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991.
The micellar polymerisation of ionic surfactants such as allyldodecyl-dimethylammonium bromide and 3-dodecyl-1-vinyl imidazolium iodide has been studied by conductimetry in aqueous solution. The polymerisation was carried out using two different sources of γ rays directed into solutions of surfactant above the critical micellar concentration. Conductimetry is shown to be a very good physicochemical method for analysis of these solutions. The results showed different behaviour for the two surfactants, which has highlighted a change in the structure of their aggregates which led to the assumption of an interaction between the polymers of high mass and different products of the polymerisation (oligomers, products of degradation, monomers etc.). Ultrafiltration experiments coupled with 1H-NMR and conductivity analysis confirm these assumptions. 相似文献
992.
J. Parnell 《Journal of Petroleum Geology》1992,15(1):51-70
Thick Permo-Triassic sandstones occur in two basins in Northern Ireland. The sandstones are fluvio-deltaic, including an oolitic facies, and are interbedded with mudrocks. They exhibit petrographic features which are typical of red beds and are widely found in the Permo-Triassic elsewhere in the British Isles. The predominant cements are haematite, potassium feldspar. illite and carbonates. Gypsum, anhydrite and dolomite cements occur in the regions of deepest burial. which represent the basin centres. There was widespread leaching of carbonate/sulphate cements, but calcite is preserved in the oolitic facies and below the sub-Cretaceous (chalk) unconformity. The dissolution of cements and framework grains was due to leaching by meteoric fluids. Precipitation of kaolinite in secondary pores, and subsequent illitization, represent fluctuations in the meteoric hydraulic head. Deep boreholes exhibit sandstone porosities which indicate that there may be significant reservoir potential where adequate seals and traps are present. 相似文献
993.
J. Hospers 《Journal of Petroleum Geology》1992,15(2):359-361
Koyi (1991) has described physical modelling experiments on the initiation of salt diapirism. He also compares his results with the results of an investigation of salt tectonics in the northern part of the Norwegian-Danish Basin by Hospers et al. (1988).
Koyi's comments on this investigation are not altogether favourable. Below, I intend to show that Koyi's criticisms are not valid, as they stem from a combination of: (1) built-in features present in his models which limit their applicability; and (2) an incomplete understanding of the structural setting in which salt diapirism was initiated in the northern part of the Norwegian-Danish Basin. 相似文献
Koyi's comments on this investigation are not altogether favourable. Below, I intend to show that Koyi's criticisms are not valid, as they stem from a combination of: (1) built-in features present in his models which limit their applicability; and (2) an incomplete understanding of the structural setting in which salt diapirism was initiated in the northern part of the Norwegian-Danish Basin. 相似文献
994.
995.
R. M. Khalimulin 《Chemical and Petroleum Engineering》1992,28(5):337-338
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 5, p. 36, May, 1992. 相似文献
996.
997.
A. M. Vasil'ev 《Chemical and Petroleum Engineering》1992,28(7):409-410
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 7, pp. 1–2, July, 1992. 相似文献
998.
999.
1000.