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101.
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
102.
Density functional theory calculations have been carried out on the CO/H2 coadsorption on the (001), (110), and (100) surfaces of Fe5C2 for the understanding of the Fischer-Tropsch synthesis (FTS) mechanism. The stable surface species changes with the variation of the H2 and CO coverage. Along with dissociated hydrogen and adsorbed CO in 2-, 3-, and 4-fold configurations, methylidyne (C(s)H) (C(s), surface carbon), ketenylidene (C(s)CO), ketenyl (C(s)HCO), ketene (C(s)H2CO), and carbon suboxide (C(s)C2O2) are computed as thermodynamically stable surface species on Fe5C2(001) and Fe5C2(110) containing both surface iron and carbon atoms. These surface carbon species can be considered as the preliminary stages for FTS. On Fe5C2(100) with only iron atoms on the surface layer, the stable surface species is dissociated hydrogen and CO with top and 2-fold configurations. The bonding nature of these adsorbed carbon species has been analyzed. 相似文献
103.
Guoyi Bai Chenfang Zhang Yuecheng Zhang Haijun Yu Fei He Huisen Ning Ligong Chen 《Reaction Kinetics and Catalysis Letters》2007,90(2):373-380
The racemization of R-(-)-2-amino-1-butanol in a reaction using Co/γ-Al2O3 catalysts and catalysts modified by Mg or Ca was investigated in this paper. Complete racemization was achieved with a yield
of over 83% at using the Mg modified Co/γ-Al2O3 catalyst under optimized reaction conditions of 170°C and 2.5 MPa of H2. The catalysts were thoroughly characterized by XRD, XPS, TPR, SEM and TEM. The addition of Mg and Ca may be advantageous
for dispersing and stabilizing the active species of the Co/γ-Al2O3 catalyst, protecting from sintering, significantly improving its catalytic activity and stability. 相似文献
104.
Organo-tricyanoborates as tectons: illustrative coordination polymers based on copper(I) derivatives
The first systematic study on the use of tricyanoborates as ligands is presented. The tricyanoborates [RB(CN)3]- (R = oct and Ph) can be prepared by direct cyanation of RBCl2 precursors as well as by thermolysis of the corresponding isocyanides [RB(NC)3]-. The first organo-cyanogallates [RGa(CN)3]- (R = Bu, C6H2-2,4,6-Me3) were prepared from the corresponding dichloride, the structure of Et4N[mesGa(CN3] being confirmed crystallographically. The reaction of equimolar [RB(CN)3]- (R = oct, Ph) and [Cu(MeCN)4]+ afforded two-dimensional polymers [RB(CN)3Cu(NCMe)]. The sheets arise via conjoined hexagonal B3Cu3(CN)6 rings with chair conformations. The reaction of excess [PhB(CN)3]- and [Cu(MeCN)4]+ gives the polymer [K(18-crown-6)]{Cu[PhB(CN)3]2}. Treatment of [PhB(CN)3]- with [Cu(PCy3)2(NCMe)x]PF6 gave the one-dimensional polymer [PhB(CN)3Cu(PCy3)2], wherein two of the three BCN substituents are coordinated. 相似文献
105.
Jinglong Zhang Huasheng Xu Haijun Chen Mazakazu Anpo 《Research on Chemical Intermediates》2003,29(7-9):839-848
Titanium dioxide (TiO2) nanoparticles of both anatase and rutile phases were synthesized by hydrothermal treatment of microemulsions, and their photocatalytic activity for the degradation of X-GL dye was investigated. The only difference between the two methods used was that different acids were added to the microemulsions to make a direct comparison of the photocatalytic activity of the polymorphs possible. UV — Vis reflectance and XRD spectroscopic investigations of these titanium dioxides indicated that a rutile structure could be formed (PR) when hydrochloric acid was used, and anatase formed (PA) when nitric acid was used. The activity of the two polymorphs and P-25 for the photocatalytic degradation of dye in water was also examined. It was found that P-25 consisting of anatase and rutile has the highest activity, and PR consisting of rutile has the lowest. Photodegradation of X-GL in the presence of these different TiO2 particles under air-equilibrated controlled conditions led to the formation of hydrogen peroxide. The formation rate of H2O2 depended on the difference in crystalloid phase. These results indicate that the observed differences in the photocatalytic activity for the three TiO2 photocatalysts are directly related to the formation rate of H2O2. 相似文献
106.
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
107.
用数字化模型代替三维实体模型,将内圆磨床主要大件的BP神经网络模型放入数据库信息管理系统,应用较简单的使用方法实现了零件结构的再修改、灵敏度分析及优化.根据所提出的方法,通过从数据库信息管理系统中调用桥板的数据文件,对其进行结构参数修改、灵敏度分析及以第1阶扭转频率最高为目标的设计变量自动搜索寻优计算,结果表明将BP神经网络模型与数据库信息管理系统结合是实现零件快速反应设计的有效途径. 相似文献
108.
裂足轮虫还是裂足臂尾轮虫 总被引:3,自引:0,他引:3
通过分析比较了裂足轮虫(Brachionus diuersicornis)、方型臂尾轮虫(B.quadridentatus)、壶状臂尾轮虫(B.urceus)、矩形臂尾轮虫(B.1eydigi)、萼花臂尾轮虫(B.calyciflorus)等5种轮虫的线粒体细胞色素氧化酶亚基I(COI)的部分序列,并结合4种海水臂尾轮虫的序列数据,用西氏晶囊轮虫(Asplanchna.sieboldi)作外群构建UPGMA树和NJ树,探讨了烈足轮虫的分类学问题,认为将裂足轮虫归属千臂尾轮虫属市为合适。 相似文献
109.
本文论述了光纤式表面粗糙度测量仪研制过程中关键问题的解决方法,对非线性特性的参数计算、零点漂移、信号噪声、不同加工表面特性差异的处理都给出了完美的解决方法。该仪器以光散射理论为测量原理,用光纤为传输媒介,并用单片机8098进行计算、数据处理和测量智能控制。 相似文献
110.
Multi-ester type biscrown ether compound(I) was prepared by the reaction of 6-bromoacetacetic ester dibenzo-16-crown-5(7)
with phenyl-methyl ether-2,6-diformic acid potassium salt in anhydrous DMF at refluxed temperature, and color biscrown ether
compound(II) was prepared by the reaction of 4′-aminobenzo-15-crown-5(12) with 2,2′(O-formoyl naphthyl)ethyl ether (9) in
anhydrous ethanol at 40 C under N2. New compounds(I, II) were characterized by IR,1H NMR, MS and elemental analysis.
Supported by the National Natural Science Foundation of China
Niu Changrong: born in December, 12, 1938, Professor 相似文献