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91.
硅通孔(Through silicon via)的互连技术是3D IC集成中的一种重要工艺。报道了一种高深宽比的垂直互连穿透硅通孔工艺,其通孔的深宽比达到50以上;研究了利用钨填充硅通孔的一些关键工艺,包括阻挡层淀积工艺和钨填充工艺,分析了不同填充工艺所造成的应力的变化。最后获得了一种深宽比达到58∶1的深硅通孔无缝填充。  相似文献   
92.
针对当前城市供水调度监控点分布范围广、数量多、距离远的现状,提出了一种基于GPRS技术的城市供水调度监控系统的设计和实现方法。具体描述了监控现场的硬件连接;同时对该技术的应用前景进行了展望。  相似文献   
93.
利用扫描电镜(SEM)、台阶仪、X射线衍射仪(XRD)、透射电镜(TEM)、显微硬度仪对W6Mo5Cr4V2钢经强流脉冲离子束(HIPIB)辐照前后试样的表面形貌、粗糙度、表层的组织结构及硬度进行了分析,探讨了"熔坑"和硬度"多峰"态形成的原因.结果表明,试样表面粗糙度随辐照次数的增加有所减小;辐照过程使该钢体心立方的马氏体α'-Fe向面心立方的奥氏体γ-Fe转变,碳化物溶解,马氏体溶碳量增大且晶粒细化,点阵畸变度增大,使W6Mo5Cr4V2钢表面硬度有较大的提高.  相似文献   
94.
W / Cu functionally gradient materials (FGMs) containing 1%La_2O_3 and 1%TiC were prepared using graded sintering under ultra-high pressure (GSUHP). The specimens have been found to exhibit low porosity (11.57% and 11.35%, respectively). Shearing strength of the specimens between layers is good. Moreover, the specimens have still demonstrated good performance in testing thermal-shock resistance. When power density of laser is 200MWm~(-2), the specimens have been tested for thermal-shock resistance (1000 times); the specimens that contained 1%La_2O_3 were not subjected to damage, whereas those that contained 1%TiC began to crack. Finally, effect of additives on thermal-shock resistance was also preliminarily discussed.  相似文献   
95.
96.
党世红 《电子设计工程》2012,20(21):138-140
为了对实际信号进行监测,设计了以W77E58微控制器为核心的多路数据采集系统,介绍了系统总体结构,阐明了模拟量采集的硬件和软件设计方法,给出了具体的电路图和软件程序,经实际测试表明,该系统具有采集精度高、功耗低、抗干扰能力强、通用性好的特点。  相似文献   
97.
Gypsum boards form a very large part of the building walls and ceilings finishing market. However, they have poor screw-withdrawal resistance, low hardness and are highly sensitive to moisture. The objective of this study was to determine whether it is possible to make wood-cement particleboards of the same density as gypsum boards while avoiding these drawbacks.Wood-cement particleboards were made by pouring the wood-cement paste in a mould. This was made possible by adding a viscosity modifying mixture to the mixing water and a set accelerating mixture to improve wood/cement compatibility. The mechanical properties and surface quality of the wood-cement particleboards were improved by using, on the board surfaces, paper sheets that were the same as those used on gypsum boards.The average specific gravity of the wood-cement particleboards was the same as gypsum boards, at 0.7. The average bending modulus of rupture obtained for the wood-cement particleboards was 10 MPa in the finishing paper principal direction and 5 MPa in the other direction compared to 5.5 MPa and 1.6 MPa respectively for gypsum boards. The average screw-withdrawal resistance of wood-cement particleboards was 570 N, that is, 1.7 times higher than for gypsum boards.  相似文献   
98.

K416B Ni-based superalloy with high W content has good high temperature properties and low cost, which has a great development potential. To investigate the room temperature tensile property and the deformation feature of K416B superalloy, tensile testing at room temperature was carried out, and optical microscopy (OM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to analyze the deformation and damage mechanisms. Results show that the main room temperature tensile deformation features of the K416B nickel-based superalloy are dislocations slipping in the matrix and shearing into γ′ phase. The <110> super-dislocations shearing into γ′ phase can form the anti-phase boundary two coupled (a/2)<110> partial-dislocations or decompose into the configuration of two (a/3)<112> partial dislocations plus stacking fault. In the later stage of tensile testing, the slip-lines with different orientations are activated in the grain, causing the stress concentration in the regions of block carbide or the porosity, and cracks initiate and propagate along these regions.

  相似文献   
99.
金属W是核聚变反应堆中面向等离子体部件的主要候选材料。服役期间,钨部件需要承受高温、高通量聚变反应中子轰击带来的辐照级联损伤。这些损伤主要表现为高浓度的点缺陷及团簇。它们与氢氦等离子体、嬗变反应的多种产物相互作用,导致辐照硬化、韧脆转变温度升高、导热能力下降等问题。本文围绕金属W的辐照级联损伤,基于显微缺陷实验表征与材料多尺度模拟计算,系统总结了辐照缺陷的产生、演化与热回复行为及作用机制。这些信息反映了材料中辐照缺陷特征的统计规律,构成定量描述微观损伤组织随时间尺度与空间尺度变化的依据,有利于钨部件性能的预测、服役可靠性评价以及未来新型材料部件的研发。  相似文献   
100.
Effects of surfactant concentration, antioxidants with different polarities, and chelator type on the oxidative stability of water‐in‐stripped walnut oil (W/O) emulsions stabilized by polyglycerol polyricinoleate (PGPR) were evaluated. The formation of primary oxidation products (lipid hydroperoxides) and secondary oxidation products (hexanal) decreased with increasing PGPR concentrations (0.3–1.0 wt% of emulsions). Excess surfactant might solubilize lipid hydroperoxides out of the oil–water interface, resulting in the decreased lipid oxidation rates in W/O emulsions. At concentrations of 10–1000 μM, the polar Trolox demonstrated concentration‐dependent antioxidant activity according to both hydroperoxide and hexanal formation. The antioxidant efficiency of the non‐polar α‐tocopherol was slightly reduced at the higher range of 500–1000 μM based on hydroperoxide formation. Both ethylenediaminetetraacetic acid (EDTA) and deferoxamine (DFO) at concentrations of 5–100 μM reduced the rates of lipid oxidation at varying degrees, indicating that endogenous transition metals may promote lipid oxidation in W/O emulsions. EDTA was a stronger inhibitor of lipid oxidation than DFO. These results suggest that the oxidative stability of W/O emulsions could be improved by the appropriate choice of surfactant concentration, antioxidants, and chelators.  相似文献   
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