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91.
以职业培训促进人才开发 总被引:1,自引:0,他引:1
经济社会的发展,不仅需要大量的专业技术人才,也需要大量的职业技术工人.以职业培训促进人才开发,树立培训是基础,鉴定是手段,就业是目的,素质提高是关键的思想. 相似文献
92.
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
93.
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
94.
95.
陈溯 《自动化与信息工程》1998,19(1):45-47
本文介绍了虚拟仪控的概念和LabVIEW图形程式语言的编程方法,性能特点,以及目前在广州地区的推广应用. 相似文献
96.
基础教育课程改革的浪潮滚滚而来,新课程体系有了重大的创新和突破.这场改革给教师带来了严峻的挑战,同时也给我们带来了不可多得的机遇. 相似文献
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During the solidification of the AZ91D-alloys, the Al8(Mn, Fe)5 phase is generally precipitated in the melt in advance of the precipitation of the primary α-Mg. The basic principle for manufacturing AZ91D-alloy slurries for semi solid forming is to use the Al8(Mn, Fe)5 precipitates as the heterogeneous nucleation sites for primary α-Mg phases. Microscopic analysis for the location of the Al8(Mn, Fe)5 precipitate explains that the Al8(Mn, Fe)5 precipitate is the effective heterogeneous nucleation site for the primary α-Mg phase. It was also observed that increase of the Mn content in the melt and the cooling rate below to the solid/liquid two-phase region resulted in smaller and more globular primary α-Mg due to the increase of heterogeneous nucleation sites. It was found that the average α-Mg diameter grew as a function of t0.278, where t is the holding time at the solid/liquid two-phase region. This would be attributed to the Ostwald type ripening and coalescence between primary α-Mg phases. The cooling rate below to the solid/liquid two-phase region, Mn content in AZ91D alloy, and the holding time and temperature affected on the quality of slurry. 相似文献
100.
郭惠玲 《武汉理工大学学报(材料科学英文版)》2018,33(3):559-565
A facile approach has been developed to synthesize Fe3O4@PAM (polyacrylamide) nanoparticles (NPs) with carboxyl groups on the surfaces by copolymerization with acrylamide and acrylic acid in Fe3O4 NPs aqueous suspension. Nitrilotriacetic acid (NTA) was conjugated to the magnetic NPs via well-known carboniimide chemistry using EDC and NHS. The Ni2+ ions loaded on the surface of NPs provide abundant docking sites for immobilization of His-tagged green fluorescent proteins (His-tagged GFP). The high magnetic property of Fe3O4@PAM@NTA-Ni2+ allows an easy separation of the NPs from solution under an external magnetic field, with high His-tagged protein binding capacity (42 μg protein/mg of NPs). The NPs can be recycled for at least four times without significant loss of binding capacity to proteins. These materials show great potential to separate His-tagged protein with low-cost purification at industrial scale. 相似文献