Promoting effect of sol-gel method and pre-treatment on the activity of SnO2/Al2O3 catalyst for NO reduction by propene

SnO₂/Al₂O₃ catalyst prepared by sol-gel method showed higher activity than those prepared by impregnation method, and their activity was significantly improved by pre-treatment in the reaction gas. The increased activity is closely related to the agglomeration of SnO₂ species and the re-exposure of Al₂O₃, which was previously covered by dispersed SnO₂ species. This revised version was published online in June 2006 with corrections to the Cover Date.     

2, 2＇─(1, 4─亚乙二氧基)—二苯甲酸与钴(Ⅱ)生成的两种配合物的结构研究

硝酸钴与２，２＇－（１，４－亚乙二氧基）－二苯甲酸（Ｈ２Ｌ，图１）作用分别得到红色配合物ＣｏＬ＇和蓝色配合物ＣｏＬ″。经元素分析、红外光谱、紫外可见光谱、热分析等方法进行了表征、ＣｏＬ＇配合物的分子式为［ＣｏＬ．Ｈ２Ｏ］．３Ｈ２Ｏ，近八面体构型，羧酸根以双齿形式与Ｃｏ（Ⅱ）螯合；ＣｏＬ″配合物分子式为［ＣｏＬ″］。Ｈ２Ｏ，近四面体构型，羧酸根以单齿形与Ｃｏ（Ⅱ）配位。     

Synthesis and Crystal Structure of Glycin·3,5-Dihydroxybenzoic Acid

The title compound glycin·3,5-dihydroxybenzoic acid (GDB) has been synthesized and characterized by single-crystal X-ray analysis. It crystallizes in orthorhombic, space group Pca21 with a = 25.513(10), b = 4.668(2), c = 9.150(4)(A), Z = 4, V = 1089.8(8)(A)3, C9H13NO7, Mr = 247.20, Dc = 1.507 g/m3, μ(MoKα) = 0.132 mm-1, F(000) = 520, R1 = 0.0322 and wR2 = 0.0611 for 885 observed reflections (I > 2σ(I)). The title compound is a 1:1 molecular complex of glycin and 3,5-dihydroxybenzoic acid, which is linked by O-H…O and N-H…O hydrogen bonds to form a three-dimensional framework. Test of SHG (second harmonic generation) indicates that NLO generation of the crystal is higher than that of KDP.     

弱碱性阴离子交换树脂分离1,6—二磷酸果糖的研究

采用弱碱性阴离子交换树脂HJ-30对发酵液中1，6-二磷酸果糖的分离进行了研究。详细地研究了树脂的吸附和脱附性能。实验结果表明，HJ-30树脂对FDP的吸附量达0．28gFDP／g湿树脂，以0．05mol／LNaCl洗脱光机磷和1mol／LNaCl洗脱1，6-二磷酸果糖，产品的收率和纯度分别为92％和99．4％。     

Influence of ultrasonic field on microcystins produced by bloom-forming algae

Under the background of algae removal and growth inhibition by ultrasonic irradiation, the effects of ultrasonic irradiation on removal of Microcystis, the concentration variation of microcystins (MC) produced by Microcystis in Microcystis suspension, and sonochemical degradation of microcystins in water, were studied in the paper. The results showed that ultrasonic irradiation could efficiently inhibit the growth of Microcystis, and ultrasonic irradiation shorter than 5 min would not introduce the increase of microcystins dissolved in Microcystis suspension simultaneity. Also, microcystins dissolved in Microcystis suspension would not increase as ultrasonic power increasing. Further research showed that microcystins were effectively degraded in ultrasonic fields. After 20 min ultrasonic irradiation at 150 kHz and 30 W, the removal rate of microcystins reached 70%.     

聚乙撑二氧噻吩膜在氧化态的充电过程及电容研究

In this paper, the chronoamperometry was used to study the charging processes of polyethylenedioxythiophene (PEDOT) modified electrodes in the potential range where PEDOT was in the oxidized state. The results show that the charging behaviors of the PEDOT films are well agreed with the exhausted finite diffusion model. The dependence of the capacitance values of the films on potential and concentration of solution was also studied in this potential range.     

Simultaneous determination of sulfite, sulfate, and hydroxymethanesulfonate in atmospheric waters by ion-pair HPLC technique

A reversed-phase ion-pair HPLC with indirect photometric detection for the simultaneous determination of sulfite, sulfate, hydroxymethanesulfonate (HMS), and other inorganic anions in atmospheric water has been developed. Separations were accomplished in less than 10 min in a cetylpyridinium-coated C₁₈ column with 0.5 mM potassium hydrogen phthalate-0.015% triethanolamine-3% methanol at pH 7.9 as mobile phase. Quantitation was carried out by the peak area method, with detection limits in the pmol range. UV light absorption responses were linear over a wide concentration range from several hundred μmoles to the detection limits of each anion. The application of the method provides a rapid and efficient technique for the quantitative determination of sulfur and other inorganic species in atmospheric liquids.     

硫化物的生物氧化成手性亚砜

描述了硫化物不对称生物氧化成手性亚砜, 主要为氯过氧化物酶、环己酮单氧酶催化有机硫化物氧化成具有光学活性的亚砜的两条酶促反应途径.     

Cooperation of reducing species for NO reduction over Ag/Al2O3 under oxidizing conditions

Summary The cooperation effect of reducing species for selective reduction of NO over Ag/Al₂O₃ has been investigated in the presence of excess oxygen. When the combinations of propene or propane and ethanol or methanol were used as reducing agents, NO reduction took place over a wider temperature range, compared with a single hydrocarbon as reducing agent.     

玻璃载体表面脱氧核糖核酸的固定及其化学发光检测

用硅烷化偶联剂把ＤＮＡ直接共价固定在载玻片表面，将辣根过氧化物酶标记的探针与之进行核酸杂交，杂交后用增强的化学发光检测。方法的检出限为７５ｐｇ。研究了ＤＮＡ分子固定在玻璃载体表面的各种条件，并建立了在玻璃载体表面进行核酸杂交的体系，为研究光纤ＤＮＡ生物传感器打下了基础。