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排序方式: 共有434条查询结果,搜索用时 15 毫秒
81.
Y. Maeda T. Saito H. Miyasako T. Uesaka S. Ota S. Kawase T. Kikuchi H. Tokieda T. Kawabata K. Yako T. Wakasa S. Sakaguchi R. Chen H. Sakaguchi T. Shima T. Suzuki A. Tamii 《Few-Body Systems》2014,55(8-10):729-732
The effects of three nucleon force (3NF) have been actively studied via the nucleon–deuteron (Nd) scattering states. The differential cross sections and the vector analyzing powers A y of the 2H(p, n) inclusive breakup reaction at 170 MeV were measured for the study of 3NF effects in the intermediate energy region. The polarized proton beam of 170 MeV was injected to the deuterated polyethylene (CD2) target and the energy of scattered neutrons were measured by using TOF method. The data were compared with the Faddeev calculations based on modern nucleon–nucleon (NN) forces with and without the 3NF. Concerning the differential cross sections, we can see large discrepancies between the data and the calculations in the region of scattered neutron energies are low, which is similar to the results of the 2H(p, p) inclusive breakup reaction at 250 MeV. 相似文献
82.
Ken Watanabe Kenji Matsumoto Yutaka Adachi Takeshi Ohgaki Tsubasa Nakagawa Naoki Ohashi Hajime Haneda Isao Sakaguchi 《Solid State Communications》2012,152(20):1917-1920
Isotopic ZnO thin films were deposited on the c-plane of ZnO single crystals by pulsed laser deposition. The isotopic abundance of Zn in the films was determined with a secondary ion mass spectrometry before and after the films was diffusion annealed. The diffusion profiles across the film/substrate interface behaved smooth features. The zinc diffusion coefficient (DZn) was obtained by analyzing the slope of the profile in the annealed sample. The temperature dependence of DZn was determined to be DZn(cm2/s)=8.0×104exp(?417[kJ/mol])/RT, where R and T are gas constant and temperature. The zinc ion diffusion coefficients were of the same order as that in a ZnO single crystal. A comparison of the experimental and theoretical values indicated that the zinc ions diffused in the thin film and the single crystal through a vacancy mechanism. 相似文献
83.
Dr. Kazuhisa Fujimoto Dr. Masaoki Kajino Ikumi Sakaguchi Prof. Dr. Masahiko Inouye 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(32):9834-9840
Diarylethene‐bridged peptides were developed to photoregulate biomolecular interactions. The peptides are made up of diarylethene‐bridged and DNA‐binding regions at their N‐ and C termini, respectively. The two regions could be independently designed and combined as desired. The α‐helicities of the peptides were photoregulated in on/off or off/on manners, and the manner depended on the positions of two ornithine (Orn) residues for cross‐linking reaction at the diarylethene‐bridged region. In the case of the on/off manner, when the diarylethene structure adopted the open form on the peptides, the peptides folded into stable α‐helices. Upon UV irradiation, the diarylethene moiety isomerized to its closed form to destabilize the helical structures. Quartz crystal microbalance (QCM) analysis showed that the open isomer strongly associated with a target DNA, as compared with the closed one. When the closed‐form peptide existing in the DNA complex was irradiated with a fluorescent lamp in the middle of the QCM monitoring, the frequency change (ΔF) was enhanced by the diarylethene photoisomerization. 相似文献
84.
M. Sakaguchi T. OhuraT. Iwata Y. Enomoto-Rogers 《Polymer Degradation and Stability》2012,97(3):257-263
Nano cellulose particles covered with a block copolymer of microcrystalline cellulose and poly(methyl methacrylate) (MCC-block-PMMA) were produced by a solid mechano-chemical polymerization. The polymerization of methyl methacrylate was initiated by chain-end-type microcrystalline cellulose (MCC) radicals (i.e., MCC mechano radicals) on the surface of MCC that were induced by mechanical fracture of β-1,4 glycosidic linkages. The chemically modified cellulose particles with MCC-block-PMMA were fractionated by Soxhlet extraction with chloroform, and resulted in MCC-block-PMMA residue from residue on the filter and MCC-block-PMMA filtrate from filtrate solution. The surface of the MCC particles chemically modified with MCC-block-PMMA in MCC-block-PMMA residue was partially covered with PMMA chains of the MCC-block-PMMA. In contrast, the surfaces of the MCC nanoparticles chemically modified with MCC-block-PMMA in MCC-block-PMMA filtrate were fully covered with PMMA chains of the MCC-block-PMMA. A dispersion of the chemically fully modified MCC nanoparticles in chloroform was optically transparent. The average diameter of the chemically fully modified MCC nanoparticles in chloroform was estimated to be 52 nm. These were confirmed by electron spin resonance, Fourier transform infrared, and 1H nuclear magnetic resonance spectroscopy, by gel permeation chromatography and dynamic light scattering. 相似文献
85.
We consider solutions of initial-boundary value problems for the heat equation on bounded domains in and their spatial critical points as in the previous paper [MS]. In Dirichlet, Neumann, and Robin homogeneous initial-boundary
value problems on bounded domains, it is proved that if the origin is a spatial critical point never moving for sufficiently
many compactly supported initial data being centrosymmetric with respect to the origin, then the domain must be centrosymmetric
with respect to the origin. Furthermore, we consider spatial zero points instead of spatial critical points, and prove some
similar symmetry theorems. Also, it is proved that these symmetry theorems hold for initial-boundary value problems for the
wave equation.
Received October 31, 1997; in final form February 3, 1998 相似文献
86.
A practical catalytic method to convert alkanes into the corresponding oxygen‐containing compounds with O2 under mild conditions using N‐hydroxyphthalimide (NHPI) in the presence or absence of a transition metal was developed. Thus, cyclohexane was successfully converted into adipic acid in good conversion and selectivity by a combined catalytic system consisting of NHPI and Mn(acac)2. Lower alkane such as isobutane was converted into t‐butyl alcohol (83%) under 10 atm of air by NHPI‐Co(OAc)2 system. Alkylbenzene such as toluene was oxidized to benzoic acid in high yield (81%) under normal temperature and pressure of dioxygen in the presence of a catalytic amount of NHPI and Co(OAc)2. ESR measurements showed that phthalimide‐N‐oxyl generated from NHPI under dioxygen atmosphere is a key species in this oxidation and functions as a radical catalyst. 相似文献
87.
88.
Excitation and emission spectra of polyethylene terephthalate and polyethylene 2,6‐naphthalate films
Isuke Ouchi Ryo Miyamura Makoto Sakaguchi Shuuhei Hosaka Masahiko Kitagawa 《先进技术聚合物》1999,10(3):195-198
With excitation by the light of the wavelengths longer than 320 nm, fluorescence spectra of polyethylene terephthalate (PET) films had somewhat different shapes from those excited below 300 nm through the intrinsic absorption of PET molecules. Also, in the measurements taken with a polarizer in front of the receiving monochoromator but none before the sample, the intensity ratio of parallel (to the draw axis of the film) and perpendicular components of the emission spectra was different if excited above 320 nm or below 300 nm. Discussion was made about the first step of pumping photon energy at the wavelengths above 320 nm. Fluorescence spectra of polyethylene 2,6‐naphthalate films showed a mirror image of their absorption spectra, consisting of one broad band having the same polarization as their absorption spectra. Their fluorescence occurred from the lowest excited level, conforming to the Kasha law. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
89.
Radical addition of aldehydes and masked aldehydes like 1,3-dioxolanes to electron-deficient alkenes was achieved by the use of catalytic amounts of BPO and N-hydroxyphthalimide (NHPI) as a polarity-reversal catalyst under mild conditions. Three-component radical coupling of 1,3-dioxolanes, maleates, and alkenes was performed in the presence of BPO and NHPI under similar conditions. 相似文献
90.