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Generalized ellipsometry measurements are used to extract the complex dielectric function (ε = ε 1 + i ε 2) spectra of GdScO3 single crystals over the 0.7–8.5 eV photon energy range. GdScO3 is a wide bandgap semiconductor with a high dielectric constant, and potential applications include replacing SiO2 in silicon-based transistors and as an epitaxial substrate for thin film growth. This work presents the anisotropic optical properties for electric fields oscillating parallel to the a-, b-, and c-crystallographic axes. A direct bandgap is identified at 6.44 eV along the direction parallel to the a-axis, with additional critical points observed at 6.74 and 7.42 eV in the same direction. Additional above gap critical point transitions are found at 6.72, 7.31, and 7.96 along the direction parallel to the b-axis and 6.83 and 8.00 eV along the direction parallel to the c-axis. [ABSTRACT FROM AUTHOR]

Generalized ellipsometry measurements are used to extract the complex dielectric function (ε = ε 1 + i ε 2) spectra of GdScO3 single crystals over the 0.7–8.5 eV photon energy range. GdScO3 is a wide bandgap semiconductor with a high dielectric constant, and potential applications include replacing SiO2 in silicon-based transistors and as an epitaxial substrate for thin film growth. This work presents the anisotropic optical properties for electric fields oscillating parallel to the a-, b-, and c-crystallographic axes. A direct bandgap is identified at 6.44 eV along the direction parallel to the a-axis, with additional critical points observed at 6.74 and 7.42 eV in the same direction. Additional above gap critical point transitions are found at 6.72, 7.31, and 7.96 along the direction parallel to the b-axis and 6.83 and 8.00 eV along the direction parallel to the c-axis. [ABSTRACT FROM AUTHOR]

To precisely investigate the electric properties and reveal the intrinsic interaction mechanisms between multiple fields in the composite magneto-electric-semiconductor shell structure, two-dimensional analyses were conducted within the framework of the third-order shear deformation theory and the coupled field theory. The governing equations for the composite piezoelectric semiconductor (PS) shell structures were derived using the principle of virtual work. Field distributions of the composite PS shell structures were obtained by expanding basic field quantities into Fourier series along the width direction and using the differential quadrature method. Prior to analysis, the convergence and correctness of the adopted method were evaluated. Several numerical examples were presented to demonstrate how magnetic manipulation can tune electrical behavior. It was found that inhomogeneous shear strain induced by applied magnetic fields is the key factor affecting potential variation in the composite PS shells. The appearance of potential barriers and wells in the composite PS shell structure with an opposite c axis is explained thoroughly. Additionally, the effect of magnetic field non-uniformity on the composite PS shell structure was investigated using an equivalent body force model, offering valuable insights for designing thin-film devices. [ABSTRACT FROM AUTHOR]

Band-tail states, i.e., charge-carrier energy states located in the bandgap at the valence and conduction band edges of amorphous materials, even though not delocalized, exhibit nonzero mobility; thus, they are expected to contribute to the charge-conduction process. A microscopic model based on hydrodynamic transport equations for unipolar conduction, including trap, band-tail, and band states, and coupled to the Poisson equation is presented here. The equations are self-consistently solved by means of a numerical procedure, and the results provide qualitative and quantitative estimates of the influence of band-tail states (namely, of their energy distribution, density, and mobility) on the carrier heating, precursor of the Ovonic threshold switch. [ABSTRACT FROM AUTHOR]

This article follows earlier studies on the physical origin of magnetic anisotropy and the means of controlling it in polynuclear transition metal complexes. The difficulties encountered when focusing a magnetic field on a molecular object have led to consider the electric field as a more appropriate control tool. It is therefore fundamental to understand what governs the sensitivity of magnetic properties to the application of an electric field. We have already studied the impact of the electric field on the isotropic exchange coupling and on the Dzyaloshinskii–Moriya interaction (DMI). Here, we focus on the symmetric exchange anisotropy tensor. In order to obtain significant values of anisotropic interactions, we have carried out this study on a model complex that exhibits first-order spin–orbit coupling. We will show that (i) large values of the axial parameter of symmetric exchange can be reached when close to the first-order spin–orbit coupling regime, (ii) both correlated energies and wave functions must be used to achieve accurate values of the symmetric tensor components when the DMI is non-zero, and (iii) finally, an interferential effect between the DMI and the axial parameter of symmetric exchange occurs for a certain orientation of the electric field, i.e., the latter decreases in magnitude as the former increases. While DMI is often invoked as being involved in magneto-electric coupling, isotropic exchange and the symmetrical anisotropic tensor also contribute. Finally, we provide a recipe for generating significant anisotropic interactions and a significant change in magnetic properties under an electric field. [ABSTRACT FROM AUTHOR]

The quantum Drude oscillator (QDO) model has been widely used as an efficient surrogate to describe the electric response properties of matter as well as long-range interactions in molecules and materials. Most commonly, QDOs are coupled within the dipole approximation so that the Hamiltonian can be exactly diagonalized, which forms the basis for the many-body dispersion method [Phys. Rev. Lett. 108, 236402 (2012)]. The dipole coupling is efficient and allows us to study non-covalent many-body effects in systems with thousands of atoms. However, there are two limitations: (i) the need to regularize the interaction at short distances with empirical damping functions and (ii) the lack of multipolar effects in the coupling potential. In this work, we convincingly address both limitations of the dipole-coupled QDO model by presenting a numerically exact solution of the Coulomb-coupled QDO model by means of quantum Monte Carlo methods. We calculate the potential-energy surfaces of homogeneous QDO dimers, analyzing their properties as a function of the three tunable parameters: frequency, reduced mass, and charge. We study the coupled-QDO model behavior at short distances and show how to parameterize this model to enable an effective description of chemical bonds, such as the covalent bond in the H2 molecule. [ABSTRACT FROM AUTHOR]

Copper (Cu) interconnections have been widely used in advanced electronic packaging due to their outstanding thermal and electric properties. Preparing a smooth and uniform Cu seed thin layer is one of the critical processes to obtain high-reliability Cu interconnections. The barrier layer between Cu and silicon (Si) devices is necessary to prevent the inter-diffusion between Cu and Si. However, little work has been done on the surface roughness analysis of the Cu seed layer deposited on the diffusion barrier layer. In this paper, the influences of deposition thickness, incident energy, barrier layer temperature, and surface morphology on the surface roughness of the Cu seed layer deposited on α-titanium (α-Ti) barrier layer were studied in detail by the molecular dynamics (MD). The simulation results indicated that appropriate parameters have a beneficial effect on reducing the surface roughness, and the surface morphology of the Cu seed layer strongly connects with that of the barrier layer. These results provided a foundation for optimizing the quality of the Cu seed layer. [ABSTRACT FROM AUTHOR]

ScN in the rock salt structure is a well-investigated material due to its desirable properties like the high hardness or large thermal conductivity. Recent computations by Adamski et al. [Appl. Phys. Lett. 115, 232103 (2019)] showed that ScN/GaN heterostructures exhibit an outstanding polarization gradient which would be beneficial for polarization induced electron gases. The pseudobinary semiconductor Sc x Al 1 − x N, when maintaining the cubic rock salt structure, could be beneficial for tailoring the polarization gradient using the Sc dependency of material properties. The structural properties of rs-Sc x Al 1 − x N are not fully discovered yet, thus in this work, DC-magnetron sputtered cubic rock salt Sc x Al 1 − x N thin films with 0.55 < x < 1.00 were grown and analyzed on ScN(111)/Si(111). The epitaxial relation of ScN(111) thin films on the Si(111) substrate is determined to be ScN[110] ∥ Si[100]. Furthermore, concentration dependent properties like the lattice parameter of Sc x Al 1 − x N were measured [a(ScN) = 4.50 Å, a(Sc0.55Al0.45N) = 4.30 Å] and the stress σ within the layers was determined. The crystal quality was evaluated using ω -scans, revealing FWHM = 1.14 ° for Sc0.95Al0.05N. The diameters of the columns were determined by atomic force microscopy and scanning electron microscopy and they are range from 34 to 59 nm for 0.55 < x < 1.00. At x = 0.55 , Sc x Al 1 − x N columns in the hexagonal wurtzite as well as cubic rock salt structure were detected. This information about the structural specifications of Sc x Al 1 − x N in the rock salt structure forms the basis for further investigations and experimental confirmation of the electric properties of ScN/GaN heterostructures or even a Sc x Al 1 − x N/GaN based approach for improved structures for high-electron-mobility transistors. [ABSTRACT FROM AUTHOR]

In the present investigation, we report a comparative study of structural, magnetic and electric transport properties in bulk NiFe 2 O 4 and Ni 0.7 Zn 0.3 Fe 2 O 4 ceramics. The materials were synthesized by solid state reaction method. X-ray diffraction analysis confirmed the cubic spinel structure of the ferrite samples belonging to the Fd 3 ‾ m space group. The structural analysis of the ceramics was comprehensively evaluated from Rietveld refinements of the XRD data and Raman studies. An increased grain size in the Ni 0.7 Zn 0.3 Fe 2 O 4 microstructure was noticed due to Zn substitution. Both structural and microstructural modifications led to a significant change in the magnetic and electric properties of the Ni 0.7 Zn 0.3 Fe 2 O 4 ceramic. A large increase in saturation magnetization with decreased coercivity was noticed in the Ni 0.7 Zn 0.3 Fe 2 O 4 system due to Zn substitution. DC resistivity was observed to decrease in the Zn-substituted nickel ferrite ceramic due to increased grain size and larger electron hopping between Fe3+ and Fe2+ ions, as verified by the XPS analysis. Further, a remarkable dielectric relaxation has been observed in the Ni-Zn ferrite owing to greater charge hopping and interfacial polarization. Complex impedance spectra of Ni 0.7 Zn 0.3 Fe 2 O 4 revealed evidence of surface polarization contribution with grain and grain boundary effect on the electric transport properties. [ABSTRACT FROM AUTHOR]

BaTiO 3 /Ca 10 (PO 4) 6 (OH) 2 composite ceramic is an outstanding representative of piezoelectric biomaterials, with excellent biocompatibility and piezoelectric effect, and has potential applications in the field of bone tissue repair. In this work, vat photopolymerization 3D printing technology was used to fabricate triply periodic minimal surface structure BaTiO 3 /Ca 10 (PO 4) 6 (OH) 2 composite ceramic bone tissue scaffolds with different pore sizes and porosity, and their mechanical and electrical properties were studied. First, the ceramic slurry configuration process was optimized to obtain a ceramic slurry with high solid content (45 vol%) and excellent rheological properties. Then the effect of sintering temperature on microstructure, relative density, mechanical properties, and electrical properties is discussed. The results show that when sintering at 1300 °C, the BaTiO 3 /Ca 10 (PO 4) 6 (OH) 2 composite ceramic has the highest relative density (99.18 %), the highest compressive strength (44 MPa), large relative dielectric constant (379–389), and low dielectric loss. The polarization electric field strength of the BaTiO 3 /Ca 10 (PO 4) 6 (OH) 2 composite ceramic was set to 15 kV/cm through the test of the hysteresis loop. Finally, based on multi-physics coupled finite element simulation, the effects of different porosity and different pore sizes on stress distribution and piezoelectric potential were analyzed, and the relationship between them was explored through experiments. The results show that as the porosity increases and the pore size decreases, the mechanical properties of the scaffold decrease significantly, and its compressive strength ranges between 1.67 and 4.26 MPa; as the porosity increases and the pore size increases, the piezoelectric coefficient (d 33 ) of the scaffold showed a decreasing trend, and its d 33 ranged between 2 and 9 pC/N. The mechanical and electrical properties of the scaffold meet the performance requirements of cancellous bone. In summary, this work provides a strategy for the application of customized BaTiO 3 /Ca 10 (PO 4) 6 (OH) 2 composite ceramic scaffolds in new-generation orthopedic implants. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Optical controlling of solid‐sate electric properties is emerging as a non‐contact and nondestructive avenue to optimize the physical properties of electronic and optoelectronic devices. In term of strong light‐material coupling, two‐dimensional (2D) double perovskites hold great prospects to create photo‐dielectric activities for high‐performance device applications. Here, we have achieved the photo‐excited switching and enhancement of dielectric properties in the orientational thin films of a 2D double perovskite, (C4H12N)4AgBiI8 (1, where C4H9NH3+ is isobutylammonium). It undergoes a structural phase transition at 384 K (Tc), triggered by the dynamic ordering of organic cations and tilting motion of isometallic perovskite sheets. Most notably, the orientational thin films of 1 are extremely sensitive to light illumination, of which the dielectric constants can be facilely photo‐switched between the low‐ and high‐states. During this photo‐switching process, the dielectric constants are enhanced with a magnitude up to ~350% under 405 nm, far beyond most of the inorganic phase transition counterparts. In addition, this photo‐excited switching and enhancement of dielectric response exhibits an operational stability with superior anti‐fatigue characteristics. Our work opens up a potential avenue for assembling high‐performance optoelectronic devices with the controllable physical properties. [ABSTRACT FROM AUTHOR]

A novel organic fluorescent material, namely 2,6-di([1,1'-biphenyl]-4-yl)-4-(perfluorophenyl)hepta-1,6-diene-1,1,7,7-tetracarbonitrile (DBPDT), has been synthesized and characterized in this study. Due to the special molecular packing mode in the solid state, J-aggregation, DBPDT displayed red-shifted emission compared with that in dilute solution. In this study, it was found that DBPDT showed aggregation-induced enhanced emission (AIEE) and solvatochromic properties. Assisted by quantum chemistry calculations, optical response properties to external electric field (EEF) were investigated, where it was found that external electric field (EEF) would affect the structures and optical properties of DBPDT distinctly. The optical response characteristics of DBPDT can provide an alternative structure for constructing advanced photoelectric functional materials. A novel organic fluorescent material, namely 2,6-di([1,1'-biphenyl]-4-yl)-4-(perfluorophenyl)hepta-1,6-diene-1,1,7,7-tetracarbonitrile (DBPDT), has been synthesized and characterized in this study. Assisted by quantum chemistry calculations, optical response properties to external electric field (EEF) were investigated, where it was found that external electric field (EEF) would affect the structures and optical properties of DBPDT distinctly. [ABSTRACT FROM AUTHOR]

Magnetoelectric MEMS devices, such as magnetic field sensors, may be composed of a multilayer stack as a magnetostrictive layer, which is mechanically coupled to a piezoelectric film. Good adhesion and a stable rigid interface have to be maintained for such a sensor. Certain electric and magnetic properties, especially the magnetostriction, have to reach sufficiently high values, which can be achieved by selected phases or mixtures of phases. In this study, Co / Fe multilayers with varied bilayer periods are deposited onto AlN or S c 0.14 A l 0.86 N coated Si substrates by DC magnetron sputtering with the optional insertion of a 5 nm thick adhesion layer of Cr or Zr to investigate its influence on the formation of the desired mixture of bcc and fcc C o 0.7 F e 0.3 phases, which are expected to yield a high magnetostrictive strain, after an RTA at 800 °C. A qualitative phase analysis is made by XRD in Bragg-Brentano geometry and shows that the bcc + fcc mixture can be achieved with a Cr interlayer. A sharp, void free, and undamaged interface for that case was observed in SEM images of cross sections prepared with FIB. [ABSTRACT FROM AUTHOR]

The utilization of multiple dielectric materials is an effective way to improve the energy storage performance of dielectric thin films. However, the heterointerfaces are the underbelly of multilayer dielectric thin films, which often causes defect-induced breakdown. The adaptive anodizing method was proposed to optimize dielectric heterointerface. The single anodization Al2O3/Ba0.5Sr0.5TiO3/Al2O3 (SAB) thin films were fabricated by anodizing Al/Ba0.5Sr0.5TiO3/Al thin films under the high electric field. The Al2O3/Ba0.5Sr0.5TiO3 abrupt interfaces had been optimized to become more compact, forming stable transition heterointerfaces. The SAB thin films exhibit excellent electric properties, including a breakdown strength of 580 MV m−1, an energy storage density of 16.4 J cm−3, and a leakage current density < 10–6 A cm−2 from 0 to 225 MV m−1. The finite element simulation was constructed to demonstrate the defect self-repair process under high electric field. This work offers a promising strategy to fabricate multilayer dielectric thin films with high breakdown strength and energy storage density. [ABSTRACT FROM AUTHOR]

Multifunctional ionic plastic crystals (IPCs) are a class of unique materials that exhibit a wide range of advanced applications. In this work, we proposed a strategy for the design of multifunctional, superior ion‐conducting IPCs with bistability in both magnetic and electric properties, moreover, we successfully prepared and thoroughly characterized such an IPC, [PMPyr][Ni(mnt)2] (1; PMPyr+=N‐propyl‐N‐methylpyrrolidinium, and mnt2−=maleonitriledithiolate). Plastic crystal 1 exhibits superior ion conduction near room temperature, and its ion conductivity reaches the order of 10−2 S cm−1 at 373 K. Remarkably, the crystal‐to‐plastic crystal transformation results in 1 simultaneously exhibiting electrical bistability and magnetic transition. Our study paves the way for the development of new IPCs with desirable functional properties. [ABSTRACT FROM AUTHOR]

Wide-bandgap 2D materials for UV photodetectors have many advantages, such as flexibility and efficiency. For this reason, the quest for novel 2D semiconductor materials is the primary focus of ongoing research endeavors. In this study, the electronic and optical characteristics of Janus Al2M2ClBr (M = O, S) monolayers have been meticulously examined by density functional theory (DFT). It was confirmed that these monolayers exhibit structural robustness for indirect bandgap Al2O2ClBr or direct bandgap Al2S2ClBr. Moreover, they demonstrate a low effective mass for the photogenerated electrons and holes. The bandgap is notably modulated by strain engineering, whereas the impact of the electric field is minimal. Notably, strong light absorption within the 8 to 12 eV range has been confirmed, with absorption coefficients surpassing 105 cm−1 for Janus Al2M2ClBr (M = O, S) monolayers. The optical properties can be finely tuned by strain engineering, although the influence of an electric field on these properties is insignificant. Considering the combination of optical and electrical characteristics, Janus Al2M2ClBr (M = O, S) monolayers are promising for UV photodetector applications. As a result, this study provides invaluable theoretical insights into the development of UV photodetectors utilizing Janus monolayers and is poised to significantly enrich the expansion of Janus monolayer materials in the foreseeable future. [ABSTRACT FROM AUTHOR]

With burgeoning considerations over energy issues and carbon emissions, energy harvesting devices such as triboelectric nanogenerators (TENGs) are developed to provide renewable and sustainable power. Enhancing electric output and other properties of TENGs during operation is the focus of research. Herein, two species (Nb2S2C and Ta2S2C) of a new family of 2D materials, Transition Metal Carbo‐Chalcogenides (TMCCs), are first employed to develop TENGs with doping into Polydimethylsiloxane (PDMS). Compared with control samples, these two TMCC‐based TENGs exhibit higher electric properties owing to the enhanced permittivity of PDMS composite, and the best performance is achieved at a concentration of 3 wt. ‰ with open circuit voltage (Voc) of 112 V, short circuit current (Isc) of 8.6 µA and charge transfer (Qsc) of 175 nC for Nb2S2C based TENG, and Voc of 127 V, Isc of 9.6 µA, and Qsc of 230 nC for Ta2S2C based TENGs. These two TENGs show a maximum power density of 1360 and 911 mW m−2 respectively. Moreover, the tribology performance is also evaluated with the same materials, revealing that the Ta2S2C/PDMS composite as the electronegative material presented a lower coefficient of friction (COF) than the Nb2S2C/PDMS composite. Their applications for energy harvesting and self‐powered sensing are also demonstrated. [ABSTRACT FROM AUTHOR]

ABSTRACT LiMn2O4 spinel was prepared via a solid‐state process. Powder XRD results revealed the formation of a single cubic phase structure with the grain sizes of 0.13 μm. The cubic spinel LiMn2O4 crystallized in the three‐dimensional (3D) frameworks of the MnO4 and LiO4 tetrahedra units. The optical study presents a band gap around 2.57 eV. We studied the stability of lithium‐manganese oxides using electrical impedance over a temperature range of 323 to 453 K. The AC electrical conductivity is on the order of 10−3–10−2 Ω·cm−1, confirming the semiconductor character of the material and indicating its importance in optoelectronic and energy storage devices. The variation of the exponent s indicates its significance, demonstrating that the overlapping small polaron tunneling (NSPT) conduction model describes the two phases of this material. [ABSTRACT FROM AUTHOR]

The angiotensin-converting enzyme-2 (ACE2) is a transmembrane glycoprotein, consisting of two segments: a large carboxypeptidase catalytic domain and a small transmembrane collectrin-like segment. This protein plays an essential role in blood pressure regulation, transforming the peptides angiotensin-I and angiotensin-II (vasoconstrictors) into angiotensin-1-9 and angiotensin-1-7 (vasodilators). During the COVID-19 pandemic, ACE2 became best known as the receptor of the S-protein of SARS-CoV-2 coronavirus. The purpose of the following research is to reconstruct the 3D structure of the catalytic domain of the rabbit enzyme rACE2 using its primary amino acid sequence, and then to compare it with the human analog hACE2. For this purpose, we have calculated the electric properties and thermodynamic stability of the two protein globules employing computer programs for protein electrostatics. The analysis of the amino acid content and sequence demonstrates an 85% identity between the two polypeptide chains. The 3D alignment of the catalytic domains of the two enzymes shows coincidence of the α-helix segments, and a small difference in two unstructured segments of the chain. The electric charge of the catalytic domain of rACE2, determined by 70 positively chargeable amino acid residues, 114 negatively chargeable ones, and two positive charges of the Zn2+ atom in the active center exceeds that of hACE2 by one positively and four negatively chargeable groups; however, in 3D conformation, their isoelectric points pI 5.21 coincide. The surface electrostatic potential is similarly distributed on the surface of the two catalytic globules, but it strongly depends on the pH of the extracellular medium: it is almost positive at pH 5.0 but strongly negative at pH 7.4. The pH dependence of the electrostatic component of the free energy discloses that the 3D structure of the two enzymes is maximally stable at pH 6.5. The high similarity in the 3D structure, as well as in the electrostatic and thermodynamic properties, suggests that rabbit can be successfully used as an animal model to study blood pressure regulation and coronavirus infection, and the results can be extrapolated to humans. [ABSTRACT FROM AUTHOR]

The structures and properties of the electric double layer (EDL) on zinc (Zn) anodes significantly influence the cycling and rate performance of aqueous Zn batteries (ZBs). Here, a strategy is reported to regulate the EDL structure through work function (Wf) engineering to effectively enhance the electrochemical performance of ZBs, which is enabled by electrolyte‐tailored growth of heterogenous metal with a large Wf on the Zn anode. The metal‐to‐metal charge transfer in heterostructured Zn metal induced by the disparity of Wf increases the surface charge density, which enriches the Zn ions and shortens the thickness of EDL. The compressed EDL weakens the repulsive force of Zn deposits to achieve a tightly stacked and dendrite‐free Zn deposition. Besides, the formed H2O‐deficient EDL structure enables the inorganic‐rich solid electrolyte interphase (SEI) with high Zn‐ion conductivity to inhibit the notorious parasitic reactions and improve the electrode reaction kinetics. Consequently, the Zn||Zn symmetric cells demonstrate an ultra‐long cycling life over 2700 cycles (the cumulative capacity reaches 5400 mA h cm−2) at a high current density of 50 mA cm−2. The Zn anodes show a high average Coulombic efficiency of 99.70% over 3650 cycles. The Zn||MnO2 full cells exhibit excellent practical‐level performance under cyclic continuous mode (3000‐cycle life at high rates) and cyclic intermittent mode (1170‐cycle life with 83.05% capacity retention). Practical pouch cells are also demonstrated with outstanding cycling performance. [ABSTRACT FROM AUTHOR]

Abrikosov vortices play a fundamental role in the magnetic and electric properties of superconductors. The study of their pinning forces is essential to better understand the stability of vortex lattices, with the aim of increasing critical currents in superconductors. However, the study of vortices is challenging because of their nanometric sizes and the large variation in the pinning forces. In this Letter, we use a single nitrogen-vacancy center in a nanodiamond as a nanoscale magneto sensor to locally probe single vortices and their pinning effects in a thin niobium film. This simple, far-field optical approach also offers the possibility of manipulating a single spin with a single flux quantum. [ABSTRACT FROM AUTHOR]

We report on the synthesis, crystal, and electronic structure, as well as the magnetic, and electric properties of the phosphorus‐containing tantalum nitride P1−xTa8+xN13 (x=0.1–0.15). A high‐pressure high‐temperature reaction (8 GPa, 1400 °C) of Ta3N5 and P3N5 with NH4F as a mineralizing agent yields the compound in the form of black, rod‐shaped crystals. Single‐crystal X‐ray structure elucidation (space group C2/m (no. 12), a=16.202(3), b=2.9155(4), c=11.089(2) Å, β=126.698(7)°, Z=2) shows a network of face‐ and edge‐sharing Ta‐centered polyhedra that contains small vacant channels and PN6 octahedra strands. Atomic resolution transmission electron microscopy reveals an unusual P/Ta disorder. Mixed‐valent tantalum atoms exhibit interatomic distances similar to those in metallic tantalum, however, the electrical resistivity is quite high in the order of 101 Ω cm. The density of states and the electron localization function indicate localized electrons in both covalent and ionic bonds between P/Ta and N atoms, combined with less localized electrons that do not contribute to interatomic bonds. [ABSTRACT FROM AUTHOR]

Core-shell structured fine grain dielectrics, featured with high dielectric constant and wide temperature stability, are essential for the production of high-end MLCCs. In this work, the core-shell structured 100BaTiO 3 - x BaO-2.4MgO-1.0ZrO 2 -0.03MoO 3 -2.25Y 2 O 3 -0.3MnO 2 -2.0SiO 2 (x = 0.5, 1.0, 1.5, 2.0, 3.0, 4.0) ceramics were prepared and the effects of BaO additions on the microstructure and dielectric properties were studied. The resulting ceramics exhibited fine grains (average size 280–300 nm) and demonstrated a high dielectric constant (>1780). Notably, the core-shell structure of the ceramics was affected by the BaO content, with the core volume gradually increasing as the BaO addition grew. This adjustment in composition was found to enhance the temperature stability and reliability of the materials. When the BaO addition reaches 4.0 mol%, the values of Δ C 150 / C 25 °C were effectively suppressed from −22 % to −10.3 % to meet the X8R specification, and the insulation resistivity increased by more than an order of magnitude, reaching a maximum of 11.6 × 1012 Ω m. Our findings highlight the potential of BaO as an effective additive for enhancing the dielectric properties of core-shell structured fine grain dielectrics for high-end MLCCs. [ABSTRACT FROM AUTHOR]

This study explores the influence of Co2+ and Cr3+ doping on the microstructure and electrical properties of Ba-hexagonal ferrite synthesized using the sol-gel method. X-ray diffraction (XRD) confirmed the formation of the anticipated hexagonal M-type crystal structure. Field emission scanning electron microscopy (FESEM) revealed the evolution of grain morphology with increasing doping levels, showcasing the formation of needle-like grains. Electrical characterization using an impedance analyzer investigated dielectric, impedance, electric modulus, and conductivity properties at room temperature. The analysis of the dielectric spectra indicated a decrease in dielectric constant and an increase in loss tangent with increasing dopant concentration. The electric modulus spectra provided evidence for non-Debye relaxation behavior, further supported by observations of relaxation processes at varying frequencies in the conductivity spectra. Additionally, an increase in doping led to a decrease in both relaxation time and AC conductivity. Electrochemical impedance spectroscopy (EIS) measurements yielded complex impedance curves. These curves exhibited good agreement with the values obtained through software-based simulations of grain and grain boundary characteristics. Furthermore, the distribution of grains and grain boundaries observed in FESEM micrographs aligned with the patterns predicted by the EIS software. [ABSTRACT FROM AUTHOR]

Quality inspection of electronic boards during the manufacturing process is a crucial step, especially in the case of specific and expensive power electronic modules. Soldering splash occurrence decreases the reliability and electric properties of final products. This paper aims to compare different YOLOv8 models (small, medium, and large) with the combination of basic image preprocessing techniques to achieve the best possible performance of the designed algorithm. As preprocessing methods, contrast-limited adaptive histogram equalization (CLAHE) and image color channel manipulation are used. The results show that a suitable combination of the YOLOv8 model and preprocessing methods leads to an increase in the recall parameter. In our inspection task, recall can be considered the most important metric. The results are supported by a standard two-way ANOVA test. [ABSTRACT FROM AUTHOR]

Cesium-tin-bromide perovskite (CsSnBr3) has focused on as a candidate material for all-inorganic perovskite solar cell and thermoelectric energy converter because of its optical, electrical, and thermal properties. On the other hand, the electrical properties have not been clarified yet because of several inconsistent reports. In this paper, we produced CsSnBr3 bulk from a melt using the precursor powder prepared by a mechanochemical process. From powder X-ray diffraction analysis, main phase of the precursor was CsSnBr3 perovskite, and minor impurities were Cs2SnBr4 and CsSn2Br5. Although main phase of the bulk produced from a melt was CsSnBr3, small amount impurity, CsSn2Br5 was confirmed. From the electrical conductivity (σt) measurement, irreversible temperature dependence of σt was observed at first time increasing temperature. The conductivity measured from room temperature to 443 K at the first time showed metallic behavior. On the other hand, the temperature dependence is changed into opposite with decreasing temperature. At this operation, σt decrease with decreasing temperature. This semiconductor like behavior was found to be reversible after first increasing temperature operation. These results indicate that post anneal as well as production process of CsSnBr3 would be important to control its electric property. [ABSTRACT FROM AUTHOR]

The Highly transparent and conducting aluminum doped zinc oxide thin films deposited on glass substrate held at 450°C using spray pyrolysis method. The structural analysis by X-rays diffraction showed that the films are of structure wurtzite with a preferential orientation according to the direction (002) for oxide zinc ZnO undoped, on the other that ZnO: Al has a direction (101). The crystallite size was varied from 34 to 36 nm with dopant concentration. The scanning electron microscopy results depicted that the microstructure of ZnO: Al films highly influenced by the aluminum doping. The measures optical showed that ZnO: Al layers have a transmission of about 85% and energy gap of 3.2 eV, 3.4 eV for ZnO:Al and ZnO respectively. The resistivity of the films decreased as increase the dopant concentration and it is 3 × 10−2 Ω cm for 1 at.% Al beyond which it increased. [ABSTRACT FROM AUTHOR]

Bilayer thin films of GdFeO3/Fe97Si3 have been synthesized by RF–magnetron sputtering at different thicknesses of GdFeO3. A pure phase polycrystalline growth of GdFeO3 and Fe97Si3 has been confirmed by XRD measurements. Stress-induced room-temperature magnetocrystalline anisotropy has been confirmed in all the bilayer thin films. A high magnetic moment has been induced in antiferromagnetic GdFeO3 thin films resulting in the ferromagnetic character of all the samples. The ferromagnetic moment was found to be enhanced with increasing thickness of the GdFeO3 layer. The maximum value of the room- temperature magnetic moment has been observed as Ms ~ 9.3 emu/ml in 170-nm-thick GdFeO3 film. Dielectric measurements confirmed the induced magnetocapacitance due to grain boundary accumulation of charge carriers. Magnetic field control of capacitance and current–voltage measurements of these thin films represents a strong potential for the existence of magnetoelectric coupling in GdFeO3/Fe97Si3 films. A maximum 30% rise in magnetocapacitance and a 95.6% increase in tunneling current in an applied 1-kOe magnetic field was obtained for 170-nm-thick GFO thin film. These thin films possess applications in spintronic devices due to the presence of room- temperature magnetocrystalline anisotropy and magnetic control of the electric properties. [ABSTRACT FROM AUTHOR]

Room‐temperature (RT) multiferroic materials have received significant research attention for various potential applications; however, their properties are not suitable for real‐world implementation. In this study, a nano‐scale localized flexoelectric effect is introduced to enhance the RT multiferroic performance of epitaxial bismuth iron oxide (BiFeO3; BFO) thin films by embedding 10 mol% Ba(Cu1/3Nb2/3)O3 (BCN) nano‐clusters into the host BFO film, which originally has a rhombohedral crystal structure. By utilizing nano‐clustering, a large out‐of‐plane coherent strain is localized around the nano‐clusters, resulting in a highly strained tetragonality of the BFO structure; subsequently, the films exhibit peculiar types of domains and domain walls, such as nano‐scale rotational vortices and antiparallel dipole configurations. These peculiar domain structures, which originate from the localized flexoelectric effect at the nano‐scale, enable excellent ferroelectric, ferromagnetic, and RT multiferroic magnetoelectric coupling. This study reveals that the local variation in the localized flexoelectric field around nano‐clusters considerably impacts the formation of unusual domain‐wall structures. This suggests that the controlled introduction of nano‐clusters with different crystal structures is promising for achieving the desired multiferroic properties. [ABSTRACT FROM AUTHOR]

The discovery of polar metal opens the door to incorporating electric polarization into electronics with the potential to invigorate next‐generation multifunctional electronic devices. Especially, electric polarization can be induced by geometric design in non‐polar perovskite oxides. Here, the epitaxial strain exerted on the deposited single‐crystalline NdNiO3 thin films is systematically varied in both sign and amplitude by choosing substrates with different lattice mismatch. The pseudocubic NdNiO3(111) film, which is non‐polar in its bulk state, is induced to be polar under both compressive and tensile strain. The fine‐tuning of epitaxial strain is realized by continuously varying the film thickness using the "thickness‐wedge" growth technique, and from the elucidated thickness dependence, the electric polarization and metallicity can be further optimized. Moreover, transitioning from isotropic to anisotropic epitaxial strain gives rise to an ideal polar metal state in the pseudocubic NdNiO3(102) film on an orthorhombic substrate, achieving a remarkably low resistivity of 173 µΩ cm at room temperature. The metal–insulator transition in NdNiO3 is completely suppressed and the polar metal state becomes the ground state at all temperatures. These results demonstrate alluring possibilities of induction and manipulation of both electric polarization and electric transport properties in functional perovskite oxides by epitaxial strain engineering. [ABSTRACT FROM AUTHOR]

Porphyrin complexes are of great importance due to their possible applications as sensors, solar cells and photocatalysts, as well as their ability to bind additional ligands. A valuable source of knowledge on their nature is their electric properties, which can be evaluated employing density functional theory (DFT) methods, supporting the experimental research. The present work aims at the application of small property-oriented basis sets in calculation of electric properties in transition metals, their oxides and test coordination complexes. Firstly, the existing polarized ZPol basis set for the first-row transition metals is modified in order to improve atomic polarizability results. For this purpose, optimization of the f-type polarization function exponent is carried out with respect to the value of average atomic polarizability of investigated metals. Next, both the original and the modified basis sets are employed in finite field CCSD(T) calculation of transition metal oxides' dipole moments, as well as DFT calculation of polarizabilities in porphyrin–zinc and porphyrin–zinc–thiazole complexes. The obtained results show that the ZPol and ZPol-A basis sets can be successfully employed in the calculation of linear electric properties in large systems. The optimization procedure used in the present work can be employed for other source basis sets and elements, leading to new efficient polarized basis sets. [ABSTRACT FROM AUTHOR]

Multiferroic materials have been intensively pursued to achieve the mutual control of electric and magnetic properties. The breakthrough progress in 2D magnets and ferroelectrics encourages the exploration of low-dimensional multiferroics, which holds the promise of understanding inscrutable magnetoelectric coupling and inventing advanced spintronic devices. However, confirming ferroelectricity with optical techniques is challenging in 2D materials, particularly in conjunction with antiferromagnetic orders in single- and few-layer multiferroics. Here, we report the discovery of 2D vdW multiferroic with out-of-plane ferroelectric polarization in trilayer NiI2 device, as revealed by scanning reflective magnetic circular dichroism microscopy and ferroelectric hysteresis loops. The evolution between ferroelectric and antiferroelectric phases has been unambiguously observed. Moreover, the magnetoelectric interaction is directly probed by magnetic control of the multiferroic domain switching. This work opens up opportunities for exploring multiferroic orders and multiferroic physics at the limit of single or few atomic layers, and for creating advanced magnetoelectronic devices. The authors find the coexistence of ferroelectric and antiferroelectric states induced by chiral degeneracy in helical magnetic order in trilayer NiI2, along with the emergence of exotic magnetoelectric coupling. [ABSTRACT FROM AUTHOR]

In the present communication, structural and electrical properties of Y0.95Ca0.05MnO3 (YCMO) manganite thin films, having different thicknesses grown on (100) single crystalline Nb:SrTiO3 (SNTO) substrate using pulsed laser deposition (PLD) technique, have been investigated. Influence of 100 MeV O+7 energetic ion irradiation has been understood on the basis of structure–property correlations across the lattice of YCMO manganite. Influence of YCMO film thickness and ion fluence on the electrical properties have also been explored in the context of lattice strain, crystallite size (CS), crystallinity, defect state, local annealing effect and three dimensional disorder. YCMO/SNTO interface experiences the presence of tensile strain which is found to vary between +1.02 and +1.88% for 100 nm YCMO/SNTO thin film whereas it is found to decrease monotonically from +1.50 to +0.98% for 200 nm and +1.40 to +0.92% for 300 nm upon increase in ion fluence. For higher thicknesses of YCMO/SNTO films (i.e. 200 and 300 nm), CS (estimated using Scherrer's formula) is found to increase from 19.73 nm for pristine to 25.01 nm for higher influence irradiated 200 nm film and from 24.91 nm for pristine to 27.97 nm for higher influence irradiated 300 nm film which has been ascribed to the local annealing effect across the YCMO/SNTO thin film lattices. Variation in dielectric constant with frequency, YCMO layer thickness and ion fluence has been understood on the bases of lattice strain, defect state, CS, crystallite boundaries, dipolar relaxation and universal dielectric response (UDR) model. Nature of ac conductivity has been understood well in the context of Jonscher's power law fits where correlated barrier hopping (CBH) mechanism has been confirmed as a responsible process for charge conduction across the YCMO/SNTO interfaces. Maximum barrier height (Wm) has been derived using its relation with power exponent from Jonscher's power law fits to ac conductivity data and its values are found to vary nonmonotonically between 0.3218 and 0.4849 eV for 100 nm YCMO/SNTO film however it gets enhanced from 0.2382 to 0.3820 eV for 200 nm and from 0.1977 to 0.2203 eV for 300 nm YCMO/SNTO films upon increase in oxygen ion fluence. These variations have been ascribed to the dominant impact of high resistive insulating nature of core of the YCMO crystallites and three dimensional disorder across YCMO manganite lattice. Present report serves a complex simultaneous impact of YCMO layer thickness, ion fluence and related structural aspects on the electrical properties of YCMO/SNTO films where defect state can be regenerated through well established experimental tool of SHI irradiation in a controlled way. The electric properties of YCMO/SNTO thin films are of paramount importance in a variety of technological applications and are of fundamental importance for materials science research. [ABSTRACT FROM AUTHOR]

Summary: The plant cuticle is located at the interface of the plant with the environment, thus acting as a protective barrier against biotic and abiotic external stress factors, and regulating water loss. Additionally, it modulates mechanical stresses derived from internal tissues and also from the environment. Recent advances in the understanding of the hydric, mechanical, thermal, and, to a lower extent, optical and electric properties of the cuticle, as well as their phenomenological connections and relationships are reviewed. An equilibrium based on the interaction among the different biophysical properties is essential to ensure plant growth and development. The notable variability reported in cuticle geometry, surface topography, and microchemistry affects the analysis of some biophysical properties of the cuticle. This review aimed to provide an updated view of the plant cuticle, understood as a modification of the cell wall, in order to establish the state‐of‐the‐art biophysics of the plant cuticle, and to serve as an inspiration for future research in the field. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Computational Applied Mechanics is the property of University of Tehran and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Stochastic analysis of the absorbed power density (APD) on skin surface exposed to radiation of halfwave dipole at 10, 30 and 90 GHz and for different antenna‐body distances is presented. Skin tissue is modeled as a half‐space consisting of one layer (skin) or three layers (skin, fat and muscle) whose permittivities and conductivities are uncertain. Deterministic part is based on numerical solution of Pocklington equation via Galerkin Bubnov Indirect Boundary Element method (GB‐IBEM) and numerical integration of the corresponding field integrals. Uncertainty from tissue electric parameters is propagated to APD via non‐intrusive Stochastic Collocation method (SCM) in order to compute stochastic moments of APD. For 1‐layered model APD stochastic moments are computed with 3 deterministic simulations. On the other hand APD mean and variance for 3 layered model are successfully computed with 13 deterministic simulations while skewness and kurtosis require 85 deterministic simulations. The ratio of APD standard deviation and mean decreases with frequency thus indicating that the uncertainty in the tissue electric properties has smaller effect on APD uncertainty at higher frequencies. Finally, sensitivity analysis carried out for both 1‐layered and 3‐layered models indicates the same conclusions. At 10 GHz skin permittivity and conductivity are the two most important parameters. However, as frequency increases the impact of skin conductivity prevails. This indicates that in frequency range 10–90 GHz the APD uncertainty quantification and sensitivity analysis can be carried out by using only 2‐dimensional stochastic model. Key Points: The reported values for tissue permittivity and conductivity are scattered, thus introducing the uncertainty in the output absorbed power density (APD)Stochastic Collocation can assure the computation of APD stochastic moments with good accuracy at relatively low number of simulationsSensitivity analysis shows that the impact of the inner layers' permittivity and conductivity is negligible [ABSTRACT FROM AUTHOR]

It is of great practical significance to improve the sensitivity and enhance the stability of lead zirconate titanate (PZT) piezoelectric ceramics under hydrostatic pressure condition. In this work, the xPb(Sb1/2Nb1/2)O3-(1 - x)Pb(Zr0.52Ti0.48) (PSN-PZT, x = 0. 018, 0. 020, 0. 022, 0. 025, 0. 030) piezoelectric ceramics were prepared with conventional solid-state method. The influence of PSN on the phase, microscopic morphology, curie temperature, dielectric property, ferroelectric property, and piezoelectric properties of ceramics has investigated. The sensitivity of PSN-PZT and traditional high sensitivity piezoelectric ceramics was measured comparatively within the hydrostatic pressure of 5 - 30 MPa. The results show that the incorporation of PSN can improve the sensitivity and enhance the hydrostatic figure of merit (HFOM) of PZT piezoelectric ceramics significantly. When x = 0. 020, the PSN-PZT ceramics have the best electric properties, planar electromechanical coupling factor kp =0. 641, longitudinal piezoelectric strain constant d33 = 325 pC/ N, transverse piezoelectric voltage constant g31 =16. 642 mV·m·N-1, isostatic piezoelectric voltage constant gh (5 MPa) = 9. 91 mV·m-1 ·Pa-1, HFOM (5 MPa) =679 x 10-15 Pa-1. [ABSTRACT FROM AUTHOR]

Recent years, the polarization response of ferroelectrics has been entirely studied. However, it is found that the polarization may disappear gradually with the continually applied of electric field. In this paper, taking K0.48Na0.52NbO3(KNN) as an example, it was demonstrated that the residual polarization began to decrease when the electric field frequency increased to a certain extent using a phase-field methods. The results showed that the content of out-of-plane domains increased first and then decreased with the increase of applied electric field frequency, the maximum polarization disappeared at high frequencies, and the hysteresis loop became elliptical. In order to further study the abnormal changes of hysteresis loops of ferroelectrics under high electric field frequency, we analyzed the hysteresis loop and dielectric response of solid solution 0.1SrTiO3-0.9K0.48Na0.52NbO3. It was found that the doped hysteresis loop maintained its shape at higher frequency and the dielectric constant increased. This kind of doping has a higher field frequency adaptability, which has a key guiding role in improving the dielectric properties of ferroelectric thin films and expanding the frequency application range of ferroelectric nano memory. [ABSTRACT FROM AUTHOR]

The dispersion of shock is universal in various media, and in plasmas, standing whistler waves represent the dispersion of collisionless shocks. These standing whistler waves are usually observed upstream of low Mach number planetary bow shocks and interplanetary shocks. However, our understanding of the plasma behavior and electric field properties within these waves remains limited. Using conjoint THEMIS and Magnetospheric Multiscale (MMS) observations, we report the first observation of standing whistler wave upstream of a fast shock in Earth's magnetosheath resulting from the interaction between a solar wind tangential discontinuity and the bow shock. High‐resolution MMS measurements provide unprecedented insights into these waves, characterizing their circular polarization, near‐parallel propagation to the shock normal, and fixed phase relative to the shock ramp. The observed field and particle characteristics are discussed in detail. Key Points: An interplanetary tangential discontinuity interacted with Earth's bow shock, generating a fast shock in the magnetosheathFirst observation of standing whistler waves upstream of the fast shock in magnetosheathThe field and particle characteristics are discussed [ABSTRACT FROM AUTHOR]

It is widely recognized that the application of nanoparticles has the potential to improve the dielectric properties of transformer oil. Nevertheless, there is a scarcity of studies that have utilized pure nanofluids, and in practical applications, it is inevitable for transformer oil to become contaminated. Therefore, this study conducted tests to investigate how the shape and size of metal contaminants impact the dielectric performance of Fe3O4 nanofluids. The findings from the levitation voltage test indicate that as the size and diameter of the particle increase, the levitation voltage value measured also increases, and conversely. Moreover, a higher concentration of nanoparticles leads to a higher measured levitation voltage value. On the other hand, the breakdown voltage test results demonstrate that larger and sharper particles result in lower measured breakdown voltage values, and vice versa. The simulation outcomes regarding electric field distribution reveal that larger and sharper particles correspond to higher measured electric field values, while the opposite is true for smaller and less sharp particles. [ABSTRACT FROM AUTHOR]

Incorporating specific defects into complex oxides facilitates the exploration of exotic phenomena and novel functionalities based on the intricate coupling between the defects and lattice/charge. However, methods for maximizing the density of specific defects while enhancing the desired properties have been rarely explored. In this study, the effect of N+ ion bombardment‐driven specific defects on the properties of bismuth ferrite (BFO) thin films was investigated. Furthermore, atomic structure characterization and computational processing revealed the displacement and orientation of the Fe atoms, which are linearly related to the degree of polarization. The ion bombardment introduced deep‐level trap states within the lattice, leading to a significant reduction in the leakage current and improved insulation performance of the films. By precisely engineering the defect content through N+ ion bombardment, the pure BFO thin films with remarkable and stable ferroelectric properties (remnant polarization, Pr = ∼116.8 µC·cm−2; leakage current, J = ∼1.5 × 10−8 A·cm−2) were fabricated. This innovative defect engineering‐based approach enables the customization and optimization of local ferroelectric order parameters, thereby establishing a solid foundation for designing functionalities across various functional material systems. [ABSTRACT FROM AUTHOR]

The manufacturing and characterization of nanographite films on substrates form the foundation for advances in materials science. Conductive graphite films are challenging products, as isolating graphite oxide is often necessary. In this study, nanographite suspensions containing non-oxidized graphite flakes were used to fabricate novel thin and ultrathin films via blade coating on industry-standard substrates. Films as thin as 346 nm were successfully fabricated. Moreover, it was possible to induce the orientation of the graphite nanoflakes via blade coating. This orientation led to electrical anisotropy; thus, the electrical behavior of the films in each orthogonal direction differed. After adjusting the coating parameters and the concentration of the nanographite flakes, the electrical conductivity ranged from 0.04 S/cm to 0.33 S/cm. In addition, with such adjustments, the transparency of the films in the visible range varied from 20% to 75%. By establishing a methodology for the tuning of both electrical and optical properties via adjustments in the nanographite suspension and coating parameters, we can fabricate resistant, conductive, and transparent films satisfying certain requirements. The results presented here can be extrapolated to enhance applications, especially for photonics and solar cells, in fields that require electrical conductive materials with high levels of transparency.

AbstractPolymer-based composites are highly regarded as favorable candidate materials for dielectrics in high-energy-density capacitors, owing to their exceptional flexibility and fast charge-discharge capabilities. Recently, multilayer-structured polymer composites have gained significant attention as a promising solution for energy storage and dielectric applications, offering a combination of high energy density and low dielectric loss. These polymer multilayer films, comprising two or more layers synthesized through specific fabrication processes, have presented extensive uses in various applications, including packaging and optical materials, such as oxygen barrier, holographic anti-counterfeiting, and optical sensing, due to their versatile and tunable functionalities. The distinctive chemical composition and structural design of these layers, whether symmetrically or gradient distributed, endow these dielectric composites with superior integrated electric properties. This review provides a comprehensive overview of fabrication methods and strategies employed in the latest advancements in dielectric multilayer-structured polymers for energy storage applications. It delves into the design and manufacturing techniques of advanced multilayer composites, highlighting the diverse strategies utilized to enhance energy performance, such as polarization manipulation, electric field distribution control, interfacial modification, and geometric confinement of interfaces within both organic and organic/inorganic multilayer-structured composites. Lastly, this review addresses the current challenges and future prospects in the development of multilayer composites with enhanced energy storage performance. [ABSTRACT FROM AUTHOR]

The paper presents the results of many years of research carried out in various organizations of the USSR and Russia in the process of developing thrusters with anode layer (TALs) and stationary plasma thrusters (SPTs). They are known under the general name "thrusters with closed electron drift" (TCEDs), since they are developed on the basis of plasma ion accelerators with closed electron drift (ACEDs). TCEDs have come a long way in development. As a result, the SPT has become one of the most widely used electric rocket thrusters (ERTs) and continues to develop. The TAL development has also reached a fairly high level and is close to practical use. Therefore, here we consider the main physical principles and research results that determined the progress in the SPT and TAL development with the aim of their analysis and generalization, as well as assessment of their applicability for further development such thrusters. A brief overview of the main stages of the SPT and TAL development and the results achieved at these stages are given. It is shown that the main problem of their further development is to ensure both high thrust efficiency and a long service life. It is also shown that the main factor limiting the service life of TALs and SPTs is the ingress of accelerated ions onto their structure elements; therefore, in order to control the ion motion, it is first of all necessary to understand the patterns of electric field formation in TCED discharges. New properties of TCED discharges and the peculiarities of electric field formation are revealed and their known properties are clarified, which determine the thickness and position of the acceleration zone with the main potential drop in the discharge and the flows of accelerated ions onto the thruster structure elements. The methods of controlling the thickness and position of the acceleration zone in an TCED by varying the magnetic field characteristics, successfully tested at the second stage of the SPT and TAL development, are considered and analyzed. It is shown that these methods make it possible to effectively control the operation of an TCED and its characteristics, and physical conditions ensuring the efficiency of their application are determined. Physical conditions for the implementation and justification of the feasibility of completely removing the acceleration zone from the thruster as the main direction of modern TCED development are determined, taking into account the analysis of the properties of the discharge and the peculiarities of electric field formation in an TCED. The main conclusions on the issues considered are given. [ABSTRACT FROM AUTHOR]

The variation of structural and electric properties is investigated via different characterization methods for NaNbO3 ceramics modified with Ta5+ ions. At room temperature, substitution of Ta5+ ions can effectively induce the phase coexistence and transition between orthorhombic antiferroelectric P and orthorhombic ferroelectric Q phase in NaNb1‐xTaxO3 ceramics. Thus, the ferroelectric and piezoelectric properties could be regulated with the maximum value of d33 (~37.3) at x = 0.05. Besides, with increasing temperature, multiple phase transitions are demonstrated through dielectric, XRD, and in situ Raman results. Moreover, the temperature of various phase transitions gradually shifts toward lower temperature with increasing Ta5+ ions. Correspondingly, the modulation mechanism is also discussed based on the evolution of Raman vibration. This work is instructive for regulatable applications of NaNbO3‐based materials. [ABSTRACT FROM AUTHOR]

Research on new-generation materials to meet the energy needs has begun to attract attention. Recetly, energy storage in materials has become the most researched area. As a result of the reaction of the MAX phase 312 Ti3SiC2 powder with hydrofluoric acid, a new 2D nanosized layered powder called MXene, similar to graphene, was obtained. MXenes, which have been studied in various sectors, especially energy, have attracted the attention of researchers owing to their multilayered structures. When Ti3SiC2 powder was treated with hydrofluoric acid (HF), an accordion-like two-dimensional Ti3C2Tx MXene structure was formed. In MXenes, surface coatings such as -O,-OH, and -F groups, which determine and affect various aspects of 2D materials, such as conductivity, constitute the application area. In this study, Ti3C2(OH)2-O and/or-OH surface terminations were examined using density functional theory (DFT) with the effect of the hydrofluoric acid etching time. Quantum Espresso program was used for DFT calculation. X-ray diffraction (XRD) and scanning electron microscopy (SEM and FESEM) were used to examine the MXenephase Ti3C2Tx powder and first-principles calculations were performed. The structural and electronic properties of MAX and MXene compounds were determined. The spin-orbit effect (SOI) was examined in the electronic structure of MXene. The total and partial densities of states (DOS) with and without spin orbit were calculated. [ABSTRACT FROM AUTHOR]

Electrodes can be recognized as the bridges between photodetectors (PDs) and outer measurement circuits. The interfacial electric properties between electrodes and sensitive materials would dominate the separation and collection of photo-induced charge carrier, which are recognized as one of the critical factors influencing the photo-detecting performance. In this paper, the electrode materials used in UV PDs are summarized and categorized according to their components. Then, the effects of electrode configurations (such as the contact types, band structure, and electrode structure) on the photoelectric performances of UV PDs are discussed. Varied kinds of specific electrodes such as transparent electrodes, flexible electrodes, and bio-originated electrodes are described. Finally, the perspective of electrodes in UV PDs is presented, which provides guidance for their future development. [ABSTRACT FROM AUTHOR]

Versatile properties of electric double layer supercapacitors such as high output power, safety, high efficiency and durability have gained so much attention for use as energy storage systems. On the other hand their applications have been limited due to an attributed low energy density. It therefore necessary to improve their quantum capacitance in an effective way. In this research, we have investigated the effects of monovacancy and divacancy, nonmetal doping and adsorption of transition metals (Co, Cu, Ni and Zn) on the quantum capacitance of monolayer SiC using first principles calculations. The calculated results show that, incorporating boron in defected 2D-SiC significantly improves the CQ of monolayer silicene. The corresponding CQ values for 1st, 2nd, 3rd and 4th boron substitutions are 59.4, 82.3, 110.2 and 79.4 µF/cm2 respectively, which were found to be good for anode materials for supercapacitors. Moreover, transitions metals adsorbed monolayer SiC were also found to significantly improve the CQ value with high output of 139.3 µF/cm2. Finally, embedding of these TMs (Co, Cu, Ni and Zn) in 2D SiC will provide better alternative to the use of toxic TMs embedded systems such Ti, Mo, Ba and so on. [ABSTRACT FROM AUTHOR]

The current transition to the electric car by all users is advancing steadily, and hence the design of these products occupies a prominent place in the car design sector. Likewise, the user experience is one of the determining aspects for the choice of a model. The main objective of this work is to determine, through eye tracking, which areas of an image (in this case, images of the front of cars) are more influential in the perception of the vehicle as either electric or combustion-powered, by segmenting the most important areas of a vehicle and users' perceptions thereof according to gender and other socio-demographic variables. This work provides an experimental design and a way to analyse and draw conclusions from an oculometry study for vehicles, as well as an initial design briefing for the generation of the visual identity of electric vehicles based on the perception of users for different elements of the vehicle. A methodology is proposed that includes the use of tools such as ANOVAs, eye-tracking, heat maps, tracking maps and fixation times. Through this data it is possible to develop optimal designs aligned with the user's perception. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)