Search Results - (Author, Cooperation:E. Jensen)

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  1. 1
    Staff View
    Publication Date:
    2018-06-16
    Publisher:
    MDPI Publishing
    Print ISSN:
    1661-7827
    Electronic ISSN:
    1660-4601
    Topics:
    Energy, Environment Protection, Nuclear Power Engineering
    Medicine
    Published by:
    http://www.mdpi.com/

    Latest Papers from Table of Contents or Articles in Press
  2. 2
    Staff View
    Publication Date:
    2018-03-06
    Publisher:
    BioMed Central
    Electronic ISSN:
    1472-698X
    Topics:
    Medicine
    Law
    Published by:
    http://www.biomedcentral.com/

    Latest Papers from Table of Contents or Articles in Press
  3. 3
    E. Jensen
    Nature Publishing Group (NPG)
    Published 2011
    Staff View
    Publication Date:
    2011-01-14
    Publisher:
    Nature Publishing Group (NPG)
    Print ISSN:
    0028-0836
    Electronic ISSN:
    1476-4687
    Topics:
    Biology
    Chemistry and Pharmacology
    Medicine
    Natural Sciences in General
    Physics
    Keywords:
    Administrative Personnel ; *Communication ; *Evaluation Studies as Topic ; *Public Opinion ; *Research Personnel/education
    Published by:
    http://www.nature.com/

    Latest Papers from Table of Contents or Articles in Press
  4. 4
    H. F. Zheng ; V. Forgetta ; Y. H. Hsu ; K. Estrada ; A. Rosello-Diez ; P. J. Leo ; C. L. Dahia ; K. H. Park-Min ; J. H. Tobias ; C. Kooperberg ; A. Kleinman ; U. Styrkarsdottir ; C. T. Liu ; C. Uggla ; D. S. Evans ; C. M. Nielson ; K. Walter ; U. Pettersson-Kymmer ; S. McCarthy ; J. Eriksson ; T. Kwan ; M. Jhamai ; K. Trajanoska ; Y. Memari ; J. Min ; J. Huang ; P. Danecek ; B. Wilmot ; R. Li ; W. C. Chou ; L. E. Mokry ; A. Moayyeri ; M. Claussnitzer ; C. H. Cheng ; W. Cheung ; C. Medina-Gomez ; B. Ge ; S. H. Chen ; K. Choi ; L. Oei ; J. Fraser ; R. Kraaij ; M. A. Hibbs ; C. L. Gregson ; D. Paquette ; A. Hofman ; C. Wibom ; G. J. Tranah ; M. Marshall ; B. B. Gardiner ; K. Cremin ; P. Auer ; L. Hsu ; S. Ring ; J. Y. Tung ; G. Thorleifsson ; A. W. Enneman ; N. M. van Schoor ; L. C. de Groot ; N. van der Velde ; B. Melin ; J. P. Kemp ; C. Christiansen ; A. Sayers ; Y. Zhou ; S. Calderari ; J. van Rooij ; C. Carlson ; U. Peters ; S. Berlivet ; J. Dostie ; A. G. Uitterlinden ; S. R. Williams ; C. Farber ; D. Grinberg ; A. Z. LaCroix ; J. Haessler ; D. I. Chasman ; F. Giulianini ; L. M. Rose ; P. M. Ridker ; J. A. Eisman ; T. V. Nguyen ; J. R. Center ; X. Nogues ; N. Garcia-Giralt ; L. L. Launer ; V. Gudnason ; D. Mellstrom ; L. Vandenput ; N. Amin ; C. M. van Duijn ; M. K. Karlsson ; O. Ljunggren ; O. Svensson ; G. Hallmans ; F. Rousseau ; S. Giroux ; J. Bussiere ; P. P. Arp ; F. Koromani ; R. L. Prince ; J. R. Lewis ; B. L. Langdahl ; A. P. Hermann ; J. E. Jensen ; S. Kaptoge ; K. T. Khaw ; J. Reeve ; M. M. Formosa ; A. Xuereb-Anastasi ; K. Akesson ; F. E. McGuigan ; G. Garg ; J. M. Olmos ; M. T. Zarrabeitia ; J. A. Riancho ; S. H. Ralston ; N. Alonso ; X. Jiang ; D. Goltzman ; T. Pastinen ; E. Grundberg ; D. Gauguier ; E. S. Orwoll ; D. Karasik ; G. Davey-Smith ; A. V. Smith ; K. Siggeirsdottir ; T. B. Harris ; M. C. Zillikens ; J. B. van Meurs ; U. Thorsteinsdottir ; M. T. Maurano ; N. J. Timpson ; N. Soranzo ; R. Durbin ; S. G. Wilson ; E. E. Ntzani ; M. A. Brown ; K. Stefansson ; D. A. Hinds ; T. Spector ; L. A. Cupples ; C. Ohlsson ; C. M. Greenwood ; R. D. Jackson ; D. W. Rowe ; C. A. Loomis ; D. M. Evans ; C. L. Ackert-Bicknell ; A. L. Joyner ; E. L. Duncan ; D. P. Kiel ; F. Rivadeneira ; J. B. Richards
    Nature Publishing Group (NPG)
    Published 2015
    Staff View
    Publication Date:
    2015-09-15
    Publisher:
    Nature Publishing Group (NPG)
    Print ISSN:
    0028-0836
    Electronic ISSN:
    1476-4687
    Topics:
    Biology
    Chemistry and Pharmacology
    Medicine
    Natural Sciences in General
    Physics
    Keywords:
    Animals ; Bone Density/*genetics ; Bone and Bones/metabolism ; Disease Models, Animal ; Europe/ethnology ; European Continental Ancestry Group/genetics ; Exome/genetics ; Female ; Fractures, Bone/*genetics ; Gene Frequency/genetics ; Genetic Predisposition to Disease/genetics ; Genetic Variation/genetics ; Genome, Human/*genetics ; Genomics ; Genotype ; Homeodomain Proteins/*genetics ; Humans ; Mice ; Sequence Analysis, DNA ; Wnt Proteins/genetics
    Published by:
    http://www.nature.com/

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  5. 5
    Staff View
    Publication Date:
    2018-05-23
    Publisher:
    American Physical Society (APS)
    Print ISSN:
    1539-3755
    Electronic ISSN:
    1550-2376
    Topics:
    Physics
    Keywords:
    Biological Physics
    Published by:
    http://www.aps.org/

    Latest Papers from Table of Contents or Articles in Press
  6. 6
    C. R. Webster ; P. R. Mahaffy ; G. J. Flesch ; P. B. Niles ; J. H. Jones ; L. A. Leshin ; S. K. Atreya ; J. C. Stern ; L. E. Christensen ; T. Owen ; H. Franz ; R. O. Pepin ; A. Steele ; C. Achilles ; C. Agard ; J. A. Alves Verdasca ; R. Anderson ; D. Archer ; C. Armiens-Aparicio ; R. Arvidson ; E. Atlaskin ; A. Aubrey ; B. Baker ; M. Baker ; T. Balic-Zunic ; D. Baratoux ; J. Baroukh ; B. Barraclough ; K. Bean ; L. Beegle ; A. Behar ; J. Bell ; S. Bender ; M. Benna ; J. Bentz ; G. Berger ; J. Berger ; D. Berman ; D. Bish ; D. F. Blake ; J. J. Blanco Avalos ; D. Blaney ; J. Blank ; H. Blau ; L. Bleacher ; E. Boehm ; O. Botta ; S. Bottcher ; T. Boucher ; H. Bower ; N. Boyd ; B. Boynton ; E. Breves ; J. Bridges ; N. Bridges ; W. Brinckerhoff ; D. Brinza ; T. Bristow ; C. Brunet ; A. Brunner ; W. Brunner ; A. Buch ; M. Bullock ; S. Burmeister ; M. Cabane ; F. Calef ; J. Cameron ; J. Campbell ; B. Cantor ; M. Caplinger ; J. Caride Rodriguez ; M. Carmosino ; I. Carrasco Blazquez ; A. Charpentier ; S. Chipera ; D. Choi ; B. Clark ; S. Clegg ; T. Cleghorn ; E. Cloutis ; G. Cody ; P. Coll ; P. Conrad ; D. Coscia ; A. Cousin ; D. Cremers ; J. Crisp ; A. Cros ; F. Cucinotta ; C. d'Uston ; S. Davis ; M. Day ; M. de la Torre Juarez ; L. DeFlores ; D. DeLapp ; J. DeMarines ; D. DesMarais ; W. Dietrich ; R. Dingler ; C. Donny ; B. Downs ; D. Drake ; G. Dromart ; A. Dupont ; B. Duston ; J. Dworkin ; M. D. Dyar ; L. Edgar ; K. Edgett ; C. Edwards ; L. Edwards ; B. Ehlmann ; B. Ehresmann ; J. Eigenbrode ; B. Elliott ; H. Elliott ; R. Ewing ; C. Fabre ; A. Fairen ; K. Farley ; J. Farmer ; C. Fassett ; L. Favot ; D. Fay ; F. Fedosov ; J. Feldman ; S. Feldman ; M. Fisk ; M. Fitzgibbon ; M. Floyd ; L. Fluckiger ; O. Forni ; A. Fraeman ; R. Francis ; P. Francois ; C. Freissinet ; K. L. French ; J. Frydenvang ; A. Gaboriaud ; M. Gailhanou ; J. Garvin ; O. Gasnault ; C. Geffroy ; R. Gellert ; M. Genzer ; D. Glavin ; A. Godber ; F. Goesmann ; W. Goetz ; D. Golovin ; F. Gomez Gomez ; J. Gomez-Elvira ; B. Gondet ; S. Gordon ; S. Gorevan ; J. Grant ; J. Griffes ; D. Grinspoon ; J. Grotzinger ; P. Guillemot ; J. Guo ; S. Gupta ; S. Guzewich ; R. Haberle ; D. Halleaux ; B. Hallet ; V. Hamilton ; C. Hardgrove ; D. Harker ; D. Harpold ; A. M. Harri ; K. Harshman ; D. Hassler ; H. Haukka ; A. Hayes ; K. Herkenhoff ; P. Herrera ; S. Hettrich ; E. Heydari ; V. Hipkin ; T. Hoehler ; J. Hollingsworth ; J. Hudgins ; W. Huntress ; J. Hurowitz ; S. Hviid ; K. Iagnemma ; S. Indyk ; G. Israel ; R. Jackson ; S. Jacob ; B. Jakosky ; E. Jensen ; J. K. Jensen ; J. Johnson ; M. Johnson ; S. Johnstone ; A. Jones ; J. Joseph ; I. Jun ; L. Kah ; H. Kahanpaa ; M. Kahre ; N. Karpushkina ; W. Kasprzak ; J. Kauhanen ; L. Keely ; O. Kemppinen ; D. Keymeulen ; M. H. Kim ; K. Kinch ; P. King ; L. Kirkland ; G. Kocurek ; A. Koefoed ; J. Kohler ; O. Kortmann ; A. Kozyrev ; J. Krezoski ; D. Krysak ; R. Kuzmin ; J. L. Lacour ; V. Lafaille ; Y. Langevin ; N. Lanza ; J. Lasue ; S. Le Mouelic ; E. M. Lee ; Q. M. Lee ; D. Lees ; M. Lefavor ; M. Lemmon ; A. Lepinette Malvitte ; R. Leveille ; E. Lewin-Carpintier ; K. Lewis ; S. Li ; L. Lipkaman ; C. Little ; M. Litvak ; E. Lorigny ; G. Lugmair ; A. Lundberg ; E. Lyness ; M. Madsen ; J. Maki ; A. Malakhov ; C. Malespin ; M. Malin ; N. Mangold ; G. Manhes ; H. Manning ; G. Marchand ; M. Marin Jimenez ; C. Martin Garcia ; D. Martin ; M. Martin ; J. Martinez-Frias ; J. Martin-Soler ; F. J. Martin-Torres ; P. Mauchien ; S. Maurice ; A. McAdam ; E. McCartney ; T. McConnochie ; E. McCullough ; I. McEwan ; C. McKay ; S. McLennan ; S. McNair ; N. Melikechi ; P. Y. Meslin ; M. Meyer ; A. Mezzacappa ; H. Miller ; K. Miller ; R. Milliken ; D. Ming ; M. Minitti ; M. Mischna ; I. Mitrofanov ; J. Moersch ; M. Mokrousov ; A. Molina Jurado ; J. Moores ; L. Mora-Sotomayor ; J. M. Morookian ; R. Morris ; S. Morrison ; R. Mueller-Mellin ; J. P. Muller ; G. Munoz Caro ; M. Nachon ; S. Navarro Lopez ; R. Navarro-Gonzalez ; K. Nealson ; A. Nefian ; T. Nelson ; M. Newcombe ; C. Newman ; H. Newsom ; S. Nikiforov ; B. Nixon ; E. Noe Dobrea ; T. Nolan ; D. Oehler ; A. Ollila ; T. Olson ; M. A. de Pablo Hernandez ; A. Paillet ; E. Pallier ; M. Palucis ; T. Parker ; Y. Parot ; K. Patel ; M. Paton ; G. Paulsen ; A. Pavlov ; B. Pavri ; V. Peinado-Gonzalez ; L. Peret ; R. Perez ; G. Perrett ; J. Peterson ; C. Pilorget ; P. Pinet ; J. Pla-Garcia ; I. Plante ; F. Poitrasson ; J. Polkko ; R. Popa ; L. Posiolova ; A. Posner ; I. Pradler ; B. Prats ; V. Prokhorov ; S. W. Purdy ; E. Raaen ; L. Radziemski ; S. Rafkin ; M. Ramos ; E. Rampe ; F. Raulin ; M. Ravine ; G. Reitz ; N. Renno ; M. Rice ; M. Richardson ; F. Robert ; K. Robertson ; J. A. Rodriguez Manfredi ; J. J. Romeral-Planello ; S. Rowland ; D. Rubin ; M. Saccoccio ; A. Salamon ; J. Sandoval ; A. Sanin ; S. A. Sans Fuentes ; L. Saper ; P. Sarrazin ; V. Sautter ; H. Savijarvi ; J. Schieber ; M. Schmidt ; W. Schmidt ; D. Scholes ; M. Schoppers ; S. Schroder ; S. Schwenzer ; E. Sebastian Martinez ; A. Sengstacken ; R. Shterts ; K. Siebach ; T. Siili ; J. Simmonds ; J. B. Sirven ; S. Slavney ; R. Sletten ; M. Smith ; P. Sobron Sanchez ; N. Spanovich ; J. Spray ; S. Squyres ; K. Stack ; F. Stalport ; T. Stein ; N. Stewart ; S. L. Stipp ; K. Stoiber ; E. Stolper ; B. Sucharski ; R. Sullivan ; R. Summons ; D. Sumner ; V. Sun ; K. Supulver ; B. Sutter ; C. Szopa ; F. Tan ; C. Tate ; S. Teinturier ; I. ten Kate ; P. Thomas ; L. Thompson ; R. Tokar ; M. Toplis ; J. Torres Redondo ; M. Trainer ; A. Treiman ; V. Tretyakov ; R. Urqui-O'Callaghan ; J. Van Beek ; T. Van Beek ; S. VanBommel ; D. Vaniman ; A. Varenikov ; A. Vasavada ; P. Vasconcelos ; E. Vicenzi ; A. Vostrukhin ; M. Voytek ; M. Wadhwa ; J. Ward ; E. Weigle ; D. Wellington ; F. Westall ; R. C. Wiens ; M. B. Wilhelm ; A. Williams ; J. Williams ; R. Williams ; R. B. Williams ; M. Wilson ; R. Wimmer-Schweingruber ; M. Wolff ; M. Wong ; J. Wray ; M. Wu ; C. Yana ; A. Yen ; A. Yingst ; C. Zeitlin ; R. Zimdar ; M. P. Zorzano Mier
    American Association for the Advancement of Science (AAAS)
    Published 2013
    Staff View
    Publication Date:
    2013-07-23
    Publisher:
    American Association for the Advancement of Science (AAAS)
    Print ISSN:
    0036-8075
    Electronic ISSN:
    1095-9203
    Topics:
    Biology
    Chemistry and Pharmacology
    Computer Science
    Medicine
    Natural Sciences in General
    Physics
    Published by:
    http://www.aaas.org/

    Latest Papers from Table of Contents or Articles in Press
  7. 7
    A. Moss ; E. Jensen ; M. Gusset
    Nature Publishing Group (NPG)
    Published 2014
    Staff View
    Publication Date:
    2014-04-11
    Publisher:
    Nature Publishing Group (NPG)
    Print ISSN:
    0028-0836
    Electronic ISSN:
    1476-4687
    Topics:
    Biology
    Chemistry and Pharmacology
    Medicine
    Natural Sciences in General
    Physics
    Keywords:
    Animals ; *Animals, Zoo ; *Biodiversity ; Conservation of Natural Resources/*trends ; Ecology/*education
    Published by:
    http://www.nature.com/

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  8. 8
    Staff View
    Publication Date:
    2018-01-10
    Publisher:
    BMJ Publishing Group
    Print ISSN:
    0017-5749
    Electronic ISSN:
    1468-3288
    Topics:
    Medicine
    Published by:
    http://www.bmj.com/

    Latest Papers from Table of Contents or Articles in Press
  9. 9
    Staff View
    Publication Date:
    2018-10-09
    Publisher:
    American Chemical Society (ACS)
    Print ISSN:
    0002-7863
    Electronic ISSN:
    1520-5126
    Topics:
    Chemistry and Pharmacology
    Published by:
    http://www.acs.org/

    Latest Papers from Table of Contents or Articles in Press
  10. 10
    Lao, K. Q. ; Jensen, E. ; Kash, P. W. ; Butler, L. J.

    College Park, Md. : American Institute of Physics (AIP)
    Published 1990
    Staff View
    ISSN:
    1089-7690
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Chemistry and Pharmacology
    Notes:
    We report the polarized emission spectra from photodissociating nitromethane excited at 200 and 218 nm. At both excitation wavelengths, the emission spectra show a strong progression in the NO2 symmetric stretch; at 200 nm a weak progression in the NO2 symmetric stretch in combination with one quantum in the C–N stretch also contributes to the spectra. We measure the angular distribution of emitted photons in the strong emission features from the relative intensity ratio between photons detected perpendicular to versus along the direction of the electric vector of the excitation laser. We find the anisotropy is substantially reduced from the 2:1 ratio expected for the pure CH3NO2 X(1A1)→1B2(ππ*)→X(1A1) transition with no rotation of the molecular frame. The intensity ratios for the features in the NO2 symmetric stretching progression lie near 1.5 to 1.6 for 200 nm excitation and 1.7 for 218 nm excitation. The analysis of the photon angular distribution measurements and consideration of the absorption spectrum indicate that the timescale of the dissociation is too fast for molecular rotation to contribute significantly to the observed reduction in anisotropy. The detailed analysis of our results in conjunction with electron correlation arguments and previous work on the absorption spectroscopy and final products' velocities results in a model which includes two dissociation pathways for nitromethane, an electronic predissociation pathway and a vibrational predissociation pathway along the 1B2(ππ*) surface. Our analysis suggests a reassignment of the minor dissociation channel, first evidenced in photofragment velocity analysis experiments which detected a pathway producing slow CH3 fragments, to the near threshold dissociation channel CH3 + NO2(2 2B2).
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.458781

    Articles: DFG German National Licenses
  11. 11
    Keller, J. S. ; Kash, P. W. ; Jensen, E. ; Butler, L. J.

    College Park, Md. : American Institute of Physics (AIP)
    Published 1992
    Staff View
    ISSN:
    1089-7690
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Chemistry and Pharmacology
    Notes:
    We investigate the origin of the observed fission of the stronger S–H bond over the weaker C–S bond in CH3SH excited at 193 nm using the complementary techniques of mass-resolved photofragment time-of-flight spectroscopy and emission spectroscopy. The velocities and angular distributions of the CH3S and SH photofragments show that both C–S and S–H bond fission occur on a subpicosecond timescale and impart considerable energy to relative product translation. The dispersed emission from photoexcited CH3SH molecules in a flow cell evidences a progression in the CH3 umbrella mode and combination bands with one quantum in the C–S stretch, but no progression with S–H stretch. Examination of the results with reference to previous ab initio calculations of the excited state surfaces reveals the importance of nonadiabatic coupling in the dissociation dynamics. This is a clear example of selective bond fission upon excitation of an electronic state that is not repulsive in the bond that breaks. We discuss the implication of the work with respect to using the Born–Oppenheimer approximation in reactive collisions near a saddle point along the reaction coordinate.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.462825

    Articles: DFG German National Licenses
  12. 12
    Dixon-Warren, St. J. ; Heyd, D. V. ; Jensen, E. T. ; Polanyi, J. C.

    College Park, Md. : American Institute of Physics (AIP)
    Published 1993
    Staff View
    ISSN:
    1089-7690
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Chemistry and Pharmacology
    Notes:
    A photoinduced ion–molecule reaction is reported between superimposed molecular layers of alkyl halides on a metal substrate CH3X/RCl/Ag(111) (where X=Br or I and R=CCl3, CHCl2, or CH2Cl) to form CH3Cl(ad) (wavelengths 193, 248, and 350 nm). The reaction is mediated by charge-transfer (CT) photodissociation, in which photoelectrons from the metal surface transfer to the lower layer of adsorbate RCl to form RCl−. These negative ions then react with the upper layer CH3X in an ion–molecule reaction to form CH3Cl+X−. The yield of product CH3Cl is found to be enhanced at ∼1 ML of adsorbed CH3X (upper layer) due to a decrease in the local potential in the region of the adsorbate–adsorbate interface that enhances the probability of CT to the lower layer. In addition to lowering the local potential at the interface, the adsorbed CH3X also lowers the surface work function; as a result changes in the microscopic local potential correlate (via the CT reaction rate) with changes in the observed macroscopic work function. The yield of CH3Cl decreases at still higher CH3X coverage in the upper layer as the work function increases. The ion–molecule reaction gives evidence of being a concerted process in which the Cl− reacts as it separates from RCl− rather than following separation. The reagent RCl−, as in the surface reaction discussed in the previous paper, is formed by CT from "hot'' electrons rather than free photoelectrons.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.464889

    Articles: DFG German National Licenses
  13. 13
    Jensen, E. ; Keller, J. S. ; Waschewsky, G. C. G. ; Stevens, J. E. ; Graham, R. L. ; Freed, K. F. ; Butler, L. J.

    College Park, Md. : American Institute of Physics (AIP)
    Published 1993
    Staff View
    ISSN:
    1089-7690
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Chemistry and Pharmacology
    Notes:
    These experiments use molecular photodissociation of CH3SH to probe the dynamics and the influence of nonadiabatic coupling in the transition state region of the CH3+SH→CH3S+H reaction. Photoexcitation at 222 and 248 nm in the first of two absorption bands accesses the lower of the two coupled potential energy surfaces near the saddle point of the excited state reaction coordinate. Measurement of the resulting photofragments' velocities and angular distributions determine the branching between the CH3+SH and the CH3S+H exit channels. At all wavelengths within the first absorption band, we observe preferential fission of the stronger S–H bond over the weaker C–S bond. Fission of the C–S bond occurs only to a small degree at 222 nm and is not observable at 248 nm. Comparison with our earlier data at 193 nm, corresponding to excitation to the upper bound adiabat which is nonadiabatically coupled to the lower dissociative surface reached at 222 nm, shows that the branching ratio between C–S bond fission and S–H bond fission is a factor of eight larger at 193 nm.To probe the forces in the Franck–Condon region, we also measure the photoemission spectrum from dissociating CH3SH excited at 222 nm and compare it to the previous measurement at 193 nm. The 222 nm spectrum evidences emission into the S–H stretch and methyl stretch vibrations but not into C–S stretching modes, consistent with the dominance of S–H fission on the lower adiabat, while the 193 nm emission spectrum, reassigned here, has only a progression in the C–S stretch. The comparison of the spectra suggests a model in which stretching along the C–S coordinate on the bound upper state occurs as the amplitude couples nonadiabatically to the lower dissociative surface, allowing the molecule to access the region near the saddle point on the lower surface at extended C–S bond lengths. This results in better overlap with the C–S fission exit channel and thus an increased branching to C–S bond fission over that observed upon direct excitation to the lower dissociative surface at 222 nm. To further advance the experimental conclusions, we present collaborative calculations of the potential energy surfaces using the effective valence-shell Hamiltonian method developed by Freed and co-workers.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.464116

    Articles: DFG German National Licenses
  14. 14
    Dixon-Warren, St. J. ; Jensen, E. T. ; Polanyi, J. C.

    College Park, Md. : American Institute of Physics (AIP)
    Published 1993
    Staff View
    ISSN:
    1089-7690
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Chemistry and Pharmacology
    Notes:
    Photoinduced charge-transfer (CT) dissociation of adsorbates is reported in this paper for a series of chloromethanes (RCl) adsorbed on Ag(111). The chloromethanes were CCl4, CHCl3, CH2Cl2, CH3Cl, and CCl3Br. The observation that Cl− ions were emitted following UV laser irradiation of the chloromethane covered metal surface gave direct evidence for CT photodissociation RCl/Ag(111)+hν→(RCl−)
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.464888

    Articles: DFG German National Licenses
  15. 15
    Jensen, E. ; Bartynski, R. A. ; Hulbert, S. L. ; Johnson, E. D.

    [S.l.] : American Institute of Physics (AIP)
    Published 1992
    Staff View
    ISSN:
    1089-7623
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Electrical Engineering, Measurement and Control Technology
    Notes:
    The technique of Auger photoelectron coincidence spectroscopy (APECS) using synchrotron radiation is discussed. Technical considerations and experimental details are emphasized. Results from Cu(100), Ta(100), and Al(111) are presented to show the kinds of new information that APECS can provide.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.1142602

    Articles: DFG German National Licenses
  16. 16
    Connell, L. L. ; Fleming, J. W. ; Chu, H.-N. ; Vestyck, D. J. ; Jensen, E. ; Butler, J. E.

    [S.l.] : American Institute of Physics (AIP)
    Published 1995
    Staff View
    ISSN:
    1089-7550
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Notes:
    We report here a direct measurement of the spatially resolved atomic hydrogen concentration profiles during hot-filament-assisted chemical-vapor deposition (HFCVD) of diamond films. The ground-state hydrogen (1s 2S1/2) atoms generated in this process are monitored by an optical four-wave-mixing technique, third-harmonic generation (THG). For THG, a 364.6 nm dye laser beam is focused into the HFCVD reactor and the third-harmonic radiation near resonant with the Lyman-α (2p 2P0j↔1s 2S1/2) transition in atomic hydrogen at 121.6 nm is observed. The resultant THG intensity and THG peak shift with respect to the Lyman-α transition are both dependent on hydrogen atom concentration. Titration experiments based on the reaction NOCl+H→HCl+NO were conducted to obtain absolute hydrogen atom concentrations from the relative concentrations determined in the THG experiment. Spatially resolved molecular hydrogen temperature and concentration profiles obtained by coherent anti-Stokes Raman scattering in a similar HFCVD reactor are reported. The observed H atom concentrations exceed computed equilibrium concentrations based on the measured gas temperatures. Transport of the atomic hydrogen from the hot filament surfaces is discussed and diffusion is shown to be the principal mechanism controlling the H atom distribution.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.359939

    Articles: DFG German National Licenses
  17. 17
    Jensen, E. T. ; Palmer, R. E.

    [S.l.] : American Institute of Physics (AIP)
    Published 1989
    Staff View
    ISSN:
    1089-7623
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Electrical Engineering, Measurement and Control Technology
    Notes:
    A high-sensitivity low-energy electron diffraction (LEED) system based on an electron energy loss spectrometer is described. This instrument is found to have the advantages of good angular resolution, very good energy resolution, low target current and high dynamic range. The experimental control and data collection are automated, which is found to be necessary to reduce measurement times to practicable levels. The performance of the system is illustrated by LEED data obained for a submonolayer of C6H6 physisorbed on graphite at 35 K where a weak diffraction feature is observed for the first time.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.1140605

    Articles: DFG German National Licenses
  18. 18
    Stetson, C. A. ; Jensen, E.

    Oxford, UK : Blackwell Publishing Ltd
    Published 1960
    Staff View
    ISSN:
    1749-6632
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Natural Sciences in General
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1111/j.1749-6632.1960.tb23198.x

    Articles: DFG German National Licenses
  19. 19
    Heyd, D. V. ; Jensen, E. T. ; Polanyi, J. C.

    College Park, Md. : American Institute of Physics (AIP)
    Published 1995
    Staff View
    ISSN:
    1089-7690
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Chemistry and Pharmacology
    Notes:
    At (approximately-greater-than)1 ML coverage of methyl bromide adsorbed on LiF(100), CH3Br is efficiently "photoejected'' by ultraviolet light at 193 nm, with a mean translational energy of ∼0.3 eV; this is termed PEJ(CH3Br). The system CH3Cl/LiF(100) shows no detectable PEJ(CH3Cl) at this wavelength for which CH3Cl does not efficiently absorb UV. Similarly PEJ(CH3Br) ceased to be observable with 248 nm light, at which wavelength CH3Br does not absorb. Both observations indicate that PEJ is adsorbate mediated. If at 193 nm ∼1 ML of CH3Br is adsorbed beneath ∼1 ML of CH3Cl, efficient PEJ(CH3Cl) is observed. With the sequence of layers reversed (i.e., with the actinic layer on top), PEJ(CH3Cl) is largely suppressed. These observations support the model for PEJ proposed previously [I. Harrison et al., J. Chem. Phys. 89, 1498 (1988)] in which photoexcitation of the underlayer leads, by way of electronic-to-translational (E→T) transfer, to ejection of the top layer. The angular distribution of the photoejected species is peaked along the surface normal, consistent with repulsion operating between the under- and overlayer. The mean conversion of E→T implied by this mechanism is ∼5%, extending to a maximum of 12%. © 1995 American Institute of Physics.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.469611

    Articles: DFG German National Licenses
  20. 20
    Browning, P. W. ; Jensen, E. ; Waschewsky, G. C. G. ; Tate, M. R. ; Butler, L. J. ; Hessler, J. P.

    College Park, Md. : American Institute of Physics (AIP)
    Published 1994
    Staff View
    ISSN:
    1089-7690
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Chemistry and Pharmacology
    Notes:
    This study uses emission spectroscopy of H2S at excitation energies near 200 nm to probe the dissociation dynamics from a conical intersection in the Franck–Condon region to the H+SH product exit channel. Photoexcitation accesses these coupled surfaces near the transition state region of the lower adiabat, a potential surface for the excited state H+SH→HS+H reaction. Excitation wavelengths from 199–203 nm tune through the first of the resonances in the absorption spectrum assigned to recurrences in the motion along the symmetric stretch orthogonal to the reaction coordinate and also access energies just above and at the conical intersection. We disperse the emission from the dissociating molecules at each of five excitation wavelengths in this region to probe several features of the reaction dynamics on the coupled potential energy surfaces. The resulting emission spectra cover the range of final vibrational eigenstates from 500 to 11 000 cm−1 above the initial ground vibrational state for all five excitation wavelengths, and go out to 16 500 cm−1 for the 199 and 201 nm excitation wavelengths. The resulting spectra, when considered in conjunction with recent scattering calculations by Heumann and Schinke on ab initio potential energy surfaces for this system, evidence a progression of emission features to low vibrational eigenstates in the SH stretch that result from coupling of the nuclear motion from the bound to the dissociative region of the potential energy surfaces.This emission, into local mode eigenstates such as 00+1, 11+0, 11+1, 21+0, 21+1, evidences the antisymmetric dissociative motion and bending induced near the conical intersection, and dominates the spectrum at excitation wavelengths only near 200 nm. We analyze the excitation wavelength dependence of these features and also of the n0+0 progression for n≥4, which reflect the exit channel dynamics. The excitation wavelength dependence shows that while the emission spectra do not reveal any dynamics unique to scattering states that access a symmetric stretch resonance in the Franck–Condon region, they do reveal the energy location of and the dynamics at the conical intersection. A reanalysis of other workers' measurements of the SH product vibrational state distribution shows that v=0 products are strongly favored at excitation wavelengths near the conical intersection.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.467351

    Articles: DFG German National Licenses