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81.
82.
Gregory S. Ho Chen Huang Emily A. Carter 《Current Opinion in Solid State & Materials Science》2007,11(5-6):57-61
Orbital-free density functional theory (OF-DFT) can be made to scale linearly with sample size, allowing thousands of atoms to be treated explicitly with quantum mechanics. State-of-the-art kinetic energy density functionals and ion–electron pseudopotentials are used to obtain accurate structural property predictions for nanoparticles, nanowires, extended surfaces, and nanoindentation of simple metals. 相似文献
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Several studies have suggested that primates react differently to spatial reduction. In this article, the authors tested some general hypotheses on primate response to spatial reduction by studying the Apenheul lowland gorillas (Gorilla gorilla gorilla; Apeldoorn, the Netherlands). The frequency of conflicts did not greatly change between the 2 housing settings, thus not supporting the density- aggression model. Indoor, gorillas performed touching behavior more often and increased their level of reconciliation. These findings support the coping model. Indoor, the gorillas also maintained broader interindividual distances by increasing the levels of sitting alone, avoidance, and dismissing behaviors. In conclusion, the Apenheul gorillas modified selectively the distribution of some patterns typical of their behavioral repertoire in response to a high-density condition. Both avoidance and coping tactics were used, thus revealing high levels of behavioral flexibility in this species. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
András Ványolos Balázs Dóra Attila Virosztek 《Journal of Superconductivity and Novel Magnetism》2007,20(7-8):643-645
We report of a theoretical study on quasi-one dimensional unconventional charge density wave (UCDW) driven by electron–phonon
interaction. Within mean field theory, we find that the wavevector dependence of the coupling leads to a momentum dependent
single particle gap on the Fermi surface. The presence of small energy single particle excitations around the gap nodes significantly
changes the optical conductivity compared to the conventional CDW result. In addition to that, the collective phase excitation
arising from fluctuation of the order parameter leads to further qualitative changes of the conductivity and results in an
effective mass that is nonmonotonic in temperature.
相似文献
86.
The fabrication and characterization of two‐photon polymerized features written within and outside of colloidal crystals is presented. Two‐photon polymerization (TPP) response diagrams are introduced and developed to map the polymerization and damage thresholds for features written via modulated beam rastering. The use of tris[4‐(7‐benzothiazol‐2‐yl‐9,9‐diethylfluoren‐2‐yl)phenyl]amine (AF‐350) as an initiator for TPP is demonstrated for the first time and TPP response diagrams illustrate the polymerization window. These diagrams also demonstrate that the polymerization behavior within and outside of colloidal crystals is similar and electron microscopy reveals nearly identical resolution. Fluorescence confocal microscopy further enables visualization of non‐self‐supporting, three‐dimensional TPP features within self‐assembled photonic crystals. Finally, microspot spectroscopy is collected from a two‐photon feature written within a colloidal crystal and this is compared with simulation. 相似文献
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山西省横泉水库在原有遗留工程基础上进行重新建设,以往的4次施工,填兢了长400m、高17m左右的左岸坝体,填土约120万m^3,但坝体填筑质量极差,干客重和渗透系数根本无法满足设计要求。此次重新建设,决定对这部分干客重不迭设计要求且具有湿陷性的左岸旧坝体以及左岸黄土台地进行强夯处理,对坝体进行强夯处理在省内还是首次进行,在国内也比较少见,通过处理,坝体质量达到了设计要求,并且节约了投资,效果明显。 相似文献
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