基于FPGA的RTL级USB2.0协议层设计与实现

文中重点阐述了用VerilogHDL语言对USB2.0协议层关键模块的RTL级设计和验证工作,并在XILINX ISE软件平台上进行了FPGA综合。通过在ModelSim6.1上仿真和ISE7.1上综合,结果表明本文设计的USB协议层模块是正确的。     

GexSi1—x／Si应变层超晶格的结构特性与器件应用

近年来,Ge_xSi_(1-x)/Si 应变层超晶格的研究日渐活跃与成熟。本文试从半导体物理与器件应用的角度出发,着重介绍了这种超晶格的各种结构特性,并简要评述了以 Ge_xSi_(1-x)/Si 异质结形成的各种新型半导体器件的研究进展。     

盐雾腐蚀对不同封装形式集成电路性能的影响

通过分析塑料封装、陶瓷封装、玻璃封装和金属封装集成电路的材料成分,得出它们抵抗盐雾的腐蚀能力。根据市场的使用情况,选用塑封、陶封、玻封三种封装形式的集成电路按照6种不同的试验条件进行盐雾试验。文章通过对试验后的结果进行比较和分析,得出在正常盐雾腐蚀条件下, 它们性能受到影响的大小;在不同盐雾溶液和不同的温度条件下,陶瓷封装电路的性能也发生了变化。最后对塑料封装、陶瓷封装、玻璃封装电路的抗盐雾腐蚀能力进行了总结。     

关于0Cr13/SA-387Gr11Cl复合板复层产生锈迹和裂纹的原因及预防措施

本文对0Cr13-SA-387Gr11Cl复合板复层产生锈迹、裂纹的原因进行了分析探讨,并提出了预防措施。     

Influence of phosphate species on green rust I transformation and local structure and morphology of γ-FeOOH

To clarify the role of phosphate in the formation of corrosion products, the transformation of GRI(Cl⁻) with the addition of phosphate was characterized through XRD, TEM, and solution analysis. Electrochemical analysis showed that the transformation of GRI(Cl⁻) was delayed and the size of the final products, i.e., γ-FeOOH was reduced in the phosphate added case. X-ray absorption spectroscopy indicated that the neighboring Fe–Fe coordination number of FeO₆ octahedral unit in γ-FeOOH was decreased. These effects of phosphate are attributed to its adsorption on GRI(Cl⁻) and nucleated γ-FeOOH that prevented particle growth during oxidation process.     

Crystallisation of nanohybrids of poly(ϵ-caprolactone) and hydrotalcites containing antimicrobial species

Abstract

New composites of poly(?-caprolactone) containing Zn/Al hydrotalcites [layer double hydroxide (LDH)] and ‘active’ antimicrobial anions (benzoate, dichlorobenzoate, o-hydroxybenzoate and p-hydroxybenzoate) prepared with two different techniques have been characterised through differential scanning calorimetry and dynamic mechanical analysis. The method of preparation of the samples has a strong influence on the dispersion of the nanolayers within the polymeric matrix, and, in turn, on the crystallisation kinetics: in fact, the samples prepared by high energy ball milling crystallise much faster than those prepared by casting. The different ‘active’ anions strongly affect the value of the LDH interlamellar distance, which, in turn, affects their capacity of dispersion in the polymer. As a consequence of the different kinds of dispersion, the sample containing benzoate LDH or dichlorobenzoate LDH crystallises faster than that containing p-hydroxybenzoate LDH. Such results are of great importance in the definition of processing and use conditions of such materials of potential interest in food ‘active’ packaging.     

Characteristics of the Thrust Bearing with Accelerating Slider

Thrust bearing characteristics are examined in the motion generated by the accelerating slider. The selected case is the situation where the fluid within the lubricating film initially is at rest and at time zero the infinitely long slider assumes a velocity which is a function of time. Numerical solutions to the governing differential equations are obtained for the case of constant but arbitrary acceleration and for the case of acceleration proportional to time. The corresponding previously published analytical solutions are compared with those numerical results.     

Role of zinc compounds on the formation, morphology, and adsorption characteristics of β-FeOOH rusts

To simulate the corrosion of galvanized steel in marine zone, β-FeOOH was prepared by aging the FeCl₃ solutions containing ZnCl₂ and zinc rusts such as ZnO and zinc hydroxychloride (Zn₅(OH)₈Cl₂·H₂O:ZHC). Adding ZnCl₂, ZnO, and ZHC inhibited the crystallization and particle growth of β-FeOOH and the inhibitory effect was in order of ZHC ≈ ZnO > ZnCl₂. The adsorption of H₂O and CO₂ was suppressed by adding ZnCl₂, ZnO, and ZHC. These results imply that the rust formed on galvanized steel in marine environment is more compact, amorphous, and hydrophobic in nature which may lead to improve the corrosion resistance.     

A proposal to evaluate the amount of corroded iron converted into adherent rust in steels exposed to corrosion

To calculate the amount of iron corroded from the steels that form part of the adherent rust, α, we propose a procedure that considers mass measurements and the use of spectroscopic techniques to estimate the relative iron phase abundances. We derived an equation to calculate α and evaluate it for carbon steels (CS) and weathering steels (WS) exposed to accelerated outdoor corrosion tests. The values of α are estimated at 0.93 and 0.76 for CS and WS after 2 years of exposure, respectively. The relative iron phase abundances pointed out to a non-protective and active type of rust.