jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Caroline Ndung’U | Petia Bobadova‐Parvanova | Daniel J. LaMaster | Dylan Goliber | Frank R. Fronczek | M. Graça H. Vicente
Source: Molecules (article, 2023-06-06)
Field: Materials Science — Materials Chemistry

8(meso)-Pyridyl-BODIPYs: Effects of 2,6-Substitution with Electron-Withdrawing Nitro, Chloro, and Methoxycarbonyl Groups The introduction of electron-withdrawing groups on 8(<i>meso</i>)-pyridyl-BODIPYs tends to increase the fluorescence quantum yields of this type of compound due to the decrease in electronic charge density on the BODIPY core. A new series of 8(<i>meso</i>)-pyridyl-BODIPYs bearing a 2-, 3-, or 4-pyridyl group was synthesized and functionalized with nitro and chlorine groups at the 2,6-positions. The 2,6-methoxycarbonyl-8-pyridyl-BODIPYs analogs were also synthesized by condensation of 2,4-dimethyl-3-methoxycarbonyl-pyrrole with 2-, 3-, or 4-formylpyridine followed by oxidation and boron complexation. The structures and spectroscopic properties of the new series of 8(<i>meso</i>)-pyridyl-BODIPYs were investigated both experimentally and computationally. The BODIPYs bearing 2,6-methoxycarbonyl groups showed enhanced relative fluorescence quantum yields in polar organic solvents due to their electron-withdrawing effect. However, the introduction of a single nitro group significantly quenched the fluorescence of the BODIPYs and caused hypsochromic shifts in the absorption and emission bands. The introduction of a chloro substituent partially restored the fluorescence of the mono-nitro-BODIPYs and induced significant bathochromic shifts. Bathochromic shift ; Chemistry ; Hypsochromic shift ; Polar effect ; Fluorescence ; Substituent ; Nitro ; Photochemistry ; Pyrrole ; Acetic anhydride ; Medicinal chemistry ; Organic chemistry ; Catalysis Luminescence and Fluorescent Materials ; Organic Light-Emitting Diodes Research ; Molecular Sensors and Ion Detection
Authors: Paulina Chytrosz-Wróbel | Monika Gołda‐Cępa | Kamil Drożdż | Jakub Rysz | Piotr Kubisiak | Waldemar Kulig | Monika Brzychczy‐Włoch | Lukasz Cwiklik | Andrzej Kotarba
Source: ACS Biomaterials Science & Engineering (article, 2023-11-01)
Field: Materials Science — Polymers and Plastics

In Vitro and In Silico Studies of Functionalized Polyurethane Surfaces toward Understanding Biologically Relevant Interactions The solid-aqueous boundary formed upon biomaterial implantation provides a playground for most biochemical reactions and physiological processes involved in implant-host interactions. Therefore, for biomaterial development, optimization, and application, it is essential to understand the biomaterial-water interface in depth. In this study, oxygen plasma-functionalized polyurethane surfaces that can be successfully utilized in contact with the tissue of the respiratory system were prepared and investigated. Through experiments, the influence of plasma treatment on the physicochemical properties of polyurethane was investigated by atomic force microscopy, attenuated total reflection infrared spectroscopy, differential thermal analysis, X-ray photoelectron spectroscopy, secondary ion mass spectrometry, and contact angle measurements, supplemented with biological tests using the A549 cell line and two bacteria strains (<i>Staphylococcus aureus</i> and <i>Pseudomonas aeruginosa</i>). The molecular interpretation of the experimental findings was achieved by molecular dynamics simulations employing newly developed, fully atomistic models of unmodified and plasma-functionalized polyurethane materials to characterize the polyurethane-water interfaces at the nanoscale in detail. The experimentally obtained polar and dispersive surface free energies were consistent with the calculated free energies, verifying the adequacy of the developed models. A 20% substitution of the polymeric chain termini by their oxidized variants was observed in the experimentally obtained plasma-modified polyurethane surface, indicating the surface saturation with oxygen-containing functional groups. In silico ; Polyurethane ; In vitro ; Materials science ; Nanotechnology ; Chemistry ; Composite material ; Biochemistry Polymer composites and self-healing ; Advanced Sensor and Energy Harvesting Materials ; Cephalopods and Marine Biology
Authors: Aykut Baki | Mohamed Abdeldayem | Carlos Morales | Jan Ingo Flege | Detlef Klimm | Oliver Bierwagen | Jutta Schwarzkopf
Source: Crystal Growth & Design (article, 2023-03-16)
Field: Materials Science — Materials Chemistry

Potential of La-Doped SrTiO<sub>3</sub> Thin Films Grown by Metal–Organic Vapor Phase Epitaxy for Thermoelectric Applications La-doped SrTiO<sub>3</sub> thin films with high structural quality were homoepitaxially grown by the metal-organic vapor phase epitaxy (MOVPE) technique. Thermogravimetric characterization of the metal-organic precursors determines suitable flash evaporator temperatures for transferring the liquid source materials in the gas phase of the reactor chamber. An adjustment of the charge carrier concentration in the films, which is necessary for optimizing the thermoelectric power factor, was performed by introducing a defined amount of the metal-organic compound La(tmhd)<sub>3</sub> and tetraglyme to the liquid precursor solution. X-ray diffraction and atomic force microscopy verified the occurrence of the pure perovskite phase exhibiting a high structural quality for all La concentrations. The electrical conductivity of the films obtained from Hall-effect measurements increases linearly with the La concentration in the gas phase, which is attributed to the incorporation of La<sup>3+</sup> ions on the Sr<sup>2+</sup> perovskite sites by substitution inferred from photoemission spectroscopy. The resulting structural defects were discussed concerning the formation of occasional Ruddlesden-Popper-like defects. The thermoelectric properties determined by Seebeck measurements demonstrate the high potential of SrTiO<sub>3</sub> thin films grown by MOVPE for thermoelectric applications. Thermoelectric effect ; Metalorganic vapour phase epitaxy ; Materials science ; Seebeck coefficient ; Thin film ; Perovskite (structure) ; Epitaxy ; Doping ; Analytical Chemistry (journal) ; Phase (matter) ; Thermoelectric materials ; Nanotechnology ; Optoelectronics ; Chemistry ; Crystallography ; Thermal conductivity ; Organic chemistry ; Composite material Electronic and Structural Properties of Oxides ; Advanced Thermoelectric Materials and Devices ; Magnetic and transport properties of perovskites and related materials
Authors: Marco Serra | Nikolas Antonatos | Jan Luxa | Luc Lajaunie | Josep Albero | Agata Sabik | W. M. Linhart | Hermenegildo Garcı́a | R. Kudrawiec | David Sedmidubský | Zdeněk Sofer
Source: Journal of Materials Chemistry C (article, 2023-01-01)
Field: Materials Science — Materials Chemistry

A high-performance “fueled” photodetector based on few-layered 2D ternary chalcogenide NiGa<sub>2</sub>S<sub>4</sub> The activity of “fueled” NiGa 2 S 4 /ITO photodetector is described. The presence of ethanol boosts the performances of the photodetector increasing its responsivity and spectral response. Photodetector ; Materials science ; Responsivity ; Chalcogenide ; Ternary operation ; Optoelectronics ; Computer science 2D Materials and Applications ; Perovskite Materials and Applications ; Chalcogenide Semiconductor Thin Films
Authors: A. S. Naumov | G. Yu. Shakhgil’dyan | N. V. Golubev | A. S. Lipatiev | С. С. Федотов | R. O. Alekseev | Elena S. Ingat’eva | Vitaliy I. Savinkov | В. Н. Сигаев
Source: Ceramics (article, 2023-12-22)
Field: Materials Science — Ceramics and Composites

Tuning the Coefficient of Thermal Expansion of Transparent Lithium Aluminosilicate Glass-Ceramics by a Two-Stage Heat Treatment Transparent glass-ceramics with a Li2O–Al2O3–SiO2 (LAS) system have been extensively utilized in optical systems in which thermal stability is of utmost importance. This study is aimed to develop thermal treatment routes that can effectively control the structure of transparent LAS glass-ceramics and tune its thermal expansion coefficient within a wide range for novel applications in photonics and integrated optics. The optimal conditions for the nucleation and crystallization of LAS glass were determined by means of differential scanning calorimetry and a polythermal analysis. XRD, Raman spectroscopy, and TEM microscopy were employed to examine the structural changes which occurred after heat treatments. It was found that the second stage of heat treatment promotes the formation of β-eucryptite-like solid solution nanocrystals, which enables effective control of the coefficient of thermal expansion of glass-ceramics in a wide temperature range of −120 to 500 °C. This work provides novel insights into structural rearrangement scenarios occurring in LAS glass, which are crucial for accurately predicting its crystallization behavior and ultimately achieving transparent glass-ceramics with desirable properties. Materials science ; Aluminosilicate ; Crystallization ; Thermal expansion ; Ceramic ; Differential scanning calorimetry ; Nucleation ; Glass-ceramic ; Raman spectroscopy ; Lithium (medication) ; Mineralogy ; Glass transition ; Atmospheric temperature range ; Composite material ; Chemical engineering ; Optics ; Thermodynamics ; Chemistry ; Polymer Glass properties and applications ; Luminescence Properties of Advanced Materials ; Ferroelectric and Piezoelectric Materials
Authors: Benjamin A. Legg | James J. De Yoreo
Source: Langmuir (article, 2023-02-14)
Field: Materials Science — Materials Chemistry

Effects of Size and Shape on the Tolerances for Misalignment and Probabilities for Successful Oriented Attachment of Nanoparticles Oriented attachment (OA) of nanoparticles is an important pathway of crystal growth, but there is a lack of tools to model OA. Here, we present several simple models that relate the probability of achieving OA to basic geometric parameters, such as particle size, shape, and lattice periodicity. A Moiré-domain model is applied to understand twist misorientations between parallel surfaces, and it predicts that the range of twist angles yielding perfect OA is inversely related to the width of the contact area. This idea is explored further through a surface functional model, which investigates how patterns of crystallographic registration can drive the emergence of complex orientational energy landscapes. The energy landscapes are predicted to possess multiple local minima that can trap particles in imperfect alignments, and these local minima become deeper and more numerous as the contact area increases, which makes OA more challenging for large particles. A second set of models is presented to understand the sequence of events by which two crystallographic faces become coplanar after the collision. We use a central force approximation to predict the odds that two particle faces will attain coalignment when the particles collide with random misalignments, and we show that in the absence of special biasing forces, the probability of attaining alignment on a given face is roughly proportional to its solid angle as viewed from the center of the particle. The model thus predicts that OA is most favorable between well-faceted particles and becomes exceedingly unlikely for large spherical particles that express many microfacets. Maxima and minima ; Statistical physics ; Nanoparticle ; Range (aeronautics) ; Particle (ecology) ; Energy landscape ; Collision ; Physics ; Surface (topology) ; Materials science ; Nanotechnology ; Geometry ; Computer science ; Mathematics ; Mathematical analysis ; Geology Quantum Dots Synthesis And Properties ; nanoparticles nucleation surface interactions ; Polymer Surface Interaction Studies
Authors: César Rodríguez | Sonia Moreno | Rafael Molina
Source: MethodsX (article, 2023-01-01)
Field: Materials Science — Materials Chemistry

Operando DRIFT-MS for studying the oxidative steam reforming of ethanol (OSRE) reaction An operando DRIFT-MS system (Diffuse Reflectance Infrared Fourier Transform Spectroscopy coupled with Mass Spectrometry) was designed and set up to study the oxidative steam reforming of ethanol reaction (OSRE). This reaction involves the mixture of water, ethanol and oxygen to produce mainly hydrogen, which is a rather attractive energy carrier. Spectroscopic monitoring of the process is a key tool to contribute to the understanding of: i) the dynamics on the catalyst surface, ii) the reaction mechanism and iii) the effect of the solid's properties on the catalytic process. In this sense, this document sets forth the experimental design that allows to carry out the study under operando DRIFT-MS conditions through time for the OSRE reaction. Selection criteria for parameters, materials, configuration, and experimental conditions are included, particularly optimizing the parameters of particle size and the dilution factor with KBr as well as the temperature and flow conditions for carrying out the reaction.•Clear signals of the adsorbed species in IR that do not present interference by water in the reaction atmosphere.•Simple assembly and online product detection by MS that allow to follow the change in the products of the OSRE reaction according to the temperature.•Controlled entry of gases and quantification by loop injection. Ethanol ; Oxidative phosphorylation ; Chemistry ; Steam reforming ; Steam explosion ; Waste management ; Pulp and paper industry ; Chemical engineering ; Organic chemistry ; Biochemistry ; Engineering ; Catalysis Catalytic Processes in Materials Science ; Catalysis and Oxidation Reactions ; Catalysts for Methane Reforming
Authors: Marina García-Carrión | Julio Ramírez‐Castellanos | Emilio Nogales | Bianchi Méndez
Source: Nanomaterials (article, 2023-04-23)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Temperature-Dependent and Time-Resolved Luminescence Characterization of γ-Ga2O3 Nanoparticles The temperature-dependent luminescence properties of γ-Ga<sub>2</sub>O<sub>3</sub> nanoparticles prepared by a precipitation method are investigated under steady-state and pulsed-light excitation. The main photoluminescence (PL) emission at room temperature consists of a single blue band centered around 2.76 eV, which hardly undergoes a blueshift of 0.03 eV when temperature goes down to 4 K. The emission behaves with a positive thermal quenching following an Arrhenius-type curve. The data fitting yields two non-radiative levels affecting the emission band with activation energies of 7 meV and 40 meV. On the other hand, time-resolved PL measurements have also been taken and studied as a function of the temperature. The data analysis has resulted in two lifetimes: one of 3.4 ns and the other of 32 ns at room temperature, which undergo an increase up to 4.5 ns and 65 ns at T = 4 K, respectively. Based on both stationary and dynamic PL results, a model of radiative and non-radiative levels associated with the main emission bands of γ-Ga<sub>2</sub>O<sub>3</sub> is suggested. Finally, by using PL excitation measurements, an estimation of the bandgap and its variation with temperature between 4 K and room temperature were obtained and assessed against O'Donnell-Chen's law. With this variation it has been possible to calculate the average of the phonon energy, resulting in ⟨<i>ħ</i>ω⟩ = 10 ± 1 meV. Photoluminescence ; Luminescence ; Materials science ; Arrhenius equation ; Radiative transfer ; Band gap ; Blueshift ; Quenching (fluorescence) ; Activation energy ; Analytical Chemistry (journal) ; Excitation ; Atomic physics ; Optoelectronics ; Chemistry ; Optics ; Physics ; Physical chemistry ; Fluorescence Ga2O3 and related materials ; ZnO doping and properties ; Advanced Photocatalysis Techniques
Authors: Fangyuan Liu | Xingxu Lu | Chunxiang Zhu | Zichao Bian | Xiaohui Song | Jiyu Sun | Bo Zhang | J. Weng | Ashwanth Subramanian | Xiao Tong | Lichun Zhang | Avinash M. Dongare | Chang‐Yong Nam | Yong Ding | Guoan Zheng | Haiyan Tan | Pu‐Xian Gao
Source: ACS Nano (article, 2023-06-23)
Field: Materials Science — Materials Chemistry

Unraveling Anisotropic and Pulsating Etching of ZnO Nanorods in Hydrochloric Acid via Correlative Electron Microscopy Despite much technical progress achieved so far, the exact surface and shape evolution during wet chemical etching is less unraveled, especially in ionically bonded ceramics. Herein, by using <i>in situ</i> liquid cell transmission electron microscopy, a repeated two-stage anisotropic and pulsating periodic etching dynamic is discovered during the pencil shape evolution of a single crystal ZnO nanorod in aqueous hydrochloric acid. Specifically, the nanopencil tip shrinks at a slower rate along [0001̅] than that along the ⟨101̅0⟩ directions, resulting in a sharper ZnO pencil tip. Afterward, rapid tip dissolution happens due to accelerated etching rates along various crystal directions. Concurrently, the vicinal base region of the original nanopencil tip emerges as a new tip followed by the repeated sequence of tip shrinking and removal. The high-index surfaces, such as {101̅<i>m</i>} (<i>m</i> = 0, 1, 2, or 3) and {21̅ 1̅<i>n</i>} (<i>n</i> = 0, 1, 2, or 3), are found to preferentially expose in different ratios. Our 3D electron tomography, convergent beam electron diffraction, middle-angle bright-field STEM, and XPS results indicate the dissociative Cl<sup>-</sup> species were bound to the Zn-terminated tip surfaces. Furthermore, DFT calculation suggests the preferential Cl<sup>-</sup> passivation over the {101̅1} and (0001) surfaces of lower energy than others, leading to preferential surface exposures and the oscillatory variation of different facet etching rates. The boosted reactivity due to high-index nanoscale surface exposures is confirmed by comparatively enhanced chemical sensing and CO<sub>2</sub> hydrogenation activity. These findings provide an in-depth understanding of anisotropic wet chemical etching of ionic nanocrystals and offer a design strategy for advanced functional materials. Nanorod ; Etching (microfabrication) ; Correlative ; Materials science ; Electron microscope ; Hydrochloric acid ; Nanotechnology ; Anisotropy ; Scanning electron microscope ; Microscopy ; Chemical engineering ; Optics ; Composite material ; Physics ; Metallurgy ZnO doping and properties ; Copper-based nanomaterials and applications ; Quantum Dots Synthesis And Properties
Authors: Nicole Müller | R. Banu | Adea Loxha | Florian Schrenk | Lorenz Lindenthal | Christoph Rameshan | Ernst Pittenauer | Jordi Llorca | Janis Timoshenko | Carlo Marini | Noelia Barrabés
Source: Communications Chemistry (article, 2023-12-18)
Field: Materials Science — Materials Chemistry

Dynamic behaviour of platinum and copper dopants in gold nanoclusters supported on ceria catalysts Understanding the behaviour of active catalyst sites at the atomic level is crucial for optimizing catalytic performance. Here, the evolution of Pt and Cu dopants in Au<sub>25</sub> clusters on CeO<sub>2</sub> supports is investigated in the water-gas shift (WGS) reaction, using operando XAFS and DRIFTS. Different behaviour is observed for the Cu and Pt dopants during the pretreatment and reaction. The Cu migrates and builds clusters on the support, whereas the Pt creates single-atom active sites on the surface of the cluster, leading to better performance. Doping with both metals induces strong interactions and pretreatment and reaction conditions lead to the growth of the Au clusters, thereby affecting their catalytic behaviour. This highlights importance of understanding the behaviour of atoms at different stages of catalyst evolution. These insights into the atomic dynamics at the different stages are crucial for the precise optimisation of catalysts, which ultimately enables improved catalytic performance. Nanoclusters ; Catalysis ; Dopant ; Materials science ; Cluster (spacecraft) ; Platinum ; Copper ; Atom (system on chip) ; Chemical engineering ; Chemical physics ; Water-gas shift reaction ; Nanotechnology ; Doping ; Inorganic chemistry ; Chemistry ; Metallurgy ; Organic chemistry Nanocluster Synthesis and Applications ; Catalytic Processes in Materials Science ; Advanced Nanomaterials in Catalysis
Authors: Monica Fiorenza Boselli | Niccolò Intini | Alessandra Puglisi | Laura Raimondi | Sergio Rossi | Maurizio Benaglia
Source: European Journal of Organic Chemistry (article, 2023-01-20)
Field: Chemistry — Organic Chemistry

Enantioselective Catalytic Addition of N‐Acyl Radicals: In Batch and In Flow Organophotoredox α‐Amination of Aldehydes Abstract The organophotoredox catalytic enantioselective addition of N ‐acyl radicals to aldehydes, to afford enantioenriched N ‐acyl 1,2 aminoalcohols was studied. Under the best conditions, in batch, the product was isolated in up to 52 % yield and 85 % e.e ., using a low cost and commercially available chiral imidazolidinone as organocatalyst. The reaction was then studied in flow, exploring different experimental setups and photoreactors. Although modest yields were obtained, the in‐flow process afforded the product in higher productivities (up to 60 times higher) and improved space time yields (increased up to 113 times) compared to the batch reaction, with no loss of stereoselectivity. Chemistry ; Enantioselective synthesis ; Yield (engineering) ; Amination ; Radical ; Catalysis ; Stereoselectivity ; Flow chemistry ; Organic chemistry ; Acylation ; Combinatorial chemistry Radical Photochemical Reactions ; Innovative Microfluidic and Catalytic Techniques Innovation ; Oxidative Organic Chemistry Reactions
Authors: Margaux Bossuat | Pauline Rullière | Nadège Preuilh | António Peixoto | Etienne Joly | Jean-Guillaume Gomez | Maroua Bourkhis | Frédéric Rodriguez | Fernanda Aguiar Gonçalves | Isabelle Fabing | Hafida Gaspard | Vania Bernardes‐Génisson | Valérie Maraval | Stéphanie Ballereau | Rémi Chauvin | Sébastien Britton | Yves Génisson
Source: Journal of Medicinal Chemistry (article, 2023-10-10)
Field: Chemistry — Organic Chemistry

Phenyl dialkynylcarbinols, a Bioinspired Series of Synthetic Antitumor Acetylenic Lipids A series of 25 chiral anti-cancer lipidic alkynylcarbinols (LACs) were devised by introducing an (hetero)aromatic ring between the aliphatic chain and the dialkynylcarbinol warhead. The resulting phenyl-dialkynylcarbinols (PACs) exhibit enhanced stability, while retaining cytotoxicity against HCT116 and U2OS cell lines with IC<sub>50</sub> down to 40 nM for resolved eutomers. A clickable probe was used to confirm the PAC prodrug behavior: upon enantiospecific bio-oxidation of the carbinol by the HSD17B11 short-chain dehydrogenase/reductase (SDR), the resulting ynones covalently modify cellular proteins, leading to endoplasmic reticulum stress, ubiquitin-proteasome system inhibition, and apoptosis. Insights into the design of LAC prodrugs specifically bioactivated by HSD17B11 vs its paralogue HSD17B13 were obtained. The HSD17B11/HSD17B13-dependent cytotoxicity of PACs was exploited to develop a cellular assay to identify specific inhibitors of these enzymes. A docking study was performed with the HSD17B11 AlphaFold model, providing a molecular basis of the SDR substrates mimicry by PACs. The safety profile of a representative PAC was established in mice. Chemistry ; Cytotoxicity ; Prodrug ; Endoplasmic reticulum ; Biochemistry ; Docking (animal) ; Enzyme ; Proteasome ; Stereochemistry ; Combinatorial chemistry ; In vitro Cyclization and Aryne Chemistry ; Synthesis of Indole Derivatives ; Synthesis and Characterization of Pyrroles