Abstract:
The invention relates to a solar energy absorber unit for use in a solar energy absorbing device, and methods of producing the same. The unit includes a collector plate made of a heat- conductive material having a front surface adapted to absorb solar energy and to convert the solar energy to heat, and a rear surface opposite to the front surface. A rear panel has an inner surface and an outer surface, the inner surface being attached to areas of the rear surface of the collector plate via a fluid-tight bond, whereby the inner surface of the panel and the rear surface of the collector plate together define a fluid-conveying channel between the areas of the rear surface of the plate where the panel is attached. The unit has connectors for introducing a heat extraction fluid into the channel and for removing the fluid therefrom. The collector plate and preferably the rear panel are each made of a core layer of an aluminum alloy provided with a cladding layer formed on a side of the core layer that confronts the fluid-conveying channel, the cladding layer being made of aluminum or an aluminum alloy having a total content of alloying elements and impurities, if any, of no more than 0.5 wt.%.
Abstract:
A cold rolling process for impressing a pattern on a surface of a sheet metal article involves passing the sheet article through a pair of rolls and engaging a patterning feature with isolated areas of a surface of the sheet article, at a localized pressure to plastically deform at least the surface of the sheet article. A rolling pressure is maintained on other areas of the sheet article that is less than the bulk elastic yield strength of the metal. A cold rolling apparatus is also described having a pair of rolls, each with partially cylindrical outer surfaces. The rolls have a gap between the cylindrical parts. One of the rolls has a localized surface region that is displaced relative to the surface of the roll. When the localized region is brought near the other roll, a spacing exists that is narrower than the gap. One of the rolls has a localized patterning feature that aligns with the localized surface region to impress a pattern into the sheet article. The gap allows the rolls to engage opposite surfaces of the sheet article while imparting compression less than a bulk elastic yield strength of the metal.
Abstract:
A method of electrochemically roughening an aluminium metal sheet for use as a lithographic plate support comprises subjecting the sheet in an electrolyte to an alternating current treatment. Treatment is performed in the presence of at least one added component, present in the sheet or in the electrolyte, selected from Hg, Ga, In, Sn, Bi, Tl, Cd, Pb, Zn and Sb. The added component accelerates the electrograining, so that only 35-75 kCoulombs per square metre of electricity is required.
Abstract:
An aluminium cell comprises an electrolysis region with a top reservoir and a sump below. Circulation of electrolyte is by convection. The cell is designed to continue operation past the point at which the electrolyte becomes saturated, and an aluminium hydroxide precipitate settles out by gravity in a stagnant lower region of the sump. The anode is preferably of an aluminium alloy containing magnesium, with tin present in the alloy or in the electrolyte. Batteries comprising stacks of such cells are also described.
Abstract:
The invention relates to a lid (10) for a garbage container (12). The body (14) forming the lid defines a chute formation (16) leading to an opening (20) through which garbage can be fed via the body into a garbage container on which the body is located, in use. The walls (32, 34) of the chute formation are associated with a magnet (18) that can trap metal objects. A flap (22), optionally also having a magnet (40) associated herewith, is pivotally mounted on the body to provide for blocking of the opening while garbage is not being fed into an associated garbage container. The lid is intended to be used with garbage containers into which leftovers of eating establishments are discarded, in order to trap tableware that often are simultaneously discarded.
Abstract:
There is provided a method of texturing a metal sheet or strip (8), which method comprises a plurality oF sequential texturing passes each of which is performed by passing the sheet or strip (8) between at least one pair of rollers (7), wherein at least one of each pair of rollers (7) has a textured pattern on the surface thereof and the textured patterns is transferred to the sheet or strip (8) during each texturing pass, and wherein the textured surface on the sheet or strip (8) resulting from each pass overlaps with that from the one or more other passes to form a final textured pattern. There is also provided an apparatus for texturing a metal sheet or strip (8).