寡糖快原子轰击质谱中碱金属加合离子应用技术的研究

生命科学的研究成果^[1～3]表明,糖蛋白和糖脂中的糖基可作为细胞的识别信号,能控制细胞的分裂和分化.快原子轰击(FAB)质谱是测定寡糖的重要手段^[4,5],但目前还存在不少问题.我们在对麦芽各糖的研究中.     

V2O5电致变色薄膜的Raman光谱

近年来,通过向过渡金属氧化物薄膜注入Ｌｉ 制作可调节光透过率的电变色器件已越来越引起广泛的重视[1、2].由于Ｖ2Ｏ5薄膜的稳定性差,限制了它在实际中的应用.因此,为了获得变色效率高、稳定性和可逆性能好的Ｖ2Ｏ5薄膜,使用了多种制备方法,如磁控溅射法[3、6]、电化学沉积法[7、8]、溶胶凝胶法[9、10]、旋涂法[11、12]、真空蒸镀法[13、14]等.但是,无论那种方法都要解决Ｖ2Ｏ5本身在Ｈ2Ｏ或醇等的电解质溶液中电致变色时的溶解问题,通常采用控制薄膜的沉积温度或者退火处理来提高薄膜的电致变色性能[3、4、11].为了探明薄膜结构与电致变色…     

Laser-induced Fluorescence Excitation Spectrum of NiS in 15500-17200 cm^-1

The laser-induced fluorescence excitation spectrum of jet-cooled NiS molecule has been recorded in the energy range of 15500 17200 cm-1. Fifteen bands have been assigned as three transition progressions：[15.65]^3Ⅱ1（v′=0-4）-X^3∑0^-（v″=0）,[15.69]^3∑0^-（v′=0-4）-X^3∑0^-（v″=0）,and [15.81]^3Ⅱ1（v′=0-4）-X^3∑0^-（v″=0）.Spectroscopic constants for the three newly identified electronically excited states have been determined for the first time. In addition,the lifetimes for most observed vibronic bands have also been measured.     

Two new bromoindoles from red alga Laurencia similis

Two new bromoindole alkaloids have been isolated from the ethanolic extract of the red alga Laurencia similis.On the basis of chemical and spectroscopic methods(including 1D and 2D NMR technique),their structures have been elucidated as 2,2′,5,5′,6,6′-sixibromo -3,3′-bi-1H-indole and 3,5-dibromo-1-methylindole,respectively.     

青黛中微量元素含量测定分析

用原子吸收分光光度法测定了青黛中的7种微量元素。结果表明,青黛中含有丰富的人体必需的微量元素和极微量的有害元素镉和铅。     

Synthesis, Characterization and Crystal Structure of [Ni（S2P{O}OC6H4CH3-p）（dppv）]

O-（p-tolyl）dithiophosphato nickel complex [Ni（S2P{O}OC6HaCH3-p）（dppv）] has been synthesized by the treatment of （dppv）NiCl2 （dppv = Ph2PCH=CHPPh2） with （p-CH3C6HaO）2P{S}SH＇Et2NH in THF. The new complex was fully characterized by elemental analysis, IR, 1H NMR, 31p NMR spectroscopies and thermo-gravimetric analysis. The molecular structure of the complex was established by X-ray crystallography. The crystal crystallizes in monoclinic, space group P21/c with a = 9.2739（5）, b = 17.8803（8）, c = 20.1879（12） A, fl = 93.269（5）, V = 3342.1（3） A3, Z = 4, C33H29NiO2P3S2, Mr = 673.30, Dc = 1.338 g/cm3, F（000） = 1392 and #（MoKa） = 0.877 rnm-l. The final R = 0.0578 and wR = 0.1045 for 4138 observed reflections with 1 〉 20（/） and R = 0.1050 and wR = 0.1204 for all data. The Ni centre atom adopts a NiP2S2 square-planar geometry with two phosphorus atoms from the dppv ligand and two sulfur atoms from the O-（p-tolyl）dithiophosphate ligand. The most interesting structural feature of the title complex resides in its 1D helical chain structure constructing via intermolecular C-H＇＂O secondary interactions along the b-axis. The adjacent helical chains running in opposite directions are connected into a 1D double-stranded helical chain and further linked into a 2D supramolecular network by weak C-H.--C interaction.     

新的氨基酸受体的合成和分子识别性质研究

从双氨基甲基手性双环胍出发,经三步反应合成了由稳定的共价键桥联双环胍、氮杂冠醚和萘环的氨基酸受体1.液-液竞争萃取和^1HNMR实验表明受体对氨基酸两性离子具有较好的侧链选择性和对映选择性,能够选择性地将L-芳香族氨基酸从水相转移到二氯甲烷有机相。     

原子吸收法在有机分析中的应用（Ⅲ）：茶叶中茶多酚的测定

研究了间接测定茶叶中茶多酚的原子吸收，用甲基异丁酮和丁醇的混合溶剂萃取茶汤中的茶多酚，与氨基酸分离后，加入碱性Ｃｕ３（ＰＯ４）２悬浮液反萃取并同茶多酚作用，离心沉降未作用的Ｃｕ３（ＰＯ４）２后，用原子吸收法测定Ｃｕ，可求得茶多酚的含量，本法可消除茶叶共存氨基酸的干扰，测定结果同标准方法一致，回收率范围为９４％－１０４％，平均标准偏差为３．１％。     

Syntheses of Novel Asymmetric Cyclopentanone Dyes and Measurement of Two－photon Absorption Cross－section

A simple synthesis route with a high yield of novel asymmetric cyclopentanone dyes 3a—3e and their highly two-photon up-converted fluorescences are reported. The dyes have good solubilities in most of ordi-nary solvents, a wide UV absorption wavelength range from 380—540 nm, and high fluorescence quantum yields. The two-photon absorption cross-sections of dyes 3a—M were measured in chloroform by a two-pho-ton induced fluorescence method. All of these properties of the new dyes make them suitable for being used as two-photon fluorescent probes.     

水杨酰腙与磷酰二氯的缩合反应

一些水杨酸的衍生物具有生物活性早有报道.本文研究水杨酰腙与硫代磷酰二氯或磷酰二氯缩合时可能发生的不同关环方式,并通过对反应产物的生物活性测定寻找有效的杀菌剂. 我们发现,在三乙胺存在下水杨酰腙1与硫代磷酰二氯2在四氢呋喃中反应主要以酮式关环生成3类化合物,而与磷酰二氯反应则主要以烯醇式关环生成4类化合物.