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711.
In the transitional region between the Loess Plateau and deserts, 4 sections located respectively at Yuling, Hengshan, Dingbian
and Huining of China are studied. The high-resolution paleoclimatic records obtained show that environmental events on varying
time scales have happened over East Asia. These events are dated with the time scales established using the recently-developed
approach of Automatic Orbital Tuning. This leads to the establishment of the chronology of the environmental events. 相似文献
712.
An all solid-state electrochromic smart window employing prussian blue and electrodeposited WO3 film with poly (vinyl chloride) (PVC) gel electrolyte that has high conductivity (2 mS/cm) at room temperature has been fabricated
for the first time. The smart window has beell found to be excellent for electrochromism and memory characteristics. 相似文献
713.
InSb nanocrystals embedded in SiO2 thin films were prepared by rf magnetron cosputtering technique. THe observation by transmission electron microscope showed
that InSb nanocrystals dispersed uniformly in SiO2 matrices. InSb nanocrystals with different sizes can be obtained by changing the annealing condition. The average size of
InSb nanocrystals depended on annealing temperature and time, but not on the t1/3 rules. X-ray photoelectron spectroscopy and X-ray diffraction were also applied to the analyses of the composite thin films. 相似文献
714.
In order to ascertain the mechanism of interaction between carbide and metallic catalyst and formation of diamond under high pressure and high temperature, and find a new method to synthesize diamond with special properties, it is necessary to investigate the reaction behavior of different carbides and metallic solvent_catalysts under high pressure and high temperature. A system of Cr-3C-2 powder and Ni 70Mn 25Co 5 alloy in weight ratio of 1∶6 was treated under 6 0 GPa and 1 500℃ for 20, 30 or 60 min respectively. X_ray diffraction of the samples indicated the Cr 3C 2 decomposed partially after high pressure and temperature treatment, and Cr 7C 3, Cr and diamond formed respectively. There was not any trace of graphite in the samples. The result suggested that the separated carbon atoms could form diamond directly without conversion process of graphite into diamond. The observation of SEI, WDX and EDX also showed that diamond crystals were synthesized in the system, which have perfect surfaces and shapes, with the average grain size of about 40 μm. The properties of the crystals are being investigated. 相似文献
715.
The plagioclase amphibolites from Kuokesu area, Kuruktag, Xinjiang occur as enclaves embedded in the granodioritic gneiss. In the light of major elements and REE data, the parent rocks of the plagioclase amphibolites belong to weak_alkaline basalts. Their Nd model ages mainly range from 2 832 to 3 075 Ma. The seven plagioclase amphibolites yield a reasonable good isochron age of (828±86) Ma(2σ) with I Nd =0.510 981±82, ε Nd ( t )=-11.5±1.6. Such a case shows the existence of great proportion of the Archaean mafic crustal basement on the Kuokesu area. The strong tectonic_thermal event at about 820 Ma made the Sm_Nd isotope of the metamorphic rocks homogenization. This event would be associated with the Tarim Movement. 相似文献
716.
717.
单向耦合映象格子的时空混沌同步 总被引:1,自引:1,他引:0
用主动-被动分拆方法实现了单向耦合映象格子系统的时空混沌同步,从理论上给出步范围,并从数值实验上得到验证。该法具有高度保密性,且信号可以完全恢复,特别适用于混沌保密通讯 。 相似文献
718.
Radio ligand binding assays(RLBA) were used to study neuropeptide Y (NPY) receptors in a protozoa Stylonychia mytilus. The experimental results showed that 2-3×10+3/mL Stylonychia cells incubated in Pringsheim solution which contained 3H-NPY could specifically bind 3H-NPY and concomitantly present saturable characteristic. This suggested that Stylonychia possessed some specific binding sites for NPY. Scatchard transformations of binding assay for the NPY receptors at 25℃ are compatible with the specific activity of 42.47 fmol/10+3 cells and the binding equilibrium constant of 0.113 nmol/L. The data of 125I-NPY binding assay to the membrane protein extract of Stylonychia indicated that there was a significant difference between the amount of total bound and nonspecific bound of 125I-NPY. This result indicated that NPY receptors were probably localized mainly on the cell membrane. 相似文献
719.
介绍铁路站场CAD系统中面向对象用户界面的设计与研究,该系统用户界面的设计充分分考虑了铁路站场CAD系统的特点和工程应用,采用面向对象的方法与技术,实现了一个高度图形化和交互式,适用于铁路站场设计工作需要的图用户界面。 相似文献
720.
胡新春 《上海交通大学学报》1998,32(5):64-68
由于传统建模方法缺乏通用性,发展通用建模方法已成为必要.在总结了传统的机电系统数学建模优缺点、引入位移联结、速度联结和加速度联结概念的基础上,提出了适用于非线性机电系统数学建模的通用方法——联结方法.将联结理论从线性系统拓宽于非线性系统,拓展了联结理论.将联结方法与传统的拉格朗日法进行对比,说明了联结方法可避免建模过程中严重偏微分运算的优越性,并从理论上证明了研究结果的可靠性. 相似文献