Stress Analysis of Functionally Graded Isotropic Rotating Discs

The closed-form study deals with stress analysis of annular rotating discs made of functionally graded materials (FGMs) subjected to internal and external pressures. The elasticity modulus and density of the discs are assumed to varies radially according to three diverse power law functions, and it is assumed that the material is of constant Poisson's ratio. A gradient parameter n is chosen between - 0.5 and 1.00. When n equals to zero, the disc becomes isotropic disc case. Dimensionless tangential and radial stresses and radial displacements in the rotating discs are depicted in the Fig. s and tabulated in a table. In present study, it is investigated how to change the distributions of the stresses and displacements with the increasing gradient parameter n (with variation of elasticity modulus and density). For a design problems if someone wants a disc which is of a homogenous stress distribution, he should chose either Disc 3 with n=1.00 or Disc 1 with n=-0.50 for the lowest stress distribution according to the results of this study for the material producer or applicability of production of the materials.

Certified Reference Materials for the Characterisation of Multifunctional Materials

Multifunctional materials are created by intimately integrating different materials. The assessment of the local properties and composition of the different components of such a multifunctional material necessarily relies on techniques with sufficient spatial resolution. The increased use of these microanalysis or microprobe techniques has created a demand for appropriate quality assurance tools, such as reference materials. In this paper a number of issues related to the certification of reference materials for multifunctional materials are discussed. Examples of reference materials are shown to illustrate the particular challenges the reference material producer is faced with such as micro-homogeneity, minimum sample intake and stability.

Industrialization in the Middle East, Obstacles and Potential

Both public opinion and planners have generally emphasized and in some cases overestimated the importance of industrialization in the Middle East. Yet the needed research for sustained industrial development has lagged behind the desire for and interest in that sector and such research and literature are still in only the beginning phases.Literature on Middle East industrial development has been constrained by, (1) modern industrialization is a relatively new phenomenon in the region. (2) Analysis of industry and its related sophisticated technology is heavily dependent on quantitative measurements and data, the inadequacy of which is still a major obstacle to researchers and writers. (3) Even with the dominant feature of Middle Eastern economics--oil--authors have tended to deal with the region overwhelmingly as a raw material producer rather than as a center for refining and processing. These difficulties have led to two approaches in literature on the Middle East's industrialization.