摘要：Tunneling heterostructures are emerging as a versatile architecture for photodetection due to their advanced optical sensitivity,tailorable detection band,and wellbalanced photoelectric ***,the existing tunneling heterostructures are mainly operated in the visible wavelengths and have been rarely investigated for the nearinfrared ***,we report the design and realization of a novel broken-gap tunneling heterostructure by combining WSe2 and Bi2Se3,which is able to realize the simultaneous visible and near-infrared detection because of the complementary bandgaps of WSe2 and Bi2Se3(1.46 and 0.3 e V respectively).Thanks to the realigned band structure,the heterostructure shows an ultralow dark current below picoampere and a high tunneling-dominated *** photodetector based on our tunneling heterostructure exhibits a superior specific detectivity of 7.9×1012Jones for a visible incident of 532 nm and 2.2×1010Jones for a 1456 nm nearinfrared *** study demonstrates a new band structure engineering avenue for the construction of van der Waals tunneling heterostructures for high-performance wide band photodetection.

摘要：Photodetectors operating in the shortwave infrared region are of great significance due to their extensive applications in both commercial and military *** two-dimensional layered materials(2DLMs)are considered as the promising candidates for constructing nextgeneration high-performance infrared ***,the performance of 2DLMs-based photodetectors can hardly satisfy the requirements of practical applications due to their weak optical *** the present study,a strategy was proposed to design high-performance shortwave infrared photodetectors by integrating metalorganic frameworks(MOFs)nanoparticles with excellent optical absorption characteristics and 2DLM with high ***,this study demonstrated the practicability of this strategy in a MOF/2DLM(Ni-CAT-1/Bi_(2)Se_(3))hybrid heterojunction *** to the transfer of photo-generated carriers from the MOF to Bi_(2)Se_(3),the MOF nanoparticles integrated on the Bi_(2)Se_(3) layer can increase the photocurrent by 2-3 orders of *** resulting photodetector presented a high responsivity of 4725 A W^(−1) and a superior detectivity of 3.5×10^(13) Jones at 1500 *** outstanding performance of the hybrid heterojunction arises from the synergistic function of the enhanced optical absorption and photogating *** addition,the proposed device construction strategy combining MOF photosensitive materials with 2DLMs shows a high potential for the future high-performance shortwave infrared photodetectors.

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：左侧额中回(MFG)是汉字阅读脑机制研究发现的一个典型脑区,它表现出在汉字阅读中的特异激活,一种普遍的解释认为其负责了汉字独特的视觉空间加工。但是,该解释没有得到直接的证据支持。本研究操纵汉字材料的视觉呈现空间频率,使用功能性近红外光谱成像(fNIRS)技术对此问题进行探讨。通过构建3(字类型:真字、假字和非字)×3(空间频率:完整频谱、低空间频率和高空间频率)的重复测量实验设计,记录被试在完成重复刺激检测的one-back任务时MFG的血氧浓度变化。结果发现左侧MFG表现出显著的字类型主效应,即假字比真字和非字需要更多MFG的激活;而且,左侧MFG还表现出显著的字类型与空间频率的交互作用,即在低空间频率条件下假字比真字和非字具有更强的MFG激活,而在另两种频率条件下并没有发现字类型的显著激活差异。结果表明左侧MFG的确对汉字的空间信息敏感,尤其是在需要更多字形/正字法加工的假字条件下以及对低空间频率信息的加工上都需要更多MFG的激活。研究结果为左侧MFG参与汉字正字法信息的视觉空间加工提供了直接的证据。

摘要：大型水电站导流洞封堵永久堵头一般选择在围岩条件相对较好且与大坝防渗帷幕相交的洞段,堵头型式一般采用楔形结构。为了避免二次开挖,达到简化施工、加快进度的目的,乌东德水电站导流洞永久堵头采用直柱形结构型式。这要求准确查明堵头段衬砌混凝土、喷混凝土和围岩的接触情况。为此,选取具备研究条件的5号导流洞开展研究工作,采用钻孔取芯、彩电、声波测试、平面超声横波成像检测及室内试验等手段,查明了堵头段各接触面的接触状况。以测试及试验成果为基础,类比相似工程并结合地质条件,给出了堵头段各接触面的物理力学参数建议值,为堵头设计提供依据。这一研究方法及成果可为其他类似工程提供借鉴。

摘要：乌东德水电站共布置5条导流洞（其中左岸2条，右岸3条）。高、低洞洞身段断面呈城门洞型。断面尺寸分别为12m×16m和16．5m×24m。2012年2月乌东德水电站导流洞开始施工，落雪组因民组极薄层～薄层大理岩化白云岩、层面附绢云母构成的Ⅳ类围岩洞段按5层开挖，在第一层开挖过程中因民组Ⅳ类围岩洞段左顶拱普遍出现塌方，第二层和第三层开挖时，导流洞左右边墙变形位移急剧增大。通过研究导流洞Ⅳ类围岩地质条件及变形失稳模式，分析变形过程与开挖支护的关系。在此基础上优化设计方案，确保了导流洞的安全施工。

摘要：为给乌东德水电站尾水洞Ⅳ类围岩洞段选取适当的地下洞室衬砌形式,分析了该洞段围岩的岩石矿物组成、物理力学性质、结构面性状、岩体完整性及透水性等岩体特性,从地下水对围岩的软化作用和围岩渗透破坏方面评价了透水衬砌对围岩的影响。结果表明:Ⅳ类围岩洞段总体具有不易被地下水软化的特点,地下水对围岩稳定影响小,采用透水衬砌不会产生渗透破坏。研究成果可为尾水洞衬砌设计提供参考。

摘要：为实现农村公路养护管理智能化、决策科学化,以山东省农村公路为研究对象,构建了农村公路路网及桥梁典型养护方案、优先排序、资金测算等模型,研发了农村公路养护大数据分析平台,实现多源多层次细颗粒度数据融合和基于GIS地图的联动展示。该平台可为农村公路管养提供决策服务和技术支撑,为“四好农村路”高质量发展提供技术支持。