jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Nursamsiar Nursamsiar | Mawaddah Putri Arisma Siregar | Akbar Awaluddin | N. Nurnahari | Syamsu Nur | Ellin Febrina | Aiyi Asnawi
Source: RASAYAN Journal of Chemistry (article, 2020-01-01)
Field: Chemistry — Organic Chemistry

MOLECULAR DOCKING AND MOLECULAR DYNAMIC SIMULATION OF THE AGLYCONE OF CURCULIGOSIDE A AND ITS DERIVATIVES AS ALPHA GLUCOSIDASE INHIBITORS Diabetes mellitus (DM) is characterized by high blood sugar levels caused by insufficient insulin production in the pancreas or insulin resistance in the body. Alpha-glucosidase enzymes are therapeutic targets for type 2 diabetes treatment. Structurally, curculigoside has a resemblance to xathohumol (chalcone) which has a strong inhibitory activity against alpha glucosidase. The present study aims to determine the interaction of the aglycone of curculigoside A and its derivatives against alpha glucoside (PDB ID 2QMJ) was evaluated based on interaction mode and binding stability by performing docking and molecular dynamic simulation by using AutoDock 4.2 and AMBER 18, respectively. All ligands can interact with alpha glycosidase and ligand 34, 36, 43, and 56 have a best binding mode with free bonding energy of -6.30, -5.67, -5.16, and -5.92 kcal/mole, respectively. The hydrogen bonds formed in MD are different from the docked pose because of a large movement of alpha glucoside receptor and ligand during the MD process. In conclusion, ligand 34, 36, 43, and 56 are candidates for lead compounds as alpha glucosidase inhibitors. Aglycone ; Molecular dynamics ; Chemistry ; Stereochemistry ; Docking (animal) ; Combinatorial chemistry ; Computational chemistry ; Medicine ; Glycoside Carbohydrate Chemistry and Synthesis ; Pharmacological Effects of Natural Compounds ; Glycosylation and Glycoproteins Research
Authors: Olusesan K. Koleoso | Matthew A. Turner | Felix Plasser | Marc C. Kimber
Source: Beilstein Journal of Organic Chemistry (article, 2020-08-12)
Field: Chemistry — Organic Chemistry

A complementary approach to conjugated <i>N</i> -acyliminium formation through photoredox-catalyzed intermolecular radical addition to allenamides and allencarbamates An intermolecular radical addition, using photoredox catalysis, to allenamides and allencarbamates is reported. This transformation synthesizes <i>N</i>-acyl-<i>N'</i>-aryl-<i>N</i>,<i>N'</i>-allylaminals, and proceeds by a conjugated <i>N</i>-acyliminium intermediate that previously has principally been generated by electrophilic activation methods. The radical adds to the central carbon of the allene giving a conjugated <i>N</i>-acyliminium that undergoes nucleophilic addition by arylamines and alcohols. Chemistry ; Intermolecular force ; Conjugated system ; Allene ; Electrophile ; Photoredox catalysis ; Catalysis ; Nucleophile ; Aryl ; Nucleophilic addition ; Photochemistry ; Combinatorial chemistry ; Organic chemistry ; Photocatalysis ; Molecule ; Alkyl Radical Photochemical Reactions ; Sulfur-Based Synthesis Techniques ; Catalytic C–H Functionalization Methods
Authors: Soeun Gim | Giulio Fittolani | Yoshiharu Nishiyama | Peter H. Seeberger | Yu Ogawa | Martina Delbianco
Source: Angewandte Chemie (article, 2020-09-02)
Field: Materials Science — Biomaterials

Supramolecular Assembly and Chirality of Synthetic Carbohydrate Materials Abstract Hierarchical carbohydrate architectures serve multiple roles in nature. Hardly any correlations between the carbohydrate chemical structures and the material properties are available due to the lack of standards and suitable analytic techniques. Therefore, designer carbohydrate materials remain highly unexplored, as compared to peptides and nucleic acids. A synthetic D ‐glucose disaccharide, DD , was chosen as a model to explore carbohydrate materials. Microcrystal electron diffraction (MicroED), optimized for oligosaccharides, revealed that DD assembled into highly crystalline left‐handed helical fibers. The supramolecular architecture was correlated to the local crystal organization, allowing for the design of the enantiomeric right‐handed fibers, based on the L ‐glucose disaccharide, LL , or flat lamellae, based on the racemic mixture. Tunable morphologies and mechanical properties suggest the potential of carbohydrate materials for nanotechnology applications. Supramolecular chemistry ; Disaccharide ; Chirality (physics) ; Carbohydrate ; Supramolecular chirality ; Chemistry ; Crystal engineering ; Nanotechnology ; Enantiomer ; Carbohydrate chemistry ; Crystal structure ; Crystallography ; Stereochemistry ; Materials science ; Organic chemistry Supramolecular Self-Assembly in Materials ; Carbohydrate Chemistry and Synthesis ; Bacteriophages and microbial interactions
Authors: Amir Kordijazi | Swaroop Behera | Shvetashva Suri | Zhongying Wang | Marco Povolo | Nathan Salowitz | Pradeep K. Rohatgi
Source: Surfaces and Interfaces (article, 2020-05-20)
Field: Materials Science — Surfaces, Coatings and Films

Data-driven modeling of wetting angle and corrosion resistance of hypereutectic cast Aluminum-Silicon alloys based on physical and chemical properties of surface Materials science ; Wetting ; Contact angle ; Surface roughness ; Silicon ; Eutectic system ; Surface finish ; Aluminium ; Metallurgy ; Factorial experiment ; Corrosion ; Composite material ; Alloy Surface Modification and Superhydrophobicity ; Adhesion, Friction, and Surface Interactions ; Surface Roughness and Optical Measurements
Authors: Baishan Liu | Junli Du | Huihui Yu | Mengyu Hong | Zhuo Kang | Zheng Zhang | Yue Zhang
Source: Nano Research (article, 2020-12-07)
Field: Materials Science — Materials Chemistry

The coupling effect characterization for van der Waals structures based on transition metal dichalcogenides van der Waals (vdW) heterostructures based on two-dimensional (2D) materials holding design-by-demand features offer astonishing opportunities to construct novel electronics and optoelectronics devices due to the vdW force interaction between their stacked components. At the atomically thin confinement, vdW heterostructure not only exhibits unprecedented properties as an entire counterpart, but also provides unique platforms to manipulate the vdW interfacial behaviors. Therefore, developing characterization techniques to comprehensively understand the coupling effect on structure-property-performance relationship of vdW heterostructures is crucial for fundamental science and practical applications. Here, we focus on the most widely studied 2D semiconductor transition metal dichalcogenides (TMDCs) and systematically review significant advances in characterizing the material and interfacial coupling effect of the related vdW heterostructures. Specially, we will discuss microscopy techniques for unveiling the structure-property relationship of vdW heterostructures and optical spectroscopy measurements for analyzing vdW interfacial coupling effect. Finally, we address some promising strategies to optimize characterization technologies for resolving vdW heterostructures, including coupling multiple characterization technologies, improving temporal and spatial resolution, developing fast, efficient, and non-destructive techniques and introducing artificial intelligence. Heterojunction ; Characterization (materials science) ; van der Waals force ; Materials science ; Nanotechnology ; Coupling (piping) ; Semiconductor ; Electronics ; Transition metal ; Optoelectronics ; Chemistry ; Physics ; Molecule ; Quantum mechanics ; Physical chemistry 2D Materials and Applications ; MXene and MAX Phase Materials ; Graphene research and applications
Authors: Xiaoxu Zhao | Kian Ping Loh | Stephen J. Pennycook
Source: Journal of Physics Condensed Matter (article, 2020-10-02)
Field: Materials Science — Materials Chemistry

Electron beam triggered single-atom dynamics in two-dimensional materials Controlling atomic structure and dynamics with single-atom precision is the ultimate goal in nanoscience and nanotechnology. Despite great successes being achieved by scanning tunneling microscopy (STM) over the past a few decades, fundamental limitations, such as ultralow temperature, and low throughput, significantly hinder the fabrication of a large array of atomically defined structures by STM. The advent of aberration correction in scanning transmission electron microscopy (STEM) revolutionized the field of nanomaterials characterization pushing the detection limit down to single-atom sensitivity. The sub-angstrom focused electron beam (e-beam) of STEM is capable of interacting with an individual atom, thereby it is the ideal platform to direct and control matter at the level of a single atom or a small cluster. In this article, we discuss the transfer of energy and momentum from the incident e-beam to atoms and their subsequent potential dynamics under different e-beam conditions in 2D materials, particularly transition metal dichalcogenides (TMDs). Next, we systematically discuss the e-beam triggered structural evolutions of atomic defects, line defects, grain boundaries, and stacking faults in a few representative 2D materials. Their formation mechanisms, kinetic paths, and practical applications are comprehensively discussed. We show that desired structural evolution or atom-by-atom assembly can be precisely manipulated by e-beam irradiation which could introduce intriguing functionalities to 2D materials. In particular, we highlight the recent progress on controlling single Si atom migration in real-time on monolayer graphene along an extended path with high throughput in automated STEM. These results unprecedentedly demonstrate that single-atom dynamics can be realized by an atomically focused e-beam. With the burgeoning of artificial intelligence and big data, we can expect that fully automated microscopes with real-time data analysis and feedback could readily design and fabricate large scale nanostructures with unique functionalities in the near future. Scanning transmission electron microscopy ; Atom (system on chip) ; Materials science ; Nanotechnology ; Scanning tunneling microscope ; Graphene ; Beam (structure) ; Chemical physics ; Transmission electron microscopy ; Physics ; Optics ; Computer science Electronic and Structural Properties of Oxides ; Graphene research and applications ; 2D Materials and Applications
Authors: Hieu T. Nguyen-Truong | Bo Da | Lihao Yang | Zejun Ding | Hideki Yoshikawa | Shigeo Tanuma
Source: Applied Physics Letters (article, 2020-07-20)
Field: Materials Science — Materials Chemistry

Low-energy electron inelastic mean free path for monolayer graphene The electron inelastic mean free path (IMFP) is an important quantity for electron spectroscopy and microscopy techniques. At present, there are very few data of IMFPs for two-dimensional (2D) materials. Here, we determine the IMFP at energies below 100 eV for monolayer graphene both experimentally and theoretically. The experimental determination is based on a data-driven spectral analysis technique, including the virtual substrate method and the reverse Monte Carlo method. The theoretical determination is performed within the dielectric formalism, using the energy-loss function calculated in the time-dependent density functional theory. The experimental and theoretical results show that the IMFP for monolayer graphene is almost constant (about 1 nm) in the energy range of 6–100 eV. This study suggests a general and reliable approach to determine low-energy IMFPs for 2D materials. Inelastic mean free path ; Monolayer ; Mean free path ; Graphene ; Electron ; Materials science ; Electron spectroscopy ; Density functional theory ; Molecular physics ; Atomic physics ; Chemistry ; Physics ; Nanotechnology ; Computational chemistry ; Quantum mechanics Graphene research and applications ; Electron and X-Ray Spectroscopy Techniques ; Surface and Thin Film Phenomena
Authors: Liumei Su | Xing Fan | Cong Wang | Qiong Wu | Yu Li | Han Zhang | Heping Xie
Source: Nanophotonics (article, 2020-02-01)
Field: Materials Science — Materials Chemistry

Advances in photonics of recently developed Xenes Abstract Monoelemental two‐dimensional materials are well known as Xenes. The representatives graphene and phosphorene have received considerable attention because of their outstanding physical properties. In recent years, the family members of Xenes have greatly increased, and the emerging ones are gaining more and more interest. In this review, we mainly focus on the recently developed Xenes in groups IIIA, VA, and VI. Comprehensive discussions of the latest progress are given in the aspects of basic physical properties and intriguing applications in photonics, optoelectronics, energy, and biomedicines. Phosphorene ; Nanotechnology ; Photonics ; Engineering ethics ; Engineering physics ; Graphene ; Materials science ; Computer science ; Engineering ; Optoelectronics 2D Materials and Applications ; MXene and MAX Phase Materials ; Graphene research and applications
Authors: Yusha Liu | Meng Li | Jeffrey S. Morris
Source: The Annals of Applied Statistics (article, 2020-06-01)
Field: Chemistry — Spectroscopy

Function-on-scalar quantile regression with application to mass spectrometry proteomics data Mass spectrometry proteomics, characterized by spiky, spatially heterogeneous functional data, can be used to identify potential cancer biomarkers. Existing mass spectrometry analyses utilize mean regression to detect spectral regions that are differentially expressed across groups. However, given the inter-patient heterogeneity that is a key hallmark of cancer, many biomarkers are only present at aberrant levels for a subset of, not all, cancer samples. Differences in these biomarkers can easily be missed by mean regression, but might be more easily detected by quantile-based approaches. Thus, we propose a unified Bayesian framework to perform quantile regression on functional responses. Our approach utilizes an asymmetric Laplace working likelihood, represents the functional coefficients with basis representations which enable borrowing of strength from nearby locations, and places a global-local shrinkage prior on the basis coefficients to achieve adaptive regularization. Different types of basis transform and continuous shrinkage priors can be used in our framework. A scalable Gibbs sampler is developed to generate posterior samples that can be used to perform Bayesian estimation and inference while accounting for multiple testing. Our framework performs quantile regression and coefficient regularization in a unified manner, allowing them to inform each other and leading to improvement in performance over competing methods as demonstrated by simulation studies. We also introduce an adjustment procedure to the model to improve its frequentist properties of posterior inference. We apply our model to identify proteomic biomarkers of pancreatic cancer that are differentially expressed for a subset of cancer patients compared to the normal controls, which were missed by previous mean-regression based approaches. Supplementary materials for this article are available online. Quantile regression ; Frequentist inference ; Bayesian probability ; Inference ; Quantile ; Regression ; Prior probability ; Bayesian inference ; Shrinkage estimator Advanced Proteomics Techniques and Applications ; Advanced Biosensing Techniques and Applications ; Mass Spectrometry Techniques and Applications
Authors: Anna Bukowski | Leonhard Schill | D.J. Nielsen | Susanne Mossin | Anders Riisager | Jakob Albert
Source: Reaction Chemistry & Engineering (article, 2020-01-01)
Field: Materials Science — Materials Chemistry

NH<sub>3</sub>-SCR of NO with novel active, supported vanadium-containing Keggin-type heteropolyacid catalysts Supported vanadium-substituted Keggin polyoxometalates (POMs) were applied as catalysts for the selective catalytic reduction of NO using NH<sub>3</sub> as reductant (NH<sub>3</sub>-SCR). Vanadium ; Catalysis ; Inorganic chemistry ; Chemistry ; Keggin structure ; Materials science ; Organic chemistry Polyoxometalates: Synthesis and Applications ; Catalysis and Oxidation Reactions ; Chemical Synthesis and Reactions
Authors: Reinier Damman | Alessandra Lucini Paioni | Katerina T. Xenaki | Irati Beltrán Hernández | Paul M.P. van Bergen en Henegouwen | Marc Baldus
Source: Journal of Biomolecular NMR (article, 2020-06-19)
Field: Chemistry — Spectroscopy

Development of in vitro-grown spheroids as a 3D tumor model system for solid-state NMR spectroscopy Recent advances in the field of in-cell NMR spectroscopy have made it possible to study proteins in the context of bacterial or mammalian cell extracts or even entire cells. As most mammalian cells are part of a multi-cellular complex, there is a need to develop novel NMR approaches enabling the study of proteins within the complexity of a 3D cellular environment. Here we investigate the use of the hanging drop method to grow spheroids which are homogenous in size and shape as a model system to study solid tumors using solid-state NMR (ssNMR) spectroscopy. We find that these spheroids are stable under magic-angle-spinning conditions and show a clear change in metabolic profile as compared to single cell preparations. Finally, we utilize dynamic nuclear polarization (DNP)-supported ssNMR measurements to show that low concentrations of labelled nanobodies targeting EGFR (7D12) can be detected inside the spheroids. These findings suggest that solid-state NMR can be used to directly examine proteins or other biomolecules in a 3D cellular microenvironment with potential applications in pharmacological research. Spheroid ; Chemistry ; Nuclear magnetic resonance spectroscopy ; Biomolecule ; Solid-state nuclear magnetic resonance ; Magic angle spinning ; Biophysics ; Context (archaeology) ; Spectroscopy ; Nanotechnology ; In vitro ; Biochemistry ; Nuclear magnetic resonance ; Stereochemistry ; Materials science ; Biology Advanced NMR Techniques and Applications ; Atomic and Subatomic Physics Research ; Advanced MRI Techniques and Applications
Authors: Potejana Potejanasak | Sethavut Duangchan
Source: Crystals (article, 2020-06-23)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Gold Nanoisland Agglomeration upon the Substrate Assisted Chemical Etching Based on Thermal Annealing Process In this study, we proposed the self-organization process and its localized surface plasmon resonance property (LSPR) to study the effect of chemically treated quartz glass substrates for gold nanoisland array formation. Firstly, we etched a quartz glass substrate using a sputter etching machine. Secondly, n-butanol was treated on the surface of the substrate. Then, we deposited a gold thin film on the substrate with assisted chemical etching. Finally, the self-organization method examined the thermal annealing of gold nanoisland arrays on a substrate. The results showed that the gold nanoisland that was aggregated on an etched quartz glass substrate was large and sparse, while the gold nanoisland aggregated on a chemically treated substrate was small and dense. Further, it was revealed that a substrate’s surface energy reduced chemical treating and increased the gold nanoisland contact angle on the substrate via the thermal annealing process. It was also confirmed that chemical treatment was useful to control the morphology of gold nanoisland arrays on a substrate, particularly when related to tuning their optical property. Materials science ; Annealing (glass) ; Isotropic etching ; Surface plasmon resonance ; Substrate (aquarium) ; Nanotechnology ; Etching (microfabrication) ; Thin film ; Chemical engineering ; Optoelectronics ; Composite material ; Layer (electronics) ; Nanoparticle Gold and Silver Nanoparticles Synthesis and Applications ; Plasmonic and Surface Plasmon Research ; Nanomaterials and Printing Technologies
Authors: Samadhan S. Nagane | Peter Sitarik | Yuhang Wu | Quintin Baugh | Shrirang Chhatre | Junghyun Lee | David C. Martin
Source: MRS Advances (article, 2020-01-09)
Field: Materials Science — Polymers and Plastics

Functionalized Polythiophene Copolymers for Electronic Biomedical Devices Materials science ; Polythiophene ; Copolymer ; Monomer ; Polymer ; Thiophene ; PEDOT:PSS ; Conjugated system ; Bifunctional ; Moiety ; Nanotechnology ; Polymer chemistry ; Conductive polymer ; Organic chemistry ; Catalysis ; Chemistry ; Composite material Conducting polymers and applications ; Advanced Sensor and Energy Harvesting Materials ; Neuroscience and Neural Engineering
Authors: Maria Laura Tummino | Leonarda Francesca Liotta | Giuliana Magnacca | Massimiliano Lo Faro | Stefano Trocino | Sabrina Campagna Zignani | A.S. Aricò | Francesca Deganello
Source: Catalysts (article, 2020-01-18)
Field: Materials Science — Materials Chemistry

Sucrose-Assisted Solution Combustion Synthesis of Doped Strontium Ferrate Perovskite-Type Electrocatalysts: Primary Role of the Secondary Fuel The methodologies and experimental conditions used for the synthesis of cathode materials for electrochemical devices strongly influence their electrocatalytic performance. In particular, solution combustion synthesis is a convenient and versatile methodology allowing a fine-tuning of the properties of the material. In this work, we used for the first time a sucrose assisted-solution combustion synthesis for the preparation of Cerium and Cobalt-doped SrFeO3–δ electrocatalysts and we investigated the effect of polyethylene glycol (PEG) addition as a secondary fuel on their structural, microstructural, redox and electrochemical properties. The perovskite-type powders were characterized by X-ray diffraction coupled with Rietveld refinement, scanning, and high-resolution transmission electron microscopies, thermogravimetric analysis, nitrogen adsorption measurements, and temperature-programmed reduction. Electrical conductivity and overpotential measurements were performed after the deposition of the powders onto a Gd-doped ceria electrolyte pellet. Stable high-valence B-site cations were detected in the powders prepared from sucrose-PEG fuel mixtures, although a substantial improvement of the conductivity and a decrease of the overpotential values were obtained only with high molecular weight PEG. The superior electrochemical performance obtained using PEG with high molecular weight has been ascribed to a faster interaction of the powder with the oxygen gas phase favored by the nanometer-sized crystalline domains. Overpotential ; Materials science ; Chemical engineering ; Thermogravimetric analysis ; Electrochemistry ; Inorganic chemistry ; Perovskite (structure) ; Cerium ; Chemistry ; Electrode ; Physical chemistry Advancements in Solid Oxide Fuel Cells ; Electrocatalysts for Energy Conversion ; Advanced battery technologies research