jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: L.A. Makarova | Michail T. Musaev | Margarita R. Kalandiia | S. A. Kostrov | Elena Yu. Kramarenko | Vitalii Salnikov | D. A. Gavrilov | Alexander Omelyanchik | Valeria Rodionova | N. S. Perov
Source: Polymers (article, 2025-04-26)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Enhancement of Magnetoelectric Effect in Layered Polymer Composites by Zn2+ and Ni2+ Substitution in CoFe2O4 Nanoparticles Two-layered structures consisting of piezopolymer and magnetic elastomer were investigated as magnetoelectric material. Three types of magnetic elastomer based on cobalt ferrite (CoFe<sub>2</sub>O<sub>4</sub>) and Ni- or Zn-substituted CoFe<sub>2</sub>O<sub>4</sub> nanoparticles were used as magnetically sensitive layers. Cobalt ferrite nanoparticles are considered one of the most promising metal-oxide nanomaterials because of their favorable magnetic properties, such as high saturation magnetization and magnetic anisotropy. The substitution of Co<sup>2+</sup> in cobalt ferrite with other transition metals allows for additional tailoring of these properties. The modified magnetic behavior of the substituted CoFe<sub>2</sub>O<sub>4</sub> nanoparticles directly influenced the magnetic properties of magnetic elastomers and, consequently, the magnetoelectric response of composite structures. In this case, the resonant frequency of the magnetoelectric effect remained largely independent of the type of magnetic nanoparticles in the magnetic elastomer layer but its magnitude increased upon Zn substitution up to ~107 mV·cm<sup>-1</sup>·Oe<sup>-1</sup>. These findings highlight the potential of chemically engineered magnetic properties of CoFe<sub>2</sub>O<sub>4</sub> nanoparticles for manufacturing magnetoelectric composites to expand their applications in energy harvesting and sensors. Materials science ; Substitution (logic) ; Composite material ; Nanoparticle ; Polymer ; Nanotechnology Multiferroics and related materials ; Ferroelectric and Piezoelectric Materials ; Magnetic Properties and Synthesis of Ferrites
Authors: Ayentika Sen | Aruna K. Mora | Soumitra Kundu | Sukhendu Nath
Source: ChemPhotoChem (article, 2025-02-19)
Field: Chemistry — Spectroscopy

Role of Ion‐Pair and H‐Bonding in Colorimetric Detection of Insulin Fibrils with Picomolar Sensitivity Abstract Ultrasensitive detection of amyloid fibril, a biomarker of several neurological diseases, has been achieved using a hemicyanine dye. Amyloid fibril induces a remarkable change in the absorption spectral position (~115 nm) of the perchlorate salt of the probe leading to a naked‐eye detection of these neurotoxic protein aggregates. Such a large shift in the absorption spectra has been utilised to develop a simple and cost effective paper based detection of insulin aggregates with a limit of detection (LOD) of less than 2 pM. Besides the changes in the absorption spectra, the emission intensity of the probe shows almost two orders of magnitude increase in the presence of insulin amyloid fibrils. Such dual sensing properties of the present hemicyanine molecule make it a noble probe for amyloid fibrils. Our detailed investigation on the fundamental mechanism responsible for the fibril‐induced spectral changes in the dye has established the role of amyloid induced dissociation of ion‐pair and solute‐solvent hydrogen bonding in the colorimetric detection of amyloid fibrils. Quantum chemical calculations and blind molecular docking studies have also been performed to strengthen our experimental observations. This result will open up a new frontier in the field of amyloid probes based on the unique mechanism proposed in this work. Sensitivity (control systems) ; Chemistry ; Fibril ; Ion ; Insulin ; Insulin sensitivity ; Biophysics ; Chromatography ; Biochemistry ; Medicine ; Internal medicine ; Biology ; Organic chemistry Analytical Chemistry and Chromatography ; Biochemical effects in animals ; Supramolecular Self-Assembly in Materials
Authors: M. Itō | Tomoko Fujino | Toshiki Higashino | Mafumi Hishida | Hatsumi Mori
Source: Angewandte Chemie International Edition (article, 2025-09-03)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Distinct Hole and Electron Transport Anisotropy in Ambipolar Nickel Dithiolene‐Based Semiconductor Understanding anisotropic charge transport in molecular semiconductors is crucial for device optimization, yet its intricate dependence on orbital-specific intermolecular interactions and molecular packing remains a challenge, especially in ambipolar systems. In ambipolar semiconductors, where both holes and electrons participate in conduction, distinct molecular orbitals prompt a critical inquiry: can orbital variations result in coexisting yet distinct anisotropic transport properties within a single component? We confirm this possibility by demonstrating that the air-stable nickel dithiolene, Ni(4OPr), exhibits such behavior. Despite its herringbone stacking implying a two-dimensional electronic structure, Ni(4OPr) uniquely exhibits distinct intermolecular interactions for hole (HOMO-to-HOMO; HOMO = highest occupied molecular orbital) and electron (LUMO-to-LUMO; LUMO = lowest unoccupied molecular orbital) transport. Crucially, this leads to highly anisotropic hole transport pathways, while electron pathways are remarkably isotropic, demonstrating a stark contrast in their transport anisotropies. Leveraging the high crystallinity, grazing-incidence wide-angle X-ray scattering (GIWAXS) determined in-plane molecular orientation. This enabled experimental verification of distinct anisotropic hole and electron transport, directly governed by orbital-specific intermolecular interactions, in an ambipolar molecular semiconductor. Our findings, demonstrating coexisting yet distinct anisotropic transport properties for both carriers within a single component, significantly advance the understanding of ambipolar molecular semiconductors and broaden their scope for future device applications. Ambipolar diffusion ; HOMO/LUMO ; Intermolecular force ; Chemical physics ; Molecular orbital ; Anisotropy ; Materials science ; Semiconductor ; Electron ; Condensed matter physics ; Chemistry ; Physics ; Molecule ; Optoelectronics ; Optics Organic and Molecular Conductors Research ; Molecular Junctions and Nanostructures ; Organic Electronics and Photovoltaics
Authors: Kyriaki Koupepidou | Alan C. Eaby | Debobroto Sensharma | Sousa Javan Nikkhah | Tao He | Matteo Lusi | Matthias Vandichel | Leonard J. Barbour | Soumya Mukherjee | Michael J. Zaworotko
Source: Angewandte Chemie (article, 2025-01-21)
Field: Materials Science — Materials Chemistry

A Needle in a Haystack: Transient Porosity in a Closed Pore Square Lattice Coordination Network Abstract Guest transport through discrete voids (closed pores) in crystalline solids is poorly understood. Herein, we report the gas sorption properties of a nonporous coordination network, {[Co(bib) 2 Cl 2 ] ⋅ 2MeOH} n ( sql‐bib‐Co‐Cl‐α ), featuring square lattice ( sql ) topology and the bent linker 1,3‐bis(1 H ‐imidazol‐1‐yl)benzene (bib). The as‐synthesized sql‐bib‐Co‐Cl‐α has 11.3 % (313 Å 3 ) of its unit cell volume in closed pores occupied by methanol (MeOH). Upon desolvation and air exposure, sql‐bib‐Co‐Cl‐α underwent a single‐crystal to single‐crystal (SC‐SC) phase transformation to sql‐bib‐Co‐Cl‐β′ , wherein MeOH was replaced by water. Activation (vacuum or N 2 flow) resulted in dehydration and retention of the closed pores, affording sql‐bib‐Co‐Cl‐β with 7.7 % (194 Å 3 ) guest‐accessible space. sql‐bib‐Co‐Cl‐β was found to preferentially adsorb C 2 H 2 (at 265 K) over CO 2 (at 195 K) through gate‐opening mechanisms, at gate‐opening pressures of 59.8 and 27.7 kPa, respectively, while other C2 gases were excluded. PXRD was used to monitor transformations between the three phases of sql‐bib‐Co‐Cl , while in situ DSC, in situ SCXRD under CO 2 pressure, and computational studies provided insight into the guest transport mechanism, which we attribute to the angular, flexible nature of the bib ligand. Further, the preferential adsorption of C 2 H 2 over CO 2 and other C2 gases suggests that transiently porous sorbents might have utility in separations. Haystack ; Porosity ; Transient (computer programming) ; Porous medium ; Materials science ; Chemistry ; Composite material ; Computer science Nanoporous metals and alloys ; Photonic Crystals and Applications ; Mesoporous Materials and Catalysis
Authors: Carmen Rosales-Martínez | Sousa Javan Nikkhah | Marcileia Zanatta | Juan Carlos Martínez | Matthias Vandichel | Isabel Abánades Lázaro
Source: Materials Horizons (article, 2025-01-01)
Field: Chemistry — Inorganic Chemistry

Multivariate modulation of Zr <sub>6</sub> UiO-66 for enhanced cooperative CO <sub>2</sub> adsorption through defect multi-functionalisation The multivariate modulation of MOFs allows for the simultaneous introduction of multiple functionalities at defect sites during synthesis, enhancing the MOF porosity. By the thoughtful choice of modulators' functionalities targeted at CO<sub>2</sub> adsorption, the designed dimodulated MOF, UiO-66-NH<sub>2</sub>/SO<sub>3</sub>, has a 6.6 mmol g<sup>-1</sup> CO<sub>2</sub> adsorption at 273 K and 1 bar, a 2.3-fold increase compared to the pristine MOF and a 1.6-fold enhancement compared to the single-modulated MOFs. This enhancement is due to the cooperative effect of functional units, which is supported by Monte Carlo simulations. Adsorption ; Modulation (music) ; Multivariate statistics ; Materials science ; Metal-organic framework ; Chemical engineering ; Chemistry ; Acoustics ; Mathematics ; Physical chemistry ; Physics ; Statistics ; Engineering Metal-Organic Frameworks: Synthesis and Applications ; Covalent Organic Framework Applications ; Catalytic Processes in Materials Science
Authors: Abu Bakar Siddique | Isabella Gonzalez | Subhro Kundu | E. Martı́nez | Sergio O. Martínez‐Chapa | Marc Madou | Mallar Ray
Source: Advanced Materials Interfaces (article, 2025-08-05)
Field: Materials Science — Materials Chemistry

Eco‐Friendly N, S Co‐Doped Graphene Quantum Dots for Sensing 3‐Nitro‐L‐Tyrosine via Dark State Formation: Evidence From Photoluminescence and Single‐Particle Spectroscopy Abstract 3‐Nitro‐L‐tyrosine (3NT) is a key biomarker of oxidative stress associated with neurodegenerative and cardiovascular diseases. Here, we report a selective optical sensing strategy based on photoluminescence (PL) quenching of nitrogen and sulfur co‐doped graphene quantum dots (NS‐GQDs) synthesized from garlic, a natural and sustainable precursor. PL quenching by 3NT is driven by static interactions, as revealed by single‐particle near‐field IR spectroscopy. Time‐dependent density functional theory indicates that complexation with 3NT induces a significant reduction in the oscillator strength of key excited states in the NS‐GQDs, suppressing radiative transitions and suggesting the formation of a non‐emissive “dark states”. This interaction creates an unambiguous optical fingerprint for 3NT, enabling highly selective molecular recognition. Our findings establish a mechanistic blueprint for the rational design of biocompatible carbon‐based nanomaterials for next‐generation sensing platforms. Materials science ; Photoluminescence ; Quantum dot ; Graphene ; Spectroscopy ; Nitro ; Doping ; Particle (ecology) ; Nanotechnology ; Optoelectronics ; Analytical Chemistry (journal) ; Quantum mechanics ; Physics ; Organic chemistry ; Chemistry Carbon and Quantum Dots Applications ; Graphene and Nanomaterials Applications ; Nanocluster Synthesis and Applications
Authors: Priyanka Dubey | Arif Somani | Jessica Lin | Anthony T. Iavarone | Judith P. Klinman
Source: bioRxiv (Cold Spring Harbor Laboratory) (preprint, 2025-01-29)
Field: Materials Science — Materials Chemistry

Identification of Scaffold Specific Energy Transfer Networks in the Enthalpic Activation of Orotidine 5’-Monophosphate Decarboxylase Orotidine 5'-monophosphate decarboxylase (OMPDC) is one of the most efficient enzyme systems studied, enhancing the decarboxylation of OMP to uridine 5'-monophosphate (UMP) by ca. 17 orders of magnitude, primarily by reducing the enthalpy of activation by ca. 28 kcal/mol. Despite a substantial reduction in activation enthalpy, OMPDC requires 15 kcal/mol of activation energy post-ES complex formation. This study investigates the physical basis of how thermal energy from solvent collisions is directed into the active site of enzyme to enable efficient thermal activation of the reaction. Comparative study of temperature-dependent hydrogen-deuterium exchange mass spectrometry (TDHDX) for WT and mutant forms of enzymes has recently been shown to uncover site specific protein networks for thermal energy transfer from solvent to enzyme active sites. In this study, we interrogate region-specific changes in the enthalpic barrier for local protein flexibility using a native OMPDC from <i>Methanothermobacter thermautotrophicus</i> (Mt-OMPDC) and a single site variant (Leu123Ala) that alters the activation enthalpy for catalytic turnover. The data obtained implicate four spatially resolved, thermally sensitive networks that originate at different protein/solvent interfaces and terminate at sites surrounding the substrate near the substrate phosphate-binding region (R203), the substrate- ribose binding region (K42), and a reaction enhancing loop5 (S127). These are proposed to act synergistically, transiently optimizing the position and electrostatics of the reactive carboxylate of the substrate to facilitate activated complex formation. The uncovered complexity of thermal activation networks in Mt-OMPDC distinguishes this enzyme from other members of the TIM barrel family previously investigated by TDHDX. The new findings extend the essential role of protein scaffold dynamics in orchestrating enzyme activity, with broad implications for the design of highly efficient biocatalysts. Chemistry ; Active site ; Activation energy ; Substrate (aquarium) ; Activated complex ; Stereochemistry ; Enthalpy ; Enzyme ; Biochemistry ; Physical chemistry ; Kinetics ; Thermodynamics ; Reaction rate constant Enzyme Structure and Function ; Biochemical and biochemical processes ; Protein Structure and Dynamics
Authors: Toufik Mahamdi | Nadia Moltó | Mireia Arasa | Roger Giné | Jordi Rofes | María García‐Altares | María Vinaixa | Óscar Yanes
Source: bioRxiv (Cold Spring Harbor Laboratory) (preprint, 2025-06-27)
Field: Chemistry — Spectroscopy

Solid Ionic Matrices applied via Low-Temperature Evaporation enable High-Resolution and Sensitive MALDI Imaging of Metabolites Abstract Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry Imaging (MALDI-MSI) has become a key technology for spatially resolved molecular analysis. However, imaging of low molecular weight compounds remains challenging due to spectral interferences in the low m/z range caused by conventional organic matrices. Ionic matrices (IMs), in contrast, reduce matrix-related background signals, improve spectral reproducibility, and enhance sensitivity for detecting metabolites and lipids, but their use in MALDI-MSI has so far been limited, primarily focusing on lipid imaging above m/z 500. Here, we present a novel approach combining solid ionic matrices (ISMs) with low-temperature thermal evaporation (LTE) to enhance MALDI-MSI performance for small metabolites. ISMs based on α-cyano-4-hydroxycinnamic acid (CHCA) and 2,5-dihydroxybenzoic acid (DHB) provided superior sensitivity, with CHCA + N,N-diethylaniline enabling the detection and annotation of 73 small metabolites ( m/z &lt;500) in mouse brain at 20 µm spatial resolution. When applied to the pancreas, this matrix enabled the first specific localization of melatonin and 3-iodotyrosine within the islets of Langerhans, opening new avenues for spatial metabolomics in endocrine research. Evaporation ; Chemistry ; MALDI imaging ; Resolution (logic) ; Low resolution ; Chromatography ; Ionic bonding ; Analytical Chemistry (journal) ; High resolution ; Ion ; Matrix-assisted laser desorption/ionization ; Organic chemistry ; Computer science ; Desorption ; Physics ; Adsorption ; Remote sensing ; Artificial intelligence ; Thermodynamics Mass Spectrometry Techniques and Applications ; Analytical chemistry methods development ; Analytical Chemistry and Chromatography
Authors: Na‐Kyung Lee | Hyeon-Sik Ahn | Min-Sang Kim | Seungseo Park | Yoonseuk Choi
Source: Scientific Reports (article, 2025-02-13)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Guest-host liquid crystal polarizer for electrically switchable polarization in CCTV systems This study proposes a liquid crystal-based polarizer system using guest-host liquid crystals (GHLC) doped with dichroic dye, which enables switching between polarization and normal CCTV modes. The GHLC polarizer overcomes the limitation of reduced light transmittance in low-light conditions, a common drawback of conventional polarizing filters. The system leverages the dielectric anisotropy of liquid crystals and the absorption anisotropy of the dye and enables electrical modulation of transmittance by adjusting the polarization orientation. This functionality facilitates switching between polarization and normal modes, contingent on the amount of light reflected from the subject, thereby ensuring real-time adaptability across diverse lighting environments. Furthermore, the system sustains optimal CCTV performance without necessitating physical intervention, offering enhanced flexibility and efficiency compared with conventional polarizing filter systems. Polarizer ; Polarization (electrochemistry) ; Liquid crystal ; Host (biology) ; Materials science ; Optoelectronics ; Computer science ; Optics ; Chemistry ; Physics ; Biology ; Birefringence Liquid Crystal Research Advancements ; Advanced Antenna and Metasurface Technologies
Authors: Saheb Bera | Diksha Kaushik | Hemant Kumar
Source: Communications Engineering (article, 2025-11-13)
Field: Materials Science — Materials Chemistry

MXene alloy-based metal-semiconductor contact for low-resistive field-effect transistors MXenes offer a unique platform for designing high-performance electronic devices due to their diverse properties and chemical tunability. This study focuses on engineering low-resistance metal-semiconductor contacts using MXenes for future field-effect transistor applications. Through a comprehensive approach combining first-principles calculations, transport simulations, and alloy phase engineering, we demonstrate the feasibility of achieving low-resistance contacts with high current-carrying capacity. Through first-principles calculations, we identify promising MXene heterojunctions based on lattice matching and Schottky barrier height. Notably, the Ta<sub>2</sub>CO<sub>2</sub>-Ti<sub>2</sub>CO<sub>2</sub> contact exhibits a remarkably low Schottky barrier height. Using non-equilibrium Green's function calculations, we demonstrate high output current in this contact, indicating low resistance. Further analysis reveals the critical role of carrier density and detrimental impact of metal-induced gap states. To suppress metal-induced gap states, we propose an interfacial alloying strategy using a Ta<sub>2x</sub>Ti<sub>2(1-x)</sub>CO<sub>2</sub> solid solution, which reduces interfacial charge transfer and promotes smoother electronic coupling. This, in turn, reduces the Fermi-level pinning effect and contributes to a substantial reduction in contact resistance across the MXene interface. This study highlights the potential of MXenes as building blocks for advanced electronics and provides a pathway for engineering high-performance contacts through a combined computational and design approach. MXenes ; Schottky barrier ; Electronics ; Transistor ; Schottky diode ; Heterojunction ; Contact resistance MXene and MAX Phase Materials ; 2D Materials and Applications ; Electromagnetic wave absorption materials
Authors: Eveline H. Tiekink | Matthijs W. Kragtwijk | Trevor A. Hamlin
Source: ChemRxiv (preprint, 2025-04-23)
Field: Chemistry — Organic Chemistry

Small Molecule Activation by Metallylenes and Their Follow-up Reactions The activation of small molecules is a crucial step in advancing sustainable chemistry, enabling key transformations in fine chemical synthesis and energy storage. While transition metals have traditionally dominated this field, main-group elements—specifically metallylenes, which are heavier analogs of carbenes (silylenes, germylenes, stannylenes, and plumbylenes)—have emerged as viable alternatives due to their unique electronic properties and tunable reactivity. This review explores the mechanisms by which metallylenes activate small molecules, highlighting the influence of ligand design, electronic structure, and geometric factors. We discuss recent advances in the field, including computational insights into metallylene-mediated bond activation and experimental demonstrations of their catalytic potential. Additionally, we examine follow-up reactions such as hydrogenation and hydroboration, which illustrate the versatility of metallylenes in small-molecule transformation. By providing a comprehensive overview of the latest developments, this review aims to bridge fundamental principles with potential applications, paving the way for metallylene-based catalysis in sustainable chemistry. Chemistry Inorganic and Organometallic Chemistry ; Catalytic Cross-Coupling Reactions ; Organometallic Complex Synthesis and Catalysis
Authors: A. Silva | Maria F. Martins | Carlos B. P. Oliveira | José A. Martins | Paula M. T. Ferreira | Maria João R.P. Queiroz
Source: Molecules (article, 2025-02-14)
Field: Materials Science — Biomaterials

Synthesis of S- and N,S-Heterocycle–Dipeptide Conjugates for Supramolecular Hydrogel Formation Small peptides with aromatic nuclei at the <i>N</i>-terminus have been shown to form bioactive, biocompatible, and biodegradable supramolecular peptide hydrogels. Novel heterocycle-dipeptide conjugates with potential biological activity or application as drug carriers were synthesized by using <i>S-</i>(benzo[<i>b</i>]thiophene) and <i>N</i>,<i>S-</i>(thieno [2,3-<i>b</i>]pyridine and thieno[2,3-<i>b</i>]quinoline) heterocycles as <i>N</i>-protective groups for dipeptides l-Phe-l-Phe and l-Phe-l-Leu. The synthesis involved coupling heterocyclic carboxylic acids with trifluoroacetate salts of ethyl l-phenylalanyl-l-phenylalaninate and ethyl l-phenylalanyl- l-leucinate using HBTU and Et<sub>3</sub>N, producing the corresponding six <i>N</i>-heterocycle-dipeptide ester conjugates, which were then hydrolyzed to the carboxylic acids. These conjugates were subjected to gelation tests in water starting from 0.4 wt% concentration of the conjugates, using a pH-lowering method with GdL. Among them, only the conjugate of benzo[<i>b</i>]thiophene with l-Phe-l-Phe-OH formed a hydrogel, with a gelation critical concentration of 0.15 wt% (GdL 0.6%) and a final pH of 6.8, which is important for biological applications. The hydrogel was characterized by STEM, revealing nanofibers with an average thickness of 17 nm that assemble into a 3D network capable of trapping water. Further rheological analysis demonstrated its viscoelastic behavior (G' = 3.03 × 10<sup>3</sup> Pa; G″ = 3.28 × 10<sup>2</sup> Pa), comparable to the extracellular matrix of certain human tissues, crucial for biomedical applications. Dipeptide ; Conjugate ; Supramolecular chemistry ; Chemistry ; Stereochemistry ; Combinatorial chemistry ; Crystallography ; Peptide ; Crystal structure ; Biochemistry ; Mathematics Supramolecular Self-Assembly in Materials ; Polydiacetylene-based materials and applications ; Photochromic and Fluorescence Chemistry