Nickel supported over MCM-41 coated ceramic membrane for steam reforming of real tar

A novel catalyst, Nickel supported over MCM-41 coated ceramic membrane (NMC), was developed using coating method and deposition-precipitation method and applied for steam reforming of real tar in fixed bed. The effects of reaction conditions such as Ni loading amount, reaction temperature and mass ratio of steam to tar were also studied. The good dispersion of Ni nanoparticles and the strong interaction between Ni particles and the support were identified by BET, XRD, H₂-TPR and SEM/EDS, resulting in the excellent performance of NMC catalysts. Maximum tar conversion of 96.4% and H₂ yield of 98.7 mmol g^?1 were obtained using 20NMC with a mass ratio of steam to coal tar of 2 at 800 °C. Moreover, 20 NMC exhibited a good stability in 10 h of lifetime test and the resistance of graphitic carbon formation prone to easier regeneration of catalysts illustrated by Raman spectroscopy. It indicates that the utilization of NMC catalysts for tar steam reforming is a promising way.     

Design of 25 Gbit/s half-rate CDR with 1:2 demultiplexer for 100 GbE optical interconnects

A 25 Gbit/s clock and data recovery(CDR) circuit with 1:2 demultiplexer for 100 Gbit/s Ethernet(100 Gb E) optical interconnects has been designed and fabricated in Taiwan Semiconductor Manufacture Company(TSMC) 65 nm complementary metal-oxide-semiconductor(CMOS) technology. A novel quadrature voltage-controlled-oscillator(QVCO) structure adopts two pairs of transconductance cell and inverters to acquire rail-to-rail output swing. A half-rate bang-bang phase detector adopts four flip-flops array to sample the 25 Gbit/s input data and align the data phase, so the 25 Gbit/s data are retimed and demultiplexed into two paths 12.5 Gbit/s output data. Experimental results show that the recovered clock exhibits a peak-to-peak jitter of 7.39 ps and the recovered data presents a peak-to-peak jitter of 7.56 ps, in response to 312-1 pseudorandom bit sequence(PRBS) input. For 1.2 V voltage supply, the CDR circuit consumes 92 m W(excluding output buffers).     

Synergetic improvement strategy on thermoelectric performance of CuAlO2 compacts

We fabricated Sr and Ca-doped CuAlO₂ compacts from the mixed powder of CuO, Cu₂O, Al₂O₃, and SrO or CaO by multi-pass hot pressing followed by spark plasma sintering (SPS). The XRD results showed the reaction of CuO, Cu₂O and Al₂O₃ was rather complete and only CuAlO₂ single phase was formed when the additive amount of SrO or CaO was appropriate. Multi-pass hot pressing increased the relative density and the usage of plate-like Al₂O₃ as reaction raw material enhanced the orientation degree. In spite of performance improvement conflicts through elemental doping, density increase and orientation improvement, the measurement on the thermoelectric performance indicated that the electrical resistivity, Seebeck coefficient, power factor, dimensionless figure of merit (ZT) were improved to varying degrees through the synergetic action of elemental doping, density increase, and orientation control. The highest power factor and ZT of the Ca-doped CuAlO₂ compacts reached 1.54?×?10^?4 W?m^?1 K^?2 and 0.015 at 973?K, respectively. The thermoelectric performance was higher than those of CuAlO₂ at the same temperature in published work before.     

Preparation of Silver Nanowires via a Rapid,Scalable and Green Pathway

Rapid synthesis of silver nanowires(Ag NWs) with high quality and a broad processing window is challenging because of the low selectivity of the formation of multiply twinned particles at the nucleation stage for subsequent Ag NWs growth.Herein we report a systematic study of the water-involved heterogeneous nucleation of Ag NWs with high rate(less than 20 min) in a simple and scalable preparation method.Using glycerol as a reducing agent and a solvent with a high boiling point,the reaction is rapidly heated to 210 ℃ in air to synthesize Ag NWs with a very high yield in gram level.It is noted that the addition of a small dose of water plays a key role for obtaining highly pure Ag NWs in high yield,and the optimal water/glycerol ratio is0.25%.After investigating a series of forming factors including reaction temperature and dose of catalysts,the formation kinetics and mechanism of the Ag NWs are proposed.Compared to other preparation methods,our strategy is simple and reproducible.These Ag NWs show a strong Raman enhancement effect for organic molecules on their surface.     

WIRELESS BODY-AREA NETWORKS

The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless person-     

FINE:Future Internet iNnovation Environment

This article introduces FINE(Future Internet iNnovation Environment) project,which is supported by National High-tech R&D Program( "863" Program) of China.     

高效固体缓释型阻垢剂的研制及性能分析

针对大庆油田集输管道腐蚀结垢现象,以主剂、分散剂、特殊缓蚀阻垢剂和载体配制固体缓蚀阻垢剂,通过复配试验筛选出适合其采出液水质的药剂,并对其缓蚀和阻垢性能进行分析。结果表明:加注药剂后的管道钢腐蚀速率为0.070mm/a,远低于未加注前的0.310mm/a;阻垢效果15天内稳定,阻垢率约为91%,阻垢性能良好;缓释速率为约每10天溶解8%,加注周期约为3个月。所制备药剂性价比高,缓蚀阻垢综合性能良好,可作为油田水驱采出液专用缓蚀阻垢药剂。     

颗粒在椭圆形回转干馏炉内运动分析

通过实验研究颗粒在不同椭圆滚筒内的运动情况,分析了不同填充率、不同转速和不同颗粒粒径对其的影响。由实验得出:颗粒在椭圆不同位置的运动情况并不一致,随着长短轴之比变大,运动趋于平缓;填充率降低会引起颗粒运动模式过渡区间变大,进入小瀑布模式所需转速增加;颗粒粒径增大,颗粒在筒内受重力、摩擦力的影响变得更加明显,在长轴垂直水平位置,所受惯性影响更加显著,并出现明显的多种模式相结合的运动形式。     

基于Fluent的水击泄压阀阻力系数研究

针对长输油管道广泛应用的水击泄压阀,应用CFD方法对其内部流场进行了分析计算。按照实际泄压阀的结构,建立了简化后的二维流场几何模型,根据模拟的流场压力分布计算不同开度、不同开启压力和不同管径下泄压阀的阻力系数,指出泄压阀的阻力系数与开度、管径有关,开启压力对泄压阀的阻力系数几乎没有影响。     

激光粒度仪分级测定水煤浆粒度分布的研究

为确定多种磨矿产品级配制得水煤浆样品的粒度分布,文章提出了分级测定水煤浆粒度的方法,已知各磨矿产品的粒度分布,通过分级拟合的方法得到不同质量比级配样品的粒度分布。结果表明:分级计算方法得到的煤样粒度分布可以准确反映出级配样品的峰型,且粒度测试结果较为准确。