Abstract: Cell-free enzymes are immobilized by mixing the enzymes with a starch sol or a partially gelled starch gel to form a mixture containing preferably 20 to 60% starch, gelling the mixture, extruding the gelled mixture to form strands, drying the strands and breaking the dried strands into pieces to form shaped structures having improved mechanical strength.

Abstract: A photoconductive layer is produced upon a substrate by coating the substrate with a solution in an organic solvent of a polyamic acid and of 2,4,7-trinitro-9-fluorenone (TNF) and/or 2,3,4,7-tetranitro-9-fluorenone and heating the coated substrate at a temperature not exceeding 150.degree. C. to form on the substrate a polyimide coating containing the said fluorenone compound as a photosensitizer.

Abstract: A method for automatically determining the amount of one or more substances by stripping voltammetry, said amount ranging from 10.sup.-9 to 10.sup.-5 mol/l (0.1-1000 microgrammes per liter) according to an automatically repeating programme is carried out continuously, not batch-wise, for a time span of a month or more. An apparatus implementing said method preferably comprises a hanging drop electrode and means to renew the hanging drop at the start of each determination. Pretreatment of a physical and/or chemical nature is carried through continuously outside the stripping range. (FIG. 1).

Abstract: The preparation of novel organic telluryl derivatives, which may comprise radioactive telluryl isotopes, and more particularly, of derivatives of steroids having in the CH.sub.3 -radical at position 19 a branched alkyl-Te-radical as substituent (e.g. the neopentyl-Te-group).The derivatives obtained are suitable for diagnostic purposes; the radioactively labelled ones can be used in organ scanning as well as for radio immunologic determinations in body fluids.

Abstract: The invention relates to an installation for supplying gaseous fuels such as LPG and natural gas to a combustion engine, said installation being provided with a membrane provided in a housing and being coupled to the valve stem of a gas control valve, the space of said membrane at the one side thereof being connected with a venturi, in which the gaseous fuel is mixed with air drawn into said venturi by the depression created in the engine when running, said connection being such that in said space prevails the depression created during the running of said motor, the other side of the membrane being in connection with the air inlet of the venturi, three springs being provided at said one side of the membrane, said springs being dimensioned and arranged in such a way that the first of said springs is compressed when a small depression, e.g. a pressure of 20 cm water column, occurs at said one side of the membrane, the second spring being compressed as the depression in said space increases, e.g.

Abstract: As a powerful attractant and trail-following substance for ants of the type of the Pharaoh's ant (Monomorium Pharaonis L) which is active in amounts of between 10.sup.-11 and 10.sup.-5 grams has been shown to be 2-(5'-n-Hexenyl)-5-n-pentylpyrrolidine and a few of the homologues of the 5-pentyl radical. Advantageously it can be combined with the previously proposed compound 5-methyl-3-n-butyl-octahydro-indolizine.

Abstract: A ship's maneuvering simulator comprises a wheel house of a ship having a projection screen spaced therefrom and a point light source-shadow image projector provided for the projection of a shadow image, and one or more scale models and air-water images controlled by a computer, and a projection device for the projection of a motionless part of a forepart of a ship that is visible from the wheel house. At least two plane translucent projection screens are provided that join one another at an angle, and behind each projection screen the point light source-shadow image projector is mounted such that the central position in the wheel house and the stationary point light source are positioned symmetrically with respect to this projection screen and the models provided are uniform.

Abstract: The specification relates to thin, minute foils of a synthetic material obtained by an interfacial polycondensation reaction. More specifically, a process is described in which one reactive compound is dissolved in a non-aqueous solvent that has a boiling point below the boiling point of water. A second reactive compound is dissolved in water and the non-aqueous phase is then dispersed in the aqueous phase. A polycondensation reaction takes place at the interface of the two phases resulting in the non-aqueous phase being encapsulated by the polycondensation reaction product. The dispersion of the encapsulated non-aqueous phase in the aqueous phase is then heated to a temperature above the boiling point of the non-aqueous phase, but below the boiling point of water. The heating causes the encapsulating polymer to burst and to form thin, minute polymeric foils. The foils may be used directly or after some purification treatment for the formation of a dynamic membrane.

Abstract: A mixture of cis-9-tetradecenyl acetate and cis-11-tetradecenyl acetate can be employed as a powerful attractant for instance in traps to detect or control infestations of the summerfruit Tortrix moth Adoxophyes Orana or to confuse the male insect of this species in its search for the female, thereby preventing or diminishing its reproduction.

Abstract: A hydropneumatic spring which comprises a plunger-cylinder assembly and a reservoir connected with the cylinder and which, for its level control, is provided with means for a substantially constant liquid supply and with a discharge throttling opening that varies with the position of the plunger in the cylinder. The plunger is supported in the cylinder by means of hydrostatic bearings which employ the supply and the discharge pressure of the liquid flow through the spring.