4-卤代苯甲酸铽配合物荧光性能的研究

以4-氯苯甲酸(4-ClBA)、4-溴苯甲酸(4-BrBA)和4-碘苯甲酸(4-IBA)为配体合成了三种4-卤代苯甲酸铽的稀土配合物Tb(4-ClBA)3,Tb(4-BrBA)3和Tb(4-IBA)3,紫外可见光吸收光谱表明,相同摩尔浓度的Tb(4-IBA)3的紫外吸收最强,Tb(4-BrBA)3的紫外吸收强度次之,Tb(4-ClBA)3的紫外吸收最弱,而荧光发射光谱表明,Tb(4-IBA)3和Tb(4-BrBA)3的荧光发射强度远小于Tb(4-ClBA)3的.从配体的结构及配体能级、稀土离子Tb3+能级、配体到稀土离子之间的能量传递等角度对该试验结果进行了分析探讨,结果表明苯甲酸对位的碘原子、溴原子和氯原子与苯环上的碳原子所形成的碳卤键热振动的不同是造成三种稀土配合物荧光强度差别较大的本质原因.     

Environmental monitoring using a conventional photographic digital camera for multianalyte disposable optical sensors

The primary interest of this study concerns the use of an inexpensive photographic digital camera as the detection system, using its own flash as the source of light to present a new analytical procedure to measure disposable multianalyte optical sensors for potassium, magnesium, hardness and conventional pH test strips. The camera arrangement was designed in a fixed position over an optical board with controllable ambient conditions. After acquiring the digital image, the analytical information contained in each test zone is analyzed using theRGB colour space. Reflectance measurements were developed to study the colourimetric and spectral characteristics of the test zones. We obtained the following application ranges and precision in terms of relative standard deviation (RSD %): for potassium from 3.2 × 10⁻⁷ to 0.1 M with a precision between 3.3 and 4.0%, for magnesium from 2.7 × 10⁻⁶ to 1.5 M showing a precision between 4.7 and 7.8% and finally for hardness from 4.3 × 10⁻² to 200,000 mg L⁻¹ CaCO₃ and between 5.1 and 7.0%. Moreover, the analytical characteristics of several optical procedures were compared with the results presented here. The proposed method was statistically validated against a reference procedure using samples of water from different sources and beverages, indicating that there are no significant statistical differences at a 95% confidence level.     

基于分子内电荷转移的阴离子比率荧光分子探针

设计合成了一种基于4-甲基-1-羟基二苯甲酮对硝基苯腙的比色和比率荧光阴离子受体1。此类受体以羟基和腙单元为识别位点,以硝基苯基为信号报告基团。向受体1的DMSO溶液中加入AcO-、H2PO4-、F-后,溶液颜色由黄色变为紫红色,而加入所研究的其它阴离子则无变化,从而实现对AcO-、H2PO4-、F-这三种离子的裸眼识别。利用紫外-可见吸收光谱、荧光光谱考察了其与AcO-,H2PO4-,F-,Cl-,Br-,I-等阴离子的识别作用。1H NMR滴定为受体分子与阴离子之间氢键作用本质提供了有力证据。     

Peroxyoxalate Chemiluminescence Based on Fluorescent Conjugated Polymer for the Determination of Triton X-100

A novel peroxyoxalate chemiluminescence system has been designed for the determination of Triton X‐100 (TX‐100), in which a hydrophobic fluorescent conjugated polymer, poly[2,5‐bisnonyloxy‐1,4‐phenylene‐ethynylene‐9,10‐anthrylene] (PPEA) was employed as a fluorophor. A strong enhanced intensity of chemiluminescence (CL) was observed in the presence of TX‐100, due to the improved emission efficiency of PPEA in the presence of TX‐100. Under optimum conditions, the detection range of Triton X‐100 is between 1.0×10^?7 and 1.0× 10^?4 mol·L^?1, with a detection limit at 6.0×10^?8 mol·L^?1. The relative standard deviation is 2.4% (n=6) for 1.0×10^?6 mol·L^?1 Triton X‐100. This method provides satisfying results in the detection of TX‐100 in nature water and biological samples with high sensitivity and wide linear range.     

Structural and micro structural studies of PbO-doped SnO2 sensor for detection of methanol,propanol and acetone

In the present work the structural information of PbO-doped SnO2 thick film sensor has been investigated with X-ray diffractometer (XRD) and scanning electron microscope (SEM). Initially, SnO2 powder was derived using sol-gel process and was subsequently doped with PbO and ground up to nanosized particles. A suitable gas sensor structure was fabricated on 1′′×1′′ alumina substrate using thick film technology. The necessary paste for screen printing was also developed. SEM results showed sol-gel derived powder gets more agglomerated in the thick film form. The sensitivity of the sensor has been investigated at different temperatures (150 ?C?350 ?C) upon exposure to methanol, propanol and acetone, yielding a maximum at 250 ?C for acetone with 1 wt% PbO-doping while at 350 ?C for propanol with 3 wt% PbO-doping of the sensor. The reduction of particle size to nanometers (validated through XRD) leads to a dramatic improvement in sensitivity of sensors for the chosen organic vapors. The results also correlate well with the microstructural properties of the material and the dopant.     

1,3,5,7-四甲基-8-丙酰肼-二氟化硼-二吡咯甲烷柱前衍生高效液相色谱测定白酒中的脂肪醛

以合成的1,3,5,7-四甲基-8-丙酰肼-二氟化硼-二吡咯甲烷(BODIPY-丙酰肼)作为柱前荧光衍生试剂,用于高效液相色谱分离荧光法检测甲醛、乙醛、丙醛、丁醛、戊醛、己醛、庚醛、辛醛、壬醛、癸醛、十一醛、十二醛等12种脂肪醛.通过对衍生条件和分离条件进行优化,建立了测定脂肪醛的HPLC/FD新方法.衍生反应以H3P...     

荧光法研究meso-四对羧基苯基卟啉与牛血清白蛋白的作用机理

应用荧光法研究了meso-四对羧基苯基卟啉(TCP)与牛血清白蛋白(BSA)的结合反应.通过Stern-Volmer方程和Lineweaver-Burk双倒数函数关系式,测得25℃,36℃和42℃下反应的动态猝灭常数Ksv分别为1.17×105,1.06×105,1.01 ×105 L·mol-1,静态猝灭常数KLB分...     

水溶性七甲川吲哚菁染料的合成及其在含CTAB溶液中的光谱研究

本文合成并表征了一种水溶性七甲川吲哚菁染料,测试了染料在不同溶剂和不同浓度的表面活性剂十六烷基三甲基溴化铵(CTAB)中的吸收和荧光光谱性质.结果表明:染料的最大吸收和荧光发射光谱值(乙醇中)分别是796nm和813nm.随着溶剂的黏度增大,染料的荧光强度逐渐减弱.CTAB形成胶束前,随着CTAB浓度的增大,染料的吸收...     

YPO4/Eu3+微米束的尿素辅助水热合成及其发光性能

以Y( NO3)3、Eu( NO3)3和(NH4)2HPO4为原料,尿素作辅助剂,采用水热法成功制备出束状YPO4/Eu3+荧光粉.利用X射线粉末衍射仪、透射电镜、荧光光谱仪等研究了产物的晶体结构、形貌及发光特性;基于透射电镜分析探讨了YPO4/Eu3+微米束结构的形成机理.结果表明:YPO4/Eu3+属于四方晶系,空...     

Dopamine Sensor Based on a Composite of Silver Nanoparticles Implemented in the Electroactive Matrix of Calixarenes

A sensitive electrochemical sensor based on a composite containing silver nanoparticles and a redox active thiacalixarene with catechol fragments in the substituents at the lower rim has been developed and used for dopamine detection. The electrochemical investigation of thiacalixarene in homogeneous solution and on the electrode interface showed the reversible character of the redox conversion of catechol fragments and its involvement in the chemical reduction of silver which resulted in formation of uniform nanoparticles of 4–6 nm in diameter. The use of such a material for electrode modification made it possible to record a high amplitude cathodic signal at ?700 mV that was proportional to the dopamine concentration within 1 nM–1 µM. (limit of detection 0.5 nM).