摘要：Electrorheological (ER) fluids, or suspensions, as one kind of smart materials, have very important and potential applications in electromechanical control due to their attractive features of rapid (with ms order), reversible, and controllable changes in rheological properties upon the application of an external electric field with kV/mm order[1～3]. Once ER fluids have met the engineering targets, they will bring revolution in several areas of industry and technology such as mechanics, trans portation, hydraulics and so on[4].

摘要：Electrocatalytic urea synthesis provides a favorable strategy for conventional energy-consuming urea synthesis,but achieving large-scale catalyst synthesis with high catalytic efficiency remains ***,we developed a simple method for the preparation of a series of FeNi-alloy-based catalysts,named FeNi@nC-T(n represents the content of nanoporous carbon as 1,3,5,7 or 9 g and T=900,950,1000 or 1100°C),for highly performed urea synthesis via NO_(3)−and CO_(2)*** FeNi@7C-1000 achieved a high urea yield of 1041.33 mmol h^(−1)gFeNi^(−1)with a Faradaic efficiency of 15.56%at–1.2 V ***,the scale-up synthesized FeNi@7C-950-S(over 140 g per batch)was achieved with its high catalytic performance and high stability *** investigation illuminated that the Ni and Fe sites catalyze and stabilize the key*CO and*N intermediates and minimize the C–N coupling reaction barriers for highly efficient urea synthesis.

摘要：直线电机的推力波动较大,限制其在超精密领域的应用。推力中的谐波是无铁心永磁同步直线电机推力波动的主要原因之一,消除推力中的部分谐波可以有效降低推力波动。该文建立了无铁心永磁体同步直线电机推力谐波的解析模型,揭示了结构参数与推力波动间的关系,并提出了低推力波动直线电机的设计准则。将设计准则应用于一类直线电机的优化设计中,提出了消除推力中特定阶次谐波的结构参数设计方法。设计结果与有限元仿真结果和实验结果进行比对,验证了解析模型的准确性和设计方法的有效性。

摘要：Organic photovoltaic(OPV)is one of the most promising technologies for powering indoor electronic *** high-performance indoor organic photovoltaics(IOPV)require medium bandgap materials to absorb visible light efficiently and reduce energy ***,state-of-theart A-DA’D-A type small molecule acceptors(SMAs)have absorptions in the near-infrared region which mismatches with the room *** this work,two medium bandgap ADA’D-A type SMAs BTOL-Br and DFOL-Br were synthesized by a molecular synergetic modification strategy for the applications in *** results show that DFOL-Br with replacing the A’unit of benzothiadiazole in BTOL-Br by difluorine substituted benzene ring,exhibits blue-shifted absorption spectra and an up-shifted lowest unoccupied molecular orbital(LUMO)energy level than those of *** blending the SMAs with a polymer donor PBQx-TCl,the DFOL-Br-based film shows more ordered molecular packing and suitable phase *** a result,the DFOLBr-based device achieves a higher indoor efficiency of 26.8% under a 2600 K light-emitting diode lamp at 2000 lux than that of the BTOL-Br-based one(23.2%).This work indicates that the synergetic modification is an effective strategy for preparing medium bandgap A-DA’D-A type SMAs,which may become a useful SMA design guideline for developing highperformance IOPVs.

摘要：射频调制的脉冲激光是激光雷达探测领域内的一项重要研究内容.根据声光斩波器的强度和频率调制特性,设计了基于频移反馈腔的全光纤射频调制脉冲激光.理论上,建立了基于频移反馈腔的激光外差相干理论模型,并进行了数值仿真.根据理论模型,实验上严格控制频移反馈腔的长度和声光斩波器触发信号的周期,在100 MHz的射频信号驱动下,产生了脉冲宽度110 ns、重复频率约20 kHz的具有最高700 MHz射频调制的脉冲激光(脉内调制激光);同时微调斩波周期可以实现脉冲前沿或后沿的多样性射频调制.通过改变反馈腔内光纤放大器的输出功率实现了射频调制深度的连续可调,最高达到了0.67.

摘要：金融借贷不仅是一种资源的跨期配置,对居民更是产生了未来虚拟财富预期。基于此,笔者阐述了金融借贷虚拟财富产生过程及其影响消费机理并提出研究假设,采用中国家庭追踪调查(CFPS)数据,在对金融借贷的虚拟财富水平进行量化的基础上,运用有序Probit模型实证检验二元金融对城乡家庭消费的虚拟财富效应。研究发现:二元金融对消费都产生积极的虚拟财富效应,并且形成联动后的虚拟财富效应都得到充分释放;与收入等真实财富相比,虚拟财富更有利于增加居民消费支出。论文拓展了虚拟财富理论的研究范畴,为研究信贷与消费增添了新的内容。

摘要：为解决印刷图像分色中的颜色转换和黑版生成问题,本研究提出了最大化CMYK颜色空间输出色域的K值标定算法。该方法首先将印刷色域空间视为CMY色立体,并划分成6个子色域空间;其次设计色标和算法,计算每个子色域的中心黑版查找表和边界黑版查找表;然后通过判断输入颜色所处的子色域空间找到其对应的查找表,再根据查找表上所对应的点,进行插值计算,确定最终的CMYK分色值;最后通过领域搜索方法对结果进行进一步优化。色差评价实验显示:K值标定算法针对标准测试色靶复制得到的均值色差低于1个标准色差单位,最大色差与商业色彩管理软件i1 Profiler接近。色域复制评价实验显示:相对于灰平衡算法,分色计算后数据点的色域分布情况以及色域空间大小与源色域空间更为接近。图像复制评价实验显示:本研究算法对图像的暗部细节能够进行较好的还原。通过印刷测试,新算法可以满足印刷工业图像复制要求。

摘要：The high phase content of inorganic dielectric fillings will give a strong electric driving force and hard matrix. That is a contradiction in enhancing the electrodeformation of dielectric elastomers(DEs). Therefore, in this paper, by focusing on how to approach a balance between these and finding an effective way to tune the electric response of the DEs, the theoretical calculation and experimental investigation based on calcium copper titanate(CCTO)/poly(dimethyl siloxane)(PDMS) were carried out. It is found that CCTO with a smaller particle size shows a larger dielectric parameter. With smaller CCTO particle as the fillings, the fabricated elastomer composite would approach to a low modulus by a proper CCTO phase morphology in the matrix.

摘要：结构应力分布状态的确定是结构进行疲劳强度评估和可靠性设计的重要依据。通过在全程实测提速客车转向架构架关键部位应力 -时间历程的基础上 ,对其进行雨流记数后 ,利用可靠性理论 ,通过合理的分组得到测点应力的直方图和失效率图 ,以此为依据详细分析了提速客车转向架构架关键部位动应力分布特征 ,得出了我国提速机车车辆转向架构架在既有线路上运行时的应力特点是小载荷占绝对主导地位 ,并服从截尾正态分布。然后利用非线性单纯形最优化方法求得应力分布的分布参数 ,最后得到提速客车转向架应力分布规律。

摘要：针对轴流式涡轮部件结构复杂、精度要求高以及研制周期较长等特点,开展了基于三维光学扫描及逆向工程技术的小尺寸高性能轴流式涡轮部件逆向设计。通过非接触式三维结构光学扫描仪获取了涡轮整体叶盘及导向器实物的点云数据;在点云数据预处理及自动对齐的基础上,利用复杂型面三维重构技术,实现了部件的三维数字化模型重建;基于有限元分析开展了部件的气动性能及结构强度计算,验证了逆向设计轴流式涡轮部件的可行性;并通过进一步梳理总结,建立了轴流式涡轮部件逆向设计流程。结果表明,建立的轴流式涡轮部件逆向设计方法及流程可使得设计部件有效满足实际使用要求,显著缩短设计周期,能够为同类部件的设计提供指导和借鉴。