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71.
J. Hu Y. Bando J. Zhan X. Yuan T. Sekiguchi D. Golberg 《Advanced materials (Deerfield Beach, Fla.)》2005,17(8)
The inside cover shows a scanning electron micrograph of a novel hierarchical heterostructures, as reported by Hu and co‐workers on p. 971. The heterostructures are formed from Si core microwires covered by dense, aligned SiO2 nanowires, thus forming multiple junctions to the cores. The inset shows a schematic of the Sn‐catalyzed vapor–liquid–solid growth mechanism. These materials are envisaged to become important for optical fibers, low‐dimensional waveguides, scanning near‐field optical microscopes and high‐bandwidth optical signal processing devices. 相似文献
72.
D. Kisailus M. Najarian J.C. Weaver D.E. Morse 《Advanced materials (Deerfield Beach, Fla.)》2005,17(10)
A system that acts as a biomimetic of the silica‐synthesizing enzyme found in a marine sponge is reported by Morse and co‐workers on p. 1234. Gold nanoparticles (GNPs) are functionalized with the same organic moieties that are found in the enzyme's catalytic site. Interaction between the nucleophilic (OH‐terminated) and hydrogen‐bonding (imidazole‐terminated) GNPs, as shown on the cover, is required for the hydrolysis of a silicon alkoxide precursor and subsequent polycondensation to form silica at a low temperature and near‐neutral pH. Replacement of either of the required functional groups by a non‐reactive methyl group abolishes catalysis in this synthetic system, as it does in the biological enzyme. Cover art provided by Peter Allen. 相似文献
73.
L.‐W. Yin Y. Bando J.‐H. Zhan M.‐S. Li D. Golberg 《Advanced materials (Deerfield Beach, Fla.)》2005,17(16)
Highly faceted wurtzite‐type ZnS nanotubes with hexagonal cross‐section morphologies have been self‐assembled via a controllable high‐temperature thermal‐chemical reaction route in work reported by Yin and co‐workers on p. 1972. The self‐assembly growth along c‐axis to highly hexagonal‐faceted ZnS single‐crystalline nanotubes is associated with the crystallographic characteristics, such as the non‐central and polar surfaces of the wurtzite‐type ZnS structure. The faceted ZnS nanotubes grow along the <0001> direction, and are closed by low‐index faces of non‐polar {1000} faces. The inside cover and insets show electron microscopy and scanning electron microscopy images of the faceted ZnS nanotubes. 相似文献
74.
T. Kraus L. Malaquin E. Delamarche H. Schmid N.D. Spencer H. Wolf 《Advanced materials (Deerfield Beach, Fla.)》2005,17(20)
The cover shows 100 μm diameter glass spheres covered by a grid of hexagonally packed polystyrene beads. Wolf and co‐workers placed the 500 nm diameter polystyrene beads onto the larger spheres using the self‐assembly, transfer, and integration (SATI) process that they report on p. 2438. The cover illustrates the capability of SATI to process uneven surfaces in addition to the planar substrates discussed in the article. The carrier that holds the smaller beads deforms during their transfer onto the larger spheres, so that on the larger spheres patterned “caps” are formed. Using this process, which is compatible with standard microfabrication techniques, a variety of particle assemblies can be achieved. 相似文献
75.
The aim of this work is to investigate the possibility of using electrostatic forces to actuate the membrane of a pressure sensor in order to create self-testing features in the system. It is shown that the electrostatic pressure is small compared with the external pressure, unless large voltages or electrical charges are used. The interrelation between electrostatic forces and externally applied pressure is calculated for different electrical drive modes of the capacitor, in the case of a uniform membrane and for a MESA-type membrane. 相似文献
76.
本文介绍了基於系统集的通用智能控制器的设计思想。作为示例,我们对一类具有相同特征与约束的系统集给出了基於稳态映照记忆模型的自学习算法,证明了它的可学习性与收敛性,在不同的对象上验证了它的通用性。 相似文献
77.
基于Kohonen自组织特征映射神经元网络图像分割方法的研究 总被引:5,自引:0,他引:5
传统图像分割技术对森林火灾图像分割效果不太理想,无法模仿人对颜色的主观判断,因此很难提取森林火灾图像的火焰区域,而K0llonen自组织特征映射神经元网络在这一方面表现出极大的灵活性和自适应性,能够模拟人的思维活动。本文利用Kohonen神经元网络自动对森林火灾图像分割和分类,获得卓有成效的效果,为森林火灾图像的自动识别奠定基础。 相似文献
78.
This review discusses recent developments in the areas of fabrication, certain types of optical characterization, and applications of a selected class of chemically assembled nanomaterials, namely i) gold and silver nanoparticles deposited onto optically transparent glass substrates; ii) thiol‐functionalized self‐assembled monolayers (SAMs); iii) chemically stabilized gold and silver nanoparticles (monolayer protected clusters, MPCs); and iv) MPCs linked to metallic substrates and adsorbates. Six linear optical techniques for the characterization of these materials are discussed: transmission localized surface plasmon resonance spectroscopy, T‐LSPR; propagating surface plasmon resonance spectroscopy, P‐SPR; polarization‐selective Fourier transform infrared reflection absorption spectroscopy, PS‐FTIRRAS; polarization‐modulation Fourier transform infrared reflection absorption spectroscopy, PM‐FTIRRAS; surface‐enhanced infrared reflection absorption spectroscopy, SEIRRAS; and infrared ellipsometry. The review focuses particularly on providing a unified treatment of these six optical techniques by using a relatively simple stratified multilayer model. 相似文献
79.
针对略阳电厂目前使用的母联电流相位比较式母差保护在现场运用中存在的问题,进行了深入的研究和探讨提出保护换型的必要性,及对微机母线保护的优点及动作情况进行简要分析。 相似文献
80.
Reports an error in 'It's the End of the World as We Know It': Threat and the Spatial-Symbolic Self" by Christopher T. Burris and John K. Rempel (Journal of Personality and Social Psychology, 2004[Jan], Vol 86[1], 19-42). The article contained two errors. On page 35, second column, line 14, two of the word fragments are notated incorrectly. The word shown as s[k]ull should be sk[u]ll, and the word shown as as[h]es should be as[h]e[s]. (The following abstract of the original article appeared in record 2003-11198-002.) According to amoebic self theory, the boundary defining the self encompasses 3 levels of self-representation--bodily, social, and spatial-symbolic. Study 1 related a newly developed measure of individual differences in sensitivity to boundary threat across these 3 domains to values and disgust sensitivity. Four subsequent studies focused on spatial-symbolic threat sensitivity and related it to right-wing authoritarianism, aversive reactions to unfamiliar out-groups, and revulsion to vermin. A final experiment illustrates how a salient spatial-symbolic threat (dust mites) can elicit reactions toward out-groups that closely parallel mortality salience effects observed in research inspired by terror management theory, even though dust mites do not elicit mortality concerns. The importance of preserving the familiar in order to preserve the self is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献