Showing papers by "National Chemical Laboratory published in 1969"
41 citations
TL;DR: In this article, a new primary lac acid (lacojalaric arid) is described, which belongs to the cedrene group of sesquiterpenoids and a direct chemical correlation of this acid with (−)-α-cedrene has also been accomplished.
27 citations
TL;DR: A new method for quantitative estimation of extent of grafting on cellulose was developed and its validity was established and the grafted samples with 20% increase in weight were found to be highly resistant to microorganisms.
Abstract: Acrylonitrile was grafted onto cellulose with the use of ceric salt as initiator and the grafting was found to be maximum at 0.6N acid concentration. The effect of monomer and initiator concentration on the extent of grafting was studied. A new method for quantitative estimation of extent of grafting on cellulose was developed and its validity was established. The grafted samples with 20% increase in weight were found to be highly resistant to microorganisms.
26 citations
TL;DR: In this article, the spectra of a few mono and disubstituted ureas have been analyzed and the characteristic bands due to the carbonyl and amino groups have been assigned with the help of their deuterated analogues.
25 citations
TL;DR: In this article, the electric field gradients in normal spinels were investigated and the authors showed that the gradient of the field is linear in the number of spinels in the spinels.
Abstract: (1969). Electric field gradients in normal spinels. Molecular Physics: Vol. 16, No. 6, pp. 625-626.
19 citations
TL;DR: In this paper, the formation constants, enthalpy and entropy changes for bis-histidino complexes of Mn(II), Fe, Co, Ni, Cu, and Zn(II) ions have been determined.
16 citations
TL;DR: Using a selective catalyst consisting of molybdenum oxide doped with tungstic oxide on alumina, the kinetics of the vapour-phase oxidation of toluene by air has been studied as mentioned in this paper.
12 citations
TL;DR: In this article, a bridged sulfonium ion A with a predictable steric configuration has been proposed for 3,4-dimethyl-Δ3-thiachromene.
11 citations
TL;DR: In this paper, the stereochemistry of lyratol and the structure of its reduction products were deduced from a study of their NMR spectra, which confirmed the modified isoprenoid structure.
9 citations
9 citations
TL;DR: In this article, an attempt has been made to correlate the fragmentation modes and structure of costunolide and some lactones derived from it, containing a ten-membered carbocyclic system.
Abstract: An attempt has been made to correlate the fragmentation modes and structure of costunolide and some lactones derived from it, containing a ten-membered carbocyclic system. The possible origins for the major fragments have been determined, using high resolution mass spectrometry and deuterium labelling.
TL;DR: In this article, electron diffraction of vacuum deposited films of ZnTe and ZnSe grown on different faces of rocksalts, cleavage face of mica and also on amorphous substrates at various substrate temperatures have been studied.
TL;DR: In this article, surface potentials of monomolecular films of n-long chain alcohols were measured by the ionizing electrode method between 14°C and 25°C as a function of surface pressure (π) and area/molecule (A).
TL;DR: In this paper, weakly basic anion exchangers have been investigated for the selective uptake of cations, and tetraethylene pentamine resin has been used to absorb copper, nickel and cobalt at different pH levels.
Abstract: Two weakly basic anion exchangers have been investigated for the selective uptake of cations. The cashewnut- shell liquid - tetraethylene pentamine resin absorbs copper, nickel and cobalt at different pH of external solution. The unbuffered melamine-based resin was specific for copper, which could be separated from nickel and cobalt completely.
TL;DR: In this article, a linear dependence of rate of polymerization on the monomer and catalyst concentrations as well as an overall activation energy of 5.87 kcal/mole were found.
Abstract: Kinetics of the polymerization of methyl methacrylate with the VOCl3AlEt3 catalyst system at 40°C in n-hexane have been studied. A linear dependence of rate of polymerization on the monomer and catalyst concentrations as well as an overall activation energy of 5.87 kcal/mole were found. Characterization of the structure of the polymer by NMR spectra revealed the presence of stereoblock units. The mechanism of polymerization is discussed in relation to the kinetic data obtained.
TL;DR: The surface viscosities on a water surface, of mixed monolayers of n-long chain alcohols and n-alkoxy ethanols (Cn-OC2H4OH), were studied as a function of surface pressure (2-40 dynes/cm) and shear rate (012-18 sec-1) for three different compositions, with a rotational viscometer.
TL;DR: The Mossbauer spectra of bis-dithioacetylacetone tetrachloro ferrate (II) and tetramethyl ammonium (TAM) were found to be consistent with the tetrahedral coordination of FeII ion to 4 Cl− anions as mentioned in this paper.
TL;DR: An electron diffraction study was made on the growth of Tl2Se and tl2Te films on collodion as well as on the cleavage face of rocksalt at different substrate temperatures as discussed by the authors.
TL;DR: The synthesis of tris-(p-isocyanato phenyl) cyanurate was described in this article, where the isocyanate groups directly attached to the carbon atoms of the sym-triazine ring were stable.
Abstract: The synthesis of tris-(p-isocyanato phenyl) cyanurate is described. Unlike the isocyanate groups directly attached to the carbon atoms of the sym-triazine ring the isocyanate groups in the compound synthesized are stable.
Die Synthese von Cyanursaure-tris-[p-isocyanato-phenylester] wird beschrieben. Zum Unterschied von den Isocyansaureresten, die direkt an die Kohlenstoffatome des sym-Triazinrings angelagert sind, sind die Isocyansaurereste in der synthetisierten Verbindung stabil.
TL;DR: In this article, the Mossbauer spectra of sources of 57 Co in the form of spinels Co [Cr 2 ] O 4 and Co S 4 matched against a 92 per cent 57 Fe-enriched K 4 Fe(CN) 6. 3H 2 O absorber have been studied from −80°C to 362°C.
TL;DR: The value of KΘ obtained from [η] method is higher than the value obtained from the measurements in Θ-solvent and over 100% of the value derived from the data using FOX-FLORY-SCHAEFGEN and other equivalent plots as mentioned in this paper, indicating that the unperturbed dimensions of PMMA are 30% higher in bulk than in dilute solutions.
Abstract: The value of KΘ obtained from [η] method is higher than the value of KΘ obtained from the measurements in Θ-solvent and over 100% higher than the value of KΘ obtained from the data using FOX-FLORY-SCHAEFGEN and other equivalent plots The higher value of KΘ indicates that the unperturbed dimensions of PMMA are 30% higher in bulk than in dilute solutions perhaps due to influence of the microstructure on the unperturbed dimensions of the polymeric chains
Der aus [η]R erhaltene Wert von KΘ fur PMMA ist hoher als die Werte von KΘ, die in Θ-Losungsmitteln gemessen wurden, und uber 100% hoher als der Wert von KΘ, den man nach FLORY-FOX-SCHAEFGEN und anderen entsprechenden Auftragungen ausgerechnet hat Der hohere Wert zeigt, das, vielleicht infolge des Einflusses der Mikrostruktur auf die ungestorten Dimensionen der Polymerketten, die ungestorten Dimensionen von PMMA in Substanz um 30% hoher sind als in verdunnten Losungen
TL;DR: In this article, four weakly acidic cation exchangers have been prepared by the polycondensation of cold extracted commercial cashewnutshell liquid (C-CNSL) with formaldehyde and each of the compounds gallic acid, anthranilic acid and 2-mercapto-benzothiazole.
Abstract: Four weakly acidic cation exchangers have been prepared, one by the polycondensation of cold extracted commercial cashewnutshell liquid (C-CNSL) with formaldehyde and the other three by the co-condensation of C-CNSL with formaldehyde and each of the compounds gallic acid, anthranilic acid and 2-mercapto-benzothiazole. The resins have been investigated for the selective uptake of cations from external solutions of different pH. The resin prepared by polycondensation of C-CNSL and the one prepared by its co-condensation with gallic acid showed comparatively specific absorption of Fe2+ ions.
TL;DR: From an infra-red analysis of the intermediates formed in the mercuration of sulphosalicylic acid, it has been found that the zwitterionic structure (OS · C6H2COOH · OH · Hg+) postulated for 3-mercuri-5-sulphosaliclic acid is essentially correct as discussed by the authors.
Abstract: From an infra-red analysis of the intermediates formed in the mercuration of sulphosalicylic acid, it has been found that the zwitterionic structure (OS · C6H2COOH · OH · Hg+) postulated for 3-mercuri-5-sulphosalicylic acid is essentially correct.
Aus den IR-Spektren von Zwischenprodukten der Mercurierung von Sulfosalicylsaure ergibt sich, das die fur die 3-Mercuro-5-sulfosalicylsaure postulierte zwitterionische Struktur OS · C6H2 · COOH · OH · Hg+ im Wesentlichen richtig sein durfte.