bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multimolecular tracers of terrestrial carbon transfer across the pan‐Arctic: 14C characteristics of sedimentary carbon components and their environmental controls
Authors: Feng Xiaojuan , Gustafsson Örjan , Holmes R. Max , Vonk Jorien E. , van Dongen Bart E. , Semiletov Igor P. , Dudarev Oleg V. , Yunker Mark B. , Macdonald Robie W. , Wacker Lukas , Montluçon Daniel B. , Eglinton Timothy I. 
Published: September 2015

AbstractDistinguishing the sources, ages, and fate of various terrestrial organic carbon (OC) pools mobilized from heterogeneous Arctic landscapes is key to assessing climatic impacts on the fluvial release of carbon from permafrost. Through molecular 14C measurements, including novel analyses of suberin‐ and/or cutin‐derived diacids (DAs) and hydroxy fatty acids (FAs), we compared the radiocarbon characteristics of a comprehensive suite of terrestrial markers (including plant wax lipids, cutin, suberin, lignin, and hydroxy phenols) in the sedimentary particles from nine major arctic and subarctic rivers in order to establish a benchmark assessment of the mobilization patterns of terrestrial OC pools across the pan‐Arctic. Terrestrial lipids, including suberin‐derived longer‐chain DAs (C24,26,28), plant wax FAs (C24,26,28), and n‐alkanes (C27,29,31), incorporated significant inputs of aged carbon, presumably from deeper soil horizons. Mobilization and translocation of these “old” terrestrial carbon components was dependent on nonlinear processes associated with permafrost distributions. By contrast, shorter‐chain (C16,18) DAs and lignin phenols (as well as hydroxy phenols in rivers outside eastern Eurasian Arctic) were much more enriched in 14C, suggesting incorporation of relatively young carbon supplied by runoff processes from recent vegetation debris and surface layers. Furthermore, the radiocarbon content of terrestrial markers is heavily influenced by specific OC sources and degradation status. Overall, multitracer molecular 14C analysis sheds new light on the mobilization of terrestrial OC from arctic watersheds. Our findings of distinct ages for various terrestrial carbon components may aid in elucidating fate of different terrestrial OC pools in the face of increasing arctic permafrost thaw.
Tectonic slicing of subducting oceanic crust along plate interfaces: Numerical modeling
Authors: Ruh J. B. , Le Pourhiet L. , Agard Ph. , Burov E. , Gerya T. 
Published: September 2015

AbstractMultikilometer‐sized slivers of high‐pressure low‐temperature metamorphic oceanic crust and mantle are observed in many mountain belts. These blueschist and eclogite units were detached from the descending plate during subduction. Large‐scale thermo‐mechanical numerical models based on finite difference marker‐in‐cell staggered grid technique are implemented to investigate slicing processes that lead to the detachment of oceanic slivers and their exhumation before the onset of the continental collision phase. In particular, we investigate the role of the serpentinized subcrustal slab mantle in the mechanisms of shallow and deep crustal slicing. Results show that spatially homogeneous serpentinization of the sub‐Moho slab mantle leads to complete accretion of oceanic crust within the accretionary wedge. Spatially discontinuous serpentinization of the slab mantle in form of unconnected patches can lead to shallow slicing of the oceanic crust below the accretionary wedge and to its deep slicing at mantle depths depending on the patch length, slab angle, convergence velocity and continental geothermal gradient. P‐T paths obtained in this study are compared to natural examples of shallow slicing of the Crescent Terrane below Vancouver Island and deeply sliced crust of the Lago Superiore and Saas‐Zermatt units in the Western Alps.
Hydrothermal response to a volcano‐tectonic earthquake swarm, Lassen, California
Authors: Ingebritsen S. E. , Shelly D. R. , Hsieh P. A. , Clor L. E. , Seward P. H. , Evans W. C. 
Published: September 2015

AbstractThe increasing capability of seismic, geodetic, and hydrothermal observation networks allows recognition of volcanic unrest that could previously have gone undetected, creating an imperative to diagnose and interpret unrest episodes. A November 2014 earthquake swarm near Lassen Volcanic National Park, California, which included the largest earthquake in the area in more than 60 years, was accompanied by a rarely observed outburst of hydrothermal fluids. Although the earthquake swarm likely reflects upward migration of endogenous H2O‐CO2 fluids in the source region, there is no evidence that such fluids emerged at the surface. Instead, shaking from the modest sized (moment magnitude 3.85) but proximal earthquake caused near‐vent permeability increases that triggered increased outflow of hydrothermal fluids already present and equilibrated in a local hydrothermal aquifer. Long‐term, multiparametric monitoring at Lassen and other well‐instrumented volcanoes enhances interpretation of unrest and can provide a basis for detailed physical modeling.
Quantifying sources and sinks of reactive gases in the lower atmosphere using airborne flux observations
Authors: Wolfe G. M. , Hanisco T. F. , Arkinson H. L. , Bui T. P. , Crounse J. D. , Dean‐Day J. , Goldstein A. , Guenther A. , Hall S. R. , Huey G. , Jacob D. J. , Karl T. , Kim P. S. , Liu X. , Marvin M. R. , Mikoviny T. , Misztal P. K. , Nguyen T. B. , Peischl J. , Pollack I. , Ryerson T. , St. Clair J. M. , Teng A. , Travis K. R. , Ullmann K. , Wennberg P. O. , Wisthaler A. 
Published: September 2015

AbstractAtmospheric composition is governed by the interplay of emissions, chemistry, deposition, and transport. Substantial questions surround each of these processes, especially in forested environments with strong biogenic emissions. Utilizing aircraft observations acquired over a forest in the southeast U.S., we calculate eddy covariance fluxes for a suite of reactive gases and apply the synergistic information derived from this analysis to quantify emission and deposition fluxes, oxidant concentrations, aerosol uptake coefficients, and other key parameters. Evaluation of results against state‐of‐the‐science models and parameterizations provides insight into our current understanding of this system and frames future observational priorities. As a near‐direct measurement of fundamental process rates, airborne fluxes offer a new tool to improve biogenic and anthropogenic emissions inventories, photochemical mechanisms, and deposition parameterizations.
Magnetospheric vortices and their global effect after a solar wind dynamic pressure decrease
Authors: Zhao H. Y. , Shen X. C. , Tang B. B. , Tian A. M. , Shi Q. Q. , Weygand J. M. , Yao Z. H. , Zong Q.‐G. , Fu S. Y. , Yao S. T. , Xiao T. , Pu Z. Y. 
Published: September 2015

AbstractUsing multipoint data from three Time History of Events and Macroscale Interactions during Substorms (THEMIS) satellites, we report a magnetospheric flow vortex driven by a negative solar wind dynamic pressure pulse. The observed vortex rotated in a direction opposite to that associated with positive solar wind dynamic pressure pulses. The vortex was moving tailward, as confirmed by a global magnetohydrodynamics (MHD) simulation. In addition, the equivalent ionospheric currents (EICs) deduced from ground magnetometer station data reveal that a current vortex in the ionosphere near the foot point of the satellites has a rotation sense consistent with that observed in the magnetosphere. The field‐aligned current (FAC) density estimated from three THEMIS satellites is about 0.15 nA/m2, and the total FAC of the vortex is about 1.5–3 × 105 A, on the order of the total FAC in a pseudobreakup, but less than the total FAC in most moderate substorms, 106 A.
A system‐size independent validation of CFD‐DEM for noncohesive particles
Authors: LaMarche Casey Q. , Liu Peiyuan , Kellogg Kevin M. , Weimer Alan W. , Hrenya Christine M. 
Published: September 2015

SignificanceFor the first time, CFD‐DEM simulations of small‐scale fluidized beds are quantitatively validated against large‐scale experiments. Such validation is possible via the identification of a measurement independent of system size, namely defluidization. CFD‐DEM inputs (particle properties and operating conditions) are measured directly. Sphericity is found to be critical, even for highly spherical particles. This size‐independent method of validation is valuable since it allows for validation of CFD‐DEM models without restrictions on system sizes or particle sizes. © 2015 American Institute of Chemical Engineers AIChE J, 61: 4051–4058, 2015
π‐Conjugated Microporous Polymer Films: Designed Synthesis, Conducting Properties, and Photoenergy Conversions
Authors: Gu Cheng , Huang Ning , Chen Youchun , Qin Leiqiang , Xu Hong , Zhang Shitong , Li Fenghong , Ma Yuguang , Jiang Donglin 
Published: September 2015

AbstractConjugated microporous polymers are a unique class of polymers that combine extended π‐conjugation with inherent porosity. However, these polymers are synthesized through solution‐phase reactions to yield insoluble and unprocessable solids, which preclude not only the evaluation of their conducting properties but also the fabrication of thin films for device implementation. Here, we report a strategy for the synthesis of thin films of π‐conjugated microporous polymers by designing thiophene‐based electropolymerization at the solution–electrode interface. High‐quality films are prepared on a large area of various electrodes, the film thickness is controllable, and the films are used for device fabrication. These films are outstanding hole conductors and, upon incorporation of fullerenes into the pores, function as highly efficient photoactive layers for energy conversions. Our film strategy may boost the applications in photocatalysis, energy storage, and optoelectronics.
Sorption of propylene and propane in polyurethane membranes containing silver nanoparticles
Authors: Rezende Carolina Guedes Fioravante , Borges Cristiano Piacsek , Habert Alberto Claudio 
Published: September 2015

ABSTRACTThe preparation of a facilitated transport membrane of polyurethane (PU) containing silver nanoparticles is reported. The propylene and propane sorption was investigated aiming at the selective separation from C3s mixtures. The silver particles were photogenerated in situ into the polyurethane matrix using UV light radiation and silver triflate (AgCF3SO3) as precursor. The morphological properties of these membranes (PUAg) reveled great dispersion of silver particles, which size was smaller than 110 nm. The propylene solubility in PUAg resulted more than four times superior to the one for the pure PU membrane, revealing the high affinity between silver and propylene. Flory–Huggins theory was more accurate to describe the propylene sorption behavior in PUAg than Henry's model. The ideal solubility selectivity of PUAg membrane resulted 24.4, indicating that there is a good potential for an industrial application aiming at the separation of propylene/propane. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42916.
A Simple Method for the Preparation of TiO2/Ag‐AgCl@Polypyrrole Composite and Its Enhanced Visible‐Light Photocatalytic Activity
Authors: Yao Tongjie , Shi Lei , Wang Hao , Wang Fangxiao , Wu Jie , Zhang Xiao , Sun Jianmin , Cui Tieyu 
Published: September 2015

AbstractA novel and facile method was developed to prepare a visible‐light driven TiO2/Ag‐AgCl@polypyrrole (PPy) photocatalyst with Ag‐AgCl nanoparticles supported on TiO2 nanofibers and covered by a thin PPy shell. During the synthesis, the PPy shell and Ag‐AgCl nanoparticles were prepared simultaneously onto TiO2 nanofibers, which simplified the preparation procedure. In addition, because Ag‐AgCl aggregates were fabricated via partly etching the Ag nanoparticles, their size was well controlled at the nanoscale, which was beneficial for improvement of the contact surface area. Compared with reference photocatalysts, the TiO2/Ag‐AgCl@PPy composite exhibited an enhanced photodegradation activity towards rhodamine B under visible‐light irradiation. The superior photocatalytic property originated from synergistic effects between TiO2 nanofibers, Ag‐AgCl nanoparticles and the PPy shell. Furthermore, the TiO2/Ag‐AgCl@PPy composite could be easily separated and recycled without obvious reduction in activity.
Characteristics and role of dynamic membrane layer in anaerobic membrane bioreactors
Authors: Ersahin Mustafa Evren , Tao Yu , Ozgun Hale , Spanjers Henri , van Lier Jules B. 
Published: September 2015

ABSTRACTA submerged anaerobic dynamic membrane bioreactor (AnDMBR) was operated for treatment of concentrated wastewater. The dynamic membrane (DM) or cake layer was characterized on its physicochemical and biological composition and the role of the DM layer in treatment and filtration performances was assessed. The results showed that the DM layer had an important role in organic matter removal. Both organic and inorganic materials, such as sludge particles, soluble microbial products (SMP), extracellular polymeric substances (EPS), and Ca, N, P, Mg precipitations contributed to the DM layer formation. Thus, effective retention of very small particles by the DM layer was achieved. The DM layer had higher microbial diversity and different microbial population composition in comparison to the bulk sludge. Overall, this study provided a better understanding about the DM layer structure in AnDMBRs, which might lead to increased applicability of this promising technology for the treatment of concentrated wastewaters. Biotechnol. Bioeng. 2016;113: 761–771. © 2015 Wiley Periodicals, Inc.
Influence of Bubble‐Surface Contamination on Instantaneous Mass Transfer
Authors: Huang Jie , Saito Takayuki 
Published: September 2015

AbstractThe relationship between instantaneous mass transfer, bubble motions, and bubble‐induced surrounding liquid motions is discussed on the basis of precise measurements in time and space. The influence of bubble‐surface contamination on the above is considered quantitatively through comparison with those in a purified system. The bubble's surface motion, centroid motion, volume, and surface area were acquired precisely from moment to moment using two high‐speed cameras and an own innovative image processing method. The dissolution process of CO2 was visualized via the laser‐induced fluorescence/8‐hydroxypyrene‐1,3,6‐trisulfonic acid (LIF/HPTS) method. Combining these experimental results carefully, the effects of the surfactant on the mass transfer, bubble motions, and vortex mechanism are discussed.
Interpenetration of a 3D Icosahedral M@Ni12 (M=Al, Ga) Framework with Porphyrin‐Reminiscent Boron Layers in MNi9B8
Authors: Zheng Qiang , Wagner Frank R. , Ormeci Alim , Prots Yurii , Burkhardt Ulrich , Schmidt Marcus , Schnelle Walter , Grin Yuri , Leithe‐Jasper Andreas 
Published: September 2015

AbstractTwo ternary borides MNi9B8 (M=Al, Ga) were synthesized by thermal treatment of mixtures of the elements. Single‐crystal X‐ray diffraction data reveal AlNi9B8 and GaNi9B8 crystallizing in a new type of structure within the space group Cmcm and the lattice parameters a=7.0896(3) Å, b=8.1181(3) Å, c=10.6497(4) Å and a=7.0897(5) Å, b=8.1579(4) Å, c=10.6648(7) Å, respectively. The boron atoms build up two‐dimensional layers, which consist of puckered [B16] rings with two tailing B atoms, whereas the M atoms reside in distorted vertices‐condensed [Ni12] icosahedra, which form a three‐dimensional framework interpenetrated by boron porphyrin‐reminiscent layers. An unusual local arrangement resembling a giant metallo‐porphyrin entity is formed by the [B16] rings, which, due to their large annular size of approximately 8 Å, chelate four of the twelve icosahedral Ni atoms. An analysis of the chemical bonding by means of the electron localizability approach reveals strong covalent BB interactions and weak NiNi interactions. Multi‐center dative BNi interaction occurs between the Al–Ni framework and the boron layers. In agreement with the chemical bonding analysis and band structure calculations, AlNi9B8 is a Pauli‐paramagnetic metal.
Deciphering the Mechanism Involved in the Switch On/Off of Molecular Pistons
Authors: Liu Peng , Shao Xueguang , Cai Wensheng 
Published: September 2015

AbstractManufacturing machines converting energy to mechanical work at the molecular level is a vital pathway to explore the microscopic world. A kind of operable molecular engines, composed of β‐cyclodextrin (β‐CD), aryl, alkene and amide moiety was investigated using molecular dynamics simulations combined with free‐energy calculations. To understand how the integrated alkene double bond controls the work performed on the engines, two alkene isomers of the prototype were considered as two molecular engines. The free‐energy profiles delineating the binding process of the amide (Z)‐ and (E)‐isomers for each alkene isomer with 1‐adamantanol indicate that for the alkene (E)‐isomer, the apparent work performed on the amide bond is 1.6 kcal/mol, while the alkene (Z)‐isomer is incapable to perform work. Direct switch on/off of engines caused by the isomerization of the alkene bond was, therefore, witnessed, in line with experimental measurements. Decomposition of the free‐energy profile into different components and structural analyses suggest that the isomerization of the alkene bond controls the position of the aryl unit relative to the cavity of the CD, resulting in the difference among the free‐energy profiles and the stark contrast of the work performed on engines.
First Synthesis and Characterization of Stereoisomers of Choleretic Drug Dihydroxydibutylether
Authors: Yue Qiming , Zhao Yi , Sun Baohou , Hai Li , Guo Li , Wu Yong 
Published: September 2015

AbstractDihydroxydibutylether (DHBE) is a choleretic drug used for the treatment of gallstone and hepatic disorders due to its choleretic activity and hepatoprotective action. The drug is a mixture of three regioisomers. The main regioisomer 3‐(3‐hydroxylbutoxy)‐1‐butanol (III) contains four stereoisomers, including (R)‐3‐((R)‐3‐hydroxylbutoxy)‐1‐butanol (IIIa), (R)‐3‐((S)‐3‐hydroxylbutoxy)‐1‐butanol (IIIb), (S)‐3‐((R)‐3‐hydroxylbutoxy)‐1‐butanol (IIIc) and (S)‐3‐((S)‐3‐hydroxylbutoxy)‐1‐butanol (IIId). In this paper, the four stereoisomers are synthesized separately for the first time.
First Total Synthesis of (±)‐Latifolin and Its Antioxidant Mechanism
Authors: Dai Yihua , Liu Qiaoling , Li Zhifang , Chen Weifeng , Liu Zhongli 
Published: September 2015

AbstractThe first total synthesis of (±)‐latifolin has been accomplished in six steps and 47.8% overall yield. To understand the relative importance of phenolic OH and benzhydryl CH hydrogen on the antioxidant activity of latifolin, 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging assay and density functional theory (DFT) studies were carried out. On scavenging DPPH radical in ethanol, the activity of latifolin (1) bearing phenolic hydrogen is remarkably higher than analogue 10 bearing no phenolic hydrogen. Therefore, Phenolic hydrogen is responsible for latifolin's antioxidant activity rather than benzhydryl CH hydrogen. Furthermore, the 5‐OH BDE is lower than 2′‐OH and 7‐CH BDEs by a DFT calculation, respectively. Based on theoretical results it is definitely concluded that the phenolic 5‐OH plays a major role in the antioxidant activity of latifolin.
Bayesian transformation family selection: Moving toward a transformed Gaussian universe
Authors: Charitidou Efstratia , Fouskakis Dimitris , Ntzoufras Ioannis 
Published: September 2015

AbstractThe problem of transformation selection is thoroughly treated from a Bayesian perspective. Several families of transformations are considered with a view to achieving normality: theBox–Cox, theModulus, theYeo & Johnson, and theDualtransformation. Markov chain Monte Carlo algorithms have been constructed in order to sample from the posterior distribution of the transformation parameterassociated with each competing familyT. We investigate different approaches to constructing compatible prior distributions forover alternative transformation families. Selection and discrimination between different transformation families are attained via posterior model probabilities. Although there is no choice of transformation family that can be universally applied to all problems, empirical evidence suggests that some particular data structures are best treated by specific transformation families. For example, skewness is associated with the Box–Cox family while fat‐tailed distributions are efficiently treated using the Modulus transformation.The Canadian Journal of Statistics43: 600–623; 2015 © 2015 Statistical Society of Canada
Mirror Symmetry Breaking by Chirality Synchronisation in Liquids and Liquid Crystals of Achiral Molecules
Authors: Tschierske Carsten , Ungar Goran 
Published: September 2015

AbstractSpontaneous mirror symmetry breaking is an efficient way to obtain homogeneously chiral agents, pharmaceutical ingredients and materials. It is also in the focus of the discussion around the emergence of uniform chirality in biological systems. Tremendous progress has been made by symmetry breaking during crystallisation from supercooled melts or supersaturates solutions and by self‐assembly on solid surfaces and in other highly ordered structures. However, recent observations of spontaneous mirror symmetry breaking in liquids and liquid crystals indicate that it is not limited to the well‐ordered solid state. Herein, progress in the understanding of a new dynamic mode of symmetry breaking, based on chirality synchronisation of transiently chiral molecules in isotropic liquids and in bicontinuous cubic, columnar, smectic and nematic liquid crystalline phases is discussed. This process leads to spontaneous deracemisation in the liquid state under thermodynamic control, giving rise to long‐term stable symmetry‐broken fluids, even at high temperatures. These fluids form conglomerates that are capable of extraordinary strong chirality amplification, eventually leading to homochirality and providing a new view on the discussion of emergence of uniform chirality in prebiotic systems.
Ultrafast Heme Dynamics of Ferric Cytochrome c in Different Environments: Electronic, Vibrational, and Conformational Relaxation
Authors: Karunakaran Venugopal 
Published: September 2015

AbstractThe excited‐state dynamics of ferric cytochrome c (Cyt c), an important electron‐transfer heme protein, in acidic to alkaline medium and in its unfolded form are investigated by using femtosecond pump–probe spectroscopy, exciting the heme and Tryptophan (Trp) to understand the electronic, vibrational, and conformational relaxation of the heme. At 390 nm excitation, the electronic relaxation of heme is found to be ≈150 fs at different pH values, increasing to 480 fs in the unfolded form. Multistep vibrational relaxation dynamics of the heme, including fast and slow processes, are observed at pH 7. However, in the unfolded form and at pH 2 and 11, fast phases of vibrational relaxation dominate, revealing the energy dissipation occurring through the covalent bond interaction between the heme and the nearest amino acids. A significant shortening of the excited‐state lifetime of Trp is observed at various pH values at 280 nm excitation due to resonance energy transfer to the heme. The longer time constant (25 ps) observed in the unfolded form is attributed to a complete global conformational relaxation of Cyt c.