bluuebunny/crossref_metadata_2025_split huggingface dataset:
Atomic-level characterization of free volume in the structure of Cu67Zr33 amorphous alloy
Authors: Itoh K , Yamada R , Saida J , Ikeda K , Otomo T 
Published: April 2021

Abstract
The structure of Cu67Zr33 amorphous alloy was investigated in terms of packing density and free volume by using neutron, x-ray diffraction and reverse Monte Carlo (RMC) modelling. The RMC model was analysed by a method of decomposing the three-dimensional atomic configuration into fundamental polyhedral units (termed as ‘holes’ referencing the Bernal’s works) of which faces are all triangles consisting of chemical bonds. Not only tetrahedral and octahedral holes but also other larger holes were identified. Moreover, the atomic packing fractions and free volumes in the respective polyhedral holes were evaluated with reference to those for the corresponding crystal structures. The results show that the distribution of free volumes for the larger holes can be described by the exponential function assuming that there are no energetic interactions between each other. On the other hand, the local structural fluctuations due to densely and loosely packed tetrahedral holes were observed, leading to the negative free volume spaces.
Determination of steep sidewall angle using polarization-sensitive asymmetric scattering
Authors: Dou Xiujie , Pereira Silvania F , Min Changjun , Zhang Yuquan , Meng Peiwen , Urbach H Paul , Yuan Xiaocong 
Published: April 2021

Abstract
The sidewall angle (SWA) of a nanostructure exerts influence on the performance of the nanostructure and plays an important role in processing nano-structural chips. It is still a great challenge to determine steep SWAs from far field measurements especially when the SWAs are close to 90°. Here, we propose a far-field detection system to determine steep SWA of a cliff-shape step structure on a silicon substrate by combining a split detector with a scanning method. The far-field radiation field is asymmetric due to the scattering of the step structure, and further numerical analysis demonstrates the reliability of this far-field measurement method. In the simulations, two key variables, i.e. the polarization state and the focus position of the incident laser beam, are considered to explore their impacts. By scanning over the structure laterally and longitudinally with both TE and TM polarizations, polarization effects on the far-field occur. These effects show higher sensitivity to steep SWA variation for TM polarization as compared to TE. Furthermore, with a comprehensive longitudinal scanning analysis for the TM polarization case, a feasible focus interval can be optimized to retrieve the steep SWA. As the proposed method is fast, highly sensitive and easy to implement, it provides a powerful approach to investigate the scattering behavior of nanostructures.
Metal-organic framework derived ultralow-loading platinum-copper catalyst: a highly active and durable bifunctional electrocatalyst for oxygen-reduction and evolution reactions
Authors: Parkash Anand 
Published: April 2021

Abstract
Electrocatalysts with high active oxygen reduction (ORR) and oxygen evolution reaction (OER) activities are key factors in renewable energy technologies. Unlike common strategies for adjusting the proportion of metal centers in a multi-metal organic framework (MOF), herein, we designed and synthesized bifunctional electrocatalysts using cetyltrimethylammonium bromide (CTAB)-capped ultra-low content platinum (Pt) (≤0.5 wt.% Pt) and copper (Cu) nanoparticles and doped on the surface of zinc-based MOF (Zn-MOF-74) and calcinated at 900 °C. According to the electrochemical activity, the Pt/Cu/NPC-900 exhibits superior catalytic activities towards both the ORR with the onset (E
0) and half-wave (E
1/2) potentials were 1.0 V and 0.89 V versus RHE, respectively, and OER (E
o = 1.48 V versus RHE and overpotential (η) = 0.265 V versus RHE) in an alkaline electrolyte at ambient temperature. Also, Pt/Cu/NPC-900 catalyzes through a 4- electron process and exhibits superior stability. Such insightful findings, as well as a newly developed approach, provides rational design and synthesis of an economical and efficient strategy for bifunctional electrocatalyst development.
Growth of black arsenic phosphorus thin films and its application for field-effect transistors
Authors: Izquierdo Nezhueyotl , Myers Jason C , Golani Prafful , De Los Santos Adonica , Seaton Nicholas C A , Koester Steven J , Campbell Stephen A 
Published: April 2021

Abstract
Black arsenic phosphorus single crystals were grown using a short-way transport technique resulting in crystals up to 12 × 110

μ
m

and ranging from 200 nm to 2

μ
m

thick. The reaction conditions require tin, tin (IV) iodide, gray arsenic, and red phosphorus placed in an evacuated quartz ampule and ramped up to a maximum temperature of 630 °C. The crystal structure and elemental composition were characterized using Raman spectroscopy, x-ray diffraction, and x-ray photoelectron spectroscopy, cross-sectional transmission microscopy, and electron backscatter diffraction. The data provides valuable insight into the growth mechanism. A previously developed b-P thin film growth technique can be adapted to b-AsP film growth with slight modifications to the reaction duration and reactant mass ratios. Devices fabricated from exfoliated bulk-b-AsP grown in the same reaction condition as the thin film growth process are characterized, showing an on-off current ratio of 102, a threshold voltage of −60 V, and a peak field-effect hole mobility of 23 cm2 V−1 s−1 at V
d = −0.9 V and V
g = −60 V.
Anatomy-aided deep learning for medical image segmentation: a review
Authors: Liu Lu , Wolterink Jelmer M , Brune Christoph , Veldhuis Raymond N J 
Published: April 2021

Abstract
Deep learning (DL) has become widely used for medical image segmentation in recent years. However, despite these advances, there are still problems for which DL-based segmentation fails. Recently, some DL approaches had a breakthrough by using anatomical information which is the crucial cue for manual segmentation. In this paper, we provide a review of anatomy-aided DL for medical image segmentation which covers systematically summarized anatomical information categories and corresponding representation methods. We address known and potentially solvable challenges in anatomy-aided DL and present a categorized methodology overview on using anatomical information with DL from over 70 papers. Finally, we discuss the strengths and limitations of the current anatomy-aided DL approaches and suggest potential future work.
Three-fluid model of the plasma–sheath region for a planar probe immersed in an active oxygen discharge. Validity of the Boltzmann relation
Authors: Morales Crespo R , Muñoz-Serrano E , Tejero-del-Caz A , Casado E 
Published: April 2021

Abstract
This paper studies the effect of the generation-loss processes in the plasma–sheath region close to a probe immersed in an oxygen discharge considering a three-fluid model for the charged species. A significant deviation from the Boltzmann relationship is obtained for the negative ion density when different values of the electron temperature, the negative ion temperature, the negative ion concentration, and the collision mean free path are considered.
Highly sensitive and stretchable strain sensor based on self-aligned and periodic cracking of wavy metal nanowire/elastomer composite film
Authors: Ha Sung-Hun , Kim Jong-Man 
Published: April 2021

Abstract
In this work, we present a new class of stretchable strain sensor employing a wavy metal nanowire (mNW)/elastomer composite film. Stretching-induced strain is predominantly concentrated in the valley regions of the wavy composite film following thermal annealing, and self-aligned and periodic mechanical cracks are induced by the strain concentration effect therein. The strain-dependent opening-and-closing process of the cracks supported by the mNW percolation network allows the sensor to exhibit large stretchability (160%) and high mechanosensitivity (gauge factor ≈874.1 at 110%–160% strain) simultaneously. Significant hysteresis is not observed, even when subjected to repeated stretching cycles. The wavy strain sensor is also demonstrated as a motion detector to recognize finger joint motions of a wooden hand model in real time.
Switching plasmonic resonance in multi-gap infrared metasurface absorber using vanadium dioxide patches
Authors: Negm Ayman , Bakr Mohamed , Howlader Matiar , Ali Shirook 
Published: April 2021

Abstract
Reconfigurable metasurface absorbers enable collecting or emitting radiation within selected frequency bands. It is thus necessary to decipher such behavior for many applications, including plasmonic energy harvesting, radiative cooling and thermal emitters. In this article, we propose a compact reconfigurable vanadium dioxide (VO2)-based metasurface absorber/emitter to demonstrate switching between dual and single-band absorption modes in the mid-infrared regime. The unit cell of the design employs a four-split gold circular ring resonator with gaps filled with VO2 patches. The phase-transition property of VO2 between semiconductor and metallic states is used to control the mode of operation of the metasurface absorber. When VO2 is in the semiconductor state, a dual-band absorption at 6 μm and 10.6 μm is obtained. When it attains a metallic state, the metasurface exhibits a single-band absorption at 8.25 μm. To achieve the maximum absorption efficiency in both single and dual-band modes, adaptive wind-driven optimization was employed as a global optimization technique. The proposed absorber provides polarization-independent behavior for both Transverse Electric and Transverse Magnetic polarizations. Moreover, the proposed design shows above 80% absorptance for incidence angle up to 45° for the dual-band mode, and up to 35° for the single-band mode. When operating the absorber as a tunable emitter, a switching of 79% in emissivity is achieved at 8.25 μm. These favorable findings may facilitate the development of important devices for temperature regulation, smart windows, and thermal imaging.
Constructing the weighting coefficients for the RBF-Hermite FD scheme under the multiquadric function on irregular meshes
Authors: Bin Jebreen Haifa , Tchier Fairouz 
Published: April 2021

Abstract
It is well known that the order of finite difference estimates on nonuniform grids reduce dramatically, particularly when higher order derivatives are required. This paper contributes how an optimization of the order of approximation formulas can be investigated and done on such grids for a sufficiently smooth function. To generalize the idea as well as get the optimized orders, the notion of radial basis function—Hermite finite difference (RBF–HFD) approach is used. The new weighting coefficients are worked out and proved to possess higher convergence rates. Several tests are also given to demonstrate the theoretical discussions.
Velocity-dependent J-factors for annihilation radiation from cosmological simulations
Authors: Board Erin , Bozorgnia Nassim , Strigari Louis E. , Grand Robert J.J. , Fattahi Azadeh , Frenk Carlos S. , Marinacci Federico , Navarro Julio F. , Oman Kyle A. 
Published: April 2021

Abstract
We determine the dark matter pair-wise relative velocity distribution in a set of Milky Way-like halos in the Auriga and APOSTLE simulations. Focusing on the smooth halo component, the relative velocity distribution is well-described by a Maxwell-Boltzmann distribution over nearly all radii in the halo. We explore the implications for velocity-dependent dark matter annihilation, focusing on four models which scale as different powers of the relative velocity: Sommerfeld, s-wave, p-wave, and d-wave models. We show that the J-factors scale as the moments of the relative velocity distribution, and that the halo-to-halo scatter is largest for d-wave, and smallest for Sommerfeld models. The J-factor is strongly correlated with the dark matter density in the halo, and is very weakly correlated with the velocity dispersion. This implies that if the dark matter density in the Milky Way can be robustly determined, one can accurately predict the dark matter annihilation signal, without the need to identify the dark matter velocity distribution in the Galaxy.
Reconstructing non-repeating radio pulses with Information Field Theory
Authors: Welling C. , Frank P. , Enßlin T. , Nelles A. 
Published: April 2021

Abstract
Particle showers in dielectric media produce radio signals
which are used for the detection of both ultra-high energy cosmic
rays and neutrinos with energies above a few PeV. The amplitude,
polarization, and spectrum of these short, broadband radio pulses
allow us to draw conclusions about the primary particles that caused
them, as well as the mechanics of shower development and radio
emission. However, confidently reconstructing the radio signals can
pose a challenge, as they are often obscured by background
noise. Information Field Theory offers a robust approach to this
challenge by using Bayesian inference to calculate the most likely
radio signal, given the recorded data. In this paper, we describe
the application of Information Field Theory to radio signals from
particle showers in both air and ice and demonstrate how accurately
pulse parameters can be obtained from noisy data.
Optical measurement of double-dot population using photon transmission via three coupled microresonators
Authors: Tsukanov A V , Kateev I Yu 
Published: April 2021

Abstract
A scheme for measuring the state of a charge qubit on a semiconductor single-electron double quantum dot (DQD) coupled to a photonic molecule (PM) consisting of three optical microresonators is proposed. The DQD that is the qubit plays the role of a nonlinear element whose electron state affects a PM response to an external laser field. Analysis of the spectroscopic response of the structure in the steady-state regime allows one to determine the state of the qubit. As an example, the spectrum of the PM formed by three GaAs microdisk resonators are calculated. The effect of various system parameters on the measuring contrast and the signal-to-noise ratio is studied. It is shown that this ratio can reach values of 15 000–20 000 for certain sets of parameters.
Spectral study of V565 Mon: probable FU Ori-like or chemically peculiar star
Authors: Andreasyan Hasmik 
Published: April 2021

Abstract
We present a detailed spectroscopic study of pre-main sequence star V565 Mon, which is the illuminating star of the Parsamian 17 cometary nebula. Observations were performed with the 2.6 m telescope in Byurakan Astrophysical Observatory on 2018 February 15. Radial velocities and equivalent widths of the most prominent lines of V565 Mon are presented. We build the spectral energy distribution and estimate the main parameters of the star, for example the obtained bolometric luminosity of V565 Mon is L

V565 ≈ 130 L
⊙. Considering all features of V565 Mon, we come to the conclusion that this young intermediate-mass star belongs to some intermediate class between T Tau and HAeBe stars. Very unusual for a young star is the presence of strong absorption Ba II lines in the spectrum. Possible explanations on this issue are discussed. Hence, we think that V565 Mon is a unique example, which can help to understand some open questions involved in the problem of nucleosynthesis in young stars.
A broad absorption line outflow associated with the broad emission line region in the quasar SDSS J075133.35+134548.3
Authors: Liu Bo , Zhou Hong-Yan , Shu Xin-Wen , Zhang Shao-Hua , Ji Tuo , Pan Xiang , Jiang Peng 
Published: April 2021

Abstract
We report on the discovery of unusual broad absorption lines (BALs) in the bright quasar SDSS J075133.35+134548.3 at z ∼ 1, using archival and newly obtained optical and NIR spectroscopic data. The BALs are detected reliably in He i* λ3889, He i* λ10830 and tentatively in Al iii, Mg ii. These BALs show complex velocity structures consisting of two major components: a high-velocity component (HV), with a blueshifted velocity range of Δv
HV ∼ −9300 − −3500 km s−1, which can be reliably detected in He i* λ10830, and tentatively in Al iii and Mg ii, whereas it is undetectable in He i* λ3889 and a low-velocity component (LV), with Δ v
LV ∼ −3500 − −1800 km s−1, is only detected in He i* and He i* λ10830. With the BALs from different ions, the HV outflowing gas can be constrained to have a density of n
H ∼1010.3–1011.4 cm−3, a column density of N
H ∼ 1021 cm−2 and an ionization parameter of U ∼10−1.83–10−1.72; inferring a distance of R
HV∼0.5 pc from the central continuum source with a monochromatic luminosity λ
Lλ
(5100) = 7.0×1045 erg s−1 at 5100 Å. This distance is remarkably similar to that of the normal broad line region (BLR) estimated from reverberation experiments, suggesting association of the BLR and the HV BAL outflowing gas. Interestingly, a blueshifted component is also detected in Al iii and Mg ii broad emission lines (BELs), and the Al iii/Mg ii of such a BEL component can be reproduced by the physical parameters inferred from the HV BAL gas. The LV BAL gas likely has a larger column density, a higher ionization level and hence a smaller distance than the HV BAL gas. Further spectroscopy with a high S/N ratio and broader wavelength coverage is needed to confirm this to shed new light on the possible connection between BALs and BELs.
A star-based method for precise wavelength calibration of the Chinese Space Station Telescope (CSST) slitless spectroscopic survey
Authors: Yuan Hai-Bo , Deng Ding-Shan , Sun Yang 
Published: April 2021

Abstract
The Chinese Space Station Telescope (CSST) spectroscopic survey aims to deliver high-quality low-resolution (R > 200) slitless spectra for hundreds of millions of targets down to a limiting magnitude of about 21 mag, distributed within a large survey area (17 500 deg2) and covering a wide wavelength range (255–1000 nm by three bands GU, GV, and GI). As slitless spectroscopy precludes the usage of wavelength calibration lamps, wavelength calibration is one of the most challenging issues in the reduction of slitless spectra, yet it plays a key role in measuring precise radial velocities of stars and redshifts of galaxies. In this work, we propose a star-based method that can monitor and correct for possible errors in the CSST wavelength calibration using normal scientific observations, taking advantage of the facts that (i) there are about ten million stars with reliable radial velocities now available thanks to spectroscopic surveys like LAMOST, (ii) the large field of view of CSST enables efficient observations of such stars in a short period of time, and (iii) radial velocities of such stars can be reliably measured using only a narrow segment of CSST spectra. We demonstrate that it is possible to achieve a wavelength calibration precision of a few km s−1 for the GU band, and about 10 to 20 km s−1 for the GV and GI bands, with only a few hundred velocity standard stars. Implementations of the method to other surveys are also discussed.
On the radial velocity calibrations in the LAMOST medium-resolution spectroscopic survey of nebulae
Authors: Ren Juan-Juan , Wu Hong , Wu Chao-Jian , Zhang Wei , Chen Jian-Jun , Hsia Chih-Hao , Yang Fan , Liu Chao , Shi Jian-Rong , Wu Yu-Zhong , Zhu Hui , Li Bin , Bai Zhong-Rui , Tian Hao , Hou Yong-Hui 
Published: April 2021

Abstract
Accurate radial velocity determinations of optical emission lines (i.e., [Nii] λλ 6548, 6584, Hα and [S ii] λλ 6717, 6731) are very important for investigating the kinematic and dynamic properties of nebulae. The second stage survey program of Large sky Area Multi-Object fiber Spectroscopic Telescope (LAMOST) has started a sub-survey of nebulae (MRS-N) which will spectroscopically observe the optical emission lines of a large sample of nebulae near the Galactic plane. Until now, 15 MRS-N plates have been observed from September 2017 to June 2019. Based on fitting the sky emission lines in the red band spectra of MRS-N, we investigate the precision of wavelength calibration and find there are systematic deviations of radial velocities (RVs) from ∼ 0.2 to 4 km s−1 for different plates. Especially for the plates obtained in March 2018, the systematic deviations of RVs can be as large as ∼ 4 km s−1, which then go down to ∼ 0.2 – 0.5 km s−1 at the end of 2018 and January 2019. An RV calibration function is proposed for these MRS-N plates, which can simultaneously and successfully calibrate the systematic deviations and improve the precision of RVs.
Investigation of the shortest period Am type eclipsing binary TYC 6408–989–1
Authors: Tian Xiao-Man 
Published: April 2021

Abstract
The first BV bands photometric observations and the low-resolution spectrum of the shortest period Am type eclipsing binary TYC 6408–989–1 have been obtained. The stellar atmospheric parameters of the primary star were obtained through the spectral fitting as follows: T
eff = 6990 ± 117 K, log g = 4.25 ± 0.26 cm s−2, [Fe/H] = −0.45 ± 0.03 dex. The original spectra obtained by European Southern Observatory (ESO) were processed with an IRAF package by us. Based on the ESO blue-violet spectra, TYC 6408–989–1 was concluded as a marginal Am (Am:) star with a spectral type of kA3hF1mA5 IV-V identified through the MKCLASS program. The observed light curves were analyzed through the Wilson-Devinney code. The final photometric solutions show that TYC 6408–989–1 is a marginal contact binary with a low mass ratio (q = 0.27). The temperature of the secondary component derived through the light curve analysis is significantly higher than main sequence stars. In addition, TYC 6408–989–1 is a poor thermal contact binary. The temperature differences between the two components is about 1800 K. TYC 6408–989–1 should be located in the oscillation stage predicted by the thermal relaxation oscillations theory (TRO) and will evolve into the shallow contact stage eventually. The very short period (less than one day), marginal Am peculiarity and quite large rotational velocity (v sin i ≃ 160 km s−1) make TYC 6408–989–1 become a challenge to the cut-off of rotation velocities and periods of Am stars. We have collected the well known eclipsing Am binaries with absolute parameters from the literature.
Adaptive scale model reconstruction for radio synthesis imaging
Authors: Zhang Li , Mi Li-Gong , Xu Long , Zhang Ming , Li Dan-Yang , Liu Xiang , Wang Feng , Xiao Yi-Fan , Wu Zhong-Zu 
Published: April 2021

Abstract
A sky model from CLEAN deconvolution is a particularly effective high dynamic range reconstruction in radio astronomy, which can effectively model the sky and remove the sidelobes of the point spread function (PSF) caused by incomplete sampling in the spatial frequency domain. Compared to scale-free and multi-scale sky models, adaptive-scale sky modeling, which can model both compact and diffuse features, has been proven to have better sky modeling capabilities in narrowband simulated data, especially for large-scale features in high-sensitivity observations which are exactly one of the challenges of data processing for the Square Kilometre Array (SKA). However, adaptive scale CLEAN algorithms have not been verified by real observation data and allow negative components in the model. In this paper, we propose an adaptive scale model algorithm with non-negative constraint and wideband imaging capacities, and it is applied to simulated SKA data and real observation data from the Karl G. Jansky Very Large Array (JVLA), an SKA precursor. Experiments show that the new algorithm can reconstruct more physical models with rich details. This work is a step forward for future SKA image reconstruction and developing SKA imaging pipelines.