川芎挥发油化学成分GC/MS分析

使用水蒸气蒸馏法提取川芎中的挥发油,利用气相色谱-质谱联用技术对川芎化学成分进行分离鉴定,采用色谱峰面积归一化法确定各成分的相对含量。分析结果表明,共分离出53种组分,鉴定了其中的34个组分,占挥发油组分总量的64.42%。     

基于局部光照一致性约束的准稠密匹配方法

稠密匹配是基于立体视觉重建密集三维点云的关键技术,其中误匹配点的剔除是保证匹配准确率的重要手段.针对稠密匹配过程中搜索空间大,易出现误匹配的问题,提出了基于局部光照一致性约束的准稠密匹配方法.该方法将已知匹配点作为种子点,根据种子点及其邻域提供的影像约束进行匹配扩散,从而得到种子点邻域内的匹配点,进而实现图像之间的准稠...     

DVB-C接收机中自适应均衡器的新设计

着重讨论一种全新的DFE与盲均衡相结合的自适应均衡器的设计,对于符合DVB—C标准的QAM信号,在输入存在多径、频偏及加性噪声的情况下,采用此设计无须借助于训练序列或导频即可成功对信道进行自适应均衡以抵消ISI,并能自动切换捕获和跟踪模式,仿真效果良好。此外还能在一定范围内对输入的符号功率进行调整以降低AGC模块的设计要求。     

Mo Back Contact for Flexible Polyimide Substrate Cu（In,Ga）Se2 Thin-Film Solar Cells

A dc magnetic sputtering process is applied to growth of a Mo back. contact layer onto the flexible polyimide （PI） and rigid soda-lime glass （SLC） substrates. The structural and electrical properties of the Mo layer coated on the two kinds of substrates are investigated by x-ray diffraction （XRD） and Hall effect measurements. The results show that the Mo layer on SLG indicate more better crystal quality and lower resistivity than that on the PI sheets. In contrast to the SLG substrate, the resistivity of the Mo layer on PI is increased by the vacuum annealing process at the substrate temperature of 450℃ under Se atmosphere, which is attributed to the cracked Mo layer induced by the mismatch of the coefficient of thermal expansion between PI and Mo material. The Cu（In,Ga）Se2 （CIGS） solar cells based on the PI and SLO substrates show the best conversion efficiencies of 8.16% and 10.98% （active area, 0.2cm^2）, respectively. The cell efficiency of flexible CIGS solar cells on PI is limited by its relatively lower fill factor caused by the Mo back contact.     

Non-Thermal Photon Emission from Shell-Type Supernova Remnants

We study the non-thermal photon emission from shell-type supernova remnants （SNRs） in the frame of a two-zone model. In this model, the sites of acceleration, escape and subsequent radiation of particles （both electron and proton） are divided into acceleration and escape zones, respectively. The particle distributions consist of two components, one is produced inside the acceleration zone, the other in the escape zone. We apply this model to two young and one old shell-type SNRs and show that the observed multi-waveband photon spectra for the three SNRs can be explained well in this model and high-energy γ-rays from these SNRs may have hadronic origins.     

CO_2捕集过程中钙基吸收剂吸碳反应本征动力学

本文通过严格控制实验条件,消除内扩散和外扩散的影响,对两种CaO质量分数均为75%的合成钙基吸收剂进行了本征动力学实验。通过晶粒模型分析,找到了完全由表面反应控制的本征动力学阶段,分析其本征反应动力学特性,得到本征反应速率常数k_s和活化能E,并与早期的研究结果进行了对比分析。研究表明:两种合成吸收剂的活化能均小于石灰石吸碳反应的活化能;合成吸收剂的吸碳反应速率与石灰石分解CaO的吸碳反应速率具有相同的数量级。本研究同时得到了反应动力学控制阶段吸碳反应速率与驱动力CO_2分压之间的关系。     

三维多孔泡沫石墨烯的制备与应用研究进展

泡沫石墨烯是一种新型的碳基化工材料,具有独特的三维连通网络结构和优异的力学、热学、电学和化学稳定性能。本文综述了三维多孔泡沫石墨烯的制备与应用研究进展,主要介绍其水热法和化学气相沉淀制备法以及其作为催化材料、检测材料及电极材料的应用研究现状,并探讨了该领域亟待解决的重要问题和未来发展前景。     

The effects of Na on the growth of Cu2ZnSnSe4 thin films using low-temperature evaporation process

Cu2ZnSnSe4 (CZTSe) absorbers were deposited on borosilicate glass substrate using the low-temperature process, and different Na incorporation methods were applied to investigate the effects of Na on the CZTSe growth. Na was diffused into some of the absorbers after growth, which led to strongly improved device performance compared with Na-free cells. With the post-deposition treatment, the effect of Na on CZTSe growth was excluded, and most of Na was expected to reside at grain boundaries. The conversion efficiency of the completed device was improved due to the enhancement of open circuit voltage and fill factor. The efficiency of 2.85% was achieved at substrate temperature as low as 420 oC.     

利用无线物联网技术实现智能电力计量

为了实现对分散接入电力计量系统的终端智能电表实施数据读取和有效管理,文中提出了采用低功率无线网(LPWAN)技术,将终端智能电表接入数据网关和电力私有云实现智能电力计量的技术方案。该方案采用了LoRa无线模块实现电力计量数据的双向交互,具有运行可靠、低成本、低功耗、远程接入等优势。此外,文中还重点介绍将如何利用新兴的LPWAN技术帮助构建智能电能无线接入的解决方案,展示了用于智能电表端到端LoRa连接的系统实现。     

First principles calculation of the electronic-optical properties of Cu2MgSn(SxSe1-x)4

Based on the density functional theory with hybrid functional approach,we calculated the structural,electronic,and the optical properties of Cu2MgSn(S1-xSex)4(CMTSSe),an potential photovoltaic material for thin film solar cells.The calculation reveals a phase transition from kesterite to stannite structure when Zn atoms are substituted by Mg atoms.In particular,the S-to-Se ratio can determine the energy splitting between the electronic states at the top of the valence band.The band gaps of CMTSSe can be tuned in the ranges of 1.01-1.58 eV.Calculated optical properties and tunable band gaps make them beneficial for achieving band-gap-graded solar cells.