Abstract: Provided is a low-temperature fluidity improver capable of efficiently improving the low-temperature fluidity of a biodiesel fuel. The low-temperature fluidity improver for biodiesel fuels includes a specific aromatic carboxylic acid-based compound.

Abstract: Provided is a low-temperature fluidity improver capable of efficiently improving the low-temperature fluidity of a biodiesel fuel. The low-temperature fluidity improver for biodiesel fuels includes a specific aromatic carboxylic acid-based compound.

Abstract: To provide a refrigerating unit using ammonia as a refrigerant, which uses a lubricant that is excellent in the compatibility with an ammonia refrigerant as well as in the lubricity and the stability.

Abstract: To provide a refrigerating unit using ammonia as a refrigerant, which uses a lubricant that is excellent in the compatibility with an ammonia refrigerant as well as in the lubricity and the stability.

Abstract: A lubricant for use in a refrigerator which operates with a chlorine-free Flon (fluorocarbon)-type refrigerant whose molecules do not contain chlorine. The lubricant contains a synthetic oil, and molybdenumoxysulfide diorganophosphorodithioate given by the following formula (1) and/or molybdenumoxysulfide diorganodithiocarbamate given by the following formula (2), the content of the compounds of formulae (1) and (2) in total ranges from 0.1 to 10 wt % to the content of the synthetic oil: {(RO)2PS2}2Mo2SXOY  (1) where R represents a hydrocarbon group having 3 to 20 carbon atoms, and X and Y are numbers which meet the conditions of O≦X≦4, 0≦Y≦4 and X+Y=4; and (R′2NCS2)2Mo2SX′OY′  (2) where R′ is a hydrocarbon group having 3 to 20 carbon atoms and X′ and Y′ are numbers which meet the conditions of )≦X′≦4, 0≦Y′≦4 and X′+Y′=4.

Abstract: To provide a polyalkylene glycol-based refrigerant oil for refrigerators using ammonia as a refrigerant.

Abstract: The object of the present invention is to provide a lubricant for refrigerators having good compatibility with chlorine-free Flon-type coolants, good lubricity and resistant to hygroscopicity and a composition for refrigerators using this lubricant. This lubricant contains a monomethylether of polyoxyethyleneoxypropyleneglycol where the end group at the hydrogen terminal is an oxyethylene group, represented by the following general formula (1): CH3O(AO)m(CH2CH2O)nH wherein the AO group represents oxypropylene group, or copolymeric group of oxypropylene groups and oxyethylene groups wherein the copolymeric form may be a block type and/or a random type, m is a number of 1≦m≦50, n is a number of 1≦n≦10, and the content of the oxyethylene group in the compound ranges from 5 to 60 percent by weight. A composition for refrigerators using said lubricant is also provided.

Abstract: A radio communication system is provided at an entrance gate of traffic facilities for radio communicating with a communication device carried by a vehicle. The system includes a first communication unit for transmitting first entrance data relative to the entrance gate of the traffic facilities to the communication device carried by the vehicle coming into the entrance gate, a discriminating unit for determining a vehicle type showing a kind of incoming vehicle, and a second communication unit, provided on an opposite side of the entrance gate from the first communication unit, along a direction of progress of the vehicle, for transmitting a second entrance data including data relative to the determined vehicle type to the communication device when the first communication unit transmits the first entrance data to the communication device.

Abstract: The objective of the present invention resides in providing a lubricant for refrigerators that reacts rapidly with free acids and contains a stabilizer that has good compatibility with a chlorine-free Flon-thpe coolant such as Flon 134a and the like whose molecules do not contain chlorine. The lubricant for refrigerators employing a chlorine-free Flon-type coolant in accordance with the present invention 100 parts by weight of a synthetic oil and is compounded with 0.05 to 15 parts by weight of an alicyclic epoxy compound having one or more functional groups represented by the following formula: ##STR1## (wherein R.sub.1 and R.sub.2 independently represent a hydrogen or methyl group, and may be the same or different).

Abstract: The present invention relates to a lubricated refrigerant for use in refrigerators employing hydrofluorocarbon coolants such as R 134a, R 32, R 125 and the like. The lubricated refrigerant contains fluorocarbon coolant, synthetic oil and a carbodiimide compound represented by the following general formula. R.sub.1 --N.dbd.C.dbd.N--R.sub.2, wherein R.sub.1 and R.sub.2 represent hydrogen atoms or hydrocarbly groups or nitrogen and/or oxygen containing hydrocarbly groups, and R.sub.1 and R.sub.2 may be the same or different groups. The refrigerant composition according to the present invention preferably contains said hydrofluorocarbon coolant and said lubricant at a given blending ratio.