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A 2-dimensional gradual period photonic heterostructure was made with holography by use of non-uniform swelling effect of dichromated gelatin during processing. In this structure, the symmetric point group of triangle lattice was debased to C2V from C6V. Theoretical analysis and experimental results show that omnidirectional band gap in visible range can be achieved with this kind of heterostructure made by low refractive index materials. 相似文献
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Xiongxin Dai Sheila Kramer-Tremblay 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(2):461-466
Assays of alpha- and beta-emitting radionuclides in swipe samples are often required to monitor the presence of removable
surface contamination for radiological protection and control in nuclear facilities. Swipe analysis has also proven to be
a very sensitive analytical technique to detect nuclear signatures for safeguard verification purposes. A new sequential method
for the determination of actinide isotopes and radiostrontium in swipe samples, which utilizes a streamlined column separation
with stacked anion and extraction chromatography resins, has been developed. To validate the separation procedure, spike and
blank samples were prepared and analyzed by inductively coupled mass spectrometry (ICP-MS), alpha spectrometry and liquid
scintillation (LS) counting. Low detection limits have been achieved for isotopic analysis of Pu (238Pu, 239Pu, 240Pu, 241Pu), U (234U, 235U, 238U), Am (241Am), Cm (242Cm, 243/244Cm) and Sr (90Sr) at ultra-trace concentration levels in swipe samples. 相似文献
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Based on the solvent-free method, novel fluorinated polyurethane/polyacrylate hybrid emulsions, dodecafluoroheptyl methacrylate (DFMA) as fluorinated monomer, were successfully prepared via emulsion polymerization without traditional emulsifier. For the purpose of increasing the grafting ratio of polyurethane and polyacrylate, 60Co γ-ray radiation polymerization had been adopted to enhance the hardness of latex film. The chain structure and polymerization progress were confirmed by the analysis of Fourier transform infrared spectroscopy. The grafting ratio of polymethyl methacrylate and polyurethane was obtained by calculating the ratio of N–H peak integral area and Ph(C=C) peak integral area. The effect of DFMA content on thermal stability, mechanical property and water resistance were investigated systematically by thermal weight loss analysis, tensile strength test, absorbed water ratio and water contact angle. 相似文献
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Na Guo Dawei Yang Keyume Ablajan Xiaohong Niu Bin Fan Zhiguo Wang Jingang Dai Xiaoxia Wu Baidong Liu 《Journal of separation science》2013,36(12):1953-1958
A rapid analytical method based on rapid resolution LC coupled with MS/MS was first established to quantify seven alkaloids in processed Fuzi decoction. The chromatographic method was optimized to allow simultaneous analysis of all analytes in 5 min and demonstrated good linearity (r > 0.9995), repeatability (RSD < 4.36%), intra‐ and interday precisions (RSD < 5.07%) with good accuracies (97.76–105.08%) and good recovery (95.0–107.5%) of seven alkaloids, namely higenamine, benzoylhypaconine, benzoylmesaconine, benzoylaconine, aconitine, hypaconitine, and mesaconitine. The LODs for these markers were in the range of 2.30–17.00 pg/mL. Quantitative analysis of the seven alkaloids in Baifupian decoction and Heishunpian decoction showed that the content of the seven marker chemicals varied significantly and concluded that the quality of Fuzi was greatly affected by different processed methods. The developed method could be used as a rapid, sensitive, and reliable approach for assessment of the quality of processed Fuzi and related decoction. 相似文献