Abstract: A heat exchanger has a turbulating insert arranged between a pair of plates. The turbulating insert is permeable to fluid flow in both a high-pressure-drop direction and a low-pressure drop direction. One portion of the turbulating insert has the high-pressure-drop direction oriented at a non-zero angle to the high-pressure-drop direction of another portion. A method of making the heat exchanger includes forming a turbulating insert, removing a portion of the turbulating insert to create a cavity within the turbulating insert, placing the remaining turbulating insert into a stamped first plate, and placing the removed portion of the turbulating insert into the cavity at a non-zero angle of rotation relative to the remaining turbulating insert.

Abstract: A heat exchanger has a turbulating insert arranged between a pair of plates. The turbulating insert is permeable to fluid flow in both a high-pressure-drop direction and a low-pressure drop direction. One portion of the turbulating insert has the high-pressure-drop direction oriented at a non-zero angle to the high-pressure-drop direction of another portion. A method of making the heat exchanger includes forming a turbulating insert, removing a portion of the turbulating insert to create a cavity within the turbulating insert, placing the remaining turbulating insert into a stamped first plate, and placing the removed portion of the turbulating insert into the cavity at a non-zero angle of rotation relative to the remaining turbulating insert.

Abstract: An electrode for a liquid level sensor adapted for a determination of a liquid level of an electrically conductive liquid in a container is disclosed. The electrode comprises a first end configured for an electrically conductive contact with a sensor component of the liquid level sensor and a second end opposite the first end. The electrode is formed of one or more non-metallic materials of which at least one is an electrically conductive non-metal that is in electrically conductive contact with the first end of the electrode, wherein the at least one electrically conductive non-metal is configured for an electrically conductive contact with the electrically conductive liquid.

Abstract: A system and method for producing flat tubes is described and illustrated. The flat tubes can be produced from at least one strip of endless band material having at least one wall part and an inner part formed with corrugations on a roller train provided with roller pairs, with the strip running in a longitudinal direction through the rollers and being shaped. The inner part of the flat tube can be formed with corrugations placed between the shaped wall parts, after which the closure of the flat tube is carried out. Production of the flat tubes can include forming spaced apart band thinning lines running in the longitudinal direction of the strip, and forming corrugation peaks and corrugation troughs at the band thinning lines.

Abstract: A heat exchanger with a plurality of stacked flat tubes and a collecting tank having a wall extending around the entire periphery of, and connected to, the end of the stacked flat tubes. A first medium may be distributed through the collecting tank and flat tubes. Internal inserts are in the flat tubes, with the inserts being bonded between the broad sides of the tubes and, in the region of connection of the tubes to the collecting tank, being configured to compensate for length changes in the stacking direction caused by temperature changes, as by recesses in connectors such as wave flanks or by corrugated wave flanks. The flat tubes with inserts such as described may be separately provided for use in manufacture of heat exchangers.

Abstract: A number of flat tubes, flat tube heat exchangers, and methods of manufacturing both are described and illustrated. The flat tubes can be constructed of one, two, or more pieces of sheet material. A profiled insert integral with the flat tube or constructed from another sheet of material can be used to define multiple flow channels through the flat tube. The flat tubes can be constructed of relatively thin material, and can be reinforced with folds of the flat tube material and/or of an insert in areas subject to higher pressure and thermal stresses. Also, the relatively thin flat tube material can have a corrosion layer enabling the material to resist failure due to corrosion. Heat exchangers having such flat tubes connected to collection tubes are also disclosed, as are manners in which such tubes can be provided with fins.

Abstract: A system and method for producing flat tubes is described and illustrated. The flat tubes can be produced from at least one strip of endless band material having at least one wall part and an inner part formed with corrugations on a roller train provided with roller pairs, with the strip running in a longitudinal direction through the rollers and being shaped. The inner part of the flat tube can be formed with corrugations placed between the shaped wall parts, after which the closure of the flat tube is carried out. Production of the flat tubes can include forming spaced apart band thinning lines running in the longitudinal direction of the strip, and forming corrugation peaks and corrugation troughs at the band thinning lines.

Abstract: A heat exchanger with a plurality of stacked flat tubes and a collecting tank having a wall extending around the entire periphery of, and connected to, the end of the stacked flat tubes. A first medium may be distributed through the collecting tank and flat tubes. Internal inserts are in the flat tubes, with the inserts being bonded between the broad sides of the tubes and, in the region of connection of the tubes to the collecting tank, being configured to compensate for length changes in the stacking direction caused by temperature changes, as by recesses in connectors such as wave flanks or by corrugated wave flanks. The flat tubes with inserts such as described may be separately provided for use in manufacture of heat exchangers.

Abstract: A microtiter plate for blood typing consisting of a flat-bottomed plate of rigid transparent polystyrene having a plurality of wells, the polystyrene being surface treated by a corona and/or plasma method of applying high power electric energy at high frequency resulting in a permanently measurable negative ion-charge at the surface of the wells, and layers of substantially pure antiserums dried on the wells without any binder from a suspension or solution of the antiserums and tightly but releasably bound to the polystryene.

Abstract: In a device for testing air for microorganism content with a rapidly rotating impeller inside a cylinder that has a backing sheet coated with culture medium against its inside surface, microorganisms that vary more extensively in size can be detected with almost equal effectiveness, the throughput of air can easily be determined, and the precipitation effect can be precisely tested because the backing sheet rotates along with the impeller, the blades of the propeller are at a low angle to the plane it rotates in, the air enters at a location that is separate from the location at which it leaves, through inlets from above and down and out through outlets, and the inner surface of the rotor below the impeller chamber is in the form of a channeling cylinder.