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Abstract  

The heat capacities of binary aqueous solutions of 1,2-ethanediol, 1,2-propanediol and 1,2-butanediol were measured at temperatures ranging from 283.15 to 338.15 K by differential scanning calorimetry. The partial molar heat capacities at the infinite dilution were then calculated for the respective alkanediols. For 1,2-ethanediol or 1,2-propanediol, the partial molar heat capacities at the infinite dilution of increased with increasing temperature. In contrast, the partial molar heat capacities of 1,2-butanediol at the infinite dilution decreased with increasing temperature. Heat capacity changes by dissolution of the alkanediols were also determined. Heat capacity changes caused by the dissolution of 1,2-ethanediol or 1,2-propanediol were increase with increasing temperature. On the other hand, heat capacity changes caused by the dissolution of 1,2-butanediol are decrease with increasing temperature. Thus our results indicated that the structural changes of water caused by the dissolution of 1,2-butanediol differed from that of the two other alkanediols.

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der Ferkelaufzucht und in der Broilermast. Agribiol. Res. 49 , 1. Zum Effect von Phytase auf die Scheinbare Verdaulichkeit und Gesamtverwertung von Eisen, Kupfer, Zink und Mangan bei abgestufter CaVersorgung in der

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The investigations concerning the thermal behaviour of a series of Ni(II) and Cu(II) complexes of type [MLCln]· mH2O ((1) M:Ni, L:L(1), n=1, m=2; (2) M:Cu, L:L(2), n=1, m=2; (3) M:Ni, L:L(3), n=2, m=0; (4) M:Cu, L:L(3), n=1, m=2) are presented in this paper. The ligands L(1)-L(3) have been synthesised by template condensation of 1,2-diaminoethane with formaldehyde and 2-amino-1,3,4-thiadiazole-5-thiole or 2-acetamino-1,3,4-thiadiazole-5-sulfonamide. The bonding and stereochemistry of the complexes have been characterised by IR, electronic and magnetic studies at room temperature. The thermal behaviour provided confirmation of the complex composition as well as the number and the nature of water molecules and the intervals of thermal stability. The different nature of the ligands and/or the metallic ions generates a different thermal behaviour for complexes. The complexes do not show biological activity against HIV virus.

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Abstract  

Parent and mixed ligand complexes of manganese(II) ion were prepared with water, sulfate ion and 1,2-ethanediol as ligands. The IR spectra and the thermoanalytical curves of the complexes were recorded. Oxygen atoms bound by one or two coordinate bonds to the metal ion, or by hydrogen-bonds in the crystal, were observed. As for the water molecule, ‘crystal’ and ‘monohydrate’ type of 1,2-ethanediol molecules were found, depending on the type of binding of the oxygen atoms.

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Rare earth elements 1,3,5-benzenetricarboxylates were prepared as solids of the general formula Ln(C9H3O6nH2O, where n=6 for La-Dy and n=4 for Ho-Lu,Y. Their solubilities in water at 293 K are of the order 10-4-10-6 mol dm-3. The IR spectra of the complexes indicate that the carboxylate groups are bridging and bidentate chelates. Hydrated 1,3,5-benzenetricarboxylates lose water molecules during heating in one step (La-Tb), two steps (Y, Ho-Tm) or three steps (Dy, Yb, Lu). The anhydrous complexes are stable up to 573-742 K and decompose to oxides (Ce-Lu) at higher temperatures.

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Abstract  

1,3-propanediaminotetramethylenephosphonic acid (PDTMP, H8L) was prepared and its complexes with some lanthanide ions (La(III), Eu(III), Gd(III) and Sm(III)) were isolated. The IR spectra and thermal stabilities of PDTMP and its complexes were studied. All the complexes contain physically and coordinately bound water molecules, which are released from the solid samples below 370C. On heating PDTMP decomposes to phosphorus oxides, while its anhydrous complexes decompose to lanthanide oxides, and cyclic and linear polyphosphates between 400 and 1000C.

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Summary  

Mixed ligand nickel(II) complexes of different compositions were prepared with water, sulfate ion and 1,2-ethanediol as ligands. The magnetic susceptibility data, the IR spectra and the thermoanalytical curves of the complexes were recorded. Oxygen atoms bound by one or two coordinate bonds to the metal ion, or by hydrogen-bonds in the crystal state were observed. All complexes are sensitive for moisture. The bis complex proved to be the more stable complex.

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Abstract  

Composition and structure of crystals of unknown origin, crystallizing spontaneously from ethylenediamine on standing, has been determined by elemental analysis, FTIR, 1H and 13C NMR spectroscopy and X-ray diffraction. The crystal with molecular formula C6H14N4 has been found to be a highly symmetric saturated imino compound with double-ring structure, and unambiguously identified as trans-1,4,5,8-tetraazodecalin by 1H NMR and powder X-ray diffraction based on both its specific AA'BB' spin coupling system and simulated XRD pattern calculated from available data of previous single crystal structure determination, respectively. Simultaneous TG/DTA measurement shows one-step degradation of this compound. The volatile decomposition products have been followed by both TG/DTA-MS and TG-FTIR. Group of the largest fragments (m/z=80, 81 and 82) observed by TG/DTA-MS corresponds to an aromatic 1,4-diazine (pyrazine). In the EGA-FTIR spectrum of released gaseous species measured at the highest evolution rate by TG-FTIR, ethylenediamine can be identified as another decomposition product.

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Kim, Y. J. and Hwang, D. K. (1997): Isolation of basic 34 kDa beta-1,3-glucanase with inhibitory activity against Phytophthora capsici from hehher stems. Physiological and Molecular Plant Pathology 50, 103-115. Isolation of

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70 Debelder, A. N., Bourne, E. J. & Weigel, W. (1966): Studies on tert -butyl derivatives of D-glucose. Carbohydr. Res. , 3 , 1-6. Studies on tert -butyl

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