A mathematical model is developed to arrive at an optimal conjunctive use policy for irrigation of multiple crops in a reservoir-canal-aquifer system. The integration of the reservoir operation for canal release, ground water pumping and crop water allocations during different periods of crop season (intraseasonal periods) is achieved through the objective of maximizing the sum of relative yields of crops over a year considering three sets of constraints: mass balance at the reservoir, soil moisture balance for individual crops, and governing equations for ground water flow. The conjunctive use model is formulated with these constraints linked together by appropriate additional constraints as a deterministic linear programming model. A two-dimensional isotropic, homogeneous unconfined aquifer is considered for modeling. The aquifer response is modeled through the use of a finite element ground water model. A conjunctive use policy is defined by specifying the ratio of the annual allocation of surface water to that of ground water pumping at the crop level for the entire irrigated area. A conjunctive use policy is termed stable when the policy results in a negligible change in the ground water storage over a normal year. The applicability of the model is demonstrated through a case study of an existing reservoir command area in Chitradurga district, Karnataka State, India.

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Excess molar volumes (V E) and the speed of sound (u) of binary mixtures of N-methyl-2-pyrrolidone with chloroethanes and ethenes have been measured at 303.15 K. The chloroethanes are 1,2-dichloroethane, 1,1,1-trichloroethane, and 1,1,2,2-tetrachloroethane. The chloroethenes are trichloroethene and tetrachloroethene. The speed of sound data were used to compute isentropic compressibilities (κs) and excess isentropic compressibilities (κs E). V E values are negative over the entire mole fraction range. The κs values are negative over the whole volume fraction range for the systems of N-methyl-2-pyrrolidone with 1,1,1-trichloroethane, 1,1,2,2-tetrachloroethane, and tetrachloroethene and positive for the systems of N-methyl-2-pyrrolidone with 1,2-dichloroethane and trichloroethene.

Excess molar volumes (V E ) and speeds of sound (u) of the binary liquid mixtures of N,N-dimethylacetamide (DMA) with chloroethanes and chloroethenes at 303.15 K have been measured over the entire range of compositions. The chloroethanes are 1,2-dichloroethane, 1,1,1-trichloroethane, and 1,1,2,2-tetrachloroethane, and the chloroethenes are trichloroethene and tetrachloroethene. The V E values are positive in mixtures of N,N-dimethylacetamide with 1,2-dichloroethane and tetrachloroethene. The V E values are negative over the whole mole fraction range for N,N-dimethylacetamide with 1,1,1-trichloroethane, 1,1,2,2tetrachloroethane, and trichloroethene. The speed of sound data were used to compute isentropic compressibilities (κ s ) and excess isentropic compressibilities (κ s E ). The κ s E values are positive for the system N,N-dimethylacetamide with 1,2-dichloroethane. For the remaining systems, the κ s E values are negative over the entire range of compositions.

Solid-liquid equilibria of 11 binary mixtures of n-alkanes (octadecane, nonadecane, eicosane, heneicosane, docosane, tricosane, tetracosane, pentacosane, hexacosane, heptacosane, and octacosane) in N,Ndimethylformamide (DMF) have been measured from 275 K to the melting temperatures of the n-alkane. The solubility results have been correlated by the Redlich-Kister (two and three parameters) equation and the NRTL equation.