Plasmon enhancement for Vernier coupled single-mode lasing from ZnO/Pt hybrid microcavities

It is essential to develop a single mode operation and improve the performance of lasing in order to ensure practical applicability of microlasers and nanolasers.In this paper,two hexagonal microteeth with varied nanoscaled air-gaps of a ZnO microcomb are used to construct coupled whispering-gallery cavities.This is done to achieve a stable single mode lasing based on Vernier effect without requiring any complicated or sophisticated manipulation to achieve positioning with nanoscale precision.Optical gain and the corresponding ultraviolet lasing performance were improved greatly through coupling with localized surface plasmons of Pt nanoparticles.The ZnO/Pt hybrid microcavities achieved a seven-fold enhancement of intensity of single mode lasing with higher sidemode suppression ratio and lower threshold.The mechanism that led to this enhancement has been described in detail.     

二板式注塑机合模机构的振动测试

为提高大型二板注塑机合模机构的工作可靠性,对注塑成型完整周期过程中的注塑机动、定模板进行振动与冲击加速度测试,确定了振动信号中的低、高频成分的来源。低频振动是影响合模过程的主要振动信号,通过数字滤波和数值积分技术,评定了动、定模板的轴向振动加速度和最大摆动角度,为合模机构的减振优化和质量控制提供技术基础。     

Single-Atom Catalysts and Dual-Atom Catalysts for CO2 Electroreduction: Competition or Cooperation?

Developing highly active and selective electrocatalysts for electrochemical reduction of CO₂ can reduce environmental pollution and mitigation of greenhouse gas emission. Owing to maximal atomic utilization, the atomically dispersed catalysts are broadly adopted in CO₂ reduction reaction (CO₂RR). Dual-atom catalysts (DACs), with more flexible active sites, distinct electronic structures, and synergetic interatomic interactions compared to single-atom catalysts (SACs), may have great potential to enhance catalytic performance. Nevertheless, most of the existing electrocatalysts have low activity and selectivity due to their high energy barrier. Herein, 15 electrocatalysts are explored with noble metallic (Cu, Ag, and Au) active sites embedded in metal–organic hybrids (MOHs) for high-performance CO₂RR and studied the relationship between SACs and DACs by first-principles calculation. The results indicated that the DACs have excellent electrocatalytic performance, and the moderate interaction between the single- and dual-atomic center can improve catalytic activity in CO₂RR. Four among the 15 catalysts, including (CuAu), (CuCu), Cu(CuCu), and Cu(CuAu) MOHs inherited a capability of suppressing the competitive hydrogen evolution reaction with favorable CO overpotential. This work not only reveals outstanding candidates for MOHs-based dual-atom CO₂RR electrocatalysts but also provides new theoretical insights into rationally designing 2D metallic electrocatalysts.     

双腐蚀缺陷油气管道剩余强度分析

以X60双腐蚀缺陷油气管道为研究对象,借助ANSYS软件,分析双腐蚀缺陷半径和缺陷深度对其等效应力和剩余强度的影响。结果表明:随着轴向位置的增加,双腐蚀缺陷管道等效应力在屈服极限与抗拉极限之间变化;随着缺陷半径的增大,剩余强度呈增加的趋势,安全性增强;随着缺陷深度的增大,剩余强度呈减小的趋势,安全性降低。所得结论对于油气管道的腐蚀安全评价有一定的参考意义。     

外墙保温体系节能及其防裂机理研究

阐述了建筑物节能保温效果降低的主要原因是墙体裂缝,从抗裂的角度分析了外墙外保温的优势,并提出了外墙保温体系裂缝控制的原则和防护措施。     

新时期解决农村群体性事件的应然、实然和必然

近年来,我国农村群体性事件频频发生并呈现出螺旋上升态势。处于社会转型期的农村,其各种矛盾冲突提档升级,群体性事件频频见诸报端,愈演愈烈,不仅严重制约着社会主义和谐新农村建设的步伐,也给基层政府的治理提出了严峻考验。以新时期农村经济社会的发展趋势为时代背景,深度挖掘解决农村群体性事件的应然之义,探寻新时期农村群体性事件的实然之路,提出解决农村群体性事件的必然之策,为新时期农村群体性事件的政府治理提供理论依据。