万安水利枢纽底孔坝段中隔墙流激振动响应分析

 研究了万安水利枢纽底孔坝段中隔墙在水流脉动壁压作用下的结构随机振动问题，进行了一种泄流工况下的隔墙结构流激振动响应统计量的理论计算，模拟计算了隔墙－水流－基础耦合系统固有频率对流激振动响应的影响，并对水流脉动壁压随机荷载作用下的结构动力可靠度进行了理论分析。     

共面波导有限金属厚度效应的研究

用保角变换法对共面波导金属厚度效应进行了理论分析，编制了相应的计算机程序，给出了数值解，并对此进行了多元曲线拟合，导出了考虑金属厚度后的形状比k、有效介电常数、特征阻抗、损耗的闭定表达式。用此修正表达式求得特征阻抗及损耗的数值解，并与K．C．格普塔的修正值及实验测量值进行了详细比较，结果表明此修正公式与实验值相符较好。     

Structure characterization within the vicinity of the fine granular area by synchrotron radiation nano‐CT

The three‐dimensional (3D) microstructures within the vicinity of the fine granular area (FGA) were investigated with synchrotron radiation nano‐computed tomography (CT). In this investigation, the very high cycle fatigue test of a high‐strength steel was carried out with an ultrasonic fatigue testing machine. Then, focused ion beam cutting was used to cut a part near the surface of the FGA. Finally, the 3D structure of the sample was obtained with the nano‐CT imaging. The results indicated that the base material was composed of various subgrains that are tens to hundreds nanometres in size. Through analysis of the slices, small granular areas consist of several subgrains. The statistical analysis of the subgrain size indicated that the subgrain size near the surface of the FGA is similar to that far from the surface of the FGA and near the fracture surface except the FGA. It indicated that the refinement has not been found by nano‐CT.     

碳/碳复合材料的热物理性能和抗热震性的研究

本文用激光脉冲法、石英示差法和激光扫描法研究测量了室温至2000℃碳/碳复合材料的热物理性能,包括导热系数和热膨胀系数。通过抗热震系数研究分析了三向细编碳/碳复合材料和碳布两向增强碳/碳复合材料的抗热震性。研究了温度、密度和取向等对碳/碳复合材料的热物理性能和抗热震性的影响。      

Large-scale uniform α-Co(OH)₂ long nanowire arrays grown on graphite as pseudocapacitor electrodes

Large-scale uniform α-Co(OH)? nanowire arrays (NWAs) with an average length of ～20 μm grown on pyrolytic graphite (PG) were successfully synthesized by a hydrothermal method at 120 °C. Ultrasonication test was carried out toward the as-made nanoarray products and the result demonstrated their robust adhesion to graphitic substrate. After 300 s of sonication testing, α-Co(OH)? NWAs could still possess both integrated one-dimensional (1D) nanoarray architecture and good electronic connections with current collector. When investigated as electrochemical pseudocapacitor electrodes, α-Co(OH)? NWAs exhibited good energy-storage performance in terms of high specific capacitance of 642.5 F/g, good rate capability, and excellent capacity retention. Our work not only presents a cost-effective and scale-up synthetic method for α-Co(OH)? NWAs but also holds promise in general synthesis of long arrays of other metal hydroxides/oxide (TiO?, Fe?O?, SnO?, etc.) nanostructures on PG substrate by using α-Co(OH)? NWAs as sacrificial templates.     

Efficient visible light driven photocatalytic removal of NO with aerosol flow synthesized B, N-codoped TiO2 hollow spheres

In this study, we demonstrate that aerosol assisted flow synthesized B, N-codoped TiO(2) photocatalyst possesses superior photocatalytic activity to pure and single element doped counterparts on the degradation of NO in a flow system under both simulated solar light and visible light irradiation. Characterization results revealed that B, N-codoped TiO(2) photocatalyst was composed of hollow microspheres. Boron and nitrogen were in the form of Ti-O-B and N-Ti-O structures, respectively. The introduction of B and N into the TiO(2) lattice could effectively tune the band gap of TiO(2) and extend its optical response to the visible-light region. The synergistic effect of B and N codoping on visible light driven photocatalytic activity enhancement of TiO(2) was discussed on the basis of experimental results.     

涂层转移法精密铸造技术在子午线轮胎模具制造中的应用

子午线轮胎模具计算机辅助快速制造系统是由ＣＡＤ技术、快速成型技术、涂层转移法精密铸造技术、材料技术等多项高新技术组合而成的一项独特的先进制造技术。该系统充分利用液态材料成型任意性和高再现性的特点，具有适应性强、重复性好、加工周期短、制造成本低的特点。     

The link between ethnic diversity and scientific impact: the mediating effect of novelty and audience diversity

Scientometrics - Understanding the nature and value of scientific collaboration is essential for sound management and proactive research policies. One component of collaboration is the composition...     

Carbon–Oxygen‐Bridged Ladder‐Type Building Blocks for Highly Efficient Nonfullerene Acceptors

Recently, acceptor–donor–acceptor (A–D–A) small molecules have emerged as promising nonfullerene acceptors (NFAs) for organic solar cells and have attracted great attention. The carbon‐bridged (C‐bridged) ladder‐type D unit plays a crucial role in developing high‐performance A–D–A NFAs. However, the medium electron‐donating capability of C‐bridged units is unfavorable for making NFAs with strong light‐harvesting capability. In this regard, carbon–oxygen‐bridged (CO‐bridged) ladder‐type units present advantages in developing strong light‐absorbing NFAs. Here, recent progress in the newly emerging CO‐bridged NFAs is highlighted. The synthetic methods for the polycyclic CO‐bridged building blocks are introduced. The photovoltaic performance for CO‐bridged NFAs is summarized and discussed. Perspectives on developing high‐performance CO‐bridged‐NFA‐based solar cells are made.     

生物源方铁锰矿吸附Cu（II）和Zn（II）的特性

利用从土壤中分离出来的Mn（II）氧化细菌Providencia sp. LLDRA6,制备和纯化生物锰氧化物。通过扫描电镜-能谱（SEM-EDS）、X射线衍射（XRD）、高分辨率透射电镜-选区电子衍射（HRTEM-SAED）、X射线光电子能谱（XPS）和比表面积测定（SSA）等手段,对生物锰氧化物进行了表征分析。研究结果表明：得到的生物锰氧化物是弱结晶的方铁锰矿（Mn2O3）,比表面积为5.740 m2/g;生物源Mn2O3对Cu（II）和Zn（II）具有较强的吸附能力,吸附最适pH均为6,吸附容量分别为89.889 mg/g和70.595 mg/g;生物源Mn2O3吸附Cu（II）和Zn（II）的动力行为均符合伪二级动力学模型,表明生物源Mn2O3吸附Cu（II）和Zn（II）的速率受化学吸附的控制;生物源Mn2O3对Cu（II）和Zn（II）的吸附均符合Langmuir等温吸附模型,表明吸附类型属于单分子层吸附。