Green synthesis of silver nanoparticles using aqueous solution of Ficus benghalensis leaf extract and characterization of their antibacterial activity

The present study reports an environmentally friendly and rapid method for synthesis of silver nanoparticles. Although several articles have been reported for the synthesis of silver nanoparticles from plant extract, here we have developed a green synthetic method for silver nanoparticles using Ficus benghalensis leaf extract which acts as a reducing and capping agent. It was observed that use of Ficus benghalensis leaf extract makes a fast and convenient method for the synthesis of silver nanoparticles and can reduce silver ions into silver nanoparticles within 5 min of reaction time without using any harsh conditions. Silver nanoparticles so prepared were characterized by using UV-visible spectroscopy, transmission electron microscope-energy dispersive spectra (TEM-EDS) and X-ray diffraction (XRD). Further, these nanoparticles show effective antibacterial activity toward E.coli MTCC1302 due to high surface to volume ratio.     

Broadening of Photonic Band Gap in a One—Dimensional Superconductor Star Waveguide Structure

The present paper describes the theoretical investigation of enlarged reflection bands (photonic band gaps) in a 1D star waveguide (SWG) structure consists of superconductor and dielectric as its constituent materials. For the present study, we take the different combinations of superconductor and dielectric materials as a backbone and side branches of the SWG structure. In order to obtain the dispersion relation, Interface Response Theory (IRT) has been employed. Photonic band gaps of SWG structure having superconductor?Csuperconductor, superconductor?Cdielectric, and dielectric?Csuperconductor materials are compared with the band gaps of the conventional photonic crystal (PC) structure having superconductor?Csuperconductor and dielectric?Csuperconductor materials. Analysis of the dispersion characteristics shows that there exists no band gaps for conventional PC when both layers are made of the same superconducting materials (as the usual case) while the SWG structure shows forbidden bands of finite width even the backbone and side branches are made of same materials. Also, the SWG structure having superconductor?Cdielectric shows the wider reflection bands in comparison with the structure having dielectric?Csuperconductor as its constituent materials, while for the conventional PC structure it is same in both the cases. Further, the effect of temperature and the effect of variation of number of grafted branches on the photonic bands of SWG structure have been studied.     

SIFO–VM/TIM universal biquad filter using single DVCCTA with fully CMOS realization

Analog Integrated Circuits and Signal Processing - In the presented paper, a new biquad topology is reported and described wherein five various types of filtering responses in each voltage mode and...     

A New UTD Based Time-Domain Solution for UWB Diffraction in 3-D Environments

Wireless Personal Communications - In this paper, a new time-domain (TD) solution is proposed for analyzing the diffraction of ultra wideband (UWB) signals in three dimensional (3-D) scenarios. In...     

Effect of temporal pH variation of the reaction mixture on Mg(OH)2 morphology precipitated from an aqueous Mg(NO3)2-NaOH system

To understand the impact of temporal pH variation on the crystallisation process, Mg(OH)₂ was synthesized via wet precipitation route from an aqueous Mg(NO₃)₂-NaOH system. A detailed analysis of morphological evolution and the nano-structural transformation was carried out to model the crystallisation process. Interestingly, low supersaturation at low pH level lying between 9.2 and 9.4 of the reaction mixture, was found to promote the growth of nanorod like 1-D structures. On the contrary, enhanced supersaturation created a chemical driving force favouring an edgewise growth of the nucleated primary nanocrystals along (101) and (110) crystallographic planes, which resulted in lamellar hexagonal nanostructures. The lamellar growth demonstrated an increment in the particle size and reduction in anisotropic strain and dislocation density due to proper nucleation in the samples. Such controlled growth and nucleation of the Mg(OH)₂ morphology presents a great scope of potential applications of this material.     

Recovery and Characterization of Nickel Oxalate and Oxide Obtained from Spent Methanation Catalysts

Metallurgical and Materials Transactions B - In this paper, hydrometallurgical extraction and characterization of nickel from spent methanation catalyst composed of components NiO, Al2O3, Fe2O3,...     

Some experimental investigations in the WiMAX band and comparison of propagation models in mixed urban environments of Western India

This paper presents the analysis of measurements taken at 2.3?GHz in the mixed urban environments of Western India for 17 WiMAX base stations. Coverage predictions using various models and their comparison with observed data have been carried out. Measured path loss is compared with the theoretical path loss values estimated by COST-231 Hata model, the SUI model, the ECC model, and ITU-R (P.1411-1) model. This investigation is essential to provide last mile broadband wireless access, before deploying WiMAX. Path loss exponents, mean errors, and standard deviations of all the prediction methods were deduced and suitable models for path loss prediction methods were identified.     

A novel strategy for automatic test data generation using soft computing technique

Software testing is one of the most crucial and analytical aspect to assure that developed software meets prescribed quality standards. Software development process invests at least 50% of the total cost in software testing process. Optimum and efficacious test data design of software is an important and challenging activity due to the nonlinear structure of software. Moreover, test case type and scope determines the quality of test data. To address this issue, software testing tools should employ intelligence based soft computing techniques like particle swarm optimization (PSO) and genetic algorithm (GA) to generate smart and efficient test data automatically. This paper presents a hybrid PSO and GA based heuristic for automatic generation of test suites. In this paper, we described the design and implementation of the proposed strategy and evaluated our model by performing experiments with ten container classes from the Java standard library. We analyzed our algorithm statistically with test adequacy criterion as branch coverage. The performance adequacy criterion is taken as percentage coverage per unit time and percentage of faults detected by the generated test data. We have compared our work with the heuristic based upon GA, PSO, existing hybrid strategies based on GA and PSO and memetic algorithm. The results showed that the test case generation is efficient in our work.     

Influence of micropolar lubricants on the performance of slot-entry hybrid journal bearing

A theoretical study concerning the slot-entry hybrid journal bearing lubricated with micropolar lubricants is presented. The modified Reynolds equation for micropolar lubricant is solved using finite element method along with equation of lubricant flow through slot-entry restrictors as a constraint together with appropriate boundary conditions. It has been observed that a slot-entry hybrid journal bearing operating with micropolar lubricant shows an increase in the value of minimum fluid film thickness and a reduction in the value of coefficient of friction as compared to a corresponding similar slot-entry hybrid journal bearing operating with Newtonian lubricant.     

Iterative Dichotomiser Posteriori Method Based Service Attack Detection in Cloud Computing

Cloud computing (CC) is an advanced technology that provides access to predictive resources and data sharing. The cloud environment represents the right type regarding cloud usage model ownership, size, and rights to access. It introduces the scope and nature of cloud computing. In recent times, all processes are fed into the system for which consumer data and cache size are required. One of the most security issues in the cloud environment is Distributed Denial of Service (DDoS) attacks, responsible for cloud server overloading. This proposed system ID3 (Iterative Dichotomiser 3) Maximum Multifactor Dimensionality Posteriori Method (ID3-MMDP) is used to overcome the drawback and a relatively simple way to execute and for the detection of (DDoS) attack. First, the proposed ID3-MMDP method calls for the resources of the cloud platform and then implements the attack detection technology based on information entropy to detect DDoS attacks. Since because the entropy value can show the discrete or aggregated characteristics of the current data set, it can be used for the detection of abnormal data flow, User-uploaded data, ID3-MMDP system checks and read risk measurement and processing, bug rating file size changes, or file name changes and changes in the format design of the data size entropy value. Unique properties can be used whenever the program approaches any data error to detect abnormal data services. Finally, the experiment also verifies the DDoS attack detection capability algorithm.