A method for liquefying a natural gas primarily including methane, preferably at least 85% of methane, the other components essentially including nitrogen and C2-C4 alkanes, in which the natural gas to be liquefied is liquefied by circulating at a pressure P0 no lower than the atmospheric pressure (Patm), P0 preferably being higher than the atmospheric pressure, in at least one cryogenic heat-exchanger (EC1, EC2, EC3) by a counter-current closed-circuit circulation in indirect contact with at least one stream of coolant gas remaining in the compressed gaseous state at a pressure P1 that is entering the cryogenic heat-exchanger at a temperature T3′ that is lower than T3, T3 being the liquefaction temperature of the liquefied natural gas at the pressure P0 at the output of said cryogenic exchanger, characterized in that the coolant gas includes a mixture of nitrogen and at least one other component selected from among neon and hydrogen.

Provided is a supercritical fluid chromatography system, and components comprising such a system, including one or more of a supercritical fluid chiller, a supercritical fluid pressure-equalizing vessel, and a supercritical fluid cyclonic separator. The supercritical fluid chiller and the use of the chiller allow efficient and consistent pumping of liquid-phase gases employing off-the-shelf HPLC pumps in the supercritical chromatography system using liquid-phase gas mobile phase. The pressure equalizing vessel allows the use of off the shelf HPLC column cartridges in the supercritical chromatography system. The cyclonic separator efficiently and effectively allows for separation of sample molecules from a liquid phase or gas phase stream of a supercritical fluid.

Compositions, systems and methods for introducing lubricants, and additives, that are designed to work with environmentally friendly refrigerants into vehicle heat management systems including passenger compartment air conditioning (A/C) systems are disclosed. Methods for charging lubricants and specific additives using environmentally desirable (low GWP) refrigerant or refrigerant blend compositions into an environmentally friendly system, such as a system that uses HFO-1234yf, are also disclosed.

A bipolar plate having side ports is described for use with an electrochemical cell. A side port having a high aspect ratio will have an effect on the partial pressure of the reactant gasses and prevent high pressure drop of the working fluid transport to the electrodes. The membrane electrode assembly may have a high aspect ratio and the port opening may be on the long side of the bipolar plate. The electrochemical cell may be configured in an enclosure that is maintained at less than atmospheric pressure which further increases the need for low pressure drop fuel deliver to the electrodes, especially in electrochemical compressor applications.

The present invention provides a working fluid composition for a refrigerating machine, comprising: a refrigerating machine oil comprising, as a base oil, a mixed ester of (A) a complex ester obtainable by synthesis of at least one polyhydric alcohol selected from neopentyl glycol, trimethylolpropane and pentaerythritol, a C6-C12 polybasic acid, and a C4-C18 monohydric alcohol or a C4-C18 monocarboxylic fatty acid, and (B) a polyol ester obtainable by synthesis of at least one polyhydric alcohol selected from neopentyl glycol, trimethylolpropane, pentaerythritol and dipentaerythritol, and a C4-C18 monocarboxylic fatty acid, in a mass ratio of (A) the complex ester/(B) the polyol ester of 5/95 to 95/5; and a hydrocarbon refrigerant having 3 or 4 carbon atoms, wherein a refrigerant dissolved viscosity, at a temperature of 80° C. and an absolute pressure of 1.5 MPa, is 1.0 mm.sup.2/s or more.

Provided is a chiller and system that may be utilized in a supercritical fluid chromatography method, wherein a non-polar solvent may replace a portion or all of a polar solvent for the purpose of separating or extracting desired sample molecules from a combined sample/solvent stream. The system may reduce the amount of polar solvent necessary for chromatographic separation and/or extraction of desired samples. The system may incorporate a supercritical fluid chiller, a supercritical fluid pressure-equalizing vessel and a supercritical fluid cyclonic separator. The supercritical fluid chiller allows for efficient and consistent pumping of liquid-phase gases employing off-the-shelf HPLC pumps. The pressure equalizing vessel allows the use of off-the-shelf HPLC column cartridges. The system may further incorporate the use of one or more disposable cartridges containing silica gel or other suitable medium. The system may also utilize an open loop cooling circuit using fluids with a positive Joule-Thomson coefficient.

A method for operating a refrigerant circulation system comprising a compressor, a condenser, an expansion mechanism, and an evaporator connected in this order with piping, wherein a refrigerant comprising trifluoroiodomethane is used as a refrigerant; a refrigerating machine oil comprising, as a base oil, a polyolester synthesized from a polyhydric alcohol and fatty acids, with a proportion of a fatty acid having 9 carbon atoms in the fatty acids being 65 mol % or less is used as a refrigerating machine oil; and a temperature of an entire area of the refrigerant circulation system is kept at 160° C. or lower.

Compositions, systems and methods for introducing lubricants, and additives, that are designed to work with environmentally friendly refrigerants into vehicle heat management systems including passenger compartment air conditioning (A/C) systems are disclosed. Methods for charging lubricants and specific additives using environmentally desirable (low GWP) refrigerant or refrigerant blend compositions into an environmentally friendly system, such as a system that uses HFO-1234yf, are also disclosed.

A refrigerant and oil treatment composition for introduction into a vapor-compression system such as a refrigerator, heat pump, freezer, air conditioner, thermal control device, and refrigerant recovery apparatus has a composition alcohol and a drying agent. The drying agent is 2,2-dimethoxypropane which can react with moisture in the system to form an alcohol as a reaction product. The alcohol reaction product along with the composition alcohol separates any acid in the system from oil, refrigerant and hard surfaces of the system to form an acid-containing solvent composition. The quantity of the composition introduced into the system is based on the adsorption capacity of the filter-drier.

A water-based refrigerant for a thermal working machine. The refrigerant for a thermal working machine (150) having an evaporator (A), a condenser (B), a compressor (C.sub.GL), and a throttle element (D). The refrigerant is based on water and comprises a refrigerant component with a hydroxyl group, for example in the form of ethanol. The use of such a mixture as a refrigerant for a thermal working machine and for a thermal working machine having such a refrigerant, and to a method for operating a thermal working machine having such a refrigerant is also disclosed.