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991.
The theory of transmission fluctuation spectrometry (TFS) was recently developed for particle size analysis in dilute flowing particle suspensions, whereby the statistical transmission fluctuations are used to extract the particle size distribution and particle concentration. 相似文献
992.
Ken Hosoya Hiroshi Aoki Takuya Kubo Masashi Teramachi Nobuo Tanaka Jun Haginaka 《Journal of polymer science. Part A, Polymer chemistry》2005,43(12):2556-2566
Highly crosslinked polymer networks were characterized in terms of structural differences based on the crosslinked network structures with their chromatographic molecular retentivity for some polyaromatic hydrocarbons (PAHs). Because PAHs and some sterically bulky solutes were used in the chromatographic characterization, tiny differences in the crosslinked polymer networks were observed in terms of the chromatographic molecular retentivity. Ethylene dimethacrylate afforded molecular retentivity for anthracene, and this recognition ability changed with the polymerization time. In addition, 1,4‐butanediol dimethacrylate afforded molecular retentivity for pyrene, and this retentivity was larger than that for anthracene. The polymerization methods also affected the resulting polymer networks drastically. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2556–2566, 2005 相似文献
993.
NiMn2O4纳米粉体的相变过程和晶粒生长行为研究 总被引:1,自引:0,他引:1
王疆瑛 《新疆大学学报(理工版)》1998,15(2):49-51
采用溶胶凝胶法(Sol-Gel)制备NiMn2O4纳米粉体.用X射线衍射(XRD)法,热分析仪研究NiMn2O4纳米粉体的相变过程.用X射线衍射线线宽法,透射电子显微镜(TEM)研究晶粒长大行为.研究结果表明:热处理温度小于670°C,存在非晶晶化过程和向NiMn2O4尖晶石主晶相转变等相变过程,晶粒尺寸缓慢增大,热处理温度在于670°C,粉体的相结构为NiMn2O4尖晶石相.晶粒尺寸较快增长.相变过程严重影响了晶粒长大行为. 相似文献
994.
利用电化学阳极腐蚀的方法制备了多孔硅膜,实验发现多孔硅膜为多层结构,表面层为纳米结构,其余为微米结构,多孔硅的物理及化学结构的研究表明多孔硅是一种表面上含硅、氧、氢、氟元素组成的化合物包覆着的纳米晶硅粒和微米硅丝.多孔硅的发光主要来自表面纳米结构层,亚微米结构层并未见发光,从实验上证实了多孔硅的发光与量子尺寸效应紧密关联. 相似文献
995.
Guang‐Hui Ma Junichiro Fujiwara Zhi‐Guo Su Shinzo Omi 《Journal of polymer science. Part A, Polymer chemistry》2003,41(16):2588-2598
A highly crosslinked poly(styrene–divinyl benzene–trimethyolpropane trimethacrylate) microsphere containing a polyimide prepolymer (PIP) was prepared by a new emulsification method, Shirasu porous glass (SPG) membrane emulsification, and a subsequent radical suspension polymerization. That is, a mixture of styrene, divinyl benzene, trimethyol propane trimethacrylate (TMPTMA), and PIP containing an initiator was permeated through the uniform pores of the SPG membrane into a continuous phase containing a stabilizer to form uniform droplets. Then, the suspension polymerization was carried out at 65 °C for 24 h. The trifunctional crosslinker TMPTMA was added to enhance the destructive strength of the microsphere, and PIP was incorporated into the microsphere to provide an adhesion force by a known self‐curing reaction at 220 °C. The effects of the feed amounts of TMPTMA and PIP on the monomer conversion, size distribution, and destructive strength of the microsphere were investigated. The monomer conversion increased with an increase in TMPTMA. The particle size distribution became narrower as the TMPTMA feed amount increased, but it became broader with an increase in PIP. The destructive strength increased with increases in TMPTMA and PIP. After a heat treatment at 220 °C, the destructive strength decreased because of the heat degradation of the polymer. The addition of TMPTMA suppressed the heat degradation, and PIP could undergo self‐curing at 220 °C. The obtained highly crosslinked uniform microsphere containing PIP has potential applications in liquid‐crystal displays. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2588–2598, 2003 相似文献
996.
朱文辉 《数学的实践与认识》2007,37(14):171-176
为了发掘节省原料的潜力,对销量很大的饮料易拉罐进行优化设计.建立起具有通用性的优化模型;运用压缩变量技术,解决了模型复杂不易求解的困难;给出了便于实施计算的一整套显式求解公式.通过方向导数分析和流动极值分析,证明了解的最优性,指出了目标函数的退化特征及其临界状态;结合数学理论分析、具体数值计算和实际工艺条件,形成了层层递进式的优化设计途径. 相似文献
998.
999.
Montserrat Filella Jingwu Zhang Meredith E. Newman Jacques Buffle 《Colloids and surfaces. A, Physicochemical and engineering aspects》1997,120(1-3):27-46
Particles are ubiquitous in all natural systems and play an important role in the control and fate of nutrients and pollutants. Currently, only limited information is available concerning particle number and size distributions, owing to the problems involved in their experimental determination. In the present paper, limitations and optimal conditions for particle size determinations of environmental samples using photon correlation spectroscopy are studied. The detection limit, the effects of polydispersity of the sample and the refractive index value are discussed based on results obtained with synthetic colloids. The photon correlation spectroscopic determination of particle size distributions in real aquatic systems is also presented in the second part of the paper. 相似文献
1000.
We classify open maximal subalgebras of all infinite-dimensional linearly compact simple Lie superalgebras. This is applied to the classification of infinite-dimensional Lie superalgebras of vector fields, acting transitively and primitively in a formal neighborhood of a point of a finite-dimensional supermanifold. 相似文献