Abstract: A balance with a wind guard moved by a motor whereby the position of the moveable walls of the guard are monitored by a sensor. An electronic memory is provided for the desired end position of the moveable wall element. 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. This intuitively and flexibly assigns wall elements to user keys.

Abstract: There is disclosed a membrane process for the purification of nucleic acids in aqueous solutions whereby a lasting reduction of endotoxin content is achieved. The process is suitable for small or large volumes and can be carried out quickly and with simple apparatus.

Abstract: The hydrophilicity of porous separation membranes is maintained by bonding the membranes to thermoplastic fiber substrates at least on their peripheries before the membrane peripheries are sealed in a thermoplastic resin. The membranes are capable of being integrity tested.

Abstract: There is disclosed a filtration unit for separating a substance from a fluid, the unit made up of at least one pleated filter element in a cylindrical housing, the housing in turn made up of two mating housing components and at least two fluid connectors, the filter element separating the housing into inlet and outlet plenums with the periphery of the filter element adjoining the wall of the cylindrical housing; the periphery of the filter element and the periphery of the two mating components are all bonded to each other by a single integral sealant bond.

Abstract: An apparatus for determining the position of the center of gravity of a test body with a test-body receiving plate supported on at least two weighing systems with short displacement in which device the position of the center of gravity is calculated from the particular bearing forces on the weighing systems that the connection between the test-body receiving plate (2) and the weighing systems (12, 13) takes place by means of coupling elements (22, 23) which are permanently connected by their one end to the test-body receiving plate (2), which are connected permanently by their other end to a weighing system (12, 13) and which are designed to be elastically flexible by means of at least one thin area (33, 34) defining a horizontal axis of rotation. This avoids an undefined introduction of force possibly overlaid by frictional forces and frictional moments into the weighing systems and thus increases the measuring accuracy.

Abstract: A filtration unit for the separation of substances from liquids utilizes a rotatable cylindrical module with a permeable wall disposed within a housing. A filter element which has at least one band of microporous membrane adsorber having a specific adsorption affinity for the substances to be separated is disposed within the cylindrical module so that the membrane absorber is abutted to the cylindrical module. The filter element encircles the feed inlet and can be in the form of an endless loop. A permeate plenum lies between the cylindrical module and the housing. The cylindrical module includes a liquid impermeable end cap which is provided with a coupling member adapted for connection to a drive of variable rotational speed.

Abstract: A filter dispenser for the storage and dispensation of individual flat filter sections. The filter dispenser includes a storage compartment with a slot shaped exit for a tube-like band, composed of two parts, and guides in proximity to the slot for the running through of the band parts. The two parts of the band are joined by continuous and releasable edges and cross connections which form pockets which seat filter sections. Upon simultaneous drawing of the parts of the band through the guides, the connections of the band between the guides and the storage compartment are broken and the encapsulated filter sections are released for removal.

Abstract: A method of separating albumin from serum by ion exchange chromatography with membrane adsorbers characterized by high productivity and yields of high purity albumin. The separation of the albumin is carried out on highly basic anion exchange membranes and on highly acidic cation exchange membranes. The albumin fraction can be eluted from the anion exchange membrane such that it can be fed directly to the cation exchange membrane without any special conditioning and the albumin can be extracted therefrom as an end product.

Abstract: In an electronic balance for loading having a balance scale (3) weighing system, display (19), control keyboard (21 to 26) and a digital processing electronic circuitry in which circuitry at least one memory is present for the weighed value shown in the display (19). A first additional key (25) is present in the control keyboard (21 to 26) upon the actuation of the key the weighed value shown in the display (19) and stored in the digital signal processing electronics is decreased and upon the first actuation of the key the weighed value displayed immediately previously is taken in addition into a first additional memory. Furthermore, a second additional key (24) is present in the control keyboard (21 to 26) upon whose actuation the weighed value displayed in the display (19) is taken into a second additional memory. By means of the decreasing key the balance operator can decreased the display from the too large actual value step-by-step to the correct theortical value.

Abstract: The invention relates to an electronic balance for use in an explosive environment. The invention calls for an intrinsically safe cable (1) which contains data lines in addition to the voltage supply lines. The data is serially transferred on the data lines.

Abstract: In an electronic balance for loading having a balance scale (3), weighing system, display (19), control keyboard (21 to 26) and a digital processing electronic circuitry in which circuitry at least one memory is present for the weighed value shown in the display (19). A first additional key (25) is present in the control keyboard (21 to 26) upon the actuation of the key the weighed value shown in the display (19) and stored in the digital signal processing electronics is decreased and upon the first actuation of the key the weighed value displayed immediately previously is taken in addition into a first additional memory. Furthermore, a second additional key (24) is present in the control keyboard (21 to 26) upon whose actuation the weighed value displayed in the display (19) is taken into a second additional memory. By means of the decreasing key the balance operator can decreased the display from the too large actual value step-by-step to the correct theortical value.

Abstract: An electronic balance with a balance scale (3) which is movably connected by a parallel guide consisting of an upper (4) and a lower guide rod (5) in a vertical direction to a system carrier (1) fixed to the housing, with at least two wire strain gauges (15) which are arranged in the vicinity of the ends of a guide rod (4), which ends are on the housing side, and which wire strain gauges measure the horizontal forces in the guide rod (4) which are caused by the torque transferred from the balance scale (3) onto the parallel guide, and with electronics which corrects the weight value emitted from the weighing receiver on the basis of the output signals of the wire strain gauges (15) and from stored comer-load correction factors that at least one of the guide rods (4) is supported on its housing-side end on an intermediate piece (18), that this intermediate piece (18) is connected by at least one approximately vertical thin web (13) and by a horizontal thin web (14) to the system carrier (1) fixed to the housin

Abstract: A toploaded balance in accordance with the principle of the electromagnetic compensation of force with a divided upper guide rod (3, 3') and a divided lower guide rod (4, 4') which together as a parallel guide connect a load receiver (2) to a system carrier (1) fixed to the housing, which system carrier (1), load receiver (2) and guide rods (3, 3', 4, 4') form a one-piece base, with a translation lever (5) rotatably mounted by two flexible articulations (7) on the system carrier (1), with a coupling element (12) connected by flexible articulations on the one hand to the load receiver (2) and on the other hand to the short lever arm of the translation lever (5), with a magnet build, as viewed from above, into the free space between the parts of the guide rods (3, 3', 4, 4') and their extensions on the system-carrier side and with a coil fastened on the longer lever arm of the translation lever (5) and extending into the air gap of the magnet, the translation lever (5), the two flexible articulations (7) for mo

Abstract: A process for cross-linking a cellulose hydrate membrane by use of a water-soluble diepoxide in an alkaline solution. The membrane so produced is highly resistant to attack by alkalis, acids and cellulases, and is readily regenerable by alkaline cleaning.

Abstract: A lop loaded balance with a load receiver (1, 2, 3) connected by at least one upper (11) and at least one lower guide rod in the form of a parallel guide to a system carrier (4) fixed to the housing, which load receiver, guide rods and system carrier are manufactured from one piece. The system carrier (4, 5, 6, 7) is designed as a frame. The frame-like system carrier is completely surrounded by a second frame (14, 15, 16, 17) supported on the balance feet and that both frames are constructed in a one-piece manner and are connected to one another in such a manner that twistings of the one frame are transferred as little as possible onto the other frame.

Abstract: There is disclosed a composite isotropic cellulose nitrate membrane on a polyester support and a method of making the same, the membrane having particular utility as various types of reagent-containing test strips for use in analytical chemistry and medicinal diagnostics.

Abstract: A dead-end filtration unit without a housing comprising at least one filter cassette, each cassette comprising a plurality of laminar sections of porous adsorptive membrane, which have been rendered fluid-impermeable on their peripheries, the cassettes being sealingly compressed between two filter retainers fitted with feed inlet and permeate outlet and wherein the laminar sections are made of the same or different membrane adsorber types.

Abstract: It is suggested for a balance with one or several weighing cells (1-4, 31) with a total of at least eight wire strain gauges (D.sub.1 -D.sub.4, S.sub.1 -S.sub.4), four of which (D.sub.1 -D.sub.4) are expanded under load and four (S.sub.1 -S.sub.4) compressed under load, in which the eight wire strain gauges are connected together circularly in series so as to form a single Wheatstone bridge which is supplied with voltage along a diagonal (12, 13) (vertical diagonal) and the output signal is taken off along the other diagonal (14, 15) (horizontal diagonal) that a signal is additionally tapped off along the upper horizontal chord (16, 17) and along the lower horizontal chord (18, 19). This makes possible a corner-load adjustment for the balance utilizing the additional signals.

Abstract: There is disclosed a filtration unit for the selective separation of substances from fluids by membrane adsorbers, comprising a plurality of filtration chambers arranged in parallel and using membrane adsorber packs having a variable number of porous laminar sections, and wherein at each membrane adsorber pack, the same pressure drop is maintained between feed and permeate.

Abstract: Multi-step methods of making a non-skinned isotropic microfiltration membrane, the common steps of which include heating a PVDF-type casting dope above its cloudpoint, forming a film, and immersing the film in a gelation bath.