International Journal of Nanoparticles (20 papers in press)
Phytofabrication, Characterization and Antimicrobial Studies of Gold Nanoparticles Using Cannabis sativa (Bhang), Leaf Extract
by Neeraj Sharma, SHAILENDRA PRATAP SINGH
Abstract: Phytofabrication of gold nanoparticles by plant extract of cannabis sativa is at present under exploitation for the reason that to develop environmentally benign nanoparticles synthesis to avoid adverse effects in biomedical applications. Different concentrations of ethanolic leaf extract of the plant were reacted with aqueous solution of HAuCl44H2O. A fixed ratio of plant extract and metal ion was mixed which in turn showed the change in colour of the solution leading to the inference that nanoparticles are formed. Thecharacterization of nanoparticles was done by UV-vis Spectrophotometer, FTIR, and TEM. The particles synthesized were of the size ranging from 20-100 nm. The solution showed a peak at 560 nm on UV-VIS spectrum corresponding to the surface Plasmon resonance of gold nanoparticles. The shape of the nanoparticles was spherical according to Transmission electron microscopy.In these studies, the antimicrobial studies of the AuNPS were exploited against different micro-organisms. The results of UV-VIS,FT-IR and TEM confirm that the leaves extract of Cannabis sativa can be used to produce gold nanoparticles with significant amount of antimicrobial activity.
Keywords: Gold Nanoparticles; Leaf Extract; Anti-Oxidant; Cannabis sativa; TEM; FTIR; UV –VIS.
Caesalpinia pulcherrima mediated green synthesis of silver nanoparticles: Evaluation of their antimicrobial and catalytic activity
by Amol Dudhane, Samadhan Waghmode, Manohar Bhosale, Vaibhav Mhaindarkar
Abstract: Plant extracts are an efficient, eco-friendly and cost-effective alternative source for the synthesis of nanoparticles. In this study, silver nanoparticles (Ag NPs) were synthesized by treating the Caesalpinia pulcherrima (C.pulcherrima) leaf extract with aqueous silver nitrate solution at room temperature. The biosynthesized Ag NPs were characterized by techniques like transmission electron microscopy (TEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX) and ultraviolet-visible spectroscopy (UV-Vis). The TEM analysis reveals the formation of spherical Ag NPs with a diameter range of 30-50 nm. The in vitro antimicrobial activity of the synthesized Ag NPs was investigated against common human pathogens such as Pseudomonas aeruginosa (NCIM 5029), Serratiamarcescens (NCIM 2078), Staphylococcus aureus (NCIM 5021) and Salmonella typhimurium (NCIM 2501) by agar well diffusion method. The synthesized Ag NPs showed potential antimicrobial activity against all of the mentioned bacterial strains indicating its prospective use in the development of value-added products in the biomedical and nanotechnology-based industries. Furthermore, we have shown the catalytic degradation of methylene blue dye and reduction of p-nitroaniline using synthesized Ag NPs. Synthesised nanoparticles have shown excellent catalytic activity within a very short time period.
Keywords: Caesalpinia pulcherrima; silver nanoparticles; antimicrobial activity; catalytic reduction; green synthesis.
Plant mediated greener approach for synthesis of Silver Nano particles from Digitalis purpurea plant and its antibacterial activity
by Vishnuvarthanan M, Rajeswari N
Abstract: In this paper, the silver nanoparticles were biosynthesized using aqueous Digitalis purpurea leaf extract.. The biosynthesized silver nanoparticles were characterized by UV-visible spectrophotometer (UV-Vis), Fourier transform infrared spectroscopy (FTIR), X-ray diffractometer (XRD), Field emission scanning electron microscopy (FESEM), Energy Dispersive X-ray analysis (EDX) and High-resolution transmission electron microscopy (HRTEM). In the colloidal solution, the formation and stability of the silver nanoparticles were absorbed by UV-Visible and it showed the maximum absorption at 452 nm.The XRD and the HRTEM demonstrated that the silver nanoparticles were cubic structure, face centered with a particle size of 25 nm and the EDX showed the presence of silver element. The FTIR analysis showed the existence of various functional groups. The antibacterial activity of the synthesized silver nanoparticles had evaluated against the gram-negative Escherichia coli (MTCC 1652), gram-positive Staphylococcus aureus (MTCC 316) and it showed the efficient activity against the both gram-negative and gram-positive microorganisms.
Keywords: Green synthesis; Digitalis purpurea; AgNPs; FESEM;XRD; HRTEM; antibacterial activity.
Slip flow and nonlinear radiative heat transfer of suspended nanoparticles due to a rotating disk in the presence of convective boundary condition
by Prasannakumara B.C, Gireesha B.J, Krishnamurthy M.R, Rama Subba Reddy Gorla
Abstract: The slip flow and nonlinear radiative heat transfer of suspended nanoparticles due to a rotating disk is analyzed in the present work.Two types of nanoparticles namely Copper and Aluminum Oxide and water is treated as base fluid. Suitable similarity transformations are used to reduce the nonlinear partial differential equations to ordinary differential equations. Flow and heat transfer characteristics are computed by numerical technique Runge-Kutta-Fehlberg-fourth and fifth order method. Further, the skin friction coefficient and Nusselt number are presented and examined for pertinent parameters. It is noticed that the higher velocity slip parameter decreases the radial and azimuthal velocities. Also the rate of heat transfer enhances when the nanoparticle volume fraction increases.
Keywords: Nonlinear radiation; velocity slip; convective condition; nanoparticles; rotating disk.
Physical properties of nanosized cobalt doped TiO2 lms grown by pulsed laser deposition
by Faouzi Hanini, Abderrahmane Bouabellou, Yassine Bouachiba, Fouad Kermiche, Adel Taabouche, Kamel Boukheddaden
Abstract: Ti1-xCoxO2 (x =0-0.06) films were deposited at 450
Keywords: Co-doped TiO2; PLD; Anatase; Rutile; Nanoparticles; Waveguiding properties.
Aligned magnetic dipole in nonlinear radiative Falkner-Skan flow of Casson fluid over a wedge containing suspension of nanoparticles and microorganisms
by K.R. Sekhar, V. Reddy, C.S.K. Raju, B. Pullepu, R. Kumar, Sabir Shehzad
Abstract: This paper scrutinizes the influences of aligned magnetic field and nonlinearly radiative flow of Falkner-Skan Casson liquid towards a wedge which is filled with microorganisms and nanoparticles. Following Buongiorno’s model, the expressions of flow are developed and then transformed into self-similar form by utilizing appropriate similarity transformations. Numerical outcomes are presented through plots and tabular form by enforcing Newton’s and Runge-Kutta techniques. The impacts of arising constraints on liquid velocity, temperature, density of motile organisms and concentration are explored. For industrial and engineering interest, surface drag coefficient, rates of mass and heat transport, motile microorganism’s density number are investigated. A comparative analysis for two cases namely aligned magnetic field (AMF) and magnetic field (MF) demonstrates that rate of heat and mass transfer are high in AMF case in comparison to MF case, and therefore desired results can be obtained by utilizing AMF case.
Keywords: Casson fluid; Falkner-Skan flow; nanoparticles
INVESTIGATIONS ON EMISSION OF NANOPARTICULATES UNDER FREE ACCELERATION TEST CONDITION
by Venkataraghavan Nagarajan, Thirumalini Subramaniam
Abstract: Considering the dangerous effects of ultrafine particles and air quality concerns worldwide, this work investigates the possibility of identifying operating criterion over which there is a greater tendency of formation of nanoparticle emissions in Diesel engines. The objective of this analysis is to study the emission of particles in the size range of 10nm to 700nm by subjecting a diesel engine to free acceleration tests.
Details on the emission characteristics such as Particulate number, Particle mass, Particle diameter and the Lung deposition surface area in the size range 10-700nm during specific conditions of acceleration and deceleration has been studied in this work. Maximum effect of the particles occurs during rapid acceleration. At idle speed, the Particle number, particle mass and Lung deposition surface area are very low indicating that the nano particle formation is low at idle condition. With increase in Particulate number, there is an increase in the Particulate mass and the LDSA. The particulate diameter is distributed across the PN range.
Keywords: Nano-Particulate emission measurement, Diesel Engine, Free acceleration test
MHD Natural convective Ag-Water nanofluid flow in an enclosure having internal heat generation with center heater and bottom heat source
by Thangavelu Mahalakshmi
Abstract: A numerical study on MHD natural convection heat transfer of internal heat generating Ag-water nano fluid in the enclosure with an inside heater has been conducted. Two opposite vertical walls of the enclosure are maintained at temperature Tc whereas its top wall is insulated and bottom wall is considered with a constant heat source. The center heater with the temperature of Th (Th > Tc) is located in horizontal and vertical positions inside the enclosure which its length is varying. The governing equations are solved numerically by using finite volume method and SIMPLE algorithm. The effect of pertinent parameters such as length of heater, Rayleigh number, Hartmann number, heat generation parameter and volume fraction of nano particles are investigated. Results are presented in the form of streamlines and isotherm plots, variation of average Nusselt number and mid height velocity profile. It is observed from the results that high heat transfer is obtained for the vertical heater compared with horizontal heater and it is found that Hartmann number is a good control parameter for suppressing heat transfer. Moreover, the fluid flow, thermal fields and rate of heat transfer are strongly dependent on length of heater and heat generation parameter. Also it is found that increasing solid volume fraction of nano particles cause better enhancement of heat transfer inside the enclosure.
Keywords: Magnetic field, Nanofluid, Internal heat generation, Length of heater, Heat source.
Synthesis of silver nanoparticles using Green sources and comparative analysis.
by Nabodita Sinha, Tamalika Chakroborty, Abhijit Sengupta
Abstract: The various side effects of the chemical drugs and their incapability to fight with the increasing drug resistance has led to the research for new antimicrobials which would be able to fight with fast evolving microbial army in a cost effective and efficient manner. The most promising source for this up to date is probably the nanoparticles among which the silver nanoparticles have the best potential till date.. Silver has been used since time immemorial to treat cuts and burns and to treat wastewater but the effect of silver on human body in large dose may be toxic. The aim of this project is to identify the different types of sources from which the silver nanoparticles can be synthesized efficiently. Their comparative analysis has been done to compare their efficiency against Gram positive and Gram negative bacteria in the hope that further research would enlighten their uses more and a day may come when they would become our strongest fighter against microbial troops..
Keywords: Antimicrobial activity, Comparative analysis , Green sources. Silver nanoparticles.
Biosynthesis of silver nanoparticles using unriped Carica papaya fruit extract with different PH conditions
by Hooi Chien Ng, Cheng Seong Khe, Azizan Aziz, Zulkifli Merican Aljunid Merican, Rajalingam Sokkalingam, Thiam Leng Chew, Chin Wei Lai
Abstract: Silver nanoparticles were successfully synthesised at room temperature from silver nitrate using unripe Carica papaya fruit extract as a reducing and capping agent. PH of the reaction solution was adjusted with the addition of sodium hydroxide from pH 5.6 (original pH of the broth) to pH 6.5, pH 7.5 and pH 8.5. Quasi spherical silver nanoparticles were obtained across the studied pH range. The average particle size obtained decreased from 34 nm to 15 nm as the pH of the solution increased from 5.6 to 8.5. From the observations and ultra violet-visible spectrophotometer analysis, the rate of reduction and formation of silver nanoparticles increased as the pH increased. The crystalline nature of the as-synthesised silver nanoparticles in a cubic structure was confirmed by the peaks in X-ray diffraction and selected area electron diffraction. From Fourier transform infrared spectra, it was found that proteins in unripe papaya fruit extract were strongly bounded to the surface of silver nanoparticles as a capping agent. The thin layer of protein coating also further confirmed under high resolution transmission electron microscope. A plausible formation mechanism has been briefly proposed.
Keywords: biosynthesis; silver nanoparticles; Carica papaya fruit extract; pH; twinning.
Microalgae harvesting of Nannochloropsis sp. using polyethersulphone/lithium chloride/functionalised multiwall carbon nanotube membranes fabricated via temperature induced phase inversion and non-solvent induced phase inversion
by Nur Farahah Mohd Khairuddin, Ani Idris, Muhammad Irfan, Teo Chee Loong
Abstract: Microalgae are a promising renewable source especially for producing biofuels and other high value products. Biofuel and biomass production involves several steps from cultivation, harvesting and extraction. Recent technology has used ultrafiltration membrane for microalgae harvesting but are faced with adverse effect of microalgae fouling. In the present study, Nannochloropsis sp. harvesting was performed using an ultrafiltration hybrid membrane made of polyethersulphone (PES) blended with the two additives namely lithium chloride (LiCl) and functionalised multiwall carbon nanotube (F-MWCNT). The membranes were prepared via two methods; non-solvent induced phase separation (NIPS) and temperature induced phase separation (TIPS). The membrane performances were evaluated in terms of membrane flux and fouling for the use of microalgae harvesting. The FESEM analysis showed that the morphology of the hybrid PES-MWCNT-LiCl membranes was very much influenced by the phase separation method. Flux rates of the membranes improved dramatically with increasing amount of additives when prepared using TIPS. A 100% microalgae separation from cultivated solution without major fouling (more than 80% flux recovery) was successfully achieved.
Keywords: membrane; multiwall carbon nanotube; lithium chloride; nannochloropsis sp.
Structural transformation of polymeric and cationic capped zirconia nanoparticles with temperature
by Sreedevi R. Mohan, A. Uma Maheswari, M. Sivakumar
Abstract: The phase transformation mechanisms of zirconia nanocrystals obtained on thermal treatment of polyvinylpyrrolidone (PVP) and cetyltrimethylammoniumbromide (CTAB) capped hydrous amorphous zirconia (HAZ) on thermal treatment are investigated. In PVP assisted synthesis, tetragonal zirconia nanoparticles formation is the predominant one as compared to CTAB assisted synthesis. The decomposition of surfactants capped on HAZ with temperature (526°C for PVP and 466°C for CTAB) and subsequent interaction of the by-products with zirconia nanoparticles are responsible for tetragonal to monoclinic phase transformation. The decomposition temperature of capped surfactants is observed from thermogravimetric analysis (TGA) and subsequent interaction of by-products with zirconia nanoparticles at different temperatures is investigated from FTIR spectra. Further the structure of nanoparticles annealed at different temperatures is investigated using XRD, micro Raman and photoluminescence (PL) analysis.
Keywords: zirconia nanoparticles; phase transformation; annealing; surfactant; mineraliser.
Production of nano structure iron powder from blue dust
by Kamlesh Kumar
Abstract: One of the great triumphs in the field of nano materials and metal by nano technology is the success in developing of nano sized iron powder from iron ore concentrate (blue dust). NMDC has taken an initiative to utilise high-grade blue dust to produce value added product, i.e., nano structure iron powder (NSIP), which can fetch high value. After the up gradation of blue dust by physical method, the samples were leached by acid to produce value added product from blue dust. This was followed by leaching, precipitation, drying, reduction, grinding in argon atmosphere and characterised by SEM, XRD etc to confirm its nano character. This value added product having less than 100 nanometres size has its applications in computer engineering, electronics, instrument making, medicine, catalysis etc. Component made from nano structured materials have attracted large attention due to their high strength, excellent functional properties, better corrosion resistance, reduced sintering temperatures, etc. Paper contains preparation of nano sized particles (less than 100 nanometres) is connected to influence the dimensional effect on their physical, chemical, mechanical and other properties.
Keywords: blue dust; leaching; precipitation; minerals; drying; high strength; sodium hydroxide.
Structural and electrical studies of Mn-Ni mixed nanoferrites
by Elangbam Chitra Devi, Ibetombi Soibam
Abstract: Mn-Ni mixed spinel nanoferrites with varying nickel concentration (0.1, 0.2, 0.3, 0.4, and 0.5) were prepared by co-precipitation method. The spinel phase formation was confirmed by XRD and FTIR. Microstructure and compositional analysis were done by SEM and EDX respectively. Room temperature dielectric properties, resistivity and AC-conductivity were studied. The nanoferrites possess a very high dielectric constant. Dielectric loss tangent decreases with increase in nickel concentration and a broad peak appears for higher nickel concentration (0.2, 0.3, 0.4 and 0.5). Variation in DC-resistivity with nickel concentration goes in agreement with the variation of dielectric constant. Frequency variation of AC-conductivity for different nickel concentration shows dispersion at higher frequencies for different Ni concentration. Conduction mechanism has been explained on the basis of hopping electron model of ferrites.
Keywords: spinel ferrites; nanoparticles; X-ray diffraction; XRD; Fourier transform infrared spectroscopy; FTIR; electrical properties.
Greener synthesis of silver nanoparticle from Chordia dichotoma leaf extract and its antimicrobial activity
by P. Kalainila, R.S. Ernest Ravindran, V. Hemachandran, S. Renganathan
Abstract: Greener synthesis of silver nanoparticles (AgNPs) using the leaf extract of Chordia dichotoma. After the addition of leaf extract into the silver nitrate solution the colour change was observed that clearly confirms the formation of AgNPs. The synthesised AgNPs undergo the surface plasmon resonance (SPR) effect for the size reductions were confirmed by the formation of peak at 431 nm from UV-visible spectroscopy (UV-Vis). The stability of the nanoparticles were studied at different time interval (0 to 72 h) using UV-visible spectroscopy and found to be stable. FTIR analysis was performed to identify the active biomolecules that were responsible for the reduction of AgNPs. The synthesised particles were found to be spherical in shape and are in the average size range to nm and were observed to be monodispersed hence it proves that the particles were stable.
Keywords: bio-reduction; Chordia dichotoma; silver nanoparticle; antimicrobial activity.
Special Issue on: CIMDD 2013 Behaviour of Materials
Electrical properties of nanoscale field effect transistor
by Sana Kausar, Shirish Joshi
Abstract: In this paper structure of a H-passivated silicon nanowire along  direction with hexagonal cross section is defined by using Virtual nanolab (VNL), and set up a nanoscale field effect transistor (FET) structure with a wrap-around gate. Then the transmission spectrum and conductance is computed as the gate bias is varied. The device characteristic curve and conductance with respect to gate voltage is studied. Also, the effect of doping of Al atom on characteristic curve and conductance of nanoscale field effect transistor is analysed.
Keywords: silicon nanowire transistor; single electron transistor; SET; nanowire.
Special Issue on: DevIC 2017 Nanotechnology Based Devices and Nanostructures
GaAs SOI FinFET: Impact of Gate Dielectric on Electrical Parameters and Application as Digital Inverter
by RAJESH SAHA, Brinda Bhowmick, Srimanta Baishya
Abstract: In this paper, a GaAs SOI (Silicon on Insulator) FinFET is proposed. A comparative study between proposed GaAs FinFET and conventional Si FinFET is presented. The effects of dielectric constant (k) of gate dielectric material on electrical parameters like channel potential, drain current, and Ion/Ioff have been reported. Results show that as k raises, both Ion/Ioff and channel potential increases. Again the impact of k on short channel effects (SCEs) has been investigated. TCAD results show that as k increases subthreshold swing (SS) improves, drain induced barrier lowering (DIBL) degrades, and Vt roll off occur. The impacts of k on gate capacitance (CGG) and intrinsic delay (τ) have been presented and they increases as k increases. A digital CMOS inverter is implemented through proposed FinFET and the effect of k on its delay parameter is estimated. Results shows that average delay increase as k increases.
Keywords: CMOS inverter; dielectric constant; FinFET; GaAs; SOI
An Insight into the high frequency analysis of work function modulated cylindrical surrounding gate MOSFET
by Biswajit Jena, Sidhartha Dash, Guru Prasad Mishra
Abstract: The unique design along with greater accuracy in device performance has made cylindrical surrounding gate MOSFET (CSGM) a cutting edge device in the present VLSI technology. Due to its cylindrical geometry, this device provides higher packing density and higher scaling possibilities. In this work, a work function engineering based metal gate with continuous mole fraction variation along the z-axis in a cylindrical surrounding gate MOSFET (WMCSGM) is introduced. The proposed WMCSGM model exhibits improved RF performance as compared to conventional CSGM model. The static gm-VGS curve and Cgg-VGS curves are investigated clearly. The relevant electrical parameters such as threshold voltage (Vth), drain current (Id) and transconductance are extracted. Along with the electrical parameters, RF parameters and gain parameters (current gain and voltage gain) and different performance measures (cut-off frequency, maximum oscillation frequency) have been extensively investigated.
Keywords: Cut-off frequency; Maximum oscillation frequency; CSGM, WMCSGM; Work function modulation.
Variation of Optical Bandwidth in Defected Ternary Photonic Crystal under Different Polarization Conditions
by Arpan Deyasi, A. Sarkar
Abstract: Photonic bandwidth of defected one-dimensional ternary photonic crystal is analytically calculated under both types of oblique incidences. Both P and S type polarized incidences on the structure are considered in order to compute transmittivity of the proposed Butterworth type bandpass filter, and passband spectrum is kept at 1550 nm by suitably choosing structural parameters and defect density. Defect is kept within feasible limit, and ripple in the desired passband region is tailored by its controlled variation. Width of passband as function of defect density, angle of incidence and dimension of constituent layers is computed, and critical dimension for the sandwiched layer is predicted over which the structure will behave as equivalent binary one. For closely-spaced signal transmission, this narrow bandpass filter will work as excellent candidate to improve SNR.
Keywords: Optical bandwidth; Transmittivity; polarized condition; Defect density; Ternary crystal; Ripple factor
Adsorption of gaseous air pollutants over Ti-doped ZGNR structures: A DFT study
by RITWIK VATSYAYAN, RAJAN SINGH, ROY PAILY
Abstract: In this study, we employed the Density Functional Theory (DFT) to study the interactions between gaseous air pollutants, including di-atomic (CO and NO), tri-atomic (CO2 and HCN), and poly-atomic (HCHO and COCl2) species, and Ti-doped zigzag graphene nanoribbon (ZGNR) structures. During this, two types of doped structures are considered, i.e. SV-ZGNR in which Ti replaces one carbon atom and DV-ZGNR, in which Ti atom replaces two adjacent carbon atoms. All gases under consideration are observed to exhibit significant adsorption energy over doped ZGNR except COCl2 for which a catalytic dissociation is observed. Our results indicate that doped ZGNR is
better for CO, NO, and HCHO adsorption as compared to that for reported doped graphene sheet. Also, DV-ZGNR is preferred over SV-ZGNR in terms of adsorption. Moreover, due to the adsorption, changes in the density of states are observed which confirms that the Ti-doped ZGNR has potential to be used as the sensing platform for these gases.
Keywords: CO, NO, CO2, HCN, HCHO, COCl2, Adsorption, Ti-doped ZGNR, Density Functional Theory.