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81.
《Optimization》2012,61(12):2091-2116
ABSTRACTThe aim of this paper is, in the setting of normed spaces with a cone K non necessarily solid, to study new relations among set scalarization functions that are extensions of the oriented distance of Hiriart-Urruty. Moreover, we deal with a set scalarization function of sup-inf type, we investigate its relation to the cone-properness and cone-boundedness and it is related to other set scalarizations existing in the literature. In particular, with the norm induced by the Minkowski's functional, we obtain relations with a set scalarization which is an extension of the so called Gerstewitz's scalarization function. 相似文献
82.
A facile approach to construct ferroferric oxide/chitosan composite scaffolds with three-dimensional oriented structure has been explored in this research.Chitosan and ferroferric oxide are co-precipitated by using an in situ precipitation method,and then lyophilized to get the composite scaffolds.XRD indicated that Fe3O4 was generated during the gel formation process,and increasing the content of magnetic particles could destruct the crystal structure of chitosan. When the content of magnetic particles is lower than 10%,the layer-by-layer structure and wheel spoke structure arc coexisting in the scaffolds.Increasing the content of magnetic particles,just layer-by-layer structure could be observed in the scaffolds.Ferroferric oxide particles were uniformly distributed in the matrix,the size of which was about 0.48μm in diameter,2μm in length.Porosity of magnetic chitosan composite scaffolds is about 90%.When the ratio of ferroferric oxide to chitosan is 5/100,the compressive strength of the material is 0.4367 MPa,which is much higher than that of pure chitosan scaffolds,indicating that the layer-by-layer and wheel spokes complex structure is beneficial for the improvement of the mechanical properties of chitosan scaffolds.However,increasing the content of ferroferric oxide,the compressive strength of scaffolds decreased,because of the decreasing of chitosan crystallization and aggregation of magnetic particles as stress centralized body.Another reason is that the layer-by-layer and wheel spokes complex structure makes bigger contributions for the compressive strength than the layer-by-layer structure does.Three-dimensional ferroferric oxide/chitosan scaffolds could be used as hyperthermia generator system,improving the local circulation of blood, promoting the aggradation of calcium salt and stimulating bone tissue regeneration. 相似文献
83.
植物叶片的脉络与形态是研究植物特征的重要出发点,其包含了植物的内在属性及重要遗传信息,对植物种类的识别起着关键作用.由于植物叶片边缘及叶脉的复杂多变性,已有的叶脉提取方法难以有效地提取叶脉细节.针对以往方法的不足,利用图像方向能量方法进行植物叶脉提取,实验结果表明该方法能够提出较丰富的叶脉细节和边缘信息,提高了提取的精确性. 相似文献
84.
High temperature thermoelectric properties of highly c-axis oriented Bi2Sr2Co2Oy thin films fabricated by pulsed laser deposition
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High-temperature thermoelectric transport property measurements have been performed on the highly c-axis oriented Bi2Sr2Co20v thin films prepared by pulsed laser deposition on LaA1Oa (001). Both the electric resistivity p and the seebeck coefficient S of the film exhibit an increasing trend with the temperature from 300 K-1000 K and reach up to 4.8 m. cm and 202 V/K at 980 K, resulting in a power factor of 0.85 mW/mK which are comparable to those of the single crystalline samples. A small polaron hopping conduction can be responsible for the conduction mechanism of the film at high temperature. The results demonstrate that the Bi2Sr2Co2Oy thin film has potential application has high temperature thin film thermoelectric devices, 相似文献
85.
High temperature thermoelectric properties of highly c-axis oriented Bi<sub>2</sub>Sr<sub>2</sub>Co<sub>2</sub>O<sub>y</sub> thin films fabricated by pulsed laser deposition
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High-temperature thermoelectric transport property measurements have been performed on the highly c-axis oriented Bi2Sr2Co2Oy thin films prepared by pulsed laser deposition on LaAlO3(001).Both the electric resistivity ρ and the seebeck coefficient S of the film exhibit an increasing trend with the temperature from 300 K-1000 K and reach up to 4.8 m·Ω· cm and 202 μV/K at 980 K,resulting in a power factor of 0.85 mW/mK which are comparable to those of the single crystalline samples.A small polaron hopping conduction can be responsible for the conduction mechanism of the film at high temperature.The results demonstrate that the Bi2Sr2Co2Oy thin film has potential application in high temperature thin film thermoelectric devices. 相似文献
86.
Yang Liu Doctor 《应用数学和力学(英文版)》2000,21(11):1320-1330
The problem of controllability of nonlinear control system is a significant field which has an extensive prospect of application. A.M.Kovalev of Ukraine Academy of Science applied the oriented manifold method developed in dynamics of rigid body to nonlinear control system for the first time and obtained a series of efficient results. Based on Kovalev’s oriented manifold method, firstly, by invariant manifold method the problem of controllability of nonlinear control system was studied and the necessary condition of the controllability of a kind of affine nonlinear system was given out. Then the realization of the necessary condition was discussed. At last, the motion of a rigid body with two rotors was investigated and the necessary condition which is satisfied by this system was proved. 相似文献
87.
运用图论方法和极大代数方法,研究了非强连通图中的强连通分支的最大圈长平均值与该图的赋权邻接矩阵的特征值之间的关系,并进一步证明了其等价性. 相似文献
88.
R. Ezhil Vizhi S. Kalainathan G. Baghavan Narayana 《Crystal Research and Technology》2007,42(11):1104-1109
Glycine phosphite [NH3CH2COOH3PO3], abbreviated as GPI is the second hydrogen bonded ferroelectric crystal combination of phosphorous acid and amino acid following βnine phosphite crystals abbreviated as BPI. Sankaranarayanan and Ramasamy‐Technique was adopted to prepare the ferroelectric glycine phosphite unidirectional single crystal. The growth orientation was imposed by the pre‐grown 〈010〉 seed. As water was the solvent, transparent, colourless crystal with cylindrical shaped ingot of sized 20mm‐diameter was grown. Powder X‐ray diffraction, HRXRD, FTIR, dielectric and mechanical studies were carried out. The results are discussed in detail. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
89.
Dr. Carles Acosta-Silva Prof. Joan Bertran Prof. Vicenç Branchadell Prof. Antoni Oliva 《Chemphyschem》2020,21(4):295-306
The Kemp elimination reaction is the most widely used in the de novo design of new enzymes. The effect of two different kinds of electric fields in the reactions of acetate as a base with benzisoxazole and 5-nitrobenzisoxazole as substrates have been theoretically studied. The effect of the solvent reaction field has been calculated using the SMD continuum model for several solvents; we have shown that solvents inhibit both reactions, the decrease of the reaction rate being larger as far as the dielectric constant is increased. The diminution of the reaction rate is especially remarkable between aprotic organic solvents and protic solvents as water, the electrostatic term of the hydrogen bonds being the main factor for the large inhibitory effect of water. The presence of an external electric field oriented in the direction of the charge transfer (z axis) increases it and, so, the reaction rate. In the reaction of the nitro compound, if the electric field is oriented in an orthogonal direction (x axis) the charge transfer to the NO2 group is favored and there is a subsequent increase of the reaction rate. However, this increase is smaller than the one produced by the field in the z axis. It is worthwhile mentioning that one of the main effects of external electric fields of intermediate intensity is the reorientation of the reactants. Finally, the implications of our results in the de novo design of enzymes are discussed. 相似文献
90.
H. Krbecek J. K. Krüger M. Pietralla 《Journal of Polymer Science.Polymer Physics》1993,31(11):1477-1485
To overcome the difficulties in measuring high-frequency shear constants of polymeric materials by ultrasonic or Brillouin scattering technques, we extrapolate results from oriented materials to zero birefringence. Shear constants C44 in the high-frequency limit (GHz) are determined for polyethylene, poly(ethylene terephthalate), poly(vinyl chloride), poly(methyl methacrylate), and polycarbonate using Brillouin scattering. Accurate values of Poisson's ratio are derived. The extrapolation to full orientation using an amended Moseley relation gives upper bounds for the “intrinsic birefringence.” Changes in the character of the orientation process are easily detected by monitoring the mode numbers, which are defined by analogy to Poisson's ratio. Extrapolation of these ratios to their upper bound 0.5 gives an independent check of the maximum intrinsic birefringence. © 1993 John Wiley & Sons, Inc. 相似文献