bluuebunny/crossref_metadata_2025_split huggingface dataset:
Real‐Time Detection of Rupture Development: Earthquake Early Warning Using P Waves From Growing Ruptures
Authors: Kodera Yuki 
Published: December 2017

AbstractLarge earthquakes with long rupture durations emit P wave energy throughout the rupture period. Incorporating late‐onset P waves into earthquake early warning (EEW) algorithms could contribute to robust predictions of strong ground motion. Here I describe a technique to detect in real time P waves from growing ruptures to improve the timeliness of an EEW algorithm based on seismic wavefield estimation. The proposed P wave detector, which employs a simple polarization analysis, successfully detected P waves from strong motion generation areas of the 2011 Mw 9.0 Tohoku‐oki earthquake rupture. An analysis using 23 large (M ≥ 7) events from Japan confirmed that seismic intensity predictions based on the P wave detector significantly increased lead times without appreciably decreasing the prediction accuracy. P waves from growing ruptures, being one of the fastest carriers of information on ongoing rupture development, have the potential to improve the performance of EEW systems.
A Magnetohydrodynamic Modeling of the Interchange Cycle for Oblique Northward Interplanetary Magnetic Field
Authors: Watanabe Masakazu , Fujita Shigeru , Tanaka Takashi , Kubota Yasubumi , Shinagawa Hiroyuki , Murata Ken T. 
Published: December 2017

AbstractWe perform numerical modeling of the interchange cycle in the magnetosphere‐ionosphere convection system for oblique northward interplanetary magnetic field (IMF). The interchange cycle results from the coupling of IMF‐to‐lobe reconnection and lobe‐to‐closed reconnection. Using a global magnetohydrodynamic simulation code, for an IMF clock angle of 20° (measured from due north), we successfully reproduced the following features of the interchange cycle. (1) In the ionosphere, for each hemisphere, there appears a reverse cell circulating exclusively in the closed field line region (the reciprocal cell). (2) The topology transition of the magnetic field along a streamline near the equatorial plane precisely represents the magnetic flux reciprocation during the interchange cycle. (3) Field‐aligned electric fields on the interplanetary‐open separatrix and on the open‐closed separatrix are those that are consistent with IMF‐to‐lobe reconnection and lobe‐to‐closed reconnection, respectively. These three features prove the existence of the interchange cycle in the simulated magnetosphere‐ionosphere system. We conclude that the interchange cycle does exist in the real solar wind‐magnetosphere‐ionosphere system. In addition, the simulation revealed that the reciprocal cell described above is not a direct projection of the diffusion region as predicted by the “vacuum” model in which diffusion is added a priori to the vacuum magnetic topology. Instead, the reciprocal cell is a consequence of the plasma convection system coupled to the so‐called NBZ (“northward Bz”) field‐aligned current system.
Global MHD Simulations of the Earth's Bow Shock Shape and Motion Under Variable Solar Wind Conditions
Authors: Mejnertsen L. , Eastwood J. P. , Hietala H. , Schwartz S. J. , Chittenden J. P. 
Published: December 2017

AbstractEmpirical models of the Earth's bow shock are often used to place in situ measurements in context and to understand the global behavior of the foreshock/bow shock system. They are derived statistically from spacecraft bow shock crossings and typically treat the shock surface as a conic section parameterized according to a uniform solar wind ram pressure, although more complex models exist. Here a global magnetohydrodynamic simulation is used to analyze the variability of the Earth's bow shock under real solar wind conditions. The shape and location of the bow shock is found as a function of time, and this is used to calculate the shock velocity over the shock surface. The results are compared to existing empirical models. Good agreement is found in the variability of the subsolar shock location. However, empirical models fail to reproduce the two‐dimensional shape of the shock in the simulation. This is because significant solar wind variability occurs on timescales less than the transit time of a single solar wind phase front over the curved shock surface. Empirical models must therefore be used with care when interpreting spacecraft data, especially when observations are made far from the Sun‐Earth line. Further analysis reveals a bias to higher shock speeds when measured by virtual spacecraft. This is attributed to the fact that the spacecraft only observes the shock when it is in motion. This must be accounted for when studying bow shock motion and variability with spacecraft data.
Phototunable Full‐Color Emission of Cellulose‐Based Dynamic Fluorescent Materials
Authors: Tian Weiguo , Zhang Jinming , Yu Jian , Wu Jin , Zhang Jun , He Jiasong , Wang Fosong 
Published: December 2017

AbstractAn iridescent chameleon‐like material that can change its colors under different circumstances is always desired in color‐on‐demand applications. Herein, a strategy based on trichromacy and the dynamically tunable fluorescence resonance energy transfer (FRET) process to design and prepare these chameleon‐like fluorescent materials is proposed. A set of trichromic (red, green, and blue), solid fluorescent materials are synthesized by covalently attaching spiropyran, fluorescein, and pyrene onto cellulose chains independently. After simply mixing them together, a full range of color is realized. The chameleon‐like nature of these materials is based on the dynamic tunable FRET process between donors (green and blue) and acceptors (red) in which the energy transfer efficiency can be finely tuned by irradiation. Ultimately, the reversible and nonlinear regulation of fluorescence properties, including color and intensity, is achieved on a timescale recognizable by the naked eye. Benefited by the excellent processability inherited from the cellulose derivatives, the as‐prepared materials are feasibly transformed into different forms. Particularly, a fluorescent ink with the complicated fluorescent input–output dependence suggests more than a proof‐of‐concept; indeed, it suggests a unique method of information encryption, security printing, and dynamic anticounterfeiting.
Yolk–Shell Nanostructures: Design, Synthesis, and Biomedical Applications
Authors: Lin Li‐Sen , Song Jibin , Yang Huang‐Hao , Chen Xiaoyuan 
Published: December 2017

AbstractYolk–shell nanostructures (YSNs) composed of a core within a hollow cavity surrounded by a porous outer shell have received tremendous research interest owing to their unique structural features, fascinating physicochemical properties, and widespread potential applications. Here, a comprehensive overview of the design, synthesis, and biomedical applications of YSNs is presented. The synthetic strategies toward YSNs are divided into four categories, including hard‐templating, soft‐templating, self‐templating, and multimethod combination synthesis. For the hard‐ or soft‐templating strategies, different types of rigid or vesicle templates are used for making YSNs. For the self‐templating strategy, a number of unconventional synthetic methods without additional templates are introduced. For the multimethod combination strategy, various methods are applied together to produce YSNs that cannot be obtained directly by only a single method. The biomedical applications of YSNs including biosensing, bioimaging, drug/gene delivery, and cancer therapy are discussed in detail. Moreover, the potential superiority of YSNs for these applications is also highlighted. Finally, some perspectives on the future research and development of YSNs are provided.
Blocking Energy‐Loss Pathways for Ideal Fluorescent Organic Light‐Emitting Diodes with Thermally Activated Delayed Fluorescent Sensitizers
Authors: Zhang Dongdong , Song Xiaozeng , Cai Minghan , Duan Lian 
Published: December 2017

AbstractOrganic light‐emitting diodes (OLEDs) based on thermally activated delayed fluorescence‐sensitized fluorescence (TSF) offer the possibility of attaining an ultimate high efficiency with low roll‐off utilizing noble‐metal free, easy‐to‐synthesize, pure organic fluorescent emitters. However, the performances of TSF‐OLEDs are still unsatisfactory. Here, TSF‐OLEDs with breakthrough efficiencies even at high brightnesses by suppressing the competitive deactivation processes, including direct charge recombination on conventional fluorescent dopants (CFDs) and Dexter energy transfer from the host to the CFDs, are demonstrated. On the one hand, electronically inert terminal‐substituents are introduced to protect the electronically active core of the CFDs; on the other hand, delicate device structures are designed to provide multiple energy‐funneling paths. As a result, unprecedentedly high maximum external quantum efficiency/power efficiency of 24%/71.4 lm W−1 in a green TSF‐OLED are demonstrated, which remain at 22.6%/52.3 lm W−1 even at a high luminance of 5000 cd m−2. The work unlocks the potential of TSF‐OLEDs, paving the way toward practical applications.
Genetically Engineered Liposome‐like Nanovesicles as Active Targeted Transport Platform
Authors: Zhang Pengfei , Zhang Long , Qin Zainen , Hua Suhang , Guo Zhide , Chu Chengchao , Lin Huirong , Zhang Yang , Li Wengang , Zhang Xianzhong , Chen Xiaoyuan , Liu Gang 
Published: December 2017

AbstractLigand‐targeted delivery of drug molecules to various types of tumor cells remains a major challenge in precision medicine. Inspired by the secretion process and natural cargo delivery functions of natural exosomes, biomimetic synthetic strategies are exploited to prepare biofunctionalized liposome‐like nanovesicles (BLNs) that can artificially display a wide variety of targeting protein/peptide ligands and directly encapsulate medical agents for enhanced drug delivery. Here, as a proof of concept, genetically engineered BLNs, which display human epidermal growth factor (hEGF) or anti‐HER2 Affibody as targeting moieties, are developed to, respectively, target two types of tumor cells. Notably, in comparison to synthetic liposomes covalently coupled with hEGF, it is demonstrated in this work that biosynthetically displayed hEGF ligands on BLNs possess higher biological activities and targeting capabilities. Additionally, treatments with doxorubicin‐loaded BLNs displaying Affibody ligands exhibit much better antitumor therapeutic outcomes than clinically approved liposomal doxorubicin (Doxil) in HER2‐overexpressing BT474 tumor xenograft models. These data suggest that BLN is suitable as a potent surrogate for conventional proteoliposomes or immunoliposomes as a result of excellent targeting capacities and facile production of BLNs.
Organocatalytic Synthesis of Oxazolines and Dihydrooxazines from Allyl‐Amides: Bypassing the Inherent Regioselectivity of the Cyclization
Authors: Theodorou Alexis , Triandafillidi Ierasia , Kokotos Christoforos G. 
Published: December 2017

AbstractA selective and efficient methodology for the construction of either oxazolines or dihydrooxazines from the corresponding allyl‐amides is reported. Bypassing the inherent selectivity of the cyclization and depending on the substitution pattern of the substrate, a selective epoxidation‐cyclization was developed leading to either the five‐membered or the six‐membered ring, upon simple and complementary reaction conditions. The cyclization products were obtained in good to excellent yields and high selectivities.magnified image
2D Co6Mo6C Nanosheets as Robust Hydrogen Evolution Reaction Electrocatalyst
Authors: He Chunyong , Tao Juzhou 
Published: December 2017

AbstractHydrogen production by electrochemical water splitting via nonprecious metal catalysts is still a great challenge due to sluggish kinetics and poor electrochemical durability toward hydrogen evolution reaction (HER). In this work, the fabrication of two dimensional (2D) bimetallic carbide nanosheets on graphene hybrid (Co6Mo6C NSs/G) is first reported, which exhibits excellent HER performance with a nearly zero onset overpotential, a small overpotential of 73 mV at current densities of 10 mA cm−2, a small Tafel slope of 43 mV dec−1, and an outstanding electrochemical durability. The density functional theoretical calculations suggest that the Gibbs free energy of hydrogen bonding of Co6Mo6C is −0.12 eV, which is very close to Pt (−0.09 eV).
Polylactic acid–agave fiber biocomposites produced by rotational molding: A comparative study with compression molding
Authors: Cisneros‐López Erick Omar , Pérez‐Fonseca Aida Alejandra , González‐García Yolanda , Ramírez‐Arreola Daniel Edén , González‐Núñez Rubén , Rodrigue Denis , Robledo‐Ortíz Jorge Ramón 
Published: December 2017

AbstractIn this work, the possibility to produce polylactic acid (PLA) and agave fiber biocomposites by dry‐blending and rotational molding was studied. The samples were also produced by compression molding to compare the effect of processing conditions on the biocomposites properties. In particular, the effect of fiber content (0–40 wt.%) on morphology, density, porosity, thermal (DSC) and mechanical properties (tension, flexion, impact and hardness) was studied. Also, a complete analysis of the internal air temperature profiles was performed to determine the thermal behavior of PLA during the rotational molding cycle. The results showed that rotomolded biocomposites were successfully produced but had higher porosity than compression molded ones due to the absence of pressure while forming. This led to different level of mechanical properties reduction as fiber content increases. Nevertheless, for compression‐molded biocomposites, crystallinity (30% at 30 wt.%), tensile modulus (14% at 30 wt.%) and impact strength (71% at 40 wt.%) improvements were obtained compared to neat PLA.
In Situ Synthesis of Vertical Standing Nanosized NiO Encapsulated in Graphene as Electrodes for High‐Performance Supercapacitors
Authors: Lin Jinghuang , Jia Henan , Liang Haoyan , Chen Shulin , Cai Yifei , Qi Junlei , Qu Chaoqun , Cao Jian , Fei Weidong , Feng Jicai 
Published: December 2017

AbstractNiO is a promising electrode material for supercapacitors. Herein, the novel vertically standing nanosized NiO encapsulated in graphene layers (G@NiO) are rationally designed and synthesized as nanosheet arrays. This unique vertical standing structure of G@NiO nanosheet arrays can enlarge the accessible surface area with electrolytes, and has the benefits of short ion diffusion path and good charge transport. Further, an interconnected graphene conductive network acts as binder to encapsulate the nanosized NiO particles as core–shell structure, which can promote the charge transport and maintain the structural stability. Consequently, the optimized G@NiO hybrid electrodes exhibit a remarkably enhanced specific capacity up to 1073 C g−1 and excellent cycling stability. This study provides a facial strategy to design and construct high‐performance metal oxides for energy storage.
The Impact of Molecular p‐Doping on Charge Transport in High‐Mobility Small‐Molecule/Polymer Blend Organic Transistors
Authors: Paterson Alexandra F. , Lin Yen‐Hung , Mottram Alexander D. , Fei Zhuping , Niazi Muhammad R. , Kirmani Ahmad R. , Amassian Aram , Solomeshch Olga , Tessler Nir , Heeney Martin , Anthopoulos Thomas D. 
Published: December 2017

AbstractMolecular doping is a powerful tool with the potential to resolve many of the issues currently preventing organic thin‐film transistor (OTFT) commercialization. However, the addition of dopant molecules into organic semiconductors often disrupts the host lattice, introducing defects and harming electrical transport. New dopant‐based systems that overcome practical utilization issues, while still reaping the electrical performance benefits, would therefore be extremely valuable. Here, the impact of p‐doping on the charge transport in blends consisting of the small‐molecule 2,7‐dioctyl[1]benzothieno[3,2‐b][1]benzothiophene (C8‐BTBT), the polymer indacenodithiophene‐benzothiadiazole (C16IDT‐BT), and the molecular dopant C60F48 is investigated. Electrical field‐effect measurements indicate that p‐doping not only enhances the average saturation mobility from 1.4 to 7.8 cm2 V−1 s−1 over 50 devices (maximum values from around 4 to 13 cm2 V−1 s−1), but also improves bias–stress stability, contact resistance, threshold voltage, and the overall device‐to‐device performance variation. Importantly, materials characterization using X‐ray diffraction, X‐ray photoemission spectroscopy, and ultraviolet photoemission spectroscopy, combined with charge transport modeling, reveal that effective doping is achieved without perturbing the microstructure of the polycrystalline semiconductor film. This work highlights the remarkable potential of ternary organic blends as a simple platform for OTFTs to achieve all the benefits of doping, with none of the drawbacks.
A Quintuple [6]Helicene with a Corannulene Core as a C5‐Symmetric Propeller‐Shaped π‐System
Authors: Kato Kenta , Segawa Yasutomo , Scott Lawrence T. , Itami Kenichiro 
Published: December 2017

AbstractThe synthesis and structural analysis of a quintuple [6]helicene with a corannulene core is reported. The compound was synthesized from corannulene in three steps including a five‐fold intramolecular direct arylation. X‐ray crystallographic analysis revealed a C5‐symmetric propeller‐shaped structure and one‐dimensional alignment in the solid state. The enantiomers of the quintuple [6]helicene were successfully separated by HPLC, and the chirality of the two fractions was identified by CD spectroscopy. A kinetic study yielded a racemization barrier of 34.2 kcal mol−1, which is slightly lower than that of pristine [6]helicene. DFT calculations indicate a rapid bowl‐to‐bowl inversion of the corannulene moiety and a step‐by‐step chiral inversion pathway for the five [6]helicene moieties.
Addition of H2 Across a Cobalt–Phosphorus Bond
Authors: Poitras Andrew M. , Knight Sadie E. , Bezpalko Mark W. , Foxman Bruce M. , Thomas Christine M. 
Published: December 2017

AbstractAddition of H2 across the cobalt–phosphorus bond of (PPP)CoPMe3 (3) is demonstrated, where PPP is a monoanionic diphosphine pincer ligand with a central N‐heterocyclic phosphido (NHP−) donor. The chlorophosphine CoII complex (PPClP)CoCl2 (2) can be generated through coordination of the chlorophosphine ligand (PPClP, 1) to CoCl2. Subsequent reduction of 2 with KC8 in the presence of PMe3 generates (PPP)CoPMe3 (3), in which both the phosphorus and cobalt centers have been reduced. The addition of 1 atm of H2 to complex 3 cleanly affords (PPHP)Co(H)PMe3 (4), in which H2 has ultimately been added across the metal–phosphorus bond. Complex 4 was characterized spectroscopically and using computational methods to predict its geometry.
Synthesis, spectroscopic, thermal analyses, biological activity and molecular docking studies on mixed ligand complexes derived from Schiff base ligands and 2,6‐pyridine dicarboxylic acid
Authors: Abd El‐Halim Hanan F. , Mohamed Gehad G. 
Published: December 2017

Two novel Schiff base ligands (La and Lb) were prepared from the condensation of quinoline 2‐aldehyde with 2‐aminopyridine (ligand La) and from the condensation of oxamide with furfural (ligand Lb). Mixed ligand complexes of the type M+2La/b Lc were prepared, where (La and Lb) the primary ligands and Lc was 2,6‐pyridinedicarboxylic acid as secondary ligand. Metal ions used were Fe(II), Co(II), Ni(II) and Zn(II) for mixed ligands La Lc and Fe(II), Co(II), Ni(II), Cu(II), Hg(II) and Zn(II) for LbLc mixed ligands. La and Lb Schiff base ligands were both characterized using elemental analyses, molar conductance, IR, 1H and 13C NMR. Mass spectra for Lb, [Zn(La)LcCl]Cl and [Cu(Lb)LcCl]Cl were also studied. ESR spectrum of the [Cu(Lb) LcCl]Cl complex was also recorded The metal complexes were synthesized and characterized using elemental analyses, spectroscopic (IR, 1H NMR, UV‐visible, diffused reflectance), molar conductance, magnetic moment and thermal studies. The IR and 1H NMR spectral data revealed that 2,6‐pyridinedicarboxalic acid ligand coordinated to the metal ions via pyridyl N and carboxylate O without proton displacement. In addition, the IR data showed that La and Lb ligands behaved as neutral bidentate ligands with N2 donation sites (quinoline N and azomethine N for La and two azomethine N for Lb). Based on spectroscopic studies, an octahedral geometry was proposed for the complexes. The thermal stability and degradation of the metal complexes were investigated by thermogravimetric analysis. The binding modes and affinities of La, Lb and Zn(II) complexes towards receptors of crystal structure of E. coli (PDB ID: 3 t88) and mutant oxidoreductase of breast cancer (PDB ID: 3 hb5) receptors were also studied.The antimicrobial activity against two species of Gram positive, Gram negative bacteria and fungi were tested for the Schiff base ligands, 2,6‐pyridinedicarboxylic acid and the mixed ligand complexes and revealed that the synthesized mixed ligand complexes exhibited higher antimicrobial activity than their free Schiff base ligands.
Nitrogen‐rich porous polyaminal network as a platform for iodine adsorption through physical and chemical interaction
Authors: Ren Yao‐Yao , Zhang Wuyong , Zhu Yunlong , Wang De‐Gao , Yu Guipeng , Kuang Gui‐Chao 
Published: December 2017

ABSTRACTA series of nitrogen‐rich porous polyaminal networks (PANs) with five different linkages were prepared through a facile route from cost‐effective starting materials. Each structural unit bears a different number of phenyl and pyrrolyl rings, which are found to be useful for iodine uptake through a physical adsorption mechanism. The PAN3 bearing the 4,4‐difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacene (BDP) units, which could adsorb iodine by both physical and chemical interaction, achieves an efficient iodine capacity up to 2.81 g/g. Significantly, these new nitrogen‐rich PANs might be useful for capture of other volatile compounds. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46106.
Thermal and antimicrobial evaluation of cotton functionalized with a chitosan–zeolite composite and microcapsules of phase‐change materials
Authors: Scacchetti Fabio A. P. , Pinto Eugénia , Soares Graça M. B. 
Published: December 2017

ABSTRACTAntimicrobial cotton was developed with silver zeolites (SZs). Three different application approaches for the cotton surface functionalization were followed: (1) SZ alone, (2) SZ combined with chitosan film, and (3) chitosan–zeolite (CS–SZ) composites previously synthesized by a gelation process with sodium tripolyphosphate. All finishes were applied to the textile materials through conventional pad–dry–cure processes, and the obtained results were then compared. The resulting materials were characterized with Fourier transform infrared spectroscopy, scanning electron microscopy with energy‐dispersive X‐ray spectroscopy, differential scanning calorimetry, IR thermography, and contact angle measurements, and the antimicrobial activity was evaluated. The results suggest that the application of CS–SZ should be recommended for the production of textiles with antibacterial properties because the materials showed activity against Escherichia coli, Staphylococcus aureus, Candida albicans, and Trichophyton rubrum. In addition, the finishing can be combined with the application of microcapsules of phase‐change materials to obtain textiles with thermoregulating properties. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46135.