Abstract: There is disclosed a heat-sterilizable spiral-wound filtration module having an outer shell comprising a cord, fabric or laminate consisting of a heat-resistant rigid first polymer encased within a thermoplastic second polymer.

Abstract: There is disclosed a process and apparatus for testing the integrity of filter elements located in protected environments such as clean rooms and the like, principally characterized by wireless electromagnetic transmission of test data between the filter test apparatus located in the protected environment and data evaluation means located outside the protected environment. The process and apparatus are especially suitable for testing ultra- and micro-filtration filter elements.

Abstract: There is disclosed a method for grafting unsaturated monomers to nitrogen-containing polymers in an aqueous environment and in the presence of carbon tetrachloride and certain reducing agents.

Abstract: Fabrication of the surface-grafted microporous membranes by coating the membrane with an N-halogenated compound, followed by grafting with an unsaturated monomer and sodium dithionite in a primarily aqueous solution that may contain an organic halogen compound selected from carbon tetrachloride and trichloroacetic acid. The coating may be formed in situ and may be cross-linked.

Abstract: Disclosed is a balance with a first parallel guide (3, 3') which resiliently connector a load receiver (2) to an area (5, 5') fixed to the housing and which is resiliently deformed under the influence of the weight to be measured, and with a second, softer parallel guide (8) which is connected by its one end to the load receiver (2) and by its other (11) end via a force receiver which is at least approximately without displacement to the area (5, 5') fixed to the housing and which transfers as a result thereof a fraction of the force of the weight onto the force measuring receiver that both parallel guides (3, 3', 8) exhibit at least approximately the same height and the same length and are arranged close to one another laterally. The second parallel guide is advantageously locate between two partial areas (3, 5, and 3', 5') of the first parallel guide.

Abstract: Improved methods of rendering PVDF membranes hydrophilic are disclosed.

Abstract: There is disclosed a pressurizable filter module for aqueous media having a degassing feature, the improvement comprising the use of a hydrophobic membrane between the inlet plenum of the filter module and the pressure relief valve.

Abstract: The invention relates to a textile reinforced membrane filter wherein the membrane filter material and the textile reinforcing material are made from synthetic polymers of the same substance class. A method for the production of the textile reinforced membrane filters where the first contact time between the filter solution film and the textile reinforcement material is maintained between 0.1 and 15 seconds.

Abstract: Halogen-substitutable hydrogen atoms are linked to nitrogen atoms of a polymer, with ethylenically-unsaturated monomers. By using inorganic or organic hypohalogenites and/or organic N-halogen derivatives as halogenation means, hydrogen atoms on the nitrogen atoms of the polymer membranes or polymer formed materials are replaced by halogen atoms and part of these are removed by reducing agents in the presence of ethylenically unsaturated monomers, with radical grafting of these on to the nitrogen atoms, after which the remaining halogen atoms are removed by reducing agents in the absence of monomers.

Abstract: An electronic balance with a measured value receiver, a digital signal processing unit, a display unit and a calibrating device controlled by the digital signal processing unit (18) for placing on and lifting off a calibrating weight by use of a motor that the digital signal processing unit allows the calibrating weight to be continuously placed on and lifted off again and calculates the average value and the standard deviation from the individual measured values.

Abstract: In a filter device with a filter stack (32) which is held in sealing position by two end plates (9, 2). At least one of which comprises fluid connections (3, 4, 5), and consists of round flat-filter elements (41) and alternatingly arranged, congruent, draining support elements (38), the end plate (2) comprising the fluid connections (3, 4, 5) is part of a housing (1, 2) surrounding the filter stack (32) and the peripheral approach flow of the filter stack (32) takes place via an annular housing space (11). The filter stack (32) is penetrated approximately in the direction of its diameter by a slot-like shaft (30, 30') for the fluid guidance of the retentate which shaft empties in the end plate (2) comprising the fluid connections (3, 4, 5). At least one permeate shaft (31) for removing the permeate from the plane of the filter elements (41) is arranged in the diametric end area of the stack surface. The permeate shafts (31) empty in the end plate (2) with connections (3, 4, 5).

Abstract: A tubular filter element consisting of a filter leaf which is pleated and connected at both its fold ends to a hollow cylindrical filter body (F) both of whose front surfaces are sealed by end caps (11, 13), one end cap (13) of which opens, as a connection cap, the hollow core (10') for communication with a housing space (3) of a surrounding housing, the force flow guidance of the fluid to be treated takes place along the folds (10) through a tube (6', 5) which extends through the hollow core (10') of the filter body (F), rests on the fold edges of the filter body (F), is open at one end in the area of the fold range functioning as outlet or inlet (20), is tapered in the area of the fold range functioning as inlet or outlet (21) and forms a connection (5) for the recirculating flow of fluid coaxially to the connection cap (3) for the flow of fluid to be treated which cap establishes the housing communication.

Abstract: A balance with a system carrier (1) fixed to the housing and with a balance-scale support part (2) connected by two upper and two lower guide rod struts in the form of a parallel guide to the system carrier. Each upper guide rod strut is connected to a lower guide rod strut via two connection areas, which struts are combined to a guide rod plate (5,6). The two guide rod plates (5,6) are fastened laterally to the system carrier (1) and to the balance-scale support part (2). The system carrier (1) is wider than the balance-scale support part (2). The two screw attachment surfaces for the guide rod plates (5,6) on the system carrier (1) and on the balance-scale support part (2) form an angle with one another so that the system carrier (1), the two guide rod plates (5,6) and the balance-scale support part (2) form a trapezoid when viewed from the top.

Abstract: An electronic balance with a system carrier (1) fixed to the housing, a load receiver (2) with two guide rods (3/4) which function as parallel guide, connect the load receiver to the system carried in a vertically movable manner, with four protruding arms (5, 6) which are fastened to the load receiver (2) and carry supports points (7, 8, 9, 10) for a balance scale on their ends and with a low-travel measured value receiver (14, 15) which is loaded either directly by the force of weight acting on the balance scale or with the interpositioning of a translation lever (11). The protruding arms (5, 6) comprise a central recess (19, 20) in front of their ends (17, 18) so that an upper web (21, 23) and a lower web (22, 24) remain and form a parallel guide for the particular support point (7, 8, 9, 10) of the balance scale. Each of the four support points (7, 8, 9, 10) of the balance scale is associated with a wire strain gauge (27, 28, 29, 30) located on one of the associated webs (21, 23).

Abstract: A device for the determination of dry substance of specimens consists of a microwave heater (10) and of a balance (5) whose balance scale (4) is located within the microwave heating area (7). This device includes a rotary disk (1) located within the microwave heating area (7) which disk can receive several specimen containers (2) and by elevating means which can raise and lower one of the specimen containers (2) from the rotary disk (1) and place it on the balance scale (4). The elevating means consists e.g. of a lifting device (11) for the rotary disk (1).

Abstract: A balance with a wind guard moved by a motor whereby the position of movable walls of the guard are monitored by a sensor. An electronic memory is provided for the desired end position of the movable wall elements. The desired end position of the removable walls can be stored in this memory in a learning phase and when the walls are opened by the motor, they are opened only up to a preselected position. This minimizes the time for opening and closing the weighing area and diminishes exposure to air turbulence within the weighing area.

Abstract: There is disclosed an electric balance with a sensor (2), a digital signal processing unit (4), a digital display (5) and switching means (6) which suppress the leading zeros in the digital display by a control means (7) which activates and deactivates the switching means (6) for suppressing leading zeros as a function of the sign of the result of measuring. In this manner, a change of sign can be signaled more clearly. It is also possible to display more leading zeros as the magnitude of the deviation of the result of measuring from the value zero increases so that the leading zeros appear in several stages, starting from zero up to a set measuring value.

Abstract: The gravimetric control of a mass flow from or into a container located on a balance using a pulsating dosing pump, the output signal of the balance is digitally filtered in such a manner that the course in time of the mass flow is cyclically estimated from the filtered wighing signal. This estimated value of the course in time of the mass flow is used to calculate the course in time of an auxiliary mass flow which compensates the pulsation of the mass flow of the pulsating dosing pump and a speed course is calculated from the course in time of the auxiliary mass flow for driving an auxiliary dosing pump.

Abstract: An electronic balance with scale on top having a drive means for a magnetic agitator which integral onto the balance scale. This enables the work steps of agitating and weighing to be performed simultaneously and by the same device.

Abstract: In a method and a device for preventing or breaking down a filter covering layer during the filtration of liquids with finely distributed constitutents therein in a cross-flow operation in which the liquid to be treated is conducted in a narrow overflow slot (SP) between a filter surface (PM) and a slot limiter surface (FM), the slot limiter surface (FM) is brought adhesively into areal contact with the developing filter covering layer (DS) in a periodic manner by means of relative motion relative to the filter surface (PM) and the filter covering layer (DS) is removed in a rinsing fashion from the filter surface (PM) by reactivating the overflow slot (SP) and overflowing the filter surface (PM) and the slot limiter surface (FM). The movable wall is formed by a foil membrane consisting of plastic which is clamped on the edge in a sealing manner in a surrounding housing.