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21.
本拟设计了一种用于汽车挡风玻璃上的自动雨点检测器及刮雨器控制装置,其原理利用了挡风玻璃中的光波导作用,并经模拟实验证实此方案可行。  相似文献   
22.
Photomorphogenic responses of etiolated seedlings include the inhibition of hypocotyl elongation and opening of the apical hook. In addition, dark-grown seedlings respond to light by the formation of adventitious roots (AR) on the hypocotyl. How light signaling controls adventitious rooting is less well understood. Hereto, we analyzed adventitious rooting under different light conditions in wild type and photomorphogenesis mutants in Arabidopsis thaliana. Etiolation was not essential for AR formation but raised the competence to form AR under white and blue light. The blue light receptors CRY1 and PHOT1/PHOT2 are key elements contributing to the induction of AR formation in response to light. Furthermore, etiolation-controlled competence for AR formation depended on the COP9 signalosome, E3 ubiquitin ligase CONSTITUTIVELY PHOTOMORPHOGENIC (COP1), the COP1 interacting SUPPRESSOR OF PHYA-105 (SPA) kinase family members (SPA1,2 and 3) and Phytochrome-Interacting Factors (PIF). In contrast, ELONGATED HYPOCOTYL5 (HY5), suppressed AR formation. These findings provide a genetic framework that explains the high and low AR competence of Arabidopsis thaliana hypocotyls that were treated with dark, and light, respectively. We propose that light-induced auxin signal dissipation generates a transient auxin maximum that explains AR induction by a dark to light switch.  相似文献   
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Although light-emitting diode (LED) technology has extended the research on targeted photomorphogenic, physiological, and biochemical responses in plants, there is not enough direct information about how light affects polyamine metabolism. In this study, the effect of three spectral compositions (referred to by their most typical characteristic: blue, red, and the combination of blue and red [pink] lights) on polyamine metabolism was compared to those obtained under white light conditions at the same light intensity. Although light quality induced pronounced differences in plant morphology, pigment contents, and the expression of polyamine metabolism-related genes, endogenous polyamine levels did not differ substantially. When exogenous polyamines were applied, their roborative effect were detected under all light conditions, but these beneficial changes were correlated with an increase in polyamine content and polyamine metabolism-related gene expression only under blue light. The effect of the polyamines on leaf gene expression under red light was the opposite, with a decreasing tendency. Results suggest that light quality may optimize plant growth through the adjustment of polyamine metabolism at the gene expression level. Polyamine treatments induced different strategies in fine-tuning of polyamine metabolism, which were induced for optimal plant growth and development under different spectral compositions.  相似文献   
27.
介绍了国家标准GB 7000.217-2008/IEC 60598-2-17:1984+A2:1990《灯具第2-17部分:特殊要求舞台灯光、电视、电影及摄影场所(室内外)用灯具》的特殊要求,阐述了对该标准特殊要求条文的理解和解释以及其对LED舞台灯具的适用性,以帮助舞台灯具行业的设计、生产、检验和使用人员正确理解和应用舞台灯具国家标准。  相似文献   
28.
通常,电光源在室内照明时会产生热量,并对人体的热舒适产生一定的影响;同时,室内光源色温的变化会引起人们在心理上对热环境感受的差异.有些住宅由于灯光组合设计单一, 住户在夏季最炎热时,往往减少室内照明电光源的开启数量达到舒适要求,从而降低了室内的照度,影响了光环境的质量;由于灯光设计缺乏足够的应变功能,到了家庭团聚、会客或冬季较冷的时候又会感到灯光有些昏暗.因而,建立和谐的光和热建筑物理环境,不仅应达到生理上的舒适,还应注意心理舒适的特殊要求.  相似文献   
29.
研究了注碳外延硅经氢气退火及电化学腐蚀处理后的荧光特性。经能量为50keV,剂量为2×1016cm-2的碳离子注入后的外延单晶硅片,在氢气氛下高温退火及电化学腐蚀处理。荧光谱仪分析表明电化学腐蚀是蓝光发射的前提,并且不同的电化学腐蚀条件对发光强度和峰位影响极大。不同的激发光波长亦可影响发光谱的峰位。  相似文献   
30.
Recent advances in optical clearing techniques have dramatically improved deep tissue imaging by reducing the obscuring effects of light scattering and absorption. However, these optical clearing methods require specialized equipment or a lengthy undertaking with complex protocols that can lead to sample volume changes and distortion. In addition, the imaging of cleared tissues has limitations, such as fluorescence bleaching, harmful and foul-smelling solutions, and the difficulty of handling samples in high-viscosity refractive index (RI) matching solutions. To address the various limitations of thick tissue imaging, we developed an Aqueous high refractive Index matching and tissue Clearing solution for Imaging (termed AICI) with a one-step tissue clearing protocol that was easily made at a reasonable price in our own laboratory without any equipment. AICI can rapidly clear a 1 mm thick brain slice within 90 min with simultaneous RI matching, low viscosity, and a high refractive index (RI = 1.466), allowing the imaging of the sample without additional processing. We compared AICI with commercially available RI matching solutions, including optical clear agents (OCAs), for tissue clearing. The viscosity of AICI is closer to that of water compared with other RI matching solutions, and there was a less than 2.3% expansion in the tissue linear morphology during 24 h exposure to AICI. Moreover, AICI remained fluid over 30 days of air exposure, and the EGFP fluorescence signal was only reduced to ~65% after 10 days. AICI showed a limited clearing of brain tissue >3 mm thick. However, fine neuronal structures, such as dendritic spines and axonal boutons, could still be imaged in thick brain slices treated with AICI. Therefore, AICI is useful not only for the three-dimensional (3D) high-resolution identification of neuronal structures, but also for the examination of multiple structural imaging by neuronal distribution, projection, and gene expression in deep brain tissue. AICI is applicable beyond the imaging of fluorescent antibodies and dyes, and can clear a variety of tissue types, making it broadly useful to researchers for optical imaging applications.  相似文献   
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