Synthesis of TiO2–SiO2/polymer core–shell microspheres with a microphase‐inversion method

A novel microphase‐inversion method was proposed for the preparation of TiO₂–SiO₂/poly(methyl methacrylate) core–shell nanocomposite particles. The inorganic–polymer nanocomposites were first synthesized via a free‐radical copolymerization in a tetrahydrofuran solution, and the poor solvent was added slowly to induce the microphase separation of the nanocomposite and result in the formation of nanoparticles. The average particle sizes of the microspheres ranged from 70 to 1000 nm, depending on the reaction conditions. Transmission electron microscopy and scanning electron microscopy indicated a core–shell morphology for the obtained microspheres. Thermogravimetric analysis and X‐ray photoelectron spectroscopy measurements confirmed that the surface of the nanocomposite microspheres was polymer‐rich, and this was consistent with the core–shell morphology. The influence of the synthetic conditions, such as the inorganic composition and the content of the crosslinking monomer, on the particle properties was studied in detail. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3911–3920, 2006     

Effect of glass bead packing on the fibrillation of liquid‐crystalline polymer in polycarbonate

Polycarbonate (PC) was melt blended with small amount of liquid‐crystalline polymer (LCP) and various contents of glass beads (GB) having different diameters. The rheological measurements indicated that the GB addition increased the viscosity ratio and seemed unfavorable to the LCP fibrillation. However, the morphological observation showed that the LCP fibrillation was promoted by the GB addition and varied with the GB packing. With the increased GB packing by increasing the GB content and/or decreasing the GB diameter, LCP deformed from spheres and ellipsoids into stretched ellipsoids at lower shear rates and into long fibrils at higher shear rates. Although higher content of smaller GB jammed into the larger LCP droplets and inhibited the LCP fibrillation, very long LCP fibrils formed at higher shear rates at a high enough packing of GB. The relationship between GB packing and LCP fibrillation revealed two kinds of hydrodynamic effects of GB promoting the LCP fibrillation: at lower GB packing, the shear flow was enhanced by the high local shear between GB, in quantity; and for a high enough GB packing, the shear flow was changed, in quality, into elongational flow, which was more effective for the LCP fibrillation. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1020–1030, 2006     

The Micro-Theory of Ultra-Short Pulse Propagating in Nonlinear Fiber

The modified quantum nonlinear Schrodinger equation of ultra-short pulse propagating in fiber is derived using dispersion relation and the Hamiltonian of the transmission system. The derived equation is solved with linearization approximation, and modulation instability is analyzed. The equation is also solved with Hartree approximation. The results indicate that pulse power, loss and self-steeping effect change the critical frequency, the maximum gain and the gain spectrum range, but the third order dispersion has no effect on modulation instability. The expectation value of optical field is average of a set of modified classical solitons, and higher order terms change the amplitude, pulse position and phase of soliton.     

仲态电子偶素湮没辐射能量的改进测量

用充氧气的气凝硅胶作仲态电子偶素源,用¹⁹²Ir精密γ能量作标准,以时间选择能谱仪和滑动比较法改进测量仲态电子偶素2γ湮没能量,得到hv=510995.34±0.69eV.经电子偶素结合能修正,得正、负电子对静止质量,与电子质量比较,表明正、负电子质量在1.4ppm内一致.     

Interaction of gravitational waves with a superconducting cylindrical antenna

In this paper we investigate the effects of gravitational waves (GW) on a superconducting cylindrical antenna (S-antenna). We suggest that the electric fields induced by GW of dimensionless amplitudeh - 10^–24 in the interior of existing cylindrical antenna might be detectable.     

后处理温度对ZrO2气凝胶超细粉织构和结构的影响

运用神效儿宝治疗小儿厌食症２１０例，总有效率为９５．２％，显效率为６２．４％。该药使用、携带方便、见效快，疗效短，无毒副作用。实验证明，该药能显著提高胃蛋白酶含量，减慢肠管推进性运动，提高动物耐疲劳、耐缺氧能力，提高巨噬细胞吞噬率及血清补Ｃ３含量，且无毒副。作用     

聚乙烯单晶的退火效应

用混合晶红外光谱法和ＳＡＸＳ、ＤＳＣ和ＬＡＭ等方法研究了聚乙烯单晶在７５℃、９０℃和１０５℃退火前后的结构变化，发现在９０℃以下和１０５℃以上退火，遵循不同的退火机制     

A Novel Organic—Inorganic Complex：Synthesis and Crystal Structure of [Ca（DMSO）5（H2O）]2 SiMo12O40

It is becoming a focus to synthesize and assemble organic-inorganic materials, especially, to synthesize charge-transfer complexes formed by polyoxometalate and organic donors. They have attracted much attention because such complexes are active in their electric, magnetic and optic properties1-4, many investigations about them have been done and some crystal structures of them were reported5-6. But, the disadvantage of these crystals is instability at room temperature. According to the view…     

软珊瑚Sinularia sp.中次生代谢产物的结构鉴定

细胞毒性;软珊瑚Sinularia sp.中次生代谢产物的结构鉴定