LED白光源用Pr^(3+),Ce^(3+):YAG光纤制备与特性

采用激光加热基座法制备LED白光源用Pr3+,Ce3+:YAG单晶光纤荧光材料,对所制备材料的荧光光学特性进行了实验分析结果表明,在Pr3+和Ce3+共掺发光过程中,Pr3+离子的发光可以通过Ce3+敏化作用使得其610nm谱线荧光强度得到有效增强;利用所制备Pr3+,Ce3+:YAG单晶光纤荧光材料与蓝色LED合成产生高效LED光纤白光源,光源的色坐标为(x=0.322,y=0.335),显色指数84.3,表明光源品质良好,有望用于未来高效大功率光纤白光源.

带状白光源再现彩虹全息象的象差模型

给出了带状白光源再现彩虹全息象的象差模型:带源上每点的“有效光谱范围”引起象点的相同的横向位移(或垂直于狭缝长方向的位移);带源上各点的“有效中心波长”引起象点的纵向色差(或沿着眼的视线方向的轴向色散).利用所给公式算出了相应的允许象距.此象差模型有助于揭示彩虹全息消色差的物理本质,对于光路设计中参数的先择有实际意义。

冷光源美白治疗的护理

目的:探讨冷光源美白治疗的护理方法。方法:对43例牙齿变色患者进行冷光源美白治疗,做好术前交流和准备工作,术中与医生密切配合,并加强术后的心理护理。结果:43例不同类型的变色牙经冷光源美白治疗后的有效率为100%;三组间比较无显著性差异,显效率比较,增龄性黄牙组与氟斑牙组比较有显著性差异,增龄性黄牙组与四环素牙组相比有显著性差异,氟斑牙组与四环素牙组相比有显著性差异。治疗中及术后有17例患者出现不同程度的敏感症状,3天后症状消失。结论:冷光源美白治疗是一种快捷、安全有效的治疗手段,治疗前与患者交流、术中护理配合和术后心理护理是治疗成功的保障。

一种节能白光面光源仪的设计及应用

目前高校大学物理光学实验采用的日光台灯、白炽灯等光源不仅耗能很大而且实验中经常出现漏光、像散、像移、成像质量差、调节不方便等问题,对实验的结果影响很大。针对此问题,将民用节能日光灯管用于实验仪器上,设计了一种节能白光面光源仪。该节能白光面光源仪作为"用分光计测棱镜玻璃的折射率"、"用透射光栅测定光波波长"、"迈克尔逊干涉仪的使用"和"薄透镜焦距的测定"等多个大学物理光学实验的光源,可有效地提高实验效果及效率。

白光LED驱动方案

本文介绍了驱动白光LED的方案和典型应用电路。

基于气炼法Yb^(2+)/Yb^(3+)共掺石英玻璃制备及光谱特性的研究

提出利用气炼法制备Yb^(2+)/Yb^(3+)共掺石英玻璃,通过增加辅助加热装置来控制Yb^(3+)和Yb^(2+)离子间的转化过程,并对不同条件下制备的Yb^(2+)/Yb^(3+)共掺石英玻璃的吸收特性和发射特性进行了研究。由于Yb2+离子的4f^(14)→4f^(13) 5d能级跃迁,经过辅助加热制备的Yb^(2+)/Yb^(3+)共掺石英玻璃有着更强的吸收强度和更多的吸收峰,并且其吸收光谱的尾部向更长波长延伸,同时也可观察到Yb^(3+)离子典型的吸收特性。经过辅助加热制备的Yb^(2+)/Yb^(3+)共掺石英玻璃的主发射峰位于530 nm左右,经色作标换算得到所制备玻璃的色坐标为(0.332 2,0.476 7),落在白光区域。研究结果表明,所制备的Yb^(2+)/Yb^(3+)共掺石英玻璃是一种白光LED的潜在材料。

用瑞利干涉仪测空气折射率

用瑞利干涉仪测量空气在不同压强下的折射率要注意除回程误差,本文提出几种消除回程误差的方法。 原理如图1,A为光源,L1、L2为凸透镜。T1、T2是长度相同（L=10cm）的两根玻璃管。C、D为性质相同的两玻璃块,称为补偿器调节转盘（未画出）可使D偏转一定角度,E为视场屏幕。

Development and Practical Applications of Blue Light-Emitting Diodes

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.

Efficient production of transgenic chickens using self-inactive HIV-based lentiviral vectors

We demonstrated the simple and effective production of transgenic chickens, in which the enhanced green fluorescence protein （EGFP） was expressed by using third-generation self-inactive HIV-based lentiviral vectors. In our experiments, lentiviruses were injected into 204 fertilized eggs, from which 30 （15%） chickens were hatched. The exogenous gene was detected in the genomes of 16 out of 30 （53%） chickens. The green fluorescence signal was observed directly in various body parts, and was particularly significant in the testes. The transgenes were also found in the offspring of these chickens. The results indicate that HIV-based lentiviral vectors can be used to generate transgenic birds economically and effectively [ Current Zoology 55 （5）： 383 - 387,2009].

A Viral Expression Vector from Foxtail mosaic virus to Express Green Fluorescent Protein

[Objective]Foxtail mosaic virus(FoMV)infects gramineous and dicotyledonous plants.In this study,we sought to construct a viral vector based on FoMV to express exogenous proteins in plants.[Method]A recombinant viral expression vector was constructed by inserting the promotor of Potato virus X(PVX)and exogenous gene sequences into the 3’non-coding region of the FoMV coat protein gene.[Results]The plasmid pCB301-FoMV-CP-PVXprom-GFP expressed green fluorescent protein in inoculated Nicotiana benthamiana leaves.[Conclusion]A recombinant viral expression vector was constructed successfully.

Calculation and Simulation Design of a Novel LED Light

Presented is a convenient and timesaving design method for illuminating light being used as a pint-sized searchlight usually,based on white light emitting diode(LED) source.The process of design is studied mostly in advanced system analysis program(ASAP).The analyses on this kind of design method reveal the factors that would affect the luminous flux distribution of light,including the number of LED chips,the focus of reflecor and refractor,the corresponding position of reflector and refractor with the source.The zone cofficient method and point-by point method are discussed respectively to determine the LED source and the illuminace distribution of light.The desired parallel light output is gained after being optimized in ASAP at last.

Responses of Hyalella Azteca to Chronic Exposure of Mississippi Delta Sediments

Hyalella azteca was used to assess biological impairment in sediments from nine water bodies in the Mississippi Delta （i.e., lower Mississippi alluvial plain）. Water bodies were categorized according to land use and implementation of agricultural best management practices （BMPs）. Sediment samples were collected at three sites within each water body from June to July 2004 and analyzed for 17 current and historic-use pesticides and metabolites. Twenty-eight day H. azteca survival and growth were measured to assess the degree of biological impairment. No significant （P 〉 0.05） mortality occurred in animals exposed to sediments. Significant growth impairment was observed in sediments from all three 303（d） listed water bodies and two of three BMP oxbow lakes. Historic-use pesticides and metabolites were implicated in two of five biologically impaired water bodies. Complex contaminant mixtures often limit attempts to provide clear, definitive sources of biological impairment. In this study, even accounting for sediment characteristics such as sand-silt-clay fractions and organic carbon content did not further clarify sources of toxicity in some water bodies. Finally, results show that implementation of BMPs can mitigate biological impairment within lake sediments.

关于吸收光谱的演示

一、引言吸收光谱的演示实验不仅是在一般中学物理教学中不易做成功,即使在高等学校的光学课上也很少去做.这样,学生在学习吸收光谱这个重要光学现象时,只能凭教师的口述或从挂图上去认识和想象,而不能看到生动的具体现象.为了加强吸收光谱这部分教学的直观性,我们对钠的线吸收光谱、太阳吸收光谱和带吸收光谱的演示反复地作了试验,并取得了一定的结果.

DVD-9粘接层厚度的在线控制

1 引言粘接工艺是DVD复制生产的核心工艺。对于DVD-5,一个单片的信息面在溅镀后与另一空白DVD单片粘接。对于DVD-9,DVD-10和DVD-18两个单片上的都具有溅镀后的信息面,要求更严格的粘接工艺控制。DVD-9的粘接层厚度及其局部变化、全盘变化对最终盘片质量影响非常大,需要精确的测试并严格控制。本文将介绍DVD粘接工艺的测试原理及DVD-9粘接层的离线和在线控制。

Carbon dots embedded in lead-free luminescent metal halide crystals toward single-component white emitters

The development of single-component white emitters for white light-emitting diodes(WLEDs)remains challenging.Herein,a rare earth-free white light-emitting composite is developed by assembling blue-emitting carbon dots(CDs)and yellow-emitting Cs_(2)InCl_(5)·H_(2)O:Sb^(3+)metal halide crystals via a facile liquid-liquid diffusion-assisted crystallization approach.The encapsulation mechanism is then analyzed.Depending on the ratios of blue/yellow emitters,these luminescent composites exhibit white light emission with tunable cold and warm hues.The composites also possess prominent ultraviolet resistance,thermal tolerance,and good stability at about 200°C.By employing such“CDs in metal halide”composites as a converter,a WLED is successfully fabricated with a high color rendering index of 93.6,benefiting from the assembled blue and yellow broadband emission.With this strategy,the developed composites show great promise in next-generation WLED lighting.

Transcriptional and translational responses of rapeseed leaves to red and blue lights at the rosette stage

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.