ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    facet.materialart.
    Unknown
    Advanced Monte Carlo modeling of prompt fission neutrons for thermal and fast neutron-induced fission reactions on ^{239}Pu (2011)
    American Physical Society (APS)
    Details
    Publication Date: 2011-06-24
    Description: Author(s): P. Talou, B. Becker, T. Kawano, M. B. Chadwick, and Y. Danon Prompt fission neutrons following the thermal and 0.5 MeV neutron-induced fission reaction of 239 Pu are calculated using a Monte Carlo approach to the evaporation of the excited fission fragments. Exclusive data such as the multiplicity distribution P ( ν ) , the average multiplicity as a function of fr... [Phys. Rev. C 83, 064612] Published Thu Jun 23, 2011
    Keywords: Nuclear Reactions
    Print ISSN: 0556-2813
    Electronic ISSN: 1089-490X
    Topics: Physics
    Published by American Physical Society (APS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 2
    facet.materialart.
    Unknown
    Measurement and model analysis of (n,xα) cross sections for Cr, Fe, ^{59}Co, and ^{58,60}Ni from threshold energy to 150 MeV (2012)
    American Physical Society (APS)
    Details
    Publication Date: 2012-05-02
    Description: Author(s): S. Kunieda, R. C. Haight, T. Kawano, M. B. Chadwick, S. M. Sterbenz, F. B. Bateman, O. A. Wasson, S. M. Grimes, P. Maier-Komor, H. Vonach, T. Fukahori, and Y. Watanabe Neutron reactions that produce α particles have been investigated experimentally and analyzed by reaction model calculations for incident neutron energies from threshold to 150 MeV on elemental chromium and iron. The cross sections were measured at the Los Alamos Neutron Science Center by direct obs... [Phys. Rev. C 85, 054602] Published Tue May 01, 2012
    Keywords: Nuclear Reactions
    Print ISSN: 0556-2813
    Electronic ISSN: 1089-490X
    Topics: Physics
    Published by American Physical Society (APS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 3
    facet.materialart.
    Unknown
    Single cell activity reveals direct electron transfer in methanotrophic consortia (2015)
    Nature Publishing Group (NPG)
    Details
    Publication Date: 2015-09-17
    Description: Multicellular assemblages of microorganisms are ubiquitous in nature, and the proximity afforded by aggregation is thought to permit intercellular metabolic coupling that can accommodate otherwise unfavourable reactions. Consortia of methane-oxidizing archaea and sulphate-reducing bacteria are a well-known environmental example of microbial co-aggregation; however, the coupling mechanisms between these paired organisms is not well understood, despite the attention given them because of the global significance of anaerobic methane oxidation. Here we examined the influence of interspecies spatial positioning as it relates to biosynthetic activity within structurally diverse uncultured methane-oxidizing consortia by measuring stable isotope incorporation for individual archaeal and bacterial cells to constrain their potential metabolic interactions. In contrast to conventional models of syntrophy based on the passage of molecular intermediates, cellular activities were found to be independent of both species intermixing and distance between syntrophic partners within consortia. A generalized model of electric conductivity between co-associated archaea and bacteria best fit the empirical data. Combined with the detection of large multi-haem cytochromes in the genomes of methanotrophic archaea and the demonstration of redox-dependent staining of the matrix between cells in consortia, these results provide evidence for syntrophic coupling through direct electron transfer.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉McGlynn, Shawn E -- Chadwick, Grayson L -- Kempes, Christopher P -- Orphan, Victoria J -- England -- Nature. 2015 Oct 22;526(7574):531-5. doi: 10.1038/nature15512. Epub 2015 Sep 16.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, USA. ; Exobiology Branch, National Aeronautics and Space Administration Ames Research Center, Moffett Field, California 94035, USA. ; Control and Dynamical Systems, California Institute of Technology, Pasadena, California 91125, USA. ; SETI Institute, Mountain View, California 94034, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26375009" target="_blank"〉PubMed〈/a〉
    Keywords: Anaerobiosis ; Archaea/cytology/*metabolism ; Cytochromes/genetics/metabolism/ultrastructure ; Deltaproteobacteria/cytology/*metabolism ; Diffusion ; Electron Transport ; Genome, Archaeal/genetics ; Genome, Bacterial/genetics ; Heme/metabolism ; Methane/*metabolism ; Microbiota/physiology ; Models, Biological ; Molecular Sequence Data ; *Single-Cell Analysis ; Sulfates/metabolism ; *Symbiosis
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Published by Nature Publishing Group (NPG)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 4
    facet.materialart.
    Unknown
    Artificial electron acceptors decouple archaeal methane oxidation from sulfate reduction (2016)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2016-02-26
    Description: The oxidation of methane with sulfate is an important microbial metabolism in the global carbon cycle. In marine methane seeps, this process is mediated by consortia of anaerobic methanotrophic archaea (ANME) that live in syntrophy with sulfate-reducing bacteria (SRB). The underlying interdependencies within this uncultured symbiotic partnership are poorly understood. We used a combination of rate measurements and single-cell stable isotope probing to demonstrate that ANME in deep-sea sediments can be catabolically and anabolically decoupled from their syntrophic SRB partners using soluble artificial oxidants. The ANME still sustain high rates of methane oxidation in the absence of sulfate as the terminal oxidant, lending support to the hypothesis that interspecies extracellular electron transfer is the syntrophic mechanism for the anaerobic oxidation of methane.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Scheller, Silvan -- Yu, Hang -- Chadwick, Grayson L -- McGlynn, Shawn E -- Orphan, Victoria J -- New York, N.Y. -- Science. 2016 Feb 12;351(6274):703-7. doi: 10.1126/science.aad7154.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26912857" target="_blank"〉PubMed〈/a〉
    Keywords: Anaerobiosis ; *Carbon Cycle ; Electron Transport ; Geologic Sediments/microbiology ; Methane/*metabolism ; Methanosarcinales/classification/genetics/*metabolism ; Molecular Sequence Data ; Oxidation-Reduction ; Phylogeny ; RNA, Archaeal/classification/genetics ; Seawater/microbiology ; Sulfates/*metabolism ; Sulfur-Reducing Bacteria/metabolism
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 5
    facet.materialart.
    Unknown
    Late-time emission of prompt fission γ rays (2016)
    American Physical Society (APS)
    Details
    Publication Date: 2016-12-28
    Description: Author(s): P. Talou, T. Kawano, I. Stetcu, J. P. Lestone, E. McKigney, and M. B. Chadwick The emission of prompt fission γ rays within a few nanoseconds to a few microseconds following the scission point is studied in the Hauser-Feshbach formalism applied to the deexcitation of primary excited fission fragments. Neutron and γ -ray evaporations from fully accelerated fission fragments are … [Phys. Rev. C 94, 064613] Published Thu Dec 22, 2016
    Keywords: Nuclear Reactions
    Print ISSN: 0556-2813
    Electronic ISSN: 1089-490X
    Topics: Physics
    Published by American Physical Society (APS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 6
    Electronic Resource
    Electronic Resource
    Propylene polymerization with catalysts containing divalent titanium (1997)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2645-2652 
    Details
    ISSN: 0887-624X
    Keywords: propylene polymerization ; titanium oxidation state ; hydrogen activation ; catalyst decay ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The behavior in propylene polymerization of divalent titanium compounds of type [η6-areneTiAl2Cl8], both as such and supported on activated MgCl2, has been studied and compared to that of the simple catalyst MgCl2/TiCl4. Triethylaluminium was used as cocatalyst. The Ti-arene complexes were active both in the presence and in the absence of hydrogen, in contrast to earlier reports that divalent titanium species are active for ethylene but not for propylene polymerization. 13C-NMR analysis of low molecular weight polymer fractions indicated that the hydrogen activation effect observed for the MgCl2-supported catalysts should be ascribed to reactivation of 2,1-inserted (“dormant”) sites via chain transfer, rather than to (re)generation of active trivalent Ti via oxidative addition of hydrogen to divalent species. Decay in activity during polymerization was observed with both catalysts, indicating that for MgCl2/TiCl4 catalysts decay is not necessarily due to overreduction of Ti to the divalent state during polymerization. In ethylene polymerization both catalysts exhibited an acceleration rather than a decay profile. It is suggested that the observed decay in activity during propylene polymerization may be due to the formation of clustered species that are too hindered for propylene but that allow ethylene polymerization. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2645-2652, 1997
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
  • 7
    Electronic Resource
    Electronic Resource
    Application of conservation law to NMR measurements of poly(propylene) stereoregularity (1993)
    Basel : Wiley-Blackwell
    Die Makromolekulare Chemie, Theory and Simulations 2 (1993), S. 385-398 
    Details
    ISSN: 1018-5054
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A new method is presented for data reconciliation in the 13C NMR determination of the pentad distribution in regioregular poly(propylene). Deviations of experimentally measured data from mathematically derived conservation laws are corrected by a maximum-likelihood method. In this method some assumptions are made about the structure of the erros to obtain better estimates of the correct data. The validity of this procedure was demonstrated with Monte Carlo simulation, after which the method has been applied to real 13C NMR data to show what corrections may be obtained. Conservation laws for hexads and heptads are derived as well, for possible future use.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mats.1993.040020309
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Probabilistic multi-site modelling of propene polymerization using markov models (1993)
    Basel : Wiley-Blackwell
    Die Makromolekulare Chemie, Theory and Simulations 2 (1993), S. 399-420 
    Details
    ISSN: 1018-5054
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Possible propagation mechanisms in propene polymerization using heterogeneous catalysts are described by combinations of Bernoulli and first- or even second-order Markov models. Both NMR-measured pentad fractions and GPC Gel permeation chromatography.-measured molecular weight distributions are directly taken into account to fit an appropriate propagation model for a specific catalyst. The analytical data so obtained have been used for an examination of the applicability of multi-site propagation models and for estimation of the main parameters in each model. The propagation and termination probabilities are estimated, as are “mix” parameters giving the fraction of the polymer population stemming from each kind of propagation mechanism. In this way the subpopulation produced by each site is characterized in terms of tacticity and molecular weight distribution. A three-site model is required to explain the measured data properly.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mats.1993.040020310
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Effects of procatalyst composition on the stereospecificity of a Ziegler-Natta catalyst systemRevised manuscript of December 20, 1991. (1992)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 193 (1992), S. 1463-1468 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: In propylene polymerization with MgCl2/TiCl4/phthalate ester catalysts, using 2,2,6,6-tetramethylpiperidine as external donor, it has been found that the fraction of atactic polymer formed increased with decreasing ester content in the catalyst. At the same time, however, the stereoregularity of the isotactic polymer fraction, as measured by 13C NMR, increased. Polymerization in the absence of the external donor led to lower polymer yield and a lower stereoregularity of the isotactic fraction. The results indicate that the external donor is actively involved in the generation of isospecific sites, particularly in catalysts having relatively low ester contents.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1992.021930622
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Effect of polymerization temperature on the microtacticity of isotactic poly(propylene) prepared using heterogeneous (MgCl2-supported) Ziegler-Natta catalysts (1998)
    Weinheim : Wiley-Blackwell
    Macromolecular Chemistry and Physics 199 (1998), S. 1873-1878 
    Details
    ISSN: 1022-1352
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A study of the effect of polymerization temperature on the microtacticity of poly(propylene) prepared using various MgCl2-supported catalysts has shown that, in almost all cases, an increase in temperature leads not only to higher proportions of isotactic polymer but also to increased stereoregularity of the isotactic fraction. The results indicate a greater relative increase in productivity, with increasing temperature, for highly isospecific as opposed to moderately isospecific centres. It is suggested that easier propagation after the occasional regioirregular (2,1-) insertion may contribute to this effect.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...