Biological treatment of azo dyes on effluent by Neurospora sp isolated and adopted from dye contaminated site

Abstract

Application of fungal agents to develop eco-friendly and cost-effective dye removal from textile effluent was studied. A fungal strain Neurospora sp has been isolated from effluent site and tested for its ability to biosorption and biodegrade azodyes. Biosorption of azo dyes by live and dead fungal biomass was evaluated. Percentage of decolorization was found to be effective against all tested azodyes and ranges between 33 and 76%. Nearly 72% of azo dyes were removed by dead Neurospora sp biomass and 86% respectively by live active biomass. Biodegradation of textile effluent by Neurospora sp showed changes in BOD, COD and TOC indicates that isolated Neurospora sp effectively degrade and utilize the dye as a sole carbon source. The initial TOC of 2600?mg/L was approximately reduced to almost its three fourth within a week. Research works on application of fungal biomass on textile effluent treatment have proven decolorizing potential among a wide range of anionic and cationic dyes. Based on the results, the biosorption mechanism by Neurospora sp was observed as effective, economic and eco-friendly decontaminant.     

Floquet instability of a gravity modulated Rayleigh–Benard problem in an anisotropic porous medium

This work deals with the effect of gravity modulation on the onset of convection in a horizontal porous layer subjected to an adverse temperature gradient. Low amplitude gravity modulations are considered. The analysis is linear and specific attention is paid to the boundary effects of Brinkman's model and anisotropies of the porous medium in permeability and thermal conductivity. A Floquet analysis is applied and critical values of the parameters are found analytically using stability charts. The emergence of instability through the synchronous and subharmonic modes, transition between them and their dependence discussed for physically realistic values of control parameters. The findings of this analysis may be useful in controlling convective plumes during fabrication which develop into freckles in the ground grown crystals.     

Regulation of Charge Carrier Dynamics in ZnO Microarchitecture‐Based UV/Visible Photodetector via Photonic‐Strain Induced Effects

A feasible, morphological influence on photoresponse behavior of ZnO microarchitectures such as microwire (MW), coral‐like microstrip (CMS), fibril‐like clustered microwire (F‐MW) grown by one‐step carrier gas/metal catalyst “free” vapor transport technique is reported. Among them, ZnO F‐MW exhibits higher photocurrent (I_Ph) response, i.e., I_{Ph/ZnO F‐MW} > I_{Ph/ZnO CMS} > I_{Ph/ZnO MW}. The unique structural alignment of ZnO F‐MW has enhanced the I_Ph from 14.2 to 186, 221, 290 µA upon various light intensities such as 0 to 6, 11, 17 mW cm^?2 at λ_{405 nm}. Herein, the nature of the as‐fabricated ZnO photodetector (PD) is also demonstrated modulated by tuning the inner crystals piezoelectric potential through the piezo‐phototronic effect. The I_Ph response of PD decreases monotonically by introducing compressive strain along the length of the device, which is due to the synergistic effect between the induced piezoelectric polarization and photogenerated charge carriers across the metal–semiconductor interface. The current behavior observed at the two interfaces acting as the source (S) and drain (D) is carefully investigated by analyzing the Schottky barrier heights (Φ_SB). This work can pave the way for the development of geometrically modified strain induced performances of PD to promote next generation self‐powered optoelectronic integrated devices and switches.     

Lightweight and Secure Mutual Authentication Scheme for IoT Devices Using CoAP Protocol

Internet of things enables every real world objects to be seamlessly integrated with traditional internet. Heterogeneous objects of real world are enhanced with capability to communicate, computing capabilities and standards to interoperate with existing network and these entities are resource constrained and vulnerable to various security attacks. Huge number of research works are being carried out to analyze various possible attacks and to propose standards for securing communication between devices in internet of things (IoT). In this article, a robust and lightweight authentication scheme for mutual authentication between client and server using constrained application protocol is proposed. Internet of things enables devices with different characteristics and capabilities to be integrated with internet. These heterogeneous devices should interoperate with each other to accumulate, process and transmit data for facilitating smart services. The growth of IoT applications leads to the rapid growth of IoT devices incorporated to the global network and network traffic over the traditional network. This scheme greatly reduces the authentication overhead between the devices by reducing the packet size of messages, number of messages transmitted and processing overhead on communicating devices. Efficiency of this authentication scheme against attacks such as DoS (denial of service), replay attacks and attacks to exhaust the resources are also examined. Message transmission time reduced upto 50% of using proposed techniques.     

Hierarchical Tree Structure Based Clustering Schemes for Secure Group Communication

In recent years, many network applications are developed based on group communications (GC), in which the security has to be provided in terms of confidentiality, authenticity and integrity of messages delivered between the group members. A Hierarchical tree structure has to be constructed in such a way that it can handle large dynamic groups with the effective key formation and key distribution. In this paper, an Optimal Cluster Hierarchical Tree (OCHT) structure is presented for effective group communication. The proposed OCHT structure provides a novel solution for multicast key management with decentralized architecture to ensure scalability, reliability and cost effectiveness. Simulation results reveal that proposed OCHT based decentralized architectures provide better performance when compared with existing Logical Hierarchical Tree (LKH). The parameters used for simulation are Memory Overhead, Throughput, Packet Delivery Ratio, End-to-End Latency and Energy consumption.     

A highly reliable contact-separation based triboelectric nanogenerator for scavenging bio-mechanical energy and self-powered electronics

Journal of Mechanical Science and Technology - The increasing interest in harvesting mechanical energy from day-to-day activities is gaining huge interest among researchers. We have fabricated a...     

Investigation of natural convection heat transfer performance of the QFN-PCB electronic module by using nanofluid for power electronics cooling applications

Natural convection heat transfer of Cu-water nanofluid in a 3?×?3 array of a typical isothermal quad flat non-lead (QFN) embedded printed circuit board (PCB) module which can be bounded with respect to the sealed non-Darcy porous enclosure is numerically investigated. The Darcy-Brinkman-Forchheimer model is adopted to model the fluid flow in the porous medium under the presence of an external magnetic field. The transport governing equations are solved by the finite volume method based on the SIMPLE algorithm and the power law scheme. Main efforts focus on the effects of the parameters such as a nanoparticle volume fraction, Hartmann number, Darcy number and the enclosure side aspect ratio on the fluid flow and heat transfer characteristics inside the enclosure. The obtained results indicate that the influence of nanofluid of the overall Nusselt number increases with increasing the Darcy number, but decreases with increasing the Hartmann number. The overall Nusselt number attains its maximum value in the range of enclosure side aspect ratio from 1.5 to 3 with respect to the Darcy number. Moreover, the proposed correlations improve the efficiency, reliability and stability of the electronic device encountered in various applications in electronic industries.     

Computational fluid dynamics analysis of greenhouse solar dryer

Innovative technologies are needed to make the life easy. The innovations are best used using renewable source of energy. Greenhouse solar dryer is a device used for drying purpose. Computational fluid dynamics analysis simulation is performed on greenhouse solar dryer when exposed to an ambient temperature on a hot sunny day for free convection and forced convection processes. The mass flow rate and the thickness of polycarbonate roof sheet material vary. The average temperature of the dryer is analysed using simulation. The maximum temperature obtained by forced convection is 71°C for 0.025?kg/s mass flow rate, which is 41% more than that obtained by natural convection.