jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Michele Conroy | Didrik R. Småbråten | Colin Ophus | Konstantin Shapovalov | Quentin M. Ramasse | Kasper A. Hunnestad | Sverre M. Selbach | Ulrich Aschauer | Kalani Moore | J. M. Gregg | U. Bangert | Massimiliano Stengel | Alexei Gruverman | Dennis Meier
Source: Advanced Materials (article, 2024-08-09)
Field: Materials Science — Materials Chemistry

Observation of Antiferroelectric Domain Walls in a Uniaxial Hyperferroelectric Ferroelectric domain walls are a rich source of emergent electronic properties and unusual polar order. Recent studies show that the configuration of ferroelectric walls can go well beyond the conventional Ising-type structure. Néel-, Bloch-, and vortex-like polar patterns have been observed, displaying strong similarities with the spin textures at magnetic domain walls. Here, the discovery of antiferroelectric domain walls in the uniaxial ferroelectric Pb<sub>5</sub>Ge<sub>3</sub>O<sub>11</sub> is reported. Highly mobile domain walls with an alternating displacement of Pb atoms are resolved, resulting in a cyclic 180° flip of dipole direction within the wall. Density functional theory calculations show that Pb<sub>5</sub>Ge<sub>3</sub>O<sub>11</sub> is hyperferroelectric, allowing the system to overcome the depolarization fields that usually suppress the antiparallel ordering of dipoles along the longitudinal direction. Interestingly, the antiferroelectric walls observed under the electron beam are energetically more costly than basic head-to-head or tail-to-tail walls. The results suggest a new type of excited domain-wall state, expanding previous studies on ferroelectric domain walls into the realm of antiferroic phenomena. Ferroelectricity ; Condensed matter physics ; Materials science ; Antiferroelectricity ; Dipole ; Domain wall (magnetism) ; Antiparallel (mathematics) ; Polar ; Domain (mathematical analysis) ; Piezoresponse force microscopy ; Excited state ; Dielectric ; Physics ; Magnetization ; Magnetic field ; Atomic physics Ferroelectric and Piezoelectric Materials ; Acoustic Wave Resonator Technologies ; Multiferroics and related materials
Authors: Mykyta R. Starovoit | Siddharth Jadeja | Taťána Gazárková | Juraj Lenčo
Source: Analytical Chemistry (article, 2024-08-28)
Field: Chemistry — Spectroscopy

Mitigating In-Column Artificial Modifications in High-Temperature LC–MS for Bottom–Up Proteomics and Quality Control of Protein Biopharmaceuticals Elevating the column temperature is an effective strategy for improving the chromatographic separation of peptides. However, high temperatures induce artificial modifications that compromise the quality of the peptide analysis. Here, we present a novel high-temperature LC-MS method that retains the benefits of a high column temperature while significantly reducing peptide modification and degradation during reversed-phase liquid chromatography. Our approach leverages a short inline trap column maintained at a near-ambient temperature installed upstream of a separation column. The retentivity and dimensions of the trap column were optimized to shorten the residence time of peptides in the heated separation column without compromising the separation performance. This easy-to-implement approach increased peak capacity by 1.4-fold within a 110 min peptide mapping of trastuzumab and provided 10% more peptide identifications in exploratory LC-MS proteomic analyses compared with analyses conducted at 30 °C while maintaining the extent of modifications close to the background level. In the peptide mapping of biopharmaceuticals, where in-column modifications can falsely elevate the levels of some critical quality attributes, the method reduced temperature-related artifacts by 66% for N-terminal pyroGlu and 63% for oxidized Met compared to direct injection at 60 °C, thus improving reliability in quality control of protein drugs. Our findings represent a promising advancement in LC-MS methodology, providing researchers and industry professionals with a valuable tool for improving the chromatographic separation of peptides while significantly reducing the unwanted modifications. Chemistry ; Chromatography ; Column (typography) ; Peptide ; Two-dimensional chromatography ; Trap (plumbing) ; Quality by Design ; Mass spectrometry ; Analytical Chemistry (journal) ; Computer science ; Particle size Mass Spectrometry Techniques and Applications ; Advanced Proteomics Techniques and Applications ; Analytical Chemistry and Chromatography
Authors: Marko D. Petrović | Manuel Weber | J. K. Freericks
Source: Physical Review X (article, 2024-09-25)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Theoretical Description of Pump-Probe Experiments in Charge-Density-Wave Materials out to Long Times We describe coupled nonequilibrium electron-phonon systems semiclassically—Ehrenfest dynamics for the phonons and quantum mechanics for the electrons—using a classical Monte Carlo approach that determines the nonequilibrium response to a large pump field. The semiclassical approach is expected to be accurate, because the phonons are excited to average energies much higher than the phonon frequency, eliminating the need for a quantum description. The numerical efficiency of this method allows us to perform a self-consistent time evolution out to very long times (tens of picoseconds), enabling us to model pump-probe experiments of a charge-density-wave (CDW) material. Our system is a half-filled, one-dimensional (1D) Holstein chain that exhibits CDW ordering due to a Peierls transition. The chain is subjected to a time-dependent electromagnetic pump field that excites it out of equilibrium, and then a second probe pulse is applied after a time delay. By evolving the system to long times, we capture the complete process of lattice excitation and subsequent relaxation to a new equilibrium, due to an exchange of energy between the electrons and the lattice, leading to lattice relaxation at finite temperatures. We employ an indirect (impulsive) driving mechanism of the lattice by the pump pulse due to the direct driving of the electrons. We identify two driving regimes, where the pump can either cause small perturbations or completely invert the initial CDW order. Our work successfully describes the ringing of the amplitude mode in CDW systems that has long been seen in experiment but never successfully explained by microscopic theory. We also describe the fluence-dependent crossover that inverts the CDW order parameter and changes the phonon dynamics. Finally, we illustrate how this method can examine a number of different types of experiments including photoemission, x-ray diffraction, and two-dimensional (2D) spectroscopy. Published by the American Physical Society 2024 Physics ; Excited state ; Phonon ; Non-equilibrium thermodynamics ; Electron ; Picosecond ; Charge density wave ; Excitation ; Condensed matter physics ; Lattice (music) ; Semiclassical physics ; Relaxation (psychology) ; Quantum ; Atomic physics ; Quantum mechanics Organic and Molecular Conductors Research ; Quantum and electron transport phenomena ; Physics of Superconductivity and Magnetism
Authors: Mohammad‐Taghi Golmakani | Ali Soltani | Shahriyar Sahraeian
Source: Grasas y Aceites (article, 2024-12-30)
Field: Chemistry — Organic Chemistry

Investigating the impact of palm oil refining on the oxidative stability of its blend with linseed oil: a kinetic approach This study investigates whether blending palm oil with linseed oil can enhance the oxidative stability of linseed oil, which is prone to oxidation due to its high polyunsaturated fatty acid content. Four blends were prepared: 66 % linseed oil with 33 % crude palm oil (33C), 33 % linseed oil with 66 % crude palm oil (66C), 66 % linseed oil with 33 % refined palm oil (33R), and 33% linseed oil with 66 % refined palm oil (66R). Oxidation kinetics were analyzed using peroxide value, p-anisidine value, TOTOX value, induction period, activation energy, and Gibbs free energy. The results showed that palm oil blends, particularly refined palm oil, significantly improved oxidative stability. The 66R sample exhibited the highest stability, with lower oxidation values, longer induction periods, and higher activation energy. Refining palm oil further enhanced its stabilizing effect. These findings offer practical solutions for the food industry to extend the shelf-life of linseed oil-based products, such as margarines and dressings, while maintaining their nutritional quality. Palm oil ; Linseed oil ; Refining (metallurgy) ; Oxidative phosphorylation ; Pulp and paper industry ; Chemistry ; Kinetic energy ; Environmental science ; Food science ; Engineering ; Biochemistry ; Physics Edible Oils Quality and Analysis ; Food Chemistry and Fat Analysis
Authors: Brunella Cafra | Alessandra Alberti | Gaetano Calogero | Ioannis Deretzis | Antonio Landi | Daniele Pagano | Salvatore Sanzaro | Antonino La Magna
Source: Crystals (article, 2024-01-26)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Mechanism of Grain Densification in Nano- and Poly-Crystalline Cu Films and Its Impact in Advanced Metallization Processes We investigate the microstructural evolution of electrochemically deposited poly-crystalline Cu films during subsequent thermal process cycles at mild maximum temperatures, compatible with the integration in advanced metallization schemes for electronic device manufacturing. The modifications induced by the thermal budget have been characterized at different scales (from the film-substrate interface to the wafer scale) with different complementary techniques: X-ray Diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), and dynamical warpage measurements. Moreover, the film internal grains’ evolution has been modelled by a tri-dimensional on-cell model, derived by the Pott-like multi-states configurational energy dependence, able to consider multiple orientation of the grains and densification kinetics in the canonical ensemble. Finally, a macroscopic model of the warpage dependence on the process conditions is discussed. The presented joint theoretical and experimental analysis provides a complete and consistent scenario of the grain densification phenomenon and its impact for the Cu film microstructure and the composite system morphology, indicating several strategies for the integration of the process in real device structures. Materials science ; Mechanism (biology) ; Nano- ; Nanotechnology ; Metallurgy ; Composite material Copper Interconnects and Reliability ; Electrodeposition and Electroless Coatings ; Semiconductor materials and devices
Authors: Morteza Sabeti | Farshid Torabi | Ali Cheperli
Source: The Canadian Journal of Chemical Engineering (article, 2024-10-09)
Field: Chemistry — Analytical Chemistry

Effects of pressure depletion rate, solvent, and surfactant on non‐equilibrium reactions in foamy oil Abstract This research employed a visual method to explore the behaviour of foamy oil in heavy oil systems. A Hele‐Shaw cell was designed for observing the volumetric expansion of foamy oil as the system pressure decreased. This approach facilitated an examination of foamy oil's interface evolution under pressure depletion and an analysis of bubble sizes and their distribution. Using Minitab, 15 experiments were strategized, aimed at observing the distribution of bubbles and their stability during the foamy oil process. The investigation also extended to studying the influence of surfactants, solvent type, and pressure reduction rate on foamy oil. The findings suggest that a high concentration of surfactant, a high percentage of CO 2 solvent, and a rapid pressure drop rate all contributed to the generation of microbubbles and enhanced volumetric expansion and stability of foamy oil. However, in light of the conducted energy analysis, a lower rate of pressure reduction is recommended. Finally, the conditions of the 15 experiments were applied to the CMG to derive two non‐equilibrium reactions for bubble generation and collapsing. The reaction rates are such that they relate bubble generation to the pressure reduction rate of the process and bubble resistance to collapsing to the surfactant concentration of the foamy oil. Pulmonary surfactant ; Chemistry ; Solvent ; Organic chemistry ; Biochemistry Petroleum Processing and Analysis ; Enhanced Oil Recovery Techniques ; Hydrocarbon exploration and reservoir analysis
Authors: Andreas Gottscholl | Hannes Kraus | Thomas Aichinger | Corey J. Cochrane
Source: Scientific Reports (article, 2024-06-20)
Field: Materials Science — Materials Chemistry

Enhancing the electrical readout of the spin-dependent recombination current in SiC JFETs for EDMR based magnetometry using a tandem (de-)modulation technique Electrically detected magnetic resonance (EDMR) is a promising method to readout spins in miniaturized devices utilized as quantum magnetometers. However, the sensitivity has remained challenging. In this study, we present a tandem (de-)modulation technique based on a combination of magnetic field and radio frequency modulation. By enabling higher demodulation frequencies to avoid 1/f-noise, enhancing self-calibration capabilities, and eliminating background signals by 3 orders of magnitude, this technique represents a significant advancement in the field of EDMR-based sensors. This novel approach paves the way for EDMR being the ideal candidate for ultra-sensitive magnetometry at ambient conditions without any optical components, which brings it one step closer to a chip-based quantum sensor for future applications. Magnetometer ; Demodulation ; Spins ; Optoelectronics ; Modulation (music) ; Physics ; Sensitivity (control systems) ; Magnetic field ; Materials science ; Computer science ; Electronic engineering ; Telecommunications Diamond and Carbon-based Materials Research ; Quantum and electron transport phenomena ; Atomic and Subatomic Physics Research
Authors: Yifu Cao | Chandan Setty | Andreas Kreisel | Laura Fanfarillo | P. J. Hirschfeld
Source: Physical review. B./Physical review. B (preprint, 2024-07-11)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Spin fluctuations in the ultranodal superconducting state of Fe(Se,S) An ultranodal superconducting state exhibits very unusual physical properties since it has a strongly enhanced low-energy density of states compared to a nodal state. The iron-based superconductor FeSe${}_{1\ensuremath{-}x}$S${}_{x}$ has been proposed as a realization of such an exotic state. The authors of this work examine here the consequences in this superconductor with Bogoliubov Fermi surfaces and find that the spin-relaxation rate shows an upturn towards low temperature as result of an interplay of correlation effects, multiband nature and the Bogoliubov Fermi surface. Condensed matter physics ; Superconductivity ; Spin (aerodynamics) ; State (computer science) ; Physics ; Mathematics ; Thermodynamics Iron-based superconductors research
Authors: René Heller
Source: Astronomy and Astrophysics (preprint, 2024-08-06)
Field: Chemistry — Organic Chemistry

Exocomet orbital distribution around <i>β</i> Pictoris The ~23 Myr young star β Pictoris ( β Pic) is a laboratory for planet formation studies because of its observed debris disk, its directly imaged super-Jovian planets β Pic b and c, and the evidence of extrasolar comets that regularly transit in front of the star. The most recent evidence of exocometary transits around β Pic came from stellar photometric time series obtained with the TESS space mission. Previous analyses of these transits constrained the orbital distribution of the underlying exocomet population to a range between about 0.03 and 1.3 AU assuming a fixed transit impact parameter. We examine the distribution of the observed transit durations (Δ t ) to infer the orbital surface density distribution ( δ ) of the underlying exocomet sample. The effect of the geometric transit probability for circular orbits was properly taken into account, but we assumed that the radius of the transiting comets and their possible clouds of evaporating material are much smaller than the stellar radius. We show that a narrow belt of exocomets around β Pic, in which the transit impact parameters are randomized but the orbital semimajor axes are equal, results in a pile-up of long transit durations. This is in contrast to observations, which reveal a pile-up of short transit durations (Δ t ≈ 0.1 d) and a tail of only a few transits with Δ t &gt; 0.4 d. A flat density distribution of exocomets between about 0.03 and 2.5 AU results in a better match between the resulting Δ t distribution and the observations, but the slope of the predicted Δ t histogram is not sufficiently steep. An even better match to the observations can be produced with a δ ∝ a β power law. Our modeling reveals a best fit between the observed and predicted Δ t distribution for β = −0.15 −0.10 +0.05 . A more reasonable scenario in which the exocometary trajectories are modeled as hyperbolic orbits can also reproduce the observed Δ t distribution to some extent. Future studies might reproduce the observed Δ t distribution with a full exploration of the four-dimensional parameter space of highly eccentric orbits, and they might need to relax our assumption that the transiting objects are smaller than the stellar disk. The number of observed exocometary transits around β Pic is currently too small to validate the previously reported distinction of two distinct exocomet families, but this might be possible with future TESS observations of this star. Our results nevertheless imply that cometary material exists on highly eccentric orbits with a more extended range of semimajor axes than suggested by previous spectroscopic observations. Distribution (mathematics) ; Physics ; BETA (programming language) ; Astronomy ; Astrophysics ; Mathematics ; Computer science ; Mathematical analysis Chemistry and Stereochemistry Studies
Authors: Khaled Alsamri | Sajjad Rezaei | Vanessa Chung | Jacqueline Huynh | Jack Brouwer
Source:  (article, 2024-01-04)
Field: Materials Science — Materials Chemistry

Dynamic modeling of Hydrogen SOFC/GT powered Aircraft with integration analysis This paper aims to advance the green transition of the aviation industry by introducing a dynamic modeling approach for the integration of Hydrogen solid oxide fuel cells (SOFCs) and gas turbines (GTs) in aircraft propulsion. Despite the significant potential for emission reduction and improved fuel efficiency, the adoption of the SOFC/GT system in aviation is impeded by a lack of research, particularly in dynamic modeling under diverse flight conditions. Through a comprehensive approach leveraging the STRIDES modeling program, the paper presents an analysis of the dynamic response and electrochemical characteristics of the system under varying power demands. The designed system achieves peak efficiency 71.4% and a power output of 1.29MW. The methodology also emphasizes the complexities of flight conditions and potential areas for system optimization and improvement. The study, with a focus on the rapid response of the SOFC/GT system of a representative Cessna S550 Citation S/II aircraft flight under dynamic conditions, paves the way for the broader adoption of this technology, contributing to global efforts in mitigating the environmental impact of aviation. Computer science ; Hydrogen ; Automotive engineering ; Aeronautics ; Aerospace engineering ; Engineering ; Chemistry Advancements in Solid Oxide Fuel Cells ; Catalytic Processes in Materials Science ; Rocket and propulsion systems research
Authors: Rafael Luque Merino | Dumitru Călugăru | Haoyu Hu | Jaime Díez-Mérida | A. Díez-Carlón | Takashi Taniguchi | Kenji Watanabe | Paul Seifert | B. Andrei Bernevig | Dmitri K. Efetov
Source: arXiv (Cornell University) (preprint, 2024-02-19)
Field: Materials Science — Materials Chemistry

Evidence of heavy fermion physics in the thermoelectric transport of magic angle twisted bilayer graphene It has been recently postulated, that the strongly correlated flat bands of magicangle twisted bilayer graphene (MATBG) can host coexisting heavy and light carriers. While transport and spectroscopic measurements have shown hints of this behavior, a more direct experimental proof is still lacking. Here, we explore the thermoelectric response of MATBG through the photo-thermoelectric (PTE) effect in gate-defined MATBG pn-junctions. At low temperatures, we observe sign-preserving, fillingdependent oscillations of the Seebeck coefficient at non-zero integer fillings of the moiré lattice, which suggest the preponderance of one carrier type despite tuning the Fermi level from hole to electron doping of the correlated insulator. Furthermore, at higher temperatures, the thermoelectric response provides distinct evidence of the strong electron correlations in the unordered, normal state. We show that our observations are naturally accounted for by the interplay of light and long-lived and heavy and short-lived electron bands near the Fermi level at non-zero integer fillings. Our observations firmly establish the electron and hole asymmetry of the correlated gaps in MATBG, and shows excellent qualitative agreement with the recently developed topological heavy fermion model (THF). Bilayer graphene ; Physics ; Condensed matter physics ; Magic angle ; Thermoelectric effect ; Graphene ; MAGIC (telescope) ; Fermion ; Engineering physics ; Quantum mechanics Graphene research and applications ; Advanced Physical and Chemical Molecular Interactions ; Quantum and electron transport phenomena
Authors: Najeeb Ullah | Mohammad Tariqul Islam | Ahasanul Hoque | Muhammad Amir Khalil | Haitham Alsaif | Mohamed S. Soliman | Md. Shabiul Islam
Source: Scientific Reports (article, 2024-10-22)
Field: Materials Science — Electronic, Optical and Magnetic Materials

High-efficient, polarization-insensitive, wide-angle, compact metamaterial energy harvester for S-band and C-band applications This article proposes a polarization-insensitive compact Metamaterial (MM) energy harvester that can be used seamlessly in the S-band and C-band frequencies. It is important to focus on the limitations of many current designs of harvesters, which need to be overcome. The existing devices are large and often operate in a single frequency band, while their Energy Harvesting (EH) efficiency is low. The proposed harvester solves these problems using smart technology, using a rectangle strip with two gaps, each containing 50 Ω resistors for efficient energy collecting. Also, four hexagonal ring resonators are embedded into the cross-dumbbell configuration, connecting them with strip lines. Smaller rectangular rings surround these hexagonal rings, each with gaps labelled g1-g4. Despite its sophisticated design, the size of this harvester is (10 × 10) mm<sup>2</sup> only. This harvester operates at frequencies of 3.5 GHz and 5.5 GHz, demonstrating remarkable absorption responses across varying polarizations and incident angles in both transverse electric (TE) and transverse magnetic (TM) modes. The simulation results indicated impressive energy harvesting efficiencies of 97% at 3.5 GHz and 98% at 5.5 GHz. In addition, experiments in an anechoic chamber with a 3 × 3 array (30 × 30) mm<sup>2</sup> were used to confirm the efficiencies empirically. The simulated and measured results showed a strong correlation, confirming the reliability of the proposed design. The proposed MM harvester is distinguished by its high efficiency, polarization-insensitive behaviour, and compactness, making it very promising for many applications in EH. Metamaterial ; Polarization (electrochemistry) ; Optoelectronics ; Multi band ; Computer science ; Physics ; Telecommunications ; Chemistry Metamaterials and Metasurfaces Applications ; Antenna Design and Analysis ; Energy Harvesting in Wireless Networks