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141.
The reaction of 3,3-dimethyl-7-nitro-3,4-dihydroisoquinoline 1 with m-chloroperbenzoic acid (m-CPBA) mainly yielded oxaziridine and nitrone, with their selectivities being dependent on the solvents. The reaction with 2.5 equivalents of m-CPBA gave small amounts of oxaziridines and hydroxamic acids as well as isolated O-acylhydroxamate compounds. 相似文献
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143.
S. Hamdi S. Ouni H. Chaker J. Rohlicek R. Ben Hassen 《Journal of solid state chemistry》2011,184(11):2897-2901
A new compound DySr5Ni2.4Cu0.6O12−δ has been prepared by sol gel method and annealed at 1473 K in 1 atm of Ar gas flow. The X-ray diffraction (XRD) is used for phase identification. The sample shows to adopt the K2NiF4-type structure based on tolerance factor calculation. XRD analysis using the Rietveld method was carried out and it was found that DySr5Ni2.4Cu0.6O12−δ (Dy0.33Sr1.67Ni0.8Cu0.2O4−δ′) compound crystallizes in tetragonal symmetry with space group I4/mmm (Z=2). The lattice parameters are found to be at room temperature a=3.7696(5) Å and c=12.3747(2) Å. The final reliability indices were: RB=5.219% and χ2=3.47. Four probe electrical resistivity measurements were performed versus temperature in the range 294–579 K. A semiconducting behaviour over the whole range of temperature, with a conductivity maximum of 0.4 S cm−1 is observed at 510 K. 相似文献
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145.
Shadi Ali Hassen Ahmed YeTong Yang Shuming Li Haobin Shi Linghui Qian Jing Zhang 《Journal of separation science》2023,46(13):2201057
The ability to extract peptides and proteins from biological samples with excellent reusability, high adsorption capacity, and great selectivity is essential in scientific research and medical applications. Inspired by the advantages of core-shell materials, we fabricated a core-shell material using amino-functionalized silica as the core. Benzene-1,3,5-tricarbaldehyde and 3,5-diaminobenzoic acid were used as model organic ligands to construct a shell coating by alternately reacting the two monomers on the surface of silica microspheres. The resultant material featured an outstanding capability for the adsorption of cationic peptides, most likely owing to its porous structure, a large number of carboxylic functional groups, and low mass-transfer resistance. The maximum saturated adsorption capacity reached 833.3 mg/g and the adsorption process took only 20 min. Under optimized adsorption conditions, the core-shell material was used to selectively adsorb cationic peptides from the tryptic digestive solution of lysozyme and bovine serum albumin, Specifically, the analysis results showed seven cationic peptides in the eluate and twenty anionic peptides in the supernatant, which indicates the efficient trap of most cationic peptides in the digestive solution. 相似文献