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31.
Tsai HH Chiu PJ Jheng GL Ting CC Pan YC Kao HM 《Journal of colloid and interface science》2011,359(1):86-94
Well-ordered cubic mesoporous silicas SBA-1 functionalized with sulfonic acid groups have been synthesized through in situ oxidation of mercaptopropyl groups with H(2)O(2) via co-condensation of tetraethoxysilane (TEOS) and 3-mercaptopropyltrimethoxysilane (MPTMS) templated by cetyltriethylammonium bromide (CTEABr) under strong acidic conditions. Various synthesis parameters such as the amounts of H(2)O(2) and MPTMS on the structural ordering of the resultant materials were systematically investigated. The materials thus obtained were characterized by a variety of techniques including powder X-ray diffraction (XRD), multinuclear solid-state Nuclear Magnetic Resonance (NMR) spectroscopy, (29)Si{(1)H} 2D HETCOR (heteronuclear correlation) NMR spectroscopy, thermogravimetric analysis (TGA), and nitrogen sorption measurements. By using (13)C CPMAS NMR technique, the status of the incorporated thiol groups and their transformation to sulfonic acid groups can be monitored and, as an extension, to define the optimum conditions to be used for the oxidation reaction to be quantitative. In particular, (29)Si{(1)H} 2D HETCOR NMR revealed that the protons in sulfonic acid groups are in close proximity to the silanol Q(3) species, but not close enough to form a hydrogen bond. 相似文献
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栅极增强等离子体源离子注入(GEPSII)一种新的金属管件内壁处理方法,该方法能够均匀地对金属管件内壁进行离子注入,并且能够生成二元金属化合物.在金属管件内轴向放置三块45号钢样品,利用GEPSII方法在金属管件内壁成功生长金黄色氮化钛(TiN)薄膜.结构分析显示TiN主要沿(111)和(200)晶面生长,深度分析显示膜的厚度大约二十几纳米,膜质地均匀且在基底有一定的嵌入深度.电化学腐蚀、硬度、磨擦学分析表明TiN薄膜很好地改善了45号钢的表面性能,并且表现出很高的轴向均匀性.
关键词:
等离子体源离子注入
内表面
氮化钛 相似文献
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以N-苄氧羰基-(S)-脯氨酸和5-(1-氨基烷基)四氮唑(烷基: 甲基、乙基、2-苯基乙基)为原料, 经两步反应合成了3个新颖的有机催化剂: (S)-5-脯氨酰胺基甲基四氮唑(3a), (S,S)-5-(1-脯氨酰胺基乙基)四氮唑(3b)和(S,S)-5-(1-脯氨酰胺 基-2-苯基乙基)四氮唑(3c), 并首次将其用于催化丙酮和含吸电子基芳香醛的不对称直接aldol反应. 在室温条件下, 催化剂3b表现出较好的催化活性, 产物的ee值最高可达96%. 相似文献
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A para-terphenyl derivative containing a lateral diphenylamino group and two terminal dicyanovinyl groups has been designed and synthesized. This compound displays aggregation-induced emission characteristics and thus shows intense intramolecular charge transfer fluorescence even in the condensed state, including in the aggregates formed in an aqueous solvent system consisting of greater than 99% water and in the solid state. The addition of cyanide to its aggregates in aqueous media induces a large blue shift in fluorescence, enabling ratiometric fluorescence sensing of cyanide anions. In addition, its prompt fluorescence responses to cyanide anions were also observed even in the solid state. 相似文献
37.
We construct the transfer matrix for the open chain with the centrally extended SU(2|2) symmetry attached to the so called Z = 0 giant graviton brane. Using the reflection equations,unitarity property and crossing property,we show that this model is integrable. 相似文献
38.
A cold dielectric barrier discharge (DBD) plasma plume with one highly conductive liquid electrode has been developed to treat thermally sensitive materials, and its preliminary discharging characteristics have been studied. The averaged electron temperature and density is estimated to be 0.6eV and 1011/cm3, respectively. The length of plasma plume can reach 5cm with helium gas (He), and the conductivity of the outer electrode affects the plume length obviously. This plasma plume could be touched by bare hand without causing any burning or painful sensation, which may provide potential application for safe aseptic skin care. Moreover, the oxidative particles (e.g., OH, O*, 03) in the downstream oxygen (02) gas of the plume have been applied to treat the landfill leachate. The results show that the activated 02 gas can degrade the landfill leachate effectively, and the chemical oxygen demand (COD), conductivity, biochemical oxygen demand (BOD), and suspended solid (SS) can be decreased by 52%, 57%, 76% and 92%, respectively. 相似文献
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Li Yu-Fu Xia Yong-Xia Xu Dong-Peng Li Guang-Liang 《Journal of polymer science. Part A, Polymer chemistry》1981,19(12):3069-3079
The interaction of silica and oligomeric methylsiloxanes, methylsilicone oil as well as silicone gum at elevated temperature was studied. It was found that a reaction takes place between surface silanols and octamethylcyclotrasiloxane (D4) above 180°C. Part of the methylsiloxane replaces the surface silanols forming loops with the surface, while the other part is redistributed to its neighboring homologoues. The methylsiloxy surface groups thus formed can undergo further reaction with the other methylsiloxanes above 250°C. Methylsilicone oil behaves similarly. The reaction with silicone gum was demonstrated by the formation of “chemically bound rubber.” The mechanism of the reaction is discussed. 相似文献
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The Ramanujan Journal - We give an asymptotic formula for $$\sum _{1\le n_1.n_2, \ldots ,n_l\le x^{1/r}}\tau _k(n^r_1+n^r_2+\ldots +n^r_l)$$ , where $$\tau _k(n)$$ represents the k-th divisor... 相似文献