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Articles 1381 - 1410 of 2083

Full-Text Articles in Civil and Environmental Engineering

Bioengineering For Water Cleanup: State-Of-The-Art Assessment, Judith L. Sims, Ronald C. Sims, Jon S. Ginn Jan 1992

Bioengineering For Water Cleanup: State-Of-The-Art Assessment, Judith L. Sims, Ronald C. Sims, Jon S. Ginn

Reports

No abstract provided.

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A Spatially Distributed Water Balance Based On Physical, Isotropic And Airborne Remotely Sensed Data, C. M.U. Neale, David G. Tarboton, J. J. Mcdonnell Jan 1992

A Spatially Distributed Water Balance Based On Physical, Isotropic And Airborne Remotely Sensed Data, C. M.U. Neale, David G. Tarboton, J. J. Mcdonnell

Reports

Introduction: The objective of this research to develop a spatially distributed water balance model based on the integration of spatially distributed data. Progress this year has consisted of model development, instrument acquisition, installation and development of experimental procedures, and baseline data collection. The original research plan called for detailed observations related to the water balance over the year September 1991 to August 1992. The detailed measurements were to start with accumulation of the snowpack followed by melt and evapotranspiration measurements from March to August. The objective was to measure the energy balance parameters starting with the peak accumulation, through the …

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Nonparametric Stratigraphic Interpretation From Drill Log Data, Upmanu Lall, A. I. Ali Jan 1992

Nonparametric Stratigraphic Interpretation From Drill Log Data, Upmanu Lall, A. I. Ali

Reports

Near surface groundwater contamination is a widespread problem. The potential for contamination of deep aquifers in such areas depends on the vertical hydraulic gradient as well as the extent and location of interconnection between the upper and lower aquifers. In alluvial, sedimentary environment, the geologic units are typically weakly connected lenses or layers of high or low conductivity with variable size, geometry and orientation. Drill logs provide qualitative, local information on such aquifer heterogeneities. A binary (high or low conductivity) indicator function is used to describe the aquifer system. A nonparametric statistical methodology for assessing the probability that a particular …

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Composting Of Explosives Contaminated Soil Using The White Rot Fungus Phanerochaete Chrysosporium, Michael J. Mcfarland, Shashi Kalaskar, Eric Baiden Jan 1992

Composting Of Explosives Contaminated Soil Using The White Rot Fungus Phanerochaete Chrysosporium, Michael J. Mcfarland, Shashi Kalaskar, Eric Baiden

Reports

Bioaugmentation using the white rot fungus Phanerochaete chrysosporium was found to be effective in enhancing TNT removal in lightly (i.e., below 100 mg/kg) contaminated soil. The percent reduction in TNT increased from 15% to 53% when soils were treated with fungal inoculated organic material. Maximum removal rates improved from 0.33 mg TNT/kg-day to 0.76 mg TNT/kg-day during the same treatment. Neither fungal inoculation nor organic amendment addition resulted in improving TNT removal kinetics in highly contaminated soils (i.e., above 1000 mg/kg). Executive Summary: Laboratory scale compost studies were conducted to evaluate the effect of bioaugmentation with the white rot fungus,

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Maximizing Sustainable Ground-Water Withdrawals: Comparing Accuracy And Computational Requirements For Steady-State And Transient Digital Modeling Approaches, Richard C. Peralta, R. R.A. Cantiller, Gary L. Mahon Jan 1992

Maximizing Sustainable Ground-Water Withdrawals: Comparing Accuracy And Computational Requirements For Steady-State And Transient Digital Modeling Approaches, Richard C. Peralta, R. R.A. Cantiller, Gary L. Mahon

Civil and Environmental Engineering Faculty Publications

Rigorous models for maximizing sustainable groundwater withdrawals may require more computer memory for their constraint set than is available. In some situations, alternative constraint formulations yield similar or identical answers resulting in great saving in computer memory requirements. In order to evaluate the efficiency of using alternative constraints1 maximum ground-water withdrawal pumping strategies were computed by three digital models for a hypothetical area for a five-decade period. Model A maximized steady ground-water withdrawal. Model B maximized unsteady ground-water mining. Model C maximized unsteady ground-water mining subject to a constraint that final pumping be sustainable after the end of the 50-year …

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Optimal Linear/Nonlinear, Quantity/Quality Management Of Complex Multilayer Aquifers By Embedding, Ali Gharbi, Richard C. Peralta Jan 1992

Optimal Linear/Nonlinear, Quantity/Quality Management Of Complex Multilayer Aquifers By Embedding, Ali Gharbi, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

The embedding optimization modelling approach is adapted to aid long-term groundwater quality and quantity management of complex nonlinear multilayer aquifers. Implicit block-centered finite-difference approximations of the quasi-three-dimensional unsteady flow equation, and Galerkin finite-element approximations of the twodimensional advection-dispersion transport equation are embedded as constraints in the model. Other hydrological processes are also included as constraints. Cyclical linear differencing permits representation of nonlinear transport, even when contaminant is extracted by unsteady pumping (a decision variable). Also used are nonlinear (discontinuous derivative) constraints describing drainage, stream-aquifer interflow and evapotranspiration. The use of both linear and nonlinear formulations of the entire flow and …

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Fate And Transport Of Tce-Petroleum Hydrocarbon Mixture At Uttr, G. Nash Quashiga, Richard C. Peralta Jan 1992

Fate And Transport Of Tce-Petroleum Hydrocarbon Mixture At Uttr, G. Nash Quashiga, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

In 1988 a preliminary assessment (PA) study was conducted at Chemical Disposal Pit No. 4 to address several concerns of Hill Air Force Base (HAFB), the facility operators. The objectives of the PA were; i) to assess the potential for organic chemical releases to the subsurface environment, and ii) to determine the need for any immediate control measures, if the subsurface environment were threatened.

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Optimizing Perennial Groundwater Yield Planning For Nonlinear Systems: Approach Comparison, Shu Takahashi, Richard C. Peralta Jan 1992

Optimizing Perennial Groundwater Yield Planning For Nonlinear Systems: Approach Comparison, Shu Takahashi, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Four alternative simulation/optimization models useful for computing optimal sustained-yield (steady-state) groundwater pumping strategies are compared in terms of formulation, solution procedure, accuracy, and computational efficiency. The different models require different computer processing time and memory. For the aquifer tested system, if more than 10% of the cells have pumping as a decision variable, a fully linearized embedding model will require less computer memory than any other model. All the models address linear and nonlinear steady-state flow in multilayer, unconfined/confined aquifers. They also address several types of nonsmooth external flows. Newly presented are a response matrix model solving external flows described …

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Optimizing Ground Water Planning And Management, Richard C. Peralta, L. S. Willardson Jan 1992

Optimizing Ground Water Planning And Management, Richard C. Peralta, L. S. Willardson

Civil and Environmental Engineering Faculty Publications

Simulation/optimization (S/0) models can be used to speed the process of computing long term groundwater pumping strategies. These combined models can also greatly ease the planning tasks of water management agencies. They make the process of computing optimal perennial yield groundwater management strategies fairly straightforward. S/0 models dramatically improve conjunctive water management and can help minimize the cost of groundwater contaminant clean-up. The differences between S/0 models and the simulation (S) models currently used by over 98 % of practitioners are illustrated with recent applications of S/0 models in regional planning.

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Best Management Practices (Bmps) To Minimize Nitrate Leaching From Irrigated Potatoes, Ahmad Yar Ranjha, Richard C. Peralta, Robert W. Hill Jan 1992

Best Management Practices (Bmps) To Minimize Nitrate Leaching From Irrigated Potatoes, Ahmad Yar Ranjha, Richard C. Peralta, Robert W. Hill

Civil and Environmental Engineering Faculty Publications

Numerous preliminary simulations are again performed to determine the smallest fertilizer amount, applied througii sprinkler irrigations (chemigation), that should still yield 15.3 tons of potatoes per acre. Applying only 68 lbs/ac of ammonium nitrate fertilizer in the first irrigation on June 28, should be sufficient. Again, total crop N uptake equals potential crop N uptake throughout the growing season. Except for the net income and applied fertilizer N uptake efficiency, all the other results computed by NLEAP (Figure 4 and Table 1) are very similar to results of scenario II. Applied fertilizer N uptake efficiency is the highest (91%) in …

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Optimal Groundwater Quantity/Quality Planning For Salt Lake Valley, Ali Gharbi, Richard C. Peralta Jan 1992

Optimal Groundwater Quantity/Quality Planning For Salt Lake Valley, Ali Gharbi, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Generally, the embedding technique for optimizing groundwater management has been limited to small scale or steady-state groundwater flow management cases. The embedding approach causes sparse, highly structured constraint matrices which have been sometimes difficult to solve. Embedding applications have been limited by lack of: optimization algorithms able to easily address such matrices for large scale problems, and efficient methods for addressing common nonlinearities and converging to a solution. Computer software, USUEM, addresses these issues by: creation of alternative linear, nonlinear, combined and partitioned formulations of the same problem, implemention of an efficient cycling procedure, and good selection of optimization algorithm …

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Pluman, Decision Support System For Groundwater Contaminant Plume Simulation/Optimization Management Model, Herminio H. Suguino, Richard C. Peralta Jan 1992

Pluman, Decision Support System For Groundwater Contaminant Plume Simulation/Optimization Management Model, Herminio H. Suguino, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

No abstract provided.

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Optimal Management Of Irrigation And Vadose Zone Pesticide Transport, M. A. Hegazy, Richard C. Peralta Jan 1992

Optimal Management Of Irrigation And Vadose Zone Pesticide Transport, M. A. Hegazy, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

A management model is developed for maximizing crop yield while avoiding unacceptable pesticide leaching. Utilized constraint equations: maintain a soil moisture volume balance, describe downward pesticide transport, and limit the amount of pesticide reaching groundwater. The reported optimization model is the first which includes unsaturated zone pesticide transport. It is designed to help prevent nonpoint-source contamination of shallow groundwater aquifers. The model computes optimal irrigation amounts for given soil, crop, chemical, and climate data and irrigation frequencies. The model is tested for different irrigation scenarios. The modeling approach is promising as a tool to aid developing environmentally sound agricultural production …

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Optimal Perennial Groundwater Yield Planning For The East Shore Area, Utah, Shu Takahashi, Richard C. Peralta Jan 1992

Optimal Perennial Groundwater Yield Planning For The East Shore Area, Utah, Shu Takahashi, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Computer models are developed for computing optimal perennial groundwater withdrawal strategies for the East Shore Area of Utah's Great Salt Lake. The underlying aquifer has three confined or unconfined layers. Both embedding and response matrix (RM) approaches are tested and compared. Historically, it has been difficult to incorporate simulation of an unconfined aquifer and many external flow equations described by nonsmooth functions within linear programming models. RM models normally assume system linearity. The presented RM model overcomes this difficulty using cycling and influence coefficients generated with a modified MODFLOW model. In this groundwater flow simulation model, the above nonlinear terms …

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Comparing Simulated And Experimental Hysteretic Two-Phase Transient Fluid Flow Phenomena, R. J. Lenhard, J. C. Parker, Jagath J. Kaluarachchi Aug 1991

Comparing Simulated And Experimental Hysteretic Two-Phase Transient Fluid Flow Phenomena, R. J. Lenhard, J. C. Parker, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

A hysteretic model for two-phase permeability (k)-saturation (S)-pressure (P) relations is outlined that accounts for effects of nonwetting fluid entrapment. The model can be employed in unsaturated fluid flow computer codes to predict temporal and spatial fluid distributions. Consideration is given to hysteresis in S-P relations caused by contact angle, irregular pore geometry, and nonwetting fluid entrapment effects and to hysteresis in k-Srelations caused by nonwetting fluid entrapment effects. An air-water flow experiment is conducted with a 72-cm vertical soil column where the water table is fluctuated to generate scanning S-P paths. Water contents are measured via a gamma radiation …

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Optimal Aquifer Planning With Salt Water Boundary, Richard C. Peralta, Shu Takahashi Jul 1991

Optimal Aquifer Planning With Salt Water Boundary, Richard C. Peralta, Shu Takahashi

Civil and Environmental Engineering Faculty Publications

Optimal sustained-yield pumping strategies were developed for the irrigated and industrialized eastern shore of the Great Salt Lake. The combined optimization and simulation model, in which steady-state, finite difference, quasi-three-dimensional ground water flow equations were embedded as constraints, computes the optima,! distribution for sustainable annual ground water pumping rates for alternative scenarios. 1. The model deals with management of a large, multilayer, confined/unconfined (linear/nonlinear) aquifer system. 2. The research can help manage water in the study area where· the demand for water of sufficient quality and quantity is increasing due to urbanization.

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Optimal Sustained-Yield Groundwater Pumping Strategy For The East Shore Area, Utah, Shu Takahashi, Richard C. Peralta Jun 1991

Optimal Sustained-Yield Groundwater Pumping Strategy For The East Shore Area, Utah, Shu Takahashi, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Optimal sustained-yield pumping strategies were developed for the irrigated and industrialized eastern shore of the Great Salt Lake. The combined optimization and simulation model contains steady-state, finite difference, quasi-three-dimensional, groundwater flow equations embedded as constraints. The model computes the optimal spatial distribution of sustainable annual groundwater pumping rates for alternative scenarios. The addressed aquifer is a multilayer and confined/unconfined (linear/nonlinear) system. The research can help manage water in the study area, where the demand for water of sufficient quality and quantity is increasing due to urbanization.

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Effects Of Alternative Sprinkler Irrigation Parameters On Pesticide Movement, Ahmad Yar Ranjha, Richard C. Peralta, Robert W. Hill, Antonio Maria Requena, Howard M. Deer, Majid Ehteshami May 1991

Effects Of Alternative Sprinkler Irrigation Parameters On Pesticide Movement, Ahmad Yar Ranjha, Richard C. Peralta, Robert W. Hill, Antonio Maria Requena, Howard M. Deer, Majid Ehteshami

Civil and Environmental Engineering Faculty Publications

The relative reduction in potential ground-water contamination due to pesticides at several sites in Utah was determined by comparing alternative irrigation system designs, water management practices and pesticides. Alternative sprinkler irrigation distribution coefficients were used to estimate infiltration depths. The movement of pesticides through soils following sprinkler irrigations was simulated with one-dimensional model. Pesticide contamination of ground water can be reduced by careful selection of pesticides, properly designed irrigation systems and improved water management techniques. Procedures for selecting an appropriate sprinkler design and pesticide are presented.

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Calibration Of A Parametric-Stochastic Model, Zhida Song, L. Douglas James Jan 1991

Calibration Of A Parametric-Stochastic Model, Zhida Song, L. Douglas James

Reports

Conceptually, stochastic parametric modeling offers a powerful tool to select a scale for expressing catchment variability for hydrologic simulation and relating model parameters to catchment characteristics. Practically, success depends on having an efficient method for model calibration. The calibration of a stochastic model is much more difficult than a deterministic one because simulation shifts from using fixed parameters to simulate of flows as deterministic values to taking multiple combinations of paramter values randomly from distributions to simulate flows as stochastic variables. The proposed method calibrates the first two moments of each parameter distribution to represent the average and the variability …

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Studies Related To Nutrients Entering Groundwater From The Heber Valley Sewer Farm And Dairies, Roland W. Jeppson, Joan Mclean, Calvin G. Clyde, Scott Korom Jan 1991

Studies Related To Nutrients Entering Groundwater From The Heber Valley Sewer Farm And Dairies, Roland W. Jeppson, Joan Mclean, Calvin G. Clyde, Scott Korom

Reports

Foreword: This report includes the results from a two year study in the Heber Valley to determine amounts of nutrients that are entering the groundwaters of the Heber Valley, and might ultimately enter Deer Creek Reservoir. Since Deer Creek Reservoir in Heber Valley, Utah supplies approximately 65 percent of the water distributed to Salt Lake County, the maintenance of its quality is of considerable importance. To maintain the quality of this reservoir and limit its eutrophication "best management" practices for surface water have been implemented gradually during the past decade in Heber Valley. These practices have significantly improved the qualities …

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Sectar: Model For Economically Optimal Sustained Groundwater Yield Planning, Richard C. Peralta, K. Asghari, R. N. Shulstad Jan 1991

Sectar: Model For Economically Optimal Sustained Groundwater Yield Planning, Richard C. Peralta, K. Asghari, R. N. Shulstad

Civil and Environmental Engineering Faculty Publications

This paper presents an approach for computing economically optimal sustained yield ground-water extract ion strategies and supportable irrigated crop acreages. Computed regional strategies maximize the present value of net economic return_ They are useful for long-term agricultural planning because they are sustainable even beyond the planning period considered within the economic optimization. The hybrid approach uses only steady-state flow equations and iterative simulation/optimization to reduce optimization memory requirements below that required by conventional models utilizing both steady and unsteady equations. SECTAR, a quadratic optimization planning model assumes heads will evolve toward optimal steady-state but does initially not know the nonlinear …

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Assessing Pesticide Contamination To Groundwater: A Rapid Approach, Majid Ehteshami, Richard C. Peralta, Hubert Eisele, Howard M. Deer, Terry Tindall Jan 1991

Assessing Pesticide Contamination To Groundwater: A Rapid Approach, Majid Ehteshami, Richard C. Peralta, Hubert Eisele, Howard M. Deer, Terry Tindall

Civil and Environmental Engineering Faculty Publications

A methodology has been developed for identifying hazardous pesticides/site combinations threatening ground-water contamination. Screening methodologies are required to determine which locations and pesticides now in use should receive the greatest attention to safeguard the public health. The presented method uses a hazard to ground-water hydrogeological screening model (DRASTIC) and employs a one-dimensional pesticide transport model ( CMLS). The method is an efficient and practical technique to identify where particular combinations of pesticides, water management practices, soils, and geology result in the greatest potential hazard to ground-water contamination. Use of the presented approach can reduce sampling needs and expense.

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Comment On "On The Fractal Dimension Of Stream Networks" By Paolo La Barbera And Renzo Rosso, David G. Tarboton, Rafael L. Bras, Ignacio Rodriguez-Iturbe Sep 1990

Comment On "On The Fractal Dimension Of Stream Networks" By Paolo La Barbera And Renzo Rosso, David G. Tarboton, Rafael L. Bras, Ignacio Rodriguez-Iturbe

Civil and Environmental Engineering Faculty Publications

No abstract provided.

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Pesticide Use On Utah's Crops, Howard M. Deer, Richard C. Peralta, Majid Ehteshami Sep 1990

Pesticide Use On Utah's Crops, Howard M. Deer, Richard C. Peralta, Majid Ehteshami

Civil and Environmental Engineering Faculty Publications

Utah State University's Cooperative Extension Service has placed high priority on a Water Quality Initiative for Utah. As a part of that emphasis, a research project was initiated to analyze the hazards that agricultural chemicals pose to Utah's ground water. The initial phase of this research was to determine those locations in Utah that are at greatest risk of ground water contamination by pesticides. This was accomplished by interfacing data on pesticide usage with soil and hydrologic factors. The results identified specific areas in the state where potential hazards exist. This report summarizes data on the use of pesticides on …

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Research Project Summaries (July 1989-December 1990), Utah Water Research Laboratory Jul 1990

Research Project Summaries (July 1989-December 1990), Utah Water Research Laboratory

Reports

From every side we hear of new threats to our water supply. Carcinogens, droughts, dam failures, global warming, hazardous wastes, deforestation, overpopulation, liability, and an aging infrastructure become household fears; this list grows longer and more foreboding to the average citizen. Some of these threats are real, while others are imaginary. Some we know how to overcome and others we can find ways to overcome, yet, for some, we are still helpless. The strength of a university lies in its success in stimulating inquisitive minds in critical examination of the problems of the world. People sense hope as experts find …

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Use Of Simplex Algorithm For Optimizing Simulation Models, M. Ehteshami, L. S. Willardson, Richard C. Peralta Jun 1990

Use Of Simplex Algorithm For Optimizing Simulation Models, M. Ehteshami, L. S. Willardson, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

A methodology and computer model is developed to determine economically optimum closed subsurface drainage systems in irrigated areas. The mode 1 maximizes net benefits, by comparing profit driven by crop yields to drain system cost and selects an optimum drain layout. The optimization methodology used is the SIMPLEX method (Nelder and Mead, 1965). The SIMPLEX model was linked to the subsurface drainage model DRAINMOD (Skaggs, 1982) and to the surface hydraulic model KINE (Walker and Skogerboe 1987). The selected optimum drainage system maximizes the difference between total revenue, and the total cost of installation, operation and management of a particular …

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Modelling For Potentiometric Surface Management Of Multilayer Aquifer Systems, A. Gharbi, Richard C. Peralta, K. M. Waddell Jun 1990

Modelling For Potentiometric Surface Management Of Multilayer Aquifer Systems, A. Gharbi, Richard C. Peralta, K. M. Waddell

Civil and Environmental Engineering Faculty Publications

Assuring the long-term availability of groundwater of adequate quality and quantity frequently requires the implementation of appropriate ground-water and conjunctive water management strategies. Presented is a model for developing optimal strategies for an multilayer aquifer in which stream-aquifer interflow is affected by the potentiometric surface and ground-water use. The model is applied to the Salt Lake Valley. Discussed is the use of pumping to control: l) potential migration of non-point source agricultural contaminants between aquifer layers and 2) the movement of a mile-long plume caused by mining waste.

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Effects Of Alternative Furrow Irrigation Parameters On Pesticide Movement In Cropped Areas In Utah, Antonio Maria Requena, Ahmad Yar Ranjha, Richard C. Peralta, Howard M. Deer, Majid Ehteshami, Robert W. Hill Jun 1990

Effects Of Alternative Furrow Irrigation Parameters On Pesticide Movement In Cropped Areas In Utah, Antonio Maria Requena, Ahmad Yar Ranjha, Richard C. Peralta, Howard M. Deer, Majid Ehteshami, Robert W. Hill

Civil and Environmental Engineering Faculty Publications

Production of adequate supplies of food and fiber currently requires that pesticides be used to limit crop losses caused by insects, pathogens, weeds and other pests. Although pesticides are necessary in today' s agriculture, they can be a serious problem if they reach and contaminate ground water, especially where drinking water needs are met by ground water. The relative reduction of potential ground-water contamination due to agricultural use of pesticides was analyzed for particular sites in Utah. The potential reduction of pesticides in ground water was considered by utilizing alternative irrigation systems, water management practices and pesticides. A one-dimensional simulation …

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Pesticide And Water Management Alternatives To Mitigate Potential Ground-Water Contamination For Selected Counties In Utah, Majid Ehteshami, Antonio M. Requena, Richard C. Peralta, Howard M. Deer, Robert W. Hill, Ahmad Yar Ranjha May 1990

Pesticide And Water Management Alternatives To Mitigate Potential Ground-Water Contamination For Selected Counties In Utah, Majid Ehteshami, Antonio M. Requena, Richard C. Peralta, Howard M. Deer, Robert W. Hill, Ahmad Yar Ranjha

Civil and Environmental Engineering Faculty Publications

Production of adequate supplies of food and fiber currently requires that pesticides be used to limit crop losses from insects, pathogens, weeds and other pests. Although pesticides are necessary in today's agriculture, they can be a serious problem if they reach and contaminate ground water, especially in places where drinking water needs are supplied from ground water. The relative reduction of potential ground-water contamination due to agricultural use of pesticides was analyzed for particular sites in Utah. The potential reduction of pesticides in ground water was considered by utilizing alternative irrigation systems, water management practices and pesticides. A one-dimensional simulation …

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Modeling Of Multicomponent Organic Chemicaltransport In Three Phase Porous Media, Jagath J. Kaluarachchi, J. C. Parker May 1990

Modeling Of Multicomponent Organic Chemicaltransport In Three Phase Porous Media, Jagath J. Kaluarachchi, J. C. Parker

Civil and Environmental Engineering Faculty Publications

A two-dimensional finite-element model was developed to predict coupled transient flow and multicomponent transport of organic chemicals which can partition between nonaqueous phase liquid, water, gas and solid phases in porous media under the assumption of local chemical equilibrium. Gas-phase pressure gradients are assumed negligible and liquid flow equations are solved simultaneously using an upstream weighted solution method with time-lagged interphase mass-transfer terms and phase densities. Phase-summed component transport equations are solved serially after computation of the velocity field also by an upstream weighted finite-element method. Mass-transfer rates are evaluated from individual phase transport equations by back-substitution and corrected for …

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