Structure of interstellar carbonaceous dusts and their surface.

星际碳质尘埃的结构及其表面。

• 批准号: 09640314
• 负责人: WADA Setsuko
• 金额: $ 1.66万
• 依托单位: The University of Electro-Communications
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09640314/
• 关键词: Interstellar Dust; Carbonaceous Material; Carbon Onion; Infrared Spectrum; Ultraviolet Spectrum; Synthesis; Plasma; 炭素質星間塵; 星間空間; 炭素; 紫外線; 変質

Quenched Carbonaceous Composite (QCC) is a carbonaceous material condensed from an ejecta of hydrocarbon plasma. A.Sakata and his colleagues have shown that QCC has a 220 nm absorption feature, a set of infrared absorption bands that correspond to the infrared emission features in reflection nebulae, HIT regions, and planetary nebulae, and exhibits visible fluorescence matching the extended red emission seen in reflection nebulae. These properties make Q CC a strong candidate material as a laboratory analog to the carbonaceous material in the interstellar medium.High-resolution transmission electron micrographs (HRTEM) revealed that the dark-QCC is a coagulation of carbonaceous onion-like particles. Each particle consists of multiple shells, and many of the particles have a void at the center. The HRTEM images implied that the particles have many defected sites in their structure.By exposuring of the QCC with hydrogen gas, the defected sites in the dark-QCC particles were reacted with hydrogen molecules easily. As a result, peak intensities of infrared absorption bands at 3.42, 3.51, 6.9, 7.3, 12.5mum were increased, However, the 220 nm absorbance peak of the dark-QCC was stable. On the other hands, the filmy-QCC did not react with hydrogen both under irradiation of uv (222nm) and under dark condition.In order to clarify molecular cloud chemistry, we need more studies about the surface of the candidate materials.

淬火碳质复合材料（QCC）是一种由碳氢化合物等离子体喷射物凝结而成的碳质材料。 A.Sakata 和他的同事证明，QCC 具有 220 nm 吸收特征，这是一组与反射星云、HIT 区域和行星状星云中的红外发射特征相对应的红外吸收带，并表现出与扩展红光发射相匹配的可见荧光见于反射星云。这些特性使 Q CC 成为一种强有力的候选材料，作为星际介质中碳质材料的实验室模拟。高分辨率透射电子显微照片 (HRTEM) 显示暗 QCC 是碳质洋葱状颗粒的凝结物。每个颗粒由多个壳组成，许多颗粒的中心有一个空隙。 HRTEM图像表明颗粒的结构中有许多缺陷位点。通过将QCC暴露在氢气中，暗QCC颗粒中的缺陷位点很容易与氢分子发生反应。结果，3.42、3.51、6.9、7.3、12.5μm处的红外吸收带的峰强度增加，但暗QCC的220nm吸收峰稳定。另一方面，薄膜-QCC在紫外线（222nm）照射和黑暗条件下均不与氢发生反应。为了阐明分子云化学，我们需要对候选材料的表面进行更多研究。

项目成果

Wada S.et al.: "Carbonaceous onion-like particles as a component of interstellar dust" Astron.& Astrophys.(in press). (1999)

Wada S.et al.：“作为星际尘埃成分的碳洋葱状颗粒”Astron。

Wada S, et al.: "Carbonaceous onion-like particles as a component of interstellar dust" Astron.& Astrophys.1999 in press.

Wada S 等人：“作为星际尘埃成分的碳洋葱状颗粒”Astron。

Wada S., Kaito C.et al.: "Carbonaceous onion-like particles as a component of interstellar dust" Astron.& Astrophys.(in press). (1999)

Wada S.、Kaito C.等人：“作为星际尘埃成分的碳洋葱状颗粒”Astron。