jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Liam E. Claton | Hongjun Pan | Eric E. Simanek
Source: The Journal of Organic Chemistry (article, 2024-04-09)
Field: Chemistry — Organic Chemistry

Impact of Solvent and Protonation State on Rotational Barriers in [s]-Triazines Amine-substituted [s]-triazines display hindered rotation around the triazine-N bond. While this barrier, Δ<i>G</i><sup>‡</sup>, has been measured to be between 15.1 and 17.7 kcal/mol for neutral triazines, the impacts that solvent and protonation state have not been addressed. Using a dimethylamine substituent as a reporter, Δ<i>G</i><sup>‡</sup> was measured to be 17.5-19.3 kcal/mol upon protonation across a range of solvents (D<sub>2</sub>O, DMSO-<i>d</i><sub>6</sub>, MeCN-<i>d</i><sub>3</sub>, MeOD-<i>d</i><sub>4</sub>, tetrahydrofuran-<i>d</i><sub>8</sub>, trifluoroethanol-<i>d</i><sub>3</sub>). Furthermore, Δ<i>G</i><sup>‡</sup> increases as the solvent dielectric decreases (<i>p</i> < 0.01). This trend is consistent with the role that solvent plays in stabilizing the increased charge density on the triazine ring resulting from a loss of conjugation with the dimethylamine substituent. Across these solvents, Δ<i>G</i><sup>‡</sup> for the neutral molecule is smaller by ∼2-3 kcal/mol, ranging from 15.3-16.1 kcal/mol. In pyridine, Δ<i>G</i><sup>‡</sup> does not correlate with the solvent dielectric for the "protonated" model. The lower barrier is attributed to competitive protonation: the p<i>K</i><sub>a</sub> of the protonated triazine (∼6) is similar to that of protonated pyridine-<i>d</i><sub>5</sub> (5.8). As additional acid is added, Δ<i>G</i><sup>‡</sup> increases. Adding additional acid to the protonated model in D<sub>2</sub>O or DMSO-<i>d</i><sub>6</sub> does not significantly affect Δ<i>G</i><sup>‡</sup>. Chemistry ; Protonation ; Dimethylamine ; Substituent ; Pyridine ; Solvent ; Solvent effects ; Photochemistry ; Amine gas treating ; Medicinal chemistry ; Molecule ; Organic chemistry Synthesis and Characterization of Heterocyclic Compounds ; DNA and Nucleic Acid Chemistry ; Chemical Reaction Mechanisms
Authors: Steen H. Hansen | Christian D. Buch | Stergios Piligkos
Source: Inorganic Chemistry Frontiers (article, 2024-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Structural isomerism-tuned magnetisation relaxation dynamics in lanthanide coordination complexes Control of the composition of molecular magnetic materials by chemical modification leads to tuning of their magnetization dynamics. We show that two structural isomers display such differences with respect to each other and to their parent complex. Lanthanide ; Magnetization ; Relaxation (psychology) ; Dynamics (music) ; Magnetization dynamics ; Materials science ; Molecular dynamics ; Chemical physics ; Chemistry ; Nuclear magnetic resonance ; Crystallography ; Physical chemistry ; Computational chemistry ; Physics ; Organic chemistry ; Ion ; Psychology Magnetism in coordination complexes ; Lanthanide and Transition Metal Complexes ; Electron Spin Resonance Studies
Authors: S. Sangeethavanathi | P. Gowthaman | S. Vigneswaran | M. Sathishkumar
Source: Material Science Research India (article, 2024-08-31)
Field: Materials Science — Materials Chemistry

Exploring the Structural, Optical and Surface Area Properties of Mos2 Nanoparticles This study delves into the development and characterization of MoS2 nanoparticles, employing a hydrothermal approach. The synthesized MoS2 nanoparticles underwent comprehensive analysis utilizing various analytical techniques such as X-ray Diffraction (XRD), Raman spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray spectroscopy (EDX), UV-Visible spectroscopy, and BET surface analysis. XRD analysis revealed the presence of a hexagonal phase structure with a crystallite size of 13 nm, indicating the nanoscale nature of the synthesized material. RAMAN spectroscopy confirmed the presence of characteristic peaks corresponding to Mo and S, validating the composition of the composites. FESEM images shows that the formation of flake like morphology and EDX affirmed the presence of Mo and S elements with the absence of other impurities, ensuring the purity of the MoS2 nanoparticles. UV-visible spectroscopy exhibited an energy band gap of 2.37 eV, suggesting potential applications in optoelectronic devices. BET surface area analysis revealed a surface area of 80 m²/g, indicative of the high surface area of the composites, which may enhance their reactivity and performance in various applications. These findings contribute to the understanding of MoS2 nanoparticles and their potential utilization in fields such as solar cell, catalysis, sensing, and energy storage. Materials science ; Nanoparticle ; Surface (topology) ; Nanotechnology ; Geometry ; Mathematics 2D Materials and Applications ; Chalcogenide Semiconductor Thin Films ; Quantum Dots Synthesis And Properties
Authors: Robin Petit | Resül Özdemir | Hannes Van Avermaet | Luca Giordano | Jakob Kuhs | Andreas Werbrouck | Matthias Filez | Jolien Dendooven | Zeger Hens | Philippe F. Smet | Christophe Detavernier
Source: ACS Applied Materials & Interfaces (article, 2024-11-08)
Field: Materials Science — Materials Chemistry

Atomic Layer Deposition for Stable InP-Based On-Chip Quantum Dot microLEDs: Hybrid Quantum Dot Pockets Recent advances in synthesis techniques yield InP-based QDs with optical properties comparable to those of benchmark Cd-based QDs, making InP-based QDs viable alternatives to toxic Cd-based QDs for applications such as quantum dot LEDs (QLEDs). However, QLEDs typically suffer from a loss of luminescence over time due to exposure of the QDs to ambient air. To avoid this, state-of-the-art hybrid barrier layers are explored consisting of alternating organic/inorganic layers. In this study, InP-based QD thin films and InP-based QDs embedded in Kraton polymers are encapsulated with a thin metal oxide barrier layer by atomic layer deposition (ALD). Specifically, Al<sub>2</sub>O<sub>3</sub>, TiO<sub>2</sub>, and ZnO thin films are deposited using trimethylaluminum (TMA), tetrakis(dimethylamino)titanium (TDMAT), and diethylzinc (DEZ), with H<sub>2</sub>O as the reactant. In situ photoluminescence (PL) is used to evaluate the optical response of the InP-based QDs during the ALD coating. The results show that ALD on pristine QD thin films causes degradation of luminescence, while this is not observed for polymer-embedded QDs. The long-term stability of the (ALD-coated) samples is investigated by accelerated degradation in a humidity chamber at a high temperature. Using a single Al<sub>2</sub>O<sub>3</sub> ALD thin film as a capping layer for polymer-embedded QDs, greater stability of the QD-PL over a period of at least 300 h is found compared to pristine QD samples. A similar study is performed with InP-based QDs embedded in UV-patterned polymer (thiol-ene) structures, the so-called QD pockets, envisioned for use in on-chip quantum dot microLEDs. These QD pockets are purposefully designed for pick-and-place operations to reduce the complexity of the on-chip quantum dot microLED manufacturing process. The PL stability was significantly improved after incorporating Al<sub>2</sub>O<sub>3</sub> ALD thin films, with these hybrid QD pockets showing no clear signs of degradation after 140 h. The combination of polymer embedding and ALD with the merits and scalability of the QD pocket structure is demonstrated to be an effective approach to improving the long-term QD stability and shows promise for the development of stable, InP-based on-chip quantum dot microLEDs. Quantum dot ; Materials science ; Atomic layer deposition ; Layer (electronics) ; Optoelectronics ; Nanotechnology ; Deposition (geology) ; Chip Quantum Dots Synthesis And Properties ; Nanowire Synthesis and Applications ; Semiconductor Quantum Structures and Devices
Authors: Aboudramane Koné | Souleymane Coulibaly | Mabintou Kalo | Camara Tchambaga Etienne | Sylvain Collet | Drissa Sissouma
Source: Synthetic Communications (article, 2024-12-18)
Field: Chemistry — Organic Chemistry

Synthesis of novel benzimidazole-based retrochalcones and their anticancer activity against breast and colon cancer International audience Chemistry ; Benzimidazole ; Paclitaxel ; Cancer ; Cell culture ; Pharmacology ; Cancer cell lines ; Stereochemistry ; IC50 ; Cancer research ; In vitro ; Cancer cell ; Combinatorial chemistry ; Biochemistry ; Internal medicine ; Organic chemistry ; Medicine Synthesis and biological activity ; Synthesis of Organic Compounds ; Bioactive Compounds and Antitumor Agents
Authors: María Jimena Salgueiro | Mariano Rodríguez | Fiorella Tesán | Melisa B. Nicoud | Vanina A. Medina | Marcela A. Morettón | Diego A. Chiappetta | Marcela Zubillaga
Source: EJNMMI Radiopharmacy and Chemistry (article, 2024-10-29)
Field: Materials Science — Biomaterials

Design and development of nanoprobes radiolabelled with 99mTc for the diagnosis and monitoring of therapeutic interventions in oncology preclinical research Soluplus<sup>®</sup>-based polymeric micelles provide a promising nanotechnological platform for the development of RNPs. The functionalization with glucose and bevacizumab enhances tumor specificity enabling effective imaging and monitoring of cancer in animal models. Psychological intervention ; Medicine ; Precision oncology ; Medical physics ; Intensive care medicine ; Oncology ; Internal medicine ; Cancer ; Nursing Nanoparticle-Based Drug Delivery ; Radiopharmaceutical Chemistry and Applications ; Nanoplatforms for cancer theranostics
Authors: Elnaz Zeinali | Yoshi W. Marien | Mariya Edeleva | Sean R. George | Michael F. Cunningham | Dagmar D’hooge | Paul Van Steenberge
Source: Reaction Chemistry & Engineering (article, 2024-01-01)
Field: Chemistry — Organic Chemistry

Comparing SG1 and TEMPO for NMP of <i>n</i>-butyl acrylate in miniemulsion to optimize the average particle size for rate and molecular control The interplay between compartmentalization and phase transfer effects in NMP of n -butyl acrylate in miniemulsion. Optimal average particle sizes are identified for the two most important nitroxides and different reaction conditions. Miniemulsion ; Acrylate ; Butyl acrylate ; Particle (ecology) ; Particle size ; Polymer chemistry ; Phase (matter) ; Compartmentalization (fire protection) ; Chemistry ; Materials science ; Copolymer ; Polymerization ; Organic chemistry ; Physical chemistry ; Polymer ; Biology Surfactants and Colloidal Systems ; Advanced Polymer Synthesis and Characterization ; Electron Spin Resonance Studies
Authors: Jelena Spasojević | Milica Milošević | Sašenka Vidičević | Jelena Tasić | Petar Milovanović | Marija Djurić | Dragan Ranković | Zorica Kačarević‐Popović | Аleksandra Radosavljević
Source: Polymers (article, 2024-11-19)
Field: Materials Science — Polymers and Plastics

Multifunctional Ag-Poly(N-isopropylacrylamide/itaconic Acid) Hydrogel Nanocomposites Prepared by Gamma Irradiation for Potential Application as Topical Treatment Dressings Today, hydrogel dressings that can protect injury sites and effectively promote healing have become highly desirable in wound management. Therefore, multifunctional silver-poli(<i>N</i>-isopropylacrylamide/itaconic acid) (Ag-P(NiPAAm/IA)) hydrogel nanocomposites were developed for potential application as topical treatment dressings. The radiolytic method, used for the crosslinking of the polymer matrix as well as for the in situ incorporation of silver nanoparticles (AgNPs) into the polymer matrix, enables the preparation of hydrogel nanocomposites without introducing harmful and toxic agents. Moreover, materials produced using γ-irradiation are simultaneously sterilized, thus fulfilling one of the basic requirements regarding their potential biomedical applications. The NiPAAm/IA ratio and the presence of AgNPs influenced the microstructural parameters of the investigated systems. Increasing the IA content leads to the formation of a more porous polymer matrix with larger pores, while the incorporated AgNPs act as additional junction points, decreasing the porosity and pore size of the resulting nanocomposite hydrogels. Swelling studies showed that most investigated systems uptake the fluids from their surroundings by non-Fick diffusion. Further, the Ag<sup>+</sup> ion release, antibacterial activity, and cytotoxicity of Ag-P(NiPAAm/IA) hydrogel nanocomposites were examined to evaluate their biomedical potential. All hydrogel nanocomposites showed an initial burst release of Ag<sup>+</sup> ions (useful in preventing bacteria adherence and biofilm formation), followed by a slower release of the same (ensuring sterility for longer use). An antibacterial activity test against <i>Escherichia coli</i> and <i>Staphylococcus aureus</i> showed that Ag-P(NiPAAm/IA) hydrogel nanocomposites, with silver concentrations around 10 ± 1 ppm, successfully prevent bacterial growth. Finally, it was shown that the investigated hydrogel nanocomposites do not exhibit a cytotoxic effect on human keratinocyte HaCaT cells. Therefore, these multifunctional hydrogel nanocomposites may promote wound repair and show promising potential for application as functional wound dressing. Itaconic acid ; Poly(N-isopropylacrylamide) ; Gamma irradiation ; Nanocomposite ; Materials science ; Irradiation ; Polymer chemistry ; Self-healing hydrogels ; Swelling ; Copolymer ; Nuclear chemistry ; Chemistry ; Nanotechnology ; Polymer ; Composite material Polymer Nanocomposite Synthesis and Irradiation ; Bone Tissue Engineering Materials ; Graphene and Nanomaterials Applications
Authors: Manon Jouanlanne | Antoine Egelé | Wiebke Drenckhan | Jean Farago | Aurélie Hourlier‐Fargette
Source: Macromolecular Rapid Communications (article, 2024-06-29)
Field: Materials Science — Polymers and Plastics

Solidification of Polyurethane Model Foams via Catalyst Drainage from a Secondary Foam Due to their unique mechanical and thermal properties, polyurethane foams are widely used in multiple fields of applications, including cushioning, thermal insulation or biomedical engineering. However, the way polyurethane foams are usually manufactured - via chemical foaming - produces samples where blowing and gelling occur at the same time, resulting in a morphology control achieved by trial and error processes. Here, a novel strategy is introduced to build model homogeneous polyurethane foams of controlled density with millimetric bubbles from liquid templates. By producing a polyurethane foam via physical bubbling without a catalyst and gently depositing a secondary foam containing catalyst on the top of this first foam, it is possible to take advantage of drainage mechanisms to trigger the solidification of the bottom foam. The characterization of the samples performed by X-ray microtomography allows to study quantitatively the structure of the final solid foam, at the global and at the local scale. Using the tomographic 3D images of the foam architectures, the superimposed foam technique introduced in this article is shown to be promising to produce foams with a good homogeneity along the vertical direction, with a density controlled by varying the concentration of catalyst in the secondary foam. Polyurethane ; Materials science ; Cushioning ; Homogeneity (statistics) ; Blowing agent ; Composite material ; Thermal insulation ; Metal foam ; Syntactic foam ; Thermal ; Catalysis ; Aluminium ; Layer (electronics) ; Chemistry Polymer composites and self-healing ; Pickering emulsions and particle stabilization ; Enhanced Oil Recovery Techniques
Authors: Diana Priyadarshini | Changbai Li | Rebecka Rilemark | Tobias Abrahamsson | Mary J. Donahue | Xenofon Strakosas | Fredrik Ek | Roger Olsson | Chiara Musumeci | Simone Fabiano | Magnus Berggren | Eva Olsson | Daniel T. Simon | Jennifer Y. Gerasimov
Source: Advanced Electronic Materials (article, 2024-11-21)
Field: Materials Science — Polymers and Plastics

Tuning the Organic Electrochemical Transistor (OECT) Threshold Voltage with Monomer Blends Abstract A novel approach is introduced to modulate the threshold voltage of organic electrochemical transistors (OECTs) that are fabricated by electropolymerizing the channel material between the source and drain electrodes. To achieve this, we adjust the ratio of two water‐soluble tri‐thiophene monomers, which share the same backbone, but present either anionic or zwitterionic sidechains, during channel formation. This approach allows for a continuous modulation of both the electropolymerization onset potential and the native doping state of the film. We attribute the effect of monomer blends displaying properties that are a weighted average of their components to the formation of nanoscale monomer aggregates that have a uniform internal charge density. Through an investigation of monomer aggregation behavior, polymer film growth, and device properties of OECTs fabricated by electropolymerization, we highlight the importance of monomer aggregation in the electropolymerization of conducting polymers. The ability to tune both electropolymerization onset and the OECT threshold voltage has significant implications for the development of more complex circuits for integrated neuromorphic computing, biosensing, and bioelectronic systems. Materials science ; Monomer ; Conductive polymer ; Electrochemistry ; Polymer ; Bioelectronics ; Nanotechnology ; Electrode ; Transistor ; Threshold voltage ; Biosensor ; Voltage ; Chemistry ; Composite material ; Electrical engineering Conducting polymers and applications ; Advanced Memory and Neural Computing ; Perovskite Materials and Applications
Authors: Vadakkalur Sampath Chithra | Selvam Prabu | G.P. Babu | Thamodharan Viswanathan | Ezhumalai David | Kalidoss Logesh | Nallasamy Palanisami
Source: ChemistrySelect (article, 2024-02-02)
Field: Materials Science — Electronic, Optical and Magnetic Materials

AIE‐Active Ferrocene Appended Linear (D‐π‐A) Aromatic Ester Chromophores: Structural, Theoretical and Effect on Phenyl Ring on Luminescence and Nonlinear Optical Properties Abstract In the present research, a new ferrocene‐appended linear donor‐π‐acceptor (D‐π‐A) ester chromophore Fc‐(C 6 H 4 ) 2 ‐COOC 2 H 5 ( 2 ) was synthesized and characterized using various spectroscopic techniques. The molecular structure of chromophore 2 was determined using single‐crystal X‐ray diffraction analysis, revealing its crystallization in the monoclinic crystal system with the P21/n space group. The chromophore Fc‐C 6 H 4 ‐COOC 2 H 4 ( 1 ) was utilized to compare its photophysical and nonlinear optical characteristics with those of 2 . Cyclic voltammetry revealed a single‐electron transfer mechanism from Fe 2+ ↔Fe 3+ . The emission solvatochromism studies show a polarized excited state in response to increasing solvent polarity, indicating charge transfer processes. Interestingly, in mixed aqueous media (THF/H 2 O), the chromophores exhibit intensified fluorescence due to restricted intra‐molecular rotation (RIR), despite weak emission in THF solvent. Chromophore 2 demonstrated 1.5 times higher second harmonic generation (SHG) efficiency than 1 , attributed to its extended π‐conjugation from an additional phenyl ring and reduced antiparallel alignments. Despite its centrosymmetric crystal packing, chromophore 2 exhibited SHG efficiency due to non‐covalent interactions (C−H⋅⋅⋅π) in the crystal lattice. Density Functional Theory (DFT) calculations, employing various functionals, provided insights into dipole moment and first hyperpolarizability, with B3LYP‐hybrid functional underestimating hyperpolarizability values owing to long‐range charge transfer interactions within the D‐π‐A systems, aligning closely with experimental findings. Hyperpolarizability ; Chromophore ; Solvatochromism ; Density functional theory ; Chemistry ; Ferrocene ; Photochemistry ; Excited state ; Second-harmonic generation ; Crystallography ; Polarizability ; Computational chemistry ; Molecule ; Physical chemistry ; Organic chemistry ; Optics Nonlinear Optical Materials Research ; Luminescence and Fluorescent Materials ; Molecular Sensors and Ion Detection
Authors: JuYeon Lee | Giselle Soares | Calvin Doty | Joonhyuck Park | Jack Hovey | Alex W. Schrader | Hee‐Sun Han
Source: ACS Applied Materials & Interfaces (article, 2024-03-12)
Field: Materials Science — Materials Chemistry

Versatile Prepolymer Platform for Controlled Tailoring of Quantum Dot Surface Properties Quantum dots (QDs) hold immense promise for bioimaging, yet technical challenges in surface engineering limit their wider scientific use. We introduce poly(pentafluorophenyl acrylate) (PPFPA) as a user-friendly prepolymer platform for creating precisely controlled multidentate polymeric ligands for QD surface engineering, accessible to researchers without extensive synthetic expertise. PPFPA combines the benefits of both bottom-up and prepolymer approaches, offering minimal susceptibility to hydrolysis and side reactions for controlled chemical composition, along with simple synthetic procedures using commercially available reagents. Live cell imaging experiments highlighted a significant reduction in nonspecific binding when employing PPFPA, owing to its minimal hydrolysis, in contrast to ligands synthesized by using a conventional prepolymer prone to uncontrolled hydrolysis. This observation underscores the distinct advantage of our prepolymer system. Leveraging PPFPA, we synthesized biomolecule-conjugated QDs and performed QD-based immunofluorescence to detect a cytosolic protein. To effectively label cytosolic targets in such a dense and complex environment, probes must exhibit minimal nonspecific binding and be compact. As a result, QD-immunofluorescence has focused primarily on cell surface targets. By creating compact QD-F(ab')2, we sensitively detected alpha-tubulin with a ∼50-fold higher signal-to-noise ratio compared to organic dye-based labeling. PPFPA represents a versatile and accessible platform for tailoring QD surfaces, offering a pathway to realize the full potential of colloidal QDs in various scientific applications. Materials science ; Prepolymer ; Quantum dot ; Nanotechnology ; Surface modification ; Surface (topology) ; Chemical engineering ; Composite material ; Polyurethane Quantum Dots Synthesis And Properties ; Polymer Surface Interaction Studies ; Molecular Junctions and Nanostructures