jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Joshua Agar | Ye Cao | Brett Naul | Shishir Pandya | Stéfan van der Walt | Aileen Luo | Joshua Maher | Nina Balke | Stephen Jesse | Sergei V. Kalinin | Rama K. Vasudevan | Lane W. Martin
Source: Advanced Materials (article, 2018-05-28)
Field: Materials Science — Materials Chemistry

Machine Detection of Enhanced Electromechanical Energy Conversion in PbZr<sub>0.2</sub>Ti<sub>0.8</sub>O<sub>3</sub> Thin Films Many energy conversion, sensing, and microelectronic applications based on ferroic materials are determined by the domain structure evolution under applied stimuli. New hyperspectral, multidimensional spectroscopic techniques now probe dynamic responses at relevant length and time scales to provide an understanding of how these nanoscale domain structures impact macroscopic properties. Such approaches, however, remain limited in use because of the difficulties that exist in extracting and visualizing scientific insights from these complex datasets. Using multidimensional band-excitation scanning probe spectroscopy and adapting tools from both computer vision and machine learning, an automated workflow is developed to featurize, detect, and classify signatures of ferroelectric/ferroelastic switching processes in complex ferroelectric domain structures. This approach enables the identification and nanoscale visualization of varied modes of response and a pathway to statistically meaningful quantification of the differences between those modes. Among other things, the importance of domain geometry is spatially visualized for enhancing nanoscale electromechanical energy conversion. Materials science ; Microelectronics ; Nanoscopic scale ; Ferroelectricity ; Domain (mathematical analysis) ; Hyperspectral imaging ; Workflow ; Visualization ; Energy (signal processing) ; Nanotechnology ; Computer science ; Artificial intelligence ; Optoelectronics ; Physics ; Dielectric Ferroelectric and Piezoelectric Materials ; Ultrasonics and Acoustic Wave Propagation ; Geophysical and Geoelectrical Methods
Authors: Weiran Song | Hui Wang | Paul Maguire | Omar Nibouche
Source: Chemometrics and Intelligent Laboratory Systems (article, 2018-08-20)
Field: Chemistry — Analytical Chemistry

Collaborative representation based classifier with partial least squares regression for the classification of spectral data Support vector machine ; Artificial intelligence ; Pattern recognition (psychology) ; Partial least squares regression ; Computer science ; Linear discriminant analysis ; Classifier (UML) ; Machine learning ; Regression ; Random forest ; Least squares support vector machine ; Kernel method ; Data mining ; Mathematics ; Statistics Spectroscopy and Chemometric Analyses ; Advanced Chemical Sensor Technologies ; Water Quality Monitoring and Analysis
Authors: Lijun Wang | Hui Yin | Kun Jiang | Guo Yin | Jue Wang | Yan Yan | Yang Wang | Jing Li | Ping Wang | BI Kai-shun | Tiejie Wang
Source: Journal of Pharmaceutical and Biomedical Analysis (article, 2018-07-20)
Field: Chemistry — Analytical Chemistry

Potential of near infrared spectroscopy and pattern recognition for rapid discrimination and quantification of Gleditsia sinensis thorn powder with adulterants Pattern recognition (psychology) ; Normalization (sociology) ; Artificial intelligence ; Chemistry ; Smoothing ; Support vector machine ; Partial least squares regression ; Correlation coefficient ; Second derivative ; Mathematics ; Biological system ; Statistics ; Computer science Spectroscopy and Chemometric Analyses ; Spectroscopy Techniques in Biomedical and Chemical Research ; Essential Oils and Antimicrobial Activity
Authors: Abdolhossein Hemmati‐Sarapardeh | Forough Ameli | Amir Varamesh | Shahaboddin Shamshirband | Amir H. Mohammadi | Bahram Dabir
Source: International Journal of Hydrogen Energy (article, 2018-01-09)
Field: Chemistry — Spectroscopy

Toward generalized models for estimating molecular weights and acentric factors of pure chemical compounds Acentric factor ; Computer science ; Boiling point ; Leverage (statistics) ; Radial basis function ; Artificial neural network ; Algorithm ; Biological system ; Applied mathematics ; Mathematics ; Thermodynamics ; Machine learning ; Physics Analytical Chemistry and Chromatography ; Computational Drug Discovery Methods ; Chemical Thermodynamics and Molecular Structure
Authors: Ron Wurtz | Brenton Blair | Cliff Chen | A. Glenn | Alan D. Kaplan | Paul Rosenfield | J. Ruz | Lance M. Simms
Source: Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment (article, 2018-06-02)
Field: Chemistry — Analytical Chemistry

Methodology and performance comparison of statistical learning pulse shape classifiers as demonstrated with organic liquid scintillator Scintillator ; Pulse (music) ; Liquid scintillation counting ; Materials science ; Statistical learning ; Artificial intelligence ; Computer science ; Pattern recognition (psychology) ; Optics ; Physics ; Chemistry ; Chromatography ; Detector Spectroscopy and Chemometric Analyses ; Fault Detection and Control Systems ; Advanced Chemical Sensor Technologies
Authors: Erdal Dіnç | Zehra Yazan
Source: Frontiers in Chemistry (review, 2018-10-26)
Field: Chemistry — Analytical Chemistry

Wavelet Transform-Based UV Spectroscopy for Pharmaceutical Analysis In research and development laboratories, chemical or pharmaceutical analysis has been carried out by evaluating sample signals obtained from instruments. However, the qualitative and quantitative determination based on raw signals may not be always possible due to sample complexity. In such cases, there is a need for powerful signal processing methodologies that can effectively process raw signals to get correct results. Wavelet transform is one of the most indispensable and popular signal processing methods currently used for noise removal, background correction, differentiation, data smoothing and filtering, data compression and separation of overlapping signals etc. This review article describes the theoretical aspects of wavelet transform (i.e. discrete, continuous and fractional) and its characteristic applications in UV spectroscopic analysis of pharmaceuticals. Smoothing ; Signal processing ; Wavelet transform ; Wavelet ; Computer science ; SIGNAL (programming language) ; Discrete wavelet transform ; Sample (material) ; Raw data ; Artificial intelligence ; Noise (video) ; Pattern recognition (psychology) ; Process (computing) ; Digital signal processing ; Computer vision ; Chemistry ; Chromatography ; Image (mathematics) Spectroscopy and Chemometric Analyses ; Spectroscopy Techniques in Biomedical and Chemical Research ; Water Quality Monitoring and Analysis
Authors: Jenny Jyrkänkallio‐Mikkola | Mika Siljander | Vuokko Heikinheimo | Petri Pellikka | Janne Soininen
Source: Ecological Indicators (article, 2018-07-25)
Field: Materials Science — Biomaterials

Tropical stream diatom communities – The importance of headwater streams for regional diversity Diatom ; Species richness ; Ecology ; Beta diversity ; STREAMS ; Biodiversity ; Benthic zone ; Habitat ; Environmental science ; Dominance (genetics) ; Defaunation ; Geography ; Biology Diatoms and Algae Research ; Freshwater macroinvertebrate diversity and ecology ; Fish Ecology and Management Studies
Authors: Mürsel Karadas | Adam M. Wojciechowski | Alexander Huck | Nils Ole Dalby | Ulrik L. Andersen | Axel Thielscher
Source: Scientific Reports (article, 2018-03-08)
Field: Materials Science — Materials Chemistry

Feasibility and resolution limits of opto-magnetic imaging of neural network activity in brain slices using color centers in diamond We suggest a novel approach for wide-field imaging of the neural network dynamics of brain slices that uses highly sensitivity magnetometry based on nitrogen-vacancy (NV) centers in diamond. In-vitro recordings in brain slices is a proven method for the characterization of electrical neural activity and has strongly contributed to our understanding of the mechanisms that govern neural information processing. However, this traditional approach only acquires signals from a few positions, which severely limits its ability to characterize the dynamics of the underlying neural networks. We suggest to extend its scope using NV magnetometry-based imaging of the neural magnetic fields across the slice. Employing comprehensive computational simulations and theoretical analyses, we determine the spatiotemporal characteristics of the neural fields and the required key performance parameters of an NV magnetometry-based imaging setup. We investigate how the technical parameters determine the achievable spatial resolution for an optimal 2D reconstruction of neural currents from the measured field distributions. Finally, we compare the imaging of neural slice activity with that of a single planar pyramidal cell. Our results suggest that imaging of slice activity will be possible with the upcoming generation of NV magnetic field sensors, while single-shot imaging of planar cell activity remains challenging. Diamond ; Artificial neural network ; Computer science ; Resolution (logic) ; Remote sensing ; Artificial intelligence ; Materials science ; Geology Diamond and Carbon-based Materials Research ; Functional Brain Connectivity Studies ; Photoreceptor and optogenetics research
Authors: Frederick Lia | A. Morote Castellano | Marion Zammit-Mangion | Claude Farrugia
Source: Journal of Food Science and Technology (article, 2018-03-24)
Field: Chemistry — Analytical Chemistry

Application of fluorescence spectroscopy and chemometric models for the detection of vegetable oil adulterants in Maltese virgin olive oils Partial least squares regression ; Sunflower oil ; Vegetable oil ; Olive oil ; Mathematics ; Chemometrics ; Principal component analysis ; Food science ; Sunflower ; Linseed oil ; Chemistry ; Biological system ; Analytical Chemistry (journal) ; Chromatography ; Statistics ; Biology Spectroscopy and Chemometric Analyses ; Edible Oils Quality and Analysis ; Water Quality Monitoring and Analysis
Authors: Michał Kunicki | A. Cichoń
Source: Archives of Acoustics (article, 2018-06-15)
Field: Materials Science — Materials Chemistry

Application of a Phase Resolved Partial Discharge Pattern Analysis for Acoustic Emission Method in High Voltage Insulation Systems Diagnostics An alternative method for analysis of acoustic emission (AE) signals generated by partial discharges (PD), based on a correlation between voltage phase run and AE pulses, so called phase resolved PD pattern (PRPD), is presented in the paper. PRPD pattern is a well-known analysis tool commonly used in such PD diagnostic methods as conventional electrical and UHF ones. Moreover, it yields various signal analysis abilities and allows a direct correlation indication between measurement results achieved using different methods. An original PRPD measurement methodology applied for AE method as well as some exemplary measurement results and further data analysis capabilities are presented in the paper. Also a comparative analysis of PRPD patterns achieved using various measurement methods and different PD source configurations have been investigated. All presented experiments were done under laboratory conditions using PD model sources immersed in the insulation oil. The main purpose of the presented research is to indicate an all-embracing analytical tool that yields an ability to direct comparison (qualitative as well as quantitative) of the AE measurement results with other commonly applied PD measurement methods. The presented results give a solid fundamental for further research work concerning a direct correlation method for AE and other described in the paper diagnostic techniques, mainly in order to continue PD phenomena analysis and assessment in real life high voltage apparatus insulation systems under normal onsite operation conditions. Partial discharge ; Acoustic emission ; Acoustics ; Voltage ; Materials science ; High voltage ; Phase (matter) ; Computer science ; Insulation system ; Electronic engineering ; Electrical engineering ; Physics ; Engineering High voltage insulation and dielectric phenomena ; Power Transformer Diagnostics and Insulation ; Electrical Fault Detection and Protection
Authors: Tianhe Huang | Qianqian Zhao | Yan Su | Defang Ouyang
Source: Asian Journal of Pharmaceutical Sciences (article, 2018-12-08)
Field: Materials Science — Materials Chemistry

Investigation of molecular aggregation mechanism of glipizide/cyclodextrin complexation by combined experimental and molecular modeling approaches Cyclodextrin complexation is a wise strategy to enhance aqueous solubility of water-insoluble drugs. However, the aggregation mechanism of drug-cyclodextrin complexes is still unclear. This research aimed to investigate the molecular aggregation mechanism of glipizide/cyclodextrin complexation by the combination of experimental and modeling methods. Binding free energies between glipizide and cyclodextrins from modeling calculations were higher than those by the phase solubility diagram method. Both experimental and modeling results showed that methylated-β-cyclodextrin exhibited the best solubilizing capability to glipizide. Size-measurement results confirmed the aggregation between glipizide and all four cyclodextrins in high concentrations. Glipizide/γ-cyclodextrin and glipizide/β-cyclodextrin complexes showed stronger aggregation trend than HP-β-cyclodextrin and methylated-β-cyclodextrin. The substituted groups in the rim of HP-β-cyclodextrin and methylated-β-cyclodextrin lead to weak aggregation. This research provided us a clear molecular mechanism of glipizide/cyclodextrin complexation and aggregation. This research will also benefit the formulation development of cyclodextrin solubilization. Glipizide ; Cyclodextrin ; Chemistry ; Solubility ; Solubilization ; Combinatorial chemistry ; Molecular model ; Beta-Cyclodextrins ; Chromatography ; Organic chemistry ; Biochemistry Crystallization and Solubility Studies ; Drug Solubulity and Delivery Systems ; Analytical Chemistry and Chromatography
Authors: Takashi Ito | Govinda Ghimire
Source: ChemElectroChem (article, 2018-07-16)
Field: Materials Science — Materials Chemistry

Electrochemical Applications of Microphase‐Separated Block Copolymer Thin Films Abstract In this review, we discuss electrochemical applications of electrode‐supported thin films derived from microphase‐separated block copolymers (BCPs). In contrast to conventional homopolymers used for electrode modification, BCPs afford periodic nanoscale structures (microdomains) of uniform dimensions (5–100 nm) and predictable morphologies, which can be controlled by adjusting the lengths of individual homopolymer segments. BCPs usable for electrochemical applications consist of two or more segments that form solute‐permeable, redox‐active or etchable microdomains and a chemically inert matrix. The resulting microdomains afford nanoscale molecular/charge transport pathways toward the underlying electrode, whereas the matrix serves as a scaffold to improve film stability in solution. These polymeric thin films provide a unique means for fabricating nanowire arrays via template‐based electrochemical synthesis, designing electrochemical sensors with unique selectivity, and constructing electrochemically‐tunable functional materials. Materials science ; Electrode ; Electrochemistry ; Copolymer ; Nanostructure ; Nanoscopic scale ; Nanotechnology ; Thin film ; Chemical engineering ; Nanowire ; Polymer ; Composite material ; Chemistry Block Copolymer Self-Assembly ; Advanced Polymer Synthesis and Characterization ; Conducting polymers and applications
Authors: Snædís Björgvinsdóttir | Brennan J. Walder | Arthur C. Pinon | Jayasubba Reddy Yarava | Lyndon Emsley
Source: Journal of Magnetic Resonance (article, 2018-01-31)
Field: Chemistry — Spectroscopy

DNP enhanced NMR with flip-back recovery DNP methods can provide significant sensitivity enhancements in magic angle spinning solid-state NMR, but in systems with long polarization build up times long recycling periods are required to optimize sensitivity. We show how the sensitivity of such experiments can be improved by the classic flip-back method to recover bulk proton magnetization following continuous wave proton heteronuclear decoupling. Experiments were performed on formulations with characteristic build-up times spanning two orders of magnitude: a bulk BDPA radical doped o-terphenyl glass and microcrystalline samples of theophylline, l-histidine monohydrochloride monohydrate, and salicylic acid impregnated by incipient wetness. For these systems, addition of flip-back is simple, improves the sensitivity beyond that provided by modern heteronuclear decoupling methods such as SPINAL-64, and provides optimal sensitivity at shorter recycle delays. We show how to acquire DNP enhanced 2D refocused CP-INADEQUATE spectra with flip-back recovery, and demonstrate that the flip-back recovery method is particularly useful in rapid recycling regimes. We also report Overhauser effect DNP enhancements of over 70 at 592.6 GHz/900 MHz. Heteronuclear molecule ; Materials science ; Flip angle ; Decoupling (probability) ; Microcrystalline ; Sensitivity (control systems) ; Solid-state nuclear magnetic resonance ; Spectral line ; Analytical Chemistry (journal) ; Chemistry ; Nuclear magnetic resonance ; Nuclear magnetic resonance spectroscopy ; Physics ; Electronic engineering ; Chromatography ; Crystallography ; Magnetic resonance imaging Advanced NMR Techniques and Applications ; Solid-state spectroscopy and crystallography ; Advanced Battery Materials and Technologies
Authors: Jing Yang | Hua-wen Zhao | Jian He | Cheng‐Pan Zhang
Source: Catalysts (article, 2018-01-14)
Field: Chemistry — Organic Chemistry

Pd-Catalyzed Mizoroki-Heck Reactions Using Fluorine-Containing Agents as the Cross-Coupling Partners The Mizoroki-Heck reaction represents one of the most convenient methods for carbon-carbon double bond formation in the synthesis of small organic molecules, natural products, pharmaceuticals, agrochemicals, and functional materials. Fluorine-containing organic compounds have found wide applications in the research areas of materials and life sciences over the past several decades. The incorporation of fluorine-containing segments into the target molecules by the Mizoroki-Heck reactions is highly attractive, as these reactions efficiently construct carbon-carbon double bonds bearing fluorinated functional groups by simple procedures. This review summarizes the palladium-catalyzed Mizoroki-Heck reactions using various fluorine-containing reagents as the cross-coupling partners. The first part of the review describes the Pd-catalyzed Mizoroki-Heck reactions of aryl halides or pseudo-halides with the fluorinated alkenes, and the second part discusses the Pd-catalyzed Mizoroki-Heck reactions of the fluorinated halides or pseudo-halides with alkenes. Variants of the Pd-catalyzed Mizoroki-Heck reactions with fluorine-containing reagents are also briefly depicted. This work supplies an overview, as well as a guide, to both younger and more established researchers in order to attract more attention and contributions in the realm of Mizoroki-Heck reactions with fluorine-containing participants. Chemistry ; Halide ; Heck reaction ; Reagent ; Aryl ; Catalysis ; Organic chemistry ; Organic synthesis ; Combinatorial chemistry ; Fluorine ; Palladium ; Alkyl Catalytic Cross-Coupling Reactions ; Catalytic C–H Functionalization Methods ; Fluorine in Organic Chemistry
Authors: Simone Zanotto | Giacomo Mazzamuto | Francesco Riboli | G. Biasiol | G. C. La Rocca | Alessandro Tredicucci | Alessandro Pitanti
Source: Nanophotonics (article, 2018-06-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Photonic bands, superchirality, and inverse design of a chiral minimal metasurface Abstract Photonic band structures are a typical fingerprint of periodic optical structures, and are usually observed in spectroscopic quantities such as transmission, reflection, and absorption. Here we show that the chiro‐optical response of a metasurface constituted by a lattice of non‐centrosymmetric, L‐shaped holes in a dielectric slab shows a band structure, where intrinsic and extrinsic chirality effects are clearly recognized and connected to localized and delocalized resonances. Superchiral near‐fields can be excited in correspondence to these resonances, and anomalous behaviors as a function of the incidence polarization occur. Moreover, we have introduced a singular value decomposition (SVD) approach to show that the above mentioned effects are connected to specific fingerprints of the SVD spectra. Finally, by means of an inverse design technique we have demonstrated that the metasurface based on an L‐shaped hole array is a minimal one. Indeed, its unit cell geometry depends on the smallest number of parameters needed to implement arbitrary transmission matrices compliant with the general symmetries for 2d‐chiral structures. These observations enable more powerful wave operations in a lossless photonic environment. Photonic crystal ; Delocalized electron ; Inverse ; Photonics ; Physics ; Chirality (physics) ; Polarization (electrochemistry) ; Lattice (music) ; Singular value decomposition ; Topology (electrical circuits) ; Optics ; Quantum mechanics ; Geometry ; Mathematics ; Chemistry ; Chiral symmetry Metamaterials and Metasurfaces Applications ; Advanced Antenna and Metasurface Technologies ; Photonic Crystals and Applications
Authors: Quanli Ke | Tianjun Sun | Xiaoli Wei | Ya Guo | Shutao Xu | Shudong Wang
Source: Chemical Engineering Journal (article, 2018-11-13)
Field: Chemistry — Inorganic Chemistry

Economical synthesis strategy of RHO zeolites with fine-tuned composition and porosity for enhanced trace CO2 capture Chemistry ; Zeolite ; Monomer ; Adsorption ; Porosity ; Selectivity ; Alkali metal ; Crown ether ; Template ; Chemical engineering ; Ether ; Dimer ; Catalysis ; Inorganic chemistry ; Polymer ; Organic chemistry ; Ion ; Nanotechnology ; Materials science Zeolite Catalysis and Synthesis ; Metal-Organic Frameworks: Synthesis and Applications ; Carbon Dioxide Capture Technologies
Authors: Yoshitaka Hamashima | Yuji Kawato
Source: Synlett (article, 2018-05-14)
Field: Chemistry — Inorganic Chemistry

Enantioselective Bromocyclization of Allylic Amides Mediated by Phosphorus Catalysis Halocyclization of alkenes is commonly employed to increase molecular complexity during organic synthesis because it enables double installation of heteroatoms on a carbon–carbon double bond. Moreover, stereodefined halogenated compounds are widely found among naturally occurring compounds and can serve as versatile chiral building blocks. Therefore, the development of asymmetric halocyclization reactions is of great interest and, in recent years, there has been remarkable progress in catalytic asymmetric halogenation reactions. This account summarizes recent progress made by our group on phosphorus-­catalyzed enantioselective bromocyclization of allylic amides. Building on a comprehensive study of the reaction mechanism, we discovered an intriguing catalytic reaction in which P+Br species serves as a fine-tuning element for substrate fixation. We also describe the application of this bromocyclization to asymmetric desymmetrization of 1,4-diene substrates and a concise synthesis of the HIV-protease inhibitor ­nelfinavir using the newly developed desymmetrization reaction as a key step. 1 Introduction 2 Enantioselective Bromocyclization of Allylic Amides with a BINAP Catalyst 2.1 Bromocyclization with a P/P Catalyst 2.2 Bromocyclization with a P/P=O Catalyst 3 Desymmetrization of Bisallylic Amides through Enantioselective Bromocyclization 3.1 Desymmetrization of Bisallylic Amides 3.2 Enantioselective Synthesis of Nelfinavir 4 Summary Enantioselective synthesis ; Desymmetrization ; Chemistry ; Allylic rearrangement ; Catalysis ; Organic chemistry ; Combinatorial chemistry ; Stereochemistry Vanadium and Halogenation Chemistry ; Asymmetric Synthesis and Catalysis ; Catalytic C–H Functionalization Methods