Tesi: "Soil adsorption"

1

Ward, Philip R. "Generation of water repellence in sands, and its amelioration by clay addition /". Adelaide, 1993. http://web4.library.adelaide.edu.au/theses/09PH/09phw262.pdf.

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2

Reed, Stewart T. "Copper adsorption/desorption characteristics on copper amended soils". Diss., This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-06062008-171512/.

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3

Gusli, Sikstus. "Effect of methods of wetting and rainfall characteristics on crusting and hardsetting of a red-brown earth". Title page, abstract and table of contents only, 1995. http://web4.library.adelaide.edu.au/theses/09PH/09phg982.pdf.

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Includes bibliographical references. The beneficial effects of tillage are often negated in Australian soils by poor aggregate structural stability. If irrigation or rain falls on exposed freshly tilled soil, crusting or harsetting often develops on drying. Rainfall intensity, kinetic energy, rate of wetting, antecedent water content and soil management history have been implicated in aggregate breakdown.

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4

Sandhu, Harjinder. "Sorption of lead and arsenic on soil components and effectiveness of phosphates for remediating lead and arsenic contaminated soils". Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1923.

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Thesis (Ph. D.)--West Virginia University, 2001.
Title from document title page. Document formatted into pages; contains xii, 170 p. : ill. (some col.). Includes abstract. Includes bibliographical references.

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5

Christie, Emma Louise. "Deconstructing adsorption variability : investigating controls on pesticide adsorption in soil and modelling Koc". Thesis, Durham University, 2013. http://etheses.dur.ac.uk/7347/.

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Due to potential environmental risks of pesticides, it is important that the fate of pesticides is known and that safer pesticides are developed in the future. This thesis focused on identifying controls on the Koc of pesticides in soil based on their structural parameters. This thesis also developed quantitative structure-activity relationship (QSAR) models to predict the environmental fate of new pesticides. To understand the controls on Koc, a range of multivariate statistical techniques were used including; principal component analysis, and analysis of variance. Predictive models were created using logistic regression, and multiple linear regression. The study found adsorption of pesticides in soil is controlled by a combination of size and solubility parameters. Logistic regression models were able to predict the adsorption potential of metabolites, relative to their parent based on metabolite structures. This study found that adsorption behaviour of pesticides was fairly specific to different chemical groups. A QSAR model for Koc was constructed for a group of early stage compounds and could predict Koc to just over an order of magnitude. The results of this study have implications for the pesticide development process. If developed further to include a wider range of chemical groups then the models have the potential to reduce the dependence on laboratory tests in the early stages of the development process. However, this study also questions the use of Koc as a predictive parameter and offers alternative solutions to predicting environmental fate of pesticides.

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6

Park, Gi-hyeon. "Spatial and temporal patterns in soil moisture variations in Oklahoma and its comparison with ETA Model". Thesis, The University of Arizona, 2000. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_etd_hy0057_m_sip1_w.pdf&type=application/pdf.

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7

Arthur, Jennifer D., Noah W. Mark, Susan Taylor, J. Šimunek, M. L. Brusseau e Katerina M. Dontsova. "Batch soil adsorption and column transport studies of 2,4-dinitroanisole (DNAN) in soils". ELSEVIER SCIENCE BV, 2017. http://hdl.handle.net/10150/624067.

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The explosive 2,4,6-trinitrotoluene (TNT) is currently a main ingredient in munitions; however the compound has failed to meet the new sensitivity requirements. The replacement compound being tested is 2,4-dinitroanisole (DNAN). DNAN is less sensitive to shock, high temperatures, and has good detonation characteristics. However, DNAN is more soluble than TNT, which can influence transport and fate behavior and thus bio-availability and human exposure potential. The objective of this study was to investigate the environmental fate and transport of DNAN in soil, with specific focus on sorption processes. Batch and column experiments were conducted using soils collected from military installations located across the United States. The soils were characterized for pH, electrical conductivity, specific surface area, cation exchange capacity, and organic carbon content. In the batch rate studies, change in DNAN concentration with time was evaluated using the first order equation, while adsorption isotherms were fitted using linear and Freundlich equations. Solution mass-loss rate coefficients ranged between 0.0002 h(-1) and 0.0068 h(-1). DNAN was strongly adsorbed by soils with linear adsorption coefficients ranging between 0.6 and 6.3 L g(-1), and Freundlich coefficients between 1.3 and 34 mg(1-n) L-n kg(-1). Both linear and Freundlich adsorption coefficients were positively correlated with the amount of organic carbon and cation exchange capacity of the soil, indicating that similar to TNT, organic matter and clay minerals may influence adsorption of DNAN. The results of the miscible-displacement column experiments confirmed the impact of sorption on retardation of DNAN during transport. It was also shown that under flow conditions DNAN transforms readily with formation of amino transformation products, 2-ANAN and 4-ANAN. The magnitudes of retardation and transformation observed in this study result in significant attenuation potential for DNAN, which would be anticipated to contribute to a reduced risk for contamination of ground water from soil residues.

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8

Ward, Philip R. "Generation of water repellence in sands, and its amelioration by clay addition / Philip R. Ward". Thesis, Adelaide, 1993. http://hdl.handle.net/2440/21659.

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9

Sengdy, Boua. "Modelling cadmium and zinc adsorption by a wetland soil". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ40440.pdf.

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10

Fu, Yong 1948. "Solid activity coefficients of phosphate adsorbed by soil". Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276722.

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The data of 14 soils were used to compute the ion activity product (IAP), the ratio of the ion activity product and to the solubility product (Ksp) of the pure minerals (IAP/Ksp) and to estimate the solid activity coefficients (SAC) of the soil components. The value of IAP and SAC of AlPO4 differs from soil to soil and increases with increasing P added to soil in acid soils and for calcium phosphate in basic soils. Magnesium apparently did not cause P adsorption or precipitation in the soils studied. The SAC of aluminum phosphate ranged from 10 to 10000 in acid soils. The mole fraction of the total phosphate in soil seemed to be a more satisfactory basis for calculating the concentration of the solid phase than was measurements of the available phosphate.

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11

Xiao, Baohua. "The effects of soil organic matter heterogeneity on equilibrium sorption by soils and sediments /". Philadelphia, Pa. : Drexel University, 2004. http://dspace.library.drexel.edu/handle/1860/305.

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12

Jabeen, Nusrat. "The adsorption of herbicides and pesticides on clay and soil". Thesis, Lancaster University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387470.

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13

Yiannakakis, Alexandros Emmanuel 1959. "Adsorption/desorption of phenols on the Pima clay loam soil". Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276709.

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Abstract (sommario):

A linear distribution isotherm described the sorption/desorption of four phenols on the Pima clay loam soil. The linear distribution coefficients for 2,4-dichlorophenol, 2-chlorophenol, phenol and 2,4,6-trichlorophenol were 3.61, 2.93, 0.87, and 0.79. Ionization of the phenols affected their relative distribution order. Hydrogen bonding of phenols to exposed mineral sites accounted for the greater measured sorption than was predicted. The effect of solid concentration on the distribution of phenols was tested over a 10-fold soil/solution range. When a log transformation was performed on the data, a highly significant inverse relationship existed between the distribution of phenols and the soil/solution ratio. A 3-fold increase in the dissolved organic carbon in solution was associated with the decrease in the distribution coefficient. A 3-fold increase in the fraction organic carbon in the soil occurred when dry sludge solids were added to the Pima soil. A substantial increase in the dissolved organic carbon in solution was associated with the addition of sludge solids to the soil. (Abstract shortened with permission of author.)

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14

Killen, Mark Albert. "A physically based analytical model to predict infiltration under surge irrigation". Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184379.

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A significant advantage attributed to surge flow irrigation is that for the same volume of water applied the stream will advance farther along the furrow than with continuous flow. This potentially will reduce runoff and deep percolation which will improve uniformity and application efficiency where this advance phenomenon holds. The mechanism for improvement in advance time has generally been ascribed to surface sealing and surface layer consolidation. However, these phenomena do not satisfactorily explain improved advance times in sandy soils. Widely used infiltration equations which require the determination of empirical coefficients are unsatisfactory as predictors of infiltration conditions of intermittent wetting. The Green-Ampt model and a simple redistribution model are combined into an analytical model to predict infiltration under surge irrigation. The model results are compared to infiltration tests on soil columns of three soils of different soil textures. Also the model and the experimental results from the soil columns are compared to predictions made by two numerical solutions of the Richard's equation. One of the numerical models includes the effect of hysteresis by the use of Mualem's model to predict the variation of moisture content with potential, the other numerical model neglects the effect of hysteresis. A comparison of the analytical and the numerical models shows good agreement in their predictions for the soils and surge cycles tested. A comparison of predictions made by all three models shows good correlation to the experimental results. Although the number of tests done on the analytical model were limited it appears to be nearly as good a predictor of infiltration as the numerical models. The greatest strength of the analytical model is that while the numerical models took many hours to do a single run, the analytical model took only a few minutes. Both model and experimental results indicate that there was no reduction in infiltration rates or volumes infiltrated with intermittent as compared to continuous wetting. Thus the reduction in hydraulic gradient is not a factor in the reduced infiltration observed by others.

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15

Dye, Colin. "Phosphate adsorption by ferric oxide gel, the effect of organic anions and the usefulness of some models for interpreting the adsorption data". Thesis, University of Reading, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.304850.

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16

Neitsch, Susan Lynn. "Adsorption and desorption of atrazine on a melamine-based soil amendment". Thesis, Texas A&M University, 2004. http://hdl.handle.net/1969.1/567.

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Adsorption kinetics and adsorption-desorption of atrazine on organoclay composites prepared with the surfactant 6-piperazin-1-yl-N,N'-bis-(1,1,3,3-tetramethyl-butyl)-(1,3,5)triazine-2,4-diamine and Houston Black clay were studied using the indirect batch equilibration procedure. The organoclay composites sorbed significantly more atrazine than the Houston Black clay. Adsorption equilibrium was reached after 72 h for the organoclay composites. Atrazine adsorption isotherms were described by linear partitioning. The Koc values ranged from 605 to 5271 L kg-1 for the organoclay composites compared to a value of 41 L kg-1 for the Houston Black clay. The organoclay composite containing 20% surfactant on a total weight basis provided the most efficient adsorption of atrazine, although organoclay composites containing much lower amounts of surfactant also adsorbed significant amounts of atrazine. An average of 11% of sorbed atrazine was released during desorption. Characterization of desorption products showed only atrazine molecules being released from the organoclay composites.

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17

Burgos, William David. "Reversible and irreversible adsorption of naphthalene and α-naphthol to soil". Diss., Virginia Tech, 1995. http://hdl.handle.net/10919/38186.

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Experiments were performed with naphthalene and a-naphthol to compare the processes involved in the sorption of a polycyclic aromatic hydrocarbon (PAH) and its metabolite, respectively, and to assess the bioavailability of these two compounds adsorbed to two sandy soils with different organic carbon contents. Adsorption conditions were varied to estimate the extent that biologically-mediated and chemically-induced oxidative coupling, and rate-limited diffusive processes contributed to the apparent irreversible adsorption of these compounds. The purposes of this research were to: (1) investigate the processes which cause the irreversible adsorption of organic contaminants to soil~ (2) gauge the impact that these different adsorption processes have on the bioavailability of sorbed contaminants; and, (3) evaluate the environmental significance of these processes in soils and the subsurface. This dissertation has been prepared as three separate articles for publication in peer reviewed journals. The first article serves as a literature review in evaluating the significance of oxidative coupling reactions in soil and subsurface environments. This review concludes that oxidative coupling of organic contaminants may be important in soils and could be stimulated as a viable remediation strategy. For subsurface systems oxidative coupling appears much more limited, however, engineered systems could be developed to enhance this process. The second article presents experimental results used to quantify the individual processes involved in the irreversible adsorption of naphthalene and a-naphthol. This article concludes that both biological and chemical catalysts are important in promoting irreversible adsorption reactions, and that once the partial oxidation of a PAH occurs, oxidative coupling can become a significant process affecting contaminant fate. The third and final article examines the effect of different adsorption processes on the subsequent bioavailability of sorbed naphthalene and anaphthol, and concludes that the biodegradation of naphthalene and α-naphthol adsorbed to both the soils tested was controlled by the rate of desorption and the reversibility of the adsorption process.
Ph. D.

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18

Burgos, William David. "Reversible and irreversible adsorption of naphthalene and [alpha]-naphthol to soil /". This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-06062008-162414/.

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19

PULS, ROBERT WILLIAM. "ADSORPTION OF HEAVY METALS ON SOIL CLAYS (KAOLINITE, CADMIUM, MONTMORILLONITE, ZINC)". Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/183889.

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Metal cation adsorption is the predominant chemical mechanism governing the attenuation of toxic metal movement in soils. Clay minerals are the primary adsorbent surfaces in soils due to their ubiquitous nature and large reactive surface area. This study examined the relative affinity of the metals cadmium, nickel and zinc for the clay minerals kaolinite and montmorillonite. The influence which different mineral adsorbents and different complexing ligands in solution have on the adsorption of metal ions was assessed using the Hard-Soft Acid-Base Principle as a theoretical framework for predicting the maximum extent of adsorption and rate of adsorption. The HSAB principle is that hard bases prefer to complex hard acids and soft bases prefer to complex soft acids. The hypothesis that initiated these investigations was that the hard-soft character of mineral surfaces is due to their surface functional groups and can be measured using metal cation adsorption selectivity experiments where pH and complex ion formation are controlled. When complex ion formation in aqueous solution was minimized (i.e. in Ca(ClO₄)₂), adsorption decreased in the order of decreasing softness, CD > Zn > Ni for both clay minerals. Montmorillonite behaved as a slightly harder Lewis base than kaolinite, sorbing the harder Ni and Zn ions to a greater extent than Cd, although both minerals behaved as soft Lewis bases. In the presence of chloride and sulfate ligands, adsorption sequences changed and reflected results from typical soil solution studies. In some cases the adsorption sequences can be explained using the HSAB principle together with computer speciation data and this approach merits further consideration and research. Adsorption over time and calculated adsorption rate constants were generally consistent with equilibrium selectivity data. Adsorption rates decreased in the order Cd > Zn > Ni in Ca(ClO₄)₂ for both clay minerals. The adsorption curves reflect a two-step adsorption process involving a rapid exchange-type reaction followed by a much slower adsorption involving diffusion into the crystal or alteration of the surface through the formation of a new solid phase involving the adsorbed ions.

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20

Don-Pedro, Esther A. "The effects of soil properties and clay minerals on the bioremediation of soils contaminated with pentachlorophenol". Akron, OH : University of Akron, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=akron1126632988.

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Thesis (M.S.)--University of Akron, Dept. of Geology, 2005.
"August, 2005." Title from electronic thesis title page (viewed 11/29/2005) Advisor, Annabelle Foss; Committee members, Teresa Cutright, Ira Sasowsky; Department Chair, John Szabo; Dean of the College, Charles B. Monroe; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.

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21

Sekhon, Bharpoor Singh. "Modeling of soil phosphorus sorption and control of phosphorus pollution with acid mine drainage floc". Morgantown, W. Va. : [West Virginia University Libraries], 2002. http://etd.wvu.edu/templates/showETD.cfm?recnum=2530.

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Thesis (Ph. D.)--West Virginia University, 2002.
Title from document title page. Document formatted into pages; contains xiv, 210 p. : ill. (some col.). Includes abstract. Includes bibliographical references.

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22

Wang, Yu-Hsing. "Attenuation in soils and non-linear dynamic effects". Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/19582.

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23

Miropolskiy, Reuven. "The effects of soil properties on the sorption of selected cephalosporin antibiotics". Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Thesis/Fall2009/r_miropolskiy_120109.pdf.

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Thesis (M.S. in chemical engineering)--Washington State University, December 2009.
Title from PDF title page (viewed on Jan. 20, 2010). "Department of Chemical Engineering and Bioengineering." Includes bibliographical references (p. 63-65).

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24

Jeong, Chang-Yoon. "Modelling metal competition for adsorption sites on humic acid". Thesis, University of Nottingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389363.

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25

Gu, Baohua. "An investigation of the effect of organic soil constituents on boron adsorption". Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/25886.

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The preparation and synthetic utility of a number of structurally interesting donor-acceptor reagents is described. It has been found that protonative deconjugations of geometrically isomeric β-trimethyl-stannyl-α,β-unsaturated esters are highly stereospecific. Thus, treatment of the esters (131) and (137) with lithium diisopropylamide in THF or THF-HMPA followed, in each case, by transfer of the resultant solution to a cold (-98°C) solution of acetic acid in ether, provided exclusively the alkyl 3-trimethylstannyl-3-alkenoates (167) and (173), respectively. Ethyl (Z) and (E)-3-trimethylstannyl-3-pentenoates were converted into the chlorides (99) and (100), respectively. Transmetalation of (99) afforded (204), which was transformed into the Grignard reagent (218) . Both (204) and (218) serve effectively as conjunctive reagents which are synthetically equivalent to the (E)-d³,a⁵-2-pentene synthon (200). For example, copper(I)-catalyzed conjugate addition of (218) to enones and subsequent intramolecular alkylation of the resultant products form the basis of a new (Z)-ethylidenecyclopentane annulation process [(220) → (222)]. Interestingly, although transmetalation of (100) also occurred smoothly, the resultant lithio reagent (207) self-annihilated rapidly even at low temperatures to give ethylidene-cyclopropane. The annulation method described above played a key role in short syntheses of (±)-oplopanone (257), (±)-8-epi-oplopanone (323), and (±)-anhydro-oplopanone (258). Thus (Z)-ethylidenecyclopentane annulation of 4-isopropyl-2-cyclohexen-l-one provided the bicyclic ketone (307). Suitable functional group manipulations transformed (307) into (±)-(257), (±)-(323), and (±)-(258). Reaction of 1-alkyn-3-ols with Me₃SnCu.Me₂S-MeOH, [Me₃SnZn(t-Bu)₂]Li-CuCN, or [Me3SnZnEt2]Li-CuCN provided, in varying ratios, the vinylstannanes (109) and (339). Orthoester Claisen rearrangement of (109) and (339) afforded the esters (357) and (363), respectively. Ethyl (Z)-4-trimethylstannyl-4-hexenoate was transformed into the chloride (370). Compound (370) is a convenient precursor of reagents (371) and (374) which are synthetically equivalent to the (E)-d³,a⁶-2-hexene synthon (379). For instance, the Grignard reagent (374) served as a pivotal species in the development of a new six-membered annulation method [(101) → (380)]. [See Thesis for Diagrams]
Land and Food Systems, Faculty of
Graduate

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26

Jacinthe, Pierre-Andre. "Adsorption of the nitrification inhibitors nitrapyrin and dicyandiamide by soil humic substances". Virtual Press, 1990. http://liblink.bsu.edu/uhtbin/catkey/722445.

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Abstract (sommario):

Adsorption of the nitrification inhibitors dicyandiamide (DCD) and nitrapyrin (2-chloro-6(trichloromethyl)-pyridine) on humic acid (HA) and fulvic acid (FA) extracted from five Indiana soils was studied. Ten mg of HA or FA were suspended in aqueous solutions (10 ml) of either DCD (5,10, 20, 40 and 80 ug ml-1) or nitrapyrin (2,4,6,8,12 ug ml-1). The amount of nitrification inhibitor absorbed was evaluated after shaking the suspension of DCD for 48 h or nitrapyrin for 24 h. Infrared spectra of the nitrification inhibitor-humic material complexes were recorded. The results indicated that FA adsorbed more DCD than HA, and HA was a better adsorbent for nitrapyrin. Correlation between Freundlich K values and organic carbon content of HA and FA was not statistically significant, indicating a slight contribution of hydrophobic forces in the adsorption of DCD and nitrapyrin. The infrared spectra provided evidence that adsorption occurred predominantly through an ionic bonding mechanism involving the protonated amino group of DCD or the nitrogen of the pyridine ring of nitrapyrin and the negative functional groups of the humic materials.
Department of Natural Resources

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27

Mewett, John University of Ballarat. "Electrokinetic remediation of arsenic contaminated soils". University of Ballarat, 2005. http://archimedes.ballarat.edu.au:8080/vital/access/HandleResolver/1959.17/12797.

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"Arsenic is a common soil contaminant in Australia and worldwide. There is a need to find safe, effective and economic methods to deal with this problem. The soils used in this research were collected from central Victoria. They were contaminated with arsenic by historic gold mining activity or by past sheep dipping practices. This research investigated ten different leaching agents for their effects on three different arsenic contaminated soils. [...] Electrokinetic experiments were conducted on three arsenic contaminated soils. [...] The arsenic in these soils appears to be relatively stable and immobile under oxidising conditions. The soils had a high iron content which assists in the stabilisation of arsenic. This is beneficial with respect to the environmental impact of the arsenic contamination, however, it remains an obstacle to low cost electrokinetic remediation."
Masters of Applied Science

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28

Mewett, John. "Electrokinetic remediation of arsenic contaminated soils". Thesis, University of Ballarat, 2005. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/68354.

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Abstract (sommario):

"Arsenic is a common soil contaminant in Australia and worldwide. There is a need to find safe, effective and economic methods to deal with this problem. The soils used in this research were collected from central Victoria. They were contaminated with arsenic by historic gold mining activity or by past sheep dipping practices. This research investigated ten different leaching agents for their effects on three different arsenic contaminated soils. [...] Electrokinetic experiments were conducted on three arsenic contaminated soils. [...] The arsenic in these soils appears to be relatively stable and immobile under oxidising conditions. The soils had a high iron content which assists in the stabilisation of arsenic. This is beneficial with respect to the environmental impact of the arsenic contamination, however, it remains an obstacle to low cost electrokinetic remediation."
Masters of Applied Science

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29

Mewett, John. "Electrokinetic remediation of arsenic contaminated soils". University of Ballarat, 2005. http://archimedes.ballarat.edu.au:8080/vital/access/HandleResolver/1959.17/14633.

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Abstract (sommario):

"Arsenic is a common soil contaminant in Australia and worldwide. There is a need to find safe, effective and economic methods to deal with this problem. The soils used in this research were collected from central Victoria. They were contaminated with arsenic by historic gold mining activity or by past sheep dipping practices. This research investigated ten different leaching agents for their effects on three different arsenic contaminated soils. [...] Electrokinetic experiments were conducted on three arsenic contaminated soils. [...] The arsenic in these soils appears to be relatively stable and immobile under oxidising conditions. The soils had a high iron content which assists in the stabilisation of arsenic. This is beneficial with respect to the environmental impact of the arsenic contamination, however, it remains an obstacle to low cost electrokinetic remediation."
Masters of Applied Science

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30

Robinson, Kevin G. "Influence of organic matter on the sorption and bioavailability of 2,4,6-trichloro-(¹⁴C)-phenol". Diss., This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-08082007-114313/.

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31

Jones, Mary Pletsch. "Evaluating Nutrient Availability in Low Fertility Soils With Resin Capsules and Conventional Soil Tests". BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/3049.

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Abstract (sommario):

Commonly used soil analysis and resin capsule procedures are used to assess nutrient status in fertile soils, but their validity in semi-arid ecosystems is unknown. Three studies were performed to assess resin capsule effectiveness in semi-arid ecosystems. An incubation study was completed in which loamy sand and sandy clay loam soils were treated with rates of N, P, Fe and Zn. Each soil treatment was implanted with a resin capsule and incubated for 60 or 120 days. Resin capsules reflected NH4-N and P fertilizer at low rates in the loamy sand. NO3-N reflected rates in both soils, but did not reflect Fe or Zn application. Resin capsule NH4-N was a better indicator than KCl-extractable NH4-N, but resin capsule NO3-N was not as effective as water extraction, and resin capsule P was poor compared to NaHCO3-P. A second study was performed in glasshouse conditions using the incubation study soils. Soils were treated with rates of N, P and resin capsules were placed in pots. Pots were seeded with squirreltail grass (Elymus elymoides) and placed in a glasshouse. Resin capsules were removed at 120 days, soil samples taken, grass harvested and yield measured. Yield and total nutrient removal was correlated to resin NH4-N, marginally related to resin or soil NO3-N, and unrelated to resin P. Yield and total nutrient removal was correlated with application rates and resin NH4-N and NaHCO3-extracted P. The third field study, compared two sites with rates of N and P application were established on clay loam and sandy loam soils. Resin capsule and conventional soil tests for NO3-N, NH4-N and P were measured and plant nutrient status examined. Resin capsules were removed and replaced and soil samples taken every 90 days. Resins P was not related to P application or to plant tissue P but NaHCO3-extracted P was, while resin NO3-N, KCl-extracted NO3-N and NH4-N were correlated to N application and plant N. Soil test P was more effective in predicting P status and bioavailability than resin capsules. Resin NH4-N and NO3-N predicted N status and bioavailability, but soil tests were just as effective in semi-arid conditions.

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32

Forsling, Scott A. "Sorption and biodegradation of phenanthrene in soils". Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-11102009-020357/.

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33

Davis, James Hal 1956, e James Hal 1956 Davis. "Sorption and desorption of benzene and para-xylene on an unsaturated desert soil". Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/291366.

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Abstract (sommario):

A series of bench-scale experiments was carried out to determine the rate and efficiency with which benzene and p-xylene, components of gasoline, could be removed from an unsaturated soil by air stripping. Glass columns, 30 cm in length, were packed with soil and wetted to volumetric moisture contents of 10 and 18 percent. Air saturated with one of the volatile organic compounds (VOCs) was used to load the column. Clean air was used to strip the contaminant from the soil. Benzene and p-xylene concentrations in the soil water and air were reduced four orders of magnitude after a few hours (2-8) of stripping. Benzene was removed faster than p-xylene. Air flow was the rate-limiting step early in the stripping, however slow desorption from the soil became rate-limiting as the stripping progressed. As moisture content increased the rate of removal of both contaminants decreased.

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34

Hasan, Nazmul. "Adequacy of surface diffusion models to simulate nonequilibrium mass transfer in soils". Online access for everyone, 2008. http://www.dissertations.wsu.edu/Thesis/Summer2008/n_hasan_063008.pdf.

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35

McMahon, Claire Louise. "Characteristics and sorption properties of charcoal in soil with a specific study of the charcoal in an arid region soil of Western Australia". University of Western Australia. School of Earth and Geographical Sciences, 2006. http://theses.library.uwa.edu.au/adt-WU2007.0007.

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[Truncated abstract] Fire creates charcoal from the partial burning of biomass which results in a biologically inert form of carbonaceous (non-living) organic matter that, once integrated into soil and sediments, can persist for long periods of time. Charcoal has a large surface area with a high sorptive capacity for organic and inorganic substances. As a repository for metal and non-metal elements charcoal has been given little, if any, attention in the fields of geochemistry, agriculture and environmental monitoring . . . Despite the differences in charcoal surface area, soil charcoal achieved nearly 100% sorption of 0.5 and 5 μg/g Au from 0.03 M NaCl and 0.01M Ca(NO3)2 solution, almost independent of solution pH. At low pH, charcoal sorbed between 10 and 60% of Cu with initial additions of 2 and 20 μg Cu/g. Similarly, between 15 and 40% of Zn was sorbed by charcoal with initial additions of 5 and 40 μg Zn/g. The role of surface area in sorption of elements by charcoal is clearly only one factor that is important. Charcoal aromatic and aliphatic chemical functional groups, which can be distinguished from other forms of organic matter through spectroscopic determination, are also important in charcoal’s capacity to sorb elements. Accumulation of Be, B, Na, Mg, Al, Si, K, Ca, Ti, Mn, Co, Ni, Cu, Se, Mo, Ba, Au and Pb (out of a range of 29 elements) in soil charcoal, above the concentrations in the matrix soil and plant reference charcoal, was confirmed by ICP-MS analysis. Concentrations of V, Mn, Co, Ni, Cu, Mo, Ba, Au, Pb and Bi were higher in soil charcoal than in values quoted for gossans and pisolites in the field area region (Smith and Perdrix, 1983). Higher values of Au in soil charcoal were associated with considerable amounts of included clay minerals and higher values of other elements including Mo, Mn and Fe.

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36

Niemeyer, Antje. "Prozessanalyse mit Hilfe von mathematischen und statistischen Methoden am Beispiel von Ad- und Desorption im Boden /". Aachen : Shaker, 2000. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=009102162&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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37

Paunovic, Irena. "Immobilized metal adsorption chromatography and characterization of copper-binding ligands from soil solution /". Zürich : ETH, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17163.

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38

MacDonald, Elaine. "Aspects of competitive adsorption and precipitation of heavy metals by a clay soil". Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=26406.

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This thesis examines the retention of three heavy metals (Pb, Cu, Zn) on a predominantly illite clay soil initially saturated with calcium and magnesium. The heavy metal retention mechanisms were examined both experimentally, using batch equilibrium and precipitation tests, and analytically, using the geochemical equilibrium speciation model MINTEQA2. Heavy metal retention was examined in both non-competitive (single metal) situations and competitive (multi-metal) situations. A definite adsorption selectivity order of Pb $>$ Cu $ gg$ Zn was established, as has been found by many other researchers. Retention by ion exchange adsorption was observed by comparing the total amount of heavy metals retained to the total amount of initially adsorbed calcium and magnesium released. In most cases, it was found that ion exchange was the dominant retention mechanism, even at neutral equilibrium pH values. The effect of initial heavy metal solution pH on heavy metal retention was explored. A comparison was made between batch equilibrium tests performed with metal solutions adjusted to an initial pH of 3 and tests performed with metal solutions that were not adjusted and thus at a higher initial pH. In many cases it was found that greater overall retention occurred when initial metal solutions were at a pH of 3 as opposed to a higher initial pH. The speciation modelling, when compared to the experimental results, was found to adequately predict heavy metal retention in simple single metal batch equilibrium tests but in more complicated multi-metal scenarios the modelling had limited success.

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39

Langeron, Julie. "Etablissement d’une relation de type structure-propriétés (QSPR) entre les propriétés des pesticides et deux sols de Champagne crayeuse". Thesis, Reims, 2012. http://www.theses.fr/2012REIMS023/document.

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Ces travaux s'inscrivent dans le cadre du contrat d'objectifs AQUAL dont le but est la lutte contre les pollutions diffuses en milieu rural. Ils font également l'objet d'un partenariat avec le programme Phyt'Eau Ref initié par la Chambre Régionale d'Agriculture de Champagne-Ardenne. Ils portent sur la compréhension de la rétention et du transfert des pesticides du sol à la nappe dans les sols champardennais. Deux sols différents de par leur contenu en matière organique et en calcaire ont été choisis pour réaliser l'étude afin d'étudier le comportement des pesticides dans des sols caractéristiques de la région (pH et taux de calcaire élevé). L'étude a été réalisée sur quarante pesticides appartenant à diverses familles chimiques et de propriétés physico-chimiques différentes. L'objectif est d'identifier les propriétés des pesticides gouvernant leur rétention dans les sols puis d'établir une relation de type structure-propriétés (QSPR) permettant la prédiction du coefficient d'adsorption Kd. L'adsorption et le transfert des pesticides ont été étudiés au laboratoire au moyen d'expériences en réacteurs fermés (étude à l'équilibre) et en colonne de sol reconstituées au laboratoire. Le tracé d'isothermes d'adsorption suivi d'une étude statistique a permis d'identifier l'hydrophobicité, la polarisabilité et la solubilité comme les paramètres physico-chimiques majeurs gouvernant la rétention des quarante pesticides étudiés. Des relations à deux paramètres ont été proposées et testées afin de pouvoir prédire le coefficient d'adsorption des pesticides. Enfin, les travaux réalisés en mode dynamique (colonne) ont permis de mettre en évidence que le phénomène de transfert peut être relié à l'adsorption des pesticides et qu'il est possible de passer de l'un à l'autre des paramètres caractérisant ces deux phénomènes par de simples relations permettant ainsi de s'affranchir de lourdes expériences
This work is a part of the multidisciplinary AQUAL research program, which aims at to strive against diffuse pollutions in rural environment. It also took part in the Phyt'Eau Ref program initiated by the “Chambre Régionale d'Agriculture de Champagne-Ardenne”. It deals with the comprehension of retention and transfer of pesticides from soil to groundwaters in Champagne-Ardenne. Two different soils by their organic matter and calcite contents, were chosen to carry out the study in order to evaluate the behavior of pesticides in characteristic soils of the region (pH and calcite content). The study was carried out on forty pesticides from various chemical families and having different physico-chemical properties. The aim was to identify the physico-chemical properties of pesticides governing their retention in soils and then to establish a quantitative structure properties relationship (QSPR) predicting the adsorption coefficient Kd. Adsorption and transfer of pesticides were studied in laboratory through batch experiments (equilibrium study) and soil column reconstituted in laboratory. Adsorption isotherm plot followed by a statistical analysis allowed identifying hydrophobicity, polarisability and solubility as the main physico-chemical parameters correlated to the pesticide retention. Relations combining two of these parameters were proposed and tested in order to predict the pesticide adsorption coefficient. Finally, studies in dynamic mode (column) allowed to evidence that the transfer phenomenon can be correlated to the pesticide adsorption nd that it was possible to go from one to the other parameters describing these two phenomena by simple linear relations, allowing to get rid of onerous experiences

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40

Brennand, Victoria Jane. "The fate and behaviour of surfactants and organic contaminants in sludge amended soils". Thesis, Liverpool John Moores University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313160.

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41

Bednárová, Paula. "Studium mobility vybraných léčiv v přírodních systémech". Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2020. http://www.nusl.cz/ntk/nusl-433483.

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This diploma thesis focuses on interactions of chosen pharmaceuticals with soil and study their mobility. First part is devoted to the characteristics of the most common pharmaceuticals that appear in the environment, specifically antibacterial chemoterapeutics and analgetics. Subsequently, the occurrence of the pharmaceuticals in environment, their sources and effects are described. Further, the work focuses on soil components and soil organic matter. In conclusion of the theoretical part is the description of used analytical method for processing of the results and also the current state of the problematics. In the practical part of the thesis the experiments were made and analyzed and further served for better understanding of adsorption and interactions of chosen pharmaceuticals with soil and humin acids as the main reactive part of the soil.

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42

Msaky, John Joseph. "Adsorption et desorption du cuivre et du zinc dans les sols". Paris 6, 1987. http://www.theses.fr/1987PA066094.

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Conditions experimentales: effet du rapport masse de terre-volume de solution sur la charge electrique de surface solide. Quand il augmente les quantites adsorbees diminuent. La nature et la concentration des ligands mineraux et organiques ainsi que la forme ionique du milieu influencent l'adsorption du metal. L'adsorption du cu et du zn est differente selon le type du sol, le ph du systeme et la nature du cation competiteur. L'etude de la desorption montre que les metaux, une fois adsorbes, ne sont pas facilement desorbes

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43

Frankki, Sofia. "Association of organic compounds to dissolved and particulate natural organic matter in soils /". Umeå : Dept. of Forest Ecology, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/200652.pdf.

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44

Holland, Jonathan Eddison. "Changes in soil physical properties under raised bed cropping /". Connect to thesis, 2006. http://eprints.unimelb.edu.au/archive/00002537.

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45

Taillon, Kate. "Modeling surface complexation relationships in forest and agricultural soil". Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82435.

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The adsorption behaviour of trace metals in soil may provide us with a way to more accurately predict and assess the toxicity of metals in the environment. This thesis reports efforts to apply surface complexation modeling to agricultural and forest soil and to relate model parameters to common soil properties. This study considered Ca, Cd, Cu, Pb and Zn but the methods here could be applied to other metals. In Chapter 2, the surface charge and adsorption behaviour of a set of Ap horizons was characterised using back-titration and batch adsorption techniques. With the objective of simplifying the application of the NICCA model to surface charge and cation adsorption in whole soils the parameters of the NICCA model were related to soil properties (Chapter 3). Four of the six surface charge parameters could be predicted from soil properties and this enabled me to reasonably predict the surface charge of a second group of soils from soil properties. These results suggest that it is possible to make reasonable predictions about the surface charge and adsorption behaviour of a given type of soil using some easily measurable soil properties and a set of generic NICCA adsorption parameters for that soil type. In Chapter 4 this idea is applied to the determination of lime requirement for the agricultural soils.

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46

Bergsten, Joshua. "Sorption and leaching characteristics of heavy metals in artificial soil". Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4617.

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Thesis (M.S.) University of Missouri-Columbia, 2006.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 21, 2007) Includes bibliographical references.

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47

Yusran, Fadly Hairannoor. "Soil organic matter decomposition : effects of organic matter addition on phosphorus dynamics in lateritic soils". University of Western Australia. School of Earth and Geographical Sciences, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0120.

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[Truncated abstract] Relationships between the persistence of organic matter added to soil, the dynamics of soil organic carbon (C) and phosphorus (P) were examined in four experiments on lateritic soils of Western Australia. The main objective was to quantify the release of P following organic matter application in soils which have high P adsorbing capacity. Another objective was to confirm that due to its recalcitrant materials, the effect of peat lasted longer in soil than other sources of organic matter in terms of increasing plant-available P fractions. Three experiments were conducted under glasshouse conditions for various lengths of time, with nine- to twelve-month incubations to investigate these hypotheses. As expected, organic matter with lower C:N ratios than peat (lucerne hay) decomposed more rapidly compared with peat, and the most active mineralisation took place within the first three months of incubation. Soil organic-C (extracted by 0.5 M K2SO4) had a significant positive correlation with P extracted with 0.5 M NaHCO pH 8.53. For a higher application rate (120 ton ha-1), peat was better than wheat straw and lucerne hay in increasing extractable bicarbonate-P concentrations in soil, especially at incubation times up to 12 months. Throughout the experiment, peat was associated with a steady increase in all parameters measured. In contrast to peat, nutrient release from lucerne hay and wheat straw was rapid and diminished over time. There was a tendency for organic-C (either in the form of total extractable organic-C or microbial biomass-C) to steadily increase in soil with added peat throughout the experiment. Unlike wheat straw and lucerne hay, extractable organic-C from peat remained in soil and there was less C loss in the form of respiration. Therefore, peat persisted and sequestered C to the soil system for a longer time than the other source of organic matter. Freshly added organic matter was expected to have a greater influence on P transformation from adsorbed forms in lateritic soils than existing soil organic matter. By removing the existing soil organic matter, the effect of freshly applied organic matter can be determine separately from that of the existing soil organic matter for a similar organic-C content. In order to do this, some soil samples were combusted up to 450° C to eliminate inherent soil organic matter. The release of P was greater when organic-C from fresh organic matter was applied to combusted soils than in uncombusted soils that contained the existing soil organic matter. The exception only applied for parameters related to soil micro-organisms such as biomass-C and phosphatase. For such parameters, new soil organic matter did not create conditions favourable for organisms to increase in activity despite the abundance of organic matter available. More non-extractable-P was formed in combusted soils compared to bicarbonate-P and it contributed to more than 50% of total-P. As for the first experiment, peat also showed a constant effect in increasing bicarbonate extractable-P in the soil

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48

Brooks, George Patrick 1955. "Forced ventilation removal of chlorinated hydrocarbons in layered, unsaturated soil material: A laboratory evaluation". Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/276975.

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Helium tracer experiments were conducted to characterize conservative tracer behavior in a wedge-shaped lysimeter containing alternating layers of unsaturated silty sand, and clay loam. Experiments were conducted with trichloroethylene and 1,1,1-trichloroethane to determine if air stripping in unsaturated soil could be characterized by mass transfer from the sorbed to the liquid to the vapor phase. Batch experiments were conducted to measure liquid--vapor mass transfer. Solid-liquid-vapor mass transfer was characterized by measuring the vapor phase re-equilibration after the air stripping experiment. The Discrete State Compartment model was used to simulate a conservative gas tracer. The results were compared to the helium tracer. Liquid-vapor, and solid-liquid-vapor mass transfer were modeled by fitting simulated data to experimental data. The conservative tracer, and mass transfer models were combined to simulate air stripping in unsaturated soil.

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49

Li, Maolin. "Adsorption characteristics and dynamics of soil organic phosphorus and its significance for plant nutrition /". Beuren ; Stuttgart : Grauer, 2001. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=009665345&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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50

Akram, Muhammad. "A Freundlich-based model for prediction of pH-dependent sulfate adsorption in forest soil". Thesis, KTH, Mark- och vattenteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-173851.

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The period of industrialization after the second World War in Europe released SO2 and NOx by combustion of fossil fuels and contributed the formation of S and N compounds in the forest ecosystem. The Swedish forest soil systems were influenced by emissions of SO2 followed by H2SO4 deposition, consequently the pool of SO42- had increased in the forest ecosystem. This thesis studied SO42- adsorption in a podzolic Bs horizon soils taken from a Swedish forest soil system. The soil samples from five different sampling sites were collected and the results revealed different amounts of adsorbed SO42- in response to changes in equilibrium concentration and pH. This study found that the amount of adsorbed SO42- (mmol/kg) increased with an added equilibrium concentration of SO42- (mmol/l) and with a decreasing pH. This was determined by equilibration experiments. Based on the results a Freundlich-based model was developed to predict the pool of adsorbed SO42- in the soil samples. The model predicted the pool of adsorbed SO42- (mmol/kg) as a function of pH and the equilibrium concentration of SO42- (mmol/l) in the soil solution system. The extended Freundlich model was optimized in three different ways: by use of unconstrained, constrained and simplified two-point calibration. The results showed that the adsorption of sulfate in the Kloten Bs1 and Risbergshöjden B soils was higher as compared to the Tärnsjo B, Österström B, and Risfallet B soils. The coefficient of determination (R2) determined from an unconstrained fit of the extended Freundlich model (with three adjustable parameters) for Risbergshöjden B and Kloten Bs1 were R2 =0.998 and R2=0.993. Nearly as good fits were found in a constrained fit with two adjustable parameters when it was assumed that nearly 2 protons (2 H+) are co-adsorbed with one SO42- ion (Risbergshöjden B; R2=0.997 and Kloten Bs; R2=0.992). The simplified two-point calibration with two adjustable parameters showed similar parameter values for all most soils and was considered the best optimization method of extended Freundlich model, especially as it requires only limited input data.

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Tesi sul tema "Soil adsorption"

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