Abstract: A CO2 refrigeration system (1) includes: a compressor (3), a gas cooler (5), a temperature sensor (17) and an electronic control system (13), the electronic control system including a processor device (15) arranged to control operation of the compressor (3) according to input signals received from the temperature sensor (17), wherein the temperature sensor (17) is positioned to read an output temperature of the gas cooler. A method for controlling a compressor (3) in a CO2 refrigeration system (1) is also disclosed.

Abstract: Disclosed is a sensor shield for use in a multi-shelf merchandise display unit including a plurality of sensors mounted on a wall of the unit and opposite a source of illumination, in which each sensor corresponds to a single shelf and in which the shelves are at least semi-porous to the illumination. The shield comprises i) a plate having a length that is sufficient substantially to reduce or prevent incident illumination from the shelf above reaching the sensor; and ii) means to attach the plate to casing of or around the sensor or the wall of the unit. The plate is opaque to the illumination detected by the sensor. Also disclosed is a method to reduce the interference of light in a multi-shelf merchandise display unit from shelves above a shelf on which stock levels are being measured and a method for monitoring stock levels in a retail display cabinet by measuring light entering the retail display cabinet.

Abstract: A nozzle for spraying apparatus to distribute crop treatment liquid. The nozzle is of general ogee shape with a base and an upper wall spaced from the base and connected to it by side walls. The upper wall extends from the apex of the base partially along the base to terminate in a trailing edge. The nozzle is placed in a high velocity air stream and liquid introduced between the base and upper wall. The high velocity airstream atomizes the liquid and distributes it in the surrounding environment. The nozzle is particularly useful in electrostatic spraying apparatus and may be made of plastics material to inhibit induction of electrostatic charge on the nozzle.