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Sūrat, India

Shah R.,Uka Tarsadia University | Jha S.,Navsari Agricultural University
Chemistry and Ecology | Year: 2013

Twenty five different arsenite (AsIII) oxidising bacteria were isolated from industrial effluent (Bilimora, Gujarat Industrial Development Corporation (GIDC) Gujarat, India). The most efficient arsenite oxidiser and arsenite hyper-tolerant bacterial isolate which could tolerate up to 15 mM AsIII was selected and 16S rRNA gene sequence analysis was performed. It showed 98% identity of the 16S rRNA genes of genus Alishewanella (Accession no.: HQ659190). Higher activities of arsenite oxidase enzymes in the bacterium were localised on membrane. The GIDC-5 bacterial strain was found to be susceptible to most of the common antibiotics. The optimum growth in the presence of metalloid was observed at temperature 37°C and pH 4, whereas in the absence of metalloid the optimum pH was 8. The result suggested that, Alishewanella sp. strain GIDC-5 demonstrated hyper-tolerant to arsenite because of its ability to overcome the toxic effects of arsenite by converting it to less toxic forms (arsenate). © 2013 Copyright Taylor and Francis Group, LLC. Source

Mohammad F.,University Putra Malaysia | Mohammad F.,Southern University and A&M College | Arfin T.,Uka Tarsadia University
Advanced Materials Letters | Year: 2014

In continuation to our previous work, the superparamagnetic Fe3O4@Au core-shell type nanoparticles (NPs) were further characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), electrical conductivity, impedance and cyclic voltammetry measurements. From the analysis of DSC and TGA results with our Fe3O4@Au NPs of about 6.25 ± 0.6 nm size, we observed a clear endothermic peak at 310°C due to the decomposition of the oleic acid/oleylamine surface ligands and the particles found to contain more than 80% of the metallic content from the mixed compositions of gold and iron oxide. Because of the conduction through the Fe3O4@Au grain, the impedance profile of the pellet exhibited a well-resolved semi-circle and an inclined spike in a far low-frequency region. The electrical conductivity of the Fe3O4@Au material found to be increased with an increase of temperature. The standard Gibbs free energy (ΔG) of the reaction provided a criterion for spontaneous changes in the equilibrium of the material. From the analysis of the results of ΔG, it appears that at 25°C temperature, ΔS found to be negative. The calculated enthalpy, ΔH = -0.635 kJ/mol, at the corresponding entropy of ΔS = -0.132 kJ/mol. Finally, the activation energy in temperature range of 25-200°C for the Fe3O4@Au core-shell material was calculated using Line fitting and the surface characterization by using cyclic voltammetry. The electrochemical redox property of the Fe3O4@Au quasi-reversible wave corresponding to Au3+/Au2+. In addition, the electrochemical parameters for Fe3O4@Au NPs of (Ec p, (Ea p), (E0 1/2) and ΔE were also obtained. Since the Fe3O4@Au material has low activation energy at low temperature range which makes it a good candidate as an ion conductor and even has the potential uses in many solid state devices and also in the future prospects of electrochemistry applications. © 2014 VBRI press. Source

Sakhreliya S.C.,Uka Tarsadia University | Pandya N.H.,Parul Institutes of Engineering and Technology
2014 IEEE International Conference on Computational Intelligence and Computing Research, IEEE ICCIC 2014 | Year: 2014

Main use of VANETs is to provide safety by exchanging the warning messages between the vehicles so, it is time constraint. There is also requirement to resist various abuses and security attacks. An ECDSA algorithm used with PKI system to provide security but, it comes with the authentication overhead. TESLA uses MAC algorithm but, it is not feasible for delay-intolerant VANETs. Here PKI-SC system is proposed in that MAC algorithm can be used with classical PKI system using certificate scheme. To make comparison between PKI and PKI-SC system, ECDSA and MAC algorithms respectively are implemented on nodes and, to compare communication delay packet size of both system is used. For the analysis purpose formulas and processing time has been used to see, how different parameters effects on the authentication delay hence, on the braking distance of the vehicles. Results conclude that authentication time is very low for proposed system, which is near to the message without security so, it will solve issue of availability and braking distance is very low for proposed system. So, using the proposed system provides security, communication delay is also reduced and there is no issue of authentication overhead. It also provides multi-hop communication that is not possible in TESLA. © 2014 IEEE. Source

Mistry B.D.,Bkm Science College | Desai K.R.,Uka Tarsadia University | Desai N.J.,Bkm Science College
Der Pharma Chemica | Year: 2016

4-(2,5-Dichloro-3-Thienyl)-6-Aryl Pyrimidine-2-Amine 2a-m, 7-Chloro-N-[4-(2,5-dichloro-3-thienyl)-6-Aryl pyrimidine-2-yl] quinoline-4-amine 3a-m and 4-(2,5-dichloro thiophen-3-yl)-2-aryl benzo[1,4]thiazepine 4a-m have been synthesized from (2E)-3-aryl-1-(2,5-dichloro-3-thienyl)prop-2-en-1-one 1a-m by the cyclization with guanidine nitrate and then condensation with 4,7-dichloroquinoline(2a-m, 3a-m) and cyclization with o-amino thiophenol respectively (4a-m). Compounds (2E)-3-aryl-1-(2,5-dichloro-3-thienyl)prop-2-en-1-one 1a-m was synthesized from 1-(2,5-dichloro thiophen-3-yl)-ethanone and various aromatic aldehyde. The structures of novel synthesized compounds have been established on the basis of IR, 1 H NMR, 13 C NMR and Mass spectral data and screened for their antimicrobial activities against different microorganisms by micro dilution method. Isoniazid, Rifampicin, chloroquine, quinine, Gentamycin, Ampicilin, Chloramphenicol, Ciprofloxacin, Norfloxacin, Nystatin and Greseofulvin were used as standard drugs for mycobacteria H37Rv, malarial parasite P.falciparum, bacteria E.coli, P.aeruginosa, S.aureus, S.pyogenus and fungus C.albicans, A.niger, A.clavatus. Source

Vyas Z.M.,Uka Tarsadia University | Lineswala K.,Uka Tarsadia University | Pathak K.C.,Gujarat Technological University
IEEE International Conference on Computer Communication and Control, IC4 2015 | Year: 2015

In today's digital multimedia communication field different compression standards are evaluated for better visual and audio quality with low bitrates and storage space. The main goal of the standard is to providing unique display place for video applications. The Digital video standard H.264 /AVC aims at having significant improvements in coding efficiency and quality. H.264 is the standard that reduce irrelevant information and error without using extra bandwidth compared to previous standards such as MPEG-2, H.261, H.263. In digital world, due to challenges in different video applications there are many packet losses and damages are created because of transmission error or loss. So, in this paper to overcome related issues the algorithm was developed for post processing error concealment is weighted interpolation and another technique used that is Intra prediction which conceal damaged macroblocks using prediction modes. An experimental performance shows that weighted interpolation is create visible artifacts in edge region also, with degraded PSNR than proposed algorithm. Intra prediction has better objective quality than weighted Interpolation and EIPMS (Efficient Intra prediction mode selection) algorithm. © 2015 IEEE. Source

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