摘要：Aqueous zinc ion hybrid capacitors(ZIHCs)are considered one of the most promising electrochemical energy storage systems due to their high safety,environmental friendliness,low cost,and high power ***,the low energy density and the lack of sustainable design strategies for the cathodes hinder the practical application of ***,we design the N and O co-doped porous carbon cathode by annealing metal-organic framework(ZIF-8).ZIF-8 retains the original dodecahedral structure with a high specific surface(2814.67 m^(2)/g)and I_(G)/I_(D) ratio of 1.0 during carbonization and achieves self-doping of N and O *** defect sites are introduced into the porous carbon to provide additional active sites for ion adsorption after the activation of carbonized ZIF-8 by KOH *** ZIHCs assembled with modified ZIF-8 as the cathode and commercial zinc foil as the anode show an energy density of 125 W∙h/kg and a power density of 79 W/*** addition,this ZIHCs device achieves capacity retention of 77.8%after 9000 electrochemical cycles,which is attributed to the diverse pore structure and plentiful defect sites of ZIF-8-800(KOH).The proposed strategy may be useful in developing high-performance metal-ion hybrid capacitors for large-scale energy storage.

摘要：In order to overcome the limitations of traditional microperforated plate with narrow sound absorption bandwidth and a single structure,two multi-cavity composite sound-absorbing materials were designed based on the shape of monoclinic crystals:uniaxial oblique structure(UOS)and biaxial oblique structure(BOS).Through finite element simulation and experimental research,the theoretical models of UOS and BOS were verified,and their sound absorption mechanisms were *** the same time,the influence of multi-cavity composites on sound absorption performance was analyzed based on the theoretical model,and the influence of structural parameters on sound absorption performance was *** research results show that,in the range of 100-2000 Hz,UOS has three sound absorption peaks and BOS has five sound absorption *** frequency range of the half-absorption bandwidth(α>0.5)of UOS and BOS increases by 242% and 229%,*** with traditional microperforated sound-absorbing structures,the series and parallel hybrid methods significantly increase the sound-absorbing bandwidth of the sound-absorbing *** research has guiding significance for noise control and has broad application prospects in the fields of transportation,construction,and mechanical design.

摘要：Bacterial infection is a major problem following bone implant ***,poly-l-lactic acid/carbon nanotube/hydroxyapatite(PLLA/CNT/HAP)bone scaffolds possess enhanced mechanical properties and show good ***,wesynthesizedsilver(Ag)-dopedCNT/HAP(CNT/Ag-HAP)nanohybrids via the partial replacing of calcium ions(Ca2+)in the HAP lattice with silver ions(Ag+)using an ion doping technique under hydrothermal ***fically,the doping process was induced using the special lattice structure of HAP and the abundant surface oxygenic functional groups of CNT,and involved the partial replacement of Ca2+in the HAP lattice by doped Ag+as well as the in situ synthesis of Ag-HAP nanoparticles on CNT in a hydrothermal *** result-ing CNT/Ag-HAP nanohybrids were then introduced into a PLLA matrix via laser-based powder bed fusion(PBF-LB)to fabricate PLLA/CNT/Ag-HAP scaffolds that showed sustained antibacterial *** then found that Ag+,which pos-sesses broad-spectrum antibacterial activity,endowed PLLA/CNT/Ag-HAP scaffolds with this activity,with an antibacterial effectiveness of 92.65%.This antibacterial effect is due to the powerful effect of Ag+against bacterial structure and genetic material,as well as the physical destruction of bacterial structures due to the sharp edge structure of *** addition,the scaffold possessed enhanced mechanical properties,showing tensile and compressive strengths of 8.49 MPa and 19.72 MPa,***,the scaffold also exhibited good bioactivity and cytocompatibility,including the ability to form apatite layers and to promote the adhesion and proliferation of human osteoblast-like cells(MG63 cells).

摘要：缺陷位点的引入可以通过增加对反应中间体的亲和力来提高催化剂的催化能力.纳米材料中存在多种缺陷类型,如阳离子缺陷和阴离子缺陷.不同的缺陷位点对电催化性能的贡献不同.因此,构筑缺陷必须精准、明确,以便于确定最优的缺陷类型,促进电化学反应.在这项工作中,我们以钴空位为例,分别成功合成了二价钴空位(Co3O 4-VCo(II))和三价钴空位(Co_(3)O_(4)-VCo(III))的Co_(3)O_(4).电化学结果表明,钴空位的引入可以显著提高Co_(3)O_(4)的电催化性能.Co_(3)O_(4)-VCo(II)表现出最突出的析氧反应(OER)性能,反应动力学速率最快.X射线光电子能谱分析表明,在OER过程中,VCo(II)的存在可以使CoOOH活性位点快速形成.密度泛函理论计算表明,钴空位的引入使Co_(3)O_(4)拥有类似金属的导电性.VCo(II)的存在使得O p带中心靠近费米能级,自由能势垒降低,电催化剂表面氧交换动力学速率加快,对反应中间体的吸附能最佳,从而表现出优异的电化学性能.本研究为设计高效的富缺陷电催化剂提供了重要指导.

摘要：二维过渡金属硫族化合物(TMDCs)材料被认为是拓展摩尔定律的极具前景的候选材料.然而,该材料的低光致发光效率严重限制了其实际应用,其本质源于材料制备中不可避免引入的缺陷.在本文中,我们报道了一种Sr掺杂单层MoS_(2)的有效缺陷工程策略,该策略在实验上通过简便的化学气相沉积(CVD)一步法成功实现.所制备的具有亚毫米(~324μm)级的大尺寸样品的光致发光可实现高达两个数量级的增强,并伴随着载流子寿命的显著增强.这一现象主要归因于Sr掺杂后MoS_(2)体系中其三激子向激子转换.与此同时,掺杂样品的辐射质量和稳定性也显著提升.第一性原理计算进一步阐明了其调控机制,即在MoS_(2)中引入适当互补缺陷能级与其自身的缺陷能级协同,从而可调节其载流子组分,以实现光致发光的显著增强.此外,我们的缺陷工程策略也适用于其他掺杂剂,如钙掺杂剂.我们的工作报告了一种可以显著提升单层MoS_(2)的荧光性能的有效缺陷工程策略,这为设计和调控二维TMDCs的光电特性提供一种极具前途的方法.

摘要：设S=(P,B)是一个非平凡的3-(v,7,λ)设计且满足λ≥2.本文证明:如果G是S上的一个区传递自同构群,则G是仿射型或者几乎单型的点本原群.此外,我们还考虑G的基柱为交错群A_n的一种有限几乎单群的情形.

摘要：Transverse pressure gradient(TPG)is one of the key factors influencing the boundary layer airflow diversion in a bump *** paper proposes a novel TPG-based hypersonic bump inlet design *** method consists of two ***,a parametric optimization approach is employed to design a series of 2D inlets with various compression ***,according to the prescribed TPG,the optimized inlets are placed in different osculating planes to generate a 3D bump *** method provides a means to directly control the aerodynamic parameters of the bump rather than the geometric *** performing this method to a hypersonic chin inlet,a long and wide bump surface is formed in the compression wall,which leads to good integration of the bump/*** show that a part of the near-wall boundary layer flow is diverted by the bump,resulting in a slight decrease in the mass flow but a significant improvement in the total pressure *** addition,the starting ability is significantly improved by adding the bump *** reveals that the bump has a 3D rebuilding effect on the large-scale separation bubble of the unstarted ***,a mass flow correction is performed on the designed bump inlet to increase the mass flow to full airflow *** results show that the mass flow rate of the corrected bump inlet reaches up to 0.9993,demonstrating that the correction method is effective.

摘要：风屏障由于能提高侧风下列车的行车安全性,近年来引起了学者的广泛关注。然而,在过去的几十年中,风屏障结构参数(如风屏障高度和透风率等)对列车迎风面和背风面的平均压力系数差的影响研究尚不充分。为综合考虑风屏障高度、透风率以及风屏障与列车间距对列车平均压力系数差的影响,本文基于正交设计方法,对25个不同结构参数工况进行了详细数值模拟研究,并采用同步风洞试验验证了结果的正确性。研究结果表明:随着透风率(R)的增加,列车平均压力系数差先减小后增大;随着高度(H)的增加,列车平均压力系数差先增加后减少;而随着风屏障与列车间距(D)的增大,列车平均压力系数差则呈单调减小趋势。此外,根据极差与方差分析理论发现,三个因素的相对重要性为:透风率>高度>风屏障与列车间距。最后,确定了建议风屏障透风率和高度,分别为20%和110 mm。而当透风率为40%,高度为85 mm时,列车处于相对不安全的状态。研究成果可为风屏障的结构设计提供参考。

摘要：开发具有宽温度范围、无枝晶生长和耐腐蚀的电解质对于水系金属锌电池的实际应用至关重要.本研究开发了一种γ-戊内酯共溶剂,以扩大水系电解质的工作温度范围并稳定锌金属阳极的界面.这种弱溶剂作为强氢键配体和“稀释剂”,高效地打破了自由水分子之间的氢键,从而提高了电解液的温度耐受性和化学稳定性.同时,γ-戊内酯也可以吸附在阳极表面从而促进锌的成核和调节锌的生长织构,实现无枝晶的锌沉积.这种优化后的电解质可以使对称电池的寿命达到2160 h,并可以在-50~80℃的宽温度范围内稳定运行.相应的ZnⅡ活性炭电容器和ZnⅡ聚苯胺电池在8100和1600次循环后,容量保持率分别为92.5%和85%.这种弱溶剂调控氢键和锌离子的溶剂鞘的机制为先进的水系电解质的设计提供了新的见解.

摘要：Although human-induced pluripotent stem cell-derived cardiomyocytes(hi PSC-CMs) have been used for disease modeling and drug discovery, clinically relevant three-dimensional(3D) functional myocardial microtissues are lacking. Here, we developed a novel ring-shaped cardiac microtissue comprised of chamber-specific tissues to achieve a geometrically non-orientable ventricular myocardial band, similar to a M?bius loop. The ring-shaped cardiac tissue was constructed of hi PSC-CMs and human cardiac fibroblasts(h CFs) through a facile cellular self-assembly approach. It exhibited basic anatomical structure,positive cardiac troponin T(c Tn T) immunostaining, regular calcium transients, and cardiac-like mechanical strength. The cardiac rings can be self-assembled and scaled up into various sizes with outstanding stability, suggesting their potential for precise therapy, pathophysiological investigation, and large-scale drug screening.