Browsing by Issue Date, starting with "1985"

Now showing 1 - 20 of 344

Polarographic assay of nitrazepam formulations
(1985) Arvind K. Mishra; Kamalakar D. Gode
A simple, rapid, d.c. polarographic method has been developed for the determination of nitrazepam in its pharmaceutical formulations. Ethanol was employed as the solvent for extracting the drug from the formulations and five different buffer systems, namely hydrochloride (pH 1.0-2.2), Mcllvaine (pH 2.2-8.0), acetate (pH 3.6-5.6), borate (pH 7.8-10.0) and Britton - Robinson (pH 2.0-12.0), were used individually as the supporting electrolyte. Nitrazepam is reduced in two-step, irreversible, diffusion-controlled and pH-dependent waves. Results obtained by the proposed method are in excellent agreement with those given in the British Pharmacopoeia. Commonly used tablet excipients were found not to interfere. A comparison was also made with different batches of nitrazepam tablets and capsules by the proposed method. Nitrazepam determination; d.c. polarography; pharmaceutical formulations.
Influence of Conspecific Males on the Oestrous Cycle of Underfed Female Mice
(1985) B.K. Gangrade; C.J. Dominic
[No abstract available]
On Shrinkage Estimation of the Exponential Scale Parameter
(1985) B.N. Pandey; Rakesh Srivastava
This paper shows some simple shrunken estimators for the scale parameter of an exponential distribution and compares them with minimum MSE estimator and the estimator proposed by Pandey. We have also obtained a Bayes estimator, which is a shrinkage estimator and Hasan smaller MSE than the estimator (sample mean) n/(n + 1) ifsample {###} size, n, is small and other restrictions apply. © 1985 IEEE
Effects of caffeine on the sporulation and spore germination in the green alga stigeoclonium pascheri
(Springer Netherlands, 1985) S.C. Agrawal
The treatment of vegetative cells of Stigeoclonium pascheri with caffeine delayed the initiation of sporulation and decreased the percentage sporulation. However, the treatment of spores with 500 and 1000 ppm caffeine for short durations accelerated the initiation of spore germination and increased the percentage spore germination. © 1985 Institute of Microbiology, Academy of Sciences of the Czech Republic.
Sero-conversion response to Mevilin-L measles vaccine at age 6-15 months
(1985) G.P. Katiyar; G. Kaur; D.K. Agarwal; A.K. Gulati; A. Kalra
[No abstract available]
Investigations on the structural and hydrogenation characteristics of LaNi5, HoNi5, GdNi5, SmNi5, MmNi5, and CFMmNi4.5Al0.5 thin films
(1985) S.K. Singh; A.K. Singh; K. Ramakrishna; O.N. Srivastava
This communication deals with the investigations made on synthesis, structural characteristics, hydrogen absorption behaviour and electrical resistivity variation with hydrogenation in thin films of rare earth metal pentanickelides-RNi5 where R = La, Sm, Gd, Ho and Mm (Mischmetal) and a related phase cerium-free MmNi4.5Al0.5. The synthesis of the above mentioned intermetallics was accomplished by suitable solid-state interdiffusion and homogenization. The as-synthesized flux were characterized by X-ray diffraction. The thin films prepared by vacuum thermal vapour deposition were characterized by transmission electron microscopy in various modes. These films were amorphous and transformed to crystalline form on annealing. The hydrogen absorption behaviour (both in bulk and thin films) was studied by employing electrolytic method. It was found that amorphous forms absorb more hydrogen than their crystalline counterparts. The variation of electrical resistivity with hydrogen absorption in thin-film form of various intermetallics was also studied. Plausible explanations for the above hydrogenation characteristics have been outlined. © 1985.
Structural characterization of dimethyltin(IV) bis (O‐ethyldithiocarbonate)
(1985) V.K. Gupta
[No abstract available]
HIGH-STRENGTH ALUMINIUM ALLOYS THROUGH RAPID SOLIDIFICATION PROCESSING.
(Trans Tech Publ, 1985) C. Suryanarayana; P. Ramachandrarao; T.R. Anantharaman
The techniques of rapid solidification are over two decades old and their beneficial effects, viz. , refinement of grain size, extension of solid solubility limits and formation of metastable intermediate phases as well as metallic glasses are now well established. After reviewing the various principles and techniques available to quench or rapidly solidify metallic melts at very high cooling rates, methods of consolidating the rapidly-solidified particulates are described. The types of microstructures developed and their control are discussed. A critical review of the literature reveals that the above-mentioned metastable effects of rapid solidification either singly or jointly lead to improved properties of the materials. New alloys can now be designed from first principles to achieve high specific strength and high specific modulus of elasticity. The development work done in aluminium alloys is reviewed with special reference to the Varanasi investigations.
Isolation of a hydroxyproline-secreting pigment-deficient mutant of Nostoc sp. by metronidazole selection
(Kluwer Academic Publishers, 1985) H.D. Kumar; A.K. Tripathi
A pigment-deficient mutant of Nostoc sp. was induced by N-methyl-N′-nitro-N-nitrosoguanidine and selected in a medium containing metronidazole. It formed chains of heterocysts, grew more slowly than the control, and excreted hydroxyproline into the medium, imparting a pinkish-brown colour to the cultures. © 1985 Oxford University Press.
Synthetic, Structural And Antifungal Studies Of Some 3D-Metal Complexes Of Salicylaldehyee-2-Furanthi0Carb0Xyhydraz0Ne
(1985) N.K. Singh; Miss Seema Agrawal; R.C. Aggarwal
Salicylaldehyde-2-furanthiocarboxyhydrazone (HL) fonns the adducts Ni(H2L)2Cl2and cu(h2L)C12 and deprotonated complexes having a 1:1, 1:2 and/or 1:3 metal-to-ligand ratio. Magnetic and electronic spectral studies suggest octahedral geometry for V0L.2H20fCr(HL)3, Ni(H2L)2Cl2, co(hl)3, co(hl)(L) and cu(hl)2 and square planar geometry for all other Ni(II) and Cu(ll) complexes. ESR spectral studies indicate a dxyground state for V0L.2H20 and d2_ 2 for Cu(ll) complexes. Further the ESR data also suggest one and two nitrogen(s) are coordinated to the metal ion. 1 H NMR studies of Zn(HL)2suggest the deprotonation of the phenolic proton and the presence of a coordinated ethanol molecule in ZnL.EtOH. Infrared spectral studies show that H21, behaves as a neutral bidentate in the adducts, as a uninegative bidentate in 1:2 and 1:3 deprotonated complexes and as a binegative tridentate in 1:1 deprotonated complexes. The ligand and its 1:2 deprotonated complexes of Mn(Il), Co(IH) and Cu(II) have been tested for their fungicidal action against Aspergillus niger and Rhizopus oryzae in which the Cu(ll) complex displayed the maximum fungi toxicity. © 1985, Taylor & Francis Group, LLC. All rights reserved.
Oxytocic action of prostaglandin E1 - Role of 5-hydroxytryptamine
(1985) S.B. Acharya; S.K. Bandopadhaya; A.K. Sanyal
[No abstract available]
Far-infrared absorption in liquid methane a theoretical study
(1985) C.G. Joslin; S. Singh; C.G. Gray
We present a simple theory of the far-infrared collision-induced absorption spectrum of liquid methane. We assume that CIA arises through octopolar and hexadecapolar induction. By neglecting the small anisotropy in the intermolecular potential, we can represent the spectral profile as convolutions of single-molecule free rotation spectra with intermolecular trans-lational components. Information theory is used to estimate the ' least biased ' form for the latter, based on our knowledge of their zeroth and second spectral moments (the calculation of these moments is described in an appendix). In this way we avoid the need to make questionable assumptions about the system dynamics. Our theory contains no adjustable parameters, yet the computed lineshapes are in excellent agreement with the available experimental data. © 1985 Taylor & Francis Group, LLC.
Solubility equilibria of solid solutions of hydroxyl- and chlor-apatite of arsenic
(1985) T.S.B. Narasaraju; P. Lahiri; P.R. Yadav; U.S. Rai
The solubility equilibria of arsenic hydroxylapatite, Ca10(AsO4)6(OH)2, chlorapatite, Ca10(AsO4)6(Cl)2, and their nine solid solutions were investigated at 37°C in the pH range, 4.6 to 7.8, in buffered systems through microanalytical determination of calcium, arsenic and chloride in their saturated solution. Stoichiometric dissolution of the samples was proved by the constancy of the ionic products of the apatite phase in the saturated solution. © 1985.
Hydrodynamic Lubrication of Rigid Nonconformal Contacts in Combined Rolling and Normal Motion
(1985) M.K. Ghosh; J. Hamrock; D. Brewe
A numerical solution to the problem of hydrodynamic lubrication of rigid point contacts with an isoviscous, incompressible lubricant has been obtained. The hydrodynamic load-carrying capacity under unsteady (or dynamic) conditions arising from the combined effects of squeeze motion superposed upon the entraining motion has been determined for both normal approach and separation. Superposed normal motion considerably increases net load-carrying capacity during normal approach and substantially reduces net load-carrying capacity during separation. Geometry has also been found to have a significant influence on the dynamic load-carrying capacity. The ratio of dynamic to steady state load-carrying capacity increases with increasing geometry parameter for normal approach and decreases during separation. The cavitation (film rupture) boundary is also influenced significantly by the normal motion, moving downstream during approach and upstream during separation. For sufficiently high normal separation velocity the rupture boundary may even move upstream of the minimum-film-thickness position. Sixty-three cases were used to derive a functional relationship for the ratio of the dynamic to steady state load-carrying capacity β in terms of the dimensionless normal velocity parameter q (incorporating normal velocity, entraining velocity, and film thickness) and the geometry parameter α. The result is expressed in the form The ratio of the dynamic to steady state peak pressures in the contact ξ, increases considerably with increasing normal velocity parameter during normal approach, with a similar decrease during separation. The ratio is expressed as a function of q and α by. © 1985 by ASME.
Cytomorphological Studies of Dodecaploid (12x) Solanum nigrum Linn
(1985) R.N. Singh; S.K. Roy
Dodecaploid (12x) Solanum nigrum attained the highest level of ploidy in this genus with the help of colchicine. Cytomorphological studies have shown the colchiploid to have reduced height but larger, leathery leaves with broader stomata. The berries were bigger with larger and more numerous seeds in them. Pollen were bigger yet mostly fertile (85%). The induced dodecaploid (12x) plant showed diploid like meiosis which was unexpected at such a high level of autoploidy. © 1985, Japan Mendel Society, International Society of Cytology. All rights reserved.
Cadmium uptake in anacystis nidulans: Effect of modifying factors
(1985) S.P. Singh; Vibha Yadava
Cd2+ uptake rates in the cyanobacterium Anacystis nidulans IU 625 (ATCC 27144) were found to be concentration-dependent. While Ca2+ and Zn2+ showed competitive inhibition, Hg2+ enhanced Cd2+ uptake. The pH values optimal for growth of the organism (pH 8.5) resulted in more Cd2+ uptake than low (pH 6.5) or high pH (10.0) conditions. Dithiol (dithiothreitol) proved more effective in lessening Cd2+ uptake than monothiol (mercaptoethanol). The test organism suspended in spent medium showed negligible Cd2+ uptake. Among the sythetic complexans, EDTA inhibited metal uptake, while citrate favored the process. There was more Cd2+ uptake by dense cultures, but the specific rate expressed per unit protein was less. © 1985, Applied Microbiology, Molecular and Cellular Biosciences Research Foundation. All rights reserved.
Polarised raman and infrared spectra and vibrational analysis for α-naphthylamine
(Springer India, 1985) R. Shanker; R.A. Yadav; I.S. Singh; O.N. Singh
The Raman spectrum of polycrystalline α-naphthylamine was recorded in the region 100-4000 cm-1. Polarisation measurements were made in CS2 and CHCl3 solutions. The infrared spectrum was recorded in nujol mull in the region 200-4000 cm-1. The resolution was better than 2 cm-1 and the accuracy of the measurements was within ± 2 cm-1 for all the spectra. Vibrational assignments have been proposed for the observed frequencies. Out of the 54 normal modes of vibrations, 51 modes could be observed experimentally. © 1985 Indian Academy of Sciences.
Antagonistic effect of progesterone towards estradiol dipropionate-induced changes in glycogen content in uterus and vagina of P-mice
(Birkhäuser-Verlag, 1985) G. Tripathi; A. Krishna
Estradiol dipropionate induces an increase (3-fold) in the uterine glycogen content and a decrease (4-fold) in the vaginal glycogen content of Parkes (P) mice. Progesterone antagonizes this estradiol dipropionate-induced response in both the uterine and vaginal tissue. The degree of this antagonism is more pronounced in the uterus than in the vagina. © 1985 Birkhäuser Verlag.
Circuit for quick monitoring of solar cell parameters
(1985) S.L. Singh; A.K. Saxena; R. Swami; R.P. Singh; S. Chandra
A circuit is described which automatically senses the maximum attainable power from a solar cell and displays it on a readout meter. The same meter can be used for measuring Voc and Isc.
Polarographic Studies on Aqueous Solutions of Poly-o-xylylviologen Dibromide
(1985) B.B. Prasad
Dropping mercury electrode polarography of the redox polymer poly-o-xylylviologen dibromide in water gave two well-defined irreversible diffusion controlled reduction waves over the pH range 1.70 to 6.40. The half-wave potentials for both waves (Wave I) = -0.404 V, E 1 /2 (Wave II)= -0.981 V vs SCE) are independent of pH and the total concentration of the solutions. However, the gross effect of pH on the relative wave heights suggests that an equilibrium of the type BH =+ H' + B (where B represents the compound studied) exists in solution where the reduction of the protonated as well as of unprotonated form of the polymer results in Waves I and 11, respectively. A tentative mechanism for the reduction processes is proposed. The dissociation constant of the protonated species was found to be 1.0 X 0.1 M) on calculation from a pH-dependence study of the limiting currents for both waves at a particular concentration. © 1985, Taylor & Francis Group, LLC. All rights reserved.