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The aqueous and chloroform extracts obtained from leaves of Adhatoda vasica were evaluated for acaricidal activity against engorged females of Rhipicephalus microplus and their larvae. No significant mortality of adult ticks was observed in the tested concentration of aqueous extract except at 80%. Whereas, chloroform extract showed a dosedependent increase in adult mortality, and LC50 and LC90 values were determined as 10.47% and 11.74%, respectively. A significant difference in egg hatching of laid eggs was observed at all concentrations tested and 98.55% inhibition of hatching was observed at 12.5% concentration. Dose-dependent larval mortality was observed in larval immersion test with various concentrations of chloroform extract with LC 50 and LC 90 values of 0.51%, and 1.09%, respectively. The results indicate that the chloroform extract of Adhatoda vasica could have very good in vitro acaricidal activities on adult and larval stages of Rhipicephalus microplus ticks. [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]

As the required energy demand of humans keep increasing rapidly, the quest for developing new and efficient alternative energy resources progresses. Keeping the future energy crisis in mind, solar cells, particularly the low-cost dye and quantum dot sensitized solar cells seem to be a promising solution. Using solid polymer electrolyte in such solar cells proves to be a viable alternative as it contributes to the overall stability of the cell. However, there are certain details pertaining to solar cells where polymer electrolyte is used which have not yet been discussed in length. In this paper, we discuss the polarization effect of PEO-based quasi-solid electrolyte in DSSC and QDSC. [ABSTRACT FROM AUTHOR]

Health planning is generally considered a technical subject, primarily the domain of health officials with minimal involvement of community representatives. The National Rural Health Mission launched in India in 2005 recognized this gap and mandated mechanisms for decentralized health planning. However, since planning develops in the context of highly unequal power relations, formal spaces for participation are necessary but not sufficient. Hence a project on capacity building for decentralized health planning was implemented in selected districts of Maharashtra, India during 2010-13. This process developed on the platform of officially supported community-based monitoring and planning, a process for community feedback and participation towards health system change. A specific project on capacity building for decentralized planning included a structured learning course and workshops for major stakeholders. An evaluation of the project, including in-depth interviews of various participants and analysis of change in local health planning processes, revealed positive changes in intervention areas, including increased capacity of key stakeholders leading to preparation of evidence-based, innovative planning proposals, significant community oriented changes in utilization of health facility funds, and inclusion of community-based proposals in village, health facility-based block and district plans. Transparency related to planning increased along with responsiveness of health providers to community suggestions. A key lesson is that active facilitation of decentralized health planning and influencing the health system to expand participation, are essential to ensure changes in planning. Effective strategies included: identifying people's health service related priorities through community-based monitoring, capacity building of diverse stakeholders regarding local health planning, and advocacy to enable participation of community-based actors in the planning process. This combination of strategies draws upon the framework of 'empowered participatory governance' which necessitates combining a degree of 'countervailing power' and acceptance of participation by the system, for new forms of governance to emerge. [ABSTRACT FROM AUTHOR]

Mesoporous ZnO nanoparticles have been synthesized with tremendous increase in specific surface area of up to 578 m/g which was 5.54 m/g in previous reports (J. Phys. Chem. C 113:14676-14680, 2009). Different mesoporous ZnO nanoparticles with average pore sizes ranging from 7.22 to 13.43 nm and specific surface area ranging from 50.41 to 578 m/g were prepared through the sol-gel method via a simple evaporation-induced self-assembly process. The hydrolysis rate of zinc acetate was varied using different concentrations of sodium hydroxide. Morphology, crystallinity, porosity, and J- V characteristics of the materials have been studied using transmission electron microscopy (TEM), X-ray diffraction (XRD), BET nitrogen adsorption/desorption, and Keithley instruments. [ABSTRACT FROM AUTHOR]

A simple electrostatic model is applied to study the solvation energy and localization energy to inorganic semiconductor nanocrystallites trapped in polymer and ion conducting polymer electrolytes. The effective mass approximation has been applied to the system. In the single charge configuration, the dielectric constant of the medium has been identified as the selection criteria for hosting the nanoparticles. Solvation energy has been shown to depend on the host medium and the size of the crystallite. [ABSTRACT FROM AUTHOR]

Stress is believed to be the main driving force for whisker formation in Sn coatings on Cu. This suggests that whiskering can be suppressed by enhancing stress relaxation in the Sn layer, which is believed to be the reason why Sn-Pb alloys do not form whiskers. However, Pb is no longer acceptable for use in electronics manufacturing. As an alternative, we used pulsed plating to create Sn-Bi coatings with an equiaxed microstructure similar to that of Sn-Pb alloys. An optical wafer curvature technique was used to measure stress relaxation kinetics in Sn, Sn-Pb and Sn-Bi alloy thin films during thermal cycles. The results show that Sn-Bi films have significantly enhanced stress relaxation relative to pure Sn films. Comparison between Sn-Bi samples with equiaxed and columnar microstructures shows that both microstructure and alloy composition play a role in enhancing the stress relaxation. [ABSTRACT FROM AUTHOR]

Sn whisker and hillock formation is a reliability risk that has become increasingly important as the electronics industry has moved toward Pb-free manufacturing. To prevent them, we would like to understand what makes specific sites susceptible to deform into whiskers. We have used in situ scanning electron microscopy (SEM)/electron backscattering diffraction (EBSD) to monitor simultaneously the evolution of surface morphology and grain orientation in Sn surfaces in order to correlate whisker/hillock initiation with the underlying microstructure. Because rough films are difficult to measure with EBSD, we developed a unique procedure to make Sn-Cu samples with ultra-flat surfaces so that a large fraction of Sn grains can be indexed over repeated scans. We find that whiskers/hillocks grow from existing grains (not re-nucleated grains) with orientations close to (001). They often rotate from the as-deposited structure so that the orientation after growth does not indicate the orientation from which the whisker initiated. We measured the interface structure after removal of the Sn layer by chemical etching and found that there is no excessive accumulation of intermetallic compound around the whisker/hillock roots. Cross-sectional measurements revealed that a large fraction of the whiskers/hillocks have oblique boundaries underneath the surface, supporting the idea that these allow whiskers/hillocks to grow with lower stress. [ABSTRACT FROM AUTHOR]

Stress is believed to provide the driving force for growth of Sn whiskers, so stress relaxation in the Sn layer plays a key role in their formation. To understand and enhance stress relaxation in Sn-based films, the effects of Pb alloying and microstructure on their mechanical properties have been studied by observing the relaxation of thermal expansion-induced strain. The relaxation rate is found to increase with film thickness and grain size in pure Sn films, and it depends on the microstructure in Pb-alloyed Sn films. Measurements of multilayered structures (Sn on Pb-Sn and Pb-Sn on Sn) show that changing the surface layer alone is not sufficient to enhance the relaxation, indicating that the Pb enhances relaxation in the bulk of the film and not by surface modification. Implications of our results for whisker mitigation strategies are discussed. [ABSTRACT FROM AUTHOR]

Compressive stress due to intermetallic (IMC) growth appears to be the main driving force for whisker formation, but many of the underlying mechanisms relating the IMC to stress and whisker formation are not understood. To better understand these fundamental processes, we have measured IMC, stress and whisker evolution in Sn layers deposited on Cu. We present systematic results of the effect of changing the Sn layer structure by modifying the grain size, thickness, Pb content, microstructure, and IMC morphology/growth kinetics. We have also made corresponding measurements of the mechanical properties of the Sn with similar changes in the structure and composition without the growth of IMC. We show that modifications that enhance the stress relaxation in the Sn also lead to reduced whisker growth. [ABSTRACT FROM AUTHOR]

The electrical, structural, and photoelectrochemical properties of the polymer electrolyte PEO:NaI/I doped with an ionic liquid 1-ethyl 3-methylimidazolium dicyanamide (EMImDCN) have been reported. Incorporation of the ionic liquid (IL) increases the membrane homogeneity, decreased surface roughness, and enhances the short current ( J). Additionally, the doping of IL provides more charge carriers which enhances overall ionic conductivity (σ). The optimized σ was found at 40 wt.% IL composition. The fabricated DSSC using this new solid electrolyte showed 1.43% efficiency at 100 mW cm. [ABSTRACT FROM AUTHOR]

We report on real-time measurements that enable us to watch the morphology of whiskers and hillocks forming in real-time and provide insight into the mechanisms controlling their growth and initiation. These measurements show that whiskers appear to grow out of a single grain on the surface with little lateral growth. To understand why whiskers initiate at specific sites, we modified the surface using the focused ion beam to remove the oxide in selected areas. Whiskers did not grow out of these uncovered areas, indicating that the underlying grain structure is important to whisker growth and it is not sufficient to just remove the oxide barrier. In comparison with whiskers, we found that hillock formation is accompanied by a large amount of grain growth and often by grain rotation at the surface. [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]