bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrical properties of tissues from a microscopic model of confined electrolytes
Authors: Solis Francisco J , Jadhao Vikram 
Published: April 2023

Abstract

Objective. In the presence of oscillatory electric fields, the motion of electrolyte ions in biological tissues is often limited by the confinement created by cell and organelle walls. This confinement induces the organization of the ions into dynamic double layers. This work determines the contribution of these double layers to the bulk conductivity and permittivity of tissues. Approach. Tissues are modeled as repeated units of electrolyte regions separated by dielectric walls. Within the electrolyte regions, a coarse-grained model is used to describe the associated ionic charge distribution. The model emphasizes the role of the displacement current in addition to the ionic current and enables the evaluation of macroscopic conductivities and permittivities. Main results. We obtain analytical expressions for the bulk conductivity and permittivity as a function of the frequency of the oscillatory electric field. These expressions explicitly include the geometric information of the repeated structure and the contribution of the dynamic double layers. The low-frequency limit of the conductivity expression yields a result predicted by the Debye permittivity form. The model also provides a microscopic interpretation of the Maxwell–Wagner effect. Significance. The results obtained contribute to the interpretation of the macroscopic measurements of electrical properties of tissues in terms of their microscopic structure. The model enables a critical assessment of the justification for the use of macroscopic models to analyze the transmission of electrical signals through tissues.
A few-shot electromechanical impedance monitoring method based on a modified prototype network
Authors: Du Fei , Wu Shiwei , Weng Jiexin , Zhang Xuan , Xu Chao , Su Zhongqing 
Published: April 2023

Abstract
Bolt loosening monitoring is of great significance to warrant the reliability and safety of bolted structures. The electromechanical impedance (EMI)-based evaluation is effective to perceive bolt loosening. However, EMI signals are highly prone to contamination by temperature fluctuation. Deep learning (DL) based EMI is a promising technique for accurate damage detection in the temperature variation environment. However, DL needs a lot of data to train, which is usually very difficult to collect sufficient structural damage data in real word scenarios. This paper proposed a few-shot EMI monitoring method based on a modified prototype network for bolt looseness detection under temperature varying environment. The approach features a conversion method of the impedance signal to image based on the Hank matrix. A modified prototype network is then developed. An experimental study was carried out on a bolted joint. EMI signals under different bolt loosening conditions were measured in a temperature variation environment. An impedance analyzer and a self-made small lightweight monitoring device were both used to measure the EMI signals to test the cross domain scenario. The proposed method was compared with the transfer learning methods and other typical few-shot learning methods. The experiment results show that the proposed few-shot EMI method can obviously improve the monitoring accuracy of bolt loosening with few samples.
Ricci solitons on general relativistic spacetimes
Authors: Suh Young Jin , Chaubey Sudhakar Kumar 
Published: April 2023

Abstract
The main aim of this manuscript is to characterize the general relativistic spacetimes with Ricci and gradient Ricci solitons. It is proven that if the metric of a general relativistic spacetime (M
4, ξ) admitting a special unit timelike vector field ξ is an almost Ricci soliton (g, ξ, λ), then (M
4, ξ) is a perfect fluid spacetime, and almost Ricci soliton (g, ξ, λ) on (M
4, ξ) becomes shrinking Ricci soliton. We prove that a general relativistic perfect fluid spacetime equipped with a special unit timelike vector field together with a Ricci soliton is an Einstein spacetime. In this sequel, we also prove that the Ricci soliton is shrinking, soliton vector field is Killing and the scalar curvature of the perfect fluid spacetime is constant. It is proven that a general relativistic perfect fluid spacetime together with a Ricci soliton is a generalized Robertson-Walker (GRW) spacetime. The existence of gradient Ricci solitons on general relativistic spacetimes are established. We also construct a non-trivial example of general relativistic spacetime equipped with a special unit timelike vector field, and verify some of our theorems.
Monitored recurrence of a one-parameter family of three-state quantum walks
Authors: Štefaňák Martin 
Published: April 2023

Abstract
Monitored recurrence of a one-parameter set of three-state quantum walks on a line is investigated. The calculations are considerably simplified by choosing a suitable basis of the coin space. We show that the Polya number (i.e. the site recurrence probability) depends on the coin parameter and the probability that the walker is initially in a particular coin state for which the walk returns to the origin with certainty. Finally, we present a brief investigation of the exact quantum state recurrence.
Angular momentum sensitivity of a MEMS gyroscope for condensed matter systems
Authors: Jeong Jinhoon , Suh Junho , Choi Hyoungsoon 
Published: April 2023

Abstract
The angular momentum carries crucial information on the physical nature of quantum matter. We propose and analyze MEMS gyroscope techniques suitable for measuring the angular momentum of mesoscopic quantum matter specimens at low temperatures. We bear in mind that it is not always possible to implement mode-matched gyroscopes, which we will refer to as degenerate gyroscopes, for the maximal signal sensitivity for these applications due to the constraints given by the cryogenic environment and the types of samples available for experiments. Because the analysis of non-degenerate gyroscopes in the literature is somewhat limited, we analyze and compare the ultimate angular momentum sensitivity of both degenerate and non-degenerate gyroscopes under amplitude and frequency modulation operation. Calculation based on our prototype device shows that the frequency modulation extends the operational range and improves sensitivity at low temperatures.
A non-linear triangular split-ring based metaresonator for targeted scanning at 1.5T MRI
Authors: Das Priyanka , Gupta Jegyasu , Sikdar Debabrata , Bhattacharjee Ratnajit 
Published: April 2023

Abstract
In magnetic resonance imaging (MRI), RF signals are initially transmitted to stimulate the body protons which eventually release the electromagnetic energy while returning back to their original states. The image resolution and scanning efficiency of MRI can be improved by enhancing the magnetic fields received from the patient’s body using metamaterials. The major limitation of linear metamaterials is that they amplify RF magnetic fields both during transmission and reception phases. This requires modification of the RF excitation pulses during the transmission phase. Further, local increase of transmitted power poses a potential threat of tissue-heating and high specific absorption rate (SAR) values in addition to perturbing the transmit field homogeneity. In order to circumvent these problems, we propose a self-adaptive metaresonator which has the capability of self-detuning itself during transmission of RF pulses during MRI scans. A triangular split-ring based metaresonator is designed for maximum thirty-fold SNR improvement in 1.5T MRI. Switching diodes have been employed for switching on and off the magnetic field enhancement by the metaresonator. During transmission phase when the switching diodes get turned on, the metaresonator is detuned. During reception phase when the switching diodes get turned off, the metaresonator is tuned to 63.8 MHz which is the Larmor frequency of 1.5T MRI. The proposed metaresonator is thin and compact which enables its easy placement in the multi-element arrays of clinical MRI.
Physical properties of elastically and thermodynamically stable magnetic AcXO3 (X = Cr, Fe) perovskite oxides: a DFT investigation
Authors: Munir Junaid , Iftikhar M Khuram , Jamil M Imran , Din Moeen Ud , Alshahrani Thamraa , Elsaeedy H I , Ain Quratul 
Published: April 2023

Abstract
Spin-polarized calculations of mechanical, electronic structure, phonon, optical and magnetic properties of AcXO3 (X = Cr, Fe) perovskite oxides (POs) has been computed using the full-potential linearized augmented plane wave method. The modified Becke Johnson (mBJ) approximation has been utilized for exchange-correlation potential and implemented in the WIEN2k code. The negative values of formation energy and the positive fRequencies of the phonon modes show the stability of studied perovskite oxides. The mechanical stability is confirmed through the elastic parameters such as shear modulus (G), Bulk modulus (B), Poisson ratio (ν) and Cauchy pressure. The semiconductor nature with an indirect bandgap is observed for both compounds in both spin channels. The computed electron density contour plot describes the bonding nature of both compounds. The magnetic moments are calculated, which show the major involvement of Fe and Cr atoms in the overall magnetism of studied compounds. The optical response is also evaluated, showing the maximum absorption in the ultraviolet region. The overall analysis of the calculated properties shows that the studied oxide perovskites are suitable for spintronic and optoelectronic applications.
Geodesic angular momentum
Authors: Tachibana Akitomo 
Published: April 2023

Abstract
Translational symmetry gives rise to rotational symmetry in general relativistic symmetry. This is an inconceivable fact according to conventional common sense, but the proof is given. Could the converse also be true? No, a counter-example is given. There is rotational symmetry that does not require translational symmetry, which does not give rise to translational symmetry even in general relativistic symmetry. The latter fact of course does not defy conventional common sense. Rotational symmetry conserves angular momentum. Antisymmetric tensor that vanishes by covariant differentiation is here defined geodesic angular momentum tensor. Killing vector due to rotational symmetry exists. We show a vierbein formalism for discussing translational symmetry and rotational symmetry in the same footing. We present a simple model that reveals how the internal spin of a Dirac particle contributes to the momentum tensor as vorticity, and how this vorticity is transformed into spin by the integration of the geodesic angular momentum tensor.
Shot-by-shot stability of the discharge produced plasmas in suitably shaped capillaries
Authors: Arjmand S. , Anania M.P. , Biagioni A. , Ferrario M. , Del Franco M. , Galletti M. , Lollo V. , Pellegrini D. , Pompili R. , Zigler A. 
Published: April 2023

Abstract
Compact accelerator machines are capable of producing accelerating gradients in the GV/m
scale, which is significantly higher than the MV/m scale of conventional machines. As accelerators
are widely used in many fields, such as industrial, research institutes, and medical applications,
the development of these machines will undoubtedly have a profound impact on people's daily
lives. SPARC_LAB, a test facility at INFN-LNF (Laboratori Nazionali di Frascati), is focused on
enhancing particle accelerator research infrastructure using innovative plasma acceleration
concepts. Within SPARC_LAB, we utilize plasma-filled capillaries with lengths of up to tens of
centimeters. However, the plasma formation process is critical to ensure proper oversight of the
plasma properties, which subsequently affects the dynamics of the electron bunch to be
accelerated. One of the most critical points that significantly affects the properties of the
electron beam passing through the plasma source is the shot-by-shot stability of the plasma
density along the longitudinal dimension of the plasma-discharge capillary. Therefore, this paper
aims to investigate the shot-by-shot stability of the plasma density during discharge,
contributing to further advancements in the field of plasma acceleration.
Reduction potentials for particulate emissions from household energy in India
Authors: Lam Nicholas L , Goel Varun , Blasdel Max , Xu Li , Ruiz-Mercado Ilse , Ozaltun Bora , Aoudi Lama , Whitacre James V , Bond Tami C 
Published: April 2023

Abstract
Household access to clean energy is a priority for public health and the environment in low- and middle-income countries. However, past illustrative studies have explored benefits of replacing all polluting energy sources, a transition that is only theoretically possible. Factors that limit achievement of the entire theoretical reduction potential should be explored to inform programmatic decision making. We propose a hierarchy of reduction potentials for emissions from household energy, representing different implementation barriers. Following similar work in renewable energy, we propose four categories of reduction potentials beyond the theoretical maximum: distributional, technical, economic, and market. We apply this framework to household energy emissions using a high-resolution spatiotemporal emission inventory of India, a country chosen for its data availability and level of interest in mitigation. We explore distributional potential using distance from urban areas, technical potential by attributing emissions to energy services, and economic potential with a village- level proxy for likelihood of program success. For distributional potential (spatial accessibility), we find that applying reduction programs within 5 km of urban centers would achieve 36%–78% of the theoretical potential across seven regions in India; extension to 10 km yields reductions of 63%–90%. Technical and economic reduction potentials differ most greatly from theoretical potential in regions that contribute the most to national emissions. Even if some of the relationships underlying emission causes are not completely known, reflecting the factors that affect transitions can inform practitioners and programs seeking to scale and deliver clean energy solutions. We assert that including these important influences should be a goal of emission inventory development, beyond the simple quantification of baseline emissions.
Electronic structures near unmovable nodal points and lines in two-dimensional materials
Authors: Damljanović V , Lazić N 
Published: April 2023

Abstract
Unmovable nodal points (UNPs) and lines (UNLs) are band crossings whose positions in the Brillouin zone are unaltered by symmetry preserving perturbations. Not only positions but also the band structure in their vicinity are determined by the little group of wave vectors and its irreducible (co)representations. In this paper, we give the full set of electronic dispersions near all UNPs and UNLs in non-magnetic quasi two-dimensional (2D) materials, both with and without spin–orbit coupling (SOC). Analysis of all layer gray single and double groups gives nineteen different quasiparticles, the great majority of which are unavoidable for a 2D material that belongs to a certain layer group. This includes Weyl and Dirac nodal lines, dispersions with quadratic or cubic splitting, anisotropic Weyl and Dirac cones, whose orientation can be varied by e.g. strain etc. We indicated quasiparticles that are robust to SOC. For convenience, our results are concisely presented graphically—as a map, not in a tabular, encyclopedia form. They may be of use as checkpoints and/or for fitting experimentally (via e.g. ARPES) and numerically obtained electronic band structures data, as well as for deeper theoretical investigations.
Dimensional-transformation of hexagonal antimonene nanosheets through the manipulation of reduction kinetics
Authors: Sun Haibin , Zheng Wenrui , Liu Congcong , Li Xiangdong , Chu Xinyu , Wang Shiran , Liu Shenghong , Xie Wenhe 
Published: April 2023

Abstract
Antimonene (Sb) has been widely studied owing to its high carrier mobility, high thermal conductivity, and tunable electronic properties. Conventional synthetic methods for antimonene nanosheets (Sb-NSs) are more complex and multi-step reactions, mainly including the epitaxial growth method, mechanical peeling method, electrochemical separation method, and liquid-phase separation method. Here, we report a simple method for the synthesis of Sb-NSs on Ni foam from two-dimensional (2D) nanosheets to one-dimensional (1D) nanowires via hydrothermal method. The fabricated hexagonal Sb-NSs exhibit a transverse scale of 400 nm and a thickness of approximately 50 nm. When evaluated as anode materials for lithium storage, hexagonal Sb-NSs deliver a high reversible capacity of 870.3 mAh g−1 at 0.2 A g−1 and a reversible capacity of 375 mAh g−1 at 0.2 A g−1 after 60 cycles. As a result, the successful preparation of dimensional-switching Sb-NMs provides a new class of 2D materials for LIBs.
Novel approach to utilise highly conductive but electrochemically unstable current collector materials in textile supercapacitor electrodes
Authors: Luís Paulo , Southee Darren , Weaver George W , Wijayantha Upul 
Published: April 2023

Abstract
Metal-based materials, such as silver or copper, are highly desired as current collector materials for flexible energy storage due to their excellent electrical properties but lack the long-term operational electrochemical stability. Herein we report a method to prevent the corrosion of such materials, while fully exploiting their electrical properties. This was achieved by covering the current collector with an electrochemically stable conductive carbon-based layer. The barrier layer allows the flow of charge between the electrically conductive elements of the textile composite electrodes, while protecting the current collector from contacting the electrolyte. The areal power and energy densities obtained after 1000 bending cycles were 29.88 and 0.01 mWh cm−2, respectively, with no evident degradation. Additionally, patterned current collectors were designed to deposit lower quantities of ink, without detriment to electrochemical performance. After 1000 bending cycles, the textile composite supercapacitors (TCSs) having 50% less current collector material demonstrated an areal power and energy density of 28.08 and 0.01 mWh cm−2, respectively. The proposed strategy is essential in enabling the utilisation of highly conductive metal-based inks, improving the rate capabilities and long-term operation of wearable energy storage devices, while maximising specific power and energy densities of TCSs, and decreasing the manufacturing cost.
Optical simulations and optimization of perovskite/CI(G)S tandem solar cells using the transfer matrix method
Authors: Bojar Aleksandra , Micha Daniel , Giteau Maxime , Ruiz-Preciado Marco A , Paetzold Ulrich W , Simor Marcel , Gevaerts Veronique S , Carron Romain , Medjoubi Karim , Collin Stéphane , Naghavi Negar , Guillemoles Jean-François , Schulz Philip 
Published: April 2023

Abstract
In this work we employ the transfer matrix method for the analysis of optical materials properties to simulate and optimize monolithic tandem solar cell devices based on CuIn1−x
Ga
x
Se2, CI(G)S, and perovskite (PVK) absorbers. By finding models that fit well the experimental data of the CI(G)S solar cell, the semitransparent perovskite solar cell (PSC) and the PVK/CI(G)S monolithic tandem solar cell, we were able to perform a detailed optical loss analysis that allowed us to determine sources of parasitic absorption. We found better substitute materials for the transport layers to increase the power conversion efficiency and, in case of semitransparent PSCs, sub-bandgap transmittance. Our results set guidelines for the monolithic PVK/CI(G)S tandem solar cells development, predicting an achievable efficiency of 30%.
Simulation of new thin film Zn(O,S)/CIGS solar cell with bandgap grading
Authors: Elhady Fady , M Abdolkader Tarek , Fedawy Mostafa 
Published: April 2023

Abstract
Copper-Indium-Gallium-diSelenide (CIGS) thin film solar cell is a promising candidate for energy harvesting because of its high absorption coefficient and low cost compared to silicon-based solar cells. Absorber layer bandgap grading is a suitable method to improve CIGS thin film solar cell performance. Bandgap grading leads to a decrease in the recombination rate at the rear surface, which increases the open circuit voltage. Furthermore, bandgap grading improves the short circuit current due to the enhancement of collection probability. This paper introduces various routes for improving the performance of thin film CIGS solar cells by using bandgap grading. As a first step, both the bandgap energy and the thickness of the CIGS absorber layer of a uniform bandgap profile are optimized to get the best performance. Simulation is performed using SCAPS software and optimization results show that CIGS absorber layer with a bandgap of 1.2 eV and a thickness of 0.7 μm achieves a 22.48% efficiency. Then, bandgap grading with a parabolic distribution of various profiles is investigated and compared. It is found that with a parabolic double bandgap grading profile, which is a combination of front and back grading, an efficiency of up to 24.16% is achieved. This improvement is obtained using a gallium composition ratio of 0.1 for the minimal bandgap at 0.1 μm and 0.13 μm from the back contact and front contact, respectively. This result represents a 7.47% improvement compared to the baseline structure of a CIGS solar cell.
Policy approaches to mitigate in-use methane emissions from natural gas use as a marine fuel
Authors: Laskar Imranul I , Giang Amanda 
Published: April 2023

Abstract
Unregulated in-use methane emissions (or methane slip) can reduce or even eliminate the overall climate benefits of using liquefied natural gas as a marine fuel. We conduct critical review and expert interviews to identify methane slip mitigation measures, and then identify and evaluate potential policy instruments that could incentivize their uptake while considering the shipping sector’s climate targets. We find that regulatory instruments are expected to perform the best across a range of criteria when they are at the global level, include methane on a CO2-equivalent and lifecycle basis, promote polycentric approaches to climate governance, and allow flexibility in how the industry incorporates decarbonization measures. Market-based approaches and informational governance policies complement regulatory instruments by improving cost-effectiveness and increasing the availability of relevant information on emissions mitigation. The urgency and scale of shipping climate targets underscore the need for policy approaches that support planning for long-term decarbonization pathways and that can avoid locking into fossil-carbon intensive systems.