jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Jianfeng Huang | Don McGlinchey | Yi Chen | Daniel McMahon
Source: Materials & Design (article, 2020-10-13)
Field: Materials Science — Materials Chemistry

Cross-scale analysis of nickel Superalloy fatigue using Markov state model-molecular dynamics method Molecular dynamics (MD) simulation is an advanced method in microscale modelling of material but it depends on the complexity of the model. The performance of MD simulation is poor once the model size is huge. To accelerate the computing of MD simulation, the Markov state model (MSM) can be applied because of the ability to predict a future state of a stochastic system. With the advantage of MSM and MD applied in material modelling, a good result could be expected where the time scale limitation of MD simulation is bridged by MSM method. In this research, an MSM method based on the MD microstates in which a nickel superalloy's atomic model arrangements and their microstructure evolution have been treated with the Markov properties is presented. This MSM is based and classified by a dislocation model which is a fundamental of the microstructural tessellation evolution. The results indicate that the microstructure evolution in a situation of energy minimisation favours the formation of new faults alongside existing ones. And dislocation accumulation on the grain boundary was observed during fatigue resolving. Some dislocations formatted and grown in the middle of coarse grain and penetrated through the grain. Superalloy ; Materials science ; Microscale chemistry ; Molecular dynamics ; Microstructure ; Statistical physics ; Dislocation ; Multiscale modeling ; Grain boundary ; Markov chain ; Scale (ratio) ; Nickel ; Metallurgy ; Computer science ; Composite material ; Computational chemistry ; Mathematics ; Physics Microstructure and mechanical properties ; High Temperature Alloys and Creep ; High-Velocity Impact and Material Behavior
Authors: Vladislav Sviatskii | Witold Biały | Kirill Sentyakov | Alexandr Repko | B Bako | P Bozek | M Baranov | V Prajova | T Ivanova | D Novokshonov | A Korshunov | M Beno | M Zvoncan | M Kovac | J Peterka | E Pivarciova | P Pokorn | I Buransky | L Morovic | A Chaus | P Pokorny | E Caplovic | Sitkevich | K Domnina | V Repko | A Elbakian | B Sentyakov | P Boek | I Kuric | K Sentyakov | E Kalentev | S Vclav | A Korshun;Ov | V Tarasov | H Kobeticova | V Sviatskii | K Gerulov | I Wachter | Y Nikitin | L Blinov | M Soldn | M Molenda | M Nemeth | A Nemethova | G Michalconok | E Qazizada | E Pivariov | S Vaclav | A Repko | M Sviatskii | M Soldan | M Straka | P Bindzr | A Kadukov | S Garayev | M Sokolov | V Smirnov | T Vopat | V imna | V Yankov | S Zhang | P Wang | X Fu | T Chung
Source: Acta Montanistica Slovaca (article, 2020-06-14)
Field: Materials Science — General Materials Science

Estimation of Quality Indicators of Ecological Thermoplastic Fiber Materials The article discusses the process of obtaining fibrous material from a thermoplastic by blowing methods, and also provides a method for calculating the average diameter d f and length l f of elementary fibers. According to the presented calculations, the average elementary fibers' diameter value d f depends on the airflow speed from the blow head in the fiber formation zone. The greater the air velocity V , the smaller the diameter of the elementary fibers. The elementary fibers' length lf depends on their diameter d f and variable angle of the blowing head diffuser. The smaller the diameter of the elementary fibers d f and the larger the variable angle , the smaller the length of the elementary fibers. At = 0 degrees, the fiber is obtained, with an increase in the angle , the fiber length becomes fixed. The average elementary fibers' diameter d f varies depending on the speed of the airflow flowing from the blowing head in the fiber formation zone. The greater the air velocity V , the smaller the diameter of the elementary fibers. The discrepancy between the calculating results of the average fiber diameter with their real values does not exceed 13%, which, according to the process complexity, can be considered satisfactory. The elementary fibers' length lf depends on the elementary fibers' diameter d f and a variable angle . The smaller the diameter of the elementary fibers d f and the larger the variable angle , the smaller the length of the elementary fibers. At = 0 deg, the infinite length fiber is obtained, and with an increase in the angle , the fiber length becomes fixed. Quality (philosophy) ; Estimation ; Fiber ; Thermoplastic ; Environmental science ; Ecology ; Materials science ; Composite material ; Engineering ; Biology ; Systems engineering Material Properties and Applications
Authors: Dong Wang | Rui Zhou | Yinghui Wu | Houzhi Cai | Yueqiang Zhang
Source: IEEE Access (article, 2020-01-01)
Field: Materials Science — Surfaces, Coatings and Films

Improving External Quantum Efficiency by Subwavelength Nano Multi-Layered Structures for Optoelectronic Devices Based on thin film optics (TFO) and finite element method (FEM), we have theoretically investigated improving external quantum efficiency (EQE) by anti-reflection (AR) films constructed from subwavelength nano multi-layers (NML) of low and high index materials, where the low and high index materials are MgF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> and Ta <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</sub> , respectively. This kind of NML dielectric structures have the advantages of low-cost and flexible. Three kinds of substrates have been studied here, which are glass, polyethylene naphthalate (PEN), and polyethylene terephthalate (PET), respectively. TFO theory has been used to obtain the transmittance and reflectance, which agrees well with FEM results. For NML structure, TFO is more efficient than FEM in terms of calculation time and accuracy. The average AR effects (AAREs) are about 3.69%, 3.46% and 3.07% on glass substrate, about 6.15%, 5.56% and 5.02% on PEN substrate, and about 5.06%, 4.62% and 4.17% on PET substrate, for AR bands (ARBs) 350~800 nm, 350~1100 nm and 350~1500 nm, respectively. The results also reflect that wider AR bandwidth needs more NML layers. In practice, this kind of AR films can be widely applicable to enhance the EQE of the optoelectronic devices (OEDs). Polyethylene naphthalate ; Dielectric ; Quantum efficiency ; Substrate (aquarium) ; Transmittance ; Polyethylene terephthalate ; Materials science ; Optoelectronics ; Composite material Optical Coatings and Gratings ; Photonic and Optical Devices ; GaN-based semiconductor devices and materials
Authors: G. Caron | Thomas Henneron | F. Piriou | Pierre Faverolle | J. C. Mipo
Source: IEEE Transactions on Magnetics (article, 2020-01-09)
Field: Materials Science — Electronic, Optical and Magnetic Materials

3-D Numerical Modeling of Claw-Pole Alternators With its Electrical Environment This article describes a methodology for modeling a six-phase claw-pole alternator with its electrical environment. Magnetic nonlinearities, eddy currents, and rectifiers are taken into account. To solve magnetodynamic problems, we use the modified magnetic vector potential formulation. The complex structure of the machine requires a 3-D finite-element analysis. To limit the mesh size, we introduced a refinement strategy based on the calculation of the time derivative of the magnetic vector potential, a solution to the magnetostatic case. In addition, we propose to reduce the transient state by improving the initial solution from the solution of a magnetostatic problem. These different numerical techniques drastically reduce the computational time and memory resources. To validate the proposed approach, some results are compared with experimental ones. Alternator ; Magnetic potential ; Finite element method ; Eddy current ; Transient (computer programming) ; Vector potential ; Computer science ; Control theory (sociology) ; Topology (electrical circuits) ; Applied mathematics ; Magnetic field ; Mathematics ; Physics ; Engineering ; Electrical engineering ; Power (physics) Magnetic Properties and Applications ; Electromagnetic Simulation and Numerical Methods ; Electric Motor Design and Analysis
Authors: Fengbo Zhou | Zhu Hongqi | Changgeng Li
Source: IEEE Access (article, 2020-01-01)
Field: Chemistry — Analytical Chemistry

Multi-Objective Optimized Overlapping Peak Separation Algorithm for Simultaneous Detection of Copper and Cobalt by Ultraviolet-Visible Spectroscopy In the zinc hydrometallurgy, the excessive impurity ions of copper and cobalt are very harmful to the electrolysis process, which affects product quality and wastes resources. In order to solve the problems of low sensitivity, severe spectral overlap and narrow effective band, an overlapping peak separation algorithm based on multi-objective optimization was proposed for simultaneous detection of copper and cobalt in high concentration zinc solution by ultraviolet-visible spectroscopy. First, according to the characteristics of the spectral signal, the derivative spectroscopy by continuous wavelet transform was used to separate the spectral overlapping peaks of copper and cobalt and shield the zinc interference. Then, taking decomposition scale as decision variable, and the information occupancy and peak separation as the optimization targets, a multi-objective optimization model was established and solved using the particle swarm multi-objective optimization method. Finally, derivative spectroscopy combined with zero-crossing method was used to establish calibration curves for simultaneous detection of copper and cobalt. The experimental results show that the proposed method is suitable for simultaneous detection of trace amounts of copper and cobalt in high concentration zinc solution. Cobalt ; Copper ; Spectroscopy ; Ultraviolet visible spectroscopy ; Zinc ; Materials science ; Analytical Chemistry (journal) ; Algorithm ; Chemistry ; Computer science ; Physics ; Metallurgy ; Chromatography Spectroscopy and Chemometric Analyses ; Advanced Chemical Sensor Technologies ; Water Quality Monitoring and Analysis
Authors: Vyacheslav Kharchenko | M. Yastrebenetsky
Source: Nuclear and Radiation Safety (article, 2020-09-15)
Field: Materials Science — Materials Chemistry

Safety of Nuclear Power Plants and Big Safety in a Time of Covid-19 The paper analyzes challenges caused by Covid-19 pandemic to ensure NPP safety, considers experience accumulated in nuclear energy industry for many years, which may be used in other critical industries in the context of so-called “Big Safety”. The paper provides for measures implemented at Ukrainian NPPs and NPPs of other countries by energy companies in the conditions of Covid-19 to preserve personnel health, which is the main task of ensuring safety. Introducing of the “Big Safety” concept (sometimes called “infrastructure safety”) related to big and complex systems as NPPs is analyzed by analogy with the “Big Data” concept. The study proposes the “Big Safety” concept characterized by systemic, informational and generic aspects. NPP safety is an example of the “Big Safety” since it comprises such aspects. The paper also covers the analysis of “Big Safety” components including functional, informational, physical safety, which are supplemented by infectious safety. It defines possibilities and options of NPP operational experience feedback for other critical systems in the context of “Big Safety”: experience and structure of a powerful system of standards and regulation of their requirements; implementation of modern electronic and information technologies (for example, FPGA) taking into account safety deficits; development and application of advanced systems and tools for monitoring and diagnostics of equipment and various NPP systems; use of independency, diversity and defense in depth principles; implementation of independent verification and validation principle. The paper covers the aspects of the Black Swan effect analyzed on examples of Covid-19 pandemic and Chornobyl NPP accident. The strategies of ensuring strength or mitigating Black Swan consequences are proposed. The recommendations for implementing “Big Safety” concept are formulated. Big data ; Context (archaeology) ; Risk analysis (engineering) ; System safety ; Nuclear power ; Safety standards ; Computer science ; Computer security ; Engineering ; Business ; Reliability engineering Graphite, nuclear technology, radiation studies
Authors: Raphaël La Rocca | Christopher Kune | Mathieu Tiquet | Lachlan Stuart | Theodore Alexandrov | Edwin De Pauw | Loïc Quinton
Source: ChemRxiv (preprint, 2020-09-01)
Field: Chemistry — Spectroscopy

Using Biological Signals for Mass Recalibration of Mass Spectrometry Imaging Data Mass spectrometry imaging (MSI) is a powerful and convenient method to reveal the spatial chemical composition of different biological samples. The molecular annotation of the detected signals is only possible when high mass accuracy is maintained across the entire image and the m/z range. However, the heterogeneous molecular composition of biological samples could result in fluctuations in the detected m/z-values, called mass shift. Mass shifts impact the interpretability of the detected signals by decreasing the number of annotations and by affecting the spatial consistency and accuracy of ion images. The use of internal calibration is known to offer the best solution to avoid, or at least to reduce, mass shifts. The selection of internal calibrating signals for a global MSI acquisition is not trivial, prone to false positive detection of calibrating signals and therefore to poor recalibration. To fill this gap, this work describes an algorithm that recalibrates each spectrum individually by estimating its mass shift with the help of a list of internal calibrating ions generated automatically in a data-adaptive manner. The method exploits RANSAC (Random Sample Consensus) algorithm, to select, in a robust manner, the experimental signal corresponding to internal calibrating signals by filtering out calibration points with infrequent mass errors and by using the remaining points to estimate a linear model of the mass shifts. We applied the method to a zebrafish whole body section acquired at high mass resolution to demonstrate the impact of mass shift on data analysis and the capacity of our algorithm to recalibrate MSI data. We illustrate the broad applicability of the method by recalibrating 31 different public MSI datasets from METASPACE from various samples and types of MSI and show that our recalibration significantly increases the numbers of METASPACE annotations, especially the high-confident annotations at a low false discovery rate. Interpretability ; Mass spectrometry ; Calibration ; Mass spectrometry imaging ; Mass spectrum ; Computer science ; Range (aeronautics) ; Sample (material) ; Biological system ; SIGNAL (programming language) ; Algorithm ; Artificial intelligence ; Pattern recognition (psychology) ; Chemistry ; Mathematics ; Statistics ; Chromatography ; Materials science Mass Spectrometry Techniques and Applications ; Metabolomics and Mass Spectrometry Studies ; Isotope Analysis in Ecology
Authors: Alessandro Bertagnon | Marco Gavanelli | Alessandro Passantino | Guido Sciavicco | Stefano Trevisani
Source: DROPS (Schloss Dagstuhl – Leibniz Center for Informatics) (article, 2020-01-01)
Field: Chemistry — Organic Chemistry

The Horn Fragment of Branching Algebra Branching Algebra is the natural branching-time generalization of Allen’s Interval Algebra. As in the linear case, the consistency problem for Branching Algebra is NP-hard. Being relatively new, however, not much is known about the computational behaviour of the consistency problem of its sub-algebras, except in the case of the recently found subset of convex branching relations, for which the consistency of a network can be tested via path consistency and it is therefore deterministic polynomial. In this paper, following Nebel and Bürckert, we define the Horn fragment of Branching Algebra, and prove that it is a sub-algebra of the latter, being closed under inverse, intersection, and composition, that it strictly contains both the convex fragment of Branching Algebra and the Horn fragment of Interval Algebra, and that its consistency problem can be decided via path consistency. Finally, we experimentally prove that the Horn fragment of Branching Algebra can be used as an heuristic for checking the consistency of a generic network with a considerable improvement over the convex subset. Mathematics ; Branching (polymer chemistry) ; Local consistency ; Algebra representation ; Algebra over a field ; Discrete mathematics ; Combinatorics ; Pure mathematics ; Constraint satisfaction problem Synthetic Organic Chemistry Methods ; Organometallic Complex Synthesis and Catalysis ; Polyoxometalates: Synthesis and Applications
Authors: Vadim Manusov | D. O. Kriukov | Arseniy V. Semenov
Source: International Journal of Power Electronics and Drive Systems/International Journal of Electrical and Computer Engineering (article, 2020-09-18)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Computational and experimental study of air-core HTS transformer electrothermal behaviour at current limiting mode The paper provides the results of the experimental and computational study of the processes occurring in high temperature superconducting transformer windings while secondary winding is short-circuited. The obtained mathematical simulation matches closely with the experimental results. The temperature variation curves for superconducting windings were analysed, and conclusions were made on the necessity of changes in HTS transformer design, namely the necessity of windings heat-insulation from each other and adding a high-resistance coating material for HTS wire in HTS transformer primary winding. Transformer ; Electromagnetic coil ; Materials science ; Limiting ; Energy efficient transformer ; Coating ; Distribution transformer ; Mechanical engineering ; Electrical engineering ; Nuclear engineering ; Composite material ; Voltage ; Engineering Magnetic Properties and Applications ; Physics of Superconductivity and Magnetism ; High-Voltage Power Transmission Systems
Authors: Kobi Felton | Daniel Wigh | Alexei A. Lapkin
Source: ChemRxiv (preprint, 2020-11-19)
Field: Materials Science — Materials Chemistry

Multi-task Bayesian Optimization of Chemical Reactions Recent work has shown how Bayesian optimization (BO) is an efficient method for optimizing expensive experiments such as chemical reactions. However, in previous studies, each optimization has been started from scratch with no information about previous or similar chemical optimization studies. Therefore, BO can still require more iterations than many experimental budgets provide. Here, we overcome this challenge using multi-task BO. Through&lt;i&gt; in silico&lt;/i&gt; benchmarking studies, we show how past experimental data can be leveraged to improve the quality and speed of reaction optimization. Bayesian optimization ; Benchmarking ; Task (project management) ; Computer science ; Bayesian probability ; In silico ; Scratch ; Machine learning ; Artificial intelligence ; Chemistry ; Engineering Machine Learning in Materials Science ; Innovative Microfluidic and Catalytic Techniques Innovation ; Advanced Multi-Objective Optimization Algorithms
Authors: Christine Gräfe | Elena K. Müller | Lennart Gresing | Andreas Weidner | Patricia Radon | Ralf P. Friedrich | Christoph Alexiou | Frank Wiekhorst | Silvio Dutz | Joachim H. Clement
Source: Physical Sciences Reviews (article, 2020-12-04)
Field: Materials Science — Biomaterials

Magnetic hybrid materials interact with biological matrices Abstract Magnetic hybrid materials are a promising group of substances. Their interaction with matrices is challenging with regard to the underlying physical and chemical mechanisms. But thinking matrices as biological membranes or even structured cell layers they become interesting with regard to potential biomedical applications. Therefore, we established in vitro blood-organ barrier models to study the interaction and processing of superparamagnetic iron oxide nanoparticles (SPIONs) with these cellular structures in the presence of a magnetic field gradient. A one-cell-type–based blood-brain barrier model was used to investigate the attachment and uptake mechanisms of differentially charged magnetic hybrid materials. Inhibition of clathrin-dependent endocytosis and F-actin depolymerization led to a dramatic reduction of cellular uptake. Furthermore, the subsequent transportation of SPIONs through the barrier and the ability to detect these particles was of interest. Negatively charged SPIONs could be detected behind the barrier as well as in a reporter cell line. These observations could be confirmed with a two-cell-type–based blood-placenta barrier model. While positively charged SPIONs heavily interact with the apical cell layer, neutrally charged SPIONs showed a retarded interaction behavior. Behind the blood-placenta barrier, negatively charged SPIONs could be clearly detected. Finally, the transfer of the in vitro blood-placenta model in a microfluidic biochip allows the integration of shear stress into the system. Even without particle accumulation in a magnetic field gradient, the negatively charged SPIONs were detectable behind the barrier. In conclusion, in vitro blood-organ barrier models allow the broad investigation of magnetic hybrid materials with regard to biocompatibility, cell interaction, and transfer through cell layers on their way to biomedical application. Biophysics ; Chemistry ; Endocytosis ; Clathrin ; Magnetic nanoparticles ; Iron oxide nanoparticles ; Nanotechnology ; Materials science ; Cell ; Nanoparticle ; Biochemistry ; Biology Nanoparticle-Based Drug Delivery ; Characterization and Applications of Magnetic Nanoparticles ; Barrier Structure and Function Studies
Authors: Khaled Habas | Joan J. Soldevila‐Barreda | Maria Azmanova | Laia Rafols | Anaïs Pitto‐Barry | Diana Anderson | Nicolas P. E. Barry
Source: ChemMedChem (article, 2020-10-29)
Field: Chemistry — Organic Chemistry

Evaluation of the Toxicity of Two Electron‐Deficient Half‐Sandwich Complexes against Human Lymphocytes from Healthy Individuals Abstract Electron‐deficient half‐sandwich complexes are a class of under‐studied organometallics with demonstrated potential as metallodrug candidates. This study investigates the effect of two 16‐electron organoruthenium complexes ([( p‐ cym)Ru(benzene‐1,2‐dithiolato)] ( 1 ) and [( p ‐cym)Ru(maleonitriledithiolate)] ( 2 )) on the cell viability of non‐immortalised human lymphocytes from healthy individuals. The genotoxic effects of 1 and 2 in lymphocytes are also investigated by using the Comet and cytokinesis‐block micronucleus assays. Gene expression studies were carried out on a panel of genes involved in apoptosis and the DNA damage‐repair response. Results show that the two 16‐electron complexes do not have significant effect on the cell viability of human lymphocytes from healthy individuals. However, an increase in DNA damage is induced by both compounds, presumably through oxidative stress production. Toxicity ; Electron ; Chemistry ; Toxicology ; Pharmacology ; Medicine ; Biology ; Internal medicine ; Physics ; Quantum mechanics Free Radicals and Antioxidants ; Carcinogens and Genotoxicity Assessment ; Metal complexes synthesis and properties