Comparative Study on Catalytic Performances for Low-temperature CO Oxidation of Cu–Ce–O and Cu–Co–Ce–O Catalysts

Two series of Cu–Ce–O and Cu–Co–Ce–O catalysts were prepared by co-precipitation method. The prepared catalysts were characterized by XRD, IR, TPR, XPS, BET and ICP-AES. The catalytic activities of the catalysts for low-temperature CO oxidation were evaluated through a microreactor-GC system. TPR results indicate that the addition of cobalt to the Cu–Ce–O can increase the dispersion of copper oxide, and the interaction between cobalt and copper can enhance the reducibility of each other. XPS analysis show that Ce⁴⁺, Cu²⁺, along with Co₃O₄, are present on the surface of Cu_0.4Co_0.6Ce₄ catalyst. The Co/Cu atomic ratio and the calcination temperature have significant effect on the activities of the catalysts. Compared with Cu₁Ce₄ catalyst, the Cu_0.4Co_0.6Ce₄ catalyst has better activity and thermal stability.     

CuO‐filled aminomethylated polysulfone hybrid membranes for deep desulfurization

CuO‐filled aminomethylated polysulfone hybrid membranes were prepared for sulfur removal from gasoline. The as‐prepared membranes were characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X‐ray diffraction (XRD). The separation performance of the hybrid membranes was evaluated by pervaporation (PV) separation of n‐heptane/thiophene binary mixture. CuO‐filling leads to a decrease in permeation flux. The sulfur‐enrichment factor increased first and then decreased with increasing CuO loading, and it is worth noting that there is a rebound in enrichment factor above 8 wt % CuO loading. Influencing factors such as nitrogen content, feed temperature, sulfur content, and various hydrocarbons on membrane PV performance were also evaluated. Permeation flux of 23.9 kg·μm·m^?2·h^?1 and sulfur‐enrichment factor of 3.9 can be achieved at 4 wt % CuO loading in PV of n‐heptane/thiophene binary mixture with 1500 μg·g^?1 sulfur content. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3718–3725, 2013     

再生骨料透水混凝土体积法配比设计关键参数的优化选择

以再生骨料配制的透水生态混凝土为研究对象,用体积法进行配合比设计并调整不同的配比参数,研究保证再生骨料配制透水生态混凝土透水性和强度的最佳配比参数,并比较再生骨料与天然骨料配比设计中参数选择的异同。     

1，1，1，3，3-五氟丙烷的合成技术研究

1,1,1,3,3-氟丙烷（HFC-245fa）是一种性能优异的ODS替代品,可用于发泡剂、制冷剂、清洗剂、热传导介质及气溶胶推进剂等,具有很好的发展前景。全面论述了多条原料工艺经过气、液相法单独合成或联产HFC-245fa的技术研究进展,并对其前景和合成工艺进行了详细的分析讨论。     

Single-handed helical polyethers synthesized via anionic polymerization of optically active 3-(9-alkylfluoren-9-yl)propene oxides

A series of optically active 3-(9-alkylfluoren-9-yl)propene oxides were synthesized by the reaction of 9-alkylfluoren-9-yllithium with the optically active epichlorohydrin at −70 °C and polymerized using KOH as an initiator. The molecular weight of the poly(3-(9-alkylfluoren-9-yl)propene oxide)s is larger than that of poly(4,4,4-triphenyl-1-butene oxide), which had been proved to take stable helical conformation in solution, and their molecular weight distributions were narrower (M_w/M_n = 1.02 to 1.09) than poly(4,4,4-triphenyl-1-butene oxide). By investigating of chiroptical properties of a series of polymers derived from optically active epoxide, it is suggested that the poly(3-(9-alkylfluoren-9-yl)propene oxide)s keep one-handed helical conformation in solution.     

膨胀石墨填充SBS复合材料的界面相互作用

膨胀石墨（ＥＧ）填充量小于２５％时,ＥＧ／ＳＢＳ复合材料的拉伸强度随ＥＧ充量的增加而增加,最大拉伸强度达２７．８ＭＰａ;而在ＥＧ填充量为１０％时,复合材料的扯断伸长率达到最大值（７８５％）,随后开始下降。用二甲苯作溶剂,在１４５℃抽提ＥＧ／ＳＢＳ复合材料２４ｈ后,复合材料中形成了稳定的交联结构,同时,凝胶含量随ＥＧ填充量的增加而增加。由此说明复合物中ＥＧ与ＳＢＳ之间产生了强烈的界面相互作用。ＤＭＡ     

表面张力引起的涂层弊病(Ⅱ)

３表面张力引起的涂层弊病［３～５］表面张力引起的涂层弊病在溶剂型涂料中更为常见。在水性涂料中 ,由于总是采用表面活性剂 ,使涂料的表面张力较为恒定 ,弊病产生的起因与表面张力的关系相对较少。３．１对流窝 (贝纳尔德窝 )当溶剂在湿涂层表面挥发时 ,将产生两种作用 :即由于溶剂挥发时吸热 ,使挥发中心附近温度降低 ;另外挥发中心附近的颜料和成膜物的浓度增大。这两种作用都使挥发中心附近的表面张力增大 (２．１中液体表面张力随温度升高而降低 )。这样 ,挥发中心四周的涂料有比中心处更高的表面张力 ,形成从中心向外的拉力 (见图３…     

高温陶瓷材料延迟断裂寿命预测：Knoop压痕小裂纹技术

本文对Knoop压痕小裂纹技术在陶瓷材料寿命预测研究中的应用进行了简要的评述,并举出具体的寿命预测实例说明了这一技术的实用性。     

电控LPG点燃式发动机冷起动过程瞬态NO排放特性研究

使用瞬态NO气体分析仪,结合其它发动机参数,研究缸内燃烧过程.试验结果表明NO排放可以成为判断缸内燃烧的新依据.冷起动过程中瞬态NO排放主要集中在初始的几个循环中,而发动机转速稳定后,后续循环瞬态NO排放逐渐降低.冷起动过程中,混合气浓度保持不变时,瞬态NO排放随点火角度的提前而增加.     

Microstructure tailoring of YSZ/Ni-YSZ dual-layer hollow fibers for micro-tubular solid oxide fuel cell application

YSZ/NiO-YSZ dual-layer hollow fibers with a thin YSZ top layer integrated on a porous NiO-YSZ (60:40 in weight) support, have been developed by one step method via a co-spinning-sintering process. Hydrogen reduction was performed to form YSZ/Ni-YSZ micro tube as the half solid oxide fuel cells (SOFCs). The microstructure of the dual-layer hollow fibers was tailored by adding ethanol as non-solvent in the initial mixture dopes for NiO-YSZ anode spinning. LSM cathode containing 20 wt%-YSZ was deposited on the electrolyte surface by dip-coating method to fabricate micro-tubular SOFCs. Experimental results indicate that the dual-layer hollow fibers from the anode dopes containing 15–20 wt% of ethanol possess the desired microstructure with optimized properties, such as the bending strength of 180 MPa, the porosity of 38–35% and the conductivity of 3000 S cm⁻¹ at room temperature. The micro-tubular SOFCs fabricated from such hollow fibers show a maximum power density up to 485 mW cm⁻² at 850 °C with 20 mL min⁻¹ of H₂ as fuel and 30 mL min⁻¹ air as oxidant, respectively.