Search Results - (Author, Cooperation:C. Halpin)
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1Latest Papers from Table of Contents or Articles in PressR. Vanholme ; I. Cesarino ; K. Rataj ; Y. Xiao ; L. Sundin ; G. Goeminne ; H. Kim ; J. Cross ; K. Morreel ; P. Araujo ; L. Welsh ; J. Haustraete ; C. McClellan ; B. Vanholme ; J. Ralph ; G. G. Simpson ; C. Halpin ; W. Boerjan
American Association for the Advancement of Science (AAAS)
Published 2013Staff ViewPublication Date: 2013-08-21Publisher: American Association for the Advancement of Science (AAAS)Print ISSN: 0036-8075Electronic ISSN: 1095-9203Topics: BiologyChemistry and PharmacologyComputer ScienceMedicineNatural Sciences in GeneralPhysicsKeywords: Arabidopsis/*enzymology/genetics ; Arabidopsis Proteins/*chemistry/genetics ; Carboxylic Ester Hydrolases/*chemistry/genetics ; Glucose/chemistry ; Lignin/*biosynthesis ; Metabolic Networks and Pathways ; Mutation ; Shikimic Acid/chemistry ; Substrate SpecificityPublished by: -
2Articles: DFG German National LicensesStaff View
ISSN: 0032-3888Keywords: Chemistry ; Chemical EngineeringSource: Wiley InterScience Backfile Collection 1832-2000Topics: Chemistry and PharmacologyMechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision MechanicsPhysicsNotes: The Halpin-Tsai equations are based upon the “self-consistent micromechanics method” developed by Hill. Hermans employed this model to obtain a solution in terms of Hill's “reduced moduli”. Halpin and Tsai have reduced Hermans' solution to a simpler analytical form and extended its use for a variety of filament geometries. The development of these micromechanic's relationships, which form the operational bases for the coniposite analogy of Halpin and Kardos for semi-crystalline polymers, are reviewed herein.Additional Material: 4 Ill.Type of Medium: Electronic ResourceURL: -
3Articles: DFG German National LicensesStaff View
ISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: The growth and optical band gaps of heteroepitaxial layers of the ternary In1−xGaxSb [0≤x≤1] on (100)GaAs is reported. The epilayers, prepared by metalorganic magnetron sputtering using trimethyindium, trimethylgallium, and a sputtered antimony beam, showed good structural and surface morphologies despite a lattice mismatch between substrate and epilayer of 9%–14%. Secondary ion mass spectrometry analysis indicated a background carbon level in proportion to the gallium concentration. The high levels of carbon were not present in the InSb layers prepared using TMI. All films showed optical absorptions characteristic of direct gap semiconductors. The bowing parameter for the system is somewhat lower than that observed for the corresponding bulk material and may be related to compressive stress in the layers.Type of Medium: Electronic ResourceURL: -
4Articles: DFG German National LicensesStaff View
ISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: Metalorganic magnetron sputtering has been used to deposit polycrystalline and homoepitaxial films of indium antimonide. In this technique a metal antimony target is magnetron sputtered in a reactive vapor of trimethylindium (TMI). Stoichiometric layers of indium antimonide could be deposited for all growth temperatures studied (20–370 °C). However, below 250 °C the films were either amorphous or composed of very small crystallites. Above 290 °C the layers were epitaxial as determined from the electron channeling patterns observed. For these layers the growth rate was controlled by the TMI flow with the excess antimony flux acting to stabilize the surface. The surface morphology was excellent with "mirrorlike'' surfaces except at high TMI flows where indium surface droplets were formed.Type of Medium: Electronic ResourceURL: -
5Articles: DFG German National LicensesRao, T. Sudersena ; Halpin, C. ; Webb, J. B. ; Noad, J. P. ; McCaffrey, J.
[S.l.] : American Institute of Physics (AIP)
Published 1989Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: The effect of substrate temperature and III/V ratio on the growth rate and surface morphology of heteroepitaxial InSb films grown on GaAs(100) using metalorganic magnetron sputtering has been studied. The surface morphology showed a strong dependence on growth temperature and III/V ratio. Films with "mirrorlike'' surfaces could be routinely obtained for deposition temperatures near 400 °C. For films grown above 300 °C, the growth rate increased with increasing trimethylindium flow, at constant antimony sputter power, and exhibited a peak near 400 °C. In this region the growth rate was thermally activated with an observed activation energy of 0.24 eV. Above 400 °C the growth rate decreased with increasing temperature. The surface morphology of these higher-temperature layers indicated a selective etching process as the mechanism for growth rate reduction. Cross-sectional transmission electron microscopy studies indicated a defect density in excess of 1011 cm−2 at the InSb/GaAs interface which decreased to 4.0×109 cm−2 at a distance of 0.3 μm from the interface.Type of Medium: Electronic ResourceURL: -
6Articles: DFG German National LicensesStaff View
ISSN: 0014-5793Keywords: Chloroplast ; Leucoplast ; Processing ; Protein transport ; Thylakoid lumenSource: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyChemistry and PharmacologyPhysicsType of Medium: Electronic ResourceURL: -
7Articles: DFG German National LicensesCharacterization of heteroepitaxial InSb films on GaAs prepared by metalorganic magnetron sputteringStaff View
ISSN: 0040-6090Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: PhysicsType of Medium: Electronic ResourceURL: -
8Articles: DFG German National LicensesGoffner, D. ; Joffroy, I. ; Grima-Pettenati, J. ; Halpin, C. ; Knight, M. E. ; Schuch, W. ; Boudet, A. M.
Springer
Published 1992Staff ViewISSN: 1432-2048Keywords: Cinnamyl alcohol dehydrogenase (isoforms) ; Eucalyptus ; Lignin ; XylemSource: Springer Online Journal Archives 1860-2000Topics: BiologyNotes: Abstract Two distinct isoforms of cinnamyl alcohol dehydrogenase, CAD 1 and CAD 2, have been purified to homogeneity from xylem-enriched fractions of Eucalyptus gunii Hook and partially characterized. They differ greatly in terms of both physical and biochemical properties, and can be separated by hydrophobic interaction chromatography on Phenyl Sepharose CL-4B. The native molecular weight of of CAD 1 is 38 kDa as determined by gel-filtration chromatography on Superose 6, and this isoform is likely to be a monomer since it yields a polypeptide of 35 kDa upon sodium dodecyl sulfatepolyacrylamide gel electrophoresis. It has a low substrate affinity for coniferyl and p-coumaryl alcohols and their corresponding aldehydes. No activity with sinapyl aldehyde and alcohol was detected. The more abundant isoform is CAD 2, which has a native molecular weight of 83 kDa and is a dinier composed of two subunits of slightly different molecular weights (42–43 kDa). These subunits show identical peptide patterns after digestion with N-chlorosuccinimide. The isoform, CAD 2, has a high substrate affinity for all the substrates tested. The two isoforms are immunologically distinct as polyclonal antibodies raised against CAD 2 do not cross-react with CAD 1. The characterization of two forms of CAD exhibiting such marked differences indicates their involvement in specific pathways of monolignol utilisation.Type of Medium: Electronic ResourceURL: -
9Articles: DFG German National LicensesPurification and characterization of isoforms of cinnamyl alcohol dehydrogenase fromEucalyptus xylemGoffner, D. ; Joffroy, I. ; Grima-Pettenati, J. ; Halpin, C. ; Knight, M. E. ; Schuch, W. ; Boudet, A. M.
Springer
Published 1992Staff ViewISSN: 1432-2048Keywords: Cinnamyl alcohol dehydrogenase (isoforms) ; Eucalyptus ; Lignin ; XylemSource: Springer Online Journal Archives 1860-2000Topics: BiologyNotes: Abstract Two distinct isoforms of cinnamyl alcohol dehydrogenase, CAD 1 and CAD 2, have been purified to homogeneity from xylem-enriched fractions ofEucalyptus gunii Hook and partially characterized. They differ greatly in terms of both physical and biochemical properties, and can be separated by hydrophobic interaction chromatography on Phenyl Sepharose CL-4B. The native molecular weight of of CAD 1 is 38 kDa as determined by gel-filtration chromatography on Superose 6, and this isoform is likely to be a monomer since it yields a polypeptide of 35 kDa upon sodium dodecyl sulfatepolyacrylamide gel electrophoresis. It has a low substrate affinity for coniferyl andp-coumaryl alcohols and their corresponding aldehydes. No activity with sinapyl aldehyde and alcohol was detected. The more abundant isoform is CAD 2, which has a native molecular weight of 83 kDa and is a dinier composed of two subunits of slightly different molecular weights (42–43 kDa). These subunits show identical peptide patterns after digestion with N-chlorosuccinimide. The isoform, CAD 2, has a high substrate affinity for all the substrates tested. The two isoforms are immunologically distinct as polyclonal antibodies raised against CAD 2 do not cross-react with CAD 1. The characterization of two forms of CAD exhibiting such marked differences indicates their involvement in specific pathways of monolignol utilisation.Type of Medium: Electronic ResourceURL: -
10Articles: DFG German National LicensesStaff View
ISSN: 1573-5028Keywords: lignin ; CAD ; DNA sequence ; tobaccoSource: Springer Online Journal Archives 1860-2000Topics: BiologyNotes: Abstract Cinnamyl alcohol dehydrogenase (CAD, EC 1.1.1.195) is an enzyme involved in lignin biosynthesis. We have previously isolated pure CAD enzyme as two closely related polypeptides of 44 and 42.5 kDa from tobacco stems. In this paper, we report partial amino acid sequences of these two polypeptides. Based on the peptide sequences mixed oligonucleotides were used to screen a tobacco stem cDNA library and CAD cDNA clones encoding the two polypeptides were identified. DNA sequence comparisons indicate very high sequence identity between these clones both in the coding and in the 5′ and 3′ untranslated sequences. The close similarity between the two CAD genes leads us to suggest that they do not represent different isoforms but are the same gene from each of the two parental lines of Nicotiana tabacum cv. Samsun. Sequence comparisons with alcohol dehydrogenase 1 (ADH1) from yeast shows sequence similarities of ca. 30%, while comparisons with maize, barley and potato ADH1 sequences show similarities of not more than 23%.Type of Medium: Electronic ResourceURL: