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本文研究了光激励发光材料BaFCl:Eu中的发光中心。在不同的反应气氛下BaFCl:Eu具有不同的发光性质。利用光谱的方法、X射线光电子能谱的方法,研究了在不同条件下制备的BaFCl:Eu样品中,稀土离子Eu的性质。 相似文献
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目的 制备吡啶二甲酸铕的稀土配合物,将其加入胶版油墨中,并对荧光性能进行检测和分析。方法 以稀土材料Eu盐为主要原料,在一定条件下与2,6-吡啶二甲酸反应形成一种光致发光的稀土配合物,并通过红外光谱和荧光光谱对物质结构进行表征。将合成的稀土配合物添加到白色胶印油墨中,通过印刷适性仪将油墨打印在纸张上。结果 通过荧光检测确定了该物质的主要激发波长为365 nm,发射波长为617 nm;在紫外灯照射下,加入质量分数为3%~4%发光材料的油墨所打印图案的油墨颜色接近于稀土材料的荧光颜色;在D65光源下,该油墨的色度与之前相比变化不大,且可以在加网的条件下完成印刷。结论 稀土发光材料在胶印油墨中发光性稳定,且稀土材料荧光体在油墨中可发光,实现了稀土发光油墨对有机荧光油墨的替代,有利于环境的保护。 相似文献
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几种常用缓冲材料的性能研究 总被引:14,自引:11,他引:3
通过对泡沫塑料、蜂窝纸板、海绵等8种缓冲材料的冲击振动性能测试,得到各种材料的缓冲系数及其性能曲线,并综合以上数据进行比较分析,为各种材料在缓冲包装中的应用提供理论依据. 相似文献
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Jorge Marcondes Kayo Hatton Jennifer Graham Herb Schueneman 《Packaging Technology and Science》2003,16(2):69-76
Foamed plastics are used to cushion products to protect them from shock and vibration. Design data is in most cases derived from laboratory tests, performed under standard conditions. However, during distribution, most shock and vibration events occur under conditions different from those under which the materials were evaluated. Two commonly used foams in packaging, expanded polyethylene and expanded polystyrene, were used to investigate how changes in temperature affect the performance properties of these materials. The materials were tested for shock and vibration under four different temperatures (?17°C, 3°C, 23°C and 43°C). The results show that the properties of expanded polystyrene were the least influenced and those of expanded polyethylene were the most influenced by changes in temperature. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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研制了一种新型对接机构综合试验台环境模拟分系统,为空间对接机构提供高低温的试验环境,以便了解对接机构在不同的冷却状态、冷却速率条件下的性能及其对对接过程的影响。系统利用液氮喷射散流装置与可控硅控制的电加热器组合运行,为模拟试验提供高低温环境。同时利用高精度快速反应的气动调节装置和旁通分流方法维持试验空间的压力稳定,以消除附加压力对对接试验过程的影响。通过基于PLC的Fuzzy-PID多级控制和数据实时采集系统对环境模拟分系统的各关键控制点和监视点进行实时扫描。试验验证表明,建立的对接机构综合试验台环境模拟分系统能够满足试验过程对温度均匀度和压力稳定的要求,能为地面模拟对接过程提供合适的模拟环境。 相似文献
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S. Paul Singh Gary J. Burgess Jorge A Marcondes John R. Antle 《Packaging Technology and Science》1993,6(4):175-181
The dynamic and climatic environments inside the cargo holds of regrigerated ships carrying bananas from Central America to destinations in Europe and the United States were measured. The same environments inside individual packages of bananas were also measured for comparison. Among the variables studied were shock and vibration G-levels, temperature, humidity, and air velocity. Three different types of shipments were monitored: break-bulk, palletized, and containerized. The results show that the average G-levels are similar to those found on trailers and railcars and that the vibration levels in the packages themselves were amplified by up to as much as eight times. 相似文献
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本文以天宫二号空间材料炉多层隔热系统中纤维织物绝热材料为研究对象, 采用空间环境等效试验条件表征研究了织物有效导热系数随在轨温度和压强的变化, 结合微观传热机理对结果进行了分析, 根据表征结果对不同工况下炉内温度场进行了模拟。结果表明: 纤维织物有效导热系数随温度升高非线性增大, 压强越低, 增长越平缓; 随压强降低以指数函数趋势衰减且存在临界压强; 辐射与气相导热是影响空间环境下纤维织物传热性能的主要因素; 炉内温场计算值与匹配实验实测温度整体趋势吻合良好, 炉中心温度最大计算误差为实测温度的 1.3%。该方法更合理地评价了多层纤维材料在使用工况下的绝热性能, 从而有助于建立准确度更高的热仿真模型。 相似文献