bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impulsively Generated Wave Trains in Coronal Structures. I. Effects of Transverse Structuring on Sausage Waves in Pressureless Tubes
Authors: Yu Hui , Li Bo , Chen Shao-Xia , Xiong Ming , Guo Ming-Zhe 
Published: February 2017

Abstract
The behavior of the axial group speeds of trapped sausage modes plays an important role in determining impulsively generated wave trains, which have often been invoked to account for quasi-periodic signals with quasi-periods of the order of seconds in a considerable number of coronal structures. We conduct a comprehensive eigenmode analysis, both analytically and numerically, on the dispersive properties of sausage modes in pressureless tubes with three families of continuous radial density profiles. We find a rich variety of the dependence on the axial wavenumber k of the axial group speed

. Depending on the density contrast and profile steepness as well as on the detailed profile description, the

curves either possess or do not possess cutoff wavenumbers, and they can behave in either a monotonical or non-monotonical manner. With time-dependent simulations, we further show that this rich variety of the group speed characteristics heavily influences the temporal evolution and Morlet spectra of impulsively generated wave trains. In particular, the Morlet spectra can look substantially different from the “crazy tadpoles” found for the much-studied discontinuous density profiles. We conclude that it is necessary to re-examine available high-cadence data to look for the rich set of temporal and spectral features that can be employed to discriminate between the unknown forms of the density distributions transverse to coronal structures.
Spectroscopic Evidence of Alfvén Wave Damping in the Off-limb Solar Corona
Authors: Gupta G. R. 
Published: February 2017

Abstract
We investigate the off-limb active-region and quiet-Sun corona using spectroscopic data. The active region is clearly visible in several spectral lines formed in the temperature range of 1.1–2.8 MK. We derive the electron number density using the line ratio method, and the nonthermal velocity in the off-limb region up to the distance of 140 Mm. We compare density scale heights derived from several spectral line pairs with expected scale heights per the hydrostatic equilibrium model. Using several isolated and unblended spectral line profiles, we estimate nonthermal velocities in the active region and quiet Sun. Nonthermal velocities obtained from warm lines in the active region first show an increase and then later either a decrease or remain almost constant with height in the far off-limb region, whereas nonthermal velocities obtained from hot lines show consistent decrease. However, in the quiet-Sun region, nonthermal velocities obtained from various spectral lines show either a gradual decrease or remain almost constant with height. Using these obtained parameters, we further calculate Alfvén wave energy flux in both active and quiet-Sun regions. We find a significant decrease in wave energy fluxes with height, and hence provide evidence of Alfvén wave damping. Furthermore, we derive damping lengths of Alfvén waves in the both regions and find them to be in the range of 25–170 Mm. Different damping lengths obtained at different temperatures may be explained as either possible temperature-dependent damping or by measurements obtained in different coronal structures formed at different temperatures along the line of sight. Temperature-dependent damping may suggest some role of thermal conduction in the damping of Alfvén waves in the lower corona.
The Transfer of Resonance Line Polarization with Partial Frequency Redistribution in the General Hanle–Zeeman Regime
Authors: Ballester E. Alsina , Belluzzi L. , Bueno J. Trujillo 
Published: February 2017

Abstract
The spectral line polarization encodes a wealth of information about the thermal and magnetic properties of the solar atmosphere. Modeling the Stokes profiles of strong resonance lines is, however, a complex problem both from a theoretical and computational point of view, especially when partial frequency redistribution (PRD) effects need to be taken into account. In this work, we consider a two-level atom in the presence of magnetic fields of arbitrary intensity (Hanle–Zeeman regime) and orientation, both deterministic and micro-structured. Working within the framework of a rigorous PRD theoretical approach, we have developed a numerical code that solves the full non-LTE radiative transfer problem for polarized radiation, in one-dimensional models of the solar atmosphere, accounting for the combined action of the Hanle and Zeeman effects, as well as for PRD phenomena. After briefly discussing the relevant equations, we describe the iterative method of solution of the problem and the numerical tools that we have developed and implemented. We finally present some illustrative applications to two resonance lines that form at different heights in the solar atmosphere, and provide a detailed physical interpretation of the calculated Stokes profiles. We find that magneto-optical effects have a strong impact on the linear polarization signals that PRD effects produce in the wings of strong resonance lines. We also show that the weak-field approximation has to be used with caution when PRD effects are considered.
Deconstrucción del “buen profesor”. Análisis de las características formales y no formales de la docencia universitaria
Authors: Casero-Martínez, Antonio Antonio 
Published: February 2017

Antecedentes: la evaluación de la calidad del profesorado universitario, desde el punto de vista del alumnado, se ha centrado principalmente en los aspectos más formales del ejercicio docente, desatendiendo así otros factores de tipo personal. Objetivo: identificar y analizar las cargas de cada uno de los distintos factores que conforman la idea de la buena docencia según el alumnado. Es decir, detectar la ecuación que da lugar al esquema mental de “buen profesor” o “buena profesora”. Método: encuesta transversal, elaborada a partir de los resultados de revisiones e investigaciones propias que permitieron conocer la identidad de los distintos factores implicados en la evaluación de la docencia por parte del alumnado. La muestra es de 885 alumnos de la Universitat de les Illes Balears, obtenidos mediante un procedimiento de muestreo mixto y polietápico. Resultados: la solución factorial de cuatro elementos, que en orden de mayor a menor varianza explicada son: cualidades personales, competencia formal, cumplimiento, y materia. El análisis de regresión determina que cada uno de los 4 factores presenta un efecto estadísticamente significativo sobre la consideración de buen docente, donde el primero y el segundo son, en suma, responsables del 93% de toda la varianza explicada por el modelo. Conclusiones: el gran peso que las características no formales presentan en la ecuación resultante abre la discusión en torno a la importancia de las cualidades personales del profesorado como elementos que pueden estar modulando, más allá de la satisfacción del alumnado, el propio proceso enseñanza-aprendizaje.
The Triply Deprotonated Acetonitrile Anion CCN3− Stabilized in a Solid
Authors: Jach Franziska , Brückner Stephan Ingmar , Ovchinnikov Alexander , Isaeva Anna , Bobnar Matej , Groh Matthias Friedrich , Brunner Eike , Höhn Peter , Ruck Michael 
Published: February 2017

AbstractThe unprecedented, fully deprotonated form of acetonitrile, the acetonitriletriide anion CCN3−, is experimentally realized for the first time in the stabilizing bulk host framework of the Ba5[TaN4][C2N] nitridometalate via a one‐pot synthesis from the elements under moderate conditions (920 K). The molecular structure of this long‐sought acetonitrile derivative is confirmed by X‐ray diffraction, as well as NMR, IR, and Raman spectroscopy. The anion is isoelectronic to the CO2 molecule, and, in contrast to acetonitrile (H3C−C≡N), the electron pairs are shifted towards two double bonds, that is, [C=C=N]3−.
Mapping‐Out Catalytic Processes in a Metal–Organic Framework with Single‐Crystal X‐ray Crystallography
Authors: Burgun Alexandre , Coghlan Campbell J. , Huang David M. , Chen Wenqian , Horike Satoshi , Kitagawa Susumu , Alvino Jason F. , Metha Gregory F. , Sumby Christopher J. , Doonan Christian J. 
Published: February 2017

AbstractSingle‐crystal X‐ray crystallography is employed to characterize the reaction species of a full catalytic carbonylation cycle within a MnII‐based metal–organic framework (MOF) material. The structural insights explain why the Rh metalated MOF is catalytically competent toward the carbonylation of MeBr but only affords stoichiometric turn‐over in the case of MeI. This work highlights the capability of MOFs to act as platform materials for studying single‐site catalysis in heterogeneous systems.
Batch and Fed‐Batch Degradation of Enrofloxacin by the Fenton Process
Authors: Frade Verônica M. F. , Converti Attilio , Arni Saleh Al , Silva Milena F. , Palma Mauri S. A. 
Published: February 2017

AbstractEnrofloxacin is a synthetic second‐generation fluoroquinolone used as an antimicrobial agent exclusively in veterinary medicine. To simulate the treatment of wastewater contaminated by enrofloxacin, four‐day long fed‐batch runs were carried out according to the Fenton process with an enrofloxacin solution as model, to which hydrogen peroxide and ferrous ion were added twice a day. The residual enrofloxacin concentration was practically coincident to that detected at the end of the batch tests. Hydrogen peroxide was almost completely consumed after each feeding period, while the total organic carbon (TOC) concentration decreased gradually within three days, corresponding to a reduction > 58 %. From the third day on, the TOC falling rate was quite low. A yellow sludge settled due to the precipitation of both Fe(OH)3 and a complex formed by ferric ion with adsorbed enrofloxacin and/or its oxidation products.
Introgressive hybridization and morphological transgression in the contact zone between two MediterraneanSoleaspecies
Authors: Souissi Ahmed , Gagnaire Pierre‐Alexandre , Bonhomme François , Bahri‐Sfar Lilia 
Published: February 2017

AbstractHybrid zones provide natural experiments where new combinations of genotypes and phenotypes are produced. Studying the reshuffling of genotypes and remodeling of phenotypes in these zones is of particular interest to document the building of reproductive isolation and the possible emergence of transgressive phenotypes that can be a source of evolutionary novelties. Here, we specifically investigate the morphological variation patterns associated with introgressive hybridization between two species of sole,Solea senegalensisandSolea aegyptiaca. The relationship between genetic composition at nuclear loci and individual body shape variation was studied in four populations sampled across the hybrid zone located in northern Tunisia. A strong correlation between genetic and phenotypic variation was observed among all individuals but not within populations, including the two most admixed ones. Morphological convergence between parental species was observed close to the contact zone. Nevertheless, the samples taken closest to the hybrid zone also displayed deviant segregation of genotypes and phenotypes, as well as transgressive phenotypes. In these samples, deviant body shape variation could be partly attributed to a reduced condition index, and the distorted genetic composition was most likely due to missing allelic combinations. These results were interpreted as an indication of hybrid breakdown, which likely contributes to postmating reproductive isolation between the two species.
Is parental competitive ability in winter negatively affected by previous springs’ family size?
Authors: Fokkema Rienk W. , Ubels Richard , Tinbergen Joost M. 
Published: February 2017

AbstractReproductive behavior cannot be understood without taking the local level of competition into account. Experimental work in great tits (Parus major) showed that (1) a survival cost of reproduction was paid in environments with high levels of competition during the winter period and (2) experimentally manipulated family size negatively affected the ability of parents to compete for preferred breeding boxes in the next spring. The fact that survival was affected in winter suggests that the competitive ability of parents in winter may also be affected by previous reproductive effort. In this study, we aim to investigate whether (1) such carryover effects of family size on the ability of parents to compete for resources in the winter period occurred and (2) this could explain the occurrence of a survival cost of reproduction under increased competition. During two study years, we manipulated the size of in total 168 great tit broods. Next, in winter, we induced competition among the parents by drastically reducing the availability of roosting boxes in their local environment for one week. Contrary to our expectation, we found no negative effect of family size manipulation on the probability of parents to obtain a roosting box. In line with previous work, we did find that a survival cost of reproduction was paid only in plots in which competition for roosting boxes was shortly increased. Our findings thus add to the scarce experimental evidence that survival cost of reproduction are paid under higher levels of local competition but this could not be linked to a reduced competitive ability of parents in winter.
Probabilistic‐based secrecy rate maximisation for MIMOME wiretap channels: Towards novel convexification procedures
Authors: Zamanipour Makan 
Published: February 2017

AbstractThe paper first provides a general overview on the existing probabilistic‐driven methods aimed at convexifying the secrecy rate maximisation problem. Challenges and requirements of the procedures are fully taken into consideration for multiinput multioutput multiantenna eavesdropper wiretap channels. The problem constrained by an outage probability for the pure Ergodic capacity (perfect secrecy defined by Shannon) is analytically solved. Such analytical solution is performed robustly, something that originates principally from our imperfect statistical knowledge of the wiretap channel at the transmitter. Then, solely concentrating on McDiarmid inequality, we also extend our previous work to propose 2 new approaches. The bounds of our represented schemes are obviously accurate, tight, and achievable, something that effectively guarantee the system to overcome the probable challenges, eg, correlation in multiinput multioutput antenna arrays. Furthermore, the procedures are straightforwardly compared with each other from standpoint of complexity. Results are technically conducted to assure us about the proposed methods' merits, merely defining the significantly more favourable asymptotic bounds and the less resultant complexities. In particular, our proposed approaches sensibly outperform all the procedures, per se, something that can be accordingly assigned for other ergodic equilibria.
A new fifth order finite difference WENO scheme for Hamilton‐Jacobi equations
Authors: Zhu Jun , Qiu Jianxian 
Published: February 2017

AbstractIn this continuing paper of (Zhu and Qiu, J Comput Phys 318 (2016), 110–121), a new fifth order finite difference weighted essentially non‐oscillatory (WENO) scheme is designed to approximate the viscosity numerical solution of the Hamilton‐Jacobi equations. This new WENO scheme uses the same numbers of spatial nodes as the classical fifth order WENO scheme which is proposed by Jiang and Peng (SIAM J Sci Comput 21 (2000), 2126–2143), and could get less absolute truncation errors and obtain the same order of accuracy in smooth region simultaneously avoiding spurious oscillations nearby discontinuities. Such new WENO scheme is a convex combination of a fourth degree accurate polynomial and two linear polynomials in a WENO type fashion in the spatial reconstruction procedures. The linear weights of three polynomials are artificially set to be any random positive constants with a minor restriction and the new nonlinear weights are proposed for the sake of keeping the accuracy of the scheme in smooth region, avoiding spurious oscillations and keeping sharp discontinuous transitions in nonsmooth region simultaneously. The main advantages of such new WENO scheme comparing with the classical WENO scheme proposed by Jiang and Peng (SIAM J Sci Comput 21 (2000), 2126–2143) are its efficiency, robustness and easy implementation to higher dimensions. Extensive numerical tests are performed to illustrate the capability of the new fifth WENO scheme. © 2016 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 33: 1095–1113, 2017
Concepts for external light trapping and its utilization in colored and image displaying photovoltaic modules
Authors: van Dijk Lourens , van de Groep Jorik , Veldhuizen Leon W. , Di Vece Marcel , Schropp Ruud E. I. 
Published: February 2017

AbstractThe reflection of incident sunlight prevents photovoltaic modules from reaching their full energy conversion potential. Recently, we demonstrated significant absorption enhancement in various solar cells by external light trapping, using 3D‐printed and milled light traps. In order to facilitate direct module integration, we introduce an external light trapping design concept tackling the reflection issues at the module level. In this module design, a lens array on the module cover glass funnels the incident sunlight through small apertures in a reflective coating at the backside of the cover glass. This adapted cover glass can be applied on a conventional module design. The reflector and the solar cells together form an optical cavity, in which most reflected light is recycled by directing the reflected light back to the solar cell. A unique feature of this light trapping module is its capability to simultaneously recycle the broadband reflection from the metal front grid, the front interfaces, the reflective backside of the cell, and the white back sheet. Moreover, it allows separate integration and contacting of low and high bandgap solar cells for highly efficient hybrid tandem modules that have no current matching related losses. We show five module designs for improved light management combined with additional features such as color and image display. We discuss the optimal harvesting of the diffuse and direct component of the sunlight. The outlook of highly efficient, colored, and even image displaying modules makes this technology an interesting candidate for a new class of photovoltaic modules. Copyright © 2017 John Wiley & Sons, Ltd.
Benzimidazole‐indole‐chalcone connected methacrylate‐based side chain D‐π‐A polymer and its application in organic photovoltaics
Authors: Selvam Ramasamy , Subramanian Kathavarayan 
Published: February 2017

ABSTRACTHerein, we report four metal‐free organic polymethacrylates (In‐In‐BzI)PMA, (Ac‐In‐BzI)PMA, (TPA‐In‐BzI)PMA, and (Py‐In‐BzI)PMA with pendant chromophores donor‐π‐conjugated‐acceptor (D‐π‐A) molecular framework as photosensitizers for dye‐sensitized solar cells (DSSCs). In which the donor‐acceptor units are attached by an indole‐chalcone extending side chain to inhibit back electron transfer and charge recombination; the π‐linker component contains varied chalcone‐based substituents to enhance the sunlight‐harvesting ability of the solar device. Photon‐current cells based on the DSSC format were fabricated using the polymers as sensitizers. The DSSC device assembled using (TPA‐In‐BzI)PMA exhibits a considerably better IPCE peak and J–V response, with an overall power conversion efficiency of 3.70% under the illumination of AM 1.5G (100 mW cm–2). © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 997–1007
High‐density polyethylene/expanded graphite nanocomposites produced by polymerization‐filling technique using an industrial heterogeneous catalyst
Authors: da Cruz Kátia Z. C , Casagrande Adriana C. A. , Casagrande Osvaldo L. 
Published: February 2017

ABSTRACTHigh‐density polyethylene nanocomposites with different expanded graphite (EG) contents (0.34–1.80 wt %) were prepared by polymerization‐filling technique using an industrial heterogeneous catalyst (cat K), and characterized using a range techniques: melting flow index (MFI), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and transmission electron microscopy (TEM). The MFI data showed that EG acts as a plasticizer decreasing melt viscosity in comparison to neat HDPE produced exclusively by cat K. DSC results showed that EG nucleated the HDPE crystallization as established by the increased crystallization temperature, and the degree of crystallinity. HDPE/EG nanocomposites displayed a significant improvement in the flexural (increased from 1458 to 1831 MPa), and storage modulus (increased from 122 to 1627 MPa) at only 1.80 wt % EG content. TEM images confirmed a homogeneous distribution of EG into the polymer matrix with the presence of dispersed, intercalated and aggregated EG nanofillers. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 55, 1260–1267
Classical information transfer between distant quantum dots using individual electrons in fast moving quantum dots
Authors: Hermelin Sylvain , Bertrand Benoit , Takada Shintaro , Yamamoto Michihisa , Tarucha Seigo , Ludwig Arne , Wieck Andreas D. , Bäuerle Christopher , Meunier Tristan 
Published: February 2017

AbstractOver the past two decades, lateral quantum dots have permitted a tremendous advancement in the manipulation of individual electrons. In order to have a complete toolbox for electronics at the single electron level, local manipulation in a quantum dot needs to be associated with the controlled transport of individual electrons. Here, we review results on the transfer of individual electrons and their spin degree of freedom between distant lateral quantum dots. The electron is transported in a surface acoustic wave‐generated moving quantum dot, with an efficiency of 92%. Furthermore, we will review recent results showing that classical spin information/magnetization can be partially transferred using this method. The fidelity was proven to be limited by the current sample design and implementation, and no fundamental limitation was met. This transfer capability opens new avenues in spin‐based quantum information processing and in the implementation of quantum optics experiments with flying electrons.