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941.
Meihan Dan Fei Huo Xu Zhang Xiaohui Wang Wangqing Zhang 《Journal of polymer science. Part A, Polymer chemistry》2013,51(7):1573-1584
The dispersion reversible addition‐fragmentation chain transfer (RAFT) polymerization of 4‐vinylpyridine in toluene in the presence of the polystyrene dithiobenzoate (PS‐CTA) macro‐RAFT agent with different chain length is discussed. The RAFT polymerization undergoes an initial slow homogeneous polymerization and a subsequent fast heterogeneous one. The RAFT polymerization rate is dependent on the PS‐CTA chain length, and short PS‐CTA generally leads to fast RAFT polymerization. The dispersion RAFT polymerization induces the self‐assembly of the in situ synthesized polystyrene‐b‐poly(4‐vinylpyridine) block copolymer into highly concentrated block copolymer nano‐objects. The PS‐CTA chain length exerts great influence on the particle nucleation and the size and morphology of the block copolymer nano‐objects. It is found, short PS‐CTA leads to fast particle nucleation and tends to produce large‐sized vesicles or large‐compound micelles, and long PS‐CTA leads to formation of small‐sized nanospheres. Comparison between the polymerization‐induced self‐assembly and self‐assembly of block copolymer in the block‐selective solvent is made, and the great difference between the two methods is demonstrated. The present study is anticipated to be useful to reveal the chain extension and the particle growth of block copolymer during the RAFT polymerization under dispersion condition. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
942.
Xing-Wu Liu Chun-Fang Huo Yong-Wang Li Jianguo Wang Haijun Jiao 《Surface science》2012,606(7-8):733-739
Spin-polarized density functional theory calculations have been performed to investigate carbon deposition and carbide formation on Fe(100) and Fe(110) at different carbon coverage. On Fe(100) with increasing carbon coverage, the most stable carbon adsorption configuration changes from surface carbon adsorption to surface carbon diffusion into subsurface, and surface carbon clustering is not favored thermodynamically. However, surface carbon clustering is more favored kinetically than carbon diffusion; and carbon diffusion into subsurface and surface carbon clustering become competitive. On Fe(110) with increasing surface carbon coverage, the most stable adsorption configuration changes from surface carbon adsorption to surface carbon diffusion into subsurface, and this process is favored both kinetically and thermodynamically, and surface carbon clustering is neither favored nor competitive. Surface carbon deposition might form on Fe(100), while carbide formation might be found on Fe(110). 相似文献
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Huo Bianbian Chen Mingli Chen Junjie Li Yuanyuan Zhang Wanjun Wang Jianhua Qin Weijie Qian Xiaohong 《Analytical and bioanalytical chemistry》2018,410(28):7305-7312
Analytical and Bioanalytical Chemistry - Urine is an attractive and non-invasive alternative source to tissue, blood or other biofluids for biomarker screening in clinical research. In normal human... 相似文献
949.
The moment of inertia of the proto neutron star PSR J0348+0432 is studied in the framework of relativistic mean field theory under neutrino trapped. We find that the temperature of the PNS PSR J0348+0432 increases with the increase of the baryon number density and at the center of the star it is in the range Tc = 41.662–45.685 MeV. Corresponding to the observation mass 1.97–2.05 M⊙, the radius of the NS PSR J0348+0432 is in the range 12.948–12.16 km whereas that of the PNS PSR J0348+0432 is in the range 14.46–13.561 km. The radius of the PNS PSR J0348+0432 has increased by 11.7%–11.5% compared with that of the NS PSR J0348+0432. The central moment of inertia of the PNS PSR J0348+0432 is in the range 2.207?×?1045–1.914?×?1045 g cm2 whereas that of the NS PSR J0348+0432 is only in the range 1.9?×?1045–1.552?×?1045 g cm2. Compared with the moment of inertia of the NS PSR J0348+0432, the central moment of inertia of the PNS PSR J0348+0432 increases by 16%–23%. 相似文献
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Metabolic profiling of luteolin‐7‐O‐glucoside in rat urine,plasma, bile and feces after oral administration using ultra‐high‐performance liquid chromatography/quadrupole time‐of‐flight mass spectrometry
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