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CHIRONOMID FAUNA OF CENTRAL YAKUTIAN LAKES (NORTHERN RUSSIA) IN PALAEOENVIRONMENTAL INVESTIGATION
L Nazarova,T. Kumke,L Pestrjakova,H.-W. Hubberten
Chironomus Newsletter on Chironomidae Research , 2009,
Abstract: --
CHIRONOMID FAUNA OF CENTRAL YAKUTIAN LAKES (NORTHERN RUSSIA) IN PALAEOENVIRONMENTAL INVESTIGATION
L. Nazarova,T. Kumke,L. Pestrjakova,H.-W. Hubberten
Chironomus Newsletter on Chironomidae Research , 2009,
Abstract: --
A 250 ka oxygen isotope record from diatoms at Lake El'gygytgyn, far east Russian Arctic
B. Chapligin, H. Meyer, G. E. A. Swann, C. Meyer-Jacob,H.-W. Hubberten
Climate of the Past (CP) & Discussions (CPD) , 2012,
Abstract: In 2003 sediment core Lz1024 was drilled at Lake El'gygytgyn, far east Russian Arctic, in an area of the Northern Hemisphere which has not been glaciated for the last 3.6 Ma. Biogenic silica was used for analysing the oxygen isotope composition (δ18Odiatom) in the upper 13 m long section dating back about 250 ka with samples dominated by one taxa in the <10 μm fraction (Cyclotella ocellata). Downcore variations in δ18O values show that glacial-interglacial cycles are present throughout the core and δ18Odiatom-values are mainly controlled by δ18Oprecipitation. Changes reflect the Holocene Thermal Maximum, the Last Glacial Maximum (LGM) and the interglacial periods corresponding to MIS 5.5 and MIS 7 with a peak-to-peak amplitude between LGM and MIS 5.5 of Δ18O = 5.3‰. This corresponds to a mean annual air temperature difference of about 9 °C. Our record is the first continuous δ18Odiatom record from an Arctic lake sediment core directly responding to precipitation and dating back more than 250 ka and correlates well with the stacked marine δ18O LR04 (r = 0.58) and δD EPICA Dome-C record (r = 0.69). With δ18O results indicating strong links to both marine and ice-core records, records from Lake El'gygytgyn can be used to further investigate the sensitivity of the Arctic climate to both past and future global climatic changes.
A 250 ka oxygen isotope record from diatoms at Lake El'gygytgyn, far east Russian Arctic
Chapligin, B.,Hubberten, H.-W.,Meyer, H.,Meyer-Jacob, C.,Swann, G. E. A.
- , 2012, DOI: https://doi.org/10.5194/cp-8-1621-2012
Abstract:

Abstract. In 2003 sediment core Lz1024 was drilled at Lake El'gygytgyn, far east Russian Arctic, in an area of the Northern Hemisphere which has not been glaciated for the last 3.6 Ma. Biogenic silica was used for analysing the oxygen isotope composition (δ18Odiatom) in the upper 13 m long section dating back about 250 ka with samples dominated by one taxa in the <10 μm fraction (Cyclotella ocellata). Downcore variations in δ18O values show that glacial-interglacial cycles are present throughout the core and δ18Odiatom-values are mainly controlled by δ18Oprecipitation. Changes reflect the Holocene Thermal Maximum, the Last Glacial Maximum (LGM) and the interglacial periods corresponding to MIS 5.5 and MIS 7 with a peak-to-peak amplitude between LGM and MIS 5.5 of Δ18O = 5.3‰. This corresponds to a mean annual air temperature difference of about 9 °C. Our record is the first continuous δ18Odiatom record from an Arctic lake sediment core directly responding to precipitation and dating back more than 250 ka and correlates well with the stacked marine δ18O LR04 (r = 0.58) and δD EPICA Dome-C record (r = 0.69). With δ18O results indicating strong links to both marine and ice-core records, records from Lake El'gygytgyn can be used to further investigate the sensitivity of the Arctic climate to both past and future global climatic changes.

Sedimentation conditions and rock-magnetic properties of Quaternary deposits from Laguna de Santa Rosa, Iturbide region, northeastern Mexico
J. Urrutia-Fucugauchi,M.A. Ruiz-Martínez,J. Werner,H.-W. Hubberten
Geofísica internacional , 2003,
Abstract: We report initial results of an interdisciplinary study of the lacustrine sequence of Laguna de Santa Rosa, based on a 26 m long core recovered from its northern-central sector. The Laguna is an intramontane elongated basin with a small catchment area at an altitude of 1520 m asl in the central sector of the Sierra Madre Oriental in the Iturbide region, northeastern Mexico. The stratigraphic variations of rock-magnetic properties, total carbonate content and isotopic carbon, and mineralogy define three major zones separated by peaks of the calcite to quartz+phyllosilicate+feldspar ratio. The upper zone, from surface to 7-9 m, is formed by an organic clay with abundant gasteropods and two black to green clays. It is characterized by magnetic susceptibility around 10-6 SI, frequency dependent factor of 0 %, δ13 C ranging from –20.3 ‰ at surface to –26.4 ‰, presence of quartz and phyllosilicates with generally more than 20 % calcite, and sporadic occurrence of plagioclase (albite) with K-feldspars nearly absent. The middle zone, from 9 m to 17.5 m, is formed by five clay units with colors ranging from green gray to brown. This zone is characterized by variable susceptibility up to 17 10-6 SI, negative frequency dependent factors, low total carbon content, quartz and phyllosilicate enrichment, less calcite and presence of K-feldspars. This middle zone shows higher detrital input and/or reduced productivity, which suggests a cold and less humid interval. The lower zone extends from 17.5 m to 26 m and shows two brown to green gray clay units. This zone is characterized by magnetic susceptibility between 8 10-6 SI and 14 10-6 SI, variable frequency dependent factors, and δ13 C values around –24 ‰. Its mineralogy is similar to the upper zone, again enriched in calcite and occurrence of plagioclase. The phyllosilicate fraction is mainly composed of mica, chlorite, smectite and kaolinite. The magnetic minerals are allogenic, derived from the lutites that form the catchment basin.
Sensationssuchende Narzissten, Extraversion und Selbstdarstellung in sozialen Netzwerken im Web 2.0
Brailovskaia, J.,Bierhoff, H.-W.
Journal of Business and Media Psychology , 2012,
Abstract: Das Ziel der vorliegenden Arbeit bestand darin, die Beziehung zwischen den Pers nlichkeitsmerkmalen offener und verdeckter Narzissmus, Sensation Seeking sowie Extraversion und der Selbstdarstellung auf einer sozialen Netzwerkseite im Web 2.0 (hier: www.studiVZ.net) zu untersuchen. Es sollte geprüft werden, ob Sensation Seeking einen Einfluss auf den Zusammenhang zwischen dem Narzissmus und der virtuellen Selbstdarstellung nimmt. Zus tzlich wurde untersucht, ob sich die vier Pers nlichkeitsmerkmale in der Art der sozialen Online-Interaktion manifestieren. Die Auspr gung der Pers nlichkeitseigenschaften wurde von 181 Besitzern eines StudiVZ-Profils mithilfe standardisierter Frageb gen erhoben. Anschlie end wurden ihre Profile analysiert. Die Ergebnisse belegten, dass h here Auspr gungen der untersuchten Pers nlichkeitsmerkmale mit einer h heren Selbstdarstellung in Bild und Text sowie virtuellen Interaktion einhergingen.
The heteronuclear E mov effect
Helfrich K.,Hammer H.-W.
EPJ Web of Conferences , 2010, DOI: 10.1051/epjconf/20100302007
Abstract: Ultracold quantum gases with large scattering length show resonant enhancement of three-body loss rates when an E mov trimer is at the scattering threshold. We calculate the three-body loss rates in heteronuclear mixtures of atoms for the case of large scattering length between the unlike atoms. Using zero-range interactions, we present results from the numerical solution of the integral equations for the recombination amplitude in momentum space and extract expressions for the recombination rate constants. Moreover, we calculate the relative positions of loss features for di erent sign of the scattering length and a rst comparison with available experimental data is shown.
Three-boson bound states in nite volume with EFT
Kreuzer S.,Hammer H.-W.
EPJ Web of Conferences , 2010, DOI: 10.1051/epjconf/20100304011
Abstract: The universal properties of a three-boson system with large scattering length are well understood within the framework of E ective Field Theory. They include a geometric spectrum of shallow three-body bound states called “E mov states” and log-periodic dependence of scattering observables on the scattering length. We investigate the modi cation of this spectrum in a nite cubic box using a partial wave expansion. The dependence of the binding energies on the box size is calculated for systems with positive and negative two-body scattering length. We compare the full results to results obtained using an expansion around the in nite volume binding energy. The renormalization of the E ective Field Theory in the nite volume is veri ed explicitly.
Causality and universality in low-energy scattering
Lee D.,Hammer H.-W.
EPJ Web of Conferences , 2010, DOI: 10.1051/epjconf/20100302008
Abstract: We discuss the generalization of Wigner’s causality bounds and Bethe’s integral formula for the e ective range parameter to arbitrary dimension and arbitrary angular momentum. We consider the impact of these constraints on the separation of low- and high-momentum scales and universality in low-energy scattering.
Baseline characteristics of climate, permafrost and land cover from a new permafrost observatory in the Lena River Delta, Siberia (1998–2011)
J. Boike, B. Kattenstroth, K. Abramova, N. Bornemann, A. Chetverova, I. Fedorova, K. Fr b, M. Grigoriev, M. Grüber, L. Kutzbach, M. Langer, M. Minke, S. Muster, K. Piel, E.-M. Pfeiffer, G. Stoof, S. Westermann, K. Wischnewski, C. Wille,H.-W. Hubberten
Biogeosciences (BG) & Discussions (BGD) , 2013,
Abstract: Samoylov Island is centrally located within the Lena River Delta at 72° N, 126° E and lies within the Siberian zone of continuous permafrost. The landscape on Samoylov Island consists mainly of late Holocene river terraces with polygonal tundra, ponds and lakes, and an active floodplain. The island has been the focus of numerous multidisciplinary studies since 1993, which have focused on climate, land cover, ecology, hydrology, permafrost and limnology. This paper aims to provide a framework for future studies by describing the characteristics of the island's meteorological parameters (temperature, radiation and snow cover), soil temperature, and soil moisture. The land surface characteristics have been described using high resolution aerial images in combination with data from ground-based observations. Of note is that deeper permafrost temperatures have increased between 0.3 to 1.3 °C over the last five years. However, no clear warming of air and active layer temperatures is detected since 1998, though winter air temperatures during recent years have not been as cold as in earlier years. Data related to this article are archived under: http://doi. pangaea.de/10.1594/PANGAEA.806233 .
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