bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plasmon modes in N-layer silicene structures
Authors: Men Nguyen Van 
Published: November 2021

Abstract
We investigate the plasmon properties in N-layer silicene systems consisting of N, up to 6, parallel single-layer silicene (SLS) under the application of an out-of-plane electric field, taking into account the spin–orbit coupling within the random-phase approximation. Numerical calculations demonstrate that N undamped plasmon modes, including one in-phase optical (Op) and (N − 1) out-of-phase acoustic (Ac) modes, continue mainly outside the single-particle excitation area of the system. As the number of layers increases, the frequencies of plasmonic collective excitations increase and can become much larger than that in SLS, more significant for high-frequency modes. The Op (Ac) plasmon mode(s) noticeably (slightly) decreases with the increase in the bandgap and weakly depends on the number of layers. We observe that the phase transition of the system weakly affects the plasmon properties, and as the bandgap caused by the spin–orbit coupling equal that caused by the external electric field, the plasmonic collective excitations and their broadening function in multilayer silicene behave similarly to those in multilayer gapless graphene structures. Our investigations show that plasmon curves in the system move toward that in SLS as the separation increases, and the impacts of this factor can be raised by a large number of layers in the system. Finally, we find that the imbalanced carrier density between silicene layers significantly decreases plasmon frequencies, depending on the number of layers.
Contact time of impacting droplets on a superhydrophobic surface with tunable curvature and groove orientation
Authors: Guo Chunfang , Liu Lei , Liu Changwan 
Published: November 2021

Abstract
Regulating the impact dynamics of water droplets on a solid surface is of great significance for some practical applications. In this study, the droplet impingement on a flexible superhydrophobic surface arrayed with micro-scale grooves was investigated experimentally. The surface was curved into cylindrical shapes with certain curvatures from two orthogonal directions, where axial and circumferential grooves were formed, respectively. The effects of curvature diameter and Weber number, as well as the orientation of grooves on droplet spreading and retracting dynamics were analyzed and explained. Results show that the circumferential grooves promote the spreading of a droplet in the azimuthal direction, where the droplet rebounds from the surface with a stretched shape. This mechanism further reduces the contact time of impacting droplets on the superhydrophobic surface compared to the other curving mode.
A review of radiation doses and associated parameters in Western Australian mining operations (2018–20)
Authors: Ralph Martin I , Cattani Marcus 
Published: November 2021

Abstract
In the 2019–20 reporting period, 19 mining operations in Western Australia were identified as having workers who were likely to be exposed to ionising radiation stemming from naturally occurring radioactive materials, 17 of which, known hereinafter as reporting entities (REs), were required to submit an annual report of the dose estimates of their workforce to the mining regulatory authority. In 2018 the International Commission for Radiological Protection published the revision of the dose coefficients (DCs) for occupational intakes of radionuclides of the uranium-238 and thorium-232 decay series, in ICRP-137 and ICRP-141. The 2019–20 annual reports are the first to apply the revised DCs to estimate worker doses. The mean effective dose (ED) reported by the 17 REs increased by 32.4% to 0.94 mSv in 2019–20 from 0.71 mSv reported in 2018–19, indicating that the mean ED is approaching the 1 mSv annual dose estimate at which regulatory intervention should be considered. The mean committed effective dose (CED) from inhalation of dusts containing long-lived alpha-emitting (LLα) nuclides has increased by 35% from 0.40 mSv in 2018–19 to 0.54 mSv in 2019–20. The maximum CED from LLα increased by 16.3% from 3.20 mSv in 2018–19 to 3.72 mSv in 2019–20. The authors consider that, in the absence of other explanations provided by the REs, the increase is largely attributable to the revised DC’s published in ICRP-137 and ICRP-141, but highlight that there are significant variations between REs that make a generalised conclusion problematic. The maximum reported ED in 2019–20 was 6.0 mSv, an increase of 36.4% from 2018 to 2019 (4.4 mSv). The 2019–20 reporting period is the first time in a decade in which mine worker EDs have been elevated to the point that EDs have exceeded 5 mSv, a level at which personal monitoring and additional institutional controls are required.
From coarse to fine: an augmented reality-based dynamic inspection method for visualized railway routing of freight cars
Authors: Yi Bing , Sun Renkai , Long Liu , Song Yongfeng , Zhang Yinggui 
Published: November 2021

Abstract
The dynamic inspection of railway routes for freight cars transporting cargo that is out of gauge is a challenge. One possible way is using the inspection frame installed in the inspection train to simulate the whole procedure for cargo transportation, which requires a lot of manpower and material resources as well as time. To overcome the above problem, this paper proposes an augmented reality-based dynamic inspection method for visualized railway routing of freight cars with out-of-gauge cargo. First, an envelope model of the dynamic moving train with out-of-gauge cargo is generated using the orbital spectrum of the railway, and the envelope model is matched with a piece of homemade calibration equipment located at the position of the railway that needs to be inspected. Then, the structure from motion algorithm is used to reconstruct the environment where the virtual envelope model occludes the buildings or equipment along the railway. Finally, the distance function is adopted to calculate the distance between the obstacle and the envelope of the out-of-gauge freight car, determining whether the freight car can pass a certain line. The experimental results show that the proposed method performs well for the route selection of out-of-gauge cargo transportation with low cost, high precision, and high efficiency. Moreover, the digital data of the environments along the railway and the envelope of the freight car can be reused, which will increase the digitalization and intelligence for route selection of out-of-gauge cargo transportation.
Regulating oxygen vacancies in Co3O4 by combining solution reduction and Ni2+ impregnation for oxygen evolution reaction
Authors: Tang Jinyu , Yao Lu , Ren Xiaoru , Shao Zhiyu , Cai Minmin , Gao Lu , Wu Xiaofeng 
Published: November 2021

Abstract
Oxygen vacancies are considered to be an important factor to influence the electronic structure and charge transport of electrocatalysts in the field of energy chemistry. Various strategies focused on oxygen vacancy engineering are proved to be efficient for further improving the electrocatalytic performance of Co3O4. Herein, an optimal Co3O4 with rich oxygen vacancies have been synthesized via a two-step process combining solution reduction and Ni2+ impregnation. The as-prepared electrocatalyst exhibits an enhanced oxygen evolution performance with the overpotential of 330 mV at the current density of 10 mA cm−2 in alkaline condition, which is 84 mV lower than that of pristine one. With the increasing of oxygen vacancies, the charge transfer efficiency and surface active area are relatively enhanced reflected by the Tafel slope and double-layer capacitance measurement. These results indicate that combination of solution reduction and heteroatom doping can be a valid way for efficient metal oxides-based electrocatalyst development by constructing higher concentration of oxygen vacancy.
Degradation performance and mechanism toward methyl orange via nanoporous copper powders fabricated by dealloying of ZrCuNiAl metallic glassy precursors
Authors: Gu Lingyu , Wang Shushen , Hui Xidong , Li Fudong , Lin Hengfu , Wu Kaiming 
Published: November 2021

Abstract
The catalyst of nanoporous Cu (NP-Cu) powders, with the chemical composition of Cu79.63Ni6.85O13.53 (at%), was successfully fabricated by dealloying of Zr–Cu–Ni–Al metallic glassy precursors. The as-prepared NP-Cu powders, co-existing with Cu2O phase on Cu ligament surface, had a three-dimensional network porous structure. The NP-Cu powders/H2O2 system showed superior catalytic degradation efficiency toward azo dyes in both acidic (pH 2) and neutral (pH 7) environments. Moreover, the cyclic tests indicated that this powder catalyst also exhibited good durability. A novel degradation mechanism of NP-Cu powders/H2O2 was proposed: the high degradation performance in acidic environment was mainly derived from heterogeneous reaction involved with a specific pathway related to Cu3+ to produce HO·, while in neutral environment it was primarily resulted from homogeneous reaction with the generation of HO· from the classical Cu-based Fenton-like process. This work indicates that the NP-Cu powders have great potential applications as catalysts for wastewater treatments.
Bottom-up nanoscale patterning and selective deposition on silicon nanowires
Authors: Mohabir Amar T , Aziz Daniel , Brummer Amy C , Taylor Kathleen E , Vogel Eric M , Filler Michael A 
Published: November 2021

Abstract
We demonstrate a bottom-up process for programming the deposition of coaxial thin films aligned to the underlying dopant profile of semiconductor nanowires. Our process synergistically combines three distinct methods—vapor–liquid–solid nanowire growth, selective coaxial lithography via etching of surfaces (SCALES), and area-selective atomic layer deposition (AS-ALD)—into a cohesive whole. Here, we study ZrO2 on Si nanowires as a model system. Si nanowires are first grown with an axially modulated n-Si/i-Si dopant profile. SCALES then yields coaxial poly(methyl methacrylate) (PMMA) masks on the n-Si regions. Subsequent AS-ALD of ZrO2 occurs on the exposed i-Si regions and not on those masked by PMMA. We show the spatial relationship between nanowire dopant profile, PMMA masks, and ZrO2 films, confirming the programmability of the process. The nanoscale resolution of our process coupled with the plethora of available AS-ALD chemistries promises a range of future opportunities to generate structurally complex nanoscale materials and electronic devices using entirely bottom-up methods.
Reduction of EUV resist damage by neutral beam etching
Authors: Kim Gyo Wun , Chang Won Jun , Kang Ji Eun , Kim Hee Ju , Yeom Geun Young 
Published: November 2021

Abstract
Even though EUV lithography has the advantage of implenting a finer pattern compared to ArF immersion lithography due to the use of 13.5 nm instead of 193 nm as the wavelength of the light source, due to the low energy of EUV light source, EUV resist has a thinner thickness than conventional ArF resist. EUV resist having such a thin thickness is more vulnerable to radiation damage received during the etching because of its low etch resistance and also tends to have a problem of low etch selectivity. In this study, the radiation damage to EUV resist during etching of hardmask materials such as Si3N4, SiO2, etc using CF4 gas was compared between neutral beam etching (NBE) and ion beam etching (IBE). When NBE was used, after the etching of 20 nm thick EUV resist, the line edge roughness increase and the critical dimension change of EUV resist were reduced by ∼1/3 and ∼1/2, respectively, compared to those by IBE. Also, at that EUV etch depth, the root mean square surface roughness value of EUV resist etched by NBE was ∼2/3 compared to that by IBE on the average. It was also confirmed that the etching selectivity between SiO2, Si3N4, etc and EUV resist was higher for NBE compared to IBE. The less damage to the EUV resist and the higher etch selectivity of materials such as Si3N4 and SiO2 over EUV resist for NBE compared to IBE are believed to be related to the no potential energy released by the neutralization of the ions during the etching by NBE.
Fatigue and its effect on the piezopotential properties of gallium nitride nanowires
Authors: Zhang Jin , Du Yao 
Published: November 2021

Abstract
The gallium nitride (GaN) nanowires (NWs) in piezotronic applications are usually under cyclic loading, which thus may inevitably suffer the mechanical fatigue. In this paper, the fatigue behaviours of defective GaN NWs are investigated by using molecular dynamics (MD) simulations. Our results show no significant changes in the molecular structures of GaN NWs until their final failure during the fatigue process. The final fracture occurring in the GaN NWs under fatigue loading is triggered by the crack that unusually initiates from the NW surface. The GaN NW with a smaller defect concentration or under the fatigue load with a smaller amplitude is found to possess a longer fatigue life. In addition, the ultimate fatigue strain of GaN NWs can be significantly increased by reducing the defect concentration of NWs. The material parameters including elastic constants, piezoelectric coefficients, and dielectric constants of GaN NWs in the fatigue test are evaluated through MD simulations, all of which are found to keep almost unchanged during the fatigue process. These material parameters together with the band gaps of GaN NWs extracted from first-principles calculations are employed in finite element calculations to investigate the piezopotential properties of GaN NWs under fatigue loading. No significant changes are found in the piezopotential properties of GaN NWs during the fatigue process, which indicates the long-term dynamic reliability of GaN NWs in piezotronic applications.
Citrate-capped gold nanoparticles with a diameter of 14 nm alter the expression of genes associated with stress response, cytoprotection and lipid metabolism in CaCo-2 cells
Authors: Wusu Adedoja Dorcas , Sibuyi Nicole Remaliah Samantha , Moabelo Koena Leah , Goboza Mediline , Madiehe Abram , Meyer Mervin 
Published: November 2021

Abstract
Advancements in nanotechnology have provided insight into the unique opportunities for the application of nanomaterials such as gold nanoparticles (AuNPs) in medicine due to their remarkable properties, which includes low toxicity, large surface area, and the ease of synthesis and conjugation to other molecules. Therefore, AuNPs are often preferred for bio-applications. Citrate-capped AuNPs (cAuNPs) have been reported to be non-cytotoxic and are used in numerous studies as drug delivery vehicles to treat various diseases. However, the limitations of bioassays often used to assess the toxicity of AuNPs have been well documented. Herein, we investigate the cytotoxicity of 14 nm cAuNPs in the human colorectal adenocarcinoma (Caco-2) cell line. Treatment conditions (i.e. dose and exposure time) that were established to be non-toxic to Caco-2 cells were used to investigate the effect of cAuNPs on the expression of a Qiagen panel of 86 genes involved in cytotoxicity. Out of 86 studied, 23 genes were differentially expressed. Genes involved in oxidative stress and antioxidant response, endoplasmic reticulum (ER) stress and unfolded protein response, heat shock response, and lipid metabolism were more affected than others. While low concentrations of 14 nm cAuNPs was not cytotoxic and did not cause cell death, cells treated with these nanoparticles experienced ER and oxidative stress, resulting in the activation of cytoprotective cellular processes. Additionally, several genes involved in lipid metabolism were also affected. Therefore, 14 nm cAuNPs can safely be used as drug delivery vehicles at low doses.
High-performance plasmonic lab-on-fiber sensing system constructed by universal polymer assisted transfer technique
Authors: Wang Guangrong , Wang Lei , Cheng Zhan , Chen Dan , Zhang Xuemin , Wang Tieqiang , Wang Qi , Fu Yu 
Published: November 2021

Abstract
Plasmonic lab-on-fiber (LOF) system has become an emerging sensing platform for the realization of miniaturized and portable plasmonic sensors. Herein, a facile and efficient polymer assisted transfer technique was reported for the preparation of plasmonic LOF systems. The proposed plasmonic LOF system was constructed through transferring plasmonic arrays to the end surface of optical fibers using polylactic acid as the sacrificial layer. The morphology of the transferred plasmonic arrays maintains excellent consistency with the original arrays. Importantly, the as-prepared plasmonic LOF system also possesses outstanding sensing performance in refractive index sensing and quantitative label-free biosensing applications. Additionally, the proposed polymer assisted transfer technique shows broad universality for various plasmonic arrays. Together with the above features, it is believed that the polymer assisted transfer technique will show great potential for the application of future plasmonic LOF systems.
Transfer learning for fluence map prediction in adrenal stereotactic body radiation therapy
Authors: Wang Wentao , Sheng Yang , Palta Manisha , Czito Brian , Willett Christopher , Yin Fang-Fang , Wu Qiuwen , Ge Yaorong , Wu Q Jackie 
Published: November 2021

Abstract

Objective: To design a deep transfer learning framework for modeling fluence map predictions for stereotactic body radiation therapy (SBRT) of adrenal cancer and similar sites that usually have a small number of cases. Approach: We developed a transfer learning framework for adrenal SBRT planning that leverages knowledge in a pancreas SBRT planning model. Treatment plans from the two sites had different dose prescriptions and beam settings but both prioritized gastrointestinal sparing. A base framework was first trained with 100 pancreas cases. This framework consists of two convolutional neural networks (CNN), which predict individual beam doses (BD-CNN) and fluence maps (FM-CNN) sequentially for 9-beam intensity-modulated radiation therapy (IMRT) plans. Forty-five adrenal plans were split into training/validation/test sets with the ratio of 20/10/15. The base BD-CNN was re-trained with transfer learning using 5/10/15/20 adrenal training cases to produce multiple candidate adrenal BD-CNN models. The base FM-CNN was directly used for adrenal cases. The deep learning (DL) plans were evaluated by several clinically relevant dosimetric endpoints, producing a percentage score relative to the clinical plans. Main results: Transfer learning significantly reduced the number of training cases and training time needed to train such a DL framework. The adrenal transfer learning model trained with 5/10/15/20 cases achieved validation plan scores of 85.4/91.2/90.7/89.4, suggesting that model performance saturated with 10 training cases. Meanwhile, a model using all 20 adrenal training cases without transfer learning only scored 80.5. For the final test set, the 5/10/15/20-case models achieved scores of 73.5/75.3/78.9/83.3. Significance: It is feasible to use deep transfer learning to train an IMRT fluence prediction framework. This technique could adapt to different dose prescriptions and beam configurations. This framework potentially enables DL modeling for clinical sites that have a limited dataset, either due to few cases or due to rapid technology evolution.
A novel method to assess the spatiotemporal image quality in fluoroscopy
Authors: Monnin P , Viry A , Damet J , Nowak M , Vitzthum V , Racine D 
Published: November 2021

Abstract

Objectives. The planar formulation of the noise equivalent quanta (NEQ) and detective quantum efficiency (DQE) used to assess the image quality of projection images does not deal with the influence of temporal resolution on signal blurring and image noise. These metrics require correction factors based on temporal resolution when used for dynamic imaging systems such as fluoroscopy. Additionally, the standard NEQ and detector DQE are determined on pre-processed images in scatter-free conditions for effective energies produced by additional aluminium or copper filters that are not representative of clinical fluoroscopic procedures. In this work, we developed a method to measure ‘frame NEQ’ and ‘frame system DQE’ which include the temporal frequency bandwidth and consider the anti-scatter grid, the detector and the image processing procedures for beam qualities with scatter fractions representative of clinical use. Approach. We used a solid water phantom to simulate a patient and a thin copper disc to measure the spatial resolution. The copper disc, set in uniform rectilinear motion in the image plane, assessed the temporal resolution. These new metrics were tested on two fluoroscopy systems, a C-arm and a floor-mounted cardiology, for multiple parameters: phantom thicknesses from 5 to 20 cm, frame rates from 3 to 30 fps, spatial and temporal image processing of different weights. Main results. The frame NEQ correctly described the image quality for different scatter conditions, temporal resolutions and image processing techniques. The frame system DQE varied between 0.38 and 0.65 within the different beam and scatter conditions, and correctly mitigated the influence of spatial and temporal image processing. Significance. This study introduces and validates an unbiased formulation of in-plane NEQ and system DQE to assess the spatiotemporal image quality of fluoroscopy systems.
One dimensional reduced model for ITER relevant energetic particle transport
Authors: Carlevaro N , Meng G , Montani G , Zonca F , Hayward-Schneider T , Lauber Ph. , Lu Z , Wang X 
Published: November 2021

Abstract
We set up a mapping procedure able to translate the evolution of the radial profile of fast ions, interacting with toroidal Alfvén Eigenmodes, into the dynamics of an equivalent one-dimensional bump-on-tail system. We apply this mapping technique to reproduce the relevant ITER simulations, which clearly outline deviations from the diffusive quasi-linear (QL) model. Our analysis demonstrates the capability of the one-dimensional beam-plasma dynamics to predict the relevant features of the non-linear hybrid LIGKA/HAGIS simulations. In particular, we clearly identify how the deviation from the QL evolutive profiles is due to the presence of avalanche processes. A detailed analysis regarding the reduced dimensionality is also addressed, by means of phase-space slicing based on constants of motion. In the conclusions, we outline the main criticalities and outcomes of the procedure, which must be satisfactorily addressed to make quantitative predictions on the observed outgoing fluxes in a Tokamak device.
Novel features of electromagnetic waves in an isotropic degenerate electron-ion plasma
Authors: Maryam P , Rozina Ch , Ali S , Shah H A , Poedts S 
Published: November 2021

Abstract
Within the framework of kinetic theory, the nonlinear interaction of electromagnetic waves (EMWs) with a degenerate electron-ion plasma is studied to account for the electron quantum mechanical effects. For this purpose, a specific quantum regime is considered, for which the degenerate electron Fermi velocity is assumed to be of the order of the group velocity of EMWs. This eventually leads to the existence of a nonlinear Landau damping rate for the EMWs in the presence of electron ponderomotive force. The electron–ion density oscillations may have arisen from the nonlinear interaction of EMWs, leading to a new type of nonlinear Schrödinger equation in terms of a complex amplitude for electromagnetic pump waves. The profiles of nonlinear damping rates reveal that EMWs become less damped for increasing the quantum tunneling effects. The electrostatic response of the linear electrostatic waves is also investigated and derived from a linear dispersion for the ion-acoustic damping rate. The latter is a direct function of the electron Fermi speed and does not rely on the Bohm tunneling effect. The obtained results are numerically analyzed for two microwaves of different harmonics in the context of nonrelativistic astrophysical dense plasma environments, e.g. white dwarfs, where the electron quantum corrections cannot be ignored.