jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Anne Tanguy
Source: Comptes Rendus Physique (article, 2023-11-13)
Field: Materials Science — Materials Chemistry

Vibrations and Heat Transfer in Glasses: The Role Played by Disorder Amorphous materials are also distinguished from crystals by their thermal properties. The structural disorder seems to be responsible both for a significant increase in heat capacity compared to crystals of the same composition, but also for a significant decrease in thermal conductivity. The temperature dependence of thermal conductivity, unusual for common interpretations of solid-state physics, gave rise to a lot of debates. We review in this article different interpretations of thermal conductivity in amorphous materials. We show finally that the temperature dependence of thermal conductivity in dielectric materials can be understood by relating it to the disorder-dependent harmonic vibrational eigenmodes. Thermal conductivity ; Amorphous solid ; Materials science ; Dielectric ; Heat transfer ; Thermal ; Condensed matter physics ; Heat capacity ; Thermal conduction ; Thermodynamics ; Phonon ; Thermal effusivity ; Thermal contact conductance ; Thermal resistance ; Composite material ; Chemistry ; Physics ; Crystallography Material Dynamics and Properties ; Phase-change materials and chalcogenides ; High-pressure geophysics and materials
Authors: Eyass Massarwa | Christophe Czarnota | A. Molinari
Source: International Journal of Impact Engineering (article, 2023-11-02)
Field: Materials Science — Materials Chemistry

Finite element modeling of steady plastic shockwaves in porous metals: Role of size, shape, and spatial distribution of voids Microscale chemistry ; Materials science ; Porosity ; Shock (circulatory) ; Porous medium ; Finite element method ; Plasticity ; Mechanics ; Shock response spectrum ; Acceleration ; Composite material ; Structural engineering ; Classical mechanics ; Engineering ; Physics High-Velocity Impact and Material Behavior ; Particle Dynamics in Fluid Flows ; Structural Response to Dynamic Loads
Authors: Yejiao Shi | Honggang Hu
Source: PubMed (article, 2023-01-01)
Field: Materials Science — Biomaterials

AI accelerated discovery of self-assembling peptides. Drug discovery ; Computational biology ; Data science ; Nanotechnology ; Chemistry ; Computer science ; Materials science ; Biology ; Biochemistry Supramolecular Self-Assembly in Materials ; Chemical Synthesis and Analysis ; Advanced biosensing and bioanalysis techniques
Authors: Samsudin Anis | Deni Fajar Fitriyana | Aldias Bahatmaka | Muhammad Choirul Anwar | Arsyad Zanadin Ramadhan | Fajar Chairul Anam | Raffanel Adi Permana | Ahmad Jazilussurur Hakim | Natalino Fonseca Da Silva Guterres | Mateus De Sousa Da Silva
Source: JOURNAL OF RENEWABLE MATERIALS (article, 2023-01-01)
Field: Chemistry — Inorganic Chemistry

Effect of Adhesive Type on the Quality of Coconut Shell Charcoal Briquettes Prepared by the Screw Extruder Machine Indonesia is one of the largest coconut-producing countries in the world. The utilization of coconut shell waste into briquettes will increase the selling value and become a great export opportunity. However, the effect of adhesives on the quality of coconut shell charcoal briquettes made using screw extruder machine has not been widely studied. This study aims to determine the effect of adhesive type on the quality of coconut shell charcoal briquettes. The process of fabricating briquettes in this study included crushing, mixing, blending, pressing, and drying. In the mixing process, 3 types of adhesives were used, namely tapioca flour (Briquette_1), cassava flour (Briquette_2), and modified cassava flour (Briquette_3) with a concentration of 5% of the weight of coconut shell charcoal powders. The quality of the resulting briquettes and commercial briquettes will be evaluated by moisture content, ash content, volatile matter, fixed carbon, calorific value, density, compressive, and drop test testing. The results of this research showed that the type of adhesive had a significant effect on the quality of the briquettes produced. Specimen Briquette_1 had better quality than commercial briquettes (Briquette_4) and other briquette specimens. The test results showed that Briquette_1 produced briquettes with better compressive strength and friability than the other specimens, at 6.95 N/mm2 and 4.44%, respectively. The moisture content, ash content, fixed carbon, and calorific value of Briquette_1 have met the requirements set by the Indonesian National Standard (SNI) number 01-6235-2000. Meanwhile, the volatile matter content and density of Briquette_1 are by the standards of Japan and the United States America (USA). Briquette ; Charcoal ; Heat of combustion ; Pulp and paper industry ; Materials science ; Moisture ; Adhesive ; Waste management ; Composite material ; Metallurgy ; Combustion ; Coal ; Chemistry ; Engineering Coconut Research and Applications ; Thermochemical Biomass Conversion Processes
Authors: Z S Baird | V Oja | O Järvik
Source: Oil Shale (article, 2023-02-02)
Field: Chemistry — Organic Chemistry

The composition of kukersite shale oil Pyrolysis oils are usually considered as substitutes for crude oil; however, they can also be sources of valuable compounds. One such pyrolysis oil is shale oil obtained by pyrolysis of kukersite oil shale. Kukersite shale oil consists mainly of aromatic rings with straight alkyl side chains. For samples with comparable boiling point distributions, kukersite shale oil has a higher proportion of aromatic rings than petroleum and many other shale oils. Sulfur, nitrogen, and oxygen are often incorporated into the ring structures, with much of the oxygen also present as phenolic hydroxyl groups. To evaluate the potential for producing some specific compounds from kukersite shale oil foundational data on the composition is needed. In this article, new experimental data on the elemental composition and infrared spectrum of kukersite shale oil is analyzed to investigate its composition. To get detailed information on how the composition of the oil changes depending on the average molecular weight of the oil fraction, the shale oil was separated into narrow boiling fractions using distillation. This gives more detailed data on different portions of the oil than earlier datasets. Additionally, this data is for oil produced from newer solid heat carrier retorts. The results show that the nitrogen content in kukersite shale oil increases with the boiling temperature, with the heaviest fractions containing about 0.3 wt%. Sulfur content reaches a maximum of almost 2 wt% for fractions boiling between 150 and 190 Â°C, and heavier fractions contain about 0.7 wt%. Similarly, the proportion of hydroxyl groups in kukersite shale oil peaks in the fraction boiling at about 320 Â°C, with heavier fractions containing more aromatic and alkyl functional groups. The elemental composition of kukersite shale oil is also compared to that of other shale oils. Oil shale ; Composition (language) ; Geology ; Petroleum engineering ; Geochemistry ; Environmental science ; Paleontology ; Art Chemical Thermodynamics and Molecular Structure ; Crystallization and Solubility Studies ; Coal and Coke Industries Research
Authors: Edward Curran Eggertson | Francesca Venturini
Source: Sensors (article, 2023-09-02)
Field: Chemistry — Analytical Chemistry

Resonant Raman Spectroscopy of Carotenoids in Aging of Extra Virgin Olive Oil This work uses resonant Raman spectroscopy (RRS) to investigate changes in carotenoid concentration in extra virgin olive oil (EVOO) as it oxidizes under accelerated thermal aging. Carotenoids are nutritious antioxidants and biomarkers that represent the general quality of olive oil. HPLC is the conventional method used to determine the concentration of carotenoids, but it is expensive, time-consuming, and requires sample handling. A simple optical technique for estimating carotenoid concentration in extra virgin olive oil is, therefore, desirable. This work shows that the normally weak carotenoid signal is strongly amplified when using the resonant Raman technique. The aging and oxidation of EVOO decreases the Raman intensities associated with carotenoids and increases the fluorescence and Raman intensities associated with fatty acids. From these quantities, two Raman intensity ratios are presented as indicators of the effects of aging. Carotenoid ; Raman spectroscopy ; Olive oil ; Chemistry ; Fluorescence ; Food science ; Analytical Chemistry (journal) ; Chromatography ; Materials science ; Optics ; Physics Spectroscopy and Chemometric Analyses ; Edible Oils Quality and Analysis ; Spectroscopy Techniques in Biomedical and Chemical Research
Authors: Rui Li | Huaiwen Wang | Bingbing Shen | Xingwei Yao
Source: Agriculture (article, 2023-12-08)
Field: Chemistry — Analytical Chemistry

Study on Dissipation Law of Pesticides in Cauliflower Based on Hyperspectral Image Technique In order to rapidly and non-destructively detect the residual rate of emamectin benzoate+indoxacarb pesticides on cauliflower, a study was conducted using hyperspectral technology to investigate the dissipation law of this pesticide over time. Hyperspectral imaging was employed to capture spectral data from cauliflower samples with and without the pesticide, focusing on the region of interest. The spectral data, consisting of 216 bands (ranging from 950 nm to 1666 nm), were preprocessed using techniques such as Savitzky–Golay convolution smoothing (S-G), multivariate scattering correction (MSC), and standard normal variate (SNV). Next, characteristic spectra for each pesticide were extracted using the competitive adaptive reweighted sampling algorithm (CARS). This study utilized the partial least squares (PLS) algorithm to construct a discriminative model aimed at identifying pesticide residues on cauliflower. The accuracy of the hyperspectral imaging technique was validated by comparing the results with those obtained through chromatography. The PLS model, optimized using the SNV method, exhibited the highest discriminant accuracy, achieving a recognition rate of 100%. The residual rate of indoxacarb detected through hyperspectral technology closely corresponded to the results obtained through chromatography. It was found that the discrepancy in the half-life of pesticides as detected by hyperspectral and chromatographic methods is a mere 0.14 days. These findings highlight the potential of hyperspectral imaging technology for studying pesticide dissipation on cauliflower and detecting pesticide residues. Hyperspectral imaging ; Pesticide ; Pesticide residue ; Pattern recognition (psychology) ; Mathematics ; Residual ; Biological system ; Artificial intelligence ; Computer science ; Algorithm ; Biology ; Agronomy Spectroscopy and Chemometric Analyses ; Pesticide Residue Analysis and Safety ; Water Quality Monitoring and Analysis
Authors: Wen-Ti Guo | Zhigao Huang | Jian‐Min Zhang
Source: Physical review. B./Physical review. B (article, 2023-09-25)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Thermal and mechanical properties and the structural phase transition under pressure in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>A</mml:mi><mml:msub><mml:mi>In</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mi>As</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mo>(</mml:mo><mml:mi>A</mml:mi><mml:mo>=</mml:mo><mml:mi>Ca</mml:mi><mml:mo>,</mml:mo><mml:mo> </mml:mo><mml:mi>Sr</mml:mi><mml:mo>,</mml:mo><mml:mo> </mml:mo><mml:mi>Ba</mml:mi><mml:mo>)</mml:mo></mml:math> Experimental results that ${\mathrm{BaIn}}_{2}{\mathrm{As}}_{2}$ and $\mathrm{Ca}(\mathrm{Sr}){\mathrm{In}}_{2}{\mathrm{As}}_{2}$, which are the same class of alkali metal compounds, belong to different structural phases have puzzled the current materials physics community. Here, we investigate the pressure-induced structural phase transition of $A{\mathrm{In}}_{2}{\mathrm{As}}_{2}$ and its accompanying improvement in mechanical and thermal properties. Firstly, the structural stability of the materials and their structural phase transitions under pressure are characterized by enthalpy and double checking by phonon dispersion spectrum. We also confirm the structural phase transitions of the hexagonal and monoclinic phases from a group-theoretic point of view, associating their symmetry operations using transformation matrices. In terms of mechanical properties, we propose an effective scheme for pressure modulation of the anisotropy of $A{\mathrm{In}}_{2}{\mathrm{As}}_{2}$ materials and to induce the transformation of $A{\mathrm{In}}_{2}{\mathrm{As}}_{2}$ from isotropic to anisotropic (hexagonal) and from brittle to ductile (hexagonal and monoclinic). Meanwhile, we find the negative Poisson's ratio phenomenon under compression and tension, which is favorable for a wide range of applications of this series of materials in aerospace, medicine, sensors, etc. In terms of thermal properties, applying pressure will enhance the structural phase transition temperature of $A{\mathrm{In}}_{2}{\mathrm{As}}_{2}$ materials to near room temperature. We further give direct evidence of phonon softening based on group velocity calculations and reveal that phonon softening prevents the heat capacity from reaching the Dulong-Petit limit. Our study provides a theoretical basis for selecting stable structural phases and pioneering thermodynamic property studies of the thermoelectric topological candidate material $A{\mathrm{In}}_{2}{\mathrm{As}}_{2}$. Monoclinic crystal system ; Phonon ; Phase transition ; Materials science ; Condensed matter physics ; Anisotropy ; Phase (matter) ; Crystallography ; Thermodynamics ; Physics ; Crystal structure ; Chemistry ; Quantum mechanics Iron-based superconductors research ; Rare-earth and actinide compounds ; Advanced Thermoelectric Materials and Devices
Authors: Robert J. Meier | Paul R. Rablen
Source: Thermo (article, 2023-05-26)
Field: Chemistry — Organic Chemistry

Group Contribution Revisited: The Enthalpy of Formation of Organic Compounds with “Chemical Accuracy” Part IV Group contribution (GC) methods to predict thermochemical properties are eminently important to process design. Following earlier work which presented a GC model in which, for the first time, chemical accuracy (1 kcal/mol or 4 kJ/mol) was accomplished, we here discuss classes of molecules for which the traditional GC approach does not hold, i.e., many results are beyond chemical accuracy. We report new ring-strain-related parameters which enable us to evaluate the heat of formation of alkyl-substituted cycloalkanes. In addition, the definition of the appropriate group size is important to obtain reliable and accurate data for systems in which the electron density varies continuously but slowly between related species. For this and in the case of ring strain, G4 quantum calculations are shown to be able to provide reliable heats of formation which provide the quantitative data which we can use, in the case of absence of experimental data, to establish group and nearest-neighbour interaction parameters to extend the range of applicability of the GC method whilst retaining chemical accuracy. We also found that the strong van der Waals that overlap in highly congested branched alkanes can be qualitatively investigated by applying DFT quantum calculations, which can provide an indication of the GC approach being inappropriate. van der Waals force ; Standard enthalpy of formation ; Chemistry ; Quantum chemical ; Enthalpy ; Thermodynamics ; Ring (chemistry) ; Group (periodic table) ; Molecule ; Group contribution method ; Computational chemistry ; Work (physics) ; Standard enthalpy change of formation ; Range (aeronautics) ; Alkyl ; Density functional theory ; Physical chemistry ; Organic chemistry ; Materials science ; Physics Chemical Thermodynamics and Molecular Structure ; Phase Equilibria and Thermodynamics ; Advanced Chemical Physics Studies
Authors: Trent R. Graham | Brandy N. Gartman | Anjelica Bautista | Lindsay E.I. Irwin | Eden Shelby | Danielle Saunders | Timothy J. Johnson | Mark K. Murphy | Nicolas Uhnak | Andrew M. Ritzmann | James M. Bowen
Source: Journal of Molecular Liquids (article, 2023-07-19)
Field: Chemistry — Inorganic Chemistry

Spectroscopic features of dissolved iodine in pristine and gamma-irradiated nitric acid solutions Chemistry ; Spectroscopy ; Raman spectroscopy ; Fourier transform infrared spectroscopy ; Iodide ; Nitric acid ; Iodine ; Iodate ; Analytical Chemistry (journal) ; Inorganic chemistry ; Photochemistry ; Organic chemistry ; Optics Radioactive element chemistry and processing ; Radioactive contamination and transfer ; Nuclear Materials and Properties
Authors: Yang Hu | Dennis M. Kochmann
Source: Journal of Materials Science (article, 2023-02-18)
Field: Materials Science — Biomaterials

Atomistic insight into three-dimensional twin embryo growth in Mg alloys Abstract Magnesium (Mg) alloys are essential for industrial applications but poorly understood from a mechanistic perspective, while a comprehensive understanding of their mechanical behavior can guarantee a more efficient alloy design as well as a greater application potential. As one of the key deformation mechanisms in Mg and Mg alloys, twinning is investigated in this work. Molecular dynamics simulations are used to perform a systematic study of the effect of alloying elements and solute compositions on twin embryo growth in nine Mg alloys. The alloying elements include Al, Zn, Li, Ca, Pb, Nd, Ce, Sn, and Y, covering a wide range of element properties such as lattice constant, bulk/shear modulus, and cohesive energy. We demonstrate a faster migration of the dark side than the bright side of twin embryos in both pure Mg and Mg alloys. All solute atoms tested in this work exhibit a pinning effect on the motion of twin facets on the dark side. The motion of facets on the bright side, particularly twin boundaries, can be accelerated by solutes. Therefore, the majority of solutes can reduce the velocity difference between the dark side and the bright side of the twin. The overall twin embryo growth is restricted in most alloys except Mg–Y, Mg–Li and Mg–Nd with certain solute concentrations. Our results present important insight for tailoring twin structures and hence the mechanical properties of Mg alloys. Graphical abstract Crystal twinning ; Materials science ; Alloy ; Molecular dynamics ; Chemical physics ; Crystallography ; Metallurgy ; Microstructure ; Computational chemistry ; Chemistry Magnesium Alloys: Properties and Applications ; Aluminum Alloys Composites Properties ; Hydrogen Storage and Materials
Authors: Selvaraj Sengottiyan | Alicja Mikołajczyk | Tomasz Puzyn
Source: International Journal of Molecular Sciences (article, 2023-02-09)
Field: Materials Science — Biomaterials

How Does the Study MD of pH-Dependent Exposure of Nanoparticles Affect Cellular Uptake of Anticancer Drugs? The lack of knowledge about the uptake of NPs by biological cells poses a significant problem for drug delivery. For this reason, designing an appropriate model is the main challenge for modelers. To address this problem, molecular modeling studies that can describe the mechanism of cellular uptake of drug-loaded nanoparticles have been conducted in recent decades. In this context, we developed three different models for the amphipathic nature of drug-loaded nanoparticles (MTX-SS-γ-PGA), whose cellular uptake mechanism was predicted by molecular dynamics studies. Many factors affect nanoparticle uptake, including nanoparticle physicochemical properties, protein-particle interactions, and subsequent agglomeration, diffusion, and sedimentation. Therefore, the scientific community needs to understand how these factors can be controlled and the NP uptake of nanoparticles. Based on these considerations, in this study, we investigated for the first time the effects of the selected physicochemical properties of the anticancer drug methotrexate (MTX) grafted with hydrophilic-γ-polyglutamic acid (MTX-SS-γ-PGA) on its cellular uptake at different pH values. To answer this question, we developed three theoretical models describing drug-loaded nanoparticles (MTX-SS-γ-PGA) at three different pH values, such as (1) pH 7.0 (the so-called neutral pH model), (2) pH 6.4 (the so-called tumor pH model), and (3) pH 2.0 (the so-called stomach pH model). Exceptionally, the electron density profile shows that the tumor model interacts more strongly with the head groups of the lipid bilayer than the other models due to charge fluctuations. Hydrogen bonding and RDF analyses provide information about the solution of the NPs with water and their interaction with the lipid bilayer. Finally, dipole moment and HOMO-LUMO analysis showed the free energy of the solution in the water phase and chemical reactivity, which are particularly useful for determining the cellular uptake of the NPs. The proposed study provides fundamental insights into molecular dynamics (MD) that will allow researchers to determine the influence of pH, structure, charge, and energetics of NPs on the cellular uptake of anticancer drugs. We believe that our current study will be useful in developing a new model for drug delivery to cancer cells with a much more efficient and less time-consuming model. Nanoparticle ; Chemistry ; Context (archaeology) ; Biophysics ; Molecular dynamics ; Drug delivery ; Drug ; Amphiphile ; Lipid bilayer ; Nanotechnology ; Biochemistry ; Pharmacology ; Computational chemistry ; Materials science ; Organic chemistry ; Polymer Nanoparticle-Based Drug Delivery ; RNA Interference and Gene Delivery ; Cancer Research and Treatments
Authors: Hao-Chen Wang | Zhi‐Hao Wang | Xuan‐Yan Chen | Su‐Huai Wei | Wenguang Zhu | Xie Zhang
Source: Chinese Physics Letters (article, 2023-03-13)
Field: Materials Science — Materials Chemistry

Competition between Stepwise Polarization Switching and Chirality Coupling in Ferroelectric GeS Nanotubes Ferroelectricity of group-IV chalcogenides MX ( M = Ge, Sn; X = Se, S) monolayers has been extensively investigated. However, how the ferroelectricity evolves in their one-dimensional nanotubes remains largely unclear. Employing an accurate deep-learning interatomic potential of first-principles precision, we uncover a general stepwise mechanism for polarization switching in zigzag and chiral GeS nanotubes, which has an energy barrier that is substantially lower than the one associated with the conventional one-step switching mechanism. The switching barrier (per atom) gradually decreases with increasing the number of intermediate steps and converges to a value that is almost independent of the tube diameter. In the chiral GeS nanotubes, the switching path of polarization with chirality coupling is preferred at less intermediate steps. This study unveils novel ferroelectric switching behaviors in one-dimensional nanotubes, which is critical to coupling ferroelectricity and chirality. Ferroelectricity ; Zigzag ; Materials science ; Chirality (physics) ; Polarization (electrochemistry) ; Condensed matter physics ; Monolayer ; Nanotube ; Coupling (piping) ; Nanotechnology ; Chemical physics ; Dielectric ; Optoelectronics ; Carbon nanotube ; Physics ; Quantum mechanics ; Chemistry ; Composite material 2D Materials and Applications ; Machine Learning in Materials Science ; Solid-state spectroscopy and crystallography