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基于二次虚拟光源的实时间接光照
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作者 乔侃 《科技传播》 2011年第21期198-198,188,共2页
本文提出了一种动态场景中漫反射表面的实时间接光照计算方法。该方法使用反射阴影图(RSM)来生成虚二次拟点光源(VPLs),并利用光强度体(自定义的一个用于存储光照强度的一个数据结构)和球谐系数来表示场景中VPL光照的分布信息,最后使用... 本文提出了一种动态场景中漫反射表面的实时间接光照计算方法。该方法使用反射阴影图(RSM)来生成虚二次拟点光源(VPLs),并利用光强度体(自定义的一个用于存储光照强度的一个数据结构)和球谐系数来表示场景中VPL光照的分布信息,最后使用延迟渲染技术来渲染整个场景。整个过程不需要预计算,并能在当前主流GPU上满足实时渲染的要求。 展开更多
关键词 次虚拟光源 实时间 接光照
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二次序列闪光高速照相系统研究 被引量:1
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作者 罗红娥 陈平 +2 位作者 顾金良 夏言 栗保明 《光学技术》 CAS CSCD 北大核心 2009年第5期759-760,765,共3页
首次提出二次序列闪光高速照相系统结构。利用二次序列闪光激光光源在CCD相机曝光时间内两次发出超短激光脉冲,实现在一幅图像中捕获两个不同位置处高速运动目标图像。此系统可实现在一个照相站内两次成像,相当于实现两个照相站的功能,... 首次提出二次序列闪光高速照相系统结构。利用二次序列闪光激光光源在CCD相机曝光时间内两次发出超短激光脉冲,实现在一幅图像中捕获两个不同位置处高速运动目标图像。此系统可实现在一个照相站内两次成像,相当于实现两个照相站的功能,在现代弹道测量中有广泛的应用前景。 展开更多
关键词 光学技术 高分辨率CCD正交照相系统 次序列闪光激光光源 次成像
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LED汽车大灯光源设计方案探讨 被引量:3
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作者 关春安 冯建伟 《南阳理工学院学报》 2011年第2期22-25,共4页
针对汽车LED光源存在的固有耐温性能差等问题,根据汽车大灯的实际工况,阐明了汽车大灯LED光源设计的一般要求。通过对一单芯XlampLED在汽车大灯设计中应用案例的分析,就LED光源的安全措施,提出了二光源模板分散发热体布局和循环散热的... 针对汽车LED光源存在的固有耐温性能差等问题,根据汽车大灯的实际工况,阐明了汽车大灯LED光源设计的一般要求。通过对一单芯XlampLED在汽车大灯设计中应用案例的分析,就LED光源的安全措施,提出了二光源模板分散发热体布局和循环散热的解决方案。同时,设计了汽车大灯的LED光源模块应用电路,改进了LED汽车大灯的转向偏光机构等辅助功能。方案为实现汽车大灯的机电一体化和智能化控制,以及为汽车大灯的开发应用提供了一个新的思路。 展开更多
关键词 汽车大灯 LED光源 二光源 随动部件
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辐射源、光源
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《中国光学》 EI CAS 1995年第2期4-4,共1页
TM923.01 95020712狭缝和矩形光阑对频谱的影响=The effect ofreetangular an sIit aperture on the spectrumof partially coherent light[刊,中]/王中阳,林强,王绍民(杭州大学物理系.浙江,杭州(310028))
关键词 大学物理 光源 圆形光阑 频谱 狭缝 辐射源 杭州 浙江 中阳 矩形和
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试论电视教材的室内用光
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作者 夏仁康 《中国医学教育技术》 1989年第1期39-41,共3页
有人说:摄影是用光作画。光如同画家手中的画笔和颜料,在照明工作者手里可以用它“画”出一幅幅美丽的画面。照明与布光对于提高电视教材的艺术感染力有着极其重要的怍用。在一些专业厂家和电视台,照明工作有专业人员,但学校视听教育机... 有人说:摄影是用光作画。光如同画家手中的画笔和颜料,在照明工作者手里可以用它“画”出一幅幅美丽的画面。照明与布光对于提高电视教材的艺术感染力有着极其重要的怍用。在一些专业厂家和电视台,照明工作有专业人员,但学校视听教育机构,由于人员、设备、规模等多方面的限制,大部分都没有专职的照明人员,而是由摄影。 展开更多
关键词 电视教材 视听教育 专业厂家 艺术感染力 布光 彩色还原 光源 摄象机 混合光 平均亮度
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Driving Circuit for AMOLED with Fault Tolerance
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作者 李大勇 刘明 Wei Wang 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第9期1337-1340,共4页
The defects of an OLED-based display,mainly electrical shorts,cause pixels to stay dark,decrease the brightness of a panel,severely influence the display uniformity,and also consume a considerable amount of power. In ... The defects of an OLED-based display,mainly electrical shorts,cause pixels to stay dark,decrease the brightness of a panel,severely influence the display uniformity,and also consume a considerable amount of power. In this paper, for AM-OLEDs, a novel circuit employing p-type low-temperature poly-Si thin-film transistors is introduced to offer fault-tolerant capabilities for such defects. The results show that this circuit can save significant power and maintain the luminance of the pixel without changing the driving current. 展开更多
关键词 organic light-emitting diode active matrix OLED fault tolerance
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电视教材制作照明浅论
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作者 张飞天 《电化教育研究》 1985年第3期52-56,共5页
在电视教材的制作过程中,照明是前期录制中的重要环节,而这个环节往往被轻视。光线处理得好坏直接影响彩色画面的色调、层次和清晰度。光是照明人员通过各种处理手段来表现教学内容和艺术效果的,决不是一种简单的开灯和关灯工作。有人... 在电视教材的制作过程中,照明是前期录制中的重要环节,而这个环节往往被轻视。光线处理得好坏直接影响彩色画面的色调、层次和清晰度。光是照明人员通过各种处理手段来表现教学内容和艺术效果的,决不是一种简单的开灯和关灯工作。有人曾作过这样的比喻:'照明就是用光在屏幕上绘画'。下面就电视教材制作中的照明问题作一浅论。 展开更多
关键词 电视教材 摄象机 光源 布光 能量分布 调光器 混合光 色温表 中央电化教育馆 一次光源
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Development and Practical Applications of Blue Light-Emitting Diodes 被引量:1
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作者 Hideaki Koizumi 《Engineering》 SCIE EI 2015年第2期167-168,共2页
The practical application of semiconductor-based high-efficiency white-light sources, also known as light-emitting diodes, or LEDs, is a recent development of Japanese engineering. This development could be a game-cha... The practical application of semiconductor-based high-efficiency white-light sources, also known as light-emitting diodes, or LEDs, is a recent development of Japanese engineering. This development could be a game-changer for lighting worldwide, given that current power consumption for lighting accounts for 16% of the total electricity consumption in Japan. 展开更多
关键词 salinity gradient energy pressure-retarded osmosis reverses electrodialysis
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Structure of Protonated Heterodimer of Proline and Phenylalanine:Revealed by Infrared Multiphoton Dissociation Spectroscopy and Theoretical Calculations 被引量:1
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作者 Juan Ren Xian-yi Zhang Xiang-lei Kong 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第5期590-594,I0029-I0038,I0079,共16页
The infrared multiphoton dissociation(IRMPD)spectrum of the protonated heterodimer of Pro Phe H+,in the range of 2700-3700 cm^-1,has been obtained with a Fourier-transform ion cyclotron mass spectrometer combined with... The infrared multiphoton dissociation(IRMPD)spectrum of the protonated heterodimer of Pro Phe H+,in the range of 2700-3700 cm^-1,has been obtained with a Fourier-transform ion cyclotron mass spectrometer combined with an IR OPO laser.The experimental spectrum shows one peak at 3565 cm^-1 corresponding to the free carboxyl O-H stretching vibration,and two broad peaks centered at 2935 and 3195 cm^-1.Theoretical calculations were performed on the level of M062 X/6-311++G(d,p).Results show that the most stable isomer is characterized by a charge-solvated structure in which the proton is bound to the unit of proline.Its predicted spectrum is in good agreement with the experimental one,although the coexistence of salt-bridged structures cannot be entirely excluded. 展开更多
关键词 Infrared multiphoton dissociation spectroscopy Mass spectrometry HETERODIMER Amino acids
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成绩斐然的韩国城市建设
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作者 晓月 《学习月刊》 2016年第1期28-29,共2页
韩国位于朝鲜半岛南部,东濒日本海,西临我国黄海,东南与日本隔海相望。国土面积占半岛总面积的45%,约99000平方公里;韩国人口众多,近4300万,是世界上人口密度最大的地区之一,而自然资源又相当贫乏,至今为止,没有发现任何有开采价值的石... 韩国位于朝鲜半岛南部,东濒日本海,西临我国黄海,东南与日本隔海相望。国土面积占半岛总面积的45%,约99000平方公里;韩国人口众多,近4300万,是世界上人口密度最大的地区之一,而自然资源又相当贫乏,至今为止,没有发现任何有开采价值的石油和煤炭等能源基地,其他有经济价值的矿产也寥寥无几。如此地理环境,并没有影响韩国经济的快速发展。自上世纪60、70年代起,他们就打开国门,扬长避短,逐步优化了国家经济链,使城市建设得到了较快发展。 展开更多
关键词 开采价值 能源基地 朝鲜半岛 城市建设 国土面积 高档轿车 汉城市 卫星城镇 光源 起亚
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半导体领军“绿色照明”时代
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作者 陈颖健 《国外科技动态》 2004年第7期10-11,共2页
众所周知,半导体已在电子领域完成了一次革命,而另一次革命将发生在照明领域。节能和环保是未来工业发展的主流,半导体照明在节能,环保方面极具发展潜力。
关键词 半导体照明 使用寿命 投资费用 光源
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Photo Degradation of Dyes from Their Aqueous Solutions of Their Binary Mixture, Using TiO2 as the Oxidant with Different Sources of Energy
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作者 S. Shanthi K. Sathya Priya 《Journal of Chemistry and Chemical Engineering》 2012年第10期951-955,共5页
The photodegradation has been widely used in water and waste water treatment of all the methods like froth flotation coagulation etc., photodegradation appears to offer the best prospects for overall treatment of dyes... The photodegradation has been widely used in water and waste water treatment of all the methods like froth flotation coagulation etc., photodegradation appears to offer the best prospects for overall treatment of dyestuff effulent. Photodegradation of aniline blue and crystal violet dyes from aqueous solutions of their binary mixture was carried out using TiO2 as photocatalyst. By carrying out photodegradation, varying the experimental parameters, the optimum conditions required for maximum degradation was found out. The photodegradation of dye was carried out using different sources of energy like solar radiation and microwave radiation. The degradation studies were carried out at temperatures 25 ℃, 35 ℃ and 45 ℃ so as to calculate the rate constant and activation parameters. Both energy sources are equivalent in causing degradation in all respects except time and dose of photo catalyst. Time required is less for microwave than solar radiation, but dose of photo catalyst needed was high for microwave radiation. These results will be helpful in designing effluent treatment plants in industries. 展开更多
关键词 Photo degradation semi conductor crystal violet aniline blue mixture of dyes TiO2.
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Bon Appetit! An Investigation About the Best and Worst Color Combinations of Lighting and Food
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作者 Hyeon-Jeong Suk Geun-Ly Park Yoonsook Kim 《Journal of Literature and Art Studies》 2012年第5期559-566,共8页
We investigated an interaction effect between lighting color and food color that stimulates or discourages one's appetite. Facilitated by the LED (light-emitting diode) as an additional chromatic lighting source, o... We investigated an interaction effect between lighting color and food color that stimulates or discourages one's appetite. Facilitated by the LED (light-emitting diode) as an additional chromatic lighting source, observers selected the best and worst lighting colors by themselves using a "Mini Living Colors (PhilipsTM)" in the preliminary test (N = 30) and then color picker software in the main experiment (N = 30). Food stimuli were composed of two aspects, type--natural or processed--and complexity--low or high, and consequently they were grouped into four categories. We measured the selected lighting color in terms of chromaticity and illumination level, and analyzed the best and worst combinations based on these measurements. Throughout the two empirical studies, we found three tendencies: First, except for the white, yellow lighting stimulates while red and blue discourages one's appetite. Second, when color categories of lighting and food are similar to each other, it stimulates the appetite whereas complementary, it discourages it. Third, the type of food does not act as an influencing factor. 展开更多
关键词 food color lighting color APPETITE COLOR
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Interfacial engineering of graphitic carbon nitride(g-C_3N_4)-based metal sulfide heterojunction photocatalysts for energy conversion: A review 被引量:36
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作者 Yijie Ren Deqian Zeng Wee-Jun Ong 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第3期289-319,共31页
As one of the most appealing and attractive technologies, photocatalysis is widely used as a promising method to circumvent the environmental and energy problems. Due to its chemical stability and unique physicochemic... As one of the most appealing and attractive technologies, photocatalysis is widely used as a promising method to circumvent the environmental and energy problems. Due to its chemical stability and unique physicochemical, graphitic carbon nitride (g-C3N4) has become research hotspots in the community. However, g-C3N4 photocatalyst still suffers from many problems, resulting in unsatisfactory photocatalytic activity such as low specific surface area, high charge recombination and insufficient visible light utilization. Since 2009, g-C3N4-based heterostructures have attracted the attention of scientists worldwide for their greatly enhanced photocatalytic performance. Overall, this review summarizes the recent advances of g-C3N4-based nanocomposites modified with transition metal sulfide (TMS), including (1) preparation of pristine g-C3N4,(2) modification strategies of g-C3N4,(3) design principles of TMS-modified g-C3N4 heterostructured photocatalysts, and (4) applications in energy conversion. What is more, the characteristics and transfer mechanisms of each classification of the metal sulfide heterojunction system will be critically reviewed, spanning from the following categories:(1) Type I heterojunction,(2) Type II heterojunction,(3) p-n heterojunction,(4) Schottky junction and (5) Z-scheme heterojunction. Apart from that, the application of g-C3N4-based heterostructured photocatalysts in H2 evolution, CO2 reduction, N2 fixation and pollutant degradation will also be systematically presented. Last but not least, this review will conclude with invigorating perspectives, limitations and prospects for further advancing g-C3N4-based heterostructured photocatalysts toward practical benefits for a sustainable future. 展开更多
关键词 Graphitic carbon nitride Metal sulfide PHOTOCATALYSIS Energy transformation Water splitting Reduction of carbon dioxide Pollutant degradation Nitrogen fixation
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Multichip on Aluminum Metal Plate Technology for High Power LED Packaging
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作者 Choong-mo NAM Mi-hee JI 《Journal of Measurement Science and Instrumentation》 CAS 2010年第3期297-299,共3页
Multichip on Ahnnintnn Metal Plate(MOAMP) technology with simple structure and low thermal resistance is developed for effective heat reratrval of Light Emitting Diode(LED) p-n junction and LED lighting module to ... Multichip on Ahnnintnn Metal Plate(MOAMP) technology with simple structure and low thermal resistance is developed for effective heat reratrval of Light Emitting Diode(LED) p-n junction and LED lighting module to have high reliability. The thermal resistance of LED modules was numerical and experimental. Thermal resistance from the jtnction to aluminten metal plate, considering input power of IFD module using MOAMP technology, is 3.02 K/W, 3.23 K/W for the measured and calculated, respectively. We expect that the reported MOAMP technology with low thermal resistance will be a promising solution for high power LED fighting modules. 展开更多
关键词 - thermal resistance Light Emitting Diode (IFO) aluminum metal plate IHOAMP
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Power management unit chip design for automobile active-matrix organic light-emitting diode display module 被引量:4
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作者 KIM J H PARK J H +7 位作者 KIM J H CAO T V LEE T Y BAN H J YANG K KIM H G HA P B KIM Y H 《Journal of Central South University》 SCIE EI CAS 2009年第4期621-628,共8页
A power management unit (PMU) chip supplying dual panel supply voltage, which has a low electro-magnetic interference (EMI) characteristic and is favorable for miniaturization, is designed. A two-phase charge pump... A power management unit (PMU) chip supplying dual panel supply voltage, which has a low electro-magnetic interference (EMI) characteristic and is favorable for miniaturization, is designed. A two-phase charge pump circuit using external pumping capacitor increases its pumping current and works out the charge-loss problem by using bulk-potential biasing circuit. A low-power start-up circuit is also proposed to reduce the power consumption of the band-gap reference voltage generator. And the ring oscillator used in the ELVSS power circuit is designed with logic devices by supplying the logic power supply to reduce the layout area. The PMU chip is designed with MagnaChip's 0.25 μ high-voltage process. The driving currents of ELVDD and ELVSS are more than 50 mA when a SPICE simulation is done. 展开更多
关键词 DC-DC converter AMOLED charge pumping power management unit (PMU) dual panel supply voltage
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Comparison of Solar Trackers and Application of a Sensor Less Dual Axis Solar Tracker
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作者 Ceyda Aksoy Tirmikci Cenk Yavuz 《Journal of Energy and Power Engineering》 2015年第6期556-561,共6页
In the 21th century, one of the biggest problems that the world faces is energy provision. Today, the way that most countries use for energy production is not clean and continuous. The most obvious proof for that is t... In the 21th century, one of the biggest problems that the world faces is energy provision. Today, the way that most countries use for energy production is not clean and continuous. The most obvious proof for that is the change in the climate. The amount of CO2 (carbon dioxide) that is caused by fossil fuel burning increases day by day and this situation creates the greenhouse effect and change in the climate. The sun is one of the best solutions to this problem. It is not only clean and continuous, but also available anywhere, anytime. However, the efficiency of a photovoltaic system is directly related to the amount of solar energy acquired by the system which means that, it is necessary to follow the sun to have a high efficient system. There are two types of trackers that follow the sun and there are several ways to build them. In this paper, solar tracker designs are examined and a new dual axis solar tracker design is given. 展开更多
关键词 Solar energy sensorless solar tracker solar math linear actuators efficiency low cost.
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Transcriptional and translational responses of rapeseed leaves to red and blue lights at the rosette stage
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作者 Sheng-xin CHANG Chu PU +2 位作者 Rong-zhan GUAN Min PU Zhi-gang XU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2018年第8期581-595,共15页
Under different red (R):blue (B) photon flux ratios, the growth performance of rapeseed (Brassica napus L.) is significantly different. Rapeseed under high R ratios shows shade response, while under high B rati... Under different red (R):blue (B) photon flux ratios, the growth performance of rapeseed (Brassica napus L.) is significantly different. Rapeseed under high R ratios shows shade response, while under high B ratios it shows sun-type morphology. Rapeseed under monochromatic red or blue light is seriously stressed. Transcriptomic and proteomic methods were used to analyze the metabolic pathway change of rapeseed (cv. "Zhongshuang 11") leaves under different R:B photon flux ratios (including 100R:0B%, 75R:25B%, 25R:75B%, and 0R:100B%), based on digital gene expression (DGE) and two-dimensional gel electrophoresis (2-DE). For DGE analysis, 2054 differentially expressed transcripts (llog2(fold change)l〉1, q〈0.005) were detected among the treatments. High R ratios (100R:0B% and 75R:25B%) enhanced the expression of cellular structural components, mainly the cell wall and cell membrane. These components participated in plant epidermis development and anatomical structure morphogenesis. This might be related to the shade response induced by red light. High B ratios (25R:75B% and 0R:100B%) promoted the expression of chloroplast-related components, which might be involved in the formation of sun-type chloroplast induced by blue light. For 2-DE analysis, 37 protein spots showed more than a 2-fold difference in expression among the treatments. Monochromatic light (ML; 100R:0B% and OR: 100B%) stimulated accumulation of proteins associated with antioxidation, photosystem II (PSII), DNA and ribosome repairs, while compound light (CL; 75R:25B% and 25R:75B%) accelerated accumulation of proteins associated with carbohydrate, nucleic acid, amino acid, vitamin, and xanthophyll metabolisms. These findings can be useful in understanding the response mechanisms of rapeseed leaves to different R:B photon flux ratios. 展开更多
关键词 Brassica napus L. Light emitting diode (LED) light Comparative transcdptome and proteome Leaf morphogenesis Stress response
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The improved performance in the ternary bulk heterojunction solar cells 被引量:1
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作者 QIN DaShan LI GuiFang +4 位作者 QUAN Wei CHEN Lei LIU JinSuo ZHANG JiDong YAN DongHang 《Science China Chemistry》 SCIE EI CAS 2013年第3期530-534,共5页
The ternary blend films have been fabricated via adding 4,4'-N,N'-dicarbazole-biphenyl(CBP,a hole transport material widely used in organic light emitting diodes) into the poly(3-hexylthiophene):[6,6]-phenyl C... The ternary blend films have been fabricated via adding 4,4'-N,N'-dicarbazole-biphenyl(CBP,a hole transport material widely used in organic light emitting diodes) into the poly(3-hexylthiophene):[6,6]-phenyl C 61-butyric acid methyl ester(P3HT:PCBM).Despite the wide bandgap(3.1 eV) of the CBP,the solar cell utilizing the optimized P3HT:PCBM:CBP blend film showed an increase of 16% in power conversion efficiency and 25% in short-circuit current than the compared standard P3HT:PCBM blend film.This is attributed to the fact that the addition of the CBP could enhance the aggregation of the P3HT chains and thereby reduce the hole-electron recombination at the interface of P3HT and PCBM.We provide a simple,effective way to improve the performance of P3HT based bulk heterojunction solar cells. 展开更多
关键词 bulk heterojunction organic solar cells ternary blend films CBP
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家庭影院屏幕上的光学常识
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作者 赵娜丽 《家庭影院技术》 1998年第8期45-47,共3页
什么是光通量物理教科书上把光源在单位时间内向周围空间发射能够让人看得见的那部分辐射能量的总和称为光通量,用符号Φ表示,单位叫做流明(lm)。光源在单位立体角ω里所产生的光通量叫做发光强度I,单位为坎德拉(cd)。
关键词 光通量 家庭影院 屏幕增益 照度 发光强度 光源 坎德拉 立体角 流明 亮度
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