bluuebunny/crossref_metadata_2025_split huggingface dataset:
Non–monotonic behaviour in the mean transverse energy of electrons emitted from a reflection–mode p-GaAs(Cs,O) photocathode during its QE degradation through oxygen exposure
Authors: Jones L B , Scheibler H E , Kosolobov S N , Terekhov A S , Militsyn B L , Noakes T C Q 
Published: February 2021

Abstract
We present a study on the evolution of both transverse and longitudinal energy distributions due to oxygen–induced quantum efficiency degradation in the electrons emitted from a reflection–mode p-GaAs(Cs,O)-photocathode over an effective electron affinity range of χ
*∼ −0.1 eV to χ
*∼ +0.3 eV under illumination wavelengths λ = 808, 635 and 532 nm. For λ = 635 and 532 nm, we found that the mean transverse energy of electrons emitted as the photocathode effective electron affinity increased has a non–monotonic character. Our proposed fitting model links the measured response to changes in the relative number of thermalised and non–thermalised electrons in the total emitted photocurrent.
Enhanced deep-ultraviolet sensing by an all-inorganic p-PZT/n-Ga2O3 thin-film heterojunction
Authors: Liu Zeng , Zhang Shaohui , Zhi Yusong , Li Shan , Yan Zuyong , Chu Xulong , Bian Ang , Li Peigang , Tang Weihua 
Published: February 2021

Abstract
In this work, an enhanced-performance deep-ultraviolet (DUV) photodetector based on a Ga2O3/lead zirconate titanate (Pb(Zr0.52Ti0.48)O3, PZT) p-n heterojunction is fabricated and characterized for the first time. Compared to a Ga2O3-based device, the heterojunction device achieved a lower dark current of 2.7

×

10−11 A, a higher photo- to dark-current ratio of 2

×

103, a higher responsivity of 5.5 mA W−1, a larger specific detectivity of 2.6

×

1011 Jones and a higher external quantum efficiency of 2.7% at −2 V under 254 nm UV light illumination with an intensity of 500 μW cm−2. The p-PZT/n-Ga2O3 was confirmed to be a potential candidate for the construction of DUV photodetectors with enhanced sensing performance.
Accurate 3D reconstruction of complex defects based on combined method of MFL and MFDs
Authors: Li Hengtao , Liu Xiucheng , Wu Bin , He Cunfu 
Published: February 2021

Abstract
The two-step strategy for 3D reconstruction of complex defects was updated by combining the magnetic field disturbance (MFD) with magnetic ﬂux leakage (MFL) measurement methods. Firstly, the plane-scanned MFD imaging was employed to achieve high-accuracy reconstruction of the opening outlines of complex defects. Secondly, the finite element simulation model of the defect with the recognized opening outline was established as the forward model for depth profile inversion with the particle swarm optimization algorithm. The performances of the conventional MFL-based and updated strategies were carefully compared through finite element simulation. The results proved that the updated method combining MFD signals with MFL signals had the better performance in accurate 3D reconstruction of complex defects than the conventional MFL-based inversion strategy, displaying smaller errors in opening outline, peak depth and the profile. Experimental results confirmed that the updated strategy could accurately reconstruct the 3D shape of 8-shaped defect and rectangular defect with rounded corners.
Optimally adding additional inertial sensors to an initial configuration of sensors to maximize the sensing accuracy
Authors: Sahu Nitesh , Babu Prabhu , Kumar Arun , Bahl Rajendar 
Published: February 2021

Abstract
In this paper, we solve the problem of optimally adding additional inertial sensors to any known initial configuration of inertial sensors. The initial known configuration may be the optimal configuration or any random configuration of sensors. In this problem, we do not change the initial configuration of sensors, instead we determine the optimal orientations of the sensors which are to be added. We have posed this problem as an optimization problem and proposed a novel method to solve this optimization problem. The proposed method is based on the majorization-minimization procedure. The proposed method has been implemented and tested via numerical simulations in MATLAB. The simulation results show that the proposed method converges to the optimal solution and hence determines the optimal orientations for the sensors which are added to any known configuration of the sensors.
A high sensitivity microwave glucose sensor
Authors: Shahri Atena A , Omidvar Amir H , Rehder Gustavo P , Serrano Ariana L C 
Published: February 2021

Abstract
A simple, sensitive, low-cost microwave sensor capable of conducting glucose concentration measurements has been developed without chemical bindings. The sensing device uses a microstrip transmission line to detect variation of the glucose component of the solutions placed in a cavity under it. The uniform and concentrated electric field distribution results in an accurate and sensitive measurement of the absorption frequency shift in the frequency response of the sensor. The sensor was fabricated on a FR4 substrate for low-cost purpose. The shift in the absorption frequency of the device was measured in the frequency range between 4.8 GHz and 5.7 GHz using solutions with different glucose concentrations in two ranges: (a) high concentration from 1000 mg dl−1 to 8000 mg dl−1 and (b) low concentration from 100 mg dl−1 to 300 mg dl−1. The experimental results showed a high sensitivity of 0.32 MHz (mg dl−1)−1 for the low concentrations in terms of absorption frequency.
Exploiting gold nanoparticles for diagnosis and cancer treatments
Authors: D’Acunto Mario , Cioni Patrizia , Gabellieri Edi , Presciuttini Gianluca 
Published: February 2021

Abstract
Gold nanoparticles (AuNPs) represent a relatively simple nanosystem to be synthesised and functionalized. AuNPs offer numerous advantages over different nanomaterials, primarily due to highly optimized protocols for their production with sizes in the range 1–150 nm and shapes, spherical, nanorods (AuNRs), nanocages, nanostars or nanoshells (AuNSs), just to name a few. AuNPs possess unique properties both from the optical and chemical point of view. AuNPs can absorb and scatter light with remarkable efficiency. Their outstanding interaction with light is due to the conduction electrons on the metal surface undergoing a collective oscillation when they are excited by light at specific wavelengths. This oscillation, known as a localized surface plasmon resonance, causes the absorption and scattering intensities of AuNPs to be significantly higher than identically sized non-plasmonic nanoparticles. In addition, AuNP absorption and scattering properties can be tuned by controlling the particle size, shape, and the local refractive index near the particle surface. By the chemical side, AuNPs offer the advantage of functionalization with therapeutic agents through covalent and ionic binding, which can be useful for biomedical applications, with particular emphasis on cancer treatments. Functionalized AuNPs exhibit good biocompatibility and controllable distribution patterns when delivered in cells and tissues, which make them particularly fine candidates for the basis of innovative therapies. Currently, major available AuNP-based cancer therapeutic approaches are the photothermal therapy (PTT) or photodynamic therapy (PDT). PTT and PDT rely upon irradiation of surface plasmon resonant AuNPs (previously delivered in cancer cells) by light, in particular, in the near-infrared range. Under irradiation, AuNPs surface electrons are excited and resonate intensely, and fast conversion of light into heat takes place in about 1 ps. The cancer cells are destroyed by the induced hyperthermia, i.e. the condition under which cells are subject to temperature in the range of 41 °C–47 °C for tens of minutes. The review is focused on the description of the optical and thermal properties of AuNPs that underlie their continuous and progressive exploitation for diagnosis and cancer therapy.
Enhanced interfacial reaction of silicon carbide fillers onto the metal substrate in carbon nanotube paste for reliable field electron emitters
Authors: Go Eunsol , Kim Jae-Woo , Lee Jeong-Woong , Ahn Yujung , Jeong Jin-Woo , Kang Jun-Tae , Park Sora , Yun Ki Nam , Kim Seong Jun , Kim Sunghee , Yeon Ji-Hwan , Song Yoon-Ho 
Published: February 2021

Abstract
Adhesion of carbon nanotube (CNT) onto a cathode substrate is very crucial for field electron emitters that are operating under high electric fields. As a supporting precursor of CNT field emitters, we adopted silicon carbide (SiC) nano-particle fillers with Ni particles and then enhanced interfacial reactions onto Kovar-alloy substrates through the optimized wet pulverization process of SiC aggregates for reliable field electron emitters. As-purchased SiC aggregates were efficiently pulverized from 20 to less than 1 micro-meter in a median value (D50). CNT pastes for field emitters were distinctively formulated by a mixing process of the pulverized SiC aggregates and pre-dispersed CNTs. X-ray photoelectron spectroscopy studies showed that the optimally pulverized SiC-CNT paste-emitter had a stronger Si 2p3/2 signal in the Ni2Si phase than the as-purchased one. The Si 2p3/2 signal would represent interfacial reaction of the SiC nano-particle onto Ni from the CNT paste and the Kovar substrate, forming the supporting layer for CNT emitters. The optimal paste-emitter even in a vacuum-sealed tube exhibited a highly reliable field emission current with a high current density of 100 mA cm−2 for over 50 h along with good reproducibility. The enhanced interfacial reaction of SiC filler onto the metal substrates could lead to highly reliable field electron emitters for vacuum electronic devices.
A remote-controlled detector system with Geiger–Müller counter
Authors: Le Anh Duc , Nguyen Quoc B , Tran Ngoc Chat , Nguyen Ngoc Hung 
Published: February 2021

Abstract
In Vietnam, nuclear physics is a fundamental part of the national curriculum for physics. However, due to a lack of experimental apparatus (detectors, radioactive sources, etc) at most of the schools, the majority of students do not have opportunities to experience the phenomena behind the concepts. Moreover, safety is another major concern when conducting experiments on radioactive materials. We have developed a system of remote-controlled detector which allows students and teachers to conduct radioactive experiments safely. The system is assembled from many accessible components with reasonable prices such as Geiger–Müller counter, Arduino board, distance sensor, Wi-Fi transceiver receiver model board and stepper motor, etc. These components are widely available in the market.
Influence of segmentation accuracy in structural MR head scans on electric field computation for TMS and tES
Authors: Rashed Essam A , Gomez-Tames Jose , Hirata Akimasa 
Published: February 2021

Abstract
In several diagnosis and therapy procedures based on electrostimulation effect, the internal physical quantity related to the stimulation is the induced electric field. To estimate the induced electric field in an individual human model, the segmentation of anatomical imaging, such as magnetic resonance image (MRI) scans, of the corresponding body parts into tissues is required. Then, electrical properties associated with different annotated tissues are assigned to the digital model to generate a volume conductor. However, the segmentation of different tissues is a tedious task with several associated challenges specially with tissues appear in limited regions and/or low-contrast in anatomical images. An open question is how segmentation accuracy of different tissues would influence the distribution of the induced electric field. In this study, we applied parametric segmentation of different tissues to exploit the segmentation of available MRI to generate different quality of head models using deep learning neural network architecture, named ForkNet. Then, the induced electric field are compared to assess the effect of model segmentation variations. Computational results indicate that the influence of segmentation error is tissue-dependent. In brain, sensitivity to segmentation accuracy is relatively high in cerebrospinal fluid (CSF), moderate in gray matter (GM) and low in white matter for transcranial magnetic stimulation (TMS) and transcranial electrical stimulation (tES). A CSF segmentation accuracy reduction of 10% in terms of Dice coefficient (DC) lead to decrease up to 4% in normalized induced electric field in both applications. However, a GM segmentation accuracy reduction of 5.6% DC leads to increase of normalized induced electric field up to 6%. Opposite trend of electric field variation was found between CSF and GM for both TMS and tES. The finding obtained here would be useful to quantify potential uncertainty of computational results.
Diagnostics of laser-produced Mg plasma through a detailed collisional radiative model with reliable electron impact fine structure excitation cross-sections and self-absorption intensity correction
Authors: Baghel S S , Gupta S , Gangwar R K , Srivastava R 
Published: February 2021

Abstract
A detailed fine-structure resolved collisional radiative model is developed to investigate the laser-produced Mg plasma. The dominant processes linked with the electron impact excitation and de-excitation have been considered explicitly in a very reliable and consistent manner in the present model. The required electron impact excitation cross-sections of Mg for the large number of transitions from the ground state 3s2 (J = 0) to the 3s3p, 3s4s, 3s3d, 3s4p, 3s5s, 3s4d, 3s5p, 3s6s, 3s5d, and 3s6p excited states and from 3s3p manifolds to the other fine-structure levels of 3s4s, 3s3d, 3s5s, 3s4d, 3s6s, and 3s5d configurations are obtained using the fully relativistic distorted wave approach. To ensure the accuracy of our calculations, where available, the oscillator strengths and cross-sections are compared with previous measurements and other calculations. Further, plasma diagnostics are carried out by coupling the present collisional radiative model with the laser-induced breakdown spectroscopy measurements reported by Delserieys et al (2009 J. Appl. Phys., 106, 083304). Five measured intense emission lines of Mg viz 383.3, 470.3, 517.8, 552.8, and 571.1 nm are used and corrected through the self-absorption to extract the plasma parameters i.e. electron temperature and electron density. The obtained plasma parameters at different delay times ranging from 100–700 ns are compared with the results of Delserieys et al (2009 J. Appl. Phys., 106, 083304) that were estimated using the Thomson scattering and Boltzmann plot approaches.
Enhancing the performance of photodetectors based on ZnO nanorods decorated with Ag nanoparticles
Authors: Dinh Tan Muon , Huynh Hung Quang , Mai Thi My Nhung , Truong Hong Sang , Luong Hoai Nhan , Nguyen Ngoc Phuong , Tran Cong Khanh , Phan Bach Thang , Dang Vinh Quang 
Published: February 2021

Abstract
Zinc oxide nanorods (ZnO NRs) were modified by decorating with silver (Ag) nanoparticles to enhance visible absorption. The morphology, structure and optical properties of the modified ZnO NRs were investigated by scanning electron microscopy, x-ray diffraction and UV–vis absorption spectroscopy. Photodetectors (PDs) based on the modified ZnO NRs successfully detected visible radiation. The result showed high performance of the visible sensor (λ = 400 nm) with a maximum responsivity of 46 mA W−1. The photoconductive gain of Ag/ZnO NR-based PDs was 5.8 times higher than that of pure ZnO NR ones. With their enhanced visible absorption, the multi-modified ZnO NRs are suitable for practical applications, especially in optoelectronic devices operating in the visible region.
Stability model of bulk HTS field pole of a synchronous rotating machine under load conditions
Authors: Watasaki Masahiro , Izumi Mitsuru , Miki Motohiro , Bocquel Clement , Shaanika Erasmus , Yamaguchi Kota , Ida Tetsuya , Englebretson Steven , Chin Robert , Morita Mitsuru , Teshima Hidekazu 
Published: February 2021

Abstract
High-temperature superconducting (HTS) bulks act as magnets with trapped magnetic flux and potentially exhibit high magnetic field performance, superior to that of permanent magnets. In the fourth industrial revolution, HTS magnets could potentially facilitate the development of highly efficient and lightweight motors and generators for propulsion. To evaluate and verify the durability of HTS rotating machines, we developed a radial-gap-type rotating machine whose field-pole modules comprised HTS bulks. We examined the stability of the trapped magnetic flux of the field poles during the machine’s operation. The rotating machine was operated with different loads, and the magnetic field associated with the trapped flux of the HTS bulks was analyzed. The analysis was performed for different loads and revolution speeds, and the long-term operation for a constant load was investigated. The trapped flux of the bulk field poles and the output power were observed to be almost constant for over 360 h, and the HTS bulk magnet’s surface temperature hardly changed below 40 K during the machine’s operation. Furthermore, the magnetic flux decay determined from magnetic flux measurements before and after a load test was less than 1%. An analysis of the magnetic field distribution around the HTS bulk revealed that the transverse magnetic flux flowed through the magnetic guide of the rotor core. These results indicate the potential synchronous machine application of the high trapped magnetic flux of the field-pole modules accumulated by the appropriate positioning the HTS bulks three-dimensionally.
A nonlinear interaction between SU(1,1) quantum system and a three-level atom in different configurations with damping term
Authors: Obada A-S F , Ahmed M M A , Abu-Shady M , Khalil E M , Mohamed A-B A , Habeba H F 
Published: February 2021

Abstract
The effect of nonlinear medium and phase damping is investigated on an atom of three levels in different forms interacting with the SU(1,1) Lie algebra. The SU(1,1) system starts the interaction from the Perelomov coherent state, while the atom starts the interaction from excited-most state. The time dependent wave function is calculated by using the Schrödinger equation. The density matrix is obtained. The influences of damping, nonlinearity (Kerr-like medium), Perelomov coherent parameter and the Bargmann index on some non-classical properties, such as: revivals-collapses phenomenon, entanglement and atomic variables squeezing, are investigated.
Tunable erbium doped fiber laser based on a spherical micro-ball lens as a Fabry–Perot interference filter
Authors: Bender-Pérez C E , Castillo-Guzmán A A , Alvarez-Tamayo R I 
Published: February 2021

Abstract
The tunable wavelength emission of an erbium doped fiber laser using a Fabry–Perot interference filter based on a fiber micro-ball lens (MBL) with a spherical shape is experimentally demonstrated. The filter is formed at the tip of a single-mode fiber by controlled electric arc discharge. The filter consists of a fiber MBL with a radius of 152.7 µm and a flat-convex mirror. A tunable single laser emission range of 1556.85–1569.72 nm is obtained when the mirror moves perpendicular to the fiber. Dual-wavelength laser emission with a separation of ∼12.9 nm corresponding to the free spectral range of interference modulation is obtained within the single laser wavelength tuning limits. The laser line exhibits full width at maximum half of 0.1 nm. The stability of the laser emission is also discussed. The use of a reliable tunable spectral filter for dual-wavelength emission and single tuning is demonstrated in the fiber laser’s design. The proposed spectral filter configuration can be useful in different research areas, such as the coherent development of light sources, optical communications, and optical instrumentation.
Observation of strong mode coupling in multimode step index silica optical fibers with fluorinated thermoplastic polymer cladding
Authors: Savović S , Djordjevich A 
Published: February 2021

Abstract
Using the power flow equation, the state of mode coupling in step index multimode silica optical fiber with fluorinated thermoplastic polymer cladding is investigated in this work. Coupling coefficient is determined by employing our previously reported calculation method. The silica optical fiber with fluorinated thermoplastic polymer cladding shows much stronger mode coupling than the all plastic-clad silica fibers investigated in earlier works. Consequently, it takes much shorter fiber length for the equilibrium mode distribution or steady state distribution to develop (faster launch beam narrowing), which is of great interest in employing silica optical fiber with fluorinated thermoplastic polymer as a part of telecommunication, medical and sensory system.
Effects of initial velocity on the sinking of ilmenite-bearing cumulates in the early lunar mantle: Insight from the theory of Rayleigh-Taylor instability
Authors: Yu Shuo-Ran , Zhang Xiao-Ping 
Published: February 2021

AbstractThe early lunar mantle overturn, associated with the sinking of the dense ilmenite-bearing cumulate (IBC) crystallized at the shallow lunar mantle, provides satisfactory explanations for the origination of high-Ti basalt, the abnormally strong magnetic field between ∼ 3.9 and ∼ 3.6 Ga and the low-viscosity zone in the deep lunar mantle, but still poses a debate regarding the initial state of IBC in the early lunar mantle. If the sinking of IBC initiated before the end of lunar magma ocean crystallization, the solidified IBC can acquire a greater thickness and a higher initial velocity at the IBC-mantle boundary. The variation of initial velocity can affect the strain rate of IBC and, correspondingly, the dislocation creep components at the shallow lunar mantle. In this work, we analyze the effects of initial velocity on the dynamics of early lunar mantle by using the theory of Rayleigh-Taylor instability. To couple the effects of diffusion creep and dislocation creep for all major minerals in the lunar mantle, we exploit an improved Minimized Power Geometric (IMPG) model and isostress mixing model to characterize the upper limit and lower limit for the viscosity of the lunar mantle comprising four major minerals, i.e. olivine, orthopyroxene, clinopyroxene and ilmenite. The modeling results suggest that a high initial velocity, in any case, can shorten the onset time, tending to promote the early lunar mantle overturn even in a rheologically-strong lunar mantle. The effect of initial velocity on the overturn wavelength shows a strong dependence on the rheological mixing model. For the isostress mixing model, the increase of initial velocity tends to elongate the overturn wavelength. For the IMPG mixing model, the overturn wavelength is insensitive to the variation of initial velocity. As the actual lunar mantle rheology sandwiches between the rheologies predicted by isostress mixing model and IMPG model, it can be anticipated that the increase of initial velocity tends to elongate the overturn wavelength. In consideration of the importance of the initial velocity on the dynamics of early lunar mantle, future investigations should focus on the dynamics of the solid IBC in the solidifying lunar magma ocean.