双金属导电金属有机框架材料Ni/Co-CAT的制备及其氧还原催化性能研究

以2,3,6,7,10,11 -六羟基三亚苯(2,3,6,7,10,11-Hexahydroxytriphenylene, HHTP)为有机配体, Ni、Co为金属中心, 通过水热法制备了对应的儿茶酚酯盐(Ni-catecholate、Ni-Co-catecholate, 以下简称Ni-CAT和Ni-Co-CAT). 对其进行表征后, 选用单室反应器装置搭建微生物燃料电池(Microbial fuel cell, MFC). 将Ni-CAT和Ni-Co-CAT与炭黑以3∶1的质量比混合后应用于MFC阴极催化氧还原反应(Oxygen reduction reaction, ORR). 结果表明, Ni-Co-CAT催化的MFC反应器性能最好, 其MFC反应器的最大输出电压和功率密度分别为310 mV和190 mW/cm², 与商业Pt/C的性能相当. Ni-Co-CAT催化MFC的极限电流密度为2.84 mA/cm², 优于Ni-CAT的2.18 mA/cm², 表明在Ni-CAT结构中引入Co后, MFC产电效能得到了提升. 主要原因是, Ni-Co-CAT与炭黑充分混合后, 具有了更高的孔隙率和比表面积, 其结构上的金属位点M-O₆ (M=Ni或Co)提供了更多的催化活性, 使Ni-Co-CAT具有最优的电化学催化性能.     

燃料爆炸抛撒成雾的实验与数值研究

为了合理设计云雾爆轰装置 ,对液体燃料爆炸抛撒规律作了实验与数值模拟研究。获得 6～ 2 5 0kgFAE装置云雾形成的若干重要实验数据。通过实验数据分析给出了云雾膨胀的相似律 ,并研究了爆炸抛撒过程中近场与远场阶段特性 :用一个简化的解析模型描述了液体燃料的近场膨胀 ,给出了液体燃料在加速阶段的极限速度 ;用数值方法研究了远场云雾的物理特性 ,给出了云雾速度场及云雾内部燃料浓度与燃料蒸汽浓度的分布。     

Hydrothermal-Induced Formation of Well-Defined Hollow Carbons with Curvature-Activated N−C Sites for Zn–Air Batteries

Metal-free carbons have been regarded as one of the promising materials alternatives to precious-metal catalysts for oxygen reduction reaction (ORR) due to their high activity and stability. In this paper, well-defined N-doped hollow carbons (NHCs) are firstly synthesized by using an ammonia-based hydrothermal synthesis that is environmentally friendly and suitable for mass production in industry and a commercial black carbon as raw material. Moreover, the shell thickness of the NHCs can be easily tuned by this hydrothermal strategy. Zn–air battery test results reveal shell thickness-dependent activity and durability for ORR over the NHCs, which exceeds that obtained by commercial Pt/C (20 wt %). The enhanced battery performance can be attributed to the curvature-activated N–C moieties on the hollow carbon surface, which served as the main active sites for ORR as evidenced by DFT calculations. The proposed approach may open a way for designing curved hollow carbons with high graphitization degree and dopant nitrogen level for metal–air batteries or fuel cells.     

基于混合方法的工作乐趣分类模型构建及其效用的实证研究

本文采用混合研究的方法,分析目前两岸企业工作乐趣的开展类型和效果。在构建类型学概念模型基础上,修订中华工作乐趣测量量表并检验不同乐趣活动对员工的绩效影响差异。数据分析结果表明社交型、放松型、辅助型和福利型乐趣的四类结构信效度良好,但不同类型乐趣对员工满意度、任务绩效和组织公民行为的影响存在明显差异。     

劈尖干涉条纹变形原因的研究

介绍了劈尖干涉条纹变形原因的查找方法和指导该实验采取的教学方法；论述了在实验教学过程中注重发挥教师指导作用的必要性。     

重力加速度的正确测量和计算

本文介绍了用粘滞阻力修正法和粘滞阴力互相抵消法来精确地测量重力加速度。     

Iron‐catalyzed one‐pot oxidation/Knoevenagel condensation reaction using air as an oxidant

A green and highly efficient iron‐catalyzed one‐pot oxidation/Knoevenagel tandem reaction for the synthesis of α, β‐unsaturated nitriles from secondary alcohols and malononitrile has been achieved. The reaction performed under mild conditions with air as an oxidant, and provided the corresponding oxidation/Knoevenagel prudocts in good to excellent yields within short times avoiding the use of noble metal catalysts and bases. Remarkably, water is the only byproduct in this methodology. The reaction could be performed on a gram scale under the standard reaction conditions.     

Sustainable energy storage – with hot air,or cold air or liquid air

In memory of Sir David John Cameron MacKay FRS FInstP FICE (22 April 1967 – 14 April 2016). David was passionate about sustainable energy. One key element for sustainable energy is energy storage. As a small tribute, this article presents a review from a physics perspective of the thermodynamics of compressed air energy storage. Firstly, I treat adiabatic compressed air energy storage, where the heat of compression of the air is kept in the compressed air. Then I discuss improvements that can be made by combining compressed air energy storage with external heat stores. Next, I address isothermal compressed air energy storage, where the temperature is allowed to equilibrate with the environment. In each case, I consider two scenarios: underground caverns and underwater airbags. Finally, I address the case where the air is compressed and cooled so much that it liquifies. Throughout, I explain that the real point is to store available work, called exergy in the engineering community, rather than energy. Although my treatment is mostly from the ideal point of view of quasistatic processes, I give some pointers to technological implementations of the various methods and to some references on their thermodynamic efficiencies.