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991.
Tin dioxide nanoparticles of 5 nm in size were prepared on NaY zeolite external surface by impregnation of SnCl2 solution and subsequent calcination at 623 K. A SnO2-NaY based chemical sensor for detecting H2 was demonstrated. 相似文献
992.
A novel organic/inorganic compound [Hbenzimi]4[(benzimi)2Mo8O26] · 2H2O (1) has been prepared hydrothermally and characterized by elemental analyses, i.r., x.p.s., t.g. and single crystal X-ray diffraction.
The single crystal X-ray diffraction analysis reveals that compound (1) consists of the [Mo8O26]4− cluster as the structural motif covalently linked by benzimidazole molecules and protonated benzimidazole molecules as charge
compensation cations. It is interesting that the benzimidazole molecules were synthesized from 1,2-phenylenediamine and oxalic
acid. The [Mo8O26]4− polyoxoanions and organic ligands in compound (1) interact with each other via extensive hydrogen bonds to form a three-dimensional supramolecular framework. 相似文献
993.
LBL分子沉积法制备葡萄糖氧化酶电极 总被引:1,自引:0,他引:1
采用以静电力为主的逐层分子交替沉积技术制备葡萄糖氧化酶(GOD)电极.通过带有正电荷的聚二甲基二烯丙基铵盐酸盐(PDDA)和带有负电荷的GOD交替沉积在修饰有3-巯基-1-丙基磺酸钠(MPS)的金电极表面.以甲酸二茂铁为电子媒介体,用循环伏安法检测GOD电极对葡萄糖的响应.结果表明,当GOD电极组装层数小于4时,电流响应随着层数的增加而增大,超过4层时电流响应减小.其中4层GOD修饰电极的线性范围为0.55~6.63 mmol•L-1,当pH为7.0时,响应最大.同时电极的检测重现性能良好,相对标准偏差为2.4%. 相似文献
994.
Li Yan Liang Shao Ping Ren Yi Quan Zheng Man Geng Lu Guangzhou Institute of Chemistry Chinese Academy of Sciences Guangzhou China Key Laboratory of Polymer Materials for Electronics Guangdong China Graduate School of the Chinese Academy of Sciences Beijing China 《中国化学快报》2007,18(2):225-228
A series of novel liquid crystalline epoxides with lateral substituents were cured with anhydrides and the cure kinetics was investigated by non-isothermal DSC technique. The results showed that the lengths of lateral substituents have great effect on the value of Ea. The curing reaction became less active, when the liquid crystalline epoxides have long lateral substituents and were controlled by diffusion at the late stage of cure. A nematic structure was observed by POM and XRD. 相似文献
995.
Yu P Lin Y Xiang L Su L Zhang J Mao L 《Langmuir : the ACS journal of surfaces and colloids》2005,21(20):9000-9006
This letter describes the formation and possible electrochemical applications of molecular films of water-miscible imidazolium-based ionic liquids (ILs) on glassy carbon (GC) electrodes. X-ray photoelectron spectroscopy (XPS) and electrochemical results indicate that the water-miscible ILs used in this study can interact with the GC electrode and form molecular films on the electrode surface. The formed molecular films are found to possess striking electrochemical properties such as electrocatalysis toward ascorbic acid (AA) and the capability to facilitate direct electron transfer of horseradish peroxidase (HRP). This demonstration would pave the way for new electrochemical applications of water-miscible ILs and is envisaged to be useful for the investigation of the electrochemical properties of water-miscible ILs in aqueous media provided the same counteranion is used as the supporting electrolyte. 相似文献
996.
997.
998.
用CNDO/2(s,p,d)方法研究了类立方烷系列Fe-S簇合物[Fe_4S_4Cl_4(?)(S_2CNEt_2)_n]~(2-)(n=0,1,2,4)的电子结构。得出[S_2CN(Et)_2]-螯合配位Fe_4S_4~(2+)簇合物中存在两类不同价态铁原子的结论;骨架Fe_4S_4~(2+)中μ_3-S电子是非定域化的,同Mssbauer谱测定结果一致。讨论了簇合物Fe—Fe之间的成键作用、螫合配体的作用和氧化还原性质。 相似文献
999.
1000.
G. S. Chen K.-W. Schramm C. Klimm Y. Xu Y. Y. Zhang A. Kettrup 《Analytical and bioanalytical chemistry》1997,359(3):280-284
Sources and distribution of polycyclic aromatic hydrocarbons (PAH) in the Ya-Er Lake area (Hubei, China) sediment cores of 3 ponds in the shallow Ya-Er Lake were investigated for 16 PAH. Analytical procedure included extraction by ultrasonication, clean-up by gel-permeation and quantification by HPLC with fluorescence detection. The total PAH amount in sediment samples of the Ya-Er Lake ranged from 68 to 2242 μg/kg. Concentrations decreased from pond 1 to pond 3 and from upper to lower sediment layers. In addition a soil sample from Ya-Er Lake area showed a total PAH amount of 58 μg/kg. The PAH pattern in lower sediment layers were similar to that of the soil sample which indicates an atmospheric deposition into the sediments prior to 1970 only. The PAH profile of upper sediment samples, which differs completely from that of lower layers, may be explained by a gradually increasing input of mixed combustion and raw fuel sources since 1970. Therefore the origin of increased PAH contamination in Ya-Er Lake during the last 3 decades has been probably an industrial waste effluent in pond 1. 相似文献