Showing papers by "Jadavpur University published in 1973"

Utilization of carbon and nitrogen sources by Streptomyces kanamyceticus for kanamycin production.

Abstract: To select a suitable synthetic medium for kanamycin production, we tested a number of carbon and nitrogen compounds for their effect on growth of Streptomyces kanamyceticus ATCC 12853 as well on kanamycin production. Galactose was found to be the most suitable carbon source, though dextrin, soluble starch, and potato starch gave moderate yields. Sodium nitrate and glycine were adequate nitrogen sources for kanamycin production. There was, however, no direct relation between the growth of the organism and antibiotic formation. The pH of the medium might be an important factor for kanamycin formation, as media giving high kanamycin yields showed an alkaline pH without exception.

The component fatty acids of chaulmoogra oil

Abstract: The fatty acid composition of the seed oils of the species, Hydnocarpus kurzii, H. wightiana and H. odorata were determined by gas-liquid chromatographic (g.l.c.) analysis. The percentages of individual fatty acids were found to be: hydnocarpic 23.0, 33.9, -; chaulmoogric 29.6, 35.0, -; gorlic 25.1, 12.8, -; lower cyclic homologues 0.3, 4.6, -; myristic 0.6, 0.8, 0.4; palmitic 8.4, 5.6, 11.8; stearic -, 0.6, 4.7; palmitoleic 6.0, 1.3, 0.5; oleic 5.4, 3.6, 21.8; linoleic 1.6, 1.8, 29.3; linolenic -, -, 31.2; respectively.

Remark on algorithm 323 [G6]

Abstract: Submittal of an algorithm for consideration for publication in Communications of the ACM implies unrestricted use of the algorithm within a computer is permissible. General permission to republish, but not for profit, all or part of this material is granted provided that ACM's copyright notice is given and that reference is made to the publication, to its date of issue, and to the fact that reprinting privileges were granted by permission of the Association for Computing Machinery. Description This algorithm analyzes the skew representation [x]-[~] of the symmetric group ~r~ corresponding to a pair of partitions r~_s m >_u~>_ \"'\" >u~ (I) X~>_ul (l_

Lattice Dynamics of Alkali Halides

Abstract: The deformable-shell model developed by Basu and Sengupta and later substantiated by a potential form by Sarkar and Sengupta has found wide application in describing the different static properties of ionic crystals of both NaCl and CsCl structures. But so far a complete calculation of dynamical properties of ionic crystals has been reported for only one crystal. Further, from a critical comparison of the different lattice-dynamical models which effectively introduce many-body interactions between the ions, we have found that there are certain differences between them, some of which are quite fundamental in nature. Moreover, of the current phenomenological models, the deformable-shell model alone is capable of reasonably treating both the static and the dynamic properties of the crystals. Hence it is important to know the results of the calculation according to different models. In this work we present the lattice-dynamic calculation on the following five crystals, NaCl, NaBr, KI, KCl, and KBr according to the deformable-shell model. In order to obtain the parameters, the well-known macroscopic quantities have been used and no least-square-fitting procedure has been adoped. The parameters obtained from the theory have been used to calculate the phonon dispersion relation in both the symmetry and the off-symmetry directions (where experimental results are available) and the variation of the Debye temperature from the frequency spectra for these crystals. We have consistently used the polarizable negative-ion model for all of them. The results thus obtained agree well with experiment. Other theoretical-model results are also discussed in detail.

Approximate shock-free transonic solution for a symmetric profile atzero incidence.

Abstract: by that around a large angled unpitched cone and that the undersurface can be roughly predicted from such an assumption Further evidence of such flow behavior comes from the oil dot flow visualization which shows that up to 45° the surface streamlines lie along straight lines generated from the nose tip Furthermore, a measurement of the undersurface pressure distribution on the body and wings at one chord position taken in one test on a sting supported model also illustrated that, as in Ref 3, fairly constant spanwise pressure was attained In Fig 4 is plotted the standoff angle of the shock A0S, on the windward side of the model, for different angles of attack (defined by the angle of the cone body axis to the stream) obtained from both free flight and fixed model shadowgraph photographs Flow resemblance mentioned in the last paragraph was used to produce the following successfully applied prediction procedure The pressure over the whole of the undersurface of the wing-cone configuration was assumed to be constant and equal to that on an unpitched cone which would generate a conical shock wave with half-angle equal to the angle of the windward side standoff shock 6S, obtained from the experiments, (ie, equal to a + 0c + A0s, from Fig 4) The integrated pressure thus obtained gives the predicted CL vs L/D curve given in Fig 2 (called here "conical flow theory") which is seen to coincide reasonably well with the measured data This prediction provided the CL ~ a curve which was supplied to the computer program described earlier A final comparison is made in Fig 2 with experimentally determined force coefficients of other appropriate configurations The lift coefficient on the wing-cone configuration at high incidences as measured in the present series of tests and as predicted by the "conical flow theory" ties in well with the low incidence data of Reggiori on a similar configuration3 The maximum lift coefficient (CL)max, achieved by the wing-cone body with lower surface concavity (present results give (CL)max~08) exceeds those of the NASA Space Shuttle 040A configuration [Ref 5, (C L)max = 057] by 40% and a flat delta [Ref 2, (QJmax = 065] by 23% To conform to the comparisons of Fig 2, the value of (CL)max used was based on the reference area equal to the planform area of the complete Space Shuttle configuration This required that the (CL)max based on an effective wing area quoted in Ref 5 as 0675 be reduced by 18% This

Some characters of the bedded chromite deposits of Kalrangi, Cuttack district, Orissa, India

Abstract: Mineralogy, size distribution of grains, and variation in chemical composition of chromitite occurring in four successive layers in serpentinite, near Kalrangi (85°45′ E:21°0′ N), Cuttack district, Orissa, have been studied to decipher the mode of formation of the ore bodies. The parent rocks are dunite-peridotite with olivine, olivine-enstatite and minor chromite, the minerals being completely altered to serpentine or talc-serpentine near the surface. The ore bodies are of bedded nature, composed entirely of chromite, and are confined to the top of the dunite-peridotite sheet. Grain-size variation of chromite in different layers in the vertical section shows straight line character which suggests accumulation of chromite grains by the process of magmatic sedimentation. The normal distribution of size variation of the chromite grains probably means that they are the products of a single magmatic cycle. Cr2O3 and MgO in chromitite decrease and FeO and Al2O3 increase in the vertical direction, which is expected when chromite crystallize from an ultrabasic magma in an undisturbed condition. Ideas of repeated injection and convection currents are negated by the absence of rhythmic layering and cyclic repetition of ultrabasics and chromite.

Partition of Boolean Functions ror Realization with Multithreshold Threshold Logic Elements

Abstract: In this paper, the concept of "primary partition" of Boolean functions has been introduced. A systematic method of obtaining the multithreshold realization of Boolean functions based on this new concept is presented. The problem essentially reduces to a table lookup procedure; the computational labor in finding the minimum-threshold minimum fan-in solution is substantially reduced.

Unified Plastic Yield Criterion for Ductile Solids

Abstract: Introduction T basic hypothesis in the theory of plasticity is that there exists a scalar function of stresses which characterizes the yielding of materials. This scalar function, also called the yield function,/(crfj.) generates a closed surface in the stress space by a relation /(o^) = 0. When a material is subjected to increasing forces and torques, it describes a path in the stress space. When this path intersects the yield surface /(afj-) = 0, the material yields and becomes plastic. All the classical failure theories, e.g., those of Tresca, Von Mises, and Reuss, give conflicting predictions of the yield stresses of metals even for such simple cases of pure torsion or elongation. The reason for the conflicts in these theories is that these theories essentially form one-parameter yield surfaces. So fitting these criteria on tensile tests alone make these incompatible with the torsion test data, and vice versa. These theories also do not predict the failure under hydrostatic compression. Detailed references on these theories can be obtained in Ref. 1. The proposed theory, on the other hand, forms a multiparameter yield surface. Here a start is made from the basic yield point data from both tensile and torsion test experiments, as well as the hydrostatic compression test. Thus the present theory can predict yielding under hydrostatic pressure while posing no conflict between theory and, at least, the basic tension and torsion experiments. The formulation is flexible enough to satisfy a large number of the available experimental data on the yield point and subsequent flow for ductile materials, and includes both ideally plastic and strain-hardening solids. The yield surface generated is invariant with respect to rotation of coordinate axes, a necessary requirement for all such criteria.

The triglyceride composition of Corchorus olitorius seed oil.

Abstract: Corchorus olitorius seed oil and its randomised product have been subjected to pancreatic hydrolysis. Glyceride compositions have been calculated from the original fatty acid composition and those of the monoglycerides produced by hydrolysis. The percent GS3 content of the seed oil and of its interesterified product have also been determined by the combined techniques of thin layer chromatography on silver nitrate impregnated silica gel and colorimetry.

Effect of different complex nutrients on neomycin production by Streptomyces fradiae H.

Abstract: Studies of the nutritional requirements of a neomycin-producing mutantStreptomyces fradiae H developed by the authors show that tapioca starch (at a concentration of 5%) is an excellent carbon source for antibiotic production while soya flour and yeast powder are superior nitrogen sources for neomycin production. A mixture of 1% soya flour and 1% yeast powder gives maximal antibiotic titer.

Active RC all-pass networks using a summation or a differential amplifier!

Abstract: The paper presents a class of active RC networks using a summation amplifier or a differential amplifier for realizing all-pass transfer functions of arbitrary order, having simple poles restricted to the negative real axis. Examples are given to realize second-order all-pass transfer functions with RC null network and with the phase-shifting network of a Wien bridge.