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An electrostatic levitator was developed for the structural analysis of high-temperature and undercooled liquids by X-ray diffraction. The apparatus can be used to investigate the structure of metallic, semiconductor, and ceramic liquids. Samples of zirconium, silicon, and alumina in their liquid phases could be kept levitated for more than one hour with this apparatus. This was sufficiently long to perform a detailed analysis of the liquid structure by X-ray diffraction techniques., 資料番号: AA0063323003, レポート番号: JAXA-RR-06-015E

Applying a combined analytical method specialized for cosmic-dust research, we have characterized mineralogy of individual mineral particles in 2A and 2B powder test samples that were prepared for the second analysis competition of the Hayabusa mission. Thirty-eight mineral particles mostly less than 300 micrometer in diameter and ten fine-grained mineral aggregates less than 200 micrometer in diameter were picked out from the test samples. Individual samples were X-rayed using synchrotron radiation to have powder X-ray diffraction patterns for identification of constituent minerals. The relative abundances of major constituent minerals in individual samples were determined by applying the Rietveld refinement to diffraction patterns. The X-rayed samples were polished and analyzed by a Scanning Electron Microscope (SEM) for imaging and an Electron-Probe MicroAnalyzer (EPMA) for quantitative concentrations of thirteen elements. Finally, ten selected samples were thinned by ultramicrotomy, argon ion bombardment, or Focused Ion Beam (FIB) method for detailed mineralogical characterization by Transmission Electron Microscopy (TEM). Small plagioclase compositions are determined by Analytical Electron Microscopy (AEM) using a cold sample stage. The bulk mineralogy, chemical composition, and nano-scale textures were all obtained from a single small particles less than 300 micrometer and the total mass of each test sample we used for the present study was only 100 microgram. Therefore, we can accomplish complete mineral characterization using very small quantity of regolith materials of the asteroid Itokawa, when the initial analysis of the returned samples is undertaken. The results showed that 2A powder sample consists mainly of olivine (Fa(sub 15.1+/-0.6) on an average), low-Ca pyroxene (Fs(sub 13.9+/-0.7) on an average), plagioclase, troilite, and kamacite with minor amounts of high-Ca pyroxene, taenite, chromite, Ca-phosphate, and alkali feldspar. The compositions and compositional variations of silicates and the minor element abundances in FeNi metals indicate that the 2A sample bears a close resemblance to H chondrites with petrologic type four to five. Fe/Mg ratios of both olivine and low-Ca pyroxene in the 2A sample correspond to the lowest-end of Fe/Mg variation for H chondrites, suggesting that it is a sample of most reduced type of H chondrites. In addition, the 2A samples contain small amounts of artificial contamination such as quartz-calcite composites, Ni-free Mn-bearing iron metals, and carbonaceous particles like epoxy resin. These particles probably got mixed during preparation of the 2A sample powder from a meteorite. The 2B sample is coarse particles that are composed mainly of metallic phases such as kamacite. Olivine and low-Ca pyroxene are also contained, but metal/silicate ratio of the 2B test sample is apparently higher than that of the 2A test sample. However, Mg/Fe ratios of silicate (Fa(sub 15.8+/-0.5) and Fs(sub 14.4+/-0.7) on an average) and the presence of well-defined chondrules suggest that the 2B sample is also similar to H chondrites with petrologic type four to five. All mineralogical characteristics, except for the mode of occurrence of FeNi metals, are very similar between 2A and 2B test samples. This may indicate that the two test samples were prepared from the same meteorite. The high metal/silicate ratio of the 2B test sample is therefore artifact, most probably the results of mechanical separation of magnetic components from a powder of an H chondrite., 資料番号: AA0063920001, レポート番号: JAXA-SP-05-021E

X線・中性子散乱法と静電浮遊炉を組み合わせることにより、超高温や過冷却液体の構造を精密に測定することが可能である。本研究は、シリコンやジルコニウムなど高温金属液体の液体構造を測定するために、構造解析用の静電浮遊炉を新たに開発し、高輝度放射光および中性子線を用いた散乱実験を試みた。実験の結果、これらの液体の静的構造因子(過冷却液体状態を含む)を高精度に測定することができた。, The structure of undercooling liquid state is one of the important subjects of materials science. The levitation techniques are powerful tools for the investigation of undercooled liquids. In this research, we developed the electrostatic levitation furnace for the liquid structure analysis due to the neutron and x-ray diffraction methods. The apparatus was tested by using a synchrotron radiation facility, a laboratory X-ray source and a reactor. The structures of several kinds of materials were investigated and the liquid structures can be measured with high precision., 資料番号: AA0049301004, レポート番号: JAXA-RR-05-034E

The Si(0.5)Ge(0.5) bulk crystals growth has been challenged. Si-Ge homogeneous single crystals are difficult to grow so far. In the present research, the Traveling Liquidus-Zone method (TLZ method) which was invented in the group as a new crystal growth method to the growth of Si-Ge has been applied. The diameter of grown crystal was 2 mm and the length was 15 mm. Crystals were well seeded and had the orientation of silicon seeds in spite of the large lattice mismatch. The compositional variation of the crystals was very small and the composition was in the mole fraction range of 0.5 +/- 0.016 in germanium. The lattice constant determined by the X-ray powder diffraction was 55.38 nm., 資料番号: AA0048451001, レポート番号: JAXA-RR-04-022E

資料番号: AA0063323000, レポート番号: JAXA-RR-06-015E

アポフェリチンタンパク質を材料とし、相図の作成、結晶品質評価などを行った。結晶化駆動力を変動させ、ファセット結晶、骸晶などを育成し、ロッキングカーブ幅計測を行った。, Crystal growth studies using apoferritin was carried out. The rocking curve width of facet and skeletal crystals were measured., 資料番号: AA0063335000, レポート番号: JAXA-SP-06-028

資料番号: AA0063920000, レポート番号: JAXA-SP-05-021E

資料番号: AA0049301000, レポート番号: JAXA-RR-05-034E

タンパク質結晶の成長と完全性に及ぼす不純物の影響を、ニワトリ卵白リゾチーム結晶を用いて明らかにした。, The impurity effects on crystal growth and perfection was systematically studied with lysozyme and lysozyme dimer. X-ray diffraction experiment, rocking width measurement, X-ray topography, etching, AFM observation and fluorescence experiments revealed that impurities actually degrade the crystal perfection, and dislocations are the main cause., 資料番号: AA0048459000, レポート番号: JAXA-RR-04-051

国際宇宙ステーションロシアサービスモジュール利用微小粒子捕獲実験および材料曝露実験(SM/MPAC&SEED)の2回の回収エアロジェルの1次評価概要については、北澤ら、Neish et al.において報告されている。本発表では、我々は第2回回収のエアロジェルに観察された顕著な試料捕獲トラックのひとつから捕獲された粒子の詳細分析について報告する。実際に大気圏外において曝露を行ったエアロジェルから捕獲粒子を取り出して分析を行った研究は、最近までMirに搭載したエアロジェルから捕獲粒子を取り出して分析した例(Hoerz et al., 2000)などわずかであった。しかし、Stardust探査機に搭載したエアロジェルで捕獲した研究例が今後爆発的に増加すると考えられる。この場合、捕獲粒子に各種非破壊分析を行うのでは、捕獲粒子について誤った結論を導く可能性があるため、エアロジェルから粒子を取り出しての分析は重要である。, 資料番号: AA0063224004, レポート番号: JAXA-SP-06-021