Showing papers by "University of Rajasthan published in 1990"
TL;DR: The physicochemical properties of metal alkoxides have been explained on the basis of inductive and steric effects, degree of association, volatility as well as alcoholysis and hydrolysis reactions as mentioned in this paper.
Abstract: In view of the increasing applications of metal alkoxides as precursors for ceramics, the physicochemical aspects of successive steps in the S-S-G process are being intensively investigated by sophisticated techniques like NMR (1H as well as multinuclear), SAXS, SANS, XANES, EXAFS and CRAMPS. Besides lower temperatures of sintering, the main advantage of the S-S-G process is the intimacy of mixing at the molecular level, resulting in the homogeneity of the final desired product. The formation of new bonds in mixtures of alkoxides has been confirmed by the isolation of polymetallic alkoxides, in which variations in the coordination environment of the central metal atom offer attractive possibilities for differing networks in ceramics with the same composition. The physicochemical properties of alkoxides have been explained on the basis of inductive and steric effects, degree of association, volatility as well as alcoholysis and hydrolysis reactions. These have been finally correlated with structural elucidation, which is being pursued much more vigorously during the past 1–2 years.
96 citations
TL;DR: Oral administration of a 50% ethanol extract of Abrus precatorius seeds in albino rats for 30 and 60 days induced an absolute infertility in males which was reversible and suppression of sperm motility in the cauda epididymis was the most pronounced effect.
56 citations
TL;DR: A tetracoordinated state of boron has been established in all the derivatives and these ligands and their corresponding organoboron complexes have been tested in vitro against a number of pathogenic fungi and bacteria and found to possess remarkable fungicidal and bactericidal properties.
38 citations
TL;DR: In this article, the authors considered the soliton solution of the KdV equation for a warm-ion magnetized plasma with two Maxwellian electron components, and the effect of ion temperature, obliqueness and magnetization on the amplitude and width of soliton was discussed in detail.
36 citations
Journal Article•
TL;DR: Dose-dependent degenerative changes in the testicular weights, sperm count, later stages of spermatogenesis and Leydig cells are observed in testis of rats treated with steroidal fraction of seeds of A. precatorius.
Abstract: Dose-dependent degenerative changes in the testicular weights, sperm count, later stages of spermatogenesis and Leydig cells are observed in testis of rats treated with steroidal fraction of seeds of A. precatorius. These are correlated with the dose-dependent decrease in the enzyme activity of 3 alpha, 3 beta, 17 beta-hydroxysteroid dehydrogenases, glucose-6-phosphate dehydrogenase, sorbitol dehydrogenase and leucine aminopeptidase. The steroidal fraction may also exert its influence indirectly at the pituitary level by a feedback mechanism, leading to decrease in production and release of testosterone which results in significant alterations in the testis.
33 citations
TL;DR: In this paper, the reaction of [PtMeX(COD)] with 2-(diphenylphosphino)pyridine (Ph2Ppy) in 1 : 2 stoichiometry yields the dinuclear complex [ptMeCl(Ppy)]2 (II).
30 citations
TL;DR: With this method of subculture the callus has retained its morphogenic potential for four years and showed varied patterns of growth and morphogenesis following transfer to media with different levels of auxins and cytokinins.
Abstract: Compact nodulated embryogenic callus differentiated from cultured seeds of Eleusine coracana (Finger Millet) on Murashige and Skoog (1962) basal medium with 2,4-dichlorophenoxyacetic acid (1.0, 3.0 mg l). This embryogenic callus was maintained on a medium with a lower level of 2,4 — dichlorophenoxyacetic acid. At every subculture the embryogenic callus had some preexisting embryoids in it. With this method of subculture the callus has retained its morphogenic potential for four years. Following transfer to media with different levels of auxins and cytokinins, the callus showed varied patterns of growth and morphogenesis. Embryoids could be germinated in profusion to form plantlets which could be transferred to the field. Shoot buds also differentiated from the whole surface of the embryoid or from the flattened meristemoids.
28 citations
TL;DR: In this paper, the condensation behavior of various fluorine containing 3-indolylimino derivatives with mercaptoacetic acid and with chloroacetyl chloride has been studied.
26 citations
TL;DR: A dialkyl tin complex of composition Bu2SnL2 (I) (L is a monofunctional bidentate ligand) has been made by reaction of ClBu2SnOSnBu2Cl with the substituted pyrazolone, PhCO C:C(OH)N(Ph)N:C CH3, in dry benzene.
25 citations
Journal Article•
TL;DR: The Sarnu-Dandali suite of ultrabasic alkaline rocks, ijolite, foidal syenite, phonolite and carbonatite is one of the few occurrences of Carbonatite-nephelinite association reported in India.
Abstract: The alkaline suite of Sarnu-Dandali (comprising ultrabasic alkaline rocks, ijolite, foidal syenite, phonolite and carbonatite) is one of the few occurrences of carbonatite-nephelinite association reported in India. The suite is intrusive into the Lower Cretaceous sedimentaries. The rocks show a continuous gradation from alkali pyroxenite to feldspathic ijolite through micro-melteigite and ijolite, Foidal syenite and phonolite mark the end phase of ijolitic series and phonolites are the last to be emplaced. Carbonatites include sovitic alvikite and ferro-carbonatite varieties. The suite shows a progressive increase in Al 2 O 3 , Na 2 O and K 2 O and decrease in MgO, CaO, total Iron, MnO and TiO 2 with increasing SiO 2 . Fractional crystallisation has played a dominant role in the evolution of the suite, the major fractional phases being pyroxene and iron oxide mineral.
23 citations
TL;DR: In this paper, the electrical conductivity of polycrystalline lithium-chromium ferrites substituted successively with Ti4+ was studied as a function of composition and temperature, and two different regions with a large variation in activation energies were found.
Abstract: The electrical conductivity of polycrystalline lithium-chromium ferrites substituted successively with Ti4+ was studied as a function of composition and temperature. The resistivity increased with composition and all the samples exhibited a change in slope in the resistivity-temperature curve. Two different regions with a large variation in activation energies were found. The dielectric constant and loss factor for different compositions were measured in the frequency range of 10kHz to 10 MHz. The dielectric permittivity showed a dispersion with frequency for all the samples. Peaks were observed for the samples with 0.4 ⩽ x ⩽ 0.8. The possible mechanisms involved are discussed.
Journal Article•
TL;DR: Calotropin was found to inhibit spermatogenesis in male and induced abortion in pregnant females and reduced protein, sialic acid, and glycogen contents of tests indicate dimished androgenesis.
Abstract: Calotropin isolated and characterized from the roots of Calotropis procera when administered to gerbils (25mg/kg b.wt) and rabbits (25mg; kg b.wt) each day for a period of 30 days inhibited the process of spermatogenesis. The population of spermatids was depleted by 65% and 94% in gerbils and rabbits. The seminiferous tubules and the Leydig cell nuclei diameters were reduced in both the species.The production of mature Leydig cells were decreased by 51.2% and 33.9% in gerbils and rabbits. The number of fibroblast like cells remain unchanged. Reduced protein, sialic acid, and glycogen contents of tests indicate dimished androgenesis. Abortifacient activity was also notived in female rats on the 12(th) day of pregnancy. In conclusion, Calotropin was found to inhibit spermatogenesis in male and induced abortion in pregnant females.
TL;DR: In this article, a plane-symmetric inhomogeneous cosmological model of perfect fluid distribution with electromagnetic field is obtained, where the free gravitational field is Petrov type-II non-degenerate.
Abstract: A plane-symmetric inhomogeneous cosmological model of perfect fluid distribution with electromagnetic field, is obtained.F12 is the non-vanishing component of the electromagnetic field tensor. To get a determinate solution, we assume the free gravitational field is Petrov type-II non-degenerate. In general, the model represents an expanding, shearing, non-rotating universe in which the flow vector is geodetic. The behaviour of the electromagnetic field tensor together with some geometrical and physical aspect of the model are also discussed.
TL;DR: Monitoring of residues of p,p'-DDE, p, p'-DDT alpha-, beta-, gamma-isomers of HCH, aldrin and heptachlor in water, from four different sites of the Mahala water reservoir discovered variations in total organochlorine residue levels attributed to the run-off or subsoil water movement from the catchment area.
TL;DR: The oligospermia achieved was reversible and the hypokalemic response of langurs is similar to human and not related to impurity of the drug.
TL;DR: In this paper, the authors discussed the general features of the multiplicity distributions in relativistic heavy ion collisions and showed that from simple statistical considerations it is possible to predict the dependence of the dispersions of multiplicity distribution on the average multiplicities in any given rapidty wwindow.
TL;DR: In this paper, the effect of concentration and ageing on the molecular complexity of titanium tetraisopropoxide complexes has been evaluated and plausible structures for these complexes have been suggested.
Abstract: Some titanium(IV) complexes of 1,3-dihydro-1,3-dioxo-∝-(substituted)-2H-isoindole-2-acetates, having the general formula where R = hydrogen, methyl, benzyl and isopropyl and -CxHR- = -CHR- or -CH2CHR-; n = 1 or 2), have been synthesized by the reaction of titanium tetraisopropoxide with the corresponding ligands in different stoichiometric ratios. These derivatives have been characterized by elemental analyses, molecular weight measurements and spectral studies (i.r., 1H and 13C NMR). The effect of concentration and ageing on the molecular complexity have been evaluated and plausible structures for these complexes have been suggested.
TL;DR: In this article, it was observed that the amount of hydrogen absorbed increases with the deposition angle which is due to an increase in the porosity of thin films, and the change in resistance value was taken as a measure of the hydrogen absorbed in the samples.
TL;DR: In this article, the average multiplicities of singly charged relativistic particles in oxygen-induced interactions with a nuclear emulsion target are studied over the energy range 2.1-200 A GeV.
Abstract: The average multiplicities of singly charged relativistic particles in oxygen-induced interactions with a nuclear emulsion target are studied over the energy range 2.1–200 A GeV. A similar energy dependence as for proton-induced interactions is observed. Both the number of participating nucleons and the number of binary collisions are shown to be of importance for the particle production.
TL;DR: In this article, the multiplicity distributions of low-energetic target-associated particles from 200 A GeV oxygen-induced interactions with emulsion nuclei are compared with distributions obtained using the Ranft and Fritiof simulation codes.
TL;DR: In this article, the equimolar interaction of the appropriate chlorobimetallic alkoxide of copper(II) with a suitable potassium alkoxometallate has been studied, and new bi-and ter-metallic alkoxides of copper (II) of the types, such as [(ButO)4Al]Cu[M(OPri)x] (3a): M = Al(III), x = 4; 3b-c: M = Nb(V) or Ta(V), x=6); [(But
Abstract: New bi- and ter-metallic alkoxides of copper(II) of the types, [(ButO)4Al]Cu[M(OPri)x] (3a: M = Al(III), x = 4; 3b-c: M = Nb(V) or Ta(V), x=6); [(ButO)4Al]Cu[Zr2(OPri)9] (3d); [(PriO)4Al]Cu[Ta(OPri)6] (4a) and [(PriO)6Nb]Cu[Ta(OPri)6] (4b) have been synthesized by the equimolar interaction of the appropriate chlorobimetallic alkoxide of copper(II) with a suitable potassium alkoxometallate. Methanolysis of (4b) produced [(MeO)6Nb]Cu[Ta(OMe)6] (6). The alcoholysis reactions of (4a) with n-propanol, methanol or tert-butanol gave rise to the products with the composition [(RO)4Al]Cu[Ta(OR)6] (R=Prn (5), Me (9a)), [AlCuTa(OMe)6(OPri)4] (9b) or [(ButO)3(PriO)Al]Cu[Ta(OPri)2
TL;DR: Two benzothiazolines and their corresponding metal complexes were screened for their antifungicidal and antibacterial activity on several fungi and bacteria and found to be quite active in this respect.
TL;DR: In this article, the bonding mode of the ligands with the metal atom is deduced on the basis of i.m.m., 1H n.m, and 13C n.r. spectral studies.
Abstract: The condensation of aldehydes and ketones, 2-pyridine carbaldehyde, 2-thiophene carbaldehyde, 2-furyl aldehyde, 3-indole carbaldehyde, 3-phenylpropane-1-one, 2-propanone, 4-methyl-2-pentane and 2-phenylethane-2-one, with semicarbazide hydrochloride yields the corresponding Schiff bases which, when subsequently reacted with tungsten oxotetrachloride, yield addition products of the type WOCl4·L (L = ligand). The resulting complexes have been characterized by elemental analysis, molecular weight determination, and by conductivity and magnetic measurements. The bonding mode of the ligands with the metal atom is deduced on the basis of i.r.,1H n.m.r. and13C n.m.r. spectral studies.
TL;DR: Blood/serum analysis and haematology of MC-treated langur monkeys revealed that all of the clinically important parameters were well within the normal range and the slightly increased bilirubin concentration and alkaline phosphatase activity returned to normal range within 30 days of the last dose of MC.
Abstract: Malvidin chloride (MC) a colouring agent from flowers of Malvaviscus conzattii Greenum was studied for male anti-fertility effects in adult langur monkeys (Presbytis entellus entellus Dufresne). When fed 50 mg MC kg-1 for a period of 60 days, inhibition of spermatogenesis resulted. The weights of testes and epididymides were reduced and there was atrophy of the Leydig cells. In the epididymis, epithelial cell heights were reduced after MC-treatment. Conspicuous shrinkage of seminiferous tubules and Leydig cell nuclei were evident. Depletion of total proteins, RNA, sialic acid, alkaline/acid phosphatase activity in testes and epididymides with the elevation of testicular levels of cholesterol and glycogen also occurred. Blood/serum analysis and haematology of MC-treated langur monkeys revealed that all of the clinically important parameters were well within the normal range. The slightly increased bilirubin concentration and alkaline phosphatase activity returned to normal range within 30 days of the last dose of MC. The anti-spermatogenic activity of MC in langur monkeys is discussed.
TL;DR: In this paper, the trigonal bipyramidal and octahedral geometries for organolead IV complexes derived from biologically active sulfur and nitrogen donor ligands have been proposed on the basis of electronic, infrared and NMR spectral evidences.
Abstract: Some organolead(IV) complexes derived from biologically active sulfur and nitrogen donor ligands have been synthesized and characterized by elemental analyses, molecular weight determinations and conductivity measurements. The trigonal bipyramidal and octahedral geometries for these complexes have been proposed on the basis of electronic, infrared and NMR (1H and 13C) spectral evidences. The antifungal activity of some of the ligands and their complexes have also been evaluated against Fursarium oxysporum SCW. ex Frics f. sp. Ciceri (Pedwick) subram.
TL;DR: In this paper, the motion of effective atoms in liquid Na 0.5K0.5 alloy in terms of velocity autocorrelation function, power spectrum, and mean square displacement analogous to the single particle motion in liquid metals employing the model developed by Glass and Rice in quasi crystalline approximation.
Abstract: An effort is made to study the motion of effective atoms in liquid Na0.5K0.5 alloy in terms of velocity autocorrelation function, power spectrum, and mean square displacement analogous to the single particle motion in liquid metals employing the model developed by Glass and Rice in quasi crystalline approximation. The motions of effective atoms are also studied through the collective excitations by computing the longitudinal and transverse phonon frequencies. The results of collective excitations are in good agreement with the molecular dynamics (MD) results. Besides, results of thermodynamical properties such as isothermal bulk modulus and Debye temperature are also presented. The computed values are in good agreement with the results obtained by other theoretical calculations.
Es werden Anstrengungen unternommen, um die Bewegung von effektiven Atomen in flussigen Na0.5K0.5-Legierungen mittels Geschwindigkeits-Autokorrelationsfunktion, Leistungsspektrum und mittleren Verschiebungen in Analogie zur Einpartikelbewegung in flussigen Metallen zu untersuchen, wobei das Modell von Glass und Rice in Quasikristallnaherung benutzt wird. Die Bewegungen der effektiven Atome werden auch mit kollektiven Anregungen durch Berechnung der longitudinalen und transversalen Phononfrequenzen untersucht. Die Ergebnisse der kollektiven Anregungen sind in guter Ubereinstimmung mit Ergebnissen der Molekulardynamik (MD). Daruberhinaus werden die thermo-dynamischen Eigenschaften, wie isothermer Elastizitatsmodul und Debye-Temperatur, ebenfalls angegeben. Die berechneten Werte sind in guter Ubereinstimmung mit den Ergebnissen, die durch andere theoretische Berechnungen erhalten werden.
TL;DR: Wogonin, a mild oestrogenic compound, exhibited interceptory activity at all the stages of pregnancy and interfered with normal development of the embryos which resulted in the resorption of foetuses.
Abstract: Wogonin, 5,7-dihydroxy-8-methoxyflavone, extracted from Holmskioldia sanguinea Retz. has been tested for oestrogenic and anti-implantational activities in the rat. Wogonin displayed mild oestrogenic but effective anti-implantational activities. In the three days uterotrophic bioassay, at a dose level of 10 mg/kg body weight per day, intramuscularly, the wet uterine and vaginal weights increased significantly. Wogonin at the same dose level when given intramuscularly from days 1–3, 4–6, 1–7 post coitum and orally from days 1–7 post coitum effectively inhibited implantation. However, when the drug was administered from days 7–9 post coitum, it did not affect the implantation, but interfered with normal development of the embryos which resulted in the resorption of foetuses. Wogonin, a mild oestrogenic compound, exhibited interceptory activity at all the stages of pregnancy.
TL;DR: In this article, the authors derived a number of interesting expressions for the composition of certain multidimensional fractional integral operators involving a general class of polynomials with essentially arbitrary coefficients.
TL;DR: In this article, the authors observed that the oxidation of formic acid with chloramine-T has been observed to occur via two paths, one dependent and other independent of hydrogen ion concentration, and that the reaction is also retarded by toluene-p-sulphonamide, one of the reaction products.