Ultrasonic spray pyrolysis synthesis of Ag/TiO2 nanocomposite photocatalysts for simultaneous H2 production and CO2 reduction

Simultaneous photocatalytic hydrogen production and CO₂ reduction (to form CO and CH₄) from water using methanol as a hole scavenger were investigated using silver-modified TiO₂ (Ag/TiO₂) nanocomposite catalysts. A simple ultrasonic spray pyrolysis (SP) method was used to prepare mesoporous Ag/TiO₂ composite particles using TiO₂ (P25) and AgNO₃ as the precursors. The material properties and photocatalytic activities were compared with those prepared by a conventional wet-impregnation (WI) method. It was found that the samples prepared by the SP method had a larger specific surface area and a better dispersion of Ag nanoparticles on TiO₂ than those prepared by the WI method, and as a result, the SP samples showed much higher photocatalytic activities toward H₂ production and CO₂ reduction. The optimal Ag concentration on TiO₂ was found to be 2 wt%. The H₂ production rate of the 2% Ag/TiO₂–SP sample exhibited a six-fold enhancement compared with the 2% Ag/TiO₂–WI sample and a sixty-fold enhancement compared with bare TiO₂. The molar ratio of H₂ and CO in the final products can be tuned in the range from 2 to 10 by varying the reaction gas composition, suggesting a viable way of producing syngas (a mixture of H₂ and CO) from CO₂ and water using the prepared Ag/TiO₂ catalysts with energy input from the sun.     

某观光塔基础刚度的数值优化分析

本文采用有限元法对某观光塔结构在不同基础刚度下的力学特性进行了数值分析。计算模型采用多自由度悬臂梁体系,在一定范围内设定不同大小的基础水平刚度和转动刚度。数值模拟分析了基础刚度对该塔上部结构力学特性的影响,从而选择比较优化的基础刚度。并将实际采用的基础形式与塔体建立了整体模型,并进行比较分析,其研究结果可为该类型塔基础的优化设计提供参考依据。     

12R24.5 18PR无内胎全钢载重子午线轮胎的设计

介绍12R24.5无内胎全钢载重子午线轮胎的设计。结构设计:外直径1 130 mm,断面宽290 mm,行驶面宽度228 mm,行驶面弧度高7 mm,胎圈着合直径622.3 mm,胎圈着合宽度228 mm,断面水平轴位置(H1/H2)0.85,胎面采用3条曲折主花纹沟、变节距花纹设计,花纹深度17 mm,花纹周节数55,花纹饱和度68%。施工设计:胎面采用胎面胶、基部胶和过渡胶片结构,带束层采用3层带束层+2层0°带束层设计:1~#和2~#带束层采用3+9+15×0.22+0.15钢丝帘线,3~#带束层采用5×0.35HI钢丝帘线,0°带束层采用3×7×0.20HE钢丝帘线,胎体采用3+9+15×0.22+0.15钢丝帘线,采用三鼓一次法成型机成型,热板式硫化机硫化。成品轮胎性能试验结果表明,轮胎充气外缘尺寸、强度性能、耐久性能均符合国家标准要求,高速性能和接地印痕符合企业标准要求。     

Influence of ZnO interlayer on the performance of inverted organic photovoltaic device

Inverted organic photovoltaic devices with a structure of fluorine tin oxide (FTO)/ZnO/poly(3-hexylthiophene) (P3HT):[6,6]-phenyl C₆₁ butyric acid methyl ester (PCBM)/Ag were fabricated, in which ZnO interlayer serves as an electron selective layer. The ZnO interlayer includes three different nanostructures: polycrystalline seed layer, polycrystalline seed layer/loose nanopillars and polycrystalline seed layer/dense nanopillars. The influences of the different ZnO interlayers on the device performance were investigated. It is concluded that the polycrystalline seed layer/loose nanopillars offer more interfacial area with the P3HT:PCBM blends and acts as a continuous conducting path to the cathode. Our results demonstrate that effective infiltration of the blends into the ZnO nanopillars is critical for optimizing the device performance.     

无线通信基站雨衰检测及补偿方法

本文提供了一种5G毫米波基站针对雨衰的补偿方法,可以在特定的场景下对无线信号进行一定程度的补偿,减少极端大雨天气对无线通信的影响。基于实时检测基站周边的雨量环境,结合基站当前的覆盖场景和参数配置,制定补偿策略,并最终通过IR接口、MAC调度等方式实现优化策略的实现。该方法主要应用于将来的5G毫米波基站。     

“韩流”送来日用陶瓷的春天

如今,"韩流"已经不是一件多么新鲜的事情,"哈韩"也不再是几个人的个性演绎。韩国制造正在以不可阻挡的力量席卷着整个亚洲。在这股强烈的旋风中商机暗涌,针对目前日用陶瓷市场上畅销"韩式"餐具,从中得到启发和思考,从而探讨中国日用陶瓷的发展方向。     

Natively textured surface aluminum-doped zinc oxide transparent conductive layers for thin film solar cells via pulsed direct-current reactive magnetron sputtering

Natively textured surface aluminum-doped zinc oxide (ZnO:Al) layers for thin film solar cells were directly deposited without any surface treatments via pulsed direct-current reactive magnetron sputtering on glass substrates. Such an in-situ texturing method for sputtered ZnO:Al thin films has the advantages of efficiently reducing production costs and dramatically saving time in photovoltaic industrial processing. High purity metallic Zn-Al (purity: 99.999%, Al 2.0 wt.%) target and oxygen (purity: 99.999%) were used as source materials. During the reactive sputtering process, the oxygen gas flow rate was controlled using plasma emission monitoring. The performance of the textured surface ZnO:Al transparent conductive oxides (TCOs) thin films can be modified by changing the number of deposition rounds (i.e. thin-film thicknesses). The initially milky ZnO:Al TCO thin films deposited at a substrate temperature of ~ 553 K exhibit rough crater-like surface morphology with high transparencies (T ~ 80-85% in visible range) and excellent electrical properties (ρ ~ 3.4 × 10^− 4 Ω cm). Finally, the textured-surface ZnO:Al TCO thin films were preliminarily applied in pin-type silicon thin film solar cells.     

氧化铝微细颗粒絮凝沉降研究

用羧甲基纤维素、聚丙烯酰胺、硫酸铝和氯化铁四种絮凝剂进行氧化铝微细颗粒的絮凝沉降研究。试验结果表明：在适宜的参数条件下,四种絮凝剂均可显著提高氧化铝微细颗粒的沉降速度。根据沉降颗粒的形貌探讨了有机絮凝剂和无机絮凝剂的絮凝沉降机理     

天然气液化装置工艺危险性分析

分析了天然气液化装置的工艺危险性,认为其主要危险是火灾爆炸、物理性爆炸和LNG翻腾,并提出工艺设计需要采取的安全措施。     

基于海量扫频数据的用户感知提升策略及应用研究

本文主要针对无线网络优化工作中的扫频测试数据进行研究,挖掘扫频数据在无线安全性、无线定位应用和无线环境预警方面的延展性,并结合移动终端用户App应用数据的倾向性,形成一套用户感知提升策略,并提出了该策略的应用方向和设计方案。研究的目的在于让运营商的数据为用户服务,同时用户的反馈数据也能成为运营商的有利数据源。