共查询到19条相似文献,搜索用时 53 毫秒
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论介绍了北京同步辐射X-射线荧光微束分析装置的最新进展,以及近年来在生物医学和石油地质领域的应用研究工作,重点报导了前不久在国内首次使用该方法,对单个流体包裹体探测的实验结果。 相似文献
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介绍了同步辐射微束X射线荧光分析的特点,主要的仪器设备和方法。介绍了在头发和病变组织中微量元素成分的扫描分析,细胞元素谱及其在外界物理、化学条件下的变化分析等。展示了同步辐射微束X射线荧光分析在生物医学研究中的广阔前景。 相似文献
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借助计算机模拟成像,通过分析不同情况下的图像重构,研究了抽样间距和投影数、重构算法、荧光测量等若干因素对图像重构质量的影响,并得出了一些有益的结果,对实际应用具有一定的参考意义。 相似文献
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本介绍了同步辐射及其特点,同步辐射微探针荧光分析的实验装置及北京同步辐射装置上开展的研究工作。 相似文献
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DENG Biao YU Xiaohan LIAiguo XU Hongjie 《核技术(英文版)》2007,18(5):257-260
A nondestructive X-ray analysis technique combining transmission tomography, fluorescence tomography and Compton tomography based on synchrotron radiation is described. This novel technique will be an optional experimental technique at SSRF's hard X-ray micro-focusing beamline under construction at present. An experimental result of combined X-ray tomography is obtained in NE-5A station of PF. The reconstructed images of test objects are given. 相似文献
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Jingke Qiu Biao DengQun Yang Fen YanAiguo Li Xiaohan Yu 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(22):2662-2666
Synchrotron-based X-ray micro-fluorescence (μ-SXRF) is a non-destructive analytical technique and has been widely used to detect and quantify the elemental composition of samples in their natural state. To determine the internal elemental distributions within samples, X-ray fluorescence microtomography has been developed based on the hard X-ray microprobe at beamline BL15U1 of the Shanghai Synchrotron Radiation Facility (SSRF) in Shanghai, China. This technique was applied to image the cross-sectional distributions of multiple elements within a single human hair, and its validity was evaluated by comparing the results with the elemental maps of a thin hair section obtained using the well-established μ-SXRF mapping method. Elemental images of S, Ca, Mn, Fe, Cu, and Zn within a virtual slice of the hair were reconstructed after the tomographic measurements. The tomographic images of heavy elements like Fe, Cu, and Zn were found to be in good agreement with the corresponding μ-SXRF maps. Light elements, such as S, however, represented different patterns due to non-negligible self-absorption in the sample, and sophisticated correction algorithms accounting for such effects are required for obtaining qualitatively and quantitatively more accurate images. Compared to μ-SXRF mapping, X-ray fluorescence microtomography reduces the sample preparation requirements and has been demonstrated in this work as being a more ideal and effective imaging modality to non-destructively mapping out the internal distribution of heavy elements within samples at the micrometer scale at the SSRF. 相似文献
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用于大尺寸样品的同步辐射硬X射线衍射增强成像方法研究 总被引:2,自引:1,他引:1
作为 X 射线相衬成像的方法之一,衍射增强成像方法由于能获得较高的信噪比及分辨率而引起了人们的研究兴趣。北京同步辐射装置(BSRF)形貌学实验站也开展了该方法的探索研究。此前的衍射增强成像方法中,当白光 X 射线光束横截面尺寸为 20 mm×10 mm 时,经过双晶单色器后最大只能获得横截面尺寸为20 mm×4 mm 的均匀单色 X 射线,从而造成成像区域减小。在对通常衍射增强成像光路排列分析的基础上,提出了一种新的光学排列几何并进行了衍射增强实验。应用新光学排列几何首次获得了与入射白光 X 射线尺寸相当的、大的成像光斑均匀区域,因而新光学排列几何更适合于大尺寸样品的研究工作。同时,该光学排列几何成像分辨率可以达到微米量级并且更方便于实验操作。 相似文献
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本文介绍一个为北京同步光源研制的高精度X射线衍射仪系统,它包括有精度为0.001°的转角仪、高计数率本领探测器、快电子学、计算机自动控制和在线数据获取,并给出了在转靶X光机上的实验结果。 相似文献
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LI Ming: Mark L. SCHLOSSMAN 《核技术(英文版)》2006,17(6):322-333
Synchrotron radiation X-ray scattering is a useful tool for structural characterization of liquid interfaces. Specular reflectivity provides precise measurement of the interfacial widths and of the ordering of surfactants adsorbed to these interfaces. Diffuse scattering gives information on phase transitions and domain formation in surfactant monolayers and on interfacial fluctuations confined by and coupled across fluidic films. 相似文献
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上海光源BL15U1束线的SRXRF定量分析 总被引:1,自引:0,他引:1
本文介绍了用于同步辐射X射线荧光(XRF)定量分析的基本参数法(FP)和MC模拟法。上海光源(SSRF)硬X射线微聚焦光束线(BL15U1)应用上述两种方法对样品进行定量分析,验证了方法的有效性并用定量分析结果计算了BL15U1光束线部分元素的荧光探测限。实验结果表明,对样品中μg/g量级元素含量的定量分析结果相对误差都在10%以内,而使用MC模拟法可以直观地比较不同参数下的模拟谱与实验谱,辅助实验参数的确定,从而减小参数引起的误差,得到更为准确的结果。此外,对BL15U1探测限的计算表明该光束线具备开展高性能荧光实验的能力。 相似文献
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Synchrotron radiation X-ray fluorescence (SRXRF) microprobe was used to ananlyse altered mineral muscovite and its surrounding feldspar in Yuerya gold deposit. The major, minor and trace elements of the two minerals were detected and analyzed. SRXRF analysis showed that the Yuerya muscovite had a complex chemical composition. containing K, Fe, Ca, Ti, Cr, Mn, Co, Cu, Zn and many trace or ultra-trace elements. Since muscovite resulted from the alteration of hydrothermal ore fluid acting on feldspar (plagioclase), the difference of chemical composition between the two minerals shows the components of ore fluid, which are characterized by the enrichment of alkaline and alkaline-earth metal elements K, Ca and ore-associated elements Fe, Cu, Zn. And gold. silver and platinum, invisible under microscope, were detected in some areas of muscovite but not found in feldspar. Especially platinum, a mantle material is rarely seen in the earth crust but now found in the gold deposit of magmatic sources; its appearance approves the idea of mantle flux participating in the gold mineralization, which suggests that the tectonic event controlling gold mineralization in the Yuerya district is a mantle phenomenon. 相似文献
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用同步辐射软X射线作为光源,可实现分子中某些原子芯能级的共振激发。而芯能级电子被共振激发到非占据分子轨道后,其去激发过程通常以旁观者俄歇过程为主。由于在旁观者俄歇过程中被激发的电子在随后的去激发过程中并不参与,而是保留在具有反键特性的非占据轨道中,这样的分子激发态一般有较陡的排斥势能面,所以它在紧随其后的离解与解吸过程中起着重要的作用。由于反键轨道一般定域在特定的化学键上,所以这一共振激发往往可引起分子中某些特定化学键的断裂。这就象一把“化学剪刀”一样,它可将吸附在基底表面吸附物质的某些碎片裁剪掉。通过芯能级共振激励离子解吸的实例,对其中的某些过程与机理进行探讨。 相似文献