jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Yaniv Eliezer | Geyang Qu | Wenhong Yang | Yujie Wang | Hasan Yılmaz | Shumin Xiao | Qinghai Song | Hui Cao
Source: Light Science & Applications (article, 2021-05-19)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Suppressing meta-holographic artifacts by laser coherence tuning A metasurface hologram combines fine spatial resolution and large viewing angles with a planar form factor and compact size. However, it suffers coherent artifacts originating from electromagnetic cross-talk between closely packed meta-atoms and fabrication defects of nanoscale features. Here, we introduce an efficient method to suppress all artifacts by fine-tuning the spatial coherence of illumination. Our method is implemented with a degenerate cavity laser, which allows a precise and continuous tuning of the spatial coherence over a wide range, with little variation in the emission spectrum and total power. We find the optimal degree of spatial coherence to suppress the coherent artifacts of a meta-hologram while maintaining the image sharpness. This work paves the way to compact and dynamical holographic displays free of coherent defects. Coherence (philosophical gambling strategy) ; Holography ; Optics ; Planar ; Laser ; Spatial coherence ; Coherence time ; Coherence theory ; Coherence length ; Computer science ; Spatial frequency ; Image resolution ; Physics ; Computer graphics (images) Metamaterials and Metasurfaces Applications ; Advanced Optical Imaging Technologies ; Liquid Crystal Research Advancements
Authors: Hilal Daglar | İlknur Eruçar | Seda Keskın
Source: Materials Advances (review, 2021-01-01)
Field: Chemistry — Inorganic Chemistry

Recent advances in simulating gas permeation through MOF membranes In the last two decades, metal organic frameworks (MOFs) have gained increasing attention in membrane-based gas separations due to their tunable structural properties. Computational methods play a critical role in providing molecular-level information about the membrane properties and identifying the most promising MOF membranes for various gas separations. In this review, we discuss the current state-of-the-art in molecular modeling methods to simulate gas permeation through MOF membranes and review the recent advancements. We finally address current opportunities and challenges of simulating gas permeation through MOF membranes to guide the development of high-performance MOF membranes in the future. Permeation ; Membrane ; Gas separation ; Materials science ; Chemical engineering ; Chemistry ; Engineering Metal-Organic Frameworks: Synthesis and Applications ; Membrane Separation and Gas Transport ; Covalent Organic Framework Applications
Authors: Balázs L. Tóth | Anna Monory | Orsolya Egyed | Attila Domján | Attila Bényei | Bálint Szathury | Zoltán Novàk | András Stirling
Source: Chemical Science (article, 2021-01-01)
Field: Chemistry — Organic Chemistry

The ortho effect in directed C–H activation The success of transition metal-catalysed <i>ortho</i>-directed C-H activation is often plagued by the effects of undesirable interactions between the directing group (DG) and other groups introduced into the aromatic core of the substrate. In particular, when these groups are in neighbouring positions, their interactions can affect profoundly the efficacy of the C-H activation by transition metals. In this work we introduce a simple <i>substrate-only-based</i> model to interpret the influence of steric hindrance of a group in <i>ortho</i> position to the DG in directed <i>ortho</i>-C-H bond activation reactions, and coined the term Ortho Effect (OE) for such situations. We consider simple descriptors such as torsion angle and torsional energy to predict and explain the reactivity of a given substrate in directed C-H activation reactions. More than 250 examples have been invoked for the model, and the nature of the ortho effect was demonstrated on a wide variety of structures. In order to guide organic chemists, we set structural and energetic criteria to evaluate <i>a priori</i> the efficiency of the metalation step which is usually the rate-determining event in C-H activations, <i>i.e.</i> we provide a simple and general protocol to estimate the reactivity of a potential substrate in C-H activation. For borderline cases these criteria help set the minimum reaction temperature to obtain reasonable reaction rates. As an example for the practical applicability of the model, we performed synthetic validations <i>via</i> palladium-catalysed 2,2,2-trifluoroethylation reactions in our lab. Furthermore, we give predictions for the necessary reaction conditions for several selected DGs. Chemistry ; Steric effects ; Reactivity (psychology) ; Activation energy ; A priori and a posteriori ; Computational chemistry ; Metalation ; Reaction mechanism ; Stereochemistry ; Catalysis ; Organic chemistry Catalytic C–H Functionalization Methods ; Cyclopropane Reaction Mechanisms ; Synthesis and Catalytic Reactions
Authors: Meifang Liu | Kequan Wang | Hanlu Wang | Jie Lu | Shukang Xu | Lulu Zhao | Xilong Wang | Junming Du
Source: RSC Advances (article, 2021-01-01)
Field: Chemistry — Spectroscopy

Simple and sensitive colorimetric sensors for the selective detection of Cu(<scp>ii</scp>) A simple, sensitive colorimetric probe for detecting Cu(ii) ions with fast response has been established with a detection limit of 2.82 μM. UV-Vis spectroscopy along with metal ion response, selectivity, stoichiometry, competition was investigated. In the presence of copper(ii), the UV-Vis spectrum data showed significant changes and the colorimetric detection showed a color change from colorless to yellow. After the selective binding of receptor L with Cu(ii), the UV-visible absorption at 355 nm decreased dramatically, a new absorbance band appeared at 398 nm and its intensity enhanced with the increase in the amount of Cu(ii). Moreover, it exhibited highly selective and sensitive recognition towards Cu(ii) ions in the presence of other cations over the pH range of 7-11. The complex structure was verified by FT-IR spectroscopy, elemental analysis and quantum mechanical calculations using B3LYP/6-31G(d) to illustrate the complex formation between L and Cu(ii). According to the Job plot and the quantum mechanical calculations, the stoichiometric ratio for the complex formation was proposed to be 1 : 1. Chemistry ; Simple (philosophy) ; Ion ; Colorimetry ; Chromatography ; Organic chemistry Molecular Sensors and Ion Detection ; Advanced biosensing and bioanalysis techniques ; Advanced Nanomaterials in Catalysis
Authors: Riccardo Deidda | Florentin Coppey | Dhouha Damergi | C. Schelling | Laureen Coïc | Jean‐Luc Veuthey | Pierre‐Yves Sacré | Charlotte De Bleye | Philippe Hubert | Pierre Esseiva | Eric Ziémons
Source: Journal of Pharmaceutical and Biomedical Analysis (article, 2021-05-19)
Field: Chemistry — Analytical Chemistry

New perspective for the in-field analysis of cannabis samples using handheld near-infrared spectroscopy: A case study focusing on the determination of Δ9-tetrahydrocannabinol Chemistry ; Near-infrared spectroscopy ; Mobile device ; Cannabis ; Partial least squares regression ; Homogeneous ; Mean squared error ; Analytical Chemistry (journal) ; Chromatography ; Statistics ; Computer science ; Mathematics ; Optics Spectroscopy and Chemometric Analyses ; Metabolomics and Mass Spectrometry Studies ; Advanced Chemical Sensor Technologies
Authors: Sergey N. Podyachev | Rustem Zairov | Asiya R. Mustafina
Source: Molecules (review, 2021-02-24)
Field: Materials Science — Materials Chemistry

1,3-Diketone Calix[4]arene Derivatives—A New Type of Versatile Ligands for Metal Complexes and Nanoparticles The present review is aimed at highlighting outlooks for cyclophanic 1,3-diketones as a new type of versatile ligands and building blocks of the nanomaterial for sensing and bioimaging. Thus, the main synthetic routes for achieving the structural diversity of cyclophanic 1,3-diketones are discussed. The structural diversity is demonstrated by variation of both cyclophanic backbones (calix[4]arene, calix[4]resorcinarene and thiacalix[4]arene) and embedding of different substituents onto lower or upper macrocyclic rims. The structural features of the cyclophanic 1,3-diketones are correlated with their ability to form lanthanide complexes exhibiting both lanthanide-centered luminescence and magnetic relaxivity parameters convenient for contrast effect in magnetic resonance imaging (MRI). The revealed structure-property relationships and the applicability of facile one-pot transformation of the complexes to hydrophilic nanoparticles demonstrates the advantages of 1,3-diketone calix[4]arene ligands and their complexes in developing of nanomaterials for sensing and bioimaging. Lanthanide ; Resorcinarene ; Nanomaterials ; Calixarene ; Nanoparticle ; Chemistry ; Combinatorial chemistry ; Metal ; Diketone ; Luminescence ; Nanotechnology ; Molecule ; Materials science ; Stereochemistry ; Organic chemistry Lanthanide and Transition Metal Complexes ; Supramolecular Chemistry and Complexes ; Luminescence and Fluorescent Materials
Authors: Xinyu Wu | Feng Yang | Jian Gan | Zhangqian Kong | Yan Wu
Source: Nanomaterials (article, 2021-07-23)
Field: Materials Science — Surfaces, Coatings and Films

A Superhydrophobic, Antibacterial, and Durable Surface of Poplar Wood The silver particles were grown in situ on the surface of wood by the silver mirror method and modified with stearic acid to acquire a surface with superhydrophobic and antibacterial properties. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and X-ray energy spectroscopy (XPS) were used to analyze the reaction mechanism of the modification process. Scanning electron microscopy (SEM) and contact angle tests were used to characterize the wettability and surface morphology. A coating with a micro rough structure was successfully constructed by the modification of stearic acid, which imparted superhydrophobicity and antibacterial activity to poplar wood. The stability tests were performed to discuss the stability of its hydrophobic performance. The results showed that it has good mechanical properties, acid and alkali resistance, and UV stability. The durability tests demonstrated that the coating has the function of water resistance and fouling resistance and can maintain the stability of its hydrophobic properties under different temperatures of heat treatment. Contact angle ; Materials science ; Wetting ; Fourier transform infrared spectroscopy ; Stearic acid ; Scanning electron microscope ; Coating ; Surface modification ; Chemical engineering ; Composite material ; Surface energy ; Fouling ; Chemistry Surface Modification and Superhydrophobicity ; Textile materials and evaluations ; Pickering emulsions and particle stabilization
Authors: Eugeny V. Alexandrov | Alexander P. Shevchenko | Nadezhda A. Nekrasova | Vladislav A. Blatov
Source: Russian Chemical Reviews (article, 2021-08-23)
Field: Chemistry — Inorganic Chemistry

Topological methods for analysis and design of coordination polymers A comprehensive review of the methods for topological analysis of crystalline compounds as applied to the structures of coordination polymers is presented for the first time. The basic concepts of reticular chemistry, a new branch of science, which combines methods of synthetic chemistry with methods for topological design of polymer compounds, are considered. Reticular chemistry methods are illustrated with examples of the analysis and design of coordination polymers. The most complete classification of coordination polymers, which are similar in terms of various compositional and topological parameters, is given. This review describes and integrates information on the topological analysis tools, such as computer software and electronic databases. A special attention is paid to the application of topological methods in the machine analysis and the prediction of structures and properties of coordination polymers, in particular to the establishment of chemical composition–structure–property relationships and the development of knowledge bases and artificial intelligence systems. A procedure for the search for the general crystal-chemical features using automatic heuristic analysis of large sets of structural data is discussed. It is shown how this analysis can be used to determine the limits of applicability of reticular chemistry and the possibility of its extension to coordination polymers containing structurally, chemically and topologically complex building units with high conformational flexibility. Approaches of reticular chemistry are considered in detail in relation to the design of proton-conductive coordination polymers, which have received considerable attention in the past decade. The specific features of the topological structures of this class of compounds are described in a systematic way. The relationships between the chemical composition, structure and conductive properties of these compounds and the applicability of targeted design are discussed.&lt;br&gt; The bibliography includes 303 references. Chemistry ; Polymer ; Topology (electrical circuits) ; Nanotechnology ; Organic chemistry ; Combinatorics Metal-Organic Frameworks: Synthesis and Applications ; Polyoxometalates: Synthesis and Applications ; Crystallography and molecular interactions
Authors: Yun Zhang | Xiaojie Xu
Source: Structural Chemistry (article, 2021-01-07)
Field: Materials Science — Materials Chemistry

Machine learning lattice constants of zircon-group minerals MXO4 Electronegativity ; Lattice constant ; Chemistry ; Tetragonal crystal system ; Ionic radius ; Ionic bonding ; Zircon ; Lattice (music) ; Stoichiometry ; Crystal structure ; Physical chemistry ; Crystallography ; Ion ; Geology ; Physics ; Geochemistry ; Optics Machine Learning in Materials Science ; Advancements in Solid Oxide Fuel Cells ; X-ray Diffraction in Crystallography
Authors: Marianna V. Kharlamova | Christian Kramberger
Source: Nanomaterials (review, 2021-10-27)
Field: Materials Science — Materials Chemistry

Applications of Filled Single-Walled Carbon Nanotubes: Progress, Challenges, and Perspectives Single-walled carbon nanotubes (SWCNTs), which possess electrical and thermal conductivity, mechanical strength, and flexibility, and are ultra-light weight, are an outstanding material for applications in nanoelectronics, photovoltaics, thermoelectric power generation, light emission, electrochemical energy storage, catalysis, sensors, spintronics, magnetic recording, and biomedicine. Applications of SWCNTs require nanotube samples with precisely controlled and customized electronic properties. The filling of SWCNTs is a promising approach in the fine-tuning of their electronic properties because a large variety of substances with appropriate physical and chemical properties can be introduced inside SWCNTs. The encapsulation of electron donor or acceptor substances inside SWCNTs opens the way for the Fermi-level engineering of SWCNTs for specific applications. This paper reviews the recent progress in applications of filled SWCNTs and highlights challenges that exist in the field. Carbon nanotube ; Nanotechnology ; Materials science ; Nanoelectronics ; Carbon nanotube actuators ; Photovoltaics ; Supercapacitor ; Electronics ; Spintronics ; Optical properties of carbon nanotubes ; Nanotube ; Electrochemistry ; Electrode ; Photovoltaic system ; Electrical engineering ; Engineering ; Chemistry Carbon Nanotubes in Composites ; Graphene research and applications ; Fullerene Chemistry and Applications
Authors: Rebeckah Burke | Kara L. Bren | Todd D. Krauss
Source: The Journal of Chemical Physics (article, 2021-01-15)
Field: Materials Science — Materials Chemistry

Semiconductor nanocrystal photocatalysis for the production of solar fuels Colloidal semiconducting nanocrystals (NCs) are powerful elements of a photocatalytic system useful for enabling a variety of chemical transformations owing to their strong light-absorbing properties and high degree of size-, shape-, and composition-tunability. Key to their utility is our understanding of the photoinduced charge transfer processes required for these photochemical transformations. This Perspective will focus on the implementation of semiconductor NCs for photochemical fuel formation. Three general system designs for photocatalytic proton reduction using semiconductor NCs will be reviewed: metal-semiconductor heterostructures, NC photosensitizers with molecular catalysts, and hydrogenase-based systems. Other relevant reactions toward solar fuel targets, such as CO<sub>2</sub> and N<sub>2</sub> reductions with NCs, will also be highlighted. Illustrating the versatile roles that NCs can play in light-driven chemical reactions, advances made toward NC-catalyzed organic transformations will be discussed. Finally, we will share a few concluding thoughts and perspectives on the future of the field, with a focus on goals toward improving and implementing NC-based technologies for solar fuel development. Photocatalysis ; Solar fuel ; Nanocrystal ; Heterojunction ; Nanotechnology ; Semiconductor ; Materials science ; Catalysis ; Chemistry ; Optoelectronics ; Organic chemistry Quantum Dots Synthesis And Properties ; Advanced Photocatalysis Techniques ; Copper-based nanomaterials and applications
Authors: Yazhou Wang | Amer Hamidi‐Sakr | Jokūbas Surgailis | Yecheng Zhou | Hailiang Liao | Junxin Chen | Genming Zhu | Zhengke Li | Sahika Inal | Wan Yue
Source: Journal of Materials Chemistry C (article, 2021-01-01)
Field: Materials Science — Polymers and Plastics

The effect of the donor moiety of DPP based polymers on the performance of organic electrochemical transistors Two D–A type polymers based on the gTDPP as the acceptor and gTVT and gTBTT as the donor have been developed. The donor unit affects the backbone curvature and the aggregation properties of the mixed conductors, regulating their performance in OECTs. Moiety ; Materials science ; Electrochemistry ; Polymer ; Acceptor ; Transistor ; Curvature ; Electrical conductor ; Conductive polymer ; Polymer chemistry ; Chemical engineering ; Nanotechnology ; Stereochemistry ; Electrode ; Composite material ; Chemistry ; Physical chemistry ; Electrical engineering Conducting polymers and applications ; Organic Electronics and Photovoltaics ; Advanced Sensor and Energy Harvesting Materials
Authors: Marco Beaumont | Caio G. Otoni | Bruno D. Mattos | Tetyana V. Koso | Roozbeh Abidnejad | Bin Zhao | Anett Kondor | Alistair W. T. King | Orlando J. Rojas
Source: Green Chemistry (article, 2021-01-01)
Field: Materials Science — Biomaterials

Regioselective and water-assisted surface esterification of never-dried cellulose: nanofibers with adjustable surface energy A new regioselective route is introduced for surface modification of biological colloids in the presence of water. Taking the case of cellulose nanofibers (CNFs), we demonstrate a site-specific (93% selective) reaction between the primary surface hydroxyl groups (C6-OH) of cellulose and acyl imidazoles. CNFs bearing C6-acetyl and C6-isobutyryl groups, with a degree of substitution of up to 1 mmol g<sup>-1</sup> are obtained upon surface esterification, affording CNFs of adjustable surface energy. The morphological and structural features of the nanofibers remain largely unaffected, but the regioselective surface reactions enable tailoring of their interfacial interactions, as demonstrated in oil/water Pickering emulsions. Our method precludes the need for drying or exchange with organic solvents for surface esterification, otherwise needed in the synthesis of esterified colloids and polysaccharides. Moreover, the method is well suited for application at high-solid content, opening the possibility for implementation in reactive extrusion and compounding. The proposed acylation is introduced as a sustainable approach that benefits from the presence of water and affords a high chemical substitution selectivity. Regioselectivity ; Cellulose ; Nanofiber ; Surface modification ; Acylation ; Chemical engineering ; Chemistry ; Colloid ; Organic chemistry ; Surface energy ; Selectivity ; Materials science ; Polymer chemistry ; Catalysis ; Nanotechnology Advanced Cellulose Research Studies ; Pickering emulsions and particle stabilization ; biodegradable polymer synthesis and properties
Authors: Isabelle Huynen
Source: Micro (article, 2021-07-26)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Investigation of Microwave Absorption Mechanisms in Microcellular Foamed Conductive Composites The paper investigates the mechanisms of microwave absorption in microcellular foamed conductive composites dedicated to protection against electromagnetic interferences (EMI). A multi-layered electromagnetic one-dimensional (1D) model mimicking the microcellular foam structure is built and validated using previous measurements carried out on various fabricated composite foams. Our model enables us to perform a parametric analysis of the absorption behaviour in a foamed composite, using as parameters the size of the hollow cell, the thickness of the cell’s walls and its conductivity, as well as the overall thickness of the composite and the frequency. Our investigations demonstrate that multiple reflections of the microwave signal between the cellular walls are not the main mechanism responsible for absorption, although they are often reported as a cause of enhanced absorption in the literature. On the contrary, our work demonstrates that the enhancement of the absorption observed in foamed conductive composite compared to unfoamed composite is mainly due to the presence of air in the microcells of the composite. Materials science ; Composite number ; Composite material ; Microwave ; Electrical conductor ; Absorption (acoustics) ; EMI ; Conductivity ; Parametric statistics ; Electromagnetic interference ; Electronic engineering ; Telecommunications ; Computer science Electromagnetic wave absorption materials ; Advanced Antenna and Metasurface Technologies ; Metamaterials and Metasurfaces Applications
Authors: Alberto Rumi | Luca Lusuardi | Andrea Cavallini | Marco Pastura | Davide Barater | Stefano Nuzzo
Source: IEEE Access (article, 2021-01-01)
Field: Materials Science — Materials Chemistry

Partial Discharges in Electrical Machines for the More Electrical Aircraft. Part III: Preventing Partial Discharges In this paper, the results obtained from lab tests on twisted pairs subjected to different voltage waveforms and atmospheric conditions are used to propose how to modify the IEC Std. 60034-18-41. The goal is to make the standard suitable for the More Electrical Aircraft (MEA). The results show that it is initially necessary to screen out materials through simple tests. The enhancement factors for temperature can be modified to consider reduced pressures and temperatures using a simple model. The aging enhancement factor can be reduced considering the reduced sensitivity of the partial discharge inception voltage (PDIV) at low pressures on the enamel thickness. Eventually, reference will be made to the drive discussed in Part I of this series to draw conclusions about the likelihood of partial discharge inception in a random wound stator and how to reduce it by modifying either the inverter or the stator insulation. Reference to a random wound motor is made throughout the paper. Partial discharge ; Stator ; Waveform ; Voltage ; Computer science ; Simple (philosophy) ; Sensitivity (control systems) ; Materials science ; Insulation system ; Automotive engineering ; Acoustics ; Electrical engineering ; Mechanical engineering ; Electronic engineering ; Engineering ; Composite material ; Physics High voltage insulation and dielectric phenomena ; Silicon Carbide Semiconductor Technologies ; Electrostatic Discharge in Electronics