Editorial
Hisatoshi Kobayashi; Mikael Syväjärvi
Research Article
K. Samuvel; K. Ramachandran; V. Ratchagar; G. Ravi
Abstract
Barium Titanate doped with Cobalt is known for both its electric and magnetic properties. The synthesis and characterization of Cobalt doped barium titanate; BaTi1-xCoxO3(BTCO) x = 0.5was investigated with a view to understand its structural, magnetic and electrical properties. A finest possible sample ...
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Barium Titanate doped with Cobalt is known for both its electric and magnetic properties. The synthesis and characterization of Cobalt doped barium titanate; BaTi1-xCoxO3(BTCO) x = 0.5was investigated with a view to understand its structural, magnetic and electrical properties. A finest possible sample of Co doped micro particles of BaTiO3 (BTO) with possible tetragonal structure via a solid-state route was prepared. Prepared samples of BaTi1-xCoxO3 (BTCO) were structural characterized by X-ray diffraction (XRD). The dielectric constant measurements of the samples were carried out at 1Hz to1 MHz Vibrating Sample Magnetometer (VSM) measurements revealed the magnetic nature of Cobalt doped BaTiO3. Ferroelectric hysteresis loop traced at the electric field in-between -15 to +15 (KV/cm). The relaxation phenomena that take place cane be attributable to the damping of dipole oscillator due to the application of external field. The impedance measurements were done up to 473 K in order to separate grain (bulk) and grain boundary contributions. The FESEM micrographs show proper grain growth and EDAX confirmed the presence of all the elements in samples. In the present study, various electrical properties of barium titanate based ceramics were explained and examples of the relevant applications were given. Copyright © 2017 VBRI Press.
Research Article
Rachna Ahlawat
Abstract
Y2O3 nanocrystallite has been successfully synthesized by sol-gel technique. Y(NO3)3.4H2O and TEOS were used as precursors and obtained powdered form of the oxide. In this study, stepwise annealing process has been performed and obtained almost spherical Y2O3 nanocrystallites. As-prepared sample was ...
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Y2O3 nanocrystallite has been successfully synthesized by sol-gel technique. Y(NO3)3.4H2O and TEOS were used as precursors and obtained powdered form of the oxide. In this study, stepwise annealing process has been performed and obtained almost spherical Y2O3 nanocrystallites. As-prepared sample was annealed at 900°C and their comparison has been studied in detail. Structural investigations of the prepared nanocrystallites were carried out by XRD and TEM. Optical behavior of the sample was investigated using UV-Vis absorption spectra. Also, band gap energy Eg = 5.9 eV has been calculated using Tauc’s plot. It is expected that the studies of these phenomena would open a new vistas of energy conversion devices and high speed optoelectronic instrumentation. Copyright © 2017 VBRI Press.
Research Article
Deepika Chaudhary; Mansi Sharma; S. Sudhakar; Sushil Kumar
Abstract
In this article, we report the phase transition region of hydrogenated amorphous (a-Si:H) to nano-crystalline (nc-Si:H) silicon thin films deposited using 27.12 MHz assisted Plasma Enhanced Chemical vapor Deposition (PECVD) process with the approach of plasma diagnosis. This work presents for the first ...
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In this article, we report the phase transition region of hydrogenated amorphous (a-Si:H) to nano-crystalline (nc-Si:H) silicon thin films deposited using 27.12 MHz assisted Plasma Enhanced Chemical vapor Deposition (PECVD) process with the approach of plasma diagnosis. This work presents for the first time a study of plasma characteristics using Impedance Analyser (V/I probe) at various applied power (4 W - 40 W), though till now this apparatus has been utilized only to analyse the applied delivered power during processing. On the basis of plasma diagnose, optimum bulk field (5 V/cm); sheath field (1376 V/cm) and minimum sheath width (7.4 x 10-4 cm) observed at 20 W power which provides a visible mark of transition from a-Si:H to nc-Si:H. On account of plasma properties, the deposition was carried out by considering the plasma-surface interaction during growth. The microstructure of the deposited films was characterized using Raman spectra, UV-Vis spectra and conductivity measurements and they were found to be well correlating with the evaluated plasma characteristics. In particular, it was found that at applied power near to the onset of transition regime i.e. at 10 W, preeminent properties of a-Si:H film was observed, predominantly in terms of highest photosensitivity (7.2x103), low photo-degradation and high deposition rate (~1.39 Å/s). On the other hand, volume fraction of crystallites (24 %), wider band gap (2.0 eV) and no photo-degradation observed for the film deposited at 20 W applied power which signifies the existence of crystallites in an amorphous matrix. Copyright © 2017 VBRI Press.
Research Article
Karuna Nalwa; Anupama Thakur; Neeta Sharma
Abstract
In the present study nanoparticles of zinc oxide (ZnO) were synthesized by simple solution based approach and used as an adsorbent for the removal of Cu(II) ions from aqueous solution. ZnO nanoparticles were characterized by X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and Dynamic ...
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In the present study nanoparticles of zinc oxide (ZnO) were synthesized by simple solution based approach and used as an adsorbent for the removal of Cu(II) ions from aqueous solution. ZnO nanoparticles were characterized by X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and Dynamic Light Scattering (DLS). TEM confirmed the formation of zinc oxide nanoparticles in the size range of 10-11 nm. Adsorption capacity of ZnO for removing Cu(II) ions from aqueous solutions was investigated at different pH, as a function of contact time, metal ion concentration and the amount of adsorbent. Moreover, adsorption isotherms and kinetics was studied to understand the nature and mechanism of adsorption. A high percentage removal (98.71%) of Cu(II) from its aqueous solutions at pH 5 and at initial heavy metal ion concentration of 300 mg/l by ZnO particles was achieved. The adsorption isotherm was well described by Freundlich isotherm model(R2= 0.999). The adsorption kinetics data was well fitted by the pseudo-second-order rate model with a high regression coefficient. The above results suggest that ZnO nanoparticles can be used as potential adsorbent for the efficient removal of heavy metals from aqueous solutions. Copyright © 2017 VBRI Press
Research Article
Smriti Arora; Ritika Nagpal; Sweta Mishra; SMS Chauhan
Abstract
A fast, sensitive, label-free, and organic cationic dye adsorbent has been developed by hydrothermal sulfonation reaction on reduced graphene oxide. The layered graphene sheet provides a significant surface area, high intrinsic mobility while presence of –SO3H groups on both sides of sheet render ...
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A fast, sensitive, label-free, and organic cationic dye adsorbent has been developed by hydrothermal sulfonation reaction on reduced graphene oxide. The layered graphene sheet provides a significant surface area, high intrinsic mobility while presence of –SO3H groups on both sides of sheet render strong hydrophilicity and good dispersibility in water. The dye adsorption process is followed using UV–Visible spectroscopy, while the material before and after adsorption has been characterized by Raman, Powder XRD, FT-IR, TGA, TEM, SEM analysis. Optimum experimental parameters were determined to be acidic for Rhodamine B (RB) and basic for Methylene Blue (MB), temperature 30°C, adsorbent dosage50 mg/L. The sorption equilibrium data were modeled using various isotherms, where the data best fitted to Freundlich isotherm for RB (qmax = 76.68 mg/g), while Langmuir isotherm for MB (qmax = 564.97 mg/g). The results indicate that the heterogeneous adsorbent can be applied for efficient dye removal from industrial effluent and contaminated natural water. Copyright © 2017 VBRI Press.
Research Article
Hitesh R. Ashani; Sachin P. Parikh; Jaysukh H. Markna
Abstract
Nanotechnology is considered as one of the active research area of 21st century due to its increasing economic importance and ability to study the material at nano scale to improve its behavior in construction industry. Concrete the second highest consume commodity on the planet after water is highly ...
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Nanotechnology is considered as one of the active research area of 21st century due to its increasing economic importance and ability to study the material at nano scale to improve its behavior in construction industry. Concrete the second highest consume commodity on the planet after water is highly heterogeneous material with thumping performance challenges on it. Demand of concrete is increasing due to increasing demand for infrastructure development, rapid urbanization, rapid industrial development, population growth, economic development of the nation etc. A little diminution in the number of problems related with concrete would add up to noteworthy recital enhancement and economic benefits to society and nation. In the present communication, the cement one of the main ingredient of concrete was replaced with a range of5%, 10%, 15% and 20 % of the weight of cement by nano carbon material to study the effect on the mechanical properties like – compressive strength, surface hardness, water absorption, consistency, morphology on nano carbon concrete specimen. A rapport was made between standard and nano carbon black concrete specimen to arrive at a legitimate conclusion that improvement in the mechanical properties like strength, hardness, compactness etc. and C-S-H gel structure is obtained. Copyright © 2017 VBRI Press.
Research Article
Mrinal K Adak; Sujoy Chakraborty; Shrabanee Sen; Debasis Dhak
Abstract
Zirconium-aluminium modified iron oxide nano adsorbent was synthesized using chemical route using zirconyl nitrate, aluminium nitrate, ferric nitrate and triethanol amine. The precursor materials were calcined at 900oC for 4 h to obtain a carban free nano-adsorbent. XRD of the calcined powder was ...
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Zirconium-aluminium modified iron oxide nano adsorbent was synthesized using chemical route using zirconyl nitrate, aluminium nitrate, ferric nitrate and triethanol amine. The precursor materials were calcined at 900oC for 4 h to obtain a carban free nano-adsorbent. XRD of the calcined powder was performed to detect the phase and to estimate the crystallite size. Fluoride removal tests were performed using synthesized fluorinated aqueous solutions of 3 ppm, 5 ppm and 10 ppm. The adsorbent dose was considered 15 mints, 30 mints, 45 mints and 60 mints while adsorbent dose were varied from0.1 mg to 0.3 mg for every 100 ml fluorinated aqueous solution. FTIR spectroscopy of the nano-adsorbent was studied before and after fluoride removal. Percentage of fluoride removal was checked for at least three cycles using the same adsorbent. Fluoride concentration of treated aqueous solution was studied using UV-Visible spectrometer using standard zirconium alizarin S solution. Maximum % of fluoride removal was observed up to 99.9% for an adsorbent dose 0.3 mg for a contact time of 15 minutes at 3 ppm fluoride concentration. However, the adsorbent dose for highest % of fluoride removal depends highly on the contact time and initial fluoride concentration and they were found to be very selective. The synthesized nano-sdsorbent could be used commercially for effective fluoride removal from fluorinated water for drinking purpose. Copyright © 2017 VBRI Press.
Research Article
Narendra Singh; Davinder Kaur
Abstract
Ultrathin silicon carbide (SiC) films were grown on p type Si (100) substrate by RF magnetron sputtering at constant substrate temperature of 7000C for investigating thickness dependence of structural and photoluminescence properties. The structural and Photoluminescence properties were measured by X-ray ...
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Ultrathin silicon carbide (SiC) films were grown on p type Si (100) substrate by RF magnetron sputtering at constant substrate temperature of 7000C for investigating thickness dependence of structural and photoluminescence properties. The structural and Photoluminescence properties were measured by X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and photospectrometer respectively. X-ray diffraction pattern revealed (102) and dominant (105) reflections which corresponds to 4H-SiC and an enhancement in (105) peak intensity with increasing thickness was also observed. The thickness measured by X-ray reflectometry (XRR) reduces from ~ 46 nm to 12 nm by decreasing deposition time (40-10 minute) which in turn reduces the crystallite size. Photoluminescence spectra show a broad peak extending from ultraviolet to blue region centered at ~ 385 nm for film of thickness ~ 46 nm (deposition time 40 min). A shifting in Photoluminescence peak towards shorter wavelength (blue shift) with decreasing SiC ultrathin film thickness was observed, which could be attributed to quantum confinement effect. The improved Photoluminescence in ultrathin nanocrystalline SiC films could make it a potential candidate in optoelectronic and biomedical applications. Copyright © 2017 VBRI Press.
Research Article
Udayraj C. Yadav; Yuvraj S. Malghe
Abstract
Nanosized barium cerate (BaCeO3) was prepared from barium cerium oxalate (BCO) precursor. Thermal decomposition of BCO precursor was studied using thermogravimetry(TG), differential thermal analysis (DTA), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) techniques. BCO precursor ...
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Nanosized barium cerate (BaCeO3) was prepared from barium cerium oxalate (BCO) precursor. Thermal decomposition of BCO precursor was studied using thermogravimetry(TG), differential thermal analysis (DTA), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) techniques. BCO precursor calcined at 1000°C for 2h gives nanosized BaCeO3 powder. Band gap of BaCeO3 was estimated using diffuse reflectance spectrophotometry and is found to be2.17 eV. Particle size distribution study reveals that particle size of BaCeO3varies between 10-70 nm. Dielectric behavior of BaCeO3 was studied with varying the temperature at different frequencies. BaCeO3 shows good dielectric and conductivity response. Copyright © 2017 VBRI Press.
Review Article
Brijesh Prasad; Bhingole P P
Abstract
Magnesium and its alloys have got great attention in recent times due to its potential to replace heaver alloys with equal strengths and lighter in weight, hence become potential materiel automobile, sports, aeronautical and biomaterials applications This study concentrates and summarizes ...
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Magnesium and its alloys have got great attention in recent times due to its potential to replace heaver alloys with equal strengths and lighter in weight, hence become potential materiel automobile, sports, aeronautical and biomaterials applications This study concentrates and summarizes the fundamental properties of magnesium and its alloys such as high strength, ductility non-corrosive behavior etc. Along with its developments in its physical metallurgy, forming process and strengthening mechanisms to enhance the mechanical strength followed by behavior of magnesium alloys under different working conditions and applications. A brief overview of the recent and systematic outline is reported for improvement of mechanical by strengthening mechanism along with its applications. This work would be very much helpful for the researchers to find the best strengthening method on looking on its various aspects of design, environment friendly behavior and optimum utilization of resources with saving the natural resources. Copyright © 2017 VBRI Press.
Research Article
Bikash Mandal; Indranarayan Basumallick; Susanta Ghosh
Abstract
Present study reports an easy and cost-effective method of synthesis of Li4Fe(CN)6 cathode from K4Fe(CN)6.3H2O and LiClO4 in aqueous medium for its use in lithium-ion battery. The synthesized Li4Fe(CN)6 is characterized by UV-Vis, FTIR and cyclic-voltammetry studies. A special laboratory model lithium-ion ...
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Present study reports an easy and cost-effective method of synthesis of Li4Fe(CN)6 cathode from K4Fe(CN)6.3H2O and LiClO4 in aqueous medium for its use in lithium-ion battery. The synthesized Li4Fe(CN)6 is characterized by UV-Vis, FTIR and cyclic-voltammetry studies. A special laboratory model lithium-ion battery is designed, where aqueous Li4Fe(CN)6 solution acts as a cathode, metallic lithium as anode and 1 molar solution of LiPF6 dissolved in water immiscible ionic liquid, 1-Butyl-3-methylimidazolium hexafluorophosphate (BMIM-PF6) as electrolyte. The cell exhibits an open circuit potential of 3.12 volt and a good charge-discharge cycling behaviour. The cell delivered a maximum discharge capacity of 86 mAhg-1 (theoretical capacity 112 mAhg-1) at 0.2 C rates with an average discharge potential of 2.1 volts. Although the ionic liquid is a little bit cost intensive, but the easy synthesis methodology with the cheapest raw materials and overall cycling efficiency, makes this technology available as a green economical energy storage device in the current battery industry. Copyright © 2017 VBRI Press.
Research Article
Rajnish Kumar; S. A. R. Hashmi; Subhash Nimanpure; Ajay Naik
Abstract
Randomly distributed kenaf fibre with varying length (5-50mm) and weight fractions (25-40%) were used to reinforce epoxy resin to prepare environment friendly composites. Effect of fibre length with constant fibre loading on dynamic mechanical properties was studied and its effect on storage modulus, ...
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Randomly distributed kenaf fibre with varying length (5-50mm) and weight fractions (25-40%) were used to reinforce epoxy resin to prepare environment friendly composites. Effect of fibre length with constant fibre loading on dynamic mechanical properties was studied and its effect on storage modulus, loss modulus and damping factor were investigated. Kenaf fibres were also subjected to alkali treatment to improve interaction with the epoxy resin. The mechanical properties of composites improved with the length and loading of fibres. Tensile strength, flexural strength and impact strength of composites at 40 wt% of fibre reinforcement improved by 46, 51 and 97% as compared to the composites containing 25 wt% of kenaf fibre. It was also observed that fibre folds developed during mixing became significant factor which limited the improvement in mechanical strength of kenaf epoxy composites. A few important predictive models namely rule of mixture, Haplin-Tsai, Nielson Chen and Manera models were compared with the experimental values obtained in this present study. Manera model predicted the experimental data most accurately. Alkali treatment improved the interface and its outcome reflected in the improved modulus that increased 21.76% in samples having 10mm length of kenaf fibre. Copyright © 2017 VBRI Press.