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A new type of mesh generator is developed by using a self-organized pattern in a reaction–diffusion system. The system is the Gray–Scott model, which creates a spot pattern in a specific parameter region. The spots correspond to nodes of a mesh. The mesh generator has several advantages: the algorithm is simple and processes to improve the mesh, such as smoothing, (locally) addition, and removal of nodes, are automatically performed by the system.  相似文献   
2.
New semi‐rigid thermotropic liquid crystalline (LC) polyesters composed of a quaterphenyl analogue of 2,2′‐bis(1,3,4‐thiadiazole) were synthesized by high‐temperature solution polycondensation of a dioxydiundecanol derivative of 5,5′‐diphenyl‐2,2′‐bis(1,3,4‐thiadiazole) with four diacyl chlorides, whose structures were characterized by FT‐IR and 13C NMR spectroscopy, as well as elemental analysis. Differential scanning calorimetry (DSC) measurements and texture observations using polarizing microscopy displayed that all the polyesters form stable enantiotropic smectic and/or nematic LC phases. Solution and solid state absorption and fluorescence spectra indicated that the polyesters show absorption maxima arising from the 2,2′‐bis(1,3,4‐thiadiazole) moiety and emit bluish green light, the Stokes shifts being 129 nm in solution and 60–64 nm in the solid state. Band gap energies of the polyesters calculated from the solid state absorption spectra were 2.67–2.82 eV.  相似文献   
3.
Colloid and Polymer Science - The composition of vehicle on the reversible sol-gel transition temperature in a ternary system made up of methylcellulose (MC), polyethylene glycol (PEG), and citric...  相似文献   
4.
New semi-rigid homo- and copolyesters composed of the quaterphenyl analogue of 2,2'-bis(1,3,4-thiadiazole) (BTD), 5,5'-diphenyl-2,2'-bis(1,3,4-thiadiazole) (DBTD), were prepared by high temprature solution polycondensation of monomers, 3,3'- and 4,4'-dioxydiundecanol derivatives of DBTD with four dimethyl esters, and their liquid crystalline (LC) and optical properties were investigated. DSC measurements, texture observations using a polarizing microscope equipped with a hot stage, and powder X-ray diffraction showed that the homopolymers containing the 4,4'-DBTD unit form more stable LC phases than those having the 3,3'-DBTD unit. The 4,4'-DBTD-containing polymers and the 3,3'-DBTD unit-poor copolymers, except for the 3,3'-DBTD unit-rich copolymers and the 3,3'-DBTD-containing homopolymers (which formed highly ordered smectic or crystal mesophases), displayed a thermotropic LC smectic C phase. Solution and solid state UV-vis and photoluminescent (PL) spectra showed that the polyesters display miximum absorbances and bluish-green or blue emission based on the DBTD unit, where the Stokes shifts were observed. The peak positions in the UV-vis and the PL spectra of homopolymers composed of the 4,4'-DBTD unit were at higher wavelengths than those in the corresponding 3,3'-DBTD-containing homopolymers, due to its more conjugated structure. In the copolymers the peak maxima were shifted to shorter wavelengths with the increase of 3,3'-DBTD content.  相似文献   
5.
β-Substituted α-fluoro-α,β-unsaturated carboxylic acids have been successfully synthesized, usually in a (Z)-stereospecific manner by way of a stepwise or a one-pot three-step procedure starting from 2-chloro-1,1,1,2-tetrafluoroethane (HCFC-124), one of the major byproducts of the industrial process for tetrafluoroethene formation from chlorofluoromethane (HCFC-22).  相似文献   
6.
In this paper, we propose new energy dissipative characteristic numerical methods for the approximation of diffusive Oldroyd‐B equations that are based either on the finite element or finite difference discretization. We prove energy stability of both schemes and illustrate their behavior on a series of numerical experiments. Using both the diffusive model and the logarithmic transformation of the elastic stress, we are able to obtain methods that converge as mesh parameter is refined. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
7.
With reference to a multiobjective two-person nonzero-sum game, we define nondominated equilibrium solutions and provide a necessary and sufficient condition for a pair of mixed strategies to be a nondominated equilibrium solution. Using the necessary and sufficient condition, we formulate a mathematical programming problem yielding nondominated equilibrium solutions. We give a numerical example and demonstrate that nondominated equilibrium solutions can be obtained by solving the formulated mathematical programming problem.  相似文献   
8.
A prototype of a mammalian cell array chip was developed on a flat glass surface. A superhydrophilic (water contact angle = 5°)/highly hydrophobic (120°) pattern was prepared on a fluorinated polymer-coated glass surface by means of photocatalytic lithography, and A549 (a human alveolar epithelial cell line), Hep G2 (a human hepatoma cell line) and mouse fibroblast 3T3 cells were inoculated onto the superhydrophilic regions. The cell populations were confined in the superhydrophilic regions for at least 24 h and separated from each other for at least one week. Organ-specific toxicity of aflatoxin B1 and non-specific toxicity of adriamycin were successfully detected by using the cell array chip.  相似文献   
9.
In most of studies on multiobjective noncooperative games, games are represented in normal form and a solution concept of Pareto equilibrium solutions which is an extension of Nash equilibrium solutions has been focused on. However, for analyzing economic situations and modeling real world applications, we often see cases where the extensive form representation of games is more appropriate than the normal form representation. In this paper, in a multiobjective two-person nonzero-sum game in extensive form, we employ the sequence form of strategy representation to define a nondominated equilibrium solution which is an extension of a Pareto equilibrium solution, and provide a necessary and sufficient condition that a pair of realization plans, which are strategies of players in sequence form, is a nondominated equilibrium solution. Using the necessary and sufficient condition, we formulate a mathematical programming problem yielding nondominated equilibrium solutions. Finally, giving a numerical example, we demonstrate that nondominated equilibrium solutions can be obtained by solving the formulated mathematical programming problem.  相似文献   
10.
Although molecular bromine (Br2) is a useful brominating reagent, it is not easy to handle. Herein, we describe the preparation of a novel air-stable bromine complex prepared from 1,3-dimethyl-2-imidazolidinone (DMI) and Br2, which was identified to be (DMI)2HBr3 by spectral and X-ray techniques. This complex was then used to brominate olefins, carbonyl compounds, and aromatics, as well as in the Hofmann rearrangement. Yields of reaction products using this complex were almost the same or superior to those using other bromine alternatives.  相似文献   
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