jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: André Luís Fernandes Cauduro | Elizabeth Gager | Keith A. King | Dylan C. McCord | Anthony H. McDaniel | Jonathan R. Scheffe | Juan C. Nino | Farid El Gabaly
Source: Topics in Catalysis (article, 2024-04-09)
Field: Materials Science — Materials Chemistry

Stabilization of Catalytically Active Surface Defects on Ga-doped La–Sr–Mn Perovskites for Improved Solar Thermochemical Generation of Hydrogen X-ray photoelectron spectroscopy ; Water splitting ; Stoichiometry ; Hydroxide ; Hydrogen ; Adsorption ; Oxygen ; Inorganic chemistry ; Materials science ; Vacancy defect ; Catalysis ; Chemistry ; Chemical engineering ; Physical chemistry ; Crystallography Advancements in Solid Oxide Fuel Cells ; Chemical Looping and Thermochemical Processes ; Catalytic Processes in Materials Science
Authors: Yuval Scher | Shlomi Reuveni | Denis S. Grebenkov
Source: The Journal of Chemical Physics (article, 2024-05-08)
Field: Materials Science — Materials Chemistry

Escape from textured adsorbing surfaces The escape dynamics of sticky particles from textured surfaces is poorly understood despite importance to various scientific and technological domains. In this work, we address this challenge by investigating the escape time of adsorbates from prevalent surface topographies, including holes/pits, pillars, and grooves. Analytical expressions for the probability density function and the mean of the escape time are derived. A particularly interesting scenario is that of very deep and narrow confining spaces within the surface. In this case, the joint effect of the entrapment and stickiness prolongs the escape time, resulting in an effective desorption rate that is dramatically lower than that of the untextured surface. This rate is shown to abide a universal scaling law, which couples the equilibrium constants of adsorption with the relevant confining length scales. While our results are analytical and exact, we also present an approximation for deep and narrow cavities based on an effective description of one-dimensional diffusion that is punctuated by motionless adsorption events. This simple and physically motivated approximation provides high-accuracy predictions within its range of validity and works relatively well even for cavities of intermediate depth. All theoretical results are corroborated with extensive Monte Carlo simulations. Scaling ; Diffusion ; Statistical physics ; Surface (topology) ; Monte Carlo method ; Adsorption ; Desorption ; Range (aeronautics) ; Work (physics) ; Surface diffusion ; Physics ; Materials science ; Chemistry ; Geometry ; Mathematics ; Quantum mechanics ; Physical chemistry Pickering emulsions and particle stabilization ; Material Dynamics and Properties ; Theoretical and Computational Physics
Authors: Tingyu Hua | Shanshan Li | Jingli Hu | Wei Yan
Source: Frontiers in Chemistry (article, 2024-08-16)
Field: Chemistry — Organic Chemistry

Effective and selective adsorption of methyl tert-butyl ether on ZSM-5 zeolite: a comparative study The extensive use of methyl <i>tert</i>-butyl ether (MTBE) as a gasoline additive has caused serious environmental problems that need to be addressed urgently. The feasibility of remediation of MTBE-contaminated groundwater by ZSM-5 zeolite with SiO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> ratio of 50/130/360 was explored. The SiO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> ratio had a great influence on the physicochemical properties and structure, as well as the adsorption and mass transfer of MTBE on ZSM-5. The adsorption of MTBE on zeolites with SiO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> ratios of 50 and 130/360 followed the Langmuir and Freundlich models, respectively, and was controlled by different mass transfer processes. The morphology and adsorption capacity of ZSM-5 (50) and ZSM-5 (130) differed significantly, while the differences between ZSM5-(130) and ZSM-5 (360) were less pronounced. ZSM-5 (360) had higher adsorption capacity and adsorption efficiency for MTBE, and the larger BET surface area, pore volume and stronger hydrophobicity were the key factors to promote MTBE adsorption. Compared to activated carbon (AC), ZSM-5 (360) was more effective for MTBE removal at low concentrations (≤200 mg·L<sup>-1</sup>) and had the advantage of selective adsorption of MTBE with the addition of BTEX. In column adsorption, decreasing the concentration had opposite effects on MTBE removal by ZSM-5 and AC. At 5-10 mg·L<sup>-1</sup>, ZSM-5 (360) column reduced effluent concentration and improved bed utilization and removal efficiency. Zeolite ; Adsorption ; ZSM-5 ; Chemistry ; Ether ; Methyl tert-butyl ether ; Organic chemistry ; Catalysis Nanomaterials for catalytic reactions ; Catalysis and Hydrodesulfurization Studies ; Adsorption and biosorption for pollutant removal
Authors: Liliane Oliveira Mota | Yslaine Andrade de Almeida | Diego Fonseca Bispo | Marcos Fabio Farias Souza | Douglas Costa Santos | Raimundo Alves Lima Sobrinho | Iara F. Gimenez
Source: ACS Omega (article, 2024-12-28)
Field: Materials Science — Biomaterials

Preparation of TEMPO-Oxidized Cellulose Hydrogels Modified with β-Cyclodextrin and κ-Carrageenan for Potential Adsorption Applications Cellulose-based materials are promising adsorbents for pollutants and other classes of compounds. Here, we report the preparation of hydrogels via chemical cross-linking of microcrystalline cellulose oxidized by the 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO). The cross-linking process was carried out in the presence of modifiers such as β-cyclodextrin in order to insert hydrophobic cavities or κ-carrageenan due to the presence of negative charges along the molecular chains. Fourier transform infrared spectroscopy (FTIR) characterization evidenced the modification of cellulose chains. Swelling tests showed that all hydrogels reached the swelling equilibrium in the first 10 min of contact, while N<sub>2</sub> adsorption isotherms allowed to evaluate surface areas ranging from 211 to 697 m<sup>2</sup>/g. Adsorption studies using methylene blue showed the key role of negative charges present in polymer chains favoring interactions with this cationic dye, as hydrogels modified with κ-carrageenan were found to have a high adsorption performance. The kinetic analysis of the adsorption process also suggests contributions from chemical interactions, which may involve electron transfer or electron pairing, as the data from all hydrogels showed high-quality fitting with the pseudo-second-order model. Self-healing hydrogels ; Adsorption ; Cellulose ; Cationic polymerization ; Fourier transform infrared spectroscopy ; Microcrystalline cellulose ; Chemistry ; Swelling ; Chemical engineering ; Polymer chemistry ; Polymer ; Methylene blue ; Organic chemistry Advanced Cellulose Research Studies ; Hydrogels: synthesis, properties, applications ; Electrohydrodynamics and Fluid Dynamics
Authors: Tomasz Jóźwiak
Source: Molecules (article, 2024-12-20)
Field: Chemistry — Analytical Chemistry

The Amination of Waste Newsprint Paper with Various Aminating Agents (Ammonia Water, Ethylenediamine, and Diethylenetriamine) to Improve the Sorption Efficiency of Anionic Dyes This study aimed to investigate the effect of aminating waste newsprint paper with different aminating agents (ammonia/ammonia water, ethylenediamine, and diethylenetriamine) for the sorption efficiency of Reactive Black 5 (RB5) and Reactive Yellow 84 (RY84) dyes. To increase the amination efficiency, the paper material was pre-activated with epichlorohydrin. The scope of this study included the characterization of the sorbents tested (FTIR, elemental analysis, BET surface area, porosity, and pH<sub>PZC</sub>), determination of the influence of pH on dye sorption efficiency, sorption kinetics, and the maximum sorption capacity of the dyes. The study results showed that amination with ethylenediamine and diethylenetriamine introduced 87% and 194% more amine groups into the sorbent's structure compared to the treatment with ammonia. The sorption efficiency of RB5 and RY84 on the sorbents tested was the highest in the pH range of 2-3. The sorption equilibrium time ranged from 90 to 150 min and was longer in the case of the unmodified sorbents. The experimental data from the study were best described by the pseudo-second-order model and the Langmuir 1 and 2 models. Amination had a very strong effect on the sorption capacity of newsprint. For example, the sorption capacity of newsprint paper towards RB5 (Q<sub>max</sub> = 7.12 mg/g) increased after amination with ammonia, ethylenediamine, and diethylenetriamine to the value of Q<sub>max</sub> = 182.78 mg/g, Q<sub>max</sub> = 202.7 mg/g, and Q<sub>max</sub> = 231.5 mg/g, respectively. Diethylenetriamine ; Sorption ; Ethylenediamine ; Triethylenetetramine ; Epichlorohydrin ; Amination ; Chemistry ; Nuclear chemistry ; Organic chemistry ; Adsorption ; Catalysis Dye analysis and toxicity ; Adsorption and biosorption for pollutant removal ; Recycling and Waste Management Techniques
Authors: Gerardo León | A.M. Hidalgo | M. Gómez | E. Gómez | Beatriz Miguel
Source: Membranes (article, 2024-01-01)
Field: Chemistry — Organic Chemistry

Efficiency, Kinetics and Mechanism of 4-Nitroaniline Removal from Aqueous Solutions by Emulsion Liquid Membranes Using Type 1 Facilitated Transport 4-Nitroaniline (4NA) is a common organic pollutant that is released into the environment during the manufacture and processing of a wide variety of industrial products. This article describes the use of an emulsion liquid membrane process to remove 4NA from aqueous solutions using a type 1 facilitated transport mechanism. Optimization of the removal process was carried out by analyzing the efficiency of 4NA removal from the feed phase and the initial apparent feed/membrane fluxes and permeabilities under different experimental conditions. The kinetics of the removal process was analyzed using a simplified mass transfer model involving an empirical mass transfer coefficient calculated from experimental data, assuming that the concentrations of 4NA in the external aqueous phase and in the internal <i>w</i>/<i>o</i> emulsion are uniform. The results show that there is a very good fit between the experimental and model data and that the variation in the values of the overall mass transfer coefficients with the experimental conditions coincides with that of the removal efficiency mentioned above. The transport mechanism was studied by identifying the rate-controlling step of the removal process, using models described for adsorption processes, due to the strong parallelism between the transport mechanisms in adsorption and emulsion liquid membrane processes. Emulsion ; Mass transfer ; Aqueous solution ; Membrane ; Aqueous two-phase system ; Adsorption ; Chemistry ; Mass transfer coefficient ; Kinetics ; Chemical engineering ; Phase (matter) ; Chromatography ; Materials science ; Organic chemistry Nanomaterials for catalytic reactions ; Extraction and Separation Processes ; Membrane-based Ion Separation Techniques
Authors: Abha Shukla | Jyoti Shah | Sunidhi Badola | T. K. Mandal | Ved Varun Agrawal | Asit Patra | Lalsiemlien Pulamte | R. K. Kotnala
Source: ACS Omega (article, 2024-02-07)
Field: Chemistry — Organic Chemistry

A Sustainable and Regenerative Process for the Treatment of Textile Effluents Using Nonphotocatalytic Water Splitting by Nanoporous Oxygen-Deficient Ferrite Water is crucial for life. Being the world's third-largest industry, the textile industry pollutes 93 billion cubic meters of water each year. Only 28% of textile wastewater is treated by lower- to middle-income countries due to the costly treatment methods. The present work demonstrates the utilization of surface oxygen defects and nanopores in Mg<sub>0.8</sub>Li<sub>0.2</sub>Fe<sub>2</sub>O<sub>4</sub> (Li-MgF) to treat textile effluents by a highly economical, scalable, and eco-friendly process. Nanoporous, oxygen-deficient Li-MgF splits water by a nonphotocatalytic process at room temperature to produce green electricity as hydroelectric cell. The adsorbent Li-MgF can be easily regenerated by heat treatment. A 70-90% reduction in the UV absorption intensity of adsorbent-treated textile effluents was observed by UV-visible spectroscopy. The oxygen defects on Li-MgF surface and nanopores were confirmed by X-ray photoelectron spectroscopy and Brunauer-Emmett-Teller (BET) measurements, respectively. To analyze the adsorption mechanism, three known organic water-soluble dyes, brilliant green, crystal violet, and congo red, were treated with nanoporous Li-MgF. The dye decolorization efficiency of Li-MgF was recorded to be 99.84, 99.27, and 99.31% at 250 μM concentrations of brilliant green, congo red, and crystal violet, respectively. The results of Fourier transform infrared (FTIR) spectroscopy confirmed the presence of dyes on the material surface attached through hydroxyl groups generated by water splitting on the surface of the material. Total organic carbon analysis confirmed the removal of organic carbon from the dye solutions by 82.8, 77.0, and 46.5% for brilliant green, Congo red, and crystal violet, respectively. Based on the kinetic and isotherm models, the presence of a large number of surface hydroxyl groups on the surface of the material and OH<sup>-</sup> ions in solutions generated by water splitting was found to be responsible for the complete decolorization of all of the dyes. Adsorption of chemically diverse dyes by the nanoporous, eco-friendly, ferromagnetic, economic, and reusable Li-MgF provides a sustainable and easy way to treat textile industry effluents in large amounts. Adsorption ; Crystal violet ; Nanoporous ; Materials science ; Fourier transform infrared spectroscopy ; X-ray photoelectron spectroscopy ; Chemical engineering ; Wastewater ; Oxygen ; Chemistry ; Nuclear chemistry ; Nanotechnology ; Environmental engineering ; Organic chemistry ; Environmental science Nanomaterials for catalytic reactions ; Arsenic contamination and mitigation ; Adsorption and biosorption for pollutant removal
Authors: Cheng Wang | Bingtao Gui | Tianjie Li | Ruiyang Chang | Junxiang Shu | Xiaoqin Deng | Li Chen | Maodan Luo | Bing Jiang | Xu Su | Juan Zhai | Jun Liu | Changsong Zhao
Source: Arabian Journal of Chemistry (article, 2024-10-01)
Field: Chemistry — Inorganic Chemistry

U(Ⅵ) sorption by porous sodium zirconium phosphate pellets from aqueous solution Zirconium phosphate is the first artificially produced layered phosphate that can sorb a variety of nuclides from solutions. Sodium zirconium phosphate (NZP) was a type of α-zirconium phosphate (α-ZrP). The porous sodium zirconium phosphate pellets (p-NZP-P) with a diameter of more than ∼3 mm were prepared and used for uranium sorption. The p-NZP-P could be immersed in solutions for more than 5 days without dissolving and structurally collapsing. The sorption properties of U(Ⅵ) on p-NZP-P in solutions were investigated by both static and dynamic sorption tests. Synthetic p-NZP-P was analyzed in detail using various characterizations to investigate their character and structural changes. In the static sorption experiment, the equilibrium sorption capacity reached the 77.5 ± 1.5 mg·g−1 when the initial concentration of U(Ⅵ) was 100 mg/L, pHinitial = 4.5, T = 25 ℃. Uranium sorption increased by ∼69 % and ∼215 %, respectively, when the initial uranium concentration was increased from 100 to 300 mg·L−1 and the temperature was increased from 15 to 55 °C. Furthermore, uranium sorption increased by ∼541 % when the initial pH increased from 2.5 to 4.5, while it decreased by ∼39 % when the initial pH increased from 4.5 to 7.0. The sorption data corresponded to the pseudo-second-order kinetic model and the Langmuir isotherm model, as well as the theoretically predicted value of sorption capacity (∼199.9 mg·g−1). The results of the dynamic sorption experiment showed that decreasing the quality, increasing the flow rate and the initial U(Ⅵ) concentration would shorten the breakthrough time. The dynamic sorption data agreed well with the Thomas model. The characterization confirmed the porous properties, while the U(Ⅵ) sorption mechanisms relate to –OH coordination and ion exchange. A radioactive rare earth wastewater treatment test suggested that p-NZP-P could be the potential uranium sorbent due to its good stability and efficiency. This paper opened opportunities for the development of practical materials for treating radioactive wastewater in the application of actual scenarios. Chemistry ; Pellets ; Aqueous solution ; Sorption ; Zirconium ; Porosity ; Sodium ; Phosphate ; Inorganic chemistry ; Nuclear chemistry ; Chemical engineering ; Organic chemistry ; Adsorption Radioactive element chemistry and processing ; Chemical Synthesis and Characterization ; Extraction and Separation Processes
Authors: Jaemin Son | Hwon Park | Min-Ju Kim | Jae Hui Park | Ki‐Ho Nam | Jin-Seok Bae
Source: Polymers (article, 2024-06-16)
Field: Materials Science — Polymers and Plastics

Frequency-Dependent Dielectric Permittivity and Water Permeability in Ordered Mesoporous Silica-Grafted Fluorinated Polyimides Polymers with a low dielectric constant (<i>D</i><sub>k</sub>) are promising materials for high-speed communication networks, which demand exceptional thermal stability, ultralow <i>D</i><sub>k</sub> and dissipation factor, and minimum moisture absorption. In this paper, we prepared a series of novel low-<i>D</i><sub>k</sub> polyimide films containing an MCM-41-type amino-functionalized mesoporous silica (AMS) via in situ polymerization and subsequent thermal imidization and investigated their morphologies, thermal properties, frequency-dependent dielectric behaviors, and water permeabilities. Incorporating 6 wt.% AMS reduced the <i>D</i><sub>k</sub> at 1 MHz from 2.91 of the pristine fluorinated polyimide (FPI) to 2.67 of the AMS-grafted FPI (FPI-<i>g</i>-AMS), attributed to the free volume and low polarizability of fluorine moieties in the backbone and the incorporation of air voids within the mesoporous AMS particles. The FPI-<i>g</i>-AMS films presented a stable dissipation factor across a wide frequency range. Introducing a silane coupling agent increased the hydrophobicity of AMS surfaces, which inhibited the approaching of the water molecules, avoiding the hydrolysis of Si-O-Si bonds of the AMS pore walls. The increased tortuosity caused by the AMS particles also reduced water permeability. All the FPI-<i>g</i>-AMS films displayed excellent thermooxidative/thermomechanical stability, including a high 5% weight loss temperature (>531 °C), char residue at 800 °C (>51%), and glass transition temperature (>300 °C). Materials science ; Polyimide ; Thermal stability ; Dielectric ; Glass transition ; Mesoporous silica ; Composite material ; Mesoporous material ; Chemical engineering ; Polymer ; Polymer chemistry ; Dissipation factor ; Permittivity ; Organic chemistry ; Layer (electronics) ; Chemistry Synthesis and properties of polymers ; Silicone and Siloxane Chemistry ; Dielectric materials and actuators
Authors: Jiayu Zhou | Zhaodong Xia | Dongfang Ma | Huanran Wang
Source: Materials (article, 2024-04-10)
Field: Materials Science — Materials Chemistry

Study of Dynamic Failure Behavior of a Type of PC/ABS Composite PC/ABS composites are commonly used in airbag covers. In this paper, uniaxial tensile experiments of a PC/ABS composite at different temperatures and strain rates were conducted. The results showed that the temperature and loading rate affect the mechanical properties of the PC/ABS composite. As the temperature increases, the yield stress decreases and the strain at the moment of fracture increases, but the strain rate at the same temperature has a relatively small effect on the mechanical properties, which are similar to ductile materials. The experimental results were applied to the Abaqus model which considered thermal effects and the exact Johnson-Cook constitutive parameters were calculated by applying the inverse method. Based on the constitutive model and the failure analysis findings acquired by DIC, the uniaxial tensile test at the room temperature and varied strain rates were simulated and compared to the test results, which accurately reproduced the test process. The experiment on target plate intrusion of the PC/ABS composite was designed, and a finite-element model was established to simulate the experimental process. The results were compared with the experiments, which showed that the constitutive and the failure fracture strains were valid. Materials science ; Composite material ; Composite number ; Strain rate ; Ultimate tensile strength ; Constitutive equation ; Fracture (geology) ; Tensile testing ; Finite element method ; Stress (linguistics) ; Structural engineering High-Velocity Impact and Material Behavior ; Mechanical Behavior of Composites ; Structural Response to Dynamic Loads
Authors: Christopher Mbonu | Naresh C. Osti | Di Wu | Pinar Akcora
Source: Journal of Polymer Science (article, 2024-06-15)
Field: Materials Science — Materials Chemistry

Quasi‐elastic neutron scattering study on dynamically asymmetric polymer blends Abstract Compatibility between polymers with different glass transition temperatures controls the thermomechanical properties of blends. This work explores the segmental dynamics of poly(methyl acrylate) (PMA) chains when they are blended with polymers of different rigidities and miscibility. Inspired by the intriguing dynamic asymmetry of chains within the interfacial layer of nanoparticles, this study aims to understand dynamic heterogeneity in dynamically asymmetric blends of PMA/poly(methyl methacrylate) (PMMA), PMA/polystyrene (PS), and PMA/poly(ethylene oxide) (PEO) using the differential scanning calorimetry (DSC) and quasi‐elastic neutron scattering (QENS) measurements below and above the glass transition temperature of PMMA or PS. Results revealed that the segmental jump distance of PMA increased on blending due to volume enhancement. The reduced effective diffusivity of PMA in PMMA is attributed to PMMA's enhanced flexibility (lower characteristic ratio, ) and superior interaction (lower ) when compared with the PS environment. The results demonstrate that the chain rigidity and miscibility affect the free volume, interchain cooperativity, and segmental dynamics in dynamically asymmetric blends. Materials science ; Glass transition ; Miscibility ; Differential scanning calorimetry ; Neutron scattering ; Polymer ; Polystyrene ; Methyl methacrylate ; Polymer chemistry ; Polymer blend ; Dynamic mechanical analysis ; Chemical engineering ; Composite material ; Thermodynamics ; Scattering ; Monomer ; Copolymer Material Dynamics and Properties ; Polymer Nanocomposites and Properties ; Polymer crystallization and properties