MnO_x对Cu/γ-Al_2O_3催化剂结构及性能的调变作用(英文)

运用ＸＲＤ、ＴＰＲ、Ｈ２－ＴＰＤ等表征手段考察了Ｃｕ－Ｍｎ催化剂的物相结构、氢气的还原性能及Ｈ２的吸附性能;在高压微反色谱系统中进行了ＣＯ加氢合成二甲醚的研究并和表征结果相关联。评价结果表明,Ｃｕ－Ｍｎ双组分催化剂对一氧化碳具有很高的活性及二甲醇的选择性; ＸＲＤ测定结果表明, Ｍｎ的存在使得ＣｕＯ的分散度提高：ＴＰＲ结果表明,锰的存在阻碍了ＣｕＯ的还原,ＣｕＯ存在能够促进ＭｎＯｘ的还原,双组分催化剂的还原并不是单组分催化剂的简单叠加,说明在催化剂的制备过程中ＣｕＯ和ＭｎＯｘ之间发生了一定的相互作用。Ｈ２的脱附实验表明,Ｍｎ的添加增强了催化剂对Ｈ２的吸附能力。     

Organic peroxide production in the Cl2-ethane-air photoreaction system

HPLC along with FT-IR technique was used to study the formation of organic peroxides in the Cl₂-ethane-air photoreaction system. Ethyl hydroperoxide (CH₃CH₂₁OOH, EHP) and peroxyacetic acid ( CH₃C(O)OOH, PAA) were conformed to be the peroxide product in the reaction system. In addition, methyl hydroperoxide (CH₃OOH, hydroxymethyl hydroperoxide (HOCH₂OOH, HMHP) and two unidentified organic peroxides were detected for the first time. EHP and were the dominant peroxide products. The identification of HMHP showed that Criegee biradical CH₂OO may be formed as an intermediate in the oxidation of ethane. Simulation results showed that photooxidation of ethane may make substantial contribution to source of organic peroxides in the atmosphere.     

Formation and Characterization of Reversed Micelles Composed of Phospholipids and Fatty Acids

The formation of reversed micellar systems composed of phosphatidylcholine (PC) and fatty acid was newly demonstrated by a significant increase in water content in the organic ethyl oleate phase when the micelles were prepared by the contact method. The solubilized water concentration in the reversed micellar organic phase reached 3 wt%. The new systems are expected to be used as highly biocompatible reversed micellar systems. The structure of the reversed micelles composed of PC and oleic acid was characterized by determining the water concentration and by small-angle X-ray scattering analysis. The reversed micelles composed of PC and oleic acid formed in ethyl oleate were spherical. The radius of gyration was between 30 and 50 Å. The size of the reversed micelles decreased with an increase in the oleic acid concentration and was independent of the PC concentration. Experimental results indicated that the structure of the reversed micellar system was determined by the oleic acid concentration. An increase in the PC concentration caused an increase in the number of reversed micelles of the same size. These reversed micellar systems are expected to be used as solubilization media in pharmaceutical and food industries because they are not toxic.     

N，N＇-双(3-羧基水杨醛叉缩胺乙基)草酰胺均双核铜(Ⅱ)，镍(Ⅱ)配合物合成和性能研究

The homobinuclear complexes of Cu (Ⅱ) and Ni (Ⅱ) with N, N＇-bis(3-Carboxyl salicyl aminal ethylene) oxalamide were synthesized, and characterized by elemental analysis, IR spectra, Uv-visible spectra, conductometry, thermogravimetry, and magnetic susceptibility measurement, which indicated the complexes own an oxalic amide bridge-linking structure. Room temperature magnetic moment data show that there are antiferromagnetic spin coupling through oxalic amide conjugated double bond, In DMF, the redox half wave potential of Cu (Ⅱ) binuclear complexes have been measured by cyclic voltammetry, which proves that the Cu (Ⅱ) complex has two redox waves.     

Enantioselective Allylic Oxidation of Olefins Using Chiral Quinolinyl‐oxazoline Copper Complex Catalysts

Copper complexes of chiral quinolinyl‐oxazoline have been studied as the catalysts for enantioselective allylic oxidation of cycloalkenes with tert‐butyl perbenzoate. Using 5 mol% of these chiral catalysts, optical active allylic benzoates were obtained in moderate enantiomeric excesses. CuOTf prepared in situ, CuClO₄ and CuPF₆ were found to be good precatalysts in acetone.     

Molecular Design of Calixarene 5. Syntheses and Cation Selectivities of Novel Schiff's Base p‐tert‐Butylcalix[4]arenes

Five novel Schiff's bases p‐tert‐butylcalix[4]arenes have been synthesized in high yields by the reaction of 1,3‐distally disubstituted p‐tert‐butylcalix[4]arene amine (1) with the corresponding aromatic aldehydes, and their cation binding abilities and selectivities with alkali and heavy metal ions have been evaluated by solvent extraction of aqueous metal picrates to show the highest Ag⁺ extractability for Schiff's base p‐tert‐butylcalix[4]arene (6) and the best Na⁺/Li⁺ and Ag⁺/Ti⁺ selectivities for Schiff's base p‐tert‐butylcalix[4]arene (4 and 2) over any other calix[4]arene derivatives, respectively.     

A Novel Conversion of 2, 4‐Diaryl‐2, 3‐dihydro‐1 H‐1, 5‐benzodiazepines into 2, 4‐Diaryl‐3 H‐1, 5‐benzodiazepines

A novel conversion of 2, 4‐diaryl‐2, 3‐dihydro‐1 H‐1, 5‐benzodiazepins into 2, 4‐diaryl‐3 H‐1, 5‐benzodiazepines by the reaction with m‐chloroperbenzoic acid (MCPBA) was reported.     

Studies on chemistry and immuno‐ modulating mechanism of a glycoconjugate from Lycium barbarum L.

The detailed structure of an O‐glycan derived from the fruit of Lycium barbarum L. was elucidated based on glycosidic linkage analysis, complete and partial acid hydrolysis, ¹H‐NMR and ¹³C NMR spectroscopy. According to the experiments, the carbohydrate was in the form of polysacchride (arabinogalactan) chains with highly branched 3, 4‐galactans and terminal arabinofuranosyl substituents. The immuno‐modulating mechanism of glycoconjugate and its glycan were investigated using tritium thymidine incorporation assay, flow cytometry assay and electrophoretical mobility shift assay (EMSA). The results suggested that the immunoactive components of the fruit of Lycium barbarum L. could enhance the splenocyte proliferation in normal mice and the effects of glycan chain were stronger than those of glycoconjugate. The target cell was most likely to be B‐lymphocyte, on which existed receptor binding site acting with the glycan. In addition, the immuno‐stimulatory effect of glycoconjugate (LbGp4) and its glycan (LbGp4‐OL) was associated with activating the expression of nuclear factor KB (NF‐KB) and activator protein 1 (AP‐1).     

Study on intercalation and exfoliation behavior of organoclays in epoxy resin

Intercalation and exfoliation behavior of organoclays in epoxy resin has been studied through XRD and DSC. It was found that the organoclays were easily intercalated by epoxy oligomer to form a stable epoxy/clay intercalated hybrid. Under appropriate conditions the clays were able to be further exfoliated as the epoxy resin was cured; thus, a nanocomposite was obtained. It was also found that the exfoliating ability of the organoclays was basically determined by the nature of the clays and the curing agent used. The exfoliation mechanism is discussed in this paper. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 39: 115–120, 2001