jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Javier E. Sánchez-Galán | Fatima Rangel Barranco | Jorge Serrano Reyes | Evelyn Itzel Quirós-McIntire | José Ulises Jiménez | José Fábrega
Source: Advances in Science Technology and Engineering Systems Journal (article, 2021-03-01)
Field: Chemistry — Analytical Chemistry

Using Supervised Classification Methods for the Analysis of Multi-spectral Signatures of Rice Varieties in Panama In this article supervised classification methods for the analysis of local Panamanian rice crops using Near-Infrared (NIR) spectral signatures are assessed. Neural network (Multilayer Perceptron-MLP) and Tree based (Decision Trees-DT and Random Forest-RF) algorithms are used as regression and supervised classification of the spectral signatures by rice varieties, against other crops and by plant phenology (days after planting). Also, satellite derived spectral signature is validated with a field collected spectral model. Results suggest that MLP networks, either for regression or classification, were more efficient (RMSE of 8.78 and 0.068, respectively) than either tree based methods to regress/classify the rice spectral signature (RMSE of 19.37, 19.09 and 0.979, respectively). The validation made using satellite derived spectral signatures resulted in MLP models with RMSE of 0.216 and 7.318, respectively, leaving room for further improvement of the models. This work aimed to present a practical example of the employment of recent supervised classification algorithms for the determination of regression and classification models from reflectance spectral signatures in local rice varieties. Panama ; Spectral analysis ; Artificial intelligence ; Pattern recognition (psychology) ; Mathematics ; Computer science ; Statistics ; Physics Spectroscopy and Chemometric Analyses ; Rice Cultivation and Yield Improvement ; Agricultural Economics and Practices
Authors: Kaustubh Venkatraman | Meriem Ben Haj Slama | Vincent Taupin | Nabila Maloufi | Antoine Guitton
Source: Modelling and Simulation in Materials Science and Engineering (article, 2021-05-06)
Field: Materials Science — Materials Chemistry

Tuning critical resolved shear stress ratios for bcc-titanium Ti21S via an automated data analysis approach Abstract We introduce a novel method for automated slip trace detection and analysis based on the Hough transform algorithm and apply it to electron channeling contrast imaging micrographs. This is further augmented with an automation procedure for the determination of slip-trace crystallography in conjunction with orientation data acquired via electron backscattered diffraction. Automation is required for faster indexation of the slip traces and for more reliable statistical studies. The automation procedure was applied to different regions of interest on a β -Ti21S sample loaded in situ in tension. β -Ti21S is a bcc alloy with 48 slip systems available to accommodate plastic deformation, including all complexities associated with pencil glide. Multiple regions of interest were analyzed using the automation procedure. The acquired slip distribution statistics reveals that the majority of the slip traces belong to the {112} and {123} slip families. The deformation response of the observed regions of interest was also simulated using a full-field crystal plasticity model implemented in DAMASK, based on a phenomenological power law based constitutive formulation, incorporating all potentially active 48 slip systems. The slip system activity distribution from modelling is compared with the slip distribution statistics observed experimentally. The plasticity parameters for β -Ti21S were taken from the literature and the critically resolved shear stress (CRSS) values were adjusted to match the experimentally observed yield stress value. We begin with uniform CRSS ratios for all three potential slip system families and tune the CRSS ratios to match the slip-distribution statistics experimentally, keeping the average CRSS value the same for all cases. Thus, a method has been introduced to tune average CRSS values and ratios by considering both the macroscopic stress–strain response and the locally observed slip-distribution statistics, obtained via automated slip trace detection procedure. Critical resolved shear stress ; Slip (aerodynamics) ; Slip line field ; Materials science ; Plasticity ; Mechanics ; Shear (geology) ; Geometry ; Composite material ; Shear rate ; Mathematics ; Physics ; Thermodynamics Titanium Alloys Microstructure and Properties ; Microstructure and mechanical properties ; Advanced Electron Microscopy Techniques and Applications
Authors: Sorin Vasile Savu | Daniela Tarniţă | Gabriel Constantin Benga | Ilie Dumitru | Iulian Ştefan | Nicolae Crăciunoiu | Adrian Bebe Olei | Ionel Dănuţ Savu
Source: Energies (article, 2021-10-18)
Field: Chemistry — Organic Chemistry

Microwave Technology Using Low Energy Concentrated Beam for Processing of Solid Waste Materials from Rapana thomasiana Seashells The solid waste of Rapana thomasiana seashells both from domestic activities and natural waste on seashore can be used to obtain viable products for medical applications. However, conventional technologies applied for sintering the materials require massive energy consumption due to the resistance heating. Microwave heating represents an advanced technology for sintering, but the stability of the process, in terms of thermal runaway and microwave plasma arc discharge, jeopardizes the quality of the sintered products. This paper aims to present the results of research focused on viable heating technology and the mechanical properties of the final products. A comparative analysis, in terms of energy efficiency vs. mechanical properties, has been performed for three different heating technologies: direct microwave heating, hybrid microwave heating and resistance heating. The results obtained concluded that the hybrid microwave heating led to final products from Rapana thomasiana solid waste with similar mechanical properties compared with resistance heating. In terms of energy efficiency, the hybrid microwave heating was 20 times better than resistance heating. Microwave ; Microwave heating ; Materials science ; Process engineering ; Waste management ; Sintering ; Thermal runaway ; Environmental science ; Metallurgy ; Engineering Synthesis of Tetrazole Derivatives ; Microwave-Assisted Synthesis and Applications ; Nanomaterials for catalytic reactions
Authors: C. Albrecht | Anil Kumar | Shuozhi Xu | Abigail Hunter | Irene J. Beyerlein
Source: Physical Review Materials (article, 2021-04-06)
Field: Materials Science — Materials Chemistry

Asymmetric equilibrium core structures of pyramidal-II <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mo>〈</mml:mo><mml:mi>c</mml:mi><mml:mo>+</mml:mo><mml:mi>a</mml:mi><mml:mo>〉</mml:mo></mml:mrow></mml:math> dislocations in ten hexagonal-close-packed metals The structures of pyramidal-II $\ensuremath{\langle}c+a\ensuremath{\rangle}$ dislocations, one of the most important defects in structural hexagonal-close-packed (HCP) metals, have not been fully characterized for many of the HCP metals in use today. Here, we employ ab initio informed phase-field dislocation dynamics to determine the minimum energy structure of pyramidal $\left\{\overline{1}\overline{1}22\right\}\ensuremath{\langle}11\overline{2}3\ensuremath{\rangle}$ dislocations in ten HCP metals, including Be, Co, Mg, Re, Ti, Zn, Cd, Hf, Y, and Zr. As input for the simulations, we calculate, using first-principles density functional theory, the $\left\{\overline{1}\overline{1}22\right\}$ generalized stacking fault energy (GSFE) curves for all ten metals. From these calculations, it is found that magnetism in Co is necessary for achieving a local minimum in the GSFE curve. We observe in simulations that edge and screw character dislocations split into two partials separated by a low-energy intrinsic stacking fault. The splitting distance is shown to scale inversely with the local minimum energy normalized by the product of its shear modulus and Burgers vector. Interestingly, some HCP metals exhibit an asymmetric structure, with either unequal partial Burgers vectors or widths, in contrast to the symmetric configuration expected from linear elastic dislocation theory. We explain these structures by properties of the local maxima in their GSFE curves. Metals with larger degrees of elastic anisotropy result in dislocations with larger splitting distances than would be expected under the commonly used assumption of elastic isotropy. These findings on the sizes and asymmetry in the structures of pyramidal-II $\ensuremath{\langle}c+a\ensuremath{\rangle}$ dislocations are fundamental to understanding how these dislocations glide and interact or react with other defects when these metals are mechanically strained. Burgers vector ; Materials science ; Stacking-fault energy ; Dislocation ; Stacking fault ; Crystallography ; Condensed matter physics ; Density functional theory ; Partial dislocations ; Energy (signal processing) ; Ab initio ; Magnetism ; Physics ; Quantum mechanics ; Chemistry Microstructure and mechanical properties ; Magnesium Alloys: Properties and Applications ; Aluminum Alloy Microstructure Properties
Authors: Yuliang Chen | Changlong Hu | Liyan Xie | Xiaoyu Zhou | Bowen Li | Hui Ren | Liang Li | Guobin Zhang | Jun Jiang | Chongwen Zou
Source: Communications Materials (article, 2021-03-25)
Field: Materials Science — Polymers and Plastics

Spatially-resolved insulator-metal transition for rewritable optical gratings Abstract Optical relief gratings are usually composed of physical grooves with a constant periodicity, and typically suffer from light scattering, are mechanically fragile and are single function. Here, we develop WO 3 -based gratings by using a recently reported electron-proton synergistic doping route under ambient conditions. This doping strategy is compatible with conventional ultraviolet photolithography, and we show that it induces a selective insulator-metal phase transition and coloration in WO 3 , with spatial-resolution up to micron-scale. Due to the electrochromic-induced-contrast, a WO 3 volume phase grating without grooves and a WO 3 relief grating with tunable periodicity are demonstrated. Both gratings can be rewritten after a reset procedure by annealing in air. Our experiments demonstrate WO 3 –based gratings and an attractive technique for rewritable oxides. Materials science ; Grating ; Optoelectronics ; Photolithography ; Annealing (glass) ; Optics ; Electrochromism ; Doping ; Diffraction grating ; Electrode ; Chemistry Transition Metal Oxide Nanomaterials ; Photorefractive and Nonlinear Optics ; Optical Coatings and Gratings
Authors: Pedram Nasr | Hannah Leung | France‐Isabelle Auzanneau | Michael A. Rogers
Source: Gels (article, 2021-04-14)
Field: Materials Science — Biomaterials

Supramolecular Fractal Growth of Self-Assembled Fibrillar Networks Complex morphologies, as is the case in self-assembled fibrillar networks (SAFiNs) of 1,3:2,4-Dibenzylidene sorbitol (DBS), are often characterized by their Fractal dimension and not Euclidean. Self-similarity presents for DBS-polyethylene glycol (PEG) SAFiNs in the Cayley Tree branching pattern, similar box-counting fractal dimensions across length scales, and fractals derived from the Avrami model. Irrespective of the crystallization temperature, fractal values corresponded to limited diffusion aggregation and not ballistic particle-cluster aggregation. Additionally, the fractal dimension of the SAFiN was affected more by changes in solvent viscosity (e.g., PEG200 compared to PEG600) than crystallization temperature. Most surprising was the evidence of Cayley branching not only for the radial fibers within the spherulitic but also on the fiber surfaces. Branching (polymer chemistry) ; Materials science ; Fractal dimension ; Fractal ; Crystallization ; Diffusion-limited aggregation ; Chemical physics ; Polyethylene glycol ; Self-assembly ; Supramolecular chemistry ; Crystallography ; Chemical engineering ; Thermodynamics ; Nanotechnology ; Mathematics ; Composite material ; Chemistry ; Physics ; Crystal structure Supramolecular Self-Assembly in Materials ; Polymer composites and self-healing ; Surfactants and Colloidal Systems
Authors: Mary Alice Cusentino | Mitchell Wood | Aidan P. Thompson
Source: Nuclear Fusion (article, 2021-03-23)
Field: Materials Science — Materials Chemistry

Beryllium-driven structural evolution at the divertor surface Abstract Erosion of the beryllium first wall material in tokamak reactors has been shown to result in transport and deposition on the tungsten divertor. Experimental studies of beryllium implantation in tungsten indicate that mixed W–Be intermetallic deposits can form, which have lower melting temperatures than tungsten and can trap tritium at higher rates. To better understand the formation and growth rate of these intermetallics, cumulative molecular dynamics (MD) simulations of both high and low energy beryllium deposition in tungsten were performed. In both cases, a W–Be mixed material layer (MML) emerged at the surface within several nanoseconds, either through energetic implantation or a thermally-activated exchange mechanism, respectively. While some ordering of the material into intermetallics occurred, fully ordered structures did not emerge from the deposition simulations. Targeted MD simulations of the MML to further study the rate of Be diffusion and intermetallic growth rates indicate that for both cases, the gradual re-structuring of the material into an ordered intermetallic layer is beyond accessible MD time scales(⩽1 μ s). However, the rapid formation of the MML within nanoseconds indicates that beryllium deposition can influence other plasma species interactions at the surface and begin to alter the tungsten material properties. Therefore, beryllium deposition on the divertor surface, even in small amounts, is likely to cause significant changes in plasma-surface interactions and will need to be considered in future studies. Beryllium ; Tungsten ; Divertor ; Intermetallic ; Materials science ; Deposition (geology) ; Metallurgy ; Tokamak ; Plasma ; Nuclear physics ; Physics ; Alloy ; Geology Fusion materials and technologies ; Nuclear Materials and Properties ; Ion-surface interactions and analysis
Authors: Stephen Opoku Oppong | Frimpong Twum | James Ben Hayfron-Acquah | Yaw Marfo Missah
Source: Journal of Computer Science (review, 2021-12-01)
Field: Chemistry — Analytical Chemistry

Medicinal Plant Identification using Gabor Filters and Deep Learning Techniques: A Paper Review Computer-aided identification of plants is a branch of machine learning that has become more recognized recently and proves itself as a vital tool in numerous sectors including pharmacological science, forestry and agriculture. This has essentially generated a zeal in creating automated systems for the identification of diverse species of plants. This study reviewed plant species classification relying on leaf textural features using Gabor filters and revealed that Gabor filters perform better when combined with other feature extraction methods. Therefore, this study proposes using Log-Gabor filter in the field of plant identification to improve accuracy since they overcome the drawbacks of Gabor filters which are; the maximum bandwidth of a Gabor filter is limited to approximately one octave and Gabor filters are not optimal if one is seeking broad spectral information with maximal spatial localization. Gabor filter ; Computer science ; Artificial intelligence ; Identification (biology) ; Gabor wavelet ; Pattern recognition (psychology) ; Feature extraction ; Plant identification ; Feature (linguistics) ; Filter (signal processing) ; Gabor transform ; Field (mathematics) ; Computer vision ; Mathematics ; Time–frequency analysis Spectroscopy and Chemometric Analyses ; Smart Agriculture and AI ; Biometric Identification and Security
Authors: Tao Wang | Robert L. Sacci | Jiyuan Liang | Chi‐Linh Do‐Thanh | Juntian Fan | Hao Chen | Yifan Sun | Bishnu P. Thapaliya | Shannon M. Mahurin | Musen Zhou | Jian Wu | Scott W. Donne | Sheng Dai
Source: Journal of The Electrochemical Society (article, 2021-06-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Mechanistic Insights of Pore Contributions in Carbon Supercapacitors by Modified Step Potential Electrochemical Spectroscopy Porous carbons are widely used as electrode materials for electrical double layer (EDL)-type supercapacitors. Differentiation of capacitance contributions from micropores and mesopores is important to understand porous carbon capacitive behavior. However, this remains challenging to accomplish. Here, we present an improved step potential electrochemical spectroscopy method to investigate the contributions to capacitance from hierarchical pores and redox processes. Supercapacitor ; Capacitance ; Electrochemistry ; Mesoporous material ; Materials science ; Carbon fibers ; Capacitive sensing ; Electrode ; Nanotechnology ; Porosity ; Chemical engineering ; Dielectric spectroscopy ; Redox ; Chemistry ; Composite material ; Organic chemistry ; Physical chemistry ; Computer science Supercapacitor Materials and Fabrication ; Conducting polymers and applications ; Electrochemical sensors and biosensors
Authors: Weige Luo | Zheng Zeng | Liang Bian
Source: Minerals (article, 2021-12-12)
Field: Materials Science — Biomaterials

Effect of Lattice Substitution on Adsorption of Hexavalent Chromium by Montmorillonite, Nontronite, and Beidellite This work aims to evaluate the effect of lattice substitution on adsorption of hexavalent chromium by three kinds of typical clay minerals, and its common isomorph via experiments and calculations were performed based on density functional theory. The experiments (25 °C, 4 h, pH = 4 and without stirring) confirmed an order of adsorption capacity as follows: Montmorillonite (12 mg/g) &gt; Nontronite (9 mg/g) &gt; Beidellite (8 mg/g). Accordingly, the Mulliken populations, density of states, and band structures of the mineral models with the structural Al, Mg, Fe(II), Fe(III), and Al (in tetrahedrons) on behalf of five species of isomorph were calculated. The calculation results explain the differences between hexavalent chromium adsorption capacity of five kinds of isomorph by means of atom, key populations, overlapping valence electron orbitals, and the variation of energy band. However, no overlapping orbitals were observed in the adsorption system with structural Mg. It is implied that the structural Mg has little influence of hexavalent chromium adsorption. In conclusion, our study contributes to achieving a better understanding of modified clay minerals materials applications. Nontronite ; Hexavalent chromium ; Adsorption ; Mulliken population analysis ; Density functional theory ; Valence (chemistry) ; Clay minerals ; Materials science ; Chromium ; Inorganic chemistry ; Chemistry ; Crystallography ; Physical chemistry ; Computational chemistry ; Mineralogy ; Organic chemistry ; Metallurgy Clay minerals and soil interactions ; Adsorption and biosorption for pollutant removal ; Iron oxide chemistry and applications
Authors: Jelena Lubura | Predrag Kojić | Jelena Pavličević | Bojana Ikonić | Radovan Omorjan | Oskar Bera
Source: Hemijska industrija (article, 2021-01-01)
Field: Chemistry — Analytical Chemistry

Prediction of rubber vulcanization using an artificial neural network Determination of rubber rheological properties is indispensable in order to conduct efficient vulcanization process in rubber industry. The main goal of this study was development of an advanced artificial neural network (ANN) for quick and accurate vulcanization data prediction of commercially available rubber gum for tire production. The ANN was developed by using the platform for large-scale machine learning TensorFlow with the Sequential Keras-Dense layer model, in a Python framework. The ANN was trained and validated on previously determined experimental data of torque on time at five different temperatures, in the range from 140 to 180 oC, with a step of 10 oC. The activation functions, ReLU, Sigmoid and Softplus, were used to minimize error, where the ANN model with Softplus showed the most accurate predictions. Numbers of neurons and layers were varied, where the ANN with two layers and 20 neurons in each layer showed the most valid results. The proposed ANN was trained at temperatures of 140, 160 and 180 oC and used to predict the torque dependence on time for two test temperatures (150 and 170 oC). The obtained solutions were confirmed as accurate predictions, showing the mean absolute percentage error (MAPE) and mean squared error (MSE) values were less than 1.99 % and 0.032 dN2 m2, respectively. Vulcanization ; Mean absolute percentage error ; Artificial neural network ; Mean squared error ; Sigmoid function ; Natural rubber ; Biological system ; Approximation error ; Materials science ; Rheology ; Computer science ; Mathematics ; Composite material ; Artificial intelligence ; Algorithm ; Statistics Spectroscopy and Chemometric Analyses ; Infrastructure Maintenance and Monitoring
Authors: Masaki Takahashi | Nozomu Ito | Naoki Haruta | Hayato Ninagawa | Kohei Yazaki | Yoshihisa Sei | Tohru Sato | Makoto Obata
Source: Communications Chemistry (article, 2021-12-02)
Field: Materials Science — Materials Chemistry

Environment-sensitive emission of anionic hydrogen-bonded urea-derivative–acetate-ion complexes and their aggregation-induced emission enhancement Abstract Anions often quench fluorescence (FL). However, strong ionic hydrogen bonding between fluorescent dyes and anion molecules has the potential to control the electronic state of FL dyes, creating new functions via non-covalent interactions. Here, we propose an approach, utilising ionic hydrogen bonding between urea groups and anions, to control the electronic states of fluorophores and develop an aggregation-induced emission enhancement (AIEE) system. The AIEE ionic hydrogen-bonded complex (IHBC) formed between 1,8-diphenylnaphthalene ( p -2Urea), with aryl urea groups at the para-positions on the peri-phenyl rings, and acetate ions exhibits high environmental sensitivities in solution phases, and the FL quantum yield (QY) in ion-pair assemblies of the IHBC and tetrabutylammonium cations is more than five times higher than that of the IHBC in solution. Our versatile and simple approach for the design of AIEE dye facilitates the future development of environment-sensitive probes and solid-state emitting materials. Hydrogen bond ; Ionic bonding ; Chemistry ; Fluorescence ; Quantum yield ; Photochemistry ; Molecule ; Ion ; Urea ; Covalent bond ; Inorganic chemistry ; Organic chemistry Luminescence and Fluorescent Materials ; Molecular Sensors and Ion Detection ; Organic Light-Emitting Diodes Research