jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: S. M. P. Valleti | Sergei V. Kalinin | Christopher T. Nelson | Jonathan J. P. Peters | Wen Dong | Richard Beanland | Xiaohang Zhang | Ichiro Takeuchi | Maxim Ziatdinov
Source: AIP Advances (article, 2022-10-01)
Field: Materials Science — Materials Chemistry

Unsupervised learning of ferroic variants from atomically resolved STEM images An approach for the analysis of atomically resolved scanning transmission electron microscopy data with multiple ferroic variants in the presence of imaging non-idealities and chemical variabilities based on a rotationally invariant variational autoencoder (rVAE) is presented. We show that an optimal local descriptor for the analysis is a sub-image centered at specific atomic units, since materials and microscope distortions preclude the use of an ideal lattice as a reference point. The applicability of unsupervised clustering and dimensionality reduction methods is explored and is shown to produce clusters dominated by chemical and microscope effects, with a large number of classes required to establish the presence of rotational variants. Comparatively, the rVAE allows extraction of the angle corresponding to the orientation of ferroic variants explicitly, enabling straightforward identification of the ferroic variants as regions with constant or smoothly changing latent variables and sharp orientational changes. This approach allows further exploration of the chemical variability by separating the rotational degrees of freedom via rVAE and searching for remaining variability in the system. The code used in this article is available at https://github.com/saimani5/ferroelectric_domains_rVAE. Autoencoder ; Unsupervised learning ; Cluster analysis ; Dimensionality reduction ; Curse of dimensionality ; Artificial intelligence ; Computer science ; Invariant (physics) ; Microscope ; Degrees of freedom (physics and chemistry) ; Pattern recognition (psychology) ; Physics ; Materials science ; Optics ; Artificial neural network Electronic and Structural Properties of Oxides ; Force Microscopy Techniques and Applications ; Electron and X-Ray Spectroscopy Techniques
Authors: David A. Brooks | Olivier Piétrement | Elodie Dardillac | Ayesha Jayantha | Manuel Arsenio Lores Guevara | Fidel Antonio Castro-Smirnov | Pîlar Aranda | Eduardo Ruiz‐Hitzky | Bernard S. López
Source: ACS Omega (article, 2022-12-28)
Field: Materials Science — Biomaterials

Impact of Increased Sonication-Induced Dispersion of Sepiolite on Its Interaction with Biological Macromolecules and Toxicity/Proliferation in Human Cells Sepiolite is a natural clay silicate that is widely used, including biomedical applications; notably sepiolite shows promising features for the transfer of biological macromolecules into mammalian cells. However, before its use, such an approach should address the efficiency of binding to biological macromolecules and cell toxicity. Because sepiolite spontaneously forms aggregates, its disaggregation can represent an important challenge for improving the suspension performance and the assembly with biological species. However, this can also influence the toxicity of sepiolite in mammalian cells. Here, a very pure commercial sepiolite (Pangel S9), which is present as a partially defibrillated clay mineral, is used to study the consequences of additional deagglomeration/dispersion through sonication. We analyzed the impact of extra sonication on the dispersion of sepiolite aggregates. Factors such as sonication time, sonicator power, and temperature are taken into account. With increasing sonication time, a decrease in aggregation is observed, as well as a decrease in the length of the nanofibers monitored by atomic force microscopy. Changes in the temperature and pH of the solution are also observed during the sonication process. Moreover, although the adsorption capacity of bovine serum albumin (BSA) protein on sepiolite is increased with sonication time, the DNA adsorption efficiency remains unaffected. Finally, sonication of sepiolite decreases the hemolytic activity in blood cells and the toxicity in two different human cell lines. These data show that extra sonication of deagglomerated sepiolite can further favor its interaction with some biomacromolecules (e.g., BSA), and, in parallel, decrease sepiolite toxicity in mammalian cells. Therefore, sonication represents an alluring procedure for future biomedical applications of sepiolite, even when using commercial defibrillated particles. Sonication ; Sepiolite ; Dispersion (optics) ; Chemical engineering ; Chemistry ; Adsorption ; Macromolecule ; Biophysics ; Toxicity ; Materials science ; Chromatography ; Biochemistry ; Organic chemistry ; Biology Clay minerals and soil interactions ; Therapeutic Uses of Natural Elements ; Hydrogels: synthesis, properties, applications
Authors: Meilan Ge | Yuye Wang | Junfeng Zhu | Bin Wu | Degang Xu | Jianquan Yao
Source: Sensors (article, 2022-05-27)
Field: Chemistry — Physical and Theoretical Chemistry

Low-Frequency Vibrational Spectroscopy Characteristic of Pharmaceutical Carbamazepine Co-Crystals with Nicotinamide and Saccharin The pharmaceutical co-crystal has attracted increasing interest due to the improvement of physicochemical properties of active pharmaceutical ingredients. The characterization of pharmaceutical co-crystal is an integral part of the pharmaceutical field. In this paper, the low-frequency vibrational properties for carbamazepine co-crystals with nicotinamide and saccharin (CBZ-NIC and CBZ-SAC) have been characterized by combining the THz spectroscopy with low-wavenumber Raman spectroscopy. The experiment results show that, compared with the individual constituents, CBZ-NIC and CBZ-SAC co-crystals not only have different characteristic absorption peaks in the 0.3-2.5 THz region, but also have significant low-wavenumber Raman characteristic peaks in 0-100 cm<sup>-1</sup>. Density functional theory was performed to simulate the terahertz and low-wavenumber Raman spectra of the two co-crystals, where the calculation agreed well with the measured vibrational peak positions. The vibrational modes of CBZ-NIC and CBZ-SAC co-crystals were assigned through comparing theoretical results with the experimental spectra. Meanwhile, the low-frequency infrared and/or Raman active of characteristic peaks for such co-crystals were discussed. The results indicate the combination of THz spectroscopy and low-wavenumber Raman spectroscopy can provide more comprehensive low-frequency vibrational information for pharmaceutical co-crystals, such as collective vibration and skeleton vibration, which could play an important role in pharmaceutical science. Saccharin ; Nicotinamide ; Carbamazepine ; Spectroscopy ; Chemistry ; Materials science ; Organic chemistry ; Medicine ; Physics ; Epilepsy ; Psychiatry Crystallography and molecular interactions ; Nonlinear Optical Materials Research ; Crystallization and Solubility Studies
Authors: Ramona Mhanna | Michael Giroux | Kenneth J. T. Livi | Chao Wang | Andrei Fluerasu | Lutz Wiegart | Yugang Zhang | Mark Sutton | Robert L. Leheny
Source: The Journal of Physical Chemistry C (article, 2022-02-15)
Field: Materials Science — Materials Chemistry

Extremely Slow Diffusion of Gold Nanoparticles under Confinement in Mesoporous Silica We report an X-ray photon correlation spectroscopy (XPCS) study of the mobility of colloidal gold nanoparticles with a diameter of approximately 4 nm in glycerol under confinement within the channels of SBA-15 mesoporous silica with pore diameters of approximately 6 and 12 nm. The XPCS correlation functions result from an effective heterodyne signal due to the mixing of the coherent scattering from the nanoparticles and the mesoporous silica. Over the range of wave vectors and hence length scales probed, the nanoparticle dynamics are well described by one-dimensional diffusion. The nanoparticle diffusivity varies with temperature in a manner expected based on the temperature-dependent viscosity of glycerol; however, the magnitudes of the diffusion coefficients are several orders of magnitude smaller than those of the nanoparticles in bulk glycerol. We consider mechanisms that might contribute to this reduction in diffusivity including enhancement in hydrodynamic drag under confinement, effects of nanoparticle adsorption to the pore walls, and slowing structural dynamics in glycerol due to the combination of the nanometer-scale confinement and the presence of the nanoparticles. Nanoparticle ; Materials science ; Thermal diffusivity ; Dynamic light scattering ; Mesoporous material ; Diffusion ; Mesoporous silica ; Colloidal gold ; Chemical physics ; Scattering ; Nanometre ; Chemical engineering ; Nanotechnology ; Chemistry ; Composite material ; Thermodynamics ; Optics ; Organic chemistry Material Dynamics and Properties ; Phase Equilibria and Thermodynamics ; Theoretical and Computational Physics
Authors: Sergi Vela | Maria Fumanal | Carmen Sousa
Source: Journal of Materials Chemistry C (article, 2022-12-09)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Understanding kinetically controlled spin transitions in bistable spin crossover materials Kinetic rate constants are evaluated computationally for the spin-forbidden thermal relaxations of SCO complexes, unveiling their mechanism, and retrieving accurate T LIESST predictions. Spin crossover ; Bistability ; Materials science ; Kinetic energy ; Spin (aerodynamics) ; Spin transition ; Thermal ; Condensed matter physics ; Reaction rate constant ; Chemical physics ; Thermodynamics ; Kinetics ; Physics ; Quantum mechanics ; Optoelectronics Magnetism in coordination complexes ; Lanthanide and Transition Metal Complexes ; Organic and Molecular Conductors Research
Authors: Niclas Conen | Martin Fuchs | Alexander Hoffmann | Sonja Herres‐Pawlis | Andreas Jupke
Source: Advanced Sustainable Systems (article, 2022-11-14)
Field: Materials Science — Biomaterials

Taking the Next Step—Model‐Based Analysis of Robust and Non‐Toxic Zn Catalysts for the Ring Opening Polymerization of Lactide in the Polymer Melt Abstract In the field of bioplastics, complete kinetic models are rare but needed for industrial scale‐up. Herein, a complete kinetic model is developed to describe the behavior of robust and nontoxic guanidine carboxy Zn complexes in the lab‐scale ring opening polymerization (ROP) of l ‐lactide, mimicking industrial melt polymerization in the presence of a co‐initiator. The model includes inter‐ and intramolecular transesterification and random chain scission, considering the single site activity of the studied catalyst class, based upon the “asme”‐ligand already established in lactide ROP. This allows for the description of reaction rate constants and the prediction of conversion as well as molar mass and dispersity of the obtained polymer. It is further shown that the model can be applied to describe the same characteristics for the faster, next generation catalysts based on the archetype “asme” catalyst. This lays the foundation for a faster catalyst design, targeting the needs of industry in developing fast and nontoxic alternatives for the industrially used toxic ROP catalyst Sn octanoate, bridging the gap between academia and industry. Dispersity ; Lactide ; Polymerization ; Catalysis ; Ring-opening polymerization ; Polymer ; Materials science ; Intramolecular force ; Molar mass ; Polymer chemistry ; Chemistry ; Chemical engineering ; Organic chemistry ; Engineering biodegradable polymer synthesis and properties ; Microplastics and Plastic Pollution ; Advanced Polymer Synthesis and Characterization
Authors: Zixiu Lu | Shujian Wang | Zhu Zhuo | Guo-Ling Li | Haomiao Zhu | Wei Wang | You‐Gui Huang | Maochun Hong
Source: RSC Advances (article, 2022-01-01)
Field: Materials Science — Materials Chemistry

Achieving stable photoluminescence by double thiacalix[4]arene-capping: the lanthanide-oxo cluster core matters Luminescence stability is a critical consideration for applying phosphors in practical devices. In this work, we report two categories of double <i>p-tert</i>-butylthiacalix[4]arene (H<sub>4</sub>TC4A) capped clusters that exhibit characteristic lanthanide luminescence. Specifically, {[Ln<sub>4</sub>(μ<sub>4</sub>-OH)(TC4A)<sub>2</sub>(DMF)<sub>6</sub>(CH<sub>3</sub>OH)<sub>3</sub>(HCOO)Cl<sub>2</sub>]}·<i>x</i>CH<sub>3</sub>OH (Ln = Eu (1), Tb (2); <i>x</i> = 0-1) with square-planar [Ln<sub>4</sub>(μ<sub>4</sub>-OH)] cluster cores and {[Ln<sub>9</sub>(μ<sub>5</sub>-OH)<sub>2</sub>(μ<sub>3</sub>-OH)<sub>8</sub>(OCH<sub>3</sub>) (TC4A)<sub>2</sub> (H<sub>2</sub>O)<sub>24</sub>Cl<sub>9</sub>]}·<i>x</i>DMF (Ln = Gd (3), Tb (4), Dy (5); <i>x</i> = 2-6) with hourglass-like [Ln<sub>9</sub>(μ<sub>5</sub>-OH)<sub>2</sub>(μ<sub>3</sub>-OH)<sub>8</sub>] cluster cores are synthesized and characterized. By comparing 2 and 4, we find that several critical luminescence properties (such as quantum efficiency and luminescence stabilities) depend directly on the cluster core structure. With the square-planar [Ln<sub>4</sub>(μ<sub>4</sub>-OH)] cluster cores, 2 demonstrates high quantum yield (∼65%) and excellent luminescence stability against moisture, high temperature, and UV-radiation. A white light-emitting diode (LED) with ultrahigh color quality is successfully fabricated by mixing 2 with commercial phosphors. These results imply that high quality phosphors might be achieved by exploiting the double thiacalix[4]arene-capping strategy, with an emphasis on the cluster core structure. Lanthanide ; Photoluminescence ; Cluster (spacecraft) ; Core (optical fiber) ; Chemistry ; Crystallography ; Materials science ; Computer science ; Optoelectronics ; Organic chemistry ; Ion ; Computer network ; Composite material Lanthanide and Transition Metal Complexes ; Magnetism in coordination complexes ; Nanocluster Synthesis and Applications
Authors: Andrés Carmona-Hernández | Ricardo Orozco-Cruz | Franco Carpio | Clarisa Campechano-Lira | Francisco López-Huerta | Edgar Mejía-Sánchez | A. Contreras | Ricardo Galván-Martínez
Source: Metals (article, 2022-09-19)
Field: Materials Science — Metals and Alloys

Electrochemical Noise Analysis of the X70 Pipeline Steel under Stress Conditions Using Symmetrical and Asymmetrical Electrode Systems In this work, electrochemical monitoring of stress corrosion cracking (SCC) behavior of a X70 steel in acidic synthetic soil solution during the slow strain rate test (SSRT) was performed by electrochemical noise (EN) using the conventional arrangement of symmetrical electrodes and electrochemical emission spectroscopy (EES) using the asymmetrical arrangement replacing the second working electrode for a platinum micro-cathode. The statistical method, fast Fourier transform, and discrete wavelet transform were used for analyzing the potential and current signals recorded by both arrangements. The results showed that EN arrangement was more effective to detect the crack initiation at a point close to yield strength despite stress-induced asymmetry in one of the electrodes. For the EES arrangement, the micro-cathode had a strong influence on the electrochemical noise of the current and potential under stress conditions. From the transient features, statistical parameters, and wavelet analysis, a discontinuous transgranular SCC mechanism was found. The resistance values obtained by EN measurements had better correlation with the electrochemical impedance spectroscopy results (EIS) than EES measurements. Electrochemical noise ; Materials science ; Electrode ; Dielectric spectroscopy ; Electrochemistry ; Cathode ; Stress corrosion cracking ; Noise (video) ; Stress (linguistics) ; Corrosion ; Electrical impedance ; Composite material ; Analytical Chemistry (journal) ; Chemistry ; Electrical engineering ; Engineering ; Computer science Hydrogen embrittlement and corrosion behaviors in metals ; Corrosion Behavior and Inhibition ; Non-Destructive Testing Techniques
Authors: Maciej Ulaszewski | Robert Janowski | Andrzej Janowski
Source: ELCVIA Electronic Letters on Computer Vision and Image Analysis (article, 2022-02-01)
Field: Chemistry — Analytical Chemistry

Application of computer vision to egg detection on a production line in real time. In this paper we investigate the application of computer vision to the problem of egg detection on a production line in real-time. For this purpose a dedicated software was designed and implemented that exploited the advantages of neural networks or template matching approaches. To verify the correctness of the developed software as well as to confirm its applicability to real life problems a number of carefully designed experiments have been carried out. These experiments let us reveal what approaches are best suited for supporting egg detection on a production line in real-time. Computer science ; Correctness ; Production line ; Software ; Line (geometry) ; Artificial intelligence ; Matching (statistics) ; Artificial neural network ; Real-time computing ; Production (economics) ; Computer vision ; Operating system ; Algorithm ; Engineering Spectroscopy and Chemometric Analyses
Authors: Binbin Zhang | Jiayang Yan | Weichen Xu | Yu Teng | Zhuoyuan Chen | Jizhou Duan
Source: Frontiers in Materials (article, 2022-01-26)
Field: Materials Science — Surfaces, Coatings and Films

Eco-Friendly Anticorrosion Superhydrophobic Al2O3@PDMS Coating With Salt Deliquescence Self-Coalescence Behaviors Under High Atmospheric Humidity Bio-inspired superhydrophobic coatings have been demonstrated to be promising anticorrosion materials. However, developing robust superhydrophobic coatings through simple one-step fluorine-free procedures to meet various functional requirements remains a major challenge. In this study, we fabricated an eco-friendly superhydrophobic Al 2 O 3 @PDMS composite coating with mechanical robustness based on Al 2 O 3 NPs, PDMS, and spray coating technique. To characterize surface morphologies, chemical compositions, surface wettability, and anticorrosion properties, FE-SEM, EDS, XPS, contact angle meter, electrochemical impendence spectroscopy, and potentiodynamic polarization techniques were employed. The electrochemical results show that |Z| 0.01 Hz and R ct values of the superhydrophobic Al 2 O 3 @PDMS coating were four orders of magnitude higher than bare Q235 carbon steel, indicating a significant improvement in corrosion resistance. Furthermore, the deliquescence behaviors of NaCl salt particles and the instantaneous self-coalescence phenomenon were recorded under high atmospheric humidity to suggest that a superhydrophobic surface with Cassie–Baxter interfacial contacts can serve as an efficient barrier to suppress the formation of saline liquid thin films and protect the underlying substrate from corrosion. This robust superhydrophobic Al 2 O 3 @PDMS coating is expected to be easily applied to a variety of substrates and to find potential applications for liquid repellency, self-cleaning, corrosion resistance, and other properties. Materials science ; Contact angle ; Wetting ; Coating ; Corrosion ; Superhydrophobic coating ; Chemical engineering ; Composite material ; Coalescence (physics) ; Composite number ; Nanotechnology Surface Modification and Superhydrophobicity ; Advanced Sensor and Energy Harvesting Materials ; Adhesion, Friction, and Surface Interactions
Authors: Robert J. Meier
Source: AppliedChem (article, 2022-11-11)
Field: Chemistry — Organic Chemistry

Group Contribution Revisited: The Enthalpy of Formation of Organic Compounds with “Chemical Accuracy” Part III Group contribution (GC) methods to predict thermochemical properties are eminently important to process design. We report on a GC parametrization for the heat of formation of organic molecules exhibiting chemical accuracy, i.e., a maximum 1 kcal/mol (4.2 kJ/mol) difference between experimental and model values, whilst having a minimum number of parameters to avoid overfitting. We report an extension of recent findings to chloro-alkanes, fluoro-hydrocarbons, benzylhalides, nitro-alkanes, and acetals. Compared to the existing literature, we obtained a superior model exhibiting chemical accuracy, with exceptions when the inherent GC assumption on linearity and additivity is not valid. Moreover, to have a reliable method and not only a low absolute average deviation as reported in most publications, we accepted no or exceptionally few outliers. The example of the 1,3-dioxolane acetals revealed that by adopting the appropriate size of a group representing the acetal leads to a model showing good accuracy. The overall conclusion of the three papers on this topic is that it is feasible to achieve chemical accuracy when using high-quality experimental data and the judicious definition of chemical groups. Despite the GC method being old, the present work shows substantial and necessary increase in performance can still be achieved. Overfitting ; Additive function ; Acetal ; Chemistry ; Standard enthalpy of formation ; Enthalpy ; Outlier ; Parametrization (atmospheric modeling) ; Thermodynamics ; Group (periodic table) ; Group contribution method ; Computational chemistry ; Mathematics ; Organic chemistry ; Statistics ; Computer science ; Phase (matter) ; Physics ; Phase equilibrium Chemical Thermodynamics and Molecular Structure ; Phase Equilibria and Thermodynamics ; Thermal and Kinetic Analysis
Authors: Leah Granger | Muh-Jang Chen | Donald W. Brenner | M.A. Zikry
Source: Metals (article, 2022-11-26)
Field: Materials Science — Materials Chemistry

The Challenges of Modeling Defect Behavior and Plasticity across Spatial and Temporal Scales: A Case Study of Metal Bilayer Impact Atomistic molecular dynamics (MD) and a microstructural dislocation density-based crystalline plasticity (DCP) framework were used together across time scales varying from picoseconds to nanoseconds and length scales spanning from angstroms to micrometers to model a buried copper–nickel interface subjected to high strain rates. The nucleation and evolution of defects, such as dislocations and stacking faults, as well as large inelastic strain accumulations and wave-induced stress reflections were physically represented in both approaches. Both methods showed similar qualitative behavior, such as defects originating along the impactor edges, a dominance of Shockley partial dislocations, and non-continuous dislocation distributions across the buried interface. The favorable comparison between methods justifies assumptions used in both, to model phenomena, such as the nucleation and interactions of single defects and partials with reflected tensile waves, based on MD predictions, which are consistent with the evolution of perfect and partial dislocation densities as predicted by DCP. This substantiates how the nanoscale as modeled by MD is representative of microstructural behavior as modeled by DCP. Materials science ; Nucleation ; Plasticity ; Dislocation ; Partial dislocations ; Molecular dynamics ; Condensed matter physics ; Nanoscopic scale ; Mesoscopic physics ; Bilayer ; Chemical physics ; Nanotechnology ; Physics ; Composite material ; Chemistry ; Thermodynamics Microstructure and mechanical properties ; High-Velocity Impact and Material Behavior ; Metal and Thin Film Mechanics