Pd-Rh型国Ⅲ排放三效催化剂的研制

对满足欧Ⅲ排放限值的Pd-Rh型三效催化剂进行研究开发,测试了新鲜催化剂的空燃比特性和起燃温度特性,并与市场上的欧Ⅲ催化剂在同等条件下老化后的性能进行了比较.对研制的催化剂进行封装总成后,按照GB18352.3-2005标准进行了常温冷起动Ⅰ型和低温冷起动IV型试验,测试结果完全能满足该标准的限值要求.     

A spectroscopic study on the 12-heteropolyacids of molybdenum and tungsten (H3PMo12−nWnO40) combined with cetylpyridinium bromide in the epoxidation of cyclopentene

The epoxidation of cyclopentene with hydrogen peroxide catalyzed by 12-heteropolyacids of molybdenum and tungsten (H₃PMo_12−nW_nO₄₀, n = 1–11), 12-tungstophosphoric acid and 12-molybdophosphoric acid combined with cetylpyridinium bromide as a phase transfer reagent was carried out in acetonitrile. Among 13 heteropolyacids investigated, catalyst of H₃PMo₆W₆O₄₀ showed the highest activity, giving a conversion of 60% and a selectivity of 95% in the epoxidation of cyclopentene. The fresh catalysts and the catalysts under reaction condition were characterized by UV–vis, FT-IR and ³¹P NMR spectroscopy, which has revealed that all of the molybdotungstophosphoric acids were degraded in the presence of hydrogen peroxide to form a considerable amount of phosphorus-containing species. The active species resulted from H₃PMo₆W₆O₄₀ are new kinds of phosphorus-containing species, which is different from {PO₄[WO(O₂)₂]₄}³⁻.     

Propane oxidation over Pd/LaFe0.8Co0.2O3 catalyst

Pd/LaFe_0.8Co_0.2O₃ was found to be more active than the Pd/Al₂O₃ catalyst in propane oxidation. Activity and the oxidation state of palladium were strongly affected by the redox ratio (S) of reactants. Higher propane conversion could be obtained under rich conditions at higher temperatures, contributing to steam reforming. The presence of excess steam would bring about inhibition and oscillation.     

Stable, reproducible nanorecording on rotaxane thin films

Stable, reversible conductance transitions and memory effects were observed in solid-state rotaxane-based Langmuir-Blodgett (LB) thin films. Taking advantage of the switching property, we have achieved reproducible nanometer-scale recording dots on rotaxane LB films via voltage application using a scanning tunneling microscope probe. The stable and easily controlled conductance switching makes the rotaxanes a hopeful candidate for nanorecording.     

酯化交联聚乙烯醇膜用于渗透气化法分离EtoH／H2O的研究

合成了一系列磷酸和二元羧酸酯化交联改性的聚乙烯醇(PVA)膜,研究了它们用于水-乙醇混合液的渗透气化分离规律。磷酸改性的PVA膜具有较大的通量,当料液浓度为50%时,通量可达1200g/m~2·hr.,分离系数α_(H_2O/EtOH)=10。丙二酸改性PVA膜在料液浓度为50%时,通量可达800g/m~2·hr.,且α_(H_2O/EtOH)=18。并作了这两种膜的通量和分离系数随料液浓度的变化曲线。草酸交联的PVA膜具有较高的分离系数,但通量很小。求出了水、乙醇及总的表现渗透活化能。     

Study of the Complexation Behavior of Calixarene with Transition Metal Cations by UV—vis and Fluorescent Spectra

A new fluorescent compound based on calix[4] arene skeleton was synthesized.Its complexation ability with transition metal ions,such as Fe^3 ,Co^2 ,Ni^2 ,Cu^2 ,Zn^2 and Ag^ ,Was investigated by UV-vis and fluorescent spectra.     

Enhanced electrodeposition of indium hexacyanoferrate thin films through improved plating solution stability

An ordinary plating solution for indium hexacyanoferrate (InHCF) thin film deposition, mainly composed of equal concentrations of In³⁺ and [Fe(CN)₆]^3–, usually forms precipitates rapidly when either concentration is higher than few millimolar. This contributes to the plating solution's instability. Moreover, electrodeposited capacities are limited accordingly. In this work, the plating solution's stability and the electrodeposition of InHCF were greatly enhanced by adding a large amount of K⁺ and/or H⁺. It was found that a 10-mM plating solution added with 1 M HCl and 1 M KCl could be stored as fresh over a one-week period, whereas an unmodified plating solution became useless within a couple of minutes. Also, such cationic additions, especially adding H⁺, increased the electrodeposited capacity ca. 18 times at least, as compared with that obtained from the unmodified plating solution. Furthermore, related enhancing mechanisms were proposed and verified. To sum up, this study offers a means for better InHCF electrodeposition and should promote the applications of InHCF films. Electronic Publication     

1β—Methyl Carbapenem中间体的合成

综述了１β－Ｍｅｔｈｙｌ Ｃａｒｂａｐｅｎｅｍ中间体的合成方法，重点强调了如何构筑１位β构型的甲基。参考文献３７篇。     

Use of Two-Dimensional Liquid Chromatography Combined with Diode-Array and Mass Spectrometric Detection for Analysis of Compounds in Flos Lonicera

Comprehensive two-dimensional liquid chromatographic separation by means of a combination of ion-exchange chromatography (IEC) and reversed-phase liquid chromatography (RPLC) has been realized and applied to the analysis of components of a traditional Chinese medicine Flos Lonicera. In the first dimension the components of a Flos Lonicera extract is separated on strong anion-exchange (SAX) column according to the charge-exchange properties of the components. In the second dimension the components are further fractionated by reversed-phase liquid chromatography (on ODS) on the basis of their hydrophobicity. The RPLC effluent is desalted and split and the components are identified on-line by use of both diode-array detection and mass spectrometry with atmospheric pressure chemical ionization (APCI–MS). In this way, the extract of Flos Lonicera can be rapidly separated, desalted, and analyzed, with determination of molecular weight. More than 58 components of an extract of Flos Lonicera were well resolved and six were tentatively identified from their UV and mass spectra.