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41.
We achieved preparation of co-continuous titania based monolithic materials using several organic polymer monoliths as pore templates. Firstly, the organic polymer monoliths that had well controlled structures were prepared, and filled the pores of polymer monolith with tetra-n-butyl titanate (titan monomer). The following hydrolysis of the titan monomer resulted in titanium dioxide. The polymer monolith was removed by calcination at elevated temperature. We carefully studied the utility of polymer monolithic template, filling method of the titan monomer, and calcination conditions to realize co-continuous titania monolith. In addition, by the change of domain size (size of a skeleton + size of through a pore) of template, we were able to control domain size of the resulting titania monoliths.  相似文献   
42.
Polypropylene-graft-poly(polyethylene glycol-methacrylate) (PP-g-P(PEGMA)), which is a hydrophobic-hydrophilic graft copolymer, was synthesized by a combination of an atom transfer radical polymerization (ATRP) of PEGMA with brominated polypropylene (PP-Br), which was synthesized from PP-OH prepared by metallocene-catalyzed copolymerization. Its structure was confirmed by 1H NMR and GPC analyses. Transmission electron microscope (TEM) micrographs of PP-g-P(PEGMA) revealed the nanometer level microphase-separation morphology between the PP segment and the P(PEGMA) segment. The obtained PP-g-P(PEGMA) showed water-absorbing property as well as thermostability.  相似文献   
43.
The carbon black/alumina gel composites were prepared by sol-gel reaction of aluminum isopropoxide in the presence of polymer-grafted carbon black. The electric resistance of the alumina gel composite from polymer-grafted carbon black was very sensitive to vapor of good solvent for grafted polymer on carbon black: the electric resistance of the alumina gel composite suddenly decreased in solvent vapor and returned to initial resistance when it was transferred into dry air. The effect of surface area and particle size of carbon black on the responsiveness was also investigated. In addition, the electric resistance of the alumina gel composite was found to respond to water and methanol in n-hexane and diethyl ether.  相似文献   
44.
Abstract— Of the two types of thermal‐stress processes for glass, i.e., surface scribing and full body cleavage, the latter is not presently applied in commercial manufacturing due to the technical difficulties, notwithstanding its various advantages. These difficulties, which were pointed out by Kondratenko and were refered to as size effect, consist of a reduced processing speed in a large glass plate and the positional inaccuracy when cleaving close to edges of a glass plate. The result of the investigation aimed to solve these problems, which can pave the way to the commercial application of full body cleavage in the manufacturing of flat‐panel‐display (FPD) devices, is reported.  相似文献   
45.
The Green's functions of a point dislocation, a concentrated moment, a normal point force, a couple moment, and a couple bending force applied to an infinite plate with an arbitrarily shaped hole under a displacement boundary condition are derived in this paper. The closed-form stress functions are obtained by using the technique of the rational mapping function and the complex stress function approach. In the derivation, the analytical continuation and Cauchy integral are used for the different actions. Without loss of generality, some calculated results are shown for a square hole under a fixed boundary. The solutions show that the stress functions have different orders of singularity for the different actions. In order to illustrate the stress level due to bending moment and shear force clearly and efficiently, the effective stress of thin plate bending is shown.  相似文献   
46.
47.
We study two-component ultracold fermions with repulsive interactions, which are loaded into a decorated square lattice. By combining the real-space dynamical mean-field theory with the numerical renormalization group method, we discuss magnetic properties in the system. It is clarified how the ferromagnetically ordered ground state, which is stabilized by a flat band mechanism, is adiabatically connected to the ferrimagnetically ordered state expected in the strong coupling limit.  相似文献   
48.
49.
In this study, the Green's function of a point dislocation for the mixed boundary value problem of a thin plate is derived and then employed to analyze the interaction problem between a partially bonded rigid inclusion and a line crack in an infinite plate under uniform bending moments at infinity. A rational mapping technique and the complex stress function approach are used in the derivation. Based on the method of analytical continuation, the problem of obtaining the stress functions is reduced to a Riemann-Hilbert problem. Without loss of generality, the numerical results are demonstrated for a square rigid inclusion with a debonding. The stress intensity factors of crack tips and the stress intensities of debonding tips are shown for various parameters.  相似文献   
50.
Removal of protein dissolved in water by batch foam separation was conducted with using ovalbumin (OA) as a model protein in the light of wastewater treatment reducing organic loading. The removal efficiency had a maximum value near the i.e.p. of OA (pH 4.6); thus, most experiments were conducted at pH 4.6. Typical experimental conditions; superficial gas velocity, U(g): 1.97 x 10(-2)-5.37 x 10(-2)cm/s; initial bulk concentration of OA, C(i): ca. 0.05-0.25 g/L; liquid volume, V: 600 cm(3). A model estimating bulk concentration profile was proposed by taking into account a mass balance of the present system. The model predicted that OA could be removed perfectly, however, was not all removed experimentally. The residual OA concentration of the bulk liquid within the column reached plateau value, which correspond to ca. 18% of the initial OA concentration. The plateau value of the bulk concentration was attained for ca. 100-500 min with U(g)=1.97 x 10(-2)-5.37 x 10(-2)cm/s. Foaming ability test revealed that the foaming limit concentration of OA at pH 4.6 was 9.72 x 10(-3)g/L. These results suggested that OA molecules could be damaged by interaction of bubble surface in the dispersed phase, since there were the residual OA concentrations over the limit concentration. To take account of this phenomena and correct the model, average surface density, X(d), which should convert protein molecule into the denatured protein molecule, was introduced. The corrected model could explain well the time profile of OA bulk concentration.  相似文献   
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