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ABSTRACTThis paper presents the machining characteristics of AA6061/(0–9 wt%) ZrB2+ ZrC aluminium metal matrix composites using polycrystalline Diamond(PCD). In the present investigation, AMCs were fabricated by in situ reactions between K2ZrF6, KBF4and SiC particles. The electric stir casting furnace was used to fabricate the AMCs under a controlled environment. X-ray diffraction patterns (XRD) and field emission scanning electron microscope (FESEM) were used to ascertain the formation of ZrB2and ZrC particles in the AMCs. FESEM micrographs confirmed the uniform distribution of ZrB2and ZrC particulates along with good interfacial bonding with matrix aluminium alloy. The effect of varying wt% of ZrB2+ ZrC along with cutting speed, feed and depth of cut on machining forces and surface roughness were analysed. FESEM was used to study the morphology of cutting tool, machined surface and chip formation. It was observed that cutting forces reduce with increase in cutting speed due to decrease in built-up edge (BUE) formation and deprivation of dislocation density. The tool wear increased with increase in cutting speed, depth of cut and ZrB2+ ZrC content due to the increase in abrasive action of ceramic particles and reduction of stable BUE.

The recently proposed stabilization mechanism of the Randall–Sundrum metric gives rise to a scalar radion, which couples universally to matter with a weak interaction (≃1 TeV) scale. Demanding that gauge boson scattering as described by the effective low-energy theory be unitary up to a given scale leads to significant constraints on the mass of such a radion.

Beginning in the mid-1950s, much progress has been made in studying various aspects of the genetics of mosquitoes, particularly involving several species of three principal genera,Aedes, CulexandAnopheles, that transmit important human diseases. Here I discuss selected areas of research involving formal genetics; genome structure, organization and evolution at the interspecific and intraspecific level; and evolutionary genetics of theAedes scutellarisgroup. Information and insights gained from in-depth analyses of these areas, particularly transmission genetics, cytogenetics and genetics of chromosomal rearrangements, and of mutagen-induced sexual sterility, have proved invaluable for the development of the theory and evaluation of feasibility of genetic control of natural populations. As a result, mosquitoes represent some of the best studied taxa at various levels of genetic organization. Recent developments in molecular genetics offer exciting possibilities for extension of these concepts.

We present an interpretation of the recently observed phenomenon of rise of associated multiplicity with momentum transfer as an overlap effect of two independent physical processes, the first one dominating the small momentum transfer region and the second one correspondingly the large angle region.