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41.
The original method is developed for producing the new inorganic sorption material of akaganeite bgr-FeO(OH). The material in question is characterized relative to arsenic contained in aqua. The possibility is established for removing arsenate ions from water by contemporary physicochemical methods.  相似文献   
42.
The formation of a crosshatched morphology during crystallization of an isotactic polypropylene with low crystallinity is studied in detail. Here, a lamella seems to grow through another nearly perpendicular lamella that was crystallized before. The crystallization was observed with in situ scanning force microscopy with a temporal resolution of 3 min per image. After crystallization the volume structure was imaged by nanotomography. A detailed scheme for the nucleation of branches is proposed.  相似文献   
43.
针对铁路提速后出现的上承式简支钢板梁桥跨中横向振幅过大的问题,以羊楼司桥(L=32m单跨上承式简支钢板梁桥)为例进行实桥检测和数值模拟,建立车辆、线路、桥梁三者的联合模型,考虑轮轨接触力,应用MSC/DYTRAN大型结构分析程序进行车线桥动力相互作用的仿真分析。研究揭示我国用量最多的C62型货车以70∽80km/h的速度空载通过时,该跨度的钢板梁桥发生横向谐振的机理。此外,用该方法对32m跨长的组合梁结构进行桥梁动力特性及列车走行性分析,表明该结构满足提速货车和高速电动旅客列车走行的要求。研究结果对我国高速铁路桥梁建设和既有桥梁的改造具有积极意义。  相似文献   
44.
Epitaxial lamellar gallium selenide (GaSe) semiconductors have been grown on trench-patterned silicon (Si) substrates by molecular beam epitaxy. An intriguing star-like patterned morphology was identified by atomic force microscopy on these epilayers. This non-trivial feature can be correlated with the accumulation of stacking faults of two concurrent epitaxial domains around self-oriented triangular pits developed earlier on the Si(111) surface by the chemical etching. Crystallographic considerations show how the stars can be formed.  相似文献   
45.
刘守基 《山西电力》2003,(5):24-25,46
简要论述了轧制力测量的基本原理,并从实际经验出发深入探讨了测压头的维护与管理要点。  相似文献   
46.
You-Yi Xia 《Materials Letters》2007,61(21):4321-4324
This paper describes a solution-phase approach to the synthesis of selenium nanoparticles by reducing selenious acid solution with ascorbic acid in the presence of silk fibroin. The monodispersed spherical selenium colloid particles obtained were very stable in silk fibroin solution and characterized by Atomic force microscopy and X-ray techniques. The influences of temperature and ultrasonication on the morphology of selenium nanoparticles were also discussed. The experiments showed that the selenium nanoparticles with various morphologies could be obtained under different temperatures and the appropriate ultrasonication time was 60 min. This result indicated that the silk fibroin molecules intimately associated with the surface of the selenium particles and controlled the growth particles.  相似文献   
47.
本文介绍了一种作业效率高、省时省力新型的转炉炉底车,其特点是转盘转动灵活,炉底车上项盘径向任意方向均能平稳倾斜一定角度,以保证炉底圆周所受项力均匀可靠,满足炉底安装要求。  相似文献   
48.
Many everyday activities depend on the capacity to organize and smoothly execute motor sequences. The authors tested the hypothesis that a sequencing deficit is associated with schizophrenia. They used a new method to distinguish between lower and higher order mechanisms for the impairment. The 1st task involved triggered sequences in which sensory information from 1 movement was the cue for initiation of the following movement. Results showed that the motor sequences were performed as fluently in patients as in controls. The 2nd and 3rd tasks involved sequences in which the entire movement sequence could be preplanned. Patients executed the sequences less fluently than controls but only under the condition where action sequences were required. Furthermore, the patients' fluency deficit increased with sequence complexity. The high discrimination power of Task 3 gave the authors a means to control for a potential psychometric confound involving differential discriminating power and to argue in favor of a specific higher order motor fluency deficit in patients with schizophrenia. It is suggested that basic lower order mechanisms that integrate sensory information with outgoing motor commands are preserved in schizophrenia, whereas higher order integrative mechanisms that are required for the smooth coordination of motor sequences are impaired. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
49.
In the last decade we have witnessed a rapid growth of Humanoid Robotics, which has already constituted an autonomous research field. Humanoid robots (or simply humanoids) are expected in all situations of humans’ everyday life, “living” and cooperating with us. They will work in services, in homes, and hospitals, and they are even expected to get involved in sports. Hence, they will have to be capable of doing diverse kinds of tasks. This forces the researchers to develop an appropriate mathematical model to support simulation, design, and control of these systems. Another important fact is that today’s, and especially tomorrow’s, humanoid robots will be more and more humanlike in their shape and behavior. A dynamic model developed for an advanced humanoid robot may become a very useful tool for the dynamic analysis of human motion in different tasks (walking, running and jumping, manipulation, various sports, etc.). So, we derive a general model and talk about a human-and-humanoid simulation system. The basic idea is to start from a human/humanoid considered as a free spatial system (“flier”). Particular problems (walking, jumping, etc.) are then considered as different contact tasks – interaction between the flier and various objects (being either single bodies or separate dynamic systems).  相似文献   
50.
本文提出二种算法分别标号和计数线性八元树表示的三维客体群的连通分量.这些操作典型地需要检查线性八元树中诸八分体在三个主方向上的面邻接对.根据这些邻接对,可以建造在计算机中用关联矩阵表示的邻接图.连通分量标号和计数是在关联矩阵上分别执行相应的操作而完成的.连通分量标号的执行时间是O(n+m·logm),而连通分量计数需要O(n)时间,其中m和n分别是线性八元树中八分体和邻接对的数目.  相似文献   
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