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At least 361 records · Page 20

Development of scalable design optimization parameters for bi-component protective systems

Bi-component protection-systems need to withstand a variety of extreme loading conditions such as high-velocity projectile impact to shock and blast mitigation. The large number of parameters at each stage of bi-component protection system design process results in a near-infinite number of possible variables for optimization. The aim of this project is to identify the scaling laws linking material and geometric scales of the problem to the final impact performance, further including the effects of wave propagation/interaction and inter-component bonding. Specifically, the impact dynamics for different optimal projectile/target density ratios and relative component mass fractions are quantified for bonded ceramic/titanium alloy systems. The impact behavior such as wave mechanics and damage propagation within the target system is characterized and quantified via digital image correlation or via x-ray phase-contrast imaging.

36 MATERIALS SCIENCE↗

Josephson behavior in a metal-decorated topological-insulator Bi 0.91 Sb 0.09

We have fabricated W nanoscale clusters on a topological insulator Bi 0.91 Sb 0.09 . The W island arrays effectively induce two-dimensional superconductivity at the surface of Bi 0.91 Sb 0.09 via the superconducting proximity effect. We find that this heterostructure behaves as a dynamic Josephson junction, which shows a Fraunhofer-like pattern of the critical current versus the applied magnetic field. Microwave irradiation experiments reveal the existence of a 4π-periodic supercurrent carried by the topological surface state. Our results open up a route to induce topological superconductivity in a topological insulator.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Materials Data on Bi(BO2)3 by Materials Project

BiB3O6 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are two inequivalent B3+ sites. In the first B3+ site, B3+ is bonded to four O2- atoms to form BO4 tetrahedra that share corners with two equivalent BiO6 pentagonal pyramids. There is two shorter (1.45 Å) and two longer (1.51 Å) B–O bond length. In the second B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.35–1.41 Å. Bi3+ is bonded to six O2- atoms to form distorted BiO6 pentagonal pyramids that share corners with four equivalent BiO6 pentagonal pyramids and corners with two equivalent BO4 tetrahedra. There are a spread of Bi–O bond distances ranging from 2.16–2.61 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to one B3+ and two equivalent Bi3+ atoms. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two B3+ atoms. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two B3+ and one Bi3+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Bi(PdO2)2 by Materials Project

BiPd2O4 crystallizes in the tetragonal P4/nmm space group. The structure is two-dimensional and consists of one BiPd2O4 sheet oriented in the (0, 0, 1) direction. Pd3+ is bonded in a square co-planar geometry to four equivalent O2- atoms. All Pd–O bond lengths are 2.01 Å. Bi2+ is bonded in a 4-coordinate geometry to four equivalent O2- atoms. All Bi–O bond lengths are 2.25 Å. O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Pd3+ and one Bi2+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Bi(TeBr2)2 by Materials Project

BiTeBr4Te crystallizes in the triclinic P-1 space group. The structure is two-dimensional and consists of two tellurium molecules and one BiTeBr4 sheet oriented in the (0, 0, 1) direction. In the BiTeBr4 sheet, Bi2+ is bonded to six Br1- atoms to form edge-sharing BiBr6 octahedra. There are a spread of Bi–Br bond distances ranging from 2.71–3.14 Å. Te1+ is bonded in a distorted bent 120 degrees geometry to two Br1- atoms. There are one shorter (3.23 Å) and one longer (3.42 Å) Te–Br bond lengths. There are four inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 2-coordinate geometry to one Bi2+ and one Te1+ atom. In the second Br1- site, Br1- is bonded in a single-bond geometry to one Bi2+ atom. In the third Br1- site, Br1- is bonded in a distorted water-like geometry to two equivalent Bi2+ atoms. In the fourth Br1- site, Br1- is bonded in a 2-coordinate geometry to two equivalent Bi2+ and one Te1+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Bi(BO2)3 by Materials Project

BiB3O6 crystallizes in the orthorhombic Pca2_1 space group. The structure is three-dimensional. there are three inequivalent B3+ sites. In the first B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.45–1.55 Å. In the second B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.43–1.58 Å. In the third B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.46–1.50 Å. Bi3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Bi–O bond distances ranging from 2.32–2.76 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to three B3+ atoms. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two B3+ and one Bi3+ atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two B3+ and one Bi3+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to one B3+ and three equivalent Bi3+ atoms. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to two B3+ and one Bi3+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent B3+ and one Bi3+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Bi(BO2)3 by Materials Project

BiB3O6 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are three inequivalent B3+ sites. In the first B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.37 Å) and one longer (1.40 Å) B–O bond length. In the second B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.47–1.49 Å. In the third B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.47–1.50 Å. Bi3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Bi–O bond distances ranging from 2.26–2.95 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two B3+ and one Bi3+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two B3+ and one Bi3+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to two B3+ and two equivalent Bi3+ atoms. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to two B3+ and one Bi3+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to two B3+ and one Bi3+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to one B3+ and three equivalent Bi3+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Bi(BO2)3 by Materials Project

BiB3O6 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are three inequivalent B3+ sites. In the first B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.45–1.55 Å. In the second B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.46–1.54 Å. In the third B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.44–1.52 Å. Bi3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Bi–O bond distances ranging from 2.26–2.99 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to two B3+ and two equivalent Bi3+ atoms. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two B3+ and one Bi3+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one B3+ and three equivalent Bi3+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two B3+ and one Bi3+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two B3+ and one Bi3+ atom. In the sixth O2- site, O2- is bonded in a trigonal planar geometry to three B3+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Bi(Mo3S4)2 by Materials Project

BiMo6S8 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Mo+2.17+ is bonded to five S2- atoms to form a mixture of edge and corner-sharing MoS5 square pyramids. There are a spread of Mo–S bond distances ranging from 2.40–2.58 Å. Bi3+ is bonded in a body-centered cubic geometry to eight S2- atoms. There are two shorter (2.75 Å) and six longer (3.11 Å) Bi–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 4-coordinate geometry to three equivalent Mo+2.17+ and one Bi3+ atom. In the second S2- site, S2- is bonded in a 5-coordinate geometry to four equivalent Mo+2.17+ and one Bi3+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Bi(SbTe2)3 by Materials Project

BiSbTe3Sb2Te3 is MAX Phase-like structured and crystallizes in the trigonal R3m space group. The structure is two-dimensional and consists of three BiSbTe3 sheets oriented in the (0, 0, 1) direction and three Sb2Te3 sheets oriented in the (0, 0, 1) direction. In each BiSbTe3 sheet, Bi3+ is bonded to six Te2- atoms to form BiTe6 octahedra that share corners with three equivalent SbTe6 octahedra, edges with three equivalent SbTe6 octahedra, and edges with six equivalent BiTe6 octahedra. The corner-sharing octahedral tilt angles are 2°. There are three shorter (3.08 Å) and three longer (3.26 Å) Bi–Te bond lengths. Sb3+ is bonded to six Te2- atoms to form SbTe6 octahedra that share corners with three equivalent BiTe6 octahedra, edges with three equivalent BiTe6 octahedra, and edges with six equivalent SbTe6 octahedra. The corner-sharing octahedral tilt angles are 2°. There are three shorter (3.03 Å) and three longer (3.19 Å) Sb–Te bond lengths. There are three inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 6-coordinate geometry to three equivalent Sb3+ atoms. In the second Te2- site, Te2- is bonded in a 6-coordinate geometry to three equivalent Bi3+ atoms. In the third Te2- site, Te2- is bonded to three equivalent Bi3+ and three equivalent Sb3+ atoms to form edge-sharing TeBi3Sb3 octahedra. In each Sb2Te3 sheet, there are two inequivalent Sb3+ sites. In the first Sb3+ site, Sb3+ is bonded to six Te2- atoms to form a mixture of edge and corner-sharing SbTe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (3.04 Å) and three longer (3.21 Å) Sb–Te bond lengths. In the second Sb3+ site, Sb3+ is bonded to six Te2- atoms to form a mixture of edge and corner-sharing SbTe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (3.04 Å) and three longer (3.21 Å) Sb–Te bond lengths. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to six Sb3+ atoms to form edge-sharing TeSb6 octahedra. In the second Te2- site, Te2- is bonded in a 6-coordinate geometry to three equivalent Sb3+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Bi(BO2)3 by Materials Project

BiB3O6 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are three inequivalent B3+ sites. In the first B3+ site, B3+ is bonded to four O2- atoms to form BO4 tetrahedra that share corners with two equivalent BiO6 pentagonal pyramids. There is two shorter (1.45 Å) and two longer (1.51 Å) B–O bond length. In the second B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.34–1.41 Å. In the third B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.35–1.41 Å. Bi3+ is bonded to six O2- atoms to form distorted BiO6 pentagonal pyramids that share corners with four equivalent BiO6 pentagonal pyramids and corners with two equivalent BO4 tetrahedra. There are a spread of Bi–O bond distances ranging from 2.17–2.62 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two B3+ atoms. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two B3+ atoms. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two B3+ and one Bi3+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two B3+ and one Bi3+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to one B3+ and two equivalent Bi3+ atoms. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to one B3+ and two equivalent Bi3+ atoms.

36 MATERIALS SCIENCE↗

Bi-fidelity modeling of uncertain and partially unknown systems using DeepONets

Recent advances in modeling large-scale, complex physical systems have shifted research focuses towards data-driven techniques. However, generating datasets by simulating complex systems can require significant computational resources. Similarly, acquiring experimental datasets can prove difficult. For these systems, often computationally inexpensive, but in general inaccurate models, known as the low-fidelity models, are available. Here in this paper, we propose a bi-fidelity modeling approach for complex physical systems, where we model the discrepancy between the true system's response and a low-fidelity response in the presence of a small training dataset from the true system's response using a deep operator network, a neural network architecture suitable for approximating nonlinear operators. We apply the approach to systems that have parametric uncertainty and are partially unknown. Three numerical examples are used to show the efficacy of the proposed approach to model uncertain and partially unknown physical systems.

MATHEMATICS AND COMPUTING↗

Stabilizing dynamic subsea power cables using Bi-stable nonlinear energy sinks

This study investigates vibration mitigation of dynamic subsea cables through passive bi-stable nonlinear energy sinks (B-NESs). These devices suppress vibration energy in a broadband way, and can be regarded as extensions of classical linear tuned mass dampers (TMDs) which are narrowband devices. Through the open-source MoorDyn library, we simulated the vibrations of a vertical subsea cable equipped with a set of B-NESs. Multi-objective optimization was performed to detect the B-NES parameters for optimal mitigation of the cable vibrations. Advanced signal processing verified the efficacy of the optimized B-NESs not only to rapidly absorb and locally dissipate vibration energy, but also to nonlinearly scatter vibration energy from low to high frequencies within the cable itself. This last feature is especially beneficial for vibration mitigation of the undersea cable, as at higher frequencies the cable vibrations exhibit drastically reduced amplitudes and are more effectively dissipated by inherent structural damping and hydrodynamic radiation damping. This contrasts with traditional TMDs which can mitigate vibration only at a single frequency. Furthermore, our robustness study confirms the B-NES's effectiveness under even varying environmental conditions. Overall, the B-NES's capacity for broadband vibration mitigation renders it a promising retrofit solution for improving the performance and operational safety of dynamic power cables in offshore wind farms and other marine applications.

17 WIND ENERGY↗

Monolithic 4-Terminal 1.2 kV/20 A 4H-SiC Bi-Directional Field Effect Transistor (BiDFET) with Integrated JBS Diodes

In this paper, we report successful fabrication of the first large area, monolithic, 1.2 kV 4H-SiC Bi-Directional FETs (BiDFETs) with integrated JBS diodes in a 6-inch commercial foundry for use in matrix converters. The fabricated BiDFETs support high voltage (>1.2 kV) in the first and third quadrants. They exhibit very low on-resistance of 50 mΩ in the on-state in both quadrants when the 20 V gate bias is applied to both gates, allowing conduction of 20 A with 1 V drop. Fully gate voltage controlled output characteristics are also confirmed in both quadrants.

4-Quadrant switch↗

Materials Data on Cs(BI)6 by Materials Project

Cs(BI)6 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. there are two inequivalent Cs sites. In the first Cs site, Cs is bonded in a 6-coordinate geometry to six I atoms. There are three shorter (4.03 Å) and three longer (4.06 Å) Cs–I bond lengths. In the second Cs site, Cs is bonded to twelve I atoms to form distorted edge-sharing CsI12 cuboctahedra. There are a spread of Cs–I bond distances ranging from 4.09–4.30 Å. There are four inequivalent B sites. In the first B site, B is bonded in a distorted single-bond geometry to five B and one I atom. There is two shorter (1.79 Å) and three longer (1.80 Å) B–B bond length. The B–I bond length is 2.19 Å. In the second B site, B is bonded in a distorted single-bond geometry to five B and one I atom. There is four shorter (1.79 Å) and one longer (1.80 Å) B–B bond length. The B–I bond length is 2.18 Å. In the third B site, B is bonded in a distorted single-bond geometry to five B and one I atom. Both B–B bond lengths are 1.80 Å. The B–I bond length is 2.18 Å. In the fourth B site, B is bonded in a distorted single-bond geometry to five B and one I atom. Both B–B bond lengths are 1.80 Å. The B–I bond length is 2.19 Å. There are four inequivalent I sites. In the first I site, I is bonded in a single-bond geometry to one Cs and one B atom. In the second I site, I is bonded in a distorted single-bond geometry to two Cs and one B atom. In the third I site, I is bonded in a distorted single-bond geometry to two equivalent Cs and one B atom. In the fourth I site, I is bonded in a distorted single-bond geometry to one Cs and one B atom.

36 MATERIALS SCIENCE↗

Nucleation and Antiphase Twin Control in Bi 2 Se 3 via Step‐Terminated Al 2 O 3 Substrates

The epitaxial synthesis of high-quality 2D layered materials is an essential driver of both fundamental physics studies and technological applications. Bi 2 Se 3 , a prototypical 2D layered topological insulator, is sensitive to defects imparted during the growth, either thermodynamically or due to the film-substrate interaction. Here, in this study, it is shown that step-terminated Al 2 O 3 substrates with a high miscut angle (3°) can effectively suppress a particular hard-to-mitigate defect, the antiphase twin. Systematic investigations across a range of growth temperatures and substrate miscut angles confirm that atomic step edges act as preferential nucleation sites, stabilizing a single twin domain. First-principles calculations suggest that there is a significant energy barrier for twin boundary formation at step edges, supporting the experimental observations. Detailed structural characterization indicates that this twin-selectivity is lost through the mechanism of the 2D layers overgrowing the step edges, leading to higher twin density as the thickness increases. These findings highlight the complex energy landscape unique to 2D materials that is driven by the interplay between substrate properties, nucleation dynamics, and defect formation, and overcoming and controlling these are critical to improve material quality for quantum and electronic applications.

36 MATERIALS SCIENCE↗

Evolution of Dissipative Regimes in Atomically Thin Bi 2 Sr 2 CaCu 2 O 8 + x Superconductor

Thermoelectric transport is widely used to study Abrikosov vortex dynamics in unconventional superconductors. However, only a few thermoelectric studies have been conducted near the dimensional crossover that occurs when the vortex-vortex interaction length scale becomes comparable to the sample size. Here, the effects of finite size on the dissipation mechanisms of the Nernst effect in the optimally doped Bi 2 Sr 2 CaCu 2 O 8 + x high-temperature superconductor are reported, down to the atomic length limit. To access this regime, a new generation of thermoelectric chips based on silicon nitride microprinted circuit boards is developed. These chips ensure optimized signals while preventing sample deterioration. The results demonstrate that lateral confinement at the nanoscale can effectively reduce vortex dissipation. Investigating vortex dissipation at the micro- and nano-scale is essential for creating stable, miniaturized superconducting circuits.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

High Strain Response and Dielectric Properties of Bi 1/2 (Na 0.78 K 0.22 ) 1/2 TiO 3 Ceramics Doped with (Fe 1/2 Nb 1/2 ) 4+

Environmentally friendly piezoceramics Bi 1/2 (Na 0.78 K 0.22 ) 1/2 Ti 1-x (Fe 1/2 Nb 1/2 ) x O 3 (BNKT-FN) with FeNb (FN) ratios 0, 0.01, 0.02, 0.03 and 0.04 were synthesized via conventional solid-state reaction (CSSR). X-ray diffraction (XRD) analysis revealed that the FN complexes were completely dissolved in BNKT perovskite and the structural transition occurred from ferroelectric to relaxor state. The average grain sizes for x = 0, 0.01, 0.02, 0.03 and 0.04 were found to be 0.34 μm, 0.35 μm, 0.38 μm, 0.32 μm and 0.39 μm, respectively. It is observed that the grain size increased with the addition of FN, except for x = 0.03. Here, the coercive field (E c ) and remnant polarization (P r ) of the system were decreased with increasing FN concentration and the highest E c of 21.1 kV/cm and P r of 29.2 μC/cm 2 were noted for the base pure sample. In addition, the increase of FN content steadily broadened the dielectric anomaly at maximum dielectric constant temperature (T m ) in the BNKT-FN system. Consequently, unipolar normalized strain (S max /E max ) was found to be enhanced monotonically achieving the highest value of around 654 pm/V (x = 0.02). These properties suggest that the investigated system could be a promising eco-friendly candidate for piezoelectric actuators and many other applications requiring high piezoelectric induced strain.

25 ENERGY STORAGE↗