Author
Dieter Heymann
Other affiliations: University of Chicago, University of Amsterdam
Bio: Dieter Heymann is an academic researcher from Rice University. The author has contributed to research in topics: Meteorite & Chondrite. The author has an hindex of 30, co-authored 121 publications receiving 4616 citations. Previous affiliations of Dieter Heymann include University of Chicago & University of Amsterdam.
Topics: Meteorite, Chondrite, Allende meteorite, Chondrule, Fullerene
Papers published on a yearly basis
Papers
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TL;DR: A readily scalable purification process capable of handling single-wall carbon nanotube (SWNT) material in large batches, which should greatly facilitate investigation of material properties intrinsic to the nanotubes.
Abstract: We describe, in detail, a readily scalable purification process capable of handling single-wall carbon nanotube (SWNT) material in large batches. Characterization of the resulting material by SEM, TEM, XRD, Raman scattering, and TGA shows it to be highly pure. Resistivity measurements on freestanding mats of the purified tubes are also reported. We also report progress in scaling up SWNT production by the dual pulsed laser vaporization process. These successes enable the production of gram per day quantities of highly pure SWNT, which should greatly facilitate investigation of material properties intrinsic to the nanotubes.
1,400 citations
TL;DR: Carbonaceous chondrites noble gases measurement by mass spectroscopy, discussing compositional trends and origins as mentioned in this paper, discussed compositional trend and origins of chondrite noble gases.
380 citations
TL;DR: In this article, the origin and history of the Hypersthene chondrite were studied using noble gas content and shock and reheating by X-ray diffraction, and the results showed that the noble gas was positively correlated with the temperature of the hypersthene.
345 citations
TL;DR: In this article, the solubilities of C60 and C70 at 25°C in seven normal alcohols obey the relationship InY = a + bX + cX2, where Y is solubility and X is the Hildebrand parameter of the solvent.
Abstract: The solubilities of C60 and C70 at 25°C in seven normal alcohols obey the relationship InY = a + bX + cX2, where Y is solubility and X is the Hildebrand solubility parameter of the solvent. Extrapolation to the solubility parameter of water yields solubilities in water of 1.3′10−11 (C60) and 1.3′10−10(C70) ng/ml with an uncertainty of one order of magnitude.
136 citations
TL;DR: High-pressure liquid chromatography with ultraviolet-visible spectral analysis of toluene extracts of samples from two Cretaceous-Tertiary boundary sites in New Zealand has revealed the presence of C60, which may have originated in the extensive wildfires that were associated with the cataclysmic impact event that terminated the Mezozoic era.
Abstract: High-pressure liquid chromatography with ultraviolet-visible spectral analysis of toluene extracts of samples from two Cretaceous-Tertiary (K-T) boundary sites in New Zealand has revealed the presence of C 60 at concentrations of 0.1 to 0.2 parts per million of the associated soot. This technique verified also that fullerenes are produced in similar amounts in the soots of common flames under ambient atmospheric conditions. Therefore, the C 60 in the K-T boundary layer may have originated in the extensive wildfires that were associated with the cataclysmic impact event that terminated the Mezozoic era about 65 million years ago.
132 citations
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TL;DR: In this article, new abundance tables have been compiled for C1 chondrites and the solar photosphere and corona, based on a critical review of the literature to mid-1988.
10,322 citations
TL;DR: Many potential applications have been proposed for carbon nanotubes, including conductive and high-strength composites; energy storage and energy conversion devices; sensors; field emission displays and radiation sources; hydrogen storage media; and nanometer-sized semiconductor devices, probes, and interconnects.
Abstract: Many potential applications have been proposed for carbon nanotubes, including conductive and high-strength composites; energy storage and energy conversion devices; sensors; field emission displays and radiation sources; hydrogen storage media; and nanometer-sized semiconductor devices, probes, and interconnects. Some of these applications are now realized in products. Others are demonstrated in early to advanced devices, and one, hydrogen storage, is clouded by controversy. Nanotube cost, polydispersity in nanotube type, and limitations in processing and assembly methods are important barriers for some applications of single-walled nanotubes.
9,693 citations
TL;DR: A review of recent advances in carbon nanotubes and their composites can be found in this article, where the authors examine the research work reported in the literature on the structure and processing of carbon Nanotubes.
4,709 citations
TL;DR: Only the alternating pattern of single-double carbon bonds within the sp2 carbon ribbons provides a satisfactory explanation for the experimentally observed blue shift of the G band of the Raman spectra relative to graphite.
Abstract: We investigate Raman spectra of graphite oxide and functionalized graphene sheets with epoxy and hydroxyl groups and Stone−Wales and 5−8−5 defects by first-principles calculations to interpret our experimental results. Only the alternating pattern of single−double carbon bonds within the sp2 carbon ribbons provides a satisfactory explanation for the experimentally observed blue shift of the G band of the Raman spectra relative to graphite. To obtain these single−double bonds, it is necessary to have sp3 carbons on the edges of a zigzag carbon ribbon.
4,000 citations
TL;DR: Arc-synthesized single-walled carbon nanotubes have been purified through preparative electrophoresis in agarose gel and glass bead matrixes and promise to be interesting nanomaterials in their own right.
Abstract: Arc-synthesized single-walled carbon nanotubes have been purified through preparative electrophoresis in agarose gel and glass bead matrixes. Two major impurities were isolated: fluorescent carbon and short tubular carbon. Analysis of these two classes of impurities was done. The methods described may be readily extended to the separation of other water-soluble nanoparticles. The separated fluorescent carbon and short tubule carbon species promise to be interesting nanomaterials in their own right.
3,357 citations