jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Samuel Aldana | Ion Alin Spiridon | Lulin Wang | Hongzhou Zhang
Source: arXiv (Cornell University) (preprint, 2024-01-03)
Field: Materials Science — Materials Chemistry

Understanding Substrate Effects on Two-Dimensional MoS2 Growth: a Kinetic Monte Carlo Approach Controlling the morphology of two-dimensional (2D) transition metal dichalcogenides (TMDs) plays a key role in their applications. Although chemical vapor deposition can achieve wafer-scale growth of 2D TMDs, a comprehensive theoretical framework for effective growth optimization is lacking. Atomistic modeling methods offer a promising approach to delve into the intricate dynamics underlying the growth. In this study, we employ kinetic Monte Carlo (kMC) simulations to identify crucial parameters that govern the morphology of MoS2 flakes grown on diverse substrates. Our simulations reveal that large adsorption rates significantly enhance growth speed, which however necessitates rapid edge migration to achieve compact triangles. Substrate etching can tune the adsorption-desorption process of adatoms and enable preferential growth within a specific substrate region, controlling the flake morphology. This study unravels the complex dynamics governing 2D TMD morphology, offering a theoretical framework for decision-making in the design and optimization of TMD synthesis processes. Kinetic Monte Carlo ; Substrate (aquarium) ; Materials science ; Wafer ; Nanotechnology ; Monte Carlo method ; Etching (microfabrication) ; Chemical physics ; Chemical vapor deposition ; Enhanced Data Rates for GSM Evolution ; Adsorption ; Desorption ; Chemistry ; Computer science ; Layer (electronics) ; Physical chemistry ; Geology ; Mathematics 2D Materials and Applications ; Graphene research and applications ; Advanced Sensor and Energy Harvesting Materials
Authors: G. Contopoulos | Athanasios C. Tzemos
Source: arXiv (Cornell University) (preprint, 2024-11-19)
Field: Chemistry — Spectroscopy

Classical and Bohmian trajectories in integrable and non integrable systems In the present paper we study the classical and the quantum Hénon-Heiles systems. In particular we make a comparison between the classical and the quantum trajectories of the integrable and of the non integrable Hénon Heiles Hamiltonian. From a classical standpoint, we study theoretically and numerically the form of the invariant curves in the Poincaré surfaces of section for several values of the coupling parameter of the integrable case and compare them with those of the non integrable case. Then we study the corresponding Bohmian trajectories and we find that they are chaotic in both cases, but chaos emerges at different times. Integrable system ; Mathematical physics ; Mathematics ; Physics ; Classical mechanics Molecular spectroscopy and chirality ; Quantum Mechanics and Applications
Authors: Jihyuk Park | Nam‐Su Huh | Kyoungsoo Park
Source: Journal of the Computational Structural Engineering Institute of Korea (article, 2024-08-31)
Field: Materials Science — Metals and Alloys

Numerical Modeling of Hydrogen Embrittlement-induced Ductile Fracture Using a Gurson-Cohesive Model (GCM) and Hydrogen Diffusion 37 4(2024.8)267 Hydrogen embrittlement ; Hydrogen ; Materials science ; GCM transcription factors ; Embrittlement ; Diffusion ; Fracture (geology) ; Metallurgy ; Composite material ; Thermodynamics ; Geology ; Chemistry ; Corrosion ; Physics Hydrogen embrittlement and corrosion behaviors in metals ; Nuclear Materials and Properties ; Corrosion Behavior and Inhibition
Authors: Maja Vončina | Tilen Balaško | Jožef Medved | Aleš Nagode
Source: Journal of Mining and Metallurgy Section B Metallurgy (article, 2024-01-01)
Field: Materials Science — Materials Chemistry

Influence of tool steel alloying elements Mo and Ni on the formation of the interaction layer between tool steels and molten aluminium alloys The alloying elements present in both tool steel and aluminium are influenced in the dissolution of tool steels in molten aluminum alloys. This study aims to predict how the alloying elements in the tool steel, particularly nickel (Ni) and molybdenum (Mo), impact the formation of the interaction layer between the tool steel and the molten aluminium alloy. The interaction layer between the investigated tool steels Dievar or RavnexHD and the aluminium alloys Al99.9 and Al99.7 consists of an intermetallic and a composite layer. The interaction layer between the investigated tool steels and the AlSi12 aluminium alloy consists of three different interaction layers. The hot-work tool steel RavnexHD shows the better solubility resistance in various molten aluminium alloys. The main alloying element in the tool steels investigated that has an influence on the dissolution of tool steel in molten aluminium is Ni, which is present in higher amounts in RavnexHD. Ni incorporate in the matrix, and inhibits the diffusion of iron and aluminium through the matrix. Mo in Dievar tool steel forms carbides, allowing easier diffusion of these elements through the Fe-matrix. The resilience in molten aluminium alloys is demonstrated by Ravnex HD tool steel for hot work. Metallurgy ; Materials science ; Aluminium ; Layer (electronics) ; Composite material Metal Alloys Wear and Properties ; Material Properties and Applications ; Metallurgy and Material Forming
Authors: B. E Vintaykin | Tatyana I. Kopylova | А. Е. Смирнов | Н. А. Смирнова | Ya. V. Cherenkov
Source: Микология и фитопатология (article, 2024-08-15)
Field: Materials Science — General Materials Science

FAZOVOE SOSTOYaNIE POVERKhNOSTNYKh SLOEV STALI VKS-10 POSLE LAZERNOY OBRABOTKI I POSLEDUYuShchEGO AZOTIROVANIYa Методом рентгеновской дифрактометрии поликристаллических образцов с использованием математических методов для повышения разрешающей способности получены данные о фазовом составе и истинном уширении дифракционных максимумов стали ВКС-10 на основе Fe-Cr-Ni, подвергнутой лазерной обработке с разной интенсивностью и последующему азотированию. Также исследованы закономерности формирования нитридных фаз при рассмотренных видах обработки. Установлено, что с увеличением интенсивности лазерной обработки возрастает количество твердого раствора на основе y-Fe и оксидных фаз, а также увеличиваются ширины дифракционных линий. После азотирования появляются нитридные фазы CrN, Fe3N, Fe4N, их объемные доли значительно возрастают с увеличением интенсивности лазерной обработки, однако при двукратной лазерной обработке доля нитридных фаз снижается. Environmental science Material Properties and Applications ; Engineering and Environmental Studies ; Engineering Technology and Methodologies
Authors: Kadioğlu | Şakar
Source: Bulgarian Chemical Communications (article, 2024-09-18)
Field: Materials Science — Polymers and Plastics

Methyl violet dye removal investigation on submicron particle size rubber powder obtained from scrap tyre functionalized with agar-agar In this study, submicron particle size rubber powder adsorbent obtained from scrap tyre functionalized with agar-agar (RP-AA) was used to remove methyl violet (MV) dye from synthetic wastewater.The effects of different reaction parameters such as initial MV concentration, contact time and solution temperature on the adsorption of MV onto RP-AA at constant adsorbent dose and pH were investigated.To explain the adsorption character of MV adsorption on RP-AA some kinetic models and adsorption isotherms were applied. Scrap ; Particle size ; Natural rubber ; Particle (ecology) ; Methyl violet Polymer Nanocomposites and Properties ; Dyeing and Modifying Textile Fibers ; Adsorption and biosorption for pollutant removal
Authors: Wouter Masselink | Prayag Murawala
Source: Cells and Development (article, 2024-12-18)
Field: Materials Science — Biomaterials

The evolutionary origin and mechanism of chordate tail regeneration. An ancient tale? Chordate tail regeneration represents the remarkable ability of some chordates to partially or completely regenerate a significant portion of their primary body axis. In this review we will discuss the chordate regenerative ability, what is known about the cellular sources which contribute to the regenerating tail, how various structures such as the spinal cord and vertebral column are re-established, and how scaling of the regenerating tail is regulated. Finally, we propose that tail regeneration is evolutionarily conserved and is fundamentally different from tail development however the origin and mechanism of this process remain elusive. Chordate ; Mechanism (biology) ; Regeneration (biology) ; Evolutionary biology ; Biology ; Environmental ethics ; Paleontology ; History ; Philosophy ; Vertebrate ; Epistemology ; Genetics ; Gene Silk-based biomaterials and applications ; Developmental Biology and Gene Regulation ; Corneal Surgery and Treatments
Authors: Taiji Chida | Tsugumi Seki | Y. Watanabe | Yuichi Niibori
Source: MRS Advances (article, 2024-01-22)
Field: Chemistry — Inorganic Chemistry

Dynamic behavior of sorption of europium onto biotite flakes under the condition of saline groundwater Abstract This study discussed the interaction between Eu and biotite in flakes under the coexistence of Na ions, considering saline groundwater. The sorption experiments were conducted by mixing an Eu solution with Na or K ions and biotite flakes at pH 5. Resultantly, the sorption of Eu gradually increased because of the diffusion into the layered structure of biotite flakes. Thereafter, the sorption amount of Eu with Na ions was less than that without Na ions, and Eu was hardly sorbed with K ions. Additionally, the apparent diffusion coefficients were estimated to be in the order of 10 −13 m 2 /s based on a two-dimensional diffusion model. These values were lower than the effective diffusion coefficients in plutonic rock, which are employed to assess the performance of geological disposal systems. This indicates that the sorption of Eu in plutonic rock is restricted by the diffusion process in biotite flakes. Graphical abstract Sorption ; Biotite ; Diffusion ; Materials science ; Europium ; Ion ; Groundwater ; Quartz ; Geology ; Thermodynamics ; Chemistry ; Adsorption ; Metallurgy ; Physical chemistry ; Geotechnical engineering ; Physics Radioactive element chemistry and processing ; Groundwater flow and contamination studies ; Geochemistry and Elemental Analysis
Authors: R. Santos-Güemes | C.J. Ortiz | Javier Segurado
Source: arXiv (Cornell University) (preprint, 2024-03-14)
Field: Materials Science — Materials Chemistry

An FFT based approach to account for elastic interactions in OkMC: Application to dislocation loops in iron Object kinetic Montecarlo (OkMC) is a fundamental tool for modeling defect evolution in volumes and times far beyond atomistic models. The elastic interaction between defects is classically considered using a dipolar approximation but this approach is limited to simple cases and can be inaccurate for large and close interacting defects. In this work a novel framework is proposed to include "exact" elastic interactions between defects in OkMC valid for any type of defect and anisotropic media. In this method, the elastic interaction energy of a defect is computed by volume integration of its elastic strain multiplied by the stress created by all the other defects, being both fields obtained numerically using a FFT solver. The resulting interaction energies reproduce analytical elastic solutions and show the limited accuracy of dipole approaches for close and large defects. The OkMC framework proposed is used to simulate the evolution in space and time of self-interstitial atoms and dislocation loops in iron. It is found that including the anisotropy has a quantitative effect in the evolution of all the type of defects studied. Regarding dislocation loops, it is observed that using the "exact" interaction energy result in higher interactions than using the dipole approximation for close loops. Fast Fourier transform ; Dislocation ; Computer science ; Materials science ; Physics ; Condensed matter physics ; Algorithm Microstructure and mechanical properties ; Metal Forming Simulation Techniques ; Aluminum Alloys Composites Properties
Authors: Mengxin Chen | Junseok Kim | Seokjun Ham
Source: match Communications in Mathematical and in Computer Chemistry (article, 2024-01-01)
Field: Chemistry — Physical and Theoretical Chemistry

Patterns of a General Chemical Model Involving Degn-Harrison Reaction Scheme This paper reports the pattern formation of a general Degn-Harrison system. We first determine the types and stability of the unique positive equilibrium for the spatially homogeneous system. The equilibrium may be node, focus, or center. Supercritical or subcritical Hopf bifurcation may occur if it is a center. In the sequel, we propose the conditions for the occurrence of Turing instability for the spatially inhomogeneous system. We can theoretically explain that Turing instability exists as the equilibrium transitions from homogeneous stable to inhomogeneous unstable states. Finally, we perform computational experiments to investigate the complex pattern formation of this chemical model. An interesting finding is that if one of the reactants has a high diffusion rate, the pattern formation will be inhibited. Conversely, a low diffusion rate may promote pattern formation. Scheme (mathematics) ; Mathematics ; Computer science ; Mathematical analysis Advanced Physical and Chemical Molecular Interactions ; Chemical Thermodynamics and Molecular Structure
Authors: Paul Raux | David S. Tourigny | Gatien Verley
Source: arXiv (Cornell University) (preprint, 2024-12-19)
Field: Materials Science — Materials Chemistry

Thermodynamic Circuits: Association of thermoelectric converters in stationary non-equilibrium Following up on the recently published circuit theory for thermodynamic devices, we consider networks of Thermo-Electric Converters (TECs) in stationary non-equilibrium. Assuming constant thermoelectric properties, the integration over a finite thickness of the linear local response of the thermoelectric material yields the non-linear current-force characteristics. We show how to derive a choice of nonequilibrium conductance matrix summarizing the current-force characteristics for every available sets of currents and forces. This problem has infinitely many solutions if one considers only thermodynamic constraints. Each solution differs, among others, by the coupling between the currents. Then, we determine the current-force characteristics of the serial (respectively parallel) association of two TECs using the laws of resistance (respectively conductance) matrix addition. For TECs in series, we find current-dependent boundary conditions for each sub-device. Since currents derive from composite potentials, we also associate the derivability and continuity of these potentials at the interfaces with conditions on thermoelectric coefficients. For TECs in parallel, we discuss the possibility of loop currents that are forbidden for the serial association. Thermoelectric effect ; TEC ; Current (fluid) ; Converters ; Internal resistance ; Conductance ; Electronic circuit ; Boundary (topology) ; Electrical resistance and conductance ; Short circuit ; Materials science ; Mechanics ; Mathematics ; Thermodynamics ; Electrical engineering ; Condensed matter physics ; Physics ; Voltage ; Mathematical analysis ; Engineering ; Composite material Advanced Thermoelectric Materials and Devices ; Advanced Thermodynamics and Statistical Mechanics ; Thermal properties of materials
Authors: Juan Ignacio GONZALEZ PACHECO | Mariela Beatriz MALDONADO
Source: AJEA (article, 2024-10-08)
Field: Chemistry — Analytical Chemistry

Estudio del Fenómeno de Difusión de Colorantes Naturales en Cerezas en Conserva Elaboradas con Polialcoholes Esta tesis investiga la viabilidad de reemplazar los colorantes sintéticos en las cerezas confitadas con pigmentos naturales extraídos del rábano, la remolacha y la gardenia, abordando la creciente demanda de los consumidores de productos alimenticios más saludables y naturales. El estudio abarca un análisis de la estabilidad y la cinética de difusión de estos colorantes naturales dentro de la matriz de la cereza durante un proceso de confitado. La primera fase de la investigación se centra en caracterizar la estabilidad de los colorantes naturales seleccionados en diversas condiciones de procesamiento, como su resistencia a las fluctuaciones de temperatura, la exposición a la luz y las variaciones de pH. La segunda fase profundiza en el intrincado proceso de difusión del colorante dentro de los tejidos de la cereza. Empleando una combinación de técnicas experimentales y modelos matemáticos, se cuantificó la cinética de difusión de cada colorante en pulpa y piel de la cereza durante el endulzamiento con una formulación de 50%sacarosa/50%xilitol de 35 Bx. Esto implicó analizar la influencia de las variables clave de procesamiento, como la temperatura (40, 50 y 60°C), la concentración de colorante (119, 238 y 357 ppm) durante el tiempo de impregnación, en la velocidad de transporte y el grado de difusión del pigmento. Al dilucidar los mecanismos subyacentes que rigen el transporte del colorante dentro de la matriz de la fruta, se estableció un modelo matemático predictivo (1D) como primera aproximación, quedando avanzar en más dimensiones (2D y 3D), para optimizar el proceso de confitado. Parte de la metodología y resultados presentados ha sido publicada en la revista Scientific Reports de Nature. Humanities ; Environmental science ; Philosophy Dye analysis and toxicity
Authors: Michael J. Plank | Matthew J. Simpson
Source: arXiv (Cornell University) (preprint, 2024-03-04)
Field: Chemistry — Physical and Theoretical Chemistry

Structured methods for parameter inference and uncertainty quantification for mechanistic models in the life sciences Parameter inference and uncertainty quantification are important steps when relating mathematical models to real-world observations, and when estimating uncertainty in model predictions. However, methods for doing this can be computationally expensive, particularly when the number of unknown model parameters is large. The aim of this study is to develop and test an efficient profile likelihood-based method, which takes advantage of the structure of the mathematical model being used. We do this by identifying specific parameters that affect model output in a known way, such as a linear scaling. We illustrate the method by applying it to three caricature models from different areas of the life sciences: (i) a predator-prey model from ecology; (ii) a compartment-based epidemic model from health sciences; and, (iii) an advection-diffusion-reaction model describing transport of dissolved solutes from environmental science. We show that the new method produces results of comparable accuracy to existing profile likelihood methods, but with substantially fewer evaluations of the forward model. We conclude that our method could provide a much more efficient approach to parameter inference for models where a structured approach is feasible. Code to apply the new method to user-supplied models and data is provided via a publicly accessible repository. Inference ; Uncertainty quantification ; Computer science ; Management science ; Econometrics ; Machine learning ; Artificial intelligence ; Mathematics ; Economics thermodynamics and calorimetric analyses ; Protein Structure and Dynamics ; Gene Regulatory Network Analysis
Authors: Jingheng Fu | Mikael Kuisma | Ask Hjorth Larsen | Kohei Shinohara | Atsushi Togo | Kristian S Thygesen
Source: Institutional Repositories DataBase (IRDB) (article, 2024-07-01)
Field: Materials Science — Materials Chemistry

Symmetry classification of 2D materials: layer groups versus space groups The symmetry of a crystal structure with a three dimensional (3D) lattice can be classified by one of the 230 space group types. For some types of crystals, e.g. crystalline films, surfaces, or planar interfaces, it is more appropriate to assume a 2D lattice. With this assumption the structure can be classified by one of the 80 layer group types. We have implemented an algorithm to determine the layer group type of a 3D structure with a 2D lattice, and applied it to more than 15 000 monolayer structures in the Computational 2D Materials (C2DB) database. We compare the classification of monolayers by layer groups and space groups, respectively. The latter is defined as the space group of the 3D bulk structure obtained by repeating the monolayer periodically in the direction perpendicular to the 2D lattice (AA-stacking). By this correspondence, nine pairs of layer group types are mapped to the same space group type due to the inability of the space group to distinguish the in-plane and out-of-plane axes. In total 18% of the monolayers in the C2DB belong to one of these layer group pairs and are thus not properly classified by the space group type. Our result shows that classifying 2D materials via layer groups is more accurate and outperforms the commonly used space group classification scheme. Layer (electronics) ; Space (punctuation) ; Group (periodic table) ; Symmetry (geometry) ; Group theory ; Symmetry group 2D Materials and Applications ; Topological Materials and Phenomena ; Nonlocal and gradient elasticity in micro/nano structures
Authors: Bartosz Opitek | P. L. Żak | J. Lelito | Vincent Vignal
Source: Applied Sciences (article, 2024-04-03)
Field: Materials Science — Biomaterials

Modelling Crystalline α-Mg Phase Growth in an Amorphous Alloy Mg72Zn28 A model of α-Mg grain growth in an amorphous Mg72Zn28 alloy matrix was developed together with numerical software. Its application enables tracking the growth process of the α-Mg phase in an amorphous alloy. The model was based on the diffusion-driven growth of α-Mg in an amorphous alloy under appropriate boundary conditions at an isothermal annealing temperature and taking into account the presence of a grain with an initial radius of 1 nm. The numerical model was based on a mathematical model of heat flow, described by the Fourier–Kirchhoff equation, and diffusion, described by Fick’s second law. The initial boundary conditions necessary to simulate grain growth in the amorphous phase were established. The results of the numerical simulation indicate grain growth with increasing isothermal annealing temperature and increasing isothermal annealing time. Materials science ; Annealing (glass) ; Isothermal process ; Grain growth ; Amorphous solid ; Alloy ; Amorphous metal ; Metallurgy ; Grain boundary ; Thermodynamics ; Mechanics ; Grain size ; Crystallography ; Microstructure ; Physics ; Chemistry Magnesium Alloys: Properties and Applications ; Material Properties and Applications ; Metallic Glasses and Amorphous Alloys
Authors: Yutaka Kinoshita | Nariya Uchida
Source: arXiv (Cornell University) (preprint, 2024-04-12)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Active nematic liquid crystals under a quenched random field Coupling between flow and orientation is a central issue in understanding the collective dynamics of active biofilaments and cells. Active stresses generated by motor activity destroy (quasi-)long-range orientational order and induce chaotic flows with many vortices. In cellular and subcellular environment, alignment is also hindered by heterogeneous filamentous structures in extracellular matrix and various intracellular organelles. Here we address the effects of a quenched random field on the flow patterns and orientational order in two-dimensional active nematic liquid crystals. We find that the director dynamics becomes frozen above a critical disorder strength. For sufficiently strong randomness, the orientational correlation function decays exponentially with distance, reproducing the behavior of passive random-field nematics. In contrast, the flow velocity decreases only gradually with increasing disorder, and exhibits a logarithmic spatial correlation under strong randomness. We identify the threshold between the activity- and disorder-dominated regimes and examine its dependence on the activity parameter. Liquid crystal ; Condensed matter physics ; Field (mathematics) ; Materials science ; Physics ; Mathematics ; Pure mathematics Liquid Crystal Research Advancements