聚乙烯吡咯烷酮-硫化镉修饰金电极伏安法测定合成饲料中替米考星的含量北大核心CSCD

制备了聚乙烯吡咯烷酮-硫化镉(PVP-CdS)修饰金电极,用循环伏安法研究了替米考星在该修饰电极上的电化学行为,用差分脉冲伏安法测定替米考星。结果表明:在扫描速率为100mV·s^(-1),静止时间为10s时,替米考星在pH 7.50的磷酸盐缓冲溶液中于0.93V左右产生一个氧化峰。PVP-CdS修饰金电极对替米考星的电化学过程有较显著的催化作用。替米考星的质量浓度在0.5~300mg·L^(-1)内与其在PVP-CdS金电极上对应的氧化峰电流呈线性关系,检出限为0.2mg·L^(-1)。以空白样品为基体进行加标回收试验,所得回收率为93.0%~97.5%,测定值的相对标准偏差(n=5)为2.7%~4.1%。     

硫化镉量子点增敏化学发光体系测定痕量苯酚的研究

在碱性条件下,硫化镉量子点对鲁米诺-H2O2化学发光体系具有显著的增敏作用,而苯酚对该体系的化学发光有强烈抑制作用,以此建立了流动注射化学发光检测苯酚的新方法.在优化实验条件下,苯酚浓度在5.0×10-9 ～5.0×10-7g/L(r=0.9935)和5.0×10-6 ～1.0×10-3g/L(r=0.9982)范围内...     

纳米硫化镉修饰玻碳电极对血红蛋白的直接电化学和生物电催化

0IntroductionStudies of direct electrochemistry of proteins orenzymes at electrodes can serve as a basis for build-ing electrochemical biosensors,enzymatic bioreactors,and biomedical devices[1].This approach simplifiessuch devices without using mediators and is of partic-ular significance for fabricating the third generationbiosensors[2].For example,if a protein or enzyme im-mobilized on electrode surface is capable of directelectron transfer without loss of bioactivities,it can beused in the …     

聚乙烯吡咯烷酮修饰碳糊电极上酪氨酸的电化学研究及其测定

研究了酪氨酸在聚乙烯吡咯烷酮修饰碳糊电极的伏安行为,优化了测定条件,在此基础上建立了一种直接测定酪氨酸的电分析方法。氧化峰电流与酪氨酸的浓度在2×10-7～5×10-5mol·L-1之间有良好的线性关系,开路富集3min,检出限为1×10-7mol·L-1。用此方法测定了酒样和人尿中酪氨酸的含量,结果满意。     

高分子模板对CdS量子点制备及其光催化性能的影响

分别以球形聚酰胺-胺(PAMAM)树形分子和线形聚乙烯吡咯烷酮(PVP)两种结构不同的高分子为模板, 原位制备了分散良好的CdS量子点(CdS QDs), 并以甲基橙为降解对象, 研究了高分子模板结构对CdS量子点的制备和光催化性能的影响. 结果表明, 以PAMAM 树形分子为模板制备的CdS量子点(CdS QDs/PAMAM)比以PVP为模板制备的CdS量子点(CdS QDs/PVP)的尺寸分布更窄, 激子吸收峰更明显, 光致发光(PL)强度更高|并且在量子点尺寸接近的情况下, CdS QDs/PAMAM的催化效率明显高于CdS QDs/PVP. 这是由于PAMAM树形分子独特的结构有利于生成尺寸均匀的CdS量子点, 且不易钝化量子点表面的活性位点|而线性的PVP分子量分布较宽, 使制备的量子点的尺寸分布较宽, 且PVP分子链缠绕在CdS量子点表面, 钝化了部分活性位点, 降低催化效率. 此外, CdS QDs/PAMAM的催化能力随粒径减小而增大.     

阳离子型聚乙烯吡咯烷酮的制备及其负载RNA性能

将二甲基二烯丙基氯化铵（DADMAC）与乙烯吡咯烷酮（VP）共聚得到阳离子型的聚乙烯吡咯烷酮（CPVP）,并分别合成了聚二甲基二烯丙基氯化铵（PDADMAC）和聚乙烯吡咯烷酮（PVP）均聚物,用粘度法测定了三者的粘均相对分子质量,用红外光谱表征了其结构。 将合成的CPVP与核糖核酸（RNA）以不同比例混合,研究CPVP负载RNA的能力,并与PDADMAC及PVP的负载性能做比较。 结果发现,与PDADMAC及PVP相比,当CPVP与RNA按质量比2∶1混合时,形成的复合体纳米粒的平均粒径约为300 nm,分散度指数为0.0966,粒径分布较窄。     

交联聚乙烯基吡咯烷酮的合成及其性能研究

以乙烯基吡咯烷酮（NVP）为单体，二乙烯基苯为交联剂，AIBN为引发剂，采用悬浮聚合法合成了性能稳定的交联聚乙烯基吡咯烷酮（PVPP），研究了聚合温度，引发剂用量，交联剂用量和反应气氛等因素对产率，溶胀性能和吸附性能的影响，并用红外光谱和扫描电镜等对产物的结构、性能和表面形貌进行了表征。     

对硫磷在聚乙烯吡咯烷酮修饰碳糊电极上的电化学行为及其分析研究

研究了对硫磷在聚乙烯吡咯烷酮(PVP)修饰碳糊电极(CPE)上的电化学行为,发现PVP能显著提高对硫磷的氧化还原峰电流.据此建立了一种直接测定对硫磷的电分析方法.对硫磷氧化峰电流与其浓度在2.5×10-8～1.0×10-6mol/L及1.0×10-6～1.0 × 10-5mol/L 范围内呈良好的线性关系,开路富集5 min后,检出限为7.5×10-9mol/L.在1.0×10-5mol/L的对硫磷试液中连续测定10次,其RSD为2.8%.用此方法测定了蔬菜中的对硫磷.     

基于氮掺杂石墨烯量子点/硫化镉纳米晶电化学发光传感器检测硫化氢

以柠檬酸和氨水为原料,用水热法制备了氮掺杂石墨烯量子点(NGQDs),与硫化镉纳米晶(CdS NCs)复合,构建了固态电化学发光(ECL)传感器,用于硫化氢(H₂S)的检测。采用紫外-可见吸收光谱和荧光光谱对NGQDs和CdS NCs进行了表征,同时对传感器的ECL和电化学行为进行了系统研究。结果表明,以H₂O₂为CdS NCs的共反应试剂时,NGQDs可增强CdS NCs的ECL信号,并且NGQDs/CdS NCs的稳定性增加。H₂S存在下,S^2-与过量的Cd²⁺发生键合作用,ECL值降低。在最优条件下, ECL变化值与H₂S浓度(2.0×10^-10～2.0×10^-5 mol/L)的对数呈良好的线性关系,检出限为6.7×10^-11 mol/L。采用本传感器测定血清中H₂S浓度,加标回收率为92.7%～103.8%。     

聚乙烯醇/聚乙烯吡咯烷酮碱性复合膜的制备及其性能

通过在不同浓度KOH溶液中进行掺杂,制备出了聚乙烯醇/聚乙烯吡咯烷酮(PVA/PVP)碱性聚合物电解质膜.详尽考察了膜的组成、微观结构、热稳定性、离子电导率和甲醇吸收率.结果表明,PVA与PVP两者具有较好的相容性,当m(PVA)∶m(PVP)=1∶0.5时,膜断面致密、均匀,未发生大尺度相分离.PVP的混入可以极大提高复合膜的电导率和热稳定性.当m(PVA)∶m(PVP)=1∶1时,复合膜的电导率可达2.01×10-3 S.cm-1.PVA/PVP/KOH膜的甲醇吸收率随温度的升高没有明显变化,100℃时其甲醇吸收率仅为同条件下Nafion 115膜的1/4.这表明该复合膜有望作为一种新型的碱性直接甲醇燃料电池用固体电解质膜且可提高膜的使用温度.     

纳米CoHCF修饰电极的制备及其对血红蛋白的电化学测定研究

A cobalt hexacyanoferrate （CoHCF） nanoparticle （size ca. 60 nm） chemically modified electrode （CME） was fabricated and the electrochemical behavior of hemoglobin （Hb） at this nanosized CoHCF CME was studied. In comparison with a bare glassy carbon electrode （GCE） and a general CoHCF CME electrodeposited in a traditional manner, the present nanosized CoHCF CME performed efficiently electrocatalytic reduction for Hb with relatively high sensitivity, stability, and longlife, Combined with liquid chromatography （LC）, the nanosized CoHCF CME was used as the electrochemical detector of Hb in the established flow injection analysis-electrochemical determination （FIA-ECD） system. The peak current was a linear function of concentrations in the range from 2.5×10^-8 to 5.0×10^-6mol/L for Hb, with detection limit of 1.4×10^-8 mol/L. The FIA-ECD system has been successfully applied to assess the Hb content of clinic blood samples with advantages of sensitiveness, speediness, easy control and small sample-consumption.     

Dendronized Cellulose Nanocrystals as Templates for Preparation of ZnS and CdS Quantum Dots

Cellulose nanocrystals (CNC) isolated from bleached bagasse pulp were modified with a second-generation isocyanate dendron (G2-dendron) to prepare dendronized cellulose nanocrystals (DCN). Transmission electron microscopy (TEM), elemental analysis for nitrogen, Fourier transform infrared (FTIR) and ¹³C magic angle spinning nuclear magnetic resonance (¹³C MAS NMR) proved occurrence of the modification of cellulose nanocrystals surfaces. The dendronized cellulose nanocrystals were used as templates for formation of ZnS and CdS quantum dots with uniform diameter at low temperature in water. The prepared DCN/QDs were highly soluble in water. TEM images showed that the size of the prepared quantum dots was about 5 nm in diameter. UV-Visible and fluorescence spectroscopy showed absorption and emission at wavelength values lower than that reported for bulk ZnS and CdS.     

纳米ZnO修饰电极的制备及其对血红蛋白, 细胞色素c的直接电化学研究

A novel electrochemical method as a sensitive and convenient technique for the determination of heme proteins based on their interaction with ZnO nanorods was developed. A ZnO nanorod modified glassy carbon electrode (ZnO/GCE) was prepared and the electrochemical behaviors of heme proteins, such as hemoglobin (HB) and cytochrome c (Cyt-c), on this modified electrode have been studied. The results showed that both HB and Cyt-c could be oxidized on the modified electrode and the oxidation currents were linear to the concentrations of the analytes in aqueous solutions. In addition, the results of flow injection analysis (FIA) further suggested the high stability and reproducibility of the ZnO nanorod modified electrode. So this method can be applied to the determination of HB and Cyt-c in biological systems.     

纳米银粒子修饰电极法测定血红蛋白

报道了一种利用纳米材料修饰电极检测血红蛋白的新方法。制作了以纳米银粒子修饰的银电极,并研究了血红蛋白在该修饰电极上的直接电化学行为。实验结果表明,血红蛋白在该修饰电极上具有良好的电流响应。在2.0×10-7~1.0×10-5mol/L浓度范围内,血红蛋白的氧化峰电流与其浓度呈良好线性关系;检出限为7.4×10-8mol/L。研究了该修饰电极对血红蛋白的催化机理,利用该电极所建立的方法实现了对血红蛋白的分析测定。     

血红蛋白在磷脂-月桂酸修饰的玻碳电极上的电化学行为及其分析应用

报道了血红蛋白（Hb）在磷脂-月桂酸修饰的玻碳电极上的电化学行为,在+0. 8～-0.7V (vs. Ag/AgCl)电位范围内,于pH6.0的0.01mol/L的KH_2PO_4- Na_2HPO_4底液中,血红蛋白产生不可逆的还原电流峰。还原峰电流与血红蛋白浓 度在1.25 * 10~(-8)～4.31 * 10~(-7) mol/L范围内呈良好线性关系。该电极可作 为检测血红蛋白的新型的高灵敏度电化学生物传感器。     

量子点微型光谱传感技术在水质实时监测中的应用

随着我国城市化进程加快和工业化程度加大,水环境保护问题愈发突出。水质的实时监测是水质治理的重要前提之一。从水质实时监测发展历程中的各项技术谈起,介绍和比较多种光学传感法,并着重聚焦于新兴的量子点微型光谱传感技术。量子点光谱仪是基于胶体量子点材料的重建式微型光谱仪,具有成本较低、性能优良、发展潜力大等诸多优势,目前已实际应用到水环境实时监测中。最后总结并展望了水质实时监测技术未来的发展方向。     

基于量子点涂料的柔性光阳极及碳基对电极的制备和优化

首先制备出量子点(QDs)/TiO_2涂料,分别采用丝网印刷法与刀刮法将涂料涂覆于ITO/PET柔性基底上,结果表明刀刮法制备量子点敏化太阳电池(QDSCs)效果更佳,且具有普适性。基于铜片对电极所组装的ZnCuInSe,CdSe和CdSeTe量子点半柔性QDSCs最高效率分别达2.83%,2.46%和1.99%。另外,我们对石墨纸进行表面化学修饰以提高亲水性,再通过简单的连续离子交换吸附法(SILAR)在石墨纸上负载Cu_xS纳米粒子,制备出Cu_xS/GP柔性对电极,进一步组装成全柔性QDSCs,获得了2.13%光电转化效率。     

基于量子点涂料的柔性光阳极及碳基对电极的制备和优化

首先制备出量子点（QDs）/TiO₂涂料,分别采用丝网印刷法与刀刮法将涂料涂覆于ITO/PET柔性基底上,结果表明刀刮法制备量子点敏化太阳电池（QDSCs）效果更佳,且具有普适性。基于铜片对电极所组装的ZnCuInSe,CdSe和CdSeTe量子点半柔性QDSCs最高效率分别达2.83%,2.46%和1.99%。另外,我们对石墨纸进行表面化学修饰以提高亲水性,再通过简单的连续离子交换吸附法（SILAR）在石墨纸上负载Cu_xS纳米粒子,制备出Cu_xS/GP柔性对电极,进一步组装成全柔性QDSCs,获得了2.13%光电转化效率。     

溶胶-凝胶血红蛋白电化学传感器的研制

运用溶胶-凝胶技术将血红蛋白(Hb)固载于玻碳电极(GC)表面,制得Hb/Sol-Gel/GC修饰电极,找出了制备Hb/Sol-Gel/GC修饰电极的最佳实验条件,建立了一种测定过氧化氢的新的、灵敏的方法.同时对该电极与过氧化氢的作用机理进行了探讨.     

Beyond OLED: Efficient Quantum Dot Light‐Emitting Diodes for Display and Lighting Application

The unique features of solution‐processed quantum dots (QDs) including emission tunability in the visible range, high‐quality saturated color and outstanding intrinsic stability in environment are highly desired in various application fields. Especially, for the preparation of wide color gamut displays, QDs with high photoluminescence quantum yield are deemed as the optimal fluorescent emitter that has been utilized in the backlight for liquid crystal display. Nevertheless, the commercialization of electrically driven self‐emissive quantum dot light‐emitting diode (QLED) display is the ultimate target due to its merits of high contrast, slim configuration and compatibility with flexible substrate. Through the great efforts devoted to material engineering and device configuration, astonishing progresses have been made in device performance, giving the QLED technology a great chance to compete with other counterparts for next‐generation displays. In this review, we retrospect the development roadmap of QLED technology and introduce the essential principles in the QLED devices. Moreover, we discuss the key factors that affect the QLED efficiency and lifetime. Finally, the advances in device architectures and pixel patterning are also summarized.