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Littérature scientifique sur le sujet « Desorption kinetic »

Auteur : Grafiati
Publié le 9 mars 2023
Mis à jour le 10 mars 2023

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Articles de revues sur le sujet "Desorption kinetic"

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Li, Zhe, Suwei Xu, Ying Li et Yuji Arai. « Novel Application of Hybrid Anion Exchange Resin for Phosphate Desorption Kinetics in Soils : Minimizing Re-Adsorption of Desorbed Ions ». Soil Systems 4, no 2 (17 juin 2020) : 36. http://dx.doi.org/10.3390/soilsystems4020036.

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The process of phosphate desorption from soils is difficult to measure using stirred batch techniques because of the accumulation of desorbed ions in a bathing solution. To accurately measure the apparent rate coefficient of phosphate desorption from soils, it is necessary to remove the desorbed ions. In this study, a novel hybrid (i.e., iron oxide coated) anion exchange resin was used as a sink to study long-term (seven days) P desorption kinetics in intensively managed agricultural soils in the Midwestern U.S. (total phosphorus (TP): 196–419 mg/kg). The phosphate desorption kinetics in the hybrid anion exchange resin method were compared with those in the other conventional batch desorption method with pure anion exchange resins or without any sink. The extent of P desorption in the hybrid resin methods was >50% of total desorbed phosphate in the other methods. The initial kinetic rate estimated in the pseudo-second-order kinetic model was also highest (3.03–31.35 mg/(g·hr)) in the hybrid resin method when the same soil system was compared. This is because adsorbed P in the hybrid resins was nearly irreversible. The hybrid anion exchange resin might be a new and ideal sink in measuring the P desorption process in soils and sediments.
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Rojas, Raquel, Guillermo Repetto, José Morillo et José Usero. « Sorption/Desorption and Kinetics of Atrazine, Chlorfenvinphos, Endosulfan Sulfate and Trifluralin on Agro-Industrial and Composted Organic Wastes ». Toxics 10, no 2 (14 février 2022) : 85. http://dx.doi.org/10.3390/toxics10020085.

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The use of pesticides presents a risk to terrestrial and aquatic ecosystems. For this reason, the development of strategies to prevent and restore pollution is of the greatest interest, including the adsorption to organic matter. The aim of the present study was to investigate the sorption/desorption and kinetics of atrazine, chlorfenvinphos, endosulfan sulfate, and trifluralin onto several raw organic wastes by batch experiments. Three kinetic models were used to fit the obtained sorption kinetics data and two to fit the obtained adsorption isotherm data; both the Freundlich and pseudo-second-order kinetic models described the sorption isotherms well. The desorption study revealed hysteresis in all cases, showing strong, and not completely reversible, adsorption in most cases, with the exception of atrazine-sawdust and chlorfenvinphos-sawdust and chicken manure combinations, for which responses were weak and irreversible. The best kinetic, adsorption and desorption constants were achieved for the hydrophobic pesticides. With respect to sorption-desorption rates, orujillo was found to be the best adsorbent for atrazine, while composted urban solid waste was more suitable for trifluralin and endosulfan sulfate. Sorption constants and simple correlations indicated that, not only the organic matter content, but also the nature of the organic matter itself, and the pesticide and adsorbent properties, determine pesticide sorption-desorption. The use of wastes as efficient and cheap adsorbents for reducing the risk of pesticide pollution is proposed.
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Bozbag, Selmi Erim, Deniz Şanlı, Barkın Özener, Gökhan Hisar et Can Erkey. « An Aging Model of NH3 Storage Sites for Predicting Kinetics of NH3 Adsorption, Desorption and Oxidation over Hydrothermally Aged Cu-Chabazite ». Catalysts 10, no 4 (8 avril 2020) : 411. http://dx.doi.org/10.3390/catal10040411.

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A unified transient kinetic model which can predict the adsorption, desorption and oxidation kinetics of NH3 over hydrothermally aged Cu-chabazite was developed. The model takes into account the variation of fractional coverages of NH3 storage sites due to hydrothermal aging. In order to determine the fractional coverage of these sites, the catalyst was aged for various times at a certain temperature followed by NH3 adsorption, desorption and temperature-programmed desorption (TPD) experiments. TPD profiles were deconvoluted mainly into three peaks with centres at 317, 456 and 526 °C, respectively. Hydrothermal aging resulted in the progressive increase in the intensity of the peak at 317 °C and decrease in the intensity of the peaks at 456 and 526 °C, along with decreased NH3 oxidation at high temperatures. A model for hydrothermal aging kinetics of the fractional coverage of storage sites was developed using three reactions with appropriate rate expressions with parameters regressed from experimental data. The model was then incorporated into a multi-site kinetic model for the degreened Cu-Chabazite by the addition of aging reactions on each storage site. The effects of both aging time and temperature on the kinetics NH3 adsorption, desorption and oxidation were successfully predicted in the 155-540 °C range. This study is the first step towards the development of a hydrothermal aging-unified kinetic model of NH3-Selective Catalytic Reduction over Cu-chabazite.
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Ugrina, Marin, Nediljka Vukojević Medvidović, Jelena Perić et Marina Trgo. « A study of kinetics and successive sorption/desorption of Zn and Cd uptake onto iron-modified zeolite ». Clay Minerals 50, no 1 (mars 2015) : 117–32. http://dx.doi.org/10.1180/claymin.2015.050.1.11.

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AbstractThe sorption properties of iron-modified zeolite (IMZ) and the kinetics of zinc and cadmium uptake by the IMZ were investigated by the batch method. Two kinetic stages were observed, fast uptake up to 240 min, followed by slow uptake up to equilibrium. Kinetic results were fitted to the reaction and diffusion kinetic models, which indicated that intra-particle diffusion was the rate-limiting step. The Vermeulen’s approximation model was used to predict the quantity of Zn and Cd ions removed per gram of IMZ. The results of the successive sorption and desorption of Zn and Cd ions, with different electrolyte solutions, showed the best desorption efficiency with sodium salt solutions. Four successive repetitions of the sorption/desorption cycles showed a small difference between the amount of sorbed and desorbed Zn and Cd ions from the second to the fourth cycle. This indicates excellent sorption/regeneration properties of the IMZ.
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Nurul Aini, Olyvia Putri Wardhani et Iriany. « DESORPSI β-KAROTEN MINYAK KELAPA SAWIT (CRUDE PALM OIL) DARI KARBON AKTIF MENGGUNAKAN ISOPROPANOL ». Jurnal Teknik Kimia USU 5, no 4 (24 janvier 2017) : 1–7. http://dx.doi.org/10.32734/jtk.v5i4.1547.

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The aim of the research is to study the ability of isopropyl alcohol in the desorption of β-carotene and to obtain kinetic model and desorption isoterm which is suitable in β-carotene desorption. The main material used were isopropyl alcohol and activated carbon containing β-carotene. The variabels used in this research are desorption temperature, activated carbon concentration and parameter observed is concentration of β-carotene in isopropyl alcohol. In the desorption process, activated carbon which adsorp β-carotene was soaked in isopropyl alcohol. To review the desorption kinetics, this research was carried out in various temperature such as 40 oC, 50 oC, and 60 oC. In desorption isoterm process is, various mass of activated carbon was used. Desorption process will be analyzed at spesified time. This research used the first order of desorption kinetics model. The desorption constant rate obtained for 40 oC, 50 oC, and 60 oC are 0,013, 0,014, and 0,036 minute-1 with activation energy is 0,226 kkal/mol. The maximum desorption percentage obtain is 41,94 %. The desorption isoterm model which fit with the β-carotene desorption was Langmuir isoterm model with constanta value 1,2077 L/mg and -0,2218.
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Elbana, Tamer A., et H. Magdi Selim. « Multireaction Modeling of Lead (Pb) and Copper (Cu) Sorption/Desorption Kinetics in Different Soils ». Soil Systems 3, no 2 (31 mai 2019) : 38. http://dx.doi.org/10.3390/soilsystems3020038.

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Batch kinetic experiments were carried out to quantify and describe the sorption/desorption of Cu and Pb in ten soils that exhibited a wide range of properties. Sorption isotherms were quantified using the Langmuir equation, whereas modeling of sorption/desorption kinetics was described using multireaction model (MRM). Results revealed the nonlinear sorption behavior of Cu and Pb in all soils. The ten soils exhibited higher affinity to Pb (6.4 to 36.5 mmol kg−1) in comparison to Cu (3.6 to 22.4 mmol kg−1). Simulation of Cu and Pb kinetic data indicated that the rate of sorption reaction was two orders of magnitude higher than the rate of release. Considering one irreversible site in addition to one-reversible kinetic site improved the estimation of rates of reaction for both Cu and Pb in acidic and alkaline soils. All soils exhibited sorption/desorption hysteresis where Pb-releases ranged between <0.2% and 14.4% of the total sorbed. The respective Cu releases ranged from <0.85% and 23.4%. The multireaction model, which was successful in describing Cu and Pb for all ten soils, provided insight into the processes of sorption/desorption of Cu and Pb in all soils.
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Berez, A., F. Ayari, N. Abidi, G. Schäfer et M. Trabelsi-Ayadi. « Adsorption-desorption processes of azo dye on natural bentonite : batch experiments and modelling ». Clay Minerals 49, no 5 (décembre 2014) : 747–63. http://dx.doi.org/10.1180/claymin.2014.049.5.10.

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AbstractThe purpose of this study was to determine whether a bentonite from the Gafsa deposit (western Tunisia) could be used to remove the Foron Blue 291 (FB) azo dye from wastewater. Batch adsorption and desorption experiments were conducted using untreated and purified bentonite and the influence of contact time, pH, adsorbent mass and temperature of the dye solution on the adsorption of FB was evaluated. Kinetic and isotherm data were fitted using two non-linear kinetic and two non-linear isotherm equations. In addition, the fits were evaluated using the coefficient of determination (R2) and the RMSE. The percentage of dye removal increased with increasing amount of adsorbent until total discolouration was achieved. The adsorption isotherms followed the Langmuir model, with the purified bentonite having a higher adsorption capacity than the raw material due to its higher specific surface area. In addition, the FB molecules were removed from the liquid medium by physical adsorption. Batch desorption experiments were conducted to study the desorption kinetics and the characteristics of the desorption isotherms as well as to quantify the portion of the FB (by mass) that was irreversibly fixed on the solid. Overall, the desorption kinetics were similar to the adsorption kinetics, which indicated that the adsorption-desorption process of azo dye is non-singular; irreversibility occurred that was underlined by an observed thermodynamic index of irreversibility (TII) of 0.69–0.94. The desorption isotherms of the FB depended on the mass of the FB that was initially adsorbed on the bentonite sample, suggesting hysteresis. The amount of irreversibly retained FB was between 46 and 68% of the initial adsorbed mass.
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Korovin, Vadym, Oleksandr Valiaiev, Oleksandr Zontov, Larysa Zontova, Volodymyr Pilchyk et Borys Pysmennyi. « Uranium (VI) sorption from sulphuric solutions by AM-p-2 anionite ». E3S Web of Conferences 109 (2019) : 00039. http://dx.doi.org/10.1051/e3sconf/201910900039.

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Research results were presented for equilibrium and kinetics of uranium sorption by AM-p-2 strong-base anionite from model sulphuric solution. Kinetic experimental data agreed with the pseudo second-order model while equilibrium ones – with the modified Langmuir-Freundlich equation. Testing of the anionite including sorption-desorption process operations used at uranium-mining industrial facilities showed that the resin had high sorption-desorption characteristics.
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Al-Ameri, Baydaa H. A. « Boron Desorption Kinetic in Calcareous Soils ». Journal of Agricultural Science 11, no 5 (15 avril 2019) : 525. http://dx.doi.org/10.5539/jas.v11n5p525.

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Boron release (desorption) is one of the important factors use in estimating fertilizers use efficiency and management of boron in agricultural soils and correlation soil properties with it availability to plant. Chemical kinetics for boron desorption experiment was carried out of boric acid (source for boron fertilizer) under controlled conditions in three calcareous soils (clay, loamy and sandy loam) from central Iraq at three temperatures (278, 298 and 308 Kelvin), by using six mathematical and empirical equations viz. Zero order, First order, Second order, Parabolic diffusion, Power function and Elovich equation were used to study kinetic behavior of boron in calcareous soils. Elovich equation was the best for predication and describing boron released with highest correlation r = 0.942 and t value (9.004), and lowest SE.e (0.530) where boron release rate constant (K) was positively correlated with temperature (r = 0.978). Released rate constant (K) was increased from 0.329 to 0.561 hrs-1 as increasing incubation temperature from 278 to 308 K. Soils texture effect in boron release activation energy (Ea) in three soils under study. The overall average of boron release activation energy of three soils was 15.284 and the highest was 20.923 in clay soil and the lowest amount was 4.596 in sandy loam while loamy soil gave 20.332 KJ mol-1.
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Cruz-Tirado, JP, Arnold Cabanillas, Raúl Siche, J. Espina, Leonardo Díaz-Sánchez et Albert Ibarz. « Bleaching of sugar cane juice using a food-grade adsorber resin and explained by a kinetic model describing the variation in time of the content of adsorbate ». Food Science and Technology International 24, no 3 (14 décembre 2017) : 264–74. http://dx.doi.org/10.1177/1082013217747711.

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This work studies the adsorption of colored compounds in cane juice using a food-grade macroporous adsorber resin without functional groups. The adsorption equilibrium was studied through the adsorption isotherms at 30, 40, and 50 ℃. The absorbance at 420 nm was used to measure the concentration of colored compounds, which enables correlation of the residual concentration with the adsorbed concentration. Furthermore, the efficiency of the adsorption process was studied, from which it was observed that there was an improvement in efficiency with increasing resin content, while the increase in temperature was less important in the process. The kinetic study was performed using the Ibarz model and intraparticle diffusion model, which correctly account for the kinetics of the adsorption process. The adsorption kinetic constant was always greater than the desorption kinetic constant, indicating that the adsorption step predominates over the desorption step.
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Thèses sur le sujet "Desorption kinetic"

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Yüzak, Yaprak. « Adsorption/desorption kinetic studies of vapours on porous carbon materials ». Thesis, University of Newcastle Upon Tyne, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273521.

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Jung, Linda Suna. « Quantitative kinetic analyses of adsorption and desorption processes at the liquid-solid interface with surface plasmon resonance / ». Thesis, Connect to this title online ; UW restricted, 1999. http://hdl.handle.net/1773/11583.

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Araujo, Eloá Moura. « Bioconcentration and desorption kinetic of potentially toxic elements in soils cultivated with horticultural crops in organic and conventional systems ». Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-18052018-114411/.

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Potentially toxic elements (PTEs) can be absorbed and accumulated in vegetables organ and tissues, and this is an important channel through which PTEs can enter into the food chain. Soil management may interfere in the behavior of PTEs in the system. So, the study of the dynamics of elements in the soil is fundamental to a better understanding of factors that influence soil-plant transfer. In the state of Pernambuco, Brazil, the production of vegetables is mainly concentrated in small or medium organic and conventional farms located in the Agreste and Sao Francisco regions. Our aims in this research were: i) to determine the contents of PTEs in soil and in vegetables produced under conventional and organic systems in garden soils of Pernambuco; ii) to investigate the forms of the PTEs and their uptake by the vegetables based on different soil-plant transfer factors; iii) to use the calculated transfer factors to assess the human risk exposure; iv) to assess the effect of aging and organic matter (OM) on copper (Cu) desorption in garden soils; v) to determine if manure application to soils increases water soluble Cu concentrations; and vi) to verify the efficiency of machine learning techniques in the classification of vegetables produced under organic and conventional systems. Acid and complexing solutions were employed to extract total contents of PTEs in plants and to extract pseudototal, reactive and bioavailable fractions of the PTEs in soils. Soil-plant transfer factors and human risk assessment were calculated based on the determined levels of PTEs. Kinetic assays were developed using rates of organic composts added to Cu-spiked soils to model the Cu desorption. Water extractable Cu and dissolved organic carbon (DOC) were extracted from soils amended with dairy manure, and the Cu-DOC interactions were studied using spectroscopic techniques. Lettuce (Lactuca sativa) leaves had the highest capacity to accumulate PTEs; conventional system promoted higher PTEs values in soils and plants than the organic production; regardless of the scenario, children and adults in contact to vegetables cropped in organic system have a lower health risk than individuals exposed to lettuce leaves conventionally produced. The addition of OM promoted greater Cu desorption, while aging lead to a reduction in the Cu release. The Fouriertransform infrared spectroscopy spectra showed increase in the presence of aliphatic and carboxylic groups in the extracts from the manure-amended soils. Carboxylic acid functional groups on the DOC formed strong bonds with Cu, which can promote Cu transport as dissolved Cu-organic complexes in the soil profile. The Support Vector Machine had an accuracy over 90% to classify the vegetables in the two groups (organic and conventional); and this high assertiveness rate highlights the potential of using elemental quantification and algorithms as support techniques in the process of authenticity and inspection of organic products.
Elementos potencialmente toxicos (EPTs) podem estar biodisponiveis para serem absorvidos e acumulados nos tecidos e orgaos vegetais, sendo esta uma importante rota de entrada de EPTs na cadeia alimentar. O manejo do solo pode interferir no comportamento dos EPTs no sistema. Desta forma, o estudo da dinamica desses elementos no solo e fundamental para melhor entendimento dos fatores que influenciam a transferencia solo-planta. No estado de Pernambuco, a producao de hortalicas se concentra em intensos cultivos organicos e convencionais localizados em pequenas ou medias propriedades, principalmente na regiao Agreste e Sao Francisco. Nossos objetivos neste trabalho foram: i) determinar os teores de EPTs no solo e nas hortalicas produzidas em sistemas convencionais e organicos em hortas de Pernambuco; ii) investigar as formas de EPTs e sua absorcao pelas hortalicas com base em diferentes fatores de transferencia solo-planta; iii) usar os fatores de transferencia calculados para investigar o risco de exposicao aos humanos; iv) estudar o efeito do tempo e da materia organica (MO) na dessorcao de cobre (Cu) em solos de horta; v) determinar se a aplicacao de esterco aumenta a concentracao de Cu soluvel em agua; e vi) verificar a eficiencia de tecnicas machine learning na classificacao de hortalicas produzidas em sistemas organicos e convencionais. Solucoes acidas e complexantes foram utilizadas para extrair os teores totais de EPTs nas plantas e os teores pseudototal, reativo e biodisponivel dos EPTs no solo. Fatores de transferencia solo-planta e avaliacao de risco humano foram calculados com base nos teores de EPTs. Estudos de cinetica foram desenvolvidos apos adicao de composto organico em solos contaminados com Cu para modelar a dessorcao de Cu. Cu soluvel em agua e carbono organico dissolvido (COD) foram extraidos de solos adubados com esterco, a interacao Cu-COD foi estudada usando tecnicas espectroscopicas. Folhas de alface (Lactuca sativa) apresentaram a maior capacidade de acumular EPTS; o sistema convencional promoveu maiores tores de EPTs nos solos e plantas do que o sistema organico; independentemente do cenario, criancas e adultos em contato com vegetais produzidos em sistema organico tem um menor risco do que os individuos que consomem folhas de alface convencionalmente produzidas. A adicao de MO promoveu maior dessorcao de Cu, enquanto o aumento no tempo de contato reduziu a liberacao de Cu. Os graficos da espectroscopia de infravermelho com transformada de Fourier mostraram um aumento na presenca de grupos funcionais alifaticos e carboxilicos nos extratos de solos adubados com esterco. Esses grupos funcionais no COD formam ligacoes fortes com Cu, o que promove o transporte do elemento na forma de complexos organicos dissolvidos no perfil do solo. O modelo Support Vector Machine apresentou acuracia superior a 90% na classificacao das hortalicas em dois grupos (organicas e convencionais); e a alta taxa de assertividade mostra o potencial do uso de quantificacao elementar e algoritmos como tecnicas auxiliares no processo de autenticidade de inspecao de produtos organicos.
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Lalley, Jacob. « Phosphate Remediation and Recovery from Lake Water using Modified Iron Oxide-based Adsorbents ». University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1427812939.

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Dittler, Roy Frank. « Reducing Ultra-High-Purity (UHP) Gas Consumption by Characterization of Trace Contaminant Kinetic and Transport Behavior in UHP Fabrication Environments ». Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/321322.

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Trends show that the fraction of the world's population with electronic devices using modern integrated circuits is increasing at a rapid rate. To meet consumer demands: less expensive, faster, and smaller electronics; while still making a profit, manufacturers must shrink transistor dimensions while increasing the number of transistors per integrated circuit; a trend predicted by Gorden E. Moore more than 44 years prior. As CMOS transistors scale down in size, new techniques such as atomic-layer deposition (ALD) are used to grow features one atomic layer at a time. ALD and other manufacturing processes are requiring increasingly stringent purities of process gases and liquids in order to minimize circuit killing defects which reduces yield and drives up manufacturing cost. Circuit killing defects caused by impurity incursions into UHP gas distribution system can come from a variety of sources and one of the impurity transport mechanisms investigated was back diffusion; the transport of impurities against convective flow. Once impurity incursions transpire, entire production lines are shut down and purging with UHP gas is initiated; a process that can take months thus resulting in tens of millions of dollars in lost revenue and substantial environment, safety, and health (ESH) impacts associated with high purge gas consumption. A combination of experimental investigation and process simulation was used to analyze the effect of various operational parameters on impurity back diffusion into UHP gas distribution systems. Advanced and highly sensitive analytical equipment, such as the Tiger Optics MTO 1000 H2O cavity ring-down spectrometer (CRDS), was used in experiments to measure real time back diffusing moisture concentrations exiting an electro-polished stainless-steel (EPSS) UHP distribution pipe. Design and operating parameters; main and lateral flow rates, system pressure, restrictive flow orifice (RFO) aperture size, and lateral length were changed to impact the extent of back diffusing impurities from a venting lateral. The process model developed in this work was validated by comparing its predictions with data from the experiment test bed. The process model includes convection, molecular diffusion in the bulk, surface diffusion, boundary layer transport, and all modes of dispersion; applicable in both laminar and turbulent flow regimes. Fluid dynamic properties were directly measured or were obtained by solving Navier-Stokes and continuity equations. Surface diffusion as well as convection and dispersion in the bulk fluid played a strong role in the transport of moisture from vents and lateral branches into the main line. In this analysis, a dimensionless number (Peclet Number) was derived and applied as the key indicator of the relative significance of various transport mechanisms in moisture back-diffusion. Guidelines and critical values of Peclet number were identified for assuring the operating conditions meet the purity requirements at the point of use while minimizing UHP gas usage. These guidelines allowed the determination of lateral lengths, lateral diameters, flow rates, and restrictive flow device configurations to minimize contamination and UHP gas consumption. Once a distribution system is contaminated, a significant amount of purge time is required to recover the system background due to the strong interactions between moisture molecules and the inner surfaces of the components in a gas distribution system. Because of the very high cost of UHP gases and factory downtime, it is critical for high-volume semiconductor manufacturers to reduce purge gas usage as well as purge time during the dry-down process. The removal of moisture contamination in UHP gas distribution systems was approached by using a novel technique dubbed pressure cyclic purge (PCP). EPSS piping was contaminated with moisture, from a controlled source, and then purged using a conventional purge technique or a PCP technique. Moisture removal rates and overall moisture removal was determined by measuring gas phase moisture concentration in real time via a CRDS moisture analyzer. When compared to conventional purge, PCP reduced the time required and purge gas needed to clean the UHP gas distribution systems. However, results indicate that indiscriminately initiating PCP can have less than ideal or even detrimental results. An investigation of purge techniques on the removal of gas phase, chemisorbed, and physisorbed moisture, coupled with the model predictions, led to the testing of hybrid PCP. The hybrid PCP approach proved to be the most adaptable purge technique and was used in next phase of testing and modeling. Experiments and modeling progressed to include testing the effectiveness of hybrid PCP in systems with laterals; more specifically, laterals that are "dead volumes" and results show that hybrid PCP becomes more purge time and purge gas efficient in systems with increasing number and size of dead volumes. The process model was used as a dry-down optimization tool requiring inputs of; geometry and size, temperature, starting contamination level, pressure swing limits of inline equipment, target cleanliness, and optimization goals; such as, minimizing pure time, minimizing purge gas usage, or minimizing total dry-down cost.
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GHAANI, MOHAMMAD REZA. « Study of new materials and their functionality for hydrogen storage and other energy applications ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2014. http://hdl.handle.net/10281/49808.

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The first part of this thesis deals with hydrogen storage materials, in view of their applications as promising energy carriers. One of the main open problems with these materials is: how can their decomposition temperature be lowered, when hydrogen is wanted to be released, so as to improve the energy efficiency of the process. A possible answer is given by joint decomposition of two or more hydrides, if very stable mixed compounds are formed (‘hydride destabilization’). Aiming at this result, the new hydride composite 2LiBH4-Mg2FeH6 was considered, it was synthesized, and its thermodynamic and kinetic properties were investigated. In the second part of this thesis work lithium oxide materials, of relevant interest for applications to batteries, were investigated. The chemical lithiation reaction of niobium oxide was considered, as equivalent to the electrochemical process of lithium insertion on discharging a Nb2O5 cathode vs. a metal Li anode. Thus, the Li2Nb2O5 compound was synthesized by reaction of monoclinic a-Nb2O5 with n-butyllithium.This material was investigated by neutron powder diffraction (D2B equipment at ILL, France) and its structure was Rietveld refined in space group P2 to wRp=0.045, locating the Li atoms inserted in the a-Nb2O5 framework.
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Szost, Blanka Angelika. « Hydrogen trapping in bearing steels : mechanisms and alloy design ». Thesis, University of Cambridge, 2013. https://www.repository.cam.ac.uk/handle/1810/244934.

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Hydrogen embrittlement is a problem that offers challenges both to technology and to the theory of metallurgy. In the presence of a hydrogen rich environment, applications such as rolling bearings display a significant decrease in alloy strength and accelerated failure due to rolling contact fatigue. In spite of these problems being well recognised, there is little understanding as to which mechanisms are present in hydrogen induced bearing failure. The objective of this thesis are twofold. First, a novel alloy combining the excellent hardness of bearing steels, and resistance to hydrogen embrittlement, is proposed. Second, a new technique to identify the nature of hydrogen embrittlement in bearing steels is suggested. The new alloy was a successful result of computer aided alloy design; thermodynamic and kinetic modelling were employed to design a composition and heat treatment combining (1) fine cementite providing a strong and ductile microstructure, and (2) nano-sized vanadium carbide precipitates acting as hydrogen traps. A novel technique is proposed to visualise the migration of hydrogen to indentation-induced cracks. The observations employing this technique strongly suggest that hydrogen enhanced localised plasticity prevails in bearing steels. While proposing a hydrogen tolerant bearing steel grade, and a new technique to visualize hydrogen damage, this thesis is expected to aid in increasing the reliability of bearings operating in hydrogen rich environments.
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Berhane, Tedros Mesfin. « KINETIC AND EQUILIBRIUM SORPTION EXPERIMENTS INVESTIGATING PALYGORSKITE-MONTMORILLONITE AS A POTENTIAL FILTER MEDIUM FOR REMOVAL OF PHARMACEUTICALS AND ENDOCRINE-DISRUPTING COMPOUNDS ». Miami University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=miami1429882830.

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Hurley, Caitlin Mae. « Kinetic study of hydrogen-material interactions in nickel base alloy 600 and stainless steel 316L through coupled experimental and numerical analysis ». Phd thesis, Toulouse, INPT, 2015. http://oatao.univ-toulouse.fr/14454/1/hurley.pdf.

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In France all of the nuclear power plant facilities in service today are pressurized water reactors (PWR). Some parts of the PWR in contact with the primary circuit medium, such as the steam generator tubes (fabricated in nickel base alloy A600) and some reactor core internal components (fabricated in stainless steel 316L), can fall victim to environmental degradation phenomena such as stress corrosion cracking (SCC). In the late 1950's, H. Coriou observed experimentally and predicted this type of cracking in alloys traditionally renowned for their SCC resistance (A600). Just some 20 to 30 years later his predictions became a reality. Since then, numerous studies have focused on the description and comprehension of the SCC phenomenon in primary water under reactor operating conditions. In view of reactor lifetime extension, it has become both critical and strategic to be capable of simulating SCC phenomenon in order to optimize construction materials, operating conditions, etc. and to understand the critical parameters in order to limit the damage done by SCC. This study focuses on the role hydrogen plays in SCC phenomenon and in particular H-material interactions. Hydrogen, from primary medium in the form of dissolved H gas or H from the water, can be absorbed by the alloy during the oxidation process taking place under reactor operating conditions. Once absorbed, hydrogen may be transported across the material, diffusing in the interstitial sites of the crystallographic structure and interacting with local defects, such as dislocations, precipitates, vacancies, etc. The presence of these [local defect] sites can slow the hydrogen transport and may provoke local H accumulation in the alloy. This accumulation could modify the local mechanical properties of the material and favor premature rupture. It is therefore essential to identify the nature of these H-material interactions, specifically the rate of H diffusion and hydrogen trapping kinetics at these defects. Concerning these H-trap site interactions, literature presents very few complete sets of kinetic data; it is therefore necessary to study and characterize these interactions in-depth. This work is composed of two interdependent parts: (i) the development of a calculation code capable to manage these H-material interactions and (ii) to extract the kinetic constants for trapping and detrapping from experimental results in order to fuel the simulation code and create a solid database. Due to the complexity of industrial materials (A600 and SS316L), \enquote{model materials} were elaborated using a series of thermomechanical treatments allowing for the study of simplified systems and the deconvolution of the different possible trapped and interstitial hydrogen contributions. These \enquote{model} specimens were charged with deuterium (an isotopic hydrogen tracer) by cathodic polarization. After charging, specimens were subjected to thermal desorption mass spectroscopy (TDS) analysis where the deuterium desorption flux is monitored during a temperature ramp or at an isotherm. Interstitial diffusion and kinetic trapping and detrapping constants were extracted from experimental TDS spectra using a numerical fitting routine based upon the numerical resolution of the McNabb and Foster equations. This study allowed for the determination of the hydrogen diffusion coefficient in two alloys, Ni base alloy 600 and stainless steel 316L, and the kinetic trapping and detrapping constants at two trap site types, chromium carbides and dislocations. These constants will be used to construct a kinetic database which will serve as input parameters for a numerical model for the prediction and simulation of SCC in PWRs
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Thinon, Olivier. « CO conversion over dual-site catalysts by the Water-Gas Shift Reaction for fuel cell applications : comparative mechanistic and kinetic study of gold and platinum supported catalysts ». Thesis, Lyon 1, 2009. http://www.theses.fr/2009LYO10187.

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Les piles à combustible, alimentée par de l’hydrogène, représentent une solution prometteuse pour limiter la pollution. L’une des alternatives économiques envisagées à court et moyen terme est de produire l’hydrogène à partir d’un carburant tel que le méthane ou le bio-éthanol. Cette transformation a pour objectif d’obtenir un mélange de gaz riche en hydrogène avec une très faible teneur en CO, ce dernier étant un poison pour les piles de type PEM. La réaction de Water-Gas Shift (WGS) est une étape clé du procédé ; elle convertit CO en CO2 par réaction avec l’eau et fournit une quantité d’hydrogène supplémentaire. Des catalyseurs métalliques (Pt, Pd, Ru, Rh, Au, Cu) supportés sur des oxydes (CeO2, TiO2, ZrO2, Fe2O3, CeO2/Al2O3) ont été comparés dans des conditions de WGS identiques en présence de CO2 et H2. Une étude cinétique a été réalisée sur les catalyseurs Pt/CeO2, Au/CeO2, Pt/TiO2 et Au/TiO2. Les énergies d’activation apparentes et les ordres de réaction ont été déterminés à partir d’un modèle de type loi de puissance. Un mécanisme réactionnel avec deux sites a été proposé pour décrire les différentes activités des 4 catalyseurs. Des expériences de désorption programmée en température ont été réalisées pour déterminer les paramètres cinétiques sur le support
The Fuel Cells are promising solution to reduce the air pollution. One of the cost-efficient alternatives is to produce hydrogen from another fuel such as methane or bio-ethanol. A hydrogen fuel processor consists in generating a hydrogen-rich mixture and reducing the carbon monoxide content, as PEM fuel cells are very low CO tolerance. One of these units is the water-gas shift reactor, which converts CO into CO2 by the reaction with water and provides additional hydrogen. Catalysts based on a metal (Pt, Pd, Ru, Rh, Au, Cu) supported on an oxide (CeO2, TiO2, ZrO2, Fe2O3, CeO2/Al2O3) were compared for the WGS reaction in the same conditions and in the presence of CO2 and H2. A kinetic study was conducted on catalysts Pt/CeO2, Au/CeO2, Pt/TiO2 and Au/TiO2. A power law rate model was used to determine apparent activation energies and reaction orders. A dual-site reaction mechanism was proposed to explain the different activities between the four catalysts. The sorption parameters of H2O and CO2 on the supports was quantitatively determined from temperature-programmed desorption experiments
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Livres sur le sujet "Desorption kinetic"

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Braithwaite, Annamarie. The kinetics of uranium desorption from enriched soils. Manchester : Universityof Manchester, 1994.

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Diffusion in natural porous media : Contaminant transport, sorption/desorption and dissolution kinetics. Boston : Kluwer Academic Publishers, 1998.

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Grathwohl, Peter. Diffusion in Natural Porous Media : Contaminant Transport, Sorption/Desorption and Dissolution Kinetics. Boston, MA : Springer US, 1998. http://dx.doi.org/10.1007/978-1-4615-5683-1.

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Workshop on Interface Phenomena (1986 New Brunswick). Kinetics of interface reactions : Proceedings of a Workshop on Interface Phenomena, Campobello Island, Canada, September 24-27, 1986. Sous la direction de Grunze M. 1947- et Kreuzer H. J. Berlin : Springer-Verlag, 1987.

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Winkler, Adolf. Reaction studies on nanostructured surfaces. Sous la direction de A. V. Narlikar et Y. Y. Fu. Oxford University Press, 2017. http://dx.doi.org/10.1093/oxfordhb/9780199533046.013.12.

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This article examines the properties of some self-organized nanostructured surfaces with respect to specific model reactions, from a surface-science point of view. It begins with an overview of the most important types of nanostructured surfaces, their preparation and characterization. It then considers the fundamentals of reaction processes, focusing on the kinetics and dynamics of adsorption and desorption. It also describes the experimental techniques used in the context of reaction studies under ultrahigh-vacuum conditions. Finally, it presents some experimental results of model reactions, including hydrogen adsorption and desorption on stepped nickel surfaces, methanol adsorption on self-assembled copper-copper oxide surfaces, and hydrogen desorption and water formation on vanadium-oxide nanostructures on palladium surfaces.
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Grathwohl, Peter. Diffusion in Natural Porous Media : Contaminant Transport, Sorption/Desorption and Dissolution Kinetics. Springer, 2012.

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Grathwohl, Peter. Diffusion in Natural Porous Media : Contaminant Transport, Sorption/Desorption and Dissolution Kinetics. Springer London, Limited, 2012.

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Peterlinz, Kevin Andrew. Kinetics and dynamics of CO desorption, CO oxidation, and O absorption on Rh(111) using time resolved specular helium scattering. 1993.

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Chapitres de livres sur le sujet "Desorption kinetic"

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Wang, Sheng-Kai. « Desorption Kinetics of GeO from GeO2/Ge ». Dans Kinetic Studies in GeO2/Ge System, 47–99. Boca Raton : CRC Press, 2022. http://dx.doi.org/10.1201/9781003284802-3.

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Selim, H. M., et Liwang Ma. « Modeling Nonlinear Kinetic Behavior of Copper Adsorption-Desorption in Soil ». Dans SSSA Special Publications, 189–212. Madison, WI, USA : Soil Science Society of America, 2015. http://dx.doi.org/10.2136/sssaspecpub56.c6.

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Baleanu, Dumitru, Yeliz Yolcu Okur, Salih Okur et Kasim Ocakoglu. « Parameter Identification of the Langmuir Model for Adsorption and Desorption Kinetic Data ». Dans Nonlinear and Complex Dynamics, 97–106. New York, NY : Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4614-0231-2_7.

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Kreuzer, Hans Jürgen, et Zbigniew Wojciech Gortel. « Desorption Times ». Dans Physisorption Kinetics, 142–97. Berlin, Heidelberg : Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-82695-5_5.

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Feldmann, D., J. Kutzner et K. H. Welge. « Dissociative Desorption of CH3I by UV-Laser Radiation : Kinetic and Internal Energy of the Neutral Fragments ». Dans Springer Series in Surface Sciences, 93–96. Berlin, Heidelberg : Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/978-3-642-84145-3_11.

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Aptel, J. D., A. Carroy, P. Dejardin, E. Pefferkorn, P. Schaaf, A. Schmitt, R. Varoqui et J. C. Voegel. « Adsorption and Desorption of Synthetic and Biological Macromolecules at Solid-Liquid Interfaces : Equilibrium and Kinetic Properties ». Dans ACS Symposium Series, 222–38. Washington, DC : American Chemical Society, 1987. http://dx.doi.org/10.1021/bk-1987-0343.ch015.

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Vannice, M. Albert. « Adsorption and Desorption Processes ». Dans Kinetics of Catalytic Reactions, 87–105. Boston, MA : Springer US, 2005. http://dx.doi.org/10.1007/978-0-387-25972-7_5.

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Chorover, Jon, et Mark L. Brusseau. « Kinetics of Sorption—Desorption ». Dans Kinetics of Water-Rock Interaction, 109–49. New York, NY : Springer New York, 2008. http://dx.doi.org/10.1007/978-0-387-73563-4_4.

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Kreuzer, H. J. « Theory of Desorption Kinetics ». Dans Chemistry and Physics of Solid Surfaces VII, 259–81. Berlin, Heidelberg : Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-73902-6_9.

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Gupta, Raj K., I. P. Abrol, Charles W. Finkl, M. B. Kirkham, Marta Camps Arbestain, Felipe Macías, Ward Chesworth et al. « Solute Sorption‐Desorption Kinetics ». Dans Encyclopedia of Soil Science, 739–44. Dordrecht : Springer Netherlands, 2008. http://dx.doi.org/10.1007/978-1-4020-3995-9_569.

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Actes de conférences sur le sujet "Desorption kinetic"

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Ma, Mingwang, Ruiyun Wan, Yuan Wang, Yanlin Cheng, Li Liang, Xiaohua Tan et Wei Xiang. « The Kinetics of Hydrogen Desorption From Zirconium Hydride ». Dans 2013 21st International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/icone21-15869.

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Thermal desorption spectroscopy (TDS) was used to study the thermal desorption kinetics of zirconium hydride films, which were deposited on molybdenum substrates and thermally charged with gas phase hydrogen. The observed desorption peaks were attributed to phase transforming steps. The activation energy and pre-exponential factor for desorption kinetics was estimated as 116 kJ/mol and 8762 s−1 according to Kissinger relation, respectively. A simulation of TDS spectra was made, which showed that the desorption process followed a first order kinetics. The kinetic parameters were then utilized to predict weight loss behavior at a temperature profile. Pressure effects that can potentially reduce the desorption rate were discussed.
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Brancher, Ricardo D., Stefan Stefanov, Irina Graur et Aldo Frezzotti. « Kinetic theory description of gas adsorption-desorption on a solid surface ». Dans 31ST INTERNATIONAL SYMPOSIUM ON RAREFIED GAS DYNAMICS : RGD31. AIP Publishing, 2019. http://dx.doi.org/10.1063/1.5119656.

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Xiong, Fengyang, Zhenxue Jiang, Hailong Lu, Joachim Moortgat et Mileva Radonjic. « OBSERVATION AND MODELING OF KINETIC EMISSION OF SHALE GAS USING CANISTER DESORPTION TESTING ». Dans GSA Connects 2021 in Portland, Oregon. Geological Society of America, 2021. http://dx.doi.org/10.1130/abs/2021am-368878.

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Bares, S. J., et R. B. Hall. « Time Resolved Kinetic Studies of Molecular Decomposition on Ni(100) using Laser Induced Desorption ». Dans Microphysics of Surfaces, Beams, and Adsorbates. Washington, D.C. : Optica Publishing Group, 1985. http://dx.doi.org/10.1364/msba.1985.tub2.

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Laser induced desorption (LID) of surface bound species is rapidly developing into an important technique for studying the dynamics of the adsorbate-substrate bond. We report here the first application of this new technique to time resolved studies of reaction kinetics on a clean metal surface. In particular, measurements of decomposition rates of methanol to form the methoxy intermediate and hydrogen are described. Surprisingly, the decomposition curves cannot be interpreted assuming a simple first order rate expression; rather, a pseudo-second order rate law is invoked to explain the data. Additional insight into the methanol decomposition reaction is obtained from studies of the reaction rate dependence on the initial concentration of methanol. Preliminary results using this technique to study the decomposition of ethylene on Ni(100) will also be discussed and compared to the methanol results.
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Kelly, Roger, et R. W. Dreyfus. « Effect of near-surface gas-phase collisions on desorption measurements ». Dans OSA Annual Meeting. Washington, D.C. : Optica Publishing Group, 1987. http://dx.doi.org/10.1364/oam.1987.thj2.

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If desorbed particles have a sufficiently low number density they disperse collisionlessly. This means that if, for example, the mechanism is thermally activated, a time-of-flight spectrum yields the surface temperature through the relation kT = Ê/2, Ê being the most probable kinetic energy, and the signal is proportional to cosθ. If, on the other hand, the number density is high enough for a few (estimates range from 3 to 20) collisions to occur, a so-called Knudsen layer is formed. We first show how this problem can be solved analytically and then explore its consequences to thermally activated desorption. In particular, when there is a Knudsen layer, (1) 18-24% of the desorbed particles are found to recondense, (2) the temperature falls to 70-90% of the value at the surface, but this is more than compensated by a center-of-mass velocity, (3) the relation between kT and Ê changes significantly, and (4) the angular distribution becomes strongly forward peaked (~cos3θ). We finally consider the effect of a Knudsen layer on an electronic desorption process, especially on the energy spectrum and on the angular distribution.
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Nwaka, Nnamdi, et Yuanhang Chen. « Numerical Simulations of Riser Gas Behavior in Non-Aqueous Muds Using a Modified Drift Flux Model ». Dans ASME 2019 38th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/omae2019-96672.

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Abstract Real-time prediction of riser gas behavior is of great importance in well control. Single bubble models have, thus far, been used to describe gas-in-riser events and define riser equilibrium. These models have however not considered the transient nature of desorption of gas influx from non-aqueous fluids (NAFs) during migration or circulation in a riser. This paper uses a modified drift-flux model (DFM) to more properly describe gas-in-riser events by incorporating time-dependent mass transfer processes in NAFs. In this paper, we modified the DFM to account for the gas-liquid mass transfer due to the time dependent desorption of the gas phase. The advection upstream splitting model (AUSMV) hybrid scheme was used to solve the model. The time dependent mass transfer is calculated using a kinetic model developed based on recent experimental data. The capability of this model to improve riser gas management is demonstrated using a case study and the simulations are compared to when mass transfer between gas influx and NAF is not considered. Results also show that the severity of unloading and depth of the riser equilibrium can be underestimated if a time dependent desorption is not considered. The concept of riser equilibrium has been, thus far, developed without due consideration of mass transport of gas phase in the mud. This paper factors in the time-dependent desorption of the gas phase in the mud for a more realistic prediction of riser gas unloading events.
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Tran Thuy, Tuyet Mai, et Dung Van Nguyen. « Octahedral Molecular Sieve Manganese Oxide : Feasible Material for Hg(II) Remediation ». Dans 5th International Conference on Advanced Materials Science. Switzerland : Trans Tech Publications Ltd, 2023. http://dx.doi.org/10.4028/p-03m8d0.

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Manganese-oxide material prepared by simple sol-gel method was used as an adsorbent of Hg(II) in aqueous solution. X-ray diffraction pattern and Raman spectroscopy were conducted to prove the cryptomelane crystal. The Hg(II) adsorption behavior of the synthesized material well obeyed kinetic models of pseudo-second-order and Elovich equations indicating a chemisorption from the collected kinetic parameters. 500 mgHg2+/gcryptomelane of equilibrium uptake capacity from pseudo-second-order and 7.87x103 mgHg2+/gcryptomelane/day of initial adsorption rate from the Elovich model were obtained for adsorption of Hg2+ cation over cryptomelane adsorbent. Desorption constant of 0.018 gcryptomelane/mgHg is a significant small value, in comparison to initial adsorption rate, proposing a possible chemisorption for remediation of Hg(II) on cryptomelane structure.
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Clifton, Rebecca L., Carlos A. Rios Perez, Rachel Naylor et Carlos Hidrovo. « Characterization of Ion Transport and -Sorption in a Carbon Based Porous Electrode for Desalination Purposes ». Dans ASME 2012 10th International Conference on Nanochannels, Microchannels, and Minichannels collocated with the ASME 2012 Heat Transfer Summer Conference and the ASME 2012 Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/icnmm2012-73183.

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New and more efficient water desalination technologies have been a topic of incipient research over the past few decades. Although much of the attention and efforts have focused on the improvement of membrane-based desalination methods such as reverse osmosis, the development of new high-surface area carbon-based-electrode materials have brought substantial interest towards capacitive deionization (CDI), a novel technique that uses electric fields to separate the ionic species from the water. Part of the new interest on CDI is its ability to store and return a fraction of the energy used in the desalination process. This characteristic is not common to other electric-field-based desalination methods such as electro-deionization (EDI) and electro-dialysis reversal (EDR) where none of the input energy is recoverable. This paper presents work conducted to analyze the energy recovery, thermodynamic efficiency, and ionic adsorption/desorption rates in a CDI cell using different salt concentration solutions and various flow-rates. Voltage and electrical current measurements are conducted during the desalination and porous electrode regeneration processes and used to evaluate the percentage of energy recovery.. Salinity measurements of the inflow and outflow stream concentrations using conductivity probes, alongside the current measurements, are used to calculate ion adsorption/desorption efficiencies. Correlation of these measurements with an analytical species transport model provides information about the net ionic adsorption/desorption rates in non-saturated-carbon-electrode scenarios. The results show a strong dependence of the net electrical energy requirements with the number of carbon electrodes regeneration cycles. Finally, a non-dimensional number that compares the convective and electro-kinetic transport times is presented. The energy requirements and adsorption/desorption rates analyses conducted for this water-desalination process could be extended to other ion-adsorption applications such as the re-process of spent nuclear fuels in a near future.
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Bozso, Ferenc. « Electron and Photon-Beam Induced Thin-Film Growth ». Dans The Microphysics of Surfaces : Beam-Induced Processes. Washington, D.C. : Optica Publishing Group, 1991. http://dx.doi.org/10.1364/msbip.1991.ma1.

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The small dimensions of novel electronic and optoelectronic device structures and their abruptly and unconventionally changing material compositions require high levels of spatial and kinetic control of the surface chemical reactions which are involved in the materials' growth or modification. These requirements exclude high temperature processes based on thermally activated chemical reactions. Directed energetic beams (electrons, photons, ions), however, can induce reactions at low temperatures, as well as provide for spatial and kinetic control in microfabrication processes. Electrons and photons of sufficient energy can cause fragmentation and desorption of adsorbed molecules or fragments of them, by inducing electronic excitations to dissociative states1. The surface species after such excitations are mostly of highly reactive radical character, which readily react with the substrate and with other radical or molecular species in the adsorbed layer. The formation of such reactive surface species in a controlled way can provides a basis for non-thermal selective area film growth.
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Devarakonda, Maruthi, Russell Tonkyn, Diana Tran, Jong H. Lee et Darrell Herling. « Modeling Competitive Adsorption in Urea-SCR Catalysts for Effective Low Temperature NOx Control ». Dans ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-39977.

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Although the SCR technology exhibits higher NOx reduction efficiency over a wider range of temperatures among the lean NOx reduction technologies, further improvement in low-temperature performance is required to meet the future emission standards and to lower the system cost. In order to improve the catalyst technologies and optimize the system performance, it is critical to understand the reaction mechanisms and catalyst behaviors with respect to operating conditions. For example, it is well known that the ammonia coverage on catalyst surface is critical for NOx reduction efficiency. However, the level of ammonia storage is influenced by competitive adsorption by other species, such as H2O and NO2. Moreover, hydrocarbon species that slip through the upstream DOC during the cold-start period can also inhibit the SCR performance, especially at low temperatures. Therefore, a one-dimensional kinetic model that can account for the effects of such competitive adsorption has been developed based on steady state surface isotherm tests on a commercial Fe-zeolite catalyst. The model is developed as a C language S-function and implemented in Matlab/Simulink environment. Rate kinetics of adsorption and desorption of each of the adsorbents are determined from individual adsorption tests and validated for a set of test conditions that had all the adsorbents in the feed gas. Using the competitive adsorption model, a kinetic model for standard-SCR reaction involving NH3 and H2O is developed and validated.
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Rapports d'organisations sur le sujet "Desorption kinetic"

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Ferrizz, Robert Matthew. Erbium hydride thermal desorption : controlling kinetics. Office of Scientific and Technical Information (OSTI), août 2007. http://dx.doi.org/10.2172/920769.

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Cerjan, C., et J. Ellsworth. An expanded kinetics model describing injector region desorption. Office of Scientific and Technical Information (OSTI), août 2020. http://dx.doi.org/10.2172/1657681.

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Hemminger, John C., Jr McIver et Robert T. Kinetics of Surface Reactions Studied by Laser Desorption with FTMS detection. Fort Belvoir, VA : Defense Technical Information Center, janvier 1992. http://dx.doi.org/10.21236/ada248412.

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Dinh, L., et M. Balooch. Desorption Kinetics of H2O, H2, CO, and CO2 from Silica Reinforced Polysiloxane. Office of Scientific and Technical Information (OSTI), août 1999. http://dx.doi.org/10.2172/792649.

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Koyanagi, Takaaki, Hanns Gietl et Ben Garrison. Kinetics of Hydrogen Desorption from Yttrium Hydride : The Development of Material Characterization Methods. Office of Scientific and Technical Information (OSTI), septembre 2021. http://dx.doi.org/10.2172/1824953.

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Dinh, L., M. Balooch et J. D. LeMay. Desorption Kinetics of H2O from Cab-O-Sil-M-7D and Hi-Sil-233 Silica Particles. Office of Scientific and Technical Information (OSTI), janvier 2000. http://dx.doi.org/10.2172/792441.

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Andy Miller. Upscaling of Long-Term U9VI) Desorption from Pore Scale Kinetics to Field-Scale Reactive Transport Models. Office of Scientific and Technical Information (OSTI), janvier 2009. http://dx.doi.org/10.2172/1042469.

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Steefel, Carl I., Li Li, J. A. Davis, G. P. Curtis, B. D. Honeyman, D. B. Kent, M. Kohler, D. R. Rodriguez, K. J. Johnson et A. Miller. Upscaling of Long-Term U(VI) Desorption from Pore Scale Kinetics to Field-Scale Reactive Transport Models. Office of Scientific and Technical Information (OSTI), juin 2006. http://dx.doi.org/10.2172/896179.

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Dang, Yuhong, V. M. Malhotra et K. S. Vorres. Effects of particle size on the desorption kinetics of water from Beulah-Zap lignite coal : Differential scanning calorimetry results. Office of Scientific and Technical Information (OSTI), mars 1996. http://dx.doi.org/10.2172/206632.

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Bertsch, Paul M., Andrew Sowder et Brian Jackson. Linking Chemical Speciation, Desorption Kinetics, and Bioavailability of U and Ni in Aged-Contaminated Sediments : A Scientific Basis for Natural Attenuation and Risk Assessment. Office of Scientific and Technical Information (OSTI), juin 2003. http://dx.doi.org/10.2172/836464.

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