jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Marco F. Valtierra-Galvan | Alfredo Rodríguez‐Hernández | Israel Bonilla‐Landa | Felipe Barrera‐Méndez | Francisco Javier Enríquez‐Medrano | Ramón Díaz de León | José Luís Olivares-Romero
Source: Molecules (article, 2025-11-06)
Field: Chemistry — Inorganic Chemistry

A Comparative Study of C2-Symmetric and C1-Symmetric Hydroxamic Acids in Vanadium-Catalyzed Asymmetric Epoxidation of Allylic Alcohols Hydroxamic acids are emerging as versatile chiral ligands for metal-catalyzed asymmetric oxidations due to their tunable electronic and steric environments. In this study, we systematically compared the catalytic behavior of <i>C</i><sub>2</sub>- and <i>C</i><sub>1</sub>-symmetric hydroxamic acid ligands in the vanadium-catalyzed asymmetric epoxidation of allylic alcohols. A series of chiral hydroxamic acids (HA1-HA7) was synthesized and evaluated under varied conditions to elucidate the influence of ligand symmetry on enantioinduction and reactivity. The results demonstrate that <i>C</i><sub>2</sub>-symmetric bishydroxamic acids generate a highly organized chiral environment, leading to high enantioselectivity but often limited conversion, consistent with the Sabatier principle. Conversely, certain <i>C</i><sub>1</sub>-symmetric ligands-particularly HA3-produced notable enantioselectivity (up to 71% <i>e.e.</i>) and full conversion under optimized conditions with VO(O<i>i</i>Pr)<sub>3</sub> in CH<sub>2</sub>Cl<sub>2</sub>. A quadrant-based stereochemical model is proposed to rationalize the differential performance of these ligands. These findings highlight the critical role of ligand desymmetrization in modulating the chiral environment around vanadium centers, providing valuable design principles for next-generation hydroxamic acid-based catalysts in asymmetric synthesis. The optimized system (VO(O<i>i</i>Pr)<sub>3</sub>/HA3 in CH<sub>2</sub>Cl<sub>2</sub>) afforded >99% conversion and 71% <i>e.e.</i>, providing a basis for extending hydroxamic acid scaffolds to diverse allylic alcohols. Allylic rearrangement ; Hydroxamic acid ; Desymmetrization ; Steric effects ; Catalysis ; Ligand (biochemistry) ; Enantioselective synthesis ; Vanadium Metal-Catalyzed Oxygenation Mechanisms ; Polyoxometalates: Synthesis and Applications ; Vanadium and Halogenation Chemistry
Authors: L. Wei | Yushuang Li | Ke Cong | Junde Chen | Jing Zhang
Source: Foods (article, 2025-09-28)
Field: Materials Science — Biomaterials

Thermally Stable Collagen from Black Carp (Mylopharyngodon piceus) Swim Bladder: Preparation, Structure, Rheological, and Functional Properties Fish-derived collagen can reduce the risk of disease transmission and has no religious or cultural restrictions. However, it has limited applications due to its poor thermal stability. In this study, black carp swim bladder collagen (BBC), classified as a type I collagen, was extracted. Amino acid composition analysis revealed that BBC had a higher proline hydroxylation rate of 39.57%. Fourier transform infrared spectroscopy revealed that BBC exhibited a complete triple-helix structure. The fractional viscosity curve and differential scanning calorimetry curves revealed that the thermal denaturation temperature (Td) and the melting temperature (Tm) were 30.85 °C and 107.19 °C, respectively. The dynamic rheological analysis showed that as the concentration increased from 5 mg/mL to 20 mg/mL at 0.01 Hz, the storage modulus increased from 0.979 Pa to 84.2 Pa. When the temperature exceeded the Td, the BBC solution exhibited viscous behaviour as the frequency increased. The steady-shear analysis showed that the BBC was a shear-thinning fluid. Functional properties analysis revealed that BBC exhibited better emulsification properties, foaming properties, water absorption capacity and oil absorption capacity than land-derived collagen, making it suitable for emulsifiers, bubbling beverages, and frozen meat preservation. Additionally, BBC promoted the growth of MT3C3-E1 cells and maintained the normal morphology of the cells. These results showed that BBC is a promising substitute for terrestrial collagen in functional foods, cosmetics, and biofunctional materials. Differential scanning calorimetry ; Rheology ; Dynamic mechanical analysis ; Absorption of water ; Fourier transform infrared spectroscopy ; Thermal analysis ; Absorption (acoustics) ; Proline ; Viscosity Collagen: Extraction and Characterization ; Meat and Animal Product Quality ; Proteins in Food Systems
Authors: Helena Cristina Vasconcelos | Maria Meirelles | Reşit Özmenteş | Luís F. Santos
Source: Foundations (article, 2025-02-12)
Field: Materials Science — Ceramics and Composites

Structural Analysis of Erbium-Doped Silica-Based Glass-Ceramics Using Anomalous and Small-Angle X-Ray Scattering This study employs advanced structural characterization techniques, including anomalous small-angle X-ray scattering (ASAXS), small-angle X-ray scattering (SAXS), and X-ray photoelectron spectroscopy (XPS), to investigate erbium (Er3+)-doped silica-based glass-ceramic thin films synthesized via the sol–gel method. This research examines the SiO2-TiO2 and SiO2-TiO2-PO2.5 systems, focusing on the formation, dispersion, and structural integration of Er3+-containing nanocrystals within the amorphous matrix under different thermal treatments. Synchrotron radiation tuned to the LIII absorption edge of erbium enabled ASAXS measurements, providing element-specific details about the localization of Er3+ ions. The findings confirm their migration into crystalline phases, such as erbium phosphate (EPO) and erbium titanate (ETO). SAXS and Guinier analysis quantified nanocrystal sizes, revealing trends influenced by their composition and heat treatment. Complementary XPS analysis of the Er 5p core-level states provided detailed information on the chemical and electronic environment of the Er3+ ions, confirming their stabilization within the crystalline structure. Transmission electron microscopy (TEM) highlighted the nanoscale morphology, verifying the aggregation of Er3+ ions into well-defined nanocrystals. The results offer a deeper understanding of their size, distribution, and interaction with the surrounding matrix. Erbium ; Doping ; Materials science ; Ceramic ; Silica glass ; Scattering ; Small-angle X-ray scattering ; Sol-gel ; X-ray ; Optics ; Mineralogy ; Optoelectronics ; Composite material ; Nanotechnology ; Chemistry ; Physics Glass properties and applications ; Recycling and utilization of industrial and municipal waste in materials production ; Material Science and Thermodynamics
Authors: Jae Seo Park | Seo Mi Yang | Young Joo Park | Young Joon Park | Y. J. Sim | Hee Rim Nam | So Eun Kim | Jae Ho Kim | Seung Jae Yang
Source: Small (article, 2025-06-26)
Field: Chemistry — Inorganic Chemistry

Microstructural Engineering of Conductive MOF Nanocrystals for Multifunctional Heterostructures Conductive metal-organic frameworks (cMOFs) have emerged as transformative materials, significantly expanding the functional landscape of conventional MOFs by integrating electrical conductivity. Despite this, harnessing their full potential in heterostructured architectures is constrained by challenges in finely tuning the critical structural parameters, notably the packing density and crystallographic orientation. This paper introduces an innovative approach to engineering the microstructure of cMOFs as conformal shell-enveloping spherical nanoparticles. The compactness of the cMOF layer is modulated by the crystallization kinetics, while a deliberate seeding process directed the alignment of cMOF nanocrystallites. These methodologies collectively facilitated the formation of densely packed, highly ordered nanocrystallite assemblies in a core-shell configuration, enhancing mechanical robustness, selective permeability, and electron transport. The resulting cMOF assembly markedly augmented the stability and electrochemical performance of the sulfur core, showing significant promise as a next-generation cathode material for lithium-sulfur batteries. Materials science ; Nanotechnology ; Metal-organic framework ; Nanocrystal ; Heterojunction ; Microstructure ; Electrical conductor ; Cathode ; Anode ; Nanoparticle ; Nanocomposite ; Crystallization ; Microscale chemistry ; Chemical engineering ; Electrode ; Composite material ; Optoelectronics ; Adsorption ; Chemistry Metal-Organic Frameworks: Synthesis and Applications ; MXene and MAX Phase Materials ; Advanced Battery Materials and Technologies
Authors: Adam Svítok | Carlos Platas‐Iglesias | Jan Kotek | Petr Hermann
Source: Inorganic Chemistry Frontiers (article, 2025-11-06)
Field: Materials Science — Materials Chemistry

Phosphorus chirality assignment and solution dynamics of lanthanide( <scp>iii</scp> ) complexes of a monomethylphosphinate analogue of H <sub>4</sub> dota: a multinuclear NMR and DFT study Orientation of the substituents of the coordinated phosphinate group was experimentally determined for the first time and exchange between its coordinated/non-coordinated oxygen atoms (“phosphinate rotation”) was experimentally/computationally confirmed. Phosphinate ; Chirality (physics) ; Dynamics (music) ; Phosphorus ; Oxygen atom ; Oxygen ; Phosphorus-31 NMR spectroscopy Lanthanide and Transition Metal Complexes ; Organophosphorus compounds synthesis ; Synthesis and characterization of novel inorganic/organometallic compounds
Authors: S. W. Jessen | Alessio Di Giacomo | Iwan Moreels | Brian Julsgaard | Rosana M. Turtos
Source: Scientific Reports (article, 2025-07-02)
Field: Materials Science — Materials Chemistry

Nonlinear quenching of excitonic emission from nanoplatelet films at high excitation densities The conversion of gamma particles into optical photons in state-of-the-art scintillator materials is limited to maximum 10 emitted photons per MeV of energy deposited per picosecond, when the material is excited at room-temperature. Breaking this limit has both fundamental and applied importance, and motivates the search for fast and efficient optical emitters at excitation densities relevant for particle detection, up to 10<sup>20</sup> electron-hole pairs (eh) per cm<sup>3</sup>. In this work, we address this challenge by probing the optical response of a promising nanomaterial, CdSe/CdS core/crown nanoplatelets (NPLs), in the shape of drop cast films using intense femtosecond laser pulses. The study finds that the NPL films exhibit a bright optical response at low to medium excitation densities but suffer from high levels of nonlinear quenching, dominated by exciton-exciton annihilation (EEA), at densities exceeding 10<sup>17</sup> eh/cm<sup>3</sup>. The experimental data and theoretical calculations suggest that EEA is enhanced in the drop cast film by the close packing of NPLs which allows excitons to migrate between NPLs in the film. Despite this, light yield estimations based on a simulated distribution of excitation densities predict values upwards of 2000 ph/MeV, while showing ample room for improvement and the future potential of surpassing the 10 ph/MeV/ps benchmark. Quenching (fluorescence) ; Excitation ; Materials science ; Nonlinear system ; Optoelectronics ; Molecular physics ; Atomic physics ; Chemistry ; Fluorescence ; Physics ; Optics ; Quantum mechanics Quantum Dots Synthesis And Properties ; Perovskite Materials and Applications ; Luminescence and Fluorescent Materials
Authors: Adrien Denizet | Rajesh Nomula | Richard J. Edwards | Patrick Y. Toullec | Philippe A. Peixoto
Source: Chemistry - A European Journal (article, 2025-03-07)
Field: Chemistry — Organic Chemistry

Asymmetric Total Synthesis of (+)‐ and (−)‐Myrioneurinol Employing a “Resolutive” Late‐Stage Barton‐McCombie Deoxygenation The so-called Barton-McCombie reaction is a transformation commonly used in organic synthesis for promoting deoxygenation of alcohols. Almost 50 years after its discovery, this reaction has become a powerful tool for organic chemists due to its wide range of applicability and functional group tolerance, which allows, with high level of anticipation, its incorporation into complex synthetic routes such as the ones aiming at the total synthesis of natural products. In this article, we describe the first example of a resolutive version of this reaction by using a chiral chlorothionoformate as the activating reagent, and its related strategic potential through a late-stage application to the total synthesis of both enantiomers of myrioneurinol, a complex tetracyclic alkaloid featuring 5 contiguous stereogenic centers. Deoxygenation ; Total synthesis ; Stereocenter ; Anticipation (artificial intelligence) ; Enantiomer ; Reagent ; Chemistry ; Transformation (genetics) ; Combinatorial chemistry ; Computer science ; Organic chemistry ; Enantioselective synthesis ; Artificial intelligence ; Catalysis Advanced Synthetic Organic Chemistry ; Chemical synthesis and alkaloids ; Alkaloids: synthesis and pharmacology
Authors: Hélène Pung | Celso Y. Okada | Mirella Simões Santos | Marta Mirolo | Isabelle Morfin | Gilbert Chahine | Jannick Duchet‐Rumeau | Johan Jacquemin | Agı́lio A. H. Pádua | Sébastien Livi | Patrice Rannou | Manuel Maréchal
Source: Advanced Science (article, 2025-08-11)
Field: Materials Science — Biomaterials

Dynamic Mosaicity Modulates Ion Transport in Stimuli‐Responsive Liquid Crystal Electrolytes Structural mosaicity and defects are ubiquitous across materials and critically influence functional properties, from semiconductors to biological membranes. In soft matter electrolytes, these features remain difficult to probe and exploit due to complex synthesis and limited long-range structural order. A dimensionally tunable model system based on thermotropic ionic liquid crystals (TILCs) is introduced to investigate the interplay between structural mosaicity and ion transport. In two-dimensional (2D) anion-conducting smectic TILCs, ion transport exhibits a pronounced anisotropy-up to four orders of magnitude at 70 °C-attributed to ion confinement within 0.7-1.2 nm-thick lamellar sublayers. In situ and operando synchrotron X-ray scattering combined with electrochemical analyses reveal direct experimental evidence of a strong correlation between long-range supramolecular organization, quantified via dynamic mosaicity, and mesoscopic ion transport. Application of a 1 Tesla magnetic field enhances domain size by 1.5× and boosts conductivity threefold, demonstrating stimuli-responsive, mosaicity-controlled ionic transport. These findings establish a generalizable structure-function framework for confined ion conduction in soft materials and bridge concepts from thermotropic liquid crystals to lyotropic phases, biological assemblies, and organic semiconductors. Positioning dynamic mosaicity as a key design parameter, this work lays the foundation for rational development of adaptive, self-organized electrolyte systems for energy storage and conversion, ionotronics, and bioinspired ionic devices. Materials science ; Mosaicity ; Chemical physics ; Ionic liquid ; Ion transporter ; Electrolyte ; Ion ; Nanotechnology ; Chemistry ; Electrode ; Physical chemistry ; Organic chemistry Supramolecular Self-Assembly in Materials ; Conducting polymers and applications ; Liquid Crystal Research Advancements
Authors: S. H. Huo | Shudong Luo | Ruishen Wang | Jingnan Zhao | Wenfeng Miao | Zhiquan Guo | Yuanchen Cui
Source: Coatings (article, 2025-10-10)
Field: Materials Science — Materials Chemistry

Controlled Nanopore Fabrication on Silicon via Surface Plasmon Polariton-Induced Laser Irradiation of Metal–Insulator–Metal Structured Films In this study, we present a cost-effective approach for fabricating nanopores on single-crystal silicon using a silver–alumina–silver (Ag/AAO/Ag) metal–insulator–metal (MIM) structured mask. Self-ordered porous anodic aluminum oxide (AAO) films were prepared via two-step anodization and coated with silver layers on both sides to form the MIM structure. When irradiated with a 532 nm nanosecond laser, the MIM mask excites surface plasmon polaritons (SPPs), resulting in a localized field enhancement that enables the etching of nanopores into the silicon substrate. This method successfully produced nanopores with diameters as small as 50 nm and depths up to 28 nm. The laser-induced SPP-assisted machining significantly enhances the specific surface area of the processed surface, making it promising for applications in catalysis, biosensing, and microcantilever-based devices. For instance, an increased surface area can improve catalytic efficiency by providing more active sites, and enhance sensor sensitivity by amplifying response signals. Compared to conventional lithographic or focused ion beam techniques, this method offers simplicity, low cost, and scalability. The proposed technique demonstrates a practical and efficient route for the large-area subwavelength nanostructuring of silicon surfaces. Nanopore ; Silicon ; Anodizing ; Etching (microfabrication) ; Porous silicon ; Fabrication ; Surface plasmon ; Plasmon ; Lithography ; Electron-beam lithography Anodic Oxide Films and Nanostructures ; Nanowire Synthesis and Applications ; Nanopore and Nanochannel Transport Studies
Authors: Hayriye Aral | Yekun Altun
Source: Open Chemistry (article, 2025-01-01)
Field: Chemistry — Spectroscopy

Separation of sulphonamides on a C12-diol mixed-mode HPLC column and investigation of their retention mechanism Abstract Sulphonamides exhibit broad-spectrum antibacterial effects. However, their extensive use poses health risks, such as antimicrobial resistance. Therefore, advanced and accurate analytical techniques are needed to monitor the presence of sulphonamide residues. In this study, a mixture of eight sulphonamides was separated on a C12-diol mixed-mode column containing both a hydrophobic C12 chain and a hydrophilic diol group. The influence of various experimental parameters, including pH, buffer concentration, mobile phase composition, temperature, and flow rate, on the separation efficiency of the column was investigated. All eight sulphonamides were separated within 20 min via gradient elution with an acetonitrile/phosphate buffer (pH 6.5, 40 mM KH 2 PO 4 /K 2 HPO 4 ) solution at 15°C and a detection wavelength of 250 nm. Examination of the retention times of the analytes at different pH values ranging from 3 to 7 revealed that the sulphonamides were significantly affected by the acidity of the medium, thus enabling a detailed discussion of the mixed-mode separation mechanism. The interaction mechanism between the eight sulphonamides and the C12-diol mixed-mode column was explored using quantitative structure–retention relationship parameters such as log D , log S , and p K a . Although the interaction of the sulphonamides with the C12-diol mixed-mode column partly showed the classic reverse-phase feature, polar interactions played a major role, and the mixed-mode interaction mechanism was dominated by polar and apolar interactions. The results obtained were compared with a commercial ODS-C18 column in terms of both separation performance and retention behaviour. Chromatography ; High-performance liquid chromatography ; Column (typography) ; Diol ; Retention time ; Chemistry ; Separation (statistics) ; Computer science ; Mathematics ; Organic chemistry ; Statistics ; Telecommunications Analytical Chemistry and Chromatography ; Analytical chemistry methods development ; Analytical Methods in Pharmaceuticals
Authors: Maoz Maoz | Syed Abdul Basit Shah | Vanni Lughi
Source: ACS Omega (article, 2025-09-08)
Field: Materials Science — Materials Chemistry

Photoluminescence Enhancement in CdSe/CdS Quantum Dot Colloidal Films Induced by Gold Nanoparticles (AuNPs) The optical properties of quantum dots (QDs) can be altered by employing surface plasmon metallic nanoparticles close to the QDs. In this study, we investigate the photoluminescence (PL) enhancement of CdSe/CdS core-shell QDs coupled with gold nanoparticles (AuNPs) due to the plasmonic effect. The effect of the morphology of AuNPs and the importance of the spacer layer were also analyzed. The AuNPs are deposited on a glass substrate by magnetron sputtering to achieve precise morphological control. The deposited nanoparticles have a uniform distribution and optimal particle size ranging between 10 and 12 nm. A poly-(methyl methacrylate) (PMMA) spacer layer was employed between QDs and AuNPs to control the separation and avoid quenching effects due to Förster resonance energy transfer (FRET). Maximum PL enhancement was observed for a spacer layer of 25 nm thickness due to the plasmonic effect. This coupled structure can potentially be used to enhance the PL of QDs acting as a downshifting layer, which can be used to improve the power conversion efficiency (PCE) and improve light trapping in solar cells. Photoluminescence ; Quantum dot ; Surface plasmon resonance ; Plasmon ; Colloidal gold ; Nanoparticle ; Layer (electronics) ; Substrate (aquarium) Quantum Dots Synthesis And Properties ; Chalcogenide Semiconductor Thin Films ; Gold and Silver Nanoparticles Synthesis and Applications
Authors: F. Schumann | Joachim Podlech
Source: European Journal of Organic Chemistry (article, 2025-02-14)
Field: Chemistry — Organic Chemistry

Synthesis of Quinolino[4,3‐<i>j</i>]phenanthridines and their Photophysical Characterization Abstract Quinolino[4,3‐ j ]phenanthridines were synthesized from para ‐terphenyl‐2,2′′‐diamines, which were obtained by cross‐coupling reactions. The diamines were converted into amides and ortho ‐cyclized to quinolino[4,3‐ j ]phenanthridines using Morgan‐Walls reactions. Prolonged reaction times were required in these electrophilic substitution reactions to overcome the respective deactivated intermediates formed after the first ortho fusion. Optophysical properties were determined by UV/Vis and fluorescence spectroscopy and calculated by quantum chemical calculations. The compounds exhibit rather small HOMO/LUMO gaps and a remarkable bathochromic shift of luminescence upon protonation, what makes these compounds promising candidates for optoelectronic applications. Chemistry ; Characterization (materials science) ; Stereochemistry ; Combinatorial chemistry ; Nanotechnology Catalytic C–H Functionalization Methods ; Axial and Atropisomeric Chirality Synthesis ; Chemical synthesis and alkaloids