Abstract: A baffle divides a housing into first and second compartments. The first compartment includes a chromatography oven having a fan for circulating heated air over the columns while the oven is closed and for sucking ambient temperature cooling air in the first compartment into the oven while the oven is open. Ambient air is sucked into a tortuous path in the first compartment. Cooling air from the second compartment flows into the first compartment via openings in the baffle. The cooling air flows over the oven exterior and is at least partially sucked into the oven by an oven fan while the oven is open. The oven heater, coaxial with the blades, is located between an oven wall and blades. A ring baffle, having approximately the same diameter as and coaxial with the blades, is located between the wall and the blades. A fan outside of the oven sucks air from the oven through an outlet while the oven is open.

Abstract: By the displacement chromatographic process comprising passing a solution containing a plurality of metallic elements to be separated through a column packed with activated chelating resin, passing an eluent through the column and collecting successive portions of the resultant eluate, the metallic elements can be separated into individual metallic elements not only in a high state of purity but also in a high state of concentration, with a greatly improved column efficiency.

Abstract: In the particular embodiment of the invention described in the specification, a plate pack for an inclined plate separator has plate support members forming the side walls of the separator in which the separation plates are received in grooves formed by converging tongues. The support members are releasably joined together edge to edge by a bead projecting from one edge of the support member and a groove formed in the adjacent edge of the next supporting member.

Abstract: The invention relates to an air-controlled settling apparatus having an air vessel within which is a wall that divides the vessel into air supply and air exhaust ducts. Inlet and outlet valves are mounted within the air supply duct and establishes communication between the settling chambers and the air supply and exhaust ducts. The apparatus construction is distinguished by simple construction and low noise in operation.

Abstract: In a chromatographic column assembly comprising a tubular column a first end of which is sealed, the second end of said column is also sealed in order to form an enclosure between said second end and a piston. A pressurized fluid introduced into this enclosure displaces the piston in the direction corresponding to compression of a packing or filling provided in the column. A flexible conduit ensures the circulation of a fluid to be chromatographed and crosses through the piston, the enclosure containing the pressurized fluid and the second end of the column.

Abstract: Saline-tolerant surfactant is utilized in tertiary recovery of oil. The surfactant is concentrated in a portion of the produced oil and water and is recovered by the use of a cosolvent and fresh water. Both the cosolvent and surfactant are reclaimed for reuse, while the oil is released for sale.

Abstract: A hydrotherapy return fitting is described composed of a fitting body with a waterflow passge through it that is connected to a water circulation pump. The return fitting is suitably held within an opening bored in the wall of the tub or spa and a removable decorative liner or cover of tubular shape is provided within the interior of the fitting. It has a circular peripherally extending flange which covers portions of the fitting in the interior of the tub. A manually removable screen is provided inside the decorative liner and a handle is provided on the screen so that it can be easily grasped. A suction relief valve communicates between the atmosphere and the passage through the water return fitting to permit air to enter when the return fitting is plugged breaking the suction and allowing the object to be removed.

Abstract: Apparatus for metering liquids in controlled proportions and for delivering the resultant mixture to a point of use. The disclosed apparatus is particularly suitable for use in liquid chromatography applications. In one embodiment a plurality of reservoirs each containing a liquid to be mixed are connected through respective hydraulic accumulators to a switching valve arrangement for modulating solvent composition to the inlet of a high pressure pump. A flow and composition controller sequentially activates each of the switching valves such that the non-uniformity associated with the pump draw stroke is effectively averaged over several cycles of switching valve actuation. Such averaging is accomplished by generating and maintaining a fixed relationship between switching valve cycles and pump cycles which ideally is expressed as a non-integer ratio.

Abstract: Conditioning of a sample of the cracked-gas effluent from a cracking furnace is accomplished by contacting the sample under suitable conditions with a suitable hydrocarbon absorbent in such a manner that the heavier components in the cracked-gas sample are absorbed. The rate at which the sample is contacted with the suitable hydrocarbon absorbent is controlled so as to maintain a desired composition of the conditioned sample.

Abstract: A solvent delivery system (10) has first and second pistons (92, 94) and cylinders (58, 68) connected to first and second cams (110, 112). The cams (110, 112) each have a ramped portion (150, 162) and an abrupt step (152, 164). The first cylinder (58) is connected to solenoid valves (44, 46, 48) to fill the first cylinder with solvent components during movement of cam follower (104) along ramped portion (150) of the first cam (110). Spring (140) urges the first piston (92) forward into first cylinder (58). Movement of the cam follower (104) over the step (152) of the cam (110) moves the piston (92) forward abruptly to force the solvent components from cylinder (58) into second cylinder (68). Spring (178) urges piston (94) back in cylinder (68). The second cam (112) is reversed relative to first cam (110). Movement of cam follower (106) over abrupt step (164) of second cam (112) moves second piston (94) back abruptly in cylinder (68) to receive and mix the solvent components in the cylinder (68).

Abstract: A sewage pumping station is disclosed which includes a sewage receiving wet well positioned adjacent to a machinery chamber which contains sewage pump means and associated controls. A base beam means, of hollow rectangular cross-section, is secured to the underside of the floor of the machinery chamber. The base beam means defines a suction pipe extension conduit in fluid communication with the wet well. Sewage pump means are supported above the floor of the machinery chamber by a substantially vertical suction conduit extending therebetween. The lower end of the suction conduit is in fluid communication with the suction extension conduit.A sump pump assembly is provided within the machinery chamber which directs accummulated liquid into the suction extension conduit. A control assembly is provided within the machinery chamber which senses the pressure within the suction extension conduit and controls the operation of the sewage pump means dependent upon the liquid level in the wet well.

Abstract: The present invention is concerned with a process and apparatus for generating back pressure in a liquid chromatography system, in that the eluent after having passed through the detector cell is caused to pass through a valve, said valve generating a back pressure and having for this purpose a passage (A-B) which is formed, at an interface between two bodies (20, 24), only when a sufficiently high liquid pressure has been attained, at least one of said bodies being a body of an elastic material.

Abstract: Methods of and apparatus for identifying peaks corresponding to the same chemical component in a series of liquid chromatograms to identify the peaks without foreknowledge of the chromatographic behavior of any component in the sample, or even the number of components in the sample.

Abstract: A flash chromatography apparatus and method for rapid, moderate-resolution separation of organic compounds. A solvent reservoir is pressurized with a gas, forcing solvent under pressure through tubing into and through a sorbent-packed chromatography column. More than one solvent reservoir may be provided to permit mixed-solvent elution. Alternatively, instead of pressurizing the solvent with compressed air, one or more metering pumps may be used to deliver solvent to the column. The method includes introducing a sample to be eluted into the top of a flash chromatography column, beginning elution by introducing an elution solvent under pressure into the top of the column, the elution solvent comprising a first solvent and a second solvent in a ratio from 0:1 to 1:0, modifying the elution solvent by varying the ratio of the first solvent to the second solvent, and continuing elution with the modified elution solvent.

Abstract: Thin-layer chromatography is employed to separate enantiomers of the general formula, ##STR1## in which C* represents an asymmetric center and the substituents R.sup.1, R.sup.2, and R.sup.3 are such that they supply the structural element ##STR2## for .alpha.-amino- or .alpha.-iminocarboxylic acids, particularly the well-known .alpha.-amino- or .alpha.-iminocarboxylic or for derivatives of such carboxylic acids, either of which contains no free thiol groups. In the thin-layer chromatographic separation operation a TLC plate is used which is coated with silica gel hydrophobicized by a silane derivative and which is further impregnated with an ionic compound of a divalent transition metal and a chiral selector. The mobile phase employed is a ternary mixture of a water-miscible alkanol, such as methanol, water, and acetonitrile, or a quaternary mixture of the latter ternary mixture to which a water-miscible cyclic ether, such as tetrahydrofuran, has been added.

Abstract: Electromagnetic filter making it possible to continuously discharge filtration products and a corresponding filtration process.Apart from a conventional filtration section, the filter according to the invention comprises a discharge section and preferably a washing section. A pulsation leg makes it possible to apply to the liquid column a pulsation bringing about a sudden rise of the column and then its slow fall again. Thus, the filtration products are raised and then discharged.Application to the filtration of solutions containing solid products in suspension.

Abstract: An apparatus (10) for concentrating the level of a proppant in a slurry under pressure includes a cyclone chamber (22) having a reduced diameter end with an exhaust outlet (40) therein. A slurry and proppant mixture is introduced under pressure into the chamber at an inlet (120) substantially along a path tangential to the side wall of the chamber. Flow of fluid into the cyclone chamber causes the slurry and proppant mixture to follow a spiraled path toward the exhaust outlet such that the heavier constituents in the mixture move near the inside wall of the chamber. A reflux tube (140) is positioned within the chamber and permits the removal of fluid from the low proppant concentration area of the fluid chamber and directs the fluid across a choke (90, 90') and to a deenergizer (94, 94'). The deenergizer includes a housing having an inner longitudinal tube (184) with an inlet (180) for receiving fluid from the cyclone chamber and a closed end opposite the inlet.

Abstract: A liquid filter assembly is provided including a roll filter disposed within a casing. A contaminated liquid is supplied to a space adjacent to one end face of the roll filter for passage therethrough. A filter member formed of a material such as non-woven fabric covers the end face of the roll filter where the liquid is supplied, and the filter member is in turn covered by a filter retaining disc so that the filter member is normally urged against the roll filter. The retaining disc is formed with a number of openings to pass the liquid therethrough, thus preventing the liquid pressure from being directly applied to the roll filter.

Abstract: A perturbed feedback control system for a process. Inputs to the process include a feed stream and a manipulated variable. The manipulated variable is controlled by a feedback controller. Measurements of a parameter measured "downstream" of the process are taken periodically and fed back to the controller. The feedback controller generates a control response on the basis of a comparison of the two most recent values of the downstream parameter. The comparison is made by calculating a perturbed set point which includes the values of the downstream parameter taken at the two most recent sampling periods. In a specific embodiment, the perturbed set point also includes measurements of the most recent and preceding values of the manipulated variable. A control response is applied to the manipulated variable by the feedback controller based on the value of the perturbed set point. The control system has been applied to optimize the feed rate of chemicals for sludge dewatering on a twin belt filter press.

Abstract: A liquid chromatography column assembly includes a separation column having stationary phase retaining frits is positioned within a housing adapted to accept conventional column termination fittings. The assembly includes a sealed cylindrical cavity to ensure radial distribution of the incoming fluid across the cross-section of the column.