Charge pumping in monolayer graphene driven by a series of time-periodic potentials

We applied the Floquet scattering-matrix formalism to studying the electronic transport properties in a mesoscopic Dirac system. Using the method, we investigate theoretically quantum pumping driven by a series of time-periodic potentials in graphene monolayer both in the adiabatic and non-adiabatic regimes. Our numerical results demonstrate that adding harmonic modulated potentials can break the time reversal symmetry when no voltage bias is applied to the graphene monolayer. Thus, when the system is pumped with proper dynamic parameters, these scatterers can produce a nonzero dc pumped current. We also find that the transmission is anisotropic as the incident angle is changed.Comment: 8 pages, 6 figure

Optimisation of abrasive wear of rice husk reinforced epoxy composite by using response surface methodology

Wear is the disintegration or sideways uprooting of a material from its "derivative" and unique position on a solid surface performed by the movement of an alternate surface. The requirement for relative movement between two surfaces and mechanical contact between asperities is a paramount refinement between mechanical wear contrasted with different courses of action with comparative results. The wear analysis is possible by expository procedures like Response Surface Methodology. Response Surface Methodology (RSM) is an accumulation of statistical and mathematical techniques helpful for creating, enhancing, and upgrading methodologies. It additionally has important requisitions in the outline, advancement, and definition of new items, and also in the change of existing item plans. The broadest provisions of RSM are in the modern world, especially in circumstances where several input variables conceivably impact some performance measure or quality characteristic of the product or process

Development of a microprocessor-based biochemical sampler

Modern medicine requires patients to be treated on the basis of precise data, which are often obtained from electronic equipment. An inexpensive and portable microprocessor-based sampler developed by the authors is described. It is comprised of the following units: sample plate assembly, probe-drive linkage system, wash fluid receptacle, timing system and 8085A microprocessor

Development of a photometric system for continuous flow analysis

Most chemical analyses carried out in a clinical laboratory are colorimetric. An improved photometric system is described where a tungsten lamp is the light source, a photo-diode is the detector and a microcontroller 8051 is used for processing and displaying absorbances. The performance characteristics of the instrument are reported. The parameters investigated are photometric linearity, precision and instrumental drift

Effect of nano and macro iron sprays on growth, flowering, seed and oil yielding attributes in calendula (Calendula officinalis L.)

The investigation was executed with nine treatments viz. nano forms of ferrous sulfide (7, 14, 21, 28 ppm) and macro ferrous sulphate (0.2, 0.4, 0.6, 0.8 per cent) along with control, and were applied as foliar sprays after 30 days of transplanting on two varieties of calendula namely Fiesta Gitana Mix’ and ‘Fiesta Yellow’ during 2018 and 2019. The experiment was laid out in factorial randomized block design with three replications. Application of 0.8 % FeSO4 recorded maximum number of branches (26.75), plant height (29.73 cm), plant spread(45.17 cm), number of leaves (22.63) and seed test weight (15.63 g) and number of flowers per plant (134.04). However, application of 0.2% macro FeSO4 resulted in early bud appearance (50.50 days) and higher flower diameter (8.09 cm). ‘Fiesta Gitana Mix’ outperformed over ‘Fiesta Yellow’ for most of the vegetative and floral characters. The ‘Fiesta Yellow’ variety with oil content (13.97%) had an edge over ‘Fiesta Gitana Mix’

Reactive Extraction of Propionic Acid Using Aliquat-336 in 2-Octanol: Linear Solvation Energy Relationship (LSER) Modeling and Kinetics Study

Reactive extraction is an important recovery method for extraction of propionic acid from dilute streams, providing numerous advantages like high selectivity and recovery. Equilibrium and kinetic study of reactive extraction is essential to choose a proper extractant-diluent for acid recovery and ascertain the kinetic parameters essential for design of the process. In this paper, the linear solvation energy relationship (LSER) modeling of reactive extraction of propionic acid using Aliquat 336 in 2-octanol as diluent was presented to obtain the model parameters. Also, the kinetics of extraction in stirred cell was presented to explain the progress of reactive extraction of propionic acid using Aliquat 336 in the diluent. The reaction was found to be fast pseudo first order. To design the reactor to carry out reactive extraction, the kinetic parameters evaluated are essential. Modeling using LSER model predict a close resemblance of experimental data

Latitudinal trends in O<SUB>3</SUB>, CO, CH<SUB>4</SUB> and SF<SUB>6</SUB> over the Indian Ocean during the INDOEX IFP-1999 ship cruise

Surface measurements of ozone (O3), carbon monoxide (CO), methane (CH4) and sulfur hexafluoride (SF6) were made over the Arabian Sea and the Indian Ocean during the INDOEX field experiment in January- March 1999 covering the latitude range from 17&#176;N to 20&#176;S. Observations show decreasing trends in all these trace gases from the Indian coastal region to the open Indian Ocean. Ozone with a lifetime of few days, shortest among the species presented here, shows large variations while SF6, which has relatively longer lifetime, shows smaller variations. Ozone also shows clearly the effect of ITCZ and its movement. These observations show higher ozone near the Indian coastal region in January 1999 than in March 1999 and also compared to the observed ozone during the INDOEX-1998 cruise. This is believed to be due to strong anti-cyclonic conditions in January 1999 bringing more polluted air from the Indian continent. A decrease in the latitudinal gradient in CH4 was observed in 1999 compared to that in 1998 in the same region, indicating slower growth rate in 1998-1999 period

Prediction and management of natural disasters through indigenous Technical Knowledge, with special reference to fisheries

Traditional Indigenous knowledge has over the years played a significant role in solving several major social-ecological problems including those related to climate change and variability. People living close to nature often observe the circumstances around them and are the often the first to identify and adapt to any changes. The appearance of certain birds, mating of certain animals and flowering of certain plants are all seen as important signals of change with respect to timing and seasonality of natural phenomena that are well understood in traditional knowledge systems. Indigenous and local peoples have relied on biodiversity as a buffer against environmental variation, change and catastrophe