聚电解质──壳聚糖浓溶液流变学性质研究：浓度、温度、溶剂pH值和外加盐对粘度及流动性的影响

本工作用日本岩本ＲＰＸ－７０５多功能流变仪测定了在不同浓度、温度、溶剂ｐＨ值和外加盐浓度对壳聚糖在甲酸水溶液中其浓溶液粘度η随剪切速率γ的变化关系．讨论了浓度、温度等对溶液粘度、流动活化能Ｅ_γ和流动指数ｎ的影响．发现溶剂ｐＨ值减小或溶液中外加盐浓度增加，溶液粘度变小，ｎ增大，表明非牛顿流动性减弱，并且进一步讨论了零剪切粘度η_０和外加盐浓度Ｃ_ｓ的依赖关系．     

CRYSTAL AND MOLECULAR STRUCTURE OF THE COMPLEX OF METHOXYCARBONYLETHYLTIN TRICHLORIDE WITH SALICYLIDENE－M－TOLUIDINE

ＣＲＹＳＴＡＬＡＮＤＭＯＬＥＣＵＬＡＲＳＴＲＵＣＴＵＲＥＯＦＴＨＥＣＯＭＰＬＥＸＯＦＭＥＴＨＯＸＹＣＡＲＢＯＮＹＬＥＴＨＹＬＴＩＮＴＲＩＣＨＬＯＲＩＤＥＷＩＴＨＳＡＬＩＣＹＬＩＤＥＮＥ－Ｍ－ＴＯＬＵＩＤＩＮＥＦａｎｇＸｉｎＦＵ；ＸｉｕＪｕａｎＬＩ；Ｈ...     

水热法制备高纯超细CeO2-ZrO2复合氧化物

Superfine composite powders of CeO₂-ZrO₂ (CZ) and CeO₂-ZrO₂-La₂O₃ (CZL) were prepared by hydrothermal method. The effects of pH、temperature and time for hydrothermal process on the performance of the resulting powders were studied. The optimized reaction parameters were on follows: the precursor′s pH≈9.0, hydrothermal temperature of 200 ℃ holding for 2 h. Thermal stable powders with average particle size smaller than 10 nm and specific surface area of 171 m²·g^-1 were obtained. A BET specific surface area was still at 44 m²·g^-1 after calcination at 1 000 ℃ for 6 hours.     

A New Saponin Transformed from Ginsenoside Rh1 by Bacillus subtilis

A novel saponin was isolated from the transformed products of ginsenoside Rh1 by Bacillus subtilis. It‘s structure was determined to be 3-O-β-D-glucopyranosyl-6-O-β-D-glucopyranosyl-20 (S)-protopanaxatriol on the basis of the spectral data.     

Development and validation of a capillary electrophoresis method for the determination of phenothiazines in human urine in the low nanogram per milliliter concentration range using field-amplified sample injection

A capillary zone electrophoresis (CZE) method with ultraviolet-visible detection has been established and validated for the determination of five phenothiazines: thiazinamium methylsulfate, promazine hydrochloride, chlorpromazine hydrochloride, thioridazine hydrochloride, and promethazine hydrochloride in human urine. Optimum separation was obtained on a 64.5 cm x 75 microm bubble cell capillary using a buffer containing 150 mM tris(hydroxymethyl)aminomethane and 25% acetonitrile at pH 8.2, with temperature and voltage of 25 degrees C and 20 kV, respectively. Naphazoline hydrochloride was used as an internal standard. Field-amplified sample injection (FASI) has been applied to improve the sensitivity of the detection. Considering the influence of parameters affecting the on-line preconcentration (nature of preinjection plug, sample solvent composition, injection times, and injection voltage) and due to the significant interactions among them, in this paper we propose for the first time the application of a multivariate approach to carry out the study. The optimized conditions were as follows: preinjection plug of water for 7 s at 50 mbar, electrokinetic injection for 40 s at 6.2 kV, and 32 microm of H3PO4 in the sample solvent. Also, a solid-phase extraction (SPE) procedure is developed to obtain low detection limits and an adequate selectivity for urine samples. The combination of SPE and FASI-CZE-UV allows adequate linearities and recoveries, low detection limits (from 2 to 5 ng/mL), and satisfactory precisions (3.0-7.2% for an intermediate RSD %).     

规整链球型含C_(60)聚(丙烯酸β-羟乙酯)的合成及其在水中的自组装

Ｃ60 由于其独特的物理化学性质 ,在生命科学中引起了人们的广泛兴趣 .例如 :水溶性Ｃ60 的羧酸衍生物 ,羟基取代Ｃ60 ,Ｃ60 的氨基酸水溶性衍生的合成已有报道[1～ 3] ,并被用来研究Ｃ60 的生物化学及医学活性 .Ｔｏｋｕｙａｍａ[4 ] 等合成了酶功能化Ｃ60及与核酸连接的Ｃ60 ,研究并证明了它的细胞毒性及Ｇ 选择ＤＮＡ切割能力等生化活性 .Ｆｒｉｅｄｍａｎ[5]等合成了水溶性Ｃ60 的羧酸衍生物 ,研究了它对ＨＩＶ 1艾滋病毒的抑制作用 ,此外 ,关于不同Ｃ60含量的Ｃ60 蛋白质衍生物的合成及性质的研究也有报道[6] .Ｃ60 是一个直径为 0 71…     

Octa-membered Water Ring Chain Based on Sulfonic Group in Ni（Ⅱ） Complex with 2-[（E）-（2-Oxidophenyl）methyleneamino] Ethanesulfonato and 2,2＇-Bipyridinyl

The title compound, [Ni（tssb）（2,2-bipy）2].5（H2O） 1 （tssbH2 =2-[（E）-（2-oxido- phenyl）methyleneamino]ethanesulfonato, 2,2-bipy = 2,2＇-bipyridinyl）, belongs to orthorhombic, space group Pbcn with a = 20.3983（18）, b = 17.6929（15）, c = 17.0897（15） nm, V= 6167.8（9） nm^3, Mr= 688.38, Z = 8, De = 1.481 g.cm^-3, F（000） = 2880,μ = 0.758 mm-1 and S =1.099. Each NiIr atom is six-coordinated by one N and one O atoms from one tssb^2- anion and four N atoms from two 2,2-bipy ligands to give a distorted octahedral geometry. Noticeably, there exists a rare octa-mem- bered water ring which presents a 1D chain by sulfonic group.     

二维配位聚合物[Zn(PDC)(phen)]n的合成、晶体结构及荧光性质

合成了锌(II)与3,4-吡啶二羧酸和1,10-邻菲啰啉形成的配位聚合物[Zn(PDC)(phen)]_n (1) (H₂PDC＝3,4-吡啶二羧酸, phen＝1,10-邻菲啰啉), 对其进行了元素分析、红外光谱和X射线单晶衍射表征, 测定了晶体结构. 该聚合物属单斜晶系, P2(1)/n空间群, a＝0.77136 nm, b＝1.9757(4) nm, c＝1.0680(2) nm, β＝95.36(3)°, V＝1.6205(6) nm³, Z＝4, D_c＝1.683 Mg/m³, M_r＝410.68, F(000)＝832, μ＝1.55 mm^－1, 最终偏离因子R₁＝0.0608, wR₂＝0.0967. 该化合物中Zn原子与来自两个PDC的三个羧基氧原子, 另外一个PDC的吡啶氮原子, 以及phen的两个氮原子配位, 形成的ZnN₃O₃八面体通过PDC桥联形成二维层状网络结构. 此外还研究了该聚合物的热性质和荧光性质.     

A New Reaction-controlled Phase-transfer Catalyst System

A new reaction-controlled phase-transfer catalyst system was designed and synthesized.In this system, heteropolytungstate [C7H7N(CH3)3]9PW9O34 was used for catalytic epoxidation of cyclohexene with H2O2 as the oxidant. The conversion of H2O2 was 100% and the yield of cyclohexene oxide was 87.1% based on cyclohexene. Infrared spectra showed that both fresh catalyst and the recovered catalyst do have completely same absorption peak, indicating the structure of catalyst is very stability and can be recycled.     

Synthesis of 2,3,8,9-tetramethoxy-11-phenyl-5,6-dihydrodibenz[2,3;7,8]indolizine

2,3,8,9-Tetramethoxy-11-phenyldibenz[2,3;7,8]indolizine was obtainedinhighyieldfrom (6,7-dimethoxyisoquinolin-1-yl)-(3,4-dimethylphenyl)phenylcarbinol by cyclization in the presence of formic acid. The behavior of (6,7-dimethoxyisoquinolin-1-yl)-(3,4-dimethoxyphenyl)methylcarbinol and (6,7-dimethoxyisoquinolin-1-yl-(3,4-dimethoxyphenyl)carbinol was studied under these same conditions. 2,3,7,8-Tetramethoxy-11-phenyl-5,6-dihydrodibenz[2,3;7,8]indolizine was obtained by hydrogenation on rhenium heptasulfide.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1233–1238, September, 1993.