》2019,50(3):1134-1138
Metallurgical and Materials Transactions B - The evolution behaviors of MnS inclusions during 1473 K heating have been systematically investigated for EH36 shipbuilding steel with Zr addition. It... 相似文献
6.
Shoji Eita Takahashi Ryuji Isogai Shosei Ito Naoto Kubo Masaki Tsukada Takao Fukuyama Hiroyuki 《Metallurgical and Materials Transactions B》2019,50(5):2454-2458
Metallurgical and Materials Transactions B - Normal spectral emissivity of molten Cu-Fe alloy with different compositions was measured at the wavelength of 807 nm using an electromagnetic... 相似文献
7.
Dr. Xiaoyun Deng Dr. Akiko Hatori Dr. Zhen Chen Dr. Katsushi Kumata Dr. Tuo Shao Dr. Xiaofei Zhang Dr. Tomoteru Yamasaki Dr. Kuan Hu Dr. Qingzhen Yu Dr. Longle Ma Dr. Gangqiang Wang Dr. Lu Wang Prof. Dr. Yihan Shao Prof. Dr. Lee Josephson Prof. Dr. Shaofa Sun Prof. Dr. Ming-Rong Zhang Prof. Dr. Steven Liang 《ChemMedChem》2019,14(3):303-309
Muscarinic acetylcholine receptors (mAChRs) have five distinct subunits (M1–M5) and are involved in the action of the neurotransmitter acetylcholine in the central and peripheral nervous system. Attributed to the promising clinical efficacy of xanomeline, an M1/M4-preferring agonist, in patients of schizophrenia and Alzheimer's disease, M1- or M4-selective mAChR modulators have been developed that target the topographically distinct allosteric sites. Herein we report the synthesis and preliminary evaluation of 11C-labeled positron emission tomography (PET) ligands based on a validated M4R positive allosteric modulator VU0467485 (AZ13713945) to facilitate drug discovery. [11C]VU0467485 and two other ligands were prepared in high radiochemical yields (>30 %, decay-corrected) with high radiochemical purity (>99 %) and high molar activity (>74 GBq μmol−1). In vitro autoradiography studies indicated that these three ligands possess moderate-to-high in vitro specific binding to M4R. Nevertheless, further physiochemical property optimization is necessary to overcome the challenges associated with limited brain permeability. 相似文献
8.
Tomoko Okuyama Jun Shirakawa Kazuki Tajima Yoko Ino Heidrun Vethe Yu Togashi Mayu Kyohara Ryota Inoue Daisuke Miyashita Jinghe Li Nozomi Goto Taiga Ichikawa Shingo Yamasaki Haruka Ohnuma Rie Takayanagi Yayoi Kimura Hisashi Hirano Yasuo Terauchi 《International journal of molecular sciences》2020,21(21)
9.
Ireneusz Buganski Kotoba Toyonaga Hiroyuki Takakura Tsunetomo Yamada Marc de Boissieu Olivier Perez 《Materials Science & Technology》2020,36(9):989-995
ABSTRACTWe report a successful growth of the ZnMgHf F-type icosahedral quasicrystal in the form of faceted single grains. By varying the heat treatment parameters we were able to obtain single crystals with a quality suitable for a single crystal X-ray diffraction which was conducted in a synchrotron facility. Ab initio structure solution by a charge flipping algorithm manifests the existence of two types of Bergman clusters. Clusters are differentiated by the preferential occupation of the high-symmetry positions by hafnium in a rhombic triacontahedron, being the outer shell of the atomic cluster.This paper is part of a Thematic Issue on The Crystallographic Aspects of Metallic Alloys. 相似文献
10.