中高压电子铝箔腐蚀系数的研究

分析比较了基于矩形凹槽模型、圆孔隧道模型、正立方孔隧道模型计算出的中、高压电子铝箔腐蚀系数与KDK公司(H100)形成箔实际腐蚀系数的关系。结果表明:中、高压电子铝箔真实理论极限腐蚀系数应介于正立方孔-圆孔理论极限腐蚀系数之间。中压电子铝箔(220～485 V)通过电蚀扩面提高化成箔比电容余地还很大,高压电子铝箔(>485 V)的实际腐蚀系数与理论极限腐蚀系数已经很接近,通过电蚀扩面提高比电容的余地较小。     

低压电子铝箔耐蚀性的研究与应用

采用对比实验,研究了腐蚀工艺对低压电子铝箔耐蚀性的影响。当腐蚀溶液中w(HCl)为15%～25%、w(H2SO4)为10%～20%,温度为85℃,电流密度为0.40A/cm2,腐蚀时间为3min时,铝箔腐蚀效果最佳,其耐蚀性数值(腐蚀前后质量差值与原光箔质量之比)为0.70%～0.83%。该工艺可迅速准确地判断低压电子铝箔的耐蚀性,平均每个样品所花时间仅为26min。     

Tomographic optical breast imaging guided by three-dimensional mammography

We introduce a modified Tikhonov regularization method to include three-dimensional x-ray mammography as a prior in the diffuse optical tomography reconstruction. With simulations we show that the optical image reconstruction resolution and contrast are improved by implementing this x-ray-guided spatial constraint. We suggest an approach to find the optimal regularization parameters. The presented preliminary clinical result indicates the utility of the method.     

Dissolution and re-crystallization processes in multiphase silicon stabilized tricalcium phosphate

Ultrasonically accelerated dissolution of multiphase silicon stabilized tricalcium phosphate powders in water or Earle’s balanced salt solution transforms the powders into needle-like calcium deficient apatite crystals with the c-axis (001) oriented along the needle. Ion exchange with the solution occurs primarily in the first hours of immersion. The transformation is driven by an interaction between the crystal surface and adsorbed water leading to the growth of crystallites which have the most stable surface configuration. First principles calculations of the surface energies of various hydroxyapatite surfaces with and without adsorbed water shows that depending on the ion concentrations in the fluid that determine the chemical potential of tricalcium phosphate, either Ca-rich (010) or stoichiometric (001) layers are the dominant surfaces. The higher the chemical potential, the more elongated in the (001) direction the crystallites become to minimize the total surface energy. The loss of a calcium Ca²⁺ compensated by the addition of two H⁺ is strongly favoured energetically on the (001) and Ca-rich (010) surfaces. A high concentration of excess Si at grain boundaries may be partly responsible for the rapid transformation of multiphase Si-TCP.     

纳米铝金属间化合物涂层的研究进展

总结了采用低温震动法快速制备纳米铝金属间化合物涂层的研究进展。归纳了该纳米涂层形成的规律和抗高温腐蚀的性能;分析了该纳米涂层的形成机理以及具有优异抗高温腐蚀性能的原因：展望了该纳米涂层的制备技术和涂层体系的发展前景。     

Micro-Crystalline Coatings of Co-Cr Dispersed with Y2O3 Deposited by Series Electro-Pulse Discharge

A new technique-series electro-pulse discharge (SEPD)-was developed as a kind of surface coating process. In this technique, both positive and negative poles of a pulse power were used as the depositing electrodes with the substrate alloy as an induction electrode. Micro-crystalline Co-Cr and Co-Cr dispersed with Y2O3 coatings were deposited on Fe-18Cr-SNi stainless steel surface by using Co30Cr alloy as the depositing electrodes. Oxidation at 950℃ in ambient air shows that these coatings greatly improve the oxidation resistance of the steel. The addition of dispersed Y2O3 nano-particles into the alloy coatings was found to further reduce the scaling rate and enhance the adhesion of oxide scales.     

阴极气膜微弧放电沉积ZrO2-Y2O3陶瓷涂层

采用阴极气膜微弧放电沉积制备ZrO2-Y2O3陶瓷涂层，利用水溶液中阴极气膜放电产生的等离子体的能量，使在阴极表面形成的沉积物直接烧结为陶瓷涂层。研究了沉积涂层的影响因素和涂层形貌及结构。SEM，EDS和XRD分析结果表明，获得的ZrO2-Y2O3陶瓷涂层表面光滑、与基体结合致密、成分和相结构均匀，是一种由Y2O3部分稳定的ZrO2陶瓷涂层。通过测试阴极气膜放电过程中电流随时间的变化以及电位在两电极间分布，分析了阴极气膜放电沉积陶瓷涂层的机制。     

国产电解电容器用铝箔的发展与展望

本文简述了电解电容器铝箔的技术要求,回顾了上世纪80年代以来国产电解电容器用铝箔生产的发展过程。目前,电解电容器用国产铝箔的生产获得了新的发展机遇,并已进入快速发展的阶段,但仍然面临着巨大的挑战,相关产业结构的调整、顺应国际市场向环保型转化、产品质量的检测系统的建立与改进等都是在深入进行高、新技术开发的同时还需面对的重要课题。动员社会科研开发力量是相关企业获得技术创新的重要途径,各级政府的积极引导与支持是国产电解电容器铝箔产业获得更大发展的重要保证。     

Oxidation Resistance of Fe-13Cr Alloy with Micro-Laminated （ZrO2-Y2O3 ） / （Al2O3-Y2O3 ） Films

Oxidationofmetalsoralloysathightemperatures canbetreatedasaspecialcaseofmetalliccorrosion,inwhichsolidphasesinteracteitherwithaliquid agentoragaseousagent.Toimprovetheresistance againsthigh temperatureoxidationandelectrochemical corrosionofmetals,thesurfa…     

Large-scale synthesis of copper nanoparticles by chemically controlled reduction for applications of inkjet-printed electronics

Copper nanoparticles are being given considerable attention as of late due to their interesting properties and potential applications in many areas of industry. One such exploitable use is as the major constituent of conductive inks and pastes used for printing various electronic components. In this study, copper nanoparticles were synthesized through a relatively large-scale (5?l), high-throughput (0.2?M) process. This facile method occurs through the chemical reduction of copper sulfate with sodium hypophosphite in ethylene glycol within the presence of a polymer surfactant (PVP), which was included to prevent aggregation and give dispersion stability to the resulting colloidal nanoparticles. Reaction yields were determined to be quantitative while particle dispersion yields were between 68 and 73%. The size of the copper nanoparticles could be controlled between 30 and 65?nm by varying the reaction time, reaction temperature, and relative ratio of copper sulfate to the surfactant. Field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) images of the particles revealed a spherical shape within the reported size regime, and x-ray analysis confirmed the formation of face-centered cubic (FCC) metallic copper. Furthermore, inkjet printing nanocopper inks prepared from the polymer-stabilized copper nanoparticles onto polyimide substrates resulted in metallic copper traces with low electrical resistivities (≥3.6?μΩ?cm, or ≥2.2 times the resistivity of bulk copper) after a relatively low-temperature sintering process (200?°C for up to 60?min).