摘要：The overall water splitting for hydrogen production is an effective strategy to resolve the environmental and energy crisis. Here, we report a facile approach to synthesize the Ir-based multimetallic, hierarchical, double-coreshelled architecture(HCSA) assisted by oil bath reaction for boosting overall water splitting in acidic environment. The Ir Ni Cu HCSA shows superior electrocatalytic activity for hydrogen evolution reaction(HER) and oxygen evolution reaction(OER), which are comparable to commercial Pt/C and better than IrO2. The Ir Ni Cu HCSA exhibits remarkably catalytic efficiency as bifunctional catalyst for overall water splitting where a low cell voltage of 1.53 V is enough to drive a current density of 10 mA cm^-2 and maintains stable for at least 20 h. The presented work for the design and synthesis of novel Ir-based multimetallic architecture paves the way for highperformance overall water splitting catalysis.

摘要：Sluggish water dissociation kinetics severely limits the rate of alkaline electrocatalytic hydrogen evolution reaction(HER).Therefore,finding highly active electrocatalysts and clarifying the mechanism of water dissociation are challenging but *** this study,we report an integrated nanoporous nickel(np-Ni)catalyst with high alkaline HER performance and the origin of the corresponding enhanced catalytic *** 1 mol L^(-1) KOH solution,this np-Ni electrode shows an HER overpotential of 20 mV at 10 mA cm^(-2),along with fast water dissociation *** excellent performance is not only attributed to the large surface area provided by the three-dimensional interconnected conductive network but also from the enhanced intrinsic activity induced by the unique surface *** studies reveal that the types of oxygen species that naturally form on the Ni surface play a key role in water ***,when the lattice oxygen almost disappears,the Ni surface terminates with_(ads)orbed oxygen(O_(ads)),exhibiting the fastest water dissociation *** functional theory calculation suggests that when O_(ads)acts as the surface termination of Ni metal,the orientation and configuration of polar water molecules are strongly affected by O_(ads).Finally,the H–OH bond of interfacial water molecules is effectively activated in a manner similar to hydrogen *** work not only identifies a high-performance and low-cost electrocatalyst but also provides new insights into the chemical processes underlying water dissociation,thus benefiting the rational design of electrocatalysts.

摘要：Based on experimental data,machine learning(ML) models for Young's modulus,hardness,and hot-working ability of Ti-based alloys were *** the models,the interdiffusion and mechanical property data were high-throughput re-evaluated from composition variations and nanoindentation data of diffusion ***,the Ti-(22±0.5)at.%Nb-(30±0.5)at.%Zr-(4±0.5)at.%Cr(TNZC) alloy with a single body-centered cubic(BCC) phase was screened in an interactive *** experimental results exhibited a relatively low Young's modulus of(58±4) GPa,high nanohardness of(3.4±0.2) GPa,high microhardness of HV(520±5),high compressive yield strength of(1220±18) MPa,large plastic strain greater than 30%,and superior dry-and wet-wear *** work demonstrates that ML combined with high-throughput analytic approaches can offer a powerful tool to accelerate the design of multicomponent Ti alloys with desired ***,it is indicated that TNZC alloy is an attractive candidate for biomedical applications.

摘要：长寿命溶解氧海水电池是深远海观测能源网络的重要组成单元,但海水贫氧复杂环境对设计高性能氧还原催化剂提出了重要挑战.本文以酞菁铁为模型催化剂,通过理论计算与实验验证,提出了活性位点电子轴向拉伸可大幅提升催化剂在极端贫氧环境中的氧还原活性和稳定性.该研究为构建高性能海水电池提供了材料学解决方案,同时为极端环境下催化剂的变革性设计提供了新的思路.

摘要：拓扑优化是结构优化设计领域中的重点和热点课题。结构渐进优化法(ESO)和遗传演化算法(GESO)是近年来提出的拓扑优化方法,可用于寻找结构最优的拓扑形状,指导结构概念设计。但这两种方法均存在诸多缺点,在工程应用中具有局限性。针对ESO和GESO方法的缺陷,发展了适用于拓扑优化的一种基于并行小生境比对法的改进遗传算法,并将改进遗传算法与ESO方法相结合,提出了灵敏度过滤技术和单元删除的修正判据,建立了引导式单元删除策略和孤立单元判断机制,形成了一种新的改进遗传演化算法(Improved Genetic Evolutionary Algorithm,IGEA),并以VC++作为编程平台,编写了集改进遗传算法、有限元、IGEA方法于一体的拓扑优化程序,有效实现了结构拓扑优化设计。算例表明,提出的IGEA方法优于ESO和GESO方法。

摘要：二维分子晶体是一类具有优异光电性能的新兴材料.然而,由于人们对决定二维结晶的因素知之甚少,二维分子晶体的生长极具挑战.我们研究了有机半导体的二维结晶和表面自由能之间的关系,提出了利用表面自由能各向异性因子来衡量二维结晶趋势的设想.以两个BTBT衍生物为例,我们发现具有大的g因子的分子有不受外界条件干扰的二维结晶趋势.这项工作为合理设计可二维结晶的有机半导体提供了指导.

摘要：With the ever-increasing demands of grid-scale energy storage,aqueous zinc-ion batteries(ZIBs)have garnered increasing attention around the ***,limited Zn^(2+)host materials have hindered the commercialization of ***,Mo-V oxides with different phase structures(orth-,tri-,and tetra-MoVO)were precisely constructed to develop phase-dependent Mo-V oxide cathodes for Zn^(2+)storage in *** open frameworks and varied tunnel structures formed a favorable alternative for achieving suitable Zn^(2+)diffusion *** optimized phase engineering,the high specific capacity of approximately 400 mA h g^(−1) and excellent cyclic stability of 1000 cycles were achieved with orth-MoVO as the *** large amount of six-and seven-member rings in the orth-MoVO phase,which allow for alternative Zn^(2+)insertion,play a vital role in hosting Zn^(2+)ions *** proposed phase engineering strategy provides a new approach toward cathode design in ZIBs.

摘要：电化学CO_(2)还原(CO_(2)RR)是一种很有前景的技术,可以将二氧化碳转化为多种增值化学品,从而达到减缓温室效应的目的.然而,实现目标产品的高催化活性、选择性和稳定性仍然是一个很大的挑战.本文通过还原Sn掺杂的Bi2S3制备了间隙掺杂的Snx-Bi (x为Sn与Bi的原子比,x=1/2,1/16,1/24或1/40)纳米线束(NBs).值得注意的是,Sn1/24-Bi NBs在1400 mV的宽电位窗口内表现出超高的甲酸盐选择性(从-0.5到-1.9 V vs.可逆氢电极(RHE),法拉第效率超过90%),在-1.9 V ***时,电流密度达到了-319 mA cm^(-2),可满足工业使用需求.此外,还实现了在~-200 mA cm^(-2)条件下超过84 h的超长稳定性.实验结果和密度泛函理论计算表明,间隙掺杂Sn优化了*OCHO中间体的吸附亲和力,降低了铋催化剂的电子转移能垒,从而获得了显著的CO_(2)RR性能.本研究为设计具有优异催化活性、选择性和耐久性的掺杂型电催化剂用于CO_(2)RR为甲酸盐提供了启示.

摘要：背景:鼻咽癌是我国南方重点防治的恶性肿瘤之一,探讨天然草本菊花活性成分在NPC化学预防的作用,对建立现代康复体系具有重要意义。目的:研究菊花活性成分倍半萜烯内酯(SLs)对人鼻咽癌细胞中线粒体功能和半胱天冬酶活化途径的影响。设计:完全随机对照分组设计。地点和对象:由中山大学公共卫生学院预防医学系完成,对象为低分化CNE2细胞株。干预:对parthenolide(PN)进行剂量-反应和时间效应作用观察,采用噻唑蓝(MTT)颜色反应检测细胞线粒体功能,底物荧光光谱法测定细胞内caspase-9和-3活性,蛋白免疫印迹法检测线粒体内细胞色素C释放和caspase-3酶原降解片段;并应用特异性抑制剂进行细胞内cas-pase途径阻断实验。主要观察指标:细胞线粒体功能、细胞内caspase-9和caspase-3活性、线粒体细胞色素C的释放和caspase-3酶原的降解。结果:PN(1～100μmol/L)作用12h和24h后,MTT颜色反应抑制率随剂量显著增高,呈明显剂量依赖性(Pearson'sr=0.7322,0.7703,P<0.05),IC50分别为252.94μmol/L和49.63μmol/L;但caspase-9和-3活性未见升高,未见细胞色素C释放和caspase-3酶原降解片段形成。PN与caspase抑制剂联合作用后,caspase-9和-3活性明显低于对照和单独PN作用(t=9.146,8.280,27.325,27.450,P<0.05)。

摘要：基于Lustre文件系统，对并行文件系统的性能评估和性能建模进行了研究．通过对性能因子的调研，进行了一系列性能评估实验，并提出性能相关性模~（PRModel）．在实验评估和PRModel分析中发现，在不同的性能因子之间存在着紧密的性能相关性，为了挖掘并利用这种相关性信息，提出了一种相对性能预测模（RPPModel）来预测不同性能因子条件下的性能．为了验证RPPModel的有效性，设计了大量实验用例．结果表明，预测结果的平均相对误差能够控制在170／o---28％的范围内，易于使用且具有较好的预测准确度．