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961.
In this paper, two time relaxation parameters are introduce to a thermal lattice BGK, model to make its Prandtl number controllable. The dependency of the Prandtl number on the two parameters is derived. Numerical measurement of the transport coefficients is used to demonstrate the validity of the method. Furthermore, two examples of convective heat transfer are calculated, with one to show the effectiveness, and the other to show the breakdown of the two-parameter formulation under different conditions. 相似文献
962.
针对电力设施遥感图像云层遮挡问题,提出了基于生成对抗网络(GAN) 的遥感图像去云算法。以条件生成对抗网络 (cGAN) 为主体结构,在编码器自适应填充卷积,设计了基于 Soft Attention的递归神经网络模块,通过对所有特征节点增加 全局依赖关系来解决网络局部最优问题,通过空间信息转换提取关键信息,提高去云与重建效果。实验结果表明,方法对遥 感图像中云层遮挡去除效果较好,重建图像的结构相似性(SSIM) 与峰值信噪比(PSNR) 分别达到0.983与32.899,分别提高 了23.93%与8.86%,均优于其他改进型GAN 网络。研究的方法不仅为基于遥感图像电力设施识别提供了基础,深度学习 遥感图像处理应用提供了参考。 相似文献
963.
The emulsion blend method, which is environmentally friendly and energy saving, was used to prepare a compositional gradient film of fluorinated/non-fluorinated polyacrylate in this paper. The size and glass-transition temperature (Tg) of the emulsion particles were designed to enhance the driving force of their selective congregation and promote the formation of gradient structure. The structures and surface properties of the obtained films were characterized. The results showed that when the fluorinated components have much smaller particle size and higher Tg than those of fluorine-free polyacrylate components, the gradient structures formed in the direction across the film thickness of the films. The concentration of the fluorinated component increased gradually from film-glass interface to film-air interface in the blend film, making the surface free energies of the two sides of the gradient film distinctively different. 相似文献
964.
965.
PbS nanowires with 30 nm and 60 nm diameter fabricated under the same condition of electrochemical deposition with sulfuric and oxalic anodic alumina membranes (AAM), respectively, have been successfully prepared in order to study their optical properties in relation to their size. Scanning electron microscopy indicates that the 60 nm PbS nanowire arrays have the same shape with the 30 nm. X-ray diffraction result shows that 60 nm PbS nanowires are crystalline and have a highly (200) preferential orientation like 30 nm ones. UV spectrum considers the nanowire size decrease as the absorption peak shifts to the blue. The quantum confinement effects compared between 30 nm and 60 nm PbS nanowire arrays were observed by the measurements of ultraviolet-visible absorption spectroscopy (UV-vis). 相似文献
966.
A novel biosensor based on a myoglobin/gold nanoparticles/carbon spheres (Mb-AuNPs-CNs) 3-D architecture bioconjunction has
been fabricated for the determination of hydrogen peroxide (H2O2). Cyclic voltammetry (CV), Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM) were used
to characterize the bioconjunction of the AuNPs-CNs with Mb. Experimental results demonstrate that the AuNPs-CNs hybrid material
is more effective in facilitating electron transfer of the immobilized enzyme than CNs alone, which can be attributed to the
unique nanostructure and larger surface area of the bioconjunction. The biosensor displayed good performance for the detection
of H2O2 with a wide linear range from 0.28 μmol/L to 116.5 μmol/L and a detection limit of 0.12 μmol/L. The Michaelis-Menten constant
K
Mapp value was estimated to be 0.3 mmol/L. The resulting biosensor exhibited fast amperometric response, and good stability, reproducibility,
and selectivity to H2O2.
This article is published with open access at Springerlink.com 相似文献
967.
Min-Hua Chen Tomohiko Yoshioka Toshiyuki Ikoma Nobutaka Hanagata 《Science and Technology of Advanced Materials》2014,15(5)
Theranostic nanoparticles currently have been regarded as an emerging concept of ‘personalized medicine’ with diagnostic and therapeutic dual-functions. Eu3+ doped hydroxyapatite (HAp) has been regarded as a promising fluorescent probe for in vivo imaging applications. Additionally, substitution of Ca2+ with Fe3+ in HAp crystal may endow the capability of producing heat upon exposure to a magnetic field. Here we report a preliminary study of doping mechanism and photoluminescence of Eu3+ and Fe3+ doped HAp nanoparticles (Eu/Fe:HAp). HAp with varied concentration of Eu3+ and Fe3+ doping are presented as Eu(10 mol%):HAp, Eu(7 mol%)-Fe(3 mol%):HAp, Eu(5 mol%)-Fe(5 mol%):HAp, Eu(3 mol%)-Fe(7 mol%):HAp, and Fe(10 mol%):HAp in the study. The results showed that the HAp particles, in nano-size with rod-like morphology, were successfully doped with Eu3+ and Fe3+, and the particles can be well suspended in cell culture medium. Photoluminescence analysis revealed that particles have prominent emissions at 536 nm, 590 nm, 615 nm, 650 nm and 695 nm upon excitation at a wavelength of 397 nm. Moreover, these Eu/Fe:HAp nanoparticles belonged to B-type carbonated HAp, which has been considered an effective biodegradable and biocompatible drug/gene carrier in biological applications. 相似文献
968.
采用适射电子显微镜对五种Fc—C—N合金的板条马氏体的束内和束界区进行详细的观察和分析。研究发现板条马氏体组织中存在填塞马氏体。板条马氏体组织是由一簇簇平行排列的大小板条,以及填充在马氏体板条间,束界和界隅内的不定外形的填塞马氏体和条间残余奥氏体薄膜或膜片所构成。 相似文献
969.
A novel torsion sensor is proposed, which is composed of one long period fibre grating and one asymmetrically corrugated long period fibre grating based on the high-frequency CO2 laser pulses technology and burning fibre coating and etching cladding technology, respectively. By combing the advantages of the two aforementioned elements, a sensitivity of 331.7 and 310.3 pm/(rad/m) towards clockwise and anticlockwise direction, respectively, is reached in the experiments. 相似文献
970.
近几年各个三坐标测量软件开发厂商相继在自己的软件中加入了CAD功能,且功能越来越强大。本文就CAD在三坐标测量软件中的使用和其功能作简要阐述。 相似文献