不同形貌Ag_3PO_4的表面自由能及原位光催化过程的热力学和动力学参数

<正>目前,在利用表面能研究纳米催化剂形貌效应时,多以催化剂表面原子排布或不同晶面的夹角与密勒指数间的关系来定性描述表面能高低[1,2],或利用密度泛函理论对表面能进行理论计算[3,4],但其数值可能会因计算方法和模型不符而与真实值存在偏差,而表面能的实验测定至今仍无精确、可靠、通用的方法[5].因此发展一种准确获取表面能的普适性方法并与材料的催化性能相关联非常必要.微量热技术能对体系变化过程进行实时监测,通过体系变化过程的热力学和动力学参数获取纳米材料的     

基于石墨烯的毒死蜱分子印迹电化学传感器的制备及对毒死蜱的测定

利用分子印迹技术,以马来松香丙烯酸乙二醇酯为交联剂,使用自由基热聚合法在石墨烯修饰的玻碳电极表面合成毒死蜱( CPF)分子印迹聚合膜,制得了CPF分子印迹电化学传感器。采用循环伏安法、线性扫描伏安法和电化学交流阻抗法等,考察了此CPF分子印迹膜的电化学性能。在最佳检测条件下,传感器的峰电流与CPF浓度在2.0×10-7~1.0×10-5mol/L范围内呈线性关系,线性方程为Ip(μA)=-7.1834-0.2424C (μmol/L),相关系数r2=0.9959,检出限为6.7×10-8 mol/L(S/N=3)。构建了CPF分子印迹电化学传感器的动力学吸附模型,测得印迹传感器的印迹因子β=2.59,结合速率常数k=12.2324 s。传感器表现出良好的重现性和稳定性,并成功用于实际水样和蔬菜样品中CPF的测定,加标回收率为94.1%~101.4%。     

Charge Transfer Properties of Organic Semiconductor Molecules of Perylene Derivatives

The charge transfer rates of perylene and its four derivatives were studied at the level of B3LYP/6-31G** by density functional theory. The results showed that the perylene and its four derivatives belonged to the semiconductor molecules, which released energy when electron was injected. Therefore, they were suitable to be used as the electron injection material. The introduction of OH group can improve the electron transfer rate significantly. The formations of intramolecular hydrogen bonds were unfavorable to the hole transfer, but conducive to the electron transfer. The perylene derivatives, 2,5-3,4,5-(trifluorophenyl)ethynyl-8,11-3,4,5-trihydroxyphenyl ethynyl, designed in this article had the hole transfer rate of 1.57 cm2/V·s-1. Therefore, this kind of material will be potential hole transfer material with high transfer efficiency.     

Synthesis,Crystal Structure,Spectroscopic Characterization,Thermal Stability and Magnetic Properties of a Dinuclear Copper(Ⅱ) Complex

A new copper(Ⅱ) complex [Cu2(MNA)2(2,2‘-bipy)2]·2.5H2 O with methy-5-norbornene-2,3-dicarboxylic acid(MNA) and 2,2’-bipyridine as ligands has been synthesized in the mixed solvents of DMF and water.It crystallizes in monoclinic,space group P 1,with a = 10.4191(11),b = 12.8883(13),c = 16.1114(16) ?,α = 70.8090(10),β = 80.568(2),γ = 77.440(2)o,V = 1984.3(4) ?3,Dc = 1.551 g/cm3,Z = 2,F(000) = 962,the final GOOF = 1.051,R = 0.0431 and w R= 0.0980.The crystal structure shows that the whole molecule consists of two independent dinuclear units,in which two copper ions are bridged by two μ2-η1:η0 3-carboxylate groups of MNA2-.The coordination environment of Cu(Ⅱ) ion is Cu O3N2,giving a distorted square pyramidal geometry.The spectroscopic characterization,thermal stability and magnetic properties of the complex were investigated.     

电解铜箔表面电沉积Zn-Ni-P-La合金工艺

为了缓解我国高性能铜箔依靠进口的局面,进行了将类金属(P)和稀土金属(La)引入电解铜箔锌镍合金镀层中以获得高耐腐蚀性铜箔的实验。 利用电子能谱(XPS)、X射线衍射(XRD)、扫描电子显微镜(SEM)等技术手段分析镀层质量。 在最佳工艺下获得非晶态Zn-Ni-P-La合金镀层,镀层表面平整均匀、结晶致密,未钝化的情况下,铜箔镀件在180 ℃烘箱中保持1 h不变色,表现出较理想的抗氧化和抗腐蚀能力。 表明镀层中适量的P和稀土La对改善镀层质量有着重要的作用,具有较好的工业应用前景。     

β-环糊精修饰的荧光金纳米簇的合成及其在细胞成像上的应用

通过一锅法水相合成出一种β-环糊精修饰的荧光金簇。该新型金簇具有红色荧光发射、长时间的分散稳定性和荧光稳定性。透射电镜观察其平均粒径为(1.40±0.32)nm。激光共聚焦显示金簇分散在细胞质中,荧光随金簇浓度增加而增强。细胞毒性实验证实该金簇具有良好的生物相容性。表面修饰的β-环糊精,也为金簇载药或者靶向功能化提供了更多可能性,从而进一步拓宽其在生物医学方面的应用。     

两个有机锡对碘苯甲酸酯的合成、结构、热稳定性和除草活性

在乙醇-苯溶剂中,对碘苯甲酸分别与三苯基氢氧化锡、二丁基氧化锡反应,合成了2个有机锡对碘苯甲酸酯,Ph3Sn(p-IC6H4O2)(1)和{[n-Bu2Sn(p-I-C6H4O2)]2O}2(2)。经IR、1H NMR、元素分析和X射线单晶衍射对配合物进行了表征。配合物1属三斜晶系,空间群为P1,中心锡原子与苯基碳原子、羧基氧原子构成畸型四面体,并且分子间通过氢键和C-I…π共同作用形成二聚体结构;配合物2属单斜晶系,空间群为C2/c,配合物是以Sn2O2构成的平面四元环为中心的二聚体结构,并且分子间通过I…I共同作用形成了一维链状结构。热重分析表明,配合物1和2在230℃以下具有良好的热稳定性。配合物1、2对杂草刺苋(Amaranthus spinosus)、马齿苋(Portulaca oleracea)的抑制活性大于对农作物绿豆的影响,且配合物1的抑制活性高于配合物2的抑制活性,为刺苋、马齿苋除草剂研究提供了一种方法。     

Modulating ion current rectification generating high energy output in a single glass conical nanopore channel by concentration gradient

Inspired by biological systems that have the inherent skill to generate considerable bioelectricity from the salt content in fluids with highly selective ion channels and pumps on cell membranes,herein,a fully abiotic,single glass conical nanopores energy-harvesting is demonstrated.Ion current rectification(ICR)in negatively charged glass conical nanopores is shown to be controlled by the electrolyte concentration gradient depending on the direction of ion diffusion.The degree of ICR is enhanced with the increasing forward concentration difference.An unusual rectification inversion is observed when the concentration gradient is reversely applied.The maximum power output with the individual nanopore approaches10~4pW.This facile and cost-efficient energy-harvesting system has the potential to power tiny biomedical devices or construct future clean-energy recovery plants.     

高师“化学教学论实验”课程项目化学习的教学实践探索

立足于教学实践,探讨了"自主、合作、探究"模式下高师"化学教学论实验"课程中项目化学习的设计思路、实施模式和实施程序。教学实践说明将项目化学习应用于"化学教学论实验"课程,能够有效提升化学师范生的实验教学能力。