bluuebunny/crossref_metadata_2025_split huggingface dataset:
Linking groundwater use and stress to specific crops using the groundwater footprint in the Central Valley and High Plains aquifer systems, U.S.
Authors: Esnault Laurent , Gleeson Tom , Wada Yoshihide , Heinke Jens , Gerten Dieter , Flanary Elizabeth , Bierkens Marc F. P. , van Beek Ludovicus P. H. 
Published: June 2014

AbstractA number of aquifers worldwide are being depleted, mainly by agricultural activities, yet groundwater stress has not been explicitly linked to specific agricultural crops. Using the newly developed concept of the groundwater footprint (the area required to sustain groundwater use and groundwater‐dependent ecosystem services), we develop a methodology to derive crop‐specific groundwater footprints. We illustrate this method by calculating high‐resolution groundwater footprint estimates of crops in two heavily used aquifer systems: the Central Valley and High Plains, U.S. In both aquifer systems, hay and haylage, corn, and cotton have the largest groundwater footprints, which highlights that most of the groundwater stress is induced by crops meant for cattle feed. Our results are coherent with other studies in the High Plains but suggest lower groundwater stress in the Central Valley, likely due to artificial recharge from surface water diversions which were not taken into account in previous estimates. Uncertainties of recharge and irrigation application efficiency contribute the most to the total relative uncertainty of the groundwater footprint to aquifer area ratios. Our results and methodology will be useful for hydrologists, water resource managers, and policy makers concerned with which crops are causing the well‐documented groundwater stress in semiarid to arid agricultural regions around the world.
The 1891 submarine eruption offshore Pantelleria Island (Sicily Channel, Italy): Identification of the vent and characterization of products and eruptive style
Authors: Conte A. M. , Martorelli E. , Calarco M. , Sposato A. , Perinelli C. , Coltelli M. , Chiocci F. L. 
Published: June 2014

AbstractHigh‐resolution bathymetry and seafloor sampling have been used to characterize the 1891 submarine eruption of the Pantelleria volcanic complex. This submarine eruption has been documented mainly by historical reports, describing basaltic scoria bombs floating on the sea surface (i.e., lava balloons). In this study, the 1891 eruptive vent has been identified as a small cone (volume of ∼700,000 m3) rising ∼90 m from 350 m w.d., and located within a newly discovered submarine volcanic field covering a wide area offshore from the NW coast of Pantelleria; recently, Kelly et al. (2012) confirmed this location by a multibeam and ROV survey. Pyroclasts from the 1891 eruption crop out directly on the seafloor and are fresh scoria clasts (i.e., small bombs, bomb fragments, and lapilli) and glass ash‐sized grains; both have been characterized in their morphology, textures, and geochemistry. The distinctive vesicularity and crystallization characteristics displayed by the scoriaceous pyroclasts reflect modes of degassing in both syn and posteruptive regimes; these characteristics, along with the distribution of deposits suggest for the strongest eruptive phase of the 1891 eruption a style analogous to Hawaiian fountaining. Glass grains from a buoyant plume were dispersed northward from the vent, up to distances of 1.5 km, redirected by the Levantine Intermediate Water. The identification of the 1891 submarine eruptive vent offshore Pantelleria, as well as the features of erupted pyroclasts improve our knowledge of submarine explosive eruptions that occur at shallow‐intermediate depths and, among these, of the rare eruptions producing lava balloons.
Intensity of the geomagnetic field in Europe for the last 3 ka: Influence of data quality on geomagnetic field modeling
Authors: Pavón‐Carrasco Francisco Javier , Gómez‐Paccard Miriam , Hervé Gwenaël , Osete María Luisa , Chauvin Annick 
Published: June 2014

AbstractOne of the main challenges of paleomagnetic research is to obtain high‐resolution geomagnetic field intensity reconstructions. For the last millennia, these reconstructions are mostly based on archeomagnetic data. However, the quality of the intensity data available in the databases is very variable, and the high scatter observed in the records clearly suggests that some of them might not be reliable. In this work we investigate how the geomagnetic field intensity reconstructions and, hence, our present knowledge of the geomagnetic field in the past, are affected by the quality of the data selected for modeling the Earth's magnetic field. For this purpose we rank the European archeointensity data in four quality categories following widely accepted paleomagnetic criteria based on the methodology used during the laboratory treatment of the samples and on the number of specimens retained to calculate the mean intensities. Four geomagnetic field regional models have been implemented by applying the revised spherical cap harmonic analysis to these four groups of input data. Geomagnetic field models strongly depend on the used data set. The model built using all the available data (without any preselection) appears to be the less accurate, indicating some internal inconsistencies of the data set. In addition, some features of this model are clearly dominated by the less reliable archeointensity data, suggesting that such features might not reflect real variations of the past geomagnetic field. On the contrary, the regional model built on selected high‐quality intensity data shows a very consistent intensity pattern at the European scale, confirming that the main intensity changes observed in Europe in the recent history of the geomagnetic field occurred at the continental scale.
Segmentation of the Sumatran fault
Authors: Burton Paul W. , Hall Thomas R. 
Published: June 2014

AbstractSegmentation of the Sumatran fault is discerned using an analytical approach in which ak‐means algorithm partitions earthquakes into clusters of seismicity along the fault. Clusters are tessellated into segment zones from which segment lengths and maximum credible magnitude are estimated. Decreasing the depth of seismicity sampled from 70 to 60 to 50 km reduces interaction with deeper seismicity, and results from thek‐means algorithm initially suggest that the fault hasK = 14, 16, and 16 clusters, respectively. After inspection, it becomes clear that the optimum number of clusters is 16. The 16 cluster model developed into zones generates segment lengths ranging from 22 to 196 km and maximum earthquake potentials in the range ofMw6.5–7.8.The Sumatran fault is dominated by eight great central segments distributed approximately symmetrically about Lake Maninjau. These central fault segments dominate the hazard, which is less in the far north because segments are shorter.
The Siding Spring cometary encounter with Mars: A natural experiment for the Martian atmosphere?
Authors: Moores John E. , McConnochie Timothy H. , Ming Douglas W. , Archer Paul Douglas , Schuerger Andrew C. 
Published: June 2014

AbstractOn 19 October 2014 comet C/2013 A1 will encounter Mars. The planet is anticipated to pass through the coma resulting in a greater than four order‐of‐magnitude increase in the accretion of dust with 430 tonnes of dust with diameters between 1 µm and 12.4 mm surviving atmospheric passage. At high altitude, the dust would impact temperature and may affect limb dust extinction and cloud formation. The UV photolysis of the organic carbon content of the dust, 1.9 to 4.6 tonnes, would have a negligible effect on atmospheric methane. Should C/2013 A1 brighten, increases in upper atmospheric accretion of coma particles will exceed the background dust and the population of small coma particles may be constrained from orbital measurements. For M1 < –1.3, methane produced might be measurable by the Sample Analysis at Mars Tunable Laser Spectrometer instrument onboard Curiosity.
Detection of tsunami‐driven phase and amplitude perturbations of subionospheric VLF signals following the 2010 Chile earthquake
Authors: Rozhnoi A. , Shalimov S. , Solovieva M. , Levin B. , Shevchenko G. , Hayakawa M. , Hobara Y. , Walker S. N. , Fedun V. 
Published: June 2014

AbstractWe report on specific fluctuations in phase and amplitude of VLF signals that correlate both spatially and temporally with the passage of the tsunamis recorded by the Deep‐ocean Assessments and Reporting of Tsunamis bottom pressure stations. Measurements from the VLF/LF receiver sited in Petropavlovsk‐Kamchatsky and sensor buoys placed throughout the Pacific Ocean at great distances (Hawaii and Japan) from the epicenter are consistent with the hypothesis that the ocean tsunami following the Chile earthquake on 27 February 2010 radiated internal gravity waves which propagated through the lower ionosphere.
Mediators of the Relationship Between Life Events and Memory Functioning in a Community Sample of Adults
Authors: Korten Nicole C. M. , Sliwinski Martin J. , Comijs Hannie C. , Smyth Joshua M. 
Published: June 2014

SummaryThe present study examines the association of frequency and severity of life events with memory functioning in a community sample of adults. We tested the hypothesis that stress‐related cognitive interference mediated the effects of recent life events on cognition, in addition to examining the potential roles of fatigue, sleep disturbances, and depression. The sample consisted of 310 adults (age range 19–83 years) who received a battery of cognitive tests assessing their primary memory, episodic memory, and working memory. Individuals rated how stressful previous life events were when they occurred, as well as how stressful the events were for them currently. Ratings of current but not past severity were negatively associated with working memory performance. Both stress‐related cognitive interference and depressive symptoms independently mediated this association. These findings highlight the importance of intrusive and avoidant thinking as a potential focus of psychosocial treatment for remediating stress‐related memory dysfunction. Copyright © 2014 John Wiley & Sons, Ltd.
Implementation Intentions Improve Prospective Memory and Inhibition Performances in Older Adults: The Role of Visualization
Authors: Burkard Christina , Rochat Lucien , Emmenegger Joëlle , Juillerat Van der Linden Anne‐Claude , Gold Gabriel , Van der Linden Martial 
Published: June 2014

SummaryImplementation intentions have been shown to be a very effective strategy in improving prospective memory in older adults. However, their efficacy in improving inhibition has never been assessed in aging. We thus examined the efficacy of implementation intentions in a prospective memory task and an inhibition task in 87 older participants. Following a crossover design, half of the participants were instructed to form an implementation intention in the prospective memory task, the other half in the inhibition task. The moderating role of working memory, visualization and verbalization habits, and impulsivity were also assessed. Regression analyses revealed that for both tasks, participants benefited from implementation intentions but only if they were used to using visual strategies in daily life. The efficacy of implementation intentions was not moderated by working memory, impulsivity, or the use of verbal strategies in everyday life. Copyright © 2014 John Wiley & Sons, Ltd.
Insights into the Decomposition of Olefin Metathesis Precatalysts
Authors: Manzini Simone , Poater Albert , Nelson David J. , Cavallo Luigi , Slawin Alexandra M. Z. , Nolan Steven P. 
Published: June 2014

AbstractThe decomposition of a series of benzylidene, methylidene, and 3‐phenylindenylidene complexes has been probed in alcohol solution in the presence of base. Tricyclohexylphosphane‐containing precatalysts are shown to yield [RuCl(H)(H2)(PCy3)2] in isopropyl alcohol solutions, while 3‐phenylindenylidene complexes lead to η5‐(3‐phenyl)indenyl products. The potential‐energy surfaces for the formation of the latter species have been probed using density functional theory studies.
Enantioselektive Katalyse der intermolekularen [2+2]‐Photocycloaddition von 2‐Pyridonen mit Acetylendicarbonsäureestern
Authors: Maturi Mark M. , Bach Thorsten 
Published: June 2014

AbstractIntermolekulare [2+2]‐Photocycloadditionen sind die vielseitigsten und am breitesten anwendbaren Reaktionen der Photochemie. Es gelang nun zum ersten Mal, solche Reaktionen durch Verwendung eines chiralen Triplett‐Sensibilisators mit hoher Enantioselektivität (bis zu 92 % ee) durchzuführen. Die niedrige Katalysatorbeladung (2.5–5 Mol‐%) belegt die hohe Effektivität des Prozesses sowohl bezüglich der Reaktionsbeschleunigung als auch bezüglich der Differenzierung enantiotoper Seiten des Substrats. Hierbei sind nichtkovalente Wechselwirkungen (Wasserstoffbrücken) beteiligt, die für eine Fixierung des Substrats in der chiralen Katalysatorumgebung sorgen. Die hohe Dichte von funktionellen Gruppen in den Produkten eröffnet zahlreiche Möglichkeiten für weitere präparative Transformationen.
Catalytic Ethanolysis of Kraft Lignin into High‐Value Small‐Molecular Chemicals over a Nanostructured α‐Molybdenum Carbide Catalyst
Authors: Ma Rui , Hao Wenyue , Ma Xiaolei , Tian Ye , Li Yongdan 
Published: June 2014

AbstractWe report the complete ethanolysis of Kraft lignin over an α‐MoC1−x/AC catalyst in pure ethanol at 280 °C to give high‐value chemicals of low molecular weight with a maximum overall yield of the 25 most abundant liquid products (LP25) of 1.64 g per gram of lignin. The LP25 products consisted of C6–C10 esters, alcohols, arenes, phenols, and benzyl alcohols with an overall heating value of 36.5 MJ kg−1. C6 alcohols and C8 esters predominated and accounted for 82 wt % of the LP25 products. No oligomers or char were formed in the process. With our catalyst, ethanol is the only effective solvent for the reaction. Supercritical ethanol on its own degrades Kraft lignin into a mixture of small molecules and molecular fragments of intermediate size with molecular weights in the range 700–1400, differing in steps of 58 units, which is the weight of the branched‐chain linkage C3H6O in lignin. Hydrogen was found to have a negative effect on the formation of the low‐molecular‐weight products.
Graphitic Carbon Nitride Nanosheet–Carbon Nanotube Three‐Dimensional Porous Composites as High‐Performance Oxygen Evolution Electrocatalysts
Authors: Ma Tian Yi , Dai Sheng , Jaroniec Mietek , Qiao Shi Zhang 
Published: June 2014

AbstractA new class of highly efficient oxygen evolution catalysts has been synthesized through the self‐assembly of graphitic carbon nitride nanosheets and carbon nanotubes, driven by π–π stacking and electrostatic interactions. Remarkably, the catalysts exhibit higher catalytic oxygen evolution activity and stronger durability than Ir‐based noble‐metal catalysts and display the best performance among the reported nonmetal catalysts. This good result is attributed to the high nitrogen content and the efficient mass and charge transfer in the porous three‐dimensional nanostructure.
The Virtue of Defects: Stable Bromine Production by Catalytic Oxidation of Hydrogen Bromide on Titanium Oxide
Authors: Moser Maximilian , Czekaj Izabela , López Núria , Pérez‐Ramírez Javier 
Published: June 2014

AbstractRutile TiO2 is a heavily investigated oxide with, to date, scarce applications in industrial catalysis. The inactivity of this material in oxidations has been related to its inability to dissociate molecular oxygen. Herein we show how rutile catalyzes the oxidation of HBr to Br2 through defect states that are introduced during the reaction. The identification of active, stable, and abundant materials for bromine production is key to the future implementation of Br2‐mediated alkane functionalization processes. The catalytic properties of TiO2 are discussed in comparison to expensive rutile‐type oxides, such as RuO2 and IrO2, on the basis of surface characterization and molecular modeling.
Mechanism and kinetics of ultra‐high molecular weight polytetrafluoroethylene sintering
Authors: Ganguly Ranadip , Lesser Alan J. 
Published: June 2014

ABSTRACTThe effect of sintering time on the melt evolution of Ultra‐High Molecular Weight Polytetrafluoroethylene was studied in situ by high temperature Wide Angle X‐ray Scattering, and by cyclic thermal loading profiles within a Differential Scanning Calorimeter (DSC) and Thermo‐Mechanical Analyzer (TMA). Results obtained from these techniques support the concept of molecular ordering in the melt state as a function of sintering time well above the melting temperature. TMA, which is not a conventional technique for monitoring thermal transitions, is shown to be sensitive enough for such purposes. Both DSC and TMA exhibit nonequilibrium melt behavior even 30°C above its equilibrium melting temperature for long time periods. A correlation between the DSC and TMA results is established. The cyclic thermal profile leads to a dramatic growth in enthalpy of crystallization/melting. The mechanism for this growth is associated with two independent processes; isothermal annealing at the sintering temperature and lamellar thickening in the solid state. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40967.
Enzymatic and ionic crosslinked gelatin/K‐carrageenan IPN hydrogels as potential biomaterials
Authors: Wen Cai , Lu Lingling , Li Xinsong 
Published: June 2014

ABSTRACTHydrogels of a natural origin have attracted considerable attention in the field of tissue engineering due to their resemblance to ECM, defined degradability and compatibility with biological systems. In this study, we introduced carrageenan into a gelatin network, creating IPN hydrogels through biological methods of enzymatic and ionic crosslinking. Their gelation processes were monitored and confirmed by rheology analysis. The combination of biochemical and physical crosslinking processes enables the formation of biohydrogels with tunable mechanical properties, swelling ratios and degradation behaviors while maintaining the biocompatibilities of natural materials. The mechanical strength increased with an increase in carrageenan content while swelling ratio and degradability decreased correspondingly. In addition, the IPN hydrogels were shown to support adhesion and proliferation of L929 cell line. All the results highlighted the use of biological crosslinked gelatin‐carrageenan IPN hydrogels in the context of tissue engineering. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2014,131, 10.1002/app.40975.
Shewhart‐ und CUSUM‐Kontrollkarten zur gleichzeitigen Prozesssteuerung und Konformitätsbewertung
Authors: Schmidt Wolfram , Kühne Hans‐Carsten , Haamkens Frank 
Published: June 2014

AbstractIm Hinblick auf die Konformitätsbewertung der Druckfestigkeit von Beton wird es in der für 2014 geplanten Fassung der EN 206 signifikante Änderungen geben. Neben den bisher bekannten Verfahren werden auch sogenannte Kontrollkartensysteme als Konformitätsnachweis zugelassen. Dabei können beliebige Kontrollkartensysteme verwendet werden, sofern nachgewiesen werden kann, dass der maximale Durchschlupf (Average Outgoing Quality Limit, AOQL) 5 % beträgt. Im informativen Normenanhang werden zwei grundlegende Verfahren, das sogenannte Shewhart‐Verfahren sowie das CUSUM‐Verfahren (Cumulative Sum) beschrieben, welche beide die Forderung an das AOQL erfüllen.Kontrollkartensysteme sind eigentlich Werkzeuge zur Prozesssteuerung. Sie können effektiv dabei helfen, die Produktion technisch, ökonomisch und ökologisch zu optimieren. Allerdings sind Kontrollkarten deutlich komplexer in der Anwendung als die bisher normativ erfassten Methoden. Der vorliegende Beitrag stellt die neuen Verfahren und deren Besonderheiten anhand von Beispielen vor. Darüber hinaus werden der Zusatznutzen bei sachgerechter Anwendung im Vergleich und Vor‐ und Nachteile zu den bisherigen Verfahren dargestellt und diskutiert.Shewhart and CUSUM Control Charts for simultaneous process control and conformity assessment – New conformity verification methods for the upcoming EN 206With regard to the conformity assessment of the compressive strength of concrete, there will be significant changes in the EN 206, which is scheduled for publication in 2014. So called control chart systems will be approved supplementary to the existing methods. Any control chart can be used as long as the system can grant an average outgoing quality limit (AOQL) of 5 %. The informative appendix of the standard presents two fundamental control chart methods, the so called Shewhart method and the CUSUM method (cumulative sum), both of which fulfill the required AOQL.Control card systems are actually tools for process control. They can effectively help to optimise production processes technically, economically, and ecologically. However, control charts are much more complex to use than the methods known from the recently applied standard. This paper presents these new methods and their characteristics using examples. Furthermore, the additional benefit of these systems is illustrated and advantages and disadvantages are discussed in comparison to existing methods.
Tunnel Königshainer Berge – Vom Brandschaden zum Instandsetzungskonzept
Authors: Schmidt Jörg , Orgass Marko , Renger Steffen , Dehn Frank 
Published: June 2014

AbstractAm 18. Mai 2013 kam es ca. 600 m vor dem östlichen Tunnelportal zu einem LKW‐Brand in der Südröhre des Tunnels Königshainer Berge. Nach dem Brand waren im Bereich der Unglücksstelle Betonabplatzungen festzustellen. Zur Bewertung des Schädigungsgrads an Tunnelschale, Dichtung, Dränage, Kabelleerrohren, Kappen, Entwässerung, Schlitzrinne, Markierung und Fahrbahn wurden mit dem Ziel der Ableitung von Instandsetzungsmaßnahmen experimentelle Untersuchungen und numerische Berechnungen durchgeführt. Unter Zugrundelegung der ermittelten Brandlast wurde die Temperaturbeanspruchung der Tunnelschale orts‐ und zeitabhängig bestimmt, um mit diesen Informationen das Durchwärmungsverhalten zu berechnen und die statisch‐konstruktiven Auswirkungen auch im Vergleich zu den experimentellen Untersuchungen und Werkstoffprüfungen zu verifizieren. Im Ergebnis der Untersuchungen konnte ein Instandsetzungskonzept für den Konstruktionsbeton abgeleitet und umgesetzt werden.Tunnel Königshainer Berge from fire incident to repair conceptOn May 18, 2013, a truck fire happened in the southern tube of the Tunnel Königshainer Berge – 600 m before the eastern tunnel portal. After the fire, concrete spalling was observed in the crash area. For the evaluation of the damage degree of tunnel lining, sealing, drainage, cable ducts, sidewalks etc. experimental investigations and numerical calculations have been conducted in order to derive repair measures. On the basis of the evaluated fire load, the temperature loading on the tunnel lining was determined – both site‐ and time‐orientated. These information were used to calculate the temperature ingress and distribution and to verify the static and structural effects in comparison to the experimental investigations and material tests. As a conclusion, a repair concept for the structural concrete was derived and executed.