Soil, model

Sanders PF, Seiber JN. 1983. A chamber for measuring volatilization of pesticides from model soil and water disposal systems. Chemosphere 12 999-1012. 

Hodapp DM, Winterlin W. 1989. Pesticide degradation in model soil evaporation beds. Bull Environ Contam Toxicol 43 36-44. 

J. S. Gcelhoed. L. J. M. Sipko, and G. R. Findernegg, Modelling zero sink nutrient uptake by roots with root hairs from. soil compari.son of two models. Soil Sci. 162 544 (1997). 

D. J. Greenwood and T. V. Karpinets, Dynamic model for the effects of K-fertilizer on crop growth, K-uptake and soil-K in arable cropping I. Description of the model. Soil Use Mift. i34 19, (1997). 

H. Van der Werf and W. Verstraete, Estimation of active soil microbial biomass by mathematical analysis of respiration curves development and verification of the model. Soil Biol. Biochem. 19 252 (1987). 

H.H. Cheng, Pesticides in the Soil Environment Processes, Impacts and Modeling, Soil Science Society of America, Madison, WI (1990). 

In the area of transport-type models, soil/water systems have been a primary area of development. The Hydrologic Simulation Program (18) described in the paper by Johanson simulates chemical movement and transformation in runoff, groundwater and surface water in contact with soil or sediments. 

DBCP. The predictions suggest that DBCP is volatile and diffuses rapidly into the atmosphere and that it is also readily leached into the soil profile. In the model soil, its volatilization half-life was only 1.2 days when it was assumed to be evenly distributed into the top 10 cm of soil. However, DBCP could be leached as much as 50 cm deep by only 25 cm of water, and at this depth diffusion to the surface would be slow. From the literature study of transformation processes, we found no clear evidence for rapid oxidation or hydrolysis. Photolysis would not occur below the soil surface. No useable data for estimating biodegradation rates were found although Castro and Belser (28) showed that biodegradation did occur. The rate was assumed to be slow because all halogenated hydrocarbons degrade slowly. DBCP was therefore assumed to be persistent. 

Goldberg, S. Reanalysis of boron adsorption on soils and soil minerals using the constant capacitance model. Soil Sci Soc Am J 1999 63 823-829. 

By modelling soil erosion, Pimentel et al. (1995) showed that 30% of the world s arable land was lost from 1955 to 1995. As losses continue by 10... 

Quantification of changes in soil carbon dynamics, including SOM turnover rate and distribution of SOC with depth, is therefore critical for determining carbon storage in soils and for modeling soil carbon cycling. 

Schenker et al (2008a) evaluated the CliMoChem model soil concentrations against observed concentrations from various sediment and soil studies. Their compilation of observed data was used to evaluate MPI-MCTM soil results. 

Parker, D.R., W. A. Norvell and R. L. Chaney, 1995, GEOCHEM-PC, a chemical speciation program for IBM and compatible personal computers. In R. H. Loep-pert, A. P. Schwab and S. Goldberg (eds.), Chemical Equilibrium and Reaction Models. Soil Science Society of America Special Publication 42,253-269. 

There is, however, little systematic understanding of the factors that control preservation for the wide range of materials encountered archae-ologically, and virtually nothing in the way of predictive models. Soil pH (crudely speaking, acidity see Section 13.1) and Eh (redox potential, or... 

A comparison has been made of the efficiencies of conventional and ultrasonically assisted pollutant extraction procedures using model soil samples (granular pieces of brick) which had been deliberately contaminated with copper oxide at 51 ppm [50]. Analysis of the brick particles after 30 min sonication on a Vibrating Tray [51] revealed an average reduction in copper content to 31 ppm, a reduction of about 40%. Using a conventional mechanically shaken tray for the same time period the residual contamination was 48 ppm representing a reduction of only 6% (Tab. 4.6). 

Celis, R., Koskinen, W.C., Hermosin, M.C., and Cornejo, J. Sorption and desorption of tridimefon by soils and model soil colloids, J. Agric. Food Chem., 47(2) 776-781, 1999. 

Enfield, C.G. and Yates, S.R. Organic chemical transport in groundwater, in Pesticides in the Soil Environment Processes, Impacts, and Modeling, Soil Science of Society of America, Cheng. H.H., Ed. (Madison. WI SSSA, 1990), pp. 271-302. 

LaFleur, K.S. Sorption of pesticides by model soils and agronomic soils rates and equilibria, SoilSci., 127(2) 94-101, 1979. 

In this paper, the volatilization of five organophosphorus pesticides from model soil pits and evaporation ponds is measured and predicted. A simple environmental chamber is used to obtain volatilization measurements. The use of the two-film model for predicting volatilization rates of organics from water is illustrated, and agreement between experimental and predicted rate constants is evaluated. Comparative volatilization studies are described using model water, soil-water, and soil disposal systems, and the results are compared to predictions of EXAMS, a popular computer code for predicting the fate of organics in aquatic systems. Finally, the experimental effect of Triton X-100, an emulsifier, on pesticide volatilization from water is presented. 

A simple environmental chamber is quite useful for obtaining volatilization data for model soil and water disposal systems. It was found that volatilization of low solubility pesticides occurred to a greater extent from water than from soil, and could be a major route of loss of some pesticides from evaporation ponds. Henry s law constants in the range studied gave good estimations of relative volatilization rates from water. Absolute volatilization rates from water could be predicted from measured water loss rates or from simple wind speed measurements. The EXAMS computer code was able to estimate volatilization from water, water-soil, and wet soil systems. Because of its ability to calculate volatilization from wind speed measurements, it has the potential of being applied to full-scale evaporation ponds and soil pits. 

Lopez-Capel, E., Sohi, S., Gaunt, J. L., and Manning, D. A. C. (2005b). Use of thermogravimetry-differential scanning calorimetry to characterize modelable soil organic matter fractions. Am. J. Soil Sci. Soc. 69, 3192-3198. 

Studies on sorption of triazines by individual soil constituents and by model sorbents have been very helpful in evaluating sorption mechanisms and in assessing the potential contribution of various constituents to triazine sorption by soils. However, intimate associations between organic substances, silicate clays, and oxyhydroxide materials modify the sorptive properties of the individual constituents. Associations between soil constituents influence soil properties - such as pH, specific surface area, and functional group availability - which in turn influence triazine sorption behavior. For instance, atrazine and simazine sorption behavior is different for synthetic mixtures of model soil... 

LaFleur, K.S. (1979a). Sorption of metribuzin herbicide by model soils and agronomic soils Rates and equilibria. Soil Sci., 127 51-55. 

Jardine, P. M., Parker, J. C., and Zelazny, L. W. (1985b). Kinetics and mechanisms of aluminum adsorption on kaolinite using a two-site nonequilibrium transport model. Soil Sci. Soc. Am. J. 49, 867-873. 

Alveteg M, Sverdrup H, Warfvinge P. 1995. Developing a kinetic alternative in modeling soil aluminum. Water Air Soil Pollut 79 377-389. 

Abstract An approach based on the theory of mixtures with the concept of molar volume fractions and on the basic principles of continuum mechanics and macroscopic thermodynamics is introduced to model soil freezing of solute saturated soil. 

Murray, K. and Linder, P.W. (1983) Fulvic acids structure and metal binding. I. A random molecular model./. Soil Sci., 34, 511-523. 

Sposito, G., Bingham, F.T., Yadav, S.S. and Inouye, C.A. (1982) Trace metal complexation by fulvic acid extracted for sewage sludge II. Development of chemical models. Soil Sci. Soc. Am.J., 46, 51—56. 

In common with other sequential extraction procedures, the BCR scheme suffers from a degree of non-specificity (Whalley and Grant, 1994 Coetzee et d., 1995) and redistribution of analytes during extraction (Raksasataya et d., 1996). Some success in limiting lead redistribution by addition of cryptand 2.2.2 or nitriloacetic acid to the acetic acid in Step 1 has been reported, but the effectiveness of the complexing agent was found to be strongly dependent on the bulk composition of the model soil system studied (Raksasataya et d., 1997). 

Solid soils are commonly encountered in hard surface cleaning and continue to become more important in home laundry conditions as wash temperatures decrease. The detergency process is complicated in the case of solid oily soils by the nature of the interfacial interactions of the surfactant solution and the solid soil. An initial soil softening or "liquefaction", due to penetration of surfactant and water molecules was proposed, based on gravimetric data (4). In our initial reports of the application of FT-IR to the study of solid soil detergency, we also found evidence of rapid surfactant penetration, which was correlated with successful detergency (5). In this chapter, we examine the detergency performance of several nonionic surfactants as a function of temperature and type of hydrocarbon "model soil". Performance characteristics are related to the interfacial phase behavior of the ternary surfactant -hydrocarbon - water system. 

The IRE of the Prism Cell was coated with a layer of hydrocarbon "model soil" in the same way as was done in earlier work with the CIRCLE (5.12). The IRE is withdrawn mechanically from the solution of the hydrocarbon of interest (2-4 wt.% in hexane) at a slow, controlled rate. The hexane flashes off, leaving a layer of hydrocarbon behind. By varying the withdrawal rate and the concentration of the hydrocarbon, layers of varying thicknesses, as judged by the intensity of the bands of the hydrocarbon spectrum, can be obtained. 

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