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101.
电子接插件的快速连续电镀方法 总被引:1,自引:0,他引:1
介绍了适于电子接插件的快速连续电镀金、钯及Sn-Pb合金工艺的流程、操作要领等,对镀层的性能进行了分析比较,提出了快速电镀应解决的问题。 相似文献
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Effect of Electronic Properties of Catalysts for the Oxidative Coupling of Methane on Their Selectivity and Activity 总被引:4,自引:0,他引:4
The oxidative coupling of methane (OCM) to higher hydrocarbons may eventually become an interesting alternative for the chemical utilization of natural gas. Extensive studies have been conducted since the works of Keller and Bhasin [l] and of Hinsen and Baerns [2]. 相似文献
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In this study, we report a Ho2O3 electrolyte–insulator–semiconductor (EIS) device films deposited on Si substrates through reactive sputtering. The effect of thermal annealing (700, 800, and 900 °C) on the structural and surface properties of Ho2O3 sensing film was investigated by X-ray diffraction, X-ray photoelectron spectroscopy, and atomic force microscopy. We found that the EIS device with a Ho2O3 sensing film annealed at 800 °C exhibited a higher sensitivity of ∼57 mV/pH, a lower hysteresis voltage of 2.68 mV, and a smaller drift rate of 2.83 mV h−1 compared to those at other annealing conditions. This improvement can be attributed to the well-crystallized Ho2O3 structure and the large surface roughness. 相似文献
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108.
Yi Liu Toyoki Fujiwara Hiroshi Yukawa Masahiko Morinaga 《Solar Energy Materials & Solar Cells》2000,62(1-2)
Employing the DV-Xα molecular orbital method, lithium intercalation effect and alloying effect have been investigated on the electronic structures of spinel MxMn2−xO4 and LiMxMn2−xO4 (M=Ti, V, Cr, Mn, Fe, Co, Ni and Cu). It is found that the lithium intercalation induces the electron transfer from Li to the surrounding O ions, and enlarges the Mn-3d/O-2p band gap greatly. Such a modification of the oxygen electronic state is probably related to the electrochemical cell voltage. This lithium intercalation effect still holds even in the alloyed systems. However, the amount of transferred charges from M to O ions changes depending on the alloying element, M. So the alloying addition modifies the oxygen electronic state and influences the lithium intercalation process indirectly. 相似文献
109.
Quality assessment of honey is often related to its floral origin which is a complex task to evaluate. Traditional technique of floral assessment is made by melissopalynological method. However, this method is quite time consuming and also often operator dependent. Thus, the fallout is a large range of error in interpretation of the result and hence there is considerable demand for instrumental methods to assess the identification of pollen in honey. In this pursuit, an electronic tongue based on cyclic voltammetry is developed to discriminate honey samples based on their floral types and is described in this paper. The technique has been investigated using platinum as the working electrode and the resultant current from the potentiostat has been considered for data analysis. The use of principal component analysis (PCA) and linear discriminate analysis (LDA) proves to be useful in clustering honey samples. Finally, classification performances are investigated using back-propagation multilayer perceptron (BP-MLP) and radial basis function (RBF) neural network models for identification of different floral origin of honey. 相似文献
110.