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An indirect laser photoacoustic technique is described. The basic principle, the experimental set-up and the influencing factors are discussed in detail. This method was used to quantify phenylamine, arginine and methylene blue on membranes. The linear ranges of the calibration curve are up to two orders of magnitude. With 1 microliter of sample solution, the detection limits are 0.25, 1.52 and 0.14 pmol for phenylamine, arginine and methylene blue, respectively. 相似文献
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105.
Xiao-pingYan Bao-linHe JieZhang Han-fanLiua 《高分子科学》2005,(4):393-399
Modification of transition metal cations to polymer-stabilized Pt colloidal clusters modified with cinchonidine was studied in enantioselective hydrogenation of methyl pyruvate. Compared to the enantiomeric excess (e.e.) value (71.4%) obtained without the presence of metal cations, obvious e.e. enhancement (up to 82.5%) was resulted from the addition of Zn^2 but with a certain decrease in activity. The reaction parameters in the presence of Zn^2 were also studied. It was found that the Pt colloidal catalysts in the presence of metal cations performed very differently from that in the absence of metal cations. 相似文献
106.
Molecularly imprinted polymer membranes containing artificial recognition sites for 4-aminopyridine have been prepared by photopolymerization using 4-aminopyridine as template. Reference membranes were prepared with the same monomer mixture but in the absence of the template. The binding characteristics of the imprinted polymer membrane were investigated by a batch method and the transport properties of the membranes were investigated using diffusion chambers. The results showed that the binding amount of 4-aminopyridine is higher than that of 2-aminopyridine whereas the latter can transport the 4-aminopyridine imprinted polymer membrane faster than 4-aminopyridine. 相似文献
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108.
A method is proposed to calculate molar conductivity based on mode coupling theory in which the ion transference number is introduced into the theory. The molar conductivities of LiPF6, LiClO4, LiBF4, LiAsF6 in PC (propylene carbonate) are calculated based on this method. The results fit well to the literature data. This presents a potential way to calculate the conductivities of Li-ion battery electrolytes. 相似文献
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