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101.
Yoshiko Ikebe Micha A. Perles Akihisa Tamura Shinnichi Tokunaga 《Discrete and Computational Geometry》1994,11(1):51-63
In this paper we show that any rooted tree ofn vertices can be straight-line embedded into any setS ofn points in the plane in general position so that the image of the root is arbitrarily specified. 相似文献
102.
A computer program, HALTAFALL, is described which calculates the equilibrium concentrations of the species in mixtures of any number of components, which can form any number of complexes and solid phases, provided concentrations (or partial pressures) can be used in the equilibrium calculations. Of course, the equilibrium constants must be known and enough data be given about the gross composition. Some applications are indicated. The flexible input rules make it applicable to a variety of problems. From the input information, the program itself devises an efficient plan for solving the simultaneous equations. The program also provides an efficient means of finding out which of many possible solid phases can actually appear in a certain equilibrium mixture. 相似文献
103.
104.
We have measured antinormally ordered Hanbury Brown-Twiss correlations for coherent states of the electromagnetic field by using a stimulated parametric down-conversion process. Photons were detected by stimulated emission, rather than by absorption, so that the detection responded not only to actual photons but also to zero-point fluctuations via spontaneous emission. The observed correlations were distinct from normally ordered ones as they showed excess positive correlations, i.e., photon bunching effects, which arose from the thermal nature of zero-point fluctuations. 相似文献
105.
Maeda Y Rahman GM Wakahara T Kako M Okamura M Sato S Akasaka T Kobayashi K Nagase S 《The Journal of organic chemistry》2003,68(17):6791-6794
A photochemical reaction of C(60) with disilane in a 2:3 ratio affords the isomer mixture of the tetrakis-adduct of C(60)((t)BuPh(2)Si)(4) as the major product. The use of a three-stage HPLC separation system isolated three of their isomers. Their structural assignments were based on FAB mass, UV-vis, NMR, and cyclic voltammetry (CV) measurements. The CV analysis showed that the terakis-adduct has lower oxidation and higher reduction potentials than the bis-adduct C(60)((t)BuPh(2)Si)(2) and the parent C(60). 相似文献
106.
Nature‐Inspired Environmental “Phosphorylation” Boosts Photocatalytic H2 Production over Carbon Nitride Nanosheets under Visible‐Light Irradiation 下载免费PDF全文
Guigao Liu Dr. Tao Wang Dr. Huabin Zhang Xianguang Meng Dr. Dong Hao Dr. Kun Chang Dr. Peng Li Dr. Tetsuya Kako Prof. Jinhua Ye 《Angewandte Chemie (International ed. in English)》2015,54(46):13561-13565
Inspired by the crucial roles of phosphates in natural photosynthesis, we explored an environmental “phosphorylation” strategy for boosting photocatalytic H2 production over g‐C3N4 nanosheets under visible light. As expected, a substantial improvement was observed in the rate of H2 evolution to 947 μmol h?1, and the apparent quantum yield was as high as 26.1 % at 420 nm. The synergy of enhanced proton reduction and improved hole oxidation is proposed to account for the markedly increased activity. Our findings may provide a promising and facile approach to highly efficient photocatalysis for solar‐energy conversion. 相似文献
107.
Mesoporous zinc germanium oxynitride was synthesized by a template-free method at high temperature. Through optimizing redox potentials as well as improving crystallinity, this material showed enhanced activity in CO(2) photoreduction. 相似文献
108.
Asao N Hatakeyama N Menggenbateer Minato T Ito E Hara M Kim Y Yamamoto Y Chen M Zhang W Inoue A 《Chemical communications (Cambridge, England)》2012,48(38):4540-4542
Aerobic oxidation of alcohols in the liquid phase proceeded smoothly in the presence of nanoporous gold catalyst. The catalyst is reusable multiple times without leaching and loss of the catalytic activity. The reaction was applied successfully to a flow system. Adsorptions of O(2) and 1-phenylethanol into the AuNPore were confirmed by TDS analysis. 相似文献
109.
We show two discrete zero point theorems that are derived from Sperner’s lemma and a Sperner-like theorem (van der Laan and Talman [Math. Oper. Res. (1982)] [5]; Freund [Math. Oper. Res. (1986)]) [3]. Applications to economic and game models are also presented. 相似文献
110.
Yoshihiko Yokoyama Takehiko Ishikawa Junpei T. Okada Yasuhiro Watanabe Susumu Nanao Akihisa Inoue 《Journal of Non》2009,355(4-5):317-322
We examined the volume and viscosity of Zr–Cu–Al glass-forming liquid alloys to clarify the origin of a frozen free volume in glassy alloys. Since an excess free volume imparts toughness and ductility to glassy alloys, we attempted to increase this volume in glass structures so that they could be used as engineering materials. The maximum frozen excess free volume was observed in the ternary eutectic composition of the Zr–Cu–Al alloy system; however, its origin remains unclear. We attempted to reveal the mechanism of the formation of the frozen excess free volume in Zr–Cu–Al glassy alloys. 相似文献