双通道PWM的冷暖白光LED混色模型研究

LED光色度的动态调节是实现智能照明的基础, 采用冷暖白光LED和双通道脉冲宽度调制(PWM)法,基于1931CIE标准建立混合光源模型,推导出混合光源色坐标、相关色温 、最大亮度、显色指数与双通道调制脉冲 占空比比值的关系式。采用暖白光(色温3282 K)和冷白光(色温12930K)两种白光LED进行 混色实验, 通过微控制器输出PWM信号控制LED驱动电源,改变冷色光和暖色光的比重,得到的混合 光源色坐 标、最大亮度、相关色温及显色指数值与理论计算值吻合很好,证明了理论模型的正确性。 理论和实验结 果还表明,混合光源在双通道调制脉冲占空比比值为1的附近可得到低色温、高显色性和大 光通量的混合白光。     

A novel fluorescent sensor for Al~(3+) and Zn~(2+) based on a new europium complex with a 1,10-phenanthroline ligand

A new europium complex Eu(tta)₃Li(la)based on 1,10-phenanthroline derivative(Li=(2-(3,5-dimethoxyphenyl)-1 H-imidazo[4,5-f][1,10]phenanthroline),tta=2-thenoyItrifluoroacetone)was designed and synthesized.Its structure was characterized by¹H and¹³C NMR,elemental analysis,UV-vis,fluorescence spectra and single crystal X-ray diffraction.The crystal of the complex la belongs to monoclinic system with the space group P2_1/n.The europium complex la in the solid and in the solution displays the typical emission of Eu(III)ion centered at 612 nm as a result of the electric dipole transition(⁵D₀-?⁷F₂).It exhibits high quantum yield(20.42%),long lifetime(0.29 ms)and good CIE color coordinate(0.67,0.33)in solid.In addition,the complex shows high sensitivity and selectivity towards Al³⁺and Zn²⁺in methanol solution which can be attributed to the Al³⁺/Zn²⁺cation instead of Eu³⁺in the complex la.The LODs for Al³⁺and Zn²⁺were calculated to be 5.880×10^-7and 7.678×10^-8mol/L,respectively.Besides,the additions of Al³⁺and Zn²⁺express remarkable color changes from red to bright blue and ivory that can be clearly observed by the naked eye respectively.     

化纤综合废水处理絮凝剂的筛选与应用

分别采用聚合氯化铝和聚合硫酸铝铁对化纤综合废水进行了絮凝反应对比实验,并对优选的聚合氯化铝的应用条件进行了研究。其最佳絮凝反应条件为:控制酸析反应的pH在2.20左右,絮凝反应前调节原水pH至5,絮凝剂最佳投加量为3‰,助凝剂选用阳离子型PAM,最佳投加量为3 ppm。絮凝反应使废水色度和COD分别下降67%和38%。     

染料型喷墨打印墨水色素的色度学分析

通过对四个打印机彩色三原色墨水的光谱透射率测定及色度学分析，得到每一颜色的三刺激值，色度坐标，比较了这4组三原色拼色的色域大小，彩度值，色相的主波长及补色波长。提出了三原色补色波长之间关系的一个经验公式：λcompl.M≌10/9（λcompl.Y） 10，及λcompl.M≌9/10（λcompl.C）-20，发现这4组三原色的补色波长与此公式有较好的适应性。     

Mixing and Simplex Search for Optimal Illumination in Machine Vision

Mixed-color illumination affects the quality of images in industrial vision system and it is important to optimize color and intensity for image acquisition. This study used simplex search to find the optimal illumination in a short amount of time. A typical color mixer synthesized various color of lights by changing the inputs of RGB power LEDs and passing the lights through an optical system. The image quality under mixed-color illumination was calculated according to the sharpness. For the purpose of optimal illumination using simplex search, a probe network was organized with N + 1probing points for N inputs. The shape of the probe network, simplex, was varied through procedures of extension, contraction, and shrinkage. The inputs of the color mixer were changed until the size of the simplex became smaller than a threshold. The simplex search was tested for commercial semiconductor patterns, and was useful for finding the optimal illumination.     

不同的漂剂对红麻磺化化学机械浆色度的影响

应用一种新颖的方法，研究了不同的漂剂对红麻磺化化机浆（ＳＣＭＰ）的颜色或色调的影响。结果表明，就去除纸浆的黄色调而言，ＮａＢＨ＿４和Ｈ＿２Ｏ＿２漂白是非常有效的，而效果以ＮａＢＨ＿４为最佳。ＣＨ＿３ＣＯＯＯＨ漂白浆的黄色调较深，而Ｈ＿２Ｏ＿２两段漂能获得比Ｈ＿２Ｏ＿２单段漂较浅黄色调的纸浆。     

色度图在舞台影视灯光设计中的应用

本文简要地介绍了色度图在舞台影视照明中的应用。     

A study on the chromaticity shifts of blue phosphor for color plasma displays

The dependency of the chromaticity shifts on the concentration of Eu²⁺ doped in BaMgAl₁₀O₁₇ (BAM) was investigated under heat‐treatment and vacuum ultraviolet (VUV) irradiation. The Eu²⁺ ions in BAM show an asymmetrical broad emission band with a maximum at ～452 nm under excitation of VUV light at room temperature, showing that multiple crystalline cationic sites exist in the host. It was found that the chromaticity shifts greatly decrease with increasing heat‐treatment temperature. Regardless of the Eu²⁺ concentration, the chromaticity shifts caused by heat‐treatment are greater than that caused by VUV irradiation. Compared with conventional BAM, a solid solution of BAM with barium aluminate as a powder and film was also studied, and very few chromacity shifts were observed. It is suggested that the distribution of Eu²⁺ ions in different sites in a BAM lattice results in different chromaticity coordinates. By increasing the Eu²⁺ concentration in BAM, or under heat‐treatment and VUV irradiation, the emission band shifts towards longer wavelengths.     

电化学法处理染料废水的研究

染料废水的处理是近年来各国环境领域的一个热点和难点。笔者采用电化学法处理染料废水,探讨了不同电极、不同电极间距和不同电解槽对染料降解效果的影响。结果表明,网状电极和带孔电极比板状电极的效果更为显著,其中8目铁网的效果最佳;缩短电极间距,可加快电解反应速度,同时降低温升,减少能耗;圆筒形电极电解槽比传统矩形电解槽反应效果好。电化学法对染料废水的COD和色度的去除非常有效,是一种非常有实用前途的处理方法。