jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Georgia Bradshaw | Mel O’Leary | Arthur S. F. Purser | Balder Villagomez‐Bernabe | Cyrus Wyett | F. J. Currell | Marcus Webb
Source: Scientific Reports (article, 2023-08-28)
Field: Chemistry — Inorganic Chemistry

A new approach for simulating inhomogeneous chemical kinetics In this paper, inhomogeneous chemical kinetics are simulated by describing the concentrations of interacting chemical species by a linear expansion of basis functions in such a manner that the coupled reaction and diffusion processes are propagated through time efficiently by tailor-made numerical methods. The approach is illustrated through modelling [Formula: see text]- and [Formula: see text]-radiolysis in thin layers of water and at their solid interfaces from the start of the chemical phase until equilibrium was established. The method's efficiency is such that hundreds of such systems can be modelled in a few hours using a single core of a typical laptop, allowing the investigation of the effects of the underlying parameter space. Illustrative calculations showing the effects of changing dose-rate and water-layer thickness are presented. Other simulations are presented which show the approach's capability to solve problems with spherical symmetry (an approximation to an isolated radiolytic spur), where the hollowing out of an initial Gaussian distribution is observed, in line with previous calculations. These illustrative simulations show the generality and the computational efficiency of this approach to solving reaction-diffusion problems. Furthermore, these example simulations illustrate the method's suitability for simulating solid-fluid interfaces, which have received a lot of experimental attention in contrast to the lack of computational studies. Radiolysis ; Diffusion ; Computer science ; Statistical physics ; Gaussian ; Generality ; Chemical reaction ; Chemical kinetics ; Series (stratigraphy) ; Thermodynamics ; Applied mathematics ; Physics ; Chemistry ; Kinetics ; Mathematics ; Physical chemistry ; Computational chemistry ; Classical mechanics Radioactive element chemistry and processing ; Nuclear reactor physics and engineering ; Radioactive contamination and transfer
Authors: Sarabpreet Singh | Mahdi Ghafariasl | Hsin-Yu Ko | Sampath Gamage | Robert A. DiStasio | Michael Snure | Yohannes Abate
Source: arXiv (Cornell University) (preprint, 2023-06-30)
Field: Materials Science — Materials Chemistry

Substrate Induced van der Waals Force Effect on the Stability of Violet Phosphorous The van der Waals (vdWs) forces between monolayers has been a unique distinguishing feature of exfoliable materials since the first isolation of graphene. However, the vdWs interaction of exfoliable materials with their substrates and how this interface force influences their interaction with the environment is yet to be well understood.Here, we experimentally and theoretically unravel the role of vdWs forces between the recently rediscovered wide band gap p-type vdW semiconductor violet phosphorus (VP), with various substrates (including, SiO$_2$, mica, Si, Au) and quantify how VP stability in air and its interaction with its surroundings is influenced by the interface force.Using a combination of infrared nanoimaging and theoretical modeling we find the vdWs force at the interface to be a main factor that influences how VP interacts with its surroundings.In addition, the hydrophobicity of the substrate and the substrate surface roughness modify the vdWs force there by influencing VP stability. Our results could guide in the selection of substrates when vdW materials are prepared and more generally highlight the key role of interface force effects that could significantly alter physical properties of vdWs materials. van der Waals force ; Monolayer ; Substrate (aquarium) ; Chemical physics ; Force spectroscopy ; Graphene ; Mica ; Materials science ; Nanotechnology ; Semiconductor ; Chemistry ; Optoelectronics ; Atomic force microscopy ; Composite material ; Molecule Graphene research and applications ; 2D Materials and Applications ; Molecular Junctions and Nanostructures
Authors: Min‐Ho Kim | Haeseong Jang | Eunryeol Lee | Jaehyun Park | Tae-Won Kim | Jeongwoo Seo | Young Hwa Jung | Seok Ju Kang | Jaephil Cho | Min Gyu Kim | Dong‐Hwa Seo | Hyun‐Wook Lee
Source: Research Square (preprint, 2023-02-03)
Field: Materials Science — Polymers and Plastics

Metal-to-metal charge transfer driven by the electropositive species for stable anionic redox chemistry Metal ; Redox ; Chemistry ; Inorganic chemistry ; Charge (physics) ; Organic chemistry ; Physics Conducting polymers and applications ; Electrochemical Analysis and Applications ; Electrocatalysts for Energy Conversion
Authors: Sian Xie | Brais Martínez‐López | Pascale Chalier | Benjamin Saulnier | Narendra Reddy | Yves Grohens | François Touchaleaume
Source: Journal of Applied Polymer Science (article, 2023-06-30)
Field: Materials Science — Biomaterials

Polycaprolactone—Eugenol systems: Interactions, retention and diffusion of the bioactive compound Abstract The retention ability of polycaprolactone (PCL) films and their potential use for applications that require controlled release, were evaluated using eugenol, an aroma compound as a model active substance. The PCL‐eugenol samples were prepared by means of a low‐temperature extrusion process that resulted in minimum losses of eugenol and a final proportion close to nominal content. The release kinetics of eugenol were monitored for different conditions of temperature and relative humidity, both by an usual gas chromatography analysis but also by spectroscopy method that revealed sufficient. The release kinetics were compared to the numerical results obtained by the resolution of Fickian and a power‐law models. Results showed that the temperature had an influence on the release rate, and that the release kinetics were mostly Fickian. Moreover, the determination of the Arrhenius parameters will allow the use of the Fickian model to dimension PCL samples for other applications requiring controlled release. Eugenol ; Polycaprolactone ; Diffusion ; Fick's laws of diffusion ; Kinetics ; Arrhenius equation ; Materials science ; Chemical engineering ; Analytical Chemistry (journal) ; Controlled release ; Chemistry ; Chromatography ; Activation energy ; Thermodynamics ; Polymer ; Composite material ; Nanotechnology ; Organic chemistry biodegradable polymer synthesis and properties ; Nanocomposite Films for Food Packaging ; Polymer Science and PVC
Authors: Craff Emeline
Source: SPIRE - Sciences Po Institutional REpository (preprint, 2023-03-20)
Field: Chemistry — Inorganic Chemistry

Interactions des espèces issues de la radiolyse du milieu eau/NaOH pH ≈ 9 avec le Np (+V) : Spéciation et Hydrolyse Neptunium (Np) is one of the minor actinides present in the spent fuel from nuclearpower plants. Np is the main species and considered as an ultimate waste, which, in the future, will be stored in a deep geological repository. However, to reduce uncertainties on the reliability of the project, particularly the possibility of infiltration of water into the waste package, further investigations are required. Presence of radionuclides inside the package leads to radiolysis phenomenon, inducing the production of radicals and molecular species. Water and these new formed species can interact with actinides and thus change their chemical behavior (speciation, hydrolysis, complexation…). In this context, the goal of the researches described in this report is to studyfundamentally the impact of radiation (α and γ) on the Np chemistry, especially in alkali medium. First of all, the elaboration of a protocol to prepare Np solutions was developped in order to obtain only one species in solution. The study of water/NaOH pH ≈ 9 solutions radiolysis allowed to determine radiolytic formation yields of H2 and H2O2 for each type of radiation. Comparison of these yields with those obtained with the presence of Np led to deduce redox mechanisms involved in the system. Thus, at low doses (<10 kGy), Np (+V) is reduced to Np (+IV), then the irradiation is continued (> 10 kGy), Np(+IV) is oxidized to Np (+V). The characterization of these Np species by UV-VIS-Nir, XANES and EXAFS allowed to better understand the role of radiolysis on Np speciation in the conditions of nuclear waste storage. Radiolysis ; Genetic algorithm ; Hydrolysis ; Chemistry ; Inorganic chemistry ; Environmental chemistry ; Nuclear chemistry ; Organic chemistry ; Aqueous solution ; Ecology ; Biology Radioactive element chemistry and processing ; Radioactive contamination and transfer
Authors: Colin R. Crick | Vinicíus Diniz | Joseph C. Bear | Susanne Rath
Source: Research Square (preprint, 2023-10-09)
Field: Materials Science — Polymers and Plastics

Porous sulfur polymers for effective aqueous-phase organic contaminant removal – a low-cost sustainable material Abstract Emerging contaminants in supposably potable water supplies are a global and growing concern. Maintaining conventional water treatment approaches to tackle growing contamination levels would mean exponentially increasing treatment costs, with some contaminants circumventing these efforts altogether. New approaches for water treatment are therefore required. Sulfur polymers made by “inverse vulcanization” are a highly promising candidate material for this purpose. In this work, porous sulfur polymers (PSPs) were synthesized from elemental sulfur and 1,3-diisopropenylbenzene, with porosity introduced via salt templating. The result is a material that can strongly absorb and chemically neutralize a model contaminant (caffeine). PSPs show adsorption up to 5 times higher than a leading adsorption material (activated carbon). This is the first-ever report demonstrating sulfur polymers as effective materials for removing emerging contaminants from water. The versatile synthesis of sulfur polymers offers variation, which means that there is much more to explore in this exciting research area. Sulfur ; Adsorption ; Polymer ; Contamination ; Porosity ; Water treatment ; Porous medium ; Materials science ; Chemical engineering ; Environmental chemistry ; Waste management ; Environmental science ; Chemistry ; Environmental engineering ; Organic chemistry ; Composite material ; Metallurgy ; Engineering Synthesis and properties of polymers ; Flame retardant materials and properties ; Tribology and Wear Analysis
Authors: Hasan Özcan
Source: Ömer Halisdemir Üniversitesi Mühendislik Bilimleri Dergisi (article, 2023-10-03)
Field: Materials Science — Materials Chemistry

Modeling of carbon dioxide electrolysis with reversible fuel cells In this study use of a reversible solid oxide fuel cell for co-electrolysis of steam and carbon dioxide is investigated using zero and multi-dimensional modeling tools. A zero-dimensional model is taken into account as the base model and applied to a single-cell system. Dimensions of the cell is used for the zero-dimensional model to provide a base for the multi-dimensional performance enhancement of the cell with micro to macro scales. An optimal current density is available which is slightly lower than 1000 A/m2 to provide low overpotentials and higher efficiency. Maximum reachable cell efficiency in this case is about 75%. Electrolysis ; Carbon dioxide ; Materials science ; Fuel cells ; Solid oxide fuel cell ; Oxide ; Zero (linguistics) ; Base (topology) ; Carbon fibers ; Chemical engineering ; Chemistry ; Nuclear engineering ; Mathematics ; Engineering ; Metallurgy ; Electrode ; Anode ; Composite material ; Physical chemistry ; Mathematical analysis Advancements in Solid Oxide Fuel Cells ; Supercapacitor Materials and Fabrication ; Fuel Cells and Related Materials
Authors: Alf Honigmann | Daxiao Sun | Xueping Zhao | Tina Wiegand | Giacomo Bartolucci | Cécilie Martin-Lemaitre | Stephan W. Grill | Anthony A. Hyman | Christoph A. Weber
Source: Research Square (preprint, 2023-09-29)
Field: Materials Science — Materials Chemistry

Assembly of tight junction belts by surface condensation and actin elongation Abstract Tight junctions play an essential role in sealing tissues, by forming belts of adhesion strands around cellular perimeters. The formation of a tight junction occurs into two steps, initiation at cell-cell contacts, and elongation around the perimeter. Recent work has shown that nucleation is governed by condensation of scaffold proteins. However, the mechanisms by which condensates are spatially controlled to initiate at cell-cell contacts and elongate around cell perimeters remain unknown. Here, we combined cell biology, molecular reconstitution and thermodynamic modelling to show that belt formation is driven by a surface phase transition coupled to actin polymerization. Adhesion receptor oligomerization provides the signal for local surface condensation of ZO proteins. Surface condensates directly facilitate actin polymerization and filament bundling, which drives elongation of receptor-ZO-actin condensates into a junctional belt. We conclude that surface phase transitions provide a robust mechanism to locally control the position and shape of protein condensates. Elongation ; Condensation ; Tight junction ; Surface (topology) ; Chemistry ; Biophysics ; Cell biology ; Materials science ; Composite material ; Geometry ; Physics ; Biology ; Mathematics ; Meteorology ; Ultimate tensile strength Anodic Oxide Films and Nanostructures ; Nanoporous metals and alloys ; Corrosion Behavior and Inhibition
Authors: Virginie Marry | Sébastien Le Crom | Eric Ferrage | Laurent J. Michot | B. Farago | Alfred Delville | Emmanuelle Dubois
Source: ChemRxiv (preprint, 2023-10-24)
Field: Materials Science — Biomaterials

Role of cationic organisation on water dynamics in saponite clays Water dynamics impacts many phenomena from geosciences to biology, especiallly in confined environments. In the presence of charged interfaces, there are some ions the role of which with regards to the water dynamics is unclear. Here a synthetic saponite clay, which is oriented in a film, is used as confining medium in the bilayer state. It confines two water layers between negatively charged planes, the charge of which is compensated by sodium cations. Water dynamics is determined both parallel and perpendicular to the charged clay layers with Neutron Spin Echo (NSE). This technique gives access to long enough times and directly provides the intermediate scattering function that is calculated on the other hand by Molecular Dynamics (MD) simulations. These latter also enable the study of cations dynamics, not experimentally accessible on this time scale. The results point towards a huge role of these cations on the water dynamics, mainly through their local structure and localization between the charged confining planes. Saponite ; Bilayer ; Chemical physics ; Molecular dynamics ; Dynamics (music) ; Scattering ; Neutron scattering ; Materials science ; Clay minerals ; Chemistry ; Physics ; Mineralogy ; Membrane ; Optics ; Computational chemistry Clay minerals and soil interactions ; Soil and Unsaturated Flow ; NMR spectroscopy and applications
Authors: Gorav Gorav | Vrushali Khedekar | P. Nandakumar | Geetha K. Varier
Source: bioRxiv (Cold Spring Harbor Laboratory) (preprint, 2023-09-29)
Field: Materials Science — Materials Chemistry

Role of charge in enhanced nuclear transport and retention of graphene quantum dots Abstract The nuclear pore complexes on the nuclear membrane function as the sole gateway of molecular communication between the nucleus and the cytoplasm regulating the transport of molecules, including nucleic acids and proteins. The present study seeks to undertake a comprehensive investigation of the kinetics of transport of negatively charged graphene quantum dots through nuclear membranes and quantify their nuclear transport characteristics and translocation rates. Experiments are carried out in permeabilized HeLa cells using time-lapse confocal fluorescence microscopy. Introducing negative charge onto biomolecular probes leads to electrostatic interaction with the nuclear pore complexes resulting in significant changes in their nuclear translocation rates. We find that the negatively charged graphene quantum dots are transported to the nuclei at a fast rate and two distinct transport pathways are involved in the translocation. Furthermore, complementary experiments on the nuclear import and export of these graphene quantum dots confirm the bidirectionality of transport with similar translocation rates. Our studies also show that negatively charged graphene quantum dots exhibit good retention properties revealing their potential as excellent drug carriers. Statement of significance The nuclear pore complexes control the bidirectional transport of biomolecules between the nucleus and cytoplasm. The noteworthy behaviors exhibited by negatively charged graphene quantum dots with respect to the nuclear uptake show their potential utility not only as drug carriers but also as facilitators for the retention of drugs within the nucleus. The fast import of carriers helps to achieve faster drug delivery, and the retention ensures the passing of the drug to daughter nuclei. Graphical abstract Quantum dot ; Nuclear transport ; Graphene ; Biophysics ; Nuclear pore ; Cytoplasm ; Nucleus ; Chromosomal translocation ; Chemistry ; Nanotechnology ; Cell nucleus ; Chemical physics ; Materials science ; Cell biology ; Biochemistry ; Biology Graphene research and applications ; Advanced biosensing and bioanalysis techniques ; Graphene and Nanomaterials Applications
Authors: P. Ramakrishnan | Abanti Sahoo
Source: Chemical and Process Engineering New Frontiers (article, 2023-04-11)
Field: Materials Science — Materials Chemistry

A study on mass transfer modelling in SOFC anode: Comparison of diffusion mass transfer models for estimation of diffusion overpotential The mathematical approach to SOFC modelling helps to reduce dependence on the experimental approach. In the current study, six different diffusion mass transfer models were compared to more accurately predict the process behavior of fuel and product diffusion for SOFC anode. The prediction accuracy of the models was extensively studied over a range of parameters. New models were included as compared to previous studies. The Knudsen diffusion phenomenon was considered in all the models. The stoichiometric flux ratio approach was used. All the models were validated against experimental data for a binary (CO-CO2) and a ternary fuel system (H2-15 H2O-Ar). For ternary system, the pressure gradient is important for pore radius below 0.6 μm and current density above 0.5 A/cm2. For binary system, the pressure gradient may be ignored. The analysis indicates that the MBFM is identified to be the best performing and versatile model under critical SOFC operating conditions such as fuel composition and cell temperature. The diffusive slip phenomenon included in MBFM is useful in SOFC operating conditions when fuel contains heavy molecules. The DGMFM is a good approximation of DGM for the binary system. Mass transfer ; Overpotential ; Diffusion ; Anode ; Materials science ; Thermodynamics ; Chemistry ; Chromatography ; Electrochemistry ; Physics ; Electrode ; Physical chemistry Advancements in Solid Oxide Fuel Cells ; Electronic and Structural Properties of Oxides ; Fuel Cells and Related Materials
Authors: Sedigheh Khanmohammadi Khoshui | Seyed Abdolkarim Hosseini Ravandi | Mohammad Karimi | Zahra Talebi
Source: Journal of Applied Polymer Science (article, 2023-09-02)
Field: Materials Science — Biomaterials

Robust water‐stable poly (ethersulfone)/poly (ethyleneimine) nanofibrous membranes for nitrate adsorption Abstract Nanofibrous media or electrospun webs are widely used as affinity membranes due to their extraordinary properties. In this study, the micro‐nano structure PES/PEI membrane was fabricated by electrospinning. The stability of the membrane during adsorption and washing is very important for affinity membranes. The fabricated web was insolubilized through an optimized crosslinking reaction by glutaraldehyde. Effect of crosslinking time and concentration on adsorption efficiency of adsorbent for nitrate studied using batch experiments. The morphology of the nanofibrous web before and after crosslinking was characterized by scanning electron microscopy (SEM). Fourier transform infrared spectroscopy was used for studying the change in functional groups of PES/PEI composite. Results show that 90 min of crosslinking reaction by immersion method in 0.71% glutaraldehyde in water/acetone medium could successfully insolubilize the polyethyleneimine and change the smooth surface of the nanofibrous web to a rough state with nano spherules. The kinetics studies show that nitrate adsorption by PES/PEI composite follows a pseudo‐second‐order kinetic model. The adsorption isotherm was also investigated using Langmuir and Freundlich models. Results show that the adsorption of nitrate on PES/PEI follows the Langmuir model with a maximum adsorption capacity of 53.47 mg/g which is considered a high value comparing other studies. Adsorption ; Glutaraldehyde ; Membrane ; Chemical engineering ; Materials science ; Freundlich equation ; Electrospinning ; Langmuir adsorption model ; Scanning electron microscope ; Fourier transform infrared spectroscopy ; Langmuir ; Polymer chemistry ; Nuclear chemistry ; Chemistry ; Chromatography ; Composite material ; Organic chemistry ; Polymer Electrospun Nanofibers in Biomedical Applications ; Advanced Sensor and Energy Harvesting Materials ; Membrane Separation Technologies
Authors: Tina Sabel
Source: Research Square (preprint, 2023-03-08)
Field: Materials Science — Surfaces, Coatings and Films

The interplay of processing-related influences on the formation of volume holographic gratings in a free- surface epoxy-based recording material Abstract Understanding the formation processes of holographic gratings in polymers as a function of material composition and processing is important for the development of new materials for holography and associated applications. Among the processing-related factors that affect grating formation in volume holographic recording material, pre-exposure, pre-baking, and dark storage, as well as the associated variations in layer thickness and composition, are usually underestimated. This study highlights the influence and interaction of these factors and shows that they should not be neglected. This is of particular importance for samples with a free surface. Here, one such epoxy-based free-surface material is investigated. To determine the influence of pre-baking on the holographic grating formation as well as on the achieved refractive index contrast, angular resolved analysis of volume holographic phase gratings is applied through point-by-point scanning of the local material response. Grating characteristics are determined by comparison with simulations based the rigorous coupled wave theory. Thus, the optimal dose for pre-baking can be determined, as well as the optimal exposure time, depending on this dose. The influence of dark storage on the material response is investigated over a period of 12 weeks and shows a strong dependence on the deposited energy density. Holography ; Grating ; Materials science ; Diffraction efficiency ; Holographic grating ; Refractive index ; Optics ; Epoxy ; Volume (thermodynamics) ; Polymer ; Optoelectronics ; Diffraction grating ; Composite material ; Physics ; Thermodynamics Optical Coatings and Gratings ; Photorefractive and Nonlinear Optics ; Photonic and Optical Devices