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101.
Amemiya F Matsumoto H Fuse K Kashiwagi T Kuroda C Fuchigami T Atobe M 《Organic & biomolecular chemistry》2011,9(11):4256-4265
Product selectivity control based on a liquid-liquid parallel laminar flow has been successfully demonstrated by using a microreactor. Our electrochemical microreactor system enables regioselective cross-coupling reaction of aldehyde with allylic chloride via chemoselective cathodic reduction of substrate by the combined use of suitable flow mode and corresponding cathode material. The formation of liquid-liquid parallel laminar flow in the microreactor was supported by the estimation of benzaldehyde diffusion coefficient and computational fluid dynamics simulation. The diffusion coefficient for benzaldehyde in Bu(4)NClO(4)-HMPA medium was determined to be 1.32 × 10(-7) cm(2) s(-1) by electrochemical measurements, and the flow simulation using this value revealed the formation of clear concentration gradient of benzaldehyde in the microreactor channel over a specific channel length. In addition, the necessity of the liquid-liquid parallel laminar flow was confirmed by flow mode experiments. 相似文献
102.
An isovariant map is an equivariant map preserving the isotropy subgroups. In this paper, we develop an isovariant version
of the Hopf classification theorem; namely, an isovariant homotopy classification result of G-isovariant maps from free G-manifolds to representation spheres under a certain dimensional condition, the so-called Borsuk-Ulam inequality. In order
to prove it, we use equivariant obstruction theory and the multidegree of an isovariant map. 相似文献
103.
Neutralino dark matter is well motivated, but also suffers from two shortcomings: it requires gravity-mediated supersymmetry breaking, which generically violates flavor constraints, and its thermal relic density Omega is typically too large. We propose a simple solution to both problems: neutralinos freeze-out with Omega approximately 10-100, but then decay to approximately 1 GeV gravitinos, which are simultaneously light enough to satisfy flavor constraints and heavy enough to be all of dark matter. This scenario is naturally realized in high-scale gauge-mediation models, ameliorates small scale structure problems, and implies that "cosmologically excluded" models may, in fact, be cosmologically preferred. 相似文献
104.
Theoretical Investigation of Decay Process in a Doubly Excited 2s^2 ^1S0 State of He-Like Ions 下载免费PDF全文
In the framework of multi-configuration Dirac-Fock theory, a detailed calculation is performed for the decay rates and the energies of the doubly excited 2s^2 ^1So state of He-like ions, of which atomic number Z ranges from 6 to 92. The 2s^2 ^1So - ls ^2S1/2 Auger decay is predominant at low Z regime, whereas the 2s^2 ^1So - 1s2p ^1,3P1 two-electron one-photon transitions become quite important in moderate and high Z regimes. For heavy ions with Z ≥ 72, the contribution of 2s^2 ^1So - 1s2s ^3S1 M1 transition is significant. The Breit interaction considerably enhances the 2s^2 ^1So - 1s ^2S1/2 Auger rate at high Z regime. 相似文献
105.
Takahide Nishiyama Fumihiro Endo Hiroko Eguchi Tatsuro Nakagama Nobuko Seino Masaki Shinoda Takuya Shimosaka Toshiyuki Hobo Katsumi Uchiyama 《Analytical sciences》2007,23(4):389-393
An ultra-micro sample injector for gas chromatography (GC) was developed. An ink-jet microchip, originally used for industrial recorder, was modified at the edge near to an orifice, and fixed into the GC. In order to evaluate the characteristics of this injector, a sample injector and a thermal conductive detector (TCD) were connected directly, while water was used as the test sample. The volume of the droplet, the interval time and the back-pressure to the ink-jet microchip were investigated. Within the range of 1 - 5 nL volume injected sample, the TCD response according to the amount of the sample volume (the volume of one droplet from the ink-jet microchip was about 1 nL) was obtained. A good reproducibility of the peak area was obtained to be about 1.0% of the RSD value. In order to compare the injection method of the ink-jet chip with that using a micro-syringe, the method using the ink-jet chip could introduce 1/1000 of the amount of the sample and gave reproducible results. 相似文献
106.
Jonathan L. Feng Arvind Rajaraman Fumihiro Takayama 《General Relativity and Gravitation》2004,36(12):2575-2579
The gravitational interactions of elementary particles are suppressed by the Planck scale M
* ~ 1018 GeV and are typically expected to be far too be weak to be probed by experiments. We show that, contrary to conventional wisdom, such interactions may be studied by particle experiments in the next few years. As an example, we consider conventional supergravity with a stable gravitino as the lightest supersymmetric particle. The next-lightest supersymmetric particle (NLSP) decays to the gravitino through gravitational interactions after about a year. This lifetime can be measured by stopping NLSPs at colliders and observing their decays. Such studies will yield a measurement of Newton's gravitational constant on unprecedentedly small scales, shed light on dark matter, and provide a window on the early universe. 相似文献
107.
Kichinosuke Hirokawa Fumihiro Honda Masaoki Oku 《Journal of Electron Spectroscopy and Related Phenomena》1975,6(5):333-345
Metal and oxide surface reactions formed by heating in the spectrometer at 300–400° at a vacuum of ca. 10?9 Torr (oil diffusion pumps) were studied. As a result of spectral observations before and after heating, the metals studied were classified into five groups. In the first group, oxide films on the metal surface are easily evaporated because of the high vapour pressure of oxide; in the second, the oxide films are easily reduced in the spectrometer; in the third, the oxide film formed on the metal is reduced but the bulk oxide is not easily reduced; in the fourth, very stable oxide films are formed and the bulk oxide is also stable; and finally in the fifth, the oxide film formed on the metal is apparently reduced, yet the bulk oxide is very stable. 相似文献
108.
Fumihiro Sato 《Proceedings Mathematical Sciences》1994,104(1):99-135
The theory of zeta functions associated with prehomogeneous vector spaces (p.v. for short) provides us a unified approach
to functional equations of a large class of zeta functions. However the general theory does not include zeta functions related
to automorphic forms such as the HeckeL-functions and the standardL-functions of automorphic forms on GL(n), even though they can naturally be considered to be associated with p.v.’s. Our aim is to generalize the theory to zeta
functions whose coefficients involve periods of automorphic forms, which include the zeta functions mentioned above.
In this paper, we generalize the theory to p.v.’s with symmetric structure ofK
ε-type and prove the functional equation of zeta functions attached to automorphic forms with generic infinitesimal character.
In another paper, we have studied the case where automorphic forms are given by matrix coefficients of irreducible unitary
representations of compact groups.
Dedicated to the memory of Professor K G Ramanathan 相似文献
109.
Toward total synthesis of miroestrols (miroestrol and deoxymiroestrol), 3-methyl-2-butenyl function (endo-C5 unit) on D ring as a carbon chain for C and E rings was prepared by elongation of the methyl group in α-methyl-α,β-unsaturated ketone unit, and 3,5-dinitrobenzoyl group was introduced as a potential leaving group for the construction of B ring. The former was accomplished through a sequence of epoxide ring-opening, microwave-irradiated siloxy-Cope rearrangement, and isomerization of 3-methyl-3-butenyl function (exo-C5 unit) to endo-C5 unit. 相似文献
110.
Jungkap Park Gus R Rosania Kerby A Shedden Mandee Nguyen Naesung Lyu Kazuhiro Saitou 《Chemistry Central journal》2009,3(1):4-16