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The objective of this study was to compare milk protein, amino acid and fatty acid content and composition among two breeds of river buffalo (Murrah and Nili-Ravi), and their hybrid F1 and F2 (crossbreeding with local swamp buffalo). The protein and fat content in milk from crossbreed F1 and F2 were significant higher than that of river buffalo, but the milk yield was still lower than Nili-Ravi and Murrah. The protein composition in crossbreed milk was similar to Nili-Ravi, except κ-casein. Most of amino acid profile of crossbreed milk was similar with river water buffalo, however, significant difference was found in three essential amino acids (Met, Leu and Phe) and four nonessential amino acids (Ser, Glu, Ala and Cys). The fatty acid profile of crossbreed milk was also similar with Nili-Ravi milk, but the content of SFA was lower and UFA content was higher than Murrah milk. However, PUFA content in crossbreed's milk was lower than that of river buffalo. In brief, crossbreeding improved the milk quality and yield of Chinese swamp buffalo, but the crossbreed's milk has similar nutrition to the river buffalo such as Murrah and Nili-Ravi. [ABSTRACT FROM AUTHOR]

This paper presents a new constitutive model for cyclic loading of soil to predict the behavior of soft clays under undrained cyclic triaxial loading. It is inspired by the modified Cam-clay theory, and a new yield surface for elastic unloading is proposed to capture the soil behavior under cyclic loading. Only two additional parameters that characterize the cyclic behavior are used together with the traditional parameters associated with the modified Cam-clay constitutive model. The details of the relevant soil properties, initial states, and cyclic loading conditions are presented, and a computational procedure for determining the effective stresses and strains is demonstrated. The new model is used to simulate cyclic triaxial tests on kaolin, and the model predictions are generally found to be in agreement with the measured excess pore pressures and axial strains. Furthermore, numerous factors that influence the cyclic performance of soft soils can be considered in the new model, such as cyclic stress ratios, preshearing, and cyclic loading frequency. The critical cyclic stress ratio is also predictable using the proposed model in terms of excess pore pressures and axial strains. [ABSTRACT FROM AUTHOR]

Abstract  The ground freezing construction technique is one of the most effective and widely applied site construction methods in soft soil areas, like Shanghai. Some elevation-inclined refrigeration pipes are arranged for the artificial freezing excavation of the Pudong-side first-storey connection aisle, which is designed to connect two adjacent tunnel lanes of Shanghai East-Fuxing-Road tunnel project. No advanced research results could be found for computing the temperature field of tunnels and aisles frozen with inclined refrigeration pipes. Anyhow the computation of the relevant temperature field is of high importance for the safe and economical excavation of the above-mentioned aisle. In this paper, a method for computing the aisle temperature field using 3D FEM is given, and the computation accuracy is verified by contrasting the computed and site measured results. The back propagation neural networks are also applied to the temperature prediction using self-developed Neural Network-Expert System software, the predicted results are also very satisfactory. The mechanism during freezing and aisle excavation will be discussed on the basis of 3D FEM simulation. The authors believe that studying the parameter-sensitivity of temperature field is very important for the optimum selection of parameter values. So, in this paper, the parameter-sensitivity of temperature field is also discussed. In order to obtain the optimum frozen wall thickness, the relation between the frozen wall thickness and the initial freezing brine temperature is studied. At the end, an excavation pre-control plan is proposed by means of fuzzy logic theory for improving the excavation safety. The research result of the current paper is very helpful for projects that will be excavated by freezing construction technique. [ABSTRACT FROM AUTHOR]