jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Mohammad Azam | Manasa Manasa | T. Zajarniuk | R. Diduszko | Taras Palasyuk | Tomasz Cetner | A. Morawski | Cezariusz Jastrzębski | A. Szewczyk | M. Wierzbicki | Shiv J. Singh
Source: arXiv (Cornell University) (preprint, 2024-12-30)
Field: Materials Science — Electronic, Optical and Magnetic Materials

High-pressure growth effects on the superconducting properties of Sm-based oxypnictide superconductors High-pressure synthesis can be an effective method for improving the sample quality of materials as well as their superconducting properties. In this paper, the synthesis process of F- doped SmFeAsO has been optimized by preparing a series of bulk SmFeAsO0.8F0.2 (Sm1111) using the high gas pressure and high-temperature synthesis (HP-HTS) method, considering various growth parameters like growth pressures (0-1 GPa) and heating time (0.5-2 h). Structural, microstructural, Raman spectroscopic, transport, and magnetic measurements are employed to comprehensively analyze these bulks and derive the conclusive findings. The parent SmFeAsO0.8F0.2 prepared by the conventional synthesis process at ambient pressure (CSP) has a transition temperature (Tc) of around 53-54 K, and the critical current density (Jc) of 103 A/cm2 at 5 K with a small amount of the impurity phases (SmOF and SmAs), consistent with previous reports. Interestingly, all bulks synthesized by HP-HTS have almost the same Tc and Jc as the parent sample. The optimal growth conditions are obtained as 900C, 1 hour, and 0.5 GPa with the sealed Ta-tube, which slightly improved the sample quality and the superconducting properties compared to other bulks grown by HP-HTS. Our study confirms that the existence of the impurity phases in the 1111 family is very robust and cannot be reduced by HP-HTS, leading to only a small variation in the observed superconducting properties of Sm1111 whether prepared by CSP or HP-HTS. This is the first comprehensive investigation of the high-pressure development of Sm1111, which shows distinct behaviour from other families of iron-based superconductors. Superconductivity ; Condensed matter physics ; Physics ; Materials science Iron-based superconductors research ; Rare-earth and actinide compounds ; Intellectual Capital and Performance Analysis
Authors: Ms. A Lalitha Jyothi | Nitla Stanley Ebenezer | Yakobu Gaddepalli | K Prabhash | G.T.N. Veerendra | Durga Prasad M
Source: International Journal for Research in Applied Science and Engineering Technology (article, 2024-05-29)
Field: Materials Science — Surfaces, Coatings and Films

Hydrophobic Coating on Metal Matrix Composites Abstract: The combination of traditional aluminum metal matrix composites (MMCs) with innovative reinforcement materials offers promising avenues for enhancing material properties and expanding application domains. In this study, aluminum matrix composites reinforced with ZrB2 (zirconium diboride) particles were fabricated using a stir casting technique. The addition of ZrB2 to the aluminum matrix aimed to improve mechanical strength, wear resistance, and thermal stability. Following fabrication, the resulting composite specimens were subjected to a surface modification process involving the application of a superhydrophobic coating. The superhydrophobic coating, characterized by its extreme water repellency and self-cleaning properties, was applied to the surface of the aluminum-ZrB2 composites using a spray-coating method. The coating material consisted of a hydrophobic compound integrated with nanostructured particles, engineered to achieve a hierarchical surface morphology that mimics natural superhydrophobic surfaces. The coated specimens were evaluated for their water repellency, contact angle measurements, and durability under various environmental conditions. The results of this study demonstrated that the combination of aluminum metal matrix composites with ZrB2 reinforcement, coupled with the application of a superhydrophobic coating, yielded surfaces with exceptional water-repellent properties. The coated composites exhibited high contact angles and low water adhesion, indicative of their superhydrophobic nature. Furthermore, the durability tests revealed the robustness of the coating against mechanical abrasion and environmental exposure. Overall, the integration of aluminum-ZrB2 composites with a superhydrophobic coating holds significant promise for applications requiring water-resistant surfaces, suchas aerospace components, marine structures, and outdoor equipment. This researchcontributes to advancing the development of multifunctional materials with tailoredsurface properties, paving the way for improved performance and longevity in diverse engineering applications Composite material ; Materials science ; Coating ; Metal ; Matrix (chemical analysis) ; Metallurgy Surface Modification and Superhydrophobicity
Authors: Jordan Rio | Quentin Pessemesse | Michele Cascella | Pierre‐Adrien Payard | Lionel Perrin
Source: ChemRxiv (preprint, 2024-09-24)
Field: Chemistry — Organic Chemistry

Organozinc reagents in solution: insights from ab initio molecular dynamics and X-ray absorption spectroscopy <div> Organozinc reagents play a critical role in synthesis, yet our comprehension of their structure-reactivity relationships is limited by a lack of information about their structures in solution. This study introduces a computational workflow, validated by X-ray absorption spectroscopy, to investigate organozinc reagents in solution. The solvation states of ZnCl 2 , ZnMeCl and ZnMe 2 were explored using ab initio molecular dynamics (metadynamics and Blue Moon sampling) within an explicit solvent cage. The study revealed the existence of various solvation states at room temperature, providing clarity on the previously debated structure of ZnMe 2 in THF solution. These findings were confirmed by nearedge X-ray absorption spectroscopy (XANES) interpreted using time-dependent density functional theory (TD-DFT) calculations. </div> Solvation ; XANES ; Ab initio ; Chemistry ; Metadynamics ; Density functional theory ; X-ray absorption spectroscopy ; Spectroscopy ; Absorption spectroscopy ; Absorption (acoustics) ; Reactivity (psychology) ; Computational chemistry ; Molecular dynamics ; Chemical physics ; Ab initio quantum chemistry methods ; Physical chemistry ; Materials science ; Molecule ; Physics ; Organic chemistry ; Quantum mechanics Coordination Chemistry and Organometallics ; Molecular Junctions and Nanostructures ; Inorganic and Organometallic Chemistry
Authors: Patrik Török | József Kaizer
Source: Molecules (article, 2024-08-13)
Field: Chemistry — Inorganic Chemistry

Effect of Substituted Pyridine Co-Ligands and (Diacetoxyiodo)benzene Oxidants on the Fe(III)-OIPh-Mediated Triphenylmethane Hydroxylation Reaction Iodosilarene derivatives (PhIO, PhI(OAc)<sub>2</sub>) constitute an important class of oxygen atom transfer reagents in organic synthesis and are often used together with iron-based catalysts. Since the factors controlling the ability of iron centers to catalyze alkane hydroxylation are not yet fully understood, the aim of this report is to develop bioinspired non-heme iron catalysts in combination with PhI(OAc)<sub>2</sub>, which are suitable for performing C-H activation. Overall, this study provides insight into the iron-based ([Fe<sup>II</sup>(PBI)<sub>3</sub>(CF<sub>3</sub>SO<sub>3</sub>)<sub>2</sub>] (<b>1</b>), where PBI = 2-(2-pyridyl)benzimidazole) catalytic and stoichiometric hydroxylation of triphenylmethane using PhI(OAc)<sub>2</sub>, highlighting the importance of reaction conditions including the effect of the co-ligands (<i>para</i>-substituted pyridines) and oxidants (<i>para</i>-substituted iodosylbenzene diacetates) on product yields and reaction kinetics. A number of mechanistic studies have been carried out on the mechanism of triphenylmethane hydroxylation, including C-H activation, supporting the reactive intermediate, and investigating the effects of equatorial co-ligands and coordinated oxidants. Strong evidence for the electrophilic nature of the reaction was observed based on competitive experiments, which included a Hammett correlation between the relative reaction rate (log<i>k</i><sub>rel</sub>) and the σ<sub>p</sub> (4R-Py and 4R'-PhI(OAc)<sub>2</sub>) parameters in both stoichiometric (ρ = +0.87 and +0.92) and catalytic (ρ = +0.97 and +0.77) reactions. The presence of [(PBI)<sub>2</sub>(4R-Py)Fe<sup>III</sup>OIPh-4R']<sup>3+</sup> intermediates, as well as the effect of co-ligands and coordinated oxidants, was supported by their spectral (UV-visible) and redox properties. It has been proven that the electrophilic nature of iron(III)-iodozilarene complexes is crucial in the oxidation reaction of triphenylmethane. The hydroxylation rates showed a linear correlation with the Fe<sup>III</sup>/Fe<sup>II</sup> redox potentials (in the range of -350 mV and -524 mV), which suggests that the Lewis acidity and redox properties of the metal centers greatly influence the reactivity of the reactive intermediates. Chemistry ; Hydroxylation ; Triphenylmethane ; Catalysis ; Benzimidazole ; Electrophile ; Medicinal chemistry ; Pyridine ; Reactive intermediate ; Catalytic cycle ; Stoichiometry ; Thioanisole ; Photochemistry ; Stereochemistry ; Organic chemistry ; Enzyme Metal-Catalyzed Oxygenation Mechanisms ; Porphyrin and Phthalocyanine Chemistry ; Oxidative Organic Chemistry Reactions
Authors: Thananya Siriwas | Skulrat Pichaiyut | Markus Susoff | Svea Petersen | Charoen Nakason
Source: Research Square (preprint, 2024-01-24)
Field: Materials Science — Polymers and Plastics

Optimizing the Thermomechanical and Thermal Performance of Epoxidized Natural Rubber Hybrid Nanocomposites Using Graphene and Carbon Nanotubes Carbon nanotube ; Natural rubber ; Materials science ; Graphene ; Nanocomposite ; Composite material ; Thermal ; Carbon fibers ; Composite number ; Nanotechnology Polymer Nanocomposites and Properties ; Tribology and Wear Analysis ; Carbon Nanotubes in Composites
Authors: I. Garduño | Cecilio Santos Hernández | Flor Cecilia Sánchez Vargas | María Isabel Reyes-Valderrama | Ventura Rodríguez-Lugo | M. Estrada
Source: Tópicos de Investigación en Ciencias de la Tierra y Materiales (article, 2024-10-05)
Field: Materials Science — Biomaterials

Proceso de Impresión por Inyección Piezoeléctrica de Tintas de Ag y MoO3, Enfocado a su Aplicación en Celdas Solares Orgánicas Recientemente, la tecnología de impresión ha ofrecido una herramienta fundamental para el desarrollo de celdas solares fabricadas con materiales sustentables y sobre sustratos flexibles. Sin embargo, persisten diferentes retos por superar para mejorar el desempeño de estos dispositivos opto-electrónicos, como el control en la uniformidad del área impresa mediante los diferentes factores que influyen en el proceso. Por tales motivos, en este trabajo se estableció un proceso básico para la impresión por Goteo-Sobre-Demanda (DoD) de tintas comerciales de plata (Ag) y de trióxido de molibdeno (MoO3), formando directamente patrones con diferentes resoluciones. Esto se consiguió al aplicar una configuración del equipo de impresión que permite un modo DoD continuo, uniforme y repetible, además de las condiciones apropiadas durante el proceso y posterior a éste, y las caracterizaciones de algunas de sus propiedades. Derivado de este estudio, se dispone de una secuencia tecnológica general para mejorar los patrones impresos de Ag y MoO3 y su potencial aplicación en celdas solares orgánicas. Humanities ; Physics ; Philosophy Electrospun Nanofibers in Biomedical Applications ; Conducting polymers and applications
Authors: Michaël Lobet | Florian Gillissen | Nicolas DeMoor | Jennifer Dewalque | Pierre Colson | Rudi Cloots | Anthony Maho | Luc Henrard
Source: arXiv (Cornell University) (preprint, 2024-06-04)
Field: Materials Science — Polymers and Plastics

Plasmonic properties of electrochromic doped metal oxides investigated through Kubelka Munk formalism Materials with broadband tunable optical properties are looked for in smart windows applications. Doped metal oxides presenting dual band visible (VIS) near infrared (NIR) electrochromic properties can be used for solving such a challenge, and their accurate optical characterization is therefore of prime importance. Kubelka Munk model is a state of the art way to optically quantify the absorption properties of materials and is occasionally applied to plasmonic materials, even if great care should be taken to meet the formalism hypotheses. In the present work, Kubelka Munk theory is discussed in the context of particles of indium tin oxide and molybdenum tungsten oxide formulations that are used as single NIR and both VIS and NIR active advanced electrochromic materials, respectively. An analytical model is derived for particles of much smaller dimensions than the incident wavelength and is experimentally verified. A dilution method is applied to verify the plasmonic characteristics of the particles. This study is key for efficient characterization of optical properties of metal oxides, and plasmonic materials in general, from diffuse reflectance measurements. Electrochromism ; Doping ; Formalism (music) ; Plasmon ; Materials science ; Metal ; Condensed matter physics ; Optoelectronics ; Physics ; Quantum mechanics ; Metallurgy ; Electrode Transition Metal Oxide Nanomaterials ; Pigment Synthesis and Properties
Authors: Ming-Kai Wei | Ze‐Xin Zhang | Mingyan Ding | Michael C. Willis
Source: Angewandte Chemie (article, 2024-10-11)
Field: Chemistry — Organic Chemistry

Friedel–Crafts Reactivity with Sulfondiimidoyl Fluorides for the Synthesis of Heteroaryl Sulfondiimines Abstract Sulfur functional groups are ubiquitous in molecules used in the pharmaceutical and agrochemical industries, and within these collections sulfones hold a prominent position. The double aza‐analogues of sulfones, sulfondiimines, offer significant potential in discovery chemistry but to date their applications have been limited by the lack of convenient synthetic routes. The existing methods mainly rely on imination of low‐valent‐sulfur intermediates, or the combination of pre‐formed organometallic reagents and electrophilic S(VI)‐functionalities. Herein, we describe a Friedel–Crafts‐type reaction of sulfondiimidoyl fluorides with (hetero)aryls. This new SuFEx reactivity benefits from broad functional group tolerance, mild reaction conditions, and does not require the use of pre‐formed organometallic reagents. The efficient use of unprotected indoles and pyrroles, as well as furan, thiophene and carbocyclic aromatics, further demonstrates the advantages of these reactions. We show that the reactivity of the sulfondiimidoyl fluorides can be tuned by switching the N ‐substituents, allowing an expansion of the range of coupling partners. The utility of the transformation is exemplified by the synthesis of the sulfondiimine analogue of the HIV‐I reverse transcriptase‐inhibitor L‐737,126. Friedel–Crafts reaction ; Reactivity (psychology) ; Chemistry ; Combinatorial chemistry ; Organic chemistry ; Catalysis ; Medicine Synthesis and Catalytic Reactions ; Synthesis and Biological Evaluation ; Phenothiazines and Benzothiazines Synthesis and Activities
Authors: Muhammad Umar Draz | Amina | Saad Ullah Bhatti | Asim Yaqub | Ali Turab Jafry | Huma Ajab
Source: Springer Link (Chiba Institute of Technology) (article, 2024-06-25)
Field: Chemistry — Electrochemistry

Development in Heavy Metal Ions Detection: Antimony-Hydroxyapatite Modified Electrodes Coupled with Square Wave Anodic Stripping Voltammetry The occurrence of heavy metal ions in environmental matrices presents serious risks to human health and ecosystems. An electrochemical sensor for the simultaneous detection of lead (Pb) and cadmium (Cd) ions in aqueous samples is presented in this study. The sensor was optimized through material composition, electrolyte, deposition, and electrochemical parameters using a modified carbon paste electrode (CPE) comprising hydroxyapatite (HAp) and antimony (Sb). Calibration studies showed high sensitivity (0.574 ± 0.32 ppb) and strong linearity (R2 = 0.993) for Pb detection. Repeated studies showed that the minimum standard deviation (RSD) was ±3.73%, confirming the reliability of the results. Real sample analysis of tap water with the developed method had less than 5% deviation in results as compared to results obtained from atomic absorption spectrometry (AAS). Furthermore, promising results were obtained from simultaneous detection of Pb(II) and Cd(II) ions, thus the sensor showed reliability for practical applications. Anodic stripping voltammetry ; Analytical Chemistry (journal) ; Stripping (fiber) ; Cadmium ; Metal ions in aqueous solution ; Electrode ; Electrochemical gas sensor ; Electrochemistry ; Calibration Electrochemical Analysis and Applications ; Analytical Chemistry and Sensors ; Dye analysis and toxicity
Authors: Zamzuri Zamzuri
Source: Journal of Advanced Research in Applied Sciences and Engineering Technology (article, 2024-12-24)
Field: Chemistry — Organic Chemistry

westac Cu2O stands out as a promising semiconductor material for solar energy conversion, primarily due to its exceptional light-absorbing qualities and its widespread availability. However, its efficiency is somewhat hindered by its relatively low carrier mobility and a limited absorption band for carriers. The introduction of magnesium (Mg) doping into Cu2O has emerged as a potential means to enhance its morphology, optical characteristics, and electrical properties, making it an intriguing avenue for exploration. To fabricate the Mg-doped Cu2O layers, an electrodeposition process was employed on an Indium Tin Oxide (ITO) substrate. The resulting films were then subjected to characterization using Field Emission Scanning Electron Microscopy (FESEM), Ultraviolet-Visible Spectroscopy (UV-Vis), and HALL Effect Measurement, focusing on their morphology, optical properties, and electrical behaviors. Notably, the concentration of magnesium played a significant role in shaping the properties of the Cu2O layer. The fabrication process extended up to a dopant concentration of 0.3 M for both undoped Cu2O and Mg-doped Cu2O layers, leading to morphological alterations. Specifically, the grain size increased with varying dopant concentrations, but it became smaller and more compact after doping with 0.3 M Mg. The average absorbance of visible light for both undoped and Mg-doped Cu2O layers fell within the range of 1~2 au. Intriguingly, a doping level of 0.3 M Mg led to the simultaneous achievement of high carrier mobility (29.98 cm2/Vs), low bulk carrier concentration (2.3.928 x 1021 cm-3), and high resistivity (5.3 x 10-5 Ωcm) in the Cu2O material. Additionally, Cu2O/ITO thin films exhibiting rectifying characteristics were successfully fabricated, confirming the semiconductor nature of the deposited p-type Cu2O layer. The primary objective of this study was to synthesize Cu2O layers doped with varying concentrations of Mg and thoroughly characterize their morphology, optical attributes, and electrical behaviors through the electrodeposition method. The study findings and implications were extensively discussed. Philosophy Chemistry and Stereochemistry Studies
Authors: Mannava Laharika Choudary | Medidi Srinivas | Bula Udaya Kumari
Source: Journal of Drug Delivery and Therapeutics (article, 2024-07-13)
Field: Chemistry — Analytical Chemistry

Method Development and Validation for Estimation of Etifoxine in Capsule Dosage Form by Using RP-HPLC/UV A RP-HPLC/UV method was developed and validated to quantify the etifoxine in capsule dosage form. The chromatographic separation was carried out using a Hypersil ODS C18 column (250×4.6 mm, 5 μm) with a mobile phase consisting of an ammonium acetate buffer: acetonitrile in a volumetric ratio of 40:60%. The UV wavelength chosen for detection was at 255 nm. The flow rate was set at 1 ml/min. The retention time for etifoxine was determined to be 2.074 min. Linearity was detected within the concentration range of 7.5-45 μg/mL for etifoxine. The approach has been confirmed to be linear, accurate, precise, robust, and has established limits of detection and quantitation. The established procedure was uncomplicated, cost-effective, and suitable for the routine analysis of etifoxine in capsule dosage form. Chromatography ; Capsule ; Acetonitrile ; High-performance liquid chromatography ; Ammonium acetate ; Dosage form ; Chemistry ; Linearity Analytical Methods in Pharmaceuticals ; Analytical Chemistry and Chromatography ; Antibiotics Pharmacokinetics and Efficacy
Authors: Jackson Campbell | Yifan Wang
Source: Methods in enzymology on CD-ROM/Methods in enzymology (article, 2024-01-01)
Field: Chemistry — Inorganic Chemistry

Observing extradiol dioxygenases in action through a crystalline lens Dioxygenase ; Enzyme ; Chemistry ; Heme ; Biochemistry ; Biosynthesis ; Oxidoreductase ; Stereochemistry ; Catalytic cycle ; Nicotinamide adenine dinucleotide ; Transferase ; Electron paramagnetic resonance ; NAD+ kinase Metal-Catalyzed Oxygenation Mechanisms ; Heme Oxygenase-1 and Carbon Monoxide ; Microbial metabolism and enzyme function
Authors: Shu-Jen Wang | Sebastian Hutsch | Felix Talnack | Marielle Deconinck | Shi‐Yu Huang | Zongbao Zhang | Hans Kleemann | Yana Vaynzof | Stefan C. B. Mannsfeld | Frank Ortmann | Karl Leo
Source: arXiv (Cornell University) (preprint, 2024-04-17)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Band Structure Engineering in Highly Crystalline Organic Semiconductors Blending of semiconductors for controlling the energy levels (band structure engineering) is an important technique, in particular, for optoelectronic applications. The underlying physics is the delocalized Bloch states, which average over the potential landscape of the blend. For organic semiconductors, it has been shown that two quite different effects, the dielectric constant and electrostatic interaction between molecules, can be used to tune the energy gap and ionization energy of disordered and weakly crystalline organic semiconductor blends. It is so far not known whether the electronic delocalization in organic crystals with large bandwidths can contribute to the energy structure engineering of the blend in a way similar to that in inorganic semiconductors. Here, we investigate the growth of highly ordered organic thin-film blends with a similar chemical structure and show the effect of band structure engineering by spectroscopic methods. We rationalize the experimental results with comprehensive theoretical simulations, showing that the delocalization is a significant effect. Our work paves the way for engineering the band structure of highly ordered organic semiconductor thin films that can be tailored for the desired optoelectronic device application. Organic semiconductor ; Semiconductor ; Materials science ; Electronic band structure ; Engineering physics ; Engineering ; Optoelectronics ; Physics ; Condensed matter physics Nonlinear Optical Materials Research ; Organic Electronics and Photovoltaics ; Machine Learning in Materials Science