Showing papers by "Indian Institute of Technology Bombay published in 1968"
TL;DR: In this article, the same species is absorbed in all the cases studied and that it has the composition HCO, and it is probable that COOH radicals are also present to a certain extent.
45 citations
TL;DR: In this paper, a general method of solution is presented with the help of which one can satisfy exactly arbitrary boundary conditions prescribed on the curved and flat surfaces of a hollow or solid cylinder of any length.
35 citations
TL;DR: In this article, the theoretical maximum ideal pumping efficiency of a water jet pump is 50% at a flow ratio of unity, and a pump designed with theoretically obtained optimum dimensions, a maximum efficiency of 39.8% was achieved.
Abstract: The theoretical maximum ideal pumping efficiency of a water jet pump is 50% at a flow ratio of unity. Pump performance can be predicted theoretically. With a pump designed with theoretically obtained optimum dimensions, a maximum efficiency of 39.8% was achieved. Efficiencies on the order of 42% could be obtained by selecting proper materials to reduce friction losses to a minimum. If a jet pump with fixed nozzle is constructed for maximum efficiency, the area ratio should be between 0.33 to 0.543; for adjustable nozzle pumps, the area ratio should be about 0.205, and the pump should be operated at a nozzle distance of one to two nozzle diameters.
30 citations
TL;DR: In this article, the kinetics of anodic oxidation of the organic species adsorbed on platinized platinum from methanol, formic acid and CO2 solutions have been investigated.
17 citations
TL;DR: With the help of the Kubo formula an expression for the electrical conductivity of metals is obtained within the Hartree-Fock approximation using the method of double time temperature dependent Green's function.
Abstract: With the help of Kubo formula an expression for the electrical conductivity of metals is obtained within the Hartree-Fock approximation using the method of double time temperature dependent Green's function. A simple calculation of the relevant relaxation time appearing in the expression is presented. This gives a reasonably good estimate of the electrical conductivity of metals.
Mittels der Formel von Kubo wird ein Ausdruck fur die elektrische Leitfahigkeit der Metalle gewonnen, wobei in der Hartree-Fock-Naherung die Methode der doppelt zeit-temperaturabhangigen Greenschen Funktion benutzt wird. Eine einfache Berechnung wird fur die in dem Ausdruck erscheinende Relaxationszeit angegeben. Damit ergibt sich eine ziemlich gute Abschatzung der elektrischen Leitfahigkeit von Metallen.
10 citations
TL;DR: In this paper, the authors proposed an experimental procedure to evaluate the coefficients of these polynomials to find the best approximation to the impulse response of a linear time invariant system.
Abstract: Impulse response of linear time invariant systems is partitioned by dividing time axis into equal intervals of time. Then impulse response is expressed as a sum of partitioned portions of impulse response. Each individual portion of impulse response is approximated by a finite sum of Legendre polynomials, satisfying integral squared error criterion. In this investigation an experimental procedure is suggested to evaluate the coefficients of these polynomials to cahieve the best approximation. Knowing these coefficients the best approximation to impulse response is obtained us illustrated by the examples considered. If the coefficients of the input signal are also known then it is shown that the values of the output response at the partitioning instants can be computed.
8 citations
6 citations
TL;DR: In this paper, an analysis of the propagation phase constant β of a T.E.M. wave in plasma is made introducing a new factor wo that is proportional to the elastic restoring force on an electron in the space charge region under the influence of the electric field.
Abstract: An analysis of the propagation phase constant β of a T.E.M. wave in plasma is made introducing a new factor wo that is proportional to the elastic restoring force on an electron in the space charge region under the influence of the electric field. From the experimental determination of β pin the anomalous dispersion region, the electron density Nc and the collision frequency v are obtained.
6 citations
TL;DR: In this investigation the impulse response h(t) is approximated by a set of ortho-normalized damped exponentials satisfying the integral squared error criterion, which leads to the synthesis of a system model approximating the system.
Abstract: It is a well-known fact that the impulse response completely identifies a linear system. In this investigation the impulse response h(t) is approximated by a set of ortho-normalized damped exponentials satisfying the integral squared error criterion. An analogue computer instrumentation is suggested to evaluate the generalized Fourier coefficients of impulse response. To evaluate these coefficients the time reversal of the orthonormal set is essential. This is achieved on an analogue computer by inserting inverters in series with all integrators. The method Suggested in this investigation directly leads to the synthesis of a system model approximating the system.
5 citations
TL;DR: By applying field theory and transmission line theory, the Q-factor of a surface-wave resonator is derived in this article, where the effect of tilt and rotation of one of the end-plates on the Qfactor is also studied.
Abstract: By applying field theory and transmission line theory, the Q-factor of a surface-wave resonator is derived. A new technique for determining the Q-factor is developed. Attenuation constants of Sommerfeld and Goubau surface-wave lines of different diameters are determined from a large number of measurements of Q-factor as a function of length of the resonator. The effect of tilt and rotation of one of the end-plates on the Q-factor is also studied. Radiation loss is evaluated. The paper also contains power-flow calculations and experimental verifications of the radial field spread for Sommerfeld and Goubau lines. Physical realizability of the Sommerfeld wave is confirmed.
4 citations
TL;DR: In this paper, an analogue computer sot-up which acts as a delayor is suggested for evaluation of the coefficients of the input and output of a linear differential equation of the system.
Abstract: The dynamic performance of many physical systems is adequately described by an ordinary linear differential equation of the form: where x(t) is the forcing function or the input to the system and y(t) is the response on the output of the system. If the coefficients a i , referred to as the parameters of the system, are known then the system is said to be completely known. In this investigation a method is suggested to evaluate these coefficients by performing measurements on the input and output of the system. The method suggested hero is the inverse of what is known as the method of undetermined coefficients. If the input is a polynomial in t then the steady state response of the system is also a polynomial in t. Knowing the coefficients of the input and output the system parameters a i can be evaluated. An analogue computer sot-up which acts as a delayor is suggested for evaluation of the coefficients of the input and output. The general scheme is given which can be used for continuous tracking of the s...
TL;DR: In this article, the authors considered the stress problem of a thin cylindrical shell supported by an elastic core of a different material and subjected to arbitrary loading on its curved surface, and solved the problem by applying the three-dimensional theory of elasticity to the core and using membrane or bending solutions for the shell.
Abstract: The stress problem of a thin cylindrical shell supported by an elastic core of a different material and subjected to arbitrary loading on its curved surface is considered. The problem is solved by applying the three-dimensional theory of elasticity to the core and using membrane or bending solutions for the shell. Equilibrium and compatibility equations are satisfied at the junction of the shell and the core. It is pointed out that the procedure can easily be extended to the case of a hollow core with or without another shell of another material in it. Numerical results are presented to illustrate the effectiveness of even a weak core in reducing the shell stresses.
TL;DR: In this paper, it was proved that the sum of the sampled values of the output response, at the sampling interval equal to the period of the input wave, directly yields the sign and cosine transforms respectively.
Abstract: Evaluation of the Fourior transform of the system impulse response is an important aspect of the design of control systems. A method suggested hero requires only one cycle of sine or cosine wave to be applied as an input to the system. It is proved that the sum of the sampled values of the output response, at the sampling interval equal to the period of the input wave, directly yields the sign and cosine transforms respectively. The procedure is generalized to any number of complete cycles of input wave, as well as to n/2 cycles whore n is any odd positive integer.
TL;DR: In this article, a theoretical equation for estimating the mixing loss coefficient is given for mixing of two concentric jets with water as the working fluid, which has been experimentally verified with two outer nozzles of semicone angles of 12 and 24.
Abstract: A theoretical equation for estimating the mixing loss coefficient is given for mixing of two concentric jets. The equation has been experimentally verified with water as the working fluid. In the experiments, two outer nozzles of semicone angles of 12○ and 24○ were used for different velocity ratios varying from 0.00824 to 0.792. For an area ratio of 0.228 and main nozzle semicone angle of 12○ four nozzle distances of 2.4 cm, 3.4 cm, 4.4 cm, and 7.9 cm were tested. The mixing loss constant reduces with increase in velocity ratio to unity, beyond which it increases with increase in velocity ratio for a given area ratio and angle. The mixing loss constant increases with nozzle angle when all other parameters are constant. For a particular mixing configuration the mixing efficiency increases with nozzle distance and reaches an optimum value; with further increase of nozzle distance it decreases. An optimum efficiency for mixing of the order of 98% was obtained at a velocity ratio of 0.642 for a nozzle semicone angle of 24○ at a nozzle distance of 7.9 cm.
TL;DR: In this paper, the frequency of damped oscillations f0 in the presence of a r.c.f. field in a plasma model in equilibrium was analyzed and a complete analysis of this subject was made.
Abstract: In a previous paper (Bhagavat and Nandedkar 1968) an analysis of the frequency of damped oscillations f0 in the presence of a r.f. field in a plasma model in equilibrium was made. This paper makes a complete analysis of this subject in the presence of a d.c. field. An experimental investigation of the variation of f0 with the electron density and a d.c. field is described.
TL;DR: In this paper, 2-Thenoyltrifluoroacetone is used for the extractive spectrophotometric determination of ruthenium at ph 4.0 (acetate buffer).
Abstract: 2-Thenoyltrifluoroacetone is used for the extractive spectrophotometric determination of ruthenium at ph 4.0 (acetate buffer). Beer's law is obeyed over the range 6–42μg/ml at 450 nm. The colour is stable for 72 hours. The metal can be extractively separated from several noble and other metals.
01 Aug 1968
TL;DR: In this article, a selective elution method was used to separate copper from brass and gun metal using Dowex 50 W X-16 resins and ammonium acyclic acid.
Abstract: Copper is separated from zinc, nickel and lead on the cation-exchange resin Dowex 50 W X-16 by selective elution. 0.5 M ammonium acetate solution is used for the elution of copper, 1.0 M ammonium chloride solution for zinc, 1.2 M hydrochloric acid for nickel and 0.25 M ammonium acetate solution for lead. The method is applied to the separation of copper from brass and gun metal. The errors are about ± 2.5%.
TL;DR: In this article, the conditions for maximum values of amplitude and velocity of displacement are derived for an electron in a plasma and conditions for resonance as well as the position of half-energy density points are given.
Abstract: The oscillatory motion of an electron in a plasma is analysed and the conditions for maximum values of amplitude and velocity of displacement are derived. Energy associated with equivalent inductive and capacitive circuits is discussed and the conditions for resonance as well as the position of half-energy density points are given. It is shown that the velocity of energy transport at half-energy density points is twice its value at resonance.