jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Evangelia Tarani | K. Chrissafis
Source: International Journal of Environmental Science and Technology (article, 2023-10-27)
Field: Materials Science — Polymers and Plastics

A comparative study of drinking straws made from natural resources: structural and morphological characterization Abstract This study focuses on identifying a high-value material using low-cost raw resources by comparing wheat straw varieties collected in Greece with other commercial straws made of reed, bamboo, paper, and bioplastic. The structural characteristics, water absorption behavior, and morphological properties of the straws were analyzed using X-ray diffraction, water immersion tests, and scanning electron microscopy. The thermal degradation was investigated using thermogravimetric analysis. The results suggest that the wheat straws exhibit a significant degree of crystallinity, with the Staramaki K1 straw exhibiting the highest crystallinity of all the straws analyzed. The mass of wheat straws increased after immersion in water, coca-cola, and fresh orange juice in contrast to the mass of bioplastic and bamboo straws, which remained constant. The surface examination revealed modifications to the strawsʼ outer and inner surfaces after immersion in the various solutions. To variable degrees, pores, cracks, peeling material, lighter patches, and anomalies were seen. The presence of a highly crystalline structure can increase the strawʼs hardness and reduce its water absorption, making it more resistant to changes brought about by the solutions. So, the Staramaki K1 wheat straw exhibits favorable properties, including high crystallinity, lower water absorption, and thermal stability, making it a promising candidate for replacing conventional plastic drinking straws. Crystallinity ; Straw ; Absorption of water ; Thermogravimetric analysis ; Materials science ; Bamboo ; Scanning electron microscope ; Composite material ; Dehydration ; Immersion (mathematics) ; Chemistry ; Agronomy ; Mathematics ; Biology Natural Fiber Reinforced Composites ; Advanced Cellulose Research Studies ; Bamboo properties and applications
Authors: Yin Shi | Venkatraman Gopalan | Long‐Qing Chen
Source: Physical review. B./Physical review. B (article, 2023-05-15)
Field: Materials Science — Polymers and Plastics

Phase-field model of coupled insulator-metal transitions and oxygen vacancy redox reactions A predominant ubiquitous feature of strongly correlated oxides is the possible presence of oxygen vacancies, which has recently been shown to have profound effects on their electronic phase transitions. Here, we formulate a comprehensive phase-field model of intercoupled insulator-metal transitions and oxygen vacancy redox reactions, taking into account the valence electron state of oxygen vacancies. We use the model to study the voltage self-oscillation phenomenon in a prototypical strongly correlated oxide, ${\text{VO}}_{\text{2}}$, and discover the mutual activation of the insulator-metal transition and oxygen vacancy redox reactions leading to systematic enhancement of the oscillation frequency. The established methodology and the mutual activation mechanism are generally applicable to understanding any insulator-metal transition dynamics in oxygen-deficient correlated oxides and improving the performance of voltage self-oscillation-based artificial neurons. Redox ; Oscillation (cell signaling) ; Oxygen ; Chemical physics ; Phase transition ; Valence (chemistry) ; Condensed matter physics ; Metal ; Materials science ; Oxide ; Chemistry ; Physics ; Inorganic chemistry Transition Metal Oxide Nanomaterials ; Advanced Memory and Neural Computing ; Gas Sensing Nanomaterials and Sensors
Authors: Dongbo Zhao | Xin He | Paul W. Ayers | Shubin Liu
Source: Preprints.org (preprint, 2023-02-07)
Field: Chemistry — Physical and Theoretical Chemistry

Excited-State Polarizabilities: A Combined Density Functional Theory and Information-Theoretic Approach Study Accurate and efficient determination of excited-state polarizabilities (&amp;alpha;) is an open problem both experimentally and computationally. Following our previous work, [Phys. Chem. Chem. Phys. 2023, 25, 2131&amp;minus;2141], where one can employ simple ground-state density-based functions from the information-theoretic approach (ITA) to accurately and efficiently predict the macromolecular polarizabilities, we aim to predict the lowest excited-state polarizabilities in this work. The philosophy is to use density-based functions to depict the excited-state polarizabilities. As a proof-of-principle application, employing 2-(2&amp;prime;-hydroxyphenyl)benzimidazole and its derivatives as model systems, we have verified that either with the ground-state (S0) or excited-state (S1) densities as input, ITA quantities can be strongly correlated with the excited-state polarizabilities. When the transition densities are considered, both S0 and S1 polarizabilities are in good relationships with some ITA quantities. Furthermore, excitation and emission energies can be predicted based on multivariant linear regression equations of ITA quantities. Excited state ; Density functional theory ; Excitation ; Ground state ; Work (physics) ; Atomic physics ; Chemistry ; Time-dependent density functional theory ; Computational chemistry ; Statistical physics ; Physics ; Quantum mechanics Photochemistry and Electron Transfer Studies ; Molecular Junctions and Nanostructures ; Free Radicals and Antioxidants
Authors: Alfredo Fiorentino | Enrico Drigo | Stefano Baroni | Paolo Pegolo
Source: arXiv (Cornell University) (preprint, 2023-07-14)
Field: Materials Science — Materials Chemistry

Unearthing the foundational role of anharmonicity in heat transport in glasses The time-honored Allen-Feldman theory of heat transport in glasses is generally assumed to predict a finite value for the thermal conductivity, even if it neglects the anharmonic broadening of vibrational normal modes. We demonstrate that the harmonic approximation predicts that the bulk lattice thermal conductivity of harmonic solids inevitably diverges at any temperature, irrespective of configurational disorder, and that its ability to represent the heat-transport properties observed experimentally in most glasses is implicitly due to finite-size effects. Our theoretical analysis is thoroughly benchmarked against careful numerical simulations. Our findings thus reveal that a proper account of anharmonic effects is indispensable to predict a finite value for the bulk thermal conductivity in any solid material, be it crystalline or glassy. Anharmonicity ; Thermal conductivity ; Condensed matter physics ; Lattice (music) ; Harmonic ; Thermal ; Thermal conduction ; Materials science ; Conductivity ; Specific heat ; Statistical physics ; Thermodynamics ; Physics ; Quantum mechanics Thermal properties of materials ; Material Dynamics and Properties ; Thermography and Photoacoustic Techniques
Authors: De‐Shin Liu | Po-Chun Wen | Zhen-Wei Zhuang | Yung-Ching Chao | Pei‐Chen Huang
Source: Journal of Mechanics (article, 2023-01-01)
Field: Materials Science — Materials Chemistry

Temperature-dependence mechanical characteristics investigation of Cu wire and corresponding high strain rate plasticity behaviors enabled by Johnson–Cook constitutive model Abstract The temperature-dependence mechanical characteristics of 4N Cu wire with 25, 30 and 38 μm diameters are investigated via the utilization of micro-tensile tests. Measured data revealed that the concerned mechanical characteristics, Young's modulus and yield stresses, are significantly degraded under high testing temperature, and the variation of aforementioned characteristics degradation are almost linear proportional to the temperature increment. Trapezoidal and standard triangle loop formation of Cu wire are simulated based on the finite element method, the simulated looping profiles of Cu wires are compared to the Au wires and the Cu wire is regarded as the improved solution for the high loop height wire formation. Moreover, the Johnson–Cook constitutive model is utilized to describe the plasticity of Cu wire in accordance with the experimental data under different temperature levels. Accordingly, the comprehensive mechanical characteristics’ investigation of 4N Cu wire are systemically demonstrated and explored. Materials science ; Plasticity ; Constitutive equation ; Modulus ; Composite material ; Finite element method ; Ultimate tensile strength ; Wire drawing ; Strain (injury) ; Loop (graph theory) ; Strain rate ; Thermodynamics Microstructure and mechanical properties ; Advanced Surface Polishing Techniques ; Metal and Thin Film Mechanics
Authors: Sufen Wei | Yi Liu | Qianqian Shi | Tinglin He | Feng Shi | Ming-kwei Lee
Source: Coatings (article, 2023-08-25)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Further Characterization of the Polycrystalline p-Type β-Ga2O3 Films Grown through the Thermal Oxidation of GaN at 1000 to 1100 °C in a N2O Atmosphere The development of good-conductivity p-type β-Ga2O3 is crucial for the realization of its devices and applications. In this study, nitrogen-doped p-type β-Ga2O3 films with the characteristics of enhanced conductivity were fabricated through the thermal oxidation of GaN in a N2O atmosphere. To obtain insights into the underlying mechanism of the thermally activated transformation process, additional measurements of the oxidized films were performed at temperatures of 1000, 1050, and 1100 °C. Room-temperature photoluminescence (PL) spectra showed a moderate ultraviolet emission peak at 246 nm, confirming the generation of gallium oxide with a band gap of approximately 5.0 eV. The characteristics of polycrystalline and anisotropic growth were confirmed via normalized X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and selected-area electron diffraction (SAED) patterns. The amount of incorporated nitrogen was analyzed via secondary ion mass spectrometry (SIMS) to examine the effects of oxidation temperature. Furthermore, the ionization energy of the acceptor in the films oxidized at 1000, 1050, and 1100 °C was calculated and analyzed using temperature-dependent Hall test results. The results indicated that nitrogen doping played a significant role in determining p-type electrical properties. The activation energy of polycrystalline β-Ga2O3, prepared via the thermal oxidation of GaN in the N2O atmosphere, was estimated to be 147.175 kJ·mol−1 using an Arrhenius plot. This value was significantly lower than that obtained via both the dry and wet oxidation of GaN under O2 ambient conditions, thus confirming the higher efficiency of the thermal oxidation of GaN in a N2O atmosphere. Crystallite ; Analytical Chemistry (journal) ; Materials science ; High-resolution transmission electron microscopy ; Photoluminescence ; Band gap ; Selected area diffraction ; Activation energy ; Thermal oxidation ; Oxide ; Transmission electron microscopy ; Chemistry ; Nanotechnology ; Physical chemistry ; Optoelectronics ; Metallurgy Ga2O3 and related materials ; ZnO doping and properties ; Advanced Photocatalysis Techniques
Authors: Yasutomo Otake | Kotaro Matsuyama | Takahiro Umemoto | Takashi Onoda
Source: IEEJ Transactions on Electrical and Electronic Engineering (article, 2023-11-21)
Field: Materials Science — Materials Chemistry

Estimation of the Degradation of Epoxy Resin due to Void Discharge using Weighted<scp>SVM</scp>and Partial Discharge Characteristics The performance and reliability of power apparatus are affected by the degradation of electrical insulation, often caused by voids in resin‐molded components. To address this issue, we investigated the use of machine learning to estimate the degree of degradation due to void discharges in epoxy resin. We prepared samples with artificial void defects and collected partial discharge data up to the dielectric breakdown, applying long‐term AC voltage. Utilizing this data, a machine learning model was developed to estimate degradation levels. The results showed that the accuracy was 55% and the false estimation rate which underestimates the degradation level was as high as 31%, which was a significant problem for practical use. Therefore, for regions of data that were difficult to classify, we constructed a weighted SVM model that predicted higher levels of degradation by weighting the data according to their degradation labels. With this approach, the accuracy remained at 57%, but the rate of underestimation of the degree of degradation was reduced to only 4%. Consequently, we were able to develop an effective estimation model that is practical for the maintenance of power apparatus. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. Partial discharge ; Degradation (telecommunications) ; Void (composites) ; Epoxy ; Support vector machine ; Weighting ; Computer science ; Reliability (semiconductor) ; Materials science ; Voltage ; Power (physics) ; Reliability engineering ; Artificial intelligence ; Composite material ; Engineering ; Electrical engineering ; Acoustics ; Physics High voltage insulation and dielectric phenomena ; Electrostatic Discharge in Electronics ; Infrastructure Maintenance and Monitoring
Authors: Š. Michalik | Zuzana Molčanová | Michaela Šulíková | Katarína Kušnírová | P. Jóvári | Jacques Darpentigny | Karel Saksl
Source: Materials (article, 2023-03-14)
Field: Materials Science — Biomaterials

Structure and Physical Properties of Mg93−xZnxCa7 Metallic Glasses The Mg-Zn-Ca system has previously been proposed as the most suitable biodegradable candidate for biomedical applications. In this work, a series of ribbon specimens was fabricated using a melt-spinning technique to explore the glass-forming ability of the Mg-Zn-Ca system along the concentration line of 7 at.% of calcium. A glassy state is confirmed for Mg<sub>50</sub>Zn<sub>43</sub>Ca<sub>7</sub>, Mg<sub>60</sub>Zn<sub>33</sub>Ca<sub>7</sub>, and Mg<sub>70</sub>Zn<sub>23</sub>Ca<sub>7</sub>. Those samples were characterised by standard methods to determine their mass density, hardness, elastic modulus, and crystallisation temperatures during devitrification. Their amorphous structure is described by means of pair distribution functions obtained by high-energy X-ray and neutron diffraction (HEXRD and ND) measurements performed at large-scale facilities. The contributions of pairs Mg-Mg, Mg-Zn, and Zn-Zn were identified. In addition, a transformation process from an amorphous to crystalline structure is followed in situ by HEXRD for Mg<sub>60</sub>Zn<sub>33</sub>Ca<sub>7</sub> and Mg<sub>50</sub>Zn<sub>43</sub>Ca<sub>7</sub>. Intermetallic compounds IM1 and IM3 and hcp-Mg phase are proposed to be formed in multiple crystallisation eventss. Materials science ; Devitrification ; Crystallization ; Amorphous metal ; Intermetallic ; Melt spinning ; Amorphous solid ; Phase (matter) ; Analytical Chemistry (journal) ; Crystallography ; Chemical engineering ; Composite material ; Metallurgy ; Spinning ; Alloy ; Chemistry Magnesium Alloys: Properties and Applications ; Metallic Glasses and Amorphous Alloys ; Aluminum Alloys Composites Properties
Authors: Hannu Häkkinen | Sami Malola | María Francisca Matus
Source: ChemRxiv (preprint, 2023-05-24)
Field: Materials Science — Materials Chemistry

Theoretical Analysis of the Electronic Structure and Optical Properties of DNA-Stabilized Silver Cluster Ag16Cl2 in Aqueous Solvent DNA-stabilized silver nanoclusters with 10 to 30 silver atoms are by construction ideal candidates for biocompatible bright fluorescent emitters but their electronic structure is not well understood. Here, using density functional theory (DFT), we analyze the ground-state electronic structure and optical absorption of a bright NIR-emitting cluster Ag16Cl2 which is stabilized by two DNA strands of 9-base sequence 5’-CACCTAGCG-3’ and whose atomic structure was very recently confirmed to have two chlorides bound to the silver core. We are able to (i) unambiguously assign the charge of this cluster in aqueous solvent, (ii) analyze the details of silver–DNA interactions and their effect on the cluster charge, (iii) analyze the character of low-energy optical absorption peaks and the involved electron orbitals and make a first assessment on circular dichroism, and (iv) evaluate the suitability of various DFT exchange-correlation functionals via benchmarking to experimental optical data. This work lays out a baseline for all future theoretical work to understand the electronic, chiroptical and fluorescence properties of these fascinating bio-compatible nanostructures. Nanoclusters ; Cluster (spacecraft) ; Density functional theory ; Electronic structure ; Chemistry ; Superatom ; Circular dichroism ; Absorption (acoustics) ; Chemical physics ; Materials science ; Absorption spectroscopy ; Crystallography ; Nanotechnology ; Computational chemistry ; Physics Nanocluster Synthesis and Applications ; Pharmacological Effects and Toxicity Studies
Authors: Ramendra Pati Pandey | Ruby Dhiman | Nancy Bazad | Riya Mukerjee | Jasmina Vidić | Élcio Leal | V. Samuel Raj | Chung-Ming Chang
Source: Preprints.org (preprint, 2023-12-09)
Field: Materials Science — Biomaterials

Enhancing Breast Cancer Therapy: Nanocarrier-Based Targeted Drug Delivery Breast cancer (BC) is one of the most common types of cancer in women. Triple-negative breast cancer (TNBC), characterized by the absence of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), exhibits a highly aggressive phenotype with increased metastasis and resistance to conventional treatments. Nanocarrier technology is consistently employed to overcome limitations associated with traditional breast cancer therapy. The targeted drug delivery approach using nanocarriers enhances bioavailability, prolongs circulation, and facilitates effective drug accumulation at the tumor site through active or passive targeting. Currently, the FDA has approved a few nanocarrier systems, and numerous nano formulations are undergoing preclinical and clinical development for breast cancer targeting. Common nanocarrier types include polymeric micelles, microemulsions, magnetic microemulsions, liposomes, dendrimers, carbon nanotubes, and magnetic nanoparticles (NPs). This review extensively explores the targeting potential of nanocarriers in breast cancer. This study will provide a concise summary of current advances in treatment of breast cancer and diagnostics. Nanocarriers ; Breast cancer ; Drug delivery ; Targeted drug delivery ; Medicine ; Cancer ; Targeted therapy ; Drug ; Pharmacology ; Cancer research ; Nanotechnology ; Internal medicine ; Materials science Nanoparticle-Based Drug Delivery ; Cancer Research and Treatment ; Graphene and Nanomaterials Applications
Authors: Mariah Batool | Andres O. Godoy | Martin Birnbach | Dario R. Dekel | Jasna Janković
Source: Journal of The Electrochemical Society (article, 2023-05-01)
Field: Chemistry — Analytical Chemistry

Evaluation of Semi-Automatic Compositional and Microstructural Analysis of Energy Dispersive Spectroscopy (EDS) Maps via a Python-Based Image and Data Processing Framework for Fuel Cell Applications Computer-aided data acquisition, analysis, and interpretation are rapidly gaining traction in numerous facets of research. One of the subsets of this field, image processing, is most often implemented for post-processing material microstructural characterization data to understand better and predict materials’ features, properties, and behaviors at multiple scales. However, to tackle the ambiguity of multi-component materials analysis, spectral data can be used in combination with image processing. The current study introduces a novel Python-based image and data processing method for in-depth analysis of energy dispersive spectroscopy (EDS) elemental maps to analyze multi-component agglomerate size distribution, the average area of each component, and their overlap. The framework developed in this study is applied to examine the interaction of Cerium Oxide (CeO x ) and Palladium (Pd) particles in the membrane electrode assembly (MEA) of an Anion-Exchange Membrane Fuel Cell (AEMFC) and to investigate if this approach can be correlated to cell performance. The study also performs a sensitivity analysis of several parameters and their effect on the computed results. The developed framework is a promising method for semi-automatic data processing and can be further advanced towards a fully automatic analysis of similar data types in the field of clean energy materials and broader. Python (programming language) ; Image processing ; Computer science ; Solid oxide fuel cell ; Data processing ; Materials science ; Computational science ; Artificial intelligence ; Chemistry ; Electrode ; Image (mathematics) Spectroscopy and Chemometric Analyses ; Electrochemical Analysis and Applications ; Machine Learning in Materials Science
Authors: Saikiran Motati | Ramya Motati | Trisha Kandi | William E. Acree
Source: Liquids (article, 2023-10-02)
Field: Materials Science — Materials Chemistry

Abraham Model Descriptors for Vitamin K4: Prediction of Solution, Biological and Thermodynamic Properties Spectrophotometric measurements were used to determine the mole fraction solubilities of vitamin K4 dissolved in cyclohexane, methylcyclohexane, 1-heptanol, 2-butanol, 2-pentanol, 2-methyl-1-butanol, 4-methyl-2-pentanol, and cyclopentanol at 298.15 K. Results from our experimental measurements, combined with the published solubility data, are used to calculate the solute descriptors of the vitamin K4 solute. The calculated solute descriptors describe the observed solubility data to within an overall standard deviation of 0.110 log units. The calculated solute descriptors were also used to estimate the several blood-to-rat tissue partition coefficients of vitamin K4, as well as the equilibrium vapor pressure above the solid vitamin at 298 K, and the vitamin’s enthalpy of solvation in both water and in 1,4-dioxane organic mono-solvent. Chemistry ; Solubility ; Solvation ; Enthalpy ; Vapor pressure ; Partition coefficient ; Thermodynamics ; Cyclohexane ; Activity coefficient ; Solvent ; Vitamin ; Methylcyclohexane ; Mole fraction ; Chromatography ; Physical chemistry ; Organic chemistry ; Aqueous solution ; Biochemistry Crystallization and Solubility Studies ; Pharmacological Effects of Natural Compounds