Low Angle (low + angle)

Distribution by Scientific Domains


Selected Abstracts


Studies on the structural, thermal and optical behaviour of solution grown organic NLO material: 8-hydroxyquinoline

CRYSTAL RESEARCH AND TECHNOLOGY, Issue 2 2007
N. Vijayan
Abstract Single crystal of 8-hydroxyquinoline (8HQ) having chemical formula C9H7NO, an organic nonlinear optical (NLO) material has been successfully grown by slow evaporation solution growth technique at room temperature. The crystal system has been confirmed from the powder X-ray diffraction (PXRD) analysis. The crystalline perfection was evaluated by high resolution X-ray diffractometry (HRXRD). From this analysis we found that the quality of the crystal is quite good. However, a very low angle (tilt angle 14 arc sec) boundary was observed which might be due to entrapping of solvent molecules in the crystal during growth. Its optical behavior has been examined by UV-Vis. analysis, which shows the absence of absorbance between the wavelengths ranging from 400 to 1200 nm. From the thermal analysis it was observed that the material exhibits single sharp weight loss starting at 113°C without any degradation. The laser damage threshold was measured at single shot mode and the SHG behavior has been tested using Nd:YAG laser as a source. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


Microtexture and Grain Boundaries in Freestanding CVD Diamond Films: Growth and Twinning Mechanisms

ADVANCED FUNCTIONAL MATERIALS, Issue 24 2009
Tao Liu
Abstract Three groups of free-standing chemical vapor deposition (CVD) diamond films formed with variations in substrate temperature, methane concentration, and film thickness are analyzed using high-resolution electron back-scattering diffraction. Primarily {001}, {110}, and {111} fiber textures are observed. In addition, corresponding primary and higher order twinning components are found. As interfaces, high angle, low angle, primary twin, and secondary twin boundaries are observed. A growth and a twinning model are proposed based on the sp3 hybridization of the bond in the CH4 molecule that is used as the deposition medium. [source]


Microseismicity and faulting geometry in the Gulf of Corinth (Greece)

GEOPHYSICAL JOURNAL INTERNATIONAL, Issue 2 2000
Denis Hatzfeld
During the summer of 1993, a network of seismological stations was installed over a period of 7 weeks around the eastern Gulf of Corinth where a sequence of strong earthquakes occurred during 1981. Seismicity lies between the Alepohori fault dipping north and the Kaparelli fault dipping south and is related to both of these antithetic faults. Focal mechanisms show normal faulting with the active fault plane dipping at about 45° for both faults. The aftershocks of the 1981 earthquake sequence recorded by King et al. (1985) were processed again and show similar results. In contrast, the observations collected near the western end of the Gulf of Corinth during an experiment conducted in 1991 (Rigo et al. 1996), and during the aftershock studies of the 1992 Galaxidi and the 1995 Aigion earthquakes (Hatzfeld et al. 1996; Bernard et al. 1997) show seismicity dipping at a very low angle (about 15°) northwards and normal faulting mechanisms with the active fault plane dipping northwards at about 30°. We suggest that the 8,12 km deep seismicity in the west is probably related to the seismic,aseismic transition and not to a possible almost horizontal active fault dipping north as previously proposed. The difference in the seismicity and focal mechanisms between east and west of the Gulf could be related to the difference in the recent extension rate between the western Gulf of Corinth and the eastern Gulf of Corinth, which rotated the faults dipping originally at 45° (as in the east of the Gulf) to 30° (as in the west of the Gulf). [source]


Growth of Co/Cu multilayered thin films by electro-deposition

PHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 8 2004
Y. Hayashi
Abstract Electrochemical method has been applied for preparing Co/Cu multilayered thin films. The layers were electrodeposited after injecting Co and Cu containing solutions in a flow exchanged supporting electrolyte solution. In X-ray diffraction at low angle range a long period peak could be observed, and in the middle angle region a single broad peak showing an average lattice spacing of the film was observed. The electrical resistance showed the properties of Giant Magnetoresistance (GMR). The GMR ratio showed a variation against Cu layer thickness as expected for anti-ferromagnetically coupled films. The maximum GMR ratio obtained in this study was 6.2% at room temperature for the film of [Co 2.0 nm/Cu 1.0 nm]15. Though we need further studies for choosing suitable deposition conditions, the electrodeposition method is a promising method for producing multilayered thin films. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


Enamel ridge alignment in upper molars of ruminants in relation to their natural diet

JOURNAL OF ZOOLOGY, Issue 1 2010
T. M. Kaiser
Abstract Although it is generally thought that dental design reflects mechanical adaptations to particular diets, concrete concepts of such adaptations beyond the evolution of hypsodonty are largely missing. We investigated the alignment of enamel ridges in the occlusal molar surface of 37 ruminant species and tested for correlations with the percentage of grass in the natural diet. Independent of phylogenetic lineage, species that were either larger and/or included more grass in their natural diet showed a higher proportion of enamel ridges aligned at low angles to the direction of the chewing stroke. Possible explanations for this design are a potential alignment of grass blades in parallel to the molar tooth row, a potential increased proportion of a propalinal (anterior,posterior) chewing movement in grazers as opposed to a strictly transversal chewing stroke in browsers and the general distribution of forces along the occlusal surface during the chewing stroke. The latter will be less heterogenous (with less force peaks) with an increasing proportion of low-angle enamel ridges. While the validity of these explanations will have to be tested in further studies, the enamel ridge alignment represents a clear signal that deviates from an arbitrary distribution and hence most likely represents a functional adaptation. [source]