Synthesis of poly (3,4-ethylenedioxythiophene)/sulfonated cellulose composites in different systems for the electrochemical sensing of paracetamol

Cellulose - In this paper, composites of poly (3,4-ethylenedioxythiophene) (PEDOT) and sulfonated cellulose (SC) were prepared by oxidative polymerization both in CHCl3 and H2O using different SC...     

Controllable length adjustment of polyaniline particle with temperature sensitive block copolymer as template

Although the diameter of conductive polymer nanoparticles can be controlled effectively, the uniformity of particle length is still very challenging. In this study, with the temperature‐sensitive block copolymer PS₁₁₁‐b‐PNIPAM₁₁₄ as the template, the morphology and size of polyaniline (PANI) particles had been controllably adjusted through the change of temperature. Additionally, the electrochemical performance of each sample was investigated. After PS₁₁₁‐b‐PNIPAM₁₁₄ was synthesized through the reversible addition‐fragmentation chain transfer radical polymerization (RAFT), with its vesicular micelle as the “template”, the PANI particles with uniform length distribution were prepared successfully at 40°C. The average length of PANI particles after template removal was 254.07 nm with a short tail distribution, which was closer to the average than the standard normal distribution. Electrochemical results of PANI showed that it had good electrochemical activity with fast charge and discharge ability. And, with the current density of 1 A·g^?1, its discharge‐specific capacitance could reach up to 805.61 F·g^?1.     

密度泛函理论研究混合团簇Al12X(X=Sc、Ti、V、Gr、Mn、Fe、Co、Ni、Cu、Zn)的结构和磁性

以四种13原子高对称性(Ih、Oh、D5h、D3h)密堆积结构为初始构型,通过不等价位原子替换,利用密度泛函理论系统研究了Al12 X(X=Sc、Ti、V、Cr、Mn、Fe、Co、Ni、Cu、Zn)掺杂团簇的结构及磁性.结果表明:除Al12 Cr和Al12Fe以外,其它Al12X团簇的基态结构均以Ih替换结构为主,其中前3d元素(X=Sc、Ti、V、Mn)倾向于表面位置替换,而后3d元素(X=Co、Ni、Cu、Zn)则倾向于中心位置替换;Al12 Cr和Al12Fe团簇以Oh结构的表面替换为基态结构;对多数3d元素(X=Ti、V、Cr、Fe、Co、Zn)其掺杂团簇均出现明显的近能同分异构现象;相较纯Al13团簇掺杂团簇普遍体现出磁性增强效应.     

Solid-state synthesis of poly(3',4'-dimethoxy-2,2':5',2"- terthiophene): comparison with poly(terthiophene) and poly(3',4'-ethylenedioxy-2,2':5',2"- terthiophene)

A new terthiophene monomer: 3',4'-dimethoxy-2,2':5',2"-terthiophene (TMT) was synthesized and characterized by 1H-NMR, 13C-NMR and FTIR. The solid-state oxidative polymerizations of TMT were performed in various ratios of oxidant (FeCl?) to monomer (TMT). The resulting polymers were characterized by 1H-NMR, FTIR, UV-vis-NIR, GPC, X-ray diffraction, CV, as well as TGA and conductivity measurements. The structure and properties of poly (TMT) were compared with those of polyterthiophene [poly(TT)] and poly (3',4'-ethylenedioxy-2,2':5',2"-terthiophene) [poly(TET)] prepared under the same polymerization conditions. After comparative analysis with poly(TT) and poly(TET), the effects of the dimethoxy substituent and FeCl? on the structural and physicochemical properties of the poly(TMT)s were discussed in depth. The comparison suggested that the dimethoxy-substituted polymer did not display higher crystallinity, thermal stability, conductivity and electrochemical activity than ethylenedioxy substituted one. The results also showed that the effect of FeCl? on poly(TMT) was similar that seen with the poly(TT), in which the oxidation degree, electrochemical activity and conductivity increased steadily with increasing [FeCl?/[TT] ratio. Furthermore, the poly(TMT) and poly(TT) are mostly made up of dimers with a small amount of higher molecular weight components.     

联苯胺与二苯胺共聚物的界面聚合及其表征

采用界面聚合法合成了聚联苯胺、聚二苯胺以及联苯二胺与二苯胺的共聚物。利用红外光谱(FT-IR)、紫外可见吸收光谱(UV-vis)、电子扫描显微镜(SEM)、X射线衍射(XRD)、循环伏安等手段初步探讨了单体配比对共聚物形貌、结构及性能的影响。结果表明:界面聚合法合成的聚联苯胺呈现微米级棒状分布,随着共聚物中二苯胺结构单元的增加,棒状结构消失,聚合物趋于颗粒状分布;共聚后聚合物的共轭程度下降,但其结晶性与电化学行为得到了一定的改善;当共聚物中联苯胺与二苯胺的单体摩尔比为1/2时,共聚物电化学行为最佳。     

β-萘磺酸掺杂聚苯胺纳米粒子的固相反应法制备及其表征

利用固相反应法制备了 β 萘磺酸掺杂的聚苯胺纳米粒子 ,并以红外光谱 (FTIR) ,扫描电子显微镜(SEM) ,透射电镜 (TEM) ,X 射线衍射 (XRD)以及粉末微电极等测试方法对其进行了表征 .结果表明 ,固相反应法合成的 β 萘磺酸掺杂聚苯胺粒子直径为 30～ 5 0nm ,聚苯胺分子链排列有序 ,晶化率较好 .粉末微电极的循环伏安测试表明 ,β 萘磺酸掺杂聚苯胺有较好的电化学活性 .     

Co对NiO-BaCO3催化剂催化N2O分解的促进影响

采用共沉淀法制备了一系列CoxBa1.5Ni9催化剂,用于N2O催化分解反应.研究发现,尽管Co加入纯NiO对反应不利,但在有BaCO3存在的情况下, Co则能够显著提高NiO的活性.这是由于Co增强了Ni–O键而对反应不利,但在BaCO3存在下则大大增加了Ni基催化剂的比表面积及活性位数目.     

N2O Decomposition Catalyzed by K+-doped Bi0.02Co

K⁺-doped Bi_0.02Co was investigated as catalyst for N₂O decomposition. It was found that the catalytic performance of the Bi_0.02Co catalyst, which was prepared by coprecipitation method, can be effectively modified by potassium cations via impregnation. The optimized K_0.01Bi_0.02Co catalyst exhibited much higher activity compared with Bi_0.02Co and K_0.01Co for the reaction in feed gas 0.2% N₂O/Ar, irrespective of the presence or absence of impurity gas(volume fraction) 5%O₂, 2%H₂O, 0.12%NO and 10%CO₂. Characterization of the catalysts with H₂ temperature programmed reduction(H₂-TPR) and O₂ temperature programmed desorption(O₂-TPD) indicate that the Co-O bond in Bi_0.02Co was weakened by the K⁺doping, and hence the K_0.01Bi_0.02Co catalyst has much higher turnover frequency(TOF) than Co₃O₄ spinel and Bi_0.02Co for the reaction.     

固相法合成苯胺与邻甲氧基苯胺共聚物及其性能

以苯胺和邻甲氧基苯胺为单体,甲磺酸为掺杂酸,用固相法合成了甲磺酸掺杂苯胺与邻甲氧基苯胺共聚物。 通过红外光谱、紫外可见吸收光谱、X射线衍射、透射电子显微镜、循环伏安和电导率等对共聚物进行了结构表征和性能测试。 结果表明,不同摩尔比的苯胺与邻甲氧基苯胺共聚物处于中间氧化态,随邻甲氧基苯胺含量的增大,共聚物的掺杂率降低。 共聚物具有较高的结晶性和纤维状形貌,当苯胺与邻甲氧基苯胺摩尔比为1∶1时,具有较高的电化学活性,其导电率为1.65 S/cm。     

教师工作量管理系统的设计与实现

TWMS1．0(Teacher Workload Management System，教师工作量管理系统)是我们开发的教学管理软件，已在我院投入使用．该系统是用流行的数据库前端开发工具Power Builder 8．0开发的，适用于新疆大学教职工工作量信息的管理、统计与分析．本文分析了系统的整体结构、功能以及特点，应用本系统能够科学、规范、高效率地做好教职工工作量的管理工作，提高工作效率。