Abstract: Procedure for dewatering sewage sludge comprising the steps of subjecting pumpable sludge to chemical pretreatment with addition of a flocculation agent, pre-dewatering the chemically pretreated sludge by gravity filtration and conveying the pre-dewatered sludge by gravity, dewatering the pre-dewatered sludge by pressure filtration to form a sludge cake, crumbling the sludge cake to obtain sludge cake pieces, and drying the sludge cake pieces. After the dewatering step, so hard sludge cake is formed that after crumbling the sludge cake pieces are obtained which maintain their shape in accumulated consistency. A plant for the execution of the procedure is disclosed.

Abstract: A cleaning device for heat exchangers mounted on construction machines such as a bulldozer, for example, and for water pipe that can be cleaned without removing the heat exchanger or pipe from a machine, includes a cleaning water storage tank (1) connected to a pump (2) for pumping water under pressure to a heat exchanger (a) through pressure and flow regulating valves (31, 32) and a gas-liquid mixer (5) to which gas is fed from tank (6) for pulsating and producing gas bubbles in the water flow for effecting the cleaning. Flow control valves (7, 9) control the direction of flow through the heat exchanger and a strainer (8) removes the residue cleaned and carried by the water. An accumulator (4) is connected in the flow circuit with the regulating valves (31, 32) to absorb shock when the regulating valve (32) is closed and which functions together with the valves (31, 32) to produce a pulsation in the water flowing in the system.

Abstract: A teaching aid for use in explaining the biochemical and/or physiological basis of human body function in health or when suffering from a pathological condition such as diabetes mellitus. The teaching aid comprises means representing the blood stream, organs and cells and a plurality of sets of tokens representing chemical or biochemical substances. The blood stream is represented as substantially linear. The organs and cells are represented as substantially the same size and are positioned in direct communication with the blood stream representing means. The tokens are moved along the blood streams representing means and into and out of the organ and cell representing means to demonstrate the functions of the organs and cells.

Abstract: A boom support system such as those used on various hoisting equipment, such as cranes or the like, mine scaling equipment and other equipment utilizing telescopic booms. The boom support system includes a plurality of longitudinally extending support rails spaced circumferentially of the telescopic boom components with radially adjustable slides on the telescopic boom components engaged with the rails for guiding and supporting the telescopic components during their telescopic movement.

Abstract: A vertically disposed wheel chock for tandem wheels which engages the opposed tread surfaces of the tandem wheels. The wheel chock includes a pair of members which can be moved toward and away from each other and each member being wedge-shaped and including side plates with inclined edges for engagement with the opposed curved tread surface of pneumatic tires on the tandem wheels. The members are securely engaged with the tire tread surfaces above and below the rotational axes of the wheels to prevent the tandem wheels from rolling in relation to a support surface.

Abstract: An expandable and collapsible window covering is disclosed in which an unpleated facing fabric is attached to a pleated panel to provide a Roman shade type window covering. Transverse cells are formed by the attachment of the pleated panel and unpleated fabric which provide excellent insulation properties. A method for making such a shade is also disclosed.

Abstract: An apparatus for more effectively controlling the precooking operation by separating the precooking procedure into multiple distinct zones and controlling the temperature in each cooking zone. A porous conveyor belt conveys shrimp from a feeder tank at a temperature of approximately 40.degree. F. into zone 1 maintained at a temperature of 212.degree. F. and subsequently into zone 2 in which the temperature is maintained at 212.degree. F. and finally into zone 3 and optionally into zone 4 maintained at a temperature less than 212.degree. F. In zone 1 the mixture of air and steam from both above and below the shrimp will condense on the surface of the shrimp for control cooking in zone 1 in which the shrimp is heated to approximately 116.degree. F. In zone 2, the same cooking procedure raises the cooking temperature of the shrimp to approximately 173.degree. F. In zone 3, and optionally in zone 4, a controlled cooking atmosphere is maintained at 180.degree. F. to 212.degree. F.

Abstract: In connection with X-ray or like examination there is used a cassette holder arrangement which is carried by a frame structure (7) by means of pivotal arms (4) which are capable of being swung in the horizontal plane, such as to adjust the position of the cassette in the vertical direction. The arrangement enables pictures to be taken of a sitting patient in mutually perpendicular directions, with the aid of a radiation source (2). The cassette holder (3) can be swung between the exposure positions in a circuit path around the sitting patient, by activation of one of the arms (4). To this end there can be used a parallel linkage (11) which is operative to guide the cassette holder during this pivotal movement. the cassette holder is fixated relative to one of the arms (4), by means of a locking device (8), which is released when wishing to pivot the cassette holder. The invention also relates to a cassette holder arrangement of the aforedescribed kind.

Abstract: An apparatus for forming voids in concrete including baseplates secured to a wood supporting deck or form for a concrete floor by a plurality of short wood screws. An adjustable sleeve assembly is attached to each baseplate and is adjustable to a height generally equal to the thickness of the floor with the upper end of the sleeve being accessible and observable when concrete is poured. After the baseplates have been secured in place, various subsequent work procedures may be carried out without the workers encountering obstructions that would exist if upwardly projecting cavity forming members where attached to the wood deck and the sleeve assemblies are mounted prior to pouring the concrete. After the concrete has been poured and set, the sleeve assemblies and the baseplates are removed by unscrewing the sleeve assemblies, removing an upper sleeve and pulling a lower sleeve and baseplate up from the wood deck.

Abstract: An optical apparatus consisting of a laser for producing a coherent polarized beam of electromagnetic radiation of a preselected wavelength. A substrate of silicon has a first transparent cover layer for receiving the polarized beam substantially normally incident thereto, an a second transparent guide layer for receiving the polarized beam from said first layer and for supporting at least one resonant mode. The first and second layers have a preselected index of refraction and a grating is interposed between them, having a grating period less than half the preselected wavelength. The layers and grating interact to produce a standing wave resonance by Bragg reflection. A control obtains a resonance wavelength in the guide layer equal to the predetermined radiation wavelength and thereby high reflectance to modulate the polarized beam.

Abstract: A lift stool for use in conjunction with removable pot or a stationary toilet bowl is provided to assist disabled person in being lowered toward a seated position and elevated back up to a standing position and the lift stool includes elevated arms rests which may be swung upwardly to out of the way positions to enable a person to assist a more seriously disabled person in using the lift stool, a control for raising and lowering the associated toilet seat being mounted from one of the free swinging ends of the upwardly swingable arms rests and the lift stool including support wheels normally spaced slightly above a horizontal surface upon which the lift stool rests and over and onto which the lift stool may be rearwardly tilted to a position in which the raised armrests may be used as handlebars for manually rolling the lift stool over a floor surface.

Abstract: An optical pickup device used in an optomagnetic disk recording/playback apparatus, comprises a light emitting element such as a semiconductor laser for producing a light for recording information onto a recording medium and playing back the information from the medium; a parallel light generating element such as a collimator lens for changing the light from the light emitting element to a parallel light; a beam shaping element for shaping the parallel light into a substantially circular shape in cross section; a beam splitter for dividing the circular beam from the beam shaping element; a light beam receiving element for receiving a divided beam reflected on a splitting plane of the beam splitter; and a polarized plane change element such as half-wave plate provided at a predetermined position of an optical system between the light emitting element and the beam splitter, for changing a plane of polarization of light passing through by a predetermined angle.

Abstract: In order to produce high tensile strength mesh structures, starting material, which is at least 0.75 mm thick and which has a square or rectangular pattern of holes or depressions, is stretched either in one direction or in two directions at right angles. The uniaxially stretched structure has orientated strands which are connected by parallel bars, the orientation of the strands penetrating into the bars but the centers of the bars being thicker than the strands, all along the length of the bar center. The biaxially stretched structure has orientated strands which are interconnected by orientated junctions which have orientated crotches between the strands; the thinnest parts of the junctions are not less than 75% of the thickness of the strands, the thickest parts of the junctions are thicker than the thinnest parts and thicker than the strands, and the center of the junction is not the thinnest part of the junction.

Abstract: The present invention relates to compositions for protecting metals which contain a mixture constituted by stearic acid, dicyclohexylamine, and an azole derivative, and more particularly to a composition containing from 0.8 to 1.4 g/l of 1-phenyl-5-mercaptotetrazole, and from 0.005 to 0.01 g/l of the mixture stearic acid:dicyclohexylamine in the molar ratio 1:1, in solution in water, as well as to the process for its preparation, and to methods for protecting metals using said compositions.

Abstract: In towing sources of seismic energy behind a vessel, especially in connection with seismic surveys in waters which are covered with ice, the buoyancy floats and also the sources of seismic energy are readily influenced by broken up ice collecting behind the icebreaking towing vessel. In order to stabilize the tow of sources of seismic energy a towing line (7) is secured between the buoyancy means (4) belonging to the tow of sources of energy (3) and the vessel (1) at a point (10) which is located in the area of the waterline, so that towing line (7) will extend in the area of the waterline. Another towing line (8) is connected directly with the array of sources of seismic energy (5) and is secured to a towing point (11) on the vessel (1) located below the waterline. An arrangement is also disclosed for securing the towing line (8) in a suitable location to avoid influence from ice and, furthermore, the design of floats (4) avoids influence from the ice.

Abstract: Controlled ratios of ethylene to propylene are obtained in almost quantitative yields from catalytic dehydration of methanol when selected molecular sieve zeolites are used as catalysts and the methanol starting material is diluted with varying amounts of steam or inert gas.

Abstract: An on-board navigation apparatus which uses a driver having a changer function to selectively reproduce any of music- and map-containing storage media. When it becomes necessary to read map data during reproduction of a music-containing medium, the current medium is replaced with the applicable map-containing medium upon arrival of an intra-music interval. This allows one driver driving both music and map data media to read map data without interrupting the piece of music being reproduced.

Abstract: These compounds, represented by the formula (I) below, are used by way of agents inducing resistance to cryptogamic diseases in plants capable of being infested by a pathogenic fungus, for example, for the protection of wheat especially with respect to Septoria nodorum, Erysiphe graminis and Gaemannomyces graminis; of capsicum with respect to Phytophthora capsici; of melon with respect to Pseudoperonospora cubensis; of tomato with respect to Phytophthora infestans; and of "Xanthi" tobacco with respect to Phytophthora parasitica var. nicotianae.