1903-1999

Permanent URI for this collectionhttps://dl.bhu.ac.in/bhuir/handle/123456789/51611

Browse

Now showing 1 - 20 of 10442

1 (2)gl gene regulates late expression of segment polarity genes in Drosophila
(1995) Ashim Mukherjee; S.C. Lakhotia; J.K. Roy
To analyse the possible roles of Drosophila tumour suppressor genes, 1 (2)gl and 1 (2)gd, in differentiation programmes of imaginal cells, we investigated their interactions with two segment polarity genes, viz., cubitus interruptus Dominant (ci-D) and engrailed (en), by examining their patterns of expression in tumourous imaginal discs of 1 (2)gl4 or 1 (2)gd1 homozygous larvae. While the 1 (2)gd1 mutation did not have much effect, the areas of expression of ci-D and en in the tumourous discs of 1 (2)gl homozygous larvae were significantly increased and the anterior-posterior compartment boundary was no longer identifiable. To examine if the loss of en expression compartment boundary in 1 (2)gl tumourous discs was due to overproliferation of the posterior compartment cells or due to a deregulated expression of en in the anterior compartment cells, 1 (2)gl4 homozygous cell clones were generated in 1 (2)gl4 enlacZ/++ background. A distinct X-gal staining in 1 (2)gl homozygous clones in the anterior compartment in wing imaginal discs or in adult wings confirmed deregulated ectopic expression of en in 1 (2)gl mutant anterior compartment cells. We suggest that 1 (2)gl is involved in regulating post embryonic expression of segment polarity genes. © 1995.
1, 1-Dithiolato-bridged heterobimetallic complexes containing a transition metal ion and oxouranium(VI)
(Kluwer Academic Publishers, 1990) Nanhai Singh; Nand K. Singh; Prahlad P. Agrawal
Anionic complexes [UO2(1, 1-dithiolate)2]2- interact strongly with transition metal ions to yield a new class of dithiolato-bridged heterobimetallic complexes MUO2(1, 1-dithiolate)2 (M=CoII, NiII, CuII, ZnII or PbII, 1, 1-dithiolate = isomaleonitrile dithiolate (i-MNT2-) and trithiocarbonate (CS32-)). (Et4N)2[UO2(i-MNT)2] and (Et4N)2[UO2(CS3)2] have also been prepared. The complexes have been characterized by elemental analysis, i.r., u.v.-vis. and e.s.r. spectral studies. The heterobimetallic complexes are non-electrolytic, whereas (Et4N)2-[UO2 (i-MNT)2] and (Et4N)2[UO2(CS3)2] are 2:1 electrolytes. The i.r. data indicate symmetrical bidentate bridging behaviour for the dithiolate ligands. Magnetic moments, electronic spectra and e.s.r. studies are commensurate with a square planar environment around CoII, NiII and CuII. © 1990 Chapman and Hall Ltd.
1, 3-Propanediamine, 1, 4-butanediamine (putrescine) and 1, 5-pentanediamine (cadaverine) complexes with zinc(ii), cadmium(ii) and mercury(ii) halides and pseudohalides
(1975) I.S. Ahuja; Raghuvir Singh
Coordination compounds formed by zinc(II), cadmium(II) and mercury(II) halides and pseudohalides with 1, 3-propane diamine, 1, 4-butanediamine (putrescine) and 1, 5-pentanediamine (cadaverine) have been prepared and characterized by molecular conductance and infrared spectral measurements down to 200 cm-1. Possible structures for these complexes in the solid state are discussed. © 1975, Taylor & Francis Group, LLC. All rights reserved.
1,10-Phenanthroline complexes of some uranyl salts
(1973) I.S. Ahuja; Rajindar Singh
[No abstract available]
1,2,3-Trioxygenated glucosyloxyxanthones from Polygala triphylla
(1981) Shibnath Ghosal; Prasad C. Basumatari; Shanta Banerjee
Four B-ring oxygen-free trioxygenated xanthones, viz. 1-OH-2,3-(OMe)2-, 1,2,3-(OMe)3-, 1-OH-2,3- (OCH2O)-, 1-OMe-2,3-(OCH2O)-xanthone, two B-ring oxygen-free glucosyloxyxanthones, viz. 1-O-gl.-2-OH-3-OMe- and 1-O-gl.-2,3-(OCH20)-xanthone, and a pentaoxygenated xanthone, 1-OMe-2,3,6,7-(OCH2O)2-xanthone, have been isolated from the flowering top of Polygala triphylla. The xanthones have been characterized on the basis of chemical transformation, comprehensive spectral evidence, and by direct comparison where possible. This is the first report of occurrence of the glucosyloxyxanthones in nature. The biochemical significance of these chemical characters in higher plants is appraised. © 1981.
1,3(n-π*) excited states of benzaldehyde
(Springer India, 1985) R.D. Tewari; P.C. Mishra
Geometries of the first triplet and first singlet n-π* excited states of benzaldehyde have been optimized using the sindo 1 molecular orbital wave-function (with CI) and the Newton-Raphson method. The triplet excited state geometry of the molecule is found to be appreciably non-planar whereas that of the singlet excited state is planar. A crossing of molecular orbitals occurs in going from the ground state equilibrium geometry to the triplet and singlet n-π* excited state equilibrium geometries. Existence of the para-directing effect of the singlet n-π* transition for electronic charges found in an earlier work is confirmed by the present work. The triplet n-π* excitation rearranges electronic charges mainly on the CHO group. It is found that the dipole moment of the molecule would appreciably increase following the singlet n-π* excitation whereas the same would appreciably decrease following the triplet n-π* excitation. © 1985 Indian Academy of Sciences.
1,3,4-Thiadiazoles as potential EP additives - a tribological evaluation using a four-ball test
(1995) A. Bhattacharya; T. Singh; V.K. Verma; N. Prasad
This paper reports a comparative study of the wear-reducing efficiency and extreme pressure properties of 0.5% ( w v) admixtures of paraffin oil and 2-amino-5-arylamino-1,3,4-thiadiazole additives and a commercial sulphur-phosphorus additive in a four-ball test. 2-Amino-5-p-Cl-phenylamino-1,3,4-thiadiazole additive shows excellent EP properties as is evident from the surface smoothness of SEM micrographs. The tribochemistry of the wear-scar surface has been investigated by the auger electron spectroscopy (AES) technique. © 1995.
1,3-bis(4-pyndyl)propane complexes of divalent metal halides and pseudohalides
(Kluwer Academic Publishers, 1978) Ishar Singh Ahuja; Raghuvir Singh; Chandra Pati Rai
Coordination compounds formed by the interaction of 1,3-bis(4-pyridyl)propane (DPP) with some divalent metal halides and pseudohalides have been prepared and characterized by magnetic susceptibilities, electronic and i.r. spectral measurements down to 200 cm-1 in the solid state. The i.r. spectra indicate that DPP acts mostly as a bidentate bridging ligand in these complexes. Moreover, the two pyridyl rings which are nonplanar in uncoordinated DPP become coplanar upon coordination. Tentative stereo chemistries of the complexes have been suggested in the solid state. The ligand field parameters Dq, B, β, λ and ν2/ν1 have been calculated for the cobalt(II) and nickel(II) complexes and are consistent with the proposed stereo chemistries. © 1979 Verlag Chemie, GmbH.
1,3-di-(4-pyridyl)propane complexes with some uranyl salts
(1976) I.S. Ahuja; Raghuvir Singh
[No abstract available]
1,3-Dipolar cycloaddition of diphenyl nitrile imine with 4-arylmethylene-2,4-dihydro-5-methyl-2-phenyl/phenylmethyl-3H-pyrazol- 3-ones
(1991) D. Singh
[No abstract available]
1‐Aryl‐2‐amino/hydrazino‐4‐phenyl‐1,6‐dihydro‐1,3,5‐triazine‐6‐thione and Related Thiocarbamides/Thiosemicarbazides as Antithyroidal Agents
(1993) R. Prasad; P.K. Srivastava
Different 1‐aryl‐2‐benzylmercapto‐4‐phenyl‐1,6‐dihydro‐1,3,5‐triazine‐6‐thiones have been synthesized by known methods. These triazines on treatment with ammonia/hydrazine hydrate afforded the corresponding 1‐aryl‐2‐amino/hydrazino‐4‐phenyl‐1,6‐dihydro‐1,3,5‐triazine‐6‐thiones which on treatment with arylisothiocyanates afforded the related thiocarbamides/thiosemicarbazides. Some of these compounds show appreciable antithyroidal activity. Copyright © 1993 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim
1.66-Ga-old metamorphosed Pb-Cu deposit in Sargipali (eastern India) : Manifestations of tidal flat environment and sedex-type genesis
(Elsevier B.V., 1996) Rajesh K. Vishwakarma
The metasedimentary rocks and the unusual Pb-Cu mineralization of the Sargipali mine area are described and discussed to elucidate the processes involved in their deposition. Important lines of evidences used for the interpretation of an inter- to supratidal flat environment are: (1) a general pattern of a shallowing upward sequence from coarse clastics (arenaceous) through finer clastics (argillaceous) to carbonate; (2) the occurrence of metaconglomerate, trough cross-bedding and wave-ripples (within the arenaceous lithostratigraphic unit); (3) intercalations of quartzite, carbonate skarn, dolomite, and convolution of chert laminae (within the argillaceous lithostratigraphic unit); and (4) intercalation of quartz-mica-chlorite schist laminae (within the carbonate lithostratigraphic unit). The ores seems to belong to the same environment. Furthermore, in the assessment of the origin of the Sargipali ores, it is recognized that the orebodies not only represent a sedimentary setting, but also show a high Pb-content, and an older age of mineralization than that of deformation, metamorphism and granite intrusion. Along with the lack of stockwork zones, wall rock alteration, subaerial volcanism, and the presence of chert and tourmalinite, these features are consistent with a sedex-type origin. The idea of this origin finds support by yet another observation, i.e., the ore sulphur was mainly derived from the inorganic reduction of the seawater sulphate (at more than 300°C), while the ore metals were leached from the μ (= 238U/204Pb) - enriched Singhbhum soda-granite of 2200 Ma. The present study may help in conceiving a 'new' possibility that the sediment-hosted Pb-rich deposits of MVT origin can also be evaluated in terms of the sedex model.
131I profile scan in different human constitutions by whole body counter
(1978) G.P. Dubey; S. Agrawal; K.N. Udupa
[No abstract available]
16th annual general meeting
(1951) H.N. Roy
[No abstract available]
1H NMR spectral evidence for the chair conformation in mono- and bis-(dioxouranium(VI)) complexes of bis(o-hydroxynaphthaldehyde)-oxaloyldihydrazone
(1994) Ram A. Lal; Alaknanda N. Siva; Lalit M. Mukherjee; Ram K. Thapa; Krishan K. Narang; Meena K. Singh
[No abstract available]
2 Substituted acetamido α naphtho (2,1 d) thiazole as local anaesthetics
(1974) P.N. Bhargava; I.C. Tiwari
[No abstract available]
2′, 3′-cyclic neucleotide 3′-phosphodiesterase activity in developing rat brain
(1998) Ritu Singh; R. Shankar
[No abstract available]
2,2′-bipyridine complexes with some uranyl salts
(1973) I.S Ahuja; Rajindar Singh
[No abstract available]
2,2′-Bipyridine N,N′-dioxide complexes with cobalt (II), nickel (II), zinc (II), cadmium (II) and mercury (II) thiocyanates
(1974) I.S. Aruja; Raghuvir Singh
Coodination compounds formed by cobalt (II), nickel (II), zinc (II), cadmium (II) and mercury(II) thiocyanates with 2,2′-bipyridine N,N′-dioxide have been prepared and characterized by molecule conductance, magnetic moments, electronic and infrared spectral measurements down to 200 cm-1 as well as by X-ray powder patterns in the solid state. Possible coordination arrangement of the ligands around the metal atoms in these compounds has been discussed. © 1974.
2,2'-Bipyridine N,N'-dioxide complexes with some uranyl salts
(1973) I.S. Ahüja; Rajindar Singh
Coordination compounds formed by uranyl chloride, sulphate, nitrate and thio-cyanate with 2,2'-Ripyridine N,N'-dioxide have been prepared and characterized by infrared spectral measurements down to 200 cm-1 in the solid state. Possible coordination arrangement around the uranyl group in these complexes has Reen discussed. © 1973.