Dispersion of a solute in a Herschel–Bulkley fluid flowing in a conduit

The dispersion of a solute in a Herschel-Bulkley fluid is studied by using the generalized dispersion model in both pipe and channel. With this method the entire dispersion process is described as a simple diffusion process with the effective diffusion coefficient as a function of time. The results for Newtonian fluid, power law fluid and Bingham fluid are obtained as special cases by giving appropriate values to the power law index and yield stress. The effects of power law index, yield stress on the dispersion coefficient and mean concentration have been discussed computationally and graphically. The effect of power law index and yield stress is found to reduce the dispersion coefficient. It is observed that the critical time for dispersion coefficient to reach the steady state is varying with the yield stress and power law index. It is noticed that time to assume the critical value in Newtonian case is 0.5 and in the channel case the corresponding value of time is 0.55 which are in agreement with the existed results. It is also observed that in the non- Newtonian fluids this time is less than that of Newtonian fluid case and in Bingham fluid the critical value of time in pipe flow analysis (channel flow analysis) is attained at 0.45 (0.52) while in power law fluid it is at 0.43(0.48) and in the case of Herschel-Bulkley fluid it is 0.41 (0.45)

Development of eAgromet Prototype to Improve the Performance of Integrated Agromet Advisory Service

In several countries, the systems for forecasting weather are being operated to deal with weather and its related factors affecting agricultural production. India meteorological department (IMD) is providing several types of weather forecasts. One of the forecast service is medium range forecast (MRF). As a part of MRF, the expected values of rain fall, temperature, cloud cover, humidity, wind speed and wind direction for next five days are forecasted twice a week by considering district as a unit. Agriculture is markedly affected by weather condition during crop season. IMD in collaboration with Indian Council of Agriculture Research (ICAR) and State Agriculture Universities (SAUs) has set-up about 130 Agro-meteorological Field Units (AMFUs) and each AMFU covers about five districts. Based on MRF, IMD is rendering Integrated Agromet Advisory Service to the farming community of the country in the form of agromet advisory bulletin. The agromet advisory bulletins contain possible risk mitigation measures for the major crops and livestock. Based on the weather forecast, a group of interdisciplinary scientists and agromet scientists at AMFU prepare district-level agromet advisory bulletins. These bulletins are sent to the farmers and other stakeholders of the corresponding district. To ease the process of preparing agromet bulletins, an effort has started to build IT-based agrometeorological advisory system called, eAgromet. In this paper, we explain the concepts of eAgromet and its operation

Biomarkers as ecological indices in monitoring the status of market fish

Abstract Background Environmental contamination has become a major concern over the past few decades, drawing the attention of numerous researchers from both developed and developing nations. The aquatic system serves as the primary sink for the disposal of garbage, which has a negative impact on the aquatic environment and biota. The reality is that heavy metals cannot be totally removed from the ecosystem because they can bioaccumulate and grow in strength as they move up the food chain. Particularly heavy metals can build up in the tissues of aquatic animals, and as a result, tissue concentrations of heavy metals may be harmful to both human and animal health. Our study aimed to elucidate the possible use of biomarkers in monitoring and assessing the heavy metals contaminants among fresh water fish. Results From the present study, we conclude that glutathione peroxidase can be used as the bioindicator for nickel and iron contamination. Ultimately, these studies focus on measuring levels of pollution that may induce irreversible ecological changes to aquatic ecosystems. Till now the level of toxicity was moderate, and it was progressing toward the danger. Efforts can be made to control the activities that release pollutants unnaturally into the environment from both public and government so that the clean and clear environment can be maintained. Conclusions The work concludes that a multiparameter analysis is needed to assess and monitor the ecological status of the aquatic environment