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1.
《Ceramics International》2022,48(8):10420-10427
Precision glass molding (PGM) is a recently developed method to fabricate glass microgroove components. Lead glass is commonly used as an optical material due to its high refractive index and low transition temperature. A nickel-phosphorous (Ni–P) plated mold is traditionally employed in the PGM process for microstructures optics. However, leaded glass is subject to color change and can blacken during the PGM process, reducing the light transmittance of microgrooves. In this paper, an equation for the redox reaction between Ni and Pb is proposed, which is based on the diffusion of inner Ni atoms to the surface of the mold and the standard electrode potential of the Pb ions in leaded glass. A viscoelastic constitutive model of the glass is established to simulate the compression stress distribution during molding. Finally, the effects of molding pressure, molding temperature, and mold material on glass blackening are studied. The results show that the blackening of leaded glass is caused by Pb enriching the surface. The rise in molding stress and temperature increases the deformation of Ni–P plating, which promotes the diffusion of Ni atoms. By adding a titanium incorporated diamond-like carbon (Ti-DLC) coating, the deformation of the Ni–P plating during molding is suppressed, and the diffusion of Ni atoms can be prevented. In this way, the blackening of leaded glass can be prevented. 相似文献
2.
《Cities》2019
Residents' engagement in pro-environmental behavior is crucial in tackling the environmental challenges that cities face. Research shows that residents who are attached to their place of residence are more likely to engage in pro-environmental behavior and, consequently, place attachment has been prescribed as a pro-environmental policy. However, previous research has not explored which specific aspect of place attachment is most effective at promoting different types of pro-environmental behavior. Furthermore, in the context of big cities which typically host both natives and migrants, different resident groups may be attached to their places of residence due to different reasons. This implies that different types of place attachment policies may be required for each group of residents. Using survey data in Beijing, China, we find that the social bonding dimension of place attachment is most effective at promoting pro-environmental behavior and that this relationship is stronger for native born residents and those with longer residency length. We also find that the effect of place social bonding is stronger for high-effort than low-effort pro-environmental behavior. Our findings have implications for the design and implementation of place attachment policies for local authorities in Beijing and in other big cities where different groups of residents cohabit. Generally, our research results imply that place attachment policies that focus on promoting social connections amongst urban residents to their place of residence will be most effective. 相似文献
3.
研究了V以及BAT工艺、BQ&P工艺、DBAT工艺对中高碳(~0.6wt% C)纳米贝氏体钢等温转变过程中奥氏体碳富集的影响。为了分析不同热处理工艺时的组织转变,采用DIL805L型膨胀仪、X射线衍射仪(XRD)测量并计算残留奥氏体含量及其中碳含量,利用扫描电镜(SEM)分析了等温转变过程中试验钢显微组织形貌,并统计M/A岛含量及尺寸。结果表明:V对贝氏体转变有抑制作用,使残留奥氏体中碳富集速率变慢;3种热处理工艺下碳富集速率不同,BQ&P工艺和DBAT工艺的碳富集速率均大于BAT工艺,可利用BQ&P、DBAT工艺弥补合金元素V推迟相变的影响。 相似文献
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《中国有色金属学会会刊》2020,30(12):3347-3355
MnO2/MnO cathode material with superior Zn2+ storage performance is prepared through a simple physical mixing method. The MnO2/MnO nanocomposite with a mixed mass ratio of 12:1 exhibits the highest specific capacity (364.2 mA·h/g at 0.2C), good cycle performance (170.4 mA·h/g after 100 cycles) and excellent rate performance (205.7 mA·h/g at 2C). Analysis of cyclic voltammetry (CV) data at various scan rates shows that both diffusion- controlled insertion behavior and surface capacitive behavior contribute to the Zn2+ storage performance of MnO2/MnO cathodes. And the capacitive behavior contributes more at high discharge rates, due to the short paths of ion diffusion and the rapid transfer of electrons. 相似文献
6.
《中国有色金属学会会刊》2020,30(2):417-427
To experimentally determine the isothermal sections of Co−Mo−Zn ternary system at 600 and 450 °C, the equilibrated alloy and diffusion couple methods were adopted by using scanning electron microscopy coupled with energy-dispersive spectrometry, X-ray diffractometry and electron probe microanalysis. Experimental results show that there are six three-phase regions on the Co−Mo−Zn isothermal section at 600 °C and nine three-phase regions on the Co−Mo−Zn isothermal section at 450 °C. No ternary compound is found in these two isothermal sections. Both the maximum solubilities of Mo in the Co−Zn compounds (γ-Co5Zn21, γ1-CoZn7, γ2-CoZn13 and β1-CoZn) and that of Zn in ε-Co3Mo are no more than 1.5 at.%. The maximum solubilities of Zn in μ-Co7Mo6 are determined to be 2.1 at.% and 2.7 at.% at 600 and 450 °C, respectively. In addition, the maximum solubilities of Co in MoZn7 and MoZn22 are 0.5 at.% and 4.7 at.% at 450 °C, respectively. 相似文献
7.
As a symbol of sharing economy, ride-hailing services have spread to Asia, where various forms of services have been established according to the existing socio-technical regimes, including legal, policy, and environmental concerns. China, in particular, has accepted ride-hailing services by revising existing institutions. This study analyzes China’s acceptance of ride-hailing services in the socio-technical system context set up for legacy services. Simulation modeling, combined with transition theory and an agent-based model, is used to analyze the data. This study calculates consumer disutility based on mobility market share, reflecting consumer preference, and predicts the sustainability of ride-hailing services. The simulation results conclude that legalization and socio-technical context are of importance for sustainable mobility. 相似文献
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以北京地坛医院为例,从总平面规划的角度对传染病医院设计的特点进行了总结,得出几点经验。 相似文献
10.
“奢侈化”居住空间作为近年来不断出现的空间概念和形态,改变和丰富了传统意义上的居住模式和居住内容。通过对“奢侈化”居住空间的基本概念和空间环境特点分析,浅释了它目前作为一种现象的存在意义、需求层次和需求量的问题。 相似文献