jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Sidore, Sidore | M. Sidore | Kudashova, Anastasiia | A. Kudashova | Gori, Matteo | Pettini, Marco | J. Torres | L. Varani
Source: Infoscience (Ecole Polytechnique Fédérale de Lausanne) (preprint, 2019-08-23)
Field: Chemistry — Physical and Theoretical Chemistry

Using the velocity auto-correlation function to characterize functional ”noise” in bio-molecules International audience Noise (video) ; Fourier transform ; Correlation function (quantum field theory) ; Function (biology) ; Biological system ; Computer science ; Statistical physics ; Range (aeronautics) ; Cross-correlation ; Correlation ; Algorithm ; Physics ; Mathematics ; Artificial intelligence ; Mathematical analysis ; Engineering ; Spectral density ; Image (mathematics) ; Aerospace engineering thermodynamics and calorimetric analyses ; Spectroscopy and Quantum Chemical Studies
Authors: Lanyuan Lu
Source: Carolina Digital Repository (University of North Carolina at Chapel Hill) (article, 2019-08-15)
Field: Chemistry — Organic Chemistry

Molecular dynamics simulation of amphiphilic aggregates In this dissertation, molecular dynamics simulations were performed for systems containing amphiphilic aggregates, such as monolayers, bilayers, and reverse micelles. Various analysis methods were used in order to investigate structural and dynamical properties and solve particular problems for different systems. First, we present simulations where we observed successful self-assembly of reverse micelles in a three-component system containing supercritical CO2, water, and fluorinated surfactant starting from random configurations. Such self-assembly allows for the future computational study of structural and thermodynamic properties of microemulsions in water/CO2 systems that will be less dependent on the initial conditions. Next, a series of molecular dynamics simulations were performed to study the PFPE (perfluoropolyether) and PE (polyether) surfactant monolayers and micelles at the water/supercritical carbon dioxide interface. We observed that values of intramolecular bonded interaction parameters which are related to chain rigidity determine the monolayer surface pressure. We show that good and bad properties of PFPE/PE surfactants are connected to conformational entropy. In order to study the effect of the hydration force, we simulated systems with model hydrophilic plates. We studied the effect of charge correlation on the potential of mean force between plates. The orientational structure of water between the plates was investigated to understand the effect of molecular structure of water on the properties of the potential of mean force. Finally, we calculated the free energy cost for removing a cholesterol molecule from two different lipid bilayers. The results can help us to understand the relationship between the lipid structure and the lipid-cholesterol affinity. N-palmitoyl-sphingomyelin was found to have a better cholesterol affinity compared with that of phosphatidylcholine lipid DPPC, according to our free energy values from molecular dynamics simulations. Amphiphile ; Molecular dynamics ; Dissipative particle dynamics ; Chemistry ; Amphiphilic molecule ; Computer science ; Dynamics (music) ; Nanotechnology ; Materials science ; Polymer ; Physics ; Copolymer ; Computational chemistry ; Organic chemistry Surfactants and Colloidal Systems ; Advanced Polymer Synthesis and Characterization ; Protein Interaction Studies and Fluorescence Analysis
Authors: Anthony Klepacki
Source: IDEALS (University of Illinois Urbana-Champaign) (article, 2019-04-25)
Field: Materials Science — Materials Chemistry

IGFEM modeling of transverse failure in carbon-epoxy composites and implementation of the IGFEM in Abaqus FEA A comprehensive analysis of the Interface-Enriched General Finite Element Method (IGFEM) using a modified trilinear cohesive law was performed to validate the model against experimental results showing good agreement in both initial composite stiffness and against strain measurements of the onset of transverse cracking performed on a [0/90/0] carbon/glass-epoxy laminate. Furthermore, a large dataset of realistic virtual microstructures is created from optical images of test specimens and was simulated to study the effects of microstrucutural geometric characteristics on the onset of initial cracking. Finally, a linear IGFEM formulation was implemented in the commercial finite element analysis package Abaqus through the use of common linear four-node tetrahedral elements and the User Element Library API. This implementation was verified against analytical and conforming mesh solutions. Epoxy ; Composite material ; Finite element method ; Materials science ; Transverse plane ; Structural engineering ; Engineering Material Properties and Failure Mechanisms ; Mechanical Behavior of Composites ; Geotechnical Engineering and Underground Structures
Authors: Steffen Kühn | Chintan Shah | J. R. Crespo López-Urrutia | Keisuke Fujii | René Steinbrügge | Jakob Stierhof | Moto Togawa | Zoltán Harman | Natalia S. Oreshkina | Charles Cheung | M. G. Kozlov | S. G. Porsev | M. S. Safronova | J. C. Berengut | Michael Rosner | M. Bissinger | Ralf Ballhausen | Natalie Hell | Sungnam Park | М. Chung | Moritz Hoesch | Jörn Seltmann | A. Surzhykov | V. A. Yerokhin | J. Wilms | F. S. Porter | Th. Stöhlker | Christoph H. Keitel | Thomas Pfeifer | G. V. Brown | Maurice A. Leutenegger
Source: DESY (CERN, DESY, Fermilab, IHEP, and SLAC) (article, 2019-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

High-resolution Photo-excitation Measurements Exacerbate the Long-standing Fe XVII Emission Problem We measured the L-shell soft X-ray fluorescence of Fe XVII ions in an electron beam ion trap following resonant photo-excitation using synchrotron radiation provided by the P04 beamline at PETRA III. Special attention is paid to two 2p-3d transitions, the 3C and 3D lines that are essential plasma diagnostics tools for astrophysics. Their resulting oscillator-strength ratio, f(3C)/f(3D) = 3.09(8)(6), is three times more accurate than previous results. The present ratio clearly departs by approximately 5-sigmas from the newest ab initio calculations but confirms previous laboratory measurements and astrophysical observations. A ten thousand-fold reduction in excitation-photon intensity and ten times higher spectral resolution allow us to exclude current explanations, reinstating a forty-year-old atomic-physics puzzle. Excitation ; High resolution ; Resolution (logic) ; Materials science ; Atomic physics ; Physics ; Computer science ; Remote sensing ; Geology ; Quantum mechanics ; Artificial intelligence Magnetism in coordination complexes ; X-ray Spectroscopy and Fluorescence Analysis ; Atomic and Molecular Physics
Authors: S.R. Guerra
Source: Padova Digital University Archive (Ateneo di Padova) (article, 2019-12-18)
Field: Materials Science — Materials Chemistry

Methanol gas-phase abatement in a membrane photoreactor by means of innovative nanocomposite catalysts The abatement of methanol (VOC) is studied by means of photocatalysis. Methanol contributes to indoor air pollution in confined environments. The abatement is performed in a new membrane photoreactor equipped with UV lamps. The membranes are formed by nanofibers produced via electrospinning, while catalyst are produced with innovative synthetic routes. The performance of different catalysts under UV-C irradiation are compared, leading to similar performances of the benchmark titanium dioxide. Methanol ; Catalysis ; Titanium dioxide ; Photocatalysis ; Membrane ; Nanocomposite ; Chemical engineering ; Materials science ; Nanofiber ; Electrospinning ; Chemistry ; Nanotechnology ; Composite material ; Organic chemistry ; Polymer Catalytic Processes in Materials Science ; Gas Sensing Nanomaterials and Sensors ; TiO2 Photocatalysis and Solar Cells
Authors: dwleeKAIST | bispl-kaist
Source: Zenodo (CERN European Organization for Nuclear Research) (article, 2019-12-08)
Field: Materials Science — Materials Chemistry

jongcye/CollaGAN_MRI: First release of our CollaGAN for MR Contrast Synthesis This is a CollaGAN software for MR contrast synthesis for the following paper : Dongwook Lee, Won-Jin Moon, and Jong Chul Ye, "Assessing the importance of magnetic resonance contrasts using collaborative generative adversarial networks", Nature Machine Intelligence. Contrast (vision) ; Computer science ; Chemistry ; Artificial intelligence Machine Learning in Materials Science ; Advanced MRI Techniques and Applications
Authors: A. Yu. Petrov | S. A. Sinitsin | В. И. Ванчурин | N.V. Nefedova | V. P. Kulikov
Source: Chemistry and Technology of Fuels and Oils (article, 2019-03-01)
Field: Materials Science — General Materials Science

Operational Perspectives of Molded Oxide Compositions in Catalytic Neutralization of Toxic Components of Gas Emissions from Industrial Equipment Catalysis ; Flue gas ; Oxide ; Chemical engineering ; Materials science ; Diffusion ; Process engineering ; Exhaust gas ; Chemistry ; Organic chemistry ; Metallurgy ; Engineering Material Properties and Applications
Authors: Kuldeep P. Waidya | S. Ramya Sri | T. Janaki
Source: Asian Journal of Pharmacy and Technology (article, 2019-01-01)
Field: Chemistry — Analytical Chemistry

Formulation Development and Characterisation of Repaglinide Buccal Tablets The objective of this study was to develop effective buccal tablets of Repaglinide. Tablets of Repaglinide were prepared by direct compression method using bioadhesive polymers like Chitosan, Guargum, Xanthan gum. Buccal tablets were prepared by taking polymers in different ratios. Buccal tablets were evaluated by different parameters such as thickness, hardness, weight uniformity, content uniformity, surface pH, in-vitro drug release, ex vivo drug permeation, in vivo mucoadhesive performance studies. In vitro assembly was used to measure the bioadhesive strength of tablets with fresh porcine buccal mucosa as model tissue. The tablets were evaluated for in vitro release in pH 6.8 phosphate buffer for 8 hr in standard dissolution apparatus. In order to determine the mode of release, the data was subjected to Zero order, first order, Higuchi, Korsmeyer and Peppas diffusion model. The formulation F3 showed maximum drug release (89.06%) in 8 hrs. The optimised formulation F3 showed a surface pH of 6.18. This formulation was following Zero order mechanism with regression value of 0.981. FT-IR studies revealed the absence of any chemical interaction between drug and polymers used. Repaglinide buccal tablets for buccal delivery could be prepared with required in-vitro release properties. Repaglinide ; Buccal administration ; Mathematics ; Medicine ; Traditional medicine ; Pharmacology ; Internal medicine Analytical Methods in Pharmaceuticals
Authors: Valadez Sánchez | Elvia Patricia
Source:  (article, 2019-01-01)
Field: Chemistry — Inorganic Chemistry

Insight into thin film SURMOFs The development of MOF-based technologies has been a focus point of research over the last 20 years resulting in ca. 70,000 published structures studied for a wide range of applications including gas storage and separation, drug delivery, chemical sensing, among others. Their research continues to be fueled by the continuous improvement of their thermal and mechanical features powering a bright future ahead. The synthesis of these materials has been one of the most investigated areas. When referring to the formation of homogeneous MOF thin films, the liquid phase epitaxial (LPE) layer-by-layer (LBL) formation has proven the acquisition of highly crystalline and oriented surface-mounted metal-organic frameworks (SURMOFs) suitable for integration as functional materials in multiple devices. In previous studies, ZIF-8 SURMOF synthesis via dipping at room temperature was systematically studied for alkane/alkene gas separation. Permeances and separation factors obtained agreed with other published synthesis techniques, but a great window of opportunity towards commercial feasibility still exists. Currently, this systematic approach is now being complemented with the incorporation of nanoparticles (e.g., Au, Pt) in various SURMOF systems to determine their potential in the field of catalysis of gaseous systems. Additionally, a comprehensive understanding of the properties and transport mechanisms of these SURMOF films is required in order to further enhance their performance. In previous works, the Maxwell-Stefan surface diffusion model was employed to gather a general understanding of the ZIF-8 SURMOF and other porous systems. To deepen our theoretical knowledge of these systems, various SURMOF films are being further characterized, including the acquisition of proper adsorption data at higher temperatures and pressures, surface diffusivities, and the consideration of micro-defects; this data is of high importance for further simulation studies. By doing so, the successful design, development, and application of novel SURMOF materials might be facilitated. Nanotechnology ; Materials science ; Homogeneous ; Thin film ; Porosity ; Metal-organic framework ; Nanoparticle ; Process engineering ; Chemistry ; Organic chemistry ; Engineering ; Physics ; Adsorption Metal-Organic Frameworks: Synthesis and Applications ; Machine Learning in Materials Science ; Gas Sensing Nanomaterials and Sensors
Authors: Matthew Egbert | Jean-Sébastien Gagnon | Juan Pérez‐Mercader
Source: Figshare (article, 2019-01-01)
Field: Chemistry — Physical and Theoretical Chemistry

Supplementary material from "From chemical soup to computing circuit: transforming a contiguous chemical medium into a logic gate network by modulating its external conditions" It has been shown that it is possible to transform a well-stirred chemical medium into a logic gate simply by varying the chemistry’s external conditions (feed rates, lighting conditions, etc.). We extend this work, showing that the same method can be generalized to spatially extended systems. We vary the external conditions of a well-known chemical medium (a cubic autocatalytic reaction–diffusion model), so that different regions of the simulated chemistry are operating under particular conditions at particular times. In so doing, we are able to transform the initially uniform chemistry, not just into a single logic gate, but into a functionally integrated network of diverse logic gates that operate as a basic computational circuit known as a full-adder. Logic gate ; Computer science ; Nanotechnology ; Electrical engineering ; Materials science ; Engineering Various Chemistry Research Topics ; Electrochemical sensors and biosensors
Authors: Won-Kyu Kim
Source: Repositorio Institucional de la Universidad de Málaga (University of Málaga) (article, 2019-06-12)
Field: Chemistry — Organic Chemistry

Selective permeability in gels: Beyond the solution-diffusion model Permeability, a measure of potential transport of macromolecules through crowded media such as hydrogels, determines important control parameters in bio-soft functional material applications, e.g., for filtration, drug release, and transport of reactants in responsive nano-reactors. Tuning permeability is thus of great importance since it enables selective barrier crossings in molecular transport. We develop a model of semi- flexible cross-linked polymer gel networks by means of extensive coarse-grained simulations and scaling theories. The gel system consists of randomly formed tetra- functional network regions and also bulk regions where the macromolecular cosolutes diffuse in both regions, enabling a quantitative study of partitioning, diffusivity, and permeability. The gel undergoes a sharp volume transition upon changing inter- and intra-particle interactions, yielding a rich topology of the partitioning phase landscape which is highly correlated with the cosolute diffusivity. Moreover, we find that resultant permeability is largely maximized or minimized at an optimal gel density and inter-particle couplings between the networks and the cosolutes. This nontrivial phenomenon is triggered by a competition between partitioning and diffusion, resulting in a large anti-correlation. It is revealed that permeability can be highly selective by tuning the coupling interactions and the solvent quality. By applying external driving forces, we show this selectiveness of permeability beyond the linear response regime based on the solution-diffusion model. Finally we present scaling theories for partitioning, diffusion and thus permeability in crowded systems. Permeability (electromagnetism) ; Diffusion ; Chemistry ; Thermodynamics ; Physics ; Membrane Surfactants and Colloidal Systems ; Odor and Emission Control Technologies ; Membrane Separation and Gas Transport
Authors: Elliot J. Carr | Giuseppe Pontrelli
Source: Mathematical Biosciences (preprint, 2019-06-18)
Field: Chemistry — Organic Chemistry

Drug delivery from microcapsules: How can we estimate the release time? Drug delivery ; Diffusion ; Pharmaceutics ; A priori and a posteriori ; Capsule ; Computer science ; Biological system ; Materials science ; Applied mathematics ; Mathematics ; Statistical physics ; Nanotechnology ; Physics ; Thermodynamics ; Medicine Surfactants and Colloidal Systems ; Protein purification and stability ; Advanced Drug Delivery Systems
Authors: David Léonce Kouadio | Adjoavi Colette Djassou | Akissi Lydie Chantal Koffi | Karim Sory Traoré
Source: International Journal of Engineering and Applied Sciences (IJEAS) (article, 2019-10-31)
Field: Materials Science — General Materials Science

Development of materials for environmental pollution control from cocoa pod shells To eliminate pollutants efficiently and at a lower cost, research is focused on the use of agricultural waste as a pollution control material. This work involves the analysis of the physical and chemical parameters of raw carbon from cocoa pod shells. The cocoa shells were crushed using Retsch SK100 brand shredders and sieved from Retsch type sieves to retain only particles with diameters between 0.5mm and 1mm. Pyrolysis was carried out at 400, 450, 500 and 550C in a Nabatherm 30-3300C muffle furnace. Analysis of the results indicates pyrolysis yields of less than 50% and ash rates varying from 15% to 17.2%. The porosity study showed that carbons developed a heterogeneous porosity with maximum iodine and methylene blue index values equal to 659mg/g and 104.56mg/g respectively and a specific area varying from 427.75m/g to 588.25m/g. These physical characteristics allowed to determine the best raw carbons. The modeling of the basic and acid dye adsorption kinetics follows the intra-particle diffusion model. The equilibrium time obtained is 60min. Point of delivery ; Environmental pollution ; Pollution ; Environmental science ; Engineering ; Environmental protection ; Botany ; Biology ; Ecology Material Properties and Applications ; Material Selection and Properties
Authors: И. Д. Трошкина | J. A OBRUCHNIKOVA | Оlga А. Veselova | S. Pestov
Source: PERIÓDICO TCHÊ QUÍMICA (article, 2019-01-20)
Field: Materials Science — General Materials Science

KINETICS OF POLYMER CARRIER IMPREGNATION BY TRIALKYLAMINE The immediacy of the problem under study is due to the lack of data on the kinetics of polymer carrier impregnation with extraction agents. The article is aimed at obtaining the kinetic characteristics of the impregnation of a polymeric macroporous carrier—a weakly acidic cation resin with carboxyl groups—with trialkylamine and its solutions in acetone. The integral kinetic curves of the extraction agent adsorption on the carrier were obtained. This allowed estimating the time of equilibrium by the limited solution volume method. This time was 25-30 hours, decreasing with the application of a dilution agent and with the increase in temperature. The kinetic impregnation characteristics were calculated by means of the pseudo-second-order, Elovich, and internal diffusion models. The pseudo-second-order model describes the experimental kinetic data with a high correlation degree (R2 0.995-0.997) and points out that interaction with two sorption centres possibly takes place with the adsorption of a single trialkylamine molecule. The impregnation rate constants via an extraction agent were calculated using all kinetic models. Based on the apparent activation energy magnitude (37±14 kJ/mol), it can be assumed that diffusion is the rate-limiting step of the impregnation process. This article can be useful for creating impregnates containing extraction agents of various classes. Diffusion ; Extraction (chemistry) ; Kinetic energy ; Kinetics ; Polymer ; Adsorption ; Sorption ; Reaction rate constant ; Activation energy ; Acetone ; Chemistry ; Materials science ; Analytical Chemistry (journal) ; Thermodynamics ; Physical chemistry ; Chromatography ; Organic chemistry Material Properties and Applications ; Polymer Synthesis and Characterization ; Adsorption, diffusion, and thermodynamic properties of materials
Authors: Ion Riza | Constantin Gheorghe Opran
Source: Materials science forum (article, 2019-06-01)
Field: Materials Science — General Materials Science

Methods and Special Functions Bessel and Kummer Applied in Composites Diffusion Modelling The oxygen diffusion is a natural phenomenon and a main factor during the atmospheric corrosion process. The phenomenon of oxygen diffusion takes place in the environment with different consequences: vital in medicine in relation with the oxygen diffusion in the blood, or negative in technical or industrial domains with catastrophic consequences due to corrosion. Diffusion modelling with applications for the analysis of the metal-composite interface, being subjected to corrosion in atmospheric environment for hybrid polymer structural composite products, is carried out with two remarkable equations: Fick’s second law or heat equation and the convective variant and the parabolic equation which introduces the diffusion coefficient in function of distance. In this paper we determine the solution of these equations using different mathematical methods. The state of oxygen concentration, modelled with partial derivatives, obtained theoretically, through oxides and metal layers, is experimentally validated in a practical case. Corrosion ; Diffusion ; Materials science ; Composite number ; Heat equation ; Diffusion equation ; Bessel function ; Oxygen ; Composite material ; Metallurgy ; Mechanics ; Thermodynamics ; Mathematical analysis ; Mathematics ; Physics Material Properties and Applications
Authors: Zonghuan Wang | Jun Yin
Source:  (article, 2019-06-10)
Field: Materials Science — Biomaterials

Experimental and Numerical Analyses on the Poly(Lactide-Co-Glycolide) Hollow Fiber Membranes Abstract The hollow fiber membranes (HFMs) were widely used as tissue engineering scaffold. The efficacy of the HFMs were affected by the porosity of the HFMs. In this study, the HFMs were prepared with dry-jet wet spinning method. In order to improve the performance of the HFMs, different spinning parameters were applied to systematically investigating the effects of the fabrication conditions on the porosity of the HFMs. A 1-D diffusion model was set to numerically study the volume fraction distribution along the wall thickness. The porosity of the HFMs show a significant decrease in the porosity as the dope concentration increases. The morphology analyses showed that a higher dope concentration leads to a denser porous structure which result in a lower porosity. The results were discussed based on the phase inversion process and the 1-D model was built to numerically analyze the polymer volume fraction distribution in the HFMs cross section. This study can help to better understand the effects of the different fabrication conditions on the morphology of the HFMs. Materials science ; Porosity ; Spinning ; Volume fraction ; Fabrication ; Membrane ; Phase inversion ; Hollow fiber membrane ; Composite material ; Fiber Electrospun Nanofibers in Biomedical Applications ; Advanced Cellulose Research Studies ; Membrane Separation Technologies