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111.
Seki S Kobayashi Y Miyashiro H Ohno Y Usami A Mita Y Watanabe M Terada N 《Chemical communications (Cambridge, England)》2006,(5):544-545
For the purpose of realizing high-voltage, high-capacity, long-life and safe rechargeable batteries, a lithium secondary battery that uses high-voltage stable ZrO2-coated LiCoO2 cathode powder and a nonvolatile high-safety room temperature ionic liquid was fabricated. 相似文献
112.
A clay-like conductive material comprising polyaniline-loaded carbon black particles and an ethyleneoxide-substituted imidazolium iodide was prepared. The material was sandwiched between dye-coated porous TiO2 and counter-electrode to form a solid-state dye-sensitized solar cell, which works with overall conversion efficiencies of 3.48% and 4.07% for AM 1.5, 100 mW cm(-2) and 23 mW cm(-2) irradiation, respectively. 相似文献
113.
Masaaki Hori Harushi Mori Shigeki Aoki Osamu Abe Tomohiko Masumoto Satoshi Kunimatsu Kuni Ohtomo Hiroyuki Kabasawa Nobuyuki Shiraga Tsutomu Araki 《Magnetic resonance imaging》2010
Object
Although three-dimensional (3D), high-spatial resolution susceptibility-weighted imaging (SWI) appears to be valuable in the evaluation of central nervous system gliomas, several evaluation methods are proposed in the literature. The purpose of this study was to evaluate the use of 3D SWI for grading intracranial gliomas with various analysis methods.Materials and Methods
Twenty-three patients suspected of having gliomas participated in this study. SWI was performed in addition to conventional MR sequences. In 15 cases, post-gadolinium enhanced SWI was also obtained. Imaging evaluation criteria were conventional grade, hypointensity ratio in the tumor-dominant structure of hypointensity on SWI (hemorrhage or vascular structure) and presence of abnormal enhancement surrounding the tumor.Results
Mean grading scores of conventional grade showed no statistically significant difference among WHO grades. Mean grading scores of hypointensity ratios in the tumor were higher for WHO Grades 3 and 4 than for lower grade tumors (P=.05, Mann–Whitney U test). Hemorrhagic foci were more frequently seen in the higher grade tumor. Post-contrast susceptibility-weighted images of five of 11 WHO Grade 3 and 4 cases showed bright enhancement surrounding the tumor, suggesting a breakdown of the blood–brain barrier.Conclusions
SWI at 3 T may be a useful method to analyze the structural characteristics of gliomas and to evaluate pathology in vivo. Assessment of hypointensity ratios in the glioma was the most preferable method in grading glioma. However, more studies, specifically concerning a suitable method for image analysis, are needed to establish SWI at 3 T as a useful tool in clinical routine. 相似文献114.
115.
For a space X, X2 denotes the collection of all non-empty closed sets of X with the Vietoris topology, and K(X) denotes the collection of all non-empty compact sets of X with the subspace topology of X2. The following are known:
- •
- ω2 is not normal, where ω denotes the discrete space of countably infinite cardinality.
- •
- For every non-zero ordinal γ with the usual order topology, K(γ) is normal iff whenever cf γ is uncountable.
- (1)
- ω2 is strongly zero-dimensional.
- (2)
- K(γ) is strongly zero-dimensional, for every non-zero ordinal γ.
116.
Nobuyuki Kemoto 《Topology and its Applications》2010,157(15):2446-2447
We correct the proof of Theorem 8 in “Normality and countable paracompactness of hyperspaces of ordinals” [Topology Appl. 154 (2007) 358-362]. 相似文献
117.
Among Professor Kiyosi Itô’s achievements, there is the Itô–Nisio theorem, a completely general theorem relative to the Fourier series decomposition of Brownian motion. In this paper, some of its applications will be reviewed, and new applications to 1-soliton solutions to the Korteweg–de Vries (KdV for short) equation and Eulerian polynomials will be given. 相似文献
118.
Yoshiki Wada Nobuyuki Matsushita Masahiro Yamashita 《Molecular Crystals and Liquid Crystals》2013,570(1):891-896
Abstract Photo-induced absorption (PA) spectra of [Pt (en)2] [Pt (en)2X2] (SO2)2. 6H2O (X=Cl and Br) have been measured. Large excitation photon energy dependent changes were found in the features of the PA spectra. The excitation photon energy dependences are considered to be due to the difference between the relaxation processes of the charge transfer excitons and those of the higher energy excited states. Several new PA bands have been found. 相似文献
119.
Yuto Suzuki Mario Gutirrez Senri Tanaka Eduardo Gomez Norimitsu Tohnai Nobuhiro Yasuda Nobuyuki Matubayasi Abderrazzak Douhal Ichiro Hisaki 《Chemical science》2021,12(28):9607
The library of isostructural porous frameworks enables a systematic survey to optimize the structure and functionality of porous materials. In contrary to metal–organic frameworks (MOFs) and covalent organic frameworks (COFs), a handful of isostructural frameworks have been reported for hydrogen-bonded organic frameworks (HOFs) due to the weakness of the bonds. Herein, we provide a rule-of-thumb to develop isostructural HOFs, where we demonstrate the construction of the third and fourth generation of isostructural HAT-based HOFs (TolHAT-1 and ThiaHAT-1) by considering three important structural factors, that are (1) directional H-bonding, (2) shape-fitted docking of the HAT core, and (3) modulation of peripheral moieties. Their structural and photo-physical properties including HCl vapor detection are presented. Moreover, TolHAT-1, ThiaHAT-1, and other isostructural HOFs (CPHAT-1 and CBPHAT-1) were thoroughly compared from the viewpoints of structures and properties. Importantly, molecular dynamics (MD) simulation proves to be rationally capable of evaluating the stability of isostructural HOFs. These results can accelerate the development of various isostructural molecular porous materials.The library of isostructural porous frameworks enables a systematic survey to optimize the structure and functionality of porous materials. 相似文献
120.
Transverse wave generation mechanism in rotating detonation 总被引:2,自引:0,他引:2
Yuho Uemura A. Koichi Hayashi Makoto Asahara Nobuyuki Tsuboi Eisuke Yamada 《Proceedings of the Combustion Institute》2013,34(2):1981-1989
Detonation engines are expected to be included in a number of aerospace thrusters in the future. Several types of detonation engines are currently under examination, including the rotating detonation engine (RDE). Although the RDE has been explored experimentally, its rotating detonation propagation mechanism is not well understood. This paper clarifies the detonation mechanism and dynamics of the RDE by 2D and 3D simulation using compressible Euler equations with a full chemical reaction mechanism of H2/O2 and H2/Air, especially from the triple-point and transverse detonation points of view. A total variation diminishing (TVD) scheme is used for the mixture of H2/Air, and an advection upwind splitting method difference vector (AUSMDV) scheme is used for the mixture of H2/O2. The use of an AUSMDV scheme provides a much clearer detonation structure than does the TVD scheme. We focus on the complex interaction mechanism of the detonation front and burned mixture gases. We found out that at this interaction point, an unreacted gas pocket appears and ignites periodically to generate transverse waves at the detonation front and maintain detonation propagation. 相似文献