光致变色玻璃的性质与应用

本文将论述光致变色玻璃(Photoohromic glasses)的成分和特征,即那些在日光或其它合适的光线照射下变暗,而光照解除后又重新复明的玻璃成分。 卤化银的光化机理将用以作为解释这些玻璃光致变色现象的借鉴。文章中介绍了若干实用的性能,其中特别注意商品牌号为Bestlite~(TM)的玻璃在眼镜方面的应用。另外的一些可能的用途也将提及。一些演证和一部短的彩色影片将用来解释这种光致变色反应。     

全色光敏玻璃

我们早已对胶态金属的色彩予以青睐。过去对胶态金、银和铜着色的光敏硅酸盐玻璃以及采用一种或多种此类金属核化的白色或着色的乳浊光敏玻璃和含有胶态卤化银的光致变色玻璃已有过介绍。在研究某些含银的氟化钠乳白色光敏玻璃时,当在产生光·乳浊效应     

卤化铜光致变色玻璃变色机理研究

本文报道了卤化铜光致变色玻璃中光色相物相分析方法和玻璃中铜胶体理论吸收光谱的计算方法。测定了玻璃的顺磁共振谱(ESR)和可见吸收光谱。证明了卤化铜光致变色玻璃的变色机理是CuX自身氧化还原的胶体暗化过程。     

卤化银光色玻璃的光致变色动力学模型

以卤化银光色玻璃在发生光色过程中Ｘ＾－的电子逸出几率α和Ａｇ＾＋的电子俘获几率ｐ为基础,推导了卤化银光色玻璃的光致变色动力学模型。比较了Ｆ系列卤化银光色玻璃的理论的变色动力学曲线与实测的变色动力学曲线,并讨论了光致变色的速度与辐照时间的关系,最后探讨了饱和变暗透过率与５ｍｉｎ变暗透过率的差异。     

光致变色玻璃在建筑中的节能性能评估

光致变色玻璃的透光率随光辐射强度的不同而变化,因此,光致变色玻璃可用于调控阳光进入建筑,是具有节能功效的智能玻璃。然而,目前光致变色玻璃在建筑中应用的研究较少,缺少科学评价其节能性能的方法。本文以制备的卤化银光致变色玻璃为研究对象,建立了光致变色玻璃节能性能简化模拟方法。利用DeST能耗软件研究了光致变色玻璃应用于不同建筑中的节能效果,计算和比较了两种变色特性的光致变色玻璃在不同建筑中的冷热负荷和照明能耗。研究结果显示:光致变色玻璃在建筑面积较大且窗墙比0.6以上的公共建筑中,全年节能率最高超过10%;在建筑面积和窗墙比较小的建筑中,其主要作用在于阻隔紫外线和防眩光。本文的方法和结果可为光致变色玻璃节能性能的研究提供参考,对光致变色玻璃的应用推广具有一定的促进作用。     

叠层共烧微波介质陶瓷器件的银扩散机理

采用玻璃和氧化物助烧剂在900℃烧结制备了4种不同介电常数的微波介质陶瓷。研究了叠层共烧工艺制备的微波介质陶瓷器件的银扩散机制。结果表明：银扩散现象不仅与陶瓷基料有关,还与引入的助烧剂种类及用量有关。玻璃助烧剂易产生扩散渗银现象,减少玻璃助烧剂用量有利于减轻扩散渗银。在选用的4种陶瓷中,ZnTiO3和7Li2O-4Nb2O5-6TiO2(摩尔比)陶瓷扩散渗银现象不明显,采用ZnTiO3陶瓷制备的滤波器件性能稳定。     

光致变色的玻璃涂层

这种光致变色的涂层材料,采用具有光致变色作用的钛酸锶或钙的粉末与铅玻璃熔块、起混和而成。 在另一种玻璃表面,涂上该种光致变色的釉料     

铜在卤化银光色玻璃中的作用

一、前言 迄今为止,几乎所有的光色玻璃都含有少量铜,因为铜能显著增加玻璃的变暗灵敏度。 Moser等曾研究过铜在卤化银单晶中的作用,他们认为渗杂Cu的卤化银晶体感光性能增强,是由于Cu~+在AgCl等单体内起着空穴捕获中心的作用,增加了感光后Ag°的生成量:     

玻璃中卤化银纳米棒定向排布制备

围绕含AgCl钠硼硅酸盐玻璃的熔融制备、析晶热处理、高温拉伸及高压还原工艺，对于玻璃中卤化银纳米棒的形成、定向排布以及对于偏光性能的影响规律进行了研究，发现卤化银晶粒更易于在富钠硼相中析出，较佳的热处理制度是析晶温度615℃、保温时间12 h。玻璃中卤化银纳米棒的形成及定向是玻璃拉伸温度、拉伸应力与拉伸速度三者的有机结合。在拉伸温度570℃、拉力735 N、拉伸速度120 mm/min条件下，玻璃样品中Ag Cl纳米棒的平均直径98 nm、平均长度558 nm、纳米棒的平均长径比1.0:5.6，并沿玻璃拉伸方向定向排布。通过高压还原后玻璃的偏光性能研究，拉伸后玻璃表层单位面积内AgCl纳米棒的数量越多，还原处理后玻璃的消光比越高。     

明胶大分子对卤化银乳剂照相过程的影响

<正> 自从1871年Maddox将卤化银晶体分散于明胶制作照相材料以来,到现在一百多年,明胶仍然是卤化银的分散介质和粘合剂的主要原料。明胶具有许多适合于制作照相材料的物理的和化学的性质;这些性质是其它天然的和合成的聚合物所没有的。目前只能用合成聚合物取代部分明胶,以改善照相材料的物理机械性能。明胶聚肽大分子由18种氨基酸组成。认为影响卤化银乳剂照相过程的主要是其中一些含氧、氮、硫的氨基酸残基,如表1所示。 1.明胶在卤化银晶体表面的吸附明胶大分子主要是通过它在卤化银晶体表面的不可逆吸附来影响照相过程的。通常,聚合物分子以其在溶液中的无规线团构象吸附于固体表面,并且大分子只将     

宽热处理制度AgX光色玻璃的研制

本文研制了一种K2O-B2O3-Al2O3-SiO2系统AgX光色玻璃。此玻璃具有较宽的热处理制度,在610～670℃和2～8h之间进行热处理,热处理温度和时间对玻璃的光色性质影响不大。所以,可作为大面积无色差的平板光色玻璃材料来进一步研究。     

Coloration and Photochromic Properties of Glasses in the BaO–PbO–Al2O3–B2O3 System

A systematic spectrophotometric study of the compositions of photochromic glasses in the BaO–PbO–Al₂O₃–B₂O₃ system is performed for different combinations of photochromic additives. It is revealed that the chosen composition of the base glass facilitates the formation of colloidal silver particles, even though silver is involved in any combination of photochromic additives. This is especially true for a low content of halogen ions [1 wt % (Cl^– + Br^–)] at the concentration ratio [Ag]/[Hal] = 0.33. As a result, the glass changes to a reddish brown color and does not exhibit photochromic properties. An increase in the halogen concentration in the range [Ag]/[Hal] = 0.07–0.33 results in a decrease in the amount of colloidal silver particles. Most likely, this is accompanied by an increase in the content of the silver halide phase; that is, the necessary content of the photosensitive phase is provided to manifest the photochromic effect in the studied glass.     

An Alternative Model for Photochromism of Glasses: Reversible Injection of Carriers from a Microcrystal and Its Surface States into Point Defects of Glass

The radiation-induced absorption spectra of photochromic homogeneous silicate glasses and heterogeneous borosilicate glasses containing AgCl, AgBr, or CuCl microcrystals are analyzed. The inference is made that these spectra contain the bands of traditional radiation-induced color centers (RICCs) in glasses and the bands of halide defects in microcrystals. The band model of the photochromic process in the microcrystal–surface states–glass system is proposed on the basis of the performed analysis with due regard for burning of the exciton hole in the induced spectrum of CuCl-containing glass. This model makes it possible to explain a large number of experimental data.     

Preparation and photochromic behavior of borosilicate aluminate glass for smart window and curtain wall applications

Sunlight-induced photochromic glass exhibits attractive application prospects in the field of architecture materials. In this work, a series of borosilicate aluminate photochromic glasses containing AgCl nanocrystals were prepared. The photochromic property and mechanisms were systematically investigated. The color of the glass turned from transparent to black (or dark grey) under the irradiation of 365 nm ultraviolet light (or sunlight). Placing in a dark environment, the color of photochromic glass gradually restores to its initial state. From the results of in situ TEM and XPS measurement, it is found that the photochromic and self-bleaching behavior of borosilicate aluminate glass originated from the formation and decomposition of silver nanoparticles. Utilizing the photochromic and self-bleaching properties of the glass, the transmittance of the glass could be reversibly modulated. The cycle measurement shows excellent repeatability, demonstrating the potential application of AgCl-contained borosilicate aluminate photochromic glass in the fields of smart building windows and curtain walls.     

Optical Absorption of Silver in Photochromic Glasses: Optically Induced Dichroism

The absorption spectrum of silver halide-based photochromic glasses darkened by uv light is shown to vary with glass composition and photochromic heat treatment. The nature of the absorption is explained in terms of the anisotropic geometry of the photolytically produced silver specks. A correlation is established between the uv-induced spectrum and the dichroic behavior that can be induced by bleaching with polarized light. A specific model is proposed for the silver-speck geometry and calculations show goad agreement with experimental data.     

溶胶凝法制备铜镉光色玻璃涂层的研究

用溶胶凝胶法在普通平板玻璃表面上制备了铜镉光色玻璃涂层。样品具有可逆的光色性。X-射线衍射和红外光谱分析表明：铜镉光色玻璃涤层的光色相为CuBrxCl1-x固溶体,结构网络由Si-O-Si、Si-O-B和Si-O-Al健连接而成。