jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Claudio Zeni | Kevin Rossi | Aldo Glielmo | Francesca Baletto
Source: Advances in Physics X (article, 2019-01-01)
Field: Materials Science — Materials Chemistry

On machine learning force fields for metallic nanoparticles Machine learning algorithms have recently emerged as a tool to generate force fields which display accuracies approaching the ones of the ab-initio calculations they are trained on, but are much faster to compute. The enhanced computational speed of machine learning force fields results key for modelling metallic nanoparticles, as their fluxionality and multi-funneled energy landscape needs to be sampled over long time scales. In this review, we first formally introduce the most commonly used machine learning algorithms for force field generation, briefly outlining their structure and properties. We then address the core issue of training database selection, reporting methodologies both already used and yet unused in literature. We finally report and discuss the recent literature regarding machine learning force fields to sample the energy landscape and study the catalytic activity of metallic nanoparticles. Force field (fiction) ; Artificial intelligence ; Machine learning ; Field (mathematics) ; Computer science ; Energy landscape ; Core (optical fiber) ; Nanoparticle ; Nanotechnology ; Materials science ; Physics ; Mathematics Machine Learning in Materials Science ; Computational Drug Discovery Methods ; nanoparticles nucleation surface interactions
Authors: K. Sugiyama | Yosuke Sumiya | Makito Takagi | Kenichiro Saita | Satoshi Maeda
Source: Physical Chemistry Chemical Physics (article, 2019-01-01)
Field: Materials Science — Materials Chemistry

Understanding CO oxidation on the Pt(111) surface based on a reaction route network Analysis of a reaction on a solid surface is an important task for understanding the catalytic reaction mechanism. In this study, we studied CO oxidation on the Pt(111) surface by using the artificial force induced reaction (AFIR) method. A systematic reaction path search was done, and the reaction route network was created. This network included not only bond rearrangement paths but also migration paths of adsorbed species. Then, the obtained network was analyzed using a kinetics method called rate constant matrix contraction (RCMC). It is found that the bottleneck of the overall reaction is the CO2 generation step from an adsorbed CO molecule and an O atom. This result is consistent with the Langmuir-Hinshelwood (LH) mechanism with O2 dissociation discussed in previous studies. The present procedure, i.e., construction of the reaction route network by the AFIR method followed by application of the RCMC kinetics method to the resultant reaction route network, was fully systematic and uncovered two aspects: the impact of the existence of multiple paths in each bond rearrangement step and an entropic contribution arising from short-range migration of adsorbed species. Chemistry ; Catalysis ; Reaction rate constant ; Elementary reaction ; Reaction mechanism ; Dissociation (chemistry) ; Adsorption ; Reaction rate ; Kinetics ; Physical chemistry ; Organic chemistry ; Physics Catalytic Processes in Materials Science ; Machine Learning in Materials Science ; Catalysis and Oxidation Reactions
Authors: Djafar Chabane | Mohammad Ibrahim | Fabien Harel | Abdesslem Djerdir | Denis Candusso | O. Elkedim
Source: International Journal of Hydrogen Energy (article, 2019-09-23)
Field: Materials Science — Materials Chemistry

Energy management of a thermally coupled fuel cell system and metal hydride tank Hydride ; Proton exchange membrane fuel cell ; Hydrogen storage ; Hydrogen ; Hydrogen fuel ; Materials science ; Exothermic reaction ; Energy carrier ; Exothermic process ; Chemical engineering ; Energy storage ; Intermetallic ; Chemistry ; Fuel cells ; Thermodynamics ; Metallurgy ; Power (physics) ; Organic chemistry ; Engineering ; Alloy Hydrogen Storage and Materials ; Fuel Cells and Related Materials ; Electrocatalysts for Energy Conversion
Authors: Georges Limbert | Marc Masen | Damien Pond | Helen K. Graham | Michael J. Sherratt | Rikeen D. Jobanputra | Andrew McBride
Source: Biotribology (article, 2019-03-01)
Field: Materials Science — Polymers and Plastics

Biotribology of the ageing skin—Why we should care Ageing ; Parallels ; Globe ; Population ageing ; Health care ; Interface (matter) ; Perspective (graphical) ; Population ; Skin care ; Function (biology) ; Medicine ; Healthy ageing ; Human body ; Gerontology ; Psychology ; Neuroscience ; Environmental health ; Biology ; Computer science ; Economic growth ; Evolutionary biology ; Engineering ; Mechanical engineering ; Anatomy ; Nursing ; Economics Textile materials and evaluations ; Advanced Sensor and Energy Harvesting Materials ; Sports Performance and Training
Authors: Xiangru Chen | Qijie Zhai | Dong Han | Bao-Hua Dai | Hardy Mohrbacher
Source: Advances in Manufacturing (article, 2019-12-10)
Field: Materials Science — Materials Chemistry

Molybdenum alloying in cast iron and steel Abstract Metal casting is an important manufacturing technology for efficiently producing massive components with complex shape. A large share of industrial castings is made from iron and steel alloys, combining attractive properties and low production cost. Upgrading of properties in cast iron and steel is mainly achieved by alloying and in fewer cases by heat treatment. Molybdenum is an important alloying element in that respect, increasing strength, hardness and toughness. It also facilitates particular heat treatments such as austempering. The paper describes the metallurgical functionality of molybdenum alloying in iron-based castings and demonstrates its effectiveness for applications in the automotive and mining industry. Metallurgy ; Materials science ; Molybdenum ; Cast iron ; Automotive industry ; Casting ; Toughness ; Austempering ; Microstructure ; Austenite ; Engineering ; Bainite Metal Alloys Wear and Properties ; Aluminum Alloy Microstructure Properties ; Microstructure and Mechanical Properties of Steels
Authors: Takeshi Kawasaki | Kang Kim
Source: Scientific Reports (article, 2019-05-31)
Field: Materials Science — Materials Chemistry

Spurious violation of the Stokes–Einstein–Debye relation in supercooled water The theories of Brownian motion, the Debye rotational diffusion model, and hydrodynamics together provide us with the Stokes-Einstein-Debye (SED) relation between the rotational relaxation time of the [Formula: see text]-th degree Legendre polynomials [Formula: see text], and viscosity divided by temperature, η/T. Experiments on supercooled liquids are frequently performed to measure the SED relations, [Formula: see text]k<sub>B</sub>T/η and D<sub>t</sub>[Formula: see text], where D<sub>t</sub> is the translational diffusion constant. However, the SED relations break down, and its molecular origin remains elusive. Here, we assess the validity of the SED relations in TIP4P/2005 supercooled water using molecular dynamics simulations. Specifically, we demonstrate that the higher-order [Formula: see text] values exhibit a temperature dependence similar to that of η/T, whereas the lowest-order [Formula: see text] values are decoupled with η/T, but are coupled with the translational diffusion constant D<sub>t</sub>. We reveal that the SED relations are so spurious that they significantly depend on the degree of Legendre polynomials. Physics ; Algorithm ; Mathematics Material Dynamics and Properties ; Phase Equilibria and Thermodynamics ; Spectroscopy and Quantum Chemical Studies
Authors: Nouh Aarab | Mohamed Laabd | Habiba Eljazouli | Rajae Lakhmiri | Hassan Kabli | Abdallah Albourine
Source: International Journal of Industrial Chemistry (article, 2019-06-29)
Field: Materials Science — Polymers and Plastics

Experimental and DFT studies of the removal of pharmaceutical metronidazole from water using polypyrrole The polypyrrole (PPy) was used as an adsorbent material for efficient removal of pharmaceutical metronidazole from aqueous solutions. The physiochemical parameters influencing the adsorption process such as adsorbent dose, temperature, pH, initial concentration and contact time were systematically investigated. The optimum adsorption efficiency is achieved at pH 6.17 after 120 min of contact time. In addition, the Langmuir isotherm and pseudo-second-order models were found to explain the metronidazole adsorption process on the PPy. The thermodynamic parameters indicate that the adsorption of metronidazole on the PPy is a spontaneous and exothermic process. The quantum calculations using density functional theory (DFT) was used to confirm the adsorption mechanism of metronidazole on the PPy. The obtained results of the interaction energy indicate that the adsorption was a physical process. The metronidazole was adsorbed by its oxygen atoms on the amine groups of PPy. Finally, the PPy polymer can be used as an efficient adsorbent for removal of pharmaceutical pollutants from wastewater. Adsorption ; Polypyrrole ; Aqueous solution ; Metronidazole ; Exothermic process ; Langmuir adsorption model ; Chemistry ; Langmuir ; Exothermic reaction ; Density functional theory ; Chemical engineering ; Polymer ; Materials science ; Inorganic chemistry ; Organic chemistry ; Polymerization ; Computational chemistry Conducting polymers and applications ; Covalent Organic Framework Applications ; Adsorption and biosorption for pollutant removal
Authors: Fei Ding | Sergey I. Bozhevolnyi
Source: IEEE Journal of Selected Topics in Quantum Electronics (review, 2019-01-22)
Field: Materials Science — Electronic, Optical and Magnetic Materials

A Review of Unidirectional Surface Plasmon Polariton Metacouplers Efficient and unidirectional excitation of surface plasmon polaritons (SPPs) and their low-frequency counterparts (i.e., spoof SPPs) is highly desired in the research area of photonics and plasmonics, while being at the same time rather challenging. Recent progress in gradient metasurfaces, ultrathin, and planar materials composed of sub-wavelength unit cells, has opened up new possibilities for efficiently coupling of free-space propagating waves to surface waves. In this paper, we will discuss the recent achievements in gradient metasurface-based unidirectional SPP couplers (i.e., metacouplers). Starting with explaining the basic concept of generalized Snell's law, we then introduce some typical examples of unidirectional SPP metacouplers, followed by an overview of polarization-controlled tunable SPP metacouplers. We also describe metacouplers that also feature other functionalities, beyond the unidirectional SPP excitation. The review is concluded with a short summary and perspective for future developments. Surface plasmon polariton ; Plasmon ; Excitation ; Polariton ; Polarization (electrochemistry) ; Planar ; Photonics ; Surface plasmon ; Optics ; Optoelectronics ; Wavelength ; Physics ; Coupling (piping) ; Materials science ; Computer science ; Chemistry Metamaterials and Metasurfaces Applications ; Plasmonic and Surface Plasmon Research ; Orbital Angular Momentum in Optics
Authors: Junlin Lu | Hao Ran | Jien Li | Jing Wan | Congcong Wang | Peiyuan Ji | Xue Wang | Guanlin Liu | Chenguo Hu
Source: Electrochimica Acta (article, 2019-12-03)
Field: Materials Science — Electronic, Optical and Magnetic Materials

A fast composite-hydroxide-mediated approach for synthesis of 2D-LiCoO2 for high performance asymmetric supercapacitor Supercapacitor ; Capacitance ; Composite number ; Materials science ; Hydroxide ; Power density ; Electrode ; Current density ; Chemical engineering ; Nanotechnology ; Electrochemistry ; Optoelectronics ; Composite material ; Power (physics) ; Chemistry ; Physics Supercapacitor Materials and Fabrication ; Advancements in Battery Materials ; MXene and MAX Phase Materials
Authors: Diletta Giuntini | Elisa Torresani | Kyle Chan | Malte Blankenburg | Lucien Saviot | Büsra Bor | Berta Domènech | Meir H. Shachar | Martin Müller | Eugene A. Olevsky | Javier E. Garay | Gerold A. Schneider
Source: Nanoscale Advances (article, 2019-01-01)
Field: Materials Science — Materials Chemistry

Iron oxide-based nanostructured ceramics with tailored magnetic and mechanical properties: development of mechanically robust, bulk superparamagnetic materials Nanostructured iron-oxide based materials with tailored mechanical and magnetic behavior are produced in bulk form. By applying ultra-fast heating routines <i>via</i> spark plasma sintering (SPS) to supercrystalline pellets, materials with an enhanced combination of elastic modulus, hardness and saturation magnetization are achieved. Supercrystallinity - namely the arrangement of the constituent nanoparticles into periodic structures - is achieved through self-assembly of the organically-functionalized iron oxide nanoparticles. The optimization of the following SPS regime allows the control of organics' removal, necking, iron oxide phase transformations and nano-grain size retention, and thus the fine-tuning of both mechanical properties and magnetic response, up until the production of bulk mm-size superparamagnetic materials. Materials science ; Ceramic ; Superparamagnetism ; Iron oxide ; Nanotechnology ; Composite material ; Oxide ; Metallurgy ; Magnetization ; Magnetic field Magnetic Properties and Synthesis of Ferrites ; Magnesium Oxide Properties and Applications ; Aluminum Alloys Composites Properties
Authors: Durga Prasad Hari | Lionel Schouwey | Verity Barber | Rosario Scopelliti | Farzaneh Fadaei‐Tirani | Jérôme Waser
Source: Chemistry - A European Journal (article, 2019-04-08)
Field: Chemistry — Organic Chemistry

Ethynylbenziodazolones (EBZ) as Electrophilic Alkynylation Reagents for the Highly Enantioselective Copper‐Catalyzed Oxyalkynylation of Diazo Compounds Ethynylbenziodoxol(on)e (EBX) cyclic hypervalent iodine reagents are now established reagents for the alkynylation of radicals and nucleophiles, yet they present limited possibilities for further structure and reactivity modification. Herein, the first synthesis is reported for the corresponding ethynylbenziodazolone (EBZ) reagents, in which the oxygen atom in the iodoheterocycle is replaced by a nitrogen atom. The substituent on the nitrogen enables further fine-tuning of the reagent structure and reactivity. EBZ reagents are obtained easily from the corresponding benzamides by using a one-step procedure, and display reactivity comparable to that of EBX reagents. In particular, they are applied in an asymmetric copper-catalyzed oxyalkynylation of diazo compounds, which proceeds in high yield and enantioselectivity for a broad range of substituents on the diazo compounds and the alkyne. Diazo ; Hypervalent molecule ; Chemistry ; Reagent ; Enantioselective synthesis ; Reactivity (psychology) ; Electrophile ; Nucleophile ; Combinatorial chemistry ; Alkyne ; Organic chemistry ; Catalysis ; Substituent Cyclopropane Reaction Mechanisms ; Catalytic C–H Functionalization Methods ; Oxidative Organic Chemistry Reactions
Authors: Nagendra S. Chauhan | Sivaiah Bathula | Bhasker Gahtori | Yury V. Kolen’ko | Ajay Dhar
Source: Journal of Electronic Materials (article, 2019-08-05)
Field: Materials Science — Materials Chemistry

Enhanced Thermoelectric Performance in Hf-Free p-Type (Ti, Zr)CoSb Half-Heusler Alloys Materials science ; Spark plasma sintering ; Thermoelectric effect ; Dopant ; Phonon scattering ; Doping ; Thermoelectric materials ; Solid solution ; Acceptor ; Thermal conductivity ; Analytical Chemistry (journal) ; Optoelectronics ; Metallurgy ; Sintering ; Condensed matter physics ; Composite material ; Thermodynamics ; Chemistry Advanced Thermoelectric Materials and Devices ; Heusler alloys: electronic and magnetic properties ; Chalcogenide Semiconductor Thin Films
Authors: Gervasio Zaldívar | Sridhar Vemulapalli | Venkatareddy Udumula | Martin Conda‐Sheridan | Mario Tagliazucchi
Source: The Journal of Physical Chemistry C (article, 2019-06-24)
Field: Materials Science — Biomaterials

Self-Assembled Nanostructures of Peptide Amphiphiles: Charge Regulation by Size Regulation Self-assembled nanostructures of peptide amphiphiles (PAs) with molecular structures C16K2 and C16K3 (where C indicates the number of carbon atoms in the alkyl chain and K is the lysine in the head group) were studied by a combination of theoretical modeling, transmission electron and atomic force microscopes, and acid–base titration experiments. The supramolecular morphology of the PAs (micelles, fibers, or lamellas) was dependent on the pH and ionic strength of the solution. Theoretical modeling was performed using a molecular theory that allows determining the equilibrium morphology, the size, and the charge of the soft nanoassemblies as a function of the molecular structure of the PA, and the pH and salt concentration of the solution. Theoretical predictions showed good agreement with experimental data for the pH-dependent morphology and size of the nanoassemblies and their apparent pKa’s. Two interesting effects associated with charge regulation mechanisms were found: first, ionic strength plays a dual role in the modulation of the electrostatic interactions in the system, which leads to complex dependencies of the aggregation numbers with salt concentration; second, the aggregation number of the nanostructures decreases upon increasing the charge per PA. The second mechanism, charge regulation by size regulation, tunes the net charge of the assemblies to decrease the electrostatic repulsions. A remarkable consequence of this behavior is that adding an extra lysine residue to the charged region of the PAs can lead to an unexpected decrease in the total charge of the micelles. Micelle ; Ionic strength ; Chemical physics ; Nanostructure ; Ionic bonding ; Supramolecular chemistry ; Chemistry ; Static electricity ; Electrostatics ; Alkyl ; Amphiphile ; Self-assembly ; Transmission electron microscopy ; Molecular dynamics ; Crystallography ; Nanotechnology ; Ion ; Materials science ; Copolymer ; Computational chemistry ; Physical chemistry ; Organic chemistry ; Aqueous solution ; Crystal structure ; Physics ; Polymer Supramolecular Self-Assembly in Materials ; Polydiacetylene-based materials and applications ; Lipid Membrane Structure and Behavior
Authors: Fuyang Huo | Hua Zhang | Zhuo Chen | Ling Qiu | Jialei Liu | Shuhui Bo | I.V. Kityk
Source: Journal of Materials Science Materials in Electronics (article, 2019-05-30)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Novel nonlinear optical push–pull fluorene dyes chromophore as promising materials for telecommunications Abstract Two principally novel chromophores A, B based on fluorene electron donor were synthesized and explored by 1 H NMR, 13 C NMR, and MS spectra. The delocalized energy levels have been estimated by UV–Vis absorption spectra. The principal innovation consists in modification by addition of amino group. The titled materials have demonstrated a high solubility in common organic solvents, good compatibility with polymers. The maximally achieved electro-optic efficiency of the poled film possessing 25 wt% of A doped in PMMA (25 wt% A/PMMA) achieved a value of 18 pm/V at wavelength 1310 nm, and 25 wt% B/PMMA possessed an electrooptical coefficient equal to 43 pm/V. This one open a perspective of their direct application in optoelectronic telecommunication devices for laser light modulation. Chromophore ; Fluorene ; Delocalized electron ; Materials science ; Absorption spectroscopy ; Optoelectronics ; Photochemistry ; Solubility ; Wavelength ; Proton NMR ; Polymer ; Chemistry ; Optics ; Physical chemistry ; Organic chemistry ; Physics Nonlinear Optical Materials Research ; Nonlinear Optical Materials Studies ; Porphyrin and Phthalocyanine Chemistry
Authors: Yu‐Chen Wei | Zhiyun Zhang | Yi‐An Chen | Chih‐I Wu | Zong‐Ying Liu | Ssu‐Yu Ho | Jiun‐Chi Liu | Jia‐An Lin | Pi‐Tai Chou
Source: Communications Chemistry (article, 2019-01-28)
Field: Chemistry — Physical and Theoretical Chemistry

Mechanochromism induced through the interplay between excimer reaction and excited state intramolecular proton transfer Abstract Excited-state intramolecular proton transfer (ESIPT) and excimer formation are unimolecular and bimolecular reactions, respectively. The coupling between these two reactions has been rarely observed. Here we show the interplay between ESIPT and excimer formation in CF 3 -HTTH (2,2′-(thiazolo[5,4-d]thiazole-2,5-diyl)bis(4-(trifluoromethyl)phenol) solid crystal, resulting in the extensively broad multiple emissions spanning from 420 to 750 nm. Comprehensive structural, time-resolved spectroscopic, and two-photon microscopic studies of CF 3 -HTTH in crystal lattice unveil the pre-equilibrium ESIPT between the normal (N*) and tautomer (T*) form, for which the slow population decay and well-ordered lattice packing facilitate excimeric (E*) formation, rendering N* (460 nm), T* (520 nm) and E* (600 nm) triple emissions. In contrast, the lower degree of packing on the solid surface prohibits excimer formation, showing only the ESIPT process. The correlation between luminescence properties and packing structure sheds light on the corresponding mechanochromic effect based on molecular solid architecture and provide new insight into the aggregation-induced properties. Excimer ; Intramolecular force ; Excited state ; Photochemistry ; Tautomer ; Aggregation-induced emission ; Crystal structure ; Chemistry ; Luminescence ; Proton ; Materials science ; Crystallography ; Fluorescence ; Stereochemistry ; Atomic physics ; Optoelectronics ; Optics Photochemistry and Electron Transfer Studies ; Luminescence and Fluorescent Materials ; Organic Light-Emitting Diodes Research
Authors: Jennifer L. Wierman | Olivier Paré-Labrosse | Antoine Sarracini | Jessica E. Besaw | Michael J. Cook | Saeed Oghbaey | Hazem Daoud | P. Mehrabi | I.A. Kriksunov | Anling Kuo | David J. Schuller | Scott Smith | Oliver P. Ernst | Doletha M. E. Szebenyi | Sol M. Grüner | R. J. Dwayne Miller | Aaron D. Finke
Source: IUCrJ (article, 2019-02-22)
Field: Materials Science — Materials Chemistry

Fixed-target serial oscillation crystallography at room temperature A fixed-target approach to high-throughput room-temperature serial synchrotron crystallography with oscillation is described. Patterned silicon chips with microwells provide high crystal-loading density with an extremely high hit rate. The microfocus, undulator-fed beamline at CHESS, which has compound refractive optics and a fast-framing detector, was built and optimized for this experiment. The high-throughput oscillation method described here collects 1-5° of data per crystal at room temperature with fast (10° s<sup>-1</sup>) oscillation rates and translation times, giving a crystal-data collection rate of 2.5 Hz. Partial datasets collected by the oscillation method at a storage-ring source provide more complete data per crystal than still images, dramatically lowering the total number of crystals needed for a complete dataset suitable for structure solution and refinement - up to two orders of magnitude fewer being required. Thus, this method is particularly well suited to instances where crystal quantities are low. It is demonstrated, through comparison of first and last oscillation images of two systems, that dose and the effects of radiation damage can be minimized through fast rotation and low angular sweeps for each crystal. Oscillation (cell signaling) ; Undulator ; Synchrotron radiation ; Femtosecond ; Crystal (programming language) ; Synchrotron ; Beamline ; Detector ; Materials science ; Optics ; Diffraction ; Physics ; Laser ; Computer science ; Chemistry Enzyme Structure and Function ; Advanced X-ray Imaging Techniques ; Biochemical and Molecular Research