bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Model for Mass Transport Across the Sediment‐Water Interface
Authors: Voermans Joey J. , Ghisalberti Marco , Ivey Gregory N. 
Published: March 2018

AbstractMolecular diffusion, dispersion, and turbulent diffusion can all contribute to the transport of mass across the sediment‐water interface (SWI). Flow observations across the SWI are critical in the description of these transport processes but are currently very limited as the sediment bed is inaccessible in most experimental approaches. We overcome this constraint by combining refractive‐index matching (RIM) with particle‐tracking velocimetry (PTV). Using measurements of the flow dynamics across the SWI, we propose a mechanistic model that describes the interfacial mass transport over a wide and relevant parameter space. We show there are three transport regimes where molecular, dispersive, or turbulent transport dominates the mass flux of a passive tracer across the SWI. Transitions between these regimes are defined by the permeability Reynolds number, whereKis the sediment permeability,is the shear velocity, andνis the fluid viscosity. In the molecular regime (), mass transport is described by the molecular diffusion coefficient (D). In both the dispersive () and turbulent regimes (), the mass diffusivity is directly proportional to. The model is strongly supported by an extensive data set of published interfacial mass flux observations and provides a tool for describing fluxes across the SWI in aquatic system models.
Blue Water Trade‐Offs With Vegetation in a CO2‐Enriched Climate
Authors: Mankin Justin S. , Seager Richard , Smerdon Jason E. , Cook Benjamin I. , Williams A. Park , Horton Radley M. 
Published: March 2018

AbstractPresent and future freshwater availability and drought risks are physically tied to the responses of surface vegetation to increasing CO2. A single‐model large ensemble identifies the occurrence of colocated warming‐ and CO2‐induced leaf area index increases with summer soil moisture declines. This pattern of “greening” and “drying,” which occurs over 42% of global vegetated land area, is largely attributable to changes in the partitioning of precipitation at the land surface away from runoff and toward terrestrial vegetation ecosystems. Changes in runoff and ecosystem partitioning are inversely related, with changes in runoff partitioning being governed by changes in precipitation (mean and extremes) and ecosystem partitioning being governed by ecosystem water use and surface resistance to evapotranspiration (ET). Projections show that warming‐influenced and CO2‐enriched terrestrial vegetation ecosystems use water that historically would have been partitioned to runoff over 48% of global vegetated land areas, largely in Western North America, the Amazon, and Europe, many of the same regions with colocated greening and drying. These results have implications for how water available for people will change in response to anthropogenic warming and raise important questions about model representations of vegetation water responses to high CO2.
On Mars's Atmospheric Sputtering After MAVEN's First Martian Year of Measurements
Authors: Leblanc F. , Martinez A. , Chaufray J. Y. , Modolo R. , Hara T. , Luhmann J. , Lillis R. , Curry S. , McFadden J. , Halekas J. , Jakosky B. 
Published: March 2018

AbstractMars likely lost a significant part of its atmosphere to space during its history. The sputtering of the atmosphere, by precipitating planetary heavy pickup ions accelerated by the solar wind, is one of the processes that could have significantly contributed to this atmospheric escape, in particular since the cessation of its global magnetic field, 4.0–4.1 Gyr ago. We present a 2 year baseline analysis of Mars Atmosphere and Volatile EvolutioN (MAVEN) observations of the precipitating flux. We use this measurement to model the expected escape rate and exospheric structure induced by this precipitation. We conclude that sputtering signatures in the dayside exosphere will be difficult to identify by MAVEN, and the induced atmospheric escape of O atoms remains orders of magnitude smaller than the expected rate induced by dissociative recombination of O2+ in Mars's ionosphere. On the contrary, deep in the nightside, Mars's sputtering might be the main source of the nonthermal part of the exospheric density profiles of species with mass larger or equal to Ar.
Tracking an Oil Tanker Collision and Spilled Oils in the East China Sea Using Multisensor Day and Night Satellite Imagery
Authors: Sun Shaojie , Lu Yingcheng , Liu Yongxue , Wang Mengqiu , Hu Chuanmin 
Published: March 2018

AbstractSatellite remote sensing is well known to play a critical role in monitoring marine accidents such as oil spills, yet the recent SANCHI oil tanker collision event in January 2018 in the East China Sea indicates that traditional techniques using synthetic aperture radar or daytime optical imagery could not provide timely and adequate coverage. In this study, we show the unprecedented value of Visible Infrared Imaging Radiometer Suite (VIIRS) Nightfire product and Day/Night Band data in tracking the oil tanker's drifting pathway and locations when all other means are not as effective for the same purpose. Such pathway and locations can also be reproduced with a numerical model, with root‐mean‐square error of <15 km. While high‐resolution optical imagery after 4 days of the tanker's sinking reveals much larger oil spill area (>350 km2) than previous reports, the impact of the spilled condensate oil on the marine environment requires further research.
Thermospheric Expansion Associated With Dust Increase in the Lower Atmosphere on Mars Observed by MAVEN/NGIMS
Authors: Liu Guiping , England Scott L. , Lillis Robert J. , Withers Paul , Mahaffy Paul R. , Rowland Douglas E. , Elrod Meredith , Benna Mehdi , Kass David M. , Janches Diego , Jakosky Bruce 
Published: March 2018

AbstractWe present for the first time the dramatic variations in atmospheric composition and density at high altitudes from 170 to 220 km in Mars' neutral thermosphere in response to dust increases in the lower atmosphere, observed by the in situ Neutral Gas Ion Mass Spectrometer onboard the Mars Atmosphere and Volatile EvolutioN satellite. The observations reveal that CO2, Ar, N2, CO, and O densities all increase up to ~200% compared to the longer‐term running median densities. The density increases are seen throughout this altitude region, and the relative variations are seen to be stronger at higher altitudes. Density increases indicating the solar extreme ultraviolet influence are also seen. This study is consistent with that during increased dust load, the whole atmosphere expands and rises, and other processes may also be involved. The results agree with the general circulation model predictions, providing observational evidence for how dust increases affect different atmospheric species in the thermosphere.
Amino Acid Composition Determines Peptide Activity Spectrum and Hot‐Spot‐Based Design of Merecidin
Authors: Wang Xiuqing , Mishra Biswajit , Lushnikova Tamara , Narayana Jayaram Lakshmaiah , Wang Guangshun 
Published: March 2018

AbstractThere is a great interest in developing the only human cathelicidin into therapeutic molecules. The major antimicrobial region of human LL‐37 corresponds to residues 17–32. The resultant peptide GF‐17 shows a broad spectrum of antimicrobial activity against both Gram‐positive and Gram‐negative bacteria. By reducing the hydrophobic content, converting the broad‐spectrum GF‐17 to two narrow‐spectrum peptides (GF‐17d3 and KR‐12) with activity against Gram‐negative bacteria is successful. This study demonstrates that substitution of multiple basic amino acids by hydrophobic alanines makes a broad‐spectrum peptide 17BIPHE2 (designed based on GF‐17d3) active against Staphylococcal pathogens but not other bacteria tested. Taken together, the results reveal distinct charge and hydrophobic requirements for peptides to kill Gram‐positive or Gram‐negative bacteria. This finding is in line with the bioinformatics analysis of the peptides in the Antimicrobial Peptide Database (http://aps.unmc.edu/AP). In addition, a hot‐spot arginine is identified and used to design merecidin with reduced toxicity to human cells. Merecidin protects wax moth larvae (Galleria mellonella) from the infection of methicillin‐resistant Staphylococcus aureus USA300. These new selective peptides constitute interesting candidates for future development.
Graphene Platelets and Their Polymer Composites: Fabrication, Structure, Properties, and Applications
Authors: Shi Ge , Araby Sherif , Gibson Christopher T. , Meng Qingshi , Zhu Shenmin , Ma Jun 
Published: March 2018

AbstractGraphene oxide is extensively compounded with polymers toward a wide variety of applications. Less studied are few‐layer or multi‐layer highly crystalline graphene, both of which are herein named as graphene platelets. This article aims to provide the most recent advancements of graphene platelets and their polymer composites. A first focus lies on cost‐effective fabrication strategies of graphene platelets – intercalation and exfoliation – which work in a relative mass scale, e.g., 5.3 g h−1. As no heavy oxidization is involved, the platelets have high crystalline integrity, e.g., C:O ratio over 8.0, with thicknesses 2–4 nm and lateral dimension up to a few micrometers. Through carefully selecting the solvent for dispersion and the molecules for surface modification, graphene platelets can be liquid‐processable, enabling them to be printed, coated, or compounded with various polymers. A purpose‐designed experiment is undertaken to unravel the effect of reasonable ultrasonication time on the platelet thickness. Typical polymer/graphene platelet composites are critically examined for their preparation, structure, and applications such as thermal management and flexible/stretchable electronic devices. Perspectives on the limitations, current challenges, and future prospects for graphene platelets and their polymer composites are provided.
Molecular Diffusion–Driven Motion in 2D Graphene Film
Authors: Chang Jin , Sheng Lizhi , Wei Tong , Fan Zhuangjun 
Published: March 2018

AbstractHere, a new mode for driving the motion of graphene films on water by organic molecular diffusion is reported. Because of ultralight weight, micro/nanochannels constructed by interlayered sheets, the hydrophobic nature of graphene, and the one‐way 2D diffusion of organic molecules into water induce force/torque for driving the movement of the film. It is worth mentioning that the rectangular film filled with ethanol (1 cm × 2 cm) shows a high rotational speed of 300 rpm on the water. Importantly, the continuous rotation of the graphene film can be realized by continuously adding the collected ethanol from the ethanol–water mixture under visible light irradiation. Moreover, the folded graphene film filled with ethanol can push a porcelain boat (12 g) on water with a velocity of 50 mm s−1. Thus, it is believed that this new driving mode can be applied in the fields of microflow reactors, electric generating device, minisensors, and actuators.
Piezophototronic Effect Enhanced Photoresponse of the Flexible Cu(In,Ga)Se2 (CIGS) Heterojunction Photodetectors
Authors: Qiao Shuang , Liu Jihong , Niu Xiaona , Liang Baolai , Fu Guangsheng , Li Zhiqiang , Wang Shufang , Ren Kailiang , Pan Caofeng 
Published: March 2018

AbstractThe Cu(In,Ga)Se2 (CIGS) heterojunction, as a mature and high efficiency thin‐film solar cell, is rarely studied as a photodetector, especially in flexible substrates. In this paper, the structure of an ITO/ZnO/CdS/CIGS/Mo heterojunction is grown on the polyimide (PI) substrate to form a flexible CIGS heterojunction photodetector. The photodetector can work in a very wide band ranging from 350 to 1200 nm with responsivity up to 1.18 A W−1 (808 nm), detectivity up to 6.56 × 1010 Jones (cmHz1/2 W−1), and response time of 70 (/88) ms, respectively. Moreover, the piezophototronic effect is first used to investigate performance modulation of this device by effectively controlling the separation and transport of carriers at the interface of CdS/ZnO. Interestingly, by externally applying a 0.763% tensile strain, the photoresponsivity and detectivity of the photodetector exhibit a decrease from 1.18 to 0.88 A W−1, and from 6.56 × 1010 to 4.81 × 1010 Jones, respectively, while under a –0.749% externally static compressive strain, the photoresponsivity could be enhanced by ≈75.4% with a maximum of 2.07 A W−1, and the detectivity is improved by ≈66.1% with its peak value up to 10.9 × 1010 Jones. Meanwhile, the response time can be modulated from 99(/116) to 41.3(/42.6) ms. This work suggests that the CIGS heterojunction has great potential in novel applications for piezophototronic sensors and also gives a hint to modulate the performance of other multilayer heterostructures via the piezotronic effect.
Dual Electrostatic Assembly of Graphene Encapsulated Nanosheet‐Assembled ZnO‐Mn‐C Hollow Microspheres as a Lithium Ion Battery Anode
Authors: Xie Qingshui , Liu Pengfei , Zeng Deqian , Xu Wanjie , Wang Laisen , Zhu Zi‐Zhong , Mai Liqiang , Peng Dong‐Liang 
Published: March 2018

AbstractGraphene encapsulated nanosheet‐assembled ZnO‐Mn‐C hierarchical hollow microspheres are produced through a simple yet effective dual electrostatic assembly strategy, followed by a heating treatment in inert atmosphere. The modification of graphene sheets, metal Mn, and in situ carbon leads to form 3D interconnected conductive framework as electron highways. The hollow structure and the open configuration of hierarchical microspheres guarantee good structural stability and rapid ionic transport. More importantly, according to the density functional theory calculations, the oxygen vacancies in the hierarchical microspheres would cause an imbalanced charge distribution and thus the formation of local in‐plane electric fields around oxygen vacancy sites, which is beneficial for the ionic/electronic transport during cycling. Due to this multiscale coordinated design, the as‐fabricated graphene encapsulated nanosheet‐assembled ZnO‐Mn‐C hierarchical hollow microspheres demonstrate good lithium storage properties in terms of high reversible capacity (1094 mA h g−1 at 100 mA g−1), outstanding high‐rate long‐term cycling stability (843 mA h g−1 after 1000 cycles at 2000 mA g−1), and remarkable rate capability (422 mA h g−1 after total 1600 cycles at 5000 mA g−1).
Smart Passivation Materials with a Liquid Metal Microcapsule as Self‐Healing Conductors for Sustainable and Flexible Perovskite Solar Cells
Authors: Chu Kunmo , Song Byong Gwon , Yang Hye‐In , Kim Dong‐Min , Lee Chang Seung , Park Minwoo , Chung Chan‐Moon 
Published: March 2018

AbstractThe electrical repair of device circuits has been considered a main issue in the area of electronic packaging. Demand for self‐healing conductors as cost‐effective and promising materials for prolonging the durability of devices has increased. Recently, diverse designs of self‐healing and deformable circuits have been introduced in virtue of their high stretchability and conductivity. However, encapsulating a liquid metal with a polymer in a micro‐size container is essential for real applications. In this work, core–shell‐structured liquid metal microcapsules (LMCs, diameter = 2–10 µm) are synthesized via in situ polymerization of urea‐formaldehyde onto liquid metal colloids. Passivation films comprising LMC/polymer composites are simply prepared using phase separation between the capsules and the liquid prepolymer. Capsules ruptured by cutting or pressing release and transport liquid metal to the damaged sites, leading to effective recovery of electrical pathways. Such self‐healing of the metal contacts shows the high potential of LMCs for smart passivation of electronic devices. As an example, flexible perovskite solar cells incorporated with the passivation film demonstrate perfect recovery of the photovoltaic parameters immediately after cutting the metal contact, exhibiting a power conversion efficiency (PCE) retention of 99% relative to the initial value (PCE = 15.07%).
Copper Sulfide (CuxS) Nanowire‐in‐Carbon Composites Formed from Direct Sulfurization of the Metal‐Organic Framework HKUST‐1 and Their Use as Li‐Ion Battery Cathodes
Authors: Foley Sarah , Geaney Hugh , Bree Gerard , Stokes Killian , Connolly Sinead , Zaworotko Michael J. , Ryan Kevin M. 
Published: March 2018

AbstractLi‐ion batteries containing cost‐effective, environmentally benign cathode materials with high specific capacities are in critical demand to deliver the energy density requirements of electric vehicles and next‐generation electronic devices. Here, the phase‐controlled synthesis of copper sulfide (CuxS) composites by the temperature‐controlled sulfurization of a prototypal Cu metal‐organic framework (MOF), HKUST‐1 is reported. The tunable formation of different CuxS phases within a carbon network represents a simple method for the production of effective composite cathode materials for Li‐ion batteries. A direct link between the sulfurization temperature of the MOF and the resultant CuxS phase formed with more Cu‐rich phases favored at higher temperatures is further shown. The CuxS/C samples are characterized through X‐ray diffraction (XRD), thermogravimetric analysis (TGA), transmission electron microscopy, and energy dispersive X‐ray spectroscopy (EDX) in addition to testing as Li‐ion cathodes. It is shown that the performance is dependent on both the CuxS phase and the crystal morphology with the Cu1.8S/C‐500 material as a nanowire composite exhibiting the best performance, showing a specific capacity of 220 mAh g−1 after 200 charge/discharge cycles.
Correlation between Geometrically Induced Oxygen Octahedral Tilts and Multiferroic Behaviors in BiFeO3 Films
Authors: Lee Sung Su , Kim Young‐Min , Lee Hyun‐Jae , Seo Okkyun , Jeong Hu Young , He Qian , Borisevich Albina Y. , Kang Boyoun , Kwon Owoong , Kang Seunghun , Kim Yunseok , Koo Tae Yeong , Rhyee Jong‐Soo , Noh Do Young , Cho Beongki , Seo Ji Hui , Lee Jun Hee , Jo Ji Young 
Published: March 2018

AbstractThe equilibrium position of atoms in a unit cell is directly connected to crystal functionalities, e.g., ferroelectricity, ferromagnetism, and piezoelectricity. The artificial tuning of the energy landscape can involve repositioning atoms as well as manipulating the functionalities of perovskites (ABO3), which are good model systems to test this legacy. Mechanical energy from external sources accommodating various clamping substrates is utilized to perturb the energy state of perovskite materials fabricated on the substrates and consequently change their functionalities; however, this approach yields undesired complex behaviors of perovskite crystals, such as lattice distortion, displacement of B atoms, and/or tilting of oxygen octahedra. Owing to complimentary collaborations between experimental and theoretical studies, the effects of both lattice distortion and displacement of B atoms are well understood so far, which leaves us a simple question: Can we exclusively control the positions of oxygen atoms in perovskites for functionality manipulation? Here the artificial manipulation of oxygen octahedral tilt angles within multiferroic BiFeO3 thin films using strong oxygen octahedral coupling with bottom SrRuO3 layers is reported, which opens up new possibilities of oxygen octahedral engineering.
Large‐Scale Synthesis and Medical Applications of Uniform‐Sized Metal Oxide Nanoparticles
Authors: Kwon Hyek Jin , Shin Kwangsoo , Soh Min , Chang Hogeun , Kim Jonghoon , Lee Jisoo , Ko Giho , Kim Byung Hyo , Kim Dokyoon , Hyeon Taeghwan 
Published: March 2018

AbstractThanks to recent advances in the synthesis of high‐quality inorganic nanoparticles, more and more types of nanoparticles are becoming available for medical applications. Especially, metal oxide nanoparticles have drawn much attention due to their unique physicochemical properties and relatively inexpensive production costs. To further promote the development and clinical translation of these nanoparticle‐based agents, however, it is highly desirable to reduce unwanted interbatch variations of the nanoparticles because characterizing and refining each batch are costly, take a lot of effort, and, thus, are not productive. Large‐scale synthesis is a straightforward and economic pathway to minimize this issue. Here, the recent achievements in the large‐scale synthesis of uniform‐sized metal oxide nanoparticles and their biomedical applications are summarized, with a focus on nanoparticles of transition metal oxides and lanthanide oxides, and clarifying the underlying mechanism for the synthesis of uniform‐sized nanoparticles. Surface modification steps to endow hydrophobic nanoparticles with water dispersibility and biocompatibility are also briefly described. Finally, various medical applications of metal oxide nanoparticles, such as bioimaging, drug delivery, and therapy, are presented.
Nonnoble‐Metal‐Based Plasmonic Nanomaterials: Recent Advances and Future Perspectives
Authors: Kim Sungi , Kim Jae‐Myoung , Park Jeong‐Eun , Nam Jwa‐Min 
Published: March 2018

AbstractThe application scope of plasmonic nanostructures is rapidly expanding to keep pace with the ongoing development of various scientific findings and emerging technologies. However, most plasmonic nanostructures heavily depend on rare, expensive, and extensively studied noble metals such as Au and Ag, with the limited choice of elements hindering their broad and practical applications in a wide spectral range. Therefore, abundant and inexpensive nonnoble metals have attracted attention as new plasmonic nanomaterial components, allowing these nonnoble‐metal‐based materials to be used in areas such as photocatalysis, sensing, nanoantennas, metamaterials, and magnetoplasmonics with new compositions, structures, and properties. Furthermore, the use of nonnoble metal hybrids results in newly emerging or synergistic properties not observed from single‐metal component systems. Here, the synthetic strategies and recent advances in nonnoble‐metal‐based plasmonic nanostructures comprising Cu, Al, Mg, In, Ga, Pb, Ni, Co, Fe, and related hybrids are highlighted, and a discussion and perspectives in their synthesis, properties, applications, and challenges are presented.
Nanomaterial‐Based Plasmon‐Enhanced Infrared Spectroscopy
Authors: Yang Xiaoxia , Sun Zhipei , Low Tony , Hu Hai , Guo Xiangdong , García de Abajo F. Javier , Avouris Phaedon , Dai Qing 
Published: March 2018

AbstractSurface‐enhanced infrared absorption (SEIRA) has attracted increasing attention due to the potential of infrared spectroscopy in applications such as molecular trace sensing of solids, polymers, and proteins, specifically fueled by recent substantial developments in infrared plasmonic materials and engineered nanostructures. Here, the significant progress achieved in the past decades is reviewed, along with the current state of the art of SEIRA. In particular, the plasmonic properties of a variety of nanomaterials are discussed (e.g., metals, semiconductors, and graphene) along with their use in the design of efficient SEIRA configurations. To conclude, perspectives on potential applications, including single‐molecule detection and in vivo bioassays, are presented.
Thermal Conductivity of Polymers and Their Nanocomposites
Authors: Xu Xiangfan , Chen Jie , Zhou Jun , Li Baowen 
Published: March 2018

AbstractPolymers are usually considered as thermal insulators, and their applications are limited by their low thermal conductivity. However, recent studies have shown that certain polymers have surprisingly high thermal conductivity, some of which are comparable to that in poor metals or even silicon. Here, the experimental achievements and theoretical progress of thermal transport in polymers and their nanocomposites are outlined. The open questions and challenges of existing theories are discussed. Special attention is given to the mechanism of thermal transport, the enhancement of thermal conductivity in polymer nanocomposites/fibers, and their potential application as thermal interface materials.