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41.
Electropolymerized m-phenylenediamine was used as an active coating for immobilizing urease and lectin on a gold-plated thickness-shear-mode (TSM) crystal. To enhance effectiveness of immobilization. a bilayer polymer film composed of polyaniline and poly-m-phenylenediamine was proposed. Compared with single poly-m-phenylenediamine film, the bilayer polymer film gave better results in terms of immobilizing capacity, stability and reproductivity. On this bilayer-film-coated TSM quartz crystal, the amount of immobilized lectin was estimated about 1.8 mug/cm(2). Detection of purified human erythrocytes is demonstrated as an example of potential application of this lectin-modified TSM biosensor in clinic. 相似文献
42.
含吲哚核端基多甲川菁染料的合成及性能 总被引:6,自引:0,他引:6
我们曾合成了具有桥环的硫三碳菁及多甲川苯乙烯菁,并测定了光学性能。本文报道吲哚环为端基的桥链三碳菁和四甲川苯乙烯菁的合成及在有机溶剂中电子吸收光谱及溶解性能的测定。所用仪器同前,7种多甲川菁染料的合成反应如下: 相似文献
43.
44.
Two pentacene derivatives 1 and 2 were synthesized from the Diels-Alder reactions of furan derivatives with 1,4-benzoquinone. They were characterized by the
methods of 1H — nuclear magnetic resonance spectroscopy (1H-NMR), matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS), ultraviolet and visible
spectrophotometry (UV-VIS), photoluminescence (PL) spectrometry and cyclic voltammetry (CV). The energy gaps of 1 and 2, taken directly from spectroscopic measurements, are broad as 2.72 and 2.46 eV, leading to blue and greenish blue photoluminescence,
respectively. The LUMO and HOMO energy levels are −2.77 and −5.49 eV for 1, and −2.91 and −5.37 eV for 2, respectively. The low energy levels make both 1 and 2 good air-stabilities and promising n-type semiconductor candidates for use in organic electronics. 相似文献
45.
46.
Liang Oyang Hao-Ling Sun Xin-Yi Wang Jun-Ran Li Dao-Bo Nie Wen-Fu Fu Song Gao Kai-Bei Yu 《Journal of Molecular Structure》2005,740(1-3):175-180
Ternary terbium complexes with p-aminobenzoic acid (HL), [TbL3(DMSO)(H2O)]2 (1), [TbL3(DMF)(H2O)]2 (2) and [TbL3(Bpy)(H2O)]2·2H2O (3) (DMSO=dimethyl sulfoxide, DMF=N, N- dimethylformamide, Bpy=2, 2′- bipyridyl) have been synthesized, and their crystal structures determined. The luminescence properties of these complexes, including both the emission quantum yield and the fluorescence lifetime, have been investigated. The effect of a second ligand on the crystal structure and luminescence property of the ternary terbium p-aminobenzoic acid complexes, and the relationship between luminescence properties and crystal structure, including coordination mode of the L− ligand and the characteristics of a second ligand, are discussed. 相似文献
47.
Based on the transmittance-averaged rather than absorbance-averaged model of long optical pathlength transmission spectroelectrochemistry, a reasonable theoretical model for potential-step electrodeposition and stripping process has been developed. It can accurately predict the stripping-chronoabsorptometric waveform with a peak absorbance with respect to the time rather than that with no peak but only a theoretical maximum absorbance at the initial stage of the stripping process. Cu(II) in NH(3) . H(2)ONH(4)Cl supporting electrolyte is utilized to verify the theory. With this anodic stripping spectroelectrochemical method, a detection limit of ca 0.01mM without stirring or ca 0.002mM under stirring during deposition can be achieved. An application in the analysis of copper in practical samples is presented. 相似文献
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49.
A non-linear regression model was derived for the simultaneous determination of the rate constant in alkaline hydrolysis of esters and the initial concentration of esters based on the linear relationship between the frequency response of the surface acoustic wave sensor system and the conductivity of the solution. The model was tested theoretically and experimentally with the methyl-, ethyl-, and n-propyl-acetate systems. The corresponding rate constants estimated at 25 degrees C are 0.147, 0.103 and 0.0671 respectively. 相似文献
50.
Alloyed semiconductor quantum dots: tuning the optical properties without changing the particle size 总被引:7,自引:0,他引:7
Alloyed semiconductor quantum dots (cadmium selenium telluride) with both homogeneous and gradient internal structures have been prepared to achieve continuous tuning of the optical properties without changing the particle size. Our results demonstrate that composition and internal structure are two important parameters that can be used to tune the optical and electronic properties of multicomponent, alloyed quantum dots. A surprising finding is a nonlinear relationship between the composition and the absorption/emission energies, leading to new properties not obtainable from the parent binary systems. With red-shifted light emission up to 850 nm and quantum yields up to 60%, this new class of alloyed quantum dots opens new possibilities in band gap engineering and in developing near-infrared fluorescent probes for in vivo molecular imaging and biomarker detection. 相似文献