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 | Exterior Problem of a Finite Cylindrical Cavity in Elasto-Dynamics
Author : Viswanathan, K. ;Ram Kumar;Chandra, Jagdish
Source : Defence Science Journal ; Vol:32(3) ; 1982 ; pp 175-187
Subject : 620.261 Explosives
Keywords : Explosives ;Acoustic radiation
Abstract : The elasto-dynamic problem of a finite cylindrical cavity in an infinite elastic solid has been studied. In order to satisfy the radiation conditions at infinity, the solution has been assumed in terms of Spherical Hankel functions and in order to satisfy the conditions at the boundary of the cavity, the method of least square approximation has been used for the minimisation of the errors on the boundary. The radiation patterns of displacements are given for two sets of frequencies and aspect ratios. |
| | Designing YIG Drivers
Author : Prema, R. ;Nagarajan, A.S.
Source : Defence Science Journal ; Vol:32(3) ; 1982 ; pp 189-196
Subject : 621.38 Electronics
Keywords : Microwave devices
Abstract : Design aspects of a linear, stabilized voltage to current transducer for driving YIG tuned microwave devices are analysed. Typical circuits with OP AMP interfacial input and bipolar/VMOS current amplifier outputs are sketched. Attention is drawn to such circuit refinements as (i) augmenting differentiator for minimising sweep delay; (ii) linearizer to compensate for nonlinearity due to core saturation; and (iii) low noise, low drift and minimal voltage pushing options. |
| | Dermatophytes from Apparently Healthy Toe: webs of Service Personnel Stationed in Northeastren Region of India
Author : Zachariah, K. ;Das, T.K.;Mattada, R.R.
Source : Defence Science Journal ; Vol:32(3) ; 1982 ; pp 197-199
Subject : 551.58 Climatology;551 Geology
Keywords : Climate ;Radiation hazards
Abstract : "Apparently healthy toe-webs of 230 individuals belonging to various Army units stationed India were studied for dermatophytes. 35 were found positive. This revealed the presence of 28 Trichophyton mentagrophytes, 4 Epidermophyton floccosum, 2 Microsporum gypseum and 1 T. rubrum. " |
| | Spectrophotometric Determination of Iron III after separation by adsorption of its Pyrrolidinedithiocarbamate on Nephthalene
Author : Singh, H.B. ;Satake, Masatada
Source : Defence Science Journal ; Vol:32(3) ; 1982 ; pp 201-205
Subject : 54 Chemistry;546 Inorganic Chemistry
Keywords : Chelate ;Adsorption;Polarography
Abstract : A method for the spectrophotometric determination of trace amounts of iron(III) after adsorption of its pyrrolidindeithiocarbamate on naphthalene is presented. Iron(III) forms a water-insoluble chelate with ammonium pyrrolidinedithiocarbamate in the pH range 2.9-6.6. This chelate is quantitatively adsorbed onto mycrocrystalline naphthalene at room temperature. The effects of variablesm, such as pH, amount of reagent and napthalene, digestion and shaking time, and diverse ions, have been examined. The method has been applied to the determination of iron(III) in standard reference and environmental samples and the results compared with 1,10-phenanthroline method. |
| | Note on a Viscoelastic Convection Flow
Author : Vijaya, Y. ;Harinath, K.S.
Source : Defence Science Journal ; Vol:32(3) ; 1982 ; pp 207-212
Subject : 532.542 Fluid Dynamics
Keywords : Skin friction ;Transverse magnetic;Mathematical analysis
Abstract : A mathematical analysis of the free convection flow of an incompressible viscoelastic(Rivlin-Ericksen) fluid from an infinite flat plate under variable suction acted upon by a transverse magnetic field is presented. It is found that the effect of viscoelasticity is to appreciably alter the skin-friction. |
| | Note on Armor Steel Design: A proposition
Author : George, N.T. ;Potay, S.K.
Source : Defence Science Journal ; Vol:32(3) ; 1982 ; pp 213-214
Subject : 623.4 Armaments and Ballistics
Keywords : Ballistic testing programs ;Armour;Ballistic penetration
Abstract : A theoretical approach to the ballistic penetration and armor development has been made and a single phase material with a computer evaluated optimum hardness has been proposed to give a superior performance as an armour. |
| | Problem Concerning to a Sinusoidal Flux
Author : Murthy, M.G.K. ;Murthy, D. Rama
Source : Defence Science Journal ; Vol:32(3) ; 1982 ; pp 215-218
Subject : 536 Thermodynamics
Keywords : Thermal stresses ;Thermoelasticity
Abstract : A dynamical problem, concerning to semi-infinite medium subjected to a sinusoidal flux is studied. The consequential effect of this on the associated problem of thermal stresses is studied taking into account the inertial terms. |
| | Fe(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II) Complexes of 4 Nitrobenzylidene 2 Hydroxyl 3 5 Dinitroaniline
Author : Srivastava, R.S.
Source : Defence Science Journal ; Vol:32(3) ; 1982 ; pp 219-223
Subject : 54 Chemistry;546 Inorganic Chemistry
Keywords : Explosion properties ;Transition metal complex;Ligand
Abstract : Complexes of Fe(II), Co(II), Ni(II), Cu(II) Zn(II), Cd(II), and Hg(II) with 4-nitrobenzylidene-2-hydroxy-3,5-dinitroaniline (hereafter abbreviated as nhd) have been prepared and characterized by their microanalyses, molar conductance, magnetic susceptibility, electronic and IR spectra. The donor sites of the ligand have been derived from the results of infrared spectra. |
| | Unsteady Flow of a Viscous Fluid Through an Annulus Unsteady Flow of a Viscous Fluid Through an Annulus
Author : Verma, P.D. ;Kanwal, Shakuntala
Source : Defence Science Journal ; Vol:32(3) ; 1982 ; pp 225-229
Subject : 532.542 Fluid Dynamics
Keywords : Stresses ;Viscous;Pulses
Abstract : One boundary of an annulus is fixed, and other boundary is subjected to a series of pulses. The fluid in the annulus, therefore acquires a velocity, relative to the annulus, due to the transfer of momentum from the boundary by viscous stresses. The flow relative to the annulus is determined when a constant pressure gradient and a series of pulses act together. The velocity profiles for unsteady motion, are plotted for various times and for a fixed radii ratio. |
| | Construction of Certain Infinite Families of Graceful Graphs form a Given Graceful Graph
Author : Acharya, B.D.
Source : Defence Science Journal ; Vol:32(3) ; 1982 ; pp 231-236
Subject : 51 Mathematics
Keywords : Infinite sequence ;Constructing
Abstract : Two general methods of constructing an infinite sequence(G=G/sub1/,G/sub2/....) of graceful graphs Gi such that Gi is contained in Gi/sub+1/ as an induced subgraph, for every given gracefully numbered graph G, is described along with applications of the concept of graceful graphs. |
| | On Availability of a Series system with Imperfect Detectors
Author : Ray, Debabrata ;Kapoor, Vipin B.;Ashok Kumar
Source : Defence Science Journal ; Vol:32(3) ; 1982 ; pp 237-240
Subject : 621.3 Electrical Engineering
Keywords : Steady state ;Detector
Abstract : An n-unit series system with exponential distributions for life-times and repair-time has been considered. Each unit is equipped with a detector to detect failures. Detectors are subject to two failure modes: viz. (1) instantaneous failure i.e. it fails at the time of need when a unit fails; (ii) gradual failure i.e. it fails and gives false alarm for system failure. Steady-state availability of the system is obtained by studying the underlying system equations. Behavior of steady-state unavailability has also been studied analytically. |
| | Computerized System for Evaluating Small Arm Projectile Trajectory Parameters Involving Space Time Functions
Author : Chatterjee, S.M. ;Jauhari, M.
Source : Defence Science Journal ; Vol:32(3) ; 1982 ; pp 241-249
Subject : 623.4 Armaments and Ballistics
Keywords : Arms ;Ballistics
Abstract : Evaluation of certain parameters of the trajectory of a small arm projectile on the basis of Siacci approximation requires the values of space (S) and Time (T) functions as tabulated in the Ingalls and Hodsock ballistic tables. The development is reported of a computerized system, whereby the necessity of referring to these tables has been completely obviated. Programme flow-char has been presented and the logic behind the flow of programme has been made explicit. The programme has been executed successfully on the DCM Microsystem 1121. |
| | Effect of Oxidizer Particle Size on Burning Rate and Thermal Decomposition of Composite Solid Propellants
Author : Sunitha, M.R. ;Kishore, K.
Source : Defence Science Journal ; Vol:32(3) ; 1982 ; pp 251-257
Subject : 621.1 Engines;662.3 Propellants;66 Chemical Technology
Keywords : Burning rate ;Thermal decomposition
Abstract : Studies on Thermal decomposition of ammonium perchlorarte(AP)- polystyrene(PS) propellant and burning rate of PS/AP propellant have been carried out as a function of oxidizer particle size. Thermal decomposition of AP and AP/PS propellant as function of AP particle size shows a maximum rate around 100 micro particle size which has been explained on the basis of Mample's theory. No such maximum is observed in the case of PS/AP propellant burning rate. |
| | Neutron Radiography
Author : Rao, V.N. ;Reddy, A.R.
Source : Defence Science Journal ; Vol:32(3) ; 1982 ; pp 259-273
Subject : 621.386.64 Radiography ;621.38 Electronics
Keywords : Neutron radiography ;Isotopic neutron
Abstract : The field of neutron radiography with special reference to isotopic neutron radiography has been reviewed. Different components viz., sources, collimators, imaging systems are described. Various designs of neutron radiography facilities, their relative merits and demerits , the appropriateness of each design depending on the object to be radiographed, and economics of each technique are also dealt. The applications of neutron radiography are also briefly presented. |
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