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81.
从理论和实验上研究了红绿荧光强度反转现象。实验测量发现Er(0.5)Yb(9.5)∶FOV纳米相氟氧化物玻璃陶瓷存在强的红绿荧光强度反转现象,实验测量得到其红绿荧光强度反转动态范围为877,同时计算了Er(0.5)Yb(9.5)∶FOV的所有基础光谱参量,建立了对系统所有稀土离子能级的动力学过程进行数值模拟计算的理论基础。 相似文献
82.
This paper introduces consumption externalities into an endogenous growth model of common capital accumulation and characterizes
balanced growth equilibria. Contrary to the standard argument in previous studies, we show that the growth rate in a feedback
Nash equilibrium can be higher than that in an open-loop Nash equilibrium if agents strongly admire the consumption of others.
This result is irrelevant to whether preferences exhibit “keeping up with the Joneses” or “running away from the Joneses”. 相似文献
83.
Analyzing the crystalline structure of α- and β-rhombohedral boron as an approximant structure of a quasicrystal, atomic structures of two unit cells (prolate and oblate rhombohedra) of icosahedral quasicrystal are constructed. According to molecular orbital calculation, a neutral B 12 H 12 icosahedral cluster is distorted to a cubic or rhombohedral type by the Jahn–Teller effect. The distortion of B 12 in the β-rhombohedral boron and K2B12H12 has the same sign as the lowest energy distortion in the calculation. Among the α-rhombohedral type structures, the distortion of B12 is correlated with the rhombohedral axis angle, and the angle is the closest to the icosahedral angle for B6O and the distortion is the smallest for B–C. A meta-stable phase has been found on the way towards crystallization of amorphous B–C films. 相似文献
84.
M. Hori A. Sótér D. Barna A. Dax R. S. Hayano S. Friedreich B. Juhász T. Pask E. Widmann D. Horváth L. Venturelli N. Zurlo 《Few-Body Systems》2013,54(7-10):917-922
The ASACUSA collaboration of CERN has recently irradiated antiprotonic helium atoms with two counter-propagating laser beams. This excited some non-linear two-photon transitions of the antiproton at the deep UV wavelengths λ = 139.8–197.0 nm. The counterpropagating geometry of the laser beams reduced the thermal Doppler broadening of the observed resonances. Their narrow spectral lines allowed the measurement of three transition frequencies with fractional precisions of 2.3–5 parts in 109. By comparing the results with three-body QED calculations, the antiproton-to-electron mass ratio was derived as 1836.1526736(23). 相似文献
85.
Kuroda N Torii HA Shibata M Nagata Y Barna D Hori M Horváth D Mohri A Eades J Komaki K Yamazaki Y 《Physical review letters》2008,100(20):203402
We report here the radial compression of a large number of antiprotons ( approximately 5 x 10(5)) in a strong magnetic field under ultrahigh vacuum conditions by applying a rotating electric field. Compression without any resonant structures was demonstrated for a range of frequencies from the sideband frequency of 200 kHz to more than 1000 kHz. The radial compression achieved is a key technique for synthesizing and manipulating antihydrogen atoms and antiprotonic atoms. 相似文献
86.
Naofumi Nishida Yuki Hori Akane Yamauchi Hazuki Fujiwara Makoto Sakurai Yuya Fujiwara Shin-ichi Honda Shunjiro Fujii Hiroyuki A. Sakaue Daiji Kato Tomohiro Yamaguchi Koji Ishibashi Toshifumi Terui Kuei-Yi Lee 《X射线光谱测定》2020,49(1):99-103
Interaction of highly charged ions (HCIs) with surfaces produce various specific phenomena as a consequence of the potential energy that HCI possesses. In the present study, we have observed photon emission, structural, magnetic, and electronic modification on various carbon-based materials such as carbon nanotube by the impact of HCIs using an electron beam ion source named Kobe EBIS installed at the Kobe University. In order to study the potential effect, HCIs of Arq+ (q = 6–16) with the intensity of 0.1–1 nA are projected on the surface with a constant kinetic energy (16 keV). For photon emission measurements, we observed spatial and spectral distribution of visible light emission from the surface during irradiation with HCIs. On the other hand, the structural modification of multi-walled carbon nanotubes (MWCNTs) irradiated with HCIs has been analyzed using a transmission electron microscopy and Raman spectroscopy. Irradiation effects on the resistivity of single MWCNT supported on micrometer scale bridge pattern were also measured. We have also measured magnetic structure of highly oriented pyrolytic graphite irradiated with HCIs using electron spin resonance at low temperature. At the present paper, we will review our recent experimental results on the interaction of HCI with various carbon-based materials. 相似文献
87.
Ahmad Ahmeda Naser Abbasi Hori Ghaneialvar Mohammad Mahdi Zangeneh Akram Zangeneh 《应用有机金属化学》2020,34(4):e5480
The aim of the study was the rapid green synthesis of titanium nanoparticles using the aqueous extract of Falcaria vulgaris leaves (TiNPs@FV) and exploring their antioxidant, cytotoxicity, antifungal, antibacterial, and cutaneous wound healing activities under in vitro and in vivo condition. These nanoparticles were characterized by UV-Vis, Fourier transform-infrared(FT-IR), X-ray diffraction XRD), field emission-scanning electron microscopy FE-SEM), and transmission electron microscopy TEM) analyses. The synthesized TiNPs@FV had great cell viability on human umbilical vein endothelial cells and indicted this method was nontoxic. DPPH (2,2-diphenyl-1-picrylhydrazyl) test revealed similar antioxidant potentials for F. vulgaris, TiNPs@FV, and butylated hydroxytoluene. All data of antibacterial, antifungal, and cutaneous wound healing tests were analyzed by SPSS 22 software. In the antimicrobial part of this study, TiNPs@FV indicated higher antifungal and antibacterial effects than all standard antibiotics (p ≤ 0.01). Minimal inhibitory concentration (MIC) and minimal fungicidal concentration of TiNPs@FV against all fungi were at 2–4 mg/mL and 2-8 mg/mL ranges, respectively. But, MIC and minimal bactericidal concentration of TiNPs@FV against all bacteria were at 2-8 mg/mL and 2-16 mg/mL ranges, respectively. In the part of cutaneous wound healing, use of TiNPs@FV ointment significantly (p ≤ 0.01) raised the wound contracture, vessel, hydroxyl proline, hexuronic acid, hexosamine, fibrocyte, and fibrocytes/fibroblast rate and significantly (p ≤ 0.01) decreased the wound area, total cells, neutrophil, and lymphocyte compared to other groups in rats. The results of FT-IR, UV-Vis, XRD, TEM, and FE-SEM confirm that the aqueous extract of F. vulgaris leaves can be used to yield titanium nanoparticles with a notable amount of remedial effects. 相似文献
88.
89.
90.
Hori T Peng X Aratani N Takagi A Matsumoto T Kawai T Yoon ZS Yoon MC Yang J Kim D Osuka A 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(2):582-595
Starting from 1,3-phenylene linked diporphyrin zinc(II) complex 2ZA, repeated stepwise Ag I-promoted coupling reactions provided linear oligomers from 2nZA up to 128ZA. Of these zigzag shaped porphyrin arrays, the Ag I-promoted intramolecular cyclization reaction of 2 nZA (n=5, 6, 8, 9, 12, and 16) under dilute conditions gave the corresponding cyclic porphyrin wheels C2nZA (n=5, 6, 8, 9, 12, and 16), whereas large arrays 2nZA (n=24, 32, and 48) did not provide cyclic porphyrin products. These large discrete porphyrin arrays and wheels were fully characterized by means of 1H NMR spectroscopy, MALDI-TOF mass spectrometry, UV/Vis absorption spectroscopy, GPC-HPLC analysis, and the scanning tunneling microscopy (STM) technique. The STM images of C12ZA and C18ZA reveal their large circular structures. In the cyclic structures of C2nZA in solution, however, the gradual decrease in fluorescence quantum yields and fluorescence lifetimes are observed, reflecting some conformational heterogeneities. Collectively, the present work provides an important contribution to the construction of fully covalently linked large cyclic arranged porphyrin arrays with ample electronic interactions as a model of light-harvesting antenna. 相似文献