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Liang Hu Fan Yang Chaocan Zhang Yuanyuan Hu Yanjun Chen 《Colloid and polymer science》2011,289(3):323-331
In this work, a functional gradient polymeric material derived from silicon-containing acrylate blend emulsion film is prepared
in two steps. Firstly, 3-[tris(trimethylsilyloxy)silyl] propyl methacrylate (TRIS)-modified acrylate latex is prepared using
multiple emulsifiers by the two-stage semicontinuous emulsion copolymerization method. Next, blend latexes composed of TRIS-containing
and TRIS-free acrylate latexes are obtained. Detailed studies on the effects of the film-formation temperature and the glass
transition temperature (T
g) differences on the compositional gradient film are conducted. Surface energy analysis shows that silicon elements enriched
at the film-air (F-A) interface and T
g differences facilitate the fabrication of silicon gradient in emulsion blend films. Scanning electron microscopy-energy dispersive
X-ray further reveals that the concentration of silicon components varies in a gradient-like manner along the overall transaction
of the film when the film-formation temperature is 55 °C. However, excessive temperature creates the formation of a segmental
gradient distribution of silicon in the emulsion blend films. 相似文献
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Determination of the surface states from the ultrafast electronic states in a thermoelectric material 下载免费PDF全文
We reveal the electronic structure in Yb Cd2Sb2,a thermoelectric material,by angle-resolved photoemission spectroscopy(ARPES)and time-resolved ARPES(tr ARPES).Specifically,three bulk bands at the vicinity of the Fermi level are evidenced near the Brillouin zone center,consistent with the density functional theory(DFT)calculation.It is interesting that the spin-unpolarized bulk bands respond unexpectedly to right-and left-handed circularly polarized probe.In addition,a hole band of surface states,which is not sensitive to the polarization of the probe beam and is not expected from the DFT calculation,is identified.We find that the non-equilibrium quasiparticle recovery rate is much smaller in the surface states than that of the bulk states.Our results demonstrate that the surface states can be distinguished from the bulk ones from a view of time scale in the nonequilibrium physics. 相似文献
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Inside Cover: Synthesis and Characterization of Carbazole‐Linked Porphyrin Tweezers (Chem. Eur. J. 34/2015) 下载免费PDF全文
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Xiuyan Wan Hui Zhong Wei Pan Yanhua Li Yuanyuan Chen Na Li Bo Tang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(40):14272-14277
Dihydroartemisinin (DHA) has attracted increasing attention as an anticancer agent. However, using DHA to treat cancer usually depends on the synergistic effects of exogenous components, and the loss of DHA during delivery reduces its effectiveness in cancer therapy. Reported herein is a programmed release nanoplatform of DHA to synergistically treat cancer with a Fe‐TCPP [(4,4,4,4‐(porphine‐5,10,15,20‐tetrayl) tetrakis(benzoic acid)] NMOF (nanoscale MOF) having a CaCO3 mineralized coating, which prevents DHA leakage during transport in the bloodstream. When the nanoplatform arrives at the tumor site, the weakly acidic microenvironment and high concentration of glutathione (GSH) trigger DHA release and TCPP activation, enabling the synergistic Fe2+‐DHA‐mediated chemodynamic therapy, Ca2+‐DHA‐mediated oncosis therapy, and TCPP‐mediated photodynamic therapy. In vivo experiments demonstrated that the nanoplatform showed enhanced anticancer efficiency and negligible toxicity. 相似文献