jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Sven M. Elbert | Tobias Kirschbaum | Frank Röminger | Michael Mastalerz
Source: Organic Materials (article, 2021-04-01)
Field: Chemistry — Organic Chemistry

Proving Triptycene Homoconjugation with the Same Chromophore but Different Connectivity to the Core Homoconjugation is a phenomenon discussed for various π-systems where classical conjugation is broken by e.g. methylene units but still a stabilization by electronic communication exists. In this respect, triptycene with its rigid C3 symmetric geometry is an ideal scaffold to study this phenomenon. Although several studies based on triptycene strengthen the hypothesis of homoconjugation, in all described cases the electronic communication through space relies on different π-blades. Here, two triptycenes are presented having the exact same π-extended chromophore, but differently annulated to the bicyclic core. Both compounds were investigated by spectroscopic as well as computational means and compared with the corresponding model compound, elucidating the influence of the attachment site to the triptycene core on potential homoconjugation. Triptycene ; Chromophore ; Core (optical fiber) ; Space (punctuation) ; Chemistry ; Stereochemistry ; Computational chemistry ; Chemical physics ; Materials science ; Photochemistry ; Computer science ; Polymer chemistry Synthesis and Properties of Aromatic Compounds ; Luminescence and Fluorescent Materials ; Supramolecular Chemistry and Complexes
Authors: David Gatineau | Héloïse Dossmann | Hervé Clavier | Antony Memboeuf | László Drahos | Yves Gimbert | Denis Lesage
Source: International Journal of Mass Spectrometry (article, 2021-02-09)
Field: Materials Science — Materials Chemistry

Ligand effects in gold-carbonyl complexes: Evaluation of the bond dissociation energies using blackbody infrared radiative dissociation Dissociation (chemistry) ; Chemistry ; Bond-dissociation energy ; Kinetic energy ; Physical chemistry ; Internal energy ; Black-body radiation ; Ion ; Atomic physics ; Thermodynamics ; Physics ; Radiation Catalytic Processes in Materials Science ; Advanced Chemical Physics Studies ; Machine Learning in Materials Science
Authors: Ryan Peck | Ali Khademi | Juanjuan Ren | Stephen Hughes | Alexandre G. Brolo | Reuven Gordon
Source: Physical Review Research (article, 2021-01-07)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Plasmonic linewidth narrowing by encapsulation in a dispersive absorbing material It is often assumed that adding losses to a resonant system necessarily broadens the width of the resonance. Here, the scattering spectrum of gold nanoparticles in P3HT (strongly absorbing) and PMMA (low loss) were measured using dark field microscopy and surprisingly, the linewidth was halved in the lossy medium. To gain physical insight into this unusual result, a Green function analysis was employed, and the roles of the permittivity, both magnitude and dispersion, in reducing the linewidth when material losses are increased were made clear. This surprising route to narrower linewidths is intriguing for nanoplasmonic applications including sensing, spectroscopy, imaging and nanolasing and also more generally for resonant systems where loss is conventionally avoided. Laser linewidth ; Plasmon ; Scattering ; Photonics ; Optoelectronics ; Condensed matter physics ; Materials science ; Physics ; Optics ; Nanotechnology ; Laser Gold and Silver Nanoparticles Synthesis and Applications ; Plasmonic and Surface Plasmon Research ; Advanced biosensing and bioanalysis techniques
Authors: Sebastian Öhman | Ren Qiu | Tomas Edvinsson | Olof Bäcke | Tobias Törndahl | Mats Boman
Source: Materials Advances (article, 2021-01-01)
Field: Materials Science — Materials Chemistry

Selective kinetic growth and role of local coordination in forming Al<sub>2</sub>TiO<sub>5</sub>-based coatings at lower temperatures Al 2 TiO 5 -based coatings made from aluminium- and titanium-isopropoxide co-deposition using MOCVD, offering reduced temperatures and timescales for its synthesis without binary phase formation. Aluminium ; Materials science ; Titanium ; Metalorganic vapour phase epitaxy ; Deposition (geology) ; Kinetic energy ; Phase (matter) ; Chemical engineering ; Metallurgy ; Nanotechnology ; Chemistry ; Epitaxy Thermal Expansion and Ionic Conductivity ; Magnesium Oxide Properties and Applications ; Microwave Dielectric Ceramics Synthesis
Authors: Cédric Djaou | Christina Villeneuve-Faure | Kremena Makasheva | Laurent Boudou | G. Teyssèdre
Source: Nano Express (article, 2021-11-10)
Field: Materials Science — Materials Chemistry

Analysis of the charging kinetics in silver nanoparticles-silica nanocomposite dielectrics at different temperatures Abstract Dielectric nanocomposite materials are now involved in a large panel of electrical engineering applications ranging from micro-/nano-electronics to power devices. The performances of all these systems are critically dependent on the evolution of the electrical properties of the dielectric parts, especially under temperature increase. In this study we investigate the impact of a single plane of silver nanoparticles (AgNPs), embedded near the surface of a thin silica (SiO 2 ) layer, on the electric field distribution, the charge injection and the charge dynamic processes for different AgNPs-based nanocomposites and various temperatures in the range 25°C–110°C. The electrical charges are injected locally by using an Atomic Force Microscopy (AFM) tip and the related surface potential profile is probed by Kelvin Probe Force Microscopy (KPFM). To get deeper in the understanding of the physical phenomena, the electric field distribution in the AgNPs-based nanocomposites is computed by using a Finite Element Modeling (FEM). The results show a strong electrostatic coupling between the AFM tip and the AgNPs, as well as between the AgNPs when the AgNPs-plane is embedded in the vicinity of the SiO 2 -layer surface. At low temperature (25°C) the presence of an AgNPs-plane close to the surface, i.e., at a distance of 7 nm, limits the amount of injected charges. Besides, the AgNPs retain the injected charges and prevent from charge lateral spreading after injection. When the temperature is relatively high (110°C) the amount of injected charges is increased in the nanocomposites compared to low temperatures. Moreover, the speed of lateral charge spreading is increased for the AgNPs-based nanocomposites. All these findings imply that the lateral charge transport in the nanocomposite structures is favored by the closely situated AgNPs because of the strong electrostatic coupling between them, additionally activated by the temperature increase. Nanocomposite ; Dielectric ; Kelvin probe force microscope ; Electric field ; Materials science ; Silver nanoparticle ; Surface charge ; Nanotechnology ; Nanoparticle ; Composite material ; Analytical Chemistry (journal) ; Optoelectronics ; Atomic force microscopy ; Chemistry ; Physical chemistry ; Physics High voltage insulation and dielectric phenomena ; Advanced Sensor and Energy Harvesting Materials ; Semiconductor materials and devices
Authors: Zongli Wang | Xin Wang | Junlin Wang
Source: Advances in Condensed Matter Physics (article, 2021-07-19)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Research Advance on the Sensing Characteristics of Refractive Index Sensors Based on Electromagnetic Metamaterials Among different sensing platforms, metamaterials composed of subwavelength or deep subwavelength sized metal resonance elements arrays that are etched on semiconductor substrates or dielectric substrates exhibit excellent characteristics due to the strong localization and enhancement of resonance electromagnetic fields. As a new type of detection method, metamaterial sensors can break through the resolution limit of traditional sensors for a small amount of substance and have the advantages of high sensitivity, fast response, and simple measurement. Significant enhancement of the sensing characteristics of metamaterial sensors was realized by optimizing microstructures (single split-ring, double split-ring, nested split-ring, asymmetric split-ring, three-dimensional split-ring, etc.), using ultrathin substrates or low-index substrate materials, etching away local substrate, and integrating microfluidic channel, etc. This paper mainly reviews the research advance on the improvement of sensing characteristics from optimizing resonance structures and changing substrate materials and morphology. Furthermore, the sensing mechanism and main characteristic parameters of metamaterial sensors are introduced in detail, and the development trend and challenge of metamaterial sensing applications are prospected. It is believed that metamaterial sensors will have potential broader application prospects in environmental monitoring, food safety control, and biosensing in the future. Metamaterial ; Materials science ; Substrate (aquarium) ; Optoelectronics ; Split-ring resonator ; Refractive index ; Sensitivity (control systems) ; Etching (microfabrication) ; Nanotechnology ; Dielectric ; Ring (chemistry) ; Optics ; Layer (electronics) ; Electronic engineering ; Physics Metamaterials and Metasurfaces Applications ; Plasmonic and Surface Plasmon Research ; Polydiacetylene-based materials and applications
Authors: Alex Aziz | Javier Carrasco
Source: Frontiers in Chemistry (article, 2021-12-21)
Field: Materials Science — Materials Chemistry

Towards Predictive Synthesis of Inorganic Materials Using Network Science Accelerating materials discovery is the cornerstone of modern technological competitiveness. Yet, the inorganic synthesis of new compounds is often an important bottleneck in this quest. Well-established quantum chemistry and experimental synthesis methods combined with consolidated network science approaches might provide revolutionary knowledge to tackle this challenge. Recent pioneering studies in this direction have shown that the topological analysis of material networks hold great potential to effectively explore the synthesizability of inorganic compounds. In this Perspective we discuss the most exciting work in this area, in particular emerging new physicochemical insights and general concepts on how network science can significantly help reduce the timescales required to discover new materials and find synthetic routes for their fabrication. We also provide a perspective on outstanding problems, challenges and open questions. Bottleneck ; Cornerstone ; Nanotechnology ; Perspective (graphical) ; Computer science ; Data science ; Management science ; Biochemical engineering ; Materials science ; Engineering ; Artificial intelligence Machine Learning in Materials Science ; Computational Drug Discovery Methods ; Complex Network Analysis Techniques
Authors: Fuzhan Rahmanian | Jackson Flowers | Dan Guevarra | Matthias H. Richter | Maximilian Fichtner | John M. Gregoire | Helge S. Stein
Source: ChemRxiv (preprint, 2021-10-13)
Field: Materials Science — Materials Chemistry

Enabling modular autonomous feedback-loops in materials science through hierarchical experimental laboratory automation and orchestration Materials acceleration platforms (MAPs) operate on the paradigm of integrating combinatorial synthesis, high-throughput characterization, automatic analysis, and machine learning. Within these MAPs, one or multiple autonomous feedback loops may aim to optimize materials for certain functional properties or generate new insights. The scope of a given experiment campaign is defined by the range of experiment and analysis actions that are integrated into the experiment framework. Herein we present a method for integrating many actions within a hierarchical experimental laboratory automation and orchestration (HELAO) framework. We demonstrate the capability of orchestrating distributed research instruments that can incorporate data from experiments, simulations, and databases. HELAO interfaces laboratory hardware and software that are distributed across several computers and operating systems for executing experiments, data analysis, provenance tracking, and autonomous planning. Parallelization is an effective approach for accelerating knowledge generation provided that multiple instruments can be effectively coordinated, which we demonstrate with parallel electrochemistry experiments orchestrated by HELAO. Efficient implementation of autonomous research strategies requires device sharing, asynchronous multithreading, and full integration of data management in experiment orchestration, which to the best of our knowledge, is demonstrated for the first time herein. Orchestration ; Computer science ; Modular design ; Distributed computing ; Automation ; Asynchronous communication ; Software ; Interface (matter) ; Modularity (biology) ; Scope (computer science) ; Throughput ; Implementation ; Computer architecture ; Software engineering ; Operating system ; Engineering ; Programming language Machine Learning in Materials Science ; Scientific Computing and Data Management ; Innovative Microfluidic and Catalytic Techniques Innovation
Authors: Moses K. Langat | Teva Kami | Martin Cheek
Source: bioRxiv (Cold Spring Harbor Laboratory) (preprint, 2021-08-22)
Field: Chemistry — Organic Chemistry

Chemistry, Taxonomy and Ecology of the potentially chimpanzee-dispersed <i>Vepris teva</i> sp.nov. (Rutaceae) of coastal thicket in the Congo Republic ABSTRACT Continuing a survey of the chemistry of species of the largely continental African genus Vepris , we investigate a species previously referred to as Vepris sp. 1 of Congo. From the leaves of Vepris sp. 1 we report six compounds. The compounds were three furoquinoline alkaloids, kokusaginine (1) , maculine (2) , and flindersiamine (3) , two acridone alkaloids, arborinine (4) and 1-hydroxy-3-methoxy-10-methylacridone (5) , and the triterpenoid, ß-amyrin (6) . Compounds 1-4 are commonly isolated from other Vepris species, compound 5 has been reported before once, from Malagasy Vepris pilosa , while this is the first report of ß-amyrin from Vepris . This combination of compounds has never before been reported from any species of Vepris . We test the hypothesis that Vepris sp.1 is new to science and formally describe it as Vepris teva , unique in the genus in that the trifoliolate leaves are subsessile, with the median petiolule far exceeding the petiole in length. Similar fleshy-leathery 4-locular syncarpous fruits are otherwise only known in the genus in Vepris glaberrima (formerly the monotypic genus Oriciopsis Engl.), a potential sister species, but requiring further investigation to confirm this phylogenetic position. We briefly characterise the unusual and poorly documented Atlantic coast equatorial ecosystem, where Vepris teva is restricted to evergreen thicket on white sand, unusual in a genus usually confine to evergreen forest. This endemic-rich ecosystem with a unique amphibian as well as plants, extends along the coastline from the mouth of the Congo River to southern Rio Muni, a distance of about 1000 km, traversing five countries. We map and illustrate Vepris teva and assess its extinction risk as Endangered (EN B1ab(iii)+B2ab(iii)) using the IUCN standard. Only three locations are known, and threats include port and oil refinery construction and associated activities, with only one protected location, the Jane Goodall Institute’s Tchimpounga Reserve. Initial evidence indicates that the seeds of Vepris teva are dispersed by chimpanzees, previously unreported in the genus Genus ; Biology ; Ecology ; Botany Chemical synthesis and alkaloids ; Alkaloids: synthesis and pharmacology ; Traditional and Medicinal Uses of Annonaceae
Authors: Gaurav Sharma | Alberto García‐Peñas | Mu. Naushad | Amit Kumar | Mika Sillanpää | Florian J. Stadler
Source: Journal of Chemistry (article, 2021-09-07)
Field: Chemistry — Organic Chemistry

Trimetallic@Cyclodextrin Nanocomposite: Photocatalyst for Degradation of Amoxicillin and Catalyst for Esterification Reactions The industry is looking for new materials which can respond to specific applications that exclusively advance materials can provide. In this context, nanoparticles and nanocomposites opened an interesting method for designing specific properties which can be modulated according to the requirements. The preparation of biomolecules supported trimetallic nanoparticles and some other derives is a good example of the complex systems that can be designed for getting exclusive properties. This study is based on the preparation of new cyclodextrin supported Fe/La/Zn trimetallic nanocomposite by the microemulsion technique. Photocatalytic degradation of amoxicillin was performed using cyclodextrin-Fe/La/Zn. 78% of amoxicillin photodegradation along 4 hours of photoirradiation was achieved. Finally, the catalytic nature of new material was explored for oxidation and esterification reactions. The present study revealed that this advanced multifunctional nanomaterial can be successfully employed for environmental remediation and catalytic activities. Chemistry ; Nanocomposite ; Photodegradation ; Cyclodextrin ; Nanomaterials ; Catalysis ; Photocatalysis ; Context (archaeology) ; Degradation (telecommunications) ; Environmental remediation ; Microemulsion ; Nanoparticle ; Amoxicillin ; Chemical engineering ; Nanotechnology ; Organic chemistry ; Contamination ; Materials science Nanomaterials for catalytic reactions ; TiO2 Photocatalysis and Solar Cells ; Advanced Photocatalysis Techniques
Authors: Akar Doğan | Yılmaz Kismet
Source: International Journal of Pure and Applied Sciences (article, 2021-11-10)
Field: Materials Science — Polymers and Plastics

Gama Işımasının Kolza Takviyeli Polipropilen Kompozit Malzemenin Mekanik Özellikleri Üzerindeki Etkisi Bu araştırmada, kurutulmuş ve toz haline getirilmiş kolza bitkisi takviyeli polipropilen matrisli kompozit malzemenin, çekme, üç nokta eğilme ve Izod darbe mukavemetleri gibi mekanik özellikleri deneysel olarak incelenmiştir. Öncelikle matris malzemesi polipropilen olan ve ağırlıkça %5, %10 ve %20 oranında kolza içeren numuneler ekstrüzyon ve plastik enjeksiyon teknikleri kullanılarak üretilmiştir. Üretilen malzemelerin bir kısmı gama ışımasına tabi tutularak matris ve dolgu malzemesi arasındaki fiziksel bağlanma mekanizması güçlendirilmeye çalışılmıştır. Bu doğrultuda ışıma öncesi ve ışıma sonrası numunelerin mekanik özelliklerindeki değişimler araştırıldı. Yapılan testler sonucunda, çekme ve Izod darbe mukavemetleri, takviye olarak kullanılan kolza miktarının artması ile düştüğü, eğilme mukavemetinin ise arttığı gözlenmiştir. Gama ışımasına maruz bırakılan numunelerin çekme, eğilme ve Izod darbe mukavemetlerinde gama ışımasına maruz bırakılmamış numunelere göre artış meydana geldiği tespit edildi. Physics ; Materials science ; Composite material ; Humanities ; Art Natural Fiber Reinforced Composites ; Tribology and Wear Analysis ; Polymer Foaming and Composites
Authors: Antônio Roniel Marques de Sousa | Marcus Vinícius Alves Nunes | Wellington da Silva Fonseca | Ramon C. F. Araújo | Diorge de Souza Lima
Source: Energies (article, 2021-06-03)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Magneto-Thermo-Structural Analysis of Power Transformers under Inrush and Short Circuit Conditions The main equipment responsible for connection and transmission of electric power from generating centers to consumers are power transformers. This type of equipment is subject to various types of faults that can affect its components, in some cases also compromising its operation and, consequently, the electric power supply. Thus, in this paper, electromagnetic, thermal, and structural analysis of power transformers was carried out with the objective of providing the operator with information on the ideal moment for performing predictive maintenance, avoiding unplanned shutdowns. For this, computational simulations were performed using the finite element method (FEM) and, from that, the different transformer operation ways, nominal currents, inrush current, and short-circuit current were analyzed. In this perspective, analyses of the effects that thermal expansion, axial forces, and radial forces exerted were carried out, contributing to possible defects in this type of equipment. As a study object, simulations were carried out on a 50 MVA single-phase transformer. It is important to emphasize that the simulations were validated with real data of measurements and with results presented in the current literature. Inrush current ; Transformer ; Finite element method ; Engineering ; Electrical engineering ; Power transmission ; Current transformer ; Electronic engineering ; Mechanical engineering ; Power (physics) ; Structural engineering ; Voltage ; Physics Magnetic Properties and Applications ; Power Transformer Diagnostics and Insulation ; Microstructure and Mechanical Properties of Steels
Authors: Matthew K. Matlock | Max Hoffman | Na Le Dang | Dakota Folmsbee | Luke Langkamp | Geoffrey Hutchison | Neeraj Kumar | Kathryn Sarullo | S. Joshua Swamidass
Source: The Journal of Physical Chemistry A (article, 2021-10-05)
Field: Materials Science — Materials Chemistry

Deep Learning Coordinate-Free Quantum Chemistry Computing quantum chemical properties of small molecules and polymers can provide insights valuable into physicists, chemists, and biologists when designing new materials, catalysts, biological probes, and drugs. Deep learning can compute quantum chemical properties accurately in a fraction of time required by commonly used methods such as density functional theory. Most current approaches to deep learning in quantum chemistry begin with geometric information from experimentally derived molecular structures or pre-calculated atom coordinates. These approaches have many useful applications, but they can be costly in time and computational resources. In this study, we demonstrate that accurate quantum chemical computations can be performed without geometric information by operating in the coordinate-free domain using deep learning on graph encodings. Coordinate-free methods rely only on molecular graphs, the connectivity of atoms and bonds, without atom coordinates or bond distances. We also find that the choice of graph-encoding architecture substantially affects the performance of these methods. The structures of these graph-encoding architectures provide an opportunity to probe an important, outstanding question in quantum mechanics: what types of quantum chemical properties can be represented by local variable models? We find that Wave, a local variable model, accurately calculates the quantum chemical properties, while graph convolutional architectures require global variables. Furthermore, local variable Wave models outperform global variable graph convolution models on complex molecules with large, correlated systems. Computer science ; Quantum ; Quantum computer ; Graph ; Quantum chemistry ; Computation ; Theoretical computer science ; Deep learning ; Statistical physics ; Biological system ; Molecule ; Artificial intelligence ; Algorithm ; Quantum mechanics ; Physics Machine Learning in Materials Science ; Computational Drug Discovery Methods ; Protein Structure and Dynamics