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1.
Shmuel Borenstain Gil Bar-Haim Keren Goldshtein Gili Cohen-Taguri 《Color research and application》2020,45(6):1153-1169
Investigation of ink formulation options with the purpose to obtain color-gamut-optimal set of Cyan Magenta and Yellow CMY inks is reported. Implementation of the thickness dependent Kubelka-Munk model on multiple ink layers having different and well-defined thicknesses, provides characteristic absorption and scattering (K, S ) spectra of the ink ingredients. These data enable accurate computation of the reflectance spectrum and thus the L*a*b* color coordinates for any given ink thickness or substrate. Pigment materials investigated are quinacridone as magenta, copper-phthalocyanine as cyan, and arylide yellow. Scaling the peak of the absorption band to the number of molecules per unit area for the specific pigments studied in this article provides the molar extinction coefficients, 1.21 × 104 , 4.7 × 104 , and 3.3 × 104 cm2/millimole respectively, regardless of the different ink formulations used, in accord with Avogadro's principle. Having a set of three pairs of K, S spectra is used to compute the color gamut of any CMY color combination in the L*a*b* space as a function of ink layer thickness and formulation. Using an iterative algorithm, a color-gamut-optimal set of CMY inks is obtained. 相似文献
2.
Rats received a single pairing of an auditory conditioned stimulus (CS) with a footshock unconditioned stimulus (US). The fear (freezing) that had accrued to the CS was then extinguished. Injection of naloxone prior to this extinction significantly impaired the development of extinction. This impairment was mediated by opioid receptors in the brain and was not observed when naloxone was injected after extinction training. Finally, an injection of naloxone on test failed to reinstate extinguished responding that had already accrued to the CS. These experiments show that opioid receptors regulate the development, but not the expression, of fear extinction and are discussed with reference to the roles of opioid receptors in US processing, memory, and appetitive motivation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
Drew Michael R.; Yang Cynthia; Ohyama Tatsuya; Balsam Peter D. 《Canadian Metallurgical Quarterly》2004,30(3):163
Three experiments investigated the effects of varying the conditioned stimulus (CS) duration between training and extinction. Ring doves (Streptopelia risoria) were autoshaped on a fixed CS-unconditioned stimulus (US) interval and extinguished with CS presentations that were longer, shorter, or the same as the training duration. During a subsequent test session, the training CS duration was reintroduced. Results suggest that the cessation of responding during an extinction session is controlled by generalization of excitation between the training and extinction CSs and by the number of nonreinforced CS presentations. Transfer of extinction to the training CS is controlled by the similarity between the extinction and training CSs. Extinction learning is temporally specific. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
Almond preferences were produced by giving rats a mixture of almond and sucrose (Experiments 1-4) or saccharin (Experiment 4). A subsequent extinction procedure consisted of either repeated 2-bottle almond versus water tests (Experiment 1) or repeated exposure to almond alone (Experiments 2-4). The main independent variable was whether access to food following a session was given immediately, 30 min later, or 120 min later. No effect of extinction was found in any experiment. An important finding was that varying the delay until food access had no detectable effect. It was concluded that inadvertent flavor-food associations do not maintain preference for the flavor under extinction conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
Thermal Radiative Properties of Xonotlite Insulation Material 总被引:1,自引:0,他引:1
X inxin ZHANG Gaosheng WEI Fan YU Department of Thermal Engineering University of Science & Technology Beijing Beijing China Professor 《热科学学报(英文版)》2005,14(3):281-283,253
Introduction Xonotlite-type calcium silicate (6CaO?6SiO2?H2O) is synthesized porous insulation material by hydrothermal processing with quartz powder and limestone as the raw material (with CaO/ SiO2≈1:1). Compared with fire- retardant fibre, xonotlite has more excellent insulating performance, such as low thermal conductivity, environment friendly, high intension, and wide applying temperature range, which has been emphasized in recent years by many scholars and widely used in many indu… 相似文献
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采用高TiO2 含量聚酯切片 ,选择合适的熔融纺丝和加弹工艺路线 ,可以生产具有柔和光泽和一定抗紫外效果的亚光DTY长丝 相似文献
8.
论述一种用透射谱包络线法计算非晶薄膜的折射率、消光系数和光学带隙的方法。通过正交实验确定除压强之外的工艺参数,研究压强的改变对薄膜主要光学常数的影响,运用最小二乘法、内插值法在matlab编程基础上,拟合出光学常数曲线,借由观察曲线的特点,分析在低工作气压下,气压的改变对光学常数的影响。 相似文献
9.
Tiesong Xu Minghui Zhong Xiaolin Liang Jia Liu Bin Yan Jing Xiao Kai Jiao Xiange Wang Nian Si Zhongda Pan Zheming Zhao Xunsi Wang Peiqing Zhang Qiuhua Nie Shengchuang Bai Rongping Wang Junjie Zhang 《Journal of the American Ceramic Society》2021,104(11):5671-5678
Extinction ratio (ER) is one of the important parameters to characterize the polarization-maintaining (PM) performance of the fiber. In this paper, we report the preparation and properties of a novel chalcogenide microstructure fiber with a high ER. We fabricate a preform using a peeled-off extrusion method. The core and cladding material of the fiber are Ge9As23Se68 and Ge10As22Se68. The preform was drawn into a fiber with an average ER of −17.08 dB. The loss of the fiber is less than 2 dB over 5.20–8.55 μm, and the minimum loss of the fiber is 0.57 dB/m at 6.2 μm. Moreover, a flat mid-infrared supercontinuum spectrum spanning from 1.53 to 12.50 μm is generated by pumping an 18-cm-long PM fiber for the first time. 相似文献
10.
针对现有换相失败分析方法未考虑交流系统故障后直流电流动态上升对关断角影响的问题,在分析直流电流变化对关断角影响的基础上,首先推导了对称故障下未考虑直流电流变化以及考虑直流电流瞬时变化的换相失败分析方法。分析结果表明,当逆变侧换流母线电压跌落在一定区间内,以上2种方法会导致换相失败判别结果不准确。为此考虑交流系统故障后直流线路和直流控制的动态过程,推导了直流电流的时域表达式,通过求解直流电流最大值,提出了一种考虑直流电流动态上升的换相失败分析方法。最后基于PSCAD/EMTDC仿真平台验证了所提方法的有效性以及对高压直流输电系统换相失败判别结果的正确性。 相似文献