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141.
Dongshin Myung Yumin Lee Jaeyeon Lee Hak Ki Yu Jong‐Lam Lee Jeong Min Baik Woong Kim Myung Hwa Kim 《固体物理学:研究快报》2010,4(12):365-367
We present the synthesis of highly crystalline metallic rhenium trioxide (ReO3) nanowires via a simple physical vapor transport at 300 °C for the first time. Based on HRTEM, the ReO3 nanowires exhibit a core of perfect cubic perovskite‐type single crystal structure with a shell of thin amorphous and disordered structures of less than 2 nm in the near surface layers. Possibly this is due to proton intercalation induced by the surface reaction of single crystal ReO3 with water.
142.
Ki Hyeon Kim Masahiro Yamaguchi Hironori Orikasa Takashi Kyotani 《Solid State Communications》2006,140(11-12):491-494
The radio frequency characteristics of Permalloy nanorods’ array have been examined by coplanar waveguide (CPW) cell. The Permalloy nanorods’ array was grown in anodic aluminum oxide porous templates with a diameter of 20 nm. As the Permalloy nanorods’ array was placed on CPW, the characteristic impedances of the CPW were changed from 50 to at 1 GHz. The magnitude of inductance was decreased from 3 GHz and the capacitance was increased up to twice in comparison with that of CPW. The signal attenuations were abruptly increased over 1 GHz. The propagation wavelengths due to the insertion of Permalloy nanorods’ array were decreased about 30% at 1 GHz in comparison with that of CPW without magnetic materials. 相似文献
143.
Chang‐Hyuk Choi Hong‐Tae Kim Jung‐Yoon Choe Seong‐Kyu Kim Gi‐Whan Choi SangHoon Jheon Jong‐Ki Kim 《Journal of synchrotron radiation》2010,17(3):393-399
In vivo microstructures of the affected feet of collagen‐induced arthritic (CIA) mice were examined using a high‐resolution synchrotron radiation (SR) X‐ray refraction technique with a polychromatic beam issued from a bending magnet. The CIA models were obtained from six‐week‐old DBA/1J mice that were immunized with bovine type II collagen and grouped as grades 0–3 according to a clinical scoring for the severity of arthritis. An X‐ray shadow of a specimen was converted into a visual image on the surface of a CdWO4 scintillator that was magnified using a microscopic objective lens before being captured with a digital charge‐coupled‐device camera. Various changes in the joint microstructure, including cartilage destruction, periosteal born formation, articular bone thinning and erosion, marrow invasion by pannus progression, and widening joint space, were clearly identified at each level of arthritis severity with an equivalent pixel size of 2.7 µm. These high‐resolution features of destruction in the CIA models have not previously been available from any other conventional imaging modalities except histological light microscopy. However, thickening of the synovial membrane was not resolved in composite images by the SR refraction imaging method. In conclusion, in vivo SR X‐ray microscopic imaging may have potential as a diagnostic tool in small animals that does not require a histochemical preparation stage in examining microstructural changes in joints affected with arthritis. The findings from the SR images are comparable with standard histopathology findings. 相似文献
144.
Nishimura K Browder TE Adachi I Aihara H Arinstein K Aushev T Bakich AM Balagura V Barberio E Belous K Bhardwaj V Bischofberger M Bondar A Bozek A Bračko M Chang MC Chao Y Chen A Chen KF Chen P Cheon BG Chiang CC Cho IS Choi Y Dalseno J Danilov M Doležal Z Drutskoy A Eidelman S Gabyshev N Golob B Ha H Haba J Hara T Hayasaka K Hayashii H Horii Y Hoshi Y Hou WS Hyun HJ Iijima T Inami K Itoh R Iwabuchi M Iwasaki Y Joshi NJ Julius T Kang JH Kapusta P Kawai H Kawasaki T Kichimi H Kiesling C Kim HJ 《Physical review letters》2010,105(19):191803
We report a first measurement of inclusive B→Xsη decays, where Xs is a charmless state with unit strangeness. The measurement is based on a pseudoinclusive reconstruction technique and uses a sample of 657×10(6)BB pairs accumulated with the Belle detector at the KEKB e+e- collider. For MXs < 2.6 GeV/c2, we measure a branching fraction of [26.1±3.0(stat)-2.1+1.9(syst)-7.1+4.0(model)]×10(-5) and a direct CP asymmetry of ACP=-0.13±0.04-0.03+0.02. Over half of the signal occurs in the range MXs > 1.8 GeV/c2. 相似文献
145.
Chul Ki Ko 《Journal of Mathematical Analysis and Applications》2010,369(1):164-214
Furuichi, Yanagi and Kuriyama gave three conjectures of trace inequalities on the Wigner-Yanase-Dyson skew information and a generalized Wigner-Yanase skew information (Furuichi et al. (2009) [1]) and Yanagi found a counterexample showing that two of the three conjectures don't hold (Yanagi (2010) [6]). In this note, we show that the last conjecture does not hold in general. In addition, we show that in the case of 2×2 matrices the conjecture is true. 相似文献
146.
We investigated the effects of the alignment and ordering of pi-conjugated perfluorinated dendrimers containing pyrene moieties in their cores on their photoluminescence (PL) properties. The pyrene molecules are stacked in columns surrounded by aromatic and semifluorinated tails, which can be conjugated and act as chromophores. Polarized light microscopy (PLM), cross-sectional scanning electron microscopy (SEM), and atomic force microscopy (AFM) results show that variation of the cooling rate of the dendrimers produces variation in their orientation and ordering: Slow cooling (approximately <0.5 degrees C/min) of the isotropic melt in a sandwich glass cell results in a high degree of ordering and the vertical alignment of the columns on the substrate, in which the stacked pyrene molecules are oriented parallel to the surface over large areas. In contrast, rapid cooling (approximately >10 degrees C/min) leads to the planar alignment of the columns with significant disorder on the same substrate. UV-vis, PL, SEM, and AFM results show that the quenched columns with a planar orientation produce a broad emission band and a second weak shoulder, which indicates the presence of isolated molecules. However, the high degree of ordering of the columns with a vertical alignment produces a red-shift in the PL spectrum, with very few isolated molecules. By comparing two films with different alignments but similar ordering, we show that the ordering of this material has a greater influence on the PL spectrum than the alignment. This effect of the ordering of the columns was further verified by comparing the optical properties of the isolated dendrimers with those of small pi-conjugated molecules in solution and solid films. 相似文献
147.
Choon Ki Ahn 《Nonlinear Analysis: Hybrid Systems》2010,4(1):16-24
In this paper, we propose a new fuzzy delayed output feedback synchronization (FDOFS) method for time-delayed chaotic systems. Based on Lyapunov–Krasovskii theory, T–S fuzzy model, and delayed feedback control scheme, the FDOFS controller is designed and an analytic expression of the controller is shown. The proposed controller can guarantee asymptotical synchronization of both drive and response systems. The FDOFS controller can be obtained by solving the linear matrix inequality (LMI) problem. A numerical example for time-delayed Lorenz system is presented to demonstrate the validity of the proposed FDOFS method. 相似文献
148.
149.
This paper we investigate a comparison theorem and monotone mehtod for the construction of minimal and maximal solutions of the following int–volterra integral equation] 相似文献
150.
Sanghan Lee Wooyoung Jin Su Hwan Kim Se Hun Joo Gyutae Nam Pilgun Oh Young‐Ki Kim Sang Kyu Kwak Jaephil Cho 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(31):10588-10595
Oxygen vacancies (OV) are native defects in transition metal (TM) oxides and their presence has a critical effect on the physicochemical properties of the oxide. Metal oxides are commonly used in lithium‐ion battery (LIB) cathodes and there is still a lack of understanding of the role of OVs in LIB research field. Here, we report on the behavior of OVs in a single‐crystal LIB cathode during the non‐equilibrium states of charge and discharge. We found that microcrack evolution in a single crystal occurs due to OV condensation in specific crystallographic orientations generated by the continuous migration of OVs and TM ions. Moreover, understanding the effects of the presence and diffusion of OVs in metal oxides enables the elucidation of most of the conventional mechanisms of capacity fading in LIBs and provides new insights for new electrochemical applications. 相似文献