Abstract: Compounds of formula I ##STR1## wherein X and Y each denotes hydrogen or together denote -0-,R.sub.1 denotes allyl optionally substituted by 1 to 3 alkyl groups, the substituent or substituents having in total a maximum of 3 carbon atoms, cyclopropyl-methyl or 3-furylmethyl,R.sub.2 denotes hydrogen, alkyl with 1 to 10 C-atoms, cycloalkyl with 5 or 6 carbon atoms, optionally substituted phenyl or optionally substituted phenyl-alkyl with 7 to 12 C-atoms,R.sub.3 denotes hydrogen, alkyl with 1 to 10 C-atoms or phenyl,R.sub.4 denotes hydrogen, OH, NR.sub.6 R.sub.7, NHCOR, NHSO.sub.2 R' or NHCOOR",R.sub.6 and R.sub.7, independently of one another, denote hydrogen or alkyl with 1 to 3 C-atoms,R denotes alkyl with 1 to 6 C-atoms, phenyl or --A--COOR",A denotes alkylene or alkenylene each with 2 to 4 C-atoms,R' denotes alkyl with 1 to 6 C-atoms or phenyl,R" denotes methyl or ethyland wherein either R.sub.3 is in the .alpha.-positionand R.sub.4 is in the .beta.-position, or R.sub.3 is in the .beta.position and R.sub.

Abstract: According to the invention, the grains of the hydrate slurry are separated by sedimentation where the dispersed bubbles of air are removed in course of the presizing, then a supplementary sizing is carried out. Preferably, a liquid free from hydrate grains is fed in to stream against the sinking grains. This liquid is advantageously the spent liquor of the hydrate filter. The apparatus according to the invention consists of a container with conical bottom, a feeding device, a slurry outlet stub and an overflow channel. The inlet stubs of the feeding device, however, are placed off-center and every stub is connected with a presizing equipment. This equipment is composed of a bundle of pipes and/or a pack of plates which are slop placed to geometrical axis: At the upper part of the presizing equipment there is a foam overflow apparatus. The bottom of each presizing equipment is connected with a common cone-frustum type deflector casing. The casing is concentric with the container.

Abstract: Compounds of formula I ##STR1## wherein n=1 to 5 possessing analgesic activity with reduced hepatoxicity as compared with paracetamol.

Abstract: The invention relates to a new a method for simultaneous recovering vanadium, molybdenum and gallium from alumina factory aluminate liquors. The recovering is carried out in one step by electrolyzing an alumina factory aluminate liquor a temperature exceeding 70.degree. C. with a current density of from 400 to 1200 A/m.sup.2 using a low-melting liquid alloy as a cathode and agitating said alloy mechanically.By using the new process the three precious metals can be recovered simultaneously in one step with good efficiencies without any preliminary treating of the aluminate liquor and without using any auxiliary chemical.

Abstract: New anisotropic compounds suitable for use in LC-display devices are disclosed and claimed. The new compounds are cyclohexyl cyclohexylmethyl ethers of formula (1): ##STR1## in which X and Y are respectively hydrogen, alkyl group with 1 to 12 C-atoms, alkoxy group with 1 to 12 C-atoms, monoalkylamino group with 1 to 12 C-atoms, nitrile group, nitro group, halogen, or cyclic radical of formula (1a) or (1b): ##STR2## in which R.sup.1 and R.sup.2 represent hydrogen alkyl group with 1 to 12 C-atoms, alkoxy group with 1 to 12 C-atoms, monoalkylamino group with 1 to 12 C-atoms, nitrile group, nitro group or halogen, and Z.sup.1 and Z.sup.2 represent simple covalent bonds or grounds of the formulas --COO--, --OOC--, --CH.sub.2 O-- or --OCH.sub.2, with the requirement that only one of the groups X, Y can be a cyclicradical or formula (1a) or (1b). Also disclosed and claimed are LC-mixtures containing these compounds and methods for their synthesis.

Abstract: Anisotropic compounds of the formula (1) ##STR1## wherein X and Y are each hydrogen, C.sub.1 -C.sub.12 alkyl, C.sub.1 -C.sub.12 alkoxy, N-monoalkaylamine having 1 to 12 carbon atoms in the alkyl group, halogen, cyano, nitro, or a cyclic radical of the formula ##STR2## wherein R is hydrogen, halogen, cyano, nitro, C.sub.1 -C.sub.12 alkyl, or C.sub.1 -C.sub.12 alkoxy, Z.sup.1 is a --COO-- group or a --OOC-- group and Z.sup.2 may be the same as Z.sup.1 or a single convalent bond, with the proviso that:(a) only one of the groups X and Y is a cyclic radical, and(b) neither of the groups X or Y is hydrogen, bromine, or poperidino when the other is hydrogen, have low .DELTA.n-values without a greay tendency to form smectic phases and are useful in preparing liquid crystal devices.

Abstract: The invention relates to a new method of reducing the organic substance content of alum earth production cycle performed according to the Bayer technology. By the method of the invention the majority of the organic substances present in the circulating lye can be removed easily and with only slight losses in sodium content.According to the invention one proceeds so that soda present in the hydrate wash and/or in the soda salt solution is caustified with lime, the solution is evaporated to reach a total sodium oxide concentration of 200 to 400 g/l, the precipitated solid is separated and removed from the system, and the liquid is recycled.

Abstract: A liquid crystal mixture intended for electrooptical displays having no polarizers, consisting of:a nematic liquid crystal as the host phase;an optically active additive to give the host phase a cholesteric structure; andat least one pleochroic anthraquinone dye as the guest phase dissolved in the host phase, said anthraquinone dye having the formula: ##STR1## wherein R.sup.2, R.sup.3 and R.sup.4 are the same or different substituents and are selected from the group consisting of hydrogen, hydroxyl, amino, and short-chain N-monoalkylamino substituents; Y represents halogen, alkyl or alkoxy groups each with 1-16 carbon atoms, amino, alkylamino groups with 1-16 carbon atoms in the alkyl portion, nitro, or hydroxyl group; X represents halogen, amino or the group R.sup.5, wherein R.sup.5 is an alkyl group with 1-18 carbon atoms, an alkyl chain with 1-18 carbon atoms that is interrupted with one or two oxy groups or a group having the formula:--(CH.sub.2).sub.p --(O--C.sub.2 H.sub.4).sub.r --O--R.sup.

Abstract: The invention relates to a novel process for the selective recovery of the sodium content of red mud originating from alumina plants. According to the process of the invention red mud or a slurry thereof is admixed with a ferric sulfate solution, the resulting suspension is stirred intensively for 0.5 to 1 hour at 15 to 85.degree. C, thereafter, if necessary, the pH of the suspension is adjusted to 4.4 to 4.6 and the solid substance is removed from the suspension.Using the process of the invention the sodium oxide content of red mud can be reduced to below 1.5%.