1. Faculty Publications
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Item Asbestos mining - campaign against its utilisation in western world(1989) Venkat Reddy D.[No abstract available]Item �ber den Einflu� von Schwefelwasserstoff auf die Korrosion des Eisens in sauren L�sungen(1979) Ramchandran, T.; Bohnenkamp, K.An Eisenelektroden wurden in anges�uerten Perchlorat und Sulfatl�sungen nach Einleiten von Schwefelwasserstoff erheblich ver�nderte Stromdichte?Potentialkurven beobachtet. Gegen�ber den reinen L�sungen ergeben sich mit Schwefelwasserstoff stark erh�hte anodische Stromdichten und bis um den Faktor 10 erh�hte Korrosionsgeschwindigkeiten. Dabei sind die anodischen Tafelgeraden log iA = f (E) mit H2S nur rund halb so steil wie ohne H2S. Wahrscheinlich wirken die SH??Ionen �hnlich wie die OH??Ionen als Katalysator der Eisenaufl�sung, sind aber bis fast zur S�ttigung absorbiert. Copyright � 1979 Verlag GmbH & Co. KGaA, WeinheimItem Transportation of granite statues(1989) Basavarajaiah, B.S.This paper deals with the problems faced during the transportation of two large granite monolith statues weighing 180 t and 120 t respectively through the narrow and winding country-roads on the western plains of the state of Karnataka. A brief resume of the problems faced during this operation and how these were overcome successfully have been presented.Item Wood burning cook stoves(1989) Nijaguna, B.T.; Uppin, S.B.The major domestic energy needs of people in the under-developed and developing countries are met by burning wood in cook stoves. The quest for energy conservation and its efficient use has motivated researchers the world over to look for improvements in wood burning cook stoves. Even a marginal increase in efficiency can contribute considerably to a total saving in energy consumption and therefore conservation. Analysis of cooking using wood shows that better energy efficiency can be achieved by complete and controlled combustion of wood, maximum energy transfer to food cooked and reducing the energy losses. The various component design features that contribute to better utilisation of wood energy are discussed. These can be of use in emerging designs, or in the modifications to the existing designs. In addition to dealing with the sizing factors, the rating or performance testing of wood stoves is detailed, thus providing a basis for comparison of different stoves. Operational guidelines that contribute to increased efficiency during cooking are provided.Item WAVE FORCE COEFFICIENTS ON SUBMARINE PIPELINES - AN OVERVIEW.(1984) Pranesh, M.R.; Somanatha, G.S.The use of submarine pipelines for economical and safe transportation of hydrocarbons is inevitable. As the applicability of pipelines are extended to other purposes, pipeline mileage is increasing alarmingly and into more hostile environment. Since wave force on submarine pipelines is identified to be a major force estimation of wave forces is of vital importance for design purposes. In this paper, an attempt has been made to identify possible reasons for discrepancies in the results of hydrodynamic coefficients. Various experimental results of wave forces on pipelines in newly constructed 2 m wide wave flume are also compared with the results available in literature. Based on the analysis, hydrodynamic coefficients to be used in the design are suggested.Item Vapor phase oxidation of p?xylene(1978) Mathur, B.C.; Viswanath, D.S.The kinetics of the vapor phase oxidation of p?xylene over ferric molybdate catalyst were studied in an isothermal, differential, tubular flow reactor in the temperature range of 360 to 420� C. The major product obtained was p?tolualdehyde with small amounts of maleic anhydride and p?toluic acid. No terephthalic acid or CO2 were observed. The reaction rate data collected fit the redox model given by Equation 1. The values of activation energies Ex, Eo and frequency factors Ax, Ao obtained are 72, 63 kJ/mol and 0.64, 2.89 m3/kg catalyst s respectively. The reaction mechanism was established by studying the oxidation of p?tolualdehyde, toluic and terephthalic acids. It is concluded that the reaction follows a parallel?consecutive scheme. Copyright � 1978 Canadian Society for Chemical EngineeringItem Texture dependent stress corrosion failure of commercial titanium sheets in bromine-methanol solution(1980) Sudhaker, Nayak, H.V.; Vasu, K.I.; Prasad, Y.V.R.K.The stress corrosion cracking (SCC) characteristics of ?-titanium sheets in a bromine-methanol solution have been studied in the annealed and cold-rolled conditions using longitudinal and transverse specimens. The times to failure for annealed longitudinal specimens were longer than those for similarly tested transverse specimens. The cold-rolled specimens developed resistance to SCC, but failed by cleavage when notched, unlike the intergranular separation in annealed titanium. The apparent activation energy was found to be texture dependent and was in the range 30 to 51 kJ mol-1 for annealed titanium, and 15kJ mol-1 for cold-rolled titanium. The dependence of SCC behaviour on the texture is related to the changes in the crack initiation times. These are caused by changes in the passivation and repassivation characteristics of the particular thickness plane. The thickness planes are identified with the help of X-ray pole figures obtained on annealed and cold-rolled material. On the basis of the activation energy and the electrochemical measurements, the mechanism of SCC in annealed titanium is identified to be the one involving stress-aided anodic dissolution. On the other hand, the results on the cold-rolled titanium are in support of the hydrogen embrittlement mechanism consisting of hydride precipitation. The cleavage planes identified from the texture data match with the reported habit planes for hydride formation. 1980 Chapman and Hall Ltd.Item Test performance of a ten tonnes reinforced concrete loading frame(1974) Raju, H.K.; Basavarajaiah, B.S.The paper reports an experimental investigation on a reinforced concrete loading frame of ten tonnes working load capacity. The loading frame was fabricated by using two doubly reinforced concrete beams to serve as flexural members. Eight numbers of mild steel rods connected to the beams by plates and nuts served as supports for the beams and also as tension members during testing of structural elements. The stress distribution and loadeflexion characteristics of the flexural members of the frame was investigated in the working load range of to tonnes. Theoretical and experimental observations indicated that the flexural member behaves like a beam with partial fixity at the ends. 1974 Secr tariat de R daction.Item Studies on spinodal decomposition in Cu-27Ni-2Cr alloy(1986) Rao, P.P.; Agrawal, B.K.; Rao, A.M.Transformation characteristics of a Cu-27Ni-2Cr alloy were studied on ageing in the temperature range of 773 to 1073 K, by means of X-ray diffraction and transmission electron microscopy. It was concluded from morphological features that the alloy undergoes spinodal decomposition and the coherent spinodal was estimated to be 946 K. Yield stress increment on ageing was found to follow monotonically the strain amplitude and to be independent of the wavelength of composition modulation. 1986 Chapman and Hall Ltd.Item Stress corrosion failure of Zircaloy?2 sheets in methanolic HCl solution: Role of crystallographic texture(1982) Hebbar, K.R.; Sudhaker, Nayak, H.V.; Ramchandran, T.The stress corrosion cracking (SCC) characteristics of Zircaloy?2 sheets in methanol?0.4 vol. pct. hydrochloric acid have been studied in the annealed and cold?rolled conditions using longitudinal and transverse specimens. The times to failure for annealed longitudinal specimens were longer than those for similarly tested transverse specimens at stress levels below ?45% UTS. The cold?rolled specimens developed resistance to SCC, but failed totally by cleavage when notched, unlike annealed specimens which failed by intergranular initiation followed by cleavage. The crystallographic texture developed by cold rolling is such that the crack initiation is difficult because of quicker passivation characteristics of the crack initiating plane. The texture also gives unfavourable orientation of slip and twinning planes with respect to tensile axis. The crack initiating planes are identified with the help of X?ray pole figures. The apparent activation energy is found to be texture dependent at a given stress level. On the basis of apparent activation energy measurements, dynamic tests at constant cross?head speeds and electrochemical measurements, the mechanism of SCC is identified to be the one involving stress?aided anodic dissolution. Copyright 1982 Verlag GmbH & Co. KGaA, Weinheim