jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Ananya Renuka Balakrishna | Richard D. James
Source: npj Computational Materials (preprint, 2022-01-13)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Design of soft magnetic materials Abstract We present a strategy for the design of ferromagnetic materials with exceptionally low magnetic hysteresis, quantified by coercivity. In this strategy, we use a micromagnetic algorithm that we have developed in previous research and which has been validated by its success in solving the “Permalloy Problem”—the well-known difficulty of predicting the composition 78.5% Ni of the lowest coercivity in the Fe–Ni system—and by the insight it provides into the “Coercivity Paradox” of W. F. Brown. Unexpectedly, the design strategy predicts that cubic materials with large saturation magnetization m s and large magnetocrystalline anisotropy constant κ 1 will have low coercivity on the order of that of Permalloy, as long as the magnetostriction constants λ 100 , λ 111 are tuned to special values. The explicit prediction for a cubic material with low coercivity is the dimensionless number $$({c}_{11}-{c}_{12}){\lambda }_{100}^{2}/(2{\kappa }_{1})=81$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mo>(</mml:mo> <mml:mrow> <mml:msub> <mml:mrow> <mml:mi>c</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>11</mml:mn> </mml:mrow> </mml:msub> <mml:mo>−</mml:mo> <mml:msub> <mml:mrow> <mml:mi>c</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>12</mml:mn> </mml:mrow> </mml:msub> </mml:mrow> <mml:mo>)</mml:mo> </mml:mrow> <mml:msubsup> <mml:mrow> <mml:mi>λ</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>100</mml:mn> </mml:mrow> <mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> </mml:msubsup> <mml:mo>/</mml:mo> <mml:mrow> <mml:mo>(</mml:mo> <mml:mrow> <mml:mn>2</mml:mn> <mml:msub> <mml:mrow> <mml:mi>κ</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>1</mml:mn> </mml:mrow> </mml:msub> </mml:mrow> <mml:mo>)</mml:mo> </mml:mrow> <mml:mo>=</mml:mo> <mml:mn>81</mml:mn> </mml:math> for 〈100〉 easy axes. The results would seem to have broad potential application, especially to magnetic materials of interest in energy research. Coercivity ; Permalloy ; Magnetocrystalline anisotropy ; Condensed matter physics ; Magnetostriction ; Materials science ; Dimensionless quantity ; Magnet ; Anisotropy ; Magnetic hysteresis ; Ferromagnetism ; Magnetization ; Saturation (graph theory) ; Magnetic anisotropy ; Physics ; Thermodynamics ; Mathematics ; Magnetic field ; Optics ; Combinatorics ; Quantum mechanics Magnetic Properties and Applications ; Magnetic properties of thin films ; Microstructure and Mechanical Properties of Steels
Authors: Sandra Patricia Molina | Andrea Mariela Andrade | Glenda Elizabet Habel Bruera | José Ángel Olinuck
Source: STUDIES IN SOCIAL SCIENCES REVIEW (article, 2022-05-03)
Field: Chemistry — Analytical Chemistry

Quantification of shedding of leaves in yerba mate and determination of associated hormonal levels In recent years, leaf shedding in the yerba mate crop has been a phenomenon of important economic incidence, the cause of which is still unknown but has been attributed to various factors. The objective of the present study was to establish a methodology to quantify leaves shedding in yerba mate and to determine whether the high leaf shedding is due to a biotic or abiotic effect. In both plantations, high shedding of leaves was significant only when the lowest values of heliophany and the highest values of relative humidity were recorded. Coincidentally, a high percentage of green leaf detachment was recorded with the characteristic symptomatology of the fungus Cylindrocladium sp. An accumulation of ABA, JA and SA hormones was detected in yerba mate plants with high shedding of leaves, which was associated with the attack of the necrotrophic fungus Cylindrocladium sp. With predisposing climatic conditions for the manifestation of Cylindrocladium, an early harvest would reduce the loss of green leaves. The differences found among plants Cylindrocladium attack could be due to a genetic condition. The JA pathway may be the most important line of defense activated by Cylindrocladium infection. A high accumulation of JA and ABA has been detected in plants with high leaf shedding that could suppress the SA signaling pathway responsible for SAR establishment. Biology ; Abiotic component ; Fungus ; Horticulture ; Botany ; Crop ; Hormone ; Agronomy ; Ecology Heavy Metals in Plants ; Bee Products Chemical Analysis ; Seed Germination and Physiology
Authors: D Burda | Alexandr Knápek
Source:  (article, 2022-01-01)
Field: Materials Science — Materials Chemistry

Metal-organic structures as additives in polyvinylidene fluoride This research aims to obtain a more in-depth understanding of the field emission properties of tungsten single-tip field emitters (STFEs) coated with a several tens of nanometer thin barrier of Al 2 O 3 . The introduction of an additional barrier into the metal-vacuum interface system of the emitter can be beneficial to improve its performance. The tungsten emitters were prepared using a two-step electrochemical drop-off etching technique. Thin oxide barrier coatings were prepared by using low-temperature atomic layer deposition (ALD), a chemical vapor deposition technique. Field emission was studied in an internally developed field emission microscope (FEM) working in UHV vacuum (< 110-7 Pa), and the experimental field emission data were analyzed by the so-called Murphy-Good plotsThe value of the local work function of the grown oxide layer were investigated using Ultra-violet photoelectron spectroscopy (UPS). Polyvinylidene fluoride ; Materials science ; Metal ; Fluoride ; Composite material ; Metallurgy ; Chemistry ; Inorganic chemistry ; Polymer Silicone and Siloxane Chemistry ; Nanotechnology research and applications ; Inorganic Fluorides and Related Compounds
Authors: Chunmiao Ma | Jie Tang | Lu Yu | Kehan Wen | Quan Gan
Source: Chemistry - A European Journal (article, 2022-04-28)
Field: Chemistry — Spectroscopy

Optimization of an Asymmetric Reaction Abstract Invited for the cover of this issue are Quan Gan and co‐workers at the Huazhong University of Science and Technology. The image depicts aromatic oligoamide sequences winding around a substrate with conformational control. Read the full text of the article at 10.1002/chem.202200834 . Chemistry ; Computer science Analytical Chemistry and Chromatography ; Innovative Microfluidic and Catalytic Techniques Innovation
Authors: Alessandro Quaranta | Benedikt Zöhrer | Johanna Revol-Cavalier | Kurt Benkestock | Laurence Balas | Camille Oger | Gregory S. Keyes | Åsa M. Wheelock | Thierry Durand | Jean‐Marie Galano | Christopher E. Ramsden | Mats Hámberg | Craig E. Wheelock
Source: ChemRxiv (preprint, 2022-03-09)
Field: Chemistry — Spectroscopy

Development of a chiral SFC-MS/MS and reversed-phase LC-MS/MS platform for the quantitative metabolic profiling of octadecanoid oxylipins Octadecanoids are broadly defined as oxylipins (i.e., lipid mediators) derived from 18-carbon fatty acids. In contrast to the well-studied eicosanoids, there is a lack of analytical methods for octadecanoids, hampering further investigations in the field. We developed an integrated workflow combining chiral separation by supercritical fluid chromatography (SFC) and reversed-phase liquid chromatography (LC) coupled to tandem-MS detection for quantification of a broad panel of octadecanoids. The platform included 70 custom-synthesized analytical and internal standards to extend the coverage of the octadecanoid synthetic pathways. A total of 103 octadecanoids could be separated by chiral SFC and complex enantioseparations could be performed in <13 minutes, while the achiral LC method separated 67 species in 13.5 minutes. The LC method provided a robust complementary approach with greater sensitivity relative to the SFC method. Both methods were validated in solvent and surrogate matrix in terms of linearity, lower limits of quantification (LLOQ), recovery, accuracy, precision, and matrix effects. Instrumental linearity was good for both methods (R2>0.995) and LLOQ ranged from 0.03-6.00 ng/mL for SFC and 0.01-1.25 ng/mL for LC. The average accuracy in solvent and surrogate matrix ranged from 89-109% in SFC and from 106-220% in LC, whereas coefficients of variation (CV) were <14% (at medium and high concentration) and 26% (at low concentration). Validation in surrogate matrix showed negligible matrix effects (<16% for all analytes) and average recoveries ranged from 71-83%. The combined methods provide a platform to investigate the biological activity of octadecanoids and expand our understanding of these little studied compounds. Chromatography ; Chemistry ; Analyte ; Matrix (chemical analysis) ; Supercritical fluid chromatography ; High-performance liquid chromatography Analytical Chemistry and Chromatography ; Mass Spectrometry Techniques and Applications ; Eicosanoids and Hypertension Pharmacology
Authors: Damien Tristant | Andrew Cupo | Ilya Vekhter | Vincent Meunier | W. A. Shelton
Source: Physical review. B./Physical review. B (article, 2022-05-17)
Field: Materials Science — Materials Chemistry

Electronic and vibrational properties of bulk <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>Cr</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mi>Ge</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mi>Te</mml:mi><mml:mn>6</mml:mn></mml:msub></mml:mrow></mml:math> from first-principles calculations We use density functional theory based ab initio calculations to investigate the structural, vibrational, magnetic, and electronic properties of the layered ferromagnet ${\mathrm{Cr}}_{2}{\mathrm{Ge}}_{2}{\mathrm{Te}}_{6}$ (CGT) that has attracted attention for potential spintronic applications. We optimize the structure for a fixed $c/a$ ratio. Our results are in excellent agreement with experimental data on structure, phonons, and electronic properties. The use of van der Waals interactions and relativistic spin-orbit coupling yields accurate lattice constants and interlayer distances. Simultaneously, the adopted theoretical methods lead to a rigorous description of the vibrational normal modes, as well as the valence bands, that are in excellent agreement with Raman spectroscopy and angle-resolved photoemission spectroscopy spectra, respectively. The magnetic moment is slightly overestimated, and the magnetic anisotropy has the correct sign but is greater in magnitude than that in experiment. We find that inclusion of the on-site Coulomb repulsion on $\mathrm{Cr}\text{\ensuremath{-}}3d$ orbitals worsens agreement with experiment, in contrast to previous studies. Our results provide a path toward ab initio analysis of magnetic heterostructures based on CGT. Ab initio ; Electronic structure ; Physics ; Valence (chemistry) ; van der Waals force ; Density functional theory ; Condensed matter physics ; Materials science ; Atomic physics ; Quantum mechanics ; Molecule 2D Materials and Applications ; Iron-based superconductors research ; Quantum Dots Synthesis And Properties
Authors: Eui Su Lee | Han‐Cheol Ryu
Source: Photonics (article, 2022-12-10)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Resonance Control of VO2 Thin-Film-Based THz Double-Split Rectangular Metamaterial According to Aspect Ratio The resonance characteristics of a double-split rectangular metamaterial based on a vanadium dioxide (VO2) thin film were controlled according to the aspect ratio of the rectangle in the terahertz (THz) frequency region. The VO2 thin film line was etched between the double-split rectangular gaps so that the resonance band could be switched by varying the characteristics of the VO2 thin film. When the VO2 thin film is in an insulator state, the rectangle is separated and resonates individually; thus, it resonates in the high-frequency band. When the VO2 thin film changes from an insulator to a conductor with a change in the temperature, the divided rectangles are electrically connected to operate as a single resonator, and the resonant frequency shifts to a low-frequency band. Varying the aspect ratio of the rectangle changes the resonant frequency and resonance strength of the double-split rectangular metamaterial. If the aspect ratio is increased by fixing the width of the unit cell of the metamaterial and adjusting the height, the resonant frequency is lowered in all situations, regardless of the state of the VO2 thin film and the polarization of the incident THz wave. The resonant frequency and resonance strength of the double-split rectangular metamaterial proposed in this paper could be controlled stably through a change in only the aspect ratio, not the overall unit cell size. The proposed double-split rectangular metamaterial based on an etched VO2 thin film is expected to be essential for THz tag, sensing, and wireless communication applications. Metamaterial ; Materials science ; Rectangle ; Optics ; Terahertz radiation ; Resonance (particle physics) ; Thin film ; Optoelectronics ; Aspect ratio (aeronautics) ; Resonator ; Split-ring resonator ; Insulator (electricity) ; Physics Metamaterials and Metasurfaces Applications ; Radio Wave Propagation Studies ; Advanced Antenna and Metasurface Technologies
Authors: Xinyue Ding | Quan Yu | Xinqiong Lu | Xiaohao Wang | Xinming Huo | Xiang Qian
Source: ChemRxiv (preprint, 2022-12-27)
Field: Chemistry — Spectroscopy

SWIFTSIN: A High-Resolution Ion Isolation Waveform for the Miniaturized Linear ion Trap Mass Spectrometer by Coarse to Fine Excitation To figure out the reason for the drawback of the SWIFT waveform and realize the high-resolution ion isolation on the miniaturized linear ion trap mass spectrometer, we studied the efficiency that ions can be excited under different excitation durations and amplitudes at different frequencies and compared the overlap ratios of the effective excitation frequency bandwidths of the adjacent ions. According to this, we proposed a new coarse-to-fine isolation waveform named SWIFTSIN. By superposing one or more sinusoidal waveforms on the SWIFT waveform and modulating the phases of the superposed sinusoidal waveforms, the generated SWIFTSIN waveform can achieve unit mass isolation on the miniaturized linear ion trap mass spectrometer without reducing the intensity of the target ion. The isolation ability of the SWIFTSIN waveform was verified by isolating a single isotope peak in the mixed samples. Waveform ; Ion trap ; Ion ; Quadrupole ion trap ; Amplitude ; Mass spectrometry ; Excitation ; Excited state ; Atomic physics ; Chemistry ; Analytical Chemistry (journal) ; Physics ; Optics ; Voltage Mass Spectrometry Techniques and Applications ; Analytical Chemistry and Sensors ; Isotope Analysis in Ecology
Authors: M. A. Bawa | Mohamad Wafirul Hadi | H. Dandakouta | Abuhuraira Aliyu
Source: Saudi Journal of Engineering and Technology (article, 2022-02-09)
Field: Materials Science — Materials Chemistry

Investigation of Excessive Wear of Ashaka Coal Mill Riser Duct and Idendifying the Optimum Solution Cement plants use fuel in burning limestone to make clinker in kilns. Due to high cost of fuels, most Cement plants are changing from high-cost liquid fuel like heavy fuel to cheap solid fuel like coal. Ashaka adopt the later. The coal is first pulverised in a ball mill and leaves the mill through a riser duct by pneumatic transport before been used in the kiln as fuel. The riser duct undergoes excessive wear which result in frequent downtime and affect the intendent purpose of fuel substitution. Also, the pulverised coal escaping under pressure through eroded areas on the duct increase the risk of fire and reduce the overall safety of the workshop. Current method which involved patching the duct by welding fail to solve the problem. This work investigates the root cause of the frequent wear of the riser duct by checking the abrasiveness of the coal being transported, checking the effect of the duct profile on wear through simulation using computational fluid dynamics (CFD). Checking the duct material rate of wear and providing the best solution in terms of cost and feasibility. After simulation using CFD it was revealed that the duct profile contributed to the wear rate. Since changing the profile will be costly, a different solution approach was considered i.e., surface finishing. Different Material samples suggested to be used as surface finishing on the duct were tested for wear at different angles using an abrasive test equipment. The test equipment which conforms with ASTM was designed, simulated using CFD and constructed. The best material with good wear resistance was found to be galvanised steel coated with automobile anti gravel and grounded with P1000. Coating the internal of the riser duct with the above material is considered to be the optimum solution in terms of cost and feasibility. Duct (anatomy) ; Coal ; Waste management ; Kiln ; Computational fluid dynamics ; Welding ; Engineering ; Mechanical engineering ; Environmental science ; Materials science ; Petroleum engineering Metal Alloys Wear and Properties ; Mechanical stress and fatigue analysis ; Tribology and Wear Analysis
Authors: Maria A. Toma | Guanglin Niu | Jennifer Geara | Ning Xu
Source: Journal of Investigative Dermatology (article, 2022-11-18)
Field: Materials Science — Biomaterials

596 Elucidating the role of Circular RNA circGLIS3 in human skin wound healing Wound healing ; Cell biology ; Fibroblast ; Human skin ; RNA ; Biology ; Small interfering RNA ; Gene expression ; Dermal fibroblast ; Molecular biology ; Gene ; Cell culture ; Immunology ; Genetics Silk-based biomaterials and applications ; Circular RNAs in diseases
Authors: Chengyi Xie | Yanyan Chen | Xiaoxiao Wang | Yuanyuan Song | Yuting Shen | Xin Diao | Lin Zhu | Jianing Wang | Zongwei Cai
Source: bioRxiv (Cold Spring Harbor Laboratory) (preprint, 2022-07-05)
Field: Chemistry — Spectroscopy

Chiral Derivatization-enabled Discrimination and Visualization of Proteinogenic Amino Acids by Ion Mobility Mass Spectrometry Abstract The importance of chiral amino acids (AAs) in living organisms has been widely recognized since the discovery of endogenous D-AAs as potential biomarkers in several metabolic disorders. Chiral analysis by ion mobility spectrometry-mass spectrometry (IMS-MS) has the advantages of high speed and sensitivity but is still in its infancy. Here, a N α -(2,4-dinitro-5-fluorophenyl)-L-alaninamide (FDAA) derivatization is combined with trapped ion mobility spectrometry-mass spectrometry (TIMS-MS) for chiral AA analysis. For the first time, we demonstrate the simultaneous separation of 19 pairs of chiral proteinogenic AAs in a single fixed condition TIMS-MS run. The utility of this approach presents for mouse brain extracts by direct-infusion TIMS-MS. The robust separation ability in complex biological sample was proven in MALDI TIMS mass spectrometry imaging (MSI) as well by directly depositing 19 pairs of AAs on a tissue slide following on-tissue derivatization. In addition, endogenous chiral amino acids were also detected and distinguished. The developed methods show compelling application prospects in biomarker discovery and biological research. Entry for the Table of Contents The combination of chiral derivatization and trapped ion mobility-mass spectrometry provides the first insights into the separation of 19 pairs of chiral proteinogenic D/L-amino acids in a single run and further visualization of chiral amino acids under complex biological matrix. Derivatization ; Mass spectrometry ; Chemistry ; Amino acid ; Ion-mobility spectrometry ; Chromatography ; Mass spectrometry imaging ; Ion-mobility spectrometry–mass spectrometry ; Tandem mass spectrometry ; Selected reaction monitoring ; Biochemistry Mass Spectrometry Techniques and Applications ; Amino Acid Enzymes and Metabolism ; Molecular Sensors and Ion Detection
Authors: Theodore V. Gortsas | D. G. Aggelis | D. Polyzos
Source: arXiv (Cornell University) (preprint, 2022-10-18)
Field: Materials Science — Materials Chemistry

The strain gradient elasticity via nonlocal considerations Strain gradient elasticity and nonlocal elasticity are two enhanced elastic theories intensively used over the last fifty years to explain static and dynamic phenomena that classical elasticity fails to do. The nonlocal elastic theory has a clear differentiation from the classical case by considering stresses in a point of the continuum as an integral of all stresses defined in the treated elastic body. On the other hand, strain gradient elasticity is characterized as a non-classical theory because considers both potential and kinetic energy densities as not only functions of strains and velocities, respectively but also functions of their gradients. Although the two considerations seem to be completely different from each other, it is a common belief that strain gradient elasticity has a lot in common with nonlocal elasticity. The goal of the present work is to derive all the strain gradient elastic theories appearing so far in the literature via nonlocal definitions of the potential and kinetic energy densities. Such a derivation demonstrates the common roots of the two theories and explains the nature of the involved intrinsic parameters in strain gradient elastic theories. For the sake of simplicity and brevity, only one-dimensional wave propagation phenomena are considered. Elasticity (physics) ; Elastic energy ; Classical mechanics ; Kinetic energy ; Physics ; Mathematics ; Mechanics ; Thermodynamics Nonlocal and gradient elasticity in micro/nano structures ; Thermoelastic and Magnetoelastic Phenomena ; Diamond and Carbon-based Materials Research
Authors: Sung‐Jae Joo | Jeongin Jang | Ji‐Hee Son | Bong-Seo Kim | Bok‐Ki Min
Source: Korean Journal of Metals and Materials (article, 2022-11-01)
Field: Materials Science — Materials Chemistry

Effects of V Alloying on Thermoelectric Properties of NbFeSb Half-Heusler Materials Codoped with Ti, Zr, and Sn NbFeSb-based alloys are promising &lt;i&gt;p&lt;/i&gt;-type half-Heusler materials with excellent thermoelectric performance, thermal stability, and naturally abundant constituent elements. Alloying and doping are powerful techniques for enhancing the thermoelectric properties of half-Heusler materials. This study experimentally investigated the effects of V alloying in NbFeSb codoped with Ti, Zr, and Sn. As the V content increases, the electrical conductivity of Nb&lt;sub&gt;0.8−x&lt;/sub&gt;V&lt;sub&gt;x&lt;/sub&gt;Ti&lt;sub&gt;0.15&lt;/sub&gt;Zr&lt;sub&gt;0.05&lt;/sub&gt;FeSb&lt;sub&gt;0.98&lt;/sub&gt;Sn&lt;sub&gt;0.02&lt;/sub&gt; (&lt;i&gt;x&lt;/i&gt; = 0, 0.05, 0.1, 0.2, and 0.3) decreases monotonically because of a simultaneous reduction in carrier concentration and mobility, reducing the power factor up to −39% from 4.13 (x = 0) to 2.52 mW m&lt;sup&gt;−1&lt;/sup&gt;K&lt;sup&gt;−2&lt;/sup&gt; (&lt;i&gt;x&lt;/i&gt; = 0.3) at 298 K. Moreover, the lattice thermal conductivity decreases with increasing &lt;i&gt;x&lt;/i&gt; by as much as −40% at the maximum V content of &lt;i&gt;x&lt;/i&gt; = 0.3, demonstrating that V addition considerably enhances phonon scattering even in the presence of substitutional dopants Ti, Zr, and Sn. The differences in the mass and size of V and Nb atoms cause a substantial decrease in lattice thermal conductivity. According to our study, the addition of a small V content to Hf-free NbFeSbbased alloys can improve their thermoelectric properties, and a maximum dimensionless figure of merit &lt;i&gt;zT&lt;/i&gt; of 0.89 was obtained in Nb&lt;sub&gt;0.75&lt;/sub&gt;V&lt;sub&gt;0.05&lt;/sub&gt;Ti&lt;sub&gt;0.15&lt;/sub&gt;Zr&lt;sub&gt;0.05&lt;/sub&gt;Sn&lt;sub&gt;0.98&lt;/sub&gt;Sb&lt;sub&gt;0.02&lt;/sub&gt; at 973 K. Materials science ; Thermoelectric effect ; Dopant ; Analytical Chemistry (journal) ; Doping ; Electrical resistivity and conductivity ; Thermoelectric materials ; Thermal conductivity ; Chemistry ; Physics Advanced Thermoelectric Materials and Devices ; Heusler alloys: electronic and magnetic properties ; Chalcogenide Semiconductor Thin Films