Abstract: A critical point drying apparatus for sample preparation in electron microscopy and semiconductor wafer production includes a computer system to automate the operational modes in drying the specimen. These operational modes controlled by the computer system are: cooling, in which a drying chamber is cooled; starting, in which the specimen chamber is filled with a transitional fluid; purging, in which the transitional fluid purges an intermediary fluid from the drying chamber and the purged intermediary fluid is collected by a collector condenser; heating, in which the drying chamber is heated to elevate the transitional fluid to its critical point temperature and pressure; and bleeding, in which the drying chamber is depressurized to atmospheric pressure at a very slow rate until the drying chamber is completely vented, which signals the end of the drying operation. The computer system interfaces with a remote client terminal to update the status of the operation of the critical point drying apparatus.

Abstract: A brine cooling apparatus is provided which addresses an environmental problem by not contributing to global warming and can prevent brine from freezing within a heat exchanger. The apparatus is structured such that a screw compressor, a condenser, a main expansion valve and an evaporator are connected by a pipe so as to cool brine flowing through the evaporator. The refrigerant is an ammonia refrigerant, the evaporator is a plate type heat exchanger constructed by laying a plural sheets of plates, and capacity control means is provided in such a manner as to control a capacity of the screw compressor in accordance with the flow amount of the brine.

Abstract: An air curtain generator generates an air curtain in a refrigerant compartment of a refrigerator. In the air curtain generator, a sensor senses open and closed states of a refrigerant compartment door. A brushless direct current air curtain fan blows cool air into a refrigerant compartment according to a sensing result of the sensor in order to generate an air curtain in the refrigerant compartment. A direct current power source supplies a direct current driving current to the brushless direct current air curtain fan. A driver drives the brushless direct current air curtain fan. A microcomputer controls an operation of the driver according to the sensing result of the sensor. The air curtain generator maximizes functions of an air curtain generator by applying a brushless direct current air curtain fan having low noise level, low power consumption, and high efficiency thereto.