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Showing 1 to 20 of 40 for “"Langmuir Isotherm"”.
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Impact of Langmuir isotherm on production behavior of CBM reservoirs
… develop type curves which predict the impact of Langmuir Isotherms on production behavior on a Coalbed Methane reservoir in order to evaluate the economic feasibility and to maximize potential recovery. In order to achieve this objective, the impact of Langmuir isotherm constant on production …
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Investigation of growth kinetics of self-assembling monolayers by means of contact angle, optical ellipsometry, angle-resolved XPS and IR spectroscopy.
… from dilute solutions has been monitored and Langmuir isotherm adsorption curves were fitted to experimental data. A saturated film is formed within approximately 5h after immersion in solutions of concentrations ranging from 0.0005mM to 0.01mM. We found, that the final density of monolayer …
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Insulator-insulator Contact Charging As A Function Of Pressure
… equation is an electrostatic version of the Langmuir isotherm for adsorbed surface particles, which describes well the experimental observations.
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Extraction of Heavy Metals from Aqueous Solutions using Chitosan/Montmorillonite Hybrid Hydrogels
… hybrid hydrogels with high content of chitosan. Langmuir isotherm provides the best fit for Cu(II) adsorption. Finally, the selectivity of CTS/MMT hybrid hydrogels toward various metal ions was determined. The order of selectivity is Cu(II)>Cr(III)˜Co(II)> Ni(II)>Zn(II).
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Noncovalent adsorption of nucleotides in gold nanoparticle DNA conjugates : bioavailability at the bio-nano interface
… adsorption affinities.were studied by Langmuir isotherm analysis. The nanoparticle coverage at saturating concentrations of thiolated DNA varied with oligonucleotide sequence. Saturation coverages correlated well with complement hybridization efficiency. From this we concluded that …
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The purification of industrial wastewater to remove heavy metals and investigation into the use of zeolite as a remediation tool
… iron, zinc, and lead respectively. Both the Langmuir and Freundlich isotherm models were used to characterize the experimental data and to assess the adsorption behaviour of natural zeolite for copper, iron, lead and zinc. The experimental data were slightly better suited to the Langmuir …
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Adsorption and electrostatic potentials at the electrochemical interface
… previously been modeled using extensions of the Langmuir isotherm. At the end of Part I, a simple Monte Carlo model (MC) is applied to a very complex carbon dioxide reduction system to study competitive adsorption. This application of Monte Carlo simulations demonstrates the challenges of …
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Adsorption of Single and Multi-Component Per-and Polyfluoroalkyl Substances (PFAS) at Air-Water Interfaces
… was better predicted by the Freundlich isotherm than the Langmuir isotherm. Varying pore-water velocity revealed that lower velocities increased retardation at lower PFOS concentrations due to the presence of diffusion-limited domains in quasi-saturated conditions. Additionally, PFAS in …
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Development of analytical techniques for detection and remediation of polychlorinated biphenyls in soil and water samples
… for each AC was well described by the Langmuir isotherm modelcorresponding to the presence of a homogeneous surface. Amongst the three ACs, EAChad the highest maximum adsorption capacity (35 mg g-1) compared to PAC(29.4 mg g-1) and GAC (30.4 mg g-1). The adsorption kinetic data obtained …
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A study on stryhcnos potatorum and pisum sativum as natural coagulants for meat food processing wastewater
… was found that the analysis fitted well to the Langmuir isotherm for both natural coagulants. Results show that the percentage of turbidity, TSS, COD, O&G removal by chemical coagulants are quite similar than natural coagulants when lab-scale treatment tank was used to treat the MFPW. This …
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Adsorption of Pollutants on Charcoal Cloth in Simulated Guard Filters
… experimental results could be represented by the Langmuir isotherm for the macropore region of the cloth. The micropore region is highly dependent on the manufacturing process due to variations in the quality of the cloth. This variation obstructs close correlation. The adsorbate-adsorbent mass …
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Plasma-coupled microcombustion
… rates on surfaces are based on the simple Langmuir isotherm for reaction and diffusion on an atomically flat surface. The effects of atomic-scale surface defects can be taken into account with molecular dynamics simulations, but these methods are limited by short accessible time scales. …
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Defluoridation using modified mucilage from indigenous plant material in Vhembe District, Limpopo Province, South Africa
… adsorption capacity when applying both sorbents. Langmuir isotherm best describes the equilibrium sorption based on regression coefficient (R2) ranging from 0.89 to 0.91 (AlDE) and 0.96 to 0.98 (MgDE). A higher fluoride adsorption capacity was recorded at 69.65 mg/g using AlDE and 41.84 mg/g using …
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Investigation of the Colloidal Behaviour of Carbon Black and Perfluorosulfonated Ionomer in Various Solvents
… the primary adsorption was found to follow a Langmuir isotherm with maximum surface coverage around 2.66 x 10-3 g ionomer/m2 Pt/CB. The Pt/CB particle size change due to ionomer adsorption was measured. A maximum size increase around 40nm was found. The size change combined with ionomer …
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Raman and Surface Enhanced Raman Spectroscopy for Forensic Analysis: Case Studies on the Identification of Illicit Substances and Artist Pigments
… associated with each substance were fitted to a Langmuir isotherm calibration model and used for quantitative analysis of fentanyl in heroin mixtures. Linearity was observed at < 6% fentanyl, a significant finding that is consistent with concentrations found in drugs seized during law enforcement …
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Reactions of leuco dyes on acid activated clays
… a beneficial effect on the colour formation. The Langmuir isotherm type plots were used to examine cation adsorption behaviour for 9 types of montmorillonite clays. It was found that cation exchange of clay occurs at at least two different sites; the tetrahedral silica layer sites and the intact …
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Observations and implications of sediment-water interactions in the Niagara impoundment of southwest Virginia
… phosphorus adsorption could be described by the Langmuir Isotherm. The most important nitrogen release mechanism was found to be a cation exchange phenomenon under reducing conditions. Aithough the effective zone of exchange was found to extend only about 2 mm into the sediment surface, the …
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The use of a calibrated three phase (solid-aqueous-gas) plant-wide wastewater treatment model to simulate data on mineral precipitation
… behaviour could be described using the Langmuir and Freundlich isotherm model. Regardless of the adsorbent studied, Langmuir isotherm model fitted well with the adsorption data. The maximum adsorption capacity was found to be 66 mg/g for HC-PS-WAS and 60 mg/g for GAC. The adsorption …
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Untersuchungsergebnisse zur Mobilität und Remobilisierung von Kupfer und Antimon in wasserwirtschaftlich relevanten, porösen Lockergesteinen durch Säulenversuche und mit reaktiver Transportmodellierung
… observed Sb-curves were fitted using two-site Langmuir-isotherm first order kinetics, allowing for quantification of sorption capacities, -affinities and –rates. Applying three-site Langmuir-isotherm first order kinetics also includes precipitation processes. With all models, a satisfying fit …
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Phosphorus adsorption on sandy mine tailings: a comparison of treatments with fertilizers, wood ash, and compost
… to P status. Comparisons were based on standard Langmuir adsorption isotherms, Mehlich III extractable-P, and selected chemical and physical properties including pH, cation exchange capacity, compost rate, and specific surface area. Phosphorus adsorption decreased in the order UT, 1, 3, 6, 8, 9, …
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