jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Emma J. Jordan | Ethan Calder | Bethan L. Greene | Holly V. Adcock | Louise Male | Paul Davies | Andrew R. Jupp
Source: Organometallics (article, 2024-09-06)
Field: Chemistry — Inorganic Chemistry

Tuning the Electronic Properties of Azophosphines as Ligands and Their Application in Base-Free Transfer Hydrogenation Catalysis The design and tuning of new ligands is crucial for unlocking new reactivity at transition metal centers. Azophosphines have recently emerged as a new class of 1,3-P,N ligands in ruthenium piano-stool complexes. This work shows that the azophosphine synthesis can tolerate <i>N</i>-aryl substituents with strongly electron-donating and electron-withdrawing <i>para</i>-R groups and that the nature of this R group can affect the spectroscopic and structural properties of the azophosphines, as measured by NMR spectroscopy, UV-vis spectroscopy, single-crystal X-ray diffraction, and DFT studies. Azophosphines are shown to be relatively weak phosphine donors, as shown by analysis of the <sup>1</sup> <i>J</i> <sub>P-Se</sub> coupling constants of the corresponding azophosphine selenides, but the donor properties can be fine tuned within this area of chemical space. Monodentate and bidentate Ru-azophosphine complexes were prepared, and their first use as a catalyst was probed. The Ru-azophosphine complexes were found to promote the transfer hydrogenation of acetophenone to 1-phenylethanol without the requirement of a harsh base additive, and the bidentate complex was more active than the monodentate analogue. Chemistry ; Catalysis ; Base (topology) ; Transfer hydrogenation ; Free base ; Combinatorial chemistry ; Transfer (computing) ; Organic chemistry ; Polymer chemistry ; Ruthenium Asymmetric Hydrogenation and Catalysis ; Chemical Synthesis and Analysis ; Innovative Microfluidic and Catalytic Techniques Innovation
Authors: Svetlana Lukáš Petrova | Alessandro Jäger | Ewa Pavlova | Martina Vragović | Eliézer Jäger | Miloš Steinhart | Damir Klepac
Source: European Polymer Journal (article, 2024-09-23)
Field: Chemistry — Organic Chemistry

Probing the inner structure and dynamics of pH-sensitive block copolymer nanoparticles with nitroxide radicals using scattering and EPR techniques Electron paramagnetic resonance ; Copolymer ; Nitroxide mediated radical polymerization ; Radical ; Materials science ; Scattering ; Nanoparticle ; Dynamics (music) ; Photochemistry ; Polymer chemistry ; Polymer ; Chemical engineering ; Chemical physics ; Chemistry ; Nanotechnology ; Radical polymerization ; Nuclear magnetic resonance ; Optics ; Organic chemistry ; Physics ; Composite material Advanced Polymer Synthesis and Characterization ; Conducting polymers and applications ; Electron Spin Resonance Studies
Authors: Mattia Bartoli | Francesca Cardano | Erik Piatti | Stefania Lettieri | Andréa Fin | Alberto Tagliaferro
Source: Beilstein Journal of Nanotechnology (review, 2024-08-16)
Field: Materials Science — Materials Chemistry

Interface properties of nanostructured carbon-coated biological implants: an overview The interfaces between medical implants and living tissues are of great complexity because of the simultaneous occurrence of a wide variety of phenomena. The engineering of implant surfaces represents a crucial challenge in material science, but the further improvement of implant properties remains a critical task. It can be achieved through several processes. Among them, the production of specialized coatings based on carbon-based materials stands very promising. The use of carbon coatings allows one to simultaneously fine-tune tribological, mechanical, and chemical properties. Here, we review applications of nanostructured carbon coatings (nanodiamonds, carbon nanotubes, and graphene-related materials) for the improvement of the overall properties of medical implants. We are focusing on biological interactions, improved corrosion resistance, and overall mechanical properties, trying to provide a complete overview within the field. Materials science ; Graphene ; Nanotechnology ; Carbon fibers ; Carbon nanotube ; Tribology ; Corrosion ; Coating ; Composite material ; Composite number Diamond and Carbon-based Materials Research ; Lubricants and Their Additives ; Tribology and Wear Analysis
Authors: Михаил В. Вараксин | Олег Н. Чупахин | Igor A. Lavrinchenko | Egor A. Nikiforov | Timofey D. Moseev | Anton N. Tsmokalyuk | Thomas V. Nechaev | Valery N. Charushin
Source: Synthesis (article, 2024-02-22)
Field: Materials Science — Materials Chemistry

Synthesis, Photophysical, and AIE Properties of 2H-Imidazole-Derived Push-Pull Fluorophores Abstract A four-stage method for the synthesis of 2H-imidazole-derived push-pull fluorophores was developed. The synthesized compounds are characterized by absorption in the range of 250–400 nm, emission of up to 617 nm, and quantum yields of up to 99%. Compounds bearing a tetraphenylethylene fragment demonstrated the AIE effect in a solution with a water fraction fw &gt;90% and significant increase in the emission intensity of up to 20 times and quantum yields of up to 22%. The ICT states for these fluorophores were confirmed by calculating the excited state dipole moments (&gt;23D). The reported synthetic method enables fine-tuning of the fluorescent properties for the developed photoactive molecular systems by varying donor fragments. The obtained compounds could be of particular interest in the design of photoactive organic and hybrid materials. Chemistry ; Imidazole ; Push pull ; Photochemistry ; Aggregation-induced emission ; Combinatorial chemistry ; Fluorescence ; Organic chemistry ; Optics Luminescence and Fluorescent Materials ; Molecular Sensors and Ion Detection ; Supramolecular Chemistry and Complexes
Authors: Daniela Caschera | Benedetta Brugnoli | Ludovica Primitivo | Martina De Angelis | Giuliana Righi | L. Pilloni | Gaetano Campi | P. Imperatori | Marzia Pentimalli | Andrea Masi | Andrea Liscio | Giuseppina Rea | Lorenza Suber
Source: Inorganic Chemistry (article, 2024-02-15)
Field: Materials Science — Materials Chemistry

Synthesis of Photoluminescent 2D Self-Assembled Silver Thiolate Nanoclusters for Sensors and Biomolecule Support Silver thiolate nanoclusters (Ag NCs) show distinctive optical properties resulting from their hybrid nature, metallic and molecular, exhibiting size-, structure-, and surface-dependent photoluminescence, thus enabling the exploitation of Ag NCs for potential applications in nanobiotechnology, catalysis, and biomedicine. However, tailoring Ag NCs for specific applications requires achieving long-term stability and may involve modifying surface chemistry, fine-tuning ligand composition, or adding functional groups. In this study, we report the synthesis of novel Ag NCs using 2-ethanephenylthiolate (SR) as a ligand, highlight critical points addressing stability, and characterize their optical and structural properties. A preliminary electrical characterization revealed high anisotropy, well suited for potential use in electronics/sensing applications. We also present the synthesis and characterization of Ag NCs using 10-carboxylic 2-ol thiolate (SR'COOH) having a terminal carboxylic group for conjugation with amine-containing molecules. We present a preliminary assessment of its bioconjugation capability using bovine serum albumin as a model protein indicating its prospective application as a biomolecule support. Nanoclusters ; Chemistry ; Bioconjugation ; Biomolecule ; Photoluminescence ; Nanotechnology ; Ligand (biochemistry) ; Molecule ; Combinatorial chemistry ; Characterization (materials science) ; Nanobiotechnology ; Nanoparticle ; Organic chemistry ; Materials science Nanocluster Synthesis and Applications ; Gold and Silver Nanoparticles Synthesis and Applications ; Advanced Nanomaterials in Catalysis
Authors: Zhong‐Shuai Zhu | Pengtang Wang | Ya Liu | Shuang Zhong | Xiaoguang Duan | Shaobin Wang
Source: Environmental Functional Materials (article, 2024-06-01)
Field: Materials Science — Materials Chemistry

Microenvironment modulation of carbon-based single-atom catalysts for advanced oxidation processes Advanced oxidation processes (AOPs) are among the most effective technologies for environmental remediation, particularly in removing recalcitrant organic pollutants from water. Carbon-based single-atom catalysts (CSACs) combine the strengths of both heterogeneous and homogeneous catalysts and maximize metal utilization via isolated metal active sites, thus fine-tuning the catalytic efficiency in AOPs via engineering molecular architecture. Atomically dispersed metal atoms are usually stabilized through ionic or covalent interactions with neighboring atoms, thus the geometric and electronic properties of CSACs are significantly affected by their local microenvironment. In this review, we explored recent advances in CSAC synthesis, emphasizing both bottom-up and top-down strategies, with a focus on microenvironment modulation. We also discussed the local microenvironment regulation of CSACs in AOPs, considering factors such as the first coordination sphere (metal center choice, site spacing/density and coordination structure) and the medium to long-range coordination (bimetallic doping, heteroatom doping/defect engineering and interface coupling). Finally, we outlined the challenges and prospects of CSAC microenvironment engineering, providing insights for advancing CSACs development in AOPs and beyond. • Synthesis of carbon-based single atom catalysts (CSACs) were summarized. • Influences of CSACs microevironment on advanced oxidation processes were reviewed. • The first sphere and medium to long-range coordinations of CSACs were discussed. • Challenges and perspectives in fundamental and engineering of CSACs were proposed. Catalysis ; Modulation (music) ; Atom (system on chip) ; Carbon fibers ; Carbon atom ; Materials science ; Chemical engineering ; Chemistry ; Nanotechnology ; Computer science ; Physics ; Engineering ; Parallel computing ; Organic chemistry Catalytic Processes in Materials Science ; Electrocatalysts for Energy Conversion ; Catalysis and Oxidation Reactions
Authors: Watchareeya Kaveevivitchai | Teng‐Hao Chen
Source: ChemPhysChem (article, 2024-08-27)
Field: Chemistry — Inorganic Chemistry

Emerging Mixed‐Valence Porous Materials The development and applications of porous materials have been revolutionized over the past decades. To fine-tune their fascinating behaviors such as charge-transport, magnetic, and catalytic properties, one of the most effective strategies is incorporating mixed valency into the structures. This Concept provides recent progress on emerging crystalline porous materials, namely, metal-organic frameworks, metal-organic polyhedra, covalent organic frameworks, and hydrogen-bonded organic frameworks, where their mixed valency is either intrinsic or postsynthetically induced via an external stimulus. We further highlight the investigation of mixed valency and potential applications, which sheds light on the design and exploitation of mixed-valence crystalline porous materials. Valency ; Valence (chemistry) ; Porosity ; Metal-organic framework ; Materials science ; Porous medium ; Nanotechnology ; Chemistry ; Composite material ; Organic chemistry ; Adsorption Metal-Organic Frameworks: Synthesis and Applications ; Covalent Organic Framework Applications ; Nanomaterials for catalytic reactions
Authors: N. K. Patra | Astha Gupta | Prasad V. Bharatam
Source: Journal of Computational Chemistry (article, 2024-10-30)
Field: Chemistry — Organic Chemistry

Stable, aromatic, and electrophilic azepinium ions: Design using quantum chemical methods Cyclic nitrenium ions containing five-membered and six-membered rings are available, however, the seven-membered cyclic nitrenium ions (azepinium ions) are rare. The chemistry of these species is related to their stability originating from the aromaticity due to 6π electrons. Very few theoretical and experimental studies have been conducted on the azepinium ions. Related clozapine and olanzapine cations (diazepinium ions) were observed during drug metabolism studies. In this work, quantum chemical analysis has been carried out to estimate the stability, aromaticity, and electrophilicity of several derivatives of azepinium ions. A few of the designed azepinium ions carry ΔE<sub>S-T</sub> values in the range of 50 kcal/mol favoring singlet state; π donating groups at the 2nd position increase the singlet-triplet energy differences. Most of the substituents reduce the NICS(1) values compared to the parent system. Ring fusion with heterocyclic five-membered rings generally increases the aromaticity and the stability of the azepinium ion ring systems. The electrophilicity parameters estimated in terms of HIA, FIA, and ω values indicate that it is possible to fine-tune the chemical properties of azepinium ions with appropriate modulation. Aromaticity ; Chemistry ; Singlet state ; Electrophile ; Ion ; Ring (chemistry) ; Computational chemistry ; Chemical stability ; Photochemistry ; Organic chemistry ; Molecule ; Excited state ; Atomic physics Chemical Reaction Mechanisms ; Structural and Chemical Analysis of Organic and Inorganic Compounds ; Organic Chemistry Cycloaddition Reactions
Authors: Kennedy A. Guillot | Philip J. Brahana | Ahmed Al Harraq | Nduka D. Ogbonna | Nicholas S. Lombardo | Jimmy Lawrence | Yaxin An | Michael G. Benton | Bhuvnesh Bharti
Source: JACS Au (article, 2024-03-04)
Field: Materials Science — Materials Chemistry

Selective Vapor Condensation for the Synthesis and Assembly of Spherical Colloids with a Precise Rough Patch Patchy particles occupy an increasingly important space in soft matter research due to their ability to assemble into intricate phases and states. Being able to fine-tune the interactions among these particles is essential to understanding the principles governing the self-assembly processes. However, current fabrication techniques often yield patches that deviate chemically and physically from the native particles, impeding the identification of the driving forces behind self-assembly. To overcome this challenge, we propose a new approach to synthesizing spherical colloids with a well-defined rough patch on their surface. By treating polystyrene microspheres with vapors of a good solvent, here an acetone-water mixture, we achieve selective polymer corrugation on the particle surface resulting in a chemically similar yet rough surface patch. The key step is the selective condensation of the acetone-water vapors on the apex of the polystyrene microparticles immobilized on a substrate, which leads to rough patch formation. We leverage the ability to tune the vapor-liquid equilibrium of the volatile acetone-water mixture to precisely control the polymer corrugation on the particle surface. We demonstrate the dependence of patch formation on particle and substrate wettability, with the condensation occurring on the particle apex only when it is more wettable than the substrate, which is consistent with Volmer's classical nucleation theory. By combining experiments and molecular dynamics simulations, we identify the role of the rough patch in the depletion interaction-driven self-assembly of the microspheres, which is crucial for designing programmable supracolloidal structures. Polystyrene ; Condensation ; Materials science ; Wetting ; Particle (ecology) ; Nanotechnology ; Polymer ; Nucleation ; Chemical physics ; Colloid ; Chemical engineering ; Substrate (aquarium) ; Chemistry ; Composite material ; Organic chemistry Pickering emulsions and particle stabilization ; Proteins in Food Systems ; Surfactants and Colloidal Systems
Authors: Hong Jiang | Martin Milanov | Gabriela Jüngert | Larissa Angebauer | Clara Flender | Eva Smudde | Fabian Gather | Tanja Vogel | Henning J. Jessen | Hans‐Georg Koch
Source: iScience (article, 2024-06-13)
Field: Materials Science — Materials Chemistry

Control of a chemical chaperone by a universally conserved ATPase The universally conserved YchF/Ola1 ATPases regulate stress response pathways in prokaryotes and eukaryotes. Deletion of YchF/Ola1 leads to increased resistance against environmental stressors, such as reactive oxygen species, while their upregulation is associated with tumorigenesis in humans. The current study shows that in <i>E. coli</i>, the absence of YchF stimulates the synthesis of the alternative sigma factor RpoS by a transcription-independent mechanism. Elevated levels of RpoS then enhance the transcription of major stress-responsive genes. In addition, the deletion of <i>ychF</i> increases the levels of polyphosphate kinase, which in turn boosts the production of the evolutionary conserved and ancient chemical chaperone polyphosphate. This potentially provides a unifying concept for the increased stress resistance in bacteria and eukaryotes upon YchF/Ola1 deletion. Intriguingly, the simultaneous deletion of <i>ychF</i> and the polyphosphate-degrading enzyme exopolyphosphatase causes synthetic lethality in <i>E. coli</i>, demonstrating that polyphosphate production needs to be fine-tuned to prevent toxicity. rpoS ; Polyphosphate ; Sigma factor ; Biology ; Chaperone (clinical) ; Transcription factor ; ATPase ; Transcription (linguistics) ; Cell biology ; Gene ; Enzyme ; Biochemistry ; Genetics ; Gene expression ; Promoter Enzyme Structure and Function ; Bacterial Genetics and Biotechnology ; DNA Repair Mechanisms
Authors: Zhandos Tolepov | O. Prikhodko | Alexander V. Kolobov | G. A. Ismailova | Svetlana Mikhailova | Nazim Guseinov | Ye. S. Mukhametkarimov | Alimzhan Kapanov | S. Ya. Maksimova
Source: Journal of Non-Crystalline Solids (article, 2024-08-09)
Field: Materials Science — Materials Chemistry

Effect of Bi addition on the switching effect and structure of thin Ge2Sb2Te5 films prepared by ion-plasma RF co-sputtering Ge 2 Sb 2 Te 5 (GST) films are widely used in non-volatile phase-change memory devices, their properties can be fine-tuned by element doping. In this work, current-voltage (I-V) characteristics of the switching process and the structure of phase-change GST films doped with Bi concentration from 0 to 9.2 at.% have been studied, the parameters of the switching process were found dependent on Bi content. The composition with Bi 6.3 at.% was found to have optimal values of power consumption and switching time. XRD and XPS analyses show that amorphous and crystalline phases in this material, unlike other compositions, are formed by very similar structural blocks with Bi atoms making chemical bonds only with Te atoms. Sputtering ; Thin film ; Materials science ; Ion ; Plasma ; Optoelectronics ; Analytical Chemistry (journal) ; Nanotechnology ; Chemistry ; Physics ; Chromatography Phase-change materials and chalcogenides ; Optical and Acousto-Optic Technologies ; Chalcogenide Semiconductor Thin Films
Authors: Serap Başkır | Alican Onur Cankaya | Emre Tekay | Berkay Erenay | Bora Gari̇pcan | Özgür Kocatürk
Source: Polymer International (article, 2024-11-29)
Field: Materials Science — Polymers and Plastics

Shape memory polyurethane synthesis using glycerol as chain extender for biomedical applications Abstract Incorporation of shape memory polymers into biomedical devices is an attractive option due to their notable advantages of low cost, biocompatibility, tunable degradability, patient‐specific design and adjustable mechanical and thermal properties. Shape memory polyurethanes are particularly attractive due to their extensive temperature range for shape recovery as well as the ability to fine‐tune the glass transition temperature. This study aimed to synthesize a shape memory polyurethane using glycerol as chain extender with a glass transition temperature within a suitable temperature range for biomedical applications. The results showed that the triggering temperatures for the synthesized samples change between 63.95 °C and 88.21 °C. Shape memory properties were investigated for the temperature range 40–75 °C. Shape recovery times were found to be substantial with increasing temperature with ~102 s at 40 °C and ~1 s at 75 °C. Shape fixity and shape recovery rates for the same temperature ranges were 77.8% and 85.6% at 40 °C and 100% and 100% for 75 °C. The cytotoxicity assay indicates promising biocompatibility of the synthesized material for biomedical purposes. Overall, the synthesized polymers were found to be a potential candidate for biomedical applications such as stents, aneurysm filling or occlusion devices. © 2024 Society of Chemical Industry. Extender ; Polyurethane ; Materials science ; Shape-memory alloy ; Glycerol ; Chain (unit) ; Composite material ; Polymer science ; Chemical engineering ; Chemistry ; Engineering ; Organic chemistry ; Physics Polymer composites and self-healing ; Marine Sponges and Natural Products ; Photochromic and Fluorescence Chemistry
Authors: Adrià Roig | Jesús Padilla | Silvia De la Flor | Àngels Serra
Source: European Polymer Journal (article, 2024-12-31)
Field: Materials Science — Biomaterials

Biobased poly(amido-imide) CANs catalyzed by lanthanide triflates: High creep resistance and superior reprocessability Imide ; Lanthanide ; Creep ; Catalysis ; Materials science ; Polymer chemistry ; Composite material ; Organic chemistry ; Chemistry ; Ion biodegradable polymer synthesis and properties ; Carbon dioxide utilization in catalysis ; Synthetic Organic Chemistry Methods
Authors: Аlexey N. Bilyachenko | Victor N. Khrustalev | Zhibin Huang | Kristina D. Dubinina | Elena S. Shubina | Н. Н. Лобанов | Di Sun | Elisabete C. B. A. Alegria | Armando J. L. Pombeiro
Source: Nanoscale (article, 2024-01-01)
Field: Chemistry — Organic Chemistry

An ionic Cu<sub>9</sub>Na<sub>4</sub>-phenylsilsesquioxane/bis(triphenylphosphine)iminium complex: synthesis, unique structure, and catalytic activity The synthesis of a high nuclear (Cu<sub>9</sub>Na<sub>4</sub>) complex 1<i>via</i> the self-assembly of copper(II) phenylsilsesquioxane induced by complexation with bis(triphenylphosphine)iminium chloride (PPNCl) was successfully achieved. This complex, which includes two bis(triphenylphosphine)iminium PPN<sup>+</sup> cations, represents the first example of a metallasilsesquioxane/phosphazene compound. The Cu<sub>9</sub>Na<sub>4</sub>-silsesquioxane cage demonstrates a nontrivial combination of two pairs of Si<sub>6</sub>-cyclic/Si<sub>4</sub>-acyclic silsesquioxane ligands and a fusion of two Si<sub>10</sub>Cu<sub>4</sub>Na<sub>2</sub> fragments, combined <i>via</i> the central ninth copper ion. The catalytic efficacy of the copper(II) compound (1) was evaluated through the peroxidative oxidation of toluene using <i>tert</i>-butyl hydroperoxide (<i>t</i>-BuOOH) as the oxidant. The primary oxidation products were benzaldehyde (BAL), benzyl alcohol (BOL), and benzoic acid (BAC), with BAC being the predominant product, especially in acetonitrile (NCMe). The formation of cresols, indicating oxidation at the aromatic ring, was observed only in water and under microwave irradiation (MW) in NCMe. Remarkably, the highest total yield of 40.3% was achieved in water with an acidic additive at 80 °C, highlighting the crucial role of the acid additive in enhancing reaction efficiency and selectivity. This study underscores our copper(II) complex as a highly effective catalyst for toluene oxidation, demonstrating its significant potential for fine-tuning reaction parameters to optimize yields and selectivity. The unprecedented structure of the complex and its promising catalytic performance pave the way for further advancements in the fields of metallasilsesquioxane chemistry and catalysis. Triphenylphosphine ; Iminium ; Catalysis ; Phosphazene ; Toluene ; Dopant ; Ionic bonding ; Chemistry ; Inorganic chemistry ; Materials science ; Ion ; Doping ; Organic chemistry ; Polymer Organometallic Complex Synthesis and Catalysis ; Catalytic Processes in Materials Science ; Silicone and Siloxane Chemistry