Volume 1, Number 2
PROPAGATION OF WEAK DISCONTINUITIES
ABSTRACT:
The transport equations representing the rate of change of discontinuities in the normal derivatives of the flow variables are obtained along bicharacteristic curves in the characteristic manifold of the differential equations governing the flow of a chemically reacting gas. The propagation of these weak discontinuities is discussed in particular cases of plane, cylindrical and spherical geometry. The effects of the chemical reactions, the magnitude of initial discontinuity, the initial curvature of the wave front and the upstream flow Mach number on the propagation of these weak discontinuities are investigated.
SONIC CONDITIONS FOR SELF-SUSTINED DETONATION WAVE
ABSTRACT:
The generalized sonic conditions for a three-dimensional unsteady self-sustained detonations wave are derived by defining sonic locus as a limiting characteristic surface of the governing hyperbolic equations embedded in the reactive zone at a finite distance behind the shock. Two compatibility conditions are derived by considering Whitham’s shock ray co-ordinate system as a front attached co-ordinate, which are necessary to determine the motion of both the lead shock and the sonic surface. The domain of influence of reactive zone is bounded by two surfaces; the lead shock surface and the trailing characteristic surface. The geometry of these two surfaces plays an important role in the underlying dynamics.
ANALYTICAL EXPRESSIONS OF THE VARIABLE VISCOSITY
ABSTRACT:
In this paper, we investigate first and second law of thermodynamic analysis of variable viscosity hydromagnetic, which has Couette flow with permeable walls. The analytical expressions of the dimensionless velocity and dimensionless temperature are derived by using the Homotopy analysis method. Our analytical expression of the dimensionless velocity is compared with the exact solution and a satisfactory agreement is noted. We also derive the analytical expressions for skin friction coefficient, Nusselt number, Entropy generation rate, Bejan number. The HAM contains the convergence control parameter, so we can easily extend to solve other MHD fluid flow problem in engineering and science.
USE OF PROTEIN ISOLATE FROM FISH WASTE
ABSTRACT:
Fish processing is a crucial sector to meet the nutrient needs for humans, but it generates a significant amount of the estimated 50% of total waste. It follows the same time a problem of dumping of waste in different environments which increases environmental pollution and in particular the water environment. Our work aims to study the physicochemical quality of sardine waste (edges, heads and guts). Then, we seek to exploit these coproducts as medium culture for microorganisms such as Lactobacillus and E. coli. In this case, two universal mediums were prepared with the isolate obtained from fish in the place of peptones of the conventional mediums. The physicochemical analyzes showed that the isolate obtained has a high biological value (rich in essential amino acids). The results indicate that the use of this isolate must be accompanied with other essential elements of culture (vitamin compounds, essential amino acids, minerals) as growth factors to optimize the growth of bacteria involved. This work allowed us to have a recovery method that reduces the risk of pollution caused by discharges of different fish processing industries and we contribute to the development of biotechnology.
A GREAT DISCOVERY ALLERGY AND ASTHMA
ABSTRACT:
Background. Allergic asthma and rhinitis, atopic dermatitis, urticaria and food allergy are genetic diseases of infants and children. Several investigators have provided evidence for a genetic localization for atopy. Babies of atopic parents are at high risk of developing atopic diseases, however the phenotypic expression of such diseases varies widely, being very mild in some infants and children, severe and frustrating in many, even life-threatening in others, being also common,disabilitating, and chronic.