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101.
Ri-Xing Wang Quan-Hui Liu An-Lian Pan Yan-Guo Wang 《Journal of magnetism and magnetic materials》2010,322(15):2264-2267
A theoretical study is presented on the current-driven ferromagnetic resonance in the magnetic trilayers. On the basis of the Landau-Lifshitz-Gilbert-Slonczewski equation, we derive the output dc voltage for arbitrary anisotropy in the free and pinned layers by the linearization method. As an example, the resonance spectra of the tilted-polarizer and perpendicular-analyzer trilayer show that the equilibrium position, the resonant linewidth and the resonant location can be tuned by changing the magnitude and the direction of spin torque. The effective damping can be minimized through adjusting the current and the pinned-layer magnetization direction. 相似文献
102.
A method has been developed for the preparation of modified silica plates for high performance thin-layer chromatography (HPTLC). Some typical organosilanes were thus allowed to react in situ with the silica of Merck HPTLC-plates. This method was found to be highly reproducible, simple and cheap. Non-polar plates were prepared and compared with commercial plates from Merck, Whatman and Macherey-Nagel. Modification with cyanodecyltrichlorosilane resulted in plates that showed good coverage, efficiency and low residual silica activity. Silica modified with a multifunctional silane has different properties in different organic solvents. It will appear to be non-polar in a polar solvent and vice versa. New advantageous separation systems are thus made feasible by the presence of cyano groups on the plate. The utility of modified thin-layer plates is demonstrated by the separation of some homologues of p-hydroxybenzoic acid esters and of some polycyclic aromatic hydrocarbons. 相似文献
103.
104.
王剑 《温州大学学报(自然科学版)》2004,25(6):101-104
杨贤江在并不长的理论研究生涯中,形成了“全人生指导”、马克思主义教育理论等对中国教育理论发展有深远理论贡献的成就,这诸多成就的取得是与杨贤江在教育实践和理论研究过程中坚持的教育创新思想是分不开的. 相似文献
105.
Two-pyroxene granulite and clinopyroxene granulite xenoliths have been recently discovered in the Late Paleogene toNeogene volcanic rocks (with ages in the range of 4.27~44.60 Ma) that outcropped in Hoh Xil, central Tibetan plateau. Based on theelectron microprobe analysis data, the xenoliths provide constraints for the formation equilibrium temperatures of the two-pyroxene gran-ulite being about 783 to 818℃ as determined by two-pyroxene thermometry and the forming pressure of the clinopyroxene granulite beingabout 0.845 to 0.858 GPa that is equivalent to 27.9~28.3 km depth respectively. It indicates that these granulite xenoliths represent thesamples from the middle part of the thickened Tibetan crust. This discovery is important and significant to making further discussion onthe component and thermal regime of the deep crust of the Tibetan plateau. 相似文献
106.
通过对02215综采工作面过20102回撤通道的支护设计、矿压情况、劳动组织和回采工艺的阐述,提出了过空巷的工艺。 相似文献
107.
108.
介绍乌龙江特大桥的方案设计.根据有关要求和桥址水文地质自然条件,主跨采用下承式预应力系杆钢管混凝土拱.由于建筑高度低,因而可压低引桥及路堤高度,缩短桥长,节约投资.引桥上部结构采用部分预应力混凝土设计,下部结构采用桩柱直接支承大梁,结构合理经济 相似文献
109.
以单台2 MW直驱永磁同步风力发电机(direct-driven permanent magnet synchronous wind power generator,D-PMSG)为研究对象,分别建立了风机、永磁同步电机、变流器等环节的数学模型。参考我国发布的风电场低电压穿越(low-voltage ride through,LVRT)标准,基于Matlab/Simulink建立整个系统仿真模型。对三种电压跌落故障情况下的风力发电机组动态响应特性进行仿真,对比分析不同故障下各个变量不同的变化情况;并对其相应的控制策略进行了探讨,为更进一步研究低电压穿越标准下的控制策略提供了依据。 相似文献
110.
Palynological studies on the Vitab?ck Clay help resolve the position of the Jurassic-Cretaceous boundary in southern Sweden. Well-preserved assemblages of terrestrial pollen and spores, together with abundant algae (Botryococcus), and for the first time, dinoflagellates have been identified in the Vitab?ck Clay. A Berriasian age is corroborated for the Vitab?ck Clay based on the palynological data; the Jurassic-Cretaceous boundary being placed around the contact of this unit with the underlying “Nytorp Sand”. The terrestrial vegetation was dominated by coniferous forest with an understorey of ferns in a warm, temperate climate. The palynoflora shows compositional similarities to the Northern Chinese Floral Province and especially the Jehol Group. The majority of the Vitab?ck Clay represents a moderate-to low-energy paralic succession. However, the basal part of the unit incorporates anomalously coarse material of mixed terrestrial and marine origin. This sedimentary package is herein interpreted to represent tsunami deposits and is similar to coeval tsunami-related deposits in France. 相似文献