Transfer Coefficient Research Articles

Mass‐Transport‐Corrected Transfer Coefficients: A Fully General Approach

AbstractThe transfer coefficient (or, equivalently, the Tafel slope) is an experimentally measurable parameter defined as the change in the logarithm of the current density as a function of the applied potential, where the current density has been corrected ( ) for changes in the concentration of the reagent at the interface. For some electrode geometries (such as the rotating disc or a micro hemispherical electrode) where the electroactive interface is uniformly accessible and the mass‐transport is at steady‐state, these changes in concentration can be corrected for analytically. Correcting for the depletion of the reagent significantly increases the range over which Tafel analysis can be used to accurately yield information regarding the electron‐transfer process. The important question arises, therefore, for non‐uniformly accessible electrodes or for a system not at steady state, such as often encountered with disc electrodes, how can the experimentally measured electrochemical flux be rigorously corrected for to account for the changes in the surface concentration of the reagent? This work presents a simple simulation technique that allows the voltammetry of a disc to be “mass‐transport”‐corrected without recourse to the use of analytical approximations.

Electrolytic characteristics of ammonia oxidation in real aquaculture water using nano-textured mono-and bimetal oxide catalysts supported on graphite electrodes

Electrodes were made by electrochemically deposition of mono-metal (Sn, Mn, Pb, and Co) and bimetal (Co-Zn and Co-Ni) oxides on graphite support using metal tartrate precursor in alkaline solution (pH 12). Results of XRD, XPS, and SEM analyses indicated that the nano-textured oxides were consisted of mineral phases, namely, cassiterite (SnO2), birnessite (δ-MnO2), and plattnerite (β-PbO2), and spinel-type cobalt oxides (Co3O4, ZnCo2O4, and NiCo2O4). Cobalt oxide electrode exhibited high chlorine yield because of improved electrical capacitance and transfer coefficient. The rate of chlorine evolution on CoO/G, CoZnO/G, and CoNiO/G electrodes was >2 × 10−4 min−1, which was almost one order magnitude greater than that of other mono-metal oxides (3–8 × 10−5 min−1). The removal of ammonia nitrogen was > 90% under breakpoint chlorination for the treatment of real aquaculture wastewater ([NH4+] ≈ 3 mg-N/L or 2.1 × 10−4 M, [Cl−] = 0.37 M, current density = 3.5 mA/cm2).

Electrochemical detection of natural organic matter (humic acid) and splitting of hydrogen peroxide on a micropore 3D catalytic polysulfone–copper oxide nanocomposite surface

The development of new metalloplastic material from the combination of an alkaline-fused dehydrated glucose–copper (II) chloride, carbon soot, and polysulfone and the evaluation of its potential for the electrochemical detection of a pro-carcinogenic humic acid in water is reported. Excellent detection limit greater than 1 pico-part-per-million (order of 10–13 mg/L) was achieved, a value that proved to be first-of-its-kind till date. Transfer coefficients between 0.8 and 1.0 were realized. The new material showed some potential for splitting hydrogen peroxide to oxygen and thus may be explored for energy application in addition to its use as a water quality monitoring probe.

Effects of Various Operating Parameters on the Performance of an Air Breathing PEM Fuel Cell

The objective of the presented work is to study the operating parameters and their effects on the performance of an air breathing PEM fuel cell. In this study, we have theoretically calculated the losses associated with the fuel cells. The performance of the fuel cell can be determined by using the polarisation curve. Polarization curves from which the output voltage can be found are studied in detail. The drop in cell voltage occurs due to several irreversibility in the working environment. Reduction in resistance due to activation energy, mass transport and charge transport can help in increasing the performance of the Fuel cells. The performance of a fuel cell is also affected by the factors such as exchange current density, transfer coefficient. The operating parameters like pressure, temperature are varied and the performance of the PEM fuels cells is recorded.

Assessment of different multipurpose tree species for phytoextraction of lead from lead-contaminated soils

Phytoextraction of heavy metals by trees is less hazardous for human beings and animals than their extraction by agricultural crops from the contaminated sites. Therefore, phytoextraction potential of four tree species namely Eucalyptus tereticornis Sm. (eucalyptus), Leucaena leucocephala Lam. de Wit (subabul), Melia azedarach L. (dhrek), and Dalbergia sissoo Roxb. (shisham) to tolerate and extract lead (Pb) from soil at its six applied rates (0, 30, 60, 120, 180, and 240 mg Pb kg − 1 soil) was assessed after 18 months of their growth in a pot experiment. Dry matter (DM) yield of different tree components (stem, leaves, and roots), their Pb concentration, Pb uptake and available Pb in the soil before planting and after harvesting the plants were determined. Contamination indices namely transfer coefficient (TC) or bioaccumulation factor for shoots (BAFshoot), bioaccumulation factor for roots (BAFroot), translocation factor (TF), tolerance index (TI), and the remediation factor (RF) were also determined. The increasing Pb levels led to a significant decrease in total DM yield and in eucalyptus, subabul, dhrek, and shisham, it decreased by 38.9, 34.6, 23.3, and 23.5% at the highest level of applied Pb as compared to control (P ≤ 0.05). The Pb concentration in different plant parts increased significantly with increasing levels of added Pb (P ≤ 0.05). Subabul had significantly highest (0.25 − 100.9 mg pot − 1) removal of Pb at different applied Pb levels and therefore, subabul pots had the lowest amount of available soil Pb after harvesting of plants. Dhrek was observed to have highest (56.4 mg kg − 1 soil) upper critical level of available soil Pb whereas subabul had the greatest Pb extraction capacity from the soil. Contamination indices TF (1.35) and TI (0.88) were highest for dhrek but TC or BAFshoot (3.23), BAFroot (2.66), and RF (7.65%) were highest for subabul. Therefore, subabul can be used for phytoremediation of Pb-contaminated sites due to its more biomass and higher extraction of Pb from soil than the other tree species.

Alternate wetting and drying irrigation and phosphorus rates affect grain yield and quality and heavy metal accumulation in rice

Alternate wetting and drying (AWD) irrigation was reported to increase rice root activity and element bioavailability, which results in enhanced heavy metal (HM) absorption and this HM ends up in rice grains. HM uptake was also affected by the levels of phosphorus (P) fertilizer application. HMs enter food chain via consumption of rice grains and cause health problems. In this study, we compared the differences in grain yield, grain quality, water use efficiency (WUE), partial factor productivity of applied P (PFPp), HM contents in different tissues and transfer coefficient (TC) of HMs under a combination of treatments involving two irrigation regimes (continuous flooding (CF) and AWD irrigation) and three P fertilizer application levels (0.4 g P2O5/kg soil, HP; 0.2 g P2O5/kg soil, MP; 0 g P2O5/kg soil, LP). Compared to CF, AWD irrigation increased grain yield (without reducing grain quality), decreased irrigation water use and the number of irrigation events needed and improved WUE and PFPp at all three P fertilizer application levels, while the accumulation of HMs in grains increased when more P was applied. This accumulation of HMs in grains thus requires immediate attention to the level of P fertilizer application and its optimization in water-saving AWD irrigation to minimize grain HM content.

Determination of kinematic parameters of falling drops of standard solution of pesticides during spraying, taking into account geometric dimensions variability

Expansion of range of applied pesticides and liquid mineral fertilizers necessitates continuous improvement of spray nozzle design, allowing to create a monodisperse spray and ensure high-quality application of chemical agents at low doses and minimal losses. The issue of studying the process of falling drops with varying geometric dimensions remains sore. Studies of drop movement in air environment make it possible to determine the falling speed and coordinates on the treated surface, to substantiate the design, dimensions, optimal operating modes and parameters of sprayers and devices for protecting the spray cone from direct exposure to wind, which is especially important at the design stage of sprayer for field spraying machines. The paper presents simulation of process of falling drops of pesticide standard solution in resisting environment, considering geometric dimensions variability. An equation for drop radius variability depending on the unit motion horizontal transverse variability, formula for variability of intensity of drop decrease depending on the initial conditions and state of environment are obtained. Dependence between coefficients of drop displacement along the horizontal transverse to the unit movement axis and time is obtained, expressions for variability of drop radius depending on the horizontal displacement and the equation for variability of velocity and vertical coordinate of drop movement on time are presented. The coefficient of mass transfer from the drop surface is determined depending on the resistance coefficient, initial velocity, medium density at the border of drop and plant medium subjected to treatment. The results obtained can be used in mechanical engineering for design and testing of sprayers and nozzles, design of wind protection devices for spray cones of standard solutions of pesticides in field sprayers, in simulation of process of drop movement with varying mass.

Multiscale model for flow and transport in CO2-enhanced coalbed methane recovery incorporating gas mixture adsorption effects

In this work we develop a multiscale model for flow and transport problem in CO2-enhanced coalbed methane recovery. The coalbed methane reservoir is characterized by two levels of porosity associated with nanopores in the matrix and cleat network. Mass conservation equations for fluid mixture (CH4 and CO2) in the matrix at the microscale are rigorously derived by using the formal homogenization technique taking into account the gas mixture adsorption in the nanopores. The Density Functional Theory (DFT) is used to compute the gas adsorption isotherms and the solvation force acting on the nanopore wall, showing a much more pronounced adsorption capacity of CO2 compared to CH4. The average transport equations in the matrix together with the multiphase flow problem in fracture network (gas mixture and water) are homogenized giving rise to a macroscopic model ruled by the effective conductivities, partition and transfer coefficients. The cleat permeability evolution due to deformation is taken into account through a three-scale poromechanical model reported in a previous work. Computational simulations illustrate the macroscopic laws underlying the gas pressure distributions, cleat closure phenomena and CH4 production curve enhanced by CO2 injection.

High-valent ruthenium(IV)-oxo complex stabilized mesoporous carbon (graphitized)/nafion modified electrocatalyst for methanol oxidation reaction in neutral pH

Abstract Owing to its importance in the fuel cell, biofuel and bioinorganic chemistry, since 1981, there has been an immense interest in the development of surface-confined ruthenium-oxo complex and to utilize it as a model bio-mimicking system for oxidation of water and alcohol reactions. In this connection, ruthenium-oxo complex has been attached on solid-surfaces by various chemical approaches. Indeed, the preparation of stable and fouling-free surface-confined ruthenium-complex system is a challenging task. Herein, we report a new methodology based on a modification of [Ru(tpy)(DMSO)Cl2]-Nafion (Nf) precursor, wherein, tpy = 2,2′:6′,2″-terpyridine ligand, system on a graphitized mesoporous carbon (GMC) modified electrode followed by electrochemical treatment for in-situ conversion to a high-valent ruthenium oxo complex electrode, designated as GCE/GMC@[(tpy)RuIV/III=O]-Nf, in pH 7 phosphate buffer solution. It showed a stable and well-defined redox peak at a standard electrode potential, Eo’ = 0.780 V vs Ag/AgCl with a surface-excess value, 5.5 × 10−9 mol.cm−2. Some of the kinetic parameters such as transfer coefficient, α and heterogeneous electron-transfer rate constant, ks values were evaluated as 0.54 and 2.43 s−1 respectively for the redox couple. Collective physicochemical characterizations of the surface-confined system by TEM, Raman, UV–Vis and FTIR spectroscopic techniques and ESI-MS analysis, it has been revealed that [RuIII(tpy)(DMSO)(Cl)(OH)]+ complex is surface-confined on the electrode via π-π interaction, pore-encapsulation, and ionic interaction and further transformed to [(tpy)(DMSO)RuIVO]2+ like complex at an applied bias potential, 0.8 V vs Ag/AgCl. This new surface-confined electrode showed high efficient and enzyme-free electrocatalytic oxidation of methanol with a current sensitivity of 39 μA mM−1 in a neutral pH solution.

Preparation of Dawson heteropolyacid-embedded silver nanoparticles/graphene oxide nanocomposite thin film used to modify pencil graphite electrode as a sensor for trace electrochemical sensing of levodopa.

Measurement of levodopa (LD) as the most efficient treatment accessible for controlling the symptoms of Parkinson's disease was investigated. The electrocatalytic measurement of LD was performed at the surface of pencil graphite electrode (PGE) modified with graphene oxide (GO) and silver nanoparticle@Dawson heteropolyacid (AgNPs@DHPA). For this purpose, GO and the intermediate (AgNPs@DHPA) were first synthesized using a simple, cost-effective and straightforward method. The synthetic compounds, morphology, and surface characteristics of the modified sensor were evaluated. The results demonstrated that AgNPs@DHPA well-dispersed on the GO/PGE surface with a mean size of 6.27nm and thickness of 42nm. The electrochemical behavior of the modified PGE was also investigated. The heterogeneous charge transfer rate constant (ks) and transfer coefficient (α) for the electron transfer between AgNPs@DHPA/GO and PGE were obtained as 16.44s-1 and 0.59, respectively. Also, the diffusion coefficient of LD for AgNPs@DHPA/GO/PGE thin film was calculated using chronoamperometric experiments (D=9.05×10-6cm2s-1). Optimal parameters were obtained to access the best response for the measurement of LD. The results revealed that the modified PGE was able to measure the trace amounts of LD in phosphate buffer solution (pH=6.0) in the concentration ranges from 3.0×10-9 to 1.0×10-7M and 1.0×10-7 to 1.0×10-5M. The calculated limit of detection was obtained 7.6×10-10M which was much better than the previously reported electrochemical sensors. The modified electrode was used to measure LD in tablet, blood serum and urine.

Application of Irreversible Thermodynamics to Diffusion in Solids with Internal Surfaces

AbstractTwo types of additional variables were included in the set of state variables and were used for a thermodynamic description of diffusion in an ordinary thermodynamic system. Vacancies are included in the mass balance. Internal surfaces are massless but are characterized by some energy, which is included in the energy balance of the thermodynamic system. Fluxes of components, vacancies, and surfaces were expressed via two groups of thermodynamic constitutive equations of with cross effects. The first group follows from the Gibbs equation. These are state equations in a differential form. The second group relates generalized thermodynamic fluxes to generalized thermodynamic forces. It was shown for a binary system that only three of six transfer coefficients are independent even if the mass transfer mechanism caused by the stress gradient is taken into account.

Insight into intermolecular interactions and hydration properties of biologically active amino acids in aqueous solutions of cefepime: volumetric, compressibility and viscometric studies

The measurement of density, speed of sound and viscosity of an amino acid and its dipeptide i.e., glycine and glycylglycine in aqueous solution of antibiotic drug cefepime has been carried out at various temperatures. The density and speed of sound data has been used to obtain partial molar volume partial molar expansion coefficient second derivative hydration number (), isentropic compressibility partial molar isentropic compressibility partial molar volume of transfer and partial molar isentropic compressibility of transfer The viscosity data have been used to calculate the viscosity B–coefficients, its temperature derivative dB/dT, viscosity B–coefficient of transfer () and various thermodynamic parameters of activation of viscous flow i.e., and for amino acid/peptide in cefepime solutions. The dependence of these parameters upon concentration and temperature clearly suggests the role of amino acid/peptide and cefepime in solute-solvent interactions. The obtained results have been explained on the basis of competing pattern of interactions between the co-solute and solute in the studied ternary system in order to deduce important information regarding drug-amino acid/peptide interactions.

Verification of Radiative Transfer Schemes for the EHT

The Event Horizon Telescope (EHT) Collaboration has recently produced the first resolved images of the central supermassive black hole in the giant elliptical galaxy M87. Here we report on tests of the consistency and accuracy of the general relativistic radiative transfer codes used within the collaboration to model M87* and Sgr A*. We compare and evaluate (1) deflection angles for equatorial null geodesics in a Kerr spacetime; (2) images calculated from a series of simple, parameterized matter distributions in the Kerr metric using simplified emissivities and absorptivities; (3) for a subset of codes, images calculated from general relativistic magnetohydrodynamics simulations using different realistic synchrotron emissivities and absorptivities; (4) observables for the 2017 configuration of EHT, including visibility amplitudes and closure phases. The error in total flux is of order 1% when the codes are run with production numerical parameters. The dominant source of discrepancies for small distances is the location and detailed setup of the software camera that each code uses to produce synthetic images. We find that when numerical parameters are suitably chosen and the is sufficiently far away the images converge and that for given transfer coefficients, numerical uncertainties are unlikely to limit parameter estimation for the current generation of EHT observations. The purpose of this paper is to describe a verification and comparison of EHT radiative transfer codes. It is not to verify EHT models more generally.

Biochar effect on crop performance and Pb and Zn uptake of tomato (Solanum lycopersicum, L.) plants grown on heavy metals contaminated Kosovo soils

A greenhouse pot experiment was conducted to evaluate the effect of biochar on the growth and uptake of Pb and Zn by tomato plants (Solanum lycopersicum, L.) cultivated in two highly contaminated Kosovo soils, A and B. Plants were cultivated in the biochar amended and unamended soils. As expected, the biochar addition to the two polluted soils has contributed to significantly improve the crop yields, in terms of both fresh and dry weight. Further, results indicated that the effect of biochar on metal mobility is closely related, besides its properties, to soil’s native characteristics. In fact, the addition of biochar to soil B had also beneficial effects on the uptake of both metals, halving in some cases the values of the biological accumulation and transfer coefficients, while it did not show the same efficacy on soil A.

Migration of antioxidants from polylactic acid films, a parameter estimation approach: Part II – assessment of partition, diffusion and convective mass transfer coefficients

Abstract Migration kinetics of a polymer-food system can be studied using physical parameters such as the diffusion (D), partition (Kp,f), and convective mass transfer (h) coefficients. A mathematical model considering all three important migration parameters was proposed in part I of this paper series. However, there are other existing mass transfer models focus solely on either D and/or Kp,f. With various options available, how would a researcher choose an appropriate mathematical model for investigating the kinetics migration of a food packaging-simulant system? To address this question, this paper analyzes and compares the newly proposed mathematical model with the existing ones using a selected migration case study. Based on the output, a decision tree analysis for determining mass transfer parameters for migration studies is proposed. The decision tree analysis was beneficial as guidance and was able to provide an insight into the kinetic behaviors of a migrant in a polymer-food system by providing a method to select the right model for the aforementioned system.

Reduced graphene oxide and carbon nanotubes composite functionalized by azobenzene, characterization and its potential as a curcumin electrochemical sensor

In this study, azobenzene-modified reduced graphene [email protected] carbon nanotubes ([email protected]) was synthesized and characterized by UV–Vis, FT-IR, XRD, FE-SEM, AFM, TEM, EDS, element mapping, BET, and cyclic voltammetry (CV). A glassy carbon electrode (GCE) was modified with [email protected] as an electrochemical sensor for determination of curcumin. Electrochemical impedance spectroscopy (EIS) and CV were used to study the efficiency of the catalyst. Subsequently, various effective parameters on the sensitivity and selectivity of the method, including pH, accumulation potential, and preconcentration time, were optimized. The transfer coefficient, as well as the electron transfer rate constant, were respectively calculated using the Laviron equation as 0.55 and 0.32 s−1. The linear ranges of the sensor were 0.008–2.0 and 2.0–10.0 μmol L−1 curcumin with a limit of detection of 0.003 μmol L−1 using square wave voltammetry (SWV). The repeatability and reproducibility were 2.0% (RSD) and 3.6% (RSD), respectively. The selectivity of the method for determination of curcumin in the presence of different interference species was studied too. Finally, the proposed sensor for determining curcumin was tested with real samples, including plasma, urine, and pharmaceutical compounds.

UTILIZATION OF SODIUM SULFIT DROPLET FOR OXYGEN ABSORPTION

Gas absorption by liquid droplets in a spray column is one common method for gas cleaning. The simple design, low pressure drop, and the possibility of its application in liquid systems containing solids are benefi ts of this method. The mass transfer coeffi cient of gas-liquid absorption depends on droplet size, concentration of liquid or gas and the physic-chemical system. Experiments to study the mass transfer using the air-oxygen/sulphite system have been performed. The dispersed droplets were generated by pumping the liquid through a needle with certain fl owrate. A High Speed Camera with shadowgraph method and image processing was used for measurement of droplet size and velocity accurately. The shapes of the droplets were relatively not spherical because of oscillating movement. The droplets are slightly accelerated after detach from the needle. The oxygen concentrations were determined by means of spectrophotometric method. The liquid mass transfer coeffi cients of this experiment are 2 times lower than the model because of the low reaction between oxygen and sulphite . The mass transfer coeffi cient of the experiment is calculated from the experimental data, and compared with the model equations from the literature.

Acoustic-to-seismic ground coupling: coupling efficiency and inferring near-surface properties

SUMMARYA fraction of the acoustic wave energy (from the atmosphere) may couple into the ground, and it can thus be recorded as ground motion using seismometers. We have investigated this coupling, with two questions in mind, (i) how strong it is for small explosive sources and offsets up to a few tens of meters and (ii) what we can learn about the shallow subsurface from this coupling. 25 firecracker explosions and five rocket explosions were analysed using colocated seismic and infrasound sensors; we find that around 2 per cent of the acoustic energy is admitted into the ground (converted to seismic energy). Transfer coefficients are in the range of 2.85–4.06 nm Pa–1 for displacement, 1.99–2.74 μm s–1 Pa–1 for velocity, and 2.2–2.86 mm s−2 Pa–1 for acceleration. Recording dynamic air pressure together with ground motion at the same site allows identification of different waves propagating in the shallow underground, notably the seismic expression of the direct airwave, and the later air-coupled Rayleigh wave. We can reliably infer shallow ground properties from the direct airwave, in particular the two Lamé constants (λ and μ) and the Poisson ratio. Firecrackers as pressure sources allow constraining elastic parameters in the top-most layer. In this study, they provide frequency-dependent values of λ decreasing from 119 MPa for low frequencies (48 Hz) to 4.2 MPa for high frequencies (341 Hz), and μ values decreasing from 33 to 1.8 MPa. Frequency-dependent Poisson ratios ν are in the range of 0.336–0.366.

Supercritical Extraction of Heracleum persicum Plant and Mathematical Modeling

Background: Supercritical CO2 is the most applicable solvent because of its unique properties such as; high selectivity, non-explosivity, non toxicity, low cost of purchasing and its unique critical points. The solubility of this solvent changed rapidly with only a small change in pressure and temperature especially in pressure. According to literatures, the method of supercritical extraction is the best technology for extracting sensitive constituents. Despite of numerous studies in the literature for extracting essential oil from plants, no studies can be found about this valuable medicinal plant by CO2 supercritical extraction method. Method: In this study, the extraction of main medicinal constituents from Heracleum Persicum and mathematical modeling was done using supercritical carbon dioxide. The experimental data were investigated was analyzed by using gas chromatography (GC) and mass spectrometer chromatography (GC-MS) methods. The model of seed and bed, which includes three parameters of mass transfer, axial dispersion, and effective penetration coefficients, were used for modeling the extraction process. This model was used based on the equilibrium of the fluid phase and solid phase to communicate with the experimental data. Then the obtained yield of supercritical technology was compared with the hydro distillation method. Results: The main extracted constituents of some different varieties of Heracleum by different methods and solvents have been determined. The extracted chemicals by supercritical fluid technology from the seeds of the Heracleum Persicum encompasses hexyl butanoate, octyl 2- methyl butyrate, octylisobutyrate and anethole which are so effective against epilepsy and has the most antibacterial, antiviral and antifungal effects. So supercritical fluid extraction is more selective than the other methods. Conclusion: Extracting of essential oil and mathematical modeling from H. persicum were performed under different operating conditions of temperature, pressure, particle size and solvent flow rate. Experimental and modeling results showed that the operating parameters used in different conditions had a different effect on extraction efficiency and model parameters.

Using electromagnetic induction technology to identify atrazine leaching potential at field scale

Atrazine is an herbicide commonly used to control weeds in corn crop. Atrazine becomes an environmental concern when it moves off-site to surface and ground waters. Understanding how atrazine moves in the field is important for developing management controls. Electromagnetic induction (EMI) has been used to map certain contaminant transport at the field scale. This study was developed to evaluate the efficacy of EMI technology for identifying surface soil atrazine concentration in a corn crop field. The research was conducted in a corn silage field with silt, clay and loam soils at the U.S. Meat Animal Research Center (USMARC), Clay Center, NE – USA, and it was divided in three stages; i) EMI data collection and a response surface sampling design for collection of bulk soils and soil core samples, ii) atrazine transport parameters were obtained by Breakthrough Curves using the bulk soil and numerical adjustments using STANMOD (HYDRUS package), and iii) Modeling atrazine parameters through EMI signal data with posterior atrazine’s movement simulations through the soil using HYDRUS 2D. Atrazine’s retardation factor, partition coefficient, and transfer coefficient were strongly correlated with EMI signal exhibiting a strong correlation with apparent electrical conductivity (ECa). The low values for RMSE and RRMSE and the high values for Willmott and Pearson coefficients indicate EMI technology can be used to predict atrazine movement parameters. HYDRUS 2D quantitatively simulates the atrazine concentration leaching and how the temporal scale of this contamination would be. Combining EMI technology with HYDRUS 2D modeling provides researcher with additional information for developing better management practices for controlling atrazine movement to surface water; however, further studies are needed determine the effectiveness of this approach for other soil types.