This invention relates to an anionic-cationic-nonionic surfactant as substantially represented by the formula (I), production and use thereof in tertiary oil recovery. The anionic-cationic-nonionic surfactant of this invention exhibits significantly improved interfacial activity and stability as compared with the prior art. With the present anionic-cationic-nonionic surfactant, a flooding fluid composition for tertiary oil recovery with improved oil displacement efficiency and oil washing capability as compared with the prior art could be produced.

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In the formula (I), each group is as defined in the specification.

Processes for the preparation of 2,5-dihydroxybenzenesulfonic acid salts of formula (I) and a crystalline form of potassium 2,5 2,5-dihydroxybenzenesulfonic acid are provided. ##STR00001##

Processes for the preparation of 2,5-dihydroxybenzenesulfonic acid salts of formula (I) and a crystalline form of potassium 2,5 2,5-dihydroxybenzenesulfonic acid are provided. ##STR00001##

A resist composition including a compound represented by formula (b1) in which R.sup.b1 represents an aryl group which may have a substituent; R.sup.b2 and R.sup.b3 each independently represents an aryl group which may have a substituent or an alkyl group which may have a substituent; provided that at least one of the aryl group represented by R.sup.b1 and the aryl group or the alkyl group represented by R.sup.b2 or R.sup.b3 has a substituent containing a halogen atom, and at least one of the aryl group represented by R.sup.b1 and the aryl group or the alkyl group represented by R.sup.b2 or R.sup.b3 has a substituent containing a sulfonyl group; and X.sup.− represents a counteranion ##STR00001##

A resist composition including a compound represented by formula (b1) in which R.sup.b1 represents an aryl group which may have a substituent; R.sup.b2 and R.sup.b3 each independently represents an aryl group which may have a substituent or an alkyl group which may have a substituent; provided that at least one of the aryl group represented by R.sup.b1 and the aryl group or the alkyl group represented by R.sup.b2 or R.sup.b3 has a substituent containing a halogen atom, and at least one of the aryl group represented by R.sup.b1 and the aryl group or the alkyl group represented by R.sup.b2 or R.sup.b3 has a substituent containing a sulfonyl group; and X.sup.− represents a counteranion ##STR00001##

The filter medium is a filter medium which uses a liquid containing oil and water as a separation target, and has a channel for the liquid. The filter medium includes a base constituting the channel, and one or more of nitrogen-containing fluorine compounds which are provided on at least a portion of a surface of the channel. The nitrogen-containing fluorine compound includes an oil-repellency imparting group and any one hydrophilicity imparting group selected from a group consisting of an anion type, a cation type, and an amphoteric type, in a molecule.

The present disclosure relates to the methods for the preparation of reactive [F-18]fluoride in a form of [F-18]sulfonyl fluoride suitable for efficient radiolabeling without an azeotropic evaporation step by the use of anion exchange resin and sulfonyl chloride, and its applications in the manufacturing of PET radiopharmaceuticals.

The present disclosure relates to the methods for the preparation of reactive [F-18]fluoride in a form of [F-18]sulfonyl fluoride suitable for efficient radiolabeling without an azeotropic evaporation step by the use of anion exchange resin and sulfonyl chloride, and its applications in the manufacturing of PET radiopharmaceuticals.

The present disclosure relates to the methods for the preparation of reactive [F-18]fluoride in a form of [F-18]sulfonyl fluoride suitable for efficient radiolabeling without an azeotropic evaporation step by the use of anion exchange resin and sulfonyl chloride, and its applications in the manufacturing of PET radiopharmaceuticals.

There is disclosed a process for producing taurine from ammonium isethionate by the ammonolysis of alkali isethionate in the presence of alkali ditaurinate or alkali tritaurinate, or their mixture, to inhibit the formation of byproducts and to continuously convert the byproducts of the ammonolysis reaction to alkali taurinate. Alkali taurinate is reacted with ammonium isethionate to obtain taurine and to regenerate alkali isethionate. The production yield is increased to from 90% to nearly quantitative. The ammonolysis reaction is catalyzed by alkali salts of hydroxide, sulfate, sulfite, phosphate, or carbonate.