Abstract: There is provided an electrode adapted for the selective electrocatalytic hydrogenation of nitro groups to amino groups comprising a thin grid coated with a thin layer of nickel, the latter being itself coated with a further layer of nickel in which are dispersed or embedded fine particles of Devarda copper or Raney copper.

Abstract: The disclosure herein describes a method and apparatus for the removal, by dialysis, of gases physically dissolved in the blood of a person, more particularly a diver or an aviator; the blood is brought into contact, in an exchange cell, with a membrane permeable to gases only; a liquid having high solubility for gases is circulated on the side of the membrane so that the gases dissolved in the blood are made to follow their chemical potential gradient across the membrane into the liquid.

Abstract: The disclosure herein describes a furnace for consuming solid fuel, such as wood, which comprises a gravitational feed chute for feeding the solid fuel in a combustion chamber; the chute has an open lower feed end adjoining the combustion chamber, the feed end being equipped with a plurality of flexible spaced retaining elements which serve to support the load of solid fuel in the chute; air nozzles are provided in the combustion chamber facing the feed end of the chute to create a circulation forcing combustion gases to pass through a zone of high temperature in the combustion chamber.

Abstract: The invention relates to a mass spectrometry method for determining the absolute value of a given isotopic ratio of an unknown sample and/or the difference of isotope content between an unknown sample and a reference, which comprises (a) obtaining with or without chemical reaction a substrate capable of providing a fragmentation characteristic of the presence or absence of a specified isotope and usable to retrace the parent ions by the metastable ions technique consisting of accelerating voltage scan, (b) introducing said substrate into the source of a mass spectrometer followed by the ionization of said substrate, (c) retracing with metastable ions technique the parent ions of a daughter ion resulting from the loss of a neutral fragment characteristic of the presence or absence of the specified isotope in the substrate, (d) comparing the relative intensities, as expressed by peak areas or heights, of the metastable transitions between, first, said daughter ion and the substrate parent ion, and second, said

Abstract: Bit rate in a PCM Companding system is reduced by transmitting sample magnitude (X.sub.n) if the sample is near a zero-crossing, and transmitting the difference (D.sub.n) between sequential samples if not near a zero-crossing. ROMs are used for mapping (transforming) full versus reduced data.

Abstract: There is provided a process for agglomerating volatilized silica in the form of grains by wetting same with from about 10 to about 35% by weight of an alkali or alkaline earth metal oxide solution in water, said agglomerated volatilized silica having a densification factor of 1.7 to 2.5 (when oven-dried) and a dry bulk density of from about 500 to 775 kg/m.sup.3. These agglomerated volatilized silica grains can be used to replace advantageously up to 50%, and in some cases more, by weight of Portland cement in the manufacture of concrete.

Abstract: There is disclosed a process for preparing ultra pure silicon from metallurgical grade silicon, which comprises (a) continuously passing powdered and acid-leached metallurgical grade silicon through an induction plasma; (b) quenching said treated particles whereby upon solidification of the molten particles, a portion of the impurities therein migrates to the surface of the granules obtained; (c) acid-leaching the surface impurities of the granules obtained in step (b); and (d) after drying the granules obtained, repeating steps (a), (b) and (c) until a silicon of the desired purity is obtained.

Abstract: There is disclosed a compacted unit of metallurgical grade granular material selected from silicon and ferrosilicon comprising a compressed homogeneous mixture of a fine powder of a silicon material selected from the group consisting of silicon and ferrosilicon, said silicon material being finer than 160 .mu.m, from 2 to about 5% by weight of the silicon material of sodium or calcium bentonite and from 2 to about 5% by weight of the silicon material of sodium or calcium lignosulfonate. The novel compacted units are useful for use in industrial processes requiring substantially pure silicon or ferrosilicon.

Abstract: There is provided a process for the hydrogenolysis of raw humid peat by treating untreated peat as obtained from the bog with carbon monoxide at a temperature of from 350.degree. to 373.degree. C. and under a pressure up to 35 MPa and recovering bitumen-like compounds from the non-aqueous phase.

Abstract: There is provided a process for removing pollutant particulates from a contaminated gas which comprises:(a) passing a stream of gas containing pollutant particulates through a liquid film absorbed on a continuously circulating filter supported by a perforated carrier matrix wherein part of said filter is continuously passing through a liquid reservoir containing said filtering liquid selected from liquid fluorocarbons and liquid silicones whereby the contaminant particulates carried by said gas are absorbed by said liquid film acting as a filter barrier for said particulates, and(b) recovering the gas after its passage through said liquid film barrier filter, said gas being free of said particulates. There is also disclosed an apparatus for carrying out the process. The apparatus can be positioned in a face mask.

Abstract: The addition of an excess of asbestos tailings in the course of the extraction of magnesium from asbestos tailings by digestion with an acid greatly facilitates the elimination of silica and other impurities by filtration of the resulting reaction mixture. The improvement reduces the filtration time and the filtration leaves a cake which is much easier to dispose.

Abstract: There is provided a novel harzburgite of the formula Py.sub.x Ol.sub.(1-x) where x is a decimal number of from 0.001 to 0.4, Py is an abbreviation for pyroxene, and Ol is an abbreviation for olivine having a total iron oxide content of less than 5% which is obtained by calcining a demagnetized fraction from a magnetite-containing serpentinite. The novel harzburgite is useful for preparing refractories.

Abstract: Substantially pure magnesium hydroxide or carbonate is obtained from naturally-occurring minerals containing at least 10% magnesium silicate by adjusting the pH a magnesium bisulfite solution obtained therefrom to between 8.0 and 8.9 under an oxidizing atmosphere thereby to produce a magnesium sulfate solution from which the magnesium hydroxide or carbonate can be readily obtained.

Abstract: There is provided a novel process for preparing a carbon supported metal catalyst which comprises impregnating a peat material selected from finely divided peat, ammoniated peat and humic materials derived from peat with an aqueous solution of a metallic salt, drying the impregnated peat and pyrolyzing same in an inert atmosphere to yield a carbon supported metal and/or metal oxide.

Abstract: The disclosure herein describes a method and a system for speech detection on PCM multiplexed voice channels; for each channel, a decision is reached every M samples regarding the channel activity; in addition, the nature of speech is detected as: voiced (compact or non-compact) or unvoiced (fricative or non-fricative) when the channel is active; pure silence, white noise or echo when the channel is inactive. The decision is based on the joint value of the amplitude, zero crossing of the signal and zero crossing of the signal derivative.

Abstract: The disclosure herein describes a carrier adapted to receive observation and/or manipulation instruments; the carrier consists of a train of articulated segments whose angular displacement is controlled by a series of magnetic clutches; the leading segment is guided from the carrier's proximal end, and the guide angle is repeated automatically at the articulations of all following segments; a central channel in each segment accepts instruments for observation and manipulation. One advantageous application of the present carrier is its use as an endoscope for inspecting a hollow portion in a living body.

Abstract: The invention relates to a digital converter and to a method for digitally converting a coded signal being at a delta rate into another coded signal flowing at a PCM rate. First, the code of the delta signal is converted into an intermediate code, this intermediate code being at a rate corresponding to the delta rate. Then, the rate of the intermediate coded signal is converted into the rate of the PCM signal. And, finally, the code of the intermediate signal is changed into the code of the PCM signal.

Abstract: A lightweight aggregate suitable for use in the manufacture of lightweight concrete, the lightweight aggregate being in the shape of hollow spheres, the outer surface of which is substantially rough and the inner surface of which is substantially vitrified, the wall being made of fired mineral or ceramic powder, the thickness of the wall being from 0.045 to 0.30 of an inch, the sphere being characterized by an outer diameter of 1/8 to 1 1/2 inches and a saturated surface dried specific gravity of from 1.4 to 1.65.