jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Erin Van Rooyen | Eric C. Hosten | Richard Betz
Source: IUCrData (article, 2025-11-25)
Field: Chemistry — Inorganic Chemistry

<scp>L</scp> -Valine ethyl ester hydrochloride The title compound [systematic name: (2<i>S</i>)-1-ethoxy-3-methyl-1-oxobutan-2-aminium chloride], C<sub>7</sub>H<sub>16</sub>NO<sub>2</sub> <sup>+</sup>·Cl<sup>-</sup>, is the hydro-chloride salt of the ethyl ester of l-valine. In the crystal, classical hydrogen bonds of the N-H⋯Cl type are observed alongside C-H⋯O and C-H⋯Cl contacts, connecting the entities of the asymmetric unit into sheets lying perpendicular to the crystallographic <i>a</i> axis. Ethyl ester ; Hydrogen bond ; Hydrochloride ; Crystal structure ; Salt (chemistry) ; Ethyl acetate Crystal structures of chemical compounds ; Crystallography and molecular interactions ; Chemical Synthesis and Analysis
Authors: Wa Gao | Lei Xu
Source: GBP Proceedings Series (article, 2025-10-08)
Field: Materials Science — Materials Chemistry

Preparation and Photoluminescence Properties of Eu&lt;sup&gt;3+&lt;/sup&gt;-Doped Na&lt;sub&gt;2.4&lt;/sub&gt;Mg&lt;sub&gt;0.8&lt;/sub&gt;(MoO&lt;sub&gt;4&lt;/sub&gt;)&lt;sub&gt;2&lt;/sub&gt; Red-Emitting Phosphors Eu³⁺-doped Na₂.₄Mg₀.₈(MoO₄)₂ red phosphors were successfully synthesized using a facile sol-gel method, achieving uniform morphology and high crystallinity. The structural and optical properties of the resulting phosphors were systematically characterized, revealing insights into their photoluminescence behavior. Photoluminescence excitation (PLE) spectra demonstrated a broad excitation range spanning the near-ultraviolet (UV) to blue regions, accompanied by sharp and well-defined peaks, indicating effective energy absorption by Eu³⁺ ions. Specifically, the strongest excitation peak at 465 nm corresponding to the ⁷F₀ → ⁵D₂ transition, and a relatively weaker peak at 395 nm corresponding to the ⁷F₀ → ⁵L₆ transition, suggest that these phosphors can be efficiently excited under both blue and near-UV light sources. Upon 465 nm excitation, the emission spectra exhibited characteristic Eu³⁺ transitions, including the magnetic dipole ⁵D₀ → ⁷F₁ transition at 591 nm and the hypersensitive electric dipole ⁵D₀ → ⁷F₂ transition at 614 nm, with the red emission at 614 nm dominating and exhibiting an intensity nearly ten times higher than that at 591 nm. This pronounced red emission highlights the strong asymmetry of the local environment around Eu³⁺ ions, which is beneficial for enhancing the color purity of the emitted light. Furthermore, the Na₂.₄₋ₓMg₀.₈(MoO₄)₂:Euₓ³⁺ phosphors demonstrated excellent thermal stability and potential for integration into solid-state lighting devices. The tunable Eu³⁺ doping concentrations enabled modulation of the emission intensity and color, providing flexibility for device design and optimization. These characteristics, combined with efficient energy transfer from the host lattice to Eu³⁺ ions, suggest that these phosphors are promising candidates for red-emitting components in white light-emitting diodes (LEDs), especially when combined with commercial blue LED chips. The findings offer a comprehensive understanding of the relationship between host lattice composition, Eu³⁺ doping, and photoluminescence performance, providing valuable guidance for the development of high-performance, rare-earth-based phosphors in next-generation lighting technologies. Phosphor ; Photoluminescence ; Excited state ; Doping ; Excitation ; Luminescence ; Emission spectrum ; Magnetic dipole transition ; Diode Luminescence Properties of Advanced Materials ; Transition Metal Oxide Nanomaterials ; Lanthanide and Transition Metal Complexes
Authors: Minh Hoa Nguyễn
Source: ChemistrySelect (article, 2025-04-01)
Field: Materials Science — Materials Chemistry

Influence of Sulfur Precursor Reactivity on Size‐Controlled and Optical Properties of CdS Nanocrystals Abstract This study investigates the synthesis of cadmium sulfide (CdS) nanocrystals (NCs) using a hot‐injection method, focusing on how sulfur precursor reactivity, controlled by its preparation temperature, influences the final nanomaterial properties. The sulfur precursor was prepared at three temperatures (120, 140, and 180 °C) to modulate its reactivity. Transmission electron microscopy, UV–vis spectroscopy, and photoluminescence spectroscopy were employed to characterize the size, morphology, and optical properties of the resulting CdS NCs. We found a clear correlation between the sulfur precursor preparation temperature and the CdS nanocrystal properties. The precursor prepared at 140 °C resulted in the most homogeneous growth, leading to the smallest size distribution and highest quality NCs, as evidenced by the higher PL intensity. The precursor prepared at 180 °C resulted in a faster growth rate, ultimately leading to larger NCs with inhomogeneous morphologies, while the 120 °C precursor exhibited the slowest growth rate, producing larger particles with a wider size distribution. These findings underscore the significant role of sulfur precursor preparation temperature in controlling the final CdS nanocrystal material properties, offering valuable insights for the tailored synthesis of high‐quality CdS nanomaterials for diverse applications. Nanocrystal ; Reactivity (psychology) ; Materials science ; Sulfur ; Particle size ; Chemical engineering ; Nanotechnology ; Metallurgy ; Medicine Quantum Dots Synthesis And Properties ; Chalcogenide Semiconductor Thin Films ; Advanced Thermoelectric Materials and Devices
Authors: Chen Dong | Koen Robeyns | Tom Leyssens | Basanta Saikia | Stijn Van Cleuvenbergen
Source: Gels (article, 2025-07-01)
Field: Materials Science — Materials Chemistry

Polymorphic Control in Pharmaceutical Gel-Mediated Crystallization: Exploiting Solvent–Gelator Synergy in FmocFF Organogels FmocFF is a highly versatile gelator whose π-π-stacking fluorenyl group and hydrogen-bonded peptide backbone permit gelation in a wide spectrum of solvents, providing a rich scaffold for crystal engineering. This study explores the synergistic effects of FmocFF organogels and solvent selection on controlling the polymorphic outcomes of nilutamide, a nonsteroidal antiandrogen drug with complex polymorphism. By systematically varying process parameters such as solvent type and concentration, we demonstrate remarkable control over crystal nucleation and growth pathways. Most significantly, we report the first ambient-temperature isolation of pure nilutamide Form II through acetonitrile-based FmocFF organogel, highlighting the unique interplay between solvent properties and gel fiber networks. Thermal analysis reveals that the organogel not only selectively templates Form II but also affects its thermal pathway. We also present compelling evidence for a new polymorph exhibiting second-harmonic generation (SHG) activity. This would represent the first non-centrosymmetric nilutamide form discovered, suggesting the gel matrix induces symmetry breaking during crystallization. We also characterize a previously unreported nilutamide-chloroform solvate through multiple analytical techniques including PXRD, DSC, FTIR, SXRD, and SHG microscopy. Our findings demonstrate that solvent-specific molecular recognition within gel matrices enables access to entirely new regions of polymorphic space, establishing gel-mediated crystallization as a broadly applicable platform technology for pharmaceutical solid form discovery under mild conditions. Crystallization ; Solvent ; Chemical engineering ; Materials science ; Nanotechnology ; Chemistry ; Organic chemistry Crystallization and Solubility Studies ; Enzyme Structure and Function ; Crystallography and molecular interactions
Authors: Amaury Baret | Jürgen Baumgarten | François Balty | Frédéric Rabecki | Jérémy Brisbois | Buyun Zheng | Daniel Bellet | Ngoc Duy Nguyen
Source: Discover Nano (article, 2025-08-08)
Field: Materials Science — Materials Chemistry

The refractive index of silver nanowire networks: a heuristic approach to the foundations of the optical constants, from experiment to theory This study employs Mie's scattering theory and van de Hulst's mixing model to predict the refractive indices (n, k) of silver nanowire (AgNW) networks in the visible and near-infrared wavelengths, allowing the comparison to the experimentally determined k spectra. Transmittance spectra calculated via the numerical resolution of Fresnel's equations are compared to experimental data, showing excellent agreement, particularly for nanowires with larger diameters and at shorter wavelengths. These findings, both theoretical and empirical, pave the way for accurate optical simulations of metallic nanowire networks, supporting their integration into complex multilayer systems and devices such as displays or smart windows. Notably, our work proposes the first demonstration of the dominance of the metallic character of AgNW networks over their dielectric behavior in terms of optical response. Nanowire ; Refractive index ; Mie scattering ; Wavelength ; Materials science ; Dielectric ; Transmittance ; Optics ; Fresnel equations ; Scattering ; Spectral line ; Optoelectronics ; Light scattering ; Physics ; Quantum mechanics ZnO doping and properties ; Nanomaterials and Printing Technologies ; Gold and Silver Nanoparticles Synthesis and Applications
Authors: Eryn Lundrigan | Parrish Evers | E.M. Scott | John Paul Pezacki
Source: Angewandte Chemie International Edition (review, 2025-12-13)
Field: Chemistry — Organic Chemistry

Unnatural Amino Acid and Emerging Chemistry Approaches to Map RNA–Protein Interactions RNA serves as both a genetic messenger and a functional non-coding molecule, with its activity relying on interactions with diverse proteins. Characterizing RNA-protein interactions remains challenging, particularly for dynamic or low-abundance complexes. Traditional crosslinking methods, such as UV-254 nm irradiation and formaldehyde fixation, suffer from low efficiency, poor specificity, and broad reactivity, limiting their utility for high-resolution interactome mapping. Recent advances in genetic code expansion (GCE) and unnatural amino acid (UAA) incorporation now enable chemoselective, site-specific crosslinking chemistries that circumvent these limitations. This review highlights classes of crosslinkable UAAs, including benzophenone-, diazirine-, and aryl azide-based moieties, which have been used for photo-induced covalent capture of RNA-protein interactions. Next-generation modalities, such as acetophenone derivatives, halogenated UAAs, bifunctional UAAs, acyl silanes, diaryl nitrones, and photoactivatable systems further expand the toolkit for photocrosslinking and bioorthogonal labelling. Beyond UV-based approaches, latent bioreactive UAAs and proximity-induced chemistries exploit electrophile-nucleophile substitution and masked acylating agents to enable covalent capture under physiological conditions. Together, these strategies provide unprecedented control over reactivity, temporal resolution and site specificity, advancing RNA-targeted proteomics. Continued innovation in UAA-based chemistry promise to transform how RNA-protein complexes are interrogated and manipulated with molecular precision. Bifunctional ; Bioorthogonal chemistry ; Amino acid ; Limiting ; Interactome ; Genetic code ; Covalent bond Click Chemistry and Applications ; RNA and protein synthesis mechanisms ; Photochromic and Fluorescence Chemistry
Source: BSU- Journal of Chemistry and Material Sciences (article, 2025-01-01)
Field: Materials Science — Materials Chemistry

SYNTHESIS AND STRUCTURALCHARACTERIZATION OF SOLID SOLUTIONS IN THEGeBi2Te4–MnBi2Te4 AND GeBi4Te7–MnBi4Te7SYSTEMS This study reports the synthesis and comprehensive characterization of layered solid solutions in the GeBi2Te4-MnBi2Te4 and GeBi4Te7-MnBi4Te7 systems, which belong to the tetradymite family of compounds known for their thermoelectric and topological insulator properties.Alloys with varying Ge-Mn ratios were prepared using a two-stage thermal treatment involving melt quenching followed by prolonged annealing.Powder X-ray diffraction confirmed the formation of single-phase solid solutions across the full compositional range in both systems.A systematic shift in diffraction peaks with increasing Mn content indicates lattice parameter variation consistent with Vegard's law, reflecting the substitution of Ge 2+ by larger Mn 2+ ions.Le Bail refinement was employed to determine precise lattice parameters, revealing smooth trends without structural anomalies.Scanning electron microscopy further confirmed the microstructural homogeneity of the samples.The findings demonstrate the formation of continuous solid solutions in both systems, offering a basis for future exploration of their electronic and magnetic properties. Characterization (materials science) ; Materials science ; Nanotechnology Phase-change materials and chalcogenides ; Crystal Structures and Properties ; Chemical Thermodynamics and Molecular Structure
Authors: Erik J. Schulze | Mingjian Wu | Christian Hofmann | Erdmann Spiecker | Andreas Hirsch
Source: Chemistry - A European Journal (article, 2025-07-22)
Field: Materials Science — Materials Chemistry

Synthesis and Self‐Assembly of a Discotic Oligo‐Carboxylate <i>Tetra‐</i>Porphyrin‐Perylenebisimide Amphiphile We report the synthesis of an amphiphilic tetra-porphyrin perylenebisimide (PBI) conjugate via four-fold Suzuki cross-coupling at the PBI ortho-position. Oligo-carboxylate Newkome-type G1 dendrons attached at the porphyrin periphery serve as polar head groups. Theoretical modelling corroborated the assumed planar discotic geometry. The amphiphile is very soluble in mixtures of basic water and THF, where it displays strong aggregation at high water content. Insights into the self-assembly process were obtained by tracking the individualization through THF addition using UV/Vis absorption spectroscopy. Here, a PBI-centred aggregation motif becomes evident. Further evaluation of the morphology via STEM and TEM imaging reveals that the assembly is guided by hydrophobic interactions as well as interactions of the carboxylates. These ortho-linked tetra-porphyrin PBI architectures fill a gap within the known families of porphyrin-PBI conjugates. Furthermore, the amphiphile is a valuable addition to the library of amphiphilic porphyrin-PBI conjugates, representing a discotic counterpart to the known calamitic architectures. Porphyrin ; Amphiphile ; Carboxylate ; Chemistry ; Self-assembly ; Conjugate ; Materials science ; Polymer chemistry ; Photochemistry ; Combinatorial chemistry ; Stereochemistry ; Copolymer ; Organic chemistry ; Polymer Porphyrin and Phthalocyanine Chemistry ; Supramolecular Self-Assembly in Materials ; Luminescence and Fluorescent Materials
Authors: Jun Yang Ong | E. Meléndez | Tom Wennekes
Source: ChemRxiv (preprint, 2025-06-22)
Field: Chemistry — Organic Chemistry

Developing covalent affinity-based probes and inhibitors for sialyltransferases using a modular and direct-to-biology compatible chlorotriazine (ClTriZ) warhead platform Covalent chemical probes are powerful tools for protein profiling and inhibitor development, but their synthesis often poses significant challenges. Here, we introduce chlorotriazine (ClTriZ) as a novel covalent warhead that enables efficient and modular synthesis of covalent probes via a fully water compatible, “double-click” direct-to-biology (D2B) platform. The ClTriZ warhead displays a labelling rate of kL = (9.0 ± 0.3) x 10-5 s−1, comparable to the established ligand-directed chemistry warheads, and when integrated into the platform supports rapid generation and screening of covalent probes and inhibitors directly with recombinant proteins or in cell lysates without purification. Applying this platform, we identified proximity-induced, context-dependent probes that selectively label multiple targets, including avidin, cereblon (CRBN) and sialyltransferases. We focused further on sialyltransferases, using the platform to rapidly iterate and identify highly ligand-specific probes that selectively label the endogenous sialyltransferase Lst in live Neisseria gonorrhoeae. Notably, these ClTriZ probes also enabled the first reported irreversible inhibition of a sialyltransferase, PmST1, with kinact / KI = 56.2 ± 6.1 M-1 s-1, overcoming the lack of covalent intermediates in SN2/SNi catalytic mechanisms, characteristic of this enzyme class. Overall, our platform provides a versatile and high-throughput route to develop covalent probes and inhibitors, with broad potential across diverse glycosyltransferases and beyond to other protein families. Covalent bond ; Sialyltransferase ; Warhead ; Biochemistry ; Chemistry ; Computational biology ; Combinatorial chemistry ; Click chemistry ; Target protein ; Biology ; Enzyme Click Chemistry and Applications ; Glycosylation and Glycoproteins Research ; Chemical Synthesis and Analysis
Authors: Nilanjal Misra | Swarnima Rawat | Sweetie R. Kanatt | Shubhangi A. Shelkar | Anitta Rose Thomas | Ankita Pathak | Sanjay Kumar | Manish Singh | Virendra Kumar
Source: Scientific Reports (article, 2025-12-02)
Field: Materials Science — Surfaces, Coatings and Films

Plasma copolymerized oxazoline and fluoro monomer based amphiphilic coatings for antibacterial and antifouling applications Incorporation of antibacterial and antibiofouling properties into commercial fabrics is an attractive proposition considering its multifold applications in the health industry. However poor bacterial anti adhesion and low shelf-life limit their widespread applicability. Moreover, while antifouling at the liquid-solid can be addressed by hydrophilic properties, that at the air-solid interface demands hydrophobicity. This work reports the use of an indigenously developed low pressure plasma set-up to deposit amphiphilic coatings through simultaneous deposition of poly(2-ethyl-2-oxazoline) (2E2O) and 1 H,1 H,2 H,2 H-perfluorodecyl acrylate (PFDA). Plasma parameters: deposition time, power, gas and monomer flow rates were optimized and the samples characterized using FTIR, XPS, SEM-EDX, AFM and Contact Angle (CA) measurement techniques. Samples were observed to inhibit biofilm formation from the viable cell enumeration method, while their biocidal efficacy was also established through antibacterial tests performed as per ISO 22196:2011. These hybrid coatings have potential applications in the healthcare sector as efficient antibacterial and antibiofouling surfaces. Biofouling ; Amphiphile ; Monomer ; Oxazoline ; Polyester ; Adhesion ; Biofilm Surface Modification and Superhydrophobicity ; Marine Biology and Environmental Chemistry ; Polymer Surface Interaction Studies
Authors: Antonio Sabljić | Doris Crnčević | Alma Ramić | Matilda Šprung | Renata Odžak
Source: Pharmaceuticals (article, 2025-08-28)
Field: Chemistry — Organic Chemistry

Structure–Function Insights into Quinuclidine-3-One BisQACs: Synthesis, Modulation of Bacterial Resistance, Structure–Activity Relationship, and Biological Profiling <b>Background</b>: The increasing prevalence of antibiotic-resistant bacterial strains highlights the urgent need for new membrane-targeting antimicrobial agents. Bisquaternary ammonium compounds (bisQACs) have attracted attention for their ability to disrupt bacterial membranes more effectively than monoquaternary analogs. Quinuclidine, known for its health-beneficial properties, has previously been explored for monoQAC derivatization, but studies using natural scaffolds to generate bisQACs remain limited. <b>Methods</b>: Here, we synthesized twelve novel quinuclidine-based bisQACs, systematically varying alkyl chain and linker lengths to investigate structure-activity relationships. <b>Results:</b> Several compounds, including 2(QC<sub>16</sub>)<sub>3</sub>, 2(QC<sub>16</sub>)<sub>4</sub>, 2(QC<sub>14</sub>)<sub>6</sub>, and 2(QC<sub>16</sub>)<sub>6</sub>, exhibited strong activity against <i>Staphylococcus aureus</i> (including MRSA), <i>Listeria monocytogenes</i>, and <i>Escherichia coli</i>, with 2(QC<sub>16</sub>)<sub>6</sub> being the most potent (MICs 5-38 µM). While cytotoxicity was observed on human RPE1 and HEK293 cells, selectivity indices indicated a favorable therapeutic window relative to reference QACs. <b>Conclusions:</b> These compounds also inhibited biofilm formation and induced rapid bacterial killing through a membrane-disruptive mode of action. Molecular docking showed that alkyl chain and linker variations modulate binding to the QacR efflux regulator, revealing a lower potential for efflux-mediated resistance. Overall, quinuclidine-based bisQACs represent promising leads for potent, selectively active next-generation antimicrobials with a reduced likelihood of resistance development. Quinuclidine ; Profiling (computer programming) ; Computational biology ; Biology ; Chemistry ; Computer science ; Stereochemistry Chemical Synthesis and Reactions ; Antimicrobial agents and applications ; Environmental Chemistry and Analysis
Authors: Lorenzo Gualandi | Anna Turchetti | Paola Franchi | Lorenzo Sorace | Stephen M. Goldup | F. Canepa | G. Lamura | Marco Lucarini
Source: Chemistry - A European Journal (article, 2025-04-11)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Influence of Protonation and Iron(II) Complexation on Magnetic Interactions in Spin‐Labeled Mechanically Interlocked Molecules This study reports the effects of protonation and Fe(II) complexation on the exchange coupling and magnetic properties of a [2]-rotaxane and its corresponding free-axle biradicals. The rotaxane features nitronyl-nitroxide units as bulky stopper groups, a triazole-pyridine-triazole ligand as the axle component, and a bipyridine moiety within the macrocyclic ring. Our findings, obtained by Electron Paramagnetic Resonance spectroscopy in solution and magnetometry in solid state, demonstrate that rotaxanation and protonation induce profound changes in the magnetic interactions of the biradical both in its free form and as complexed with Fe(II). These results highlight the transformative impact of the mechanical bond on the electronic structure of interlocked radical systems. Rotaxane ; Protonation ; Chemistry ; Electron paramagnetic resonance ; Molecule ; Moiety ; Pyridine ; Crystallography ; Ligand (biochemistry) ; Photochemistry ; Triazole ; Stereochemistry ; Nuclear magnetic resonance ; Medicinal chemistry ; Organic chemistry Magnetism in coordination complexes ; Electron Spin Resonance Studies ; Lanthanide and Transition Metal Complexes
Authors: Siyuan Guo
Source: Applied and Computational Engineering (article, 2025-12-10)
Field: Materials Science — Polymers and Plastics

Sustainable and Environmentally Friendly Flame Retardants for Wood Materials Used in Construction Wood is a material that widely used in construction due to its strength, renewability, and natural appearance. However, its flammability poses significant fire safety challenges in buildings. Traditional flame retardants are effective at reducing fire risks but often introduce new environmental and health hazards, such as toxic smoke and persistent pollution. In response, recent research has focused on developing sustainable and eco-friendly flame retardants for wood. This paper reviews several categories of these newer solutions, including bio-based compounds derived from plants, fully degradable additives, and non-toxic inorganic materials. It examines how these substances work to protect wood by slowing ignition, promoting char formation, and creating physical barriers to flames. The paper also discusses different manufacturing and application methods, highlighting how they affect performance, cost, and real-world use. By comparing traditional and sustainable approaches, the study emphasizes the potential for safer, greener fire protection technologies to play a major role in future construction. Flammability ; Environmentally friendly ; Fire retardant ; Work (physics) ; Fire safety ; Smoke ; Human health ; Fire protection Flame retardant materials and properties ; Fire dynamics and safety research ; Natural Fiber Reinforced Composites