10,730 research outputs found

    Reviving Gujarat State Road Transport Corporation: An Agenda for Action

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    In this article, we examine in detail the reasons related to the declining operating and financial performance of Gujarat State Road Transport Corporation (GSRTC). The contribution of various environmental and governance issues related to the decline of GSRTC are identified. Based on the diagnosis, a detailed revival plan consisting of a set of actions to be undertaken by the management is proposed. The responsibilities of the government, the management, and the employees in implementing the revival plan are briefly discussed. This article concludes with set of strategic priorities that need to be examined by government in reviving GSTRC and other similar state-owned public utilities.

    Elasticity-mediated self-organization and colloidal interactions of solid spheres with tangential anchoring in a nematic liquid crystal

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    Using laser tweezers and fluorescence confocal polarizing microscopy, we study colloidal interactions of solid microspheres in the nematic bulk caused by elastic distortions around the particles with strong tangential surface anchoring. The particles aggregate into chains directed at about 30 degrees to the far field director and, at higher concentrations, form complex kinetically trapped structures. We characterize the distance and angular dependencies of the colloidal interaction forces.Comment: 6 pages, 5 figure

    Removal of toxic metals from solution by leaf, stem and root phytomass of Quercus ilex L. (holly oak)

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    Increased consciousness for safeguarding the aqueous environment has prompted a search for alternative technologies for the removal of toxic metal ions from aqueous solutions. In this regard, a wide variety of biomass is being considered as adsorbents of heavy metals for treatment of industrial and domestic wastewaters as well as natural waters, including drinking water. In the present investigation, the potential of Quercus ilex phytomass from stem, leaf and root as an adsorbent of chromium (Cr), nickel (Ni), copper (Cu), cadmium (Cd) and lead (Pb) at ambient temperature was investigated. The metal uptake capacity of the root for different metals was found to be in the order: Ni>Cd>Pb>Cu>Cr; stem Ni>Pb>Cu>Cd>Cr; and leaf Ni>Cd>Cu>Pb>Cr. The highest amount adsorbed was Ni (root>leaf>stem). Data from this laboratory demonstrated that Ni is sequestered mostly in the roots, where concentrations can be as high as 428.4 ng/g dry wt., when 1-year-old seedlings were treated with Ni (2000 mg/l) in pot culture experiments, compared to 7.63 ng/g dry wt., control (garden and greenhouse soil) topsoil where Ni was present in trace amounts. This proves that the root biomass of Q. ilex has the capacity for complexing Ni. Cr exhibited the least adsorption values for all the three types of phytomass compared to other metals. The trend of adsorption of the phytomass was similar for Ni and Cd, i.e. root>leaf>stem. Desorption with 10 mM Na4 EDTA was effective (55-90%) and, hence, there exists the possibility of recycling the phytomass. The biosorption results of recycled phytomass suggest that the selected adsorbents are re-usable. The advantages and potential of the Q. ilex phytomass as a biofilter of toxic trace metals, the scope and need for enhancing the efficiency of the Q. ilex phytomass as an adsorbent of metals are presented.http://www.sciencedirect.com/science/article/B6VB5-40NFSK0-B/1/2e726350ef28f37aa6dd7fc8ababc91

    Influence of exogenous urea on photosynthetic pigments, 14CO2 uptake, and urease activity in Elodea densa-environmental implications

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    This paper analyzes the effect of exogenous urea in increased concentration gradient (0, 100, 500 and 1,000 mg L-1) on photosynthetic pigments (measured spectrophotometrically), uptake of 14CO2 (using radioisotope), and urease activity (by measuring ammonia with Nessler's reagent) in leaves of Elodea densa Planch. We have observed that low concentration of urea (100 mg L-1) stimulates the accumulation of photosynthetic pigments and intensifies photosynthesis in E. densa, whereas high concentration (1,000 mg L-1) suppresses these processes. Urease activity increased by approximately 2.7 and 8 fold when exogenous urea concentrations were 100 and 500 mg L-1, respectively. However, exogenous urea in high concentration (1,000 mg L-1) decreased urease activity by 1.5 fold compared to the control. The necessity of mitigating urea and other nitrogen-containing compounds (NH3 from urea) in water bodies has been discussed with emphasis on the potential for phytoremediation of urea using common water weed viz. E. densa. © 2013 Springer-Verlag Berlin Heidelberg

    Experimental Investigation of Land Mobile Prediction Methods and Modeling of Radio Planning Tool Parameters along Indian Rail Road Rural Zones

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    Mobile communication networks in rural zones were not given enough importance and emphasis unlike their urban counter parts due to the unattractive revenues and economic considerations for the cellular operators. In order to identify the suitable prediction methods for Indian rail road rural zones, train-based measurements were conducted in the northern and western rural zones along rail roads. These were carried out by recording the carriers emitted by the trackside base stations inside the moving train. The observed signal levels converted into path losses were compared initially with various conventional prediction methods. The observed results were also compared with the predicted results of radio planning tool utilizing digital terrain data. The constants of the model incorporated in the radio planning tool were tuned separately for north Indian and west Indian base stations based on the observed results. The suitability of the models has been evaluated in terms of standard statistical parameters

    Effect of Annealing on Hardness and Elastic Modulus of Invar36 Thin Films Deposited by Direct Current Sputtering for Strain Gauge Applications

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    Invar36 thin film was deposited at room temperature on p-type silicon (100) substrates using DC magnetron sputtering technique. In order to investigate the post-annealing effect on the structural characteristics and mechanical properties of the prepared films, they were vacuum annealed for one hour at different temperatures viz. 200°C, 400°C and 500°C. Composition analysis, phase structure, microstructure and roughness of as-deposited and annealed Invar36 thin films were investigated by energy dispersive X-ray analysis (EDX), X-Ray diffraction (XRD) and Atomic Force Microscopy (AFM). Mechanical properties of Invar36 thin films were studied by nano indentation method. EDX analysis revealed a variation in nickel content with annealing. The XRD measurements indicated the phase transformation of Invar36 thin film with annealing. AFM analysis implied uniform surface morphology of the films, increase of surface roughness and grain size with annealing. The hardness (H) of the film decreased with annealing. Hardness of as-deposited, annealed at 200oC, 400oC and 500oC were found as 8.5±0.96 GPa, 7.64±0.35 GPa, 6.34±0.14GPa and 3.95±1.05 GPa, respectively. The elastic modulus of Invar36 thin films was increased with annealing. Elastic modulus of as-deposited, annealed at 200oC, 400oC and 500oC were found as 157.00±25.49 GPa, 166.0±11.8 GPa, 172.00±9.93 GPa and 176.00 ±10.78 GPa, respectively. These results are explained on the basis of the change of microstructure after annealing and the effect of the same on the mechanical properties of Invar36 thin films for strain gauge applications

    Studies on K-Electron Capture Probability in the Decay of 95tc and 139Ce

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    A New Approach for SAR Image Denoising

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    In synthetic aperture radar (SAR)  imaging, the transmitted pulses from space born antenna interacts with ground objects and returned energy or back scattered energy will be collected  to get backscattered image. In this process, a speckle noise will be added because of the coherent imaging system and  makes the study of SAR images very difficult. For better SAR image processing, the speckle has to be removed in the initial stages of processing  and maintain all texture features efficiently. The BM3D method is generally considered as state of art method in denoising of SAR images. In this paper, it is proposed a technique to despeckle the speckle noise to the maximum extent while maintaining the edge characteristics
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