可逆感温变色聚丙烯专用料的制备及性能

通过两步法制备可逆感温变色聚丙烯（PP）专用料，首先将乙烯-辛烯共聚物（POE）与可逆感温变色粉于微型双螺杆挤出机中挤出造粒制备色母料，然后将PP与色母料熔融共混挤出制备可逆感温变色PP专用料。探讨了色母料含量对PP专用料感温变色性能、力学性能、热学性能及微观形貌的影响。结果表明，利用POE与PP良好的相容性，实现了可逆感温变色粉在PP基体中均匀的分散，可逆感温变色PP专用料表现出优异的可逆感温变色性能和冲击性能。     

A Water‐Soluble Mechanochromic Luminescent Pyrene Derivative Exhibiting Recovery of the Initial Photoluminescence Color in a High‐Humidity Environment

Switching of the luminescence properties of molecular materials in response to mechanical stimulation is of fundamental interest and also has a range of potential applications. Herein, a water‐soluble mechanochromic luminescent pyrene derivative having two hydrophilic dendrons is reported. This pyrene derivative is the first example of a mechanochromic luminescent organic compound that responds to relative humidity. Mechanical stimulation (grinding) of this pyrene derivative in the solid state results in a change of the photoluminescence from yellow to green. Subsequent exposure to water vapor induces recovery of the initial yellow photoluminescence. The color change is reversible through at least ten cycles. It is also demonstrated that this compound can be applied as a mechano‐sensing material in frictional wear testing for grease, owing to its immiscibility in non‐polar solvents and its non‐crystalline behavior. Transmission electron microscope and atomic force microscope observations of samples prepared from dilute aqueous solutions of the pyrene derivative on suitable substrates, together with dynamic light scattering measurements for the compound in aqueous solution, indicate that this amphiphilic dumbbell‐shaped molecule forms micelles in water.     

Experimental study of free convection in a window with a heated between-panes blind

An experimental study has been conducted to examine free convection in a window with an enclosed aluminum venetian-type blind. The unique feature of this experiment was that the blind slats were heated electrically to simulate absorbed solar radiation. Convective heat transfer measurements and temperature field visualization were obtained using a Mach-Zehnder laser interferometer. Optical measurements were made for two glazing spacings, two blind slat angles, two blind heat flux levels, and two glazing temperature differences. Both local and average convective heat flux data were obtained in the center region of the tall air-filled enclosure. At the widest glazing spacing, the temperature field was found to be unsteady. For these cases, the temporal fluctuation of the local convective heat transfer was time-averaged using a high speed camera. The experimental results have been compared to a simplified method in the literature for predicting the center-glass heat flux for this configuration.     

热致变色功能薄膜的制备及应用研究进展

热致变色功能薄膜作为一类很有潜力的功能材料,在生产、生活等许多领域发挥着非常重要的作用.本论文系统介绍了真空蒸镀法、反应溅射法、化学气相沉积法、溶胶-凝胶法、组合遥控体系"M-ist Combi"法、L-B膜法以及分子自组装法等热致变色功能薄膜的制备方法,综述了其最新应用进展,并对其发展趋势进行了展望.     

无机盐离子对多孔VO_2薄膜微观形貌及热致相变性能的影响

以云母(001)为衬底,采用无机溶胶-凝胶法,通过添加表面活性剂十二烷三甲基溴化铵(CTAB),以及加入同一元素族、不同粒径的无机盐离子Li+、Na+、K+和同一周期、不同价态的Na+、Mg2+、Al3+制备多孔VO2薄膜。采用SEM、FT-IR等手段分析薄膜的微观形貌特征和热致相变性能。结果表明,不同化合价、不同粒径的无机盐离子对多孔VO2薄膜的颗粒尺寸分布、微观形貌以及热致相变性能产生影响。     

变色织物生产技术

综合叙述变色织物的三种生产技术,即纤椎技术、染色技术和印花技术。     

Efficient calculation of daylight coefficients for rooms with dissimilar complex fenestration systems

The daylight coefficient (DC) method is a powerful and efficient method to perform annual daylight illuminance simulation. A set of coefficients are calculated for a given room space and static fenestration systems prior to simulation start. Time series of indoor daylight illuminances are obtained by only knowing the sky luminance. However, for rooms with dissimilar dynamic complex fenestration systems (such as windows with movable shadings) whose optical behaviour (transmission, reflection and scattering) may change during simulation, the efficiency of the DC method may be compromised as another whole set of coefficients must be re-calculated. This study presents the development of a new methodology to compute the DC set for rooms with dissimilar complex fenestration components only once prior to simulation start. A validation study is carried out, in which the daylight illuminances in an office space equipped with a clear window and internal Venetian blinds are compared using predictions from the present model, the Radiance program, as a benchmark model employing detailed optical model of Venetian blinds, and the Daysim program employing a simple engineering blinds model. Findings from the validation study show that the present model yields overall accurate results when compared with the benchmark model for any window orientation, although some local illuminance differences are observed in areas under direct sunlight exposure.     

结晶紫-硼酸体系的热变色性能研究

选用羧酸类溶剂,采用固相法合成了结晶紫-硼酸系列可逆热致变色材料。考察了结晶紫和硼酸的配比、羧酸类溶剂的种类与用量以及环境温度对其热变色性能的影响。结果表明:以草酸为溶剂时,m(结晶紫)∶m(硼酸)∶m(草酸)=1∶350∶100时,颜料变色敏锐,变色温度降低到58℃,复色时间为16s,可逆性好;以丙二酸为溶剂时,m(结晶紫)∶m(硼酸)∶m(丙二酸)=1∶350∶1000时,颜料加热到68℃时,开始由浅绿色逐渐变为浅黄色,颜料色彩鲜艳,变色敏锐,复色时间仅为8s,可逆性好。DSC检测颜料的热变色过程发现2个样品在55～75℃之间都有很大的吸热峰。     

变色材料的研究进展

介绍光致变色材料、热致变色材料和电致变色材料的变色原理、研究现状、制约发展的条件及其它们在军事伪装、汽车、建筑、纺织服装和日用品等领域的应用。重点探讨电致变色材料(导电高分子、无机与有机制成的复合薄膜、其他类高分子电致变色材料等)。在此基础上,对变色材料的发展趋势进行展望,并指出电致变色材料是未来发展的趋势。