jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Emma Baubiat | Nguyen Huy Hoang Vo | Sandra Olivero | Véronique Michelet | Romain Melot
Source: Angewandte Chemie International Edition (article, 2025-07-30)
Field: Chemistry — Organic Chemistry

An Electrochemical Study of Key Catalytically Active Gold Complexes Gold catalysis has long been dominated by the ability of gold(I) to activate unsaturated systems as a carbophilic Lewis acid. However, recent advances have highlighted the significance of Au(I)/Au(III) redox transitions, unlocking new catalytic pathways. Among the strategies facilitating these oxidative processes, electrochemical anodic oxidation has emerged as a powerful tool. Despite its potential, the electrochemical properties of key gold complexes remain largely underexplored. In this study, we systematically investigate the oxidative behavior of a series of gold complexes using cyclic voltammetry. A comprehensive electrochemical scale is established, revealing that N-heterocyclic carbene (NHC)-based gold complexes are among the least prone to oxidation, whereas phosphorylated ligands significantly enhance oxidizability. Within triphenylphosphine gold complexes, the nature of the X-type anionic ligand plays a crucial role in determining oxidative behavior, a trend rationalized through density functional theory (DFT) calculations of the highest occupied molecular orbital (HOMO). Additionally, hemilabile P^N ligands dramatically facilitate oxidation, correlating with their ability to promote oxidative addition. These findings provide fundamental insights into the redox properties of gold complexes, offering valuable guidelines for the design of new gold-catalyzed transformations. Electrochemistry ; Chemistry ; Combinatorial chemistry ; Catalysis ; Redox ; Oxidative addition ; Ligand (biochemistry) ; Cyclic voltammetry ; Carbene ; Density functional theory ; Triphenylphosphine ; Nanotechnology ; Computational chemistry ; Organic chemistry ; Materials science ; Electrode ; Physical chemistry ; Receptor Catalytic Alkyne Reactions ; Oxidative Organic Chemistry Reactions ; Organometallic Complex Synthesis and Catalysis
Authors: Wai Jue Tan | Arindam Majhi | Wadwan Singhapong | A. C. Walters | M. A. Van Spronsen | Georg Held | Burcu Karagoz | David C. Grinter | Pilar Ferrer | G. Venkat | Qiushi Huang | Zhe Zhang | Zhanshan Wang | Patrick Yuheng Wang | Andréy Sokolov | Hongchang Wang | Kawal Sawhney
Source: Scientific Reports (article, 2025-10-13)
Field: Materials Science — Surfaces, Coatings and Films

High-efficiency multilayer grating for enhanced tender x-ray photoelectron spectroscopy X-ray Photoelectron Spectroscopy (XPS) is a powerful tool for probing the chemical and electronic states of materials with elemental specificity and surface sensitivity. However, its application in the tender X-ray range (1-5 keV) for synchrotron radiation has remained limited due to the limited choice of optics capable of maintaining high reflectivity and efficiency in this energy window. To address this, multilayer (ML) grating structures have become increasingly popular, offering significantly higher efficiency than SL coatings in the tender X-ray region. This paper presents the development of ML laminar gratings optimised for enhancing efficiency in the tender X-ray range, and capable of retaining performance under intense X-ray exposure in the oxygen partial pressure of ∼10[Formula: see text] mbar. The ML coating quality was verified through X-ray reflectivity (XRR), XPS and near-edge X-ray absorption fine structures (NEXAFS) measurements, while the performance of the grating was validated through beamline flux transmission and XPS measurements. The MLLG demonstrated ∼22× higher intensity in flux and XPS, significantly improving the signal-to-noise ratio. Most importantly, the MLLGs outperformed traditional designs by offering improved spectral resolution while maintaining measurement capability at varying [Formula: see text] values without compromising the intensity. Furthermore, we demonstrated that the incorporation of nitrogen during deposition further enhances flux transmission. X-ray photoelectron spectroscopy ; Grating ; Synchrotron radiation ; Absorption (acoustics) ; Synchrotron ; Beamline ; Flux (metallurgy) ; Coating ; Absorption spectroscopy Electron and X-Ray Spectroscopy Techniques ; X-ray Spectroscopy and Fluorescence Analysis ; Electronic and Structural Properties of Oxides
Authors: Elias Dressler | Michelle S. Frei
Source: CHIMIA International Journal for Chemistry (article, 2025-11-26)
Field: Chemistry — Organic Chemistry

Chemigenetic Approaches for the Development of Fluorescent Biosensors for Biological Imaging Fluorescent biosensors are essential for probing analyte dynamics and enzyme activities with high spatial and temporal resolution in living cells by functional microscopy. Recently hybrid, or so called chemigenetic, biosensors have emerged, that integrate the strengths of synthetic fluorophores - such as spectral diversity, high brightness and photostability - with the specificity and sensitivity of genetically encoded sensing units. Beyond enhancing optical performance, synthetic chemistry can also expand the repertoire of sensing units themselves, creating opportunities for novel biosensor designs sensing previously inaccessible analytes. In this review, we summarize the protein-labeling strategies used in chemigenetic biosensor design with particular emphasis on self-labeling protein tags. We further discuss biosensor design principles, representative applications, and emerging advances that highlight the growing impact of chemigenetic biosensors in functional microscopy. Biosensor ; Analyte ; Fluorescent protein ; Fluorescence ; Optical imaging Click Chemistry and Applications ; Biotin and Related Studies ; Luminescence and Fluorescent Materials
Authors: Lütfiye Feray Güleryüz | Rasim İpek
Source: Journal of the Turkish Chemical Society Section A Chemistry (article, 2025-05-17)
Field: Materials Science — Biomaterials

Microstructure-Mechanical Properties of Mg-xCa Alloys Produced by Mechanical Alloying-Hot Pressing Process and Their Optimization Using Central Composite Design Method In the study, Mg-xCa alloys with high mechanical performance were developed using a statistical model central composite design (CCD) method to predict the mechanical properties of Mg and Ca powders produced by powder metallurgy. Powder metallurgy (TM) is a production method that offers great advantages over other production methods. However, there are limited studies in the literature on the production of alloying Ca to eliminate the high degradation rate of pure Mg loss. Mg and Ca powders were subjected to the alloying process for different times as 11.99-14.43-18-21.5-24 h, and after mechanical alloying (MA), grain size measurements of the powders and XRD and SEM-EDS analyses were performed. After MA, the powders were sintered at different temperatures, such as 325-370-437-504-549°C in an argon gas environment under 46 MPa pressure, and samples were obtained. The microstructures, mechanical properties, compressive strength, density values, and XRD-SEM results showed that the secondary phase Mg2Ca increased with increasing Ca content, which indicates the increasing hardness of Mg-xCa alloy. Using the CCD method, the sample's compressive strength, hardness, and density results with optimal values produced from Mg-xCa alloys were determined as 251 MPa, 146 Brinell, and 1.7 g/cm3, respectively. The compatibility of the experimental results with the Regression formula confirms the reliability of the equation. Microstructure ; Composite number ; Chemistry ; Hot pressing ; Process (computing) ; Central composite design ; Pressing ; Metallurgy ; Composite material ; Chromatography ; Response surface methodology ; Materials science ; Crystallography ; Computer science Magnesium Alloys: Properties and Applications ; Aluminum Alloys Composites Properties ; Advanced Welding Techniques Analysis
Authors: Guo-Liang Ma
Source: Biomedical Data Science (article, 2025-01-01)
Field: Chemistry — Organic Chemistry

The Role of Ras Gene in Cancer and Progress in Antibody Research This review seeks to elucidate the significant function of the Ras gene in the pathogenesis of cancer as well as the latest advancements in antibody research aimed at targeting Ras. As a critical oncogene, Ras significantly contributes to the proliferation and metastasis of cancer cells via mutations and the modulation of various signaling pathways. In recent years, a wide array of antibodies has been developed against Ras, offering new strategies and methodologies for cancer treatment. This article will encapsulate the mechanisms underlying Ras gene activation, the associated signaling pathways involved in cancer, and the application of relevant antibodies in both diagnosis and therapy, with the objective of directing future research endeavors within this vital domain of oncology. Antibody ; Cancer ; Gene ; Cancer research ; Political science ; Biology ; Immunology ; Genetics Synthesis and Characterization of Heterocyclic Compounds ; Cancer-related Molecular Pathways ; Protein Kinase Regulation and GTPase Signaling
Authors: Kai Qi | Guoxiang Wang | Xiang Shen | Yixiao Gao
Source: Journal of Optics (article, 2025-12-17)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Switchable high- <i>Q</i> light absorbers based on phase-change resonant metasurfaces Abstract In this paper, we propose a switchable high- Q light absorber based on a reconfigurable metasurface enabled by a lowloss phase-change material (PCM). By leveraging the coupling between guided-mode resonance and Fabry–Perot modes, mediated by the phase-transition dynamics of the embedded PCM, the resonance Q factor can be actively tuned. This allows the system to switch from a perfect dark state, governed by the physics of bound states in the continuum, to a critically coupled resonance with a finite Q factor. Consequently, the metasurface exhibits perfect absorption in the amorphous state and a reflection-dominated response in the crystalline state. The proposed metasurface holds significant potential for diverse nanophotonic applications, including photodetection and thermal emission control. Photodetection ; Resonance (particle physics) ; Nanophotonics ; Absorption (acoustics) ; Coupling (piping) ; Bound state ; Q factor Metamaterials and Metasurfaces Applications ; Acoustic Wave Phenomena Research ; Electromagnetic wave absorption materials
Authors: Nazma Firdosh | Shreyashi Sinha | Indraneel Sinha | Manoj K. Singh | S. Patnaik | Sujit Manna
Source: ArXiv.org (preprint, 2025-06-18)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Intertwined magnetic phase driven exchange bias and its impact on the anomalous Hall effect in MnBi$_4$Te$_7$ We report on the interplay between atomic scale inhomogeneity and competing magnetic phases and its effect on the anomalous Hall effect in the layered antiferromagnet MnBi$_4$Te$_7$, a natural superlattice hosting coexisting ferromagnetic and antiferromagnetic phases. Using a combination of scanning tunneling microscopy (STM), DC and AC magnetization, and magneto-transport measurements, we reveal that intrinsic Mn Bi antisite defects induce strong interlayer exchange coupling, giving rise to a robust exchange bias observed in both magnetic and Hall responses. The exchange bias undergoes a transition from asymmetric to symmetric behavior between 2 K and 6 K, indicating a temperature driven dynamical reconfiguration of interfacial spin structures. The training effect analysis revealed a stronger contribution of frozen spins at 2 K compared to 6 K, with relaxation amplitude shift from -264 Oe to 306 Oe. This sign reversal indicates a field-induced change in interfacial coupling. The temperature dependence of longitudinal resistivity and magnetization reveals complementary behavior, indicating the coexistence of two distinct spin states near the magnetic transition temperature. The phase fraction based resistivity model captures the distinct scattering mechanisms that govern electronic transport across different magnetic regimes. Our findings offer a direct link between microscopic disorder, interfacial magnetism and macroscopic topological phenomena in magnetic topological insulators. Antiferromagnetism ; Ferromagnetism ; Hall effect ; Magnetism ; Superlattice ; Exchange bias ; Magnetization ; Spins ; Spin (aerodynamics) Magnetic and transport properties of perovskites and related materials ; Magnetic Properties of Alloys ; Rare-earth and actinide compounds
Authors: RAGHAVAMMA STV | DIVYA DEVI G
Source: International Journal of Applied Pharmaceutics (article, 2025-12-23)
Field: Chemistry — Analytical Chemistry

AN LC-MS/MS METHOD DEVELOPMENT AND VALIDATION FOR THE QUANTIFICATION OF ANTIVIRAL DRUGS IN PLASMA SAMPLES Objective: A reliable and specific LC-MS/MS method was developed and validated for the simultaneous quantification of cabotegravir (CBTG) and rilpivirine (RLPV) in plasma samples. Methods: Chromatographic separation was achieved on a Hypersil BDS C18 (50 × 4.6 mm, 5 µm) column maintained at 35 °C. The mobile phase consisted of 0.1% HCOOH, acetonitrile, and methanol in the ratio 10:80:10 (v/v/v). The injection volume was 10 µL, and the autosampler temperature was maintained at 10 °C. The retention times for RLPV, internal standard, and CBTG were 2.00, 3.20, and 5.15 min, respectively. Results: Accuracy ranged from 96.32% to 98.19% for CBTG and 95.57% to 97.00% for RLPV. The intra- and inter-day precision values were 0.39%–3.82% RSD for CBTG and 1.56%–4.55% RSD for RLPV. Mean recovery values at three QC levels were 96.14%–97.70% for CBTG and 96.06%–97.75% for RLPV. All stability assessments were within acceptance criteria. Conclusion: The method is robust for the quantitative determination of CBTG and RLPV in biological samples and is suitable for application in forensic, quality-control, bioavailability, and bioequivalence studies. Bioequivalence ; Rilpivirine ; Quantitative analysis (chemistry) ; Accuracy and precision ; Chromatographic separation ; Volume (thermodynamics) Analytical Methods in Pharmaceuticals ; Pharmaceutical Quality and Counterfeiting ; Pesticide Residue Analysis and Safety
Authors: Ching-Hung Shih | Guan-Hao Peng | Ping‐Yuan Lo | Wei-Hua Li | Meiling Xu | Chao-Hsin Chien | Shun‐Jen Cheng
Source: Physical review. B./Physical review. B (preprint, 2025-06-04)
Field: Materials Science — Materials Chemistry

Signatures of valley drift in the diversified band dispersions of bright, gray, and dark excitons in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi mathvariant="normal">MoS</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math> monolayers under uniaxial strains We present a comprehensive theoretical investigation of the strain-modulated excitonic properties of uni-axially strained transition-metal dichalcogenide monolayers (TMD-MLs) by solving the Bethe-Salpeter equation (BSE) established on the basis of first principles. We show that imposing an uni-axial strain onto a MoS_$2$ monolayers leads to the diversified band dispersions of the bright exciton (BX), gray exciton (GX), and dark exciton (DX) states, as a consequence of the competitive interplay between strain-induced valley drift (VD) and momentum-dependent electron-hole exchange interaction (EHEI). While the band dispersions of BX doublet in the light-accessible small reciprocal area remain almost unchanged against strain, the band dispersion of DX is reshaped by an increasing uni-axial strain from a parabola to a Mexican-hat-like profile, featured with unusual sign-reversal of the heavy effective mass and strain-activated brightness. In contrast, the effective mass of GX is drastically lightened by uni-axial strain and remains always positive. We show that the strain-diversified exciton band dispersions leads to the distinct exciton diffusivities and angle-resolved optical patterns of BX, GX, and DX in a strained TMD-ML, suggesting the feasibility of {\it spatially} resolving spinallowed and -forbidden excitons in exciton transport experiments and angle-resolved optical spectroscopies. Exciton ; Monolayer ; Gray (unit) ; Condensed matter physics ; Materials science ; Physics ; Astrophysics ; Nanotechnology ; Medicine 2D Materials and Applications ; Perovskite Materials and Applications ; Ichthyology and Marine Biology
Authors: Batuhan Türközü | Emre Demirci
Source: International Journal of Automotive Science And Technology (article, 2025-09-29)
Field: Materials Science — Polymers and Plastics

Low-Velocity Stone Impact Simulation of Glass Fiber Reinforced Thermoplastics for Diesel Engine Oil Pans under Different Temperature Conditions As environmental regulations continue to evolve, lightweight and high-performance materials have gained increasing attention in the automotive industry. While the shift from metallic to polymer-based engine components contributes to improved fuel efficiency and lower emissions, such transitions also require careful assessment of structural durability under real-world conditions. In this study, a thermoplastic oil pan was developed with design features optimized for impact resistance, including longitudinal and transverse ribs, integrated baffles, and reinforced mounting surfaces. A finite element model of the oil pan was developed in Hypermesh and simulated using Altair Radioss to assess its performance under localized stone impacts, which were modeled using a 17 mm diameter, 6 g rigid sphere. Two impact scenarios—targeting ribbed and non-ribbed regions—were evaluated under three temperature conditions: −40 °C, 23 °C, and 100 °C. Five glass fiber–reinforced thermoplastic composites (PA6-GF30, PA66-GF30, PPA-GF30, PBT-GF30, and PA9T-GF30) were analyzed in terms of energy absorption, maximum local displacement, and damage behavior. The results showed that rib structures effectively reduced crack formation and localized stress, especially at lower temperatures. Performance depends on impact location, so no single material ranks best in all cases; ribbed regions tend to favor PA6/PA66, whereas non-ribbed regions can favor PPA/PBT. Although no physical tests were conducted, the material modeling was supported by experimental data in the literature. This study contributes to the growing body of knowledge on lightweight thermoplastic oil pans and offers a practical methodology for evaluating their impact performance under service-like conditions. Thermoplastic ; Glass fiber ; Finite element method ; Automotive industry ; Thermoplastic composites ; Impact energy ; Diesel engine Natural Fiber Reinforced Composites ; Mechanical Behavior of Composites ; Cellular and Composite Structures
Authors: A. V. Rozhkov
Source: Physical review. B./Physical review. B (preprint, 2025-05-27)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Umklapp-driven first-order transition into a charge density wave phase Using phenomenological Landau free energy, we systematically analyze the influence of so-called umklapp contributions on the phase diagram of a solid hosting a commensurate charge density wave phase. The umklapp terms may change the transition into the ordered state from continuous (second order) to discontinuous (first order). Additional elements, such as critical and tricritical points, emerge on the phase diagram under suitable conditions. The proposed mechanism is generalized for the case of a nearly commensurate charge density wave, as well as spin-density wave orders. Several charge-density-wave-hosting alloys are used as experimentally available examples illustrating the formalism. Charge density wave ; Order (exchange) ; Phase transition ; Condensed matter physics ; Charge (physics) ; Transition (genetics) ; Phase (matter) ; Charge density ; Physics ; Quantum electrodynamics ; Chemistry ; Quantum mechanics ; Business Organic and Molecular Conductors Research ; Molecular Junctions and Nanostructures ; Force Microscopy Techniques and Applications
Authors: J. Hodgkinson | Nicholas M. Davis | Cormac Browne | Kamal Nesnas | Stuart McRobbie | A Wright | Ralph P. Tatam
Source: Scientific Reports (article, 2025-07-11)
Field: Chemistry — Analytical Chemistry

Mid-IR standoff measurement of ageing-related spectroscopic changes in bitumen in the 6 µm (1700 cm−1) region. Part 1: Measurement strategy and instrument design principles A strategy is described to make in-situ measurements of a spectroscopic marker of ageing in bitumen binders used on asphalt-paved roads. Oxidation of bitumen at the surface increases the number of carbonyl (C=O) bonds, and this can be measured in the 6 μm region (1700 cm<sup>-1</sup>) of the mid-infrared. A measurement strategy is proposed to make standoff measurements of surface reflectivity in this region, despite the challenge presented by numerous strong absorption lines from atmospheric water vapour within the optical path. An instrument design is described to make measurements at 4 discrete laser wavelengths, namely 1593.0, 1641.4 and 1731.3 cm<sup>-1</sup> (around 6 µm) and at 2633.6 cm<sup>-1</sup> (3.8 µm), the first 3 responding to carbonyl absorption and the fourth acting as a spectral reference that is substantially unaffected by ageing. Part 2 of this paper describes the implementation of such an instrument and its experimental performance. Asphalt ; Absorption (acoustics) ; Laser ; Wavelength ; Materials science ; Ageing ; Water vapor ; Environmental science ; Optics ; Analytical Chemistry (journal) ; Remote sensing ; Optoelectronics ; Geology ; Chemistry ; Composite material ; Meteorology ; Environmental chemistry ; Physics Spectroscopy and Chemometric Analyses ; Water Quality Monitoring and Analysis ; Spectroscopy and Laser Applications
Authors: Khawla Qamhieh
Source: Colloids and Interfaces (article, 2025-07-01)
Field: Chemistry — Physical and Theoretical Chemistry

Effect of Dielectric Constant on Interaction Between Charged Macroions in Asymmetric Electrolyte The mean force between two highly like-charged macroions in the presence of monovalent counterions and added multivalent salt within solvents of varying dielectric constants was studied using Monte Carlo simulations. Without additional salt, the mean force is strongly repulsive at all macroion separations in solvents with a dielectric constant ϵr ≥ 30. However, in solvents with ϵr ≤ 30, macroions experience effective attraction, indicating that attractive interactions between highly charged macroions can occur even without multivalent salt in nonpolar solvents with low dielectric constants. The total multivalent counterion charge-to-total macroion charge ratio is defined as β which determines the amount of salt that is added to the system. At β = 0.075, the mean force becomes attractive at short separations in solvents with ϵr = 54 containing 1:3 salt, as well as in all solvents with 1:5 salt, while still exhibiting significant repulsion at longer separations. In contrast, for solvents with 1:3 salt and dielectric constants ϵr = 68 and ϵr = 78.4, the mean force turns attractive at a higher salt concentration, around β = 0.225. The shift in the mean force to an attractive state at short separations signifies charge inversion on the macroion surface when a sufficient amount of salt is present. At a stoichiometric ratio of multivalent counterions, long-range repulsion vanishes, and attraction becomes significant. However, with excess salt, the strength of the attractive mean force diminishes. Additionally, the attractive force at a given salt concentration increases as the dielectric constant decreases and is stronger in systems with 1:5 salt than in those with 1:3 salt. Chemistry ; Dielectric ; Counterion ; Electrolyte ; Salt (chemistry) ; Chemical physics ; Potential of mean force ; Solvent ; Ion ; Computational chemistry ; Physical chemistry ; Molecular dynamics ; Materials science ; Organic chemistry Electrostatics and Colloid Interactions ; Material Dynamics and Properties ; Geophysical and Geoelectrical Methods