bluuebunny/crossref_metadata_2025_split huggingface dataset:
The behavior of iron and zinc stable isotopes accompanying the subduction of mafic oceanic crust: A case study from Western Alpine ophiolites
Authors: Inglis Edward C. , Debret Baptiste , Burton Kevin W. , Millet Marc‐Alban , Pons Marie‐Laure , Dale Christopher W. , Bouilhol Pierre , Cooper Matthew , Nowell Geoff M. , McCoy‐West Alex J. , Williams Helen M. 
Published: June 2017

AbstractArc lavas display elevated Fe3+/ΣFe ratios relative to MORB. One mechanism to explain this is the mobilization and transfer of oxidized or oxidizing components from the subducting slab to the mantle wedge. Here we use iron and zinc isotopes, which are fractionated upon complexation by sulfide, chloride, and carbonate ligands, to remark on the chemistry and oxidation state of fluids released during prograde metamorphism of subducted oceanic crust. We present data for metagabbros and metabasalts from the Chenaillet massif, Queyras complex, and the Zermatt‐Saas ophiolite (Western European Alps), which have been metamorphosed at typical subduction zone P‐T conditions and preserve their prograde metamorphic history. There is no systematic, detectable fractionation of either Fe or Zn isotopes across metamorphic facies, rather the isotope composition of the eclogites overlaps with published data for MORB. The lack of resolvable Fe isotope fractionation with increasing prograde metamorphism likely reflects the mass balance of the system, and in this scenario Fe mobility is not traceable with Fe isotopes. Given that Zn isotopes are fractionated by S‐bearing and C‐bearing fluids, this suggests that relatively small amounts of Zn are mobilized from the mafic lithologies in within these types of dehydration fluids. Conversely, metagabbros from the Queyras that are in proximity to metasediments display a significant Fe isotope fractionation. The covariation of δ56Fe of these samples with selected fluid mobile elements suggests the infiltration of sediment derived fluids with an isotopically light signature during subduction.
A reflecting, steepening, and breaking internal tide in a submarine canyon
Authors: Alberty M. S. , Billheimer S. , Hamann M. M. , Ou C. Y. , Tamsitt V. , Lucas A. J. , Alford M. H. 
Published: June 2017

AbstractSubmarine canyons are common features of the coastal ocean. Although they are known to be hotspots of turbulence that enhance diapycnal transport in their stratified waters, the dynamics of canyon mixing processes are poorly understood. Most studies of internal wave dynamics within canyons have focused on a handful of canyons with along‐axis slopes less steep than semidiurnal (D2) internal wave characteristics (subcritical). Here, we present the first tidally resolving observations within a canyon with a steeply sloping axis (supercritical). A process study consisting of two 24 h shipboard stations and a profiling mooring was conducted in the La Jolla Canyon off the coast of La Jolla, CA. Baroclinic energy flux is oriented up‐canyon and decreases from 182 ±18 W m−1 at the canyon mouth to
W m−1 near the head. The ratio of horizontal kinetic energy to available potential energy and the observed group speed of each mode are lower than expected for freely propagating D2 internal waves at each station, indicating partial reflection. Harmonic analysis reveals that variance is dominated by the D2 tide. Moving up‐canyon, the relative importance of D2 decreases and its higher harmonics are needed to account for a majority of the observed variance, indicating steepening. Steep internal tides cause large isopycnal displacements (∼50 m in 100 m water depth) and high strain events. These events coincide with enhanced O(
m2 s−3) dissipation of turbulent kinetic energy at mid‐depths.
Impact of data assimilation on Eulerian versus Lagrangian estimates of upper ocean transport
Authors: Sperrevik Ann Kristin , Röhrs Johannes , Christensen Kai Håkon 
Published: June 2017

AbstractUsing four‐dimensional variational analysis, we produce an estimate of the state of a coastal region in Northern Norway during the late winter and spring in 1984. We use satellite sea surface temperature and in situ observations from a series of intensive field campaigns, and obtain a more realistic distribution of water masses both in the horizontal and the vertical than a pure downscaling approach can achieve. Although the distribution of Eulerian surface current speeds are similar, we find that they are more variable and less dependent on model bathymetry in our reanalysis compared to a hindcast produced using the same modeling system. Lagrangian drift currents on the other hand are significantly changed, with overall higher kinetic energy levels in the reanalysis than in the hindcast, particularly in the superinertial frequency band.
An intercomparison of multidecadal observational and reanalysis data sets for global total ozone trends and variability analysis
Authors: Bai Kaixu , Chang Ni‐Bin , Shi Runhe , Yu Huijia , Gao Wei 
Published: June 2017

AbstractA four‐step adaptive ozone trend estimation scheme is proposed by integrating multivariate linear regression (MLR) and ensemble empirical mode decomposition (EEMD) to analyze the long‐term variability of total column ozone from a set of four observational and reanalysis total ozone data sets, including the rarely explored ERA‐Interim total ozone reanalysis, from 1979 to 2009. Consistency among the four data sets was first assessed, indicating a mean relative difference of 1% and root‐mean‐square error around 2% on average, with respect to collocated ground‐based total ozone observations. Nevertheless, large drifts with significant spatiotemporal inhomogeneity were diagnosed in ERA‐Interim after 1995. To emphasize long‐term trends, natural ozone variations associated with the solar cycle, quasi‐biennial oscillation, volcanic aerosols, and El Niño–Southern Oscillation were modeled with MLR and then removed from each total ozone record, respectively, before performing EEMD analyses. The resulting rates of change estimated from the proposed scheme captured the long‐term ozone variability well, with an inflection time of 2000 clearly detected. The positive rates of change after 2000 suggest that the ozone layer seems to be on a healing path, but the results are still inadequate to conclude an actual recovery of the ozone layer, and more observational evidence is needed. Further investigations suggest that biases embedded in total ozone records may significantly impact ozone trend estimations by resulting in large uncertainty or even negative rates of change after 2000.
Near‐surface turbulence as a missing link in modeling evapotranspiration‐soil moisture relationships
Authors: Haghighi Erfan , Kirchner James W. 
Published: June 2017

AbstractDespite many efforts to develop evapotranspiration (ET) models with improved parametrizations of resistance terms for water vapor transfer into the atmosphere, estimates of ET and its partitioning remain prone to bias. Much of this bias could arise from inadequate representations of physical interactions near nonuniform surfaces from which localized heat and water vapor fluxes emanate. This study aims to provide a mechanistic bridge from land‐surface characteristics to vertical transport predictions, and proposes a new physically based ET model that builds on a recently developed bluff‐rough bare soil evaporation model incorporating coupled soil moisture‐atmospheric controls. The newly developed ET model explicitly accounts for (1) near‐surface turbulent interactions affecting soil drying and (2) soil‐moisture‐dependent stomatal responses to atmospheric evaporative demand that influence leaf (and canopy) transpiration. Model estimates of ET and its partitioning were in good agreement with available field‐scale data, and highlight hidden processes not accounted for by commonly used ET schemes. One such process, nonlinear vegetation‐induced turbulence (as a function of vegetation stature and cover fraction) significantly influences ET‐soil moisture relationships. Our results are particularly important for water resources and land use planning of semiarid sparsely vegetated ecosystems where soil surface interactions are known to play a critical role in land‐climate interactions. This study potentially facilitates a mathematically tractable description of the strength (i.e., the slope) of the ET‐soil moisture relationship, which is a core component of models that seek to predict land‐atmosphere coupling and its feedback to the climate system in a changing climate.
Observed correlation between the depth to base and top of gas hydrate occurrence from review of global drilling data
Authors: Riedel M. , Collett T. S. 
Published: June 2017

AbstractA global inventory of data from gas hydrate drilling expeditions is used to develop relationships between the base of structure I gas hydrate stability, top of gas hydrate occurrence, sulfate‐methane transition depth, pressure (water depth), and geothermal gradients. The motivation of this study is to provide first‐order estimates of the top of gas hydrate occurrence and associated thickness of the gas hydrate occurrence zone for climate‐change scenarios, global carbon budget analyses, or gas hydrate resource assessments. Results from publically available drilling campaigns (21 expeditions and 52 drill sites) off Cascadia, Blake Ridge, India, Korea, South China Sea, Japan, Chile, Peru, Costa Rica, Gulf of Mexico, and Borneo reveal a first‐order linear relationship between the depth to the top and base of gas hydrate occurrence. The reason for these nearly linear relationships is believed to be the strong pressure and temperature dependence of methane solubility in the absence of large difference in thermal gradients between the various sites assessed. In addition, a statistically robust relationship was defined between the thickness of the gas hydrate occurrence zone and the base of gas hydrate stability (in meters below seafloor). The relationship developed is able to predict the depth of the top of gas hydrate occurrence zone using observed depths of the base of gas hydrate stability within less than 50 m at most locations examined in this study. No clear correlation of the depth to the top and base of gas hydrate occurrences with geothermal gradient and sulfate‐methane transition depth was identified.
Joint Sentinel‐1 and SMAP data assimilation to improve soil moisture estimates
Authors: Lievens H. , Reichle R. H. , Liu Q. , De Lannoy G. J. M. , Dunbar R. S. , Kim S. B. , Das N. N. , Cosh M. , Walker J. P. , Wagner W. 
Published: June 2017

AbstractSMAP (Soil Moisture Active and Passive) radiometer observations at ∼40 km resolution are routinely assimilated into the NASA Catchment Land Surface Model to generate the 9 km SMAP Level‐4 Soil Moisture product. This study demonstrates that adding high‐resolution radar observations from Sentinel‐1 to the SMAP assimilation can increase the spatiotemporal accuracy of soil moisture estimates. Radar observations were assimilated either separately from or simultaneously with radiometer observations. Assimilation impact was assessed by comparing 3‐hourly, 9 km surface and root‐zone soil moisture simulations with in situ measurements from 9 km SMAP core validation sites and sparse networks, from May 2015 to December 2016. The Sentinel‐1 assimilation consistently improved surface soil moisture, whereas root‐zone impacts were mostly neutral. Relatively larger improvements were obtained from SMAP assimilation. The joint assimilation of SMAP and Sentinel‐1 observations performed best, demonstrating the complementary value of radar and radiometer observations.
Episodic surface intrusions in the Yellow Sea during relaxation of northerly winds
Authors: Hu Zifeng , Wang Dong‐Ping , He Xianqiang , Li Mingting , Wei Jun , Pan Delu , Bai Yan 
Published: June 2017

AbstractThe surface currents over the Yellow and East China Seas are mapped from the Geostationary Ocean Color Imager (GOCI). Based on a composite of six intrusion events in January–April, the strong northward surface current in the Yellow Sea is shown to be concentrated along the deep trough, accompanied by a broad northward surface current over the East China Sea. From the corresponding surface winds, the episodic northward surface flow bursts appear to be associated with abrupt changes from the strong northerly winds to weak southerly winds during cold front passages. A three‐dimensional model driven with observed surface winds is used to simulate the observed shelf‐wide response to northerly winds. There is an outstanding agreement between the simulated and observed surface currents. The surface intrusion in the Yellow Sea is shown to be driven primarily by a barotropic longitudinal surface slope, while the strong northward current in the East China Sea is associated with a coastal trapped wave. Moreover, the surface intrusion is associated with a large volume transport, suggesting that the transient intrusions could be important in the northward heat transport. The unprecedented capability of GOCI satellite in providing a regional circulation pattern, in conjunction with complementary model simulations, could contribute greatly to understanding of the dynamics of the Yellow and East China Seas.
Tertiary evolution of the Shimanto belt (Japan): A large‐scale collision in Early Miocene
Authors: Raimbourg Hugues , Famin Vincent , Palazzin Giulia , Yamaguchi Asuka , Augier Romain 
Published: June 2017

AbstractTo decipher the Miocene evolution of the Shimanto belt of southwestern Japan, structural and paleothermal studies were carried out in the western area of Shikoku Island. All units constituting the belt, both in its Cretaceous and Tertiary domains, are in average strongly dipping to the NW or SE, while shortening directions deduced from fault kinematics are consistently orientated NNW‐SSE. Peak paleotemperatures estimated with Raman spectra of organic matter increase strongly across the southern, Tertiary portion of the belt, in tandem with the development of a steeply dipping metamorphic cleavage. Near the southern tip of Ashizuri Peninsula, the unconformity between accreted strata and fore‐arc basin, present along the whole belt, corresponds to a large paleotemperature gap, supporting the occurrence of a major collision in Early Miocene. This tectonic event occurred before the magmatic event that affected the whole belt at ~15 Ma. The associated shortening was accommodated in two opposite modes, either localized on regional‐scale faults such as the Nobeoka Tectonic Line in Kyushu or distributed through the whole belt as in Shikoku. The reappraisal of this collision leads to reinterpret large‐scale seismic refraction profiles of the margins, where the unit underlying the modern accretionary prism is now attributed to an older package of deformed and accreted sedimentary units belonging to the Shimanto belt. When integrated into reconstructions of Philippine Sea Plate motion, the collision corresponds to the oblique collision of a paleo Izu‐Bonin‐Mariana Arc with Japan in Early Miocene.
Preparation of magnetic nanoparticles functionalized with poly (styrene‐2‐acrylamido‐2‐methyl propanesulfonic acid) as novel adsorbents for removal of pharmaceuticals from aqueous solutions
Authors: Hayasi Mozhgan , Saadatjoo Naghi 
Published: June 2017

AbstractThis work describes the removal of three pharmaceuticals, namely ceftriaxone sodium (CFX), diclofenac sodium (DCF) and atenolol (ATN) from water using magnetic poly (styrene‐2‐acrylamido‐2‐methyl propanesulfonic acid) (St‐AMPS) adsorbent. This adsorbent was characterized by several techniques such as FTIR, TEM, TGA, VSM and DLS. Three kinetic models, pseudo‐first‐order, pseudo‐second‐order and intra‐particle diffusion models were used to study the adsorption kinetics. The results showed that the adsorption kinetics of pharmaceuticals onto magnetic poly (St‐AMPS) adsorbent followed the pseudo‐second‐order model and were relatively rapid. In addition, it was found that the intra‐particle diffusion was not the sole rate‐controlling step and the adsorption of pharmaceuticals onto adsorbent occurred via two steps adsorption process. The experimental data were fitted with three isotherm models including Freundlich, Langmuir and Dubinin‐Radushkevich (D‐R). It was found that the adsorption of pharmaceuticals onto magnetic poly (St‐AMPS) nanoparticles was the best described by the Langmuir model. Maximum adsorption capacities of 150.602, 47.824 and 119.904 mg/g were obtained for DCF, ATN and CFX, respectively. Also the obtained free energy from D‐R isotherm (6.19, 4.93 and 6.45 kJ/mol for DCF, ATN and CFX respectively) indicated that the adsorption process was a physiosorption. Magnetic poly (St‐AMPS) adsorbent could be recycled for removal of CFX, DCF and ATN by alkaline aqueous solution (pH 8). Therefore, this adsorbent can act as a promising adsorbent for water treatment processes.
Eco‐Friendly Solvent‐Processed Fullerene‐Free Polymer Solar Cells with over 9.7% Efficiency and Long‐Term Performance Stability
Authors: Park Gi Eun , Choi Suna , Park Seo Yeon , Lee Dae Hee , Cho Min Ju , Choi Dong Hoon 
Published: June 2017

AbstractA wide‐bandgap polymer, (poly[(2,6‐(4,8‐bis(5‐(2‐ethylhexyl)thiophen‐2‐yl)‐benzo[1,2‐b:4,5‐b′]dithiophene))‐alt‐(2,5‐(methyl thiophene carboxylate))]) (3MT‐Th), is synthesized to obtain a complementary broad range absorption when harmonized with 3,9‐bis(2‐methylene‐(3‐(1,1‐dicyanomethylene)‐indanone))‐5,5,11,11‐tetrakis(4‐hexylphenyl)‐dithieno[2,3‐d:2′,3′‐d′]‐s‐indaceno[1,2‐b:5,6‐b′]dithiophene (ITIC). The synthesized regiorandom 3MT‐Th polymer shows good solubility in nonhalogenated solvents. A film of 3MT‐Th:ITIC can be employed for forming an active layer in a polymer solar cell (PSC), with the blend solution containing toluene with 0.25% diphenylether as a nonhalogenated additive. The corresponding PSC devices display a power conversion efficiency of 9.73%. Moreover, the 3MT‐Th‐based PSCs exhibit excellent shelf‐life time of over 1000 h and are operationally stable under continuous light illumination. Therefore, methyl thiophene‐3‐carboxylate in 3MT‐Th is a promising new accepting unit for constructing p‐type polymers used for high‐performance nonfullerene‐type PSCs.
Sinus hypoplasia in the cystic fibrosis rat resolves in the absence of chronic infection
Authors: Grayson Jessica , Tipirneni Kiranya E. , Skinner Daniel F. , Fort Matthew , Cho Do‐Yeon , Zhang Shaoyan , Prince Andrew C. , Lim Dong‐Jin , Mackey Calvin , Woodworth Bradford A. 
Published: June 2017

BackgroundSinus hypoplasia is a hallmark characteristic in cystic fibrosis (CF). Chronic rhinosinusitis (CRS) is nearly universal from a young age, impaired sinus development could be secondary to loss of the cystic fibrosis transmembrane conductance regulator (CFTR) or consequences of chronic infection during maturation. The objective of this study was to assess sinus development relative to overall growth in a novel CF animal model.MethodsSinus development was evaluated in CFTR−/− and CFTR+/+ rats at 3 stages of development: newborn; 3 weeks; and 16 weeks. Microcomputed tomography (microCT) scanning, cultures, and histology were performed. Three‐dimensional sinus and skull volumes were quantified.ResultsAt birth, sinus volumes were decreased in CFTR−/− rats compared with wild‐type rats (mean ± SEM: 11.3 ± 0.85 mm3 vs 14.5 ± 0.73 mm3; p < 0.05), despite similar weights (8.4 ± 0.46 gm vs 8.3 ± 0.51 gm; p = 0.86). CF rat weights declined by 16 weeks (378.4 ± 10.6 gm vs 447.4 ± 15.9 gm; p < 0.05), sinus volume increased similar to wild‐type rats (201.1 ± 3.77 gm vs 203.4 ± 7.13 gm; p = 0.8). The ratio of sinus volume to body weight indicates hypoplasia present at birth (1.37 ± 0.12 vs 1.78 ± 0.11; p < 0.05) and showed an increase compared with CFTR+/+ animals by 16 weeks (0.53 ± 0.02 vs 0.46 ± 0.02; p < 0.05). Rats did not develop histologic evidence of chronic infection.ConclusionCF rat sinuses are smaller at birth, but develop volumes similar to wild‐type rats with maturation. This suggests that loss of CFTR may confer sinus hypoplasia at birth, but normal development ensues without chronic sinus infection.
Controlled Growth of Monocrystalline Organo‐Lead Halide Perovskite and Its Application in Photonic Devices
Authors: Mao Wenxin , Zheng Jialu , Zhang Yupeng , Chesman Anthony S. R. , Ou Qingdong , Hicks Jamie , Li Feng , Wang Ziyu , Graystone Brenton , Bell Toby D. M. , Rothmann Mathias Uller , Duffy Noel W. , Spiccia Leone , Cheng Yi‐Bing , Bao Qiaoliang , Bach Udo 
Published: June 2017

AbstractOrgano‐lead halide perovskites (OHPs) have recently emerged as a new class of exceptional optoelectronic materials, which may find use in many applications, including solar cells, light emitting diodes, and photodetectors. More complex applications, such as lasers and electro‐optic modulators, require the use of monocrystalline perovskite materials to reach their ultimate performance levels. Conventional methods for forming single crystals of OHPs like methylammonium lead bromide (MAPbBr3) afford limited control over the product morphology, rendering the assembly of defined microcavity nanostructures difficult. We overcame this by synthesizing for the first time (MA)[PbBr3]⋅DMF (1), and demonstrating its facile transformation into monocrystalline MAPbBr3 microplatelets. The MAPbBr3 microplatelets were tailored into waveguide based photonic devices, of which an ultra‐low propagation loss of 0.04 dB μm−1 for a propagation distance of 100 μm was demonstrated. An efficient active electro‐optical modulator (AEOM) consisting of a MAPbBr3 non‐linear arc waveguide was demonstrated, exhibiting a 98.4 % PL intensity modulation with an external voltage of 45 V. This novel synthetic approach, as well as the demonstration of effective waveguiding, will pave the way for developing a wide range of photonic devices based on organo‐lead halide perovskites.
Nanoscale Chemical Imaging of Interfacial Monolayers by Tip‐Enhanced Raman Spectroscopy
Authors: Shao Feng , Müller Vivian , Zhang Yao , Schlüter A. Dieter , Zenobi Renato 
Published: June 2017

AbstractWe report an investigation of interfacial fluorinated hydrocarbon (carboxylic‐fantrip) monolayers by nanoscale imaging using tip‐enhanced Raman spectroscopy (TERS) and density functional theory (DFT) calculations. By comparing TERS images of a sub‐monolayer prepared by spin‐coating and a π–π‐stacked monolayer on Au(111) in which the molecular orientation is confined, specific Raman peaks shift and line widths narrow in the transferred LB monolayer. Based on DFT calculations that take into account dispersion corrections and surface selection rules, these specific effects are proposed to originate from π–π stacking and molecular orientation restriction. TERS shows the possibility to distinguish between a random and locked orientation with a spatial resolution of less than 10 nm. This work combines experimental TERS imaging with theoretical DFT calculations and opens up the possibility of studying molecular orientations and intermolecular interaction at the nanoscale and molecular level.