Disclosed is a method for linkage recovery of an organic acid in an aqueous organic acid solution. The method comprises: mixing a solution with an organic acid concentration lower than 20 wt % with a specific extractant and then subjecting same to counter-current extraction so as to obtain an extract phase and a raffinate phase; and subjecting the extract phase together with a solution with an acid concentration higher than 70 wt % to an azeotropic rectification so as to recover an organic acid. When the concentration of the aqueous organic acid solution is 20 wt %-70 wt %, the aqueous organic acid solution is extracted and concentrated to make the concentration of the aqueous organic acid solution higher than 70 wt %.

The present invention is concerned with a nonaqueous electrolytic solution having an electrolyte salt dissolved in a nonaqueous solvent, the nonaqueous electrolytic solution containing a compound represented by the following general formula (X), in which a polar group (X) is bound to a phosphorus atom (P), and capable of improving electrochemical characteristics in a broad temperature range; an energy storage device using the same; and a novel compound.

##STR00001##

In the formula, R.sup.10 and R.sup.20 are each independently an organic group selected from the group consisting of an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 3 to 6 carbon atoms, and an aryl group having 6 to 12 carbon atoms, or a lithium atom; and X is a polar group (i) containing a —C(═O) group, a —P(═O) group, or an —S(═O).sub.2 group, a polar group (ii) containing a —CN group or an alkyl group having 1 to 6 carbon atoms, in which a part of hydrogen atoms is substituted with a fluorine atom, or a 4- to 7-membered ring polar group (iii) containing a —C(═O)—O— group or a —C(═O)—N— group, provided that when X is a 4- to 7-membered ring polar group (iii) containing a —C(═O)—N— group, at least one of R.sup.10 and R.sup.20 is a lithium atom.

The present invention is concerned with a nonaqueous electrolytic solution having an electrolyte salt dissolved in a nonaqueous solvent, the nonaqueous electrolytic solution containing a compound represented by the following general formula (X), in which a polar group (X) is bound to a phosphorus atom (P), and capable of improving electrochemical characteristics in a broad temperature range; an energy storage device using the same; and a novel compound.

##STR00001##

In the formula, R.sup.10 and R.sup.20 are each independently an organic group selected from the group consisting of an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 3 to 6 carbon atoms, and an aryl group having 6 to 12 carbon atoms, or a lithium atom; and X is a polar group (i) containing a —C(═O) group, a —P(═O) group, or an —S(═O).sub.2 group, a polar group (ii) containing a —CN group or an alkyl group having 1 to 6 carbon atoms, in which a part of hydrogen atoms is substituted with a fluorine atom, or a 4- to 7-membered ring polar group (iii) containing a —C(═O)—O— group or a —C(═O)—N— group, provided that when X is a 4- to 7-membered ring polar group (iii) containing a —C(═O)—N— group, at least one of R.sup.10 and R.sup.20 is a lithium atom.

Provided are a near infrared ray absorbent composition which can form a cured film having excellent near infrared ray shielding properties, a near infrared ray cut filter, a manufacturing method of a near infrared ray cut filter, a solid image pickup element, and a camera module. The near infrared ray absorbent composition includes a copper complex that is other than a copper phthalocyanine complex and has a maximum absorption wavelength in a wavelength range of 700 to 1,200 nm and in which a molar light absorption coefficient at the maximum absorption wavelength is greater than or equal to 100 (L/mol.Math.cm).

Provided are a near infrared ray absorbent composition which can form a cured film having excellent near infrared ray shielding properties, a near infrared ray cut filter, a manufacturing method of a near infrared ray cut filter, a solid image pickup element, and a camera module. The near infrared ray absorbent composition includes a copper complex that is other than a copper phthalocyanine complex and has a maximum absorption wavelength in a wavelength range of 700 to 1,200 nm and in which a molar light absorption coefficient at the maximum absorption wavelength is greater than or equal to 100 (L/mol.Math.cm).

The present invention relates to an enzymatic synthesis of 4′-ethynyl-2′-deoxy nucleosides and analogs thereof, for example EFdA, that eliminates the use of protecting groups on the intermediates, improves the stereoselectivity of glycosylation and reduces the number of process steps needed to make said compounds. It also relates to the novel intermediates employed in the process.

The present invention relates to an enzymatic synthesis of 4′-ethynyl-2′-deoxy nucleosides and analogs thereof, for example EFdA, that eliminates the use of protecting groups on the intermediates, improves the stereoselectivity of glycosylation and reduces the number of process steps needed to make said compounds. It also relates to the novel intermediates employed in the process.

The use of surfactant formulations comprising long-chain alcohols as additives in aqueous polymer dispersions for production of porous polymer coatings, preferably for production of porous polyurethane coatings, is described.

A non-aqueous electrolyte for a lithium-ion battery and a lithium-ion battery. The non-aqueous electrolyte comprises unsaturated phosphate compounds and unsaturated cyclic carboxylic acid anhydride compounds. The unsaturated phosphate compounds have the structure illustrated in structural formula 4; structural formula 4: R.sub.13, R.sub.11, and R.sub.12 are independently selected from hydrocarbon groups having 1-5 carbon atoms respectively, and at least one of R.sub.13, R.sub.11, and R.sub.12 is an unsaturated hydrocarbon group containing double bonds or triple bonds; the unsaturated cyclic carboxylic acid anhydride compounds have the structure illustrated in structural formula 5; structural formula 5: R.sub.14 is independently selected from vinylidene having 2-4 carbon atoms or fluoro-substituted vinylidene. By means of the synergistic effect of two compounds, the non-aqueous electrolyte has excellent high-temperature cycling performance and storage performance, and also has lower impedance and good low-temperature performance. ##STR00001##

A non-aqueous electrolyte for a lithium-ion battery and a lithium-ion battery. The non-aqueous electrolyte comprises unsaturated phosphate compounds and unsaturated cyclic carboxylic acid anhydride compounds. The unsaturated phosphate compounds have the structure illustrated in structural formula 4; structural formula 4: R.sub.13, R.sub.11, and R.sub.12 are independently selected from hydrocarbon groups having 1-5 carbon atoms respectively, and at least one of R.sub.13, R.sub.11, and R.sub.12 is an unsaturated hydrocarbon group containing double bonds or triple bonds; the unsaturated cyclic carboxylic acid anhydride compounds have the structure illustrated in structural formula 5; structural formula 5: R.sub.14 is independently selected from vinylidene having 2-4 carbon atoms or fluoro-substituted vinylidene. By means of the synergistic effect of two compounds, the non-aqueous electrolyte has excellent high-temperature cycling performance and storage performance, and also has lower impedance and good low-temperature performance. ##STR00001##