Abstract: A method of evaporating liquid from a liquid and solid solution in a container within a chamber involves moving the container in an orbital motion such that the solution forms a vortex configuration within the container and also involves directing gas into the container. The gas is directed into the container from a point source above the liquid in the container to decrease the partial pressure on the solution thereby increasing the evaporation rate of the liquid from the solution. To further increase evaporation of the liquid, heat may be applied to the container. The temperature within the chamber may be regulated by sensing the temperature within the chamber and controlling the application of heat to the container in response to the temperature sensed within the chamber.

Abstract: A vortex evaporator having a holder for holding at least one container presents a chamber wherein liquid is evaporated from a liquid and solid solution in a container. The vortex evaporator also includes a drive mechanism, coupled to the holder, for moving each container in an orbital motion within the chamber to cause the solution in the container to form a vortex configuration. The vortex evaporator further includes a gas supply system for directing gas into the container to increase the evaporation rate of the liquid and a control system for controlling operation of the vortex evaporator. In an alternative embodiment, a vacuum supply system may be utilized instead of the gas supply system. Further, the vortex evaporator will preferably include a heater, at least one liquid level sensor, a heat sensor and a motion dampening assembly all located within the chamber.

Abstract: A microprocessor-controlled power supply with substantially independent high voltage outputs monitors and regulates two separate electrophoresis applications running simultaneously. The software associated with the dual output power supply provides independent control of each application, including automatic crossover between control parameters within each application. After parameter values are selected for each application and the applications are initiated, the software monitors the actual parameter values with relation to the selected values and adjusts the actual value of the controlling parameter for each initiated application to maintain the actual parameter values within the selected parameter values.

Abstract: A method and apparatus for controlling ventilation of a laboratory fume hood. The face velocity of air entering the fume hood is sensed by a velocity sensor, and a stepping motor controls damper blades in the exhaust duct to normally maintain the face velocity at a nearly constant level. A potentiometer senses the position of a sash that controls the fume hood face opening. When the sash is 40% open or less, the damper blades are adjusted to keep the volume rate of flow through the fume hood nearly constant. An alarm signal is generated if the flow is unduly low. The damper blades are fully opened either if a switch is operated or if the sash is abruptly opened. An unoccupied mode permits reduced air flow when the sash is nearly closed and the laboratory is unoccupied.

Abstract: An improved method and apparatus for testing coins, metallic credit tokens and similar objects, capable of determining both type or denomination and genuineness thereof, utilize the effect upon the electrical impedance of a sensing component from the presence of an object under test in physical proximity to such component and the effect upon the direct current time constant of an electrical circuit containing such component from the influence of presence of such object upon the effective electrical impedance of such component, and employ a novel testing technique primarily involving determining whether or not a direct current voltage output from such circuit has risen to within a predetermined range of voltage level thereof in time coincidence with an interval of test enablement occurring a predetermined period of time, characteristic of acceptable objects of the particular kind being tested for, after an initial direct current energization of such circuit.