jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Muhammad Nasir | Ryuhei Yamaguchi | Yun She | Anindityo Patmonoaji | Mohammad Azis Mahardika | Weicen Wang | Zijing Li | Shintaro Matsushita | Tetsuya Suekane
Source: Applied Sciences (article, 2022-05-17)
Field: Materials Science — Materials Chemistry

Hydrodynamic Fingering Induced by Gel Film Formation in Miscible Fluid Systems: An Experimental and Mathematical Study Hydrodynamic fingering induced by gel formation shares common features with growing biofilms, bacterial colonies, and the instability of a confined chemical garden. Fluid displacement with gel formation is also essential in various engineering applications, including CO2 leakage remediation from storage reservoirs and enhanced oil recovery. We conducted Hele-Shaw cell displacement experiments for a miscible fluid system using skim milk and aqueous citric acid solution. This study aimed to investigate the effects of gel film formation on the fingering instability of a miscible fluid system and develop a mathematical model of the sequential growth of gel film formation at the fingertip. We found that the gel film formation thickens with time, resulting in instability at the interface. A distinctive fingering pattern, resembling tentacles, appears where miscibility is suppressed, and the growth of the finger is localized at the fingertip. The finger width remains constant with increasing flow rate, whereas the number of fingers increases linearly before the fingers merge. The gap width significantly limits the finger width. Finally, a mathematical model of sequential film thickness growth for a bubble-like fingertip structure was developed. This model is based upon the interplay between the diffusion of citric acid through the existing gel film formation and elongation of the fingertip. The model provides an understanding of the fundamental mechanism of the growth of the bubble-like fingertip. Viscous fingering ; Instability ; Materials science ; Pattern formation ; Mechanics ; Chemical engineering ; Composite material ; Porous medium ; Engineering ; Porosity ; Physics Pickering emulsions and particle stabilization ; Fluid Dynamics and Heat Transfer ; Surface Modification and Superhydrophobicity
Authors: Kevin R. Pilkiewicz | Pratip Rana | Michael L. Mayo | Preetam Ghosh
Source: Mobile Networks and Applications (article, 2022-12-01)
Field: Materials Science — Materials Chemistry

Predicting Supramolecular Structure from the Statistics of Individual Molecular Events Abstract As manipulating the self-assembly of supramolecular and nanoscale constructs at the single-molecule level increasingly becomes the norm, new theoretical scaffolds must be erected to replace the thermodynamic and kinetics based models used to describe traditional bulk phase syntheses. Like the statistical mechanics underpinning these latter theories, the framework we propose uses state probabilities as its fundamental objects; but, contrary to the Gibbsian paradigm, our theory directly models the transition probabilities between the initial and final states of a trajectory, foregoing the need to assume ergodicity. We leverage these probabilities in the context of molecular self-assembly to compute the overall likelihood that a specified experimental condition leads to a desired structural outcome. We demonstrate the application of this framework to a toy model in which N identical molecules can assemble into oligomers of different lengths and conclude with a discussion of how the high computational cost of such a fine-grained model can be overcome through approximation when extending it to larger, more complex systems. Leverage (statistics) ; Computer science ; Statistical physics ; Ergodicity ; Context (archaeology) ; Supramolecular chemistry ; Statistical mechanics ; Theoretical computer science ; Artificial intelligence ; Molecule ; Mathematics ; Physics ; Statistics ; Quantum mechanics Block Copolymer Self-Assembly ; Supramolecular Chemistry and Complexes ; Spectroscopy and Quantum Chemical Studies
Authors: Rihards Aleksis | Reji Nedumkandathil | Wassilios Papawassiliou | José P. Carvalho | Aleksander Jaworski | Ulrich Häußermann | Andrew J. Pell
Source: ChemRxiv (preprint, 2022-09-21)
Field: Chemistry — Spectroscopy

Probing the electronic structure and hydride occupancy in barium titanium oxyhydride through DFT-assisted solid-state NMR Perovskite-type oxhydrides such as BaTiO3−xHy exhibit mixed hydride ion and electron conduction and are an attractive class of materials for developing energy storage devices. However, the underlying mechanism of electric conductivity and its relation to the composition of the material remains unclear. Here we report detailed insights into the hydride local environment, the electronic structure and hydride conduction dynamics of barium titanium oxyhydride. We demonstrate that DFT-assisted solid-state NMR is an excellent tool for differentiating between the different feasible electronic structures in these solids. Our results indicate that upon reduction of BaTiO3 the introduced electrons are delocalized among all Ti atoms forming a bandstate. Furthermore, each vacated anion site is reoccupied by at most a single hydride, or else remains vacant. This single occupied bandstate structure persists at different hydrogen concentrations (y = 0.13−0.31) and a wide range of temperatures (∼ 100−300 K). Hydride ; Delocalized electron ; Electronic structure ; Materials science ; Ion ; Hydrogen ; Titanium ; Chemical physics ; Crystallography ; Inorganic chemistry ; Chemistry ; Computational chemistry ; Organic chemistry Advanced NMR Techniques and Applications ; Advanced Condensed Matter Physics ; Hydrogen Storage and Materials
Authors: Andrea Di Ronco | Stefano Lorenzi | Francesca Giacobbo | Carolina Introini | Antonio Cammi
Source:  (article, 2022-01-01)
Field: Materials Science — Materials Chemistry

Development of an OpenFOAM Multiphysics Solver for Solid Fission Products Transport in the Molten Salt Fast Reactor The analysis of innovative reactor concepts such as the Molten Salt Fast Reactor (MSFR) requires the development of new modeling and simulation tools. In the case of the MSFR, the strong intrinsic coupling between thermal-hydraulics, neutronics and fuel chemistry has led to the adoption of the multiphysics approach as a state-of-the-art paradigm.&#13;\nOne of the peculiar aspects of liquid-fuel reactors such as the MSFR is the mobility of fission products (FPs) in the reactor circuit. Some FP species appear in form of solid precipitates carried by the fuel flow and can deposit on reactor boundaries (e.g., heat exchangers), potentially representing design issues related to the degradation of heat exchange performance or radioactive hotspots. The integration of transport models for solid particles in multiphysics codes is therefore relevant for the prediction of deposited fractions.&#13;\nTo this aim, we develop a multiphysics solver based on the OpenFOAM library to address the issue of solid fission products transport. Single-phase incompressible thermal hydraulics are coupled with neutron diffusion, and advection-diffusion-decay equations are implemented for fission products concentrations. Particle deposition and precipitation are considered as well.&#13;\nThe developed solver is tested on two different MSFR application to showcase the capabilities of the solver in steady-state simulation and to investigate the role of precipitation and turbulence modeling in the determination of particle concentration distributions. Multiphysics ; Molten salt ; Solver ; Nuclear engineering ; Molten salt reactor ; Fission ; Fission products ; Materials science ; Computer science ; Nuclear physics ; Engineering ; Physics ; Thermodynamics ; Finite element method ; Neutron ; Metallurgy Nuclear Materials and Properties ; Nuclear reactor physics and engineering ; Fusion materials and technologies
Authors: Shuzo Kutsuna | Naoki Kaneyasu
Source: Environmental Science Atmospheres (article, 2022-01-01)
Field: Chemistry — Inorganic Chemistry

A laboratory study on the uptake of gaseous molecular iodine by clay minerals at different relative humidities Laboratory experiments on the uptake of I 2 by clay minerals support separate estimates of radioiodine dry deposition processes before and after sunrise when I 2 is released at night. Iodine ; Clay minerals ; Environmental chemistry ; Chemistry ; Mineralogy ; Environmental science ; Organic chemistry Radioactive element chemistry and processing ; Radioactive contamination and transfer ; Nuclear materials and radiation effects
Authors: Yuhui Jin | Aize Li | Ross Stewart | Robert R. Hancock | David E. Baker | Ruchirej Yongsunthon | Kelleen K. Hughes | D. L. Weidman
Source: Scientific Reports (article, 2022-01-18)
Field: Materials Science — Surfaces, Coatings and Films

A template-free, more environmentally friendly approach for glass micro-texturing Micron and nanometer size textured silicate glass surfaces are of interest in consumer electronics, photovoltaics, and biosensing applications. Typically, texturing glass surfaces requires applying a patterned mask or a pre-etching treatment (e.g. sandblasting) on the glass substrate, followed by a mask transferring or etching process using a fluoride-containing compound. The major challenges of such a process are the complexity and cost of masking, and the safety and environmental concerns around the usage and disposal of hydrofluoric acid. Here, we describe a template-free method to construct micron-sized and submicron-sized texture on isotropic glass surfaces in one step. The new texturing mechanisms are well supported by experimental data and peridynamic simulations. With this novel strategy, the etchant uses fluoride-free chemicals such as citric acid to texture silicate glass. Etchant concentration, etch temperature, time, and additives are the primary parameters that dictate the texturing process. Surface feature size and depth can be independently controlled by tuning the leaching and chemical polishing process. We hope this study can trigger more research on novel and more environmentally friendly texturing of isotropic materials. Environmentally friendly ; Computer science ; Nanotechnology ; Materials science ; Biology ; Ecology Surface Modification and Superhydrophobicity ; Advanced ceramic materials synthesis ; Silicone and Siloxane Chemistry
Authors: Jean-Charles Agopian
Source: theses.fr (ABES) (preprint, 2022-12-02)
Field: Materials Science — General Materials Science

Development, characterisation and optimisation of hybrid composite materials Climate change will require a more sober industry, in which “green” materials may play a key role. This also applies to composite materials, and every possibility to reduce their carbon footprint might be considered, while maintaining acceptable performance and durability levels.Partial replacement of carbon fibres by flax fibres is for instance a way to reduce the environmental impact of these composite materials. Surface energies of the fibres being quite different, the properties of the composite materials resulting of such a hybridisation might not be optimised. Moreover, flax fibres are hydrophilic, which rises two problems: they are poorly compatible with hydrophobic polymers, and can lead to a decrease of the durability of the composite, more susceptible to absorb water.In this study, a treatment by direct fluorination by molecular fluorine F2 has been implemented, aiming at level the surface energies of the fibres and increase their affinity with the matrix polymer. This work is mainly dedicated to the fluorination of carbon fibres, while another simultaneous doctoral project focused on flax fibre fluorination.First, a state of the art on the fluorination of carbon fibres has been realised, and published as a literature review, where the versatility of the carbon-fluorine bond and the experimental conditions leading influencing it were carefully described.It has then been shown by a wide variety of physicochemical analyses that room-temperature fluorination of carbon fibres was a way to fluorinate their sizing, and thus to tailor their surface energy. The same treatment was carried on a wide temperature scale, successively highlighting a sizing fluorination and hyperfluorination, and then a fluorination of the carbon fibre, leading to a huge increase of its hydrophobicity, and a decrease of its polar component.These fluorinated carbon and flax fibres were then integrated in an epoxy matrix by infusion process, with several stacking sequences. Mechanical tests do not show an improvement of the fibre-matrix compatibility thanks to fluorination, which might be explained by the high-quality interface allowed by sizing for the non-fluorinated fibres. Wet ageing tests are however promising, as composites made with fluorinated fibres absorb less water than composites made with non-fluorinated fibres. Composite number ; Materials science ; Engineering ; Composite material Material Properties and Applications ; Silicone and Siloxane Chemistry ; Additive Manufacturing and 3D Printing Technologies
Authors: Nadia Curie Dempowo
Source: SPIRE - Sciences Po Institutional REpository (preprint, 2022-11-08)
Field: Materials Science — Materials Chemistry

Consideration of cationic interdiffusion for modeling the sintering of nuclear ceramics at the grain scale During the sintering of MOX fuel, the interdiffusion of U and Pu cations leads to its chemical homogenization. Bulk interdiffusion represents the slowest phenomenon, leading to the final intragranular homogeneity of the fuel. The multicomponent diffusion of U and Pu was studied taking into account the fast diffusion of the oxide ions compared to the metal cations. The modeling of this mechanism in 1D by finite differences allowed to conclude that the boundary conditions of Neumann based on the balance of flux are suitable for the modeling of crystallites, while those of Dirichlet are a sufficient approximation for the modeling of polycrystals with larger sizes. Diffusion coefficients were adjusted and the model checked on the basis of experimental work previously carried out at the Fuel Research Department. The quantitative study of homogenization in microstructures with unimodal and multimodal distributions showed a delay in homogenization for large grains in microstructures with variable grain size. 2D modeling by finite elements made it possible to analyze the effect of intergranular contact zones as an accelerator of homogenization. 3D finite element modeling showed the increase in homogenization time for large-scale heterogeneous microstructures. This work made it possible to theoretically formulate the multiphysical sintering model by proposing a coupling of the diffusion of mechanical and chemical origin, on the surface, at the grain boundaries and in volume, thus contributing to the advancement of the Salammbo sintering code. Sintering ; Ceramic ; Scale (ratio) ; Materials science ; Cationic polymerization ; Metallurgy ; Geography ; Cartography Nuclear Materials and Properties ; Nuclear materials and radiation effects ; Thermodynamic and Structural Properties of Metals and Alloys
Authors: Yu Han | Wenkui Hao | Lingling Xu | Xin Chen | Yan Jin | Xinghui Zhang | Yun Chen | Luyao Huang | Bingkun Yang | Zhixiang Zhu | Xiaofang Wang
Source: Research Square (preprint, 2022-10-17)
Field: Materials Science — Materials Chemistry

Classification and spatial mapping of atmospheric corrosion of China Abstract Atmospheric corrosion is ubiquitous in China but varies a lot among different regions covering the cold, temperate and tropical zones. Categorizing the atmospheric corrosivity and plotting precise atmospheric corrosion map remain key interest for a variety of industries. The present work proposed an atmospheric corrosion map of China for hot-dip galvanized steels, which was constructed by inverse distance weighting (IDW) interpolation algorithm based on both the measured corrosion rates of coupons exposed at 2393 inland test stations and calculated corrosion rates from a prevalent dose-response function in 2918 sites in coastal regions. When the corrosion category was used as the criterion, the IDW interpolation algorithm of power 2 performed best. Cross-validation results confirmed that the prediction accuracy of IDW interpolation reached 85.6%. Based on the corrosion map, the categories of atmospheric corrosivity of China could be determined. The atmospheric corrosion map shows C2 (50.07%) and C3 (44.14%) zones cover the vast majority of China. C4-CX categories (highly corrosive regions) account for 4.07% (390760 km 2 ) of China. Inverse distance weighting ; Corrosion ; Multivariate interpolation ; Weighting ; Interpolation (computer graphics) ; Environmental science ; China ; Metallurgy ; Materials science ; Geography ; Computer science ; Mathematics ; Statistics Corrosion Behavior and Inhibition ; Concrete Corrosion and Durability ; Structural Integrity and Reliability Analysis
Authors: Arun S. Mujumdar | Sabah Mounir | Ezzeddine Amami | Sihem Bellagha | Colette Besombes | Carmen Tellez Perez | Wafa Hajji | Victor Lefrançois | Tamara Allaf | Mohamed W. Negm | Chaima Rekik | Maritza Alonzo Macías | Hela Gliguem | Leila Benhajjsaid
Source: Proceedings of the 22nd International Drying Symposium on Drying Technology - IDS '22 (article, 2022-08-09)
Field: Materials Science — General Materials Science

Swell-drying by DIC coupled with a specific intensification of the Drying operations The various studies and numerous industrial applications of swell-drying have had high relevance in combining conventional drying processes with instant controlled pressure-drop (DIC). The operation leads to highly relevant solutions against various well-known issues specific to drying, such as the texture defects resulting from shrinkage/collapse, microbiological contamination, etc. An international team has conducted complementary studies of phenomenological models and experimental trials to define different variants of the new Interval Hyperactive Drying (IHAD) processes, including Interval Starting-Accessibility Drying and Interval Microwave cold Airflow Drying, Interval Flash Autovaporization Drying, Interval Infrared Airflow Drying, etc. All these operations involve cycles of two mechanisms of vapor generation/transport stage and an internal water diffusion stage. These operations improve both process performance and final product quality directly issued from lower energy consumption and absence of Casehardening and thermal biochemical degradation. The total time length of continuous drying and the tempering periods of IHAD are closely correlated with the diffusivity of water within the structure of the solid. By involving in such conventional or interval drying operations a DIC-texturing, drying kinetics becomes much better, saving energy consumption and improving the product quality of heat-sensitive solids, thus leading to design and manufacture efficient industrial scale driers. Swell ; Environmental science ; Physics ; Thermodynamics Material Properties and Applications ; Induction Heating and Inverter Technology
Authors: Xingchun Li | Ying Zhou | Hui Li | Feng Zhan | Yucheng Liu | Ziming Wang | Wenwen Tu
Source: Research Square (preprint, 2022-05-11)
Field: Chemistry — Analytical Chemistry

Investiation on the pollution release characteristics of subgrade base materials prepared by thermal desorption residues of oil-based cuttings Abstract The thermal desorption residues of oil-based drilling cuttings’ final destination managements are still strict because of the unclear pollution characteristics of its resource products. The thermal desorption residues were prepared into subgrade base materials, and the semi-dynamic leaching tests were used to simulate the leaching characteristics of pollutants under extremely acidic conditions. In the semi-dynamic test, the concentrations of pollutants such as naphthalene, anthracene, benzo(a)anthracene, dibenzo(a,h)anthracene, Cd, and Zn meet the Class III water quality requirements of “Standard for groundwater quality”(GB/T 14848-2017). According to Fick’s second law, the release of naphthalene, anthracene, benzo(a)anthracene, dibenzo(a,h)anthracene, and Cd of leaching is dominated by diffusion; the release of benzo(a)pyrene and Zn of leaching is mainly dissolution. The release law and characteristics of pollutants were explored when thermal desorption residues were applied as subgrade base materials, which provided an important reference basis for the resource and utilization of thermal desorption residues. Anthracene ; Desorption ; Thermal desorption ; Naphthalene ; Leaching (pedology) ; Environmental chemistry ; Pollutant ; Chemistry ; Pollution ; Environmental science ; Organic chemistry ; Soil water ; Adsorption ; Soil science Petroleum Processing and Analysis ; Drilling and Well Engineering ; Hydraulic Fracturing and Reservoir Analysis
Authors: Arthur Alexandre
Source: SPIRE - Sciences Po Institutional REpository (preprint, 2022-09-15)
Field: Chemistry — Physical and Theoretical Chemistry

Dispersion dans les milieux hétérogènes : une étude des effets hydrodynamiques et de la diffusion médiée par la surface. Cette thèse a pour objet l'étude de la dispersion, c'est à dire la vitesse d'étalement de particules traceurs, dans des milieux hétérogènes, présentant une périodicité spatiale. Ce processus se quantifie par un coefficient de diffusivité effective. Il est bien connu que la présence de parois ou d'obstacles diminue la dispersion, tandis qu'un écoulement de cisaillement a pour effet de l'augmenter. Cependant, la plupart des études considèrent des parois parfaitement réfléchissantes. Dans un premier chapitre, nous dérivons une expression générale de la diffusivité effective pour un modèle de diffusion médiée par la surface qui inclut la possibilité pour les particules d'adhérer et de diffuser sur les parois. En appliquant cette formule à deux systèmes (un réseau d'obstacles sphériques et un canal périodique), nous montrons que ce mécanisme d'adhésion permet d'augmenter la dispersion par rapport au cas de parois réfléchissantes, et ce même si la diffusion à la surface est plus lente que dans le volume. Dans un deuxième temps, nous examinons les effets combinés d'un écoulement visqueux et du confinement sur la dispersion dans un canal ondulé. Nous mettons en évidence à l'aide d'expressions analytiques la compétition entre ces deux effets antagonistes dans la limite de faibles ondulations des parois. Dans la limite opposée, les fortes ondulations des parois ont pour effet de piéger les particules traceurs. Nous mettons en évidence à l'aide de l'expression de la diffusivité une équivalence avec un problème de dispersion de Taylor dans un canal uniforme dont les parois sont partiellement adsorbantes. Dans un troisième temps, nous prenons en compte simultanément l'ondulation des parois, l'écoulement visqueux ainsi que la possibilité d'adhésion aux surfaces. En dérivant un formalisme général, nous montrons que la combinaison de ces trois paramètres induit des effets non-triviaux sur la dispersion. Dans un dernier chapitre, nous nous intéressons à la dynamique d'une particule Brownienne confinée dans un canal plat. Nous dérivons une expression généralisée de la diffusivité de Taylor en exprimant le deuxième cumulant. De même, nous quantifions la non-gaussianité de la distribution en position suivant l'axe du canal en étudiant analytiquement les cumulants d'ordres supérieurs. Dispersion (optics) ; Diffusion ; Surface (topology) ; Mechanics ; Statistical physics ; Materials science ; Physics ; Mathematics ; Optics ; Thermodynamics ; Geometry Electrostatics and Colloid Interactions