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超软X射线流气式正比计数管 总被引:2,自引:0,他引:2
介绍了一种用于测量183~933eV超软X射线的圆柱形、侧窗式、流气式正比计数管,工作气体是0.11MPa的P-10气体或氦气-丙烷混合气体。计数管内径为φ25mm,直径为φ0.3mm的入射窗是由厚度80~90μgcm~2聚乙烯甲醛制成的。该计数管的特点:(1)薄窗,对软X射线透过率高。(2)流气式,工作寿命长。(3)能量分辨率好。(4)计数率高(1×10~(14)个/s)。(5)可测能区宽(0.183~10keV)。(6)可以方便更换窗膜材料、厚度及窗口直径。近几年来该计数管已经为高强度低能X光源提供较好监测。 相似文献
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Herein, we demonstrate that silica films with perpendicular macroporous channels and accessible ordered mesopores can be conveniently prepared. The hierarchical macroporous–mesoporous silica films are synthesized by using zinc oxide nanorod array as macroporous template and CTAB surfactant as mesoporous template. In basic surfactant-containing solution, ordered mesoporous silica shells homogeneously grow on the zinc oxide nanorod array. The growth of the mesostructures do not require any chemical modification for the zinc oxide nanorod, which opens a new way for preparing hierarchical silica films with perpendicular mesochannels. The prepared hierarchical macroporous–mesoporous silica films possess a uniform thickness of 2 mm, large perpendicular macropores with a length of 1.8 mm and a width of 80 nm, and accessible ordered mesopores. Separation experiment demonstrates that this macroporous–mesoporous film can effectively separate biomolecules with different sizes. 相似文献
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Wu Jinxiu Qi Yuanhao Liu Zhaogang Jia Huiling Hu Yanhong Feng Fushan 《Journal of solution chemistry》2022,51(1):14-30
Journal of Solution Chemistry - The interaction between Dy(Ш)/Rutin complexes and bovine serum albumin (BSA) was studied by fluorescence, ultraviolet (UV) absorption, three-dimensional... 相似文献
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通过采用碳酸镧(铈、镨)为前驱体,经氟化、高温焙烧、机械湿磨的方法得到稀土抛光粉,研究了不同掺镨量对稀土抛光粉的物相结构、表面形貌、粒度、密度、抛蚀量的影响。通过XRD分析得出结论:La2O3,Pr6O11固溶于CeO2的晶格结构中,并且出现了新的物相LaOF;随镨掺量的增大,LaOF的衍射峰强度不断增加,晶化程度不断增加;CeO2的XRD特征峰向左偏移,晶胞参数变大,晶面间距变大。通过粒度分析得出结论:随镨掺量的增加,抛光粉的中位粒径出现了先减小后增大的规律性变化。通过抛蚀量测试得出结论:随镨掺量的增加,抛光粉的抛蚀量出现了先增大后减小的变化。掺镨稀土抛光在镨含量为4.8%时,具有最小的中位粒径、较好的表面形貌和最大的抛蚀量。 相似文献
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Mei Li Zhaogang Liu Yanhong Hu Zhenxue Shi 《Colloids and surfaces. A, Physicochemical and engineering aspects》2008,320(1-3):78-84
In this work large CeO2 particles were prepared using H2C2O4 and NH4HCO3 as precipitators. The effects of feeding mode and speed, stirring speed, aging time, precipitate and calcination temperature and precipitation method on physicochemical properties of CeO2 were studied when the precipitator was H2C2O4. By the NH4HCO3 precipitation method, the effects of adding inoculating crystals and additives on particle size, loose density and fluidity of CeO2 were investigated. Under optimized conditions, large CeO2 particles with high loose density and good fluidity of can be prepared by either H2C2O4 or NH4HCO3 precipitation method. SEM also investigates the morphology of the particles prepared by both methods. The results show that physicochemical properties of CeO2 particles prepared by the NH4HCO3 precipitation method are not as good as those of CeO2 particles prepared by the H2C2O4 precipitation method. However, both methods are suitable for industrial production due to their simple processes, low equipment investment and ease for industrial development. Our results show that large rare earth particle can be prepared by the optimized conventional methods. This study provided a useful method to prepare of large rare earth particles. 相似文献
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Xu Peng Liang Juan Cao Xiaoyong Tang Jingen Gao Juan Wang Liying Shao Wei Gao Qinwei Li Wei Teng Zhaogang 《Research on Chemical Intermediates》2016,42(12):8321-8328
Research on Chemical Intermediates - In this paper, we demonstrate a facile electroless plating method for fabricating silver nanoparticles deposited onto hollow mesoporous silica microspheres... 相似文献
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The generation process of silver chloride was studied using dynamic speckle methods including speckle size measurement and speckle contrast measurement. The quantity and size changes of the sedimentation particles in the illuminating region were investigated and analyzed. 相似文献