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991.
H. Nishiguchi S. Okamoto M. Nishimura H. Yamashita M. Anpo 《Research on Chemical Intermediates》1998,24(8):849-858
The phosphorescence properties of benzophenone included within alkali metal cationexchanged ZSM-5 zeolites were investigated
to clarify the effects of the micro-environment of hostadsorbents on the electronic excited states of guest-molecules included
within the restricted void spaces. Benzophenone included within such cation-exchanged ZSM-5 zeolites was found to exist in
both a protonated and hydrogen-bonded form. It was found that exchanging the cations dramatically affects the ratio of their
contents. Photolysis of these systems revealed that both benzhydrol and benzpinacol were the main products, their yields strongly
depending on the kind of the cations exchanged. Especially, the protonated species was found to play a significant role in
the photoreactions observed with benzophenone included within zeolite cavities. 相似文献
992.
Three-dimensional (3D) reconstruction of a unique particle motion in oscillatory thermocapillary convections in a small-sized half-zone liquid bridge with a radius of O (1 mm) was carried out by applying 3D particle tracking velocimetry (PTV). By placing a small cubic beam splitter above a transparent top rod, simultaneous observation of the particles in the bridge by use of two CCD cameras was realized. Reconstruction of the 3D trajectories and the particle velocity fields in several types of oscillatory flow regimes was conducted successfully for a sufficiently long period without losing particle tracking. 相似文献
993.
We study tunnel magnetoresistance (TMR) through grain boundaries where tunneling electrons interact with localized spins via ferromagnetic exchange interaction. It is shown that spin–flip tunneling due to the exchange interaction gives rise to appreciable effects on TMR, and that TMR increases almost linearly with increasing magnetic field. 相似文献
994.
The actual space-time dependent intensity distribution of a tightly focused (numerical aperture NA = 1.35) Gaussian femtosecond pulse is modeled inside dielectric material. Such focusing is typically used for recording with sub-wavelength resolution inside dielectrics. The multi-pulse structuring inside the bulk and on the surface of sapphire are demonstrated. Formation of nano-cracks and nano-crystals is revealed inside the crystalline sapphire. Ripple formation on the surface is discussed in terms of the efficacy map calculated by theory given in ref. [J.E. Sipe, J.F. Young, J.S. Preston, H.M. van Driel, Laser-induced periodic surface structure. I. Theory, Phys. Rev. B 27 (2) (1983) 1141-1154.]. 相似文献
995.
996.
Asato Kina Yuichi Yasuhara Takahiro Nishimura Hiroshi Iwamura Tamio Hayashi 《化学:亚洲杂志》2006,1(5):707-711
In the 1,4‐addition of phenylboronic acid to α,β‐unsaturated ketones, [Rh(OH)(cod)]2 has a much higher catalytic activity than [Rh(OH)(binap)]2 (cod=1,5‐cyclooctadiene, binap=2,2′‐bis(diphenylphosphanyl)‐1,1′‐binaphthyl). Kinetic studies revealed that the rate‐determining transmetalation step in the catalytic cycle has a large rate constant when [Rh(OH)(cod)]2 is used. 相似文献
997.
Y.?KojimaEmail author A.?Taniguchi M.?Shibata E.?Oyama T.?Nishimura K.?Shizuma Y.?Kawase 《The European Physical Journal A - Hadrons and Nuclei》2004,19(1):77-81
Internal conversion electrons from the decay of 148Ce and 148mPr have been measured with a Si(Li) detector. The radioactive sources were produced by the thermal neutron-induced fission of 235U, followed by an on-line mass separation. K- and L-conversion electrons of the isomeric transition from 148mPr were newly observed at 34.6 and 70.8 keV, respectively. The M3 multipolarity was assigned to this transition from the experimental conversion coefficients, and, consequently, the 76.8 keV isomeric level was found to be a 4- state. Parities of some excited levels in 148Pr were also deduced. 相似文献
998.
Optical Review - A new scheme for reconstruction of a fluorophore target embedded in a semi-infinite medium was proposed and evaluated. In this scheme, we neglected the presence of the fluorophore... 相似文献
999.
Automatized Parameterization of the Density‐functional Tight‐binding Method. II. Two‐center Integrals 下载免费PDF全文
Henryk A. Witek Chien‐Pin Chou Grzegorz Mazur Yoshifumi Nishimura Stephan Irle Bálint Aradi Thomas Frauenheim Keiji Morokuma 《中国化学会会志》2016,63(1):57-68
We present an efficient numerical integration scheme (TWOCENT) to be used in the context of automatized parameterization of the density‐functional tight‐binding (DFTB) method. The accuracy of the integration process is assessed and its range of applicability is discussed. The functionality of the developed code is tested by reproducing the electronic portion of the existing mio parameter sets and by reproducing a series of reference DFT band structures of elemental solids. 相似文献
1000.
Summary In order to test the applicability of the parallel-plate plastometer to the rheological study of filled polymer melts, viscous properties of polyethylene and polystyrene filled with particles and short fibers were measured by this apparatus. Flow curves in the low range of shear rate were obtained by approximating the materials as Ostwald-de-Waele liquids. Up to about 0.5 of the volume fraction of the filler,, there was no problem and the utility of the apparatus was clearly shown. When increased more, the results were not necessarily self-consistent because the flow became unstable. Experiments on samples with high showed that the unstable flow resulted in an apparent yield stress which agreed with that estimated from the Casson's plots.
With 8 figures and 1 table 相似文献
Zusammenfassung Um die Anwendbarkeit des Parallel-Platten-Plastometers für die rheologische Untersuchung von Schmelzen gefüllter Polymerer zu prüfen, wurden mit einem solchen Gerät die viskosen Eigenschaften von Polyäthylen und Polystyrol-Proben gemessen, die mit Teilchen oder kurzen Fasern gefüllt waren. Im Bereich niedriger Schergeschwindigkeiten ließen sich die Fließkurven mit Hilfe der Ostwald-de Waele-Gleichung approximieren. Bis zu einer Füllstoff-Volumenkonzentration von etwa 50% traten keine Komplikationen auf, so daß die Eignung des Geräts für diese Fälle klar erwiesen werden konnte. Wenn jedoch noch weiter gesteigert wurde, waren die Ergebnisse durchweg nicht mehr widerspruchsfrei, da dann der Fließvorgang instabil wurde. Versuche mit hohen Volumenkonzentrationen zeigten, daß die Fließinstabilität eine scheinbare Fließgrenze zur Folge hat, deren Größe mit dem aus einer Casson-Darstellung abgeschätzten Wert in etwa übereinstimmt.
With 8 figures and 1 table 相似文献