Suchergebnisse

Most of the agricultural-tasks are involved with considerable drudgery. So, it is preferable to utilize more developed tools in agriculture. In this study, an evaluation was made on the drudgery-levels of farmers during harvesting of paddy in Odisha (India) in two cases, such as use of serrated-sickles for manually harvesting, and use of power tiller reaper. A reduction of 26.61% in drudgery-level was observed based on the measured ergonomic-parameters by power tiller reaper as compared to serrated-sickles. Further, correlation-coefficient matrix was obtained by considering the ergonomic-parameters for both the cases. Moreover, an attempt was made for the evaluation of adoption practices of the farmers by the use of "Adoption and Diffusion Outcome Prediction Tool (ADOPT)" to provide the prediction of an expected rate of practices as well as peak level of adoption by determining the significance of diverse factors that influence it. Then, the SWOT analysis was done for the power tiller reaper, which was followed by the opinions of farmers in to assess the suitability of both cases.

We report structure, vibrational properties, and weak antilocalization-induced quantum correction to magnetoconductivity in single-crystal Bi2GeTe4. Surface band-structure calculations show a single Dirac cone corresponding to topological surface states in Bi2GeTe4. An estimated phase coherence length, lΦ ~ to 143 nm and prefactor α~-1.54 from Hikami-Larkin-Nagaoka fitting of magnetoconductivity describe the quantum correction to conductivity. An anomalous temperature dependence of A1g Raman modes confirms enhanced electron-phonon interactions. Our results establish that electrons of the topological state can interact with the phonons involving the vibrations of Bi-Te in Bi2GeTe4. ; Funding Agencies|CSIRCouncil of Scientific & Industrial Research (CSIR) - India; SERBDepartment of Science & Technology (India)Science Engineering Research Board (SERB), India [CRG/2018/002197]; DST India grant [DST/INT/SWD/VR/P-18/2019]; Swedish Research Council (VR)Swedish Research Council [2016-03365, 2018-07070]; Knut and Alice Wallenberg Foundation through the Wallenberg Academy Fellows program [KAW 2020.0196]; Electron Microscopy Laboratory at Linkoping University; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; Swedish Energy AgencySwedish Energy AgencyMaterials & Energy Research Center (MERC) [46519-1]; Swedish Foundation for Strategic Research (SSF)Swedish Foundation for Strategic Research [RIF 14-0074]

ScN-rich (Sc,Nb)N solid solution thin films have been studied, motivated by the promising thermoelectric properties of ScN-based materials. Cubic Sc1-xNbxN films for 0 amp;lt;= x amp;lt;= 0.25 were epitaxially grown by DC reactive magnetron sputtering on a c-plane sapphire substrate and oriented along the (111) orientation. The crystal structure, morphology, thermal conductivity, and thermoelectric and electrical properties were investigated. The ScN reference film exhibited a Seebeck coefficient of -45 mu V/K and a power factor of 6 x 10(-4) W/m K-2 at 750K. Estimated from room temperature Hall measurements, all samples exhibit a high carrier density of the order of 10(21) cm(-3). Inclusion of heavy transition metals into ScN enables the reduction in thermal conductivity by an increase in phonon scattering. The Nb inserted ScN thin films exhibited a thermal conductivity lower than the value of the ScN reference (10.5W m(-1) K-1) down to a minimum value of 2.2 Wm(-1) K-1. Insertion of Nb into ScN thus resulted in a reduction in thermal conductivity by a factor of similar to 5 due to the mass contrast in ScN, which increases the phonon scattering in the material. Published by AIP Publishing. ; Funding Agencies|European Research Council under the European Community [335383]; Swedish Foundation for Strategic Research (SSF) through the Future Research Leaders 5 program; Swedish Research Council (VR) [621-2012-4430, 2016-03365]; Knut and Alice Wallenberg Foundation through the Wallenberg Academy Fellows program; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; project NanoCaTe (FP7-NMP) [604647]; project CTEC [1305-00002B]

For applications in energy harvesting and environmentally friendly cooling, and for power sources in remote or portable applications, it is desired to enhance the efficiency of thermoelectric materials. One strategy consists of reducing the thermal conductivity while increasing or retaining the thermoelectric power factor. An approach to achieve this is doping to enhance the Seebeck coefficient and electrical conductivity, while simultaneously introducing defects in the materials to increase phonon scattering. Here, we use Mg ion implantation to induce defects in epitaxial ScN (111) films. The films were implanted with Mg+ ions with different concentration profiles along the thickness of the film, incorporating 0.35 to 2.2 at. % of Mg in ScN. Implantation at high temperature (600 degrees C), with few defects due to the temperature, does not substantially affect the thermal conductivity compared to a reference ScN. Samples implanted at room temperature, in contrast, exhibited a reduction of the thermal conductivity by a factor of 3. The sample doped with 2.2 at. % of Mg also showed an increased power factor after implantation. This paper thus shows the effect of ion-induced defects on thermal conductivity of ScN films. High-temperature implantation allows the defects to be annealed out during implantation, while the defects are retained for room-temperature implanted samples, allowing for a drastic reduction in thermal conductivity. ; Funding Agencies|European Research Council under the European Community [335383]; Swedish Foundation for Strategic Research through the Future Research Leaders 5 program; Swedish Research Council [2016-03365]; Knut and Alice Wallenberg Foundation through the Wallenberg Academy Fellows program; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (SFO-Mat-LiU Faculty Grant) [2009 00971]; DAE-BRNS [37(3)/14/02/2015/BRNS]