摘要：在历史文化街区的建设中,借鉴楹联这种传统的景观意象表达方式,既是一种容易实现的手段,对于景观文化意蕴的表达以及审美体验的提升也具有积极价值。

摘要：脉冲喷射推进是海洋生物中普遍存在的一种游动方式,从乌贼喷射推进的游动方式中受到启发,基于电磁动态驱动原理,设计了一种仿乌贼喷射推进的软电磁机器鱼.其由柔软的机体外壳、软电磁线圈和软电磁驱动薄膜组成,能够在动态电磁力的作用下改变内部腔体体积而实现循环反复的喷射推进.本文研究了不同设计参数和激励电流对软电磁驱动薄膜的振动特性的影响,并通过实验测试了在不同控制电流的幅值和频率下机器鱼的水下推进力和游动速度.研究结果表明,机器鱼的最大平均推力为0.0784 N,机器鱼在动态电磁激励作用下能够达到37.3 mm/s (约0.62身长/s)的最大游动速度,具有优越的游动性能.

摘要：我国生活垃圾分类运输能耗高的问题一直未能根本解决。对该环节开展能耗分析是综合评价垃圾分类环境、经济效益的基础,也可为我国城市垃圾分类运输系统设计提供依据。基于分类垃圾性质与产生特征,结合运输车辆运行规律,构建了以居民区、办公区/商业区及学校为主要业态的3类典型城市区域分类垃圾直接运输,以及一级转运运输场景,并对各场景综合能耗进行核算。结果表明:不同典型城市区域生活垃圾分类运输单位能耗差异不显著[直运0.11~0.12 kgce/(t·km),转运0.06~0.08 kgce/(t·km)],分类运输较混合运输能耗增加77%~116%(直运)和25%~42%(一级转运),而转运操作对运输能耗的降低与运输距离负相关。对各垃圾组分而言,厨余垃圾运输能耗[直运0.09~0.10 kgce/(t·km),转运0.05~0.07 kgce/(t·km)]略低于其他垃圾和可回收物[直运0.11~0.13 kgce/(t·km),转运0.07~0.08 kgce/(t·km)],而有害垃圾运输能耗最高[直运0.21~0.30 kgce/(t·km),转运0.13~0.20 kgce/(t·km)]。

摘要：The design and synthesis of high‐performance and low‐cost electrocatalysts for the hydrogen evolution reaction(HER),a key half‐reaction in water electrolysis,are *** to their modest hydrogen adsorption energy,ruthenium(Ru)‐based nanomaterials are considered outstanding candidates to replace the expensive platinum(Pt)‐based HER *** this study,we developed an adsorption‐pyrolysis method to construct nitrogen(N)‐doped graphene aerogel(N‐GA)‐supported ultrafine Ru nanocrystal(Ru‐NC)nanocomposites(Ru‐NCs/N‐GA).The particle size of the Ru‐NCs and the conductivity of the N‐GA substrate can be controlled by varying the pyrolysis *** experiments reveal revealed that 10 wt%Ru‐NCs/N‐GA nanocomposites require overpotentials of only 52 and 36 mV to achieve a current density of 10 mA cm^(−2) in 1 mol/L HClO4 and 1 mol/L KOH electrolytes for HER,respectively,which is comparable to 20 wt%Pt/C *** from the ultrafine size and uniform dispersion of the Ru‐NCs,the synergy between Ru and the highly conductive substrate,and the anchoring effect of the N atom,the Ru‐NCs/N‐GA nanocomposites exhibit excellent activity and durability in the pH‐universal HER,thereby opening a new avenue for the production of commercial HER electrocatalysts.

摘要：根据封隔器坐封方式的不同,介绍了机械坐封、液压坐封压裂管柱的工作原理及特点;对不同坐封方式下的压裂管柱进行力学分析,建立了坐封前、坐封过程及压裂过程的力学模型。以实例研究在既定施工规模下优选压裂管柱封隔器的坐封方式,给出了平衡压力的确定方法。此研究为压裂管柱优化设计和封隔器坐封方式的合理选择提供了理论依据和分析手段,提高了压裂效果和成功率。