001093   VENKATAIAH M, KUMAR T A, RAO K V, KUMAR S A, SIVA I, SUNIL B R (Mechanical Engineering Dep, Koneru Lakshmaiah Education Foundation, Vaddeswaram - 522 502, Email: anubond@gmail.com) : Effect of grain refinement on corrosion rate, mechanical and machining behavior of friction stir processed ZE41 Mg alloy. Trans Indian Inst Met 2019, 72(1), 123–32.

The aim of the present work is to modify the microstructure of ZE41 Mg alloy by friction stir processing (FSP) and to study the influence of microstructure on the corrosion, mechanical and machining behavior. Microstructural observations revealed the prevalence of grain refinement from ≈ 100 to 3.5 lm. The compound present at the grain boundary was observed to have decreased to a great extent after FSP suggesting the formation of supersaturated grains. Hardness measurements indicated increased hardness after FSP which was attributed to grain refinement effect. Tensile tests showed increased yield strength after FSP without altering the percentage of elongation which was due to the grain boundary strengthening. Corrosion performance of FSPed ZE41 was found to be similar compared with ZE41 due to the synergy of grain refinement, decreased amount of secondary phase and development of supersaturated grains. Grain size was observed as significant factor on machining characteristics as observed from improved machinability for FSPed ZE41 during drilling experiments. It was learnt from the current work that the grain-refined supersaturated ZE41 Mg alloy could be produced through FSP with better mechanical and machining behavior without deteriorating the corrosion performance.

10 illus, 3 tables, 23 ref

001075   SAIKUMARAN A, MYTHILI R, SAROJA S, SRIHARI V (Metallurgy and Materials Group, IGCAR, Kalpakkam, Email: rm@igcar.gov.in) : Microstructural characterization of equiatomic CrFeNbNiV alloy. Trans Indian Inst Met 2019, 72(1), 111–21.

This paper presents the results of an experimental study to investigate the structural and microchemical characteristics of an equiatomic CrFeNbNiV alloy. XRD analysis of CrFeNbNiV alloy, revealed a predominant NbCrNi type HCP Laves phase conjoined with two minor tetragonal and BCC phases. Detailed microstructural investigations using electron microscopy techniques also substantiated the presence of the above mentioned phases. The structure of Laves phase in this alloy is determined ab initio for the first time using Precession Electron Diffraction technique which was in agreement with the Rietveld analysis of XRD pattern. The formation of intermetallic Laves phase was understood based on theoretical phase stability and average d- orbital energy level Md value calculations. The alloy in the ‘as cast’ condition exhibited a very high value of hardness (~ 1500 Hv). No change in the microstructure and hardness was observed on annealing at high temperatures even up to 1373 K (1100 ^oC).

12 illus, 3 tables, 44 ref

001078   SHARMA L, CHHIBBER R (Mechanical Engineering Dep, Indian Institute of Technology Jodhpur, Karwar 342011, Rajasthan, Email: rahul_chhibber@iitj.ac.in) : Effect of heat treatment on mechanical properties and corrosion behaviour of API X70 linepipe steel in different environments. Trans Indian Inst Met 2019, 72(1), 93–110.

Linepipe steels find application in oil and gas transportation, pressure vessels, offshore and other engineering parts because of its high strength as well as high ductility. The reason behind the combination of high strength and ductility is the very fine-grained microstructure. In the present work, a heat treatment procedure was used to alter the microstructure of as-received parent metal and to study its effect on the corrosion behaviour of asreceived X70 linepipe steel. One-step austenitizing followed by quenching and subsequent tempering was performed at 300 C, 450 C and 600 C temperatures to alter the microstructure of as-received base metal. To find the corrosion behaviour due to weight loss, as-received steel specimens were exposed in four different environments for 30 days (normal water pH-7, seawater pH-8.2, 5 % NaCl + 10^-2 mol/l sodium thiosulphate pH-3 and 5 % NaCl + 10^-3 mol/l sodium thiosulphate pH-5). Microstructure of different heat-treated samples shows the presence of different phases developed during heat treatment. Macrostructure examination of different immersed specimens reveals the presence of pits on the outer surface. Different pH and concentration of various exposed solutions affect the corrosion behaviour of heat-treated samples. Microhardness and impact strength of heat-treated samples were evaluated.

19 illus, 7 tables, 45 ref

001003   DWIWEDI S K, SRIVASTAVA A K, CHOPKAR M K (Metallurgical Engineering Dep, National Institute of Technology, Raipur, Chhattisgarh, Email: surendra.dwiwedi@opju.ac.in) : Wear study of chicken eggshell-reinforced Al6061 matrix composites. Trans Indian Inst Met 2019, 72(1), 73–84.

The present work deals with conduction of wear test on Al6061/eggshell composites with load, reinforcement and sliding distance as control factors and its regression analysis. Chicken eggshell is one of the most abundant natural waste products generated in large amount by food processing industry due to its everyday consumption. This material is simply disposed in nature thus constituting environmental hazards. Commercial use of eggshells can produce lightweight materials at low cost. Therefore, being complemented with less dense calcium carbonate, it can be used as reinforcement to develop metal matrix composite using stir casting process. Reinforcement is added in the range of 2–10 wt % at an interval of 2 %. Optical microstructural characterization indicated fair distribution of particles in the matrix, and 4 wt% composite exhibited best properties among all. Further addition of particles proved to be detrimental due to increase in porosity and agglomeration of particles. Wear track and debris were examined with scanning electron microscope to explain the wear process. Regression analysis helped in establishing the relationship between the control factors. Reinforcement of eggshell particles improved the wear resistance of matrix significantly as suggested by analysis of variance.

8 illus, 5 tables, 40 ref

001101   YEHIA H M, ELKADY O A, REDA Y, ASHRAF K E (Helwan Univ, Cairo, Egypt, Email: hossamelkeber@techedu.helwan.edu.eg) : Electrochemical surface modification of aluminum sheets prepared by powder metallurgy and casting techniques for printed circuit applications. Trans Indian Inst Met 2019, 72(1), 85–92.

Two series of Al sheets are coated with different thicknesses of copper-deposited film from 10 to 40 lm by the electroplating technique. The first group is the fresh cast Al sheets, and the other is the recycled water-atomized Al powder prepared by the technique of powder metallurgy. Microstructure and phase structure were examined by XRD, optical microscopy and FESEM. Electrical conductivity, thermal conductivity and coefficient of thermal expansion (CTE) were investigated. The XRD showed that only Al and Cu peaks appeared for the cast Al sheet samples, but for the recycled ones other peaks corresponding to Al₂O₃ were also detected. The microstructure indicated that the coated Cu layer had a dendritic structure in a continuous pattern, but for the recycled samples the dendritic structure was not clear but continuous. Both the thermal and electrical conductivities were gradually increased along with the increase in the Cu thickness, while the CTE was decreased.

10 illus, 25 ref

001074   SAHU J N, SASIKUMAR C (Materials Science and Metallurgical Engineering Dep, MANIT, Bhopal, Madhya Pradesh, Email: jogindrasahu@bhel.in) : Evaluation of microstructure due to addition of carbon in Ni– Cr–Mo steel mechanically through surface mechanochemical case carburizing treatment (SMCT). Trans Indian Inst Met 2019, 72(1), 55–63.

Mechanochemical reaction of Fe–C is achieved in Ni–Cr–Mo steel during surface mechanochemical case carburizing treatment (SMCT) at room temperature. Gradient nano-carbide layers are formed in the surface and near surface up to few microns. The Ni–Cr–Mo steel was treated for 15, 30, 45 and 60 min, respectively, to find out the alteration in microstructure. The surface and crosssectional microstructures were investigated by Olympus optical microscope (Japan), 6390-A scanning electron microscope and JEOL F-2100 transmission electron microscope (TEM). It is observed that mechanical alloying of carbon in iron lattice is achieved and surface carbon concentration increased from 0.17 to 0.8 wt% with 1 hour of SMCT operation time. The mechanochemical reaction between Fe and C produces Fe₃C (cementite) in the surface and undersurface up to 500–800 microns along with nanoparticulate on the surface and near surface in 1-hour operation time. It is observed that the carbide cell blocks (CB) and geometrically necessary boundaries (GNB) are produced due to severe plastic deformation created by SMCT operation.

8 illus, 3 tables, 26 ref

001046   NAGUMOTHU R B, THANGAVELU A, NAIR A M, SUKUMARAN A, ANJILIVELIL T (Metallurgical and Materials Engineering Dep, National Institute of Technology, Tiruchirappalli - 620 015, Email: nrb@nitt.edu) : Development of black corrosion-resistant ceramic oxide coatings on AA7075 by plasma electrolytic oxidation. Trans Indian Inst Met 2019, 72(1), 47–53.

Research to achieve dark shade on aluminum surface is a challenge but worthwhile. In this research work, plasma electrolytic oxidation treatment was carried out on the surface of the AA7075 substrate in different combinations of K₂TiF₆, (NH₄)₆Mo₇O₂₄ and Na₂WO₄ containing electrolytes so as to fabricate high-absorption black corrosion-resistant ceramic oxide coatings for spacecraft applications. The effect of three different kinds of electrolytes on thickness, morphology, chemical composition, phase composition, thermal control property and corrosion resistance was investigated. The results showed that sample KTW, PEO treated with K₂TiF₆ and Na₂WO₄, showed the higher thickness of 29.7 lm. Scanning electron microscopy surface morphology study revealed that micropores were less for coating KTW than the other PEOtreated samples. Energy-dispersive spectroscopy elemental composition analysis indicated that molybdenum, titanium and tungsten species were incorporated into the coating structure. Dark black colored KTM sample, PEO treated with K₂TiF₆ and (NH₄)₆Mo₇O₂₄, showed lower absorption value in absorption spectra obtained by UV–Vis spectrophotometer. Potentiodynamic polarization study confirmed that higher thickness, less porous and W element containing PEO-treated sample KTW showed excellent corrosion resistance than the sample treated with K₂TiF₆ (KT) and the sample treated with K₂TiF₆ and (NH₄)₆Mo₇O₂₄ (KTM).

5 illus, 4 tables, 27 ref

001077   SANKAR G S, KARTHIK G M, MOHAMMAD A, KUMAR R, RAM G D J (Metallurgical and Materials Engineering Dep, Indian Institute of Technology Madras, Chennai - 600 036, Email: nikhila166@gmail.com) : Friction welding of electron beam melted γ-TiAl alloy Ti–48Al–2Cr–2Nb. Trans Indian Inst Met 2019, 72(1), 35–46.

In the current work, rotary friction welding of electron beam melted (EBM) γ-TiAl alloy Ti–48Al–2Cr– 2Nb (at%) was investigated. Welding experiments were conducted using cylindrical bars of 12 mm diameter and 70 mm height in as-fabricated and heat treated (1275 C/ 2 h/furnace cooling) conditions. No cracking problems were encountered during friction welding of as-fabricated EBM samples. However, in as-welded condition, the joints did not perform well in tensile tests and failures were observed to invariably occur at the weld interface. Friction welded joints produced in heat treated EBM samples were also found to suffer from the same problem. In both the cases, the weld region showed fine, fully lamellar γ + α₂ microstructure and relatively high hardness. In order to overcome the problem, a post-weld heat treatment (PWHT) was carried out at 1275 C/2 h/furnace cooling. After the PWHT, the weld region showed a more desirable duplex microstructure consisting of equiaxed primary γ and relatively coarser lamellar γ + α₂. The PWHTed joints showed satisfactory tensile properties, and no failures were observed at the weld interface.

18 illus, 4 tables, 22 ref

001005   ELAHI M A, PLAPPER P (Luxembourg Univ, 1359 Luxembourg, Luxembourg, Email: mahdi.amneelahi@uni.lu) : Dissimilar laser micro-welding of nickel wire to CuSn₆ bronze terminal. Trans Indian Inst Met 2019, 72(1), 27–34.

In the present study, the laser welding of wire to flat geometry for miniature electromechanical hybrid components has been investigated. Considering the geometry of parts to be welded and also requirement of mechanical properties, spatial modulation of the laser beam was needed to be implemented to achieve a sound joint. Tensile-shear test and optical microscopy were employed to represent the mechanical properties and melt pool geometry of the joints. All welds were done by power modulation of the laser beam to better control the energy input at several feed rates and three different beam trajectories. Results showed that the shear load of the joint could be controlled by feed rate and the trajectory of the laser beam. Considering the material combination of the study that were nickel and CuSn₆ bronze, which represented solubility in solid state, a joint stronger than base wire metal was achieved by defining a proper spatial modulation and feed rate of the laser beam.

9 illus, 2 tables, 12 ref

001028   KUMAR G, TANVAR H, PRATAP Y, DHAWAN N (Metallurgical and Materials Engineering Dep, Indian Institute of Technology, Uttarakhand - 247 667, Email: ndhawan.fmt@iitr.ac.in) : Thermal and mechanical activation of sericite for recovery of potash values. Trans Indian Inst Met 2019, 72(1), 17–25.

Sericite sample having potash (K₂O) content ~ 9% was evaluated as a source of potash. The mineralogical studies revealed the fine grain structure of sericite containing muscovite, orthoclase, and phlogopite as the major potash bearing phases. The feed sample directly leached in different lixiviants yielded low potash dissolution values. Planetary ball milling was carried out to liberate the potash values from silicate matrix. It was observed that the K-bearing phases were quite stable, with milling action of about 8 h yielded ~ 30% values. The heat treatment of sericite with NaOH resulted in ~ 90% K-dissolution at optimum conditions (60% flux, 600 C, 30 min) with the formation of sodium silicate and kalsilite. Mechanical activation had a positive effect on heat treatment kinetics as temperature decreased from 600 to 250 C with ~ 100% potash recovery. CaCl₂ and Na₂CO₃ were also evaluated as flux and based on a comparison of process variables and yield, NaOH was found to be the best flux.

11 illus, 2 tables, 24 ref

001064   RAJ R, KUMARI A, SAHU D K, PRASAD R, RANGANATHAN S (Metallurgical and Materials Engineering Dep, NIT, Jamshedpur, Jharkhand, Email: aartikumari0809@gmail.com) : Carbothermic reduction of iron oxide waste generated during the processing of ilmenite. Trans Indian Inst Met 2019, 72(1), 11–6.

In India, ilmenite is considered as a major mineral reserve for the extraction of titanium. During the processing of ilmenite to produce titanium dioxide, huge amount of iron oxide is generated and dumped as waste. According to an approximation, 0.7 ton of iron oxide waste is generated for one ton of synthetic rutile production. This waste iron oxide has great potential to be utilized as resource of iron. Therefore, the present work deals with the carbothermic reduction studies of iron oxide waste generated during the ilmenite processing. The spent graphite electrode of electric arc furnace was used as reductant for the reduction studies. Different parameters such as reduction temperature, residence time and weight ratio of iron oxide/reductant were investigated. Reduction studies were carried out by varying the residence time at 15, 30, 60 and 120 min. With an increase in reduction temperature and residence time, percent reduction was found to be increased. Maximum reduction value of 95% was obtained at optimized reduction condition. After reduction, fine powder of metallic iron was obtained, which was characterized by XRD and particle size analyzer. The generated fine powder of metallic iron had direct application and high market value.

6 illus, 17 ref

001002   DIN S H, SHAH M A, SHEIKH N A, BUTT M M (Mechanical Engineering Dep, National Institute of Technology, Srinagar - 190 006, Email: sajad_08phd12@nitsri.net) : CVD Diamond. Trans Indian Inst Met 2019, 72(1), 1–9.

Diamond has the most extreme properties in mechanical, chemical and physical domain. There are many methods to manufacture synthetic diamond. Diamond layers can be deposited on various materials by many processes. The most robust and preferred method is chemical vapour deposition. A variety of researches have been performed on CVD coatings, and a range of developments has come forth starting from initial publications to the latest results. The process parameters of different CVD techniques have been discussed with technical limitations. Flow rate, applied power, increased pressure and temperature range are important parameters for the deposition of CVD diamond.

6 illus, 3 tables, 107 ref

001039   MANGESTIYONO W , MURYANTO S , JAMARI J, BAYUSENO A P (Mechanical Engineering Dep, Diponegoro Univ, 50275, Indonesia, Email: apbayuseno@gmail.com) : Mitigation of CaCo₃ scale formation in pipes under influence of vibration and additives. Rasayan J Chem 2019, 12(1), 192 - 204.

This study aims to mitigate CaCO₃ scale formation in pipes under influence of vibration and oxalic and formic acid additives. The vibration of the pipes was generated mechanically by an electrical motor and controlled by a computer program. CaCO₃ scale was synthesized by CaCl₂ and Na₂CO₃ reagents. The scale deposition was examined at a temperature of 35 °C and vibration frequencies of 0.00, 3.00, and 6.00 Hz. The mass of scale deposit was found as 3.3211 g, 3.8358 g, and 4.4705 g. Fourier Transform Infra Red spectroscopy analysis proved that the additives successfully diffused into the crystal lattice and retarded carbonate anion formation, which consequently retarded the scale formation. In addition, the use of oxalic acid made the morphology of vaterite-changed. However,the formic acid was added, a new habit of hexagonal thin-plate vaterite-could be observed and a fewer carbonate scale was obtained.

6 illus, 3 tables, 43 ref

001091   VANITHA S, VIJAYALAKSHMI P, RAJI P K, PRABA M (Civil Engineering Dep, Sathyabama Institute of Science and Technology, Chennai-600119, (Tamilnadu), Email: vijayalakshmipanneerselvam@yahoo.co.in) : Removal of E.coli from groundwater and surface water by using nylon membrane filtration technique. Rasayan J Chem 2019, 12(1), 32 - 9.

In the present study, a low-cost filter material such as Nylon was used for the disinfection of groundwater poses an excellent bacterial filtration activity against Escherichia coli (gram-negative) cultures. Textile fabrics have gained wide acceptance as a filtration membrane, and various substrates having a pore size in microns such as Nylon, polyester, and cotton have been shown to develop microbial filtration properties. In this study, a simple method to filter bacteria using nylon is presented and the solutions are prepared using Autoclave and Laminar Air Flow Chamber. For checking the bacterial concentration in the underground water, a very small volume of sample was tested by keeping it in shaking Incubator. The results revealed that nylon filters were able to decrease the concentration of E. coli from a groundwater sample, with a higher removal efficiency achieved by using two membranes and a lower efficiency by using a single membrane. This study, therefore, suggests that the Nylon membrane demonstrated antibacterial activity against E. coli. For the disinfection of groundwater, Nylon membrane can be used as a potential alternative cost-effective filter for production of safe drinking water.

8 illus, 4 tables, 15 ref

027185   MAHLA S K, DHIR A, SINGLA V, ROSHA P (Mechanical Engineering Dep, I.K. Gujral Punjab Technical Univ, Hoshiarpur- 146 001, Email: mahla.sunil@gmail.com) : Investigations on environmental emissions characteristics of CI engine fuelled with castor biodiesel blends. J Environ Biol 2018, 39(3), 353-7.

Biodiesel is an attractive fuel option for diesel engines in view of issues related to fossil fuel crisis and environmental degradation. The present study aimed to prepare biodiesel from non-edible grade castor Ricinus communis oil and to evaluate the emission characteristics of castor biodiesel fuelled diesel engine at different engine operating loads. The biodiesel was prepared from non-edible grade castor oil by single step alkaline transesterification process at room temperature.The fuel properties like kinematic viscosity, density, calorific value, flash point, pour point, and cloud point were measured as per ASTM D-6751 specifications.The engine used for experimental work is a single cylinder, four stroke, constant speed, direct injection diesel engine. The engine testing was performed at different engine loads (0.9, 1.8 and 2.7 bmep) and at constant speed of 1500 rpm with different tested fuel blends i.e. B0, B20, B40 and B60. The emission parameters like nitrogen oxides, hydrocarbons and carbon monoxide were evaluated using flue gas analyzer. Production yield of 96.5 % was obtained using biodiesel synthesis and castor oil based biodiesel was found to possess similar fuel properties when compared to fossil petro-diesel. At full engine load condition of 2.7 bmep, the hydrocarbon emission was lowered by 24.6, 39.6 and 42.1 % for B20, B40 and B60 fuels, respectively, and the carbon monoxide emission was reduced by 12.9, 17.1 and 26.2 % for tested fuel blends B20, B40 and B60, respectively, when compared to petro-diesel. At 2.7 bmep load condition, the NOx emissions was higher by 28.2 % for B60 fuel when compared to petro-diesel, while, at 0.9 bmep load condition, NOx emissions increased by 11.8 and 15.1 % for B20 and B40 blends, respectively, when compared with petro-diesel. The non-edible grade of castor oil can be used as a raw material for biodiesel production and its blend with diesel is a suitable fuel candidate for use in diesel engine without modifications, which results in overall low emissions.

2 illus, 2 tables, 20 ref

027180   MAHMOUDINEZHAD M H, KARKHANEH A, JADIDI K (Biomedical Engineering Dep, Amirkabir Univ of Technology (Tehran Polytechnic), Tehran, Iran, Email: a.karkhaneh@aut.ac.ir) : Effect of PEDOT:PSS in tissue engineering composite scaffold on improvement and maintenance of endothelial cell function. J Biosci 2018, 43(2), 307–19.

According to recent research, smart polymers can affect different kind of mammalian cells such as endothelial cells. It is known that conductive polymers have great features, e.g. electrical conductivity, and can help increase electrical cell communication. To clarify the effect of one of these smart materials on endothelial cells, which are not inherently electrically dependent, poly (3, 4-ethylene dioxythiophene) polystyrene sulfonate (PEDOT:PSS) was chosen. Scaffolds were composed of gelatin, alginate, and PEDOT:PSS and made through solvent casting. Human umbilical vein endothelial cells (HUVECs) were cultured on the scaffold with different PEDOT:PSS concentrations. SEM, MTT assay, cell attachment, nitric oxide measurement, real-time PCR and immunohistochemistry analysis were employed to assess endothelial cell responses. Although there was no significant difference in swelling ratio, mass loss, and cell attachment when PEDOT:PSS concentration increased in scaffold construction, cell proliferation noticeably increased after seven days. The cells showed a significant increase in proliferation and NO release to the scaffold with 1 % PEDOT:PSS concentration. The results indicated increases in the amount of expression of platelet endothelial cell adhesion molecule-1 (PECAM-1, CD31), kinase insert domain receptor (KDR), vascular-endothelial Cadherin (VE. Cadherin), and von Will brand factor (vWf) in the group which contained a conductive polymer in comparison with the non-conductive scaffold. Therefore, as a conductive polymer, PEDOT:PSS can affect the endothelial cell behaviours.

12 illus, 1 table, 50 ref

027179   AMBROSE D C P (Central Institute of Agricultural Engineering, Coimbatore, Tamil Nadu, Email: dawncp@yahoo.com) : Effect of packaging on the shelf life of tender palmyra (Borassus flabellifer) fruit endosperm. J Appl & Nat Sci 2018, 10(2), 705 - 9.

Tender palmyra (Borassus flabellifer) fruit endosperm, also known as ice apple is consumed during the summer months especially in Southern and Eastern India. The endosperm is manually removed from the tender palmyra fruit using a heavy knife or sickle by the road side vendors before it is consumed. An investigation on retail film packaging was conducted to study the shelf life of tender palmyra endosperm in sealed packages. The research was carried out to study the effect of packaging films of different thickness on the physio-sensory properties of the endosperm under ambient (32 ± 2 °C) and refrigerated (5 ± 1 °C) conditions. The endosperm was packed in polypropylene bags of 40 and 80 micron thickness and low density polyethylene bags of 150 and 450 micron thickness and High Molecular density (HM) polyethylene bags of 40 micron thickness. The packed samples were kept for storage under ambient and refrigerated conditions. They were evaluated for the changes in weight loss, TSS and also firmness, colour and odour by subjective evaluation at periodic interval during storage. The weight loss was minimum for the sample packed in 450 micron Low Density Polyethylene bag under refrigerated storage. Sensory scores revealed that the overall acceptability (5.0) of palmyra endosperm packed in 450 micron thickness Low Density Poly Ethylene was highest at the end of storage under ambient condition. Similarly, highest overall acceptability (4.0) was observed in High Molecular density polyethylene bag of 40 micron thickness at refrigerated storage. Under normal conditions, palmyra endosperm is prone to spoilage within few hours due to oxidation and fermentation. The results of the study revealed that the shelf life of palmyra endosperm could be extended up to two days under ambient condition, when packed in Low Density Poly Ethylene bag of 450 micron thickness, whereas under refrigerated condition, shelf life could be up to eight days, when packed in high molecular density polyethylene bags of 40 micron thickness.

2 illus, 3 tables, 14 ref

004753   TIWARI N, MOHARANA M K (Mechanical Engineering Dep, National Institute of Technology Rourkela, Rourkela- 769 008, Email: mkmoharana@gmail.com) : Parametric analysis of axial wall conduction in a microtube subjected to two classical thermal boundary conditions. Sadhana 2019, 44(7), 170.

Heat transfer in laminar flow microtube is numerically explored with an objective of discriminating conjugate heat transfer process experienced in a microtube under two different thermal conditions. Two classical thermal conditions – constant heat flux and constant wall temperature – are imposed separately on the outer surface of a microtube. Wide parametric variations are considered in this study, for the two thermal conditions, albeit the problem under consideration being very classical from both geometry and thermal condition point of view. The parametric variations considered in this work include wall thickness, wall conductivity and coolant flow rate. An expression for Nusselt number in terms of radial (or transverse) and axial conduction number is presented and validated against existing theoretical correlation as well as reported experimental data for both circular and non-circular channels. Dominance of axial conduction over radial (or transverse) conduction is explored and it is found that the effect of wall material on conjugate heat transfer plays an important role. Additionally, it is also observed that with the increase in coolant flow rate, the ratio of radial to axial conduction number increases for both thermal boundary conditions.

15 illus, 6 tables, 35 ref

027184   JAWA G K, AHUJA S M (Chemical Engineering Dep, Sant Longowal Institute of Engineering and Technology, Longowal-148 106, Email: jawagulshan@gmail.com) : Removal of Cd(II) from aqueous solution by using Arachis hypogea as low cost biosorbent. Asian J Chem 2018, 30(5), 1078-82.

Present study reports the removal of cadmium(II) removal from aqueous solutions by using Arachis hypogea as abundantly available biomaterial. Kinetic and equilibrium studies have been reported. Effects of various parameters such as pH, stirring speed, initial metal ion concentration, contact time, adsorbent dose have been found in batch experiments in their significant ranges. Freundlich and Langmuir isotherms have been applied to find adsorption behaviour.

7 illus, 2 tables, 37 ref

027183   SARTIKA M, LUBIS M, HARAHAP M B, AFRIDA E, GINTING M H S (Chemical Engineering Dep, Sumatera Utara Univ, Indonesia, Email: maulida@usu.ac.id) : Production of bioplastic from avocado seed starch as matrix and microcrystalline cellulose from sugar palm fibers with Schweizer's reagent as solvent. Asian J Chem 2018, 30(5), 1051-6.

The mechanical properties of bioplastic prepared from avocado seed starch and mycrocrystalline cellulose from sugar palm fibers as filler using Schweizer’s reagent as solvent was studied. Bioplastics were prepared from avocado seed starch and reinforced with microcrystalline cellulose (MCC) from sugar palm fibers with composition ratio were 7:3, 8:2 and 9:1 (w/w) and using glycerol as plasticizer with variation of 0.1; 0.2; 0.3 and 0.4 (v/w of starch). Microcrystalline cellulose dissolved in the copper solution (Schweizer reagent) with ratio of MCC:copper solution is 1:10. Degree of crystallinity of microcrystalline cellulose was 97.5 %. Morphological analysis showed that the isolated microcrystalline cellulose from sugar palm fibers are rod-like shape with diameter of 5.55-9.44 μm and crystallite size of 25.08 nm. Mechanical properties of bioplastic showed that the best condition of bioplastics obtained at comparison of mass starch microcrystalline cellulose 7:3 and the addition of glycerol 0.1 (v/w) for tensile strength 20.874 MPa and elongation at break of 6.22 %.

5 illus, 1 table, 40 ref

027182   TASLIM, MIRNANDAULIA M, IRIANY, TAMBUN R (Chemical Engineering Dep, Sumatera Utara Univ, Medan-20155, Indonesia, Email: taslim_hr@yahoo.co.id) : Furfural production from mile-a-minute weed (Mikania micrantha) using organic acid from bilimbi (Averrhoa bilimbi). Asian J Chem 2018, 30(5), 1007-11.

Mile-a-minute weed (Mikania micrantha) is an invasive weed with rampant growth which seriously damages the ecosystem. One promising way to control mile-a-minute weed by utilizing it for furfural production because waste of mile-a-minute weed contains a lot of pentosane.In this work, fufural synthesized by using bilimbi (Averrhoa bilimbi) which is an organic acid and environmentally friendly. In this study,mile-a-minute weed (100-70 mesh size), bilimbi acid and salt (NaCl) were reacted in a three neck round bottom flask at 80-140 ºC for 120-330 min. The weight (mile-a-minute weed) to volume (bilimbi acid) ratio was set to be 1:6 at fixed solution volume of 750 mL. Furfural was extracted from water using solvent extraction method employing chloroform as a solvent. After extraction the lower layer would contain furfural and chloroform while the upper layer would contain water. Furfural was purified by evaporating chloroform. The furfural was identified by the acetic aniline colour reaction, infra red spectrophotometer and GC-MS. The highest furfural yield was obtained at 7.2 % for the reation temperature of 100 ºC and reaction time of 300 min.

4 illus, 1 table, 51 ref

027181   HASHEMI G, MIRHEIDARI S P, SANTIVANEZ C G D (Civil and Environmental Engineering Dep, Polytechnic Univ of Milan, Italy, Email: gholamreza.hashemi@mail.polimi.it) : Urbanization impact on the water and food security and assessment of wheat production and its irrigation water requirements using CROPWAT model in Iran: A case study of City Tehran. Asian J Adv Basic Sci 2018, 6(1), 7-15.

In the modern world, the equal allocation of amenities amongst the society individuals has been affected by the phenomena of Urbanization and urban development. Tehran, the capital of Iran, is always the main destination of migrants from all over the country because of its dominant modernistic urban attractions. The latest official national census in 2006 showed that during 1921 to 2006, in the last 85 years, Tehran’s population has multiplied by 37 and its area has multiplied by 100. This rapid Urbanization has replaced a huge area of agricultural land, fertile arable land. in addition, Tehran total water consumption with an average annual growth rate of 23.1 percent reached to more than 990 million cubic meters in 2008 which all of these elements emphasis on a much more sustainable consumption pattern requirement and more attention to the Tehran’s water and food security. For instance, in this research for the first time indicated that the domestic production of wheat in Tehran city just covers 6 % of Tehran’s population wheat requirement while it consumes 25 % of water consumption of Tehran city.

11 illus, 55 ref

028568   RAO H J, KING P, KUMAR Y P (Chemical Engineering Dep, GMR Instt of Technology, Rajam- 532 127, Email: jogarao.h@gmrit.org) : Equilibrium isotherm, kinetic modeling, and characterization studies of cadmium adsorption in an aqueous solution by activated carbon prepared from Bauhinia purpurea leaves. Rasayan J Chem 2018, 11(3), 1376 -92.

Cadmium is the toxic metal selected for adsorption in this study and adsorbent of interest was activated carbons prepared from Bauhinia purpurea leaves as a plant biomass. Batch experimental studies conducted for the given adsorbent imparted that the experimental data were fitted very well with the Freundlich isotherm for the Cadmium adsorption process. The sorption kinetic studies for a given adsorbent indicated that the adsorption tends to follow the pseudo-second order. The suitability of kinetic models followed in the order by Second - order kinetic model > First - order model >Elovich model > Intra-particle diffusion model.The mean adsorption energy E value of Cadmium adsorption was decreased with increasing isothermal temperature (303–323K) from 1.936 to 1.79 kJ/mole. It was observed that the scope of an ordinary free energy credited to physical adsorption and the force of attraction between the adsorbate and adsorbent is very weak, therefore this type of adsorption can be easily reversed by heating or by decreasing the pressure. The characterization of metal-adsorbent interactions before and after adsorption was studied using SEM, FTIR and XRD techniques. FTIR spectrum of raw activated carbon of Bauhinia purpurea leaves reveals that there were a large number of hydroxyl and carboxyl groups present on the surface of the adsorbent, which possibly reacted with metal ions in aqueous solution.

12 illus, 6 tables, 31 ref

028553   JOTHIBASU S, MOHANAMURUGAN S, VINOD A (Mechanical Engineering Dep, Aarupadai Veedu Institute of Technology, Chennai, Email: drsmm14@gmail.com) : Influence of chemical treatments on the mechanical characteristics of Areca sheath-Flax fibres based epoxy composites. Rasayan J Chem 2018, 11(3), 1255-62.

In the present work, Areca Sheath and Flax fibres were selected as reinforcements. The selected fibres were treated with chemicals namely Hydrochloric acid, Sodium Hydroxide, and Benzyl Chloride. Four different composites were developed using the hand lay-up process, three composites based on treated fibres and one composite with untreated fibres for comparison. Fourier-transform infrared spectroscopy analysis was done to study the functional groups present in the fibres. The developed composites were characterized for its mechanical characteristics namely tensile, flexural, impact and hardness as per ASTM. The tested composites were analysed for its morphological characteristics using Scanning Electron Microscopy. From the results, it was found that sodium hydroxide treatment to fibres was beneficial to improve its mechanical property when compared to the other composites.

8 illus, 1 table, 21 ref

028569   RIFKI S, AHMAD N, ENENG M, SUHANDA S, SUNENDAR P B (Engineering Physics Dep, Institut Teknologi Bandung, Indonesia, Email: rifkiseptawendar@gmail.com) : Synthesis of zirconia 1-D nanomaterials from local zircon-based Zr(OH)₄ mediated by PEG-6000. Res J Chem Environ 2018, 22(2), 163-71.

Zirconia 1-D nanomaterials are promising materials that demonstrate extraordinary and unique properties that can be applied in many great fields such as electronic, medical and chemical. The present study reports the synthesis of zirconia 1-D nanomaterials from local zircon-based zirconium hydroxide hydrates mediated with polyethylene glycol 6000 as a structuredirecting template. The synthesis was carried out by an aging ultrasonic method at various PEG/Zr mole ratios from 0.067 to 0.167, at pH 9, at a temperature of 80°C and with aging periods for 1-3 hours. Thermogravimetric and Differential Thermal Analysis (TG-DTA) were conducted to identify the thermal behavior of the as-synthesized zirconia and an X-ray diffraction study was used to characterize the mineralogy of the zirconia. Meanwhile, scanning and transmission electron microscopes were used to observe the morphology of the synthesized zirconia. It was found that the crystallization of zirconia occurred at a temperature of approximately 810 °C. However, zirconia 1-D nanomaterials were obtained at a PEG/Zr mole ratio of 0.167 with an aging period of 2 hours and at a calcination temperature of 900°C. The calcined zirconia exhibits good crystallinity and consists of 64.2 % and 35.8 % of tetragonal and monoclinic phases respectively with the average crystal sizes of less than 20 nm. Besides, the ZrO₂ shows 1-D morphologies such as nanorod-like shapes with aspect ratios of 4-12, nanobar-like shapes and elongated agglomerates.

7 illus, 1 table, 26 ref

028545   EKO A, ROB B (Chemical Engineering Dep, Politeknik Negeri Bandung, Indonesia, Email: andrijanto.2002@gmail.com) : The effect of calcination temperature of sulfated zirconia catalyst for simultaneous reactions in biodiesel production. Res J Chem Environ 2018, 22(2), 157-62.

The activity of sulfated zirconia catalyst for simultaneous esterification of free fatty acid and transesterification of triglyceride was studied. Oleic acid (free fatty acid) and tributyrin (triglyceride) were used as model compounds respectively. Mixtures of free fatty acids and triglycerides are typical biodiesel feedstock in low grade oils such as animal fats and used cooking oils. The effect of calcination temperature of synthesized sulfated zirconia catalyst XZO-01 on its activity was investigated. The activity of the synthesized sulfated zirconia XZO-01 and commercial sulfated zirconia XZO-1720 was compared. The optimum calcination temperature for the sulfated zirconia XZO- 01 was found to be 600^oC for both reactions. The results reveal that the synthesized sulfated zirconia catalyzes both esterification and transesterification reactions simultaneously. This catalyst is promising used as solid acid catalyst for biodiesel production using low grade oils as starting material. The simultaneous reactions were performed in pressurized reactor at 120^oC. Characterization by X-ray diffraction and total BET surface area allowed to correlate the crystal structure and surface area was changes with calcination temperature and the effect on its activity.

10 illus, 2 tables, 18 ref

028581   UFAFA A, CANDRA S N (Chemical Engineering Dep, Internasional Semen Indonesia Univ, Indonesia, Email: ufafa.anggarini@uisi.ac.id) : Investigating alumina silicate source in geopolymer compressive strength: Surface morphology and crystal phase study. Res J Chem Environ 2018, 22(2), 129-33.

In this present study, geopolymer, which is a cementitious specimen was synthesized with Fly and Bottom Ash to form aluminosilicate source. The geopolymer was synthesized by sol gel method at SiO₂/Al₂O₃ ratio of 4. The percentage of SiO₂ weight in fly ash was higher than bottom ash which was about 31.96 wt % and 21.07 wt % for each material. The Al₂O₃ content in fly ash also has a higher value than bottom ash at 22,62 wt% and 5.92 wt %, respectively. In order to study the surface morphology and X-ray Diffraction (XRD) for crystal phase analysis, the characteristics of Geopolymer from fly ash and bottom ash were compared using the Scanning Electron Microscope (SEM). The diffractogram result showed that geopolymer that synthesized from fly ash has a higher amorphous phase than bottom ash geopolymer, which indicated that fly ash geopolymer is not only more reactive than bottom ash geopolymer, it also has an impact on good polymerization processes. This result is parallel with the SEM result that shows fly ash geopolymer has less unreacted particle than bottom ash geopolymer. It was found that reactive SiO₂ and Al₂O₃ in fly ash produced geopolymer with a high compressive strength of 68 Mpa while bottom ash produced geopolymer with the compressive strength of 51 Mpa.

3 illus, 2 tables, 15 ref

029685   MEETEI T S, BOOMADEVI S, PANDIYAN K (SASTRA Deemed Univ, Thanjavur - 613 401, Email: krishpandiyan@ece.sastra.edu) : Design and development of low-cost room temperature electric field poling system for the fabrication of quasi-phase matching devices. Pramana - J Phys 2018, 91(3), 37.

We discuss the construction of a low-cost room-temperature electric field poling system and the fabrication of high-quality periodically poled lithium niobate (PPLN) devices. The various poling parameters of the indigenously developed quasi-phase matching (QPM) fabrication facility are studied and optimised for the wastage-/breakage-free device fabrication. Furthermore, we present a simple way to monitor the domain reversal process in the poling system using a crossed polariser arrangement. It has been observed that the pulse-by-pulse poling process is more favourable for monitoring the domain reversal and for estimating the exact poling pulse required for the fabrication of (1 : 1) duty cycle PPLN devices. In addition to the fabrication of PPLN, we further discuss the quality checking of the fabricated devices using a simple far-field diffraction experiment.

14 illus, 1 table, 47 ref

029691   SINGH J P, RAJAGOPAL K, ROY B K (Electrical Engineering Dep, National Institute of Technology, Silchar - 788 010, Email: jayprakash1261@gmail.com) : A new 5D hyperchaotic system with stable equilibrium point, transient chaotic behaviour and its fractional-order form. Pramana - J Phys 2018, 91(3), 33.

Hidden attractors with the family of stable equilibrium points in higher-dimensional systems are more interesting and difficult discover compared to other families of hidden attractors. In this paper, a new 5D hyperchaotic system is reported. The proposed system has only one stable equilibrium point. Hence, the new system belongs to the category of hidden attractors. Although some lower-dimensional chaotic systems with stable equilibrium points are available in the literature, but very few hyperchaotic systems with stable equilibrium points are reported. The new system is simple considering the number of terms, compared with the existing similar type of systems. The proposed system exhibits multistability and transient chaotic behaviour. The fractional-order counterpart of the proposed system is analysed using Adams–Bashforth–Moulton algorithm and the chaotic nature is validated by bifurcation diagram. The simulation results confirm the claims made in the paper.

14 illus, 1 table, 65 ref

029916   SOLEJA N, MANZOOR O, KHAN I, AHMAD A, MOHSIN M (Biosciences Dep, Jamia Millia Islamia, New Delhi - 110 025, Email: mmohsin1@jmi.ac.in) : Role of green fluorescent proteins and their variants in development of FRET-based sensors. J Biosci 2018, 43(4), 763–84.

Since the last decade, a lot of advancement has been made to understand biological processes involving complex intracellular pathways. The major challenge faced was monitoring and trafficking of metabolites in real time. Although a range of quantitative and imaging techniques have been developed so far, the discovery of green fluorescent proteins (GFPs) has revolutionized the advancement in the field of metabolomics. GFPs and their variants have enabled researchers to ‘paint’ a wide range of biological molecules. Fluorescence resonance energy transfer (FRET)-based genetically encoded sensors is a promising technology to decipher the real-time monitoring of the cellular events inside living cells. GFPs and their variants, due to their intrinsic fluorescence properties, are extensively being used nowadays in cell-based assays. This review focuses on structure and function of GFP and its derivatives, mechanism emission and their use in the development of FRET-based sensors for metabolites.

12 illus, 3 tables, 102 ref

029690   ROY N, SHIULY A, SAHU R B, JAKKA R S (Earthquake Engineering Dep, IT Roorkee, Roorkee, Email: rsjakka@gmail.com) : Effect of uncertainty in VS−N correlations on seismic site response analysis. J Earth Syst Sci 2018, 127(7), 103.

This paper studies the reliability of the calculated shear-wave velocity (VS) from different available VS and SPT-N correlations in terms of seismic site response analysis. In the present study, various VS–N correlations developed for different regions around the globe have been used to calculate the bound of VS variations with depth at three different sites in Kolkata city. This bound has later been used to generate the random VS profiles using the Monte Carlo simulation. Equivalent linear site response analysis has been performed to study the response of those generated profiles under different input motion excitations. Strong-to-weak ground motion records have been used for this purpose. The amplification spectra of the generated VS profiles using all soil types and specific soil-type VS–N correlations show significant variations. The study also shows that the VS–N correlation may result in quite different VS,30 values and subsequently it may lead to the different site classes according to the NEHRP 2003 classification. So, the random choice of the VS–N correlation, where the direct measurement of VS is not available, may affect the outcome of seismic hazard analysis significantly. The study points out the need for accurate estimation of the VS profile either from in-situ determination or using site-specific correlation.

14 illus, 1 table, 63 ref.

029683   KUTNIS M, ULUTAS H, ISIK E (Civil Engineering Dep, Bitlis Eren Univ, Bitlis- 13100, Turkey, Email: ercanbitliseren@gmail.com) : PSHA of Van province for performance assessment using spectrally matched strong ground motion records. J Earth Syst Sci 2018, 127(7), 99.

Within the framework of the performance based earthquake engineering, site specific earthquake spectra for Van province has been obtained. It is noteworthy that, in probabilistic seismic hazard assessment, as a first stage data from geological studies and records from the instrumental period were compiled to make a seismic source characterization for the study region. The probabilistic seismic hazard curves were developed based on selected appropriate attenuation relationships, at rock sites, with a probability of exceedance 2, 10 and 50 % in 50 yrs period. The obtained results are compared with the spectral responses proposed for seismic evaluation and retrofit of building structure in Turkish Earthquake Code (2007), section 7. The acceleration response spectrums obtained from probabilistic seismic hazard analysis are matched to adjust earthquake accelerograms recorded during the 2011 Van earthquakes by using SeismoMatch v2.0 software. The aim of this procedure is to obtain a set of reasonable earthquake input motions for the seismic evaluation of existing buildings.

13 illus, 38 ref

031063   KUNTE A A, GAIKWAD A N (Electronics and Telecommunication Dep, Sinhgad Coll of Engineering, Pune - 411 041, Email: anaghakunte7@gmail.com) : Dielectric constant measurement of low loss liquids using stacked multi ring resonator. Sadhana 2018, 43(12), 212.

The concept of dielectric constant measurement has been extended and applied in agriculture, pharmaceutical and food industry for quality control of liquids. Dielectric analysis of material at microwave frequencies can be done using novel shielded stacked multi-ring resonator (SMRR). The dielectric constant of liquids and paste has been calculated using SMRR with greater accuracy than the planar resonator, boxed resonator and stacked resonator. SMRR contains a ring resonator with fed patch and parasitic patch with different numbers and sizes of rings. The dimensions of rings on the parasitic patch are optimized to achieve Quality factor Q greater than 100 and return loss less than -2 dB. Due to dual resonance in novel SMRR, structure losses are reduced by 50 % than planar resonator structure. The behavior of SMRR structure at the 2.45 GHz frequency is studied with E field and H field. 3D model is designed in Computer Simulation Technology Microwave Studio (CST MWS) using TLM (Transmission Line Modeling) solver. Electromagnetic field analysis as well as impedance bandwidth of SMRR using CST MWS 3D model prove that electromagnetic coupling in SMRR structure increases thus improves quality factor. In SMRR quality factor increases and losses reduce help us to predict the complex permittivity of material for quality analysis.

16 illus, 9 tables, 35 ref

031081   SURABHI K M, REDDY J V R, SRIKANTH D (Applied Mathematics Dep, Defence Institute of Advanced Technology (Deemed Univ), Pune - 411 025, Email: sri_dasari1977@yahoo.co.in) : Impact of temperature and concentration dispersion on the physiology of blood nanofluid: Links to atherosclerosis. Sadhana 2018, 43(12), 210.

A theoretical model of blood-silver nanofluid flow through an x-shaped tapered stenotic artery in the presence of a catheter is understood in detail. The rheology of the blood is considered as that of a micro-polar fluid. Suspension of the silver nano-particles in the micro-polar fluid is proposed to investigate the temperature and concentration dispersion from the immersed temperature-sensitive drug-coated nano-particles. The effects of velocity discontinuity at the arterial wall in the stenotic and non-stenotic regions are considered. The outer surface of the catheter is layered with the temperature-sensitive, drug-coated nano-particles. The resulting mathematical formulation involving the coupled non-linear momentum, temperature and concentration equations is solved using the Homotopy Perturbation Method. The efficiency and convergence of the method to the modelled equations are discussed in detail. The consequent effects of the fluid and geometric parameters on pressure drop, flow rate, impedance and wall shear stress of the fluid flow are computed. It is noticed that the high volume fraction of the nano-particles in the blood results in high flow velocity, contributing to secondary flow regions, thus resulting in higher shear stress. Such high volume fraction of the nano-particle may lead to the pathological disorder called aneurysm. This physical model has an important application of drug delivery in biomedical and pharmaceutical industry to prevent obstructions in arteries. Further, the results obtained could be very useful in the manufacturing of related artificial devices.

20 illus, 4 tables, 41 ref

031072   PODDER B, BANERJEE P, KUMAR K R, HUI N B (National Institute of Technology (NIT), Durgapur, Email: nirmal.hui@me.nitdgp.ac.in) : Flow forming of thin-walled precision shells. Sadhana 2018, 43(12), 208.

Flow forming is an innovative form of cold and chipless metal forming process, used for the production of high precision, thin-walled, net-shaped cylindrical components. During this process, the length of a thick walled tube, commonly known as a preform, is increased with a simultaneous decrease in the thickness of the preform without any change in the internal diameter. Forming of the preform is carried out with the help of one or more rollers over a rotating mandrel. By a pre-determined amount of thickness reduction in one or more number of forming passes, the work material is plastically deformed in the radial direction by compression and made to flow in an axial direction. The desired geometry of the workpiece is achieved when the outer diameter and the wall of the preform are decreased, and the available material volume is forced to flow longitudinally over the mandrel. Over the last three and a half decades the flow forming technology has undergone several remarkable advancements. The versatility of the process makes it possible to produce a wide variety of axisymmetric, nearer to the net-shape tubular parts with a complex profile using minimum tooling changes. In this review article, process details of flow forming have been elaborated. The current state-of-the-art process has been described, and future developments regarding research and industrial applications are also reviewed.

14 illus, 6 tables, 77 ref

031085   ZHENG D, QIU J, WEI C, CHENG L, ZHU K (Hohai Univ, Nanjing 210098, China, Email: 121267184@qq.com) : An experimental GPR detection study of environmentally-influenced structural defects in hydraulic engineering. Sadhana 2018, 43(12), 207.

Structural defects such as separation between concrete slab and foundation, and structural voids often occur in hydraulic engineering, which threatens the safety of hydraulic engineering. As the size and internal material of the hydraulic engineering can be queried, ground penetration radar (GPR) detection has the advantage to detect these defects when compared with other nondestructive detection methods. At the same time, when GPR detection is applied to defect these structural defects in hydraulic engineering, complex environmental factors including the uneven structural surface, clutter interference, water reflection, etc. have to be taken into account. In this work, two experimental models are designed to represent two different types of hydraulic structures and the structural defects including separation between concrete slab and its bottom material and void or hole defects are simulated on the two test models, respectively. Through the GPR detection on the two experimental models, the effects of the three environmental factors on the radar images and the signatures of the radar images under the influence of the three environmental factors are studied. Then, different image processing methods are adopted to reduce the influence of the three different environmental factors, and the effects of these methods are verified using the radar images obtained from the experiments. Finally, the GPR detection on a practical hydraulic engineering influenced by the environmental factors and the image processing methods are investigated, which successfully verify the experimental investigation results. It is expected that this study would provide significant technology support for structural defects detection in hydraulic engineering.

17 illus, 4 tables, 21 ref

031060   HOSSEINI S M R, NAEINI S A, HASSANLOURAD M (Civil Engineering Dep, Imam Khomeini International Univ, Qazvin, Iran, Email: Naeini_h@ikiu.ac.ir) : Pre- and post-cyclic behaviour of an unsaturated clayey soil contaminated with crude oil. Sadhana 2018, 43(12), 204.

Besides adverse impacts on the environment, pollution with hydrocarbon compounds such as crude oil affects the geotechnical parameters like deformation modulus and shear strength. The present research involves evaluation of clayey soil properties changes in an unsaturated state due to application of cyclic loads before and after contamination with crude oil. A series of constant water content (CW) static and dynamic triaxial tests were conducted on samples that were compacted to the same dry density but different degrees of saturation and net confining pressures. The soil studied was provided from a place near an oil refinery located in Iran’s capital city and was artificially polluted with 3 %, 6 % and 9 % crude oil. Deformation modulus reduction due to cyclic loads application was considerably more than reduction of shear strength. Also, these parameters increased due to increasing net confining pressure and initial matric suction. Several chemical tests and techniques were employed to investigate the chemical variations in soil structure and the role of different chemical components of crude oil on quantitative variations of soil characteristics.

12 illus, 4 tables, 32 ref

031051   BISWAL S K, MOHARANA M K, AGRAWAL A K (Civil Engineering Dep, National Institute of Technology Agartala, Tripura - 799 046, Email: drsushantbiswal@gmail.com) : Effects of initial stage of dam-break flows on sediment transport. Sadhana 2018, 43(12), 203.

Experimental and numerical studies of dam-break flows over sediment bed under dry and wet downstream conditions are investigated and their effects on sediment transport and bed change on flow are illustrated. Dam-break waves are generated by suddenly lifting a gate inside the flume for three different upstream reservoir heads. The flow characteristics are detected by employing simple and economical measuring technique. The numerical model solves the two-dimensional Reynolds-Averaged Navier–Stokes (RANS) equations with k-e turbulence closure using the explicit finite volume method on adaptive, non-staggered grid. The model is validated with laboratory data and is extended for simulating non-equilibrium sediment transport and bed evolution process. The volume of fluid technique is used to track the evolution of the free surface, satisfying the advection equation. The comparison study reveals that the current model is capable of defining the dam-break flow and improves the accuracy of determining morphological changes at the initial stages of the dam-break flow. A good agreement between the model solutions and the experimental data is observed.

8 illus, 2 tables, 46 ref

031077   SELVI C, SIVASANKAR E (Computer Science and Engineering Dep, National Institute of Technology, Tiruchirappalli - 620 015, Email: selvichandran.it@gmail.com) : A novel similarity measure towards effective recommendation using Matusita coefficient for Collaborative Filtering in a sparse dataset. Sadhana 2018, 43(12), 202.

Collaborative Filtering (CF) is a prominent approach to ensure personalized recommendations to active online users. An efficient CF is the memory-based strategy that finds nearest neighbours to an active user using conventional similarity measures. Most such measures deal with a co-rated item rated by a pair of users and hence they are not appropriate to provide an effective recommendation to a sparse dataset having less corated items. This study proposes a novel similarity measure, Matusita coefficient in CF (MCF), which considers all ratings given by a user to estimate nearest neighbours. MCF considers local and global rating information provided by users on different rating scales. The performance of the proposed measure is examined and checked by comparing it to conventional measures using popular benchmark datasets like MovieLens and Netflix. The recommendation results demonstrate that the proposed measure outperforms conventional similarity measures on various performance metrics like Mean Absolute Error, Root Mean Squared Error, accuracy, precision, recall and coverage.

3 illus, 5 tables, 36 ref

031062   KANCHANADEVI A, RAMANJANEYULU K, SASMAL S, SRINIVAS V (CSIR-Structural Engineering Research Centre, Chennai - 600 113, Email: kanchana@serc.res.in) : Seismic performance evaluation of GLD beam-column sub-assemblages of three different scenarios. Sadhana 2018, 43(12), 201.

Gravity load designed (GLD) structures exhibit poor seismic performance due to inadequate reinforcement to cater for the seismic forces, lack of confinement, poor joint strength, improper anchorage, presence of weak column and strong beams. These structures are also susceptible to environmental impact leading to corrosion of reinforcement which would further degrade their seismic performance. In RC structures, beam–column joints are crucial members and dissipate the seismic energy imparted to the structure. Hence in this study, two typical cases of GLD (i) uncorroded GLD and (ii) corrosion affected GLD (corroded) exterior beam–column sub-assemblages subjected to reverse cyclic loading are investigated and compared. Reinforcement corrosion of one of the GLD specimens is accelerated by the impressed current technique. Based on the investigation on uncorroded GLD and corrosion affected GLD beam–column specimens, it is noted that the corrosion has significant effect on the seismic performance in terms of loss of energy dissipation, strength- and stiffness- degradation. To improve the seismic performance of uncorroded GLD specimens, a low invasive single steel haunch upgradation scheme (SHUS) is proposed in this study. The maximum load carried by steel haunch upgraded GLD specimen is about 30 % higher than that of GLD specimen. Hence, it is noted that by implementing the proposed upgradation scheme for GLD beam–column sub-assemblage, remarkable improvement in the seismic response can be achieved. The present study provides insight into the behaviour of steel haunch upgraded GLD specimen and would also pave the way for formulating seismic upgradation of even corroded GLD beam–column sub-assemblage.

14 illus, 27 ref

031050   ANOOP K P, PANICKER V V, NARAYANAN M, KUMAR C T S (Mechanical Engineering Dep, National Institute of Technology Calicut, Calicut, Email: kpanoop05@gmail.com) : A mathematical model and solution methods for rail freight transportation planning in an Indian food grain supply chain. Sadhana 2018, 43(12), 200.

This paper addresses the rail transportation of food grains undertaken by Food Corporation of India (FCI) to meet the requirements of the food security programme called Public Distribution System (PDS). The research focuses on improving the allocation of railway rakes transporting food grains to a set of storage warehouses. A penalty factor based approach is adopted to represent the considerations in transportation planning and three penalty factors such as rake penalty factor, weekly penalty factor and capacity utilization penalty factor are introduced for the purpose. The single source - multiple destination problem is formulated and solved using exact method to minimize the sum of these three penalty factor values, termed total penalty. Further, a heuristic named optimum rake allocation algorithm is developed and tested using a set of 35 problem instances. The proposed heuristic is found to be highly efficient in terms of solution quality and computation time. A case study of FCI Kerala Region is also carried out to validate the formulated model and the proposed heuristic. The work provides valuable insights into the practical issues encountered in rail freight transportation planning and proposes an effective solution methodology to address them.

4 illus, 13 tables, 20 ref

031055   DELICE Y, AYDOGAN E K, SOYLEMEZ I, OZCAN U (Industrial Engineering Dep, Erciyes Univ, Kayseri, Turkey, Email: ekaydogan@erciyes.edu.tr) : An ant colony optimisation algorithm for balancing two-sided U-type assembly lines with sequence-dependent set-up times. Sadhana 2018, 43(12), 199.

Some practical arrangements in assembly lines necessitate set-up times between consecutive tasks. To create more realistic models of operations, set-up times must be considered. In this study, a sequencedependent set-up times approach for two-sided u-type assembly line (TUAL) structures is proposed for the first time. Previous studies on TUAL have not included set-up times in their analyses. Furthermore, an algorithm based on the Ant Colony Optimization (ACO) algorithm, which is using a heuristic priority rule based procedure has been proposed in order to solve this new approach. In this paper, we look at the sequence-dependent set-up times between consecutive tasks and consecutive cycles, called the ‘‘forward set-up time’’ and the ‘‘backward set-up time’’, respectively. Additionally, we examine the ‘‘crossover set-up time’’, which arises from a new sequence of tasks in a crossover station. In order to model more realistic assembly line configurations, it is necessary to include sequence-dependent set-up times when computing all of the operational times such as task starting times and finishing times as well as the total workstation time. In this study, the proposed approach aims to minimize the number of mated-stations as the primary objective and to minimize the number of total workstations as a secondary objective. In order to evaluate the efficiency of the proposed algorithm, a computational study is performed. As can be seen from the experimental results the proposed approach finds promising results for all literature-test problems.

6 illus, 4 tables, 61 ref

031083   VIJAY M, INDUMATHI G (Pandian Saraswathi Yadav Engineering Coll, Madurai, Email: vijaym1888@gmail.com) : GwPeSOA-based MSVNN: the multimodal biometric system for futuristic security applications. Sadhana 2018, 43(12), 198.

Biometric systems have gained considerable significance as they are highly employed in the security applications. Achieving human recognition is easier and cheaper and the single modality employed for the recognition faces a lot of challenges due to the environmental factors. Thus, the paper proposes a multimodal recognition system based on the Multi-Support Vector Neural Network (MSVNN). The algorithm proposed is the Glowworm Penguin Search Optimization Algorithm (GwPeSOA), which is a modification of the Glowworm Optimization Algorithm (GOA) with the Penguin Search Optimization Algorithm (PeSOA). The proposed method employs two modalities: the ear and the finger vein modalities; the features of the ear image are obtained using the proposed BiComp masking method of feature extraction, whereas the features from the finger vein are extracted using the Repeated Line Tracking (RLT) method. The features obtained are applied to the MSVNN classifier to recognize the person with good accuracy and the proposed BiComp Mask offers robust features for the extraction. The experimentation using the proposed method attained a better accuracy, specificity and sensitivity at a rate of 0.95, 0.95 and 0.9868, respectively.

9 illus, 1 table, 40 ref

031065   LEZGY-NAZARGAH M, EMAMIAN S A, AGHASIZADEH E, KHANI M (Hakim Sabzevari Univ, Sabzevar, Iran, Email: m.lezgy@hsu.ac.ir) : Predicting the mechanical properties of ordinary concrete and nano-silica concrete using micromechanical methods. Sadhana 2018, 43(12), 196.

By combining several materials with specific mechanical properties, new materials with unknown mechanical properties are obtained. Various experiments are required to determine the mechanical properties of the produced composite materials. Since conducting experiment processes is costly and time-consuming, comprehensive studies have been conducted in recent years to solve the problem. Fortunately, it is possible to easily predict the mechanical properties of composite materials without the need to construct them, by inspecting their constituent’s properties using micromechanical methods. Although various micromechanical methods have been presented so far, few of them yielded precise predictions of the properties of composite materials. Therefore, selecting a method suitable to predict the properties of composite materials is of much importance. In this study, some micromechanical approaches, including Hirsch, Hansen, Bache, Cavento, Mori–Tanaka, Eshelby, self-consistent, effective interface and double-inclusion models, were employed for the estimation of elasticity modulus and Poisson’s ratio of ordinary and nanomaterial concretes. The results obtained from the micromechanical methods were compared to those obtained from experimental tests. The obtained numerical results showed that Bache’s model is the most accurate micromechanics model for predicting the elastic mechanical properties of ordinary and nanomaterial concretes.

7 tables, 36 ref

031054   DARABADI B K, KHIAVI A K, OURIA A, RASOULI R (Civil Engineering Dep, Moghadas Ardabili Institute of Higher Education, Ardabil, Iran, Email: babak.msi@gmail.com) : Evaluation of the compactness of subbase and base geomaterials by using stiffness. Sadhana 2018, 43(12), 195.

Stiffness of soil that is defined as ratio of load to deflection depends on some physical properties such as compactness and water content. The purpose of this research study is to use stiffness for estimating compactness of granular geomaterials that are used as subbase and base courses of roads. In this research study, the stiffness of soil samples was determined according ASTM D6758-08 test method by using electro-mechanical device. The dry density of the compacted soil was determined by sand-cone method in the field. More than 80 laboratory and in situ tests were performed. The obtained stiffness data was used to establish a relationship between stiffness, compaction ratio and water content. The results showed that there is a strong relationship between the stiffness, compaction ratio and water content. Also, the result of validation showed that there is good correlation between in situ and laboratory tests results.

6 illus, 3 tables, 20 ref

031076   REDDY S A N J, THRINADH E, PRABHAKARAN S, KALAINATHAN S, ARIVAZHAGAN N, MANIKANDAN M (Vellore Institute of Technology (VIT), Vellore - 632 014, Email: mano.manikandan@gmail.com) : Surface modification technique to enhance metallurgical and mechanical properties of alloy C-276 weldment by laser shock peening without coating. Sadhana 2018, 43(12), 193.

Microsegregation of alloying elements is prone to hot cracking in the weldment of alloy C-276. The formation of topologically close packed phases P and $\mathrm{\mu }$ is largely responsible for the hot cracking. The present study articulates the effect of laser shock peening (LSP) to improve the metallurgical and mechanical properties of the weld joint. The weld joint was fabricated by pulsed current gas tungsten arc welding (PCGTAW) using an ERNiCrMo-3 filler wire. LSP without coating was carried out on the cap surface of the weldment. Microstructural studies were carried out to compare the as-welded and laser-peened microstructure on the fusion zone. The results show that a fine equiaxed dendritic structure was observed in both conditions. EDS analysis was carried out to evaluate the microsegregation of alloying elements. EDS analysis indicates that there are no secondary intermetallic phases. X-ray diffraction analysis was carried out to evaluate the phase change and crystallite size in the as-welded and laser shock peened fusion zone. The result shows 48.99 % reduction in crystallite size after LSP. Hardness and tensile strength results indicate there is a consequential increase in laser shock peened specimen compared with as-welded specimen.

7 illus, 4 tables, 22 ref

031079   SINDUJA A, SURULIANDI A (Computer Science and Engineering Dep, M S Univ, Abishekapatti - 627 012, Email: bloomingsindhuja@gmail.com) : Block-based tri-channel hybrid segmentation of images for foreground extraction. Sadhana 2018, 43(11), 189.

Image segmentation is crucial in image analysis, object representation, visualization and other image processing tasks. An image can be distinguished in terms of the foreground and the background. A new hybrid segmentation of images for foreground extraction is proposed, based on Interval Neutrosophic Set (INS) and Sparse Field Active Contour. In this method, an image is represented in three channels using a Gaussian filter bank and each channel is split into blocks to which the INS is applied. The resultant neutrosophic image for three channels undergoes isodata thresholding to obtain the tri-channel edge image, which is segmented using the Sparse Field Active Contour. The proposed method is evaluated by conducting three different experiments in natural image datasets like the Semantic Dataset100, Weizmann_Seg_DB_1obj, BSR and standard MATLAB test images. Finally, it is compared to other existing segmentation methods, which shows promising achievement in terms of their evaluation metrics like overlap-based metrics, pair-counting-based method and distance measures.

8 illus, 5 tables, 43 ref

031053   CHAUBEY A, BHATTACHARYA B, MANDAL S K D (Indian Institute of Technology, Kharagpur - 721 302, Email: aabha.vns1986@gmail.com) : Attributes of good teaching in engineering education in Indian subcontinent. Sadhana 2018, 43(11), 188.

Engineering education in India has been facing considerable challenges in regard to good teaching and knowledge deployment. Therefore demands new teaching methods and learning approaches thus must be developed in the field. The present review explores the concept of good teaching practices affecting performance of students in higher education with special reference to engineering education in India. With the advent of new technologies and tools, it is also vital to study the effectiveness of teaching methodologies; therefore, the review is intended to demarcate the factors which can be used to evaluate the good teaching among students. This study also explains the research done on engineering education in India in the past and recognizes the major factors influencing the same.

4 illus, 111 ref

031070   PATIL N G, HOTTA T K (Vellore Institute of Technology (VIT), Vellore - 632 014, Email: naveenpatil.g@vit.ac.in) : Role of working fluids on the cooling of discrete heated modules: a numerical approach. Sadhana 2018, 43(11), 187.

The study has focused on the role of working fluids (air, water and FC-72) on the cooling of discrete heated modules under free, forced and mixed convection medium. Three non-identical protruding discrete heat sources are arranged at different positions on a substrate board following golden mean ratio (GMR). Numerical simulations for these heat sources are carried out using a commercial software (ANSYS-Icepak R-15) to simulate their flow and temperature fields under three different modes of heat transfer. Results suggest that the temperature of the heat sources is a strong function of their size, position on the substrate board, the velocity of the fluid and type of working fluid used. A correlation has been proposed for the temperature of these heat sources keeping in mind their strong dependence on the afore-mentioned parameters. It has been found that water can be used for better heat removal from the heat sources due to its high boiling point. The whole idea gives a clear insight to the electronic cooling engineers regarding the selection of working fluids and modes of heat transfer for the cooling of electronic components.

11 illus, 4 tables, 19 ref

031069   PATEL V M, MEHTA H B (Mechanical Engineering Dep, Sardar Vallabhbhai National Institute of Technology, Surat - 395 007, Email: patelvipulm1992@gmail.com) : Thermal performance prediction models for a pulsating heat pipe using Artificial Neural Network (ANN) and Regression/Correlation Analysis (RCA). Sadhana 2018, 43(11), 184.

Pulsating heat pipe (PHP) is one of the prominent research areas in the family of heat pipes. Heat transfer and fluid flow mechanism associated with PHP are quite involved. The analytical models are simple in nature and limited in scope and applicability. The regression models and Artificial Neural Network (ANN) are also limited to a number of input parameters, their ranges and accuracy. The present paper discusses the thermal performance prediction models of a PHP based on ANN and RCA approach. Totally 1652 experimental data are collected from the literature (2003–2017). Nine major influencing input variables are considered for the first time to develop the prediction models. Feed-forward back-propagation neural network is developed and verified. Backward regression analysis is used in RCA-based regression model. Linear and power-law regression correlations are developed for input heat flux in terms of dimensionless Kutateladze (Ku) number, which is a function of Jakob number (Ja), Morton number (Mo), Bond number (Bo), Prandtl number (Pr) and geometry of a PHP. The prediction accuracy of present regression models (R² = 0.95) is observed to be better as compared with literature-based correlations.

10 illus, 10 tables, 63 ref