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101.
Toshiaki Kaminaka Miki Wadati 《Physics letters. A》2011,375(24):2460-2464
We study higher order solutions of Lieb-Liniger integral equation for a one-dimensional δ-function Bose gas. By use of the power series expansion method, the integral equation is solved and the correction terms which improve the Bogoliubov theory are calculated analytically in the weak coupling regime. Physical quantities such as the ground state energy and the chemical potential are represented by a dimensionless parameter γ=c/ρ, where c is the interaction strength and ρ is the number density of particles while the quasi-momentum distribution function is expressed in terms of a dimensionless parameter λ=c/K, where K is the cut-off momentum. 相似文献
102.
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104.
Toshihiko Ueki Matsumi Doe Yoshiki Morimoto Takamasa Kinoshita Rika Tanaka Kazuo Yoshihara 《Journal of heterocyclic chemistry》2001,38(1):165-172
Hyperolactones A ( 1 ) and C ( 3 ) have been synthesized starting from (S)‐malic acid by a straightforward route. The unique spirolactone skeleton was efficiently constructed by one‐pot reaction as a key step. The absolute stereochemistry of hyperolactones was unambiguously established by this synthesis. 相似文献
105.
106.
Hitoshi Osawa Toshiaki IwazumiHiroko Tokoro Shin-ichi OhkoshiKazuhito Hashimoto Hironobu ShojiEiju Hirai Tetsuya NakamuraSusumu Nanao Yasuhito Isozumi 《Solid State Communications》2003,125(5):237-241
The thermal phase transition of RbMnFe(CN)6 has been observed by Mn and Fe 3p-1s X-ray emission spectroscopy (XES) and 1s X-ray absorption spectroscopy (XAS). The thermal variations of the spin states and the valences of Mn and Fe were determined to be Mn2+(S=5/2)-NC-Fe3+(S=1/2) for the high-temperature (HT) phase and Mn3+(S=2)-NC-Fe2+(S=0) for the low-temperature (LT) phase. These transitions are thus caused by charge transfer between Mn and Fe. The temperature dependences of Mn and Fe 3p-1s XES and 1s XAS were observed as the composition of the spectra of the HT and LT phases. The ratios of the HT component in each spectrum show good agreement with the thermal transition curves observed with magnetic susceptibility measurements. 相似文献
107.
The particle-swarm optimization method has been used to predict the stable high pressure structures up to 300 GPa of hydrogen-rich group 17 chlorine (HnCl, n = 2–7) compounds. In comparison to the group 1 and 2 hydrides, the structural modification associated with increasing pressure and hydrogen concentration is much less dramatic. The polymeric HCl chains already present in the low temperature phase under ambient pressure persist in all the high pressure structures. No transfer of electrons from the chlorine atoms into the interstitial sites is found. This indicates the chemical bonding at high pressure in group 17 elements is fundamentally different from the alkali and alkaline elements. It is found that almost perfectly triangular H3
+ ions can be stabilized in the crystalline structure of H5Cl. 相似文献
108.
Hiroki Hirai Kiichi Nakajima Soichiro Nakatsuka Kazushi Shiren Jingping Ni Shintaro Nomura Toshiaki Ikuta Takuji Hatakeyama 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(46):13785-13789
The development of a one‐step borylation of 1,3‐diaryloxybenzenes, yielding novel boron‐containing polycyclic aromatic compounds, is reported. The resulting boron‐containing compounds possess high singlet‐triplet excitation energies as a result of localized frontier molecular orbitals induced by boron and oxygen. Using these compounds as a host material, we successfully prepared phosphorescent organic light‐emitting diodes exhibiting high efficiency and adequate lifetimes. Moreover, using the present one‐step borylation, we succeeded in the synthesis of an efficient, thermally activated delayed fluorescence emitter and boron‐fused benzo[6]helicene. 相似文献
109.
Development of standards for reliable surface analyses by ISO technical committee 201 on surface chemical analysis
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C. J. Powell R. Shimizu K. Yoshihara S. Ichimura 《Surface and interface analysis : SIA》2015,47(1):127-134
The need for reliable surface analyses together with quality‐management requirements for analytical laboratories led the International Organization for Standardization (ISO) to form its Technical Committee (TC) 201 on Surface Chemical Analysis in 1991. This article describes the organization of TC 201, the strategies that have been found useful for identifying and assessing possible projects for new international standards, and the 57 international standards and other documents prepared to date by TC 201. Standards have now been developed for Auger‐electron spectroscopy, glow‐discharge spectroscopy, various types of scanning probe microscopy, secondary‐ion mass spectrometry, sputter‐depth profiling, total‐reflection X‐ray fluorescence spectroscopy, X‐ray photoelectron spectroscopy, and X‐ray reflectometry. In addition, standards have been developed with definitions of terms used in surface chemical analysis; the handling, preparation of specimens for surface analysis; information and data‐transfer formats; and methods for determining the lateral resolution of beam‐based methods of surface analysis. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
110.
The normal impact of single water drops onto a plane water surface was studied experimentally to reveal the amount of secondary drops produced from the rim of crown-like interfacial structure. Within the experimental ranges tested, the ratio of the total mass of secondary drops to the mass of primary drop was approximately within 0–1 and correlated well as the function of dimensionless parameter K that consisted of the impact Weber number We and the Ohnesorge number Oh (K = We Oh
−0.4). The dependences of the number and the mean diameter of secondary drops on K and dimensionless film thickness were also investigated. 相似文献