jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Chiara De Luca | Greta Compagnin | Chiara Nosengo | Giulia Mazzoccanti | Francesco Gasparrini | Alberto Cavazzini | Martina Catani | Simona Felletti
Source: Analytical and Bioanalytical Chemistry (article, 2024-02-15)
Field: Chemistry — Spectroscopy

Novel insights into the dependence of adsorption-desorption kinetics on particle geometry in chiral chromatography The existence of slow adsorption-desorption kinetics in chiral liquid chromatography is common knowledge. This may significantly contribute to worsening the efficiency and kinetic performance of a chromatographic run, especially when high flow rates are employed. Many attempts and protocols have been proposed to access this term, the so-called <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>c</mml:mi> <mml:mrow><mml:mi>ads</mml:mi></mml:mrow> </mml:msub> </mml:math> , but they are based on different (theoretical) assumptions. As a consequence, no official method is available for the estimation of the adsorption-desorption kinetics term. In this work, a novel approach to access <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>c</mml:mi> <mml:mrow><mml:mi>ads</mml:mi></mml:mrow> </mml:msub> </mml:math> is presented. This procedure combines experimental results obtained with kinetic and thermodynamic measurements. The investigations have been performed on two zwitterionic teicoplanin chiral stationary phases (CSPs) based on 1.9 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>μ</mml:mi></mml:math> m fully porous and 2.0 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>μ</mml:mi></mml:math> m superficially porous particles (FPPs and SPPs), using Z-D,L-Methionine as probe molecule. Kinetic studies have been performed through the combination of both stop-flow and dynamic measurements, while adsorption isotherms have been calculated through Inverse Method. This study has confirmed that, on both particle formats, analyte diffusion on the surface of the particle is negligible, meaning that adsorption is localized, and it has been demonstrated that adsorption-desorption kinetics is strongly dependent on particle geometry and, in particular, on the loading of chiral selector. These findings are fundamental not only to unravel novel aspects of the complex enantiorecognition mechanism but also to optimize the employment of CSPs for ultra-fast and preparative applications. Adsorption ; Desorption ; Kinetics ; Algorithm ; Chemistry ; Analytical Chemistry (journal) ; Materials science ; Chromatography ; Physics ; Computer science ; Physical chemistry Analytical Chemistry and Chromatography ; Microfluidic and Capillary Electrophoresis Applications ; Chromatography in Natural Products
Authors: Meriem Bouguezzi | Jean-François Scheid | Danielle Hilhorst | Hiroshi Matano | Christian Bataillon | Florence Lequien | Fabien Rouillard
Source: Electrochimica Acta (article, 2024-01-12)
Field: Materials Science — Materials Chemistry

Anodic dissolution model with diffusion–migration transport for simulating localized corrosion Corrosion ; Anode ; Dissolution ; Diffusion ; Materials science ; Metallurgy ; Chemical engineering ; Chemical physics ; Chemistry ; Electrode ; Thermodynamics ; Physical chemistry ; Engineering ; Physics Anodic Oxide Films and Nanostructures ; Corrosion Behavior and Inhibition ; Hydrogen embrittlement and corrosion behaviors in metals
Authors: Faheem Muhammad | Xiwen Chen | Qi Sun | Yuting Wang | Dongze Mo | Yuyang Li | Leiying Miao | Hui Wei
Source: Angewandte Chemie International Edition (article, 2024-12-23)
Field: Materials Science — Biomaterials

Topotactic Transformation in Fe<sub>3</sub>O<sub>4</sub> Induces Spontaneous Growth of Compositionally Diverse Nanostructures Topotactic transformation is an emerging strategy for synthesizing materials with exotic functional properties. In this report, instead of producing new crystals with related structures, we exploited the topotactic transformation phenomenon to spontaneously produce compositionally diverse nanostructures on the transforming substrate. The surface of magnetite nanoparticles (Fe<sub>3</sub>O<sub>4</sub> NPs) is topotactically transformed into maghemite (γ-Fe<sub>2</sub>O<sub>3</sub>). Benefiting from such oxidation susceptibility of ultrasmall Fe<sub>3</sub>O<sub>4</sub> NPs, we achieved spontaneous growth of metals (Ag, Au, Pt, and Pd), a non-metal (Se), and a metal oxide (MnO<sub>2</sub>) based nanostructures onto the surface of Fe<sub>3</sub>O<sub>4</sub>. No spontaneous growth of nanostructures was observed when the oxidized Fe<sub>3</sub>O<sub>4</sub> NPs were tested, likely due to the loss of the Fe<sup>2+</sup>-associated mobile electrons. The obtained nanostructures displayed appreciable antioxidant activities, which we utilized to effectively treat inflammation in the intestines. It is anticipated that this synthetic route, based on topotactic transformation, represents a significant advancement in synthesizing various chemically diverse hetero-nanostructures. Nanostructure ; Maghemite ; Nanotechnology ; Materials science ; Magnetite ; Substrate (aquarium) ; Transformation (genetics) ; Metal ; Oxide ; Nanoparticle ; Chemical engineering ; Chemistry ; Metallurgy Nanoparticle-Based Drug Delivery ; Nanomaterials for catalytic reactions ; Nanoparticles: synthesis and applications
Authors: Juan Bisquert | Nir Tessler
Source: Advanced Functional Materials (article, 2024-12-17)
Field: Materials Science — Polymers and Plastics

Transient Current Responses of Organic Electrochemical Transistors: Evaluating Ion Diffusion, Chemical Capacitance, and Series Elements Abstract For the successful implementation of organic electrochemical transistors in neuromorphic computing, bioelectronics, and real‐time sensing applications it is essential to understand the factors that influence device switching times. This work describes a physical‐electrochemical model of the transient response to a step of the gate voltage. The model incorporates 1) ion diffusion inside the channel that governs the electronic conductivity, 2) horizontal electron transport, and 3) the external elements (capacitance, ionic resistance) of the ion dynamics in the electrolyte. This work finds a general expression of two different time constants that determine the vertical insertion process in terms of the transport/polarization parameters, in addition to the electronic transit time. The work highlights the central role of the chemical capacitance in determining the modulation of the lateral conductivity. The different types of response of the drain current are classified, and the significance for synaptic operation in neuromorphic circuits is discussed. The model is confirmed by detailed simulations that enable to visualize the different ions distributions and dynamics. Materials science ; Capacitance ; Diffusion ; Current (fluid) ; Ion ; Electrochemistry ; Transient (computer programming) ; Transistor ; Series (stratigraphy) ; Chemical physics ; Optoelectronics ; Nanotechnology ; Electrical engineering ; Thermodynamics ; Electrode ; Physical chemistry ; Voltage ; Computer science Conducting polymers and applications ; Analytical Chemistry and Sensors ; Advanced Memory and Neural Computing
Authors: Martina Cotti | Amelie Stahlbuhk | Hartmut Fischer | Michael Steiger | O.C.G. Adan | Henk Huinink
Source: Crystal Growth & Design (article, 2024-12-09)
Field: Materials Science — Materials Chemistry

Mechanism and Kinetics of Hydration of CuSO<sub>4</sub>·H<sub>2</sub>O in the Presence of an Intermediate Step The hydration of salt hydrates is often described as a solution mediated nucleation and growth mechanism, occurring between a reagent and a product in thermodynamic equilibrium with each other. If a system possesses more than one hydrate phase, the kinetic pathway may involve additional mechanisms due to the formation of intermediate hydrate species. We elected CuSO<sub>4</sub> as our model system and analyzed the pathway leading from CuSO<sub>4</sub>·H<sub>2</sub>O (C1H) to CuSO<sub>4</sub>·5H<sub>2</sub>O (C5H), while CuSO<sub>4</sub>·3H<sub>2</sub>O (C3H) being a possible intermediate. We found that C1H hydration is mediated by the formation of C3H and that C5H does not nucleate directly from C1H, at the studied conditions. The hydration pathway therefore is characterized by the same mechanism occurring twice, nucleation and growth of C3H and nucleation and growth of C5H. Analysis of the hydration kinetics of C1H revealed that C5H nucleates rapidly from C3H, as if the metastability of C3H was reduced when starting from C1H. Therefore, we concluded that the hydration kinetics of C1H are probably controlled by the growth process of C5H. Despite being controlled by a single reaction process, we show that a single front 1D diffusion model is insufficient to describe the reaction kinetics at the tablet level. Understanding of these complex transformations is necessary to evaluate the suitability of these reactions for application, in particular with respect to the achieved power output. Chemistry ; Nucleation ; Kinetics ; Hydrate ; Metastability ; Reagent ; Thermodynamics ; Diffusion ; Physical chemistry ; Organic chemistry Crystallization and Solubility Studies ; Chemical and Physical Properties in Aqueous Solutions ; Thermal and Kinetic Analysis
Authors: Mohammad El Loubani | Gene Yang | Seyed Morteza Taghavi Kouzehkanan | Tae-Sik Oh | S. K. Balijepalli | Dongkyu Lee
Source: Materials Advances (article, 2024-01-01)
Field: Materials Science — Polymers and Plastics

Influence of redox engineering on the trade-off relationship between thermopower and electrical conductivity in lanthanum titanium based transition metal oxides Metal exsolution, driven by the unique redox flexibility and defect chemistry of oxides, breaks the tradeoff between thermopower and electrical conductivity by enabling synergistic energy filtering and the injection of high-mobility electrons. Lanthanum ; Transition metal ; Titanium ; Electrical resistivity and conductivity ; Materials science ; Seebeck coefficient ; Redox ; Metal ; Conductivity ; Inorganic chemistry ; Metallurgy ; Chemistry ; Composite material ; Electrical engineering ; Physical chemistry ; Thermal conductivity ; Catalysis ; Organic chemistry Transition Metal Oxide Nanomaterials ; Advancements in Solid Oxide Fuel Cells ; Pigment Synthesis and Properties
Authors: Wentao Huang | Lan Chen
Source: Electronics (article, 2024-04-03)
Field: Materials Science — Materials Chemistry

A Compact Model of Carbon Nanotube Field-Effect Transistors for Various Sizes with Bipolar Characteristics Carbon nanotubes have excellent electrical properties and can be used as a new generation of semiconductor materials. This paper presents a compact model for carbon nanotube field-effect transistors (CNTFETs). The model uses a semi-empirical approach to model the current–voltage properties of CNTFETs with gate lengths exceeding 100 nm. This study introduces an innovative approach by proposing physical parametric reference lengths (Lref), which facilitate the integration of devices of varying sizes into a unified modeling framework. Furthermore, this paper develops models for the bipolar properties of carbon nanotube devices, employing two distinct sets of model parameters for enhanced accuracy. The model offers a comprehensive analysis of the different capacitances occurring between the electrodes within the device. The simulation of the model shows good agreement with the experimental measurements, confirming the model’s validity. The model is implemented in the Verilog-A hardware description language, with the circuit being subsequently constructed and subjected to simulations via the HSPICE tool. The CNTFET-based inverter exhibits a gain of 7.022 and a delay time of 16.23 ps when operated at a voltage of 1.2 V. Carbon nanotube field-effect transistor ; Carbon nanotube ; Materials science ; Spice ; Quantum capacitance ; Voltage ; Field-effect transistor ; Transistor ; Electronic engineering ; Parametric statistics ; Bipolar junction transistor ; Nanotechnology ; Computer science ; Optoelectronics ; Electrical engineering ; Engineering ; Mathematics Carbon Nanotubes in Composites ; Advancements in Semiconductor Devices and Circuit Design ; Low-power high-performance VLSI design
Authors: Emma C. Regan | Zheyu Lu | Danqing Wang | Yang Zhang | Trithep Devakul | Jacob H. Nie | Zuocheng Zhang | Wenyu Zhao | Kenji Watanabe | Takashi Taniguchi | Sefaattin Tongay | Alex Zettl | Liang Fu | Feng Wang
Source: Nature Communications (article, 2024-11-26)
Field: Materials Science — Materials Chemistry

Spin transport of a doped Mott insulator in moiré heterostructures Moiré superlattices of semiconducting transition metal dichalcogenide heterobilayers are model systems for investigating strongly correlated electronic phenomena. Specifically, WSe<sub>2</sub>/WS<sub>2</sub> moiré superlattices have emerged as a quantum simulator for the two-dimensional extended Hubbard model. Experimental studies of charge transport have revealed correlated Mott insulator and generalized Wigner crystal states, but spin transport of the moiré heterostructure has not yet been sufficiently explored. Here, we use spatially and temporally resolved circular dichroism spectroscopy to directly image the spin transport as a function of carrier doping and temperature in WSe<sub>2</sub>/WS<sub>2</sub> moiré heterostructures. We observe diffusive spin transport at all hole concentrations at 11 Kelvin - including the Mott insulator at one hole per moiré unit cell - where charge transport is strongly suppressed. At elevated temperatures the spin diffusion constant remains unchanged in the Mott insulator state, but it increases significantly at finite doping away from the Mott state. The doping- and temperature-dependent spin transport can be qualitatively understood using a t-J model, where spins can move via the hopping of spin-carrying charges and via the exchange interaction. Condensed matter physics ; Mott insulator ; Heterojunction ; Doping ; Spins ; Spin (aerodynamics) ; Spin diffusion ; Materials science ; Metal–insulator transition ; Superlattice ; Variable-range hopping ; Physics ; Electrical resistivity and conductivity ; Metal ; Quantum mechanics 2D Materials and Applications ; Perovskite Materials and Applications ; Graphene research and applications
Authors: Alexander Stangl | Nicolas Nuns | Caroline Pirovano | Kosova Kreka | Francesco Chiabrera | Albert Tarancón | Mónica Burriel
Source: Small Structures (article, 2024-09-23)
Field: Materials Science — Materials Chemistry

Real‐Time Observation of Oxygen Diffusion in CGO Thin Films Using Spatially Resolved Isotope Exchange Raman Spectroscopy The exploitation of advanced materials for novel energy, health, and computing applications requires deep insight and fundamental understanding of physicochemical mechanisms, such as ionic and electronic conductivity, defect formation processes, and reaction kinetics. Therefore, access to the underlying constants of the functional materials via advanced but accessible and straightforward experimental techniques is key. Herein, a novel, cheap, fast, and widely applicable approach is presented to analyze oxygen tracer diffusion in thin films with unprecedented time resolution based on the novel in situ isotope exchange Raman spectroscopy (IERS) methodology. IERS utilizes the sensitivity of micro‐Raman spectroscopy to changes in the local isotopic composition. In‐plane tracer diffusion gradients are established by partially blocking the exchange at the surface followed by an isotope exchange. The isotope exchange and diffusion processes are followed via consecutive spatial and time‐resolved in situ Raman line scans. These isotopic gradients are analyzed to obtain mass transport coefficients, with an additional time component, not accessible by conventional destructive techniques. Diffusion coefficients of gadolinium‐doped ceria (CGO) thin films are reported within the range of interest for intermediate‐temperature emerging applications and confirm the validity of the measurement procedure and extracted parameters by comparison with the finite‐element method simulations and literature results. Raman spectroscopy ; Diffusion ; Analytical Chemistry (journal) ; Thin film ; Chemistry ; Isotope ; Spectroscopy ; Chemical physics ; Materials science ; Nanotechnology ; Thermodynamics ; Optics ; Nuclear physics Advancements in Solid Oxide Fuel Cells ; Catalytic Processes in Materials Science ; Electronic and Structural Properties of Oxides
Authors: Romain Guibert | Pierre Horgue | Gérald Debenest
Source: SoftwareX (article, 2024-12-26)
Field: Materials Science — Surfaces, Coatings and Films

Micro-continuum modeling of biofilm growth coupled with hydrodynamics in OpenFOAM Biofilm growth is a complex phenomenon that couples species transport and reactions with fluid flow dynamics. Simulating these processes in complex geometries remains challenging due to the different time and space scales, as well as the associated computational cost. biofilmFoam is a toolbox based on OpenFOAM that couples advection–diffusion equations with source terms (related to the reactions involved) with the dynamics of the surrounding fluid. This framework provides an efficient basis for performing reliable simulations on any domain or for building more complex models. Computer science ; Biofilm ; Mechanics ; Physics ; Geology Polymer Surface Interaction Studies ; Surface Modification and Superhydrophobicity ; Bacterial biofilms and quorum sensing
Authors: Chaochao Pan | Gaoyuan Ouyang | Wei Tang | Xubo Liu | Ryan Ott | Ikenna C. Nlebedim | Eunjeong Kim | S. McCall | Alexander A. Baker | Jun Cui
Source: JOM (article, 2024-05-29)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Hot-Roll Fabrication of Anisotropic Nanograin Nd-Fe-B Magnet Magnet ; Coercivity ; Materials science ; Fabrication ; Raw material ; Grain size ; Metallurgy ; Neodymium magnet ; Anisotropy ; Condensed matter physics ; Mechanical engineering ; Optics Magnetic Properties of Alloys ; Magnetic properties of thin films ; Metallic Glasses and Amorphous Alloys
Authors: Qingqing Long | Yuchen Yan | Wentao Cui | Wei Ju | Zhihong Zhu | Yuanchun Zhou | Xuezhi Wang | Meng Xiao
Source:  (article, 2024-10-20)
Field: Materials Science — Materials Chemistry

MOAT: Graph Prompting for 3D Molecular Graphs Molecular property prediction stands as a cornerstone task in AI-driven drug design and discovery, wherein the atoms within a molecule serve as nodes, collectively forming a graph with bonds acting as edges. Given the crucial role of geometric structures in molecular property prediction, the integration of 3D information with various graph learning methods has been explored to enhance prediction performance. Despite the increasing adoption of the "Graph pre-training and fine-tuning" paradigm to refine molecular representations, a significant challenge persists due to the misalignment between pre-training objectives and downstream tasks. Drawing inspiration from prompt tuning techniques in Natural Language Processing (NLP), several graph prompt-based methods have emerged. However, existing approaches tend to overlook the unique properties inherent in molecular graphs. To address this gap, our paper introduces a novel approach named 3D <u>MO</u> lecul <u>A</u> rpromp <u>T</u> (MOAT) designed specifically for geometric molecules. Specifically, we propose atom-level prompts to capture atom distribution, geometry-level prompts tailored for molecular conformers, where different conformations have distinct chemical properties, and task-level prompts to leverage functional group properties. Results on both 3D and 2D downstream tasks demonstrate its ability to successfully bridge the data gap across diverse settings. To the best of our knowledge, this paper is the first attempt to introduce geometric graph-prompting learning for molecules. Computer science ; Graph ; Combinatorics ; Theoretical computer science ; Mathematics Machine Learning in Materials Science ; Advanced Graph Neural Networks ; Graph Theory and Algorithms
Authors: Zahid Raza | Micheal Arockiaraj | Aravindan Maaran | Arul Jeya Shalini
Source: Frontiers in Chemistry (article, 2024-12-20)
Field: Materials Science — Materials Chemistry

A comparative study of topological entropy characterization and graph energy prediction for Marta variants of covalent organic frameworks Covalent organic frameworks are a novel class of porous polymers, notable for their crystalline structure, intricate frameworks, defined pore sizes, and capacity for structural design, synthetic control, and functional customization. This paper provides a comprehensive analysis of graph entropies and hybrid topological descriptors, derived from geometric, harmonic, and Zagreb indices. These descriptors are applied to study two variations of Marta covalent organic frameworks based on contorted hexabenzocoronenes. We also conduct a comparative analysis using scaled entropies, offering refined tools for assessing the intrinsic topologies of these networks. Additionally, these hybrid descriptors are used to develop statistical models for predicting graph energy in higher-dimensional Marta-COFs. Entropy (arrow of time) ; Covalent bond ; Topology (electrical circuits) ; Graph ; Computer science ; Mathematics ; Theoretical computer science ; Chemistry ; Physics ; Thermodynamics ; Combinatorics ; Organic chemistry Covalent Organic Framework Applications ; Metal-Organic Frameworks: Synthesis and Applications ; Luminescence and Fluorescent Materials
Authors: Mohamed R. Eletmany
Source: International Journal of Current Research in Science Engineering & Technology (article, 2024-02-08)
Field: Chemistry — Organic Chemistry

Advancements in Green Chemistry: Microwave-Assisted Synthesis of Poly-Heterocyclic Compounds in Aqueous Media This comprehensive review explores the recent strides made in the field of green chemistry, focusing on the utilization of microwave (MW) irradiation for the synthesis of poly-heterocyclic compounds in aqueous media.The adoption of environmentally benign protocols involving greener alternatives has led to significant reductions in chemical waste and reaction time.The review highlights various methodologies, such as the MW-assisted synthesis of nitrogen-containing heterocycles, cyclic ureas, triazoles, dihydropyrimidinones, oxygen heterocycles, tetrahydropyrans, and heterocyclic hydrazones.The synthesis of diverse heterocyclic structures is accomplished through innovative strategies, including N-alkylation, direct Grignard-type addition, and three-component condensation reactions.The review emphasizes the advantages of these approaches, such as shorter reaction times, higher product yields, and the elimination of hazardous organic solvents.Additionally, the use of recyclable catalysts, such as montmorillonite K10 clay and nano-sized magnesium oxide, contributes to the eco-friendly nature of the methodologies.The incorporation of green synthesis principles, including water-mediated conditions and catalyst recyclability, reflects a commitment to sustainable and efficient synthetic practices.This review provides valuable insights into the ongoing efforts to minimize the environmental footprint of chemical synthesis while advancing the field of heterocyclic compound synthesis. Aqueous medium ; Microwave chemistry ; Green chemistry ; Microwave ; Chemistry ; Aqueous solution ; Nanotechnology ; Organic chemistry ; Materials science ; Microwave irradiation ; Ionic liquid ; Computer science ; Catalysis ; Telecommunications Multicomponent Synthesis of Heterocycles ; Synthesis and biological activity ; Microwave-Assisted Synthesis and Applications