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151.
对于单调线互补问题提出了一种新的内点算法-高阶仿射尺度算法,算法的每一步近代,利用高原始-对偶内点算法的思想求解一个方程组得到迭代方向,再适当选取步长,使算法具有多项式复杂性。 相似文献
152.
以泛函分析的观点来考察连续小波变换及小波框架算子,得到了它们的一些性质,并给出了严格证明,弥补了有关献中的不足。 相似文献
153.
一类完备Riemann流形上的有界调和函数 总被引:2,自引:0,他引:2
本文我们将对一类完备Riemann流形上的有界调和函数所组成的线性空间的维数的上界进行估计,同时给出了一个关于测地球体积的Bishop-Gromov型体积比较定理。 相似文献
154.
Yaohui Lv Hong Liu Zhen wang Lujiang Hao Jing Liu Yangmin Wang Guojun Du Duo Liu Jie Zhan Jiyang Wang 《先进技术聚合物》2008,19(11):1455-1460
Silver nanoparticles were covalently coated on a glass surface by overnight exposure of the glass substrate to nanoparticle solutions, using 3‐aminopropyltriethoxysilane (APTES) as a coupling agent. Washing and air‐drying yield a uniformly coated glass substrate, which can be used as a material capable of killing harmful microorganisms in food industry. Nanoparticles are stable on the glass surface and are not washed away by water; they even remain on the glass surface under short‐term ultrasonic irradiation. The morphology of silver nanoparticles on the glass substrate was characterized by scanning electron microscope (SEM). The existence of Ag nanoparticles on the substrate was also confirmed by ultraviolet‐visible (UV–Vis) spectroscopy. Fourier transform infrared (FT‐IR) measurement shows that the connection is based on covalent bonds between silver nanoparticle surface/APTES molecules. Combining the effects of low cost and effectiveness in prohibiting the growth of Escherichia coli, such materials are expected to be used as antibacterial coatings, which may have large potential applications in food industry. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
155.
设Ω为R~π中的有界区域,其边界Ω充分光滑,M为乘积空间multiply from j=0 to m-1 (H~(m-j-(1/2))(Ω))的任一子空间,M~⊥≡{multiply from j=1 to m (V_j)∈multiply from j=2m-1 to m (H~(m-j-(1/2))(Ω))|multiply from j=1 to m ( 相似文献
156.
157.
Based on a one-dimensional magnetic photonic crystal made of magneto-optic material, a tunable double-channel filter is presented. The tunability of such a filter can be achieved by defect mode splitting in the presence of external magnetic fields. Using the 4×4 transfer matrix method, the influences of the structural and compositional parameters are also analyzed, such as the magneto-optical effect, number of layers and angle of incidence. 相似文献
158.
Junliang Li Shaorong wang Zhenrong Wang Jiqin Qian Renzhu Liu Tinglian Wen Zhaoyin Wen 《Journal of Solid State Electrochemistry》2010,14(4):579-583
The study elementarily investigated the effect of the cathode structure on the electrochemical performance of anode-supported
solid oxide fuel cells. Four single cells were fabricated with different cathode structures, and the total cathode thickness
was 15, 55, 85, and 85 μm for cell-A, cell-B, cell-C, and cell-D, respectively. The cell-A, cell-B, and cell-D included only
one cathode layer, which was fabricated by
( \textLa0.74 \textBi0.10 \textSr0.16 )\textMnO3 - d \left( {{\text{La}}_{0.74} {\text{Bi}}_{0.10} {\text{Sr}}_{0.16} } \right){\text{MnO}}_{{3 - \delta }} (LBSM) electrode material. The cathode of the cell-C was composed of a
( \textLa0.74 \textBi0.10 \textSr0.16 )\textMnO3 - d - ( \textBi0.7 \textEr0.3 \textO1.5 ) \left( {{\text{La}}_{0.74} {\text{Bi}}_{0.10} {\text{Sr}}_{0.16} } \right){\text{MnO}}_{{3 - \delta }} - \left( {{\text{Bi}}_{0.7} {\text{Er}}_{0.3} {\text{O}}_{1.5} } \right) (LBSM–ESB) cathode functional layer and a LBSM cathode layer. Different cathode structures leaded to dissimilar polarization
character for the four cells. At 750°C, the total polarization resistance (R
p) of the cell-A was 1.11, 0.41 and 0.53 Ω cm2 at the current of 0, 400, and 800 mA, respectively, and that of the cell-B was 1.10, 0.39, and 0.23 Ω cm2 at the current of 0, 400, and 800 mA, respectively. For cell-C and cell-D, their polarization character was similar to that
of the cell-B and R
p also decreased with the increase of the current. The maximum power density was 0.81, 1.01, 0.79, and 0.43 W cm−2 at 750°C for cell-D, cell-C, cell-B, and cell-A, respectively. The results demonstrated that cathode structures evidently
influenced the electrochemical performance of anode-supported solid oxide fuel cells. 相似文献
159.
Hui Liu Hongliang Li Zhaolong Ding Aiping Fu Hongyan wang Peizhi Guo Jianqiang Yu Cunguo Wang Xiu Song Zhao 《Journal of Cluster Science》2012,23(2):273-285
Using the surface charged and acid dissolvable melamine formaldehyde (MF) microspheres as sacrificial hard templates, silica coated MF core?Cshell composite microspheres, denoted as MF@SiO2, were synthesized via a surfactant-assisted sol?Cgel process by using tetraethyl orthosilicate (TEOS) as silica source. Hollow SiO2 spheres with mesoporous shells were then obtained after selective removal of the MF cores and the pore directing surfactant by hydrochloric acid etching or calcinations in air. Interesting shrinkage phenomena were observed in both the hollow products derived from hydrochloric acid etching and calcinations. The influence of the ratio of MF sphere to TEOS and the removal method of the MF core on the size of the hollow spheres, the shell thickness and the shell surface roughness have been studied. The composition, the thermal stability, the morphology, the surface area and pore size distribution, the wall thickness and adsorption properties of the hollow spheres derived from hydrochloric acid etching and calcinations were also investigated and compared based on the FTIR, SEM, TEM, TGA, Nitrogen adsorption?Cdesorption and spectrophotometer techniques or measurements. 相似文献
160.