低分子量壳聚糖的Sm3+配合物的合成和表征

壳聚糖经双氧水降解制得低分子量壳聚糖,低分子量壳聚糖与Sm3 反应制得配合物。分别用红外、紫外、荧光等测试手段对低分子量壳聚糖及其与Sm3 形成的配合物的结构和性能进行了表征。结果表明,低分子量壳聚糖与Sm3 发生了螯合作用,形成了较稳定的配合物。     

细胞色素C在离子液体修饰电极上的电化学行为

分别合成了疏水和亲水性咪唑类离子液体,并制备了相应的两种离子液体修饰的玻碳电极。循环伏安法测量结果显示,细胞色素C在离子液体修饰的玻碳电极上的电子传递过程为一扩散控制的准可逆反应,表明咪唑类离子液体也可用作细胞色素C电子传递的有效促进剂。电化学交流阻抗谱的测量结果得到了与循环伏安相同的结论。     

Evolution of Er^3＋ Distribution in the Oxyfluoride Glass Ceramics with Heating

The distribution characteristics of Er3+ ions doped in the oxyfluoride glass ceramics containing LaF3 nanocrystals heat-treated at 650 ℃ for different durations were investigated. The results of the integral absorption cross-section analysis demonstrated that the partition fraction of Er3+ in LaF3 nanocrystals increases with prolonging of heating time. The anomalous phenomena of Er3+ emissions in the up-and the down-conversion fluorescence spectra are well explained based on the calculated results.     

Synthesis and Crystal Structure of 3-Benzoyl-7,7-dimethyl-4-phenyl-2-phenylamino-4,6,7,8-tetrahydro-chromen-5-one

The title compound (C30H27NO3) was synthesized via a one-pot procedure starting from β-benzoylthioacetanilide, benzaldehyde and 5,5-dimethyl-1,3-cyclohexanedione, and its struc- ture was determined by single-crystal X-ray diffraction analysis. The crystal belongs to triclinic system, space group P, with a = 6.325(2), b = 11.243(3), c = 17.553(4) , α = 87.306(4), β = 80.822(4), γ = 77.798(4)°, V = 1204.2(5) 3, Z = 2, Mr = 449.53, Dc = 1.240 g/cm3, μ = 0.080 mm-1, F(000) = 476, the final R = 0.0459 and wR = 0.0970 for 2301 observed reflections with I > 2σ(I).     

Theoretical Study on the Hetero-Diels-Alder Reactions between 3-Pyridinedithioesters and 1-Phenylsulfanylbutadiene

The mechanism, catalytic effect and solvent effect of the hetero-Diels-Alder reac- tions between 3-pyridinedithioesters and 1-phenylsulfanylbutadiene have been studied theoretically using density functional theory (DFT) at the B3LYP/6-31G(d) level. The results show that all of these reactions proceed in a concerted but asynchronous way. In some reactions the formation of C-S bond is prior to that of C-C bond and the opposite results are found in other reactions. The BF3 catalyst may lower the activation barriers by changing the energies of LUMO for 3-pyridine- dithioester. THF solvent has trivial influence on the potential energy surface of these reactions. With the BF3-catalyzed reactions, regioselectivity and stereoselectivity observed experimentally were predicted correctly by calculations and these results originate probably from C-H···F interaction in two transition states.     

Synthesis and Crystal Structure of 1,2-Bis-（p-nitrophenylsulfonamido）-4,5-dinitrobenzene

The title compound, 1,2-bis-(p-nitro-phenylsulfonamido)-4,5-dinitrobenzene, was synthesized and characterized by elemental analysis, IR and 1H NMR. A pale yellow prism crystal of C23H26N8O13S2 (Mr = 686.64) was obtained in DMF solution and determined by single-crystal X-ray diffraction method. It crystallizes in triclinic system, space group P1 with a = 10.346(4), b = 12.210(5), c = 12.976(5) , α = 108.220(8), β = 99.482(4), γ = 95.490(4)°, V = 1516.7(10) 3, Z = 2, Dc = 1.504 g/cm3, F(000) = 712, μ = 0.254, Mr = 686.64, the final R = 0.0561 and wR = 0.1487. One sulfonamido group of the title compound is deprotoned and forms N(3)=C(13). The crystal involves N,N-dimethylamine from the decomposition of DMF and the proton is transferred to N,N- dimethylamine. It is a strong proof for the characterization of deprotoned recognition compound by X-ray single-crystal structure.     

基于离子迁移谱的假币用纸快速检测及溯源

该文采用离子迁移谱（IMS）对20种假币用纸进行分析,通过快速检测假币用纸中的可挥发性组分,构建假币用纸的指纹谱图库。基于主成分分析（PCA）和层次聚类分析（HCA）对迁移时间8～17.5 ms范围的迁移谱信息进行处理,从而对假币用纸进行分类。PCA可将同种假币用纸聚类,HCA则可进一步将20种假币用纸准确分类,其对6个未知来源的半成品假币的分类正确率达83.33%。结果表明,IMS快速检测分析是比较和分类假币用纸的有效方法。     

重要传感材料荧光共轭聚合物PPESO3的一种新的简便合成路线

本文提出了一种新的简便得多的合成路线, 既避免了BBr3的使用, 又简化了反应步骤, 使PPESO3的合成简单易行, 为更广泛地对其进行研究与应用提供了便利条件. 此外, 本文还研究了PPESO3与非离子表面活性剂(聚乙烯吡咯烷酮, PVP)之间的相互作用, 结果表明, PVP与PPESO3形成了稳定的络合体, 可以有效地打破聚合物在水溶液中的聚集, 提高荧光量子产率.     

1,3-二氧戊环基LiCF3SO3电解液对锂硫电池正极材料单质硫的电化学性能影响

测试了二元和多元溶剂组分的1,3-二氧戊环基LiCF3SO3电解液的粘度、离子电导率和单质硫的溶解度. 研究结果表明, 由较强的给电子能力溶剂组成的低粘度电解液较容易提高单质硫的氧化还原反应活性和可逆性能, 有利于提高单质硫在2.10 V附近的低放电平台电位和放电比容量. DOL-DME LiCF3SO3电解液能够较好地改善单质硫电极的表面钝化层结构, 促进电活性物质离子扩散和降低界面电荷传递阻抗, 从而表现出很好的放电倍率特性. 在室温下充放电流密度分别为0.1和0.2 mA/cm2时, 单质硫的首次放电比容量为792 mA·h/g, 第29次放电比容量达到412 mA·h/g.     

室温离子液体中合成方钠石的研究

本文以离子液体为溶剂, 在常压下采用离子液体热合成方法合成了方钠石分子筛.