摘要：The energy crisis and global warming become severe issues. Solar-driven CO2 reduction provides a promising route to confront the predicaments, which has received much attention. The photoelectrochemical（PEC） process,which can integrate the merits of both photocatalysis and electrocatalysis, boosts splendid talent for CO2 reduction with high efficiency and excellent selectivity. Recent several decades have witnessed the overwhelming development of PEC CO2 reduction. In this review, we attempt to systematically summarize the recent advanced design for PEC CO2 reduction. On account of basic principles and evaluation parameters, we firstly highlight the subtle construction for photocathodes to enhance the efficiency and selectivity of CO2 reduction, which includes the strategies for improving light utilization, supplying catalytic active sites and steering reaction ***, diversiform novel PEC setups are also *** exploited setups endow a bright window to surmount the intrinsic disadvantages of photocathode, showing promising potentials for future applications. Finally, we underline the challenges and key factors for the further development of PEC CO2 reduction that would enable more efficient designs for setups and deepen systematic understanding for mechanisms.

摘要：绝大多数工业工程控制仍然使用PID控制器,但由于它不易获得精确的数学模型和其非线性时变系统的性质,传统PID控制难以获得良好的控制品质、难以满足精确的控制要求。为了使PID控制器达到理想的控制效果,提出了一种基于改进蚁群算法的PID参数优化整定算法。该算法采用了信息素挥发系数和信息素强度自适应调整机制和动态更新策略,用以加速优化算法的收敛。该算法简单易行,更容易找到全局最优解,优化效率和性能明显提高。仿真实验结果表明,同现有的优化算法整定的结果比较,被控系统的超调量、调整时间等明显减少,动态特性、鲁棒性和稳定性等明显提高,进而验证了所设计算法的可行性和优越性。

摘要：二氧化锡(SnO_(2))具有高的理论比容量,有望作为下一代锂离子电池负极材料.然而,Sn向SnO_(2)的不可逆转化以及充放电过程中巨大的体积变化限制了其实际的应用.本文基于三维互连多孔氧化铝模板,设计合成了一种由内腔同时填充NiO和SnO_(2)纳米颗粒的碳管基元相互连接组成的三维碳管网格膜,可以直接作为自支撑的高性能锂离子电池负极.该复合框架利用了NiO和SnO_(2)纳米颗粒的协同作用,不仅能够促进Sn向SnO_(2)的可逆转变,提高首次库伦效率,而且还可以缓释充放电过程中SnO_(2)剧烈的体积变化.此外,相互连接的三维碳管框架可以负载大量NiO和SnO_(2)纳米颗粒,缩短Li+的扩散距离,并作为快速的电子传输通道.因此,这种独特的结构赋予了该电极超高的储锂容量和倍率性能在1 A g^(-1)循环200次后,比容量达到928.5 mA h g^(-1),并且在4 A g^(-1)的高电流密度下仍然具有633.5 mA h g^(-1)的比容量.总之,这种独特的一体化结构在锂离子电池等储能领域具有广阔的应用前景.

摘要：双金属纳米颗粒催化剂因其在众多化学反应中的广泛应用而备受人们关注.其催化性能与双金属颗粒的结构密切相关.在原子水平上理解其结构热稳定性对设计高稳定性双金属催化剂具有重要意义.本文利用选择性原子层沉积技术,在SiO_(2)载体上精准地构筑了Au@Pt与Au@Pd核壳型催化剂,其中Au核尺寸约为5.1 nm,Pt或Pd的壳层厚度均控制在两个原子层左右.使用谱学、电镜表征对比其在氢气氛围下的结构热稳定性,发现相较于Au@Pd/SiO_(2)核壳型催化剂,Au@Pt/SiO_(2)更难于向合金结构转变,展现出了更为优异的结构热稳定性.此外,550℃高温还原后,两种催化剂均维持其颗粒尺寸,无明显聚集现象,展现出优异的抗烧结性能.Au@Pt/SiO_(2)核壳型催化剂具备更好的结构热稳定性,可能是源于壳层Pt原子更高的熔点以及Au-Pt之间更小的晶格失配.该工作为理解双金属纳米颗粒在高温下的热力学行为的内在机制提供了参考.

摘要：In order to achieve a wheelchair lift function, this paper designs a tri-scissors mechanism. Through the so-called H-type transmission and L-type swing rod, the three scissors mechanisms lift in the same rate with only one liner motor while ensuring the stability of the lift. Finite element analysis in ANSYS is performed to verify the material strength. The control system with Sunplus SCM achieves the voice control of wheelchair walking and lifting.

摘要：Solar evaporation based on plasmonic metal nanoparticles(MNPs)is emerging as a promising ***,the fine structure of MNPs is unstable,and both the high temperature generated by intensive light and corrosive ions in water could damage *** performance will decline after recycling and long-time *** address these issues,we adopted a sponge-templating method for preparing sandwich-like nanoplates with the gold nanoparticles(Au NPs)confined in reduced graphene oxide(rGO)*** to the confinement effect,both the surface melting and ion diffusion were *** solar evaporator based on the sandwich-like nanoplates showed a high solar-vapor conversion efficiency of 85.2%under a high light intensity of 10 *** 30 times recycle of seawater desalination,the conversion efficiency scarcely *** sandwich-like nanoplates with enhanced thermal and chemical stability of Au NPs are promising in the practical application of seawater desalination.

摘要：Although remarkable progress has been witnessed in mimicking the nacre-like architecture in laboratory,it remains a great challenge for understanding the unique balancing mechanism of toughness and strength in biological materials. Here,taking advantage of the synergistic effect of different dimensional nanoscale building blocks,we fabricate nacre-like films that reconcile high strength and *** obtained ternary lamellar composite films are constructed by one-dimensional xonotlite nanowires and two-dimensional montmorillonite nanosheets with the assistance of poly（vinyl alcohol）. The ternary composite films show high strength（（241.8±10.2）MPa） and toughness（（5.85±0.46） MJ m^-3）,both of which are higher than that of the single nanofibrillar xonotlite network films or the binary montmorillonite/poly（vinyl alcohol） composite films. The excellent mechanical properties of the nacre-like ternary composite films are aroused by the synergistic toughening mechanism of the different dimensional building blocks. This strategy provides a facile approach to integrate the nacre-like composite films with potential applications in tissue engineering scaffold,strong air barrier coatings,and fire-retardant packing materials.

摘要：The development of cost-effective and highperformance electrocatalysts has been increasingly studied to mitigate upcoming energy and environmental *** and heterointerface engineering have played significant roles in the rational design of electrocatalysts and modulation of their electrocatalytic ***,the synergistic effect between amorphization and heterointerfaces has been scarcely *** a proof-of-concept attempt,we develop amorphous FeMo(a-FeMo)electrocatalysts with an abundance of heterointerfaces that are composed of amorphous components and evaluate their electrocatalytic performances toward the nitrogen reduction reaction and oxygen evolution reaction(OER).Benefitting from the synergistic effect between the amorphous nature of the a-FeMo electrocatalysts,which offer a high density of active sites,and significant electron redistribution at the heterointerfaces,the electrocatalysts exhibit a high Faradaic efficiency of 29.15%,an elevated yield rate of 71.78μg_(NH_(3)) mg_(cat.)^(-1) h^(-1) with long-term stability at a potential of-0.1V *** hydrogen electrode and excellent electrocatalytic activity toward the *** study provides a promising and effective method for the rational design of low-cost heterogeneous catalysts with desirable efficiency,selectivity,and stability.

摘要：In order to reduce nursing intensity and improve freedom of the elderly and the disabled, a multi-function nursing wheelchair which can switch chair to bed and realize many kinds of posture transformation is designed. This paper introduces the mechanical structure design （position adjustment mechanism and variable wheelbase mechanism） and control design of posture transformation unit of multifunctional nursing wheelchair.

摘要：联邦学习使得多个移动参与者在不透露其本地隐私数据的情况下联合训练全局模型。通信计算代价和隐私保护性能是联邦学习的关键基础问题。现有的基于秘密共享的联邦学习安全聚合机制仍然存在引入显著额外计算代价、隐私保护性能不足和应对参与者掉线能力脆弱等问题。本文致力于通过引入灵活高效的秘密共享机制解决上述问题。本文提出了两种新颖的隐私保护联邦学习方案,分别是基于单向秘密共享的联邦学习(FLOSS)和基于多发秘密共享的联邦学习(FLMSS)。与当前的相关工作相比,FLOSS通过动态设计秘密共享的内容和对象,在显著降低通信代价的同时保证高强度的隐私保护性能。FLMSS进一步降低额外计算代价并且能够提高联邦学习应对参与者掉线的鲁棒性,从而在隐私保护和通信计算代价之间取得令人满意的平衡。安全性分析和基于真实数据集的性能评估证明了本文提出的方案在模型准确度、隐私保护性能和通信计算代价方面的优势。