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991.
近年来,蓝光对人眼的危害逐渐被人们所认识和关注。蓝光危害风险不仅存在于照明光源中,还存在于显示产品中。减少蓝光的含量是降低蓝光危害的直接方法。而蓝光是显示产品光谱中必不可少的组成波段,同时也是满足显示产品色温和色域需求,完美展现丰富多彩的真实世界的必需颜色。因此如何在不降低正常显示标准下,发展抗蓝光危害的技术是显示技术的一个重要研究方向。目前,国内外众多研究者围绕蓝光生物安全性及防蓝光显示技术进行了较深入的研究。本文首先阐述了蓝光危害的作用机制、危害分类和评估方法、标准,分析了显示产品中影响蓝光危害程度的多种影响因素。介绍了目前防蓝光显示技术新进展,并对防蓝光显示技术进展进行了总结和展望。 相似文献
992.
993.
Hongchao Li Yanhou Geng Shuwen Tong Hui Tong Rong Hua Guangping Su Lixiang Wang Xiabin Jing Fosong Wang 《Journal of polymer science. Part A, Polymer chemistry》2001,39(19):3278-3286
A series of light‐emitting poly(p‐phenylene vinylene)s with triphenylamine units as hole‐transporting moieties in the main chain were synthesized via Wittig condensation in good yields. The newly formed vinylene double bonds possessed a trans configuration, which was confirmed by Fourier transform infrared and NMR spectroscopy. The high glass‐transition temperature (83–155 °C) and high decomposition temperature (>300 °C) suggested that the resulting copolymers possessed high thermal stability. These copolymers, especially TAAPV1, possessed a high weight‐average molecular weight (47,144) and a low polydispersity index (1.55). All the copolymers could be dissolved in common organic solvents, such as tetrahydrofuran (THF), CHCl3, CH2Cl2, and toluene, and exhibited intense photoluminescence in THF (the emission maxima were located from 478 to 535 nm) and in film (from 478 to 578 nm). The low onsets of the oxidation potential (0.6–0.75 V) suggested that the alternating copolymers possessed a good hole‐transporting property due to the incorporation of triphenylamine moieties. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3278–3286, 2001 相似文献
994.
正向设计了一种适合于听觉神经刺激的可编程双相恒流脉冲发生器,它可根据耳聋患者的要求和不同的语音信号,控制刺激电流脉冲的幅度和宽度,以及脉冲之间的间隙。本文阐述了电路的设计要求和方法,并给出了实验结果。采用标准3μmp阱CMOS工艺,在上海贝岭微电子制造有限公司流片。目前已成功地用于多道人工电子耳蜗接收刺激器中。 相似文献
995.
Emilio Celotti Georgios Lazaridis Jakob Figelj Yuri Scutaru Andrea Natolino 《Molecules (Basel, Switzerland)》2022,27(1)
The oxidation processes of white wines can occur during storage and commercialization due to several factors, and these can negatively affect the color, aroma, and quality of the wine. Wineries should have faster and simpler methods that provide valuable information on oxidation stability of wines and allow fast decision-making procedures, able to trigger suitable technological interventions. Using a portable prototype instrument for light irradiations at different wavelengths and times was considered and evaluated on sensorial, spectrophotometric, and colorimetric parameters of white wines. The sensorial analysis revealed that white and light blue were the most significant, after only 1 h of irradiation. The experimental results showed that hydrogen peroxide could enhance the effect of light treatment, allowing a contemporary evaluation of the oxidation stability of wine against light and chemical stresses. As expected, a good correlation (R2 > 0.89) between optical density at 420 nm and b* parameter was highlighted. The synergic effect of light and H2O2 was also studied on the hydrolyzable and condensed tannins’ additions to white wine. The proposed methodology could be used to evaluate the oxidative stability of white wines, but also to evaluate the effect of some oenological adjuvants on wine stability. 相似文献
996.
Reconstruction and interpretation of photon Doppler velocimetry spectrum for ejecta particles from shock-loaded sample in vacuum 下载免费PDF全文
《中国物理 B》2021,30(6):66201-066201
The photon Doppler velocimetry(PDV) spectrum is investigated in an attempt to reveal the particle parameters of ejecta from shock-loaded samples in a vacuum. A GPU-accelerated Monte–Carlo algorithm, which considers the multiplescattering effects of light, is applied to reconstruct the light field of the ejecta and simulate the corresponding PDV spectrum.The influence of the velocity profile, total area mass, and particle size of the ejecta on the simulated spectra is discussed qualitatively. To facilitate a quantitative discussion, a novel theoretical optical model is proposed in which the singlescattering assumption is applied. With this model, the relationships between the particle parameters of ejecta and the peak information of the PDV spectrum are derived, enabling direct extraction of the particle parameters from the PDV spectrum.The values of the ejecta parameters estimated from the experimental spectrum are in good agreement with those measured by a piezoelectric probe. 相似文献
997.
In recent years, spatial self-phase modulation (SSPM) with two-dimensional (2D) materials has attracted the attention of many researchers as an emerging and ubiquitous nonlinear optical effect. In this review, the state of the art of 2D material-based SSPM is summarized. SSPM measures or tunes the nonlinearity of 2D materials, and it is also an effective approach to study the band structure of 2D materials. Several modified forms of SSPM, such as high-order, white-light-excited, vector field excited, and optically nonlinearly enhanced SSPM are also presented. Subsequently, the physical origin of the SSPM formation mechanism is compared and analyzed. Furthermore, the applications of SSPM with 2D materials, including passive photonic devices, generation of Bessel beams, and identifying the mode of the orbital angular momentum, are listed. Finally, several urgent problems of the SSPM with 2D materials, potential applications, and prospects for future development are presented. 相似文献
998.
在不断增长的液晶显示(LCD)优势中,电润湿的新技术正试图在较好的光线利用和简化制造方面,占据一席之地。 相似文献
999.
1000.