jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Masanori Wakizaka | Shraddha Gupta | Qingyun Wan | Shinya Takaishi | H. Noro | Kazunobu Sato | Masahiro Yamashita
Source: Research Square (preprint, 2023-08-02)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Tuning the spin qubit property of diamagnetic Zn(II) metal– organic frameworks via Cu(II) doping Abstract With the aim of developing a general method for the synthesis of molecular spin qubits, this work demonstrates a spin-center doping method based on the use of a metal–organic framework (MOF). As the MOF host, perovskite-type [CH 6 N 3 ][Zn II (HCOO) 3 ] doped with 5%, 2%, and 1% mol of Cu(II) ions is used. An analysis including X-ray fluorescence spectroscopy, magnetism, and the complete active space self-consistent field calculation method confirm the presence of dopant Cu(II) sites with the S = 1/2 system. Magnetic dynamics indicate the occurrence of a slow magnetic relaxation via the Raman process under an applied field, with a relaxation time of 3.5 ms (5% Cu), 9.2 ms (2% Cu), and 15 ms (1% Cu) at 1.8 K. Furthermore, pulse electron spin resonance spectroscopy reveals spin qubit properties with a Hahn echo decay time of 0.24 µs (2% Cu) and 0.41 µs (1% Cu) at 4 K as well as Rabi oscillation between M S = ± 1/2 spin sublevels. These relaxation-extending effects stem from the weakening of the spin–spin interactions between the Cu(II) sites and can be tuned by adjusting the dopant concentration. This work demonstrates a new application of MOFs as quantum materials having fine-tuning ability for spin qubits. Diamagnetism ; Qubit ; Spin (aerodynamics) ; Dopant ; Chemistry ; Relaxation (psychology) ; Electron paramagnetic resonance ; Doping ; Raman spectroscopy ; Condensed matter physics ; Analytical Chemistry (journal) ; Materials science ; Magnetic field ; Nuclear magnetic resonance ; Quantum ; Physics ; Quantum mechanics Magnetism in coordination complexes ; Lanthanide and Transition Metal Complexes ; Advanced NMR Techniques and Applications
Authors: Ephriem Mengesha | Yordanos T. Nibret | Abi Tadesse | Endale Teju | Tigabu Bekele | Zewdu Bezu
Source: SSRN Electronic Journal (article, 2023-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Size Dependent Solvatochromism of CDS Nanoparticles: Experimental Absorption and Fluorescence Analyses Solvatochromism ; Fluorescence ; Nanoparticle ; Absorption (acoustics) ; Photochemistry ; Materials science ; Nanotechnology ; Chemistry ; Optics ; Physics ; Composite material Gold and Silver Nanoparticles Synthesis and Applications ; Quantum Dots Synthesis And Properties ; Photochemistry and Electron Transfer Studies
Authors: Luke H Denoyer | Angelica Benavidez | A. J. Brearley | Kannan Ramaiyan | Fernando H. Garzón
Source: ECS Meeting Abstracts (article, 2023-08-28)
Field: Materials Science — Materials Chemistry

Chemical Stability of BaMg<sub>0.33</sub>Nb<sub>0.67-X</sub>Fe<sub>x</sub>O<sub>3-δ</sub> in High Temperature Methane Conversion Environments Doped perovskite metal oxide catalysts of the form AB x C 1-x O 3-δ are of interest to the catalysis community due to the ability to fine tune the catalytic activity or chemical stability through doping. Doped barium niobate perovskites have shown remarkable stability in CO 2 sensing and methane conversion measurements. However, the reason for the chemical stability is not well understood. Doping with transition metal cations for B site cations can lead to exsolution under reducing conditions. Many perovskites used for the oxidative coupling of methane (OCM) or the electrochemical oxidative coupling of methane (E-OCM) either lack long term stability, or catalytic activity within these highly reducing methane environments. Here, we present our results obtained with a highly stable Mg and Fe co-doped barium niobate perovskite BaMg 0.33 Nb 0.67-x Fe x O 3-δ (BMNF) that has shown activity in E-OCM setups over long term (&gt;100 hour) experiments and stability in CO 2 environments as a sensor.[1] The crystalline structure and atomic distributions within these synthesized materials analyzed via X-ray powder diffraction (XRD), scanning transmission microscopy (STEM), and X-ray photoelectron spectroscopy (XPS). Along with this, temperature programmed reaction (TPR) under 95% methane and 5% oxygen showed the effectiveness of the catalyst in an OCM setup, as well as the stability of the BMNF perovskite in methane. Through these analyses we posit that iron doping may increase the ionic conductivity of the BMNF material while change in Nb4+/5+ oxidation states prove stability in reducing environments.[2] (1) Denoyer, L. H.; Benavidez, A.; Garzon, F. H.; Ramaiyan, K. P. Highly Stable Doped Barium Niobate Based Electrocatalysts for Effective Electrochemical Coupling of Methane to Ethylene. Adv. Mater. Interfaces 2022 , 9 (27), 2200796. https://doi.org/10.1002/admi.202200796. (2) Denoyer, L. H.; Benavidez, A.; Garzon, F. H.; Ramaiyan, K. P. Chemical Stability of BaMg0.33Nb0.67-XFexO3-δ in High Temperature Methane Conversion Environments. under communication - ECS Journal of Solid State Science and Technology . Perovskite (structure) ; X-ray photoelectron spectroscopy ; Catalysis ; Methane ; Materials science ; Oxidative coupling of methane ; Anaerobic oxidation of methane ; Inorganic chemistry ; Barium ; Oxide ; Doping ; Transition metal ; Chemical stability ; Analytical Chemistry (journal) ; Chemical engineering ; Chemistry ; Crystallography Advancements in Solid Oxide Fuel Cells ; Catalysis and Oxidation Reactions ; Catalytic Processes in Materials Science
Authors: Ainara Valverde | Gabriel I. Tovar Jiménez | Natalia Ahiova Río-López | Dimas Ignacio Torres | Maibelín Rosales | Stefan Wuttke | Arkaitz Fidalgo-Marijuán | José Porro | Mónica Jiménez‐Ruiz | Victoria García Sakai | García. Andreina | José Manuel Laza | José Luis Vilas‐Vilela | Luís Lezama | M.I. Arriortua | Guillermo Javier Copello | Fernández de Luis
Source: Figshare (article, 2023-01-09)
Field: Chemistry — Inorganic Chemistry

Designing Metal-Chelator-like Traps by Encoding Amino Acids in Zirconium-Based Metal–Organic Frameworks Metal chelators and porous sorbents are two of the forefront technologies applied for the recovery and separation of hazardous and/or valuable metal ions from aqueous solutions. (<em>i.e.</em> polluted water sources, metal-rich mining wastewaters, acid leachates…). The transfer of the metal coordination functions of metal-chelators to chemically stable host materials had so far only limited success. Here, we report the installation of natural acids (<em>i.e.</em> malic acid, mercaptosuccinic acid, succinic acid, fumaric acid and citric acid) and amino acids (<em>i.e.</em> histidine, cysteine and asparagine) within a porous zirconium-based trimesate metal-organic framework (MOF), namely MOF-808. Applying this strategy, we were able to produce a pore environment spatially decorated with multiple functional groups usually found in commercial chelator molecules. The chemical stability of the amino acid molecules installed by solvent assisted ligand exchange has been studied to delimitate the applicability window of these materials. The adsorption affinity of MOF-808@(amino)acids in static and column-bed configurations can be fine-tuned as a function of the amino acid residues installed in the framework. MOF-808(Amino)acid columns can be applied efficiently both for water remediation of heavy metals, and for the separation of metal-ions with different acidities. For instance, the initial trends for the dispersion of rare earth elements have been identified. EPR and Inelastic Neutron Scattering spectroscopy reveals that MOF-808@(amino)acids stabilize metal centers as isolated and clustered species, in a coordination fashion that involves both the amine and thiol functions, and that affects the vibrational freedom of some of the chemical groups of the amino acid molecules. The metal-ions stabilization within an amino acid decorated MOFs opens the avenue to the application for pseudo bio-catalysis purposes in the near future. Zirconium ; Chelation ; Metal ; Metal-organic framework ; Materials science ; Chemistry ; Inorganic chemistry ; Metallurgy ; Organic chemistry Metal-Organic Frameworks: Synthesis and Applications ; Crystallization and Solubility Studies ; Polyoxometalates: Synthesis and Applications
Authors: Nowicki Waldemar
Source: SSRN Electronic Journal (preprint, 2023-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Systematic Studies of the Magnetocaloric Properties for the La0.65ca0.25x0.1mno3 Series (X = Alkali Metal and Alkaline Earth Metals) Alkaline earth metal ; Alkali metal ; Series (stratigraphy) ; Materials science ; Metal ; Geology ; Metallurgy ; Chemistry Magnetic and transport properties of perovskites and related materials ; Thermal Expansion and Ionic Conductivity ; Inorganic Chemistry and Materials
Authors: Juliana M. P. Almeida | Lucas H. Staffa | Débora Terezia Balogh | Antônio J. F. Carvalho
Source: Polymer International (article, 2023-09-08)
Field: Materials Science — Materials Chemistry

Fine‐tuning in‐plane interdomain spacing of polystyrene‐<i>b</i>‐poly(ethene‐<i>co</i>‐butadiene)‐<i>b</i>‐polystyrene triblock copolymer adding monodisperse polystyrene The influence of adding narrow molar mass distribution polystyrene (PS) homopolymer on the morphology and/or dewetting processing of polystyrene‐ b ‐poly(ethene‐ co ‐butadiene)‐ b ‐polystyrene triblock copolymer (SEBS) thin films was investigated. The addition of the homopolymer caused a transition from non‐straight ribbons (with regularly spaced necks) to a spherical microdomain structure for an amount of 75 vol% PS (SEBS/PS 1:3), which also shows an interdomain distance increase of three times with respect to the neat SEBS. This spacing and interdomain distance control coincides with the amount of homopolymer added in the blend. The blending with PS demonstrates an approach to fine‐tuning the block copolymer structure and tailoring in‐plane microdomain spacing. Smaller or higher amounts of PS changed the spontaneous patterned structure originally observed for the neat triblock copolymer, resulting in a non‐ordered microphase separation. © 2023 Society of Industrial Chemistry. Copolymer ; Polystyrene ; Materials science ; Dispersity ; Dewetting ; Molar mass ; Polymer chemistry ; Morphology (biology) ; Chemical engineering ; Composite material ; Polymer ; Nanotechnology ; Thin film Block Copolymer Self-Assembly ; Fluid Dynamics and Thin Films ; Rheology and Fluid Dynamics Studies
Authors: Baptiste Amouroux | Ali Eftekhari | Clément Roux | J. C. Micheau | Pierre Roblin | Mathieu Pasturel | Fabienne Gauffre | Christian Würth | Ute Resch‐Genger | Michel Sliwa | Aude Bouchet | Christophe Coudret
Source: ChemRxiv (preprint, 2023-03-13)
Field: Materials Science — Materials Chemistry

Synthesis and emission dynamics of sub-3 nm single-emitter upconversion nanoparticles Reducing the size of upconversion nanoparticles (UCNPs) down to a few nm yields unique luminescent materials containing a very small number of emitters. Considering the bottom limit of one activator per particle, such ultrasmall UCNPs offer an unprecedented platform to study the contributions of the different energy transfer processes at play in upconversion luminescence, especially the role of cross relaxation. Maintaining detectable emission despite the limited number of emitting ions and the high surface-to-volume ratio requires suitable particle architectures. The preparation of Na(Gd-Yb)F4:Tm emissive sub-3 nm diameter -phase UCNPs was achieved using a gadolinium-rich composition, in situ mixing of the precursors NaOH and NH4F, and a microwave high-temperature cycling sequence that allowed precise control of the particle size and dispersity. These nanoparticles contain only a single Tm3+ activator ion, while coating of these cores with a NaGdF4 inert shell was performed to minimize the deleterious influence of surface quenching. The role of cross relaxation in upconversion luminescence was examined by time-resolved luminescence measurements using a combination of standard NIR excitation of the Yb3+ sensitizer and direct UV excitation of the Tm3+ activator. The fine tuning of the number of activators per particle via an optimized synthesis pathway along with an appropriate excitation scheme enabled us to select the operating cross relaxation processes and provide an accurate analysis of the different mechanisms at play in these model nanoparticles. Luminescence ; Materials science ; Photon upconversion ; Nanoparticle ; Activator (genetics) ; Ion ; Analytical Chemistry (journal) ; Particle size ; Excitation ; Fluorescence ; Nanotechnology ; Optoelectronics ; Chemistry ; Physical chemistry ; Optics Luminescence Properties of Advanced Materials ; Inorganic Fluorides and Related Compounds ; Radiation Detection and Scintillator Technologies
Authors: Parsa Hooshyar | Atieh Zamani | Deniz Rezapour Kiani | Shayan Fakhraeelotfabadi | Mehdi Fardmanesh
Source:  (article, 2023-11-15)
Field: Materials Science — Materials Chemistry

Electrical and Optical Properties of Controlled Reduced Graphene Oxide Prepared by a Green and Facile Route Three distinct homogeneous multilayer self-standing thin films, composed of stacked reduced graphene oxide (rGO) planes, were produced by the improved Hummer’s method. In order to investigate their structural, electrical, and optical properties, the samples were characterized by Raman spectroscopy, field emission scanning electron microscopy (FESEM), four-point probe measurements, and Fourier-transform infrared spectroscopy (FTIR). The Raman spectra of the samples indicate the presence of minor surface defects and a relatively low oxygen content of rGOs. The FESEM images obtained from the samples reveal a smooth sheet-like surface with few wrinkles. Additionally, the cross-sectional images provide confirmation of the presence of multi-stacked layer structures. Based on the resistance decreasing by about 0.35 to 0.65 percent per kelvin within the region of ambient temperature, the electrical resistance vs. temperature curves imply semiconducting behavior in the rGOs. The FTIR analysis of the samples conducted within the wavelength range of 2.5 to 25 µm demonstrates a significant absorption value exceeding 90%. This observation shows that the developed materials possess favorable characteristics, making them an excellent absorber candidate for sensing detectors in the infrared range. We systematically analyzed and confirmed that the structural as well as optical and electrical properties of our obtained rGOs may be fine-tuned by adjusting the initial reactants concentration and annealing temperature. Graphene ; Materials science ; Oxide ; Nanotechnology ; Graphene oxide paper ; Optoelectronics ; Chemical engineering ; Metallurgy ; Engineering Graphene research and applications ; Advanced Memory and Neural Computing ; Graphene and Nanomaterials Applications
Authors: Nicolás Moreno-Gómez | Athanasios G. Athanassiadis | Albert T. Poortinga | Peer Fischer
Source: arXiv (Cornell University) (preprint, 2023-05-17)
Field: Materials Science — Materials Chemistry

Antibubbles enable tunable payload release with low-intensity ultrasound The benefits of ultrasound are its ease-of-use and its ability to precisely deliver energy in opaque and complex media. However, most materials responsive to ultrasound show a weak response, requiring the use of high powers, which are associated with undesirable streaming, cavitation, or temperature rise. These effects hinder response control and may even cause damage to the medium where the ultrasound is applied. Moreover, materials that are currently in use rely on all-or-nothing effects, limiting the ability to fine-tune the response of the material on the fly. For these reasons, there is a need for materials that can respond to low intensity ultrasound with programmable responses. Here it is demonstrated that antibubbles are a low-intensity-ultrasound-responsive material system that can controllably release a payload using acoustic pressures in the kPa range. Varying their size and composition tunes the release pressure, and the response can be switched between a single release and stepwise release across multiple ultrasound pulses. Observations using confocal and high-speed microscopy revealed different ways that can lead to release. These findings lay the groundwork to design antibubbles that controllably respond to low-intensity ultrasound, opening a wide range of applications ranging from ultrasound-responsive material systems to carriers for targeted delivery. Ultrasound ; Payload (computing) ; Limiting ; Materials science ; Intensity (physics) ; Opacity ; High-intensity focused ultrasound ; Cavitation ; Focused ultrasound ; Acoustics ; Computer science ; Biomedical engineering ; Optics ; Mechanical engineering ; Engineering ; Physics Ultrasound and Cavitation Phenomena ; Pickering emulsions and particle stabilization ; 3D Printing in Biomedical Research
Authors: С.Л. Гафнер
Source: Physical and Chemical Aspects of the Study of Clusters Nanostructures and Nanomaterials (article, 2023-11-29)
Field: Materials Science — Electronic, Optical and Magnetic Materials

К ВОПРОСУ ПРИМЕНЕНИЯ НАНОКЛАСТЕРОВ Ag-Cu В ПЛАЗМОНИКЕ The magnitude of the localized surface plasmon resonance (LSPR) in metal nanoparticles is determined by many factors. Thus, with an increase in their average linear size, the maximum position of the LSPR peak shifts towards long waves. However, the position of the LSPR maximum is affected to a greater extent by the material of the nanoparticles. Changing the average particle diameter from D = 7 nm to D = 60 nm makes it possible to vary the position of the LSPR maximum in the range of about 50 nm. However, with a smooth change in the composition of binary nanoparticles, it can already be varied within about 120 nm. Therefore, copper-silver alloy nanoparticles are of great practical interest due to the possibility of fine-tuning the plasmonic effects present in them by changing the composition, size, shape, and structure of the nanoparticles. Based on the results of the analysis of the available experimental data, it was concluded that it is possible to control the internal structure and shape of Ag-Cu nanoparticles in order to shift the plasmon resonance peak and enhance it. Materials science ; Environmental science Gold and Silver Nanoparticles Synthesis and Applications ; Plasmonic and Surface Plasmon Research ; Laser-Ablation Synthesis of Nanoparticles
Authors: Tarun M Patel | Khushbu G. Patel | Parasar Modhh
Source: Research Square (preprint, 2023-07-24)
Field: Chemistry — Organic Chemistry

Electrochemical Synthesis of 5-(1H-indol-3-yl) N-Substituted-1,3,4-oxadiazole- 2-Amines: A Mild and Green Approach Abstract The electrochemical method for the synthesis of 5-(1H-indol-3-yl) N-substituted 1,3,4-oxadiazole-2-amines is a novel and efficient approach that offers several advantages over traditional synthetic methods. This method utilizes aliphatic and aromatic isothiocyanates as starting materials and employs electrochemical techniques to facilitate the reaction. The process begins with the selection of an appropriate electrochemical setup, typically involving a two-electrode system consisting of a working electrode and a counter electrode. The working electrode is made of a conductive material such as carbon. The reaction vessel contains a suitable electrolyte, which can be an organic solvent or an ionic liquid, depending on the specific requirements of the reaction. The reaction proceeds by applying a potential across the electrodes, creating an electric field that promotes the desired electrochemical transformations. The indole substrate and the isothiocyanate reagent are introduced into the reaction vessel, and upon the application of the appropriate potential, they undergo electrochemical oxidation and subsequent nucleophilic substitution to form the desired 1,3,4-oxadiazole-2-amines. One of the key advantages of this electrochemical method is its high functional group tolerance. The reaction can accommodate a wide range of functional groups present on both the indole substrate and the isothiocyanate reagents. This allows for the synthesis of diverse compounds with different substituents, providing access to a large substrate scope. Another notable advantage of this method is its good yield of the desired products. The electrochemical conditions can be optimized to ensure high conversion and selectivity, resulting in good overall yields of the 5-(1H-indol-3-yl) N-substituted 1,3,4-oxadiazole-2-amines. The reaction conditions can be fine-tuned to achieve the desired level of selectivity and efficiency. Furthermore, the facile nature of the electrochemical method makes it a convenient and sustainable alternative to traditional synthetic methods. Additionally, the use of electricity as an energy source can be more environmentally friendly compared to traditional heating methods. Electrochemistry ; Ionic liquid ; Reagent ; Oxadiazole ; Substrate (aquarium) ; Chemistry ; Combinatorial chemistry ; Nucleophile ; Yield (engineering) ; Electrode ; Materials science ; Organic chemistry ; Catalysis ; Physical chemistry Synthesis and Biological Evaluation ; Electrochemical sensors and biosensors ; Electrochemical Analysis and Applications
Authors: Cheng Jih | Chih‐Hsien Chen
Source: SSRN Electronic Journal (preprint, 2023-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Role of Π-Bridge and Strong Solid-State Emission in Triphenylamine-Benzothiazole Based Nonlinear Optical Dyes Benzothiazole ; Triphenylamine ; Bridge (graph theory) ; Solid-state ; Nonlinear optical ; Nonlinear system ; State (computer science) ; Optoelectronics ; Photochemistry ; Materials science ; Chemistry ; Computer science ; Physics ; Physical chemistry ; Organic chemistry ; Algorithm ; Quantum mechanics Nonlinear Optical Materials Research ; Nonlinear Optical Materials Studies ; Luminescence and Fluorescent Materials
Authors: Hyun Park | Ruijie Zhu | E. A. Huerta | Santanu Chaudhuri | Emad Tajkhorshid | Donny Cooper
Source: Zenodo (CERN European Organization for Nuclear Research) (article, 2023-03-14)
Field: Materials Science — Materials Chemistry

End-to-end AI Framework for Hyperparameter Optimization, Model Training, and Interpretable Inference for Molecules and Crystals Pretrained models for "End-to-end AI Framework for Hyperparameter Optimization, Model Training, and Interpretable Inference for Molecules and Crystals" paper submitted to MLST journal. Hyperparameter ; Inference ; Artificial intelligence ; Training (meteorology) ; Machine learning ; Computer science ; Physics Machine Learning in Materials Science
Authors: Sara C. Silva-Reis | Vera Marisa Costa | Daniela Correia da Silva | David M. Pereira | Xavier Cruz Correia | Hugo F. Costa-Almeida | Xerardo García‐Mera | José E. Rodríguez‐Borges | Ivo E. Sampaio‐Dias
Source: SSRN Electronic Journal (preprint, 2023-01-01)
Field: Chemistry — Organic Chemistry

Exploring Structural Determinants of Neuroprotection Bias on Novel Glypromate Bioconjugates with Bioactive Amines Neuroprotection ; Nanotechnology ; Neuroscience ; Chemistry ; Business ; Psychology ; Materials science Click Chemistry and Applications ; Protein Degradation and Inhibitors ; Cancer, Hypoxia, and Metabolism