质子化双氧/硫杂卟啉内氢原子迁移反应的理论研究

在确定各反应体系反应物、产物稳定构象的基础上, 采用B3LYP/6-31G**方法在Gaussian 03程序下, 对质子化的双氧/硫杂卟啉的内氢迁移(IHAT)反应进行研究, 寻找并优化相应的过渡态, 比较其迁移反应速率的差异. 计算结果表明, 质子化双氧/硫杂卟啉的构象稳定性仍然是由芳香性、空间位阻、静电作用共同决定的. 质子化后的双取代体系的内氢迁移反应速率大小差异显著, 内环取代对IHAT反应速率的影响主要来源于电子效应, 而非构象变化; 且双取代对体系IHAT反应速率的影响要远大于单取代.     

染料敏化太阳电池用聚合物电解质

综述了本研究小组近年来用于染料敏化太阳电池中聚合物电解质的研究概况.设计合成了几类性能优良的聚合物电解质,较好地改进了液体电解质染料敏化太阳电池(DSSC)的使用稳定性,研究结果具有实际应用的价值,并提出了此领域研究今后的发展方向.     

固相萃取/高效液相色谱法测定地表水中磺酰脲类农药的研究

建立了固相萃取/高效液相色谱法(SPE/HPLC)同时测定地表水中五种磺酰脲类农药的方法。研究了固相萃取提取、净化方法,优化了高效液相色谱条件并用二极管阵列检测器进行定量分析。五种磺酰脲类农药在0.1~10.0μg/mL范围内线性良好,相关系数在0.9992~0.9998之间,相对标准偏差在1.8%~4.1%之间,平均回收率为72.8%~103%。本方法中五种磺酰脲类农药的检出限在0.02~0.22 ng/mL范围。用该法分析了某水域地表水,取得满意结果,表明本方法具有一定的实用性。     

MgSO4-Na2SO4-H2O三元体系100 ℃沸腾蒸发非平衡态成盐特征

采用140 ℃恒温热源, 对MgSO4-Na2SO4-H2O体系溶液进行100 ℃恒温沸腾蒸发, 蒸发强度为140～160 g/(h•L), 监测初始析盐点和固相析出后固液相组成随蒸发进程的变化, 总结成盐特征, 提出反映非平衡态成盐特征的初级成盐区、扩展成盐区等概念. 研究发现(1)平衡相图上的同成分复盐3Na2SO4• MgSO4和Na2SO4• MgSO4•2.5H2O变为异成分复盐; (2)对Na2SO4和3Na2SO4•MgSO4的平衡共饱和液蒸发, 首先析出的是Na2SO4, 其单固相析出率为60.86%, 3Na2SO4•MgSO4和Na2SO4•MgSO4•2.5H2O的共饱和液也具有相同特征; (3)蒸发过程的初级成盐区与溶解平衡相区有显著区别. 用硫酸钠的耶涅克指数表示相区宽度, Na2SO4初级成盐区宽度从平衡态的21.02扩大到32.76; 而Na2SO4•MgSO4•2.5H2O则从41.40缩减为25.71; (4)在晶种存在的条件下, 各种盐的成盐区比初级成盐区有不同程度的扩展, 如Na2SO4, 3Na2SO4•MgSO4等盐的成盐区分别扩展了7.72和8.81. 扩展成盐区与初级成盐区的交叠形成了非平衡条件下特有的条件成盐区, 析盐种类取决于晶种的种类.     

Solid and Solution Structural Studies of Dimeric and Tetrameric Molybdenum（VI） Malate Complexes

Reactions of potassium molybdate with racemic malic acid （H3mal = C4H6O5） result in the isolation of two mesomeric molybdenum malate complexes K8[（MoO2）2O（R-mal）2][（MoO2）2O（Smal）2]-4H2O 1 and （Him）2K6[（MoO2）4O3（R-mal）2][（MoOE）4O3（S-mal）2]-8H2O 2. Complex 1 belongs to the monoclinic system, space group C2/c with a = 14.8637（3）, b = 6.9544（1）, c = 19.6783（5）A, β = 100.081（2）°, V = 2002.70（7） A^3, Mr = 1452.88, Z = 2, F（000） = 1416, T = 173 K, Dc = 2.409 g/cm3, fl（MoKa＇） = 2.167, R = 0.0283 and wR = 0.0733.2 is of triclinic system, space group P1^- with a = 8.7707（2）, b = 9.3310（3）, c = 17.9093（7）A, α= 83.781（3）, β = 85.626（2）, y= 84.822（2）°, V = 1447.84（8）A^3, Mr = 2160.68, Z = 1, F（000） = 1048, T = 173 K, Dc = 2.478 g/cm^3,μ（MoKα） = 2.230, R = 0.0234 and wR = 0.0584.1 is the first isolated dinuclear molybdenum（VI） malato complex in 1：1 molar ratio. The molybdenum atoms in the two complexes are six-coordinated in an approximately octahedral geometry. Two malates coordinate tridentately with the Mo atom via their α-alkoxy, α-carboxy and α-carboxy groups in 1 and 2. β-Carboxy group in 2 further links with the other two Mo atoms to give a tetrameric unit. The solution ^1H and ^13C NMR spectra indicate that dimeric malate molybdenum in 1 dissociates partly in solution and exists in an equilibrium with tetrameric species, while 2 is stable and retains its tetrameric structure without any dissociation.     

铽异烟酸哌嗪三元配合物的合成及其荧光性能

以醋酸铽,异烟酸和哌嗪为原料,合成了铽异烟酸哌嗪三元固体配合物,其结构经UV-vis,IR,TC-DTA和元素分析表征,并用荧光光谱测定了其荧光性能.     

Gd1-xSrxCoO3-δ和Gd0.8Sr0.2Co1-yFeyO3-δ系阴极材料的制备和性能

采用甘氨酸-硝酸盐(GNP)法合成了新型中温固体氧化物燃料电池(IT.SOFC)的阴极材料Gd1-xSrxCoO3-δ(x=0-0.5)和Gd.0.8Sr0.2Co1-yFeyO3-δ(y=0-1),所合成的初始粉体在800℃下煅烧12 h后均形成了钙钛矿结构的单相固溶体.研究发现,Gd1-xSrxCoO3-δ(GSC)的电导率在600℃时达到了559 S·cm-1,由Ce0.8Cd0.2O2-δ(GDC)电解质和GSC-25GDC材料组成的对称电极在600℃和700℃的界面阻抗分别为0.170Ω·cm2和0.064Ω·cm2,活化能仅为87.8 kJ·mol-1,预示其可以作为ITSOFC较为理想的阴极备选材料;随着Fe3 离子含量的增加,Gd0.8Sr0.2Co1-yFeyO3-δ系列阴极材料的热膨胀系数显著降低,但其电导率也急速下降;此外,通过调整Gd0.8Sr0.2CoO3-δ与GDC的比例可以制备出热膨胀系数与GDC电解质匹配、性能良好的Cd0.8Sr0.2CoO3-δ/GDC复合阴极材料.     

Pressure- and temperature-induced association of arborescent polystyrene-graft-poly(ethylene oxide) copolymers at the air-water interface

The influence of surface pressure and subphase temperature on the association of arborescent polystyrene- graft-poly(ethylene oxide) (PS- g-PEO) copolymers at the air-water interface was investigated using the Langmuir balance and atomic force microscopy (AFM) techniques. These dendritic molecules form stable condensed monolayers with surface compressional moduli >250 mN/m. The variation in film thickness observed as a function of surface pressure suggests that at low surface pressures (gaslike phase) the PEO chains remain adsorbed at the air-water interface. At higher surface pressures (condensed phase), the PEO chains partially desorb into the subphase and adopt a more brushlike conformation. Large islandlike clusters with a broad size distribution were observed for samples with PEO contents of up to 15% by weight. In contrast, copolymers with PEO contents of 22-43% displayed enhanced side-by-side association into ribbonlike superstructures upon compression. The same effect was observed even in the absence of compression when the subphase temperature was increased from 12 to 27 degrees C. The temperature-induced association was attributed to increased van der Waals attractive forces between the PS cores relative to the steric repulsive forces between PEO chains in the coronas because the solvent quality for the PEO segments decreased at higher temperatures. The restricted number of superstructures observed for arborescent copolymers as compared with linear- and star-branched PS-PEO block copolymers is attributed to the enhanced structural rigidity of the molecules due to branching.     

配位化合物[Cd(hca)2(H2O)3](H2O)2，[Cu(hca)2(phen)]的合成与表征

配合物1由醋酸镉和Nahca(对羟基肉桂酸钠)在水溶液中反应得到,配合物2由醋酸铜,Hhca和phen在水和乙醇混合溶液中反应得到。配合物1属正交晶系,Pbcn空间群。配合物2属单斜晶系,C2/c空间群。配合物1和2中配体中的羧酸根与金属离子都是螯合配位的,末端羟基没有参与配位。配合物1和2的结构中都包含了丰富的氢键。通过氢键作用,配合物1形成了三维网状超分子结构,配合物2形成了二维层状超分子结构。     

SYNTHESIS OF AB AND ABA TYPES POLYSTYRENE (A)-POLYOXYETHYLENE(B) BLOCK COPOLYMERS AND CHARACTERIZATION OF THEIR STRUCTURES

α-Phenyl ethyl potassium was synthesized and used in the preparation of AB type polysty-rene (A)-polyoxyethylene (B) block copolymer. The effects of polymerization time and temperaturewere studied. ABA type block copolymers were prepared by combining AB type block copolymerscontaining one hydroxyl end group using toluene diisocyanate as coupling agent. Both copolymerswere purified, characterized by NMR, IR, UV. DSC, polarized microscopy and X-ray diffractionmethod and compared with mixture of homopolymers.