Tetracycline selective electrode based on molecularly imprinted polymer particles

<正>Tetracycline selective electrode using molecularly imprinted polymer particles as quasi-ionophore was constructed the first time, and its performance was carefully characterized.Due to the specific recognition of tetracycline by the particles,the selectivity coefficients for routine interferences were less than 10~(-4).Benefited from the absence of tetracycline in the sensitive membrane and the optimized composition of the inner filling solution,the limit of detection of the electrode was reduced to about 2.5×10~(-8) mol/ L.It exhibited a good electrode slope 57.6 mV/decade near the theoretical Nernstian one,with a wide linear working range from 6.0×10~(-8) to 1.0×10~(-3) mol/L.The fabricated electrode should be used in pH 2-4,response time of which was less than 200 s when the concentration of tetracycline was higher than 1.0×10~(-6) mol/L and no more than 30 min at the concentration of 1.0×10~(-8) mol/L.     

Emittance-exchange-based high harmonic generation scheme for a short-wavelength free electron laser

Generation of short-wavelength radiation by a free-electron laser using up-frequency conversion of an electron bunch density modulation is currently an area of active research. We propose a new scheme for producing the longitudinal electron bunch density modulation similar to the recently proposed echo-enabled harmonic generation but based on an emittance exchange beam line and a multislit mask. Beam line analysis and start-to-end simulation are presented.     

Tuning the metal-insulator transition in manganite films through surface exchange coupling with magnetic nanodots

In strongly correlated electronic systems, the global transport behavior depends sensitively on spin ordering. We show that spin ordering in manganites can be controlled by depositing isolated ferromagnetic nanodots at the surface. The exchange field at the interface is tunable with nanodot density and makes it possible to overcome dimensionality and strain effects in frustrated systems to greatly increasing the metal-insulator transition and magnetoresistance. These findings indicate that electronic phase separation can be controlled by the presence of magnetic nanodots.     

化学计量学方法在三维荧光光谱分析中的应用

随着分析数据日益复杂,传统的用于光谱分析中的数据处理方法已不能满足分析需要,而化学计量学应用数学、统计学以及计算机等科学的方法与手段,设计和选择最优的量测方法,并通过对数据的解析,可最大限度的获取光谱数据中的有用信息.本文首先介绍了几类常用化学计量学方法分析的三维荧光光谱,其次介绍了常用于光谱分析的化学计量学方法,如统...     

A novel fringe adaptation method for digital projector

Aimed to obtain high-quality sinusoidal fringe projection, a new method to correct the output fringe of digital projector is presented. The method is based on the proposed fringe transform model, which describes the relationship of the input and output fringe pattern. Firstly, a series of fringe patterns are projected and from the fringe images, the transform function is calculated by the pattern shifting method. At last, by modifying the input fringe pattern, a standard sinusoidal output fringe can be achieved. Different from the previous methods, the waveform nonlinearity is estimated by varying the intensity of the projected fringe pixel by pixel; thus the waveform nonlinearity can be estimated precisely and the time cost is considerably reduced. Experimental results show that by modification of the input projection patterns the projector can project fringe with high-quality sinusoidal waveform leading to high performance of the projection system.     

Vertex‐Transitive Cubic Graphs of Square‐Free Order

A classification of connected vertex‐transitive cubic graphs of square‐free order is provided. It is shown that such graphs are well‐characterized metacirculants (including dihedrants, generalized Petersen graphs, Möbius bands), or Tutte's 8‐cage, or graphs arisen from simple groups PSL(2, p).     

Ni(OAc)2: a highly efficient catalyst for the synthesis of enaminone and enamino ester derivatives under solvent‐free conditions

Ni(OAc)₂ was found to be an efficient catalyst for the synthesis of β‐enamino ketones or esters from β‐dicarbonyl compounds and amines under solvent‐free conditions. The reusability of the catalyst was successfully examined without noticeable loss of its catalytic activity. Copyright © 2010 John Wiley & Sons, Ltd.     

Simultaneous determination of phthalates and adipates in human serum using gas chromatography–mass spectrometry with solid‐phase extraction

A gas chromatography–mass spectrometry assay was developed and validated for the simultaneous determination of phthalates and adipates in human serum. The phthalates and adipates studied were dimethyl phthalate, diethyl phthalate, dibutyl phthalate, benzylbutyl phthalate, di‐2‐ethylhexyl phthalate, di‐n‐octyl phthalate, diethyl adipate, dibutyl adipate, diisobutyl adipate, bis(2‐butoxyethyl) adipate and di‐2‐ethylhexyl adipate, with diisooctyl phthalate as internal standard. The extraction and cleaning up procedure was carried out with solid‐phase extraction cartridges containing dimethyl butylamine groups, which showed extraction efficiencies over 88% for each analyte and the internal standard. The calibration curves obtained were linear with correlation coefficients greater than 0.98. For all analytes, the assay gave CV% values for intra‐day precision from 4.9 to 13.3% and mean accuracy values from 91.4 to 108.4%, while inter‐day precision was 5.2–13.4% and mean accuracy 91.0–110.2%. The limits of detection for the assay of phthalates and adipates were in the range 0.7–4.5 ng/mL. The method is simple, sensitive and accurate, and allows for simultaneous determination of nanogram levels of phthalates and adipates in human serum. It was successfully applied to an investigation on the level of phthalates and adipates in a non‐occupationally exposed population.     

磷光光度法在药物分析中的应用

本文评述了固体基质室温磷光，流体介质室温磷光，低温磷光和室温磷光传感器在药物分析中的应用，涉及到的药物有生物碱，中草药有效成分，四环素类，喹喏酮类，维生素B2，抗癌药物，萘唑啉，萘普生和血管扩张剂潘生丁双嘧哌胺醇等，在药物分析中，固体基质室温磷光取样量只有微升级，操作快，成本低，流体室温磷光结合流动注射和化学传感技术，在药物的快速连续在线监测方面优势明显，而经过改善的低温磷体室温磷光结合流动注射和化学传感技术，在药物的快速连续在线监测方面优势明显，而经过改善的低温磷光方法，除了克服操作方面的某些弱点外，仍然保持高灵敏度的特点，随着敏化和猝死发光，能量转移，衍生发光和免疫发光等技术的发展，磷光方法在药物分析中的应用将会更加广泛。     

WAY TO DETERMINE STIFFNESS FUNCTION OF STRUCTURE

For calculating the stiffness function of a structure, the differential equation of the vibration of the structure was divided into the differential equation on the original stiffness function that was known, and Fredholm integral equation of the first kind on the undetermined stiffness function that was unknown. And the stable solutions of the integral equation, when the smooth factor was equal to zero, was solved by the extrapolation with p smooth factors. So the stiffness function of the structure is obtained. Applied examples show that the method is feasible and effective.