摘要：Birefringence arises when the propagation speed and refractive index of light in an optically anisotropic crystal changes in response to the direction of ***,birefringence belongs to linear optical anisotropy and is a key parameter for linear optoelectronic functional crystals,such as birefringent crystals,which are widely used to modulate the polarization of light in optoelectronic areas[1].In terms of practical applications,there is still an urgent need for wide-bandgap birefringent crystals as they allow for the modulation of light polarization in short-wavelength UV waves and even in the deep-UV spectral region.

摘要：Two-dimensional(2D) ternary materials have sprung up in a broad variety of optoelectronic applications due to their robust degree of freedom to design the physical properties of the materials through adjusting the stoichiometric ratio. However, the controlled growth of high-quality 2D ternary materials with good chemical stoichiometry remains challenging, which severely impedes their further development and future device applications. Herein, we synthesize ternary Bi_(2)Te_(2)Se(BTS) flakes with a thickness down to 4 nm and a lateral dimension about 60 μm by an atmospheric-pressure solid source thermal evaporation method on a mica substrate. The phonon vibration and electrical transportation of 2D BTS are respectively investigated by temperature-dependent Raman spectrum and conductivity measurements. Furthermore, the photodetector based on 2D BTS exhibits excellent performance with a high light on/off ratio of 1300(365 nm), a wide spectral response range from 365 to 980 nm, and an ultra-fast response speed up to 2 μs. In addition, its electrical and photoelectric properties can be modulated by the gate voltage, offering an improved infrared responsivity to 2.74 A W^(-1) and an on/off ratio of 2266 under 980 nm. This work introduces an effective approach to obtain 2D BTS flakes and demonstrates their excellent prospects in optoelectronics.

摘要：Two-dimensional(2D)hybrid perovskites with the Ruddlesden-Popper lattice(A')_(2)(A)_(n-1)M_(n)X_(3n+1)are emerging as the promising optoelectronic candidates,both the inorganic and organic ingredients of which can be tailored to modulate the physical ***,there is a scarcity of 2D multilayered motifs with the A-site large-size cations occupying perovskite ***,by rational mixedcation alloying,we present a new 2D hybrid perovskite,(4-TFBMA)_(2)(DMA)Pb_(2)I_(7)(1),in which the secondary cation of CH_(3)NH_(2)CH_(3)^(+)(DMA)is located inside the perovskite cage while the aromatic 4-(trifluoromethyl)benzylammonium(4-TFBMA)cation acts as a spacer *** from the quantum structure of alternating organic spacers and inorganic networks,crystal-array detectors of 1 show fascinating in-plane photodetection responses of large detectivity(~2.95×10^(12)Jones)and responsivity(~1.97AW^(-1)),comparable to those of some inorganic 2D *** addition,a fast response rate(~264μs)and a low dark current are also realized,related to the high crystalline quality and suppression of the hopping barrier due to the insulating organic spacing *** result sheds light on the further exploration of new 2D hybrid perovskites toward high-performance photodetector applications.

摘要：综合了空气中、直接埋地两种敷设下电力电缆短期允许负载电流的计算方法,研究了其中土壤划分区域个数的选择、短时负载前电缆非满载运行下线芯温度的确定等问题并参考载流量计算中相关参数的确定方式,给出了电缆在直埋更换回填土以及水泥槽中管道敷设情况下的短期负载电流计算公式,并以简单计算验证其正确性。相关设计思想可供其它敷设方式的电缆短期负载电流计算参考。

摘要：按照特殊设计的取样原则,收集了50个运行年限为1～14 a的XLPE绝缘电力电缆样品,通过结构参数和水树枝试验,研究分析XLPE介质中杂质、微孔和不均匀性(偏心度)等结构参数及电缆敷设方式、运行环境条件与XLPE介质水树枝早期劣化现象.研究结果表明,杂质、水分和电场是引发XLPE绝缘电力电缆介质树枝状早期老化的直接因素,并最终导致XLPE绝缘电力电缆发生运行故障.

摘要：以拓展刺激-机体-反应理论为分析框架,利用腾讯问卷样本服务采集854份样本数据,构建结构方程模型考察家庭亲环境导向对居民以竹代塑亲环境行为的影响,同时考察自然共情和低努力亲环境行为的中介作用及自然联结的调节作用。实证结果表明:1)家庭亲环境导向、自然共情和低努力亲环境行为均显著正向影响居民以竹代塑亲环境行为。2)家庭亲环境导向对以竹代塑亲环境行为产生的直接效应小于间接效应。间接效应包括自然共情与低努力亲环境行为各自产生的显著中介效应,以及二者共同产生的显著链式中介效应;其中,低努力亲环境行为产生的中介效应最大。3)低努力亲环境行为与以竹代塑亲环境行为间存在显著的正向溢出效应。4)自然联结显著负向调节家庭亲环境导向对低努力亲环境行为和以竹代塑亲环境行为的影响。据此提出,应强化家庭亲环境氛围,培养居民对自然的情感联系,推广低努力亲环境行为,将宣传教育侧重点放在亲环境行为的环境益处而非经济效益。

摘要：为实现烟叶烘烤节能降耗的目的,对目前应用的气流上升式连体密集烤房设计余热共享设备进行研究,使之相互间实现余热共享。设计的气流上升式连体密集烤房余热共享设备,具有结构简单、容易操作的特点,能够实现烤房间的余热共享,利用定色、干筋期排出的余热能完全满足烟叶变黄所需的热量,节能效果明显,公斤干烟耗煤量和烘烤成本较对照明显降低,且利用余热烘烤的烟叶质量能得到保证。

摘要：利用有机含氮杂环小分子吡咯烷与氯化锌、盐酸反应,制备得到1例新颖的金属有机相变化合物——四氯合锌酸二吡咯烷.通过差热扫描量热(DSC)测试,在升温(339.5 K)和降温(320.5 K)过程中出现可逆的热力学相变峰和较大的的热滞(19 K),表明该化合物发生了可逆的一级相变.对其变温介电常数进行分析,室温下低介电态到高温下高介电态的转变进一步证实了化合物发生结构相变.通过变温X射线单晶衍射,研究了晶体在150和353 K晶体结构,揭示了其相变机理,表明锌离子的相对位移是该化合物相变的主要原因.

摘要：山区河道型库岸滑坡及其产生的涌浪给库区航运、旅游、生产生活以及人员财产造成巨大威胁和损害。以三峡库区万州段为研究范围,基于Arc GIS Engine和Skyline等专业软件,在山区河道型水库滑坡涌浪安全评估系统整体设计的基础上,详细分析了初始涌浪高度、涌浪传播与衰减系数、固流能量交换系数、涌浪爬高、横摇角度以及涌浪安全评估等核心功能的实现流程、实现算法及具体操作。该系统不但能快速计算出滑坡产生后某特定网格单元的涌浪特征值,而且能通过系统的批量计算模拟得到研究区河段范围内所有网格单元的涌浪特征值分布情况。研究成果可为滑坡涌浪灾害空间预警及航道安全评价与管理等提供可视化分析平台。

摘要：为了在不降低安全性能的基础上完成轻量化指标,采用有限元仿真技术对某车型桥壳结构性能进行分析,包括模态分析、强度分析,并根据桥壳结构应力随材料厚度、强度的变化规律提出该桥壳轻量化选材方案,即选材由原来的5.0 mm-SAPH440优化为4.0 mm-P590QK,此时桥壳的疲劳强度后备系数指标及刚度指标均满足标准要求,静强度后备系数略低于标准要求,但由于材料实物强度均高于理论计算时采用的最低值,故其静强度后备系数能够满足实际要求.现场冲压试验及台架性能检测结果表明,4.0 mm-P590QK桥壳成形性及结构疲劳、刚度、强度等性能均达到了设计要求.本方案使桥壳零件减重20%,达到了轻量化指标.