All issues
Special Issue
Special Issue
Volume 78, Issue 3
Displaying 1-6 of 6 articles from this issue
- |<
- <
- 1
- >
- >|
-
Hisako HIRAI, Yukako UCHIHARA, Taro KAWAMURA, Yoshitaka YAMAMOTO, Take ...2002 Volume 78 Issue 3 Pages 39-44
Published: 2002
Released on J-STAGE: October 17, 2006
JOURNAL FREE ACCESSHigh-pressure experiments of argon hydrate and methane hydrate were performed using a diamond anvil cell in a pressure range of 0.2 to 10.0GPa at room temperature. In-situ X-ray diffractometry and optical microscopy revealed that two high pressure structures of argon hydrate, a primitive tetragonal structure and a body-centered orthorhombic structure, existed under pressures of up to 6.5GPa. The structural analysis showed that the tetragonal structure was composed solely of 14-hedra accommodating two argon atoms, and that the body-centered orthorhombic structure belonged to a“filled-ice”structure, i.e., a new type of structure in a water-guest system. As for methane hydrate, three high-pressure structures, a hexagonal structure, a primitive orthorhombic structure, and a body-centered orthorhombic structure, were found. The structural analysis indicated that the hexagonal structure was a modified structure of a hexagonal one reported at ambient pressure, and that the latter orthorhombic structure was the“filled-ice”structure.View full abstractDownload PDF (2320K) -
Ichiji NAMATAME, Hiroshi TOMODA, Daisuke MATSUDA, Noriko TABATA, Susum ...2002 Volume 78 Issue 3 Pages 45-50
Published: 2002
Released on J-STAGE: October 17, 2006
JOURNAL FREE ACCESSStreptomyces sp. K97-0239, a soil isolate, was found to produce inhibitors of lipid droplet formation in mouse peritoneal macrophages. Two compounds, K97-0239A and B, were isolated from the culture broth of the producing strain, and their structures were elucidated by spectroscopic analyses including various NMR experiments. They were cyclic lipopeptides comprising 2, 3-diaminopropionic acid, 4-(aminomethyl)-2, 2-dimethyl-5-oxo-1-imidazolidineacetic acid and phenylalanine/leucine as ring units, and 3-(13-hydroxytetradeca-2, 4-dienoylamino)-acrylic acid as lipophilic side chains. They caused a dose-dependent reduction in the number and size of cytosolic lipid droplets in macrophages at least up to 15μM without any cytotoxic effect on macrophages. [14C] Cholesteryl ester synthesis from [14C] oleic acid by macrophages was inhibited by K97-0239s with IC50 values of 1.5-1.7μM.View full abstractDownload PDF (3421K) -
Implications for the age and origin of eclogite xenolith from the Colorado PlateauTomohiro USUI, Katsura KOBAYASHI, Eizo NAKAMURA2002 Volume 78 Issue 3 Pages 51-56
Published: 2002
Released on J-STAGE: October 17, 2006
JOURNAL FREE ACCESSWe improved the U-Pb zircon dating method employing HR-SIMS by applying i) preparation of precise and homogeneous zircon standards by ID-TIMS, ii) simultaneous analysis of Pb isotopes by multi-collection system, and iii) use of a highly focused primary ion beam as small as 5μm in diameter. Using the improved HR-SIMS technique, U-Pb ages of zircons in an eclogite xenolith from the Colorado Plateau were determined. Zircon occurs as small inclusions (<20μm) in most constituent minerals. Ten zircons were measured, and the concordant analyses of these zircon data yielded a weighted mean value of 65.2±0.7Ma for the age of crystallization. Petrographic and geochemical observations suggest that this zircon age represents the age of initial subduction of basaltic oceanic crust. We conclude that the eclogite xenolith was a fragment of basaltic oceanic crust subducted to >90km depth along a cold geotherm with a subduction rate of >2cm/y in Tertiary.View full abstractDownload PDF (3351K) -
Yoshiaki ARATA, Yue-Chang ZHANG2002 Volume 78 Issue 3 Pages 57-62
Published: 2002
Released on J-STAGE: October 17, 2006
JOURNAL FREE ACCESSIt was confirmed that nanometer-sized metal powder (atom clusters or simply clusters) can absorb an extremely large amount of deuterium/hydrogen atoms more than 300% against the number density of host metal. Within such clusters, the bonding potential widely changes from the center region to peripheral ones, so that the zig•zag atom-chains are always formed dynamically around the average position of atoms and the degree of filling up of the constituent atoms for the fcc type metal reduces to about 0.64 from 0.74 in bulk metal, i.e., vacant space increases to 0.36 from 0.26. As a result, a large amount of deuterium /hydrogen atoms are instantly dissolved into such host-clusters at room temperature. Furthermore, “metallic deuterium lattice”(or hydrogen one) including locally the“deuterium-lump”with the ultrahigh density is formed with body centered cuboctahedral structure which belongs to a unit cell of the host lattice, while such event cannot be realized at all within bulk metals. It seems that nuclear fusion in solid (“solid fusion”) takes place in the highly condensed“deuterium-lump”inside each unit cell of the“metallic deuterium lattice”(or mixed hydrogen one) which is formed inside each cell of the host metal lattice. It is considered, therefore, that each unit cell of the host lattice corresponds to minimum units of“solid fusion reactor”. In order to achieve“solid fusion”, just the generation of the ultrahigh density“deuterium-lump”(simply“pycnodeuterium-lump”) coagulated locally inside unit cell of the host lattice and/or the highly condensed metallic deuterium lattice should be an indispensable condition.View full abstractDownload PDF (1070K) -
Yoshiaki ARATA, Yue-Chang ZHANG2002 Volume 78 Issue 3 Pages 63-68
Published: 2002
Released on J-STAGE: October 17, 2006
JOURNAL FREE ACCESSUsing intense ultrasonic cavitation effect, metals kept in heavy water were changed to nanometer-sized fine powders and simultaneously condensed a large amount of deuteriums for 1-2 days. Mass analyses of gases released from the remnant metal powders revealed existence of 3He and 4He which were produced by the deuterium nuclear fusion reacted inside the metals. On the other hand, simultaneously generated excess energy were recognized in only D2O working liquid, using the working liquids of D2O or H2O-water in which immersed metal foils kept inside a sono-vessel.View full abstractDownload PDF (4724K) -
Development of a method for highly efficient and sensitive discrimination of chiral alcoholsHiroshi OHRUI, Hanae TERASHIMA, Keiichiro IMAIZUMI, Kazuaki AKASAKA2002 Volume 78 Issue 3 Pages 69-72
Published: 2002
Released on J-STAGE: October 17, 2006
JOURNAL FREE ACCESSVery potent fluorescent chiral labeling reagents for alcohols, (R, R)-and (S, S)-2-(anthracene-2, 3-dicarboximido)cyclohexanecarboxylic acids, were developed. By labeling with them, the enantiomeric discriminations of primary alcohols having a methyl branching at the carbon from 2 to 9 by 1H-NMR and from 2 to 16 by HPLC were achieved. Further, HPLC separations of all four optical isomers of methyl branched secondary alcohols and enantiomers of 9-nonadecanol were also achieved.View full abstractDownload PDF (328K)
- |<
- <
- 1
- >
- >|