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This paper presents the results of an investigation concerning the development of a turbulent boundary layer over a 2D symmetrical aerofoil and a 3D axisymmetric body with rigid and flexible surfaces. The experimental work included detailed measurements of the mean velocity profiles, pressure distribution, and drag force. The thin shear layer equations were solved numerically using a modified turbulence model to obtain the characteristics of the turbulent boundary layer. The results of this study indicate a significant difference between the characteristics of flow over rigid surfaces and those of flow over flexible surfaces of the same geometry. The mean velocity of flow in the case of flexible surfaces is smaller than the corresponding velocity of flow in the case of a rigid surface for a major part of the boundary layer. The boundary layer thicknesses are consistently higher on flexible surfaces than those on the corresponding rigid surfaces. Furthermore, in the case of flexible surfaces, drag reduction was always observed. The amount of reduction was seen to be systematically dependent on the characteristics of the flexible surface.

Ozone depletion remains one of the major social-political environmental issues of the day. Annual polar ozone depletion has been well documented, particularly in the southern hemisphere; as polar ozone depletion worsens annually, regions of lower latitude are increasingly affected in both the southern and northern hemispheres resulting in growing public awareness and concern. As stratospheric ozone decreases so does the protection it offers from harmful ultraviolet radiation. The grave consequences of unchecked ozone depletion on the Earth's biological systems has provided the impetus for a global research effort to determine the causes and effects of ozone depletion. To date, major attention has been given to ozone destruction cycles catalysed by the chemical by-products which result from the photolysis of man-made chlorofluorocarbons (CFCs) and nitrogen oxides. However in order to understand the underlying chemistry and physics of ozone depletion a wide range of laboratory studies and detailed theoretical calculations are also needed to characterize ozone dissociation dynamics and electronic structure. A full characterization of ozone spectroscopy and dissociation dynamics is far from complete. This is in part due to the difficulty in preparing such a reactive (and unstable) molecule for the necessary laboratory studies and partly due to the difficulty in accurately modelling ozone's ground state structure. Thus despite its crucial importance, studies of ozone spectroscopy and collision dynamics have only been refined within the last decade. In this review, the structure, spectroscopy and dissociation pathways of ozone will be discussed within the context of their role in the stratosphere.

This paper presents an investigation concerning a turbulent boundary layer over a flat plate with flexible surface. Experiments were carried out in a wind tunnel for a flat plate model with rigid as well as flexible surfaces. Detailed measurements of mean velocity profiles, pressure distribution, and drag force were taken. For numerical prediction of the turbulent boundary layer characteristics, thin shear layer equations were solved numerically by finite-difference technique using a modified turbulence model. Results of this study indicate a number of important differences between the characteristics of flow over rigid and flexible surfaces. The mean velocity of flow in the case of flexible surfaces is smaller than the corresponding velocity of flow in the case of rigid surface for major part of the boundary layer. The boundary-layer thicknesses are consistently higher on flexible surfaces than those on the corresponding rigid surface. Further, in the case of flexible surfaces, drag reduction has always been observed during the present study.

Second phase nanoinclusions of composition [Y.sub.2][Ba.sub.4]CuW[O.sub.y] (Y-24W1) are incorporated into the Y[Ba.sub.2][Cu.sub.3][O.sub.7-[delta]] (Y-123) superconducting matrix in order to form effective artificial flux pinning sites. The combined effect of Y-24W1 artificial defects and the addition of silver produce have increased the trapped fields in these samples.