Fabrication of ZnO nanorod-based hydrogen gas nanosensor

We report a first work on nanofabrication of hydrogen nanosensor from single ZnO branched nanorods (tripod) using in-situ lift-out technique and performed in the chamber of focused ion beam (FIB) system. Self-assembled ZnO branched nanorod has been grown by a cost-effective and fast synthesis route using an aqueous solution method and rapid thermal processing. Their properties were analyzed by X-ray diffraction, scanning electron microscopy, energy dispersion X-ray spectroscopy, transmission electron microscopy, and micro-Raman spectroscopy. These analyses indicate high quality ZnO nanorods. Furthermore, our synthesis technique permits branched nanorods to be easily transferred to other substrates. This flexibility of substrate choice opens the possibility of using FIB system for handling.

The main advantage of the proposed in-situ approach is a controllable lift-out procedure which permitted us to obtain a 90% success rate for building nanodevices. The fabricated nanosensor uses only single self-assembled ZnO branched nanorod (tripod) to gauge the 150 ppm H₂ in the air at room temperature. The hydrogen sensitivity is in the range of 0.6–2% depending on which two branches to use. The nanosensor has selectivity against other gases such as O₂, CH₄, CO and LPG, which shows sensitivity of <0.02%. The single ZnO branched nanorod sensor can operate at low power of <5 μW.     

ATN路由器中路由算法IS-IS的研究与改进

路由算法和协议在路由器中的地位至关重要,文章对路由算法IS-IS及路由算法的效率进行研究和改进,提高了路由器的处理能力和稳定性。     

基于协方差分析描述函数技术的弹道导弹落点预报

针对采用Monte-Carlo方法对非线性系统进行统计分析效率低下的问题,将协方差分析描述函数法(CADET)应用于弹道导弹落点预报与精度分析.介绍CADET方法的统计线性化思想,提出一种针对一阶可微随机变量函数的统计线性化方法,建立弹道导弹被动段的均值和方差计算的CADET模型.该方法通过一次计算就可得到随机变量数字...     

脉冲氙灯瞬态放电特性实时检测

随着惯性约束核聚变（ICF）的发展,对激光驱动器提出了很高的要求。本文研究了脉冲氙灯瞬态在线检测系统对脉冲氙灯放电电压、电流和发光强度进行实时监测的方法和系统的结构,结合氙灯的瞬态放电特征,利用光电隔离、光纤传输、高速A／D采样等技术,获取氙灯瞬态放电 数据。有效的实现了弱电系统对强电系统的远程测控,为大型激光驱动器能源系统的自动测控打下良好的基础。     

一种基于最优控制的网络管理整体策略

随着当前运营商所运营接入网络制式的不断发展,网络管理的负担大大增加,网络管理变得更加频繁。在这种情况下,网络管理不能只保证网络系统处于良好状态,需要同时保证网络状态调整的过程最优。从控制论的角度研究了这一问题,基于最优控制理论提出了最优化网络管理方法。本文的研究成果已经在天津联通的接入网络中得到了证实,相关研究对自动控制理论与网络管理的相关研究有着十分重要的意义。     

CTM和个人通信业务

本文介绍了ＥＴＳＩ最近提出的ＣＴＭ的概念;即基于ＤＥＣＴ技术在ＰＳＴＮ,ＩＳＤＮ的基础上结合ＩＮ技术实现个人通信业务,并给出了ＣＴＭ的网络结构,分析了ＣＴＭ个人通信业务的市场形势,最后介绍了ＣＴＭ在欧洲的发展及应用现状。     

基于光谱控制与色散优化的飞秒啁啾脉冲放大系统

飞秒激光在工业加工、精密测量、军事国防、科学研究等领域具有广阔的应用前景。报道了基于光谱控制与色散优化的高功率、高脉冲质量飞秒啁啾脉冲放大系统。利用与压缩器色散量相匹配的色散可调啁啾布拉格光纤光栅(CFBG)作为展宽器,通过微调CFBG色散量补偿系统的残余色散使整个系统的净色散趋于零;同时引入光谱滤波等手段,保证入射到主放大器之前的脉冲光谱形状不发生畸变,避免了放大过程中脉冲质量的劣化。最终获得了重复频率为50 MHz、平均功率为24 W、脉冲宽度为198 fs的高脉冲质量飞秒激光输出。     

Embedding RhPx in N,P Co‐Doped Carbon Nanoshells Through Synergetic Phosphorization and Pyrolysis for Efficient Hydrogen Evolution

Rational design and controllable synthesis of well‐defined nanostructures with high stability and Pt‐like activity for hydrogen evolution reaction (HER) are critical for renewable energy conversion. Herein, a unique pyrolysis strategy is demonstrated for the synthesis of RhP_x nanoparticles (NPs) in N, P co‐doped thin carbon nanoshells (RhP_x@NPC nanoshells) that display high electrocatalytic activity and stability over a wide pH range. This strategy involves simultaneous phosphorization and pyrolysis processes that can produce highly‐dispersed RhP_x NPs within N, P co‐doped carbon nanoshells and at the same time induce thinning of carbon nanoshells from inside out. The resulting RhP_x@NPC nanoshells not only possess Pt‐like activity for HER with low overpotentials to achieve 10 mA cm^?2 (22 mV in 0.5 m H₂SO₄, 69 mV in 1.0 m KOH, and 38 mV in 1.0 m phosphate buffered saline (PBS)) but also provide long‐term durability in a wide pH range. The remarkable HER performance of RhP_x@NPC nanoshells is ascribed to the high surface area, abundant mesoporosity, strong catalyst–support interaction, ultrathin carbon encapsulation, and N, P co‐doping. This work provides an effective strategy for designing heterostructured electrocatalysts with high catalytic activity and stability desired for reactions that may occur under harsh conditions.     

磁控溅射法生长CeO2/Si薄膜及其发光性质

利用反应磁控溅射法对CeO2薄膜的生长规律进行了研究.通过实验发现,溅射时氧气和氩气的比例对薄膜的成分和晶体质量有很大影响.在室温下测试了CeO2薄膜的PL谱,结果表明CeO2薄膜的发光主要来自于氧缺陷.     

Peer-to-peer electricity trading system: smart contracts based proof-of-benefit consensus protocol

Wireless Networks - Nowadays, people trade electricity through centralized companies or organizations which is vulnerable to cyber attacks and incapable of coping with increasing demands from...