bluuebunny/crossref_metadata_2025_split huggingface dataset:
Theoretical limit of how small we can make MoS2 transistor channels
Authors: Lü Haichao , Zhang Yang , Liu Xiaojie , Wang Yin , Zhang Qiang , Yin Haitao 
Published: November 2021

Abstract
As the size of electronic devices is reduced below 3 nm, contact resistance and tunnel leakage current have become crucial factors affecting device performance. The 2D material MoS2 is a potential semiconductor to substitute conventional silicon. In this work, the density functional theory combined with the non-equilibrium Green’s function was used to simulate the transport properties of 2H semiconductor phase MoS2 connected to 1T metal phase MoS2 lead. It is found that when the channel length is greater than or equal to 2.736 nm, the leakage current can be negligible, marking this length as miniaturization limit for a conventional transistors or diodes. When the channel length is smaller than 2.736 nm, the transport is dominated by the direct tunneling. The junctions can be used to design the devices based on the tunneling effect.
Efficient energy-based orthogonal matching pursuit algorithm for multiple sound source localization with unknown source count
Authors: Tang Rongjiang , Zuo Yingxiang , Liu Weiya , Zheng Weiguang , Tang Liguo , Xiao Fei 
Published: November 2021

Abstract
In this paper, we propose a compressed sensing (CS) sound source localization algorithm based on signal energy to solve the problem of stopping the iteration condition of the orthogonal matching pursuit (OMP) reconstruction algorithm in CS. The orthogonal matching tracking algorithm needs to stop iteration according to the number of sound sources or the change of residual. Generally, the number of sound sources cannot be known in advance, and the residual often leads to unnecessary calculation. Because the sound source is sparsely distributed in space, and its energy is concentrated and higher than that of the environmental noise, the comparison of the signal energy at different positions in each iteration reconstruction signal is used to determine whether the new sound source is added in this iteration. At the same time, the block sparsity is introduced by using multiple frequency points to avoid the problem of different iteration times for different frequency points in the same frame caused by the uneven energy distribution in the signal frequency domain. Simulation and experimental results show that the proposed algorithm retains the advantages of the orthogonal matching tracking sound source localization algorithm, and can complete the iteration well. Under the premise of not knowing the number of sound sources, the maximum error between the number of iterations and the set number of sound sources is 0.31. The experimental results show that the proposed algorithm has good positioning accuracy and has certain anti-reverberation capability. Compared with other OMP algorithms, the proposed algorithm has better iterative ability and stability. This work is helpful in promoting the development of multiple sound source localization.
Liquid-dependent impedance induced by vapor condensation and percolation in nanoparticle film
Authors: Kano Shinya , Mekaru Harutaka 
Published: November 2021

Abstract
A liquid-dependent impedance is observed by vapor condensation and percolation in the void space between nanoparticles. Under the Laplace pressure, vapor is effectively condensed into liquid to fill the nanoscale voids in an as-deposited nanoparticle film. Specifically, the transient impedance of the nanoparticle film in organic vapor is dependent on the vapor pressure and the conductivity of the condensed liquid. The response follows a power law that can be explained by the classical percolation theory. The condensed vapor gradually percolates into the void space among nanoparticles. A schematic is proposed to describe the vapor condensation and percolation dynamics among the nanoparticles. These findings offer insights into the behavior of vapor adsorbates in nanomaterial assemblies that contain void space.
Conductive bimetal organic framework nanorods decorated with highly dispersed Co3O4 nanoparticles as bi-functional electrocatalyst
Authors: Duan Yaxin , Liu Haitao , Zhang Huabing , Ke Shaojie , Wang Shuaize , Dou Meiling , Wang Feng 
Published: November 2021

Abstract
The poor electronic conductivity and low intrinsic electrocatalytic activity of metal organic frameworks (MOFs) greatly limit their direct application in electrocatalytic reactions. Herein, we report a conductive two-dimensional π–d conjugated Ni and Co bimetal organic framework (MOF)—NiCo-(2,3,6,7,10,11-hexaiminotriphenylene) (NiCo-HITP) nanorods decorated with highly dispersed Co3O4 nanoparticles (NPs) as a promising bi-functional electrocatalyst towards oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) through an effective and facile strategy by modifying the rod-shaped -Ni3HITP2 crystals using cobalt ions. The triggered electrocatalytic activity of the resulting MOF-based materials was achieved by increasing the electrical conductivity (7.23 S cm−1) originated from Ni3HITP2 substrate and also by creating the cooperative catalysis sites of Co–N
x
and Co3O4 NPs. Optimized syntheses show a promising ORR activity with a high half-wave potential (0.77 V) and also a significantly improved OER activity compared with pure Ni3HITP2 in alkaline electrolyte. Furthermore, a rechargeable Zn–air battery using the as-prepared material as air-cathode also shows a high power density (143.1 mW cm−2)—even comparable to a commercial Pt/C-RuO2-based battery. This methodology offers a new prospect in the design and synthesis of non-carbonized MOF bi-functional electrocatalysts for efficient catalysis towards ORR and OER.
A novel single-lead handheld atrial fibrillation detection system
Authors: Li Ying , Li Jianqing , Yang Chenxi , Xing Yantao , Liu Chengyu 
Published: November 2021

Abstract

Objective. The single-lead handheld atrial fibrillation (AF) detection device is suitable for daily monitoring or early screening of AF in the hospital. However, the signal quality and the reliability of AF detection algorithm still need to be improved. This study proposed a novel AF detection system with a user-friendly interaction and a lightweight and accurate AF detection algorithm. Approach. The system consisted of a single-lead handheld electrocardiogram device with a novel appearance like a gaming handle and a smartphone terminal embedded with AF detection. After feature optimization, the rule-based multi-feature AF detection algorithm had relatively good AF detection ability. Three types of experiments were designed to test the performance of the system. (1) Test the accuracy and time/memory cost of the AF detection algorithm. (2) Compare the proposed device with the standard device Shimmer. (3) Use the simulator to test the effectiveness of the system. Main results. The percentage of differences of successive RR intervals larger than 50 ms (PNN50), minimum value of RR intervals (minRR), and coefficient of sample entropy (COSEn) were features chosen for AF detection. (1) The sensitivity, specificity, and accuracy were 96.00%, 99.75%, 97.88% on the MIT-BIH AF database, and 98.50%, 94.50%, 96.50% on the clinical database we founded. The time/memory cost of the proposed algorithm was much smaller than that of support vector machine. (2) The mean correlation coefficient of RR was 0.9950, indicating a high degree of consistency. (3) This system showed the effectiveness of AF detection. Significance. The proposed single-lead handheld AF detection system is demonstrated to be accurate, lightweight, consistent with the standard device, and efficient for AF detection.
A machine learning approach for predicting the electro-mechanical impedance data of blended RC structures subjected to chloride laden environment
Authors: Bansal Tushar , Talakokula Visalakshi , Sathujoda Prabhakar 
Published: November 2021

Abstract
The application of the electro-mechanical impedance (EMI) technique using piezo sensors for structural health monitoring (SHM) is based on baseline/healthy signature data, which poses serious limitations when it needs to be applied to existing structures. Therefore, the present research utilizes autoregressive integrated moving average (ARIMA), an effective time series forecasting machine learning algorithm to predict the baseline/healthy EMI data and futuristic data of reinforced concrete corroded specimens. The EMI data from the ARIMA model is validated with the experimental data, and the results obtained prove that the model could be utilized to predict the baseline and forecast the EMI corrosion data effectively. These results will aid the researchers to predict the baseline data for the existing structures and utilize the EMI technique for SHM purposes.
Broadband highly efficient nonlinear optical processes in on-chip integrated lithium niobate microdisk resonators of Q-factor above 108
Authors: Gao Renhong , Zhang Haisu , Bo Fang , Fang Wei , Hao Zhenzhong , Yao Ni , Lin Jintian , Guan Jianglin , Deng Li , Wang Min , Qiao Lingling , Cheng Ya 
Published: November 2021

Abstract
Microresonators of ultrahigh quality (Q) factors represent a crucial type of photonic devices aiming at ultra-high spectral resolution, ultra-high sensitivity to the environmental perturbations, and efficient nonlinear wavelength conversions at low threshold pump powers. Lithium niobate on insulator (LNOI) microdisks of high Q factors are particularly attractive due to its large second-order nonlinear coefficient and strong electro-optic property. In this letter, we break through the long standing bottleneck in achieving the Q factors of LNOI microresonators beyond 108, which approaches the intrinsic material absorption limit of lithium niobate (LN). The ultra-high Q factors give rise to a rich family of nonlinear optical phenomena from optical parametric oscillation (OPO) to harmonics generation with unprecedented characteristics including ultra-low pump threshold, high wavelength conversion efficiency, and ultra-broad operation bandwidth. Specifically, the threshold of OPO is measured to be only 19.6 μW, and the absolute conversion efficiency observed in the second harmonic generation reaches 23%. The record-breaking performances of the on-chip ultra-high Q LNOI microresonators will have profound implication for both photonic research and industry.
Neutron/gamma radiation shielding characteristics and physical properties of (97.3−x)Pb−xCd–2.7Ag alloys for nuclear radiation applications
Authors: Reda A M , El-Daly A A , Eid E A 
Published: November 2021

Abstract
In this work, the shielding performance of (97.3–x)Pb–xCd–2.7Ag (x = 10, 18, and 30) ternary alloys against neutrons and gamma rays has been investigated. The microstructure, thermal and mechanical properties of the ternary alloys were examined. The total mass attenuation coefficients,

μ
/
ρ
,

for prepared alloys were determined at 662, 1173, and 1332 keV photon energies using NaI (Tl) scintillation detector. The theoretical values of

μ
/
ρ

were calculated using WinXCom program depending on the mixture rule. The estimated values were compared with the measured values for all investigated alloys. Atomic cross-section, σ
a, electronic cross-section, σ
e, effective atomic number, Z

eff
, effective electron number, N

eff
, and GP fitting parameters (b, c, a, Xk, and d) were determined. The exposure buildup factor, EBF, have been also calculated. Fast neutron attenuation for the prepared samples have been investigated via the macroscopic effective removal cross-section (

∑

R

) calculation. Also, thermal neutron attenuation has been evaluated via neutron scattering calculator. The results show that the alloys containing 10 and 30% Cd compromise between superior tensile strength and Young modulus, while the pasty range, heat of fusion and ductility decreased with increasing Cd content. Moreover, the prepared ternary alloys have a high attenuation ability for gamma rays as the standard Pb. The increase of Cd ratio also significantly enhances the thermal neutron attenuation by amazing way along with the increase in the attenuation rate of fast neutrons.
Effect of ion beam current on dust charge fluctuations and ion-acoustic waves in electronegative dusty plasmas
Authors: Basnet Suresh , Maskey Anish , Deuja Atit , Khanal Raju 
Published: November 2021

Abstract
The effects of ion beam current associated with the streaming positive ions on the dust charge fluctuations and ion acoustic wave propagation in quiescent electronegative dusty plasma have been investigated using fluid theory. The dust charging phenomenon and unstable mode of ion waves are modified for two streaming conditions of positive ions which are extended and graphically illustrated. The dependencies of the growing and damping rate of ion waves on dust density and the size of dust grains are studied. The evolution of dust surface potential is found in the negative domain with the increase in concentration of negative ions and the instability rate for ion wave decreases. Furthermore, it is shown that the dust surface potential shifts into positive domain as the electrons are significantly depleted (and the plasma becomes ion-ion plasma) from the electronegative plasma and thus ion waves exhibit a damping phenomenon.
Particle scattering by rotating trapped quantum gases at finite temperature
Authors: Das Samir , Biswas Shyamal 
Published: November 2021

Abstract
We have analytically explored the quantum phenomena of particle scattering by rotating trapped quantum gases of electrically neutral bosons and fermions for the short-ranged Fermi-Huang interactions between the incident particle and the scatterers. We have predicted differential scattering cross-sections and their temperature and angular velocity dependencies in this regard, in particular, for an ideal Bose gas in a rotating harmonic trap, an ideal Fermi gas in a rotating harmonic trap, and a weakly interacting Bose gas in a slow rotating harmonic trap. We have theoretically probed the lattice-pattern of the vortices in a rapidly rotating strongly interacting Bose–Einstein condensate by the particle scattering method. We also have obtained de Haas-van Alphen-like oscillations in the differential scattering cross-section for an ideal ultracold Fermi gas in a rotating harmonic trap. Our predictions on the differential scattering cross-sections can be tested within the present-day experimental setups.
Spinning guest fields during inflation: leftover signatures
Authors: Dimastrogiovanni Emanuela , Fasiello Matteo , Gümrükçüoğlu A. Emir 
Published: November 2021

Abstract
We consider the possibility of extra spinning particles
during inflation, focussing on the spin-2 case. Our analysis relies
on the well-known fully non-linear formulation of interacting spin-2
theories. We explore the parameter space of the corresponding
inflationary Lagrangian and identify regions therein exhibiting
signatures within reach of upcoming CMB probes. We provide a
thorough study of the early and late-time dynamics ensuring that
stability conditions are met throughout the cosmic evolution. We
characterise in particular the gravitational wave spectrum and
three-point function finding a local-type non-Gaussianity whose
amplitude may be within the sensitivity range of both the LiteBIRD
and CMB-S4 experiments.
Gravitational wave propagation beyond general relativity: waveform distortions and echoes
Authors: Ezquiaga Jose Maria , Hu Wayne , Lagos Macarena , Lin Meng-Xiang 
Published: November 2021

Abstract
We study the cosmological propagation of gravitational waves
(GWs) beyond general relativity (GR) across homogeneous and
isotropic backgrounds. We consider scenarios in which GWs interact
with an additional tensor field and use a parametrized
phenomenological approach that generically describes their coupled
equations of motion. We analyze four distinct classes of derivative
and non-derivative interactions: mass, friction, velocity, and
chiral. We apply the WKB formalism to account for the cosmological
evolution and obtain analytical solutions to these equations. We
corroborate these results by analyzing numerically the propagation
of a toy GW signal. We then proceed to use the analytical results to
study the modified propagation of realistic GWs from merging compact
binaries, assuming that the GW signal emitted is the same as in GR.
We generically find that tensor interactions lead to copies of the
originally emitted GW signal, each one with its own possibly
modified dispersion relation. These copies can travel coherently
and interfere with each other leading to a scrambled GW signal, or
propagate decoherently and lead to echoes arriving at different
times at the observer that could be misidentified as independent GW
events. Depending on the type of tensor interaction, the detected
GW signal may exhibit amplitude and phase distortions with respect
to a GW waveform in GR, as well as birefringence effects. We
discuss observational probes of these tensor interactions with both
individual GW events, as well as population studies for both ground-
and space-based detectors.
Two-component millicharged dark matter and the EDGES 21 cm signal *
Authors: Li Qiaodan , Liu Zuowei 
Published: November 2021

Abstract
We propose a two-component dark matter explanation to the EDGES 21 cm anomalous signal. The heavier dark matter component is long-lived, and its decay is primarily responsible for the relic abundance of the lighter dark matter, which is millicharged. To evade the constraints from CMB, underground dark matter direct detection, and XQC experiments, the lifetime of the heavier dark matter has to be larger than

, where

is the age of the universe. Our model provides a viable realization of the millicharged dark matter model to explain the EDGES 21 cm signal, since the minimal model in which the relic density is generated via thermal freeze-out has been ruled out by various constraints.
Recent results from deuterium experiments on the large helical device and their contribution to fusion reactor development
Authors: Osakabe Masaki , Takahashi Hiromi , Yamada Hiroshi , Tanaka Kenji , Kobayashi Tatsuya , Ida Katsumi , Ohdachi Satoshi , Varela Jacobo , Ogawa Kunihiro , Kobayashi Masahiro , Tsumori Katsuyoshi , Ikeda Katsunori , Masuzaki Suguru , Tanaka Masahiro , Nakata Motoki , Murakami Sadayoshi , Inagaki Shigeru , Mukai Kiyofumi , Sakamoto Mizuki , Nagasaki Kazunobu , Suzuki Yasuhiro , Isobe Mitsutaka , Morisaki Tomohiro , LHD Experiment Group the 
Published: November 2021

Abstract
In recent deuterium experiments on the large helical device (LHD), we succeeded in expanding the temperature domain to higher regions for both electron and ion temperatures. Suppression of the energetic particle driven resistive interchange mode (EIC) by a moderate electron temperature increase is a key technique to extend the high temperature domain of LHD plasmas. We found a clear isotope effect in the formation of the internal transport barrier in high temperature plasmas. A new technique to measure the hydrogen isotope fraction was developed in the LHD in order to investigate the behavior of the isotope mixing state. The technique revealed that the non-mixing and the mixing states of hydrogen isotopes can be realized in plasmas. In deuterium plasmas, we also succeeded in simultaneously realizing the formation of the edge transport barrier (ETB) and the divertor detachment. It is found that resonant magnetic perturbation plays an important role in the simultaneous formation of the ETB and the detachment. Contributions to fusion reactor development from the engineering point of view, i.e. negative-ion based neutral beam injector research and the mass balance study of tritium, are also discussed.
Multi-nucleon transfer reactions at ion catcher facilities - a new way to produce and study heavy neutron-rich nuclei
Authors: Dickel T. , Kankainen A. , Spătaru A. , Amanbayev D. , Beliuskina O. , Beck S. , Constantin P. , Benyamin D. , Geissel H. , Gröf L. , Hornung C. , Karpov A. V. , Mardor I. , Mu¨nzenberg G. , Nichita D. , Plaß W. R. , Pohjalainen I. , Purushothaman S. , Reponen M. , Rotaru A. , Saiko V.V. , Scheidenberger C. , Winfield J. S. , Zadvornaya A. 
Published: November 2021

Abstract
The production of very neutron-rich nuclides heavier than fission fragments is an ongoing experimental challenge. Multi-nucleon transfer reactions (MNT) have been suggested as a method to produce these nuclides. By thermalizing the reaction products in gas-filled stopping cells, we can deliver them as cooled high-quality beams to decay, laser and mass spectrometry experiments. High precision mass spectrometry will allow for the first time to universally and unambiguously identify the atomic and proton numbers of the ions produced in MNT reactions. In this way their ground and isomeric state properties can be studied in high-precision measurements. In experiments at IGISOL, Finland and at FRS Ion Catcher, Germany, we have done and will perform broadband measurements of the reaction products, with the aim to improve the understanding of the reaction mechanism and to determine the properties of the ground and isomeric states of the produced nuclides. First results and preparations for upcoming experiments are presented.
The Study of the 6Li(p,γ)7Be Reaction at LUNA
Authors: Piatti D. 
Published: November 2021

Abstract
The 6Li(p,γ)7Be reaction is mainly involved in two astrophysical scenarios: the primordial nucleosynthesis and 6Li consumption in pre-main and main sequence stars. A recent measurement of 6Li(p,γ)7Be reaction S-factor reported a resonance-like structure at Ecm = 195 keV, which has not been confirmed neither by other direct measurements nor by theoretical calculations.
A new experiment was performed at the Laboratory for Underground Nuclear Astrophysics (LUNA). The extremely low background environment allowed to measure the 6Li(p,γ)7Be cross section down to low energies with unprecedented sensitivity leading to clarify the existence of the claimed resonance. Details on the experimental setup and the preliminary results of the ongoing analysis are reported in this work.
40 year anniversary of the RADAN systems – compact pulsed power sources for various investigations
Authors: Shpak V G , Shunailov S A , Yalandin M I 
Published: November 2021

Abstract
This article includes a brief overview of the compact RADAN-series subgigawatt pulsed voltage sources and describes their capabilities in various electrophysical researches. We present the results obtained in the experiments at nano- and subnanosecond time scales on the formation of the voltage pulses with a special shape, electron beams emission in air gaps and by the cold cathodes in vacuum, as well as generation of electromagnetic radiation. Particular attention is paid to the promising application of the RADAN systems.
Subnanosecond breakdown of air-insulated coaxial line initiated by runaway electrons in the presence of a strong axial magnetic field
Authors: Mesyats G A , Osipenko E A , Sharypov K A , Shpak V G , Shunailov S A , Yalandin M I , Zubarev N M 
Published: November 2021

Abstract
Flow of runaway electrons (RAEs) propagating in a radial, air-filled gap of coaxial line (CL) changes the dynamics of breakdown in the field of traveling voltage pulse. However, despite the effect of RAEs, breakdown does not occur if subnanosecond pulse is less in duration and amplitude than some values. In this work, we study the influence of an external axial magnetic field (B
z) on the breakdown development. We demonstrate the transformation of the voltage pulse reflection from the ionized (breakdown) zone with changing B
z. Due to gyration of fast electrons in an applied magnetic field, the gas region ionized by RAEs does not reach the anode. The ionized bridge between the cathode and anode is gradually replaced by a near-cathode plasma layer representing a discrete, reflecting/absorbing inhomogeneity in the CL.