Table of Contents - Volume 16 Number 1

Hide Abstract

Hide Abstract

In this study, graphene oxide (GO) reinforced epoxy loaded poly(urea-formaldehyde) microcapsules have produced by easy and cost-effective one step in-situ emulsion polymerization method without emulsifier agent. Low amounts of GOhas incorporated into microcapsules without pre-treatment or ultra-speed agitation step. The effect of GO reinforcement on microcapsule size, shell structure, morphology, and thermal behaviour analyzed with Fourier transform infrared spectrometer (FTIR), scanning electronic microscope (SEM) and thermal gravimetric analysis (TGA), respectively. Results revealed that obtained microcapsules are resistant up to 225 °C. Besides, also, the addition of a certain amount of GO (0.5%, wt/ wt) forms pretty small sized (3-4 µm) microcapsules with a smooth surface, since GO nanoparticles act as a surfactant material. On the other hand, by increasing the amount of GO up to 1% (w / w), higher shell thickness was caused due to the coating of the GO layers into the shell. Produced GO-reinforced epoxy loaded microcapsules could be used in self-healing composites and also anticorrosion coatings.

Hide Abstract

This paper highlights the recenttrends followed by CSIR- Central Glass & Ceramic Research Institute (CGCRI) in establishing Solar Photo-Voltaic Power Plants. This work is aimed at meeting up the conventional energy scarcity at CSIR-CGCRI, SIRSA Campus and developing clean/green energy in order to compensate the global challenges of energy scarcity, climate change and renewable energy development.Abiding by the scheme of Jawaharlal Nehru National Solar Mission (JNNSM) under the aegis ofMinistry of New & Renewable Energy (MNRE), CSIR-CGCRI has implemented Solar Roof-top Grid connected Power Plant at SIRSA Residential staff quarter since February 2014 with the capacity of 37.5KWp (as per agreement). From September 2017, CSIR-CGCRI hasfurther enhanced the capacity to 100.5KWp (as per agreement). Results revealed that there is a stable growth of solar power energy generation. Keeping this in mind, the work pertains to the basic objectives of achieving reduction in carbon food printin line with clean energy generation which leads to reduction in air-pollution and global warmingand at the same time conservation of conventional resources, which is getting reduced day-by-day.Nevertheless, the solar energy generated would eventually lessen the amount of energy purchased from the local Distribution Company (DISCOM) which would benefit our organisation economically. 

Hide Abstract

Perovskite calcium copper titanate posses giant dielectric constant making it a suitable candidate for possible applications in microelectronic components, advanced transistors, energy storage capacitors. Generally, this grade of material is synthesized by the chemical route to improving homogeneity, controlled size growth for enhanced properties. In the present research, a simple synthesis process was adopted using precursors of high purity oxides like Calcium carbonate, titania, Copper oxide without any use of complicated synthesis routes and costly chemical precursors. The molar ratio of oxides used was about 1:3:4 with mechano-chemical activation in an agate mortar for 20, 25 and 30 hours respectively in dry condition. After milling, powders obtained were made to undergo annealing at a fixed temperature of 900°C for 26 hours soaking period. Phase analysis was carried to determine the phase along with crystallite size calculation. Bonding information of the synthesized sample was analyzed to obtain the M-O coordination and vibration-stretching analysis of the bonds. Morphological features were also noted using FESEM (Field Emission Scanning Electron Microscopy) for understanding grains and granular boundaries. Both FTIR (Fourier Transform Infra-Red Spectroscopy) and XRD (X-Ray Diffractogram) analyses confirm the compound formation in terms of molecular structure responsible to obtain the proper phase.

Hide Abstract

Cyanide is one of the most used reagents in the precious metal extraction process; as well as the most efficient from the point of view of the dissolution process, but it is also a toxic product that requires a lot of care in handling. Likewise, the residual solutions of the process must be followed because they can be a risk of contamination of water, animals and human health. In the artisanal processes of obtaining gold and silver, neutralization of the residual solutions is used to passivate the present cyanide. During this process ammonium cyanate is formed which decomposes rapidly in the presence of air and sunlight in carbon dioxide and ammonia gas, contributing to the greenhouse effect. In this work, the use of the ammonium cyanate obtained in the process of neutralization of the cyanide solutions as a reagent to obtain urea is proposed. Urea was obtained indirectly through the use of the reagent kit UREA/BUN-COLOR. The process is effective at pH ≤ 4.5 with a rapid increase in solution temperature and the addition of hydrogen peroxide. The urea crystals begin to form at 50°C. The cyanide/urea ratio obtained was 1/7.5.

Hide Abstract

In the current study, sodium borate-bonded highly open porous ceramics successfully produced by starch consolidation technique. Open porous ceramic production was carried out by using an economical grade a-Si₃N₄, corn starch, CC31 commercial-grade kaolin, and borax decahydrate (Na₂B₄O₇.10H₂O). Borax decahydrate was used as a sintering aid in the system and total ceramic (a-Si₃N₄ + CC31): borax decahydrate ratio was kept constant at 5:1. Sintering studies of the shaped samples carried out in an air atmosphere at a relatively low sintering temperature, 1100°C, for one hour. Scanning electron microscopy investigations of the porous ceramic samples revealed that due to the high amount of borax based sintering additive a significant amount of liquid phase formed during the sintering process of the designed ceramics. Highly open porous(~66-74%) and lightweight(~0.64-0.83 g/cm³) ceramics were produced via starch consolidation technique and low-temperature sintering at atmospheric conditions.

Hide Abstract

The tilt angle tool on Aluminum A5083 and Copper C11000 joint processed by Friction Stir Welding (FSW) was observed in this study. The rotation speed and transverse speed were used as a parameter process for 2500 rpm and 30 mm/min, respectively. The tensile test and microstructure observation were carried out to determine the tensile strength and metal flow on Al-Cu joint, respectively. The result shows that the highest tensile strength was in 2^o tilt angle tool for 105 MPa. Its fracture surface was more close to Al and formed brittle formation.The metal flows of Al-Cu with 0^o and 2^o were not homogeneous and formed an agglomeration of Cu particle to Al surface.

Hide Abstract

Composite materials are replacing traditional materials, because of their superior physical and mechanical properties. The main objective of the present work is to perform stress-strain analysis on Styrene-Ethylene-Butylene-Styrene (SEBS)-epoxy resin composites under reinforcement of fibres and dispersion of CuO, ZnO, MgO, SiO and TiO₂nano metal oxides. Combination of glass fibre with particle reinforcement (GFRPs) applications has increased in recent days. In this study, glass fibre reinforced epoxy composites with different nano metal oxides are developed by compression moulding method and their mechanical properties such as breaking load, elastic limit, plastic range and fracture point are evaluated. The results indicate that the incorporation of nanophase material with glass fibre can improve the properties of composites.

Hide Abstract

This paper described the tensile, thermal, and moisture absorption characteristic of polyvinyl alcohol (PVA) / bengkuang (Pachyrhizuserosus) starch blend films. The film was produced through the solution casting method. Tensile, thermogravimetric analysis and moisture test were studied to determine the tensile strength, thermal stability, and moisture absorption, respectively. The highest tensile strength (TS) was 15.86 ± 0.69 MPa for pure PVA film. This result was higher than bengkuang starch and its blends film. Tensile elongation (TE) decreased as increased bengkuang starch content in PVA. The thermal degradation of PVA film was higher 10°C than bengkuang starch films in range temperature 200-380°C. The addition of bengkuang starch in PVA also increased moisture absorption. The highest moisture absorption was in the bengkuang starch film. This blend film’s tensile, thermal, and moisture properties probably suggested it could be suitable for food packaging.

Hide Abstract

Drillablity derived from term of machinability, which is applied in drilling. In this study, drillability of titanium alloy 6246 has been investigated through observation of two responses of drilled holes quality, i.e. surface roughness and holes roundness. Taguchi L18 Design Experiment-based approach was used to gain an optimum setting of five drilling parameters: coolant, heat treatment variation, depth of drilling, cutting speed and feed rate. The tool used was TiAlN coated carbide drill insert. Minitab 17 was employed for processing the data; analysis of S/N ratio to find effect of each parameter and ANOVA were employed for analysing the significant of each parameter to the surface quality respectively. ANOVA shows that depth of drilling contributes 55% to the roughness, followed by heat treatment (25%), while coolant only affects the roughness quality by 2%. All the 5 parameters chosen in this research has no statistically significant effect to the roundness. The predicted optimum value of surface roughness of between 0.591 µm to 0.803 µm would be achieved when drilling Ti-6246 at a maximum depth of 10 mm, without coolant, cutting speed of 35 m/min and feed rate of 0.08 mm/min on the as received block.

Hide Abstract

In areca empty fruit bunch, fibres are packed strongly with hemicelluloses, lignin and with slight deposition of wax and inorganic elements.  In the work reported, for the extraction of cellulose from the raw areca fibres, formic acid (20% v/v) and hydrogen peroxide (10% v/v) were used and the yield of 65% cellulose was attained.  To know α-cellulose content with crystallinity, XRD diffractions studies were carried and the values were found to be 93% and 71% respectively. FTIR spectral studies confirm the absence of hemicellulose, lignin and wax in the cellulose extracted from areca fibres. The morphological studies provided the evidence for isolated fibres and removal of deposits in the extracted cellulose.

Hide Abstract