jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Fadoua Khmaissia | Hichem Frigui | Mahendra K. Sunkara | Jacek B. Jasiński | Alejandro Martínez García | Tom Pace | Madhu Menon
Source: Computational Materials Science (article, 2018-02-22)
Field: Materials Science — Materials Chemistry

Accelerating band gap prediction for solar materials using feature selection and regression techniques Feature selection ; Band gap ; Lasso (programming language) ; Solar energy ; Computer science ; Feature (linguistics) ; Regression ; Energy (signal processing) ; Regression analysis ; Machine learning ; Artificial intelligence ; Materials science ; Mathematics ; Engineering ; Statistics ; Optoelectronics Machine Learning in Materials Science ; Chalcogenide Semiconductor Thin Films
Authors: Nick Gerrits | Davide Migliorini | Geert–Jan Kroes
Source: The Journal of Chemical Physics (article, 2018-12-11)
Field: Materials Science — Materials Chemistry

Dissociation of CHD3 on Cu(111), Cu(211), and single atom alloys of Cu(111) In order to model accurately reactions of polyatomic molecules with metal surfaces important for heterogeneous catalysis in industry, the Specific Reaction Parameter (SRP) approach to density functional theory has been developed. This approach has been shown to describe the dissociation of CHD<sub>3</sub> on Ni(111), Pt(111), and Pt(211) with chemical accuracy. In this work, predictions have been made for the reaction of CHD<sub>3</sub> on Cu(111) and Cu(211) using barriers, elbow plots, and <i>ab initio</i> molecular dynamics. Future experiments could hopefully prove the transferability of the SRP functional to systems in which methane reacts with flat and stepped surfaces of adjacent groups of the periodic table, by comparison with our predictions. Moreover, the effect of a so-called single atom alloy on the reactivity of methane is investigated by making predictions for CHD<sub>3</sub> on Pt-Cu(111) and Pd-Cu(111). It is found that the reactivity is only increased for Pt-Cu(111) near the alloyed atom, which is not only caused by the lowering of the barrier height but also by changes in the dynamical pathway and reduction of energy transfer from methane to the surface. Dissociation (chemistry) ; Copper ; Atom (system on chip) ; Chemistry ; Materials science ; Crystallography ; Metallurgy ; Physical chemistry ; Computer science ; Operating system Catalytic Processes in Materials Science ; Advanced Chemical Physics Studies ; Catalysis and Oxidation Reactions
Authors: Victoria Cortés | José Manuel Barat Baviera | Pau Talens | J. Blasco | Marı́a Jesús Lerma-García
Source: Food Control (article, 2018-07-17)
Field: Chemistry — Analytical Chemistry

A comparison between NIR and ATR-FTIR spectroscopy for varietal differentiation of Spanish intact almonds Fourier transform infrared spectroscopy ; Quadratic classifier ; Linear discriminant analysis ; Mathematics ; Near-infrared spectroscopy ; Attenuated total reflection ; Discriminant ; Spectroscopy ; Fourier transform ; Pattern recognition (psychology) ; Chemistry ; Artificial intelligence ; Biological system ; Analytical Chemistry (journal) ; Computer science ; Chromatography ; Statistics ; Physics ; Biology ; Support vector machine ; Optics Spectroscopy and Chemometric Analyses ; Nuts composition and effects ; Bee Products Chemical Analysis
Authors: Pulong Geng | Jiancheng Song | Muqin Tian | Zhipeng Lei | Yakun Du
Source: AIP Advances (article, 2018-02-01)
Field: Materials Science — Materials Chemistry

Influence of thermal aging on AC leakage current in XLPE insulation Cross-linked polyethylene (XLPE) has been widely used as cable insulation material because of its excellent dielectric properties, thermal stability and solvent resistance. To understand the influence of thermal aging on AC leakage current in XLPE insulation, all XLPE specimens were aged in oven in temperature range from 120 °C to 150 °C, and a series of tests were conducted on these XLPE specimens in different aging stages to measure the characteristic parameters, such as complex permittivity, leakage current and complex dielectric modulus. In the experiments, the effects of thermal aging, temperature and frequency on the AC leakage current in XLPE insulation were studied by analyzing complex dielectric constant and dielectric relaxation modulus spectrum, the change of relaxation peak and activation energy. It has been found that the active part of leakage current increases sharply with the increase of aging degree, and the test temperature and frequency have an influence on AC leakage current but the influence of test temperature is mainly reflected in the low frequency region. In addition, it has been shown by the experiments that the reactive part of leakage current exhibits a strong frequency dependent characteristic in the testing frequency range from 10-2 Hz to 105 Hz, but the influence of test temperature and thermal aging on it is relatively small. Materials science ; Composite material ; Polyethylene ; Leakage (economics) ; Dielectric ; Cross-linked polyethylene ; Permittivity ; Atmospheric temperature range ; Activation energy ; Dielectric loss ; Thermodynamics ; Optoelectronics ; Chemistry High voltage insulation and dielectric phenomena ; Dielectric properties of ceramics ; Dielectric materials and actuators
Authors: Rodrigo Freitas | Robert E. Rudd | Mark Asta | Timofey Frolov
Source: Physical Review Materials (article, 2018-09-10)
Field: Materials Science — Materials Chemistry

Free energy of grain boundary phases: Atomistic calculations for <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi mathvariant="normal">Σ</mml:mi><mml:mn>5</mml:mn><mml:mo>(</mml:mo><mml:mn>310</mml:mn><mml:mo>)</mml:mo><mml:mo>[</mml:mo><mml:mn>001</mml:mn><mml:mo>]</mml:mo></mml:mrow></mml:math> grain boundary in Cu Atomistic simulations are employed to demonstrate the existence of a well-defined thermodynamic phase transformation between grain boundary (GB) phases with different atomic structures. The free energy of different interface structures for an embedded-atom-method model of the $\mathrm{\ensuremath{\Sigma}}5(310)[001]$ symmetric tilt boundary in elemental Cu is computed using the nonequilibrium Frenkel-Ladd thermodynamic integration method through molecular dynamics simulations. It is shown that the free-energy curves predict a temperature-induced first-order interfacial phase transition in the GB structure in agreement with computational studies of the same model system. Moreover, the role of vibrational entropy in the stabilization of the high-temperature GB phase is clarified. The calculated results are able to determine the GB phase stability at homologous temperatures less than 0.5, a temperature range particularly important given the limitation of the methods available hitherto in modeling GB phase transitions at low temperatures. The calculation of GB free energies complements currently available 0 K GB structure search methods, making feasible the characterization of GB phase diagrams. Grain boundary ; Non-equilibrium thermodynamics ; Molecular dynamics ; Phase (matter) ; Thermodynamic integration ; Phase boundary ; Phase transition ; Boundary (topology) ; Entropy (arrow of time) Microstructure and mechanical properties ; Copper Interconnects and Reliability ; Fusion materials and technologies
Authors: Amir Tabzar | Mohammad Fathinasab | Afshin Salehi | Babak Bahrami | Amir H. Mohammadi
Source: Oil & Gas Science and Technology – Revue d’IFP Energies nouvelles (article, 2018-01-01)
Field: Chemistry — Analytical Chemistry

Multiphase flow modeling of asphaltene precipitation and deposition Asphaltene precipitation in reservoirs during production and Enhanced Oil Recovery (EOR) can cause serious problems that lead to reduction of reservoir fluid production. In order to study asphaltene tendency to precipitate and change in flow rate as a function of distance from wellbore, an equation of state (Peng-Robinson) based model namely Nghiem et al. ’s model has been employed in this study. The heaviest components of crude oil are separated into two parts: The first portion is considered as non-precipitating component (C 31A+ ) and the second one is considered as precipitating component (C 31B+ ) and the precipitated asphaltene is considered as pure solid. For determination of the acentric factor and critical properties, Lee-Kesler and Twu correlations are employed, respectively. In this study, a multiphase flow (oil, gas and asphaltene) model for an asphaltenic crude oil for which asphaltene is considered as solid particles (precipitated, flocculated and deposited particles), has been developed. Furthermore, effect of asphaltene precipitation on porosity and permeability reduction has been studied. Results of this study indicate that asphaltene tendency to precipitate increases and permeability of porous medium decreases by increasing oil flow rate in under-saturated oil reservoirs and dropping reservoir pressure under bubble point pressure. On the other hand, asphaltene tendency to precipitate decreases with pressure reduction to a level lower than bubble point pressure where asphaltene starts to dissolve back into oil phase. Moreover, it is observed that precipitation zone around the wellbore develops with time as pressure declines to bubble point pressure (production rate increases up). Also, there is an equilibrium area near wellbore region at which reservoir fluid properties such as UAOP (Upper Asphaltene Onset Pressure) and LAOP (Lower Asphaltene Onset Pressure) are constant and independent of the distance from wellbore. Asphaltene ; Bubble point ; Permeability (electromagnetism) ; Multiphase flow ; Precipitation ; Bubble ; Petroleum engineering ; Chemical engineering ; Materials science ; Chemistry ; Chromatography ; Thermodynamics ; Geology ; Organic chemistry ; Mechanics Petroleum Processing and Analysis ; Enhanced Oil Recovery Techniques ; Hydrocarbon exploration and reservoir analysis
Authors: Anna Dankowska | Wojciech Kowalewski
Source: European Food Research and Technology (article, 2018-11-10)
Field: Chemistry — Analytical Chemistry

Comparison of different classification methods for analyzing fluorescence spectra to characterize type and freshness of olive oils The potential of synchronous fluorescence spectroscopic measurements for the classification of olive oil samples with respect to type (extra virgin/refined) and shelf-life condition (expired/non-expired) was examined. Data multidimensionality was reduced by application of the PCA method. Six classification methods, namely, LDA, QDA, RDA, KNN, SVM, and RF, were used to analyze fluorescence data. Classification accuracy was employed to evaluate the performance of these methods for the classification of olive oil samples. The results indicate that fresh and expired olive oils produced with different methods, extra virgin (cold pressed) and refined, are characterized by different fluorescence spectra. KNN and SVM outperform the other classification methods in distinguishing olive oils. The lowest classification error rates were obtained with these two classification methods for measurements at the wavelength interval of 30 nm, and equaled 5.4, 5.7 and 2.9, 3.5% for the four and three classes’ models, respectively. Support vector machine ; Olive oil ; Pattern recognition (psychology) ; Artificial intelligence ; Chemistry ; Fluorescence ; Mathematics ; Biological system ; Food science ; Computer science ; Biology Spectroscopy and Chemometric Analyses ; Edible Oils Quality and Analysis ; Advanced Chemical Sensor Technologies
Authors: Saeid Nezamabadi | Xavier Frank | Jean‐Yves Delenne | Julien Averseng | Farhang Radjaï
Source: Computer Physics Communications (article, 2018-11-09)
Field: Materials Science — Materials Chemistry

Parallel implicit contact algorithm for soft particle systems Compressibility ; Jamming ; Particle (ecology) ; Compaction ; Materials science ; Formalism (music) ; Mechanics ; Granular material ; Deformation (meteorology) ; Statistical physics ; Computer science ; Physics ; Composite material ; Condensed matter physics ; Geology Material Dynamics and Properties ; Granular flow and fluidized beds ; Rheology and Fluid Dynamics Studies
Authors: Võ Thị Thanh Châu | Huynh Thi MinhThanh | Phạm Đình Dũ | Trần Thanh Tâm Toàn | Trần Ngọc Tuyền | Tran Xuan Mau | Đinh Quang Khiếu
Source: Journal of Chemistry (article, 2018-06-24)
Field: Chemistry — Inorganic Chemistry

Metal-Organic Framework-101 (MIL-101): Synthesis, Kinetics, Thermodynamics, and Equilibrium Isotherms of Remazol Deep Black RGB Adsorption In the present paper, the synthesis of metal-organic framework-101 (MIL-101) and Remazol Deep Black RGB (RDB) adsorption on MIL-101 were demonstrated. The kinetics of RDB adsorption on MIL-101 was studied using Weber’s intraparticle diffusion model and the pseudo-first- and pseudo-second-order kinetic models. Particularly, the statistical method of piecewise linear regression and multi-nonlinear regression was employed to analyse the adsorption data according to the previously mentioned kinetic models. The results indicated that the adsorption process followed the three-step pseudo-first-order kinetic equation, which was consistent with the results of the intraparticle diffusion model with three linear segments. This model best described the experimental data. In addition, the adsorption isotherm data were studied using five adsorption models, namely, Langmuir, Freundlich, Redlich–Peterson, Toth, and Sips in nonlinear forms, and the Langmuir model is the most appropriate for the experimental data. The values of energies of activation of adsorption were calculated, and they revealed that the adsorption process was of endothermic chemical nature. A statistical comparison using Akaike information criterion to estimate the goodness of fit of the kinetic and isotherm models was presented. Chemistry ; Adsorption ; Freundlich equation ; Akaike information criterion ; Thermodynamics ; Langmuir ; Diffusion ; Nonlinear regression ; Endothermic process ; Langmuir adsorption model ; Physical chemistry ; Regression analysis ; Mathematics ; Statistics ; Physics Metal-Organic Frameworks: Synthesis and Applications ; Adsorption and biosorption for pollutant removal ; Thermal and Kinetic Analysis
Authors: M. Mirzajanzadeh | V.S. Deshpande | N.A. Fleck
Source: Journal of the Mechanics and Physics of Solids (article, 2018-10-09)
Field: Materials Science — Materials Chemistry

Water rise in a cellulose foam: By capillary or diffusional flow? Critical experiments and predictive models reveal that water rise through a cellulose foam is initially by capillary rise, followed by non-linear diffusion in the presence of trapping sites. Classical ideas on capillary rise are supported by observations that the Washburn law is obeyed up to the Jurin height. However, water rise continues beyond the Jurin height, and this subsequent phase is diffusion-controlled according to the following evidence: the nature of the quantitative dependence of water rise upon time, the insensitivity of water rise to the direction of gravity, and the fact that the water front continues to rise in the foam after the water reservoir has been removed. Water diffusion occurs through the cellulose fibre network, along with trapping/de-trapping at molecular sites. The diffusion equations are solved numerically, and, upon comparing the predictions with the observed response, values are obtained for the diffusion constant and for the ratio of trap density to lattice density. The diffusion model explains why the drying of a damp foam is a slow process: the emptying of filled traps requires diffusion through an adjacent lattice of low water content. Capillary action ; Materials science ; Diffusion ; Mechanics ; Fick's laws of diffusion ; Cellulose ; Molecular diffusion ; Diffusion process ; Thermodynamics ; Trapping ; Composite material ; Chemistry ; Physics Pickering emulsions and particle stabilization ; Fluid Dynamics and Thin Films ; Advanced Cellulose Research Studies
Authors: Chengyun Hua | Austin J. Minnich
Source: Physical review. B./Physical review. B (article, 2018-01-10)
Field: Materials Science — Materials Chemistry

Heat dissipation in the quasiballistic regime studied using the Boltzmann equation in the spatial frequency domain Quasiballistic heat conduction, in which some phonons propagate ballistically over a thermal gradient, has recently become of intense interest. Most works report that the thermal resistance associated with nanoscale heat sources is far larger than predicted by Fourier's law; however, recent experiments show that in certain cases the difference is negligible despite the heaters being far smaller than phonon mean-free paths. In this work, we examine how thermal resistance depends on the heater geometry using analytical solutions of the Boltzmann equation. We show that the spatial frequencies of the heater pattern play the key role in setting the thermal resistance rather than any single geometric parameter, and that for many geometries the thermal resistance in the quasiballistic regime is no different than the Fourier prediction. We also demonstrate that the spectral distribution of the heat source also plays a major role in the resulting transport, unlike in the diffusion regime. Our work provides an intuitive link between the heater geometry, spectral heating distribution, and the effective thermal resistance in the quasiballistic regime, a finding that could impact strategies for thermal management in electronics and other applications. Boltzmann equation ; Dissipation ; Statistical physics ; Physics ; Boltzmann constant ; Domain (mathematical analysis) ; Heat equation ; Frequency domain ; Lattice Boltzmann methods ; Mechanics ; Quantum electrodynamics ; Mathematical analysis ; Mathematics ; Thermodynamics ; Quantum mechanics Thermal properties of materials ; Thermal Radiation and Cooling Technologies ; Optical properties and cooling technologies in crystalline materials
Authors: Ling Ding | Zhenbin Lyu | Dinesh Dhumal | Chai‐Lin Kao | Monique Bernard | Ling Peng
Source: Science China Materials (article, 2018-07-31)
Field: Materials Science — Polymers and Plastics

Dendrimer-based magnetic resonance imaging agents for brain cancer Magnetic resonance imaging ; Dendrimer ; Materials science ; Glioblastoma ; Brain tumor ; Cancer ; Molecular imaging ; Nanotechnology ; Biomedical engineering ; Medicine ; Cancer research ; Radiology ; Pathology ; Biology ; In vivo ; Internal medicine Dendrimers and Hyperbranched Polymers ; Lanthanide and Transition Metal Complexes ; Advanced biosensing and bioanalysis techniques
Authors: Penny Nymark | Pekka Kohonen | Vesa Hongisto | Roland C. Grafström
Source: Annals of the American Thoracic Society (article, 2018-04-01)
Field: Materials Science — Materials Chemistry

Toxic and Genomic Influences of Inhaled Nanomaterials as a Basis for Predicting Adverse Outcome An immense variety of different types of engineered nanomaterials are currently being developed and increasingly applied to consumer products. Importantly, engineered nanomaterials may pose unexplored adverse health effects because of their small size. Particularly in occupational settings, the dustiness of certain engineered nanomaterials involves risk of inhalation and influences on lung function. These facts call for quick and cost-effective safety testing practices, such as that obtained through multiparametric high-throughput screening using cultured human lung cells. The predictive value of such in vitro-based testing depends partly on the effectiveness of coverage of the mechanisms underlying toxicity effects. The concept of adverse outcome pathways covers the array of causative effects starting from a molecular initiating event via cellular-, organ-, individual-, and population-level effects. Screening for adverse outcome pathway-related effects that drive the eventual toxic outcome provides a good basis for developing predictive testing methods and data-driven integrated testing strategies for hazard and risk assessment. Temporal and inherited genomic changes are likely to drive many adverse responses to engineered nanomaterials, such as multiwalled carbon nanotubes, of which one specific form has recently been evaluated as possibly carcinogenic. Here, we briefly describe current state-of-the-art strategies for analyzing and understanding genomic influences of engineered nanomaterial exposure, including the selected focus on lung disease, and strategies for using mechanistic knowledge to predict and prevent adverse outcome. Medicine ; Adverse Outcome Pathway ; Adverse effect ; Outcome (game theory) ; Intensive care medicine ; Computational biology ; Internal medicine Nanoparticles: synthesis and applications ; Air Quality and Health Impacts ; Heavy Metal Exposure and Toxicity
Authors: Adam J. Williamson | Hans K. Carlson | Jennifer V. Kuehl | Leah L. Huang | Anthony T. Iavarone | Adam M. Deutschbauer | John D. Coates
Source: Frontiers in Microbiology (article, 2018-07-09)
Field: Materials Science — Biomaterials

Dissimilatory Sulfate Reduction Under High Pressure by Desulfovibrio alaskensis G20 Biosouring results from production of H<sub>2</sub>S by sulfate-reducing microorganisms (SRMs) in oil reservoirs. H<sub>2</sub>S is toxic, corrosive, and explosive, and as such, represents a significant threat to personnel, production facilities, and transportation pipelines. Since typical oil reservoir pressures can range from 10 to 50 MPa, understanding the role that pressure plays in SRM metabolism is important to improving souring containment strategies. To explore the impact of pressure, we grew an oil-field SRM isolate, <i>Desulfovibrio alaskensis</i> G20, under a range of pressures (0.1-14 MPa) at 30°C. The observed microbial growth rate was an inverse function of pressure with an associated slight reduction in sulfate and lactate consumption rate. Competitive fitness experiments with randomly bar-coded transposon mutant library sequencing (RB-TnSeq) identified several genes associated with flagellar biosynthesis and assembly that were important at high pressure. The fitness impact of specific genes was confirmed using individual transposon mutants. Confocal microscopy revealed that enhanced cell aggregation occurs at later stages of growth under pressure. We also assessed the effect of pressure on SRM inhibitor potency. Dose-response experiments showed a twofold decrease in the sensitivity of <i>D. alaskensis</i> to the antibiotic chloramphenicol at 14 MPa. Fortuitously, pressure had no significant influence on the inhibitory potency of the common souring controlling agent nitrate, or the emerging SRM inhibitors perchlorate, monofluorophosphate, or zinc pyrithione. Our findings improve the conceptual model of microbial sulfate reduction in high-pressure environments and the influence of pressure on souring inhibitor efficacy. Desulfovibrio ; Sulfate ; Sulfate-reducing bacteria ; High pressure ; Chemistry ; Reduction (mathematics) ; Environmental chemistry ; Physics ; Thermodynamics ; Mathematics ; Organic chemistry Calcium Carbonate Crystallization and Inhibition ; Metal Extraction and Bioleaching ; Minerals Flotation and Separation Techniques