对精馏塔浮阀塔盘进行了水力学实验,测定直径2m、BDH浮阀塔盘的清液层高度、雾沫夹带和塔盘压降等水力学数据.建立了与实验塔盘结构尺寸一致的几何模型,借助Fluent软件对实验浮阀塔盘进行了气液流场的CFD模拟,从微观层面考察板上气液两相的流动状态,清液层高度的模拟值与实验测量数据基本吻合.在经过验证模拟准确性的基础上,分析了BDH浮阀塔盘在运行稳定、模拟达到稳态时,塔盘上液相逆行流体积分数较大、液相返混情况明显的问题,提出了在BDH浮阀塔盘局部流场不理想位置设置ADV浮阀.在相同操作条件下,运用Fluent软件对优化后的浮阀塔盘进行分析,将改进前后的数据进行定性定量比较和分析,所得结果对于工业装置中浮阀塔盘的结构优化设计具有一定的理论指导意义.

Felicitously incorporating noble metals with some transition metals to fabricate composite nanoagents with diverse shape and microarchitecture is a more promising solution for obtaining highly effective and cost-cutting catalyst. Herein, we report a facile and flexible synthesizing tactics, or Galvani substitution modulated self-assembly protocol, to fabricate Cu nanowire (core)-Pt nanoparticle (shell) unique microarchitecture (Cu-NWs@Pt) with porously hiberarchy. The comprehensive characterizations reveal that as-fabricated bimetallic nanowires with average aspect ratio of ca. 80 and apparent diameter of ca 60 nm, hold the razor-thin Cu-Pt alloy sublayer in the metallic contact interface, with the prebuilt Cu nanowires cladded by orderly oriented Pt nanograins to form loose, porous and stratiform structure. The thickness and microarchitecture of the Pt shell could be duly regulated by adjusting dosage of the metal precursors and substituting time. The verified formation of electronic synergic effect in the bimetallic nanoagents avails the adsorption of H to form metal-H species, leading to enhance the catalytic activity. Their catalytic ability overall increases with rising of Pt/Cu molar ratios, of which the Cu0.6Pt0.4 even exceeds Pt-NPs, with a turnover frequency of 77.26 center dot min(-1) and apparent activation energy of 30.25 kJ center dot mol(-1), and maintaining 89% of the incipient catalytic ability after 5 recycling runs. (c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

A flexible and mild fabricating protocol, i.e., stepwise reduction and in situ loading route, is proposed to modulate ordered growing and dispersive depositing of Pt@Cu bimetal layered nanostructure on titanium dioxide nanotubes (TiO 2 ‐NTs) via reasonably regulating addition sequence and dosage for the reactants and additives. Comprehensive characterizations demonstrate that most of the Cu core‐Pt shell nanocrystals with a mean size of 10 nm evenly disperse on the surface of TiO 2 ‐NTs, and a small number of nanocrystals permeate into the nanotubes. In comparison to TiO 2 ‐NTs, the specific surface area declines after loading bimetals, with the pore size distribution shifting from micropores to mesopores. The catalytic activity of the Pt@Cu(x)/TiO 2 for hydrolytic hydrogen evolution presents an increasing tendency as the bimetal loadings rise, each surpassing that of the bare bimetal nanocrystals. The H 2 generating rate gradually rises with temperature increment. The AB hydrolysis catalyzed by Pt@Cu(9%)/TiO 2 at the given temperatures (293–313 K) is affirmed as a first‐order reaction, with apparent activation energy of 28.43 kJ mol −1 and TOF value of 107.27 min −1 . The catalyst Pt@Cu(9%)/TiO 2 unfolds exceptionally high stability, remaining 91% initial catalytic activity after five cycling use.

以氯化铜为铜源,葡萄糖为还原剂,十六胺和十八胺为封端剂,通过水热还原技术制备Cu纳米线,探讨反应温度、反应时间、还原剂配比和封端剂摩尔比对Cu纳米线形貌(长径比)的影响.结果表明,最优工艺条件:还原剂配比0.5,封端剂摩尔比0.4/0.8,反应温度110℃,反应时间6 h.产物清洗方式为沉降-分层-热液洗涤.在全优工艺条件下制得的Cu纳米线平均长径比>95,线径均值为26 nm,纳米线占比超过90％.

通过阳极氧化在金属钛上生长氧化钛(TiO2)纳米管阵列(NTAs),再经氨-氮化制得氮化钛(TiN)纳米管阵列.利用多电流阶跃法,使金属镍(Ni)均匀沉积在TiN-NTAs表面,形成多孔Ni@TiN-NTAs电极.通过等离子溅射,在电极上沉积Au层,可分别获得Ni@TiN-NTAs、Au@TiN-NTAs和Au/Ni@TiN-NTAs系列微结构复合电极.借助X射线衍射(XRD)、扫描电镜(SEM)和能谱分析(EDS)等手段对各产物进行了综合表征,并分别研究了这些电极在偏硼酸钠(NaBO2)碱性溶液中的电化学行为.研究结果表明:所得TiO2和TiN纳米管孔道结构规则,物相纯度较高,对过渡金属(Ni、Au)具有良好的负载和分散作用.在给定电解条件下,Au/Ni@TiN-NTAs表现出较低的电催化活性,但3种电解产物中均未检测到BH-4.