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101.
C. Nonaka E. Honda S. Muroya 《The European Physical Journal C - Particles and Fields》2000,17(4):663-673
A full (3+1)-dimensional calculation using Lagrangian hydrodynamics is proposed for relativistic nuclear collisions. This
calculation enables us to evaluate the anisotropic flow of the hadronic matter which appears in non-central and/or asymmetrical
relativistic nuclear collisions. Applying hydrodynamical calculations to the deformed uranium collisions in the AGS energy
region, we discuss the nature of the space-time structure and particle distributions in detail.
Received: 18 July 2000 / Published online: 23 October 2000 相似文献
102.
S. Matsui M. Nonaka T. Nakai T. Inouye 《Journal of magnetic resonance (San Diego, Calif. : 1997)》1999,138(2):220
To relax the high-speed requirement imposed on the gradient system used in solid-state proton imaging, we propose two simple modifications of the magic echo imaging sequence, TREV-16TS. In the first modification, the applied gradient is inverted in the middle of the RF irradiation; the second modification utilizes a sinusoidal gradient synchronized with the RF sequence. It is estimated by experiments that as long as the RF amplitude is at least about 10 times stronger than the resonance offset induced by the gradient, the spatial resolution is not degraded significantly by the line narrowing deterioration due to the gradient applied during the on-resonance RF irradiation. The modifications allow commercially available standard gradients to be used for the magic echo imaging of solids. 相似文献
103.
Naotoshi Nakashima Takeshi Tokunaga Yuko Nonaka Takashi Nakanishi Hiroto Murakami Takamasa Sagara 《Angewandte Chemie (International ed. in English)》1998,37(19):2671-2673
Two reversible one-electron transfers are observed for an electrode device made from C60 and an artificial lipid (see schematic drawing). Cyclic voltammetric studies reveal that the redox couples are unchanged even after 50 cycles, thus indicating that the C60 radical monoanion and the C60 dianion generated in aqueous solution are very stable. 相似文献
104.
Kunio Hiroi Fumiko Kato Takamasa Oguchi Shinya Saito Takanori Sone 《Tetrahedron letters》2008,49(22):3567-3569
α-Allenylcyclopropanedicarboxylates, for which a novel synthetic method has been devised by conjugate addition of a copper hydride (Stryker) reagent to α-cyclopropylpropargylic esters, have been newly found to be smoothly converted to methylenecyclopentene derivatives under mild reaction conditions by further treatment with the copper hydride reagent. The mechanistic pathway is discussed. 相似文献
105.
Atsushi Nakahira Hidezumi Nagata Takamasa Onoki Yuki Yamasaki 《Research on Chemical Intermediates》2008,34(4):347-352
Synthesis of mesoporous MCM-type bulks prepared by hydrothermal hot-pressing (HHP) method using MCM-type mesoporous powder
was attempted. Scanning electron microscopy (SEM), bulk density measurement, N2 adsorption-desorption isotherms and formaldehyde adsorption test have been employed to characterize the bulky products. As
a result, we succeeded in preparing a dense and strong mesoporous bulks with high BET over 1000 m2/g through the hydrothermal hot-pressing method under appropriate conditions. 相似文献
106.
Toshio Fuchigami Zaghloul El-Shahat Kandeel Tsutomu Nonaka Hsien-Ju Tien 《中国化学会会志》1986,33(3):241-244
Various kinds of α-halo ketones readily reacted with disodium (dimercaptomethylene)malononitrile to give the corresponding 34-diamino-2,5-diacylthieno-[2,3-b]thiophenes in good to excellent yields. The reaction was successfully extended to the synthesis of a thienothiophene derivative having two sydnone rings by using the 4-(bromoacetyl)sydnone. 相似文献
107.
We argue that the emission of hadrons with transverse momentum up to about 5 GeV/c in central relativistic heavy ion collisions is dominated by recombination, rather than fragmentation of partons. This mechanism provides a natural explanation for the observed constant baryon-to-meson ratio of about one and the apparent lack of a nuclear suppression of the baryon yield in this momentum range. Fragmentation becomes dominant at higher transverse momentum, but the transition point is delayed by the energy loss of fast partons in dense matter. 相似文献
108.
The effects of ultrasonication on the chemical polymerization of aniline leading to the formation of conducting polyaniline colloids were examined. The formation rate of the colloids was significantly increased under ultrasonication. Furthermore, it was also observed that the morphological structure of the colloids thus prepared was greatly affected by the sonication. The polyaniline colloids were further characterized by a range of techniques including electric resistance meter, gel permeation chromatography, FT-IR and cyclic voltammetry. It is noteworthy that the application of ultrasound to the polymerization resulted in a marked increase in the doping level, which reflected to the high electroconductivity of polyaniline colloids. 相似文献
109.
We have demonstrated the decay of spontaneous emission (SE) from AlN-GaN quantum dots (QDs) into silver surface plasmon (SP) modes in the ultraviolet at approximately 375-380 nm. Using time-resolved photoluminescence (PL), we show that the electron-hole recombination rate in AlN-GaN QDs is enhanced when SE is resonantly coupled to a metal SP mode, corresponding to the dip in the continuous-wave PL spectrum. Exciton recombination by means of silver SP modes is as much as 3-7 times faster than in normal QD SE and depends strongly on emission wavelength and thickness of the silver. 相似文献
110.
Palladium complex catalyzed carbonylation of 2-bromo-3,3,3-trifluoropropene (2-Br-TFP) with ureas afforded 5-trifluoromethyl-5,6-dihydrouracils in moderate to good yields, which were converted into 5-trifluoromethyluracils in nearly quantitative yields. 相似文献