结构规整有序的寡聚噻吩修饰9,9'-螺二芴衍生物的光物理性质及其电化学聚合

研究了结构规整有序的寡聚噻吩修饰的9,9'-螺二芴衍生物在溶液中和在固体膜状态下的光物理性质, 发现在四氢呋喃的稀溶液中, 随着有效共轭长度的增加这些化合物的最大吸收峰和发射峰发生了明显的红移. 实验结果表明, 9,9'-螺二芴骨架中的9位螺碳原子明显地阻断了二个共轭片段的共轭效应, 使它们成为了二个独立的共轭链节. 此外, 还进一步研究了这些化合物的电化学聚合性质.     

Enantioselective Alkynylation of Ketones Promoted by β-Sulfonamide Alcohol-Titanium Complexes

A readily available β-sulfonamide alcohol-titanium complex was found to be effective on promoting the asymmetric addition reaction of an alkynylzinc reagent to unactivated simple ketones under very mild conditions. And the corresponding chiral tertiary propargylic alcohols were obtained with enantiomeric excesses of up to 86%, which provided a simple, practical and inexpensive method to generate chiral tertiary propargylic alcohols.     

硝酸二(α-羟基异丁酸)二水合钕的合成、表征及晶体结构

合成的标题配合物Nd(C_4H_7O_3)_2·NO_3·2H_2O晶体属C2/c空间群,晶胞参数:a=0.8996(1)nm,b=0.8601(1)nm,c=2.1111(3)nm,β=92.38(1)°Z=4,晶体中配合物呈聚合链状结构,硝酸根无序分布在靠近对称中心的2个相关位置,钕的配位数为8。     

Polymerization of styrene catalyzed by rare earth Schiff base complexes

The rare earth Schiff base complex Nd (H₂Salen)₂Cl₃·2C₂H₅OH was synthesized by a simple and convenient method and characterized by IR and elemental analysis. The catalyst system composed of Nd (H₂Salen)₂Cl₃·2C₂H₅OH/Al(i-Bu)₃/CCl₄ is effective for the polymerization of styrene (St). The optimum conditions are as follows: [St]/[Nd] = 1000, [CCl₄]/[Nd] = 9, [Al]/[Nd] = 30, and polymerization at 50°C for 20 h. The resulting polystyrene was characterized by NMR and GPC. The results of NMR show that the polymer obtained had a stereoregularity with 52.3% isotacticity and 47.7% syndiotacticity without any random structure. __________ Translated from Journal of Zhejiang University (Science Edition), 2007, 34(2): 189–196 [译自: 浙江大学学报(理学版)]     

Density Functional Theory Study on the Adsorption of CN on Transition Metal M（100） （M = Ni,Pd, Pt,Cu, Ag and Au） Surfaces

The adsorption of cyanide on the top site of a series of transition metal M（100） （M = Cu, Ag, Au, Ni, Pd, Pt） surfaces via carbon and nitrogen atoms respectively, with the CN axis perpendicular to the surface, has been studied by means of density functional theory and cluster model. Geometry, adsorption energy and vibrational frequencies have been determined, and the present calculations show that the adsorption of CN through C-end on metal surface is more favorable than that via N-end for the same surface. The vibrational frequencies of CN for C-down configuration on surface are blue-shifted with respect to the free CN, which is contrary to the change of vibrational frequencies when CN is adsorbed by N-down structure. Furthermore, the charge transfer from surface to CN causes the increase of surface work function.     

高效液相色谱法检测水产品中磺胺类和乙胺嘧啶药物残留

用高效液相色谱法检测水产品中磺胺类、乙胺嘧啶等合成抗茵剂残留.样品以乙腈、二氯甲烷、乙酸乙酯以体积比2比1比1为提取剂,经脱脂、净化、浓缩,用流动相溶解.用高效液相色谱法紫外检测器测定.通过梯度洗脱将7种磺胺类、乙胺嘧啶进行分离.各标准曲线线性范围为0.05～2.0 mg·L-1,相关系数为0.983 7～0.997 5,回收率分别为62.2%～88.6%,相对标准偏差为5.85%～8.12%(n=7),检出限(S/N=3)为10～50 μg·kg-1.     

高效液相色谱-质谱联用法检测烤鳗中环丙沙星

烤鳗样品中的环丙沙星分两次用经稀甲酸（1＋99）酸化的乙腈提取。收集上层清液用乙腈定容为25.0mL,分取10．0mL,在40℃氮气吹干后溶于流动相溶液2．0mL中,加入正己烷2．0mL,萃取后取10．0μL下层溶液注入于高效液相色谱-质谱分析仪中。在HPLC分析中,用XBridge^TM Shied PR18柱（250mm×3．0mm,5μm）,以体积比15比15比70混合的甲醇、乙腈和稀甲酸（2＋998）组成的混合液为流动相,并采用荧光检测（FD）（激发波长275nm,发射波长445nm）。在MS分析中,采用选择离子监测（SIM）技术在电喷雾电离正离子[ESI（＋）]模式下检测,定量离子为m／z 331．9[M＋H]^＋。检测信号的峰面积与环丙沙星浓度之间在100．0～2500．0μg·L^-1（HPLC-FD法）和20．0～500．0μg·L^-1 MS-SIM-ESI（＋）法]范围内呈线性关系,其测定限（n=10）依次为50．0,10．0μg·kg^-1。在3个浓度水平上加入环丙沙星标准溶液进行精密度和回收试验,所得相对标准偏差（n=6）均小于6．5％,回收率在83．0%～99．0%之间。     

邻氰基-D，L-苯丙氨酸盐酸盐的合成与表征

氨基酸是构成多肽的基本单位,肽链中不同的氨基酸及氨基酸所含基团的不同使其在化学和生物活性等方面有着不同的性质。通过改变肽链中不同氨基酸来修饰肽链的结构和环境,能赋子肽链新的功能。天然氨基酸由于结构的原因,无法满足特殊的需要。随着生物化学合成、分离和测试技术的     

海藻酸钠的疏水改性及在药物控释中的应用

海藻酸盐是一种由β-D-甘露糖酸盐(M)和α-L-古罗糖酸盐(G)连接而成的天然高分子,广泛存在于各类棕色海藻中,可与多价阳离子形成凝胶,成胶条件温和,该凝胶在生物体内以酶解方式生成甘露糖醛酸和葡萄糖醛酸,对机体无毒性、无免疫原性,适合作为释放或包埋药物、蛋白质与细胞的微胶囊.     

BaO-Y2O3(La2O3)-CuO三元系相图的研究

本文采用X射线衍射,热学分析、超导电性测量等方法测定了La₂O₃-CuO,BaO-CuO,Y₂O₃-CuO二元系相图,BaO-La₂O₃-CuO,BaO-Y₂O₃-CuO三元系室温截面。在这两个三元系的富CuO区,存在Ba_xLa_2-x CuO₄(x≤0.07),BaLaCu₂O_5+δ,BaLa₄Cu₅O_14+δ,BaLa₂Cu₂O₆和Ba₂YCu₃O_9-y,BaY₂CuO₉化合物。Ba_xLa_2-x,CuO₄(x≤0.07),BaLa₄Cu₅O_14+δ,BaLaCu₂O_5+δ,BaLa₂Cu₂O₆均属四方晶系,点阵常数分别为a=5.356,c=13.20;a=8.660,c=3.863;a=3.917,c=11.75;a=3.992,c=19.96.Ba₂YCu₃O_9-y属正交畸变钙钛矿结构,a=3.892,b=3.824,c=11.64,空间群为Pmmm。BaY₂CuO₅具有正交结构,a=7.123,b=12.163,c=5.649;空间群为Pbnm。研究了组成与超导电性的关系,考查了烧结温度对Ba₂YCu₃O_9-y化合物结构和超导电性的影响,并对超导电性产生的原因进行了讨论。