Abstract: The wet steam flow distribution section (20) of the moisture separator reheater (10) includes a multiplicity of side-by-side spaced-apart channel bars (52,54,56) extending transversely to the direction of steam flow from the distribution section to the moisture separator section (24). The bars are preferably substantially U-shaped in section, whereby the two leg portions (60,62) of each bar may be angled and slightly spaced apart from confronting leg portions of adjacent bars, thereby defining respective diffuser nozzles (64). Each nozzle has a discharge end cross-section elongated in the direction parallel to the bars, for directing wet steam toward the separator section. The spacing (Y) and other design variables associated with the bars, permit optimization and uniformity of flow over the full axial extent of the moisture separator reheater unit with minimum pressure drop across the steam distribution apparatus.

Abstract: An improved nuclear fuel assembly (10) of the type having a plurality of intersecting metal strips (14) welded at the strip intersections (32). At least some of the strips (16a, 18a) have nonlinear upper or lower edges (32a, 44a) at the intersections such that some of the intersection welds (34) at the strip upper or lower edges are at different elevations (34b) relative to intersection welds at other upper or lower edges (34a, 34c, 34d).

Abstract: A pair of regenerative burners is provided with feed means (25) for feeding a reducing agent into the products of combustion so that this agent can reduce oxides of nitrogen in the heat store to which heat is imparted by the products of combustion. Refractory elements (17,21) comprised by the heat stores may additionally or alternatively have catalytically active surfaces to promote reaction of the lower oxides of nitrogen.

Abstract: An inproved grid (16) for a nuclear fuel assembly (10), having a plurality of externally projecting, integrally formed anti-bowing springs (50) spaced about the grid perimeter plate (26), for interacting with flat surfaces (52') on the opposite grids (16') of adjacent assemblies (10'). The anti-bowing springs (50) are horizontally separated along each grid (26) in periodic alternation with substantially flat portions (52) of the perimeter plate (26). Preferably, each grid has a plurality of primary anti-bowing springs (70) that project a distance at least equal to the nominal gap (g) between assemblies, and a plurality of secondary anti-bowing springs (72) that are stiffer but project less than the primary springs. Also, backup springs (74) are disclosed as integrally formed ridges adjacent to the anti-bowing springs. The interaction of each grid (16) with its neighbor (16') "tightens" the core during power operation and provides an anti-bowing effect.

Abstract: A particle size measuring device for effecting with regard to particles present in a fluid substance the simultaneous measurement in situ of two parameters thereof; namely, particle size distribution and volumetric density. The particle size measuring device comprises a laser light source (14), a laser light conveying device (40), a collimator, a first focusing device (64), a defined sample path (74) through which particles to be measured pass, a second focusing device (78) and a detector device (82). The mode of operation of the particle size measuring device is such that the laser light from the laser light source (14) is conveyed by means of the laser light conveying device (40) to the collimator. After being collimated the laser light is transmitted to the first focusing device (64) whereby the laser light is focused and is then made to pass across the sample path (74).

Abstract: The video image of the end effector (26) and work surface (32) in the vicinity of the end effector is converted into a series of continually generated digitized images (132), which are further processed to detect and track the relative motion between the end effector and the work surface. After calibration (126), whereby an index of coordinates and arm orientation is established for a known positioning of the end effector relative to a known reference feature (28a) on the work surface, the tracking (168) of the motion of the end effector is utilized to continually update the index (104) to indicate the actual coordinate and orientation of the end effector relative to the work surface. The updated index is displayed on a live video monitor (44), and can be used as input to the feedback circuit (94) of the manipulator control system.

Abstract: A wear-reduction-shield (40) for use between the core plate (24) and lower end fitting (26) of a pressurized water reactor (10) to reduce excessive wear of in-core-instrumentation thimbles (30) due to flow induced vibrations and resist fuel assembly tipping has a cylindrical body portion 42with core plate engaging lower end surface (44). At the opposite and upper end, a tapered internal end wall (46) assists upward threading of the monitor and cable. On the outside of the upper end symmetrical leg portions (52) and central land (54) surround a thimble (30) receiving opening (48). Smoothly tapering outer surface (56) minimizes turbulence in and beyond opening (34) in lower end fitting (26). Internal dimensions of shield (40) avoid structure such as sleeve (50) which may be present.

Abstract: A process for oxidizing the sulfide (H.sub.2 S, HS.sup.-, S.sup.-2) in sour water to convert the sulfide to sulfate by producing a sulfide tolerant strain of Thiobacillus denitrificans and then co-immobilizing the T. denitrificans and CaCO.sub.3 on or within a carrier to form the biofilter. The sour water is contacted with the biofilter in a continuous process.

Abstract: A fuel element for a nuclear reactor having a zirconium tin alloy cladding tube, with a thin coating of enriched boron-containing alloy burnable poison, such as nickel-thallium-boron deposited from a reducing agent by an electroless plating process.

Abstract: Integral vanes 4 with optimized size, shape and bend angles maximize coolant mixing and fuel rod 12 heat transfer downstream. Recessed weld nuggets 5 with no vane cutout are optimized for size, strength and corrosion resistance. Staggered arches 20',22' and springs 20,22 minimize turbulence and reduce grid pressure drop and promote coolant mixing. Crowned arches 20',22' and springs 20,22 decrease scoring of fuel rods 12 and are sized to minimize turbulence and pressure drop. Minimum cutouts in unslotted section of grid strip 46,46' give 15-20% strength increase. Intermediate weld and tapered end slots 48 give 15% strength increase. Ribbed and round dimple stiffeners 38,39 on outer strips increase buckling resistance, reduce handling damage and spreads accidental loading. Outer strips 32 are optimized for strength, handling, turbulence generation and pressure drop. They also divert enough flow to interior of fuel assembly to match thermal power distribution and eliminate fuel rod corrosion concerns.

Abstract: A stabilized alpha metal matrix provides an improved ductility after irradation without loss of corrosion resistance in a "Zircaloy" alloy modified with measurable amounts of up to 0.6 percent by weight of niobium or 0.1 percent by weight of molybdenum. Tin is present in the Zircaloy in the range of 1.2 to 1.70 percent by weight and the oxygen level is in the range of from 1000 to 1600 ppm. Iron and chromium alloying element levels are those of typical Zircaloys. The average intermetallic precipitates' particle sizes are in the range of from 1200 to 1800 angstroms, thereby providing optimum corrosion resistance of the improved alloy in both boiling water and pressurized water reactors.

Abstract: Mutant strains of Thiobacillus denitrificans are used to inoculate an environment containing sulfate and sulfate-reducing bacteria to control the net formation of sulfide. The mutant strains are tolerant of significant concentrations of soluble sulfides and may also be tolerant of glutaraldehyde which is a biocide effective against sulfate-reducing bacteria and which may also be added to the environment. One environment for use of the invention is in a water injection well for the secondary production of petroleum and another is the control of sulfide production in the treatment of waste materials.

Abstract: A multiple point remote temperature sensing system includes a cable having temperature responsive segments as spaced along the length of the cable and being integral therewith. Each of the temperature responsive segments includes a temperature measuring device and a circuit which establishes a unique address for the segment whereby the local ambient temperature at each segment may be interrogated from a remote location.

Abstract: A nuclear steam generator having anti-vibration bars for limiting the motion of spaced heat exchanging tubes is provided with a shim located between every n.sup.th tube where n is greater than 1. The shims have a thickness equal to n times the dimensional difference (x-y) of the distance x between a pair of tubes and the width y of an anti-vibration bar between the tubes. The shim is of channel-shape and is put in position by cutting and removing the wrap-around bars from the outside of the tube bundle, inserting and expanding a bladder to spread the pair of tubes in the bundle on opposite sides of an anti-vibration bar, moving the anti-vibration bar between the pair of tubes to one side of the opening created by the bladder, inserting a shim of modular links between the anti-vibration bar and one tube of the pair of tubes and repeating the bladder inserting, expanding and anti-vibration bar moving steps to insert shims at intervals n along the bundle.

Abstract: A controller for an apparatus for installing a mechanical tube plug includes a controller having a controller console remote from the tube installation site and a solenoid assembly located proximate to that site. The console includes switches and indicators for providing a rotation control signal to the apparatus. The solenoid assembly includes a circuit for receiving a torque indication signal from the apparatus and an alarm circuit for setting the torque at a predetermined upper limit in response to a signal input at said controller console. The circuit operates to terminate rotation control and disable the apparatus when said limit is reached. Other features of the controller are also disclosed.

Abstract: A collecting electrode panel assembly (20) comprises a plurality of collecting electrode plates (22) disposed in successively aligned relationship beneath and suspended from an electrode support member (14) supported by the housing (12) of an electrostatic precipitator (10), such that the collecting electrode plates (22) making up the collecting electrode panel assembly (20) extend downwardly in a substantially vertical plane into the precipitation chamber (6) defined within the housing (12). Each of the plates (22) has a pair of spaced end members (24) and a central web portion (26) which extends between and interconnects the spaced end members (24). Coupling means (50) are disposed between the facing opposed end members (24) of successive plates (22) at least one location along the vertical interface of successive plates (22) to restrain bowing or warping of the assembled collecting electrode panel (20) and to keep the collecting electrode plates (22) in a common plane.

Abstract: A solid or hollow replacement rod 40 for use in a pressurized water reactor (PWR) fuel assembly 10 inserts into cells of the spacer grids 18, 20 and 22 past mixing vanes 32, without damaging them, because of its asymmetric tip 42 formed by chamfer 54 and elongated curved surface 52 and its offset "x" formed by the bowed end section 44.

Abstract: A nuclear steam supply steam generator primary nozzle 16 is sealed by a nozzle dam having segmented bulkhead portions 42 and 45 with peripheral flanges 46,50,52. A rubber diaphragm with a body 54 and peripheral strata form oppositely opening cavities 56 and 58. Hydraulic pressure from either side enters one of the cavities to create a radial sealing force against the inside surface of nozzle 16. A closed cell foam rubber sealing material 76 of 20 to 30 durometer can be interposed between the cavity defining strata and the surface 16 to improve sealing. A hinged retaining ring 70 is pinned to hold the nozzle dam against radial surface 68 machined in nozzle 16.

Abstract: There is disclosed a method for desulfurizing gases by microbiological techniques which involve the use of chemoautotrophic bacteria of the Thiobacillus genus to convert sulfides to sulfates either as a sulfide removal process or as a process for producing biomass. More specifically, the invention involves the use of Thiobacillus denitrificans under aerobic conditions to oxidize sulfur compounds such as hydrogen sulfide to sulfate compounds. The process may be carried out by various techniques such as in a continuous bioreactor system using an immobilization matrix. The method is particularly suited to the disposal of hydrogen sulfide which has been otherwise removed from natrual gas and producing a biomass byproduct.

Abstract: A manipulator for a fiberscope probe or other inspection probe includes a fixed base 20 and a chassis 96 rotating on a hollow spindle 70 relative to the base. The chassis, spindle and an internal housing 66 rotate together with a translative motor 60 for powering a friction drive and the rotation providing motor 100. The friction drive wheels 26 and 28 oppose idlers 30 and 32 which are movable by means of a tensioner 74 to increase the friction of the drive mechanism. The friction drive wheels extend into a central passage 12 through which the probe passes to drive the probe. The rotation motor acts with a gear fixed relative to base 20 and is controlled through limit switches 122 and 124 for 400.degree. of rotation. A potentiometer 130 monitors rotational positions. An encoder 140, driven by an idler to eliminate slippage, monitors the friction drive of the probe.