jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Mohamed I. A. Ibrahim | Islam M. Abdelmonem | Laila A. Mohamed | Mohamed A. Gizawy | Essam Metwally
Source: Polymer-Plastics Technology and Materials (article, 2024-03-29)
Field: Materials Science — Polymers and Plastics

Synthesis and characterization of alginate-polyacrylic acid/multiwalled carbon nanotubes composite with efficient removal for nigrosine dye The current study detailed the efficacy of a simply prepared alginate-polyacrylic acid/functionalized multiwalled carbon nanotubes (Alg-PAA/f-MWCNTs) composite for adsorption of nigrosine dye (acid black II) from aqueous environments. Firstly, preparation of the Alg-PAA/f-MWCNTs composite was achieved via gamma radiation-induced template polymerization of AA onto the Alg/f-MWCNTs surface. The maximum grafting efficiency (GE%) of AA onto the surface of Alg/f-MWCNTs was ~ 82% under the optimized conditions: (2.5 wt% Alg, 30 wt% AA, 0.5 wt% f-MWCNTs, 0.6 wt% N,N’-methylenebisacrylamide (NMBA), and irradiation dose ~ 20 kGy). The structural characteristics, thermal features as well as the morphological appearance of the Alg-PAA/f-MWCNTs composite were validated using different analyses including FTIR, TGA, DTA, XRD and SEM. Additionally, the composite exhibited uniform particle size distribution (~150.7 nm), point of zero charge at pH = 6.28, and negative Zeta potentials of a minimum at pH = 2. The adsorption batch experiments showed good adsorption capacity for the nigrosine dye from their aqueous media with adsorption efficiency up to 83% using the batch technique at pH = 2.0 for 420 min. The adsorption of nigrosine dye onto Alg-PAA/f-MWCNTs is favorable thermodynamically, obeying the Freundlich isotherm model and controlled by a chemisorption mechanism. Additionally, the composite showed a good regeneration ability up to five times with almost the same removal of ~80%. The results demonstrated that the Alg-PAA/f-MWCNTs composite could be a promising candidate for the removal of nigrosine dye from industrial aqueous environments. Polyacrylic acid ; Composite number ; Characterization (materials science) ; Materials science ; Carbon nanotube ; Chemical engineering ; Nanotechnology ; Composite material ; Polymer Conducting polymers and applications ; Electrochemical sensors and biosensors ; Supramolecular Self-Assembly in Materials
Authors: Danny Reidenbach | Aditi S. Krishnapriyan
Source: Journal of Chemical Information and Modeling (article, 2024-12-17)
Field: Materials Science — Materials Chemistry

CoarsenConf: Equivariant Coarsening with Aggregated Attention for Molecular Conformer Generation Molecular conformer generation (MCG) is an important task in cheminformatics and drug discovery. The ability to efficiently generate low-energy 3D structures can avoid expensive quantum mechanical simulations, leading to accelerated virtual screenings and enhanced structural exploration. Several generative models have been developed for MCG, but many struggle to consistently produce high-quality conformers for meaningful downstream applications. To address these issues, we introduce CoarsenConf, which coarse-grains molecular graphs based on torsional angles and integrates them into an SE(3)-equivariant hierarchical variational autoencoder. Through equivariant coarse-graining, we aggregate the fine-grained atomic coordinates of subgraphs connected via rotatable bonds, creating a variable-length coarse-grained latent representation. Our model uses a novel aggregated attention mechanism to restore fine-grained coordinates from the coarse-grained latent representation, enabling efficient generation of accurate conformers. Furthermore, we evaluate the chemical and biochemical quality of our generated conformers on multiple downstream applications, including property prediction and large-scale oracle-based protein docking. Overall, CoarsenConf generates more accurate conformer ensembles compared to prior generative models. Conformational isomerism ; Computer science ; Cheminformatics ; Virtual screening ; Equivariant map ; Generative model ; Representation (politics) ; Theoretical computer science ; Molecular dynamics ; Biological system ; Artificial intelligence ; Generative grammar ; Chemistry ; Computational chemistry ; Mathematics ; Molecule Machine Learning in Materials Science ; Protein Structure and Dynamics ; Computational Drug Discovery Methods
Authors: Adriana Coricello | Alanya J. Nardone | Antonio Lupia | Carmen Gratteri | Matthijn Vos | Vincent Chaptal | Stefano Alcaro | Wen Zhu | Yuichiro Takagi | Nigel G. J. Richards
Source: Nature Communications (article, 2024-12-03)
Field: Materials Science — Materials Chemistry

3D variability analysis reveals a hidden conformational change controlling ammonia transport in human asparagine synthetase Advances in X-ray crystallography and cryogenic electron microscopy (cryo-EM) offer the promise of elucidating functionally relevant conformational changes that are not easily studied by other biophysical methods. Here we show that 3D variability analysis (3DVA) of the cryo-EM map for wild-type (WT) human asparagine synthetase (ASNS) identifies a functional role for the Arg-142 side chain and test this hypothesis experimentally by characterizing the R142I variant in which Arg-142 is replaced by isoleucine. Support for Arg-142 playing a role in the intramolecular translocation of ammonia between the active site of the enzyme is provided by the glutamine-dependent synthetase activity of the R142 variant relative to WT ASNS, and MD simulations provide a possible molecular mechanism for these findings. Combining 3DVA with MD simulations is a generally applicable approach to generate testable hypotheses of how conformational changes in buried side chains might regulate function in enzymes. Asparagine ; Asparagine synthetase ; Conformational change ; Biophysics ; Biochemistry ; Chemistry ; Active site ; Glutamine synthetase ; Glutamine ; Enzyme ; Biology ; Amino acid Enzyme Structure and Function ; Amino Acid Enzymes and Metabolism ; Biochemical and Molecular Research
Authors: Rubén Mendoza‐Cruz | Juan Pedro Palomares-Báez | S. López-López | J.M. Montejano‐Carrizales | José Luis Rodríguez‐López | Miguel José–Yacamán | Lourdes Bazán-Díaz
Source: Nano Letters (article, 2024-04-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Experimental High-Resolution Observation of the Truncated Double-Icosahedron Structure: A Stable Twinned Shell in Alloyed Au–Ag Core@Shell Nanoparticles Given the binary nature of nanoalloy systems, their properties are dependent on their size, shape, structure, composition, and chemical ordering. When energy and entropic factors for shapes and structure variations are considered in nanoparticle growth, the spectra of shapes become so vast that even metastable arrangements have been reported under ambient conditions. Experimental and theoretical variations of multiply twinned particles have been observed, from the Ino and Marks decahedra to polyicosahedra and polydecahedra with comparable energetic stability among them. Herein, we report the experimental production of a stable doubly truncated double-icosahedron structure (TdIh) in Au-Ag nanoparticles, in which a twinned Ag-rich alloyed shell is reconstructed on a Au-Ag alloyed Ino-decahedral core. The structure, chemical composition, and growth pathway are proposed on the basis of high-angle annular dark-field scanning transmission electron microscopy analysis and excess energy calculations, while its structural stability is estimated by large-scale atomic molecular dynamics simulations. This novel nanostructure differs from other structures previously reported. Metastability ; Nanostructure ; Materials science ; Nanoparticle ; Shell (structure) ; Transmission electron microscopy ; Chemical physics ; Scanning transmission electron microscopy ; High-resolution transmission electron microscopy ; Molecular dynamics ; Atomic units ; Crystallography ; Molecular physics ; Nanotechnology ; Chemistry ; Computational chemistry ; Physics ; Composite material Gold and Silver Nanoparticles Synthesis and Applications ; nanoparticles nucleation surface interactions ; Quantum Dots Synthesis And Properties
Authors: Fahim Hamidouche | Zohra Ghebache | Jean‐Claude Leprêtre | Nacer‐Eddine Djelali
Source: Polymers (article, 2024-03-27)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Montmorillonite/Poly(Pyrrole) for Low-Cost Supercapacitor Electrode Hybrid Materials Conductive polymers such as polypyrrole have been widely used as pseudo-capacitive electrodes for supercapacitors. This work demonstrates a simple method to improve the performance of conductive polymer electrodes by adding montmorillonite in order to perform capacitive behavior. Conductive composite polymers (CCPs) based on montmorillonite/polypyrrole (MMT/PPy(Cl)) have been synthesized by polymerization using FeCl<sub>3</sub> as an oxidizing agent. During the preparation of CCP, the effect of MMT/pyrrole mass ratio and the influence of the amount of added H<sup>+</sup> and temperature of the synthesis medium on the electrochemical performance of the composite have been investigated. The investigation associated with conductivity measurement allowed us to determine the best conditions to reach a high specific capacitance of 465 F gr<sup>-1</sup> measured by cyclic voltammetry with respect to the CCP synthesized at ambient temperature (220 F gr<sup>-1</sup>) and a 35% increase in capacity compared to its homologue synthesized in neutral conditions at a low temperature. These performances have been advantageously correlated both to the edge acidity of the host material and to the evolution of its conductivity according to the preparation conditions. The galvanostatic charge/discharge tests also confirm the stability of the obtained composite, and a capacitance of 325 F g<sup>-1</sup> for the best CCP is recorded with a regime of 1 A g<sup>-1</sup>. In addition, the durability of the device shows that the proposed material has a relatively good stability during cycling. Supercapacitor ; Montmorillonite ; Materials science ; Electrode ; Pyrrole ; Chemical engineering ; Electrochemistry ; Composite material ; Chemistry ; Organic chemistry ; Engineering ; Physical chemistry Supercapacitor Materials and Fabrication ; Conducting polymers and applications ; Advanced Sensor and Energy Harvesting Materials
Authors: Hedyeh Hosseinzadeh | Kurosh Rad‐Moghadam | Morteza Mehrdad | Somayeh Rouhi
Source: Scientific Reports (article, 2024-01-05)
Field: Chemistry — Organic Chemistry

Starch mediates and cements densely magnetite-coating of talc, giving an efficient nano-catalyst for three-component synthesis of imidazo[1,2-c]quinazolines Hot-water-soluble starch (HWSS) was used as a powerful cementing material to produce nano-size conglomerates of talc and magnetite nanoparticles. Coordination of HWSS hydroxyl groups to iron atoms at surface of magnetite leads to grafting and encapsulation of its nanoparticles. The resulting nano-complex showed a higher loading capacity on talc than pristine magnetite nanoparticles. Only a minute amount of HWSS was detected in the fabricated nano-composite Talc\HWSS@Fe<sub>3</sub>O<sub>4</sub>. XPS study suggests a considerable interaction between HWSS and Fe<sub>3</sub>O<sub>4</sub> nanoparticles, upon which some of the Fe<sup>+3</sup> atoms on surface of Fe<sub>3</sub>O<sub>4</sub> are reduced into Fe<sup>+2</sup> atoms. ATR FT-IR spectra of the nano-composite revealed significant delamination of talc sheets on interaction with HWSS-coated Fe<sub>3</sub>O<sub>4</sub> nanoparticles. The nano-composite displayed an efficient catalytic activity in the synthesis of new imidazo[1,2-c]quinazoline derivatives via Grobke-Blackburn-Bienaymé three-component reaction of 4-aminoquinazoline, arylaldehydes and isocyanide. The efficiency of the method was exemplified by synthesizing 7 new products in fairly high yields (68-83%) within short reaction times (24-30 min) using a catalytic amount of the catalyst under solvent-free condition at 120 °C. Clean and fast synthesis of the products and convenient separation of the robust nano-catalyst are the prominent advantages of the present method. The nano-catalyst was properly characterized. Talc ; Catalysis ; Nanoparticle ; Magnetite ; Chemical engineering ; Composite number ; Nano- ; Materials science ; X-ray photoelectron spectroscopy ; Coating ; Chemistry ; Nanotechnology ; Composite material ; Organic chemistry ; Metallurgy Quinazolinone synthesis and applications ; Multicomponent Synthesis of Heterocycles ; Synthesis and Characterization of Heterocyclic Compounds
Authors: Nicolò Riboni | Erika Ribezzi | Federica Bianchi | Maria Careri
Source: Molecules (article, 2024-06-12)
Field: Chemistry — Analytical Chemistry

Supramolecular Materials as Solid-Phase Microextraction Coatings in Environmental Analysis Solid-phase microextraction (SPME) has been widely proposed for the extraction, clean-up, and preconcentration of analytes of environmental concern. Enrichment capabilities, preconcentration efficiency, sample throughput, and selectivity in extracting target compounds greatly depend on the materials used as SPME coatings. Supramolecular materials have emerged as promising porous coatings to be used for the extraction of target compounds due to their unique selectivity, three-dimensional framework, flexible design, and possibility to promote the interaction between the analytes and the coating by means of multiple oriented functional groups. The present review will cover the state of the art of the last 5 years related to SPME coatings based on metal organic frameworks (MOFs), covalent organic frameworks (COFs), and supramolecular macrocycles used for environmental applications. Solid-phase microextraction ; Supramolecular chemistry ; Extraction (chemistry) ; Materials science ; Coating ; Selectivity ; Solid phase extraction ; Sample preparation ; Porosity ; Analyte ; Nanotechnology ; Porous medium ; Chromatography ; Chemistry ; Organic chemistry ; Molecule ; Gas chromatography–mass spectrometry ; Mass spectrometry Analytical chemistry methods development ; Radioactive element chemistry and processing ; Molecular Sensors and Ion Detection
Authors: Sara Sheikhi | Wylie Stroberg | James D. Hogan
Source: Ceramics (article, 2024-02-21)
Field: Materials Science — Materials Chemistry

Temperature-Dependent Elastic Properties of B4C from First-Principles Calculations and Phonon Modeling Boron carbide plays a crucial role in various extreme environment applications, including thermal barrier coatings, aerospace applications, and neutron absorbers, because of its high thermal and chemical stability. In this study, the temperature-dependent elastic stiffness constants, thermal expansion coefficient, Helmholtz free energy, entropy, and heat capacity at a constant volume (Cv) of rhombohedral B4C have been predicted using a quasi-harmonic approach. A combination of volume-dependent first-principles calculations (density functional theory) and first-principles phonon calculations in the supercell framework has been performed. Good agreement between the elastic constants and structural parameters from static calculations is observed. The calculated thermodynamic properties from phonon calculations show trends that align with the literature. As the temperature rises, the predicted free energy follows a decreasing trend, while entropy and Cv follow increasing trends with temperature. Comparisons between the predicted room temperature thermal expansion coefficient (TEC) (7.54×10−6 K−1) and bulk modulus (228 GPa) from the quasi-harmonic approach and literature results from experiments and models are performed, revealing that the calculated TEC and bulk modulus fall within the established range from the limited set of data from the literature (TEC = 5.73–9.50 ×10−6 K−1, B = 221–246 GPa). Temperature-dependent Cijs are predicted, enabling stress analysis at elevated temperatures. Overall, the outcomes of this study can be used when performing mechanical and thermal stress analysis (e.g., space shielding applications) and optimizing the design of boron carbide materials for elevated temperature applications. Phonon ; Materials science ; Condensed matter physics ; Physics Boron and Carbon Nanomaterials Research ; Advanced ceramic materials synthesis ; Aluminum Alloys Composites Properties
Authors: Mathieu Vidal | Jyoti Pandey | Javier Navarro‐Ruiz | Joris Langlois | Yann Tison | Takeharu Yoshii | Keigo Wakabayashi | Hirotomo Nishihara | Anatoly I. Frenkel | Eli Stavitski | Martine Urrutigoı̈ty | Cristian H. Campos | Cyril Godard | Tobias Placke | Iker Del Rosal | Iann C. Gerber | Valeri Petkov | Philippe Serp
Source: Chemistry - A European Journal (article, 2024-06-25)
Field: Materials Science — Materials Chemistry

Probing Basal and Prismatic Planes of Graphitic Materials for Metal Single Atom and Subnanometer Cluster Stabilization Supported metal single atom catalysis is a dynamic research area in catalysis science combining the advantages of homogeneous and heterogeneous catalysis. Understanding the interactions between metal single atoms and the support constitutes a challenge facing the development of such catalysts, since these interactions are essential in optimizing the catalytic performance. For conventional carbon supports, two types of surfaces can contribute to single atom stabilization: the basal planes and the prismatic surface; both of which can be decorated by defects and surface oxygen groups. To date, most studies on carbon-supported single atom catalysts focused on nitrogen-doped carbons, which, unlike classic carbon materials, have a fairly well-defined chemical environment. Herein we report the synthesis, characterization and modeling of rhodium single atom catalysts supported on carbon materials presenting distinct concentrations of surface oxygen groups and basal/prismatic surface area. The influence of these parameters on the speciation of the Rh species, their coordination and ultimately on their catalytic performance in hydrogenation and hydroformylation reactions is analyzed. The results obtained show that catalysis itself is an interesting tool for the fine characterization of these materials, for which the detection of small quantities of metal clusters remains a challenge, even when combining several cutting-edge analytical methods. Catalysis ; Cluster (spacecraft) ; Carbon fibers ; Rhodium ; Hydroformylation ; Atom (system on chip) ; Transition metal ; Materials science ; Characterization (materials science) ; Nanotechnology ; Metal ; Heterogeneous catalysis ; Cluster chemistry ; Oxygen storage ; Chemical physics ; Chemistry ; Chemical engineering ; Organic chemistry ; Composite material ; Metallurgy ; Composite number Catalytic Processes in Materials Science ; Machine Learning in Materials Science ; Nanocluster Synthesis and Applications
Authors: Laura Rieger | Klemen Zelič | Igor Mele | Tomaž Katrašnik | Arghya Bhowmik
Source: Scientific Data (article, 2024-11-23)
Field: Materials Science — Materials Chemistry

Setting the standard for machine learning in phase field prediction: a benchmark dataset and baseline metrics Phase field models are an important mesoscale method that serves as a bridge between the atomic scale and the macroscale, used for modeling complex phenomena at the microstructure level. Machine learning can be employed to accelerate these simulations, enabling faster and more efficient analyses. However, the development of new machine learning algorithms depends on access to extensive datasets. This work introduces an accessible and well-documented dataset aimed at benchmarking new machine learning algorithms. We validate the dataset with a benchmark using U-Net regression, a widely used neural network architecture. Although direct comparisons are limited by the lack of existing benchmarks, our model's error metrics are competitive with previous work and generalize across multiple domain sizes. This contribution provides a valuable resource for future efforts in machine learning model development for phase field simulations and demonstrates the potential of U-Net regression, highlighting the scope for novel method development in this area. Baseline (sea) ; Benchmark (surveying) ; Computer science ; Field (mathematics) ; Artificial intelligence ; Machine learning ; Phase (matter) ; Data mining ; Mathematics ; Geography ; Cartography ; Physics ; Geology Solidification and crystal growth phenomena ; High Temperature Alloys and Creep ; Nuclear Materials and Properties
Authors: Ayesha Kausar
Source: Advances in Materials Science (article, 2024-09-01)
Field: Materials Science — Polymers and Plastics

Competence of Carbonaceous Fibers/Nanofillers (Graphene, Carbon Nanotube) Reinforced Shape Memory Composites/Nanocomposites Towards Aerospace—Existent Status and Expansions Abstract Shape memory or stimuli responsive polymers have established a unique grouping of smart materials. The technical merit of these polymers has been evaluated in aerospace sector, since last few decades. Particularly, the stimuli responsive polymers render inherent competences to recuperate the structural damages in exterior/interior space architectures. In this context, both the thermoplastics as well as thermosetting polymers depicted essential stimuli responsive behaviour. As interpreted in this state-of the-art review, the carbonaceous reinforcement like carbon fibers and nano-reinforcements including nanocarbons (graphene, carbon nanotube) have been employed in the shape recovering matrices. The performance of ensuing shape retrieving aerospace materials was seemed to be reliant on the polymer chain crosslinking effects, filler/nanofiller dispersal/alignment, microstructural specs, interfacial contour and interactions, and processing techniques used. Consequently, the shape actuations of polymer/carbon fiber composites were found to be instigated and upgraded through the inclusion of nanocarbon nano-additives. The ensuing high-tech shape memory composites/nanocomposites have anomalous significance for various aero-structural units (fuselage, wings, antennas, engines, etc.) due to prevention of possible thermal/shock/impact damages. Future implications of carbonaceous shape memory composites/nanocomposites in aerospace demands minimizing the structure-property-performance challenges and large scale fabrication for industrial scale utilizations. In this way, deployment of carbonaceous nanofiller/filler based composites revealed enormous worth due to low density, anti-fatigue/wear, anti-corrosion, non-flammability, self-healing, and extended durability and long life operations. However, there are certain challenges associated with the use of nanocarbons and ensuing nanocomposites in this field markedly the adoption of appropriate carbon fiber coating technique, aggregation aptitude of nanocarbons, additional processing steps/cost, nanoparticle initiated invisible defects/voids, difficulty in machinability operations due to presence of nanoparticles, and corrosion risk of composite structures in contact with metal surfaces. By overcoming these hinderances, nanoparticles modified carbon fiber based composites can be promising towards a new look of upcoming modernized aerospace industry. Materials science ; Composite material ; Carbon nanotube ; Nanocomposite ; Graphene ; Aerospace ; Nanotechnology ; Aerospace engineering ; Engineering Polymer composites and self-healing ; Carbon Nanotubes in Composites ; Smart Materials for Construction