There are disclosed herein equipment and methods for screening and concentrating wastewater overflow from combined sewer systems. Exemplary equipment includes a separator employing a substantially cylindrical rotating screen. Influent is piped upwardly into the equipment and deflected outwardly toward the inner surface of the screen in a manner to achieve a desired flow rate and flow pattern of the influent onto the screen. Means are provided for controlling the flow rate and for suitably direct...

Method for determining the sulfate ion concentration of an aqueous solution. The mechanism of the method resides in the use of a chelate of a metal which under acidic conditions dissociates to release metal ions which will react with the sulfate ion present to produce a colloidal metal sulfate precipitate. In order to ensure that the free chelant does not precipitate or react to form a precipitate, there is also added to the solution a quantity of a metal compound, the metal of which will replac...

An apparatus adapted for use in an electrographic magnetic brush development station for maintaining the concentration of toner in the developer mixture at a substantially constant level. Toner concentration is monitored by sampling the self-biasing potential generated by the brush as it periodically contacts uncharged areas of the electrographic recording element. Such potential has been found to be inversely proportional to the concentration of toner in the developer mixture.

A method of concentrating and recovering spodumene from an aqueous pulp or slurry by conditioning the pulp with an aliphatic primary beta-amine having from seven to 15 carbon atoms (preferably as a soluble acid salt), subjecting to flotation at a pH of about 8-10 to float off the impurities, and recovering the spodumene concentrate as residue.

A rotating dial-type indicator for illustrating the approximate theoretical alcoholic concentration in the blood of an average man as related to the volume of alcohol consumed, weight of the individual, and time elapsed. The indicator includes at least two circular scales, one being rotatable with respect to the other; one of the scales representing time, the other representing alcoholic concentration in the blood. A limit means is provided for discreetly rotating one of the scales throughout a ...

Aqueous solutions containing up to about 25 percent by weight of acrylamide are concentrated to a maximum concentration of about 30 percent by cooling the less concentrated solutions to produce a mush of ice crystals and separating the ice from the mother liquor. Adiabatic cooling under reduced pressure is preferred.

An apparatus for measuring a methanol concentration is provided. The apparatus is located in a pipe which supplies liquid fuel to the anode of a direct liquid feed fuel cell, and may include a vertical supporting beam located in the pipe; a horizontal plate located on the supporting beam and having an upper surface with a predetermined roughness; and a sensor fixed to a side of the supporting beam, which generates an electrical signal through a transformation of the supporting beam resulting fro...

The present invention relates to a gravity/flotation circuit where a mineral stream, such as a flotation rougher or cleaner concentrate, undergoes a two stage size separation wherein: i) the screen of the first stage provides a coarse stream of particles greater than 110 microns and a fines stream of particles less than 110 microns; and ii) the fines stream of less than 110 microns is subjected to the second stage separation whereupon a cyclone provides an ultrafine/slimes stream of p80 less tha...

An oxygen sensor is employed for determining whether the exhaust air-fuel ratio is rich or lean. A voltage is applied to the oxygen sensor at device impedance calculation intervals to calculate device impedance. After device impedance calculation, a reverse voltage is applied to the oxygen sensor with a view toward promptly negating the influence of voltage application on the sensor output. Subsequently, the sensor output of the oxygen sensor is sampled at sampling time intervals until it is con...

A topical insecticide is provided which can be safe to use and avoids many common deleterious side effects of conventional topical insecticides. In one preferred embodiment of the invention, the active ingredient of the insecticide formulation is an amine derivative, having a nitro-methylene group, a nitroamino group or a cyanoamino group, which can be formulated to have low toxicity and excellent insecticidal activity. One particularly suitable insecticide is 1-{(tetrahydro-3-furanyl)methyl}-2-...