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Mass-selected C60 beam produced by laser ablation was accelerated and bombarded the (0001) surface of highly oriented pyrolitic graphite and (111) surface of gold single crystal. The samples were characterized by STM. The STM images showed that, the deposited species collapsed and formed planar structure on the solid surface, but the collapsed species were not dissociated and well oriented on the surface. Both positive and negative C60 ions were observed in the desorption mass spectra, confirming that the species collapsed on the solid surface are still the C60 clusters. 相似文献
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常用的气体分析质谱仪使用四极杆质谱作为分析器,分辨率一般低于300,无法解决同质量数离子带来的干扰问题.本实验自行研制了一种小型高分辨气体分析质谱仪,它采用电子轰击离子源反射式飞行时间质量分析器.仪器腔体总长45 cm,在m/z 28的位置,质量分辨率达到3000(Full width at half maximum,FWHM),实现了CO和N2的半峰谷分离;在m/z 69的位置,仪器分辨率达到5000(FWHM).在直接大气压进样条件下,可以检测到空气中136Xe(含量7.8 μ g/m3)和80Kr(含量2.8 μg/m3).使用ADC采集时,仪器的动态范围为1 06.该仪器将作为高端气体质谱仪,应用于过程监测在线分析、环境有机挥发物研究、热分析质谱及催化反应监测等领域. 相似文献
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An experiment facility has been set up for the study of metal cluster compounds in our laboratory, which consists of a nano-electrospray ionization source, an ion transmission and focus system, and a reflectron time-of-flight mass spectrometer. Taking advantage of the nano-electrospray ionization source, polyvalent ions are usually produced in the “ionization” process and the obtained mass resolution of the equipment is over 8000. The molecular ion peaks of metal cluster compounds [Au20(PPhpy2)10Cl2](SbF6)4, where PPhpy2=bis(2-pyridyl)phenylphosphine, and [Au6Ag2(C)L6](BF4)4, where L=2-(diphenylphosphino)-5-methylpyridine, are distinguished in the respective mass spectrum, accompanied by some fragment ion peaks. In addition, the mass-to-charge ratios of the parent ions are determi-nated. Preliminary results suggest that the device is a powerful tool for the study of metal cluster compounds. It turns out that the information obtained by the instrumentation serves as an essential supplement to single crystal X-ray diffraction for structure characterization of metal cluster compounds. 相似文献
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设计了一套紧凑的光电子成像装置,它包括解离式光电子贴附负离子源、垂直安装的高分辨阈值光电子速度成像装置和线性飞行时间质谱仪.紫外光辐射金属表面诱导低能光电子发射,再通过低能电子贴附超声分子束产生高强度和冷的负离子源.结合这种负离子源和飞行时间质谱-光电子成像仪装置,仪器的质量分辨能达到200左右,能量分辨优于3%(即对1 eV动能的电子,分辨达到30 meV).此外,使用该实验装置获得了CH3S-和S2-在611.46 nm下的低能阈值光电子成像结果.同时得到了CH3S和S2的更精确的电子亲和势分别为1.8626±0.0020和1.6744±0.0035 eV.初步的结果证明了该装置对研究阈值光电子成像精确测量光电子亲和势非常有效 相似文献
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固体酸催化条件下碳纳米管的形成 总被引:10,自引:0,他引:10
将正丁烯在不含金属微粒的催化剂上热解产生了碳纳米管.所用的催化剂是固体酸的氟促进的γ-Al2O3和分子筛型的HZSM-5.实验发现,这些固体酸催化剂热解产生碳纳米管所需的温度较低,碳纳米管的产生与催化剂的酸度和酸性位有一定的关联,而且所产生的碳纳米管的结构形态也比较独特. 相似文献