Abstract: The invention provides the means to enhance in E. coli-based expression systems the formation of fusion polypeptides containing as an N-terminal tag a biotinylation polypeptide. By way of specifically exchanging in the nucleic acid sequence encoding the biotinylation polypeptide nucleotides at 11 discrete positions enhances the formation of the total fusion polypeptide by at least 40%.

Abstract: The invention relates to a method for the analysis and optimization of the expression efficiency in the preparation of a protein in expression systems and to a method for the preparation of proteins in such expression systems.

Abstract: A process for breaking down aromatics in industrial wastewaters that contain small amounts of aromatics by reaction with an ozone-containing oxygen stream at a temperature of from 40 to 70° C. and at a pH of from 4 to 7, involves treating industrial wastewaters that contain small amounts of aromatics in two stages with an oxygen stream that contains from 5 to 8% by volume of ozone with thorough mixing by causing the wastewater to flow upward through two reaction zones, the overflow of the wastewater at the top of the first reaction zone entering the second reaction zone at the base, the purified wastewater being obtained at the top of the second reaction zone, the ozone-containing oxygen stream first entering at the base of the second reaction zone, and the waste gas obtained at the top of the second reactor being introduced at the base of the first reaction zone, and, furthermore, a gas containing less than 0.2% by volume of ozone being obtained at the top of the first reaction zone.

Abstract: The invention relates to an electromagnetic valve arrangement, preferably for a pressure medium of a vehicle braking system, comprising an electromagnet arrangement which is coupled with a valve closing means which can be brought into several positions, a housing with a first, a second, a third, and a fourth connection of which, in a first position, the first and the second connection are in flow connection with each other, and the third and the fourth connection are blocked; in a second position, the first, the second, the third, and the fourth connection are blocked; in a third position, the first and the second connection are blocked, and the third and the fourth connection are connected with each other; and in a fourth position, the first and the third connection are connected with each other, and the second and the fourth connection are blocked.

Abstract: The invention relates to an electronically controllable braking system for motor vehicles with a brake pressure generator unit (2) which can be actuated by a brake pedal (1), which supplies hydraulic fluid via a hydraulic fluid path (3) to at least one wheel brake (4) of the motor vehicle, a first electromagnetic valve arrangement (5a, 5b) which is arranged in the hydraulic fluid path between the brake pressure generator unit (2) and the wheel brake (4) for controlling the pressure build-up, pressure relief and pressure holding phases in the wheel brake, a motor-powered controllable hydraulic pressure source (7) which, in addition to or in lieu of the brake pressure generator unit (2), supplies hydraulic fluid to the wheel brake (4), and a motor-powered controllable auxiliary energy source (15, 30) which boosts an actuation of the brake pressure generator unit (2) by the brake pedal (1) or which effects an actuation of the brake pressure generator unit (2) in lieu of the brake pedal (1), with the controllable

Abstract: An anti-lock braking method to retard the wheels of a vehicle provides thatbrake pressure be augmented or reduced or maintained constant in response to slip and/or the change in the rotational speed (positive or negative deceleration) of a retarded wheel as related to at least one threshold value, andthe respective renewed accelerations of the retarded wheels be measured during successive control cycles of the anti-lock braking so as to raise the threshold value or prevent a reduction of the brake pressure for a predetermined period of time in order to suppress undesired control operations which are releasable above all by oscillations of the vehicle axle.

Abstract: Preparation of .alpha.,.omega.-aminoalcohols of the general formula IHO--CH.sub.2 --X--CH.sub.2 --NH.sub.2 (I),in which x denotes a C.sub.1 -C.sub.20 -alkylene chain optionally substituted by inert radicals and/or optionally interrupted by oxygen or nitrogen,by the reaction of .alpha.,.omega.-alkanediols of the general formula IIHO--CH.sub.2 --X--CH.sub.2 --OH (II),in which the connecting member x has the meanings stated above, with ammonia and a catalyst at a temperature ranging from 150.degree. to 300.degree. C. and under a pressure of from 50 to 300 bar, wherein the catalyst used is one whose catalytically active material consists of iron to an extent of from 5 to 100% w/w.

Abstract: In a method of controlling the brake pressure of a vehicle brake system equipped with anti-lock protection it is provided to measure the slip and/or rotational retardation of a wheel whose brake is applied and to compare each measured value with a given threshold value so as to lower the brake pressure if the threshold value proves to have been surpassed. Undesired pressure reductions can be avoided by increasing the threshold value for given periods of time from a basic value (S.sub.G) and subsequently decreasing it again. At a point in time T.sub.1 at which the rotational retardation of the braked wheel is greater than a value corresponding to a physically feasible slowdown of the vehicle the threshold value is increased abruptly, to be decreased thereafter according to a predetermined function of time. During the lowering of the threshold value the change in speed of the retarded wheel is measured over given intervals of time .DELTA.T and compared with the instantaneous higher threshold value.

Abstract: Ruthenium tetroxide is obtained by oxidation of an alkali metal ruthenate in aqueous solution. The oxidizing agent used is ozone. The oxidation is carried out at a pH greater than or equal to 8.

Abstract: 3-Dialkylaminopropionitriles ##STR1## where R.sup.1 and R.sup.2 are each C.sub.1 -C.sub.4 -alkyl which may furthermore be bonded to form a 5-membered or 6-membered ring, bis-(2-cyanoethyl) ether IINC--CH.sub.2 --CH.sub.2 --O--CH.sub.2 --CH.sub.2 --CN IIand, if desired, ethylenecyanohydrin IIIHO--CH.sub.2 --CH.sub.2 --CN IIIare prepared jointly by a process in which(a) acrylonitrile and water are reacted in the presence of a base at from 60.degree. to 150.degree. C. to give a mixture of acrylonitrile, water and bis-(2-cyanoethyl) ether II, the base being a mineral base, a quaternary nitrogen base or a mixture of these,(b) this mixture is reacted at about 0.degree.-50.degree. C.

Abstract: Cyclic N,N'-dimethylureas are prepared by catalytic hydrogenation of a cyclic urea which carries hydroxyl groups in the .alpha.-position to the two nitrogen atoms.

Abstract: N-substituted cyclic amines of the general formula I ##STR1## where A is an alkylene group or a --(CH.sub.2).sub.n --[--O--(CH.sub.2).sub.m ].sub.r group which may be monosubstituted or polysubstituted by radicals R without the radicals R in a defined compound having to be identical, R is alkyl, alkoxyalkyl, unsubstituted or alkyl-substituted or alkoxy-substituted cycloalkyl, cycloalkylalkyl, aryl or arylalkyl, n and m independently of one another are each from 2 to 8 and r is from 1 to 3, the --(CH.sub.2).sub.n --[O--(CH.sub.2).sub.m ].sub.r group consisting of from 5 to 12 members, are prepared by reacting a primary amine of the general formula IIR--NH.sub.

Abstract: 1-Alkyl- or 1-cycloalkylpiperazines are prepared by reacting piperazine with an alkanol or cycloalkanol in the presence of hydrogen and a hydrogenation/dehydrogenation catalyst by a process in which the reaction is carried out at from 130.degree. to 190.degree. C. under from 5 to 100 bar in the presence of from 5 to 40% by weight, based on the reaction mixture, of water, and the molar ratio of piperazine to alkanol or cycloalkanol is kept at from 1:1.5 to 1:8.

Abstract: Ethylene cyanohydrin (Ia) and its ethersR--O--CH.sub.2 --CH.sub.2 --CN Ib(where R is an organic radical) are prepared jointly by reacting an alcohol R--OH (II) with 2,2'-dicyanodiethyl ether (III) in the presence of a base.

Abstract: 1,3-Diamino-2,2-dialkylpropanes whose alkyl substituents are each of 1 to 4 carbon atoms are prepared by reacting the corresponding 2,2-dialkylpropane-1,3-diols with ammonia in the presence of hydrogen under superatmospheric pressure by a process in which the reaction is carried out in solution and in the presence of a cobalt-containing catalyst.

Abstract: A process for the preparation of 3-hydroxytetrahydrofuran by catalytic dehydration of butane-1,2,4-triol, in which a catalyst chosen from the group of the bleaching earths is used and the dehydration is carried out in the presence of not less than 3 moles of water per mole of butane-1,2,4-triol.

Abstract: N-Alkylpiperidines or N-alkylpyrrolidines are obtained by hydrogenating a corresponding N-alkyldicarboxylic acid imide over a fixed catalyst by first working to only partial conversion, for example of about 50%, and distilling off the required product together with water from the partially converted mixture, where appropriate with recycling of the unconverted remainder.

Abstract: A process for the preparation of a hydrogenation catalyst which contains the oxides of the metals nickel, copper, molybdenum and aluminum and/or iron, and may or may not contain manganese oxide, by precipitating a solution of salts of the metals with an alkali metal carbonate at from 35.degree. to 95.degree. C. and a pH of from 5 to 9 and heating the precipitate at from 350.degree. to 700.degree. C., the amount of the metal salts being selected so that the catalyst contains from 5 to 70 percent by weight of aluminum oxide and/or iron oxide, the remainder being principally nickel oxide and, based on nickel oxide, from 20 to 40 percent by weight of copper oxide, from 0.5 to 6 percent by weight of molybdenum oxide and from 0 to 10 percent by weight of manganese oxide.

Abstract: A process for the preparation of a hydrogenation catalyst which contains the oxides of the metals nickel, copper, molybdenum and aluminum and/or iron, and may or may not contain manganese oxide, by precipitating a solution of salts of the metals with an alkali metal carbonate at from 35.degree. to 95.degree. C. and a pH of from 5 to 9 and heating the precipitate at from 350.degree. to 700.degree. C., the amount of the metal salts being selected so that the catalyst contains from 5 to 70 percent by weight of aluminum oxide and/or iron oxide, the remainder being principally nickel oxide and, based on nickel oxide, from 20 to 40 percent by weight of copper oxide, from 0.5 to 6 percent by weight of molybdenum oxide and from 0 to 10 percent by weight of manganese oxide.

Abstract: An improved catalyst for the complete hydrogenation of acetylenically unsaturated alcohols and based on nickel, copper and manganese. The catalyst is used without a support and molybdenum is additionally included in an amount approximately equal to the content of manganese.