Chiral diacetylenes featuring ester and urethane groups are readily prepared from amino acids and diynediols. The ability of the butadiyne moiety to undergo topotactic polymerization is dependent on both the length of the chain to the urethane group and the size of the amino acid. In some cases, the polymerization proceeds as well as the well-studied achiral parent compound, 4BCMU. The polymers form yellow solutions in good solvents where the chains adopt a random-coil configuration. Addition of a nonsolvent changes the solution color to red as the chains adopt a helical conformation.

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Thermally-reduced oil formation volume factor is correlated with solution gas-oil ratio from 0 to 3,500 cu ft/bbl. This correlation was made from the differential liberation curves of 159 analyses of saturated Eastern Venezuelan crudes. Average error, determined by comparing correlation and calculated with the laboratory-determined oil formation volume factor, was found to be 2.00 per cent. Average error of 104 separator flash tests was 1.97 per cent. Introduction Based on the original method of Katz, a correlation of thermally-reduced oil formation volume factor and solution gas-oil ratio has been made from saturated Eastern Venezuelan crudes. The accuracy of this correlation, which requires a minimum amount of data and is easy to use, is sufficient for most reserves estimates. The average correlation error of 2.00 per cent for reservoir differential data compares closely with the 1.97 per cent error for separator flash data. While the accuracy of this correlation for other oil-producing areas is not known, there is close agreement with the general correlation of Katz. Also, there is a wide crude-oil gravity range represented, 15 degrees to 47.5 degrees API, with reservoir temperatures that range from 142 degrees to 307 degrees F. It is thought, therefore, that this correlation can be universally applied with reasonable accuracy. Wherever sufficient data exist, a cross plot can quite easily be made so that an area-oriented correlation is obtained. Construction and Error Fig. 1 is a correlation obtained from 159 differential liberation curves of saturated Eastern Venezuelan crudes. This correlation closely parallels the Katz general correlation previously made to a maximum solution ratio of 1,300 cu ft/bbl. Data obtained from volatile Venezuelan crudes shows that this correlation can be extended to 3,500 cu ft/bbl with good data conformance. The extension of the correlation is almost linear. Data used in Fig. 1 represent crude oils which range from 15 degrees to 47.5 degrees API. Reservoir temperatures of these crudes range from 142 degrees to 307 degrees F.

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TX 75083-3836, U.S. A., fax 01-972-952-9435. AbstractThe Wushenqi gas field is a low permeability gas play under development by the Changqing Oilfield Company of PetroChina (PCOC). The first well in this field was drilled and hydraulically fractured in 1994. Out of the ten wells initially drilled, nine were hydraulically fractured using a design based on historical knowledge and area best practices. The average gas production of the 10 wells was 586000 scf/day (16,600 m3/day), which was less than the production required for economical development of the field.3. An improved well design reflecting data acquisition, fracturing process, and production requirements. 4. A modified fracturing treatment d esign tailored for the expected Kh and deliverabilty requirements of the various zones. 5. An on-site test program using pre-fracture treatment injection testing to verify the permeability.