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31.
Yufeng Su Hong Wang Guifu Ding Feng Cui Weiping Zhang Wenyuan Chen 《IEEE transactions on magnetics》2005,41(12):4380-4383
We describe the preparation of CoNiMnP-based permanent-magnet material using several sulfate and chloride solutions. We studied eight samples, and all the samples show vertical magnetic anisotropy. Sample8, which was electroplated from a low-concentration chloride solution and under external magnetic field, demonstrates the best magnetic properties with coercivity 2632 Oe, remanence 0.20 T, and maximum magnetic energy 10.185 kJ/m/sup 3/. An array structure can avoid the stress between the electroplated layer and the seed layer. The electroplated Co/sub 0.8/Ni/sub 0.1174/Mn/sub 0.0062/P/sub 0.0762/ permanent magnet has potential for bidirectional actuators in micro-electromechanical systems. 相似文献
32.
Su Guanghui K. Morita K. Fukuda Mark Pidduck Jia Dounan Jaakko Miettinen 《Nuclear Engineering and Design》2003,220(1):17-35
Artificial neural networks (ANNs) for predicting critical heat flux (CHF) under low pressure and oscillation conditions have been trained successfully for either natural circulation or forced circulation (FC) in the present study. The input parameters of the ANN are pressure, mean mass flow rate, relative amplitude, inlet subcooling, oscillation period and the ratio of the heated length to the diameter of the tube, L/D. The output is a nondimensionalized factor F, which expresses the relative CHF under oscillation conditions. Based on the trained ANN, the influences of principal parameters on F for FC were analyzed. The parametric trends of the CHF under oscillation obtained by the trained ANN are as follows: the effects of pressure below 500 kPa are complex due to the influence of other parameters. F will increase with increasing mean mass flow rate under any conditions, and will decrease generally with an increase in relative amplitude. F will decrease initially and then increase with increasing inlet subcooling. The influence curves of mean mass flow rate on F will be almost the same when the period is shorter than 5.0 s or longer than 15 s. The influence of L/D will be negligible if L/D>200. It is found that the minimum number of neurons in the hidden layer is a product of the number of neurons in the input layer and in the output layer. 相似文献
33.
探讨了会计电算化条件下和传统手工会计条件下几种有重大差异的会计分录编制问题,指出实现会计电算化后,会计人员在编制会计分录时,既要遵循会计理论本身要求,又要考虑会计电算化软件的要求。 相似文献
34.
35.
In this paper, a process for 200 μm high-aspect-ratio micro-optical (HARM) structures fabricated by deep X-ray lithography
(DXRL) of polymethylislesuioane-based spin-on glass (SOG) thick films is presented. The SOG material used in the whole procedures
is polymethylsilsesquioxane (GR650), which is a kind of sol-gel derived material and can be cured at a reasonable low temperature
(75 °C). A technique to cast thick GR650 films was established in the overall process. After consolidation, the GR650 thick
films were machined to reach 200 μm uniformly. Then, as negative resists, the GR650 thick films were patterned directly by
DXRL. X-ray irradiated regions can be selectively retained with high structural resolution by development in an organic solvent,
such as methanol. Parameter screening was done to find minimum and maximum doses needed for patterning/cross-linking, to vary
development time, and to explore different film thickness. The whole process is a novel of technique to create HARM structures
based on SOG materials without using molds. This technique can be extended to considerably larger structural heights. Surface
and bulk compositions of the irradiated films were measured by XPS and Fourier transform infrared spectroscopy. Surface quality
by roughness testing system (WYKO RST) was investigated to fabricate the microstructure with a high-accuracy surface.
Received: 31 October 2001/Accepted: 23 January 2002
This work was partially supported by NSF/LEQSF (2001-04)-RII-02 grant “Micro/Nanodevices for Physical, Chemical and biological
Sensors”. 相似文献
36.
37.
首先提出在居住区规划中进行生态设计的理念及这一设计要依据的原則和生态学原理,然后概括出其涉及的主要内容与具体设计方法. 相似文献
38.
39.
在0.24~0.42mol/LHCl介质中,研究了17种络合剂对锆(Ⅳ)-m-NPF-CTMAB显色反应的影响。除乳酸、甘露醇、α-羟基异丁酸、氧代戊二酸和柠檬酸外,其余络合剂都使体系的吸光度降低。有乳酸和甘露醇存在下,有色络合物的表观摩尔吸光系数为1.30×105L·mol-1·cm-1。Zr(Ⅳ)在0~10μg/25mL符合比尔定律。方法用于铝合金中微量锆的测定,结果满意。 相似文献
40.
采用电化学腐蚀法制备多孔硅(PS),测量了PS在近红外光(800nm)激发下的光致发光(PL)谱和光致发光激发(PLE)谱,结果表明PS具有良好的上转换荧光特性,并随着存放时间的延长,在一定期了内峰值强度有明显的增强,这种非线性光这响应的增强,被认为与空间量子限制效应作用下局域束缚激子被激发有关,硅片初始电阻率赵低发光强度越大。 相似文献