In this paper, we base a theory established in an impulse-energy level to solve a problem of a disk-bail system, in which a moving ball collides perpendicularly against an disk staying on a horizontal surface. The imp...In this paper, we base a theory established in an impulse-energy level to solve a problem of a disk-bail system, in which a moving ball collides perpendicularly against an disk staying on a horizontal surface. The impact process is an ensemble con- sisting of a point impact coupled with a line contact between bodies of the disk, the ball and the fixed horizontal surface. We experimentally and theoretically show that the post-impact states of the disk dramatically vary with the impacting position of the ball. Explanations are given by investigating the evolutions of the potential energies resided in the points involved in the complex frictional impacts. Good agreements between numerical and experimental results strongly suggest that the evolution of energy together with the dissipation must be reflected in mathematical models if a precise description for the post-impact state of systems is expected.展开更多
A technique of treating steel with rare earth fluoride complex additives(REFCA),effects and influnce factors have been studied.REFCA play a role on controlling inclusion morphology,purifying the molten steel and impro...A technique of treating steel with rare earth fluoride complex additives(REFCA),effects and influnce factors have been studied.REFCA play a role on controlling inclusion morphology,purifying the molten steel and improving properties of steel.The optimum composition of REFCA is REF_3 42%;CaO 33%;SiCa 25%,and the amount of REF_3 is 0.5 wt%～0.6 wt% of steel.展开更多
Discharge of whey proteins is still a current practice by small cheese producers. The development of low-cost alternatives for recovery of these proteins is fundamental for small producers who cannot apply expensive t...Discharge of whey proteins is still a current practice by small cheese producers. The development of low-cost alternatives for recovery of these proteins is fundamental for small producers who cannot apply expensive techniques. The present study investigated the complex coacervation technique as a cheap technology to recover proteins from sweet whey using carboxymethylcellulose, and the coacervate used as an ingredient in the formulation of probiotic fermented milk. The nutritional properties of whey-carboxymethylcellulose coacervates (WP-CMC) were evaluated in trials with animals (rats) using casein as a reference. All these parameters—the coefficient of feed efficiency (CEA), protein digestibility-corrected amino acid score (PDCAAS), and net protein ratio (NPR), as well as weight gain—were determined to evaluate protein quality. A sensory acceptance test was applied to evaluate the sensory characteristics of the product. The complex coacervation technique recovered 86% of the protein from sweet whey. No significant (p > 0.05) differences were observed in the biological tests for both groups (WP-CMC and Casein groups) when NPR (4.98 to 5.04), digestibility (92.35 to 90.64), and CEA (0.40 to 0.42) were evaluated. Probiotic fermented milk beverage containing WP-CMC (0.78%) and guar gum (0.68%) presented good acceptability as determined by sensory evaluation. WP-CMC can be considered an ingredient with high nutritional and biological value that could be applied in probiotic fermented milk as an alternative to small producers to allocate the residual whey from cheese manufacture.展开更多
基金supported by the National Natural Science Foundation of China (Grant No.11132001)
文摘In this paper, we base a theory established in an impulse-energy level to solve a problem of a disk-bail system, in which a moving ball collides perpendicularly against an disk staying on a horizontal surface. The impact process is an ensemble con- sisting of a point impact coupled with a line contact between bodies of the disk, the ball and the fixed horizontal surface. We experimentally and theoretically show that the post-impact states of the disk dramatically vary with the impacting position of the ball. Explanations are given by investigating the evolutions of the potential energies resided in the points involved in the complex frictional impacts. Good agreements between numerical and experimental results strongly suggest that the evolution of energy together with the dissipation must be reflected in mathematical models if a precise description for the post-impact state of systems is expected.
文摘A technique of treating steel with rare earth fluoride complex additives(REFCA),effects and influnce factors have been studied.REFCA play a role on controlling inclusion morphology,purifying the molten steel and improving properties of steel.The optimum composition of REFCA is REF_3 42%;CaO 33%;SiCa 25%,and the amount of REF_3 is 0.5 wt%～0.6 wt% of steel.
文摘Discharge of whey proteins is still a current practice by small cheese producers. The development of low-cost alternatives for recovery of these proteins is fundamental for small producers who cannot apply expensive techniques. The present study investigated the complex coacervation technique as a cheap technology to recover proteins from sweet whey using carboxymethylcellulose, and the coacervate used as an ingredient in the formulation of probiotic fermented milk. The nutritional properties of whey-carboxymethylcellulose coacervates (WP-CMC) were evaluated in trials with animals (rats) using casein as a reference. All these parameters—the coefficient of feed efficiency (CEA), protein digestibility-corrected amino acid score (PDCAAS), and net protein ratio (NPR), as well as weight gain—were determined to evaluate protein quality. A sensory acceptance test was applied to evaluate the sensory characteristics of the product. The complex coacervation technique recovered 86% of the protein from sweet whey. No significant (p > 0.05) differences were observed in the biological tests for both groups (WP-CMC and Casein groups) when NPR (4.98 to 5.04), digestibility (92.35 to 90.64), and CEA (0.40 to 0.42) were evaluated. Probiotic fermented milk beverage containing WP-CMC (0.78%) and guar gum (0.68%) presented good acceptability as determined by sensory evaluation. WP-CMC can be considered an ingredient with high nutritional and biological value that could be applied in probiotic fermented milk as an alternative to small producers to allocate the residual whey from cheese manufacture.
