Morphology and Photoluminescence of HfO2Obtained by Microwave-Hydrothermal

In this letter, we report on the obtention of hafnium oxide (HfO2) nanostructures by the microwave-hydrothermal method. These nanostructures were analyzed by X-ray diffraction (XRD), field-emission gum scanning electron microscopy (FEG-SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectrometry (EDXS), ultraviolet–visible (UV–vis) spectroscopy, and photoluminescence (PL) measurements. XRD patterns confirmed that this material crystallizes in a monoclinic structure. FEG-SEM and TEM micrographs indicated that the rice-like morphologies were formed due to an increase in the effective collisions between the nanoparticles during the MH processing. The EDXS spectrum was used to verify the chemical compositional of this oxide. UV–vis spectrum revealed that this material have an indirect optical band gap. When excited with 488 nm wavelength at room temperature, the HfO2nanostructures exhibited only one broad PL band with a maximum at around 548 nm (green emission)

Effect of TiB<SUB>2</SUB> particles on sliding wear behavior of Al-4Cu alloy

Dry sliding wear of Al-4Cu-xTiB<SUB>2</SUB> (x = 0, 2.5, 5, 7.5 and 10 wt.%) in situ composites have been studied in the peak-aged condition using a pin-on-disc wear testing machine at different loads. The composites were prepared by the reaction of a mixture of K<SUB>2</SUB>TiF<SUB>6</SUB> and KBF<SUB>4</SUB> salts with molten alloy. The results indicate that TiB<SUB>2</SUB> particles markedly improve the wear performance of the Al-4Cu alloy. The wear resistance increases with increase in the amount of TiB<SUB>2</SUB>. The load bearing capacity of the alloy during wear increases in presence of TiB<SUB>2</SUB> particles. Study of the wear surfaces and debris of both alloy and composites using the scanning electron microscope suggests that the improvement in wear resistance is mainly due to the formation of finer debris

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Not AvailableThe purpose of this study was to ascertain shell occupation patterns by the hermit crab; Diogenes alias found inhabiting the subtidal region of Mumbai, northwest coast of India. A total of 385 samples of D. alias, occupying different molluscan shells, were collected bi-weekly from trawling operations off Mumbai. The species was found to occupy the shells of 12 gastropods species, of which, the most commonly occupied shells were that of Tibia curta (38.7 %) followed by Indothais lacera (36.37 %) while the shells of Rapana rapiformis and Turris spp. were least occupied with 0.26 %. The diversity of shells occupied by male was higher than female and least in ovigerous females. A high correlation was found between the internal volume of shell and weight of hermit crab occupying it. The present study concluded that the shell architecture has influence on the shell occupation by hermit crabs.Not Availabl

Bodies: corporeality and embodiment in childhood and youth studies

The body has become a key theme of academic study across disciplines of sociology, cultural studies, anthropology, and psychology. Although the body has become a central focus of much theoretical work, in childhood and youth studies, the physicality and materiality of the body is more often than not taken for granted or is an &quot;absent presence.&quot; The body often remains implicit or as a site upon which societal inequalities play out, rather than an active force. Where the body is directly addressed in studies of childhood and youth, it is often identified as the site of social or cultural &quot;problems,&quot; such as in the growing alarm surrounding rates of childhood obesity and poor body image. Theories of embodiment aim to place the body and embodied experience at the forefront of analysis to highlight the active relations between bodies and the social world and to correct previous approaches in which the body is invisible or rendered inferior to the mind in a binary logic. Theories of the body have implications for research in childhood and youth studies, as all major &quot;structural&quot; inequalities such as gender, class, race, sexuality, disability, and place are necessarily embodied. This section places bodies at the center of discussions in the study of childhood and youth