jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Matej Kanduč | Won Kyu Kim | Rafael Roa | Joachim Dzubiella
Source: Molecular Systems Design & Engineering (article, 2019-11-05)
Field: Materials Science — Materials Chemistry

Modeling of stimuli-responsive nanoreactors: rational rate control towards the design of colloidal enzymes Responsive polymer-based nanoreactors exhibit complex structure-property-function relationships which require multi-scale modeling and simulation approaches for optimal design and a further development towards 'colloidal enzymes'. Rational design ; Nanoreactor ; Colloid ; Enzyme ; Control (management) Pickering emulsions and particle stabilization ; Hydrogels: synthesis, properties, applications ; Polymer Surface Interaction Studies
Authors: Maura Cesaria | Baldassare Di Bartolo
Source: Nanomaterials (review, 2019-07-22)
Field: Materials Science — Materials Chemistry

Nanophosphors-Based White Light Sources Miniaturization requests and progress in nanofabrication are prompting worldwide interest in nanophosphors as white-emission mercury-free lighting sources. By comparison with their bulk counterparts, nanophosphors exhibit reduced concentration quenching effects and a great potential to enhance luminescence efficiency and tunability. In this paper, the physics of the nanophoshors is overviewed with a focus on the impact of spatial confinement and surface-to-volume ratio on the luminescence issue, as well as rare earth-activated multicolor emission for white light (WL) output. In this respect, the prominently practiced strategies to achieve WL emission are single nanophosphors directly yielding WL by means of co-doping and superposition of the individual red, green, and blue emissions from different nanophosphors. Recently, a new class of efficient broadband WL emitting nanophosphors has been proposed, i.e., nominally un-doped rare earth free oxide (yttrium oxide, Y<sub>2</sub>O<sub>3</sub>) nanopowders and Cr transition metal-doped garnet nanocrystals. In regard to this unconventional WL emission, the main points are: it is strictly a nanoscale phenomenon, the presence of an emitting center may favor WL emission without being necessary for observing it, and, its inherent origin is still unknown. A comparison between such an unconventional WL emission and the existing literature is presented to point out its novelty and superior lighting performances. Luminescence ; Materials science ; Yttrium ; Nanotechnology ; Doping ; Light emission ; Optoelectronics ; Oxide ; Optics ; Physics ; Metallurgy Luminescence Properties of Advanced Materials ; Perovskite Materials and Applications ; Advanced Photocatalysis Techniques
Authors: Christoph Göbel | Christian Hils | Markus Drechsler | Dirk Baabe | Andreas Greiner | Holger Schmalz | Birgit Weber
Source: Angewandte Chemie International Edition (article, 2019-12-31)
Field: Chemistry — Organic Chemistry

Confined Crystallization of Spin‐Crossover Nanoparticles in Block‐Copolymer Micelles Nanoparticles of the spin-crossover coordination polymer [FeL(bipy)]<sub>n</sub> were synthesized by confined crystallization within the core of polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) diblock copolymer micelles. The 4VP units in the micellar core act as coordination sites for the Fe complex. In the bulk material, the spin-crossover nanoparticles in the core are well isolated from each other allowing thermal treatment without disintegration of their structure. During annealing above the glass transition temperature of the PS block, the transition temperature is shifted gradually to higher temperatures from the as-synthesized product (T<sub>1/2</sub> ↓=163 K and T<sub>1/2</sub> ↑=170 K) to the annealed product (T<sub>1/2</sub> ↓=203 K and T<sub>1/2</sub> ↑=217 K) along with an increase in hysteresis width from 6 K to 14 K. Thus, the spin-crossover properties can be shifted towards the properties of the related bulk material. The stability of the nanocomposite allows further processing, such as electrospinning from solution. Copolymer ; Micelle ; Crystallization ; Materials science ; Nanoparticle ; Crossover ; Spin crossover ; Block (permutation group theory) ; Chemical engineering ; Nanotechnology ; Polymer ; Computer science ; Crystallography ; Chemistry ; Physical chemistry ; Engineering ; Mathematics ; Artificial intelligence ; Composite material ; Aqueous solution Nanomaterials for catalytic reactions ; Block Copolymer Self-Assembly ; Magnetism in coordination complexes
Authors: Peng Lü | Álvaro Mayoral | Luis Gómez‐Hortigüela | Yaping Zhang | Miguel Á. Camblor
Source: Chemistry of Materials (article, 2019-07-24)
Field: Chemistry — Inorganic Chemistry

Synthesis of 3D Large-Pore Germanosilicate Zeolites Using Imidazolium-Based Long Dications Introduction of small molar fractions of Ge in a synthesis system otherwise yielding the monodimensional large-pore zeolite MTW produced three 3D large-pore materials as the Ge fraction increased: *BEA, HPM-8, and HPM-7. HPM-8 is a zeolite consisting of an intergrowth of polymorphs D and E of the zeolite Beta family with a large predominance (>80%) of polymorph D, according to DIFFaX simulations and high-resolution scanning transmission electron microscopy analysis. After calcination, HPM-8 becomes remarkably stable upon contact with ambient air. HPM-7 likely possesses the POS topology, which is related to polymorph C. The density of double 4-ring (D4R) units in the crystallized materials increases from *BEA to HPM-8 to HPM-7, that is, as the Ge fraction increases. Interestingly, molecular mechanics show that in both HPM-7 and HPM-8, the organic dications prefer to site with their imidazolium rings in close contact with the D4R units as a consequence of a stronger confinement in this position. Indeed, the structure-directing role of these long dications can be explained as a consequence of the appropriate distance match between adjacent D4R units in both zeolite frameworks (and hence the negative charges associated with the occluded fluoride) and the imidazolium rings of these organic dications (and hence the positive charges), which is dictated by the length of the alkyl spacers, thus driving the crystallization pathway toward these particular germanosilicate zeolites. Zeolite ; Crystallization ; Alkyl ; Crystallography ; Calcination ; Chemistry ; Materials science ; Organic chemistry ; Catalysis Zeolite Catalysis and Synthesis ; Chemical Synthesis and Characterization ; Mesoporous Materials and Catalysis
Authors: Michael Ruppel | Dominik Lungerich | Sabrina Sturm | Rainer Lippert | Frank Hampel | Norbert Jux
Source: Chemistry - A European Journal (article, 2019-12-17)
Field: Materials Science — Materials Chemistry

A Comprehensive Study on Tetraaryltetrabenzoporphyrins Invited for the cover of this issue are the groups of Lungerich and Jux at the Friedrich-Alexander University Erlangen-Nuernberg. The image depicts the synthetic feasibility with a "TATBP tuning shop", which shows the change of the four meso aryl substituents to modify the performance of the molecule. Read the full text of the article at 10.1002/chem.201904718. Nanotechnology ; Context (archaeology) ; Synthon ; Isoindole ; Molecule ; Materials science ; Chemistry ; Computer science ; Combinatorial chemistry ; Biochemical engineering ; Engineering ; Organic chemistry ; Biology Porphyrin and Phthalocyanine Chemistry ; Analytical Chemistry and Sensors ; Luminescence and Fluorescent Materials
Authors: Tomilola J. Ajayi | Moses A. Ollengo | Lukas le Roux | Michael N. Pillay | Richard J. Staples | Shannon M. Biros | Kasper Wenderich | Bastian Mei | Werner E. van Zyl
Source: ChemistrySelect (article, 2019-07-01)
Field: Chemistry — Organic Chemistry

Heterodimetallic Ferrocenyl Dithiophosphonate Complexes of Nickel(II), Zinc(II) and Cadmium(II) as Sensitizers for TiO <sub>2</sub> ‐Based Dye‐Sensitized Solar Cells Abstract The formation, characterization, and dye sensitized solar cell application of nickel(II), zinc(II) and cadmium(II) ferrocenyl dithiophosphonate complexes were investigated. The multidentate monoanionic ligand [S 2 PFc(OH)] − ( L1 ) was synthesized. The reaction between metal salt precursors and L1 produced Ni(II) complexes of the type [Ni{S 2 P(Fc)(OH)} 2 ] ( 1 ) (molar ratio 1:2), and a tetranickel(II) complex of the type [Ni 2 {S 2 OP(Fc)} 2 ] 2 ( 2 ) (molar ratio (1:1). It also produced a Zn(II) complex [Zn{S 2 P(Fc)(OH)} 2 ] 2 ( 3 ), and a Cd(II) complex [Cd{S 2 P(Fc)(OH)} 2 ] 2 ( 4 ). Complexes 1–4 were characterized by 1 H and 31 P NMR, FTIR and elemental analysis, and complexes 1 and 2 were additionally analyzed by X‐ray crystallography. The first examples of dye‐sensitized solar cells (DSSCs) co‐sensitized with ferrocenyl dithiophosphonate complexes 1–4 are reported. Co‐sensitization with the ruthenium dye N719, produced the dye materials ( 3 )‐N719 (η=8.30%) and ( 4 )‐N719 (η=7.78%), and they were found to have a better overall conversion efficiency than the pure Ru N719 dye standard (η=7.14%) under the same experimental conditions. The DSSCs were characterized using UV/vis, cyclic voltammetry, electrochemical impedance spectroscopy (EIS), photovoltaic‐ (I−V curves), and performing incident photon‐to‐current efficiency (IPCE) measurements. Dye-sensitized solar cell ; Nickel ; Chemistry ; Cyclic voltammetry ; Zinc ; Denticity ; Electrochemistry ; Metal ; Ruthenium ; Nuclear chemistry ; Cadmium ; Dielectric spectroscopy ; Inorganic chemistry ; Ligand (biochemistry) ; Physical chemistry ; Catalysis ; Organic chemistry ; Electrode Organometallic Compounds Synthesis and Characterization ; Polyoxometalates: Synthesis and Applications ; Crystal Structures and Properties
Authors: Oscar E. Bonilla-Manrique | Julio E. Posada-Román | José A. García-Souto | Marta Ruiz-Llata
Source: Sensors (article, 2019-06-29)
Field: Chemistry — Spectroscopy

Sub-ppm-Level Ammonia Detection Using Photoacoustic Spectroscopy with an Optical Microphone Based on a Phase Interferometer A sensitive optical microphone for photoacoustic spectroscopy based on the common path topology of a fibre laser Doppler vibrometer (FLDV) using phase-generated carrier demodulation and a slim diaphragm as an acoustic wave transducer was demonstrated. A resonant gas cell was adapted to enhance gas-detection performance and simultaneously provide efficient cancellation of the window background acoustic signal. Ammonia (NH<sub>3</sub>) was selected as the target gas. The absorption line was experimentally identified using a distributed feedback laser diode emitting at 1530 nm. The linearity and sensitivity of the gas sensor were measured using wavelength modulation spectroscopy with second harmonic detection. A Teflon diaphragm was used to implement the optical microphone, along with the FLDV, showing a minimum detectable pressure of 79.5 μPa/Hz<sup>1/2</sup>. The noise-equivalent absorption sensitivity for NH<sub>3</sub> detection at the absorption line at 1531.7 nm was 1.85 × 10<sup>-8</sup> W cm<sup>-1</sup> Hz<sup>-1/2</sup>, and the limit of detection was 785 ppbv. Photoacoustic spectroscopy ; Materials science ; Microphone ; Interferometry ; Optics ; Tunable diode laser absorption spectroscopy ; Absorption (acoustics) ; Laser Doppler vibrometer ; Demodulation ; Spectroscopy ; Sensitivity (control systems) ; Laser ; Transducer ; Absorption spectroscopy ; Wavelength ; Optoelectronics ; Tunable laser ; Acoustics ; Sound pressure ; Distributed feedback laser ; Electronic engineering ; Physics ; Telecommunications Spectroscopy and Laser Applications ; Advanced Chemical Sensor Technologies ; Gas Sensing Nanomaterials and Sensors
Authors: S. Rahimi | T.J. Marrow
Source: Materials & Design (article, 2019-11-27)
Field: Materials Science — Metals and Alloys

A new method for predicting susceptibility of austenitic stainless steels to intergranular stress corrosion cracking Microstructures of type 304 austenitic stainless steel, produced through thermo-mechanical processing, were analysed with large area EBSD and optical image analysis assessments of the attacked grain boundary cluster after DL-EPR testing. The thermo-mechanically processed microstructures were exposed to acidified potassium tetrathionate (K2S4O6) solution under tensile stress and the lengths and distributions of the initiated intergranular crack nuclei were assessed. The crack populations were quantified by fitting a Gumbel extreme value statistics distribution to evaluate their characteristic crack length. A factor (susceptibility parameter) is introduced to rank the degree of susceptibility to intergranular stress corrosion cracking of thermo-mechanically processed microstructures. This accounts for the network connectivity of the sensitised grain boundaries, the grain size and the degree of sensitisation. Similar rankings are obtained for this susceptibility parameter and characteristic crack lengths of the assessed microstructures, in which the thermo-mechanical treatments increased the population of grain boundaries with resistance to stress corrosion cracking. Materials science ; Intergranular corrosion ; Stress corrosion cracking ; Metallurgy ; Microstructure ; Grain boundary ; Electron backscatter diffraction ; Corrosion ; Stress (linguistics) ; Composite material Hydrogen embrittlement and corrosion behaviors in metals ; Microstructure and Mechanical Properties of Steels ; High Temperature Alloys and Creep
Authors: Roman Rousseau | Nicolas Maurin | Wioletta Trzpil | M. Bahriz | A. Vicet
Source: Sensors (article, 2019-12-16)
Field: Chemistry — Spectroscopy

Quartz Tuning Fork Resonance Tracking and application in Quartz Enhanced Photoacoustics Spectroscopy The quartz tuning fork (QTF) is a piezoelectric transducer with a high quality factor that was successfully employed in sensitive applications such as atomic force microscopy or Quartz-Enhanced Photo-Acoustic Spectroscopy (QEPAS). The variability of the environment (temperature, humidity) can lead to a drift of the QTF resonance. In most applications, regular QTF calibration is absolutely essential. Because the requirements vary greatly depending on the field of application, different characterization methods can be found in the literature. We present a review of these methods and compare them in terms of accuracy. Then, we further detail one technique, called Beat Frequency analysis, based on the transient response followed by heterodyning. This method proved to be fast and accurate. Further, we demonstrate the resonance tracking of the QTF while changing the temperature and the humidity. Finally, we integrate this characterization method in our Resonance Tracking (RT) QEPAS sensor and show the significant reduction of the signal drift compared to a conventional QEPAS sensor. Tuning fork ; Photoacoustic spectroscopy ; Tracking (education) ; Materials science ; Transducer ; Resonance (particle physics) ; Quartz ; Characterization (materials science) ; Spectroscopy ; Acoustics ; Optoelectronics ; Electronic engineering ; Nanotechnology ; Vibration ; Engineering ; Physics Spectroscopy and Laser Applications ; Terahertz technology and applications ; Acoustic Wave Resonator Technologies
Authors: Erich-Christian Oerke | Marlene Leucker | Ulrike Steiner
Source: Plant Methods (article, 2019-11-16)
Field: Chemistry — Analytical Chemistry

Sensory assessment of Cercospora beticola sporulation for phenotyping the partial disease resistance of sugar beet genotypes For the first time, hyperspectral imaging was successfully tested for the quantification of sporulation as a fungal activity depending on host plant suitability. The potential of this non-invasive and non-destructive approach for the quantification of fungal sporulation in other host-pathogen systems and for the phenotyping of crop traits complex as sporulation resistance is discussed. Cercospora ; Sugar beet ; Leaf spot ; Biology ; Spore ; Hyperspectral imaging ; Genotype ; Horticulture ; Botany ; Genetics ; Gene Spectroscopy and Chemometric Analyses ; Remote Sensing in Agriculture ; Remote-Sensing Image Classification
Authors: Evangelos I. Gkanas | Christodoulos N. Christodoulou | G. Tzamalis | Emmanuel Stamatakis | A. Chroneos | Konstantinos Deligiannis | George Karagiorgis | A. K. Stubos
Source: Renewable Energy (article, 2019-08-22)
Field: Materials Science — Materials Chemistry

Numerical investigation on the operation and energy demand of a seven-stage metal hydride hydrogen compression system for Hydrogen Refuelling Stations Gas compressor ; Hydrogen ; Compression (physics) ; Hydride ; Hydrogen storage ; Compression ratio ; Work (physics) ; Nuclear engineering ; Thermal ; Materials science ; Environmental science ; Process engineering ; Mechanical engineering ; Thermodynamics ; Engineering ; Chemistry ; Physics ; Composite material Hydrogen Storage and Materials ; Hybrid Renewable Energy Systems ; Spacecraft and Cryogenic Technologies
Authors: P. Drexler | Martin Čáp | Pavel Fiala | Miloslav Steinbauer | R. Kadlec | M. Kaska | Lubomír Kočiš
Source: Sensors (article, 2019-02-22)
Field: Materials Science — Materials Chemistry

A Sensor System for Detecting and Localizing Partial Discharges in Power Transformers with Improved Immunity to Interferences The paper reports on the solution, principles, and application results related to a system for diagnosing main transformers in power plants via the radiofrequency method. The subject of the diagnostics is the occurrence of partial discharge activity in transformers. The technical solution of the system is characterized in the introductory section of the article. There then follows a description of the operating principle and the implemented novel advanced methods for signal detection and source localization. The results obtained from practical application of the system within the diagnostics of high-power transformers are presented as well. Because ambient electromagnetic disturbance was recognized as a major issue during the system development, novel detection methods were proposed, implemented, and verified. The principal approach utilizes an external radiofrequency sensor to detect outer impulse disturbance and to eliminate disturbance-triggered acquisitions, and it also ensures direct real-time visualization of the desired impulse signals. The ability of weak signal detection was verified via artificial impulse signal injection into the transformer. The developed detection methods were completed with localization techniques for signal source estimation. The desired impulse signal was detected and localized during full operation of the main transformer, despite the presence of strong electromagnetic interference. Transformer ; Impulse (physics) ; Computer science ; Electronic engineering ; Partial discharge ; Electromagnetic interference ; Engineering ; Voltage ; Electrical engineering ; Physics High voltage insulation and dielectric phenomena ; Power Transformer Diagnostics and Insulation ; Lightning and Electromagnetic Phenomena
Authors: Takuya Inokuchi | Ryosuke Okamoto | Noriyoshi Arai
Source: Liquid Crystals (article, 2019-08-27)
Field: Materials Science — Materials Chemistry

Predicting molecular ordering in a binary liquid crystal using machine learning Machine learning is a category of AI technology that is utilized in the product development cycle in numerous industries. It was reported that machine learning can be applied to predict the chemical properties of functional materials, for example, the self-assembly of surfactant solutions (Nanoscale, 2018, 10, 16013) and the chemical reactions of copper nanoparticles (ACS Energy Lett., 2018, 3, 2983). A liquid crystal (LC) molecule is a representative functional material. Monodisperse systems have been targeted in many theoretical studies; however, the resulting products usually have a polydisperse distribution. It has been reported in several studies that the properties exhibited by polydisperse systems are different from those observed in monodisperse systems. In this study, we focus on the physical properties of polydisperse systems i.e. the ratio of binary LC molecules on the phase transition temperature and the possibility of predicting the physical properties of the system using machine learning. A relatively high prediction accuracy was obtained using machine learning. This study demonstrates that machine learning can be utilized to predict the phase transition temperature of polydispersed LC systems. The results of this study will contribute to the further development of material science and molecular design via the application of machine learning. Materials science ; Dispersity ; Liquid crystal ; Nanoparticle ; Binary number ; Machine learning ; Artificial intelligence ; Phase transition ; Nanotechnology ; Computer science ; Thermodynamics ; Physics ; Mathematics Block Copolymer Self-Assembly ; Machine Learning in Materials Science ; Advanced Polymer Synthesis and Characterization
Authors: Xinyu Li | Raymond Chiong | Zhongyi Hu | David Cornforth | Alister J. Page
Source: Journal of Chemical Theory and Computation (article, 2019-09-10)
Field: Materials Science — Materials Chemistry

Improved Representations of Heterogeneous Carbon Reforming Catalysis Using Machine Learning Predicting adsorption energies of reaction intermediates is critical for determining catalytic reaction mechanisms. Here, we present three combined representations for predicting adsorption energies of carbon reforming species on transition-metal surfaces. Among the three combined representations, the Elemental Properties and Spectral London Axilrod-Teller-Muto (EP&SLATM) representation, which uses separate EP and SLATM representations for the surface and adsorbates, yields the lowest mean absolute error (MAE) of ∼0.18 eV with respect to density functional theory (DFT) adsorption formation energies for 68 adsorbates on four low-index metal facets (Cu(111), Pt(111), Pd(111), Ru(0001)). All three combined representations also have lower MAEs compared with linear scaling relations. Notably, two of the combined representations achieve their results using empirical/experimental molecular structures only (i.e., without recourse to structural optimization based on first-principles methods such as DFT). The combined representations enable improved efficiency for predicting heterogeneous catalytic mechanisms using machine learning approaches, largely bypassing expensive electronic structure calculations. Further, we show that the combined representations enable "cross-surface" training with regression and tree-based machine learning methods. That is, to predict adsorption formation energies on a particular catalyst metal, these methods only need a small amount of training samples (20%) on that metal. Density functional theory ; Adsorption ; Catalysis ; Representation (politics) ; Carbon fibers ; Hybrid functional ; Chemistry ; Computer science ; Computational chemistry ; Materials science ; Physical chemistry ; Algorithm ; Organic chemistry ; Composite number Machine Learning in Materials Science ; Electrocatalysts for Energy Conversion ; CO2 Reduction Techniques and Catalysts