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81.
Fluorine: Edge‐Fluorinated Graphene Nanoplatelets as High Performance Electrodes for Dye‐Sensitized Solar Cells and Lithium Ion Batteries (Adv. Funct. Mater. 8/2015)
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82.
利用微分几何的方法,将非线性Hopfield神经网络在平衡点附近精确线性化,使之变换成线性系统。通过分析神经网络的n阶李导数,给出并证明了Hopfield神经网络的局部稳定性定理。定理表明,当神经网络满足精确线性化条件时,系统的可控矩阵的非奇异性充分决定了神经网络吸引子的局部稳定范围。 相似文献
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86.
导致金属氧化膜电阻器失效的主要因素是膜层结构变化、电解和接触部分老化。为了减少失效,改善电阻温度系数α,在生产实践中控制工艺参数及关键工序(镀膜、热处理、刻槽、涂漆)的质量,其中重点是镀膜。通过调整镀膜靶材,H靶:α从大于150×10-6℃-1调整在±60×10-6℃-1之内;F靶:α从大于200×10-6℃-1调整在±120×10-6℃-1之内,提高了金属氧化膜电阻器的可靠性。 相似文献
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A temperature-dependent model for long-channel silicon-on-insulator (SOI) MOSFETs for use in the temperature range 27 °C-300 °C, suitable for circuit simulators such as SPICE, is presented. The model physically accounts for the temperature-dependent effects in SOI MOSFETs (such as threshold-voltage reduction, increase of leakage current, decrease of generation due to impact ionization, and channel mobility degradation with increase of temperature) which are influenced by the uniqueness of SOI device structure, i.e. the back gate and the floating film body. The model is verified by the good agreement of the simulations with the experimental data. The model is implemented in SPICE2 to be used for circuit and device CAD. Simple SOI CMOS circuits are successfully simulated at different temperatures 相似文献
89.
超声波振动切削是一种新型的复合加工方法,其关键之一是在切削的有载状态下能否保持一定的振幅值,本文就中置式超声波振动切削系统的幅载特性进行了理论和实验研究。 相似文献
90.
Practical electrosynthesis of cuprous oxide powder was carried out on a laboratory scale in a cell specially constructed both with and without a diaphragm under the various operating conditions guided by the authors' previous research. The electrolysis was appraised in terms of the quality of the cuprous oxide product, the electrodissolution of the copper anode, and the SEM microstructure of the cuprous oxide powder. In a cell having a diaphragm, of which nylon fabric is the best, the optimal electrolysis operating conditions are: 250gl–1 NaCl, 0.1–1.0gl–1 NaOH, 500–1500Am–2, 80°C, perforated titanium sheet as the cathode, and around 3% cell volume of electrolyte circulation per minute. Under these conditions a product containing more than 97% cuprous oxide can easily be produced with very stable electrolysis and quite uniform dissolution of the copper anode. To eliminate the use of a diaphragm in the cell, the addition of sodium chromate, sodium dichromate, or calcium gluconate is effective in a sense, depending upon the requirements of the cuprous oxide product. For a product in which more than 95% cuprous oxide and no copper powder are required but a slightly higher content of chloride is allowable, sodium chromate and dichromate can be proposed for use with the former around 0.03–0.05gl–1 and the latter around 0.020–0.025gl–1, although the copper anode will not be perfectly evenly dissolved. For a product in which more than 97% cuprous oxide is demanded and a very small amount of copper powder is tolerated, calcium gluconate would be acceptable at around 4.5gl–1 with quite even dissolution of the copper anode. As to the auxiliary additives, hydrazine hydrate has a negative effect on the quality of the cuprous oxide product. Sucrose can cause a small increase in the chloride content but can make the particles of cuprous oxide more compact thereby increasing sharply its apparent density. Hydroxylamine hydrochloride is the best auxiliary additive which has a positive effect on the purity of the cuprous oxide product but produces no obvious change in the microstructure on the cuprous oxide particles. Even though most work has been concentrated on the electrolytic process, the subsequent processes are equally important: 65–70°C, distilled water for washing, benzotriazole in ethanol solution for stabilization of the cuprous oxide, and 100°C at a vacuum of less than 20mm Hg for drying seem to be satisfactory. A vacuum drying temperature of 55–60°C may be more appropriate to ensure against any oxidation of the product. 相似文献