Abstract: The present disclosure relates to a method of preparing an organic zinc catalyst through solid phase blending that does not require a solvent and a washing process, and a method of preparing a polyalkylene carbonate resin by using the organic zinc catalyst prepared thereby.

Abstract: A display device is provided. The display device includes a substrate including a display area and a pad area, which is disposed on one side of the display area, a plurality of conductive layers disposed on the substrate, in the display area and the pad area, a passivation layer disposed on the conductive layers, and a plurality of light-emitting elements disposed on the passivation layer, in the display area, and spaced apart from one another, wherein at least one of the conductive layers includes a first metal layer, a second metal layer, which is disposed on the first metal layer, and a third metal layer, which is disposed on the second metal layer, the first metal layer includes vanadium (V), the second metal layer includes aluminum (Al) or an Al alloy, and the third metal layer includes V or titanium (Ti).

Abstract: An air conditioning system includes a phase separator separating a gaseous refrigerant and a liquid refrigerant from a flowing refrigerant, an evaporator evaporating the liquid refrigerant separated by the phase separator, and at least one compressor including a first compressing part receiving the refrigerant via the evaporator and a second compressing part receiving both of the gaseous refrigerant separated by the phase separator and the refrigerant via the first compressing part.

Abstract: It is possible to prevent that a liquid refrigerant is included in a refrigerant injected into a compressor. Accordingly, the risk of liquid compression of the compressor is greatly reduced, thereby decreasing the possibility of damage to the compressor and improving reliability and performance.

Abstract: A heat pump type cooling/heating apparatus comprises a coolant injection path and a gaseous coolant adjustment valve. The coolant injection path may be split between a cascade heat exchanger and an evaporator of a low-temperature refrigeration cycle to inject coolant into a low pressure side compressor, or between a water coolant heat exchanger and cascade heat exchanger to inject coolant into a high pressure side compressor of a high temperature refrigeration cycle.

Abstract: The present invention relates to a controlling method of an air conditioner. The controlling method of an air conditioner having a phase separator, an expansion valve, a control valve, an evaporator, a multistage compressor, and a condenser, includes the steps of sensing an order to operate the air conditioner, stabilizing the air conditioner, setting a degree of superheat of refrigerant in the air conditioner, and setting an optimum intermediate pressure of the refrigerant of the air conditioner.

Abstract: The present invention discloses an air conditioning system comprises a phase separator separating a gaseous refrigerant and a liquid refrigerant from a flowing refrigerant, an evaporator evaporating the liquid refrigerant separated by the phase separator, and at least one compressor including a first compressing part receiving the refrigerant via the evaporator and a second compressing part receiving both of the gaseous refrigerant separated by the phase separator and the refrigerant via the first compressing part, wherein a volume of a first cylinder of the first compressing part is different from a volume of a second cylinder of the second compressing part.

Abstract: It is possible to prevent that a liquid refrigerant is included in a refrigerant injected into a compressor. Accordingly, the risk of liquid compression of the compressor is greatly reduced, thereby decreasing the possibility of damage to the compressor and improving reliability and performance.