jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Alisa R. Bogdanova | Dmitry V. Krasnikov | Eldar M. Khabushev | Javier A. Ramirez B. | Albert G. Nasibulin
Source: International Journal of Molecular Sciences (article, 2023-04-03)
Field: Materials Science — Materials Chemistry

Bithiophene as a Sulfur-Based Promotor for the Synthesis of Carbon Nanotubes and Carbon-Carbon Composites We assess bithiophene (C<sub>8</sub>H<sub>6</sub>S<sub>2</sub>) as a novel sulfur-based promotor for the growth of single-walled carbon nanotubes (SWCNTs) in the aerosol (floating catalyst) CVD method. Technologically suitable equilibrium vapor pressure and an excess of hydrocarbon residuals formed under its decomposition make bithiophene an attractive promoter for the production of carbon nanotubes in general and specifically for ferrocene-based SWCNT growth. Indeed, we detect a moderate enhancement in the carbon nanotube yield and a decrease in the equivalent sheet resistance of the films at a low bithiophene content, indicating the improvement of the product properties. Moreover, the relatively high concentrations and low temperature stability of bithiophene result in non-catalytical decomposition, leading to the formation of pyrolytic carbon deposits; the deposits appear as few-layer graphene structures. Thus, bithiophene pyrolysis opens a route for the cheap production of hierarchical composite thin films comprising carbon nanotubes and few-layer graphene, which might be of practical use for hierarchical adsorbents, protective membranes, or electrocatalysis. Carbon nanotube ; Materials science ; Pyrolytic carbon ; Carbon fibers ; Graphene ; Pyrolysis ; Carbide-derived carbon ; Chemical engineering ; Carbonization ; Catalysis ; Sulfur ; Decomposition ; Electrocatalyst ; Nanotechnology ; Composite material ; Composite number ; Carbon nanofiber ; Organic chemistry ; Electrochemistry ; Chemistry ; Electrode ; Scanning electron microscope Carbon Nanotubes in Composites ; Graphene research and applications ; Fullerene Chemistry and Applications
Authors: Pengfei Fu | Lingyun Hou
Source: AIP Advances (article, 2023-07-01)
Field: Chemistry — Spectroscopy

Tomographic measurements of temperature and species concentration via deep learning and wavelength modulated absorption spectroscopy To achieve the 2-D nonintrusive measurements of temperature and species concentration in the combustion field, a new framework, combining calibration-free wavelength modulation absorption spectroscopy (CF-WMS) with a designed convolutional neural network (CNN), was developed. The principle of the CF-WMS, along with the architecture of the CNN net, the training, and the performance of the network, has been investigated. The region of interest was discretized into 24 × 24 pixels2, and 48 probing beams with six targeted frequencies were used to verify the feasibility of the designed CNN with WMS 2f/1f signal for temperature and species concentration reconstruction. 20 000 samples of temperature and water vapor concentration distributions are randomly fabricated, featuring three randomly positioned Gaussian distributions. Reconstructed images of the phantoms agreed well with the original distributions with the relative error of about 5.0%–9.2% and 8.0%–12.4% using 17 000 training datasets with different beam arrangements for temperature and H2O species, respectively. Several representative beam arrangements with a limited number have been examined and compared. The beam arrangement BA2 and BA3 exhibited better performance than BA1 with average errors of about 5% and 8% for temperature and H2O species, respectively. Such a method can provide an effective way to achieve spatially and temporally resolved, real-time, in situ monitoring in practical combustion environments. Absorption (acoustics) ; Combustion ; Convolutional neural network ; Wavelength ; Calibration ; Spectroscopy ; Temperature measurement ; Materials science ; Beam (structure) ; Gaussian beam ; Absorption spectroscopy ; Optics ; Computer science ; Analytical Chemistry (journal) ; Optoelectronics ; Physics ; Artificial intelligence ; Chemistry Spectroscopy and Laser Applications ; Atmospheric and Environmental Gas Dynamics ; Atmospheric Ozone and Climate
Authors: Jinwen Lu | Kaile Ji | Longchao Zhuo | Bingqing Chen | Hui Shao | Wangtu Huo | Yongqing Zhao
Source: Coatings (article, 2023-11-29)
Field: Materials Science — Materials Chemistry

Revealing High-Temperature Oxidation and Tensile Behaviors along with Underlying Mechanisms of a Titanium Alloy with Precipitated Titanium Silicide Titanium alloys, with their impressive strength relative to their weight, resistance to corrosion, and compatibility with biological systems, have found extensive applications in various industries. In high-temperature environments, especially within the aerospace sector, it is essential to advance titanium alloys that boast enhanced resistance to oxidation and superior mechanical characteristics. This work investigates the oxidation characteristics and mechanical performances at high temperatures of a titanium alloy with titanium silicide particles. Oxidation at temperatures of 600–700 °C over a span of 8–32 h led to the formation of protective oxide layers and moderate oxidation rates. However, accelerated oxidation and oxide spallation occurred after exposed at 800 °C for a period of 16 h, indicating inadequate oxidation resistance over 800 °C. Subsequent tensile tests at 650 °C revealed intricate dislocation patterns in the α-Ti matrix and their strong interaction with interfaces of α-Ti/Ti5Si3, which is indicative of an efficient load transfer between the precipitates and the matrix. Overall, this study offers fresh perspectives on the oxidation kinetics and the deformation processes of titanium alloys with in-situ Ti5Si3 particles at high temperatures. These insights will guide subsequent alloy development endeavors aiming to broaden the use of titanium alloys in increasingly challenging high-temperature settings. Materials science ; Titanium ; Alloy ; Corrosion ; Metallurgy ; Silicide ; Oxide ; Titanium alloy ; High-temperature corrosion ; Ultimate tensile strength ; Spallation ; Titanium oxide ; Chemical engineering ; Silicon Titanium Alloys Microstructure and Properties ; Intermetallics and Advanced Alloy Properties ; Nuclear Materials and Properties
Authors: Marcin Gerlich | Marcin Hara | W. A. Trzciński
Source: Materials (article, 2023-05-17)
Field: Materials Science — Polymers and Plastics

Tungsten and Copper (II) Oxide Mixtures as Gasless Time Delay Compositions for Mining Detonators The widespread use of pyrotechnic compositions in time delay detonators is the reason for research aimed at expanding knowledge of the combustion properties of new pyrotechnic mixtures, whose components react with each other in the solid or liquid state. Such a method of combustion would make the rate of combustion independent of the pressure inside the detonator. This paper presents the effect of the parameters of W/CuO mixtures on their properties of combustion. As this composition has not been the subject of previous research and is not described in the literature, the basic parameters, such as the burning rate and the heat of combustion, were determined. In order to determine the reaction mechanism, a thermal analysis was performed, and the combustion products were determined using the XRD technique. Depending on the quantitative composition and density of the mixture, the burning rates were between 4.1-6.0 mm/s and the heat of combustion in the range of 475-835 J/g was measured. The gas-free combustion mode of the chosen mixture was proved using DTA and XRD. Determination of the qualitative composition of the combustion products and the heat of combustion allowed estimation of the adiabatic combustion temperature. Combustion ; Detonator ; Materials science ; Adiabatic process ; Heat of combustion ; Adiabatic flame temperature ; Thermodynamics ; Nuclear engineering ; Chemical engineering ; Analytical Chemistry (journal) ; Chemistry ; Explosive material ; Combustor ; Organic chemistry ; Engineering ; Physics Transition Metal Oxide Nanomaterials ; Energetic Materials and Combustion ; Luminescence Properties of Advanced Materials
Authors: Danyang Zheng | Chenqi Yang | Xiaogang Li | Dong Liu | Yan Wang | Xuesong Wang | Xueying Zhang | Yinfeng Tan | Yu‐Chen Zhang | Youbin Li | Junyu Xu
Source: Molecules (article, 2023-09-13)
Field: Chemistry — Organic Chemistry

Design, Synthesis, Antitumour Evaluation, and In Silico Studies of Pyrazolo-[1,5-c]quinazolinone Derivatives Targeting Potential Cyclin-Dependent Kinases An efficient, straightforward, and metal-free methodology to rapidly access functionalised pyrazolo-[1,5-c]quinazolinones via a [3 + 2] dipolar cycloaddition and regioselective ring expansion process was developed. The synthesised compounds were characterised by methods such as NMR, HRMS, and HPLC. The in vitro antiproliferative activity against A549 cells (non-small cell lung cancer) was significant for compounds 4i, 4m, and 4n with IC<sub>50</sub> values of 17.0, 14.2, and 18.1 μM, respectively. In particular, compounds 4t and 4n showed inhibitory activity against CDK9/2. Predicted biological target and molecular modelling studies suggest that the compound 4t may target CDKs for antitumour effects. The synthesised derivatives were considered to have moderate drug-likeness and sufficient safety in silico. In summary, a series of pyrazolo-[1,5-c]quinazolinone derivatives with antitumour activity is reported for the first time. We provide not only a simple and efficient synthetic method but also helpful lead compounds for the further development of novel cyclin-dependent kinase (CDK) inhibitors. Quinazolinone ; Cyclin-dependent kinase ; In silico ; Chemistry ; Cycloaddition ; Kinase ; Combinatorial chemistry ; Pharmacophore ; Regioselectivity ; In vitro ; Stereochemistry ; Biochemistry ; Cell cycle ; Cell Quinazolinone synthesis and applications ; Synthesis and Characterization of Heterocyclic Compounds ; Synthesis and Biological Evaluation
Authors: Grayson Schaer | Timothy Bretl
Source: Advanced Theory and Simulations (article, 2023-05-10)
Field: Chemistry — Organic Chemistry

Closed‐Loop Control of Front Speed During Frontal Polymerization of Dicyclopentadiene—A Numerical Study Abstract The application of closed‐loop control to enforce a target front speed during frontal polymerization (FP) of dicyclopentadiene under various initial and boundary conditions is demonstrated. Uncontrolled propagation of FP reactions can result in frontal quenching due to heat loss, unstable front propagation, material overheating, spontaneous pattern formation, and heterogenous cured material properties. These disadvantageous properties of FP limit its use to cases with highly controlled initial and boundary conditions. It is shown with results in simulation that these problems can be mitigated in three ways through the application of closed‐loop control. First, it is shown that a target front speed can be enforced by locally controlling the temperature field during FP via an external heat source. Second, it is shown that this method prevents unstable front propagation and quenching despite adverse initial and boundary conditions. Third, it is shown that this method minimizes cure time and energy consumption compared to bulk heating. Dicyclopentadiene ; Overheating (electricity) ; Polymerization ; Materials science ; Mechanics ; Front velocity ; Control theory (sociology) ; Boundary value problem ; Front (military) ; Thermodynamics ; Composite material ; Physics ; Computer science ; Mechanical engineering ; Mathematics ; Engineering ; Control (management) ; Polymer ; Mathematical analysis Photopolymerization techniques and applications ; Dental materials and restorations ; Dyeing and Modifying Textile Fibers
Authors: M. Koubiti | Malo Kerebel
Source: Journal of Physics Conference Series (article, 2023-01-01)
Field: Chemistry — Spectroscopy

Introducing Machine-Learning in Spectroscopy for Plasma Diagnostics and Predictions Abstract Artificial Intelligence (AI) and data science techniques are increasingly introduced in physics including plasma physics where Machine Learning (ML) is applied to emission spectroscopy for plasma parameter determination. Recently, the open-access python-based Sickit-Learn ML platform was used to analyze line intensities in the order to infer the plasma electron densities and temperatures for conditions relevant to tokamak divertors. In this paper, we discuss the application of deep-learning (DL) to synthetic line spectra for conditions of magnetic fusion plasmas with hydrogen-deuterium (H-D) mixtures. The idea will be illustrated through application of Artificial Neural Networks (ANN) to spectra of the Balmer-α line emitted by H-D mixtures, the aim being to obtain the isotopic ratios. The objective of our approach is to provide a new method to infer the hydrogen isotopic ratio sufficiently fast that can be exploited for real-time applications. We will demonstrate the proof-of-principle of our method through the application of a TensorFlow DL regression algorithm to theoretical line spectra generated with predetermined parameters. Tokamak ; Plasma ; Balmer series ; Spectral line ; Spectroscopy ; Python (programming language) ; Artificial neural network ; Machine learning ; Artificial intelligence ; Computational physics ; Line (geometry) ; Computer science ; Physics ; Algorithm ; Atomic physics ; Emission spectrum ; Nuclear physics ; Mathematics ; Quantum mechanics Mass Spectrometry Techniques and Applications ; Magnetic confinement fusion research ; Laser-induced spectroscopy and plasma
Authors: M. Shaheer Malik | Shaikh Faazil | Meshari A. Alsharif | Qazi Mohammad Sajid Jamal | Jabir H. Al‐Fahemi | Amrita Banerjee | Arpita Chattopadhyay | Samir Kumar Pal | Ähmed Kamal | Saleh A. Ahmed
Source: Pharmaceuticals (article, 2023-03-30)
Field: Chemistry — Organic Chemistry

Antibacterial Properties and Computational Insights of Potent Novel Linezolid-Based Oxazolidinones The mounting evidence of bacterial resistance against commonly prescribed antibiotics warrants the development of new antibacterial drugs on an urgent basis. Linezolid, an oxazolidinone antibiotic, is a lead molecule in designing new oxazolidinones as antibacterial agents. In this study, we report the antibacterial potential of the novel oxazolidinone-sulphonamide/amide conjugates that were recently reported by our research group. The antibacterial assays showed that, from the series, oxazolidinones <b>2</b> and <b>3a</b> exhibited excellent potency (MIC of 1.17 μg/mL) against <i>B. subtilis</i> and <i>P. aeruginosa</i> strains, along with good antibiofilm activity. Docking studies revealed higher binding affinities of oxazolidinones <b>2</b> and <b>3a</b> compared to linezolid, which were further validated by molecular dynamics simulations. In addition to this, other computational studies, one-descriptor (log <i>P</i>) analysis, ADME-T and drug likeness studies demonstrated the potential of these novel linezolid-based oxazolidinones to be taken forward for further studies. Linezolid ; Computer science ; Computational biology ; Medicine ; Staphylococcus aureus ; Biology ; Bacteria ; Vancomycin ; Genetics Synthesis and biological activity ; Phenothiazines and Benzothiazines Synthesis and Activities ; Computational Drug Discovery Methods
Authors: Martha Ilett | Eleena Naveed | Teresa Roncal‐Herrero | Zabeada Aslam | Stuart Micklethwaite | Nicole Hondow
Source: Journal of Nanoparticle Research (article, 2023-06-01)
Field: Materials Science — Materials Chemistry

In situ electron microscopy techniques for nanoparticle dispersion analysis of commercial sunscreen Abstract Nanoparticles are common active ingredients within many commercial products including sunscreen. Consequently, accurate characterisation of nanoparticles in these products is vital to enhance product design, whilst also understanding the toxicological implications of these nanoparticles. Whilst bulk techniques are useful in providing some information, they often cannot resolve individual particles, and therefore electron microscopy can be used for high-resolution nanoparticle characterisation. However, conventional high vacuum dry TEM does not accurately represent nanoparticle dispersions and other in situ methods must be used. Here, we use a combination of techniques including liquid cell transmission electron microscopy (LCTEM), cryogenic (cryo)-TEM and cryo-scanning electron microscopy (SEM) to characterise a commercial sunscreen containing titanium dioxide (TiO 2 ) and zinc oxide (ZnO) nanoparticles. Our work illustrates that whilst LCTEM does not require any sample preparation more beam artefacts can occur causing ZnO dissolution with only TiO 2 nanoparticles visualised. Comparatively, cryo-TEM allows characterisation of both ZnO and TiO 2 , yet only cryo-SEM could be used to analyse the pure product (without dilution) but biased the characterisation to the larger fraction of nanoparticles and agglomerates. Ultimately, only with a combination of different in situ EM techniques can an accurate characterisation of commercial products be achieved in order to ensure effective and safe product design and manufacture. Materials science ; Nanoparticle ; Transmission electron microscopy ; Nanotechnology ; Dissolution ; Scanning electron microscope ; Characterization (materials science) ; Sample preparation ; Microscopy ; Agglomerate ; Titanium dioxide ; Chemical engineering ; Metallurgy ; Composite material ; Optics ; Chromatography ; Chemistry Nanoparticles: synthesis and applications ; Gold and Silver Nanoparticles Synthesis and Applications ; TiO2 Photocatalysis and Solar Cells
Authors: Louis A. Angeloni | Sergey V. Baryshev | Matthias Mühle | W. Andreas Schroeder
Source: Physical review. B./Physical review. B (article, 2023-04-04)
Field: Materials Science — Materials Chemistry

Spectral emission properties of a nitrogen-doped diamond (001) photocathode: Hot electron transport and transverse momentum filtering The electron emission properties of a single-crystal nitrogen-doped diamond(001) photocathode inserted in a 10 kV DC photoelectron gun are determined using a tunable (235--410 nm) ultraviolet laser radiation source for photoemission from both the back nitrogen-doped substrate face and the front homoepitaxially grown and undoped diamond crystal face. The measured spectral trends of the mean transverse energy and quantum efficiency of the emitted electrons are both anomalous and nonmonotonic, but are shown to be consistent with (i) the known physics of electron photoexcitation from the nitrogen substitution states into the conduction bands of diamond, (ii) the energy position and dispersion characteristics of the conduction bands of diamond in the (001) emission direction, (iii) the effective electron affinity of the crystal faces, (iv) the strong electron-(optical)phonon coupling in diamond, and (v) the associated hot electron transport dynamics under energy equipartition with the optical phonons. Notably, the observed hot electron emission is shown to be restricted parallel to the photocathode surface by the low transverse effective masses of the emitting band states---a transverse momentum filtering effect. Photocathode ; Diamond ; Electron ; Materials science ; Atomic physics ; Crystal (programming language) ; Physics Diamond and Carbon-based Materials Research ; Advanced Electron Microscopy Techniques and Applications ; Photocathodes and Microchannel Plates
Authors: Elke Völkle | Fabian Schulz | Julia Maxi Kanold | Monika Michaelis | Kerstin Wissel | Franz Brümmer | Anna S. Schenk | Sabine Ludwigs | Joachim Bill | Dirk Rothenstein
Source: Journal of Materials Chemistry B (article, 2023-01-01)
Field: Materials Science — Biomaterials

Functional mimicry of sea urchin biomineralization proteins with CaCO<sub>3</sub>-binding peptides selected by phage display The intricate process of biomineralization, <i>e.g.</i> in sea urchins, involves the precise interplay of highly regulated mineralization proteins and the spatiotemporal coordination achieved through compartmentalization. However, the investigation of biomineralization effector molecules, <i>e.g.</i> proteins, is challenging, due to their very low abundance. Therefore, we investigate the functional mimicry in the bioinspired precipitation of calcium carbonate (CaCO<sub>3</sub>) with artificial peptides selected from a peptide library by phage display based on peptide-binding to calcite and aragonite, respectively. The structure-directing effects of the identified peptides were compared to those of natural protein mixes isolated from skeletal (test) structures of two sea urchin species (<i>Arbacia lixula</i> and <i>Paracentrotus lividus</i>). The calcium carbonate samples deposited in the absence or presence of peptides were analyzed with a set of complementary techniques with regard to morphology, polymorph, and nanostructural motifs. Remarkably, some of the CaCO<sub>3</sub>-binding peptides induced morphological features in calcite that appeared similar to those obtained in the presence of the natural protein mixes. Many of the peptides identified as most effective in exerting a structure-directing effect on calcium carbonate crystallization were rich in basic amino acid residues. Hence, our <i>in vitro</i> mineralization study further highlights the important, but often neglected, role of positively charged soluble organic matrices associated with biological and bioinspired CaCO<sub>3</sub> deposition. Biomineralization ; Calcium carbonate ; Sea urchin ; Calcite ; Peptide ; Aragonite ; Strongylocentrotus purpuratus ; Peptide sequence ; Paracentrotus lividus ; Biology ; Amino acid ; Mineralization (soil science) ; Biochemistry ; Biophysics ; Chemistry ; Cell biology ; Mineralogy ; Gene ; Ecology Calcium Carbonate Crystallization and Inhibition ; Cephalopods and Marine Biology ; Marine Biology and Environmental Chemistry
Authors: Hengkai Guo | Jack S. Baker | Wei Wu | Kwang‐Leong Choy
Source: Advanced Physics Research (article, 2023-03-24)
Field: Materials Science — Materials Chemistry

High Dielectric Constants in BaTiO<sub>3</sub> Due to Phonon Mode Softening Induced by Lattice Strains: First Principles Calculations Abstract High‐dielectric‐constant materials attract much attention due to their broad applications in modern electronics. Barium titanate (BTO) is an established material possessing an ultrahigh dielectric constant; however, a complete understanding of the responsible underlying physical mechanism remains elusive. Here a set of density‐functional‐theory calculations for the static dielectric tensors of barium titanate under strain has been performed. The dielectric constant increases to ≈7300 under strain. The analysis of the computed vibrational modes shows that transverse vibrational mode softening (the appearance of low‐frequency modes) is responsible for this significant increase as driven by the relationship between lattice contribution for the static dielectric constant ( k ) and vibrational frequency (ω), i.e., . The relevant vibrational mode indicates a large counter‐displacement of Ti ions and O anions, which greatly enhances electrical dipoles to screen the electric field. The calculations not only interpreted experimental data on the high dielectric constants of BTO, where the lattice deformation due to the strains from the grain nanostructure plays an important role, but also pointed to exploring high‐throughput calculations to facilitate the discovery of the advanced dielectric materials. Moreover, the calculations can prove useful for doped BTO, for which local strains fields can be achieved using defect engineering. Dielectric ; Materials science ; Barium titanate ; Phonon ; Condensed matter physics ; High-κ dielectric ; Softening ; Dipole ; Lattice constant ; Ferroelectricity ; Molecular vibration ; Raman spectroscopy ; Composite material ; Optoelectronics ; Optics ; Physics ; Diffraction ; Quantum mechanics Ferroelectric and Piezoelectric Materials ; Dielectric properties of ceramics ; Semiconductor materials and devices