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71.
介绍了精密钛箔带材产品技术要求、国内生产现状及生产工艺流程,简述了应用领域及前景,提出了加速发展我国精密钛箔带材的建议。  相似文献   
72.
As promising anodes for sodium-ion batteries, metal sulfides ubiquitously suffer from low-rate and high-plateau issues, greatly hindering their application in f...  相似文献   
73.
Industrial parks, characterized as a cluster of enterprises situated in one location to share common resources, have played an indispensible role in boosting regional economic and industrial development. However, further development has been impeded by the shortage of land space, especially for the construction of warehouses. This paper proposes the concept of Supply Hub in Industrial Park (SHIP) as a promising approach addressing this challenge. SHIP is defined as a public provider of warehousing and logistics services for manufacturing enterprises located within an industrial park. The research reported in this paper focuses on evaluating the value of freight consolidation, one of the typical benefits of applying the SHIP approach. Two mathematical models of the supply chain in a typical industrial park are formulated: with and without SHIP. Genetic Algorithm (GA) is applied for solving the two models, and sensitivity experiments are conducted for comparative analysis between the two scenarios. The computational results show that through consolidating shipments, SHIP brings benefits to the whole industrial park. Total cost savings resulted from the application of SHIP would increase with the size of the supply chain, the vehicle capacity, and the rates of fixed transportation costs and holding costs of finished products at manufacturers.  相似文献   
74.
基于最优乘子潮流估计的故障筛选与排序   总被引:1,自引:0,他引:1  
提出了一种用于电压稳定安全评估的快速故障筛选和排序方法。该方法从故障前的临界点出发,通过最优乘子潮流法计算得到的故障后边界点来估计故障后临界点,当初始点接近临界点,通过一次迭代即可满足所需的计算精度,从而快速地识别出非严重故障。对于严重故障和某些特殊情况的故障进行了分析并提出了解决办法,保证了对严重故障的估计精度。通过某一实际703节点系统算例验证了该方法的有效性。  相似文献   
75.
Based on strain-based design, high deformability X70 high strength pipeline steel with dual-phase microstructure has been developed, which can be laid in the seismic, the cold or the deepwater region. The results illustrated that the developed X70 steel has the stress-strain curve like round house and it shows good anti-transformation characteristic, high uniform deformation(≥10%), enhanced n-value(≥0.10), and the low yield-tensile ratio Y/T(≤0.85). The dual-phase microstructure of ferrite and bainite conta...  相似文献   
76.
The aim of this study was to evaluate the effects of a simulated porcelain-fused-to-metal (PFM) firing process on the surface, corrosion behavior, and cell culture response of two cobalt–chromium (Co–Cr) dental alloys. Two Co–Cr dental alloys were tested—a high and a low molybdenum (Mo)-containing alloys. Before PFM firing, as-cast alloy specimens were examined for their microstructure, surface composition, and hardness. Corrosion behavior was evaluated using electrochemical impedance spectroscopy tests. Mouse 3T3 fibroblasts were exposed indirectly to specimens and MTT cell proliferation assays were performed after 3 and 6 days. The cell culture medium exposed to specimens was analyzed for metal ion release. After firing, similar alloy specimens were examined for the same properties. The tests showed that the PFM firing changed both alloys’ microstructures and hardness values. After PFM firing, the corrosion resistance of the low Mo-containing Co–Cr alloy decreased statistically, which corresponded with a reduction of Cr and oxygen levels in the surface oxides via X-ray photoelectron spectroscopy. Also, the MTT assay of this alloy decreased significantly corresponding with an obvious increase of Co release after the firing. For the high Mo-containing Co–Cr alloy, the surface composition, corrosion resistance, and cell culture response were not significantly changed after PFM firing. The results suggested that the corrosion resistance and biocompatibility of the low Mo-containing Co–Cr alloy decreased after PFM firing, whereas the firing process had little effect on the same properties of the high Mo-containing Co–Cr alloy.  相似文献   
77.
Stress corrosion crack growth rates of 304L stainless steel after one-directionally warm-rolled along the longitudinal (L) direction were measured in oxygenated and deoxygenated pure water at 288 °C. The fracture mode is mainly intergranular in the Transverse-longitudinal (T-L) orientation specimen, while it is occasionally intergranular in the Longitudinal-transverse (L-T) orientation specimen. The crack growth rates in the T-L orientation are higher than those in the L-T orientation in both oxygenated and deoxygenated environments, which is related to the effective cracking growth path as the result of microstructural anisotropy and applied loading direction.  相似文献   
78.
介绍了以环戊烷为发泡剂的冰箱高压发泡模塑生产成套设备的安全设计原则和具体实施内容,重点介绍了环戊烷/多元醇预混系统、聚氨酯环戊烷高压发泡机和聚氨酯冰箱发泡模塑生产线的安全要点。  相似文献   
79.
以城、郊为界将北京公路绿化状况分为两部分,并进行了分析比较,从而找出两者现状差异,并根据效区公路绿化中的不足,从提高认识、加大投入、合理设计、科学养护4个方面找到解决问题的方法。  相似文献   
80.
对建筑工程施工中易被忽视的几种问题进行探讨,并提出了相应的预防措施.  相似文献   
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