Editorial
Hisatoshi Kobayashi; Mikael Syväjärvi
Abstract
When we write this, the American Advanced Materials Congress 2016 (AAMC 2016) (www.vbripress.com/aamc) has just been successfully carried out in December 04 - 09, 2016.It was conducted for the first time. The team at VBRI Press (www.vbripress.com) and International Association of Advanced Materials (IAAM, ...
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When we write this, the American Advanced Materials Congress 2016 (AAMC 2016) (www.vbripress.com/aamc) has just been successfully carried out in December 04 - 09, 2016.It was conducted for the first time. The team at VBRI Press (www.vbripress.com) and International Association of Advanced Materials (IAAM, www.iaamonline.org) used the experience and learning from the European Advanced Materials Congress to create an efficient program. This was indeed a challenge since most team members are located in Sweden and full team was not available. Now the IAAM office in US is being built up and we aim to use the American office to create an efficient team for organization of various events in US.
Research Article
Suresh R. Ambalam; Rajendran I. Gounder
Abstract
Low alloy steel is used in industrial applications to manufacture bearing materials, bushes, gears, etc. In this work, an attempt has been made to characterize powder metallurgy (PM) processed low alloy steel impregnated with solid lubricant WS2 in four different weight proportions (0, 2.5, 5 and 10%) ...
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Low alloy steel is used in industrial applications to manufacture bearing materials, bushes, gears, etc. In this work, an attempt has been made to characterize powder metallurgy (PM) processed low alloy steel impregnated with solid lubricant WS2 in four different weight proportions (0, 2.5, 5 and 10%) using nano-indentation. Results of nano-indentation were correlated with impregnated quantity of WS2 and micro structural phases in sintered low alloy steel. The values of elastic moduli and contact stiffness were found to be higher in the PM-processed low alloy steel impregnated with WS2 compared with the low alloy steel without WS2. Ferritic and pearlitic phases in the microstructure were observed in low alloy steel impregnated with 0 % WS2. Larger proportion of martensitic phase was observed in the microstructure of low alloy steel impregnated with 5 and 10 % of WS2. The specimen with2.5 % WS2 by weight has the highest hardness and the highest elastic modulus of all the proportions tested, which may be attributed to predominant bainitic structure present in it. Hence the PM-processed low alloy steel impregnated with 2.5 % WS2 would be more suitable composition for manufacturing sliding members due to its superior mechanical properties. Copyright © 2017 VBRI Press
Research Article
Vipin Jain; Anil Kumar; Ajay Dhar
Abstract
Graphene possesses excellent properties such as, high Young’s modulus (1 TPa), high fracture strength (~125 GPa) and extreme thermal conductivity (~5000 W/m/K), therefore, can serve as an ideal reinforcement material for the metal based High Tech structural nanocomposites. In the present work, ...
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Graphene possesses excellent properties such as, high Young’s modulus (1 TPa), high fracture strength (~125 GPa) and extreme thermal conductivity (~5000 W/m/K), therefore, can serve as an ideal reinforcement material for the metal based High Tech structural nanocomposites. In the present work, a novel chemical synthesis method has been adopted for the in-situ synthesis of aluminium-graphene (Al-Gr) nanocomposite powders with varying compositions using graphene oxide (GO) as the precursor. The pure aluminium powder was initially cryomilled to refine the crystallite size. Subsequently, Al-reduced graphene (Al-Gr) nanocomposite powders were synthesized employing different volume proportions of GO (referred as 0.5, 2, 4, and 6 ml) dispersed in deionized water. The synthesized nanocomposite powders were ball milled followed by consolidation using spark plasma sintering under the optimized conditions. The nanocomposite powder as well as SPSed samples were characterized using X-ray diffraction (XRD), Raman Spectroscopy and electron microscopy. Scanning electron microscopy (SEM) studies of nanocomposite powders have depicted wrinkled structure typical of reduced graphene. Raman spectra have shown regular D, G, 2D and D+G bands and a modulated 2D peak having intensity significantly less than the G peak was observed for the nanocomposite powders confirming multilayered graphene is synthesized. The graphene wrinkles were determined in the size of 100 nm or more. Microhardness of SPS sintered nanocomposites is found progressively increased with the increasing content of reduced graphene with up to 58% improvement over pure Al was observed for the maximized GO content depicting potential for energy efficient high strength applications. The synthesized Al-graphene nanocomposites are novel in terms of an innovative, indigenously developed and scalable to bulk synthesis approach based on in-situ chemical synthesis route adopted. Copyright © 2017 VBRI Press.
Research Article
Prashant Rawat; Kalyan K. Singh; Nand K. Singh
Abstract
Damage induced in symmetrical and asymmetrical glass fiber reinforced polymer (GFRP) laminate overlow-velocity impact (LVI) using a mild steel impactor is investigated. Numerical simulation is done using 3-Dfinite element analysis software LS-DYNA. Orientations for symmetrical and asymmetrical laminate ...
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Damage induced in symmetrical and asymmetrical glass fiber reinforced polymer (GFRP) laminate overlow-velocity impact (LVI) using a mild steel impactor is investigated. Numerical simulation is done using 3-Dfinite element analysis software LS-DYNA. Orientations for symmetrical and asymmetrical laminate were [(0,90)/(+45,-45)/(+45,-45)/(0,90)//(90,0)/(+45,-45)/(+45,-45)/(90,0)] and [(0,90)/(+45,-45)/(+45,-45)/(0,90)//(+45,-45)/(90,0)/ (90,0)/(+45,-45)] respectively. Two samples each from symmetric and asymmetric laminate with and without pre-crack were numerically simulated. Induced circular pre-crack was modeled in the midplane of the laminate. A circular specimen of radius 75mm with clamped area of 376mm2 is modeled. The velocity of 5 m/sec was assigned to the hemispherical headed cylindrical impactor. The result shows that symmetrical laminates absorb high energy and damage area for it is 24.06 % less than asymmetrical laminate for laminate with pre-crack in mid plate. This study concluded symmetrical laminate design is better for structural purpose as compared to asymmetrical design. Results of proposed investigation are directly applicable in aircraft, automobiles and space equipment. Copyright © 2017 VBRI Press.
Research Article
S. C. S. P. Kumar Krovvidi; G. Padmakumar; A. K. Bhaduri
Abstract
Bellows find wide applications in reactor systems such as in bellows sealed valves as primary leak tight barriers and in piping systems to absorb differential thermal expansions. Reliable operation of bellows is strongly dependent of proper material selection. Various candidates for material of the bellows ...
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Bellows find wide applications in reactor systems such as in bellows sealed valves as primary leak tight barriers and in piping systems to absorb differential thermal expansions. Reliable operation of bellows is strongly dependent of proper material selection. Various candidates for material of the bellows are austenitic stainless steels (such as SS316, SS304, SS316Ti, SS304L etc.), precipitation hardened stainless steels (such as AM350) and Nickel base alloys such as Inconel-718 and Inconel-625. This paper presents the review of the operating experience, mechanical & neutronic properties of various materials for bellows in nuclear industry. In this work, it is observed that Inconel alloys have superior mechanical properties than austenitic stainless steels but exhibit neutron embrittlement. Hence, use of Inconel bellows is limited to low neutron fluence applications. Precipitation hardened steels such as AM350 have high mechanical strength but lesser ductility. Though AM350 is not suitable for formed bellows, it has excellent operating experience for welded disc bellows in nuclear applications. Austenitic stainless steels have large operating experience. Variants of SS316 are used for high temperature and variants of SS304 are used for temperatures below creep range. ‘L’ grades or stabilized grades are used for resistance to sensitization during welding. Based on the present review work, guidelines for selection of material for bellows are drawn, satisfying the selection criterion. Copyright © 2017 VBRI Press.
Research Article
Sunita Khangembam; Maisnam Victory; Waikhom Surchandra; Sumitra Phanjoubam
Abstract
Recent technological breakthroughs and the desire for new functions generate an enormous demand for synthesizing new materials through different ways and methods which show superior properties compared with their pure counterparts. Presently, polycrystalline zinc doped nickel ferrites having the compositional ...
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Recent technological breakthroughs and the desire for new functions generate an enormous demand for synthesizing new materials through different ways and methods which show superior properties compared with their pure counterparts. Presently, polycrystalline zinc doped nickel ferrites having the compositional formula Ni1-xZnxFe2O4 where x = 0.0, 0.1, 0.2 and 0.4 were synthesized. Sol-gel auto combustion method was adopted for the preparation of these ferrites since it provides a simple and economic alternative technique ensuring good stoichiometric control, production of particles with narrow size distribution in a relatively shorter time, good homogeneity and high sinterability at lower temperature. Structural studies were carried out by XRD. Various structural properties like lattice parameter, crystallite size and density were calculated from the XRD data. Micro structural studies were carried out using Scanning Electron Microscopy (SEM), while the elemental compositions of all the samples were studied by Energy Dispersive X-ray Analysis (EDAX). The frequency variation of room temperature dielectric constant and dielectric loss was studied in the frequency range 100Hz – 1MHz and dispersive behavior was observed. The room temperature dc resistivity of all the samples was also investigated. Zn substituted nickel ferrites are found to be useful in microwave and electronic devices. Copyright © 2017 VBRI Press.
Research Article
Hiranand R. Khambayat; Pravin S. More; Bandoba T. Nikam
Abstract
In this manuscript we have investigated the fabrication of PEO embedded planar optical waveguide (POW) sensor. To improve the sensing characteristics of POW, it has coated with conducting polymer poly ethylene oxide (PEO). The embedded waveguide prepared with variant thermal ion exchange process with ...
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In this manuscript we have investigated the fabrication of PEO embedded planar optical waveguide (POW) sensor. To improve the sensing characteristics of POW, it has coated with conducting polymer poly ethylene oxide (PEO). The embedded waveguide prepared with variant thermal ion exchange process with various time duration of 20,40,60,80,100,120 minutes on sodium silicate glass. The properties of modified planar optical waveguideenhance the sensing activity, which can help to study the characteristics of soil by doping of different fertilizerswith x wt% (x=1, 2, 3, 4, 5) of varying concentrations. The use of appropriate percentage of fertilizer in differentsoil yield good healthy crop. The laser technique is used to study the POW for characteristics of soil. The material characterization study done by scanning electron microscopy (SEM) and small angle X-ray diffraction (XRD) revealed the formation of K+ ions layer in surface-near regions of the sample at optimum expose time period of 120 minutes at 380 0C. It gives an advantageous application for unidentified soil character analysis. Copyright © 2017 VBRI Press.
Research Article
Poonam R. Kharangarh; Akshay Kumar; Raj K. Sharma; Gurmeet Singh
Abstract
With an objective to develop electrode materials with high specific capacitance and good stability, we prepared Graphene quantum dot-doped with transition metal of HCl by using a facile hydrothermal at different temperatures (~ 800C- 1400C). Samples were characterized by Raman spectroscopy, Powdered ...
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With an objective to develop electrode materials with high specific capacitance and good stability, we prepared Graphene quantum dot-doped with transition metal of HCl by using a facile hydrothermal at different temperatures (~ 800C- 1400C). Samples were characterized by Raman spectroscopy, Powdered X-ray Diffraction (PXRD), U-V Visible Spectroscopy, and Transmission Electron Spectroscopy (TEM). Raman spectroscopy study reveals intensity ratio alters with changes in temperatures. It was found the variation in size with doped GQDs under different temperature conditions from TEM measurements. The observed blue shifts in the energy gap of HCl doped GQDs at higher temperature are attributed to the strong interaction of GQDs with HCl. Electrochemical studies showed a superior strategy for generating transition metals doped GQDs. The higher electrochemical activity has been originated by using cyclic voltammetry of HCl doped GQDs at 1200C and is found to be superior electrodes than all other heated samples. The simplicity of synthesized material suggests electrode to understand the charge storage mechanism for commercial applications. Copyright © 2017 VBRI Press.
Research Article
Eagambaram Murugan; Chennakesavapuram R Akshata; Annie Stephy
Abstract
Capecitabine (CPT) is an oral antineoplastic prodrug of 5-Flurorouracil (5-FU), administered for the treatment of metastatic breast and colorectal cancers. Detection of trace quantity of Capecitabine in pharmaceutical drug dosages is very crucial and essential owing to its life threating toxic adverse ...
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Capecitabine (CPT) is an oral antineoplastic prodrug of 5-Flurorouracil (5-FU), administered for the treatment of metastatic breast and colorectal cancers. Detection of trace quantity of Capecitabine in pharmaceutical drug dosages is very crucial and essential owing to its life threating toxic adverse effects. In this study, an effective conducting nanohybrid namely, MWCNT-PAMAM (G3)-AuNps was developed and characterized by Raman, FT-IR, SEM and HR-TEM techniques. The developed conducting nanohybrid was used for fabrication of effective and stable active electrode viz., GCE-MWCNT-PAMAM (G3)-AuNps which in turn demonstrated for effective sensing of trace quantity of Capecitabine i.e., at a concentration of 5 x 10-12 M under lower potentials. The reduction of Capecitabine was investigated through cyclic voltammetry in the presence of H2SO4 (pH 1.54) as supporting electrolyte. The presence of Capecitabine exhibited an irreversible reductive peak potential at ~0.835 V which was observed from mixed diffusion-adsorption controlled processes. The mechanism for electrochemical-chemical reduction, trace and rapid determination of Capecitabine are reported. This newly developed electrode has a potential to sense/ detect the Capecitabine at the concentration of 5 x 10-12 M under lower potentials. Further, it is expected that there is a strong scope for quality control in pharmaceutical formulates. Copyright © 2017 VBRI Press.
Research Article
Niranjana M; Sharanappa Chapi; Yesappa L; Archana K; Raghu S; Devendrappa H
Abstract
Polyaniline (PANI) composites doped with Vanadium pentoxide (V2O5) of different weight percentage using dodecylbenzene sulfonic acid (DBSA) as surfactant was prepared by in-situ chemical oxidation reaction method. Here ammonium persulphate was used as an oxidizing agent. The formation of composite (PANI/DBSA/V2O5) ...
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Polyaniline (PANI) composites doped with Vanadium pentoxide (V2O5) of different weight percentage using dodecylbenzene sulfonic acid (DBSA) as surfactant was prepared by in-situ chemical oxidation reaction method. Here ammonium persulphate was used as an oxidizing agent. The formation of composite (PANI/DBSA/V2O5) was confirmed with the help of analytical studies like scanning electron microscopy (SEM) and UV/Vis spectroscopy. SEM images show a substantial change in PANI morphology after incorporation of vanadium pentoxide. The optical characterizations by UV-Vis absorption spectroscopy show the increased absorption with addition of V2O5. The electrical conductivity has been studied in the frequency range of 20 Hz to 1MHz and it is found that PANI/DBSA:2%(V2O5) shows high electrical conductivity compared to pure PANI and other composites. It is observed that the dielectric constant and dielectric loss increase with concentration of V2O5. PANI/DBSA/V2O5 composites are most promising material for many electrical and potential applications. This semiconducting polymer combination of PANI and Vanadium pentoxide (V2O5) which produce hybrid material, behaves as semiconductor at low temperatures; this behavior is predicted by results of dielectric properties studied. Copyright © 2017 VBRI Press.
Research Article
Suresh Addepalli; Lakshmi Ganapathi Kolla; Uthanna Suda
Abstract
Aluminium titanate (Al2TiO5) thin films were deposited at room temperature by DC reactive magnetron sputtering. To make appropriate films for potential gate dielectric applications, we investigated the influence of annealing temperature on the structural, chemical and dielectric properties of Al2TiO5 ...
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Aluminium titanate (Al2TiO5) thin films were deposited at room temperature by DC reactive magnetron sputtering. To make appropriate films for potential gate dielectric applications, we investigated the influence of annealing temperature on the structural, chemical and dielectric properties of Al2TiO5 thin films. From XPS studies, in as-deposited films, it has been observed that the presence of Al3+ and Ti4+oxidation states which correspond to Al2O3 and TiO2 respectively. After annealing at 400 °C in oxygen ambient, the binding energies of Al 2p, Ti 2p and O 1s were shifted by ~ 1 eV towards lower binding energy. This indicates the formation of an intermediate compound of Al2O3 and TiO2. The extracted Al, Ti and O ratio was 2:1:5 and it confirms the formation of Al2TiO5. XRD studies indicate that the as-deposited films were amorphous in nature. After annealing at 400 °C, diffraction peak at 2θ = 50.6° along (200) plane corresponds to aluminum titanate (Al2TiO5) has been observed. Metal-Insulator-Semiconductor (MIS) capacitors were fabricated and characterized to estimate the dielectric properties of the deposited films. The as-deposited films show low dielectric constant (κ = 8.1) and high leakage current density (J = 2.4x10-2 A/cm2 at -1V) values. After annealing at 400 °C the films show improved dielectric constant (κ = 9.4) and leakage current density (J = 4.6x10-9 A/cm2 at -1V) values. The enhancement in the device properties can be attributed to the improved oxide and interface quality after annealing. Equivalent oxide thickness (EOT) of less than 1nm is required to use Al2TiO5 as an alternate gate dielectric to SiO2 in CMOS industry. To achieve this scaling of the dielectric thickness (<5 nm) is needed, which is under investigation. Copyright © 2017 VBRI Press.
Research Article
Nidhi Gupta; Rakhi Grover; Dalip S. Mehta; Kanchan Saxena
Abstract
Here we present fabrication of one dimensional photonic band gap structure (1D-PBG) based on periodic layers of silver and magnesium fluoride (MgF2) for tuning the emission of polyfluorene derivative, Poly(9,9-dioctylfluorenyl-2,7-diyl) (PFO). Transmittance measurements were used to characterize the ...
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Here we present fabrication of one dimensional photonic band gap structure (1D-PBG) based on periodic layers of silver and magnesium fluoride (MgF2) for tuning the emission of polyfluorene derivative, Poly(9,9-dioctylfluorenyl-2,7-diyl) (PFO). Transmittance measurements were used to characterize the photonic band gap. 1D-PBG structure with varying thickness of silver was fabricated on the back side of PFO coated glass substrate. Photoluminescence studies confirmed that blue emission was enhanced while the secondary peaks were suppressed. Photoluminescence spectra shows that the blue to green peak intensity ratio was improved by 1.7 times approximately with PBG. These type of PBG structures can be used to enhance the color purity of PFO based blue organic light emitting diodes. Copyright © 2017 VBRI Press.
Research Article
Ramakanth Illa; Jaroslav Hamrle; Jaromir Pištora
Abstract
Nanostructured thin films of MnFe2O4 were fabricated using chemical approach. Structural, magnetic, optical and magneto-optical properties of the films have been investigated using XRD, AFM, VSM, spectroscopic ellipsometry and MOKE spectroscopy. Structural evaluation of the thermally annealed films showed ...
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Nanostructured thin films of MnFe2O4 were fabricated using chemical approach. Structural, magnetic, optical and magneto-optical properties of the films have been investigated using XRD, AFM, VSM, spectroscopic ellipsometry and MOKE spectroscopy. Structural evaluation of the thermally annealed films showed crystalline phase and spinel structure along with appearance of textured nano-crystallites at the annealing temperature (Ta) of 500 °C and above. Surface morphology of the films annealed at 600 oC was characterized using AFM and the size of MnFe2O4 particles was observed to be 70 – 180 nm with ellipsoidal morphology and the surface roughness was found to be 8 nm. Hysteresis loops of the ferrite films indicated ferromagnetic behavior for annealing temperature of 400 oC and above, with a small contribution of paramagnetic nature arising from its oxide. The films showed a semiconducting behavior for the annealing temperature (Ta) ranging from 400 - 600 oC. The magneto-optical response is found to be small, i.e., one order less when compared to CoFe2O4 or metallic Fe, Co films. The maximum magneto-optical response from MnFe2O4 thin films is found for Ta = 400 oC, i.e. for incomplete spinel structure. As the material used for making the thin film coating is of the order of very few milligrams, these highly responsive films could be used as magnetic sensors. Copyright © 2017 VBRI Press.
Research Article
Biju Thangjam; Ibetombi Soibam
Abstract
Ni-Cu-Zn ferrites with compositional formula Ni0.8-xCuxZn0.2Fe2O4, where 0.0≤x≤0.5 in steps of 0.1 were synthesized by the citrate precursor method. The samples were subjected to final sintering at 900ᵒC for 2h after a pre-sintering at 600ᵒC for 4h. X-ray diffraction patterns confirmed the ...
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Ni-Cu-Zn ferrites with compositional formula Ni0.8-xCuxZn0.2Fe2O4, where 0.0≤x≤0.5 in steps of 0.1 were synthesized by the citrate precursor method. The samples were subjected to final sintering at 900ᵒC for 2h after a pre-sintering at 600ᵒC for 4h. X-ray diffraction patterns confirmed the formation of single phase spinel structure. The average crystallite size was calculated using Scherrer’s formula and was found to vary from 33nm to 39nm, clearly indicating the formation of nanoparticles. The infrared spectra were recorded at room temperature for all the samples in the range of 450 cm‾1 to 4000 cm‾1 using Perkin Elmer FT-IR Spectrometer. Jahn-Teller effect emerges which can be identified through the FT-IR Spectroscopy of the samples. This phenomenon may result in useful electro and magneto- optical applications. Possible mechanism is being discussed. Copyright © 2017 VBRI Press.
Research Article
Pooja Saini; Khobaib .; Prikshit Gautam; Manjari Singh; Ram P. Tandon; S. P. Singh; Ajit K. Mahapatro
Abstract
This work explains the functionalization of polyallylamine (PAA) on the graphene oxide (GO) sheets following a chemical route. The resulting GO-PAA complex is characterized by using various imaging and analytical tools. In the Raman spectroscopy for both the GO and GO-PAA, the appearance of D and G characteristic ...
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This work explains the functionalization of polyallylamine (PAA) on the graphene oxide (GO) sheets following a chemical route. The resulting GO-PAA complex is characterized by using various imaging and analytical tools. In the Raman spectroscopy for both the GO and GO-PAA, the appearance of D and G characteristic bands correspond to the sp2 and sp3 contents, respectively, in the carbon sheets. The observation of lowered D/G peak intensity ratio of these peaks from 1.3 for GO to 1.1 for GO-PAA indicates the lowering of the D favored sp2 content in the GO sheet after PAA functionalization. In the Fourier transform infra-red spectroscopy, the disappearance of the vibrational modes for ketone and carboxyl groups, and appearance of the amine (-NH) group confirms the chemical interaction of GO and PAA triggered with the -NH group of PAA interacting with the oxygen contained hydroxyl, epoxy, and carboxylic groups of the GO sheets to form the GO-PAA complex. Scanning electron microscopy imaging indicates opaque layers with no distinction of flakes after PAA functionalization. Copyright © 2017 VBRI Press