jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Delfaa Slman Gassed | Ali Abdulrazzaq Abdulwahid | Ali A. A. Al-Riyahee
Source: Journal of Kufa for Chemical Sciences (article, 2023-08-28)
Field: Chemistry — Analytical Chemistry

Adsorption of Methylene Blue and Safranine Using Activated Carbon of Cinnamon Plant Surface. Cinnamon plant Activated Carbon (C/AC) was prepared by chemical and thermal activation. The adsorption behaviour of (C/AC) in aqueous Methylene blue (MB) and Safranine (S) dyes was investigated and characterized by XRD, TEM and FESEM. The possible mechanism of the adsorption of (MB) and (S) dyes on the (C/AC) surface was studied. The influence of various adsorption control parameters like the initial dye concentration, pH, contact time, and temperature was studied. The data confirmed a high removal of (MB) and (S) at pH=11. The experimental data were fitted to Langmuir and Freundlich isotherms to examine the adsorption mechanism. The adsorption data reveal (MB) with the maximum capacity of (294.11) mg/g and (S) with the capacity of (285.714) mg/g. The kinetic data for different initial dye concentration were computed using pseudo-first order, pseudo-second order, and intraparticle diffusion model. Thermodynamic parameters includes enthalpy (∆H), entropy (∆S), free energy (∆G), and activation energy (Ea) of the adsorption process were calculated and used to interpret the results, and revealed that the adsorption systems were a spontaneous and endothermic process for adsorption of MB and S dyes onto the adsorbent surface. Also, low activation energy values (Ea&lt;40 kJ/mol) were characteristics of the physisorption mechanism and diffusion-controlled process. Physisorption ; Adsorption ; Chemistry ; Freundlich equation ; Endothermic process ; Enthalpy ; Methylene blue ; Activated carbon ; Langmuir ; Chemisorption ; Diffusion ; Aqueous solution ; Activation energy ; Langmuir adsorption model ; Chemical engineering ; Analytical Chemistry (journal) ; Physical chemistry ; Thermodynamics ; Chromatography ; Organic chemistry ; Photocatalysis ; Catalysis Dye analysis and toxicity ; Adsorption and biosorption for pollutant removal
Authors: Florian Pohl | Harald Behrens | Ralf Dohmen
Source: Chemical Geology (article, 2023-12-14)
Field: Materials Science — Ceramics and Composites

Water release from dacitic melts near the glass transition and implications for volcanic eruptions Water content ; Diffusion ; Thermal diffusivity ; Mineralogy ; Analytical Chemistry (journal) ; Glass transition ; Crystallization ; Raman spectroscopy ; Geology ; Chemistry ; Materials science ; Thermodynamics ; Composite material ; Optics ; Environmental chemistry ; Physics Glass properties and applications ; Geological and Geochemical Analysis ; Mineralogy and Gemology Studies
Authors: Matthew Card | Daniel Roxbury
Source: ECS Meeting Abstracts (article, 2023-08-28)
Field: Materials Science — Materials Chemistry

Towards Single-Molecule Analyte Sensing with Single-Walled Carbon Nanotubes Single-walled carbon nanotubes (SWCNTs) have been at the forefront of research for well over a decade due to their unique optical properties. Specifically, the inherent and photostable fluorescence of SWCNTs has been used to create sensitive near-infrared (NIR) sensors for a variety of target analytes, such as dopamine and cholesterol. However, most of the SWCNT sensors are employed in the solution-phase, severely limiting the efficacy due to ensemble measurements which can significantly confound any optical readout. One potential solution involves imaging individual SWCNTs deposited on a surface, unfortunately it is well known that SWCNT florescence is adversely affected by the inherently rough surfaces that are conventionally used for their observation, which emphasizes the need for a novel platform. We therefore devised a spin-coated hydrogel platform that contained SWCNTs in a single focal plane and enabled fluorescent imaging without significantly perturbing their optical properties when compared to the solution-phase. As SWCNT fluorescent microcopy is limited by diffraction, several strategies were employed to improve the sensitivity of analyte detection. When single SWCNTs longer than the diffraction limit were examined, spectral heterogeneity was observed along the length of each SWCNT, suggesting an application in single-molecule analyte detection. A common surfactant sodium deoxycholate (SDC) was investigated as an analyte as it exchanges with DNA oligonucleotides on the surface of DNA-SWCNTs, by which the kinetic response can be used to estimate DNA binding strength. We employed DNA-SWCNTs in the hydrogel platform and observed the kinetic response of individual SWCNTs in response to the addition of SDC. Importantly, the diffusion was intentionally slowed by modifying the top hydrogel layer to examine the kinetic response on a longer time scale, in contrast to the nearly instantaneous response in solution. We observed a decoupling of the spectral properties of each SWCNT, where the fluorescence intensity responded later than the emission wavelength. We then utilized a 1-dimensional diffusion model to estimate the local concentration of each SWCNT. We hypothesize that differences in the SDC functionalization morphology on SWCNTs have a significant impact on this observed effect. Analyte ; Carbon nanotube ; Materials science ; Fluorescence ; Nanotechnology ; Detection limit ; Molecule ; Diffraction ; Oligonucleotide ; DNA ; Chemistry ; Optics ; Chromatography ; Organic chemistry Carbon Nanotubes in Composites ; Advanced biosensing and bioanalysis techniques ; Molecular Junctions and Nanostructures
Authors: Manal M. Khowdiary | Mai Sheta | Nahla A. Taha | Ahmed A. Elhenawy | Basant Eweida
Source: Research Square (preprint, 2023-07-17)
Field: Chemistry — Electrochemistry

Study of Removal conditions optimization for heavy metal from recycled formation water of oil field based on chitosan polymer and its quantum calculation Abstract Specific objective for this study was to stabilize a valid method to remove copper from recycled formation water from oil field. Chitosan used for Cu + 2 adsorption from simulated wastewater. Comparison between commercial (CC) and natural prepared chitosan (NC) from shrimps shell, also CC and NC was grafted for enhancing the efficiency of remove tested metal ions. By studying removal of Cu + 2 across certain parameters as concentration, adsorbent dose, contact time and pH. The results summarized that maximum % removal for all types used was at 20 ppm with value of 94% for CC and NC ,96% for CGC and 98% for NGC after 3hr, 1g and pH = 7. While reaches about 99% removals by increasing adsorbent dose to 4 g for NGC and CGC. Different adsorption isotherms were studied for the remove of Cu + 2 ions. Also the rate of Adsorption for different types of chitosan used was pseudo 1st order, pseudo 2nd order and Elvoich equation. The kinetic data were analyzed by the intra-particle diffusion model and liquid film diffusion model for Cu + 2 adsorption using different types of chitosan to study the mechanism of reaction for each type. Significantly, in order to scale up this effective technique on an industrial scale, response surface methodology (RSM) as a modelling tool Statistical Software for further copper ion removal used. The DFT using B 3 LYP and utilized with 6- 311G* correlation function applied for investigated probs. DFT, and MEPs, also, used to identify the interaction compounds behavior over heavy metal for formation water. Adsorption ; Chitosan ; Copper ; Diffusion ; Response surface methodology ; Metal ions in aqueous solution ; Metal ; Chemistry ; Materials science ; Chemical engineering ; Nuclear chemistry ; Physical chemistry ; Chromatography ; Thermodynamics ; Metallurgy ; Organic chemistry ; Physics Electrochemical Analysis and Applications ; Extraction and Separation Processes ; Analytical chemistry methods development
Authors: Linh Pham Hoai | Nguyễn Quốc Dũng | Khien Nguyen Van
Source: Vietnam Journal of Science and Technology/Science and Technology (article, 2023-02-28)
Field: Materials Science — Materials Chemistry

Adsorption of direct red 79 in wastewater on Fe2Fe1-xMnxO4 (x = 0 - 1) nanoparticles prepared by co-precipitation method Magnetic spinel ferrite nanoparticles Fe2Fe1-xMnxO4 were synthesized by a simple co-precipitation method. The morphology and structures of the synthesized samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM), Raman spectroscopy, and infrared spectroscopy (FTIR). The magnetic properties of the materials were studied using VMS measurement. The results showed that the spinel ferrite nanoparticles formed a single phase of packed face-centered cubic spinel structure. When replacing Mn2+ ions with Fe2+, the crystal structure shifted from the Fe3O4 crystal structure to the MnFe2O4 crystal structure assigned with an increased lattice constant from 6.30 nm to 26.33 nm. Raman and FTIR spectrum analysis showed that when replacing Mn2+ ions with Fe2+, the Mn-O and Fe-O bonds changed significantly. Specifically, the intensity of the Raman spectrum's reflection and the FTIR spectrum's absorption decreased gradually. All the samples exhibited uniform spherical shapes, and particle size varied from 9.8 nm to 30 nm, depending strongly on the substituted concentration. The magnetization curves confirm the soft ferromagnetic behavior with close superparamagnetic properties of Fe2Fe1-xMnxO4 nanoparticles. The material used to study the adsorption of Direct Red 79 (DR79) in water has good adsorption capacity. The adsorption process obeys pseudo-second-order kinetics and also shows compliance with Langmuir, Freundlich and Temkin isotherms. Spinel ; Raman spectroscopy ; Adsorption ; Superparamagnetism ; Materials science ; Analytical Chemistry (journal) ; Fourier transform infrared spectroscopy ; Coprecipitation ; Lattice constant ; Ferrite (magnet) ; Field emission microscopy ; Scanning electron microscope ; Freundlich equation ; Magnetization ; Chemistry ; Chemical engineering ; Diffraction ; Inorganic chemistry ; Physical chemistry ; Magnetic field ; Chromatography ; Optics ; Metallurgy Magnetic Properties and Synthesis of Ferrites ; Iron oxide chemistry and applications ; Nanomaterials for catalytic reactions
Authors: Alexey Zhokh | T. G. Serebrii | P. E. Strizhak
Source: Adsorption Science & Technology (article, 2023-01-01)
Field: Materials Science — Materials Chemistry

Surface Diffusion of C<sub>1</sub>–C<sub>3</sub> Alcohols on Multiwall Carbon Nanotubes The diffusion of methanol, ethanol, and 2-propanol using individual multiwall carbon nanotubes (MWCNT) and MWCNT bundles was investigated for the first time via application of the quartz crystal microbalance. At small times, the release of alcohol obeys the advective mechanism. In contrast, no deviations from Fick’s law were justified at large times. This situation holds for either individual MWCNTs or MWCNT bundles. The utilized MWCNTs are mainly closed from both ends. Therefore, the alcohol release is controlled by surface diffusion. The measured surface diffusivity is in the order of 10 -13 m 2 /s. The obtained diffusivities are in close proximity with the known surface diffusion coefficients on carbon materials. Carbon nanotube ; Chemistry ; Diffusion ; Thermal diffusivity ; Methanol ; Quartz crystal microbalance ; Adsorption ; Surface diffusion ; Alcohol ; Vinyl alcohol ; Crystal (programming language) ; Chemical engineering ; Ethanol ; Nanotechnology ; Physical chemistry ; Thermodynamics ; Organic chemistry ; Materials science ; Polymer Carbon Nanotubes in Composites ; Analytical Chemistry and Chromatography ; Advanced Chemical Sensor Technologies
Authors: Nigel Clarke | Gavin A. Buxton
Source: Soft Matter (article, 2023-12-22)
Field: Materials Science — Polymers and Plastics

Modeling photo-generated charge extraction in bulk heterojunction nanoparticles We present a drift-diffusion model for predicting currents generated through the absorption of solar energy inside bulk heterojunction organic nanoparticles, which are, for example, promising nanomaterials for photo-catalytic water splitting. By coupling a model of the internal microstructure of the nanoparticle with the electronic properties, we show how different characteristics of the microstructure influence the efficiency of the conversion of solar energy into electrical energy. Our model provides a foundation for using computational modeling to optimize the design of photocatalytic nanoparticles. Heterojunction ; Extraction (chemistry) ; Nanoparticle ; Charge (physics) ; Materials science ; Nanotechnology ; Chemical engineering ; Optoelectronics ; Chemistry ; Chromatography ; Physics ; Engineering Transition Metal Oxide Nanomaterials ; Organic Electronics and Photovoltaics ; Photochemistry and Electron Transfer Studies
Authors: Lê Thanh Bắc | Hoai Phuong Nguyen Thi | Duong Duc La | Nguyen Thi Phuong | Tran Thi Cam Le
Source: Vietnam Journal of Catalysis and Adsorption (article, 2023-09-30)
Field: Chemistry — Inorganic Chemistry

Study on Chloroquine phosphate loading capacity of MIL-100(Fe) synthesized by sonochemical method Iron-based metal-organic framework (MIL-100(Fe)) was successfully synthesized by sonochemical method at the frequency of 20.5kHz, power of 1080 W in 10 minutes. Several physical measurements were conducted to characterize the MIL-100(Fe) including XRD, FT-IR, Raman, BET, and SEM methods. The analysis results show that the material has characteristic diffraction peaks at 11o, 19o, 24o, and 28o, the specific surface area of the material reaches 1080 m2/g according to BET, and the particle size from 200-400 nm according to SEM. The chloroquine phosphate loading capacity of MIL-100(Fe) was evaluated according to different adsorption kinetic and isothermal models. The results show that the chloroquine phosphate loading process by material consists of two stages: surface adsorption and intra-particle diffusion. The maximum chloroquine phosphate adsorption capacity of the material reached 236 (mg/g) according to the Langmuir model. Adsorption ; Materials science ; Phosphate ; BET theory ; Specific surface area ; Particle size ; Diffusion ; Particle (ecology) ; Nuclear chemistry ; Raman spectroscopy ; Scanning electron microscope ; Chemical engineering ; Langmuir adsorption model ; Chemistry ; Composite material ; Organic chemistry ; Thermodynamics ; Optics ; Catalysis Metal-Organic Frameworks: Synthesis and Applications ; Advanced Nanomaterials in Catalysis ; Arsenic contamination and mitigation
Authors: Canming Hu | Xupeng Yang | Xiongfei An | Xiaojiao Chen | Chengli Ding
Source: Research Square (preprint, 2023-10-17)
Field: Chemistry — Spectroscopy

Preparation and adsorption properties of cotton linters and coal- gangue-based cellulose/SiO 2 composite aerogels Abstract High-value comprehensive utilization of coal gangue solid waste, reducing synthesis cost and environmental hazards has become an important research direction for green development. In this study, acid-alkali treated coal gangue was used as the silica source, and abundant cotton short staple in Xinjiang was used as the raw material of aerogel. Cellulose/SiO 2 composite aerogels were prepared by sol-gel method using N-N methylenebisacrylamide (MBA) as cross-linking agent and hydrochloric acid (HCl) as catalyst. The samples were characterized and analyzed by XRD, SEM, FT-IR, XPS, EDS, BET, and mechanical property tests. The results show that the composites exhibit low density and high porosity. The density ranges from 0.177–0.371 g/cm − 3 with a high porosity of 88.7%. SEM and BET results showed that the composites showed a three-dimensional mesh structure, and the specific surface area was as high as 325.742 m 2 /g, with a pore size of 21.997nm, which is a mesoporous material. The adsorption performance of the composite aerogel was tested by choosing the dye methylene blue (MB) to simulate wastewater, and the results showed that the adsorption amount of MB was 81.3 mg/g, and the adsorption amount showed a tendency of increasing first and then decreasing with the increase of SiO 2 . It still showed good adsorption after 5 cycles of adsorption experiments. Therefore, the results of this study provide a good application prospect for composite aerogels and a theoretical basis for the development of low-cost novel advanced materials. Adsorption ; Aerogel ; Composite number ; Materials science ; Mesoporous material ; Porosity ; Chemical engineering ; BET theory ; Specific surface area ; Cellulose ; Calcination ; Methylene blue ; Raw material ; Composite material ; Nuclear chemistry ; Catalysis ; Chemistry ; Organic chemistry ; Photocatalysis Aerogels and thermal insulation ; Advanced Cellulose Research Studies ; Supercapacitor Materials and Fabrication
Authors: Baicheng Mei | Tsai-Wei Lin | Grant S. Sheridan | Christopher M. Evans | Charles E. Sing | Kenneth S. Schweizer
Source: arXiv (Cornell University) (preprint, 2023-01-07)
Field: Materials Science — Surfaces, Coatings and Films

How Segmental Dynamics and Mesh Confinement Determine the Selective Diffusivity of Molecules in Crosslinked Dense Polymer Networks The diffusion of molecules (penetrants) of variable size, shape, and chemistry through dense crosslinked polymer networks is a fundamental scientific problem that is broadly relevant in materials, polymer, physical and biological chemistry. Relevant applications include molecular separations in membranes, barrier materials for coatings, drug delivery, and nanofiltration. A major open question is the relationship between molecular transport, thermodynamic state, and chemical structure of the penetrant and polymeric media. Here we address this question by combining experiment, simulation, and theory to unravel the competing effects of penetrant chemistry on its transport in rubbery and supercooled polymer permanent networks over a wide range of crosslink densities, size ratios, and temperatures. The crucial importance of the coupling of local penetrant hopping to the polymer structural relaxation process, and the secondary importance of geometric mesh confinement effects, are established. Network crosslinks induce a large slowing down of nm-scale polymer relaxation which greatly retards the rate of penetrant activated relaxation. The demonstrated good agreement between experiment, simulation, and theory provides strong support for the size ratio variable (effective penetrant diameter to the polymer Kuhn length) as a key variable, and the usefulness of coarse-grained simulation and theoretical models that average over Angstrom scale chemical details. The developed microscopic theory provides a fundamental understanding of the physical processes underlying the behaviors observed in experiment and simulation. Penetrant transport is theoretically predicted to become even more size sensitive in a more deeply supercooled regime not probed in our present experiments or simulations, which suggests new strategies for enhancing selective polymer membrane design. Penetrant (biochemical) ; Polymer ; Chemical physics ; Materials science ; Thermal diffusivity ; Molecular dynamics ; Relaxation (psychology) ; Nanotechnology ; Chemistry ; Thermodynamics ; Computational chemistry ; Physics ; Composite material ; Organic chemistry Polymer Surface Interaction Studies ; Advanced Polymer Synthesis and Characterization ; Polymer crystallization and properties
Authors: Luciana Sampaio Ribeiro | Francisco Javier Ríos | Armindo Santos
Source: Journal of Nanomaterials (article, 2023-04-29)
Field: Materials Science — Materials Chemistry

Porous Stainless Steel Microsphere Synthesis by a Nonconventional Powder Metallurgy Process Useful in the Cermet-Type Advanced Nuclear Fuel Fabrication The fabrication of SS (stainless steel)-UO2 cermet-type advanced nuclear fuel pellets suitable for use in power reactors depends on the development of metallic (SS), ceramic (UO2), and cermet (SS-UO2) microspheres with special characteristics. In this work, a nonconventional powder metallurgy process was developed to produce porous SS microspheres aiming to contribute to solve the bottlenecks found in the SS-UO2 cermet pellet manufacturing. SS, UO2, and SS-UO2 microspheres and SS-UO2 cermet pellets were fabricated and characterized (XRD, EDX, EDS, and SEM). Hard (153 ± 5 µm; 132.2 ± 24.7 MPa; 72% TD) and soft (216 ± 10 µm; 1.3 ± 0.4 MPa; 17% TD) SS, hard (176 ± 6 µm; 147.4 ± 25.0 MPa; 99% TD) UO2, and cermet (SS-UO2) microspheres were obtained. The soft porous SS microspheres did not micronize properly in situ, but their high compressibility favors the compaction of the green SS-UO2 cermet pellet; in this pellet, the UO2 microspheres behaved as rigid inclusions. This favored the obtainment of sintered SS-UO2 cermet pellets with high geometric densities (93% TD), excellent metal–ceramic interaction, and the preservation of the physical integrity of the UO2 microspheres. The usage of high fractions of the SS-UO2 cermet microspheres obtained mixed with low fractions of the said soft porous SS microspheres is already under development. This will enable the fabrication of SS-UO2 cermet pellets with a volume fraction greater than 42 vol% UO2, a homogeneous distribution of UO2 microspheres in the metallic matrix, and null connection between them. The oxide–metal reduction mechanisms were discussed. The applicability of the process is already being explored in the manufacture of porous NdFeB microspheres. Cermet ; Materials science ; Pellets ; Ceramic ; Porosity ; Fabrication ; Powder metallurgy ; Composite material ; Sintering ; Metallurgy ; Pellet Nuclear Materials and Properties ; Radioactive element chemistry and processing ; Nuclear materials and radiation effects