bluuebunny/crossref_metadata_2025_split huggingface dataset:
The quantum scattering time in a linear potential
Authors: Xiao Zhi , Zheng Shuang , Liu Ji-Cai 
Published: April 2021

Abstract
In this paper, we calculate the quantum time delays for a neutral particle scattering off the Earth gravitational linear potential. The quantum time delays are obtained by subtracting the classical returning time (CRT) from the Wigner time, the dwell time and the Larmor time respectively. Different from the conventional definition, our Larmor time is defined by aligning the magnetic field along particle’s direction of motion, and this definition does give reasonable results for motions through a free region and a square barrier. It is worth noting that in the zero magnetic field limit, the Larmor time coincides well with the CRT, which is due to the special shape of linear barrier, and may have some relevance to the weak equivalence principle. It is also found that the classical forbidden region plays an essential role for the dwell time

τ

DW

to match with the CRT, and the difference between the dwell and the phase times, i.e. the self-interference time delay, is barrier shape sensitive and clearly shows the peculiarity of the linear barrier. All the time delays are on the order of sub-millisecond and exhibit oscillating behaviors, signaling the self-interference of the scattering particle, and the oscillations become evident only when the de Broglie wavelength λ

k
= 2π/k is comparable to the characteristic length

L

c

=

[

2

m

2

g
/

ℏ

2

]

−
1
/
3

. If the time delay measurement is experimentally realizable, it can probe the quantum nature for particle scattering off the gravitational potential in the temporal domain.
Measurement of the free electron line density in a spherical theta-pinch plasma target by single wavelength interferometry
Authors: Christ P , Cistakov K , Iberler M , Laghchioua L , Mann D , Rosmej O , Savin S , Jacoby J 
Published: April 2021

Abstract
A single wavelength heterodyne interferometer has been set up to investigate the free electron density integrated axially along the line of sight (line density) in a theta-pinch plasma to determine its applicability as a plasma target for ion beam stripping. The maximal line density reached in this experiment was

3

.

57
±
0

.

28

×

10

18

cm−2 at 80 Pa and 20 kV. The findings demonstrate the pulsed character of the line density and its increase by raising the load voltage and the working gas pressure. Additionally, the results were compared with spectroscopic free electron density estimations, which were carried out by H

β

-line broadening and peak separation. The time behavior of the line density indicates that its peak value is delayed by about 10 µs compared to the spectroscopic results. This effect is due to the formation of an extended, magnetically compressed plasma column in the vicinity of the current maximum, although the highest volumetric free electron density is reached near the current zero crossing. Since the line density is an essential parameter in describing the stripping capabilities of the plasma target, the interferometric diagnostic is superior to a spectroscopic diagnostic, because it directly provides integrated values along the line of sight. Furthermore, the measurements of the line density in this experiment partially show nonphysical negative values, which is due to gaseous effects and residual shot vibrations.
Experimental observation of the linear gain of back-illuminated ultraviolet avalanche photodiodes using a GaN/AlN periodically stacked structure
Authors: Kang Jianbin , Li Qian , Wan Yongbiao 
Published: April 2021

Abstract
Semiconductor-based avalanche photodiodes (APDs) have the advantages of lower power and simpler fabrication of arrays compared with photomultiplier tubes. It is critical for weak-light imaging that the APD is operated under back illumination and with high linear gain. However, linear gain is fairly low for conventional PIN APDs. This paper presents a back-illuminated APD, whose multiplication layer is designed to be a GaN/AlN periodically stacked structure. The GaN/AlN heterostructure is introduced to enhance the ratio of ionization coefficient between electrons and holes, which proves to be helpful for increasing the linear gain. Under back illumination, the prototype device demonstrates a record-high external quantum efficiency (reflecting linear gain) of ∼5 × 102 at the reverse bias of 66 V. The device response spectra were also studied to further confirm that only the photo-excited electrons can trigger the collision ionization in the multiplication layer.
Effects of 10 MeV Al4+ ions irradiation on fluorine-doped tin oxide substrates for photovoltaic device applications
Authors: Pandey Anand , Patel M S , Chaudhary Dhirendra K , Patel Shiv P , Pali L Sowjanya , Garg Ashish , Kumar Lokendra 
Published: April 2021

Abstract
The effects of 10 MeV Al4+ ions irradiation on structural, surface morphological, optical and electrical properties of fluorine-doped tin oxide (FTO) substrates are presented for solar cell applications. The ions irradiation changes the surface morphology, average roughness, interface width, roughness exponent, and several other fractal parameters of the FTO surfaces. The UV–visible transmittance measurement shows an enhancement of transmittance in the ions irradiated substrates up to 95%. The electrical properties such as mobility, work-function, sheet resistance, and resistivity are also modified due to ions irradiation. In order to have functional applications of these ions irradiated substrates, we fabricated organic solar cells on these ions irradiated and pristine FTO substrates. The device performances are significantly improved for the case of ions irradiated FTO substrate in comparison to the pristine one. Thus, better device performance due to effective changes in physical properties suggests that the ions irradiated FTO substrates can be used as better electrodes for organic and hybrid photovoltaic device applications.
Semiconductor heterojunction photocatalysts with near-infrared light antennas: a review
Authors: Lu Yue , Wang Yuyan , Zhang Junying 
Published: April 2021

Abstract
Photocatalysts are expected to contribute to the sustainable development of human society due to their ability of converting solar energy to chemical fuel and removing environmental contamination. In principle, photocatalytic efficiency is intimately related to the availability of sunlight, and thus it is vital to extend the light absorption range to the low-energy near-infrared (NIR) region. A great deal of effort has been devoted to exploring NIR-driven photocatalysts and consequently various light antennas have been reported, which can be coupled with wide bandgap semiconductors to form heterojunctions. In this review, recent progress in NIR-driven heterojunction photocatalysts is summarized, introducing in detail the variety and functionality of four types of light antennas including dyes, up-conversion carbon-based quantum dots, plasmonic materials and narrow bandgap semiconductors. This review emphasizes the effects of the heterojunction structure on the photocatalytic properties and summarizes the representative research results of NIR light antennas, aiming to promote the exploration of novel NIR light harvesting materials.
Vector magneto-optical magnetometer based on resonant all-dielectric gratings with highly anisotropic iron garnet films
Authors: Ignatyeva Daria O , Knyazev Grigory A , Kalish Andrey N , Chernov Alexander I , Belotelov Vladimir I 
Published: April 2021

Abstract
Sensitive vector magnetometry with high spatial resolution is important for various practical applications, such as magnetocardiography, magnetoencephalography, explosive materials detection and many others. We propose a magnetometer based on magnetic iron garnet film possessing a very high magnetic anisotropy, placed in a rotating external magnetic field. Each of the measured magnetic field spatial components produces different temporal harmonics in the out-of-plane magnetization dependence. Our analysis based on numerical simulation shows that the dielectric resonant grating placed on the top of an ultrathin film enhanced the magneto-optical (MO) response by ten times. It allows one to reduce the thickness of the film, which makes it possible to achieve several times higher spatial resolution in the perpendicular to the film direction, up to 30 nm. The reported MO magnetometer allows one to measure simultaneously all three spatial components of the magnetic field with high spatial resolution and sensitivity up to 100 pT Hz-1/2.
Effect of the uncertainty in the hadronic interaction models on the estimation of the sensitivity of the Cherenkov telescope array
Authors: Ohishi Michiko , Arbeletche Luan , de Souza Vitor , Maier Gernot , Bernlöhr Konrad , Olaizola Abelardo Moralejo , Bregeon Johan , Arrabito Luisa , Yoshikoshi Takanori 
Published: April 2021

Abstract
Imaging atmospheric Cherenkov telescopes (IACTs) are ground-based indirect detectors for cosmic gamma rays with energies above tens of GeV. The major backgrounds for gamma-ray observations in IACTs are cosmic-ray charged particles. The capability to reject these backgrounds is the most important factor determining the gamma-ray sensitivity of IACT systems. Monte Carlo simulations are used to estimate the residual background rates and sensitivity of the systems during the design and construction phase. Uncertainties in the modeling of high-energy hadronic interactions of cosmic rays with nuclei in the air propagate into the estimates of residual background rates and subsequently into the estimated instrument sensitivity. We investigate the influence of the difference in the current hadronic interaction models on the estimated gamma-ray sensitivity of the Cherenkov Telescope Array using four interaction models (QGSJET-II-03, QGSJET-II-04, EPOS-LHC, and SIBYLL2.3c) implemented in the air shower simulation tool CORSIKA. Variations in background rates of up to a factor 2 with respect to QGSJET-II-03 are observed between the models, mainly due to differences in the π
0 production spectrum. These lead to ∼30% differences in the estimated gamma-ray sensitivity in the 1–30 TeV region, assuming a 50 h observation of a gamma-ray point-like source. The presented results also show that IACTs have a significant capability in the verification of hadronic interaction models.
Spin correlations and spin-density wave phase in a finite-temperature quasi-one-dimensional electron gas
Authors: Kaur Kulveer , Sharma Akariti , Garg Vinayak , Moudgil R K 
Published: April 2021

Abstract
In this paper, we theoretically investigate the effect of temperature on spin correlations in an unpolarized quasi-one-dimensional electron gas (Q1DEG). The correlations are treated dynamically within quantum version of the self-consistent mean-field approach of Singwi et al Numerical results for the ↑↑ and ↑↓ components of static structure factor and pair-correlation function, and the wave vector dependent static spin and charge susceptibilities are presented over a wide range of temperature T and electron coupling r

s
. We find that the recently reported (2020 J. Phys.: Condens. Matter.
32 335403) non-monotonic T-dependence of the contact pair-correlation function g(r = 0; T) is driven primarily by an interplay between ↑↓ correlations and thermal effects. At a given temperature, the dynamics of both ↑↑ and ↑↓ correlations is found to become significant with increasing coupling r

s
, manifesting unambiguously as pronounced peak at 3.5k
F (periodic oscillations) in the corresponding components of the structure factor (pair-correlation function). Analysis of static spin and charge susceptibilities reveals that an imbalance between ↑↑ and ↑↓ correlations may induce a transition to a spin-density wave (SDW) phase of wave vector ∼3.5k
F above a critical coupling for a sufficiently high T, while to a long-wavelength SDW phase at a low T. Higher the temperature, higher is the predicted critical coupling for the SDW phase. Interestingly, transition to the SDW phase is found to precede the recently predicted Wigner crystal instability in the finite-T Q1DEG. Further, if one starts with partially spin-polarized electrons, the SDW instability is found to shift to somewhat higher τ and r

s
. In addition, we have presented results for the free exchange-correlation energy, free correlation energy, and excess kinetic energy for the unpolarized and fully spin-polarized phases of the finite-T Q1DEG. Wherever interesting, we have compared our results with the predictions of the static version of the mean-field approach.
Personal dosimeter utilisation among South African interventionalists
Authors: Rose André , Uebel Kerry , Rae William Ian Duncombe 
Published: April 2021

Abstract
Ionising radiation (IR) is increasingly being used in diagnostic and therapeutic procedures and offers increased benefits to patients but poses an increased occupational health risk to operators. The consistent use and monitoring of radiation health care workers’ dosimeters is an important part of the process for ensuring adequate monitoring and control of IR in the workplace. There is however often inconsistent dosimeter utilisation among these workers. The aim of this study was to report on the dosimeter utilisation and dosimetry practices in South African interventionalists. We conducted a survey and did in-depth and group interviews to evaluate dosimetry practices and the factors influencing these practices. We used STATA 15 to do a descriptive analysis of the quantitative data. A thematic analysis of the qualitative data was done using a deductive and inductive approach. There were 108 respondents (35 radiologists, 41 adult cardiologists, 32 paediatric cardiologists). The majority overall (65.8%), and in each category were males. The median age was 44 (interquartile range (IQR) 31–66)) and the median years worked with fluoroscopy was 10 years (IQR 1–32). Overall interventionalists (55%) ranked their perceived occupation risk as 2/10. Thirteen per cent of all interventionalists reported never using a personal dosimeter (PD), 58% reported wearing it >70% of the time. Inconsistent and inappropriate use of PDs emerged strongly from the qualitative data. There was poor dosimeter utilisation in this study. Participants were not aware of the role of medical physics departments. Evaluation of dosimetry practices as a means of monitoring and improving radiation safety in the catheterisation laboratory must be improved to create an improved culture of radiation safety and protection.
In situ tailoring the morphology of In(OH)3 nanostructures via surfactants during anodization and their transformation into In2O3 nanoparticles
Authors: Ali Tariq , Mohyuddin Saima , Ali Ghafar , Khan Maaz , Iqbal Sajid , Maqbool Muhammad , Cho Sung Oh 
Published: April 2021

Abstract
The present work reports the effect of various surfactants on the morphology of In(OH)3 nanostructures prepared via anodization. In-sheets were anodized in an environmentally benign electrolyte containing a small quantity of CTAB, CTAC, and PDDA surfactants at room temperature. The produced nanostructures were characterized using XRD, HRTEM, SAED, and EDAX. The morphology of indium hydroxide (In(OH)3) nanostructures was successfully tailored in situ with the help of surfactants in 1 M KCl aqueous electrolyte. XRD results confirmed the formation of In(OH)3 and indium oxyhydroxide (InOOH) nanostructures in the pristine form which were transformed into single-phase cubic In2O3 nanoparticles (NPs) after calcination. HRTEM analyses showed that the morphology and size of the In(OH)3 nanostructures can be tuned to form nanorods, nanosheets and nanostrips using different surfactants. The results revealed that CTAC and PDDA surfactants have a profound effect on the morphology of In(OH)3 nanostructure compared to CTAB due to the higher concentration of Cl− ion. The possible mechanism of surfactants effect on the morphology is proposed. Furthermore, annealing converted the In(OH)3 nanostructures into spherical In2O3 NPs with uniform and homogeneous size. We anticipate that the morphology of other metal-oxides nanostructure can be tuned using this simple, facile and rapid technique. In2O3 NPs prepared without and with CTAB surfactant were further explored for the non-enzymatic detection of hydrogen peroxide (H2O2). Electrochemical measurements showed enhanced electrocatalytic performance with fast electron transfer (∼2s) between the redox centers of H2O2 and electrode surface. The In2O3 NPs prepared using CTAB/Au electrode exhibited about 4-fold increase in sensitivity compared to the bare Au electrode. The biosensor also demonstrated good reproducibility, higher selectivity, and increased shelf life.
Size effect of hybrid carbon nanofillers on the synergetic enhancement of the properties of HDPE-based nanocomposites
Authors: Evgin Tuba , Turgut Alpaslan , Hamaoui Georges , Špitalský Zdeno , Horny Nicolas , Altay Lütfiye , Chirtoc Mihai , Omastová Mária 
Published: April 2021

Abstract
High-density polyethylene (HDPE)-based hybrid nanocomposites containing graphene nanoplatelets (GnPs) and multiwall carbon nanotubes (MWCNTs) were fabricated using melt mixing followed by compression molding. The influences of size and weight ratio of both carbon-based nanofillers on the electrical, thermal, and mechanical properties of hybrid nanocomposites were evaluated. This study proves that the size and weight ratio of carbon-based nanofillers play a critical role in determining these properties. The optimum size and weight ratio of GnPs and MWCNTs are determined at the maximum achieved enhancement for each property. The HDPE-based nanocomposites containing GnPs with larger surface area and MWCNTs with higher aspect ratio display the highest electrical conductivity at GnPs/MWCNTs weight ratio of 2/3. The combination of GnPs with larger surface area and MWCNTs with lower aspect ratio provides the maximum Young’s modulus enhancement of hybrid nanocomposites at 1/4 weight ratio of GnPs and MWCNTs. The nanocomposite containing GnPs with the largest lateral size and MWCNTs with a higher aspect ratio at a 3/2 weight ratio exhibits the highest thermal conductivity. Also, at around the percolation threshold of GnPs, the incorporation of MWCNTs with larger aspect ratio into the HDPE-based nanocomposites containing GnPs with the largest lateral size shows a distinct synergic effect on the thermal conductivity and Young’s modulus, while an additive effect on the electrical conductivity and thermal stability.
Cell surface nucleolin as active bait for nanomedicine in cancer therapy: a promising option
Authors: Ferrara Benedetta , Belbekhouche Sabrina , Habert Damien , Houppe Claire , Vallée Benoit , Bourgoin-Voillard Sandrine , Cohen José L , Cascone Ilaria , Courty José 
Published: April 2021

AbstractConventional chemotherapy used against cancer is mostly limited due to their non-targeted nature, affecting normal tissue and causing undesirable toxic effects to the affected tissue. With the aim of improving these treatments both therapeutically and in terms of their safety, numerous studies are currently being carried out using nanoparticles (NPs) as a vector combining tumor targeting and carrying therapeutic tools. In this context, it appears that nucleolin, a molecule over-expressed on the surface of tumor cells, is an interesting therapeutic target. Several ligands, antagonists of nucleolin of various origins, such as AS1411, the F3 peptide and the multivalent pseudopeptide N6L have been developed and studied as therapeutic tools against cancer. Over the last ten years or so, numerous studies have been published demonstrating that these antagonists can be used as tumor targeting agents with NPs from various origins. Focusing on nucleolin ligands, the aim of this article is to review the literature recently published or under experimentation in our research team to evaluate the efficacy and future development of these tools as anti-tumor agents.
All-yarn triboelectric nanogenerator and supercapacitor based self-charging power cloth for wearable applications
Authors: Ren Xiaohu , Xiang Xinyu , Yin Hongfeng , Tang Yun , Yuan Hudie 
Published: April 2021

Abstract
Despite rapid developments, multifunctional wearable electronics are still not significant in practical applications as compared to portable and stretchable power devices. In this paper, we present the flexible and easy large-scale production of single-electrode mode triboelectric nanogenerator (TENG) and supercapacitor yarn-based self-charging power fabric, for simultaneously converting and storing biomechanical energy. Fabricated using traditional knitting technologies, the self-charging power fabric can adapt to complex mechanical deformations owing to its high flexibility and stretchability. Additionally, the output characteristics of the TENG fabric were systematically investigated with the purpose of energy generation. The TENG fabric can generate a maximum peak power density of ∼90 mW·m−2 using nylon as the contact material, with an operating frequency of 4 Hz. The as-prepared yarn-based supercapacitor exhibited high capacitance, good cycling stability, and flexibility, making it an appropriate wearable energy-storage device. Moreover, the proposed design uses energy harvested from biomechanical motions to sustainably power portable electronic devices. The results of this study indicate that the proposed design is a promising sustainable power source for wearable electronic devices.
A deformable wireframe in a uniform magnetic field
Authors: Rizcallah Joseph A 
Published: April 2021

Abstract
The net force and net torque exerted by a uniform magnetic field on a rigid current-carrying loop are discussed in all introductory physics textbooks. A notable omission, however, is the discussion of the equilibrium of a deformable current-carrying loop in a uniform magnetic field. In the article, we present such an analysis for the simplest case of a quadrilateral current-carrying wireframe placed in a uniform magnetic field. We discuss the area-maximizing effect of the field on the frame and use the conditions of translational and rotational equilibrium to establish the ‘cyclicity’ of the latter as well as the uniformity of the magnitude of the contact forces acting at its joints.
Overview of plasma rotation studies on the TCABR tokamak
Authors: Severo J H F , Canal G P , Ronchi G , Andrade N B , Fernandes T , Ikeda M Y , Collares M P , Galvão R M O , Nascimento I C , Tendler M 
Published: April 2021

Abstract
An overview of intrinsic plasma rotation studies in Ohmic L-mode discharges carried out in the Tokamak Chauffage Alfvén Brésilien (TCABR) tokamak is presented. Measurements of plasma poloidal and toroidal rotation, and a comparison against neoclassical theory, are presented. The results show that poloidal rotation is in good agreement with neoclassical theory while toroidal rotation is found to be anomalous. A new technique that allows for high temporal resolution measurements of plasma rotation is presented. This technique is used to test two models of intrinsic toroidal rotation: the so-called Helander model (Helander et al 2003 Physics of Plasmas
10 4396) and Rozhansky model (Rozhansky 2013 Perpendicular currents and electric fields in fully and partially ionized magnetized plasma Physics of Plasmas
24 101614). As TCABR is a relatively small device, the influence of the neutrals that form the basis of this model is expected to be enhanced. The results indicate that the mechanism proposed by Helander does not contribute significantly to the intrinsic toroidal rotation in TCABR plasmas. The measurements, however, indicate that the frictional force proposed by Rozhansky might be responsible for part of the intrinsic toroidal rotation observed in TCABR plasmas.