排序方式: 共有69条查询结果,搜索用时 15 毫秒
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Morelos A Albuquerque IF Bondar NF Carrigan R Chen D Cooper PS Lisheng D Denisov AS Dobrovolsky AV Dubbs T Endler AM Escobar CO Foucher M Golovtsov VL Gottschalk H Gouffon P Grachev VT Khanzadeev AV Kubantsev MA Kuropatkin NP Lach J Lang Pengfei Lebedenko VN Li Chengze Li Yunshan Luksys M Mahon JR McCliment E Newsom C Pommot Maia MC Samsonov VM Schegelsky VA Shi Huanzhang Smith VJ Fukun T Terentyev NK Timm S Tkatch II Uvarov LN Vorobyov AA Yan Jie Wenheng Z Zheng Shuchen Zhong Yuanyuan 《Physical review D: Particles and fields》1995,52(7):3777-3780
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Maria Cristina Paganini Valentina Brunella Mario Chiesa 《Magnetic resonance in chemistry : MRC》2012,50(9):615-619
Ultra high molecular weight polyethylene (UHMWPE) has been studied with different magnetic resonance techniques to elicit information on the nature and the location of radicals generated during high energy irradiation. Field swept electron paramagnetic resonance, pulsed Davies electron nuclear double resonance and hyperfine sublevel correlation spectroscopic measurements allowed extracting for the first time the full 1H hyperfine coupling tensors of the most abundant radical, i.e. a secondary alkyl radical and to ascertain the formation of allyl radicals in the first stages of the irradiation process. The 1H hyperfine coupling tensors are analogous to those reported for single crystal irradiated polyethylene, suggesting that radicals generated in UHMWPE are located in the crystalline region of the polymer. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Speltini A Merli D Dondi D Paganini G Profumo A 《Analytical and bioanalytical chemistry》2012,403(4):1157-1165
Amino-terminated alkyl MWCNTs (MWCNTs-R-NH2), synthesized by chemical modification of the nanotube skeleton by nucleophilic substitution with 2,2′-(ethylenedioxy)diethylamine,
were successfully used as stationary phases for gas chromatographic separation of esters and chloroaromatics. The presence
of alkyl chains with polar embedded groups made the functionalized MWCNTs (f-MWCNTs) a mixed-mode GC separation material able
to interact in different ways with the analytes. Compared with non-functionalized MWCNTs (nf-MWCNTs), MWCNTs-R-NH2 had higher selectivity, enhanced resolution, and optimum retention behaviour, and they were proved to perform better than
the commercial stationary phase Porapak QS (PQS), claimed to be suitable for similar applications. The so-prepared stationary
phase was used for analysis of a synthetic mixture containing different classes of analytes, viz. esters, ketones, alcohols,
alkanes, and aromatic hydrocarbons, and finally used for investigation of similar real matrices. In particular, the constituents
of a commercial paint thinner were determined by direct injection of the sample, with good reproducibility (inter-day precision
RSDs from 5 to 19%). Two unknown samples of commercial white spirit were also analysed for determination of the aromatic hydrocarbon
content, and their composition was profiled on the basis of the different compounds identified. 相似文献
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