Abstract: The invention relates to a method for treating biomaterial using at least one electrical field generated by a first voltage pulse which is terminated once the value for an electrical parameter has exceeded or dropped below a preset limit. After the first voltage pulse has been terminated, it is continued by an additional voltage pulse. The invention also relates to a circuit arrangement comprising at least one storage device for electrical charges to generate at least one voltage pulse by selectively discharging the storage device, and at least one control unit for controlling the discharge. The present invention provides a controller for monitoring the chronological progression of the voltage pulse. This controller controls at least one continuation of discharge after termination.

Abstract: Aqueous formaldehyde solutions are prepared and the formaldehyde content of the aqueous formaldehyde solutions produced is determined by an online analytical method. The desired formaldehyde content can subsequently be established by addition of water so that an aqueous formaldehyde solution having a defined formaldehyde content (formalin) is obtained.

Abstract: Disclosed is a device for processing biological material which at least comprises a chamber at least closable to the outside and having an inner space for receiving the biological material. The chamber comprises at least one electrode placed in contact with the inner space for generating an electric field. Also disclosed is a method for processing biological material. The biological material is introduced into the inner space above and the electrode can generate an electric field after said biological material is introduced by applying voltage to said electrode and a further electrode in contact with the inner space. The chamber comprises at least one inlet line having at least one opening arranged close to the electrode. The biological material is almost completely rinsed out of the inner space after the electric field is generated, via a solution guided via an inlet line of the chamber along at least one electrode.

Abstract: Disclosed is a method for treating biological material via electrical current, in which the biological material is added to a small volume of a buffer solution having relative high ionic strength. A strong electrical field is generated in the buffer solution by a high voltage pulse having a preset duration. The biological material is added to at most 50 ?l of a buffer solution with an ionic strength of at least 100 mmol/l. By at least one voltage pulse having a preset duration of at least 10 ?s, an electrical field with a field strength of at least 1 kV/cm is generated in the buffer solution. The voltage pulse is hereby interrupted at least once for a duration of at least 100 ?s and is then again continued.

Abstract: The invention relates to a container 20, 30 for receiving an aqueous solution, which is formed at least partially by an outer limit 21 forming an inner chamber 22, 32 for receiving the solution, and which comprises at least one area which acts as an electrode 25, 26, 33, 34 when an electric voltage is applied and a subsequent discharge occurs, wherein at least one electrode 25, 26, 33, 34 is made of a conductive synthetic material at least based on a plastic material which is doped with at least one conductive substance. A container 20, 30 of the above-mentioned kind is created this way, which is simple and economical to produce and also, for example, enables an efficient transfection of living cells by means of electroporation or an effective electrofusion.

Abstract: A device for grounding electrical components arranged in a chain has a grounding point at ground potential and an actuation device connected to the grounding point for connecting the electrical components to the grounding point. In order to provide such a device, with which a simple, safe, and durable grounding is obtained, the actuation device is constructed as a moving part extending in a longitudinal direction and movable in a longitudinal direction. The moving part has an electrically conducting grounding section connected to the grounding point and an electrically nonconducting insulating section arranged on the end of the moving part facing away from the grounding point.

Abstract: The invention relates to a method for determining the isomer composition in an isocyanate isomer mixture, wherein a spectrum of the isomer mixture is recorded and the spectrum is entered into a chemometric calibration model.

Abstract: An arrangement comprises a housing, in particular of a cooling and/or freezing device, a door which is articulated to the housing so as to be pivotable about a pivot axis of a hinge, and at least one drive device for pivoting the door relative to the housing, with the drive device comprising a drive unit by means of which a moment is exertable on the door relative to the hinge axis via at least one force transmission means.

Abstract: A screwing station, in particular along an assembly line, comprises at least one machine frame and a screwing tool adjustably supported relative thereto between at least one retracted and one operative position and connected to a supply and, optionally, a measuring line. To improve a screwing station of this type in such a way that less mass has to be moved while the screwing station is of a simple construction, so that wear, maintenance work and energy consumption are reduced and a concurrent movement of supply and measuring lines is prevented at the same time, which might otherwise result in damage to the lines, the screwing tool comprises a drive shaft supported on the machine frame and a wrench head telescopically displaceable relative to said shaft, the drive shaft and wrench head being drivingly connected and the wrench head being movable by means of a lifting and lowering means between retracted and operative position.

Abstract: The invention relates to a buffer solution for suspending animal or human cells and for dissolving biologically active molecules in order to introduce biologically active molecules into cells using an electric current. The inventive buffer solution has a buffering capacity of at least 20 mmol?1×pH?1 and an ionic strength of at least 200 mmol×1?1 during a change to the pH value from pH 7 to pH 8 and at a temperature of 25° C. The use of a buffer solution of this type allows biologically active molecules to be introduced into animal and human cells with a high degree of transfection efficiency and at the same time a low cell mortality. Different cell types, in particular dormant and actively dividing cells of low activity, can be successfully transfected in the buffer solution.

Abstract: The invention relates to an active impact protection system (1) for a knee area and/or a lower leg area of a vehicle occupant in a motor vehicle, particularly in a passenger car. The impact protection system (1) comprises an impact element (2) that can be extended toward the vehicle occupant out of a passive position and into an active position by means of a drive device (4). A particularly advantageous design results when the impact element (2) is formed by a lid of a passenger-side glove compartment (3).

Abstract: The invention relates to a process for the production of di- and polyisocyanates of the diphenylmethane series and mixtures thereof, in which aniline and formaldehyde are reacted in the presence of an acid catalyst to form di- and polyamines of the diphenylmethane series; the di- and polyamines of the diphenylmethane series are phosgenated, optionally in the presence of a solvent, to obtain a crude di- and polyisocyanate; from the crude di- and polyisocyanate, at least one fraction containing at least 5 wt. % 3-ring and multi-ring MDI and at least one fraction containing at least 95 wt. % 2-ring MDI are separated by distillation, and the acidities of the fraction containing at least 5 wt. % 3-ring MDI and multi-ring MDI, and/or the fraction containing at least 95 wt. % 2-ring MDI are determined analytically; and an acidic compound is added to the fraction containing at least 5 wt. % 3-ring MDI and multi-ring MDI, and/or the fraction containing at least 95 wt.

Abstract: Disclosed is a method for treating biological material via electrical current, in which the biological material is added to a small volume of a buffer solution having relative high ionic strength. A strong electrical field is generated in the buffer solution by a high voltage pulse having a preset duration. The biological material is added to at most 50 ?l of a buffer solution with an ionic strength of at least 100 mmol/l. By at least one voltage pulse having a preset duration of at least 10 ?s, an electrical field with a field strength of at least 1 kV/cm is generated in the buffer solution. The voltage pulse is hereby interrupted at least once for a duration of at least 100 ?s and is then again continued.

Abstract: The present invention relates to a process for the preparation of di- and polyamines of the diphenylmethane series, and to the preparation of di- and poly-isocyanates of the diphenylmethane series from these di- and poly-amines. The di- and poly-amines of the diphenylmethane series are prepared by the reaction of aniline and formaldehyde in the presence of hydrochloric acid. In with the present invention, the hydrochloric acid employed contains less than 0.001 wt. % of metal ions which are divalent and/or more than divalent.

Abstract: The invention relates to a method for treating biomaterial using at least one electrical field generated by a first voltage pulse which is terminated once the value for an electrical parameter has exceeded or dropped below a preset limit. After the first voltage pulse has been terminated, it is continued by an additional voltage pulse. The invention also relates to a circuit arrangement comprising at least one storage device for electrical charges to generate at least one voltage pulse by selectively discharging the storage device, and at least one control unit for controlling the discharge. The present invention provides a controller for monitoring the chronological progression of the voltage pulse, said controller controlling at least one continuation of discharge after termination.

Abstract: A process for preparing a shell-type catalyst which comprises applying to a substantially nonporous inorganic support material having a BET surface area of <80 m2/g, a catalytically active outer shell of a suspension containing at least one water soluble noble metal compound and a substantially water insoluble coating compound, drying the suspension onto the support material, and activating the coated support material in a reducing gas stream.

Abstract: Polyisocyanates of the diphenylmethane series are produced by a) reacting aniline and formaldehyde in the presence of an acidic catalyst to produce a polyamine, b) neutralizing the reaction mixture from step a) with a base at a temperature of more than 110° C. or neutralizing the reaction mixture from step a) with a base and heating the neutralized mixture to a temperature of more than 110° C., and c) phosgenating the polyamine from step b) to convert it to the corresponding polyisocyanate.

Abstract: The present invention concerns a process for the production of methylenedianiline (MDA) having a high monomer content.

Abstract: The invention relates to a method for continuously or discontinuously producing tetrahydrofuran polymers by homopolymerization of tetrahydrofuran, alkyl-substituted tetrahydrofurans and/or alkylene oxides in the presence of carboxylic acid anhydrides or compounds containing reactive hydrogen using an optionally non-acidified or acid-activated calcined and granular natural amorphous aluminum silicate catalyst. The inventive method provides a means for substantially suppressing the formation of cyclic ethers and for obtaining a polymer with a narrow molecular weight distribution by keeping the concentration of carboxylic acid anhydrides or alkylene oxide constantly below 1 wt. % during polymerization. The catalysts have a long life span and lead to polymers that are characterized by highly uniform properties and a narrow molecular weight distribution even if a fairly impure monomer is used.

Abstract: A thermoplastic trim strip is mounted to an edge face of a wood-core furniture panel by applying a face of the trim strip directly to the edge face and bonding the trim-strip face directly to the panel-edge face. The panel has outer faces terminating at the edge face and the trim strip is provided with edge lips that project past the broad faces when the strip is bonded to the edge face. The edge lips are melted over onto the panel faces and trimmed off where they project past the panel faces. A thin layer of glue can be applied between a face of the trim strip and the edge face and the trim-strip face is bonded to the panel-edge face by means of the glue layer.