Showing papers by "University of Rajasthan published in 1988"
TL;DR: A brief account of the methods generally employed for the synthesis of metal alkoxides has been presented in this article, followed by an extension of the work to a novel series of ter- and tetra-metallic alkoxide during the last two years.
Abstract: A brief account of the methods generally employed for the synthesis of metal alkoxides has been presented. Successful elucidation of the structural features of simple alkoxides on the basis of a coordination model involving alkoxy bridges has prompted a detailed study of a variety of bimetallic alkoxides during the last two decades followed by the extension of the work to a novel series of ter- and tetra-metallic alkoxides during the last two years. Most of these polymetallic alkoxides (including derivatives of strongly electropositive alkali, alkaline earth metals and lanthanons) are stable to heat and can be volatilized unchanged. After listing the typical properties and reactions of these alkoxy derivatives, their hydrolytic reactions are briefly discussed. The uses of metallic alkoxides for ceramic materials and the potential applications of bimetallic alkoxides in this direction are discussed.
156 citations
TL;DR: An ethanolic extract of the flowers of Calotropis procera was investigated for anti-inflammatory, antipyretic, analgesic and antimicrobial activities and showed some weak effect in rats on the writhing induced by acetic acid.
92 citations
TL;DR: Various medicinal plants and plant components, which are being used as anticonvulsant and antiepileptic, are discussed.
75 citations
Journal Article•
TL;DR: Fifty per cent ethanolic extract of Curcuma longa (tuber) and Nardostachys jatamansi (whole plant) feeding elevates HDL-cholesterol/total cholesterol ratio and causes a significant reduction in the ratio of total cholesterol/phospholipids.
Abstract: Fifty per cent ethanolic extract of Curcuma longa (tuber) and Nardostachys jatamansi (whole plant) feeding elevates HDL-cholesterol/total cholesterol ratio. The extracts also caused a significant reduction in the ratio of total cholesterol/phospholipids. Curcuma longa exhibited better cholesterol and triglyceride lowering activity [Ch = -85%; Tg = -88%] as compared to N. jatamansi in triton-induced hyperlipidaemic rats. In view of the protective action of HDL against heart disease and atherogenecity, C. longa consumption is recommended.
69 citations
TL;DR: In this article, an experiment in which emulsion chambers were exposed to a beam of 200 A GeV 16 O at the CERN SPS was reported, where pseudo-rapidity distributions were measured with high precision.
68 citations
TL;DR: In this paper, the incorporation of hydrogen into thin film form discussed in this article is a relatively new field of research and the main advantages of thin film metal hydrides are that these provide large surface area with fast charging discharging rate for hydrogen, pulverization is slower, both critical pressure and critical temperature are significantly lower, better heat transfer arrangements, protective surface coating could be done to stop poisoning by oxygen and activation of thin-film hydride is possible by coating with a layer of catalytic material.
45 citations
41 citations
TL;DR: In this paper, Me2SiL2 complexes have been characterized by elemental analysis, molecular weight determinations and conductivity measurements, and structures have been proposed using electronic, IR, 1H NMR and 13C NMR spectral studies.
38 citations
TL;DR: In this article, an analytical theory has been developed for the light emission of a reverse-biased silicon p-n junction based on the theory of ionization and indirect recombination of electrons and holes under high-field conditions, the relative intensity of emitted light has been derived.
Abstract: An analytical theory has been developed for the light emission of a reverse-biased silicon p-n junction. Based on the theory of ionization and indirect recombination of electrons and holes under high-field conditions, the relative intensity of emitted light has been derived. It is observed that the normalized results of intensity are in good agreement with the experimental results for an electron ionization length l ioe = 60 A , and a hole ionization length l ioh = 70 A . Thus it confirms the validity of this theoretical model for light emission in a reverse-biased silicon p-n junction.
34 citations
TL;DR: A comment by Miller was published in the August 1989 issue of Environment and Planning A, which makes an intriguing comparison of a paper by Chen and Rose with one by Miller.
Abstract: A comment by Miller was published in the August 1989 issue of Environment and Planning A, which makes an intriguing comparison of a paper by Chen and Rose with one by myself. His comment concerns the uses of various terminologies in the literature on supply-driven and demand-driven input—output models and the claims to have defined terms such as ‘stability’, ‘joint stability’, and ‘consistency’. Further, generalizations are made on the basis of a specific set of aggregated data for the US economy to show that biproportional changes suggested in my theorem are unlikely to be observed in the real world. I will show that Miller adds no illumination to the issues of ‘stability’ or ‘consistency’, and that, in fact, his comment accomplishes nothing of import. His comment could also leave us with the impression that the USA is the only ‘real-world’ example worthy of comment.
27 citations
TL;DR: In this paper, the synthesis and structural features of some trigonal bipyramidal and octahedral complexes of silicon(IV) with biologically active benzothiazolines are described.
TL;DR: It is concluded that hypercholesteromia affects the testicular function and aortic endothelium and three- and sevenfold increases were noticed in the serum cholesterol levels of rats and rabbits.
Abstract: Cholesterol fed to male rats and rabbits for 120 days impaired testicular function The production of secondary spermatocytes in rats and rabbits was reduced by 261% and 469%, respectively There was significant reduction in spermatid cell population, seminiferous tubules, and Leydig's cell nuclear dimensions In rats aortic endothelium showed some alterations while in rabbits full-blown atherosclerotic plaque containing a necrotic core and a proliferative fibrous cap was found Total cholesterol, triglycerides and phospholipids of the testes were increased whereas, testicular glycogen was significantly reduced Three- and sevenfold increases were noticed in the serum cholesterol levels of rats and rabbits The LDL cholesterol values were increased while the HDL cholesterol/Total cholesterol ratio was significantly decreased (P less than 0001) It is concluded that hypercholesterolemia affects the testicular function and aortic endothelium
TL;DR: Analytical expressions for the dispersion of the longitudinal and transverse phonons are obtained for a two-component metallic glass employing a self-consistent phonon theory for amorphous solids as developed by Takeno et al.
Abstract: Analytical expressions for the dispersion of the longitudinal and transverse phonons are obtained for a two-component metallic glass employing a self-consistent phonon theory for amorphous solids as developed by Takeno et al. The effective pair potential used for the computation of the eigenfrequencies of the longitudinal and transverse phonons in ${\mathrm{Ca}}_{70}$${\mathrm{Mg}}_{30}$ glass is obtained by making use of the Ashcroft pseudopotential for the pure components. Eigenfrequency expressions reproduce the main characteristic features of the dispersion curves obtained by neutron scattering and computer simulation techniques, both for the longitudinal and the transverse phonons. The results of the present computations are in good agreement with the available experimental data.
TL;DR: In this paper, the formation of new chemical bonds between different alkoxides employed in the starting mixed solution has been envisaged, although the actual isolation of a large variety of polymetallic alkoxide in our laboratories has given an entirely new turn to the expectations (e.g., preparation of spinel from magnesium bis-tetraalkoxyaluminates) from this process.
Abstract: Beginning with the work of Dislich, metal alkoxides have been increasingly used for the preparation of oxide-ceramics by the ‘sol-gel’ process. In spite of higher initial cost of alkoxides, their main advantages are (i)homoge-neous mixing at molecular level in the initial solution; (ii)ease of hydrolysis; and (iii) lower sintering temperatures. Although the formation of new chemical bonds between different alkoxides employed in the starting mixed solution has been envisaged, the actual isolation of a large variety of polymetallic alkoxides in our laboratories has given an entirely new turn to the expectations (e.g., preparation of spinel from magnesium bis-tetraalkoxyaluminates) from this process. Some such possibilities are being presented for synthesis of novel ceramic materials. Reactions of polymetallic alkoxides with water, alcohols andβ-diketones would be discussed to throw light on their hydrolysis process in the presence of other alcohols and chelating ligands.
Journal Article•
TL;DR: In this paper, the authors show that the Vaikrita Group exhibits extremely intricate internal deformation resulting from polyphasal folding and repeated transposition of foliation planes, and the bulk non-coaxial strain in the rocks is attributable to the variation in the case of slip on the shear planes during thrust propagation.
Abstract: The so-called 'Central Crystallines' building the bulk of the Great Himalaya (=Himadri) comprise two major tectonic units. The upper unit is constituted of highgrade psammitic metamorphics associated with anatectic granites of the Vaikrita Group, and the lower unit is made up of Precambrian granites, gneisses, amphibolites, meta-sediments and their mylonitic equivalents recognized as the Munsiari Formation. The Vaikrita Group makes a huge lithotectonic slab bounded by moderately inclined Main Central (Vaikrita) Thrust in the south and the steeply dipping Trans-Himadri (Malari) Thrust in the north. Sandwiched between the Munsiari and the Main Central (Vaikrita) Thrusts, the Munsiari is a severely tectonized and drastically condensed lithotectonic sheet representing the root zone of the Lesser Himalayan crystalline nappes. In small-scale, the Vaikrita shows extremely intricate internal deformation resulting from polyphasal folding and repeated transposition of foliation planes. The bulk non-coaxial strain in the rocks is attributable to the variation in the case of slip on the shear planes during thrust propagation. The period of thrusting is coeval with the main phase of progressive metamorphism, anatexis and attendant granite emplacement during the late Eocene to Lower Miocene period. Later deformation and retrogressive metamorphism are related to the uplift during the Middle and Upper Miocene, culminating in the Middle Pleistocene, when the Vaikrita rocks were brought to a brittle field of deformation from the earlier ductile and brittle-ductile fields. The Vaikrita exhibits an abrupt rise in the grade of metamorphism to sillimanite zone of progressive (Barrovian type) metamorphism from a very low to medium grade of (Himalayan) metamorphism in the Munsiari. In the deeper level (∼30 km), the Vaikrita rocks underwent progressive regional metamorphism and anatexis that gave rise to granites, which extensively invaded the metamorphics. The episodic uplift of the Vaikrita Group was due to the shifting of thrust movements by relay from the Main Central (Vaikrita) Thrust, to the Munsiari Thrust and the other minor thrusts of the schuppen zone in the south. A part of the uplift can be attributed to the diapiric rise of the anatectic granites.
TL;DR: It is suggested that maximum cornification, vaginal temperature nadir and serum sialic acid peak could be used as markers for prediction and detection of the time of ovulation in langur monkeys.
Abstract: In 5 caged langurs menstrual cycle length (for 125 cycles) varied from 18 to 45 days with a mean +/- s.d. of 26.3 +/- 3.6 days. Menstruation lasted for 2 days. A distinct cycle of vaginal smear cells was observed with a maximum cornification on Day 10 coinciding with the serum oestradiol peak. A monophasic pattern of vaginal temperature with a significant nadir on Day 11, 1 day after the oestradiol peak, was observed. Serum sialic acid concentrations directly reflected the oestrogenic activity and showed a significant peak on Day 10, coinciding with the oestradiol peak and was followed by a progesterone rise. Langurs menstruated throughout the year without showing any sign of summer amenorrhoea. We suggest that maximum cornification, vaginal temperature nadir and serum sialic acid peak could be used as markers for prediction and detection of the time of ovulation in langur monkeys.
TL;DR: The electron-momentum distribution in hexagonal-close-packed zirconium has been studied for the first time with use of a Compton-scattering technique and best agreement between theory and experiment is found if the electron configuration is chosen as 4d-5s.
Abstract: The electron-momentum distribution in hexagonal-close-packed zirconium has been studied for the first time with use of a Compton-scattering technique. Measurements have been made by scattering 59.54-keV \ensuremath{\gamma} rays. Theoretical computations have been carried out with use of the renormalized-free-atom model for various 4d-5s configurations. Best agreement between theory and experiment is found if the electron configuration is chosen as 4${d}^{3}$5${s}^{1}$.
TL;DR: Two cylindrically-symmetric cosmological models representing viscous fluid distributions when free-gravitational field of typeD where coefficient of shear viscosity is assumed to be proportional to the rate of expansion, are obtained in this article.
Abstract: Two cylindrically-symmetric cosmological models representing viscous fluid distributions when free-gravitational field of typeD where coefficient of shear viscosity is assumed to be proportional to the rate of expansion, are obtained. The behaviour of the models in the absence of viscosity and other physical properties are also discussed.
TL;DR: In this paper, an ion-acoustic soliton in an ionbeam plasma system was studied using the renormalization procedure of Kodama and Taniuti in the reductive perturbation method and an alternative meth-merchant method.
Abstract: Propagation of an ion-acoustic soliton in an ion-beam plasma system is studied using the renormalization procedure of Kodama and Taniuti in the reductive perturbation method and an alternative meth...
TL;DR: In this paper, the coordination behavior of Schiff bases derived from the condensation of some of the heterocyclic aldehydes with hydrazine hydrate, towards FeII, PdII and PtII, has been studied.
Abstract: The coordination behaviour of Schiff bases derived from the condensation of some of the heterocyclic aldehydes with hydrazine hydrate, towards FeII, PdII and PtII, has been studied. The 1:1 and 1:2 molar reactions of MCl2 with the Schiff bases result in coloured solids which have been characterised by elemental analysis, conductance and magnetic measurements. The mode of bonding has been deduced from i.r. and n.m.r. (1H and13C) studies.
TL;DR: In this paper, the reaction of 2-hydrazinobenzimidazoles with β-diketones in neutral and acidic media revealed that 2-(3,5-disubstituted-1H-pyrazol-1-yi)benzimidaxoles are formed in the former case, whereas hydrazones are obtained in acidic medium.
TL;DR: In this paper, the synthesis of chloride bimetallic isopropoxides of copper(II) has been described. But the synthesis was performed in the context of the first-order synthesis of new bi-and ter-metallic alkoxides.
TL;DR: In this article, an octahedral geometry withcis-MoO2 is proposed, and six-coordinate dioxomolybdenum (VI) complexes of the type [MoO 2(SCZ)2] (HSCZ=semicarbazone) were obtained by elemental analyses, molecular weight determinations and conductance and magnetic measurements.
Abstract: Six-coordinate dioxomolybdenum(VI) complexes of the type [MoO2(SCZ)2] (HSCZ=semicarbazone) were prepared and characterized by elemental analyses, molecular weight determinations and conductance and magnetic measurements. On the basis of electronic, i.r., proton magnetic resonance, and13C nuclear magnetic resonance spectral studies, an octahedral geometry withcis-MoO2 is proposed.
TL;DR: In this paper, the chlorine in these chloride bimetallic isopropoxides has been replaced with alkoxide groups by their reactions with potassium alkoxides yielding products of the types, [(OR)Co{Ta(OPr i ) 6 }] and [(OR]Co{Zr 2 (OPr I ) 9 }] (R=Me, Pr n, Pr i, Pr i, Bu n, Bu s or Bu t ).
TL;DR: Saussurea candicans afforded three new highly oxygenated guaianolides along with several known guanolides by high field 1 H NMR spectroscopic methods as mentioned in this paper.
TL;DR: In this article, the reaction of 2-amino-3-cyano-4,6- disubstituted-pyridines with various arylisothiocyanates has been characterised by elemental analysis, IR, 1H and 19F NMR spectral studies.
TL;DR: One cm long hypocotyl explants of Dalbergia sissoo produced shoot buds when cultured on Murashige and Skoog (MS) medium containing BAP + IAA/IBA/NAA, or IBA + NAA combination.
TL;DR: Various fractions of Verbesina encelioides have demonstrated significant antibacterial, antifungal, antiviral, antitumor, hypoglycaemic and anti‐implantation activities.
Abstract: Various fractions of Verbesina encelioides have demonstrated significant antibacterial, antifungal, antiviral, antitumor, hypoglycaemic and anti-implantation activities.
TL;DR: The experimental Compton profile of polycrystalline tungsten is reported and the band-structure calculation of Papanicolaou et al. is compared with the calculation based on the renormalized-free-atom model with different 5d-6s configurations.
Abstract: In this paper we report the experimental Compton profile of polycrystalline tungsten. The measurements have been made by scattering 59.54-keV ..gamma.. rays and are compared with the band-structure calculation of Papanicolaou et al. These results have also been compared with our calculation based on the renormalized-free-atom model with different 5d-6s configurations. Best agreement with experiment is found for the 5d/sup 5.4/6s/sup 0.6/ electron configuration.