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61.
A method for expressing three-dimensional bodies by a Fourier series expansion is proposed. The equivalent ellipsoid which has the same volume, surface area, and an average projected area as those of a test sample is made obtainable simultaneously. Computer application is explained using a cube as the test sample. 相似文献
62.
Two minima in the lithium ionic conductivity vs. composition curve in the lithium nitride-lithium iodide system are observed at Li5NI2 and Li7N2I. It is shown that ionic conductivity minimum at the stoichiometric Li5NI2 is caused by the increase in the lithium ion concentration. 相似文献
63.
A random packing structure constructed by a computer simulation of the slow settling of rigid spheres into a randomly packed bed is investigated, where the bulk-mean volume fraction of the particles is 0.582. Each sphere settled on three others forms a tetrahedron, whose detailed geometrical configuration is successfully examined by a statistical geometrical analysis. 相似文献
64.
Polyethylenetrimesamide (PET), poly(trimesoyl piperazine) (PTP), and poly(m-phenylenetrimesamide) (PMT) were fabricated into thin film composite to evaluate the membrane performance and resistance to oxidative chlorine. The salt rejection of these membrane increased in the following order: PTP<PET<PMT. The degree of performance deterioration of the membrane after the exposure to aq hypochlorous acid was in the following order: PMT>PET>PTP. The reaction behavior of these polyamide membranes with hypochlorous acid could be properly predicted by that of corresponding polyamide powder. Thus, polyethylenetrimesamide has proved to be one of the potential chlorine-resistant reverse osmosis membrane possessing excellent rejection to monosaccharides, amino acids, phenolics, and other solutes having a molar volume larger than 80 cm3/mol. 相似文献
65.
Akira Kaieda Dr. Masashi Takahashi Hiromi Fukuda Dr. Rei Okamoto Dr. Shinji Morimoto Masayuki Gotoh Takahiro Miyazaki Yuri Hori Satoko Unno Dr. Tomohiro Kawamoto Dr. Toshimasa Tanaka Dr. Sachiko Itono Terufumi Takagi Dr. Hiroshi Sugimoto Dr. Kengo Okada Dr. Weston Lane Dr. Bi-Ching Sang Dr. Kumar Saikatendu Dr. Shinichiro Matsunaga Dr. Seiji Miwatashi 《ChemMedChem》2019,14(24):2093-2101
We identified novel potent inhibitors of p38 mitogen-activated protein (MAP) kinase using a structure-based design strategy, beginning with lead compound, 3-(butan-2-yl)-6-(2,4-difluoroanilino)-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one ( 1 ). To enhance the inhibitory activity of 1 against production of tumor necrosis factor-α (TNF-α) in human whole blood (hWB) cell assays, we designed and synthesized hybrid compounds in which the imidazo[4,5-b]pyridin-2-one core was successfully linked with the p-methylbenzamide fragment. Among the compounds evaluated, 3-(3-tert-butyl-2-oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridin-6-yl)-4-methyl-N-(1-methyl-1H-pyrazol-3-yl)benzamide ( 25 ) exhibited potent p38 inhibition, superior suppression of TNF-α production in hWB cells, and also significant in vivo efficacy in a rat model of collagen-induced arthritis (CIA). In this paper, we report the discovery of potent, selective, and orally bioavailable imidazo[4,5-b]pyridin-2-one-based p38 MAP kinase inhibitors. 相似文献
66.
Naohiro Gotoh Yumiko Matsumoto Toshiharu Nagai Hoyo Mizobe Ikuko Otake Kenji Ichioka Ikuma Kuroda Hiroyuki Watanabe Noriko Noguchi Shun Wada 《Food chemistry》2011
The distribution of fatty acid species at the (sn-1, 3) position or the (sn-2) position of triacylglycerol (TAG) in natural fats and oils has already been analysed by many researchers and several interesting results have been reported. However, most of these reports only focused on the distribution of fatty acids at the or positions in TAG, and did not take account of the combination of fatty acids in the TAG, i.e., the TAG positional isomers. In this study, the actual ratios of TAG positional isomer pairs, consisting of palmitic acid and highly unsaturated fatty acid (HUFA) such as DHA or EPA, in fish and marine mammals were investigated using a high-performance liquid chromatography/atmospheric pressure chemical ionisation-mass spectrometry (HPLC/APCI-MS) system equipped with tandem jointed non-endcapped polymeric ODS columns. The results show that for combinations of DHA or EPA with two palmitic acids in the TAG of marine mammals, binding was almost all at the α position. In contrast, binding of DHA or EPA was mainly at the β position in fish. The preferred DHA and EPA positions in TAG were the same in the same marine mammal or fish. The binding position tendency of HUFA in TAG positional isomers consisting of two HUFAs and one palmitic acid was the same as that for combinations of one HUFA and two palmitic acids. These results were interpreted as showing that the preferred fatty acid species of sn-glycerol-3-phosphate acyltransferase and 1-acyl-sn-glycerol-3-phosphate acyltransferase in marine mammals are different to those in fish and other animals, or that diacylglycerol acyltransferase in marine mammals favours 1,2-dipalmitoyl-sn-glycerol formed from 1,2-dipalmitoyl-sn-glycerol-3-phosphatidate if HUFA is the reaction substrate. 相似文献
67.
K. Shimizu R. C. Furneaux G. E. Thompson G. C. Wood A. Gotoh K. Kobayashi 《Oxidation of Metals》1991,35(5-6):427-439
Thermal oxide films grown on electropolished aluminum specimens have been investigated by transmission electron microscopy of stripped oxide films and ultramicrotomed sections. Particular attention has been focused on the nucleation sites -Al
2
O
3
crystals and the relationship of such sites to surface features on the electropolished aluminum surface. It is evident that easy paths for the diffusion of oxygen, or the nucleation sites of -Al
2
O
3
crystals, are not distributed randomly over the electropolished aluminum surface, but form preferentially in the amorphous oxide layer grown over preexisting metal ridges. Thus, the diffusion of molecular oxygen through cracks in the amorphous oxide layer represents the most realistic and acceptable basis for explaining the local growth of the -Al
2
O
3
crystals in thermal oxide films on aluminum, although the cracks have not yet been observed directly.Present address: Alcan International, Ltd., Banbury Laboratories, Banbury, Oxford, OX16 7SP, United Kingdom. 相似文献
68.
Numerical tensile tests of an elastoplastic cylindrical bar at various high strain rates are performed by the use of a dynamic explicit FEM code (DYNA3D, a public domain version). The effects of mass (inertia) of the body, strain rate and strainrate sensitivity exponent (m-value) on the deformation pattern and the load curve are investigated. As for the material, strain-dependent nth power work hardening property is given by
where
is strain rate. The range of the prescribed average strain rate is 50–1000/s where the tensile tests with constant average strain rate and with constant tensile velocity are performed. Materials with higher density exert a greater influence on deformation mode at a high strain rate. Even if the tensile speed is less than that of plastic wave propagation, the deformation becomes non-uniform remarkably due to mass effect. It is unexpected that double necking occurs at certain computational conditions. The strain at maximum load point predicted by the numerical simulation does not coincide with the analytically predicted one. Maximum rate of decrease in cross sectional area within the straight portion of the bar is compared with Hart's instability criterion based on the imperfection in the cross section. In high-rate tension over
, deformation behavior is chaotic in the sense that it varies very sensitively with a trivial change in material properties and/or in the prescribed strain rate. 相似文献
69.
Two Au fixed points filled using metal of different nominal purities in carbon crucibles have been developed at the National Research Council Canada (NRC). The primary motivation behind this project was to provide the means for direct thermocouple calibrations at the Au freezing point (\(1064.18~^\circ \hbox {C}\)). Using a Au fixed point filled with the metal of maximum available purity [99.9997 % pure according to glow discharge mass spectroscopy (GDMS)], multiple freezing plateaus were measured in a commercial high-temperature furnace. Four Pt/Pd thermocouples constructed and calibrated in-house were used to measure the freezing plateaus. From the calibration at Sn, Zn, Al and Ag fixed points, the linear deviation function from the NIST-IMGC reference function (IEC 62460:2008 Standard) was determined and extrapolated to the freezing temperature of Au. For all the Pt/Pd thermocouples used in this study, the measured EMF values agree with the extrapolated values within expanded uncertainty, thus substantiating the use of 99.9997 % pure Au fixed point cell for thermocouple calibrations at NRC. Using the Au fixed point filled with metal of lower purity (99.99 % pure according to GDMS), the effect of impurities on the Au freezing temperature measured with Pt/Pd thermocouple was further investigated. 相似文献
70.
The influence of atmospheric humidity on dry separation of particles was experimentally investigated, making use of the difference in particle motion on an inclined wall, due to different geometrical characteristics. Using a tilted rotating cylinder with blades, glass beads with size and shape distributions were separated according to their geometrical characteristics under various levels of humidity. Fractional recovery of particles is discussed in relation to shape and size of particle and humidity. An angle of repose of the particles was also measured in order to determine the influence of adhesion force, which is closely related to humidity.Glass beads were separated predominantly based on their shape characteristics. Fractional recovery of particles changes strongly around a relative humidity of 60-70%, at which point the angle of repose also changes markedly. The influence of interaction between particles, which becomes significant for smaller particles, was found to reduce the fractional recovery and diminish the influence of humidity. 相似文献