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DS Zhulai SA Bugaychuk GV Klimusheva TA Mirnaya VN Asaula VI Handziuk 《Liquid crystals》2017,44(8):1269-1276
The class of thermotropic ionic liquid crystals (LCs) of the metal alkanoates possesses a number of unique properties, such as intrinsic ionic conductivity, high dissolving ability and ability to form time-stable mesomorphic glasses. These ionic LCs can be used as nanoreactors for the synthesis and stabilisation of different types of nanoparticles (NPs). Thus, some semiconductors, metals and core/shell NPs were chemically synthesised in the thermotropic ionic liquid crystalline phase (smectic A) of the cadmium octanoate (CdC8) and of the cobalt octanoate (CoC8). By applying the scanning electron microscopy, the cadmium and cobalt octanoate composites containing CdS, Au, Ag and core/shell Au/CdS NPs have been studied. NPs’ sizes and dispersion distribution of the NPs’ size in the nanocomposites have been obtained. 相似文献
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Alexander Fabricant Nikolai Kutev Tsviatko Rangelov 《Central European Journal of Mathematics》2013,11(9):1689-1697
A Hardy-type inequality with singular kernels at zero and on the boundary ?Ω is proved. Sharpness of the inequality is obtained for Ω= B 1(0). 相似文献
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S. L. Koontz R. V. Devivar W. J. Peltier J. E. Pearson T. A. Guillory J. D. Fabricant 《Colloid and polymer science》1999,277(6):557-562
We report synthesis and characterization of a macroporous polymeric material containing a covalently immobilized pore-surface
phase of well-defined thickness, gel-phase porosity and organic functional group content. The pore surfaces of otherwise inert
macroporous (32 μm mean pore size) ultrahigh-molecular-weight polyethylene (UHMWPE) are aminated throughout using a low-pressure
flowing-discharge process to enable covalent immobilization of lightly cross-linked polymer colloid particles on all pore
surfaces in the monolith. Solvent swelling and chemical derivitization of the covalently immobilized polymer colloid particles
produce a pore-surface gel phase of well-defined thickness, organic amine content, and gel-phase porosity. The low degree
of cross-linking in the polymer colloid particles prevents dissolution of the immobilized colloid in good solvents and enables
the formation of pore-surface gel phases having high gel porosity on swelling in good solvents. The pore-surface amination
introduced by the flowing discharge process varies by less than 17% through 5-mm thickness of the macroporous UHMWPE material.
The properties of the pore-surface gel phase also vary by less than 17% through the cross section. The pore-surface immobilized
polymer colloid particles swell by a factor of 10 in water and tetrahydrofuran after derivitization with polyethylene glycol.
Received: 20 November 1998 Accepted in revised form: 21 January 1999 相似文献
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S. L. Koontz W. J. Peltier J. E. Pearson J. D. Fabricant 《Colloid and polymer science》1999,277(11):1065-1071
Covalently immobilized pore-surface gel phases were prepared in a functionalized macroporous ultra-high-molecular-weight
polyethylene by covalent coupling of lightly cross-linked polymer colloid particles [50% styrene, 49.8% (chloromethyl)stryrene,
0.2% divinylbenzene] to the interstitial pore surfaces. Swelling the covalently coupled colloid particles in a good solvent
followed by chemical derivitization resulted in an immobilized pore-surface gel phase rich in primary amine groups. The macromolecular
reactivity and molecular size-exclusion characteristics of the aminated pore-surface gel phase were then determined using
monofunctional, amine-reactive, poly (ethylene glycol)s (PEG). Pegylated pore-surface gel phases that ranged from 71% (10,000
molecular weight PEG) to 56% (40,000 molecular weight PEG) PEG by weight resulted from reaction of the aminated gel phase
with the PEG probe molecules. The number of PEG molecules reacting with the aminated pore-surface gel phase depends only on
the Flory radius (or radius of gyration) of the PEG molecule to the negative 2.49th power i.e., 1/R
f
2.49, corresponding to a M−1.48 dependence. The immobilized and pegylated polymer colloid particles swell by a factor of 16–25 times the diameter of the
original polymer colloid particles in water, thereby demonstrating that pegylation occurred though a substantial fraction
of the volume of the immobilized colloid particles.
Received: 18 January 1999 Accepted in revised form: 8 June 1999 相似文献