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We have performed X-ray synchrotron micro-diffraction measurements to study the processes controlling the formation of hillocks and whiskers in Sn layers on Cu. The studies were done in real-time on Sn layers that were electro-deposited immediately before the X-ray measurements were started. This enabled a region of the sample to be monitored from the as-deposited state until after a hillock feature formed. In addition to measuring the grain orientation and deviatoric strain (via Laue diffraction), the X-ray fluorescence was monitored to quantify the evolution of the Sn surface morphology and the formation of intermetallic compound (IMC) at the Sn-Cu interface. The results capture the simultaneous growth of the feature and the corresponding film stress, grain orientation, and IMC formation. The observations are compared with proposed mechanisms for whisker/hillock growth and nucleation. [ABSTRACT FROM AUTHOR]

Carbohydrate-based surfactants (CBS) are an important class of amphiphilic compounds containing both hydrophilic and lipophilic moieties. These natural surfactants are biosynthesized within living cells and also easily can be prepared synthetically from the most abundant carbohydrate-rich renewable vegetable raw materials such as cellulose, pectin, hemicellulose, starch, etc. and fatty materials by sequential reactions. Extensive exploitation of non-renewable fossil fuels such as coal, petroleum; natural gas etc. damages the human and ecological health with significant contribution in overall pollution, thus the quest for novel methods and strategies has been accelerated to replace the conventional non-renewable fossil fuel sources with renewable, biodegradable, as well as sustainable sources for surfactant production. In this scenario, carbohydrate surfactants are of great interest because they are naturally abundant, biocompatible, highly biodegradable, and not noxious for the environment, which makes them an excellent alternative to surfactants from petrochemical sources. [ABSTRACT FROM AUTHOR]

There are numerous studies which indicate that association exist between Spiro metric indices (FEVI, FEVI/ FVC%, FVC, FEF 25-75%, PEFR) and hypertension. It is quite visible that the people who is suffering from hypertension as well as IHD might have very higher probability of having OAD. Present research has attempted the objective of finding the occurrences of OAD specifically when it has been found that any patient is having IHD along with hypertension. The present research has also attempted the comparison when the the patient is not having the hypertension and are healthy. Such study was carried out because in the views of researchers no such previous study was carried out in this area. [ABSTRACT FROM AUTHOR]

For new risk factors to be meaningful in disease prevention in any population, they must either be responsible for a substantial proportion of the disease burden, or their modification must have a tangible impact on disease prevalence in that population. The major known variable risk factors also describe at least 75% of new cases of cardiovascular disease in the Western world. Physicians and their patients must therefore not lose sight of the fact that lifestyle changes incorporating smoking cessation, a heart healthy diet, weight reduction and regular physical activity together with drug therapy for dyslipidaemia, still remain the cornerstones of CVD prevention in our population. The routine measurement of plasma homocysteine and the use of specific therapies directed at reducing elevated levels is not yet recommended. [ABSTRACT FROM AUTHOR]

A series of Gd3+-doped BaMgAl10O17 phosphors have been successfully synthesized using a low-temperature solution combustion method. The crystal structure and phase purity of the samples were characterized using x-ray powder diffraction analysis. The optimal concentration of Gd3+ dopant in BaMgAl10O17 was determined through measurements of the photoluminescence spectra of the phosphors. All phosphors showed narrowband UVB emission at 313 nm with excitation wavelength at 272 nm. Relatively dominant electron spin resonance (ESR) lines were observed with geff ≈ 1.98. 2.7, 4.2, and 5.95 in phosphors with low concentration of dopant Gd3+ ion. At higher dopant concentrations, the spectrum appeared to be U-like with prominent lines at geff ≈ 1.99, 2.7, 4.2, and 5.94. Distortions in the neighborhood of Gd3+ ion led to ESR lines in the low-field region of the spectrum. [ABSTRACT FROM AUTHOR]

We use finite element simulations to quantitatively evaluate different mechanisms for the generation of stress in Sn films due to growth of the Cu6Sn5 intermetallic phase at the Cu-Sn interface. We find that elastic and plastic behavior alone are not sufficient to reproduce the experimentally measured stress evolution. However, when grain boundary diffusion is included, the model results agree well with experimental observations. Examination of conditions necessary to produce the observed stresses provides insight into potential strategies for minimizing stress generation and thus mitigating Sn whisker growth. [ABSTRACT FROM AUTHOR]