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1.
Yang T. L. Kao C. L. Kuo C. E. Yeh H. C. Li W. J. Li H. T. Chen C. Y. 《Chemistry of Natural Compounds》2022,58(5):825-827
Chemistry of Natural Compounds - A novel bibenzyl derivative, hydrangchinenin (1), was isolated from the stems of Hydrangea chinensis Maxim. (Hydrangeaceae). Its structure was determined on the... 相似文献
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We start with a stochastic flow of diffeomorphisms of the space. Particles enter the space at random times and places. Each particle is carried by the flow for some random amount of time. We examine the point process formed by the particles at a fixed time, on the evolution of that point process as time varies, and on the equilibrium law of the point process. 相似文献
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Heavy ion irradiation in the electronic stopping power region induces macroscopic dimensional change in metallic glasses and introduces magnetic anisotropy in some magnetic materials. The present work is on the irradiation study of ferromagnetic metallic glasses, where both dimensional change and modification of magnetic anisotropy are expected. Magnetic anisotropy was measured using Mössbauer spectroscopy of virgin and irradiated Fe40Ni40B20 and Fe40Ni38Mo4B18 metallic glass ribbons. 90 MeV 127I beam was used for the irradiations. Irradiation doses were 5×1013 and 7.5×1013 ions/cm2. The relative intensity ratios D 23 of the second and third lines of the Mössbauer spectra were measured to determine the magnetic anisotropy. The virgin samples of both the materials display in-plane magnetic anisotropy, i.e., the spins are oriented parallel to the ribbon plane. Irradiation is found to cause reduction in magnetic anisotropy. Near-complete randomization of magnetic moments is observed at high irradiation doses. Correlation is found between the residual stresses introduced by ion irradiation and the change in magnetic anisotropy. 相似文献
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This work examines the curing kinetics, thermal properties, and decomposition kinetics of diglycidyl ether of bisphenol A (DGEBA) epoxies with three different curing agents, 2-(6-oxido-6H-dibenz(c,e)(1,2)oxaphosphorin-6-yl)-1,4-naphthalenediol (ODOPN), bisphenol A (BPA), and bisphenol S (BPS). The differential scanning calorimetry curing study reveals that the curing kinetics of the DGEBA/ODOPN epoxy is first order, independent of the scan rate. The ODOPN-containing epoxy, unlike the conventional BPA one, includes a phosphorus-containing bulky pendant aromatic group and results in an increase in the glass-transition temperature of 83 K, the char yield increases by a factor of 3, and the limiting oxygen index values increase from 23 to 27. For the BPS system, the glass-transition temperature increased slightly, and both the char yield and the limiting oxygen index value increased insignificantly when the test was conducted in air. Finally, the thermogravimetric analysis decomposition study in N2 from Ozawa's analysis demonstrates that the DGEBA/BPS epoxy has the highest activation energy, followed by the regular DGEBA/BPA system, and lastly the DGEBA/ODOPN has the lowest activation energy. The low activation energy for the ODOPN system is attributed to the initial decomposition of the phosphorus compound in the formation of an insulating layer. 相似文献
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From the wood of Taiwania cryptomerioides Hayata, two new sesquiterpenes, cadinan-3β, 9β-diol and cadinan-3β, 9α-diol were isolated as minor components. Their structures were elucidated as (I) and (II), respectively. 相似文献
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