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61.
Most of users are accustomed to utilizing virtual address in their parallel programs running at the scalable high-performance parallel computing systems. Therefore a virtual and physical address translation mechanism is necessary and crucial to bridge the hardware interface and software application. In this paper, a new virtual and physical translation mechanism is proposed, which includes an address validity checker, an address translation cache (ATC), a complete refresh scheme and many reliability designs. The ATC employs a large capacity embedded dynamic random access memory (eDRAM) to meet the high hit ratio requirement. It also can switch the cache and buffer mode to avoid the high latency of accessing the main memory outside. Many tests have been conducted on the real chip, which implements the address translation mechanism. The results show that the ATC has a high hit ratio while running the well-known benchmarks, and additionally demonstrates that the new high-performance mechanism is well designed. 相似文献
62.
为研究多物理场耦合粉末成形技术的低温超快速致密化成形机理,采用多物理场耦合粉末成形技术制备了微型铜齿轮。对铜粉末在600℃烧结过程的动力学曲线进行了分析,观察铜粉末分别在300℃、500℃和600℃烧结时试样断口的微观形貌,同时针对铜粉末烧结过程中的电流密度分布和温度场分布进行了数值模拟。研究发现,多物理场耦合粉末成形技术快速升温过程中,电场和热场在粉末颗粒中分布极不均匀,粉末颗粒接触处的电流密度和温度均远远高于颗粒其它位置的电流密度和温度,为此首次提出了“电热聚焦效应”。结果表明,电场和热场耦合并在颗粒接触点处高度聚焦产生的电热聚焦效应是多物理场耦合粉末成形过程中粉末材料实现低温超快速致密化成形的重要原因。 相似文献
63.
Mario Schmidt 《化学,工程师,技术》2021,93(11):1707-1716
The extraction of raw materials is associated with energy input and CO2 emissions. What is obvious for extraction from mining, however, also applies to recycling. Mostly, recycling is preferred for reasons of climate protection or because of the geological scarcity of raw materials, which is controversially discussed. While in mining, the declining ore grade is a driver for the energy demand, in case of recycling it is the dissipation of materials into products or waste. As concentration decreases, the effort required also increases disproportionately. The “closing the loop” metaphor of Circular Economy is therefore inappropriate in its stricter meaning. It is rather about optimizing the overall system and finding the optimal recycling rate. However, first, it must be clarified what the political goals for Circular Economy are. 相似文献
64.
The time dependency of the amounts of corrosion products and co-existing adsorbed water on copper in humid air containing SO2 was estimated from a series of in situ time-resolved IR-RAS spectra on the basis of the relations between the band intensities and the mass changes of the corrosion products, which were determined by simultaneous measurement of IR-RAS and QCM. The amounts of both corrosion products increased slowly at the initial stage and later increased rapidly. Although the relative humidity was kept constant, the amount of adsorbed water increased nearly the same behavior as that of corrosion products in the stage of relatively small amounts of corrosion products and later increased rapidly when the amounts of corrosion products increased. In humid air without SO2, sulfite gradually decomposed and some of it changed into sulfate. 相似文献
65.
2—巯基苯并噻唑在铜表面的吸附状态 总被引:4,自引:0,他引:4
在pH值大于6时,2-巯基苯并噻唑(MBT)在银和铜表面具有相同的吸附状态;随溶液pH值降低,部分吸附的硫醇离子逐渐异构化为硫酮,破坏了MBT平面吸附层。在pH值高于3时,MBT在铜表面仍然以其分子平面平行于表面,起到阻挡侵蚀分子的作用,由此可知在弱碱性溶液中它对于铜有更的保护效果。 相似文献
66.
A mechanism of formation of copper nanoparticles is proposed for alkaline etching of a sputtering-deposited Al-30 at.%Cu alloy, simulating the equilibrium θ phase of 2000 series aluminium alloys. Their formation involves enrichment of copper in the alloy beneath a thin alumina film, clustering of copper atoms, and occlusion of the clusters, due to growth of alumina around the clusters, to form nanoparticles. The proposed mechanism is supported by medium energy ion scattering, Rutherford backscattering spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy of the alloy following immersion in the sodium hydroxide solution, which disclose the enrichment of copper and the generation of the nanoparticles in the etching product of hydrated alumina. The generation of the nanoparticles is dependent upon the enrichment of copper in the alloy in a layer of a few nanometres thickness, with no requirement for bulk de-alloying of the alloy. 相似文献
67.
将自蔓延高温合成技术与离心铸造技术结合,开发了陶瓷内衬复合铜管技术,可在铜管内表面涂敷耐磨性和耐蚀性优良的陶瓷涂层。为提高陶瓷涂层致密度、韧性和结合强度,研究了添加剂的影响,结果表明,在铝热剂中加入SiO2、CrO3可提高致密度,加入N2B4O7可提高结合强度,加入ZrO2可提高断裂韧性。陶瓷内衬复合铜管应用于管坯结晶器,可提高使用寿命,降低成本。 相似文献
68.
The contact areas between Cu and Ta of a Cu interconnect can be susceptible to galvanic corrosion during chemical mechanical planarization (CMP) in polishing slurries capable of supporting ionic conduction. In the present work, we probe this effect at a partially Cu-covered Ta disk, by combining electrochemical impedance spectroscopy with potentiodynamic polarization and galvanic current measurements in two slurry solutions commonly used in CMP of Ta and Cu. The results of these measurements are compared with those for a Cu disk and a (Cu-free) Ta disk. The impedance data for the Cu-decorated Ta sample show negative impedance values at certain regions of the impedance spectra, whereas the individual Cu and Ta electrodes are free of this effect. The results are examined and explained from considerations of galvanic corrosion at the Ta/Cu bordering regions in contact with the slurry liquid. 相似文献
69.
The self-assembled monolayers (SAMs) of a series of substituted benzenethiol (BT) molecules, X-C6H4-SH (where X = meta-NH2, ortho-NH2, para-NH2, para-NHCOCH3, para-F, para-CH3 and para-CH(CH3)2), have been prepared by adsorption from a solution onto a fresh copper (Cu) surface pretreated by a nitric acid etch. The corrosion inhibition efficiency of the modified Cu surfaces in a sulfuric acid solution was investigated by electrochemical characterization. The protection afforded by the substituted functional groups on BT is strongly influenced by the type and the position of the substituent on the benzene ring. BT molecules without any substituent group on the ring are ineffective corrosion inhibitors, indicating that the chemical configuration is the key factor in determining the efficacy of the SAMs as barriers to electrochemically corrosive ions. It is further proposed that the steric hindrance offered by the substituted group in the SAMs plays a very important role in determining its barrier properties. 相似文献
70.
介绍了易门铜冶炼厂烟气制酸系统的技术改造工程.从工艺流程、设备复核、工艺参数、设备配置等方面阐述了技改的过程. 相似文献