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81.
82.
Yamada K Murugesan R Devasahayam N Cook JA Mitchell JB Subramanian S Krishna MC 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2002,154(2):287-297
The performance of two electron paramagnetic resonance (EPR) spectrometers/imagers, one configured in pulsed mode and the other in continuous wave (CW) mode, at an operating frequency of 300 MHz is compared. Using the same resonator (except for altered Q-factors), identical samples and filling factors in the two techniques have been evaluated for their potentials and limitations for in vivo spectroscopic and imaging applications. The assessment is based on metrics such as sensitivity, spatial and temporal resolution, field of view, image artifacts, viable spin probes, and subjects of study. The spectrometer dead time limits the pulsed technique to samples with long phase memories (>275 ns). Nevertheless, for viable narrow-line spin probes, the pulsed technique offers better sensitivity and temporal resolution. The CW technique, on the other hand, does not restrict the choice at spin probes. In addition, the phase-sensitive narrow-band detection of the CW technique gives artifact-free images even for large objects. Selected examples illustrating the performance of the CW and pulsed techniques are presented to put the capabilities of the two techniques in perspective. 相似文献
83.
Tamotsu Izumida Ken-Ichi Mitani Kichi-Suke Saito 《Central European Journal of Mathematics》2014,12(11):1615-1623
In this paper, we consider a generalized triangle inequality of the following type: $$\left\| {x_1 + \cdots + x_n } \right\|^p \leqslant \frac{{\left\| {x_1 } \right\|^p }} {{\mu _1 }} + \cdots + \frac{{\left\| {x_2 } \right\|^p }} {{\mu _n }}\left( {for all x_1 , \ldots ,x_n \in X} \right),$$ where (X, ‖·‖) is a normed space, (µ1, ..., µ n ) ∈ ? n and p > 0. By using ψ-direct sums of Banach spaces, we present another approach to characterizations of the above inequality which is given by [Dadipour F., Moslehian M.S., Rassias J.M., Takahasi S.-E., Nonlinear Anal., 2012, 75(2), 735–741]. 相似文献
84.
Ken-Ichi Mitani Tomonari Suzuki 《Journal of Mathematical Analysis and Applications》2008,343(1):310-314
In [M. Kato, L. Maligranda, On James and Jordan-von Neumann constants of Lorentz sequence spaces, J. Math. Anal. Appl. 258 (2001) 457-465], the James constant of the 2-dimensional Lorentz sequence space d(2)(ω,q) is computed in the case where 2?q<∞. It is an open problem to compute it in the case where 1?q<2. In this paper, we completely determine the James constant of d(2)(ω,q) in the case where 1?q<2. 相似文献
85.
86.
Mitsuo Ishikawa Ken-Ichi Nakagawa Seiji Katayama Makoto Kumada 《Journal of organometallic chemistry》1981,216(3):C48-C50
Photochemically generated trimethylsilylphenylsilylene reacted with octyl chloride and cyclopropylcarbinyl chloride to give the respective formal carbon-chlorine insertion products. With sec-butyl chloride, trimethylsilylphenylsilylene afforded both the carbon-chlorine insertion product and 1-chloro-1phenyl-2,2,2-trimethyldisilane (IV), while with tert-butyl chloride, IV was obtained as the sole volatile product. 相似文献
87.
Polycrystalline anatase TiO(2)-based thin films with surface roughness were fabricated using a sublimation method. Their surfaces showed hydrophobicity with a water contact angle (CA) higher than 130 degrees when stored in the dark. For the films, the hydrophobic conversion behavior and critical CA depended on surface morphologies. The higher hydrophobic conversion rate and higher critical CA were explained by the smaller r in the Wenzel equation and the smaller f (f = 0.56, 0.30) in the Cassie equation, respectively. Moreover, good reversibility between hydrophobicity (CA = 130 degrees ) and high hydrophilicity (CA = 0 degrees ) was observed by alternating between UV light irradiation and dark storage. The combination of chromium oxide with anatase TiO(2) markedly shortens the period of hydrophobic conversion from 12 to 5 days. 相似文献
88.
Vibrational Raman spectra of CC stretching modes of both cis- and trans-1,2-dichloroethylene (C2H2Cl2) were measured as a function of density in supercritical carbon dioxide (CO2). Measurements were performed with solute mole fraction of 0.01 at an isotherm of T r = T/ T c = 1.02. As the density of CO2 increased, peak frequencies of the CC stretching modes shifted toward the low energy side. By analyzing these density dependences using perturbed hard-sphere theory, we decomposed the shifted amounts into attractive and repulsive components. The amounts of repulsive shifts were almost equivalent, whereas those of the attractive shifts of trans-C2H2Cl 2 were larger than those of cis-C2H2Cl2 at all densities. This means that the nonpolar solute, trans-C2H2Cl2, shows stronger solute-solvent interactions than those of the polar solute cis-C2H2Cl2. The difference of attractive interactions between these isomers is the greatest at a density where local density enhancement of supercritical CO2 reaches the maximum. 相似文献
89.
Takashima H Iwaki K Furukuwa R Takishita K Sawada H 《Journal of colloid and interface science》2008,320(2):436-444
A variety of fluoroalkyl end-capped oligomers were applied to the preparation of fluorinated oligomer/hydroxyapatite (HAp) composites (particle size: 38-356 nm), which exhibit a good dispersibility in water and traditional organic solvents. These fluoroalkyl end-capped oligomer/HAp composites were easily prepared by the reactions of disodium hydrogen phosphate and calcium chloride in the presence of self-assembled molecular aggregates formed by fluoroalkyl end-capped oligomers in aqueous solutions. In these fluorinated HAp composites thus obtained, fluoroalkyl end-capped acrylic acid oligomers and 2-methacryloyloxyethanesulfonic acid oligomer/HAp nanocomposites afforded transparent colorless solutions toward water; however, fluoroalkyl end-capped N,N-dimethylacrylamide oligomer and acryloylmorpholine oligomer were found to afford transparent colorless solutions with trace amounts of white-colored HAp precipitants under similar conditions. HAp could be encapsulated more effectively into fluorinated 2-methacryloyloxyethanesulfonic acid oligomeric aggregate cores to afford colloidal stable fluorinated oligomer/HAp composites, compared to that of fluorinated acrylic acid oligomers. These fluorinated oligomer/HAp composites were applied to the surface modification of glass and PVA to exhibit a good oleophobicity imparted by fluorine. HAp formation was newly observed on the modified polyethylene terephthalate film surface treated with fluorinated 2-methacryloyloxyethanesulfonic acid oligomers and acrylic acid oligomer/HAp composites by soaking these films into the simulated body fluid. 相似文献
90.
Uno H Nakamoto K Kuroki K Fujimoto A Ono N 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(20):5773-5784
Bicyclo[2.2.2]octadiene-connected pyrrolo-porphyrins have been prepared by an inverse-type [3+1] porphyrin synthesis of a bicyclo[2.2.2]octadiene-fused dipyrrole with a tripyrrane dicarbaldehyde. Another [3+1] porphyrin synthesis of pyrrole-connected porphyrins with the same or other tripyrrane dicarbaldehydes gave bicyclo[2.2.2]octadiene-bridged diporphyrins, the central metals and/or peripheral substituents of which were different. Thermal decomposition of the bicyclo[2.2.2]octadiene skeleton to a benzene moiety gave pi-system-fused porphyrin dimers in a highly pure form. 相似文献