In-situ synthesis of zirconium oxycarbide by electroreduction of ZrO2/C in molten salt

Homogenous ZrC_xO_y powders have been successfully synthesized by in-situ electro-reduction of solid ZrO₂–C composite precursors in molten CaCl₂. The effect of applied cell voltage and molar ratio of ZrO₂ to C on preparation of ZrC_xO_y were investigated. The reduction pathway of the composite electrode was studied based on the analysis of intermediate products using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that ZrO₂ is firstly converted to CaZrO₃. The resulting CaZrO₃ is then reduced to ZrC_xO_y. The ZrC_xO_y formation is dramatically influenced by electrolysis voltage and molar ratio of ZrO₂ to C: a higher cell voltage and lower molar ratio of the ZrO₂ to C are more preferable for the formation of ZrC_xO_y powder. Homogenous ZrC_xO_y powders with particle size of ~100 nm are synthesized by ZrO₂/C starting elemental powders in CaCl₂ molten salt at 1123 K for more than 3 h, when the cell voltage is 3.0 V and the molar ratio of the ZrO₂ to carbon starting materials is 1:1.0.     

Synthesis and photoluminescent properties of high-efficient color-tunable Ba3Y2B6O15: Ce3+, Tb3+ phosphors

High-efficient Ce³⁺/Tb³⁺ co-doped Ba₃Y₂B₆O₁₅ phosphors with multi color-emitting were firstly prepared, and their structural and luminescent properties were studied by XRD Rietveld refinement, emission/excitation spectra, fluorescence lifetimes as well as temperature-variable emission spectra. Upon 365?nm excitation, the characteristic blue Ce³⁺ band along with green Tb³⁺ peaks were simultaneously found in the emission spectra. Moreover, by increasing concentration of Tb³⁺, a blue-to-green tunable emitting color could be realized by effective Ce³⁺→Tb³⁺ energy transfer. Furthermore, all Ba₃Y₂B₆O₁₅: Ce³⁺, Tb³⁺ phosphors exhibit high internal quantum efficiency of ~?90%, while the temperature-variable emission spectra reveal that the phosphors possess impressive color stability as well as good thermal stability (T₅₀ =?~?120?°C). The results indicate that these efficient color-tuning Ba₃Y₂B₆O₁₅: Ce³⁺, Tb³⁺ might be candidate as converted phosphor for UV-excited light-emitting diodes.     

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).     

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-     

老井复查评价技术在浅层油藏中的研究与应用

本文以靖安地区浅层老井为例,利用钻井、录井、测井、取心等资料,结合现代测井解释评价技术,对受当时技术条件限制被误判的储层进行再分析研究。制定可行的复查评价标准与流程,确定出油下限,优选补孔潜力井,并结合精细地质研究成果筛选建产目标区,达到挖潜增效和滚动增储的双重目的。对老区日后寻找新储量进行勘探开发具有十分重要的意义。     

中美欧建筑结构荷载规范对比研究

随着"一带一路"国际工程项目的持续推进,关于国内外建筑结构荷载规范的对比研究变得十分迫切.本文针对中国、美国和欧洲建筑结构荷载规范,从承载力极限状态和正常使用状态两个方面,对荷载组合的设计表达式与分项系数取值进行了系统研究.结合实际工程算例详细分析了中美欧荷载组合计算方法的异同,研究表明:中美规范计算结果接近,欧洲规范计算结果偏于保守,产生差异的主要原因在于不同规范的分项系数取值不同,部分规范引入调整系数以增大或减小某项荷载组合值.     

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.     

Fabrication and use of artificial superhydrophilic surfaces

Superhydrophilic surfaces have recently received some attention due, in large part to the intense interest on the antonymous field of superhydrophobicity. Imparting superhydrophilicity onto surfaces through coatings, texturing, or choice of materials appears to hold significant commercial promise for the protection for optical devices (e.g. anti-fogging), self-cleaning, and stain resistant paints and flooring and use in the area of ‘intelligent’ coatings. In this review, the fabrication and application of artificial superhydrophilic surfaces are discussed. The focus is on results reported over the past decade for these materials. The contents of this review are written to provide an introductory yet comprehensive overview of this emerging field.     

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。