Vignan University

About: Vignan University is a education organization based out in Guntur, Andhra Pradesh, India. It is known for research contribution in the topics: Computer science & Control theory. The organization has 1138 authors who have published 1381 publications receiving 7798 citations.

Optimization of Cu (II) biosorption onto sea urchin test using response surface methodology and artificial neural networks

Abstract: Copper biosorption potential of the biomass prepared from shells of sea urchin from aqueous solutions at optimum process conditions was studied. Response surface methodology and artificial neural network combined with central composite design were used for modeling and optimization of biosorption and to study interaction effects of process variables. A two-level three-factor face-centered central composite design was used for the experimental design. The influence of pH, initial copper concentration and biosorbent dosage on biosorption of copper was investigated. Prediction capacities of both models were compared and found that response surface methodology showed better prediction performance than artificial neural networks. Kinetic data were well fitted to second-order rate equation showing maximum biosorption capacity of 15.625 mg/g for 100 mg/l metal solution concentration. It was further confirmed by fitting the data to Elovich model. Biosorption mechanism was investigated using intra-particle diffusion and Boyd models. The optimum copper removal efficiency of the biosorbent was found as 89.09%.

Nutraceuticals derived from seed storage proteins: Implications for health wellness

Abstract: Seed storage proteins are major source of proteins because of readily available bioactive peptides. These peptides are fragments of a protein, which showed positive implications on human wellness and gained wide importance owing to their health benefits such as antimicrobial, antiviral, antifungal, anti-tumor activities. In plants, the bioactive peptides are ubiquitous in distribution that act as a part of innate response upon elicitation. In addition, these plant based bioactive peptides have structural similarity with the insect and animal sources. In most of the cases, the bioactive peptides triggers their response by binding the target membrane that results into permeabilization and rupture of the membrane. Delineating the potential of peptides having antiviral, antimicrobial and antiviral properties these can be used in the food and pharmaceutical industries. Further, these peptides can be used into the packaging material called active packaging that enhances the shelf life and quality of the food. In this review, seed storage proteins based bioactive peptides and their potent applications for health as well as food industry have been elucidated.

Generation expansion planning based on solar plants with storage

Abstract: The introduction of renewable energy technologies (RET), like solar and wind power plants, into a power system introduces both expansion and operational challenges. Earlier studies have indicated the requirements for additional backup power facilities requirements for every addition of RET plants, due to the unique generation characteristics of these RET plants. Of late, alternative strategies of creating power storage facilities using power from RETs and drawing constant supply from such storage facilities are drawing the attention of power system planners. In this paper, generation expansion planning (GEP) mathematical modeling studies are carried for a candidate power system, to study the impact of introduction of solar power plant with storage facility. The study is planned in a four-level hierarchy, based on (a) investment strategies of introducing solar plants as an alternative candidate plant or as a replacement of existing high emission plants (HEP) (b) whether the solar plant with storage (SPWS) or with no storage (SPWNS) capacity and (c) inclusion of treatment/penalty costs on emissions from high emission plants. The sensitivity of the system performance factors, like, the capacity added, overall costs and EENS for variations in assumed Forced outage rate (FOR%) for SPWNS and SPWS is also carried for assumed solar penetration levels of 5–10% and 10–20% for 6-year and 14-year planning horizons. The system performance was highly sensitive to the assumed FOR%. The model investigations offer an encouraging scenario in power system planning when SPWS is introduced as an alternative investment candidate plants into the system. This study, while attempting to illustrate the complexity of decision making process in introducing solar plants into an existing system provides a four-level hierarchy in understanding comprehensive set of policy issues that might arise in GEP and enables planners to adopt situation-specific solutions.

Dry sliding wear behavior of Al 6082 metal matrix composites reinforced with red mud particles

Abstract: The present study aims at investigating the dry sliding wear behavior of Al-based 6082 metal matrix composites (AMMCs) reinforced with red mud particles by pin-on-disc configuration. AMMCs were fabricated with three different weight fractions of red mud particles ranging from 2 to 6% by using the stir-casting method. The friction coefficients and volumetric wear rates were continuously evaluated under normal loads of 10–30 N and sliding speed of 1.5 m s−1 for the constant sliding distance of 1000 m. Microstructural analysis indicated that red mud particles are more or less uniformly dispersed throughout the Al matrix with minimal agglomeration. Experimental data shows that microhardness and tensile strengths of both the as-cast and heat-treated composites are steadily improved by increasing the amount of reinforced red mud particles but at the cost of ductility. Analysis of worn surfaces revealed that delamination and abrasion are dominant wear mechanisms for the case of the heat-treated composites are whereas the adhesion wear mechanism for the base alloy. The composite containing 4% red mud particles experienced the lowest wear rate at a normal load of 30 N and sliding speed of 1.5 m s−1 as compared to other composites including the base alloy. While the composite with 2% red mud particles shows the lowest friction coefficient, base alloy exhibited the highest friction coefficient.