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采用不同沉淀剂Na3_PO_4、Na_2HPO_4、NaH_2PO_4通过水相沉淀法制备Ag_3PO_4产物并考察其可见光催化脱除NO_x的性能。结果表明,不同沉淀剂对Ag_3PO_4产物的晶相组成、形貌、光学性能和光催化活性有显著影响,其中Na_2HPO_4制备出的不规则状纯相Ag_3PO_4样品具有更高的光催化脱除NO_x的活性。 相似文献
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In the practical application, a wide-angle absorption with simple structure is still crucial property of metamaterial absorbers (MAs). A single-band infrared MA is introduced to analyze the angle insensitive mechanism. Numerical simulation reveals that a perfect absorption peak with 99.9% (7.55 μm) is achieved at normal incidence, as well as the absorptivity is respectively 69.7% (7.46 μm) and 93.5% (7.46 μm) for transverse electric (TE) and transverse magnetic (TM) modes at 70° incidence. By changing substrate thickness, the absorption ratio at 70° is increased to 91% (7.46 μm) for TE mode. Our design can also keep the good absorption stability for the geometric parameters. The Ez-field distributions for different incident angles are given to investigate the physical mechanism. The designed MA can realize good wide-angle tolerance. This MA owns great applications, including infrared spectroscopy, solar harvester and plasmonic sensors. 相似文献
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本文通过真空熔炼,在纯镍N6中添加稀土元素Ce。采用金相显微镜、扫描电镜、透射电镜等技术,研究了稀土Ce对纯镍N6中夹杂物、组织和断口的影响。结果表明,添加稀土Ce能够有效净化纯镍N6熔体,使熔体中夹杂物的数量显著减少,改变夹杂物的形状,减小夹杂物尺寸,但收得率仅为21%;少量Ce的氧化物夹杂呈菱形而残留在镍基体中,分布在晶界处;添加稀土Ce的N6板材拉伸断口韧窝均匀,且少有孔洞;部分稀土Ce与Ni生成金属间化合物,在塑性变形过程中容易发生破碎,且冶金结合较弱,容易形成裂纹源,对N6板材的力学性能有严重影响。 相似文献
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精铁矿粉催化氧化法生产α-Fe_2O_3反应过程研究 总被引:1,自引:1,他引:0
介绍以陕西、河北、湖北等几种国内高纯铁矿及伴生铁矿粉为原料 ,通过催化氧化法生产电子工业用的高品位α Fe2 O3工艺过程研究 ,从理论和试验两方面讨论各种工艺参数对反应过程的影响 ,得出反应过程优化的工艺条件 :铁矿粉粒度 3 0 0— 3 2 5目 ,反应温度 82 0— 940℃ ,反应时间 4— 5h ,催化剂用量 0 .5 %— 1.0 %。产品的纯度大于 98.0 % ,收率大于 98.5 %。产品磁学性能可达到软磁铁氧体电子器件的要求 相似文献