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The relationship between exposure to sexually objectifying music television, primetime television programs, fashion magazines, and social networking sites and the internalization of beauty ideals, self‐objectification, and body surveillance was examined among adolescent girls (N = 558). A structural equation model showed direct relationships between sexually objectifying media and the internalization of beauty ideals, and indirect relationships between sexually objectifying media and self‐objectification, and body surveillance through the internalization of beauty ideals. The direct relationships between sexually objectifying media and the internalization of beauty ideals, self‐objectification, and body surveillance differed across the types of sexually objectifying media. The discussion focuses on the implications of these findings to explain self‐objectification among girls. 相似文献
144.
T. Dumelow A. A. Hamilton T. J. Parker D. R. Tilley C. T. B. Foxon D. Hilton K. J. Moore 《Journal of Infrared, Millimeter and Terahertz Waves》1990,11(8):901-917
We have used far-infrared oblique-incidence reflection spectroscopy to study bulk phonon polaritons, and attenuated total reflection (ATR) spectroscopy to study surface phonon polaritons, in long-period GaAs/AlxGa1?xAs and short-period GaAs/AlAs superlattices. Results on the former are in good agreement with an effective-medium bulk-slab model of the dielectric tensor of the superlattice; results on the latter are analysed in terms of a model that contains dielectric-tensor contributions from the confined optic phonons. 相似文献
145.
David Parker 《今日电子》2005,(4):102
Cirrus Logic公司新近推出名为“音频系统处理器”的CS496xxx系列集成电路产品,该系列芯片进一步降低了系统成本,减小了占板尺寸并增强了音频功能。 相似文献
146.
Xiaoying Qi Can Xue Xiao Huang Yizhong Huang Xiaozhu Zhou Hai Li Daojun Liu Freddy Boey Qingyu Yan Wei Huang Steven De Feyter Klaus Müllen Hua Zhang 《Advanced functional materials》2010,20(1):43-49
A novel dendrimer‐templating method for the synthesis of CuO nanoparticles and the in situ construction of ordered inorganic–organic CuO–G2Td(COOH)16rice‐shaped architectures (RSAs) with analogous monocrystalline structures are reported. The primary CuO nanoparticles are linked by the G2Td(COOH)16 dendrimer. This method provides a way to preserve the original properties of primary CuO nanoparticles in the ordered hybrid nanomaterials by using the 3D rigid polyphenylene dendrimer (G2Td(COOH)16) as a space isolation. The primary CuO nanoparticles with diameter of (6.3 ± 0.4) nm are synthesized via four successive reaction steps starting from the rapid reduction of Cu(NO3)2 by using NaBH4 as reducer and G2Td(COOH)16 as surfactant. The obtained hybrid CuO–G2Td(COOH)16 RSA, formed in the last reaction step, possesses a crystal structure analogous to a monocrystal as observed by transmission electron microscopy(TEM). In particular, the formation process of the RSA is monitored by UV–vis, TEM, and X‐ray diffraction. Small angle X‐ray scattering and Fourier transform infrared spectroscopy are used to investigate the role of the dendrimer in the RSA formation process. The obtained results illuminate that Cu2+? COO? coordination bonds play an indispensable role in bridging and dispersing the primary CuO nanoparticles to induce and maintain the hybrid RSA. More importantly, the RSA is retained through the Cu2+? COO?coordination bonds even with HCl treatment, suggesting that the dendrimers and Cu2+ ions may form rice‐shaped polymeric complexes which could template the assembly of CuO nanoparticles towards RSAs. This study highlights the feasibility and flexibility of employing the peculiar dendrimers to in‐situ build up hybrid architectures which could further serve as templates, containers or nanoreactors for the synthesis of other nanomaterials. 相似文献
147.
Elisa García‐Tabars John A. Carlin Tyler J. Grassman Diego Martín Ignacio Rey‐Stolle Steven A. Ringel 《Progress in Photovoltaics: Research and Applications》2016,24(5):634-644
The evolution of Si bulk minority carrier lifetime during the heteroepitaxial growth of III–V on Si multijunction solar cell structures via metal‐organic chemical vapor deposition (MOCVD) has been analyzed. In particular, the impact on Si lifetime resulting from the four distinct phases within the overall MOCVD‐based III–V/Si growth process were studied: (1) the Si homoepitaxial emitter/cap layer; (2) GaP heteroepitaxial nucleation; (3) bulk GaP film growth; and (4) thick GaAsyP1‐y compositionally graded metamorphic buffer growth. During Phase 1 (Si homoepitaxy), an approximately two order of magnitude reduction in the Si minority carrier lifetime was observed, from about 450 to ≤1 µs. However, following the GaP nucleation (Phase 2) and thicker film (Phase 3) growths, the lifetime was found to increase by about an order of magnitude. The thick GaAsyP1‐y graded buffer was then found to provide further recovery back to around the initial starting value. The most likely general mechanism behind the observed lifetime evolution is as follows: lifetime degradation during Si homoepitaxy because of the formation of thermally induced defects within the Si bulk, with subsequent lifetime recovery due to passivation by fast‐diffusing atomic hydrogen coming from precursor pyrolysis, especially the group‐V hydrides (PH3, AsH3), during the III–V growth. These results indicate that the MOCVD growth methodology used to create these target III–V/Si solar cell structures has a substantial and dynamic impact on the minority carrier lifetime within the Si substrate. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
148.
R.J. Kaplar D. Kwon S.A. Ringel A.A. Allerman Steven R. Kurtz E.D. Jones R.M. Sieg 《Solar Energy Materials & Solar Cells》2001,69(1)
DLTS measurements have been performed on InGaAsN. Four hole traps have been identified in 1.05 eV, p-type InGaAsN and the removal of a midgap trap (0.5 eV) during annealing has been correlated with improved bulk material properties. Improvements in MOCVD growth conditions resulted in a reduction of trap density in 1.05 eV, p-type InGaAsN. Increased indium and nitrogen composition has been correlated with higher defect concentrations in p-type InGaAsN. Two electron traps have been identified in 1.15 eV, n-type InGaAsN and annealing was found to reduce the density of the shallow electron trap. 相似文献
149.
Parker J. Anthony Kenyon Robert V. Young Lwarence R. 《IEEE transactions on bio-medical engineering》1985,(1):28-36
Two methods of measuring ocular torsion from digital images of the eyes were developed and tested. One method measures torsion from the translation of two landmarks using a rectilinear coordinate system. The second method measures torsion from the translation of two landmarks using a polar coordinate system. The center for the polar sampling is the center of the pupil. After thresholding and filtering the images, landmark translation is measured from the interpolated peak in the normalized cross correlation of the reference landmark with the image. 相似文献
150.
Levy Bruce P. Campbell Steven L. Rose Timothy L. 《IEEE transactions on bio-medical engineering》1986,(11):1046-1049
The geometric area of the tip of an intracortical stimulation electrode can be defined by combining photoresist masking with oxygen plasma etching of Parylene.1 The method was tested with both capacitor and iridium oxide electrodes and caused no significant degradation of the electrical properties of the electrode. 相似文献