Abstract: A sinuous shaped heat exchanger made up of a plurality of generally U-shaped heat exchanger units or sections or banks arranged with one of the ends of each of the U-shaped banks in opposing end to end relationship with one of the ends of a next succeeding bank in such a manner that places the outlet tube sheet of such bank supporting the outlet ends of the tubes of such bank face to face with the inlet tube sheet of the next bank supporting the inlet ends of the tubes of such next succeeding bank. The tubes at the outlet side of the outlet tube sheet and the tubes at the inlet side of the inlet tube sheet protrude toward each other beyond the surfaces of the tube sheets. A removable transition connecting piece in the form of an apertured plate with the same hole diameter and pitch as the tube sheets is sandwiched between the outlet tube sheet and the inlet tube sheet. It is removably secured in that position by securing it to the aforementioned ends of the banks.

Abstract: In the polymerization under pressure of liquid olefin to polyolefin using a Ziegler type catalyst, the reaction mass, comprising a mixture of catalyst and polyolefin dissolved in liquid monomer, is mixed in a mixer with water to kill the catalyst and reaction after which the highly corrosive aqueous solution of Ziegler catalyst is separated from the monomer and dissolved polymer in a settling tank. The inner wall of the mixer and/or settling tank and/or any other part of the equipment coming into contact with the aqueous Zeigler catalyst solution is lined with an acid resistant brick lining having an intermediate membrane lining between it and the inner wall. A carbon filled furan resin is used as a mortar for the brick lining and the membrane is a fiber glass reinforced furan resin to which the brick lining is cemented by a carbon filled furan resin adhesive. The membrane is also cemented to the inner wall by a carbon filled furan resin adhesive.

Abstract: A mixing valve comprising a rigid structure containing an interior recess and inlet and discharge ports in communication therewith, and weir plates and a slide plate confined in the recess for movement of the weir plates transversely of the recess with respect to the ports and for movement of the slide plate longitudinally of the recess with respect to the ports, said weir plates and slide plate containing openings which in predetermined positions of the plates are aligned in exact registration with the ports, and which can be moved relative to each other and to the ports to vary both the ratio of the fluids to be mixed to each other and the total flow of the fluids through the mixing valve.

Abstract: In the polymerization under pressure of liquid olefin to polyolefin using a Ziegler type catalyst in which the reaction mass, comprising a mixture of catalyst and polyolefin dissolved in liquid monomer, is mixed in a mixer with water to kill the catalyst and reaction after which the highly corrosive aqueous solution of Ziegler catalyst is separated from the monomer and dissolved polymer in a settling tank; lining the inner wall of the mixer and/or settling tank and/or any other part of the equipment coming into contact with the aqueous Ziegler catalyst solution with an acid resistant brick lining having an intermediate membrane lining between it and such inner wall and in which the mortar of the brick lining is a carbon-filled furan polymer, in which the membrane is a fiber glass reinforced furan polymer and in which the brick lining is cemented to the membrane and the membrane is cemented to the inner wall by a carbon-filled furan polymer adhesive.

Abstract: Novel folic acid derivatives useful in processes for analysis of biological fluids for folic acid or its metabolites comprising components of the formula: ##STR1## wherein R is hydrogen or radioactive iodine.

Abstract: Keyboard device having a top flexible plastic contactor sheet with a first circuit pattern thereon, said first pattern comprising contactors and circuit lines, a bottom sheet having a second circuit pattern comprising contacts and circuit lines, an insulator spacer having openings in register with said contactors, said sheet having formed therein one or a plurality of protrusions or domes which support a portion of the first circuit pattern, and means for continuously urging the one or plurality of protrusions or domes supporting a portion of said first circuit pattern against a portion of said second circuit pattern.

Abstract: A multi-terminal connector element comprising a stack of alternately arranged conductor grids and spacer grids containing spaced parallel lines of spaced openings which collectively define spaced parallel passages, the axes of which are perpendicular to the planes of the grids, spaced parallel conductors on the opposite faces of the conductor grids continuously extending from edge to edge along the openings with portions extending into the openings, said conductor grids being arranged so that the conductors in adjacent conductor grids are at right angles to each other, wiper bearing elements adapted to be inserted into the passages, mounting wipers which extend radially therefrom and axially spaced therealong a distance corresponding to the distance between conductor grids, said wiper carrying elements being rotatable to move the wipers into engagement with the inwardly extending portions of the conductor elements and conductor elements within the wiper bearing elements connecting the wipers.

Abstract: Liquid scintillation counting compositions which include certain polyethoxylated poly(oxypropylene) emulsifiers allow stable dispersion of aqueous or other samples merely by shaking. Preferred are mixtures of such emulsifiers, which give homogeneous, monophasic-appearing dispersions over wide ranges of temperature and aqueous sample content. Certain of these emulsifiers, without being mixed, are of particular advantage when used in analysis of samples obtained through radioimmunoassay techniques, which are extremely difficult to disperse. Certain of these emulsifiers, also without being mixed, uniformly give homogeneous, monophasic appearing aqueous counting samples over much wider ranges of aqueous sample content and temperature than prior sample emulsifiers.

Abstract: A circuit board or sheet of homogeneous material having one or more circuit elements adhering to a surface thereof, said sheet providing a low through resistance path between each circuit element and opposed and aligned contacts positioned in surface contact with the opposite side of the sheet while providing a high isolation resistance between out of alignment contacts positioned on the opposite side of the sheet and between contacts positioned on the same side of the sheet positioned an isolation distance from said circuit elements. The circuit board with a circuit pattern is shown in various applications, such as keyboard or watch.

Abstract: A tracer comprising a polymer coated ion exchange core either labelled with nuclide, stable or radioactive or unlabelled and finding particular utility in circulatory determinations in animals or in the chemical process industries to detect or measure fluid flow.

Abstract: An air pollution control device for controlling the velocity of discharge from an industrial chimney or smokestack in order to optimize the plume rise and thereby minimize air pollution comprising a variable pitch truncated cone adapted to be mounted at or near the top of the chimney or stack, said cone being constructed to be expandable and contractible with respect to the axis of the chimney or associated flue or flues and kinematic means manually or automatically operable to control the size of the flow path of the gases through the truncated cone.

Abstract: Keyboards having flexible plastic domes which snap when depressed to provide tactile feel, at least some of said domes formed from a sheet of plastic and having a bar shaped concave snap initiator formed in said dome, and an actuator comprising at least one cross bar for engaging the snap initiator to initiate dome depression in situations in which the actuator used to depress the dome does not effectively produce snapping of the conventional dome because of the shape of the actuator.

Abstract: An improved solid-phase radioimmunological assay method for assay of an antigen in a biological fluid, e.g., blood plasma, by use of a solid phase polymeric substrate on which is adsorbed in solid phase an antibody composite layer, comprising a solid phase precoat of an anti-antibody (Ab.sup.2) (i.e., an antibody to an animal blood serum and sometimes referred to as a second antibody) bound to said substrate and a solid phase antibody Ab specific to said antigen (sometimes referred to as a primary antibody) immunologically bound to said anti-antibody precoat.

Abstract: Apparatus and method for improving the efficiency of combustion, particularly in internal combustion engines, are disclosed. Air is circulated at a substantially constant, controlled rate from a blower or compressor through a control valve to a plurality of release points beneath a catalyzing or catalyst-forming liquid, such as water, and is released in such a manner as to ensure the slow growth of relatively large bubbles. These bubbles break at the liquid surface, and the catalyst-laden air is then returned to the gas impelling means, e.g. blower or compressor, in which it is mixed with more air and returned to the system. A portion of the catalyst-laden air is directed to the combustion device, e.g. the carburetor or intake manifold of an internal combustion engine, the remainder being returned to contact with the catalyzing or catalyst-forming liquid.

Abstract: Cooling the highly viscous reaction mass during catalytic polymerization of liquid olefins to polyolefins by pumping it to and from the reactor through the tubes of a heat transfer single pass cooler rather than a heat transfer multi-pass cooler as has been done in the past, increasing the number of the tubes in the single pass cooler as compared to the multi-pass cooler, reducing the diameter of the tubes and increasing the pump capacity. The number of tubes and pump capacity are increased sufficiently and the internal diameters of the tubes are decreased sufficiently so that the heat transfer coefficient of the single pass cooler is between 10 and 20 BTU/ft.sup.2 hr. .degree. F.

Abstract: A flowable abrasive composition comprising a polyboronorgano silicon compound and dispersed abrasive granules, said composition being modified with a gel formed from a metallic soap (8-22 carbon atoms) and a hydrocarbon oil. The composition is especially useful for honing, abrading, deburring or polishing surfaces, especially metallic surfaces.

Abstract: A technetium-99m-stannous-phosphate complex in which the phosphate moiety includes pyrophosphate and in which no more than 5 to 15% or 20% by weight of such phosphate moiety is a linear polyphosphate of molecular weight greater than pyrophosphate, a method of making the same, a method of using the same by in vivo intravenous administration to a mammal of the sterile, nonpyrogenic complex followed by radioassay scanning or imaging the skeletal structure, and a kit made up of a stannous-phosphate complex in which the phosphate moiety is pyrophosphate and in which no more than 5 to 15% or 20% by weight of such phosphate moiety is a linear polyphosphate of molecular weight greater than pyrophosphate.