Abstract:
An electrically programmable memory matrix comprises a plurality of memory cells of layered amorphous or microcrystalline semiconductor repeatably switchable between high and low conductance states by voltages of alternate polarity. For each cell there is a single row line and a pair of column lines. The matrix comprises write enable means and means for maintaining voltage difference between pairs of column lines below that sufficient to write to a cell in the absence of a write-enable signal.
Abstract:
A method for separating diamonds from gangue in which a diamondiferous material-water slurry is passed through a beam of laser radiation capable of causing Raman spectral activation. The scattered radiation is detected and actuates means for separating high diamond content slurry from low diamond content slurry.
Abstract:
A method for the identification of diamonds in which a sample (3) to be identified is placed in a beam of monochromatic laser radiation (2) of pre-determined wavelength. The scattered Raman radiation emitted from the sample (3) is passed through a filter (4) adapted to pass only scattered Raman radiation of frequency characteristic of a diamond. The filtered radiation is then detected by the human eye (5) or a photocell device.
Abstract:
A product mixture containing oligomers of alkenes, ethers and optionally alcohols is prepared by the hydration and oligomerisation of the alkenes by passing the alkenes and water in a molar ratio of alkenes to water of about 3:1 to 90:1 under hydration conditions over an acid hydration catalyst, particularly a cation exchange resin. The process can be controlled so as to produce less than 0.5% by wt water in the liquid reaction product, at least 40% by wt of oligomers and less than 5% by wt of material of C12 and higher.
Abstract:
A catalyst precursor for use after reductive activation in the conversion of synthesis gas to methanol having formula: CuaThAbOx, wherein A is an alkali metal, a is from 0.1 to 4, b is from 0 to 0.5, and x is a number such that the valence requirements of the other elements for oxygen is satisfied, is prepared by the steps of (I) precipitating at a temperature below 50oC the metals copper and thorium in the form of insoluble thermally decomposable compounds thereof using a precipitant comprising a carbonate and/or bicarbonate of an alkali metal and/or ammonium, the pH being adjusted to a final value in the range from 5.0 to 7.0 (II) recovering the precipitate obtained in step (I), and (III) thermally decomposing thermally decomposable compounds comprised in the precipitate recovered in step (II), the maximum temperature utilised in the thermal decomposition being in the range from 300 to 600oC. Also a catalyst composition of formula Cua.ThO2 wherein a is from 0.1 to 4 and wherein at least 30% of the elemental copper particles are of a size less than or equal to 20 Angstroms.
Abstract:
A monohalomethane is converted to a product comprising hydrocarbons having at least 2 carbon atoms and in particular aliphatic hydrocarbons in the gasoline boiling range by contact with a synthetic crystalline gallosilicate zeolite loaded either with at least one modifying cation selected from hydrogen and metals of Groups I to VIII of the Periodic Table or with a compound of at least one Group I to VIII metal.
Abstract:
A two part impression material suitable for use as a dental impression material comprises a first part containing a product of the reaction of an alpha, beta-ethylenically unsaturated dicarboxylic acid anhydride, such as maleic anhydride, and a liquid polydiene resin, e.g. polybutadiene, and a second part containing a setting agent for the reaction product which setting agent is an alkoxylated fatty mono-amine or an alkoxylated fatty polyamine having from 2 to 30, preferably 5 to 15 moles of alkoxylate per mole of the fatty amine. The alkoxylate groups of the setting agent being one or more groups selected from the group comprising ethoxylate, propoxylate and butoxylate groups. A method of taking a dental impression using the reaction product of the first and second parts of the two part dental impression material is also disclosed.
Abstract:
Method of determining the conductance state of a non-volatile memory device switchable between high and low conductance states. The device comprises at least one p-type amorphous or microcrystalline semiconductor and an n or i-type layer. The device is irradiated with light to produce a photovoltaic response which is used to determine the conductance state.
Abstract:
A C1 to C4 monohaloalkane is converted to hydrocarbons having a greater number of carbon atoms than the monohaloalkane reactant, in particular to aliphatic hydrocarbons in the gasoline boiling range, by contacting the monohaloalkane at elevated temperature with a clay containing either hydrogen ions and/or metal cations introduced either by exchange and/or by deposition. Preferred as catalysts are the layered clays including stabilised pillared layered clays.
Abstract:
Associations of prokaryotic organisms and eukaryotic plant cells are produced by bringing bacteria and an L-form inducer into contact with the plant cell or by bringing the cell into contact with liquid obtained from plant cells containing the prokaryotic organism. Aqueous suspensions of L-form bacteria passed through a bacteria filter may be used to treat plant cells.