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71.
The oxidation of Kovar alloy was investigated, the wetting and spreading behavior of hard and soft glasses on Kovar alloy were studed by using the sessile drop method, and the quality and the seal strength of glass-Kovar seals were tested. The experimental results indicated that the preoxidation of Kovar alloy for approximately 10 min at 700°C in air resulted in excellent adherence in glass-Kovar seals. The wetting and spreading behavior of glass on preoxidized Kovar alloy were superior to that on nonoxidized Kovar alloy. The wetting ability of ASF110 glass, at 950°C and 980°C in Ar and N2 atmospheres, was significantly superior to that of ASF200R and ASF700 glasses. The seal quality of the glass-preoxidized Kovar seal was superior to that of the glass-nonoxidized Kovar seal. The shear strength of the ASF110 glass-preoxidized Kovar seal, which was prepared at 980°C for 20 min in an Ar atmosphere, was approximately 3.9 MPa. 相似文献
72.
The defects of present methods of short-term numerical climate prediction are discussed in this paper, and four challenging
problems are put forward. Considering our under developed computer conditions, we should innovate in the approcuch of numerical
climate prediction on the basis of our own achievements and experiences in the field of short-term numerical climate prediction.
It is possibly an effective way to settle the present defects of short-term numerical climate prediction. 相似文献
73.
Based on the qualitative theory of atmospheric dynamical equations, a new method for simplifying equations, the operator constraint principle, is presented. The general rule of the method and its mathematical strictness are discussed. Moreover, the way that how to use the method to simplify equations rationally and how to get the simplified equations with harmonious and consistent dynamics is given. 相似文献
74.
Yuk-Man Leung Kar-Lok Wong Chia-Huei Lin Chia-Chia Chao Chun-Hsiao Chou Li-Yun Chang Siao-Wei Chen Tzu-Hurng Cheng Yueh-Hsiung Kuo 《Cellular and molecular life sciences : CMLS》2010,67(1):147-156
Voltage-gated K+ (Kv) channels exhibit slow or C-type inactivation during continuous depolarization. A selective pharmacological agent targeting
C-type inactivation is hitherto lacking. Here, we report that 6β-acetoxy-7α-hydroxyroyleanone (AHR), a diterpenoid compound
isolated from Taiwania cryptomerioides, can selectively modify C-type inactivation of Kv1.2 channels. Extracellular, but not intracellular, AHR (50 μM) dramatically
accelerated the slow decay of Kv currents and left-shifted the steady-state inactivation curve. AHR blocked Kv currents with
an IC50 of 17.7 μM. AHR did not affect the kinetics and voltage-dependence of Kv1.2 channel activation. Channel block by AHR was
independent of intracellular K+ concentration. In addition, effect of AHR was much attenuated in a Kv1.2 V370G mutant defective in C-type inactivation. Therefore,
block of Kv1.2 channels by AHR did not appear to involve direct occlusion of the outer pore but depended on C-type inactivation.
AHR could thus be a probe targeting Kv channel C-type inactivation gate. 相似文献
75.
针对工件到达时间与加工时间不确定,且存在紧急工件的并行机开放车间调度问题,以TWC(total weighted completion time)与TWT(total weighted tardiness)为优化目标,设计了一种集成FlexSim仿真模型与NSGA-Ⅱ算法的自适应动态调度方法。该方法以FlexSim模型仿真工件的生成和加工为基础,根据车间实时负荷确定动态调度周期,对紧急工件进行右移重调度,利用NSGA-Ⅱ算法生成双目标优化的调度方案。某晶粒拣选车间生产数据的实验结果表明,相较于利用规则的实时动态调度与固定周期重调度,提出的方法能够在最小化调度偏离度的同时获得满意解。 相似文献
76.
Ben-Chaung Wang Fang-Yi Chou Yung-Jaan Lee 《Systemic Practice and Action Research》2010,23(2):157-172
Chung-Sheng Community in Taoyuan City, Taiwan is a typical urban community. By adopting participatory action research, this study examines resident awareness regarding the feasibility of transforming Chung-Sheng Community into a sustainable community. Action research can help avoid constant “trial and error” in constructing sustainable communities and enhance process efficiency. Meanwhile, an active research approach can help communities better achieve sustainable development. Constructing a sustainable urban community requires energy, effective frameworks, and professional assistance. Achieving these requires a continuous and participatory action research process, and careful exploration of the awareness of community residents, which is the focus of this investigation. 相似文献
77.
Interdiffusion in the Fe2O3-TiO2 system was investigated by the diffusion couple method in the temperature range of 1323 to 1473 K. The diffusion concentration curves of Ti4+ cations were obtained by electron probe microanalysis, according to which the Boltzmann-Matano method optimized by Broeder was used to calculate the interdiffusion coefficients. The interdiffusion coefficients almost increased linearly with the mole fraction of Ti4+ cations increasing, and they were in the range of 10?12–10?11cm2·s?1. The increase of temperature could also lead to the increase of the interdiffusion coefficients at a constant concentration of Ti4+ cations. It was also found that the thickness growth of the diffusion layer obeyed the parabolic rate law. 相似文献
78.
79.
Zhi-yuan Chen Liu-zhen Bian Li-jun Wang Zi-you Yu Hai-lei Zhao Fu-shen Li Kuo-chih Chou 《矿物冶金与材料学报》2017,24(5)
The carbon deposition behavior on nickel particles was observed within the temperature range from 400 to 800℃ in a pure methane atmosphere.The topography,properties,and molecular structure of the deposited carbon were investigated using field-emission scanning electron microscopy (FESEM),temperature-programmed oxidation (TPO) technology,X-ray diffraction (XRD),and Raman spectroscopy.The deposited carbon is present in the form of a film at 400-450℃,as fibers at 500-600℃,and as particles at 650-800℃.In addition,the structure of the deposited carbon becomes more ordered at higher temperatures because both the TPO peak temperature of deposited carbon and the Raman shift of the G band increase with the increase in experimental temperature,whereas the intensity ratio between the D bands and the G band decreases.An interesting observation is that the carbon deposition rate is suppressed in the medium-temperature range (M-T range) and the corresponding kinetic mechanism changes.Correspondingly,the FWHM of the G and D1 bands in the Raman spectrum reaches a maximum and the intensities of the D2,D3,and D4 bands decrease to low limits in the M-T range.These results indicate that carbon structure parameters exhibit two different tendencies with respect to varying temperature.Both of the two group parameters change dramatically as a peak function with increasing reaction temperature within the M-T range. 相似文献
80.
Feng-hua Chen Yi-wen Wu Huan-hong Zhang Zhan-tu Long Xiao-xin Lin Ming-zhe Chen Qing Chen Yi-fan Luo Shu-Lei Chou Rong-hua Zeng 《矿物冶金与材料学报》2021,28(10):1675-1683
p-Benzoquinone (BQ) is a promising candidate for next-generation sodium-ion batteries (SIBs) because of its high theoretical specific capacity, good reaction reversibility, and high resource availability. However, practical application of BQ faces many challenges, such as a low discharge plateau (~2.7 V) as cathode material or a high discharge plateau as anode material compared with inorganic materials for SIBs and high solubility in organic electrolytes, resulting in low power and energy densities. Here, tetrahydroxybenzoquinone tetrasodium salt (Na4C6O6) is synthesized through a simple neutralization reaction at low temperatures. The four –ONa electron-donating groups introduced on the structure of BQ greatly lower the discharge plateau by over 1.4 V from ~2.70 V to ~1.26 V, which can change BQ from cathode to anode material for SIBs. At the same time, the addition of four –ONa hydrophilic groups inhibits the dissolution of BQ in the organic electrolyte to a certain extent. As a result, Na4C6O6 as the anode displays a moderate discharge capacity and cycling performance at an average work voltage of ~1.26 V versus Na/Na+. When evaluated as a Na-ion full cell (NIFC), a Na3V2(PO4)3 || Na4C6O6 NIFC reveals a moderate discharge capacity and an average discharge plateau of ~1.4 V. This research offers a new molecular structure design strategy for reducing the discharge plateau and simultaneously restraining the dissolution of organic electrode materials. 相似文献