Abstract: A cell culturing device includes a plurality of trays that are stacked on top of each other, each of the plurality of trays having a floor and an upstanding encircling sidewall, the floor and the encircling sidewall of each tray bounding a space configured to hold a liquid cell culture medium, the plurality of trays comprising a top tray, a bottom tray and one or more intermediate trays disposed therebetween. The bottom tray and the one or more intermediate trays each have a first venting port extending upwardly from the floor thereof, each first venting port bounding a channel passing through the floor of the corresponding tray and being in fluid communication with an adjacent tray. The channel of the bottom tray is openly exposed so that a gas can flow from the space of the bottom tray through the channel of the bottom tray.

Abstract: A cell culture device (10) of the cultivation of cells. The cell culture device (10) includes a plurality of trays (12a, 12b, 12c, 12d), each tray (12a, 12b, 12c, 12d) having a cell growth surface (20) and at least one wall (22, 24) extending upwardly from the cell growth surface (20). The at least one wall (22, 24) is configured to receive an additional tray thereon. A ratio of the number of the plurality of trays (12a, 12b, 12c, 12d) per a height dimension of the plurality of trays (12a, 12b, 12c, 12d) is greater than or equal to about 1 tray per 12 mm.

Abstract: A cell culture device (10) of the cultivation of cells. The cell culture device (10) includes a plurality of trays (12a, 12b, 12c, 12d), each tray (12a, 12b, 12c, 12d) having a cell growth surface (20) and at least one wall (22, 24) extending upwardly from the cell growth surface (20). The at least one wall (22, 24) is configured to receive an additional tray thereon. A ratio of the number of the plurality of trays (12a, 12b, 12c, 12d) per a height dimension of the plurality of trays (12a, 12b, 12c, 12d) is greater than or equal to about 1 tray per 12 mm.

Abstract: Process for thermal treatment of metals by passage of metallic pieces into an elongated zone under a controlled atmosphere, having an upstream section at an elevated temperature, where the controlled atmosphere comprises nitrogen and reductive chemicals, particularly hydrogen, possibly carbon monoxide; and a downstream section at a lower temperature under a controlled atmosphere. The invention is characterized by the fact that in the upstream section at an elevated temperature, the atmosphere comprises nitrogen having a residual content of oxygen between 0.5% and 5% produced by separation of air using permeation or adsorption techniques. The reductive chemicals are present at all times in a content at least sufficient to eliminate the oxygen admitted with the nitrogen.