三种涂层在模拟热带海洋大气环境中的性能退化研究

为了考核评价舰船、舰载机等装备用三种涂层在热带海洋大气环境中的性能退化情况，设计了涂层在实验室模拟热带海洋大气环境中太阳辐射试验、湿热试验和盐雾试验的组合循环试验方法。通过实验室组合循环试验，分别检测了试验前后涂层的形貌、失光率、色差、附着力和电化学阻抗等数据。试验结果表明，随着试验时间的延长，三种涂层均出现不同程度的老化，失光率和色差呈增大趋势，附着力降低；但试验前后其老化机理未发生明显变化，电化学交流阻抗值基本保持在109Ω以上，涂层的厚度基本保持不变。综合三种涂层的性能退化对比，在工程实际应用中推荐优先选用4号或10号涂层。     

有机涂层户外失效分析及对策

我国气候类型复杂,有机涂层在一些典型气候条件下经过一段时间的户外暴露后都会出现粉化、颜色变化、剥落、沾污等明显变化.综合起来分析,当地太阳辐射强度、辐射量、温湿度等是有机涂层失效的主要因素;同时空气中的污染物、沙尘等也加速了有机涂层失效.因此研制新型户外涂料时要确保有机涂层既能起防护作用,又能起装饰作用,以增强有机涂层...     

几种涂层氙弧灯光老化试验加速性研究

太阳辐射是引起有机材料老化的最主要原因,实验室氙弧灯光老化试验具有较高的加速性。本文通过对有机涂层在广州试验站自然暴露试验结果以及实验室氙弧灯光老化试验结果进行对比研究,得到3种常用有机防护涂层的加速倍数,对于1#、2#样品的加速倍数为9,3#样品的加速倍数为6。     

太阳辐射对户外密闭箱体热影响的试验研究

本文对不同颜色户外密闭箱体受太阳辐射的热影响进行了试验研究。通过对深绿、沙漠黄和白色三种颜色的密闭箱体进行的太阳辐射热影响试验，得出不同颜色对太阳辐射热量吸收的差异，并通过箱体温度、箱内空气温度等变化，得出户外密闭箱体/箱内温度一天内的变化以及一年内的变化，对箱内环境温度受太阳辐射影响引起的温升进行了摸底，以及箱体温度和箱内温度进行了摸底，对户外密闭箱体的热设计具有重要的参考意义。     

应用于高盐高辐照环境下的钢结构涂层防护行为研究

为研究在严酷环境下涂层对钢结构的防护性能，本文通过对应用于钢结构外表面、内表面以及钢支架的涂层进行了1年的现场暴露试验以及2000h的模拟加速腐蚀试验，积累了涂层在钢结构的老化数据，获取了涂层的腐蚀等级评级。结果表明：现场暴露1年后，载荷尚未产生明显的影响，所有涂层均未出现失光、变色、粉化、开裂、起泡等老化现象；经过2000h盐雾试验后，涂层表面形貌未发生明显变化，涂层未出现起泡、开裂和出锈等现象，表明涂层具有良好抗盐雾和水汽的渗透能力；经过2000h紫外老化试验后，涂层均未出现严重的老化现象，但都出现了不同程度的变色和粉化现象。     

山西省近50年气候变化特征分析

根据近50年来山西省18个气象基准站1960—2004年间的逐月气温、降水量和山西气象观测台(太原站)1966—2005年的逐月太阳辐射资料的统计,对山西省的气候变化进行了较系统的分析。结果表明,近50年来山西省气温上升趋势明显,而且在1990年有一次明显的跃变(1990年的累积距平等于零),年平均温度以0.25℃/10a的幅度上升;降水的年变化呈下降趋势,平均以18.7mm/10a的幅度下降,在1990年也有一次跃变;年总太阳辐射量亦呈下降趋势,且在1982年有一次明显的突变,年平均太阳辐射总量以每10年238.9204 MJ/m2的幅度下降。1982年以前以正距平为主,1982年后以负距平为主,且跃变的幅度较明显。     

汽车模拟日照太阳辐射试验设备研制

本文根据汽车整车太阳辐射试验的要求，介绍了自主设计的基于红外线灯泡阵列的无紫外线汽车模拟太阳辐射试验设备的总体方案，并重点讨论了在光源、电气控制等各方面的设计思路及具体实现过程。     

铝合金表面用导电屏蔽涂层耐介质腐蚀行为研究

通过研究不同尺寸及分布的银粉对涂层表面电阻的影响，确定了导电屏蔽涂料最佳配方，制备了一种高导电、耐腐蚀涂层。采用SEM、EDS、四探针电阻测试仪等分析涂层在空气、水、盐水、中性盐雾、酸性盐雾中表面形貌及性能变化，从而揭示涂层腐蚀行为。结果表明：经历500 h试验后，涂层在空气中几乎没有发生变化，但是在含水等电解质的环境中腐蚀迅速，并且腐蚀速率具有纯水<水汽<盐水<中性盐雾<酸性盐雾的特征。腐蚀的主要原因是由于基材Al与涂层形成了电偶腐蚀，腐蚀初期表现为起泡，随着腐蚀的加剧，涂层表面布满白色、黄色、褐色的疏松腐蚀产物且漆膜出现脱落，当腐蚀进一步加剧扩大，疏松产物转变为较为致密的产物附着于涂层表面，此外，涂层导电性能会随着腐蚀程度的变化出现不同等级的下降。     

移动式太阳辐射热效应系统的设计与应用

GJB 150.7A-2009 《军用装备实验室环境试验方法第7部分:太阳辐射试验》规定了军用装备实验室太阳辐射试验的试验要求和试验过程。针对于此标准的要求,本文设计出一款易拆装、可灵活移动的新型移动式太阳辐射热效应试验系统。该系统由步入式高低温实验室、光照度监控系统和整车红外加热系统组成。不仅能满足GJB 150.7A-2009 《军用装备实验室环境试验方法第7部分:太阳辐射试验》第4.3.3.1条款"程序Ⅰ"的试验要求还兼顾汽车主机厂的企业标准,如东风汽车等。     

紧固件表面无铬锌铝涂层的腐蚀行为研究

紧固件实际安装使用时，表面涂层会受到一定的力矩使其发生破坏，为了探究螺栓在实际安装使用情况下的腐蚀行为，本论文选用具有无铬锌铝涂层的螺栓为研究对象，通过扭矩扳手在螺栓上加载60 N·m的力对表面涂层进行破坏，以模拟涂层实际安装使用时的表面状态，并通过中性盐雾试验探究加载力矩后涂层的腐蚀行为。研究表明锌铝涂层具有很好的防护性，加载力矩的螺栓表面涂层被破坏后仍能表现出很好的耐蚀性，经过60d试验涂层表面破损处未观察到红锈，电化学测量结果表明加载力矩后的破损涂层仍然具有很好的屏蔽和阴极保护作用。     

电子设备太阳辐射试验系统的研制

对自行研制的电子设备太阳辐射试验系统进行了介绍。设备研制中对试验系统的辐照灯阵进行了优化设计，同时根据环境试验要求，介绍了太阳辐射试验设备研制过程中所遇到的辐射光源选择及强度控制、光谱分布修正和光源启动系统等技术难点，并给出了解决途径。该试验系统研制成功，为考核装备的环境适应性和产品可靠性提供了科学的试验手段。     

油漆涂层老化黄变分析

汽车涂装后形成的涂层,既要具备较好的外观装饰效果,又必须具有优良的防护性能,而在实际使用过程中,常因涂层老化而发生的黄变,严重影响了其原有的性能要求。文章分析了涂层老化黄变的原因,对比分析了几种面漆的耐老化性能,并提出提高涂层耐黄变性能的措施。     

Low VOC latex paints from a precipitation polymerization process

Even though paints and coatings have been very useful in protecting various substrates, their use has been accompanied by a heavy environmental price. There is a need to minimize the use of volatile organic compounds (VOCs) in the formulation of these materials. In the latex paint area, we have implemented a conventional precipitation process in emulsions to form binder particles that contain block copolymers and have softer blocks on the particle surface. The softer surface provides the binder film-forming properties without the need for the use of solvents or VOCs. The covalent connections between the soft blocks and the hard blocks are expected to impart good performance in the resulting dry coatings. Indeed, we have shown that our test coating from these binder particles containing block copolymer have similar properties in most performance categories to those of a semi-gloss control paint that has been formulated with typical amounts of VOCs.     

Photo-oxidation of NO using an exterior paint--screening of various commercial titania in powder pressed and paint films

The present work aims to evaluate the photocatalytic activity of photo-TiO(2) from various producers (Evonik, Kemira, Kronos, Millennium, Sachtleben and Tayca), in the form of powder pressed films and upon incorporation in a water-based paint, for outdoor NO abatement. The photocatalytic activity of the different samples was evaluated in terms of NO conversion and selectivity towards nitrite and nitrate ions following approximately the ISO 22197-1:2007(E) standard. The highest yields obtained for powder pressed films were achieved with VLP7000 (0.70), followed by VLP7101 (0.55) and UVLP7500 (0.55), all from Kronos. On the other hand, when incorporated in paint films, the highest yields were obtained with PC500 and PC105 from Millennium and UV100 from Sachtleben (ca. 0.15). The paint matrix plays an important role on the photocatalytic activity. In particular, the time for steady state is one or two orders of magnitude higher when the photocatalysts are incorporated in paint films in relation to the powder pressed films. The paint films were activated following the procedure recommended by the above-mentioned standard. However, the photocatalytic activity of films incorporating P25 (Evonik) was displayed only when higher power radiation and higher humidity conditions were used. This allowed for similar levels of photocatalytic activity as the other paint films.     

Comparison of the daily global solar radiation from different data sources in Northwest China climate

The solar radiation data are of high importance to the solar energy systems. Conventional methods to obtain the solar radiation data are from weather stations, solar radiation models, commercial software databases, and field measurements. In the present study, a new daily global solar radiation model is proposed, by combining the quadratic function of sunshine fraction and sine function of the day of the year. The solar radiation model calculated data are then compared with China Meteorological Data Sharing System (CMDSS) data, TRNSYS data, and field-measured data in Northwest China climate. It is found that the newly proposed solar radiation model has better performance than the other nine solar radiation models in the literature. The solar radiation model calculated data fit well with the CMDSS annually average data. The TRNSYS data are a bit larger than the CMDSS annually average data in summer half year and a little smaller than those in winter half year. The solar radiation model and the CMDSS annually average data have the best correlation, whereas the TRNSYS data and the field-measured data have the worst correlation. The solar radiation model calculated data have the best correlation with the other three data sources.     

A simple method for partitioning total solar radiation into diffuse/direct components in the United States

Solar radiation is a major sustainable and clean energy resource, and use of solar radiation is expected to increase. The utilization efficiency of solar energy varies with the relative proportions of the direct and diffuse components that compose total solar radiation and with the slope and aspect of the irradiated surface. The purpose of this paper is to develop a simple method for estimating diffuse and direct solar radiation at sites with observation of only total solar radiation. An existing model for estimating diffuse radiation, i.e., a linear relationship between the diffuse fraction (the ratio of diffuse radiation to total solar radiation) and the clearness index (the ratio of total solar radiation to extraterrestrial radiation), is applied to 7 sites across the continental United States with observations of diffuse and total radiation. The linear model shows good monthly performance. The model parameters (slope and interception) show a strong seasonal pattern that exhibits small variation across the 7 sites; therefore, the average values of the two monthly parameters may be used for estimating diffuse radiation for other locations with observations of total radiation.     

Energy and exergy analysis of a heat storage tank with a novel eutectic phase change material layer of a solar heater system

Solar energy is one of the most important renewable energy sources, but it is not available every time and every season. Thus, storing of solar energy is important. One of the popular methods of heat storage is use of phase change materials (PCMs) which have large thermal energy storage capacity. In this study, the heat storage tank in a domestic solar water heating system was chosen as control volume. The experiments were performed in the province of Elaz?g, Turkey, in November when solar radiation was weak due to cloudy sky. The heat storage tank of the system was modified to fill PCM between insulation and hot water part. A few PCMs which are Potassium Fluoride, Lithium Metaborate Dihydrate, Strontium Hydroxide Octahydrate, Barium Hydroxide Octahydrate, Aluminum Ammonium Sulfate, and Sodium Hydrogen Phosphate were analyzed to proper operating conditions using a Differential Scanning Calorimeter (DSC) and the best PCM was obtained with the Aluminum Ammonium Sulfate and Sodium Hydrogen Phosphate mixture. Thus, eutectic PCM was obtained and used in a heat storage tank of the solar water heating system. Energy and exergy analysis of heat storage tank was performed with and without the PCM. Energy and exergy analysis has shown that the heat storage tank with the PCM is more efficient than without the PCM and the maximum exergy efficiency was obtained as 22% with the heat storage tank with the PCM.     

Prediction of diffuse solar radiation using satellite data

In the project of the solar systems, the values of the solar radiation of a region must be known. The global solar radiation measurements are performed by the Turkish Meteorological Service in Turkey, while the diffuse solar radiation measurements are unavailable. In this study, some new models for predicting the monthly average daily diffuse solar radiation on a horizontal surface for Erzincan, Turkey are developed using satellite data. The evaluation of the models is carried out with the statistical analysis methods of mean bias error (MBE), root mean square error (RMSE) and correlation coefficient (r). The results are proved that the correlation equations obtained in here can be used to forecast diffuse solar radiation reasonably well.