Abstract: The invention relates to a PEM fuel cell which has a new type of edge structure, in which a reservoir of water is formed in a minute gap between membrane and edge seal, which considerably improves the utilization time of a polymer electrolyte membrane, in particular with dry process gases.

Abstract: A process for recovering and purifying substituted benzenesulfonates, by neutralizing a mixture including at least one substituted benzenesulfonate, or at least one corresponding substituted benzenesulfonic acid, and sulfur trioxide, sulfuric acid and/or hydrogen chloride in free or bound form, in an aqueous phase using an alkali metal hydroxide, and purifying it in this aqueous phase, and by subsequently separating the substituted benzenesulfonate(s) from this aqueous phase. The mixture is comminuted into particles having a Sauter mean diameter in the range from 1 &mgr;m to 2 cm, either before or during introduction into this aqueous phase.

Abstract: The invention relates to a method and a device for separating at least two physical areas (1, 2) and for reducing the transmission of air-borne particles between said physical areas so as to protect persons and/or products (26) from said air-borne particles. The persons is located at least partly in the first physical area (1) and the products (26) in the second physical area (2) and at least one flat jet (13) of purified air is used to separate the two areas. The invention is characterized in that at least one low-turbulence displacement air stream (14) of purified air is generated at least in the second physical area (2) near the at least one air jet (13) and said at least one displacement air stream is directed primarily in the same direction as the at least one air jet (13).

Abstract: The invention relates to a controlled release tablet which in part or as a whole contains water-insoluble linear polysaccharides, preferably the polysaccharide poly(1,4-&agr;-D-glucan), in the form of microparticles, as retardation material. The tablet is also capable of controllably releasing an active agent.

Abstract: The invention relates to a process for the comminution of bulk materials comprising synthetic polymers which do not have an elastomeric behavior by mechanical, thermal or electromagnetic loading of the bulk materials, which comprises treating the bulk materials, before and/or during the loading, with oxidants which have a redox potential of greater than 1.5 V or subjecting them to corona, UV or plasma treatment without complete oxidation of the synthetic polymer taking place.

Abstract: Process and apparatus for the continuous preparation of polymers Two reaction partners (starting materials) are stored in separate reservoirs 2, 3, 4 and 5 and are transported using overpressure via heated heat exchangers 11, 12 into a micromixer 18 by means of control and metering devices 6, 7, which can be metering pumps. In the heat exchangers 11, 12, the starting materials are heated, separately in each case, to the extent that during the mixing operation in the micromixer 18 the required reaction temperature is immediately reached. The polymerization takes place in a downstream tube reactor 20 which consists of tubes 21, 22, 23 which are connected in series.

Abstract: The invention relates to a method for removing fluorinated emulsifying agent acids from waste waters, characterized in that the finely dispersed solids in the waste water are stabilized with a nonionic or cationic surfactant or an analogous acting surface active substance, the fluorinated emulsifying agent acids are subsequently bonded on an anion exchange resin and the fluorinated emulsifying agent acids are eluted from the latter.

Abstract: Triptycene derivatives, and their use for opto-electronic applications, in particular as electroluminescent materials Triptycene devices of the formula (I) where the symbols in the formula have the following meanings: K1, K2 and K3 are identical or different and are mono- or polycyclic systems, which may, if desired, contain heteroatoms, preferably N, S and/or O, and; X and Y are identical or different and are CR1, N, P, As or SiR2; R1 are identical or different and are H, halogen, pseudohalogen or a hydrocarbon radical having 1 to 30 carbon atoms, which may also, if desired, contain heteroatoms, preferably —O—, —N— and/or —S—; R2 are identical or different and are a hydrocarbon radical having 1 to 30 carbon atoms, which may also, if desired, contain heteroatoms, preferably —O—, —N— and/or —S—, are suitable for use in electroluminescent devices.

Abstract: The invention relates to dendrimeric fullerene derivatives in which the fullerene is linked to at least one dendron, wherein the or each dendron has at least one protic group which imparts water solubility.

Abstract: The invention relates to a process for the preparation of bipyridyls by converting at least one pyridine of the formula (III) in which S′, S″, S′″, S″″ and S′″″, independently of one another, are identical or different and are hydrogen, (C1-C18)-alkyl, alkoxy-(C1-C18), acyloxy-(C1-C18), aryloxy-(C1-C18), perfluoroacyloxy-(C1-C8), NO2, (C1-C18)-aryl, (C1-C18)-heteroaryl, halogen, hydroxyl, nitro, nitroso, CN, COOH, CHO, PO3H2, SO3H, SO2R, SOR, NH2, NH-alkyl-(C1-C18), N-alkyl2-(C1-C18), protected amine, CF3, NHCO-alkyl-(C1-C4), N-alkyl-(C1-C4)-CO-alkyl-(C1-C4), COO-alkyl-(C1-C18), CONH2, CO-alkyl-(C1-C18), NHCOH, NHCOO-alkyl-(C1-C4), CO-(C1-C18)-aryl, COO-(C1-C18)-aryl, CHCH-CO2-alkyl-(C1-C18), CHCHCO2H, PO-phenyl2, PO-alkyl2-(C1-C4), (COO−)n(cation)n+, (PO32−)n(cation)2n+, (SO3−)n(cation)n+ and/or (O−)n(cation)n+, where optionally S′, S″, S′″, S″″ and/or S&pr

Abstract: A process for recovering and purifying substituted benzenesulfonates, by neutralizing a mixture including at least one substituted benzenesulfonate, or at least one corresponding substituted benzenesulfonic acid, and sulfur trioxide, sulfuric acid and/or hydrogen chloride in free or bound form, in an aqueous phase using an alkali metal hydroxide, and purifying it in this aqueous phase, and by subsequently separating the substituted benzenesulfonate(s) from this aqueous phase. The mixture is comminuted into particles having a Sauter mean diameter in the range from 1 &mgr;m to 2 cm, either before or during introduction into this aqueous phase.

Abstract: The invention relates to a process for separating off ethylene from a gas mixture comprising more than 8% by volume of carbon dioxide or oxygen, by gas permeation.

Abstract: Polymer-stabilized metal colloid solutions, process for preparing them and their use as catalysts for fuel cells. Process for preparing metal colloid solutions by reacting a platinum compound and, if desired, one or more compounds of Rh, Ru, Ir or Pd with a reducing agent. At least one cation-exchange polymer is used for stabilizing the metal colloid solution.

Abstract: A process for preparing aldols by catalytic reaction of aldehydes and/or ketones comprises conducting said reaction in the channels of a microstructured reaction system.

Abstract: The invention relates to an apparatus for preparing a rapidly solidifying mixture from a plurality of liquid components and subsequent atomization of the solidifying mixture. The apparatus comprises a mixing chamber (4), a liquid distributor (1′,7) and N identical, droplet-forming nozzles (9a,9b) connected to the liquid distributor. The liquids to be mixed can be fed separately to the mixing chamber and the mixing chamber has neither significant back-mixing in the areas in which reactions can occur, nor significant dead spaces in the flow in these areas. The liquid distributor (1′,7) is connected to the mixing chamber and divides the mixed stream coming from the mixing chamber equally over the nozzles (9a,9b) without significant back-mixing or dead spaces in the flow, so that the flow properties of the partial streams and their residence time in the liquid distributor are identical.

Abstract: The invention relates to a process for preparing carbonyl compounds from olefins and an oxidizing agent in which the olefin is oxidized in a reactor, a reaction gas mixture which comprises unoxidized olefin being formed, which comprises separating off unoxidized olefin at least in part from the reaction gas mixture by a membrane process.

Abstract: The invention relates to a process for the catalytic pyrolysis of acetic acid for preparing ketene and/or secondary products, which comprises spraying, as catalyst, phosphoric acid in the form of a liquid jet into the acetic acid vapor.

Abstract: The invention relates to a process for preparing carbonyl compounds from olefins and an oxidizing agent in which the olefin is oxidized in a reactor, a reaction gas mixture which comprises unoxidized olefin being formed, which comprises separating off unoxidized olefin at least in part from the reaction gas mixture by a membrane process.

Abstract: The invention relates to a method for obtaining fatty acid esters and fatty acids, preferably unsaturated fatty acid ethyl esters, from biological sources by continuous, combined in-situ extraction, reaction and chromatography. The invention is characterized in that simultaneously and in the same location, in the presence of a compressed gas and an 0.5-5 % stream of lower alcohols as modifiers and in the presence of an inert catalyst, the fatty acids are fully transesterified from their native fatty acid sources, which are selectively desorbed and eluated in the conditions specified above.

Abstract: Continuous, chaotic convection mixer, convection heat exchanger and convection reactor The invention relates to a device (1), in particular for mixing, for heat exchange or for carrying out reactions, having one or more through-flow elements (2) which have a center line (3) in the direction of flow, wherein the element(s) (2) is/are at least partially shaped or arranged such that the curve (9) formed by the center line(s) (3) approximately satisfies the following parametric representation: ϑ ⁡ ( t ) = ( ( - 1 ) [ t ] ⁢ a ⁡ ( t