jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Tong Li | Shuangwei Wang | Jinqiang Gao | Rui-Qiang Wang | Guifeng Gao | Guangming Ren | Shengnan Na | Mei Hong | Shihe Yang
Source: Molecules (article, 2024-03-22)
Field: Chemistry — Inorganic Chemistry

Spherical Binderless 4A/5A Zeolite Assemblies: Synthesis, Characterization, and Adsorbent Applications Zeolite microspheres have been successfully applied in commercial-scale separators such as oxygen concentrators. However, further enhancement of their applications is hampered by the post-synthetic shaping process that formulates the zeolite powder into packing-sized spherical bodies with various binders leading to active site blockage and suboptimal performance. Herein, binderless zeolite microspheres with a tunable broad size range from 2 µm to 500 µm have been developed with high crystallinity, sphericity over 92%, monodispersity with a coefficient of variation (CV) less than 5%, and hierarchical pore architecture. Combining precursor impregnation and steam-assisted crystallization (SAC), mesoporous silica microspheres with a wide size range could be successfully transformed into zeolite. For preserved size and spherical morphology, a judicious selection of the synthesis conditions is crucial to ensure a pure phase, high crystallinity, and hierarchical architecture. For the sub-2-µm zeolite microsphere, low-temperature prolonged aging was important so as to suppress external zeolization that led to a large, single macroporous crystal. For the large 500 µm sphere, ultrasound pretreatment and vacuum impregnation were crucial and facilitated spatially uniform gel matrix dispersion and homogenous crystallization. The obtained zeolite 5A microspheres exhibited excellent air separation performance, while the 4A microspheres displayed ammonium removal capabilities. This work provides a general strategy to overcome the existing limitations in fabricating binder-free technical bodies of zeolites for various applications. Zeolite ; Materials science ; Crystallinity ; Chemical engineering ; Crystallization ; Mesoporous material ; Adsorption ; Sphericity ; Nanotechnology ; Composite material ; Organic chemistry ; Chemistry ; Catalysis Zeolite Catalysis and Synthesis ; Covalent Organic Framework Applications ; Mesoporous Materials and Catalysis
Authors: Seokwoo Kim | Joohoon Kim | Kyungtae Kim | Minsu Jeong | Junsuk Rho
Source: arXiv (Cornell University) (preprint, 2024-06-17)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Anti-aliased metasurfaces beyond the Nyquist limit Sampling is a pivotal element in the design of metasurfaces, enabling a broad spectrum of applications. Despite its flexibility, sampling can result in reduced efficiency and unintended diffractions, which are more pronounced at high numerical aperture or shorter wavelengths, e.g. ultraviolet spectrum. Prevailing metasurface research has often relied on the conventional Nyquist sampling theorem to assess sampling appropriateness, however, our findings reveal that the Nyquist criterion is insufficient for preventing the diffractive distortion. Specifically, we find that the performance of a metasurface is significantly correlated to the geometric relationship between the spectrum morphology and sampling lattice. Based on lattice-based diffraction analysis, we demonstrate several anti-aliasing strategies from visible to ultraviolet regimes. These approaches significantly reduce aliasing phenomena occurring in high numerical aperture metasurfaces. Nyquist frequency ; Limit (mathematics) ; Nyquist–Shannon sampling theorem ; Computer science ; Business ; Physics ; Mathematics ; Telecommunications ; Computer vision ; Mathematical analysis ; Bandwidth (computing) Metamaterials and Metasurfaces Applications ; Advanced Antenna and Metasurface Technologies ; Electromagnetic Scattering and Analysis
Authors: Levi D. Palmer | Wonseok Lee | Chung‐Li Dong | Ru‐Shi Liu | Nianqiang Wu | Scott K. Cushing
Source: ACS Nano (article, 2024-03-18)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Determining Quasi-Equilibrium Electron and Hole Distributions of Plasmonic Photocatalysts Using Photomodulated X-ray Absorption Spectroscopy Most photocatalytic and photovoltaic devices operate under broadband, constant illumination. Electron and hole dynamics in these devices, however, are usually measured by using ultrafast pulsed lasers in a narrow wavelength range. In this work, we use excited-state X-ray theory originally developed for transient X-ray experiments to study steady-state photomodulated X-ray spectra. We use this method to attempt to extract electron and hole distributions from spectra collected at a nontime-resolved synchrotron beamline. A set of plasmonic metal core-shell nanoparticles is designed as the control experiment because they can systematically isolate photothermal, hot electron, and thermalized electron-hole pairs in a TiO<sub>2</sub> shell. Steady-state changes in the Ti L<sub>2,3</sub> edge are measured with and without continuous-wave illumination of the nanoparticle's localized surface plasmon resonance. The results suggest that within error the quasi-equilibrium carrier distribution can be determined even from relatively noisy data with mixed excited-state phenomena. Just as importantly, the theoretical analysis of noisy data is used to provide guidelines for the beamline development of photomodulated steady-state spectroscopy. Plasmon ; Absorption (acoustics) ; Materials science ; Electron ; Spectroscopy ; X-ray ; X-ray spectroscopy ; Absorption spectroscopy ; X-ray absorption spectroscopy ; Optoelectronics ; Analytical Chemistry (journal) ; Atomic physics ; Molecular physics ; Optics ; Chemistry ; Physics Gold and Silver Nanoparticles Synthesis and Applications ; Advanced Photocatalysis Techniques ; Ga2O3 and related materials
Authors: J. Prażuch | Michał Pyzalski | Daniel Fernández González | Tomasz Brylewski
Source: Materials (article, 2024-08-01)
Field: Materials Science — Materials Chemistry

Physicochemical Properties of (La,Sr)CoO3 Thick Films on Fe-25Cr Steel under Exposure to SOFC Cathode Operating Conditions La<sub>0.6</sub>Sr<sub>0.4</sub>CoO<sub>3</sub> (LSC) coatings with a thickness of 50-100 µm were deposited on Fe-25Cr ferritic stainless steel (DIN 50049) via screen printing. The required suspension had been prepared using fine LSC powders synthesised using EDTA gel processes. In its bulk form, the LSC consisted entirely of the rhombohedral phase with space group <i>R-3c</i>, and it exhibited high electrical conductivity (~144 S·cm<sup>-1</sup>). LSC-coated steel was oxidised in air at 1073 K, i.e., under conditions corresponding to SOFC cathode operation, for times of up to 144 h. The in situ electrical resistance of the steel/La<sub>0.6</sub>Sr<sub>0.4</sub>CoO<sub>3</sub> layered system during oxidation was measured. The products formed on the samples after the oxidation reaction resulting from exposure to the corrosive medium were investigated using XRD, SEM-EDS, and TEM-SAD. The microstructural, nanostructural, phase, and chemical analysis of films was performed with a focus on the film/substrate interface. It was determined that the LSC coating interacts with the oxidised steel in the applied conditions, and a multi-layer interfacial zone is formed. Detailed TEM-SAD observations indicated the formation of a main layer consisting of SrCrO<sub>4</sub>, which was the reaction product of (La,Sr)CoO<sub>3</sub>, and the Cr<sub>2</sub>O<sub>3</sub> scale formed on the metal surface. The formation of the SrCrO<sub>4</sub> phase resulted in improved electrical conductivity of the investigated metal/ceramics layered composite material, as demonstrated by the low area-specific resistance values of 5 mΩ·cm<sup>2</sup>, thus making it potentially useful as a SOFC interconnect material operating at the tested temperature. In addition, the evaporation rate of chromium measured for the uncoated steel and the steel/La<sub>0.6</sub>Sr<sub>0.4</sub>CoO<sub>3</sub> layered system likewise indicates that the coating is capable of acting as an effective barrier against the formation of volatile compounds of chromium. Materials science ; Cathode ; Metallurgy ; Composite material ; Chemistry Advancements in Solid Oxide Fuel Cells ; Electronic and Structural Properties of Oxides ; Semiconductor materials and devices
Authors: Abhishek Nayak | Vaishnavi P Karkare | Kapil Sadani | Harshini Dasari | A. Sivasamy | Nethaji Sundarabal
Source: Environmental Science and Pollution Research (article, 2024-03-25)
Field: Chemistry — Analytical Chemistry

Asphaltene-derived nanocomposites for the removal of emerging pollutants and its antimicrobial effects: batch and continuous column studies Emerging contaminants are diverse ecotoxic materials requiring unique treatment for removal. Asphaltenes are environmentally hazardous carbon-rich solid waste product of the petroleum industry. In the current work, asphaltene-derived activated carbon (AC) was loaded with silver (Ag/AC) and used to remove amoxicillin (AMX) and tetracycline (TC) from aqueous phase. The prepared Ag/AC was characterised using FESEM, FTIR, XRD and surface area analysis. The FESEM micrographs confirmed the spherical silver nanoparticle-laden porous AC, and the BET surface area was found to be 213 m<sup>2</sup>/g. Batch adsorption studies were performed, and the equilibrium data were fit into adsorption isotherm and kinetic models. The Ag/AC exhibited superior monolayer adsorption capacity of 1012 mg/g and 770 mg/g for AMX and TC, respectively. The continuous column studies were also performed to evaluate the breakthrough parameters. Furthermore, the antimicrobial activity of the adsorbent was evaluated using zone of inhibition studies. Ag/AC was found to have an 8-mm-diameter zone of microbial inhibition. The obtained results showed that Ag/AC was a promising material for the removal of antibiotics and inhibition of resistance-developed mutated microbes in effluent water. Adsorption ; Asphaltene ; Activated carbon ; Nanocomposite ; Chemical engineering ; Effluent ; Aqueous solution ; Fourier transform infrared spectroscopy ; Materials science ; Nuclear chemistry ; Monolayer ; Chemistry ; Chromatography ; Organic chemistry ; Nanotechnology ; Waste management Petroleum Processing and Analysis ; Adsorption and biosorption for pollutant removal ; Electrochemical Analysis and Applications
Authors: Ping Chen | Luc R. Van Loon | Steffen Koch | Peter Alt‐Epping | Tobias Reich | Sergey V. Churakov
Source: Applied Clay Science (article, 2024-03-07)
Field: Chemistry — Inorganic Chemistry

Reactive transport modeling of diffusive mobility and retention of TcO4− in Opalinus Clay Tc-99 has drawn widespread concern because of its long half-life, high fission yield and high mobility in research of radioactive waste disposal and environmental remediation. TcO4− through-diffusion experiments in Opalinus Clay (OPA) were performed under air and under argon No noticeable Tc-breakthrough was observed for over one year while the total Tc concentration in the source reservoir was steadily decreasing under both air and argon atmosphere. The total Tc activity distribution in the clay sample along the diffusion direction was obtained by slicing the OPA clay samples retrieved from the diffusion cells, using the abrasive peeling technique. In the case of diffusion under air atmosphere, almost no Tc was measured in that part of the sample close to source reservoir, while much more Tc was measured under argon atmosphere. A reasonable explanation for this observation is that the reductive retention of Tc plays a significant role during transport. A reactive transport model was constructed to simulate the diffusion process whereby the diffusion of Tc was coupled with redox reactions. Even though reduction of TcO4− by aqueous Fe2+ is thermodynamically feasible, it was not observed in the experiment. Furthermore, Fe2+ associated with solid phase was demonstrated to be more active than aqueous Fe2+. Therefore, surface complexation redox reaction was proposed. Dissolution rate of pyrite, equilibrium constant and diffusion coefficient of TcO4− were considered as possible factors controlling the redox reaction. Modeling results showed that TcO4− diffused into the clay and was partially reduced into surface complexed Tc(IV) by pyrite. When TcO4− transported under air atmosphere, O2 competitively consumed Fe2+ and pyrite, resulting in no Tc immobilization in the related zone. Chemistry ; Geology ; Chemical engineering ; Environmental chemistry ; Mineralogy ; Environmental science Radioactive element chemistry and processing ; Groundwater flow and contamination studies ; Chemical Synthesis and Characterization
Authors: Yuanquan Yang | Jiamin Han | Runqing Liu
Source: MRS Communications (article, 2024-01-26)
Field: Materials Science — Materials Chemistry

A method for determining the hydration degree of magnesium potassium phosphate cements Magnesium ; Dissolution ; Materials science ; Potassium phosphate ; Degree (music) ; Potassium ; Thermodynamics ; Log-normal distribution ; Isothermal process ; Chemical engineering ; Phosphate ; Kinetics ; Mineralogy ; Metallurgy ; Chemistry ; Chromatography ; Mathematics ; Physics ; Biochemistry Magnesium Oxide Properties and Applications ; Multiferroics and related materials ; Layered Double Hydroxides Synthesis and Applications
Authors: M.I. Satayev | Abdugani Azimov | A. Brener | Nina Alekseyeva | Z. M. Shakiryanova
Source: Frontiers in Heat and Mass Transfer (article, 2024-01-01)
Field: Chemistry — Spectroscopy

Modeling of the Adsorption Allowing for the Changing Adsorbent Activity at Various Stages of the Process The goal of this work is, first of all, to construct a mathematical model of the mass transfer process in porous adsorption layers, taking into account the fact that in most cases the adsorption process is carried out in non-... | Find, read and cite all the research you need on Tech Science Press Adsorption ; Process (computing) ; Thermal fluids ; Materials science ; Chemical engineering ; Process engineering ; Process management ; Biochemical engineering ; Chemistry ; Thermodynamics ; Computer science ; Engineering ; Organic chemistry ; Heat transfer ; Physics Adsorption, diffusion, and thermodynamic properties of materials ; Water Quality Monitoring and Analysis ; Statistical and Computational Modeling
Authors: А. К. Кычкин | A. A. Gavrilieva | А.А. Кычкин | Irina G. Lukachevskaya | М. П. Лебедев
Source: Polymers (article, 2024-03-22)
Field: Materials Science — General Materials Science

The Initial Stage of Climatic Aging of Basalt-Reinforced and Glass-Reinforced Plastics in Extremely Cold Climates: Regularities Detailed analyses of the reasons for changes in the mechanical parameters of fiberglass exposed to different climatic zones have been made available in the literature; however, such detailed studies of basalt plastic do not yet exist. It is possible to make reasonable conclusions on the climatic resistance of reinforced plastics by monitoring the deformation-strength characteristics in combination with fractographic and DMA analyses of the solar- and shadow-exposed parts of the plastics; additionally, one can conduct analyses of the IR spectrum and the moisture sorbtion kinetics. As a starting point for the climatic aging of polymer composite materials, it is necessary to accept the time of exposure in which the maximum values of the elastic strength properties of polymeric materials are achieved. Based on the results of the DMA analysis, it was found that, unlike basalt-reinforced plastics (where the material is post-cured exclusively at the initial stage of the exposure), in glass-reinforced plastic, a process of destruction occurs. The formation of internal stresses in the material and their growth were determined through observing the duration of climatic exposure. The formation of closed porosity, depending on the duration of exposure, can be assessed using the values of the increase in the average moisture content. A set of experimental studies has established that glass-reinforced plastics are subject to greater destruction under the influence of a very cold climate than the basalt-reinforced plastic. Materials science ; Composite material ; Porosity ; Basalt ; Moisture ; Cold climate ; Polymer ; Frost (temperature) ; Geology Material Properties and Applications ; Structural mechanics and materials ; Aerospace, Electronics, Mathematical Modeling
Authors: Chaida Butumap Ngolong Ngwethe | Gervais Kounou Ndongo | Donald Raoul Tchuifon Tchuifon | Cyrille Ghislain Fotsop | Dave Sanchez Mouafo Dongmo | Urselin Roland Noumsi Foko | Lynda Nathalie Nkom Soue | Melea Charles Kede
Source: Sustainable Chemical Engineering (article, 2024-07-18)
Field: Chemistry — Analytical Chemistry

Regeneration and Reusability of Bleaching Earth as a Sustainable Material for Tartrazine Yellow (E102) Removal: Insights into Kinetic Mechanisms Anionic dyes, like tartrazine, have harmful effects on aquatic life and humans and therefore, their elimination from industrial effluents needs to be taken very seriously. The elimination of tartrazine yellow from wastewater resulted in the application of adsorption as an economical and effective treatment approach. The use of regenerated bleaching earth and regenerated bleaching earth modified with urea as adsorbents for tartrazine yellow from simulated wastewater served as the foundation for this study. The sorption process was run in batch mode with different process parameters. The Fourier transform infrared spectrophotometry (FTIR) and X-ray diffraction analyses of the adsorptive material demonstrated the existence of surface functional groups while scanning electron microscopy revealed a porous structure. At a pH of 3, with an adsorbent dosage of 50 mg and a dye concentration of 50 mg/L, the highest dye uptake was achieved with an adsorption efficiency of 48%. The models that best matched the kinetics were the pseudo-first-order, pseudo-second-order and Elovich (R2 &gt; 0.95) models. The dye fixation process took 140 minutes to reach adsorption equilibrium. The outcomes of the sorption study demonstrated competition between chemisorption and physisorption, and that bleaching earth can be successfully regenerated, and used as an efficient sorbent for eliminating tartrazine yellow in an aqueous solution. Tartrazine ; Reusability ; Regeneration (biology) ; Earth (classical element) ; Kinetic energy ; Chemistry ; Environmental science ; Computer science ; Biology ; Mathematics ; Physics ; Chromatography ; Cell biology Dye analysis and toxicity
Authors: Žiga Medoš | Marija Bešter‐Rogač | Epameinondas Leontidis | Joel Tellinghuisen
Source: Analytical Biochemistry (article, 2024-07-06)
Field: Chemistry — Physical and Theoretical Chemistry

Calibrating ITC instruments: Problems with weak base neutralization Modern isothermal titration calorimetry instruments give great precision, but for comparable accuracy they require chemical calibration. For the heat factor, one recommended process is HCl into the weak base TRIS. In studying this reaction with a VP-ITC and two Nano-ITCs, we have encountered some problems, most importantly a titrant volume shortfall Δv ≈ 0.3 μL, which we attribute to diffusive loss of HCl in the syringe tip. This interpretation is supported by a mathematical treatment of the diffusion problem. The effect was discovered through a variable-v protocol, which thus should be used to properly allow for it in any reaction that similarly approaches completion. We also find that the effects from carbonate contamination and from OH<sup>-</sup> from weak base hydrolysis can be more significant that previously thought. To facilitate proper weighting in the least-squares fitting of data, we have estimated data variance functions from replicate data. All three instruments have low-signal precision of σ ≈ 1 μJ; titrant volume uncertainty is a factor of ∼2 larger for the Nano-ITCs than for the VP-ITC. The final heat factors remain uncertain by more than the ∼1 % precision of the instruments and are unduly sensitive to the HCl concentration. Isothermal titration calorimetry ; Titration ; Calibration ; Chemistry ; Protocol (science) ; Base (topology) ; Diffusion ; Analytical Chemistry (journal) ; Inorganic chemistry ; Thermodynamics ; Physical chemistry ; Chromatography ; Mathematics ; Statistics ; Physics thermodynamics and calorimetric analyses ; Chemical and Physical Properties in Aqueous Solutions ; Field-Flow Fractionation Techniques
Authors: San To Chan | Eliot Fried
Source: PNAS Nexus (article, 2024-02-01)
Field: Materials Science — Materials Chemistry

Marangoni spreading on liquid substrates in new media art With the advent of new media art, artists have harnessed fluid dynamics to create captivating visual narratives. A striking technique known as dendritic painting employs mixtures of ink and isopropanol atop paint, yielding intricate tree-like patterns. To unravel the intricacies of that technique, we examine the spread of ink/alcohol droplets over liquid substrates with diverse rheological properties. On Newtonian substrates, the droplet size evolution exhibits two power laws, suggesting an underlying interplay between viscous and Marangoni forces. The leading edge of the droplet spreads as a precursor film with an exponent of 3/8, while its main body spreads with an exponent of 1/4. For a weakly shear-thinning acrylic resin substrate, the same power laws persist, but dendritic structures emerge, and the texture of the precursor film roughens. The observed roughness and growth exponents (3/4 and 3/5) suggest a connection to the quenched Kardar-Parisi-Zhang universality class, hinting at the existence of quenched disorder in the liquid substrate. Mixing the resin with acrylic paint renders it more viscous and shear-thinning, refining the dendrite edges and further roughening the precursor film. At larger paint concentrations, the substrate becomes a power-law fluid. The roughness and growth exponents then approach 1/2 and 3/4, respectively, deviating from known universality classes. The ensuing structures have a fractal dimension of 1.68, characteristic of diffusion-limited aggregation. These findings underscore how the nonlinear rheological properties of the liquid substrate, coupled with the Laplacian nature of Marangoni spreading, can overshadow the local kinetic roughening of the droplet interface. Marangoni effect ; Physics ; Meteorology ; Convection Pickering emulsions and particle stabilization ; Diffusion and Search Dynamics ; Liquid Crystal Research Advancements