Versatile Graphene‐Promoting Photocatalytic Performance of Semiconductors: Basic Principles,Synthesis, Solar Energy Conversion,and Environmental Applications

Graphene‐semiconductor nanocomposites, considered as a kind of most promising photocatalysts, have shown remarkable performance and drawn significant attention in the field of photo‐driven chemical conversion using solar energy, due to the unique physicochemical properties of graphene. The photocatalytic enhancement of graphene‐based nanocomposites is caused by the reduction of the recombination of electron‐hole pairs, the extension of the light absorption range, increase of absorption of light intensity, enhancement of surface active sites, and improvement of chemical stability of photocatalysts. Recent progress in the photocatalysis development of graphene‐based nanocomposites is highlighted and evaluated, focusing on the mechanism of graphene‐enhanced photocatalytic activity, the understanding of electron transport, and the applications of graphene‐based photocatalysts on water splitting, degradation or oxidization of organic contaminants, photoreduction of CO₂ into renewable fuels, toxic elimination of heavy metal ions, and antibacterial applications.     

抽水蓄能电站中水力干扰下的过渡过程及其稳定问题的研究

高水头抽水蓄能电站中，常采用一洞多机系统，所以机组之间水力联系紧密，本文建立了对水力干扰进行过渡过程计算所必须的既能进行大波动计算又可进入小波动的数学模型，并编制了计算程序，通过计算研究了部分机组停机过程中，其余机组在水力干扰下的过渡过程及稳定问题。     

基于LPC2104的视频切换矩阵设计

本文介绍一种以AD81084作为视频切换器件,以LPC2104ARM微控制器作为控制单元的智能型视频切换器,并简述了其工作过程、硬件构成、软件设计。     

A differential pulsewidth control loop for high-speed VLSI systems

For those adopting double data rate technology systems, the precise system timing plays a crucial role since both rising and falling edges of the system clock signal are used to sample the input data. Due to this requirement, it is necessary to accurately maintain the duty cycle of the clock signal at 50%. For a multistage clock buffer, a pulsewidth control loop (PWCL) circuit was therefore proposed to adjust the duty cycle of its output signal. This paper is aimed at introducing a new proposed differential PWCL (DPWCL) together with investigating its mechanism through a comprehensive theoretical analysis. By taking advantage of a differential topology, the dc offset in generating the control voltage can be removed thereby improving the duty cycle control accuracy. Moreover, the proposed DPWCL employs a low-pass filter to generate the reference voltage so that the DPWCL does not necessitate a 50% duty cycle reference clock.     

Graphene Oxide‐Cyclic R10 Peptide Nuclear Translocation Nanoplatforms for the Surmounting of Multiple‐Drug Resistance

Multidrug resistance resulting from a variety of defensive pathways in cancer has become a global concern with a considerable impact on the mortality associated with the failure of traditional chemotherapy. Therefore, further research and new therapies are required to overcome this challenge. In this work, a cyclic R10 peptide (cR₁₀) is conjugated to polyglycerol‐covered nanographene oxide to engineer a nanoplatform for the surmounting of multidrug resistance. The nuclear translocation of the nanoplatform, facilitated by cR₁₀ peptide, and subsequently, a laser‐triggered release of the loaded doxorubicin result in efficient anticancer activity confirmed by both in vitro and in vivo experiments. The synthesized nanoplatform with a combination of different features, including active nucleus‐targeting, high‐loading capacity, controlled release of cargo, and photothermal property, provides a new strategy for circumventing multidrug resistant cancers.     

Active layer self-protection process for organic field-effect transistors

y in air.     

等离子体激励对飞行器流场影响的数值研究

针对传统飞行器控制方式的缺点,采用小尺度等离子体流动控制技术对飞行器流场影响进行研究。在前人的实验模型及飞行参数进行研究的基础上建立三维模型,采用数值仿真方法,研究了等离子体激励器位置和注入能量大小对飞行器流场及表面压力分布的影响。仿真结果表明：等离子体与边界层的相互作用可改变飞行器外部激波的初始结构,并在激励位置附近形成局部高压区;随着注入能量的增加,高压区峰值及作用范围分别扩大;等离子体激励产生的扰动具有三维传播特性,对飞行器侧壁面甚至对整个壁面周向压力分布产生影响。     

Morphology Transformation Pathway of Block Copolymer-Directed Cooperative Self-Assembly of ZnO Hybrid Films Monitored In Situ during Slot-Die Coating

Cooperative self-assembly (co-assembly) of diblock copolymers (DBCs) and inorganic precursors that takes inspiration from the rich phase separation behavior of DBCs can enable the realization of a broad spectrum of functional nanostructures with the desired sizes. In a DBC assisted sol–gel chemistry approach with polystyrene-block-poly(ethylene oxide) and ZnO, hybrid films are formed with slot-die coating. Pure DBC films are printed as control. In situ grazing-incidence small-angle X-ray scattering measurements are performed to investigate the self-assembly and co-assembly process during the film formation. Combining complementary ex situ characterizations, several distinct regimes are differentiated to describe the morphological transformations from the initially solvent-dispersed to the ultimately solidified films. The comparison of the assembly pathway evidences that the key step in the establishment of the pure DBC film is the coalescence of spherical micelles toward cylindrical domains. Due to the presence of the phase-selective precursor, the formation of cylindrical aggregates in the solution is crucial for the structural development of the hybrid film. The pre-existing cylinders in the ink impede the domain growth of the hybrid film during the subsequent drying process. The precursor reduces the degree of order, prevents crystallization of the PEO block, and introduces additional length scales in the hybrid films.     

数字播控系统若干技术问题的探讨

随着数字技术和计算机技术的迅猛发展 ,电视技术的数字化进程十分迅速。两年前尚未被人们提上议事日程的“电视台播控系统数字化”问题 ,眼下已成为各家电视台必须考虑的当务之急。部分电视台已完成了播控系统的数字化建设和改造。目前较为常见的是用数字切换台播出系统取代模拟切换台播出系统 ,也有用数字矩阵播出系统取代模拟切换台或模拟矩阵播出系统的。模拟放像机被硬盘服务器或数字放像机 (兼容模拟 )所取代。在前者情况下 ,传统磁带放像机起着节目上载机及作为应急播出机的作用。总控系统则由原来的模拟视音频矩阵改造为数字矩阵 (采…     

多媒体教学资源云共享平台的构建研究

随着云计算技术的发展,多媒体教学资源的云共享平台的建设引起了人们的高度重视。将多媒体教学资源与云平台建设结合起来,可以有效的解决在多媒体教学资源在网络学习平台建设中存在的种种问题,提高多媒体教学资源的利用率。本文主要研究,多媒体教学资源的特点,多媒体教学资源网络平台建设中存在的问题,云计算和云共享理论、多媒体教学资源云共享平台的构建。