•Bi1-xCoxTe3 nanomaterials were prepared by microwave synthesis technique.•Quantum interference and electron–electron interaction dominated transport at low temperature.•Linear fit in Δσ(T) vs ln(T) ...curve results positive slope (k), and negative screening factor (F).•Phase coherence length (lφ) decreases with the increasing the cobalt incorporation.•Reduction of Seebeck coefficient (S) with increase in cobalt concentration.
Magnetotransport and thermoelectric properties of Bi2-xCoxTe3 nanomaterials have been studied. Temperature-dependent electrical resistivity of the materials shows a drastic change from degenerate semiconductor to a metal-like behavior with incorporation of cobalt in the sample. The observation of T and ln(T) dependent electrical conductivity is predicted to have electron–electron interaction (EEI), and quantum interference effect (QIE) dominated transport mechanisms respectively. Low field MR of the materials exhibits sharp dips demonstrating the appearance of QIE, and a crossover from linear MR at low temperature to linear plus quadratic MR at high temperature indicates the quantum transport of the materials. Quantum correction of the low field magnetoconductivity follows 2D Hikami-Larkin-Nagaoka equation and the temperature variation of phase coherence length lφ indicates the existence of 2D transport in the materials. The decrease of phase coherence length and increase of α parameter with the incorporation of cobalt leads to the enhancement of bulk domination of the conduction.
The mechanical properties of Ti alloys are significantly affected by the introduction of solute or impurity elements. Thus, the role of impurities on the hardening or softening behavior of α-Ti was ...investigated through first principles calculations. In particularly, to provide a comprehensive electronic and atomic basis of solute addition in α-Ti, the effect of metallic (V and Al) and non-metallic (C and O) impurities on the ideal shear strength (ISS) and generalized stacking fault energy (GSFE) across different slip systems of Ti were probed. The results revealed that the addition of V atom reduces both ISS and unstable stacking fault energy across various slip systems of α-Ti, whereas Al addition increases the ISS of Ti. Further, the addition of O atom decreases ISS for most of the slip systems while C solute atom increases ISS across all slip systems of α-Ti. To illustrate the underlying factors influencing the observed softening/strengthening behavior, the electronic density of states and valence charge transfer were determined. The electronic density of states calculations showed that the contribution from the d states of V atom decreases the stability of Ti-V solid solution, thereby leading to a decrease in the plastic anisotropy of α-Ti. Finally, the shearability parameter and critical resolved shear stress (CRSS) ratios across different slip systems of Ti solid solutions were calculated to understand the macroscopic effects of impurity addition on the deformation behavior of α-Ti at ambient conditions. Overall, the first-principles study provides an insight into the electronic basis of strengthening/softening effect of solute addition in α-Ti and assesses their implications on the deformation behavior of α-Ti alloys.
•Impact of impurities on plastic deformation of Ti was investigated.•Non-metallic solutes increase pyramidal 〈c+a〉 slip activity.•Metallic impurities reduce the plastic anisotropy in α-Ti.
The fast rise of wireless communications necessitates effective cellular network planning. It is a challenging effort to figure out the ideal network of antennas over a broad area, and it is a ...spatial choice problem that often relies on a variety of geographic characteristics derived from environmental, economic, and social datasets. GIS is the greatest platform for combining all of these criteria into a single map that can be readily studied and processed to find the optimum location. A multistage optimized site suitability modeling approach using the Spatial Analyst toolbox and Fuzzy Logic toolbox has been developed to search for optimal suitable locations for new base transceiver station (BTS) sites of the Bharat Sanchar Nigam Limited (BSNL) network in Pithoragarh District of Uttarakhand State. The proposed model took into account nine decision parameters: slope, population, tourist destinations, highways, rivers, reserved forests, land use-land cover, current tower locations, and coverage areas. The model’s first stage looks for suitable ground with a gradual slope and then prohibits the restricted areas from the search ring. The next stage searches the network for high-demand zones. And the final stage employs a set of 25 fuzzy rules to ensure that it meets both land and demand appropriateness criteria at the same time. Overall for the Pithoragarh District, nine new optimal BTS locations are proposed. Finally, the results are validated by cross-checking the values of decision criteria for all new proposed locations. The new BTS locations are proved to be the best sites in terms of slope, elevation, and distance between the two closest sites and distance from the nearest road. These new sites will provide network coverage to 22 uncovered villages. With new suggested sites, proximity to roads and tourist places can be reduced.
Purpose: To evaluate the astigmatism correcting effect of penetrating arcuate keratotomy (AK) done during femtosecond laser-assisted cataract surgery (FLACS). Methods: In this nonrandomized ...prospective study, 80 eyes of 70 patients were studied. The study included patients who underwent combined FLACS and AK, with corneal astigmatism ranging from 0.4 to 1.5 diopters (D). Femtosecond laser-assisted penetrating arcuate keratotomies were created at 8 mm optical zone at 80% depth and were centered at the limbus. Keratometric astigmatism was measured prior to and 3 months post-surgery. Vector analysis was performed using Power vector analysis method. Results: The mean preoperative keratometric astigmatism without accounting for axis was 0.85 ± 0.27 D, which reduced significantly to 0.47 ± 0.27 D at 3-month follow-up. The mean astigmatism correction attained without accounting for axis was 0.38 ± 0.32 D. The vector corrected mean preoperative astigmatism was 0.85 ± 0.27 D which reduced significantly to 0.50 ± 0.31 D postoperatively (P < 0.001, 95% CI). Vector corrected mean astigmatism correction attained was 0.35 ± 0.38 D. There were no significant intraoperative or postoperative complications. Conclusion: Preexisting astigmatism can be tackled effectively with penetrating AK during FLACS although under correction is observed with present nomograms. Further refinements may achieve better correction.
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