摘要：Natural polyphenols are a large class of phytochemicals with neuroprotective effects. Four polyphenolic compounds: hesperidin, icariin, dihydromyricetin and baicalin were selected to evaluate their effects on Alzheimer's disease(AD). We analyzed by an inverse docking procedure(INVDOCK) the potential protein targets of these polyphenols within the KEGG AD pathway. Consequently, their therapeutic effects were evaluated and compared in a transgenic APP/PS1 mouse model of AD. These polyphenols were docked to several targets, including APP, BACE,PSEN, IDE, CASP, calpain and TNF-a, suggesting potential in vivo activities. Five month old transgenic mice were treated with these polyphenols. Icariin and hesperidin restored behavioral deficits and ameliorated Aβ deposits in both the cortex and hippocampus while baicalin and dihydromyricetin showed no substantial effects. Our findings suggest that hesperidin and icariin could be considered potential therapeutic candidates of human AD.

摘要：低矮建筑屋盖角区出现的高极值负压,是其围护结构抗风设计的重点。基于空气动力学原理,依据屋面角区绕流形态,基于TTU(Texas Tech University)标准建筑模型设计了一种屋面角区新型流线型附加构件,并通过改变附加构件高度、长度等参数,进行了10种工况的刚性模型测压风洞试验和大涡模拟(LES)对比研究,以探讨这类新型附加构件对屋面角区风荷载的影响和屋面抗风气动优化以及LES精度等问题。研究结果表明:屋面角区设置附加构件均可有效降低角区出现的极值负压,在所研究的10种工况中,屋面角区最不利平均负压最大可降低10%,最不利极值负压最大可降低25%;利用NSRFG(Narrowband Synthesis Random Flow Generation)方法生成入流湍流,采用LES得到的TTU模型各工况下的风荷载分布规律,虽然部分工况下屋面平均风压系数绝对值模拟结果偏大(平均误差为13.88%),而极值风压系数偏小(平均误差为9.72%),但整体上与风洞试验一致,表明利用NSRFG方法建立的低矮建筑绕流模型具有较好的精度;附加构件长度相对于高度而言对屋面角区风荷载的影响更大,等长附加构件高度增加1倍后,屋面角区极值风压系数降低6.15%,等高附件长度增加0.8倍后,屋面角区极值风压系数降低10.77%。

摘要：Electrocatalytic reduction reactions,powered by clean energy sources such as solar energy and wind,offer a sustainable method for converting inexpensive feedstocks(e.g.,CO_(2),N_(2)/NO_(x),organics,and O_(2))into high-value-added chemicals or *** design and modification of electrocatalysts have been widely implemented to improve their performance in these ***,bottle-necks are encountered,making it challenging to further improve performance through catalyst development ***,cations in the electrolyte have emerged as critical factors for tuning both the activity and product selectivity of reduction *** review summarizes recent advances in understanding the role of cation effects in electrocatalytic reduction ***,we introduce the mechanisms underlying cation *** then provide a comprehensive overview of their application in electroreduction *** techniques and theoretical calcula-tion methods for studying cation effects are also ***,we address remaining challeng-es and future perspectives in this *** hope that this review offers fundamental insights and design guidance for utilizing cation effects,thereby advancing their development.

摘要：以著名的LiB_(3)O_(5)为模板,通过增强其结构中B_(2)O_(5)的夹角使双折射更小,在封闭体系中通过高温溶液法获得了两种新的用于制造零级波片的双折射晶体Li_(2)MLaB_(18)O_(30)(M=Rb,Cs).有趣的是,相邻的B_(2)O_(5)接近垂直排列,使得它们表现出比商用石英晶体(Δn~0.0092在可见光区域)小得多的双折射率(分别为0.0032@532 nm和0.0027@532 nm).此外,Li_(2)MLaB_(18)O_(30)(M=Rb,Cs)晶体的紫外截止边均低于200 nm,表明它们可用作深紫外区域的零级波片材料.

摘要：直线增程系统是自由活塞发动机与直线电机直接耦合而成的新型高效、高功率密度能量转换系统,为了合理匹配系统电磁负荷,提升系统运行稳定性,该文研究了相应设计参数下系统稳定运行负荷极限,确定了不同电磁负荷下系统运行特性。利用MATLAB/Simulink建立了系统热动力学耦合仿真模型,确定系统负荷极限范围,得到了负荷极限范围内随着负荷的改变系统运行特性和性能特性的变化规律。结果表明:负荷对于系统运行特性有着决定性作用,当负荷从392增大到538N/(m·s^(-1)),系统运行频率从39.6减小到30.6 Hz,运行压缩比从15.0降低到6.0,指示热效率从41.4%降低到31.1%,系统输出功率从9.2 kW降低到5.3 kW,指示燃油消耗率由197.6 g/kWh增大到263.0 g/kWh。

摘要：降雨能否穿透厚包气带到达潜水面是地下水补给领域争议较大的问题。华北平原“23·7”极端降雨事件相当于华北平原的一次大型入渗试验,为分析潜水埋深如何控制地下水补给提供了契机。本研究以雄安新区白洋淀周边潜水浅埋区4口自动监测井和容城县境内潜水深埋区6口自动监测井为例,分析不同埋深地下水对2023年3日内累积降雨量为289.2 mm的极端降雨事件的响应规律。在潜水浅埋区,暴雨开始后约16 h垂向入渗至潜水面,潜水抬升幅度达1.36~1.79 m;在潜水深埋区,暴雨后河水水位迅速抬升并引发渗漏形成水丘,在潜水回水作用下离南拒马河距离小于6 km的潜水位以较快速度抬升1.38~3.67 m。本研究表明,降雨沿着包气带的垂向入渗是潜水浅埋区地下水的补给来源,暴雨后河水入渗引发的潜水回水是河道附近潜水深埋区地下水补给的主要来源。本文加深了对不同埋深潜水补给机理的认识,对今后分析华北平原乃至其他地下水超采区的水位回升控制机理、生态补水效果具有重要指导意义。

摘要：As an important energy carrier in terms of carbon neutrality,green hydrogen produced by water electrolysis using renewable electricity has attracted worldwide *** polymer electrolyte water electrolyzer(PEWE)has the potential to be a mainstay in the green hydrogen market in the future because of its superior ***,the development of PEWE is constrained by the slow progress of the membrane electrode assembly(MEA),which is an essential component of PEWE and largely determines the cost and performance of the ***,the MEA must be optimized from the aspects of reducing cost and improving performance to promote the development of *** this review,we first discuss the recent progress of the materials and design strategies of MEA,including the cost,activity,and stability of catalysts,distribution and thickness of ionomers,and ion transport efficiency of ion exchange membranes(IEMs).Then,the effects of all components and interlayer interfaces on the ions,electrons,and mass transfer in MEA and,consequently,the performance of PEWE are ***,we propose perspectives on developing MEA by optimizing the catalyst activity and stability of IEM,interface contact between adjacent components,and evaluation methods of performance.

摘要：我国股票市场与艺术品市场作为两个重要的投资领域,存在着显著的相关性。一方面,它们都与宏观经济联系紧密;另一方面,两个市场间存在着竞争效应和财富溢出效应。通过运用分别反映两个市场总体态势的指数数据所构建的向量自回归模型和向量误差修正模型以及在此基础上进行的相关检验可以得出如下结论:投资者基于艺术品市场的变化可以实现对股票市场的预测,从长期来看,艺术品市场与股票市场呈正相关。

摘要：虽然纤维增强塑料复合材料在很多领域,如,飞行器工业,汽车工业,造船工业和房屋建造等方面得到了广泛的应用,但是由于其破坏行为的复杂性,使其应用和设计受到了限制。含孔复合材料的性能已经成为研究的一个热点。本研究通过引进针刺工艺以提高含孔玻璃纤维增强塑料复合材料的性能。该工艺不仅降低了层间纤维的距离同时也引入了垂直于板材的刺入纤维。本文使用直径为10mm的钻头来制备复合材料上的圆孔。文中通过对比普通玻璃纤维毡复合材料和经过针刺后玻璃纤维毡复合材料的性能,分析了破坏行为和拉伸性能的差异性,并通过利用MSC-Marc的有限元分析对比了两种材料对于圆孔的敏感性。研究表明,经过针刺后制成的玻璃纤维毡复合材料对于圆孔的敏感性相对较低。

摘要：伴随着经济发展和物质财富的积聚,艺术品日益展现出其作为资产和投资品的特征,艺术金融逐渐成为金融学的一个新兴领域。从国外艺术金融研究领域近50年的经典和前沿文献来看,艺术品展现出的特殊性和金融属性推动学术界不断探索艺术品价格形成的经济学逻辑、艺术品估价、风险收益特征以及其与传统金融资产的关系等。本文从微观角度阐述了艺术品价值决定的理论基础,并力图指出现有研究的不足,提出未来我国艺术金融理论研究的建议与展望。