Pb1-xSrxTiO3 (0≤x≤0.9) thin films on Si (100) substrate were prepared by the sol-gel process and their characteristics were investigated as a function of strontium content(x). With increasing of the strontium ...Pb1-xSrxTiO3 (0≤x≤0.9) thin films on Si (100) substrate were prepared by the sol-gel process and their characteristics were investigated as a function of strontium content(x). With increasing of the strontium content, the tetragonality (c/a) was slightly decreased, the splitting peaks become less prominent and the splitting peaks tend to merge into a single peak. Furthermore, the grain size of the films was systematically reduced with the increase in strontium content.展开更多
The present paper develops the scaling theory of polyelectrolyte nanogels in dilute and semidilute solutions. The dependencies of the nanogel dimension on branching topology, charge fraction, subchain length, segment ...The present paper develops the scaling theory of polyelectrolyte nanogels in dilute and semidilute solutions. The dependencies of the nanogel dimension on branching topology, charge fraction, subchain length, segment number, solution concentration are obtained. For a single polyeleetrolyte nanogel in salt free solution, the nanogel may be swelled by the Coulombie repulsion (the so-called polyelectrolyte regime) or the osmotic eounterion pressure (the so-called osmotic regime). Characteristics and boundaries between different regimes of a single polyelectrolyte nanogel are summarized. In dilute solution, the nanogels in polyeleetrolyte regime will distribute orderly with the increase of concentration. While the nanogels in osmotic regime will always distribute randomly. Different concentration dependencies of the size of a nanogel in polyeleetrolyte regime and in osmotic regime are also explored.展开更多
文摘Pb1-xSrxTiO3 (0≤x≤0.9) thin films on Si (100) substrate were prepared by the sol-gel process and their characteristics were investigated as a function of strontium content(x). With increasing of the strontium content, the tetragonality (c/a) was slightly decreased, the splitting peaks become less prominent and the splitting peaks tend to merge into a single peak. Furthermore, the grain size of the films was systematically reduced with the increase in strontium content.
基金Supported by China Earthquake Administration under Grant No.20150112National Natural Science Foundation of China under Grant No.21504014
文摘The present paper develops the scaling theory of polyelectrolyte nanogels in dilute and semidilute solutions. The dependencies of the nanogel dimension on branching topology, charge fraction, subchain length, segment number, solution concentration are obtained. For a single polyeleetrolyte nanogel in salt free solution, the nanogel may be swelled by the Coulombie repulsion (the so-called polyelectrolyte regime) or the osmotic eounterion pressure (the so-called osmotic regime). Characteristics and boundaries between different regimes of a single polyelectrolyte nanogel are summarized. In dilute solution, the nanogels in polyeleetrolyte regime will distribute orderly with the increase of concentration. While the nanogels in osmotic regime will always distribute randomly. Different concentration dependencies of the size of a nanogel in polyeleetrolyte regime and in osmotic regime are also explored.