jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: M. Siddiq
Source: arXiv (Cornell University) (article, 2019-10-02)
Field: Materials Science — Materials Chemistry

Deformation and failure in nanomaterials via a data driven modelling\n approach A data driven computational model that accounts for more than two material\nstates has been presented in this work. Presented model can account for\nmultiple state variables, such as stresses, strains, strain rates and failure\nstress, as compared to previously reported models with two states. Model is\nused to perform deformation and failure simulations of carbon nanotubes and\ncarbon nanotube/epoxy nanocomposites. The model capability of capturing the\nstrain rate dependent deformation and failure has been demonstrated through\npredictions against uniaxial test data taken from literature. The predicted\nresults show a good agreement between data set taken from literature and\nsimulations.\n Materials science ; Deformation (meteorology) ; Carbon nanotube ; Computational model ; Work (physics) ; Strain rate ; Nanomaterials ; Experimental data ; Structural engineering ; Strain (injury) ; Composite material ; Nanotechnology ; Computer science ; Mechanical engineering ; Engineering ; Mathematics ; Simulation Carbon Nanotubes in Composites ; Smart Materials for Construction ; Mechanical Behavior of Composites
Authors: Franco Doro | Niels Akeroyd | Franc Schiet | Anubhav P. S. Narula
Source: Angewandte Chemie (article, 2019-02-07)
Field: Chemistry — Organic Chemistry

The Prins Reaction in the Fragrance Industry: 100th Anniversary (1919–2019) Abstract The Prins reaction, an acid‐catalyzed condensation of alkenes with aldehydes, is used extensively in the fragrance industry. This year we celebrate the 100th anniversary of the discovery of this reaction. In honor of this occasion we present an overview of the diverse applications of the Prins reaction in the synthesis of flavor and fragrance ingredients. To pay tribute to the inventor of the Prins reaction, Hendrik Jacobus Prins, we also provide some insight into his life, scientific, and entrepreneurial accomplishments. Prins reaction ; Honor ; Chemistry ; Tribute ; Organic chemistry ; Catalysis ; Art history ; Art ; Computer science Asymmetric Synthesis and Catalysis ; Analytical Chemistry and Chromatography ; Chemistry and Chemical Engineering
Authors: Marcel Adorna | Stefan Brodner | Jan Falta | Petr Zlámal | Tomáš Fíla
Source: Acta Polytechnica CTU Proceedings (article, 2019-12-06)
Field: Materials Science — Materials Chemistry

EVALUATION OF HOPKINSON BAR EXPERIMENTS USING MULTIPLE DIGITAL IMAGE CORRELATION SOFTWARE TOOLS Three different tools for Digital Image Correlation (DIC) were used for evaluation of dynamic experiments performed using custom Open Hopkinson Pressure Bar (OHPB) apparatus. High strain-rate measurements were performed on specimens of advanced cellular materials with predefined structure and negative Poisson’s ratio. Low impedance polymethyl methacrylate (PMMA) bars instrumented with foil strain-gauges were used for dynamic loading of the specimens. Experiments were observed using a pair of high-speed cameras for imaging of loading process in sufficient quality. Custom developed evaluation DIC tool implemented in Matlab, open-source Matlab tool (NCorr) and commercial DIC software (ISTRA 4D) were all used for evaluation of image sequences recorded by high-speed cameras. Comparison of results obtained using all three different DIC tools and results of complementary strain-gauge measurement are shown in this paper. Verification of reliability of custom made DIC software tool is presented. Digital image correlation ; Split-Hopkinson pressure bar ; MATLAB ; Software ; Bar (unit) ; Strain gauge ; Materials science ; Computer science ; Digital image ; Polymethyl methacrylate ; Image processing ; Image (mathematics) ; Artificial intelligence ; Strain rate ; Composite material ; Physics High-Velocity Impact and Material Behavior ; Advanced Measurement and Detection Methods ; Optical measurement and interference techniques
Authors: Sen Yao | Hunter Moseley
Source: Molecules (article, 2019-09-01)
Field: Chemistry — Spectroscopy

Finding High-Quality Metal Ion-Centric Regions Across the Worldwide Protein Data Bank As the number of macromolecular structures in the worldwide Protein Data Bank (wwPDB) continues to grow rapidly, more attention is being paid to the quality of its data, especially for use in aggregated structural and dynamics analyses. In this study, we systematically analyzed 3.5 Å regions around all metal ions across all PDB entries with supporting electron density maps available from the PDB in Europe. All resulting metal ion-centric regions were evaluated with respect to four quality-control criteria involving electron density resolution, atom occupancy, symmetry atom exclusion, and regional electron density discrepancy. The resulting list of metal binding sites passing all four criteria possess high regional structural quality and should be beneficial to a wide variety of downstream analyses. This study demonstrates an approach for the pan-PDB evaluation of metal binding site structural quality with respect to underlying X-ray crystallographic experimental data represented in the available electron density maps of proteins. For non-crystallographers in particular, we hope to change the focus and discussion of structural quality from a global evaluation to a regional evaluation, since all structural entries in the wwPDB appear to have both regions of high and low structural quality. Protein Data Bank ; Protein Data Bank (RCSB PDB) ; Structural bioinformatics ; Quality (philosophy) ; Electron density ; Atom (system on chip) ; Crystallography ; Ion ; Chemistry ; Chemical physics ; Data mining ; Protein structure ; Physics ; Computer science ; Electron ; Biochemistry Mass Spectrometry Techniques and Applications ; Enzyme Structure and Function ; Protein Structure and Dynamics
Authors: Lili Niu | Matthias Mann
Source: EuPA Open Proteomics (article, 2019-03-01)
Field: Chemistry — Spectroscopy

Quick and clean: Cracking sentences encoded in E. coli by LC–MS/MS, de novo sequencing, and dictionary search In this study, we faced the challenge of deciphering a protein that has been designed and expressed by <i>E. coli</i> in such a way that the amino acid sequence encodes two concatenated English sentences. The letters 'O' and 'U' in the sentence are both replaced by 'K' in the protein. The sequence cannot be found online and carried to-be-discovered modifications. With limited information in hand, to solve the challenge, we developed a workflow consisting of bottom-up proteomics, de novo sequencing and a bioinformatics pipeline for data processing and searching for frequently appearing words. We assembled a complete first question: "Have you ever wondered what the most fundamental limitations in life are?" and validated the result by sequence database search against a customized FASTA file. We also searched the spectra against an <i>E. coli</i> proteome database and found close to 600 endogenous, co-purified <i>E. coli</i> proteins and contaminants introduced during sample handling, which made the inference of the sentence very challenging. We conclude that <i>E. coli</i> can express English sentences, and that de novo sequencing combined with clever sequence database search strategies is a promising tool for the identification of uncharacterized proteins. Proteome ; Sequence database ; Pipeline (software) ; Sequence (biology) ; Workflow ; Computer science ; Protein sequencing ; Sentence ; Computational biology ; Database search engine ; Biology ; Database ; Peptide sequence ; Natural language processing ; Information retrieval ; Bioinformatics ; Search engine ; Programming language ; Genetics ; Gene Advanced Proteomics Techniques and Applications ; Genomics and Phylogenetic Studies ; Machine Learning in Bioinformatics
Authors: Maria Cristina Buta | Ana Maria Toader | Bogdan Frecuş | Corneliu I. Oprea | Fanica Cimpoesu | Gabriela Ioniță
Source: International Journal of Molecular Sciences (article, 2019-09-24)
Field: Chemistry — Physical and Theoretical Chemistry

Molecular and Supramolecular Interactions in Systems with Nitroxide-Based Radicals Nitroxide-based radicals, having the advantage of firm chemical stability, are usable as probes in the detection of nanoscale details in the chemical environment of various multi-component systems, based on subtle variations in their electron paramagnetic resonance spectra. We propose a systematic walk through the vast area of problems and inquires that are implied by the rationalization of solvent effects on the spectral parameters, by first-principle methods of structural chemistry. Our approach consists of using state-of-the-art procedures, like Density Functional Theory (DFT), on properly designed systems, kept at the border of idealization and chemical realism. Thus, we investigate the case of real solvent molecules intervening in different configurations between two radical molecules, in comparison with radicals taken in vacuum or having the solvent that is treated by surrogate models, such as polarization continuum approximation. In this work, we selected the dichloromethane as solvent and the prototype radicals abbreviated TEMPO ((2,2,6,6-Tetramethylpiperidin-1-yl) oxyl). In another branch of the work, we check the interaction of radicals with large toroidal molecules, β-cyclodextrin, and cucurbit[6]uril, modeling the interaction energy profile at encapsulation. The drawn synoptic view offers valuable rationales for understanding spectroscopy and energetics of nitroxide radicals in various environments, which are specific to soft chemistry. Radical ; Chemistry ; Nitroxide mediated radical polymerization ; Supramolecular chemistry ; Molecule ; Density functional theory ; Biomolecule ; Chemical physics ; Computational chemistry ; Photochemistry ; Organic chemistry ; Polymer Photochemistry and Electron Transfer Studies ; Electron Spin Resonance Studies ; Magnetism in coordination complexes
Authors: Yi Ye | Han Qin | Ming Tian | Jianguo Mi
Source: Chinese Journal of Polymer Science (article, 2019-03-12)
Field: Materials Science — Materials Chemistry

Diffusion Mode Transition between Gaussian and Non-Gaussian of Nanoparticles in Polymer Solutions Gaussian ; Diffusion ; Polymer ; Particle (ecology) ; Materials science ; Anomalous diffusion ; Nanoparticle ; Chemical physics ; Statistical physics ; Diffusion process ; Thermodynamics ; Nanotechnology ; Physics ; Chemistry ; Computational chemistry ; Composite material ; Computer science Material Dynamics and Properties ; Nanopore and Nanochannel Transport Studies ; Phase Equilibria and Thermodynamics
Authors: Anastassios Skarlatos | A. Martínez-de-Guerenu | Roberto Miorelli | Aitor Lasaosa | Christophe Reboud
Source: Physica B Condensed Matter (article, 2019-12-16)
Field: Materials Science — Electronic, Optical and Magnetic Materials

A regressor-based hysteresis formulation for the magnetic characterisation of low carbon steels Isothermal process ; Annealing (glass) ; Hysteresis ; Materials science ; Parametric statistics ; Preisach model of hysteresis ; Magnetic hysteresis ; Metallurgy ; Thermodynamics ; Applied mathematics ; Mathematics ; Magnetization ; Physics ; Condensed matter physics ; Statistics ; Magnetic field Magnetic Properties and Applications ; Microstructure and Mechanical Properties of Steels ; Non-Destructive Testing Techniques
Authors: Ruby Hanson
Source: International Journal for Infonomics (article, 2019-12-30)
Field: Chemistry — Physical and Theoretical Chemistry

The Impact of Two-tier Instruments on Undergraduate Chemistry Teacher Trainees: An Illuminative Assessment Research has it that diagnostic tools lead to better teaching and learning strategies as teachers are able to unearth students' deep-seated learning challenges. An illuminative assessment approach was therefore employed to assess how two-tier diagnostic assessments that are alleged to possess inherent capacities to diagnose students' learning difficulties impacted on Ghanaian undergraduate teacher trainees. The obtained results were interpreted within an epistemological framework. Findings indicated that two-tier diagnostic instruments, were effective in revealing learners' conceptual misunderstandings in inorganic chemistry. As many as 43 alternative conceptions were uncovered through the use of diagnostic assessments. These findings would give chemistry teachers an insight into some students' nave conceptions and add up to existing knowledge about students' learning difficulties as well as how teachers can recognise them. Mathematics education ; Medical education ; Engineering physics ; Psychology ; Engineering ; Medicine Various Chemistry Research Topics ; Innovative Teaching Methods ; Science Education and Pedagogy
Authors: Robby Christian | Youho Lee | Hyun Gook Kang
Source: Nuclear Engineering and Design (article, 2019-08-21)
Field: Materials Science — Materials Chemistry

Emergency core cooling system performance criteria for Multi-Layered Silicon Carbide nuclear fuel cladding Cladding (metalworking) ; Silicon carbide ; Nuclear engineering ; Materials science ; Brittleness ; Nuclear reactor core ; Nuclear fuel ; Forensic engineering ; Composite material ; Engineering Nuclear Materials and Properties ; Nuclear reactor physics and engineering ; Nuclear and radioactivity studies
Authors: Jiyong Shi | Xuetao Hu | Xiaobo Zou | Zhiming Guo | Melvin Holmes | Haroon Elrasheid Tahir | Xiaowei Huang | Zhihua Li
Source: Journal of Near Infrared Spectroscopy (article, 2019-05-22)
Field: Chemistry — Analytical Chemistry

Rapid identification of <i>Lactobacillus</i> species using near infrared spectral features of bacterial colonies The feasibility of rapid identification of Lactobacillus species using near-infrared spectral features coupled with chemometrics was investigated. First, bacterial colonies of 11 Lactobacillus strains covering four species ( Lactobacillus casei, Lactobacillus reuteri, Lactobacillus brevis, and Lactobacillus fermentum) were cultured using the spread-plate technique. Near-infrared spectra data of the Lactobacillus species were collected directly from the bacterial colonies. Second, 10 wavenumbers were selected from the near-infrared spectra data using uninformative variables elimination and genetic algorithm, and calibration models based on the 10 selected wavenumbers were built using least squares support vector machine. The identification rates for the prediction set and validation set were 89.04 and 85%, respectively. Third, chemical groups of the Lactobacillus cells contributing to the identification of the Lactobacillus strains were identified using mid infrared. The results of mid infrared data analysis indicated that 9 chemical groups could be considered characteristics for categorizing the 11 Lactobacillus strains. The relationship between the 10 selected wavenumbers and identified chemical groups was identified, which supported the satisfactory performance of the least squares support vector machine calibration model. This study demonstrated that near-infrared spectral features of bacterial colonies could be used for Lactobacillus typing at the strain level. Lactobacillus fermentum ; Lactobacillus reuteri ; Lactobacillus casei ; Lactobacillus ; Partial least squares regression ; Chemometrics ; Biology ; Lactobacillus brevis ; Microbiology ; Chemistry ; Food science ; Mathematics ; Bacteria ; Fermentation ; Lactic acid ; Chromatography ; Statistics ; Genetics Spectroscopy and Chemometric Analyses ; Advanced Chemical Sensor Technologies ; Spectroscopy Techniques in Biomedical and Chemical Research
Authors: Filipe Augusto de Jesus | Barbara Vasconcelos Santana | Giordano Frederico da Cunha Bispo | Cícero Inácio da Silva Filho | Severino Alves | Mário E.G. Valério | José Maurício A. Caiut | Víctor Hugo Vitorino Sarmento
Source: Polymer (article, 2019-09-05)
Field: Materials Science — Materials Chemistry

Fine tuning of polymer content for enhanced structure and luminescent properties of Eu3+:siloxane–poly(methyl methacrylate) hybrids to be applied in photonics Siloxane ; Materials science ; Luminescence ; Polymer ; Dopant ; Methyl methacrylate ; Hybrid material ; Chemical engineering ; Quenching (fluorescence) ; Poly(methyl methacrylate) ; Methacrylate ; Dispersion (optics) ; Polymer chemistry ; Copolymer ; Composite material ; Nanotechnology ; Doping ; Optoelectronics ; Fluorescence Lanthanide and Transition Metal Complexes ; Luminescence Properties of Advanced Materials ; Radioactive element chemistry and processing
Authors: Dongfeng Dang | Donghong Yu | Ergang Wang
Source: Advanced Materials (article, 2019-05-01)
Field: Materials Science — Polymers and Plastics

Conjugated Polymers: Conjugated Donor–Acceptor Terpolymers Toward High‐Efficiency Polymer Solar Cells (Adv. Mater. 22/2019) In article number 1807019, Ergang Wang and co-workers review the recent progress of conjugated donor–acceptor (D–A) terpolymers for efficient polymer solar cells. Compared to D–A alternating copolymers, such terpolymers can give a facile method to not only improve their light absorption, but also fine-tune their energy levels and interchain packing synergistically. Thereby, they highlight the great potential of terpolymers for efficient polymer solar cells. Materials science ; Conjugated system ; Polymer ; Copolymer ; Acceptor ; Polymer solar cell ; Polymer chemistry ; Composite material Conducting polymers and applications ; Organic Electronics and Photovoltaics
Authors: Stefan Mahn | Erhard Kemnitz
Source: Journal of Applied Polymer Science (article, 2019-04-29)
Field: Materials Science — Biomaterials

Modification of low‐molecular polylactic acid by CaF<sub>2</sub> nanoparticles: A new approach to change its material properties ABSTRACT Due to environmental problems and the increasing waste of resources, sustainable biodegradable plastics has become a great topic worldwide. In this communique, we present a simple low‐cost synthesis to improve one of these typically used materials, PLA (polylactic acid). CaF 2 nanoparticles synthesized according the fluorolytic sol–gel synthesis in lactic acid give access to fine tune the material characteristics of LMPLA (low‐molecular polylactic acid) due to a simply to apply polycondensation reaction of lactic acid monomers. Thus, for the first time, homo dispersed CaF 2 up to 15 wt % in PLA is synthesized as cubic nanomaterial improving the characteristics of a subsequently formed thermoplastic in comparison with a polycondensed PLA reference material. A detailed characterization of the synthesized material is provided by using X‐ray imaging, TEM, 19 F MAS NMR, (sol) XRD, MALDI‐TOF, and nanoindentation. The results reveal a promising first step of a modification opportunity of LMPLA regarding melting point, elastic modulus, and hardness. This way it is possible to adjust material characteristics in a simple and inexpensive way, which might broaden the field of possible applications and make biodegradable plastics a more competitive alternative to conventional used ones. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136 , 47875. Polylactic acid ; Materials science ; Thermoplastic ; Condensation polymer ; Lactic acid ; Nanoindentation ; Monomer ; Nanoparticle ; Nanomaterials ; Melting point ; Chemical engineering ; Biodegradable polymer ; Polymer ; Polymer chemistry ; Nanotechnology ; Composite material biodegradable polymer synthesis and properties ; Microplastics and Plastic Pollution ; Recycling and Waste Management Techniques
Authors: Xianxiang Hu | Zhijie Zhang | Yao Lu | Rui Liu | Lei Sun | Ivan P. Parkin | Xia Zhang
Source: Applied Organometallic Chemistry (article, 2019-01-28)
Field: Chemistry — Organic Chemistry

One‐step synthesis of Ag@PS nanospheres via flash nanoprecipitation In the work reported, we utilized a facile flash nanoprecipitation process to generate Ag nanoparticles@nanospheres polymer composites. Ag nanoparticles can be loaded onto the polymeric polystyrene (PS) nanosphere surface using a simple and inexpensive method through in situ growth; the amount of loaded Ag nanoparticles and the size of holes on the PS surface prepared by flash nanoprecipitation can be fine‐tuned by changing the pH of the water medium and the PS nanoparticles should have a greater specific area. The as‐synthesized Ag@PS composite nanoparticles obtained via the one‐step and continuous preparation route show high catalytic activity in the reduction reaction of 4‐nitrophenol. Importantly, the nanoparticles show no loss of catalytic performance over five cycles. Nanoparticle ; Polystyrene ; Flash (photography) ; Chemistry ; Catalysis ; Nanotechnology ; Chemical engineering ; Polymer ; Composite number ; One-Step ; Materials science ; Organic chemistry ; Composite material Nanomaterials for catalytic reactions ; Copper-based nanomaterials and applications ; Advanced Photocatalysis Techniques
Authors: Zhijun Zhang | Woochul Yang
Source: Optical Materials (article, 2019-04-19)
Field: Materials Science — Materials Chemistry

Enhanced quantum efficiency and controllable emissions of Eu through incorporation of Mn2+ in β-NaYF4 nanocrystals Nanocrystal ; Trisodium citrate ; Hydrothermal circulation ; Luminescence ; Doping ; Quantum efficiency ; Materials science ; Hexagonal crystal system ; Nanotechnology ; Chemical engineering ; Emission spectrum ; Chemistry ; Optoelectronics ; Crystallography ; Nuclear chemistry ; Spectral line ; Physics Luminescence Properties of Advanced Materials ; Solid State Laser Technologies ; Perovskite Materials and Applications
Authors: Kun Nie | Xiang Yu | Navnita Kumar | Yihe Zhang
Source: Materials (article, 2019-04-12)
Field: Materials Science — Biomaterials

Versatile Layer-By-Layer Highly Stable Multilayer Films: Study of the Loading and Release of FITC-Labeled Short Peptide in the Drug Delivery Field A viable short FITC-peptide immobilization is the most essential step in the fabrication of multilayer films based on FITC-peptide. These functional multilayer films have potential applications in drug delivery, medical therapy, and so forth. These FITC-peptides films needed to be handled with a lot of care and precision due to their sensitive nature. In this study, a general immobilization method is reported for the purpose of stabilizing various kinds of peptides at the interfacial regions. Utilizing Mesoporous silica nanoparticles can help in the preservation of these FITC-peptides by embedding themselves into these covalently cross-linked multilayers. This basic outlook of the multilayer films is potent enough and could be reused as a positive substrate. The spatio-temporal retention property of peptides can be modulated by varying the number of capping layers. The release speed of guest molecules such as tyrosine within FITC-peptide or/and adamantane (Ad)-in short peptides could also be fine-tuned by the specific arrangements of the multilayers of mesoporous silica nanoparticles (MSNs) and hyaluronic acid- cyclodextrin (HA-CD) multilayer films. Mesoporous silica ; Peptide ; Materials science ; Nanotechnology ; Layer by layer ; Nanoparticle ; Layer (electronics) ; Drug delivery ; Hyaluronic acid ; Substrate (aquarium) ; Fabrication ; Covalent bond ; Combinatorial chemistry ; Mesoporous material ; Chemistry ; Organic chemistry ; Biochemistry Supramolecular Self-Assembly in Materials ; Chemical Synthesis and Analysis ; Dendrimers and Hyperbranched Polymers