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: Control theory & CMOS. The organization has 1138 authors who have published 1381 publications receiving 7798 citations.

Temperature-Stable Compelled Composite Superhydrophobic Porous Coordination Polymers Achieved via an Unattainable de Novo Synthetic Method

Abstract: We demonstrate a new de novo synthetic methodology to achieve high-temperature-stable compelled composite superhydrophobic porous coordination polymers (PCPs). These new PCPs were achieved based on coordination capabilities of first-row transition metal ions such as Co2+, Ni2+, and Zn2+. The obtained composite PCPs containing a [Zn2M2O]6+ (M = Co or Ni) bimetallic cluster core with open metal sites (OMSs) exhibited distinct isosteric heats of adsorption and surface areas due to the difference in their open metal Lewis acidic sites of solvent-free state. Additionally, these composite PCPs exhibit remarkable superhydrophobic properties with contact angles of 159.3° and 160.8° respectively for Zn–Co and Zn–Ni analogues. This superhydrophobic surface survives even at high temperature for longer time periods. As projected, these new composite PCPs exhibit better surface area and heats of adsorption compared to the PESD-1 (Zn) analogue due to a larger number of OMSs. Moreover, they display selective adsorption ...

Role and Regulation of Osmolytes and ABA Interaction in Salt and Drought Stress Tolerance

Abstract: Abiotic stress conditions lead to the defects in plant growth and development and also reduction in flowering and fertility. Under prolonged stresses, imminent death of the plants has been observed. To cope with such stress conditions, plants accumulate a wide variety of organic solutes called osmolytes. Osmolytes are accumulated in bacteria, lower, and higher plants as a response primarily to abiotic stress. They encompass amino acids such as proline, tertiary sulfonium, and quaternary ammonium compounds like beatines, sugars (trehalose), and polyhydric alcohols (mannitol, sorbitol, pinitol, etc.). Osmolytes are accumulated in the cytoplasm as well as in chloroplasts in certain cases for osmotic adjustment under stress conditions. This enables the plants to absorb water and survive under stress. Out of the many phytohormones that play diverse roles during abiotic stress, abscisic acid (ABA) is an important one and perceived by plants by a core signaling module. As an integral part of signal transduction during stress conditions, ABA and other hormones regulate not only stomatal closure, but also a wide array of gene expressions including osmolyte biosynthetic pathway genes. Many signal molecules like nitric oxide, carbon monoxide, and hydrogen sulfide also play a vital role in osmolyte biosynthesis. Osmolytes appear to have multiple functions during stress such as osmotic adjustment and scavenging of reactive oxygen species (ROS). Thus, generation of ROS and osmolyte accumulation are linked together. This review summarizes the role played by ABA in signal transduction, the role of hormones to regulate osmolyte biosynthesis, and various functions carried out by them.

Optimal allocation of distributed generations using hybrid technique with fuzzy logic controller radial distribution system

Abstract: In this concept, an enhanced idea is proposed for solving the optimal load flow issues with uncertainties. In this article the Fuzzy Logic Controller (FLC) technique and Ant-Lion Optimization Algorithm’s (ALOA) with Particle Swarm Optimization (PSO) based combination is proposed. The ALO imitates the hunting mechanism of ant lions in nature and the PSO improves the ALO performance by updating elitism phase of ALO. The FLC is trained based on training dataset and testing time which produces the optimal allocation parameters are based on the variation of radial distribution network parameters. In this projected hybrid algorithm, Photo-Voltaic and Wind Turbine generations (PV and WT) are considering as Distributed Generators (DGs). Initially, after defining the multi objective function, then about voltage deviation, minimization of power loss and improvement of voltage stability index is discussed. The minimization of cost of operation and deviation of voltage indexes are considered as multi objective functions and the projected technique is evaluate on IEEE 33 standard radial distribution systems. With new hybrid technique, allocation of multi-DGs like wind and PV at different sites, and the optimal load flow at various cases is analyzed.

A Novel Square Wave Generator Using Second-Generation Differential Current Conveyor

Abstract: By using two resistors and a single capacitor with second-generation differential current conveyor as an active element, a new square wave generator is proposed and implemented. The frequency of operation of the introduced model is varied with respect to the variation of remaining passive components. Maximum reduction in noise effects caused by parasitics generated during integrated circuit fabrication is achieved with the scheme of grounded capacitor. The mathematical model of the selected circuit is verified in both simulation and experimental mode and found having matched in all three aspects. The elevated advantages and merits of the given topology are compared and tabulated contrary to the existing standard models. Using Cadence virtuoso with gpdk 180 nm libraries, the circuit is verified with a supply rail voltage of ±2.5 V. Later, prototype is also tested with commercially available current feedback operational amplifiers of AD844AN.