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61.
62.
Chen Rong Kazuya Mitsuji Xue Songtao Yoshihiro Sugimura Masanori Izumi 《Acta Mechanica Solida Sinica》1999,12(2):144-154
The purpose of this paper is to study the dynamic behavior of soft ground including a porous layer by considering the porosity
change. In order to take the porosity change into account, the concept of the volume fraction, which has been proposed in
continuum mechanics, is introduced. The constitutive equations presented by Bowen are applied to the analysis of the porous
media. According to Bowen's theory, the porosity is considered as a variable called the volume fraction and has its own constitutive
equation. The constitutive equation of the volume fraction has thermoelastic equation coefficients and is determined by the
strains of the solid and the fluid. This means that the compressibilities of the solid and the fluid are considered. When
the special condition is assumed, Bowen's theory can contain Biots's theory, which has been applied in earthquake engineering.
The wave propagation in the ground including a porous layer, modeled by Bowen's theory, is studied and compared with that
of Biot's theory. One-dimensional attenuation and surface amplitude are calculated. The effect of the volume fraction is discussed
with respect to the compressibilities of the solid and the fluid. 相似文献
63.
Akira Kasahara Taeko Izumi Satoshi Murakami Kazuhiro Miyamoto Toshimi Hino 《Journal of heterocyclic chemistry》1989,26(5):1405-1413
The palladium-catalyzed cross-coupling reaction of 2-bromonitrobenzenes or 2-bromoacetanilides with ethylene has been used to produce a variety of substituted indoles. The mild reaction conditions and selectivity inherent in the coupling reaction have been utilized to produce regiochemically pure 4-, 5-, 6-, and 7-substituted indoles. 相似文献
64.
M. Kambara K. Miyake K. Murata T. Izumi Y. Shiohara T. Umeda 《Physica C: Superconductivity and its Applications》2000,330(3-4):191-202
Crystal growth of the melt-textured bulk Nd1+xBa2−xCu3O6+d (Nd123) superconducting oxides was investigated by employing isothermal undercooling solidification with hot-seeding in air. From the relationship between growth length and holding time, the Nd123 crystal was found to have almost stopped growing after a certain growth period, while the growth length increased proportionally to the holding time at an early stage of the crystal growth. As a result of quantitative analysis for the Nd123 crystal of which solidification was terminated, the distribution of the Nd/Ba substitution was observed to decrease in the Nd123 single crystal matrix from the seed crystal to the edge of the Nd123 crystals. Also, the substitution content at the edge of the Nd123 crystal, which corresponds to that at the final stage of the crystal growth, was found to be in good agreement with the minimum substitution of the Nd123 solid solution phase in the equilibrium phase diagram at this process temperature. These compositional changes could be explained using the equilibrium phase diagram as associated with the solid solution formation, which is responsible for the non-steady state solidification of the Nd123 crystals even for the isothermal undercooling processing. 相似文献
65.
Tomohiro Narukawa Takayoshi Kuroiwa Izumi Narushima Koichi Chiba 《Analytical sciences》2008,24(3):355-360
The sensitivity of graphite furnace atomic absorption spectrometry (GFAAS) to arsenobetaine (AB) was 1.3-times higher than to inorganic As. In order to understand the mechanism underlying this observation, the atomization processes for both chemical species were investigated in terms of the enthalpy change (DeltaH) during the atomization process in GFAAS. The enthalpy change of AB was slightly lower than that of inorganic As, which suggested that AB was atomized more efficiently than was inorganic As. Moreover, it was observed that some co-existing organic materials enhanced the analytical sensitivity of inorganic As. The sensitivity difference between inorganic As and AB depended upon the mechanisms of their atomization processes. 相似文献
66.
Minoru Ishikura Machiko Kamada Izumi Oda Tsukasa Ohta Masanao Terashima 《Journal of heterocyclic chemistry》1987,24(2):377-386
The reaction of various lithium tributylheteroarylborates with allylic bromides in the presence of copper(I) cyanide furnished the regioselective allylation at the heteroaryl ring. 相似文献
67.
Yuko Okamoto Toshimasa Tanaka Hironori Kokubo 《Journal of computer-aided molecular design》2010,24(8):699-712
We performed replica-exchange molecular dynamics (REMD) simulations of six ligands to examine the dependency of their free
energy landscapes on charge parameters and solvent models. Six different charge parameter sets for each ligand were first
generated by RESP and AM1-BCC methods using three different conformations independently. RESP charges showed some conformational
dependency. On the other hand, AM1-BCC charges did not show conformational dependency and well reproduced the overall trend
of RESP charges. The free energy landscapes obtained from the REMD simulations of ligands in vacuum, Generalized-Born (GB),
and TIP3P solutions were then analyzed. We found that even small charge differences can produce qualitatively different landscapes
in vacuum condition, but the differences tend to be much smaller under GB and TIP3P conditions. The simulations in the GB
model well reproduced the landscapes in the TIP3P model using only a fraction of the computational cost. The protein-bound
ligand conformations were rarely the global minimum states, but similar conformations were found to exist in aqueous solution
without proteins in regions close to the global minimum, local minimum or intermediate states. 相似文献
68.
Non-extractable photoinitiators based on thiol-functionalized benzophenones and thioxanthones 总被引:1,自引:0,他引:1
Hironori Matsushima Qin Li Masamitsu Shirai Charles E. Hoyle 《European Polymer Journal》2010,46(6):1278-1287
Non-extractable photoinitiators could be advantageous for use in biological, electronic, and food packaging applications. Therefore, thioxanthone and benzophenone derivatives were synthesized from 1,6-hexane dithiol and chlorinated benzophenone or thioxanthone. The efficiency of thiol-functionalized photoinitiators in combination with amine co-initiators was compared to benzophenone and isopropylthioxanthone with amine co-initiators, and the cleavage of photoinitiator 2,2-dimethoxy-1,2-diphenylethan-1-one in acrylic resins. The reaction kinetics were analyzed using photo-differential scanning calorimetry and real-time FTIR. Coating physical properties were evaluated by pendulum and pencil hardness, steel-wool scratch and mandrel bend tests. The non-extractable photoinitiators had higher absorbance than their benzophenone or isopropylthioxanthone counterparts due to the sulfide substitution on the phenyl ring, and the free thiol groups reacted with the acrylate by either an amine catalyzed Michael addition or a free-radical chain process. The combination of thiol-functionalized photoinitiators with secondary amines provides an efficient photoinitiator system that is locked into the photopolymerized network and cannot be extracted with typical solvents. 相似文献
69.
A LiMnPO4/C composite cathode was prepared by a combination of spray pyrolysis and wet ball milling. The cathode showed stable performance at various cutoff voltages up to 4.9 V. The cutoff voltage increase up to 4.9 V allowed the achievement of a high discharge capacity in galvanostatic charge–discharge tests. The discharge capacities of 153 mAh g?1 at 0.05 C and 149 mAh g?1 at 0.1 C were achieved at room temperature; the trickle-mode discharge capacities at room temperature were 132, 120 and 91 mAh g?1 at 0.1, 1 and 5 C discharge rates, respectively. The cell exhibited a good rate capability in the galvanostatic cycling up to 5 C discharge rates at both ambient temperature and 50 °C. 相似文献
70.
Tomohiro Narukawa Takayoshi Kuroiwa Izumi Narushima Yasujiro Jimbo Toshihiro Suzuki Koichi Chiba 《Analytical and bioanalytical chemistry》2010,397(2):493-499
Arsenate [As(V)] solution reference material, National Metrology Institute of Japan (NMIJ) certified reference material (CRM)
7912-a, for speciation of arsenic species was developed and certified by NMIJ, the National Institute of Advanced Industrial
Science and Technology. High-purity As2O3 reagent powder was dissolved in 0.8 M HNO3 solution and As(III) was oxidized to As(V) with HNO3 to prepare 100 mg kg-1 of As(V) candidate CRM solution. The solution was bottled in 400 bottles (50 mL each). The concentration of As(V) was determined
by four independent analytical techniques—inductively coupled plasma mass spectrometry, inductively coupled plasma optical
emission spectrometry, graphite furnace atomic absorption spectrometry, and liquid chromatography inductively coupled plasma
mass spectrometry—according to As(V) calibration solutions, which were prepared from the arsenic standard of the Japan Calibration
Service system and whose species was guaranteed to be As(V) by NMIJ. The uncertainties of all the measurements and preparation
procedures were evaluated. The certified value of As(V) in the CRM is (99.53 ± 1.67) mg kg-1 (k = 2). 相似文献