jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Bhanjan Debnath | Badri Narayanan Narasimhan | Stephanie I. Fraley | Padmini Rangamani
Source: arXiv (Cornell University) (preprint, 2024-08-11)
Field: Materials Science — Biomaterials

Modeling collagen fibril degradation as a function of matrix microarchitecture Collagenolytic degradation is a process fundamental to tissue remodeling. The microarchitecture of collagen fibril networks changes during development, aging, and disease. Such changes to microarchitecture are often accompanied by changes in matrix degradability. In vitro, collagen matrices of the same concentration but different microarchitectures also vary in degradation rate. How do different microarchitectures affect matrix degradation? To answer this question, we developed a computational model of collagen degradation. We first developed a lattice model that describes collagen degradation at the scale of a single fibril. We then extended this model to investigate the role of microarchitecture using Brownian dynamics simulation of enzymes in a multi-fibril three dimensional matrix to predict its degradability. Our simulations predict that the distribution of enzymes around the fibrils is non-uniform and depends on the microarchitecture of the matrix. This non-uniformity in enzyme distribution can lead to different extents of degradability for matrices of different microarchitectures. Our model predictions were tested using in vitro experiments with synthesized collagen gels of different microarchitectures. Experiments showed that indeed degradation of collagen depends on the matrix architecture and fibril thickness. In summary, our study shows that the microarchitecture of the collagen matrix is an important determinant of its degradability. Fibril ; Collagen fibril ; Matrix (chemical analysis) ; Degradation (telecommunications) ; Microarchitecture ; Function (biology) ; Biophysics ; Chemistry ; Materials science ; Computer science ; Composite material ; Cell biology ; Parallel computing ; Biology Collagen: Extraction and Characterization ; Orthopaedic implants and arthroplasty ; Manufacturing Process and Optimization
Authors: Zengcheng Liu | Zhongchao Wang | Yanfei Wang
Source: Research Square (preprint, 2024-03-14)
Field: Chemistry — Inorganic Chemistry

Preparation of phosphinimide and their adsorption of uranium in aqueous solution <title>Abstract</title> The phosphinimide materials described in this paper were synthesized by polymerization precipitation. The properties of complexes coordinated with metal ions can be used as adsorbents for the adsorption of radioactive elements by using ligands such as imide and phosphorus groups. Then, the synthetic phosphinimide was characterized in detail by FT-IR, SEM, EDS and XPS, and its morphology and structural changes were studied. In addition, the effects of the material on the removal of uranium(VI) from aqueous solutions at different pH, sorbent doses, contact times, initial concentrations, and temperatures were studied. The experimental data show that the adsorption process can fit the second-order kinetic model well, which is in line with the Langmuir isotherm model. The thermodynamic study of adsorption shows that the adsorption process is a spontaneous endothermic process. In addition, at a temperature of 303.15 K and pH = 6, the maximum adsorption of uranium (VI) by phosphinimide in 25 minutes can reach 276.2 mg⋅g<sup>− 1</sup>. Uranium ; Adsorption ; Aqueous solution ; Chemistry ; Nuclear chemistry ; Materials science ; Organic chemistry ; Metallurgy Radioactive element chemistry and processing ; Chemical Synthesis and Characterization ; Extraction and Separation Processes
Authors: A. Modwi | Mohamed Ali Ben Aissa | Rafia Bakheit | Abbas Ishak Alakhras | Hajo Idriss
Source: Oriental Journal Of Chemistry (article, 2024-10-31)
Field: Materials Science — Materials Chemistry

Green Fabrication of SnO2 Nanoparticles and Uses as a Powerful Sorbent for Malachite Green Detoxification Malachite green (MG) is a poisonous and carcinogenic dye that poses serious health hazards, even at low levels, necessitating its removal from aquatic ecosystems. This study examines the use of SnO₂ nanoparticles as an adsorbent to remove MG from aquatic systems and investigates the effects of contact time, pH, and initial dye concentration on adsorption efficiency. The SnO₂ nanoparticles were synthesized employing an eco-friendly approach and characterized using various techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDS), and Brunauer-Emmett-Teller (BET). The results indicate that SnO₂ nanoparticles have a high adsorption capacity for MG, reaching up to 724 mg/g with fast kinetics. The adsorption process followed the Freundlich isotherm model (R² = 0.987), indicating a heterogeneous adsorption mechanism. However, the kinetic data correlated well with the pseudo-second-order model (R² = 0.999), supporting chemisorption as the dominant process. This work shows the efficiency of SnO₂ nanoparticles as a nanosorbent for MG removal, making it a feasible option for environmental cleaning. Green chemistry ; Malachite green ; Detoxification (alternative medicine) ; Industrial chemistry ; Elsevier Biobase ; Material chemistry ; Sorbent ; Chemistry ; Nanoparticle ; Phytochemistry ; Nanotechnology ; Fabrication ; Theoretical chemistry ; Environmental chemistry ; Chemical engineering ; Biochemical engineering ; Organic chemistry ; Materials science ; Catalysis ; Reaction mechanism ; Engineering ; Adsorption Advanced Nanomaterials in Catalysis ; Advanced Photocatalysis Techniques ; Gas Sensing Nanomaterials and Sensors
Authors: Cody L. Ritt | Michelle Quien | Zitang Wei | Hagen Gress | Mohan Teja Dronadula | Kaan Altmisdort | Yuming Tu | Michael Gadaloff | N. R. Aluru | K. L. Ekinci | Scott Bunch | Michael S. Strano
Source: ChemRxiv (preprint, 2024-10-14)
Field: Materials Science — Polymers and Plastics

A Molecularly Impermeable Polymer from Two-Dimensional Polyaramids All polymers exhibit gas permeability through the free volume of entangled polymer chains. However, two-dimensional (2D) materials including graphene stack densely and can exhibit molecular impermeability. Solution-synthesized 2D polymers that exhibit the latter by poly-condensation have been a longstanding goal. Herein, we demonstrate self-supporting, spin-coated 2D polyaramid nanofilms that exhibit nitrogen permeability below 3.1E-9 Barrer, roughly 6500-fold lower than existing polymers, and similar for other gases. Optical interference during the pressurization of nanofilm-coated microwells allows measurement of mechanosensitive rim opening and sealing, creating gas-filled bulges stable exceeding 3 years. This discovery enables 2D polymer resonators with high resonance frequencies (~8 MHz) and Q factors up to 537, similar to graphene. A 60-nm coating of air-sensitive perovskites reduces the lattice degradation rate 14-fold with an oxygen permeability of 3.3E-8 Barrer. Molecularly impermeable polymers promise the next generation of barrier materials that utilize exceedingly little polymer to maximize chemical rejection, ultimately contributing to sustainable materials development. Polymer ; Materials science ; Composite material Synthesis and properties of polymers
Authors: M. Hajjaji | Abdellah Beraa | Régis Laurent | Anne‐Marie Caminade
Source: Research Square (preprint, 2024-09-25)
Field: Materials Science — Polymers and Plastics

Beidellite/montmorillonite-Phosphorus-based dendrimer organoclays :Structural features and chromate interaction analysis Montmorillonite ; Dendrimer ; Chromate conversion coating ; Phosphorus ; Materials science ; Chemistry ; Chemical engineering ; Polymer chemistry ; Organic chemistry ; Chromium ; Engineering Dendrimers and Hyperbranched Polymers ; Thermal and Kinetic Analysis ; Organometallic Compounds Synthesis and Characterization
Authors: Ahmed Hamdy | Atef S. Darwish | Hassan Nageh | Salah M. Hassan | Mohamed A. Mekewi
Source: Research Square (preprint, 2024-03-15)
Field: Chemistry — Organic Chemistry

Carboxymethyl cellulose-assisted reforming of poly (acrylic acid-co-methyl methacrylate) for boost removal of dyeing wastewater and improved stabilization of Ag nanoparticles to eradicate microbes Carboxymethyl cellulose ; Acrylic acid ; Methyl methacrylate ; Dyeing ; Cellulose ; Wastewater ; Nuclear chemistry ; Chemistry ; Methacrylate ; Chemical engineering ; Polymer chemistry ; Materials science ; Pulp and paper industry ; Waste management ; Organic chemistry ; Polymer ; Copolymer ; Engineering Nanomaterials for catalytic reactions ; Membrane Separation Technologies
Authors: Phillip Teschner | Atul Shukla | Dieter Neher
Source: arXiv (Cornell University) (preprint, 2024-11-13)
Field: Materials Science — Polymers and Plastics

A combined diffusion/rate equation model to describe charge generation in phase-separated donor-acceptor blends The power conversion efficiency (PCE) of organic solar cells (OSCs) has been largely improved by the introduction of novel non-fullerene acceptors (NFAs). Further improvements in PCE require a more comprehensive understanding of the free charge generation process. Recently, the small PCE of donor-acceptor blends with low offsets between the relevant frontier orbitals was attributed to inefficient exciton dissociation. However, another source of photocurrent loss is the competition between exciton diffusion and decay, which is particularly relevant for bilayers or bulk heterojunction blends with phase separated morphology. Here, we present an analytical model that combines exciton diffusion with a set of rate equations based on Marcus theory of charge transfer. An expression for the charge generation efficiency is derived from the steady-state solution of the model. Thereby, the intrinsic exciton lifetime is identified as a pivotal parameter to facilitate efficient charge generation in spite of a vanishing driving force for exciton dissociation. The dynamic formulation of the model is used to elucidate the characteristic time scales of charge generation. It is found that for low-offset systems, the pure diffusive times are considerably shorter than those associated with charge generation. It can therefore be concluded that when estimating domain sizes via exciton diffusion measurements, the assumption that excitons are instantaneously quenched at the donor-acceptor interface is only valid when a high driving force for exciton dissociation is present. The model is applied to the transient absorption dynamics of a PM6:Y6 blend. It is demonstrated that the charge generation dynamics are determined by the interplay between exciton diffusion and hole transfer kinetics, with an estimated Y6 domain size of 25nm, while interfacial charge transfer (CT) states separate rapidly into free charges. Diffusion ; Acceptor ; Charge (physics) ; Phase (matter) ; Diffusion equation ; Materials science ; Chemical physics ; Thermodynamics ; Chemistry ; Physics ; Condensed matter physics ; Engineering ; Quantum mechanics Conducting polymers and applications ; Semiconductor materials and interfaces
Authors: Leo S. I. Lam | Gautham Gopinath | Zichen Zhao | Shuling Wang | Chun-Shing Lee | Hai-Yao Deng | Feng Wang | Yilong Han | Cho‐Tung Yip | Chi-Hang Lam
Source: arXiv (Cornell University) (preprint, 2024-02-24)
Field: Materials Science — Ceramics and Composites

Distinguishable-particle Glassy Crystal: the simplest molecular model of glass The nature of glassy dynamics and the glass transition are long-standing problems under active debate. In the presence of a structural disorder widely believed to be an essential characteristic of structural glass, identifying and understanding key dynamical behaviors are very challenging. In this work, we demonstrate that an energetic disorder, which usually results from a structural disorder, is instead a more essential feature of glass. Specifically, we develop a distinguishable-particle glassy crystal (DPGC) in which particles are ordered in a face-centered cubic lattice and follow particle-dependent random interactions, leading to an energetic disorder in the particle configuration space. Molecular dynamics simulations in the presence of vacancy-induced particle diffusion show typical glassy behaviors. A unique feature of this molecular model is the knowledge of the complete set of inherent structures with easily calculable free energies, implying a well-understood potential energy landscape. Particle (ecology) ; Crystal (programming language) ; Materials science ; Statistical physics ; Crystallography ; Chemical physics ; Nanotechnology ; Physics ; Chemistry ; Computer science ; Geology Glass properties and applications
Authors: Nelson Mugambi | James M. Ngaruiya | Simon W. Mugo
Source: American journal of energy research (article, 2024-06-20)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Enhancing the Performance of Titanium Dioxide Compact Layer on Epitaxial Graphene and Fluorine Tin Oxide Heterojunctions We report a facile synthesis of Titanium dioxide (TiO2) modified compact layers on Fluorine Tin oxide (FTO) and graphene employing the Sol gel Doctor Blade technique, optimized systematically for enhanced solar energy conversion applications. UV-VIS spectrophotometer, a Varian 7000e FTIR, a Scanning Kelvin Probe Microscope, and Hall Effect setup evaluated the as deposited and films subjected to 1 step, 2°C/min and 1°C/min annealing rates. FTIR revealed considerable absorption at low frequencies (less than 798 cm-1) in TiO2 on graphene heterojunctions, confirming the occurrence of Ti-O and C-O-Ti bonds. The predominant anatase TiO2 characteristic was found at 438 cm-1. The TiO2 on graphene film annealed at 1 °C/min exhibited the lowest porosity (46%), as well as the highest dispersion energy (11.30 eV). As the annealing rates declined, so did the surface-to-volume energy loss ratio for all the annealed films. Graphene TiO2 annealed at 1 oC/min had a lower VELF/SELF than TiO2 on FTO, implying that an electron loses less energy when passing through the TiO2 on graphene layer than it does in TiO2 on FTO. The light absorption coefficient α and electron diffusion coefficient D of TiO2 on graphene improved to 4.637 x 103 and 1.485 x 10-4 (1 oC/min), respectively, whereas TiO2 on FTO values increased to 4.221 x 103 and 1.251 x 10-4 (1°C/min), in that order, with decreasing annealing rates. Higher values of TiO2 on graphene α and D indicate enhanced electron transition in the films. Hall Effect measurements on as-deposited and annealed TiO2 on graphene films demonstrated higher conductivity as annealing rates decreased, which was attributed to film recrystallization induced by calcination. Smoluchowski smoothing model, reveal surface scan average work functions (φ) and linear profile scan average work functions (φ) ensemble variations in granular tilts and surface slopes explaining geographic variation and distribution. Local fluctuations in φ triggered by the spatially varying concentrations of electric dipole moments are intrinsic to atomic steps and influence φ. TiO2 incorporation on graphene photoanode increased h+/e-separation, electron transport, and light absorption. The continuous conduction network on compact TiO2 nanoparticles acts as an electron leakage barrier, and the porous structure has a large specific surface area. Heterojunction ; Materials science ; Oxide ; Graphene ; Tin dioxide ; Titanium dioxide ; Tin oxide ; Epitaxy ; Layer (electronics) ; Fluorine ; Tin ; Optoelectronics ; Inorganic chemistry ; Chemical engineering ; Nanotechnology ; Composite material ; Metallurgy ; Chemistry Ga2O3 and related materials ; Supercapacitor Materials and Fabrication ; Gas Sensing Nanomaterials and Sensors
Authors: Suman Majumder | Henrik Christiansen | Wolfhard Janke
Source: arXiv (Cornell University) (preprint, 2024-05-08)
Field: Materials Science — Polymers and Plastics

Temperature and Solvent Viscosity Tune the Intermediates During the Collapse of a Polymer Dynamics of a polymer chain in solution gets significantly affected by the temperature and the frictional forces arising due to solvent viscosity. Here, using an explicit solvent framework for polymer simulation with the liberty to tune the solvent viscosity, we study the nonequilibrium dynamics of a flexible homopolymer when it is suddenly quenched from an extended coil state in good solvent to poor solvent conditions. Results from our extensive simulations reveal that depending on the temperature $T$ and solvent viscosity, one encounters long-lived sausage-like intermediates following the usual pearl-necklace intermediates. Use of shape factors of polymers allows us to disentangle these two distinct stages of the overall collapse process, and the corresponding relaxation times. The relaxation time $τ_s$ of the sausage stage, which is the rate-limiting stage of the overall collapse process, follows an anti-Arrhenius behavior in the high-$T$ limit, and the Arrhenius behavior in the low-$T$ limit. Furthermore, the variation of $τ_s$ with the solvent viscosity provides evidence of internal friction of the polymer, that modulates the overall collapse significantly, analogous to what is observed for relaxation rates of proteins during their folding. This suggests that the origin of internal friction in proteins is plausibly intrinsic to its polymeric backbone rather than other specifications. Solvent ; Viscosity ; Polymer ; Chemistry ; Materials science ; Chemical engineering ; Thermodynamics ; Polymer science ; Polymer chemistry ; Organic chemistry ; Physics ; Composite material ; Engineering Polymer crystallization and properties ; Polymer Science and PVC ; Rheology and Fluid Dynamics Studies
Authors: Bowen Zhou | Kenji Watanabe | Takashi Taniguchi
Source: arXiv (Cornell University) (preprint, 2024-11-20)
Field: Materials Science — Materials Chemistry

Extraordinary magnetoresistance in high-quality graphene devices with daisy chains and Fermi-level pinning We studied daisy-chained extraordinary magnetoresistance (EMR) devices based on high quality monolayer graphene encapsulated in hexagonal boron nitride (h-BN) at room temperature. The largest magnetoresistance (MR) achieved in our devices is 4.6 x 10^7 %, the record for EMR devices to date. The magnetic field sensitivity, dR/dB, reaches 104 kohm/T, exceeding the previous record set by encapsulated graphene by more than 300 %, and is comparable with state-of-the-art graphene Hall sensors at cryogenic temperatures (4.2 K). We demonstrate that daisy chaining multiple EMR devices is a new way to reach arbitrarily high sensitivity and signal-to-noise ratio, and extremely small noise equivalent field for weak magnetic field detection. Finally, we show the evidence of metal contact-induced Fermi-level pinning in the sample and its influence on graphene properties, current distribution and EMR performance. We highlight the EMR geometry as an interesting alternative to the Hall geometry for fundamental physics studies. Magnetoresistance ; Graphene ; Condensed matter physics ; Materials science ; Quality (philosophy) ; Nanotechnology ; Physics ; Magnetic field ; Quantum mechanics Graphene research and applications ; Quantum and electron transport phenomena ; Magnetic Field Sensors Techniques
Authors: V.A. Golovin | A.B. Il’in | O.B. Butusov
Source: International Journal of Corrosion and Scale Inhibition (article, 2024-12-01)
Field: Materials Science — General Materials Science

Quantitative assessment of the development of operational defects in polymer anticorrosive composite coatings in aggressive environments The effect of a rapidly diffusing medium, the nature of the polymer matrix, the filler particle size, and the nature of the dispersed filler on the change in the size and structure of the reinforcing frame of the dispersed filler of epoxy composites is investigated. It is shown that the local X-ray spectral analysis method is informative for conducting accelerated one-day diffusion tests at room temperature for compositions of industrial anticorrosive coatings. The results obtained can serve as a physicochemical basis for explaining the relationship between the structure of epoxy composites and the properties of the anticorrosive coatings obtained from them. Corrosion ; Materials science ; Composite number ; Polymer ; Composite material ; Forensic engineering ; Engineering Material Properties and Applications ; Material Properties and Failure Mechanisms ; Polymer Science and Applications
Authors: Jean-Baptiste Marceau | Duc-Minh Ta | Antonio Aguilar | Annick Loiseau | Richard Martel | Pierre Bon | Raphaël Voituriez | Gaëlle Recher | Étienne Gaufrès
Source: arXiv (Cornell University) (preprint, 2024-02-27)
Field: Materials Science — Materials Chemistry

Forming 1D Periodic J-aggregates by Mechanical Bending of BNNTs: Evidence of Activated Molecular Diffusion Driving molecular assembly into micrometer-scale patterns is key for defining advanced materials of interest in various fields, including life sciences, photovoltaics, and quantum photonics. However, the driving process competes with other forces, such as Brownian motion, ripening phenomena, capillary forces, and non-specific adsorption. Here we report on a guided diffusion mechanism of luminescent dye molecules encapsulated inside boron nitride nanotubes (BNNTs). Correlative measurements between BNNT bending and molecular position along the BNNT axis reveal an efficient and long-range migration of dyes from curved to straight regions of the nanotube. This curvature activated diffusion forms clusters of bright J-aggregates in periodic patterns of well-defined spacing and length. A phenomenological model of guided molecular transport in bended BNNTs is used to describe this directed 1D diffusion inside BNNT. It is shown to accurately predict the position and morphologies of a J-aggregate as a function of nanotube length. Coupling topological stimuli to 1D molecular diffusion at the nanoscale is here presented as an interesting tool capable of reconfiguring various emissive patterns of functional molecules at the mesoscopic scale. Mesoscopic physics ; Materials science ; Chemical physics ; Nanotechnology ; Bending ; Diffusion ; Nanoscopic scale ; Molecular dynamics ; Curvature ; Brownian motion ; Computational chemistry ; Chemistry ; Physics ; Condensed matter physics ; Composite material Boron and Carbon Nanomaterials Research ; Thermal properties of materials ; Graphene research and applications
Authors: Dylan Jennings | Moritz L. Weber | Ansgar Meise | Tobias Binninger | Conor Jason Price | Moritz Kindelmann | Ivar E. Reimanis | Hiroaki Matsumoto | Pengfei Cao | Regina Dittman | Piotr M. Kowalski | Marc Heggen | Olivier Guillon | Joachim Mayer | Felix Gunkel | Wolfgang Rheinheimer
Source: ChemRxiv (preprint, 2024-07-11)
Field: Materials Science — Materials Chemistry

Direct Atomic-Scale Investigation of the Coarsening Mechanisms of Exsolved Catalytic Nanoparticles Exsolution-active catalysts allow for the formation of highly active metallic nanoparticles, yet their long-term thermal stability remains a challenge. In this work, the dynamics of exsolved Ni nanoparticles are probed in situ with atomically resolved secondary electron imaging in an environmental STEM. STEM pre-characterization shows embedded NiOx nanostructures within the parent oxide. Subsequent in situ exsolution demonstrates that two populations of exsolved particles form with distinct metal-support interactions and coarsening behaviors. Nanoparticle migration which fits random-walk kinetics is observed, and particle behavior is shown to be analogous to a classical wetting model. Additionally, DFT calculations indicate that particle motion is facilitated by the support oxide. Ostwald ripening processes are visualized simultaneously to migration, including particle redissolution and particle ripening. Atomic units ; Materials science ; Scale (ratio) ; Nanoparticle ; Nanotechnology ; Physics Catalytic Processes in Materials Science ; Copper-based nanomaterials and applications ; nanoparticles nucleation surface interactions