摘要：The polysulfide shuttling and sluggish redox kinetics,due to the notorious adsorption-catalysis underperformance,are the ultimate obstacles of the practical application of lithium-sulfur(Li-S)*** carbon-based and transition metal compound-based material solutions generally suffer from poor catalysis and adsorption,respectively,despite the performance gain in terms of the ***,we have enhanced polysulfide adsorptioncatalytic capability and protected the Li anode using a complementary bimetallic carbide electrocatalyst,Co3 Mo3 C,modified commercial *** this demonstration,the potentials of bimetal compounds,which have been well recognized in other environmental catalysis,are also extended to Li-S *** with this modified separator,a simple cathode(S/Super P composite)can deliver high sulfur utilization,high rate performance,and excellent cycle stability with a low capacity decay rate of^0.034%per cycle at 1 C up to1000 *** at a high S-loading of 8.0 mg cm^-2 with electrolyte/sulfur ratio=6 m L g^-1,the cathode still exhibits high areal capacity of^6.8 m A h cm^-*** experimental analysis and the first-principles calculations proved that the bimetallic carbide Co3 Mo3 C provides more binding sites for adsorbing polysulfides and catalyzing the multiphase conversion of sulfur/polysulfide/sulfide than monometallic carbide Mo2 ***,the modified separator can be reutilized with comparable electrochemical *** also showed other bimetallic carbides with similar catalytic effects on Li-S batteries and this material family has great promise indifferent energy electrocatalytic systems.

摘要：Solar-driven vapor generation by localized solar heating of a photothermal material is an environmentally friendly approach for seawater desalination and wastewater *** this work,inspired by the leaf transpiration in nature,we designed a novel bionic leaf to realize highly efficient solar vapor *** leaf-inspired three-dimensional(3D)material structure had a hydrophilic polyvinyl alcohol(PVA)foam layer(equivalence to the mesophyll tissue layer in a leaf)with high porosity and low thermal conductivity,a photothermal polypyrrole(PPy)layer(equivalence to the chlorophyll layer in a leaf)coated on the PVA foam,and a micro/nano-scale porous hydrophobic surface layer(equivalence to the stomal layer in a leaf).The PVA network had microchannels for water transportation and reducing water evaporation enthalpy,the PPy layer absorbed and converted solar energy to heat water locally,and the hydrophobic porous surface layer enhanced the rate of vapor *** asfabricated vapor generator based on the bionic-leaf structure achieved an impressive high evaporation rate of 3.09 kg m^(−2) h^(−1) under one sun irradiation(1 kW m^(−2)).The prototype vapor generator desalinated and purified brine and seawater successfully under natural *** solar vapor generator based on the biomimetic structure provides a potential low-cost and highly efficient water purification technology to help mitigate the global water crisis using sustainable energy.

摘要：机翼前缘结冰会改变机翼的气动轮廓并影响整体的空气动力学性能.研究简化角冰冰形对翼型绕流流场结构的影响可以为飞机防冰设计提供有价值的参考.采用粒子图像测速技术,在低速直流风洞中对覆盖不同角冰冰形的翼型在不同攻角时的流场结构进行了详细的实验测量.实验对象包括三种简化的冰形和原始冰形.结果表明,在本研究范围内,覆盖简化冰形的翼型和覆盖原始冰形的翼型在流场参数上的最大差异为35.11%.与原始冰形相比,覆盖简化的角冰冰形的翼型流场中的分离泡距离翼型前缘和后缘更远.在三种冰形简化方法中,将冰角简化成矩形并在冰角之间添加抛物线的连接方式具有比较好的简化效果.在选定的两个区域中,这种简化冰形和原始冰形在翼型绕流流场的参数平均值的差异在14.88%之内.

摘要：本文提出了全面学习和相量粒子群相结合的方法用于解决限定固有频率约束下的空间结构优化问题.通过将相量理论和全面学习策略相结合以提高粒子群算法的效率.在优化的过程中,一个所谓的相角采用了周期正弦和余弦函数给定义速度的关键参数建模使得速度可以从所有粒子前一步的最佳位置中选取.这个方法不但实现了粒子们可以快速学习并且在少量的计算中进行了在作用力和固有频率约束下结构杆件的安全性评估和优化尺寸分布.提出的优化设计方法成功解决了一些工程应用结构的基准设计问题,这证明了本文方法相对于最新元启发方法的准确性和稳定性.

摘要：This vertically self‐pillared(VSP)structure extends the application range of traditional porous materials with facile mass/ion transport and enhanced reaction ***,we prepare a single crystal metal‐organic framework(MOF),employing the ZIF‐67 structure as a proof of concept,which is constructed by vertically self‐pillared nanosheets(VSP‐MOF).We further converted VSP‐MOF into VSP‐cobalt sulfide(VSP‐CoS2)through a sulfidation *** plays an important role in almost all battery technologies;for metallic batteries,lithium anodes exhibit a high theoretical specific capacity,low density,and low redox ***,during the half‐cell reaction(Li++e=Li),uncontrolled dendritic Li penetrates the separator and solid electrolyte interphase *** employed as a composite scaffold for lithium metal deposition,there are many advantage to using this framework:1)the VSP‐CoS2 substrate provides a high specific surface area to dissipate the ion flux and mass transfer and acts as a pre‐catalyst,2)the catalytic Co center favors the charge transfer process and preferentially binds the Li+with the enhanced electrical fields,and 3)the VSP structure guides the metallic propagation along the nanosheet 2D orientation without the protrusive *** these features enable the VSP structure in metallic batteries with encouraging performances.

摘要：Photosynthetic terpene production represents one of the most carbon and energy-efficient routes for converting CO_(2)into *** photosynthetic organisms,metabolic engineering has led to limited success in enhancing terpene productivity,partially due to the low carbon *** this study,we employed systems biology analysis to reveal the strong competition for carbon substrates between primary metabolism(e.g.,sucrose,glycogen,and protein synthesis)and terpene biosynthesis in Synechococcus elongatus PCC *** then engineered key“source”and“sink”***“source”limitation was overcome by knocking out either sucrose or glycogen biosynthesis to significantly enhance limonene production via altered carbon ***,a fusion enzyme complex with geranyl diphosphate synthase(GPPS)and limonene synthase(LS)was designed to further improve pathway kinetics and substrate *** synergy between“source”and“sink”achieved a limonene titer of 21.0 mg/***,the study demonstrates that balancing carbon flux between primary and secondary metabolism can be an effective approach to enhance terpene bioproduction in *** design of“source”and“sink”synergy has significant potential in improving natural product yield in photosynthetic species.

摘要：可被蓝光激发的高热稳定性红色荧光粉是制作高性能白光二极管(WLED)的关键材料.研究发现,Ce^(3+)掺杂的SrLaScO_(4)(SLO:Ce^(3+))荧光粉在440 nm激发下呈现峰值为640 nm的反常宽带红光发射.光谱学和结构分析证实Ce^(3+)离子在SLO中进入[LaO_(8)]多面体,产生强的晶体场劈裂和较大的Stokes位移,实现了比Eu^(2+)更低能量的红光发射.我们还设计并揭示了一种电荷转移相互作用的策略:在Sc^(3+)位置引入电负性较大的Ga^(3+),Ga^(3+)可以吸引更多邻位配合基团的电荷,以减少导带底部的电子占用而扩大带隙.Sc/Ga取代有效地抑制了热激活电离过程,使SrLa(Sc,Ga)O_(4):Ce^(3+)的热稳定性获得了显著提升,即在150℃的发光强度比(相对于20℃)从15%提升至31%.本研究为发现具有良好热稳定性的新型Ce^(3+)掺杂红色荧光粉提供了有效的设计原则.

摘要：脊髓损伤(SCI)后如何对中枢神经进行保护性治疗是临床面临的巨大挑战.SCI发生后,在损伤部位会产生大量高毒性的活性醛分子.这类分子会扩大氧化应激范围,加重炎症反应,进而导致严重的继发性损伤.因此,高效清除活性醛分子有望成为治疗继发性脊髓损伤的新策略.本文设计制备了一种侧链上含有酰肼基团的聚多肽(PPAH)材料,它可以通过消除活性醛分子减轻继发性脊髓损伤.实验结果表明,PPAH在体外和体内都显示了清除活性醛的能力,并且能够有效保护神经细胞免受毒性醛分子(如丙烯醛)引起的氧化损伤.在大鼠SCI模型中,PPAH能够有效抑制炎症、保护神经元和抑制脱髓鞘,最终促进SCI大鼠的后肢运动功能恢复.综上,作为一种新型的活性醛分子消除材料,PPAH在治疗SCI方面显示出良好的应用前景.

摘要：Optical control of exotic properties in strongly correlated electron materials is very attractive owing to their potential applications in optical and electronic ***,we demonstrate a vertical heterojunction made of a correlated electron oxide thin film VO_(2) and a conductive 0.05 wt% Nb-doped TiO_(2) single crystal,whose metal-insulator transition(MIT)across the nanoscale heterointerface can be efficiently modulated by visible light *** magnitude of the MIT decreases from ~350 in the dark state to ~7 in the illuminated state,obeying a power law with respect to the light power *** junction resistance is switched in a reversible and synchronous manner by turning light on and *** optical tunability of it is also exponentially proportional to the light power density,and a 320-fold on/off ratio is achieved with an irradiance of 65.6 mW cm^(-2) below the MIT *** the VO_(2) thin film is metallic above the MIT temperature,the optical tunability is remarkably weakened,with a one-fold change remaining under light *** results are co-attributed to a net reduction(~15 meV)in the apparent barrier height and the photocarrier-injection-induced metallization of the VO_(2) heterointerface through a photovoltaic effect,which is induced by deep defect level transition upon the visible light irradiance at low ***,the optical tunability is minimal,resulting from the quite weak modulation of the already metallic band structure in the Schottky-type junction above the MIT *** work enables a remotely optical scheme to manipulate the MIT,implying potential uncooled photodetection and photoswitch applications.

摘要：Rational design of low‐cost and efficient electrocatalysts for ethanol oxidation reaction(EOR)is imperative for electrocatalytic ethanol fuel *** this work,we developed a copper‐doped nickel oxyhydroxide(Cu‐doped NiOOH)catalyst via in situ electrochemical reconstruction of a NiCu *** introduction of Cu dopants increases the specific surface area and more defect sites,as well as forms high‐valence Ni *** Cu‐doped NiOOH electrocatalyst exhibited an excellent EOR performance with a peak current density of 227 mA·cm^(–2)at 1.72 V versus reversible hydrogen electrode,high Faradic efficiencies for acetate production(>98%),and excellent electrochemical *** work suggests an attractive route of designing non‐noble metal based electrocatalysts for ethanol oxidation.