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991.
合成了新型纳米银-磷酸锆复合材料并用其修饰玻碳电极,用循环伏安法对修饰电极进行电化学研究.结果表明,此复合膜保持了银的纳米尺寸的微粒性质和磷酸锆对碱性染料的电位调制能力.复合膜中的纳米银提高了磷酸锆对中性红的吸附能力,增强了中性红的氧化还原反应活性.复合膜修饰电极表现出更灵敏的电化学响应.复合膜比单纯的磷酸锆膜表现出更好的机械强度,用其制备的修饰电极表现出更好的稳定性. 相似文献
992.
993.
A. V. Khasin 《Reaction Kinetics and Catalysis Letters》1998,64(2):289-294
Kinetics of the reaction of ethylene with oxygen adsorbed on a silver film was studied by a static method at 333 K, initial
surface coverage with oxygen close to 0.8 and initial ethylene pressures of 1.1 and 4.4 Pa. The ethylene oxide selectivity
was found to increase with increasing ethylene pressure. 相似文献
994.
Reference values of the activity coefficient of hydrochloric acid at intervals of 5°C from 0 to 60°C are proposed. With their use, interlaboratory differences among silver—silver chloride electrodes can be eliminated. 相似文献
995.
采用火焰原子吸收光谱法直接测定铅精矿中高含量的银,其程序是将样品于700℃灼烧30min,以盐酸溶解后配制成溶液,用空气-乙炔火焰光度法测定样品中银的含量。该法简便、快速,结果准确。 相似文献
996.
The cation and anion transference numbers of aqueous silber perchlorate at 25°C have been determined by the direct moving
boundary method from 0.01 to 0.2 M. The cation constituent transference numbers rise in a monotone fashion with increasing
concentration contrary to the expectations, of the limiting Debye-Hückel-Onsager theory. The results can be fitted by the
revised 1963 Fuoss-Onsager theory only by the assumption of unrealistically large distances of closest approach. The behavior
of aqueous silver perchlorate closely parallels that of aqueous silver nitrate and suggests that some property of the silver
ion is responsible.
To whom correspondence should be addressed. 相似文献
997.
Noble metal nanocolloids are prepared from their precursors by in situ reduction of a silk fibroin solution at room temperature without any reducing agent. The mechanism, the effects of pH and
the molar ratio of the reactants on the reduction reaction are studied by UV-Vis spectroscopy. The structure of the colloids
is characterized by FT-IR, TEM and AFM. According to the TEM images, the gold-silk fibroin colloid is a nanostructured bioconjugate
with novel core-shell, while the silver-silk fibroin colloid tends to be congregated as clusters having more than ten nanoparticles
of silver-silk fibroin. The gold colloid is highly dispersed and stable while the silver colloid is less dispersed and stable
than the gold colloid. 相似文献
998.
丙烯气相一步氧化制环氧丙烷用Ag-Mo催化剂的研究 总被引:2,自引:0,他引:2
用浸渍法和溶胶-凝胶法制备了一系列以银及氧化钼为活性组分,负载于不同载体上的催化剂.在以分子氧为氧化剂,且原料气中不添加任何抑制剂的情况下,采用微反-色谱联合装置考察了催化剂对丙烯气相一步氧化制环氧丙烷的催化性能.结果表明,载体和助剂对催化剂上丙烯环氧化性能产生明显的影响.以TiO2-ZrO2为载体,CsNO3-NaCl为助剂的Ag-MoO3催化剂具有较好的催化性能,在400℃下,氧的转化率和环氧丙烷的选择性可分别达到11.3%和34.8%;在450℃下,氧的转化率和环氧丙烷的选择性可分别提高到33.0%和35.3%.采用溶胶-凝胶法制备的MoO3/SiO2催化剂对丙烯气相一步环氧化反应也具有一定的催化活性. 相似文献
999.
Grishina E. P. Udalova A. M. Rumyantsev E. M. 《Russian Journal of Electrochemistry》2003,39(8):903-906
Anodic oxidation of Ag–Cu and Ag–Pd alloys in concentrated sulfuric acid solutions is studied by cyclic voltammetry. Influence of electronegative (Cu) and electropositive (Pd) constituents on the rate and mechanism of the silver electrooxidation in non-steady-state conditions is revealed. The maximum silver oxidation current increases with the copper content due to a decreased H2SO4 concentration in the near-electrode layer and increased solubility of passivating phase Ag2SO4. The mechanism of ionization of palladium-doped silver is complicated by two electrochemical reactions involving the formation of Ag2SO4 and Ag+
solv. 相似文献
1000.
A. M. Zahra C. Y. Zahra M. Ganteaume S. Rossignol B. Tanguy J. J. Videau J. Portier 《Journal of Thermal Analysis and Calorimetry》1992,38(4):749-760
The glass forming ranges in the TeO2-AgO0.5 and TeO2-AgO0.5-AgI systems have been assessed for two cooling rates; results based on heat capacity and electrical conductivity measurements as well as derived from infrared spectroscopy are presented. The ternary glasses are excellent conductors due to the presence of Ag+ ions mainly supplied by AgI. The decrease in C
P with increasing AgI-content suggests the presence of AgI microdomains which are finely distributed and do not contribute to the configurational heat capacity change. Fast motion of Ag+ ions (low activation energy) occurs in the glassy matrix which shows slow structural relaxation (high activation barrier).This research is performed within the frame of a P.I.R.M.A.T. action of the CNRS. 相似文献