Abstract: Receptacle such as a bottle, beaker or the like made of thermoplastic material, wherein each opening for extraction is constituted by a curved or polygonal slot at least partially closed on itself and made in the end wall by partially melting the thermoplastic material of which said wall is composed, and at least the parts of the end wall surrounding said slot are hermetically fast with a covering foil or cap coated with a layer of adhesive opposite said end wall.
Abstract: A small magnet for stirring a cuvette is disclosed and the means by which the small magnet is rotated within the cuvette without any mechanical connection. Thus solutions within the cuvette may be measured and monitored, if necessary, in the total absence of daylight which reduces the impact of noise on sensors commonly used when spectrophotometric and spectroflourometric studies of solutions within the cuvette are performed.