Study of Chemical Processing of Carbonaceous Dust

我们研究了碳粉在星际介质中的化学处理。(1)金刚石粉的氢化。钻石是碳质粉尘的一种成分。我们在氢气气氛或氢等离子体中对不同粒度的金刚石粉末进行了加热。实验表明，纳米金刚石的C-H红外光谱不同于亚微米-微米级的金刚石。(2)碳质粉尘与氧、氮的表面反应。我们建立了一台射频发生器(13.56 MHz)的等离子体处理装置。利用该装置，我们尝试在合成的炭素材料(QCC)与N_2和O_2的等离子体气体反应后，在其表面生成OCN官能团，但没有检测到该官能团。我们将继续进行进一步的实验。(3)碳质粉尘中的碳同位素。合成了不同同位素比的碳质材料(QCC)，测量了它们的红外吸收光谱。利用这些结果，我们分析了各种天体的光谱。(Astron.&占星术。(4)粉尘形成过程研究--气体分析。利用质谱仪，我们分析了与QCC一起形成的气体。在不同的实验条件下，我们得到了不同的质谱图。(2003年日本天文学会年会)

We studied chemical processing of carbonaceous dusts in interstellar medium.(1)Hydrogenation of diamond powders. Diamond is a component of carbonaceous dusts. We heated diamond powders with different particle sizes in a hydrogen atmosphere or in a hydrogen plasma. Experiments showed that the infrared spectrum of C-H of nanodiamond was different from that of submicron-micron sized diamond. (Annual Meting of Japanese Astronomical Society, 2002, 2003, cluster-riyou-gijutsu-kennkyukai)(2)Surface reaction of carbonaceous dust with oxygen and nitrogen. We setup an apparatus of plasma processing with a radio frequency generator (13.56MHz). Using this apparatus, we tried to make a functional group of OCN on the surface of a synthesized carbonaceous material (QCC) after a reaction with plasmic gas of N_2 and O_2. However, we could not detected the functional group. We will continue the experiment further.(3)Carbon isotopes in carbonaceous dusts. We synthesized carbonaceous materials (QCC) with various isotopic rations of^<13>C/^<12>C and measured their infrared absorption spectra. Using the results, we analyzed spectra of various celestial objects. (Astron. & Astrophys. 407,551,2003)(4)Study for dust formation process -analysis of gases. Using a mass-spectrometer, we analyzed gases formed together with QCC. We obtained various mass-spectra under different experimental conditions. (Annual Meeting of Japanese Astronomical Society, 2003)