A method for direct synthesis of cyclic carbonates is achieved by reacting at least one epoxide with carbon dioxide in the presence of a choline catalyst, such as choline chloride, under mild conditions such as a temperature between about 25 C. to 150 C. and a pressure of from about atmospheric to 75 psi (0.52 MPa), in a cyclic carbonate solvent. The choline catalyst may be the only catalyst used, and a co-catalyst or hydrogen bond donor is not necessary. The concentration of choline catalyst in the solvent ranges from about 0.5 mol % to about 10 mol %, based on the epoxide.

A fluororesin that includes a residue unit represented by formula (1), and a terminal group represented by formula (2); and a fluororesin that includes a residue unit represented by formula (1) and has a transmittance of 50% or more measured at an optical path length of 10 mm and a wavelength of 275 nm when dissolved in perfluorohexane to produce a 10 wt % perfluorohexane solution. In formula (1): Rf.sub.1, Rf.sub.2, Rf.sub.3, and Rf.sub.4 each independently represent one selected from the group consisting of fluorine atoms, C1-7 linear perfluoroalkyl groups, C3-7 branched perfluoroalkyl groups, or C3-7 cyclic perfluoroalkyl groups; the perfluoroalkyl groups may have an etheric oxygen atom; Rf.sub.1, Rf.sub.2, Rf.sub.3, and Rf.sub.4 may bond to each other to form a ring having 4 to 8 carbon atoms; and the ring may include an etheric oxygen atom. In formula (2), i is an integer of 3-20.

##STR00001##

##STR00002##

An electrolyte containing a solvent including at least one compounds of formula I, wherein A.sub.1 is an oxygen atom or a single bond, A.sub.2 is a single bond or CHR.sub.4, R.sub.1 and R.sub.2 are each independently a hydrogen atom, C1-6 alkyls or a C1-6 fluoroalkyls, R.sub.3 and R.sub.4 are each independently a hydrogen atom, a fluorine atom, C1-6 alkyls or C1-6 fluoroalkyls, A1 and A2 cannot both be single bonds simultaneously, and only one of R.sub.1 to R.sub.4 includes a fluorine atom is described. The electrolyte can make a metal negative electrode secondary battery have good cycling performance and good discharge capacity retention at low temperature.

##STR00001##

An electrolyte containing a solvent including at least one compounds of formula I, wherein A.sub.1 is an oxygen atom or a single bond, A.sub.2 is a single bond or CHR.sub.4, R.sub.1 and R.sub.2 are each independently a hydrogen atom, C1-6 alkyls or a C1-6 fluoroalkyls, R.sub.3 and R.sub.4 are each independently a hydrogen atom, a fluorine atom, C1-6 alkyls or C1-6 fluoroalkyls, A1 and A2 cannot both be single bonds simultaneously, and only one of R.sub.1 to R.sub.4 includes a fluorine atom is described. The electrolyte can make a metal negative electrode secondary battery have good cycling performance and good discharge capacity retention at low temperature.

##STR00001##

Provided is a continuous rectification apparatus for producing electronic-grade propylene carbonate, including a light component removal column and a heavy component removal column. The light component removal column is connected to a first feeding pipe. The top of the light component removal column is connected to a first condensing box. The first condensing box is connected to a first reflux tank. The first reflux tank is connected to a first conveying pump. The first conveying pump is connected to a first reflux pipe. The bottom of the light component removal column is connected to a feeding pump. The feeding pump is connected to a second feeding pipe. The second feeding pipe is connected to the heavy component removal column. The top of the heavy component removal column is connected to a second condensing box. The second condensing box is connected to one side of a second reflux tank.

Methods for total chemical synthesis of Resolvin E1 (RvE1) include Wittig reaction of two compounds having hydroxyl protecting group in the presence of a strong base, removal of the hydroxyl-protecting groups with a deprotecting reagent to produce a compound having an ester group, and hydrolysis of the ester group to obtain RvE1

Methods for total chemical synthesis of Resolvin E1 (RvE1) include Wittig reaction of two compounds having hydroxyl protecting group in the presence of a strong base, removal of the hydroxyl-protecting groups with a deprotecting reagent to produce a compound having an ester group, and hydrolysis of the ester group to obtain RvE1

A salt represented by the formula (I).

##STR00001##

wherein Z.sup.+, Q.sup.1, Q.sup.2, R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, Z, X.sup.1, X.sup.2, X.sup.a, X.sup.b, L.sup.1, L.sup.2, L.sup.3 and L.sup.4 are defined in the specification.

To provide a compound having an effect for preventing photolysis of a liquid crystal composition, and having a high solubility in the liquid crystal composition, a liquid crystal composition containing the compound, and a liquid crystal display device including the composition. The compound is represented by formula (1), the liquid crystal composition contains the compound, and the liquid crystal display device includes the composition. ##STR00001## In formula (1), R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are independently hydrogen or alkyl having 1 to 4 carbons; ring A.sup.1 and ring A.sup.2 are independently 1,4-cyclohexylene, 1,4-phenylene or the like; Z.sup.1, Z.sup.2 and Z.sup.3 are independently a single bond, alkylene or the like; and n is 0, 1 or 2.

To provide a compound having an effect for preventing photolysis of a liquid crystal composition, and having a high solubility in the liquid crystal composition, a liquid crystal composition containing the compound, and a liquid crystal display device including the composition. The compound is represented by formula (1), the liquid crystal composition contains the compound, and the liquid crystal display device includes the composition. ##STR00001## In formula (1), R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are independently hydrogen or alkyl having 1 to 4 carbons; ring A.sup.1 and ring A.sup.2 are independently 1,4-cyclohexylene, 1,4-phenylene or the like; Z.sup.1, Z.sup.2 and Z.sup.3 are independently a single bond, alkylene or the like; and n is 0, 1 or 2.