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81.
Tinghua Wu Mingqiao Zhu Zhenjiang Niu Yijun Zhong Yan Guan Ya Liu Qiangu Yan Zelin Li Huilin WanZhejiang Normal University Institute of Physical Chemistry Jinhua ChinaZhejiang University Department of Chemical Engineering Hangzhou ChinaXiamen University Department of Chemistry Xiamen China 《天然气化学杂志》2002,(Z2)
The catalytic properties of several supported metal catalysts on different carriers were studied in the partial oxidation of methane (POM) to syngas. In our experiment, supported noble metal catalysts exhibited better performance than the other supported transition metal catalysts. The catalyst performances were significantly influenced by the d-electron configuration of the active metal components and the dispersion of active metal components on the support. A catalyst with a moderate number of unpaired electrons in the d-orbital of the active metal support without obvious acidity or redox activity (e.g. MgO) was suitable for POM performance. The Rh/SiO2 catalyst was the best in the POM reaction, among those investigated. Reaction conditions apparently also affected the POM performance of the catalyst. The conversion of methane and the selectivity for CO increased with the reaction temperature, and a high CH4/O2 ratio was not beneficial for POM performance. 相似文献
82.
新式夹心型光透薄层光谱电化学电解池 总被引:1,自引:0,他引:1
本文设计了一种新式夹心型光透薄层紫外-可见光谱电化学池。该池采用铂网工作电极,两侧平行放置铂片为对极置于同一石英窗口夹层中,同时以聚四氟乙烯隔离膜作为边际限制器,结合池内小孔道设置内参比点进行精确的电位控制,具有理想的光谱电化学响应。利用循环伏安、循环电位-吸收、恒电位现场光谱、双电位跃-计时电量、双电位跃-计时吸收等技术,对铁氰化钾在氯化钾溶液中的行为进行了表征。 相似文献
83.
POROUS MEMBRANE TEMPLATED SYNTHESIS OF POLYMER PILLARED LAYER 总被引:5,自引:0,他引:5
The anodic porous alumina membranes with a definite pore diameter and aspect ratio were used as templates tosynthesize polymer pillared layer structures. The pillared polymer was produced in the template membrane pores, and thelayer on the template surfaces. Rigid cured epoxy resin, polystyrene and soft hydrogel were chosen to confirm themethodology. The pillars were in the form of either tubes or fibers, which were controlled by the alumina membrane pore surface wettability. The structural features were confirmed by scanning electron microscopy results. 相似文献
84.
Xuejun Cui Shuangling Zhong Haitao Zhang Qiang Gu Junfeng Li Hongyan Wang 《先进技术聚合物》2007,18(7):544-548
Polytetrafluoroethylene (PTFE)‐polyacrylate core–shell nanoparticles were produced by using PTFE micropowder and acrylate via seeded emulsion polymerization in the presence of fluorosurfactant. The properties of emulsion under various polymerization conditions were investigated and optimized. The chemical composition of the PTFE‐polyacrylate nanoparticles was characterized by Fourier‐transform infrared spectrometry (FTIR). The particle size and core–shell structure of the resulting PTFE‐polyacrylate nanoparticles were confirmed by transmission electron microscopy (TEM). Wettability of the PTFE‐polyacrylate core–shell particles was higher than the pristine PTFE. The formation of this kind of PTFE‐polyacrylate core–shell nanoparticles could improve the compatibility of PTFE with other materials because PTFE is covered by polyacrylate shell, which make them promising in various fields. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
85.
Yun Gong Changwen Hu Hui Li Wanlong Pan Xueli Niu Zhifa Pu 《Journal of Molecular Structure》2005,740(1-3):153-158
Two nickel (imidazole) complexes, Ni(im)6Cl2·4H2O (1) and Ni(im)6(NO3)2 (2) (im=imidazole) have been synthesized and characterized by elemental analysis, IR, UV, TG and single crystal X-ray diffraction. 1 crystallizes in the triclinic space group P-1 with a=8.800(6) Å, b=9.081(6) Å, c=10.565(7) Å, =75.058(9)°, β=83.143(8)°, γ=61.722(8)°, V=718.3(8) Å3, Z=1 and R1 (wR2)=0.0469 (0.1497). 2 crystallizes in the trigonal space group R-3 with a=12.370(6) Å, b=12.370(6) Å, c=14.782(14) Å, =90.00°, β=90.00°, γ=120.00°, V=1959(2) Å3, Z=3 and R1 (wR2)=0.0358 (0.0955). 1 and 2 exhibit different supramolecular network due to their different counter anions and different hydrogen bonding connection. In compound 1, [Ni(im)6]2+ cation and counter anions Cl− alternatively array in an ABAB fashion via N–HCl hydrogen bonding. In compound 2, the plane of each NO32− is almost parallel and each NO32− connect three different [Ni(im)6]2+ cations via N–HO hydrogen bonding. 相似文献
86.
文中通过对变频控制直接膨胀式太阳能热泵的数值模拟,指出PV/T- SAHP系统实现变频控制从而解决太阳能热泵集热器面积与压缩机的容量不匹配的关键问题是找到系统集热/蒸发器的MSS线.为变工况下太阳能热泵系统的研究提供参考. 相似文献
87.
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89.
Tunable and Specific Formation of C@NiCoP Peapods with Enhanced HER Activity and Lithium Storage Performance
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Yuanjuan Bai Dr. Huijuan Zhang Li Liu Haitao Xu Prof. Dr. Yu Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(3):1021-1029
The superior properties of nanomaterials with a special structure can provide prospects for highly efficient water splitting and lithium storage. Herein, we fabricated a series of peapodlike C@Ni2?xCoxP (x≤1) nanocomposites by an anion‐exchange pathway. The experimental results indicated that the HER activity of C@Ni2?xCoxP catalyst is strongly related to the Co/Ni ratio, and the C@NiCoP got the highest HER activity with low onset potential of ~45 mV, small Tafel slope of ~43 mV dec?1, large exchange current density of 0.21 mA cm?2, and high long‐term durability (60 h) in 0.5 m H2SO4 solutions. Equally importantly, as an anode electrode for lithium batteries, this peapodlike C@NiCoP nanocomposite gives excellent charge–discharge properties (e.g., specific capacity of 670 mAh g?1 at 0.2 A g?1 after 350 cycles, and a reversible capacity of 405 mAh g?1 at a high current rate of 10 A g?1). The outstanding performance of C@NiCoP in HER and LIBs could be attributed to the synergistic effect of the rational design of peapodlike nanostructures and the introduction of Co element. 相似文献
90.
A Phosphorescent Platinum(II) Bipyridyl Supramolecular Polymer Based on Quadruple Hydrogen Bonds
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Fang‐Wei Liu Dr. Li‐Ya Niu Prof. Yong Chen Prof. Vaidhyanathan Ramamurthy Prof. Li‐Zhu Wu Prof. Chen‐Ho Tung Prof. Yu‐Zhe Chen Prof. Qing‐Zheng Yang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(50):18132-18139
A platinum(II) bipyridyl complex bearing bis‐ureidopyrimidinone (Pt‐bisUPy) has been designed and its self‐assembling behavior has been thoroughly investigated by 1H NMR, DOSY NMR, Ubbelohde viscometry analysis, UV/Vis, and emission spectroscopies. Pt‐bisUPy underwent concentration‐dependent ring‐chain polymerization in apolar solvents. Hydrogen‐bonding interactions play an important role during the formation of the supramolecular polymers. Hydrogen‐bonded supramolecular polymers were transformed to nanoparticles in water through the miniemulsion method. These nanoparticles showed strong π–π excimeric emission. Metal‐metal‐to‐ligand charge transfer (MMLCT) from Pt–Pt interactions was not significant in the emission spectrum. The phosphorescence of the nanoparticle persisted even under aerobic conditions. The triplet state of these phosphorescent nanomaterials were long‐lived and possessed moderate emission quantum yields. Furthermore, the low toxicity of these materials promises a place for them in in vitro and in vivo bioimaging. 相似文献