jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Maresa Vivien Kempin | Anja Drews
Source: Membranes (article, 2021-11-10)
Field: Materials Science — Materials Chemistry

Organic Solvent Nanofiltration of Water-in-Oil Pickering Emulsions—What Influences Permeability? Pickering emulsions (PEs) have received increasing interest for their application in catalytic multiphase reactions. Organic solvent nanofiltration of PEs was shown to be a promising procedure for efficient and effective catalyst recycling. In this work, a systematic parameter study to identify the main influencing parameters on PE filtration was conducted for a large variety of PE compositions for the first time. In addition to temperature, only the type of organic solvent significantly influenced the filtration performance, which could be mathematically modeled via a combination of the solution-diffusion and the resistance in the series model. Particle type and concentration, dispersed phase fraction and the presence of reaction (by-)products did not show any significant impact on the permeability. The stirrer speed only became important when emulsions stabilized by particles without the tendency to form 3D network structures were filtered in long-term filtration experiments. These results pave the way towards the application of PE membrane filtration for catalyst recovery in continuous liquid/liquid multiphase reactions and enable broad operation windows. As the mechanical separation of PEs was shown to be a very robust process, the emulsion composition can now be tuned to meet the needs of the reaction without any (significant) loss in filtration performance. Nanofiltration ; Pickering emulsion ; Permeability (electromagnetism) ; Organic solvent ; Solvent ; Chemical engineering ; Petroleum engineering ; Materials science ; Emulsion ; Chemistry ; Organic chemistry ; Membrane ; Geology ; Engineering Pickering emulsions and particle stabilization ; Enhanced Oil Recovery Techniques ; Advanced Polymer Synthesis and Characterization
Authors: Hamid Zahedi | Nahid Farzi | Nasser Golestani
Source: Journal of Engineering and Applied Science (article, 2021-11-18)
Field: Materials Science — Materials Chemistry

Systematic kinetic study of magnesium production using magnesium oxide and carbonic materials at different temperatures Abstract The main goal of this study was to determine the industrially best reductant for reduction of magnesium oxide to magnesium with wood charcoal and petroleum coke (petcoke) each in molar ratio 1:1 and 1:2 (oxidant:reductant) at high temperatures. In this study, a new and reliable combination of mathematical modeling and discrete numerical optimization theory by presenting 18 “mathematical filters” not relying only on statistical quantities of fitting (contrary to many similar researches) was introduced. The purpose of these filters was the determination of correct kinetic equation and therefore, the corresponding rate coefficient from among 18 equations most used at present in the challenging field of solid state chemical kinetics. With assistance of a new and fundamental mathematical function and the obtained values of rate coefficients, the function of rate coefficient in temperature was attained. The activation energy was then calculated as a function of temperature using the general definition of activation energy and the determined function for rate coefficient. The comparison between different reducing agents in the different conditions and with relevant previous study was accomplished to determine the best reducing agent from industry standpoint. Also, the areas under experimental data were calculated numerically and utilized for method validation and comparison. It turned out finally that relying only on fitting quantities in the solid state chemical kinetics can readily lead to wrong conclusions about the correct kinetic equation and about the most suitable reducing agent. It is obvious that the erroneous calculations and wrong decisions in the laboratory scale become significant and paramount in industry and this reveals the significance of rigorous mathematical analysis. Graphical abstract Magnesium ; Thermodynamics ; Activation energy ; Kinetic energy ; Function (biology) ; Reaction rate ; Chemistry ; Applied mathematics ; Materials science ; Mathematics ; Physical chemistry ; Physics ; Organic chemistry Thermal and Kinetic Analysis ; Magnesium Oxide Properties and Applications ; Catalysis and Hydrodesulfurization Studies
Authors: Yaseen Ayub | Rabia Nazir | Muhammad Ibrar | Muhammad Arsalan | Muhammad Raza Shah | Qaisar Ahmad | Muhammad Shabbir Shakir
Source: Environmental Science Pollution Research and Management (article, 2021-01-01)
Field: Chemistry — Inorganic Chemistry

Calotropis gigentea Mediated Cr2O3 Nanoparticles Synthesis and Application in Removal of Microbial and Endocrine Disrupting Chemicals Plant mediated Cr2O3 (GCO) nanoparticles (85.72nm) were synthesized at room temperature using ethanolic leaves' extract of Calotropis gigentea. The nanoparticles obtained were characterized using FTIR, SEM/ EDX, AFM and powder XRD to get insight into morphology, particle size and phase. The synthesized GCO were checked for their efficacy towards the removal of Endocrine Disrupting Chemicals (EDC i.e. an azo dye, pyrethroid insecticide, phthalate) and pathogenic bacteria (Staphylococcus aureus). The results showed high adsorption capacities (296.11, 87.92 and 231.3 mg g -1 ) for the three contaminants i.e. Direct Yellow 24, Bifenthrin and Dioctyl phthalate, respectively in just 15-20min at room temperature. GCO also showed good bacteriostatic activity and is able to remove 80.9% of the microbes in simulated water samples. Hence, it can be safely concluded that the prepared GCO is a good material for effective treatment of multi-natured organic contaminants as well as microbes without requiring any stringent experimental conditions. Endocrine system ; Chemistry ; Environmental chemistry ; Nanoparticle ; Biotechnology ; Nanotechnology ; Biology ; Biochemistry ; Materials science ; Hormone Pigment Synthesis and Properties ; Nanoparticles: synthesis and applications ; Magnesium Oxide Properties and Applications
Authors: Bo Fang | Jian‐Min Yan | Dan Chang | Jinli Piao | Kit Ming | Qiao Du | Ping Gao | Yang Chai | Xiaoming Tao
Source: Research Square (preprint, 2021-12-08)
Field: Materials Science — Polymers and Plastics

Scalable production of ultrafine polyaniline fibres for tactile organic electrochemical transistors Abstract The development of continuous conducting polymer fibres is essential for applications ranging from advanced fibrous devices to frontier fabric electronics. The use of continuous conducting polymer fibres requires a small diameter to maximize their electroactive surfaces, microstructural orientations, and mechanical strengths. However, regularly used wet spinning techniques have rarely achieved this goal due primarily to the insufficient slenderization of rapidly solidified conducting polymer molecules in poor solvents. Here we report a good solvent exchange strategy to wet spin the ultrafine polyaniline fibres at the large scale. The slow diffusion between good solvents distinctly decreases the viscosity of gel protofibers, which undergo an impressive drawing ratio. The continuously collected polyaniline fibres have a previously unattained diameter below 5 µm, high energy and charge storage capacities, and favorable mechanical performance. We demonstrated an ultrathin all-solid organic electrochemical transistor based on ultrafine polyaniline fibres, which substantially amplified microampere drain-source electrical signals with less one volt driving voltage and effectively operated as a tactile sensor detecting pressure and friction forces at different levels. The aggressive electronical and electrochemical merits of ultrafine polyaniline fibres and their great potentials to prepare on industrial scale offer new opportunities for high-performance soft electronics and large-area electronic textiles. Polyaniline ; Materials science ; Electrochemistry ; Scalability ; Production (economics) ; Nanotechnology ; Transistor ; Electrode ; Computer science ; Composite material ; Electrical engineering ; Polymer ; Chemistry ; Engineering ; Voltage Conducting polymers and applications ; Advanced Sensor and Energy Harvesting Materials ; Organic Electronics and Photovoltaics
Authors: Khaliq Ahmed | Periasamy Vijay | Moses O. Tadé | Amirpiran Amiri | Zongping Shao | K. Föger
Source: Journal of Energy and Power Technology (article, 2021-01-17)
Field: Materials Science — Materials Chemistry

SOFC Stack and System Modeling, Fault Diagnosis and Control This report is an account of research and development activities undertaken by the Centre for Process Systems Computations, Department of Chemical Engineering at Curtin University, Western Australia in the area of solid oxide fuel cells. The focus of work of the group included 1)effect of cell macrostructure and microstructure on electrochemical performance with a view to optimise both macro- and micro-structure 2) electrochemistry modeling for simulating electrochemical performance 3) internal reforming aspects impacting performance at cell/stack and system levels 4) system level modeling investigating cell internal profiles (temperature, gas composition), homogeneity improvement, thermal management, anode recycle, fuel diversity, oxygen quality, and 5) monitoring for diagnostics, optimisation and control. The report summarizes work done over a period of 15 years and highlights areas of research gaps and future directions for research in the path to mass-scale commercialisation of the solid oxide fuel cell technology. Solid oxide fuel cell ; Stack (abstract data type) ; Anode ; Process engineering ; Work (physics) ; Engineering ; Computer science ; Mechanical engineering ; Materials science ; Chemistry ; Electrode Advancements in Solid Oxide Fuel Cells ; Electronic and Structural Properties of Oxides ; Catalysis and Oxidation Reactions
Authors: Naima Bayou | Hamid Aït-Amar | Samir Belkhiri | Zohra Bouhila | Fatima Houhoune | Sihem Khemaissia | Tarek Azli
Source: Comptes Rendus Chimie (article, 2021-10-15)
Field: Chemistry — Inorganic Chemistry

Equilibrium, isotherms and kinetic studies of uranium sorption onto AlPO <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mrow/> <mml:mn>4</mml:mn> </mml:msub> </mml:math> -5 and SAPO-5 materials The present work deals with the investigation of the use of the elaborated aluminophosphate (AlPO <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mrow/> <mml:mn>4</mml:mn> </mml:msub> </mml:math> -5) and silico-aluminophosphate (SAPO-5) materials, in uranium sorption from aqueous solution and real effluents obtained from Nuclear Research Center of Draria, Algiers, Algeria. The surface charge and acidic–basic character of AlPO <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mrow/> <mml:mn>4</mml:mn> </mml:msub> </mml:math> -5 and SAPO-5 is investigated by the determination of point of zero charge. Batch adsorption experimental studies are carried out to evaluate the influence of initial uranium concentration, final solution pH, contact time, solid-to-liquid ratio and temperature. A maximum adsorption capacity of 61.96 and 74.10 mg/g was obtained for AlPO <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mrow/> <mml:mn>4</mml:mn> </mml:msub> </mml:math> -5 and SAPO-5 respectively, at pH 7 with an adsorbent ratio of 0.1/150 g/ml and an equilibrium time of 120 min. Kinetic models (pseudo-first order, pseudo-second order and Weber–Morris) are applied to find the mechanism for the removal of uranium ions, experimental data are analyzed by equilibrium models (Langmuir, Freundlich, Dubinin–Radushkevich and Temkin). Modeling sorption results show that uranium sorption is a chemical and endothermic process. The results showed that AlPO <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mrow/> <mml:mn>4</mml:mn> </mml:msub> </mml:math> -5 and SAPO-5 are effective materials for the removal of uranium (VI) ions. Sorption ; Uranium ; Chemistry ; Materials science ; Physical chemistry ; Adsorption ; Metallurgy Radioactive element chemistry and processing ; Chemical Synthesis and Characterization ; Extraction and Separation Processes
Authors: M.R. Manafov | G.S. Aliyev | A.I. Rustamova | V.I. Kerimli
Source: Azerbaijan Chemical Journal (article, 2021-06-29)
Field: Chemistry — Analytical Chemistry

ANALYSIS OF THE CURRENT STATE OF RESEARCHES OF THE DEPOSITION OF ASPHALT-RESINOUS SUBSTANCES, PARAFFIN, AND MODELING METHODS. REVIEW PART II: WAX DEPOSITION The mechanism of paraffin formation in transport pipes is briefly discussed. A kinetic model of the formation and wax deposition from oil is proposed. Comparison of the model with the available experimental data gave satisfactory results. The review considers software tools for modeling the wax deposition process. It is noted that the simulation results are not always applicable to real field cases. For a more reliable interpretation, the scaling effect must be taken into account. In the work various technologies for wax removal are considered Wax ; Deposition (geology) ; Scaling ; Asphalt ; Paraffin wax ; Petroleum engineering ; Process (computing) ; Process engineering ; Environmental science ; Computer science ; Materials science ; Chemical engineering ; Chemistry ; Engineering ; Geology ; Composite material ; Mathematics Petroleum Processing and Analysis ; Heat transfer and supercritical fluids ; Enhanced Oil Recovery Techniques
Authors: Mohammed Danouche | Hicham El Arroussi | Naïma El Ghachtouli
Source: Research Square (preprint, 2021-05-03)
Field: Chemistry — Analytical Chemistry

Bioremoval mechanisms of azo dye Acid Red 14 using Wickerhamomyces anomalus yeast strain as a natural biosorbent Yeast ; Strain (injury) ; Chemistry ; Food science ; Microbiology ; Biochemistry ; Biology Dye analysis and toxicity ; Enzyme-mediated dye degradation ; Adsorption and biosorption for pollutant removal
Authors: Xiaoqin Nie | Faqin Dong | Mingxue Liu | Wencai Cheng | Congcong Ding | Liang Bian | Shiyong Sun
Source: Minerals (article, 2021-10-09)
Field: Chemistry — Inorganic Chemistry

Bonding Behavior and Mechanism of U(VI) by Chemically Modified Deinococcus radiodurans The goal of this study is to understand the role of various functional groups on the cell surface when the microorganisms are exposed to uranium (U(VI)). The biomass of Deinococcus radiodurans was subjected to chemical treatments to modify the carboxyl (-C=O), amino (-NH2), phosphate (-PO2−), and hydroxyl (-OH) groups, as well as the lipid fraction. The behavior and process of U(VI) biosorption by Deinococcus radiodurans were ascertained, followed by scanning electron microscopy (SEM) combined with energy disperse spectroscopy (EDS) and Fourier transform infrared spectroscopy (FTIR) analyses. Carboxyl esterification and amino methylation deteriorated the removal efficiency by 8.0% and 15.5%, respectively, while lipid extraction, phosphate esterification, and hydroxyl methylation improved the removal efficiency by 11.7%, 8.7%, and 4.1%, respectively. The kinetic results revealed that uranium biosorption behavior by the raw and chemically modified biomass fitted well with the model of pseudo-second-order kinetic (R2 = 0.9949~0.9998). FTIR and SEM-EDS indicated that uranium initially bound with the raw and chemically modified Deinococcus radiodurans, which was probably controlled by ion exchange at the first stage, followed by complexation with the -C=O and -NH2 groups, which especially prefer to bond with P and O atoms on the -PO2− group. Deinococcus radiodurans ; Fourier transform infrared spectroscopy ; Biosorption ; Nuclear chemistry ; Chemistry ; Uranium ; Adsorption ; Organic chemistry ; Materials science ; Chemical engineering ; Sorption ; Biochemistry ; DNA Radioactive element chemistry and processing ; Metal Extraction and Bioleaching ; Geochemistry and Elemental Analysis
Authors: Luigi Catacuzzeno | Fabio Franciolini | Francisco Bezanilla | Bob Eisenberg
Source: bioRxiv (Cold Spring Harbor Laboratory) (preprint, 2021-01-13)
Field: Chemistry — Electrochemistry

Gating current noise produced by Brownian models of a voltage sensor Abstract The activation of voltage-dependent ion channels is associated with the movement gating charges, that give rise to gating currents. Although gating currents originating from a single channel are too small to be detected, analysis of the fluctuations of macroscopic gating currents originating from a population of channels can make a good guess of their magnitude. The analysis of experimental gating current fluctuations, when interpreted in terms of a Markov model of channel activation, are in accordance with the presence of a main step along the activation pathway carrying 2.3-2.4 e 0 of charge. To give a physical interpretation to these results and to relate them to the known atomic structure of the voltage sensor domain, we employed a Brownian model of voltage-dependent gating that we recently developed using structural information and applying the laws of electrodynamics. The model was capable to reproduce gating currents and gating current fluctuations essentially similar to those experimentally observed. The detailed study of this model output, also performed by making several simplifications aimed at understanding the basic dependencies of the gating current fluctuations, suggests that in real ion channels the voltage sensor does not move in a fully Markovian regimen due to the relatively low (&lt;5 kT) energy barriers separating successive intermediate states. As a consequence, the simultaneous jump of multiple gating charges through the gating pore becomes frequent, and this occurrence is at the origin of the relatively high single-step charge detected by assuming Markovian behavior. Gating ; Physics ; Voltage ; Markov process ; Channel (broadcasting) ; Noise (video) ; Current (fluid) ; Markov chain ; Statistical physics ; Quantum mechanics ; Computer science ; Electrical engineering ; Mathematics ; Engineering Electrochemical Analysis and Applications ; stochastic dynamics and bifurcation ; Neural dynamics and brain function
Authors: Tadashi Kasuya | A. Toshimitsu Yokobori | Go Ozeki | Toshihito Ohmi | Manabu Enoki
Source: ISIJ International (article, 2021-01-13)
Field: Materials Science — Metals and Alloys

Modelling of Hydrogen Diffusion in a Weld Cold Cracking Test: Part 2, Numerical Calculations The purpose of this work is to compare the numerical calculation results of the hydrogen diffusion with the experimental results. We firstly conducted a y groove weld cracking test using 980 MPa grade steel and 780 MPa grade welding consumable to observe HAZ cracking. Next, we showed the present diffusion equation and the procedure to determine the physical properties for the calculations such as stress-strain curve, and using the apparent diffusion coefficient and the boundary condition obtained in the companion paper, we conducted the numerical calculations for the two cases, that is, the under-match case (980 MPa grade steel and 780 MPa grade welding consumable) and the even-match case (780 MPa grade steel and 780 MPa grade welding consumable). The calculation results of the under-match case show that hydrogen tends to accumulate in the stress concentration area of both the HAZ and the weld metal, which indicates crack may occur in both the HAZ and the weld metal. The results of the even-match case show not only the hydrogen accumulation around the stress concentration area but also high hydrogen concentration in the weld metal, which indicates crack may occur in the weld metal. Calculation results for both of the cases fairly agree with the experiments. Cracking ; Hydrogen ; Diffusion ; Materials science ; Welding ; Metallurgy ; Mechanics ; Structural engineering ; Forensic engineering ; Composite material ; Thermodynamics ; Engineering ; Chemistry ; Physics Hydrogen embrittlement and corrosion behaviors in metals ; Fatigue and fracture mechanics ; Welding Techniques and Residual Stresses
Authors: R. Sridevi | J. Charles Pravin
Source: 3C Tecnología_Glosas de innovación aplicadas a la pyme (article, 2021-11-30)
Field: Materials Science — Materials Chemistry

Potential and drain current simulation of a symmetric double gated Molybdenum Disulfide (MoS2) transistor As the scaling of silicon MOSFET reaches its physical limit, research efforts have been made in exploring alternative devices. In this paper, we have examined the enhanced drain current, electrostatic potential, mobility, and electric field for a symmetric structure of Double gated Molybdenum Disulfide (MoS 2 ) transistor. The performance of the device has been simulated using Technology Computer-Aided Design (TCAD) simulation tool. The above mentioned comparison model of drain current built by use of symmetric Double gated MoS 2 transistor has shown superior performances when compared with that of Silicon transistor. There is an enhancement of 0.1 A in its drain current and the mobility is 50 higher than the silicon based transistor, under the condition that this device has the same geometry. It was performed by incorporating the quantum mechanical effects in molybdenum disulfide (MoS 2 ) based transistor. Due to its high performance in low power operating voltages, MoS 2 transistor will be suitable for low power applications. Molybdenum disulfide ; Molybdenum ; Transistor ; Disulfide bond ; Current (fluid) ; Materials science ; Optoelectronics ; Chemistry ; Electrical engineering ; Inorganic chemistry ; Engineering ; Voltage ; Metallurgy 2D Materials and Applications ; Semiconductor materials and interfaces ; Advanced Memory and Neural Computing
Authors: Alina V. Dvornichenko | Vasyl O. Kharchenko | Dmitrii O. Kharchenko
Source: Beilstein Journal of Nanotechnology (article, 2021-07-13)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Electromigration-induced formation of percolating adsorbate islands during condensation from the gaseous phase: a computational study We provide a computational study of a change in the morphology of a growing thin film during condensation caused by electromigration effects. It will be shown, that separated circular adsorbate islands, realized in an isotropic system, become elongated in the direction of the applied electrical field. We discuss the dependence of the critical value of the strength of the applied electrical field, responsible for the formation of percolating adsorbate islands, on main control parameters. This study provides insight into details of electromigration effects during the self-organization of adatoms into percolating adsorbate islands during condensation from the gaseous phase. We will show that the elongated morphology of adsorbate islands remains stable if the electric field is turned off. Electromigration ; Condensation ; Electric field ; Isotropy ; Materials science ; Chemical physics ; Phase (matter) ; Condensed matter physics ; Morphology (biology) ; Thin film ; Field (mathematics) ; Nanotechnology ; Composite material ; Chemistry ; Thermodynamics ; Optics ; Physics ; Geology Copper Interconnects and Reliability ; Force Microscopy Techniques and Applications ; Molecular Junctions and Nanostructures