摘要:
Arsenic acid is formed from arsenous acid and water under oxygen pressure with catalytic amounts of nitric acid and a halide whereby the nitric oxide by-product is regenerated to nitric acid for contact with fresh arsenous acid.
摘要:
Wooden beams containing concealed load distribution means embedded therein are disclosed herein. The wooden beams may be either laminated or unitary. The load distribution means is comprised of an elongated member suitably adapted such that loads exerted on the elongated member are therefrom transmitted to and more evenly distributed within the wooden beam.
摘要:
Articles and a method are disclosed useful for providing a lift insert for a cast concrete product, such as a cast concrete slab or panel. The articles include a threadless plug for temporary insertion into an insert for receiving a lifting device in a cast concrete product, an insertion tool therefor, and the insert assembly. The threadless plug is characterized by an elastomeric tubular member having closure and/or abutment means on each end and dimensioned such that, in its operative position in the lift insert, such as a coil insert, the portion of the tubular member between the ends is placed in tension to positively seal against ingress of concrete into the top of the coil or insert and between the void plug and the coil during casting. The tool and method involve laterally inserting a flattened and then folded lower portion of the threadless tubular plug into a tubular tool member, longitudinally inserting the plug and tool member into the top of a cylindrical lift insert, longitudinally stretching the plug by frictional engagement with the tubular tool member and contemporaneous engagement of the upper abutment means with the lift insert, while withdrawing the tool member from the insert, and compressively affixing the lower abutment means in overlying intimate contact with the lower end of the insert upon total withdrawal so as to place the intermediate portion of the plug between the abutment means in tension.
摘要:
A ternary alloy comprised of cerium, nickel and manganese is characterized in having CaCu.sub.5 hexagonal crystal structure and stoichiometry. Members of a preferred class of compounds, represented by the empirical formula CeNi.sub.5-x Mn.sub.x wherein "x" has a value between 0.1 and about 1.0. These alloys react with hydrogen readily and can absorb a large amount of hydrogen at moderate pressure and temperature and are particularly suitable for use as hydrogen storage materials.
摘要:
A group of phenolic phosphite compounds having the formula ##STR1## wherein R and R' may be the same or different and are tertiary alkyl groups containing from 4 to 12 carbon atoms. These compounds are disclosed to be useful as stabilizers and antioxidants in various organic materials.
摘要:
A method of protecting organic materials from fungi and/or bacteria is provided which comprises applying to said organic material a minor but effective biocidal amount of a compound of the formula: ##STR1## wherein M is selected from H,P and an alkali metal or alkali earth metal and n is an integer selected from 1 to 3.
摘要:
A rotary vane valve having a cylindrical housing with a pair of opposed end bells and an interior axial shaft. A pair of spaced shroud structures are fixed to the shaft at the ends of the vanes to generally separate the interior of the cylindrical housing from the end bells. These shroud structures are spaced from the cylindrical housing at their outer peripheral edges, but an annular throttle plate is spaced axially outwardly at a close distance from these shrouds and adjacent at its outer edge to the cylindrical housing to increase the velocity of purge gas flowing inwardly between the cylindrical housing and the outer peripheral edge of the shroud so that the escape of gas from the interior of the cylindrical housing is effectively prevented. The inner lateral surface of the annular throttle plate is divided into a low pressure zone adjacent the inlet opening and a high pressure zone adjacent the outlet opening in situations where the inlet opening is at a lower pressure than the outlet opening. The low pressure zone is roughened or has a plurality of radially spaced, concentric arcuate grooves while the high pressure zone is recessed with the result that frictional resistance to the flow of purge gas will be greater in the low pressure zone than in the high pressure zone so that the flow of purge gas will tend to be uniformly distributed at all points along the periphery of the throttle plate.
摘要:
A process is disclosed for separating nitrated phenolic compounds from other nitrated and unnitrated phenolics by treating a mixture of the phenolics with a metal halide salt. The metal halide salt preferentially forms a complex with one of the phenolics over other related phenolics in the mixture. The preferentially-formed complex of one of the phenolics may then be isolated from the mixture and the complex decomposed to provide a product substantially enriched in, or substantially entirely composed of, one phenolic. The process is particularly suitable for resolving a mixture comprising phenol or cresol from their ortho-nitrated derivatives, or a mixture of two isomeric nitrated phenols or cresols or a mixture of mono- and dinitrated phenols or cresols.
摘要:
An apparatus and method for applying a multi-component liquid adhesive. A liquid resin reservoir and a liquid hardener reservoir are connected by separate conduit means to resin and hardener mix chamber which is positioned adjacent to a dispenser so that the adhesive can be spread at substantially the same time as it is mixed. Separate resin and hardener pumps are each driven by their own variable output capacity power sources and means are provided for sensing the instantaneous speed of these pumps. These sensors are connected to separate control means for the power sources so that the power output to both of the pumps will be proportional to their respective instantaneous speeds. This apparatus compensates for temperature induced changes in viscosity of the resin or hardener so as to allow mixing proportions to remain constant. Also disclosed is a means for increasing or decreasing the total amount of adhesive produced without having to reset the resin and hardener mix and a means for forcing water or air into the mix chamber in the event of an unanticipated stoppage of the system so as to prevent hardening of the mixture in the mix chamber and dispenser.
摘要:
The invention discloses a method of impregnating a porous catalyst carrier with a partially hydrolyzed aqueous methanol solution of titanium tetrachloride, and completing the hydrolysis to titanium dioxide under controlled conditions of temperature and by-product removal to obtain the desired anatase, rutile or combination anatase/rutile polymorphic form of titanium dioxide.