不同涂装体系的耐候性试验研究

通过不同涂装体系的耐候性对比试验,探讨了不同涂装体系在自然曝晒条件下耐候性的差异,从而总结出两涂层和三涂层的差异,并提出了简化涂装体系的可能性。     

Mineral weathering in forest soils and its relevance to the preservation of the buried archaeological resource

There is more woodland in Britain now than for many centuries and considering many international climate change mitigation policies, woodland cover, both in Britain and internationally, is being promoted. However, neither the management of existing woodlands nor their expansion should be at the expense of important archaeological evidence. Due to the large number of known archaeological sites, the large areas of land with uninvestigated archaeological potential and the expanding woodland cover, suitable mitigation strategies need to be developed to allow preservation in situ of important sites. An understanding of how woodland soils and the buried archaeological resource interact is, therefore, essential. This paper utilises ongoing environmental research into the mineral weathering rates in forest soils and considers its application to artefact preservation. The study concludes that soil water pH, its movement, and the saturation of dissolved ions in the soil solution are major factors determining both mineral and artefact longevity. A simple guide to artefact longevity based on these properties is proposed and a geochemical model for predicting loss is tested. These tools could be applied to any soil or individual horizon irrespective of land-use.     

Sample temperatures during outdoor and laboratory weathering exposures

Effective exposure temperatures (T_eff) in Arizona were calculated from hourly or 10-min parsed irradiation data along with ambient, black panel, and sample temperatures. The T_eff represents a constant temperature that creates the same amount of photodegradation as the naturally varying temperature and provides a benchmark temperature for making lifetime predictions from accelerated laboratory exposures. The annual ambient and black panel T_eff at a Wittmann, Arizona site were 30 °C and 42 °C, respectively, assuming that the photodegradation has an activation energy (E_a) of 21 kJ/mol (5 kcal/mol). T_eff was only weakly dependent on E_a over the range of 10-40 kJ/mol (3-10 kcal/mol). Samples exposed as van sunroofs were found to have T_eff that were offset from the black panel temperatures by a constant amount for the entire year. Thus, measurements of sample and black panel need to be made for only a few weeks to determine the offset and give the annual sample T_eff if the annual black panel T_eff is known. Light-colored samples probably are better compared with the ambient temperatures. Sample temperatures in xenon arc exposures usually are higher than the outdoor T_eff, so Arrhenius temperature corrections need to be carried out to relate accelerated to outdoor exposures. Temperatures in xenon arc exposure tests often correspond more closely to maximum temperatures that samples might encounter for only a few hours per year.     

河北某矿区蚀变围岩力学特性

河北某矿区围岩为蚀变岩 ,遇风、水强度显著降低且有风化水解现象 ,严重影响了生产和安全 .本研究针对矿区的主要蚀变围岩进行了力学指标测试 ,并用模拟现场环境的方法试验研究了风化对岩石物理力学性质的影响 ,试验结果为矿山安全生产提供了参考     

光伏电缆耐候性试验箱的设计

设计了用于光伏电缆耐候性试验的人工气候加速老化试验箱,介绍了其结构组成及工作原理.采用PLC与HMI相结合的方式对系统进行监测控制,并提出了一种旋转式试样架结构对其进行优化.该试验箱能够产生多种用于加速老化试验的人工气候环境,具有结构简单、安全可靠、自动化程度高等特点;其显著的兼容性和通用性,可广泛用于线缆以及类似材料的人工气候加速老化试验,同时也为其他类似技术问题提供参考.     

几内亚某矿区铝土矿成因及找矿标志

矿区位于几内亚共和国西部,非洲大陆西北部的西非克拉通内。主要由前寒武纪基底和古生代-新生代盖层构成,太古界变质岩系及其中分布的混合花岗岩和绿岩带是大型金属矿床的主要矿源层。勘查区南矿段濒临大西洋,西南距大西洋海岸约40 km ,属于“下几内亚”沿海平原丘陵区;北矿段位于下几内亚和中几内亚的结合部,属于中低山区,东部与中几内亚富塔贾隆高原接壤。该铝土矿矿床为风化残余型,开采技术条件简单,矿石自然类型为三水铝石型,工业类型为高铁低硫型,是目前世界上在拜耳法条件下提取氧化铝最易加工处理的矿石类型。目前该矿区共获得（332）＋（333）铝土矿资源量20亿 t ,属超巨大型矿床。     

耐火耐侯钢热装温度对高温性能与组织的影响

对耐火耐侯钢的高温性能进行热模拟研究,发现该钢在500℃装炉时钢的高温强度最低,比冷装炉钢的高温强度低20MPa,600℃装炉时钢的高温强度最高,比冷装炉钢的高温强度高40MPa。总体来说,热装不会影响该钢的高温性能,热装温度高于600℃对该钢的高温性能更为有利。600℃以下装炉,该钢加热奥氏体晶粒度与冷装的差不多。600℃以上装炉,加热奥氏体晶粒度比冷装炉的要小l级左右。     

CSP转炉冶炼高强耐候钢板坯质量分析

采用原位统计分析方法,计算得到CSP线使用转炉冶炼高强耐候钢铸坯各组成元素的偏析度．定量检测出了铸坏的偏析部位及其变化;从钢坯横剖面不同部位致密度的三维立体图和二维等高图,直观地表述铸坯的缩孔、疏松的部位及其变化,得到剖面上任意指定位置的致密度数值。经转炉冶炼、LF精炼和连铸工艺生产的高强耐候钢板坯质量优异。     

经济耐候钢的研究

系统研究了Mn、Cu含量及腐蚀环境体系对协同作用的影响,并利用电化学测试、扫描电镜、XRD等材料分析技术对带锈电极的腐蚀行为、锈层组成、结构和性质进行了深入分析,阐述了Mn-Cu合金化协同作用的机制;利用Mn-Cu合金化的协同作用,成功开发出Mn-Cu型经济耐候钢和实现工业化试生产。实验表明：热轧Mn-Cu钢具有良好的耐候性,其耐候性略优于传统的09CuPTiRE和SPA-H耐候钢。     

古老变粒岩区岩体风化规律的研究

古老变粒岩地区 ,岩体风化剧烈、风化深度大且各处风化深度差异极大 ,地表多呈散砂粒状 ,该文对其在水利水电工程地质勘察中遇到问题进行了深入研究 ,初步掌握了古老变粒岩区岩体风化规律