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101.
102.
Mizokami Y Kamesaki C Ito N Sakaibara S Yaguchi H 《Journal of the Optical Society of America. A, Optics, image science, and vision》2012,29(2):A118-A127
We examined whether the perception of the colorfulness of an image is influenced by the adaptation of the visual system to natural and shuffled images with different degrees of saturation. In the experiment, observers first became adapted to several images with different levels of saturation and then their colorfulness perception of a test image was measured. The results show that their perception of colorfulness was influenced by their adaptation to the saturation of images. The effect was stronger following adaptation to natural images than to images consisting of a shuffled collage of randomized color blocks, which suggests that the naturalness of the spatial structure of an image affects the strength of the effect. 相似文献
103.
J. L. Her K. Suga K. Kindo S. Takeyama H. Berger H. D. Yang Y. H. Matsuda 《Journal of Low Temperature Physics》2010,159(1-2):101-104
We performed high-field magnetization measurements, M(H), on the Ni5(TeO3)4Br2 by using a pulse magnet. The Ni2+ ions (S = 1) of this compound form a two dimensional distorted spin frustrated system (distorted kagome lattice), and undergo a Neel transition at T N ~29 K, due to the anisotropy. Below T N , a complex spin arrangement which contains ten spin sub-lattices was suggested by neutron scattering and electron spin resonance studies. We observed a step-like transition at H c ~11 T when T<T N . By contrast, at T>T N , the field-dependent magnetization curves behaved like a straight line. The H c is close to those obtained by previous spin resonance studies of Ni5(TeO3)4Br2 and Ni5(TeO3)4Cl2 in which a spin-flop-like transition was proposed to explain the field-dependent resonance spectra. Interestingly, the observed change in magnetization (ΔM) at H c corresponds to nearly one-half of the magnetic moment of Ni2+ ion, suggesting that the observed step-like behavior possibly corresponds to a spin-flip-like transition (i.e. from antiferromagnetic state to ferrimagnetic state). In addition, in the high-field region (H>H c ), the M(H) curves did not show plateau behavior, but exhibited the straight lines having finite slopes without any sign of saturation up to 55 T. 相似文献
104.
Mitsuharu Tabuchi Yoko Nabeshima Kuniaki Tatsumi Yoshiaki Nitta 《Journal of power sources》2010,195(3):834-844
Fe-substituted Li2MnO3 including a monoclinic layered rock-salt structure (C2/m), (Li1+x(FeyMn1−y)1−xO2, 0 < x < 1/3, 0.1 ≤ y ≤ 0.5) was prepared by coprecipitation-hydrothermal-calcination method. The sample was assigned as two-phase composite structure consisting of the cubic rock-salt () and monoclinic ones at high Fe content above 30% (y ≥ 0.3), while the sample was assigned as a monoclinic phase (C2/m) at low Fe content less than 20%. In the monoclinic Li2MnO3-type structure, the Fe ion tends to substitute a Li (2b) site, which corresponds to a center position of Mn4+ hexagonal network in Mn-Li layer. The electrochemical properties including discharge characteristics under high current density (<3600 mA g−1 at 30 °C) and low temperature (<−20 °C at 40 mA g−1) were severely affected by chemical composition (Fe content and Li/(Fe + Mn) ratio), crystal structure (monoclinic phase content) and powder property (specific surface area). Under the optimized Fe content (0.2 < y < 0.4), the Li/sample cells showed high initial discharge capacity (240-300 mAh g−1) and energy density (700-950 mWh g−1) between 1.5 and 4.8 V under moderate current density, 40 mA g−1 at 30 °C. Results suggest that Fe-substituted Li2MnO3 would be a non-excludable 3 V positive electrode material. 相似文献
105.
Li Jin; Yamamoto Yoko; Luo Lily; Batchelor Andrea K.; Bresnahan Richard M. 《Canadian Metallurgical Quarterly》2010,46(6):1637
The developing views of the purposes of school learning (PSLs) and related achievement among immigrant Chinese preschoolers and their European American (EA) age-mates were examined. Both culture and socioeconomic status (SES) were considered simultaneously, an often neglected research approach to studying Asian children. One hundred and fifty 4-year-olds—50 each of middle-class Chinese (CHM), low-income Chinese (CHL), and EA children—completed 2 story beginnings about school and were also tested for their language and math achievement. Results showed that 4-year-olds held sophisticated PSLs, ranging from intellectual to social and affect benefits. Large cultural and SES differences also emerged. CHM children mentioned more adult expectation and seriousness of learning than EA children who expressed more positive affect for self and compliance with adults. CHL children mentioned fewest PSLs. Achievement scores for oral expression of both immigrant groups were significantly lower than those of EA children despite similar reading and math achievement. Controlling for culture and SES, the authors found that children's articulated intellectual, but not other purposes, uniquely predicted their achievement in all tested domains. Cultural and SES influences on immigrant children are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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107.
Silica (SiO2)‐crosslinked polystyrene (PS) particles possessing photofunctional N,N‐diethyldithiocarbamate (DC) groups on their surface were prepared by the free‐radical emulsion copolymerization of a mixture of SiO2 (diameter = 20 nm), styrene, divinyl benzene, 4‐vinylbenzyl N,N‐diethyldithiocarbamate (VBDC), and 2‐hydroxyethyl methacrylate with a radical initiator under UV irradiation. In this copolymerization, the inimer VBDC had the formation of a hyperbranched structure by a living radical mechanism. The particle sizes of such core–shell structures [number‐average particle diameter (Dn) = 35–40 nm] were controlled by the variation of the feed amounts of the monomers and surfactant, or emulsion system. The size distributions were relatively narrow (weight‐average particle diameter/Dn ≈ 1.05). These particles had DC groups on their surface. Subsequently, poly(methyl methacrylate) brush encapsulated SiO2 particles were synthesized by the grafting from a photoinduced atom transfer radical polymerization approach of methyl methacrylate initiated by SiO2‐crosslinked PS particles as a macroinitiator. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
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Milk‐derived peptide Val‐Pro‐Pro (VPP) inhibits obesity‐induced adipose inflammation via an angiotensin‐converting enzyme (ACE) dependent cascade
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