638results about "Moderator/core" patented technology

Premium synthetic lubricants comprise a synthetic isoparaffinic hydrocarbon base stock and an effective amount of at least one, and typically a plurality of lubricant additives such as a detergent, dispersant, antioxidant, antiwear additive, pout point depresant, VI improver and the like. The base stock is derived from a waxy, paraffinic, Fischer-Tropsch synthesized hydrocarbon feed fraction having an initial boiling point in the range of about 650-750° F. and continuously boiling up to at least 1050° F., by a process which comprises hydroisomerizing the feed and dewaxing the isomerate. The waxy feed has a T90-T10 temperature difference of at least 350° F. and is preferably hydroisomerized without any pretreatment, other than optional fractionation. The lubricant may also contain hydrocarbonaceous and synthetic base stock material. Lubricants, such as fully formulated multigrade automotive crankcase and transmission oils formed by adding a suitable additive package to the isoparaffinic base stock have exhibited performance superior to similar fully formulated oils based on both PAO and conventional, petroleum derived base stocks.

A molten salt breeder reactor that has fuel conduit surrounded by a fertile blanket. The fuel salt conduit has an elongated core section that allows for the generation of electrical power on a scale comparable to commercially available nuclear reactors. The geometry of the fuel conduit is such that sub-critical conditions exist near the input and output of the fuel salt conduit and the fertile blanket surrounds the input and output of the fuel salt conduit, thereby minimizing neutron losses.

Provided are an underwater processing apparatus which can effectively prevent water from entering a shield for a workpiece having a surface ruggedness, and in which variation in a gas flow for a processing part is reduced, a processing method and an application thereof to a nuclear reactor, and the under water processing device is composed of a shield means which locally cover the processing part with the gas in order to prevent water from entering the shield member, the shield means having a solid wall formed of a member which is slidable in a part where it make contact with the workpiece, and adapted to make contact with the workpiece and to be moved up and down by a pressing force, and a water jetting means for forming a water curtain around the outer periphery of the solid wall.

This invention deals with multi-component composite materials and techniques for improved shielding of neutron and gamma radiation emitting from transuranic, high-level and low-level radioactive wastes. Selective naturally occurring mineral materials are utilized to formulate, in various proportions, multi-component composite materials. Such materials are enriched with atoms that provide a substantial cumulative absorptive capacity to absorb or shield neutron and gamma radiation of variable fluxes and energies. The use of naturally occurring minerals in synergistic combination with formulated modified cement grout matrix, polymer modified asphaltene and maltene grout matrix, and polymer modified polyurethane foam grout matrix provide the radiation shielding product. These grout matrices are used as carriers for the radiation shielding composite materials and offer desired engineering and thermal attributes for various radiation management applications.

A method of forming a metal-carbon composite, the method comprising subjecting a precursor composition to a curing step followed by a carbonization step, the precursor composition comprising: (i) a phenolic component, (ii) a crosslinkable aldehyde component, (iii) a polymerization catalyst, and (iv) metal-containing particles, wherein said carbonization step comprises heating the precursor composition at a carbonizing temperature of at least 300° C. for sufficient time to convert the precursor composition to said metal-carbon composite. The produced metal-carbon composite, devices incorporating them, and methods of their use (e.g., in capacitive deionization and lithium ion batteries) are also described.

Lubricant blends and finished gear oils comprising a Fischer-Tropsch derived lubricant base oil fraction, a petroleum derived base oil, and a pour point depressant are provided. The Fischer-Tropsch derived lubricant base oil fraction comprises less than 0.30 weight percent aromatics, greater than 5 weight percent molecules with cycloparaffinic functionality, and a ratio of weight percent of molecules with monocycloparaffinic functionality to weight percent of molecules with multicycloparaffinic functionality greater than 15. The petroleum derived base oils comprises greater than 90 weight percent saturates and less than 300 ppm sulfur and is preferably selected from the group consisting of a Group II base oil, a Group III base oil, and mixtures thereof. These lubricant blends have surprising low Brookfield viscosities at −40° C.

According to the method, a reactor core is shut down during the operation cycle. One or more fuel bundles of the reactor core are then moved to new positions within the reactor core to increase a total energy, output of the reactor core as compared to continuing operation of the reactor core without the shutting down and moving steps.

The invention provides a combined square fuel assembly, a reactor core and a two-pass flowing method of a moderator and a coolant, which are suitable for a super-critical water reactor. The fuel assembly consists of 4 same child components arranged in a 2*2 square form, wherein each child component consists of multiple fuel rods arranged in a square grid form, a water rod is arranged in a central area, and a guide tube of a crossed control rod and a conduit of the water rod are placed above the component and a conduit of the water rod and a moderator duct are placed below the component; the reactor core is divided into first and second pass areas; the moderator flows into the space between the water rod and the child component from top to bottom in both passes; the coolant flows into a first pass fuel area from top to bottom; and the moderator and the coolant flow into a second pass fuel area from bottom to top after being stirred and mixed below the reactor core and flow out of the reactor core. According to the combined square fuel assembly, the reactor core and the two-pass flowing method of the super-critical water reactor, the moderator and the coolant as well as the different pass coolants in the components and the reactor core can be effectively shunted when the fuel rod is fully and uniformly moderated, the structural materials are reduced and the feasibility and safety are high.

In a nuclear reactor internal structure, generation and promotion of object-downstream separating vortices are suppressed so that coolant uniformly flows in a reactor core and pressure loss of flow of the coolant is reduced so that the flow of the coolant is stabilized. A lower connecting plate 30 arranged in a lower plenum 8 comprises a ring portion 31 in which an arcuate portion 32 and a cut-off portion are alternately formed. An outer peripheral portion of the ring portion 31 is asymmetric relative to a flow direction of main flow and also asymmetric relative to a separating flow generation direction.

A light water reactor to safely convert depleted uranium into a fuel source that could be used as a sustainable source of energy for centuries. The reactor is a type of breed-burn reactor uniquely combined with a proliferation-resistant fuel cycle with no uranium enrichment and no plutonium isolation. It is comprised of a compact factory-produced fast region and a thermal region that produces about 95% of the core power and contains the passageways for transports of delayed-neutron emitters to the fast region, where they can provide additional neutrons (source-based mode) or all the necessary excitation without an external neutron source (self-regulating mode). A second embodiment of the invention is a small unit driven by a neutron source with beam recycling for propulsion, electrical power or radioisotope production. It could also serve as a demonstration facility for the transmutation reactor with fission-fusion fuel.

The present invention relates to a fast reactor type coupling nuclear reaction implementation method and a nuclear reactor for same. The main contents comprise: a fast reactor type coupling nuclear reaction implementation method, a reactor modular design approach, a fast reactor type coupling nuclear reactor, a reactor core, a fuel element, a nuclear control system, and a proliferation fuel system. The fast reactor type coupling nuclear reactor mainly combusts thorium and nuclear waste, and has inherent security. The reactor main container is composed of a fission pool and a moderating pool that are completely isolated from each other but coupling to each other. A primary coolant is separated from a moderator. A thermal insulation layer is disposed between the fission pool and the moderating pool so that both can perform neutron exchange but heat exchange is blocked. Fast neutrons produced by the fission pool and moderated neutrons reflected by the moderating pool may enable the reactor core to simultaneously perform coupling nuclear reaction of the two types of neutrons. The moderating pool may be provided with the nuclear control system, and ex-core coupling core control may be implemented. The moderating pool is provided with a thorium purification fuel system, and on-line extraction of the purification fuel can be performed, and separation of nuclide is safe and simple, thereby providing a solution to the technical bottleneck of "thorium reactor".

The present invention is to provide a reactor core that allows a nuclear plant to continuously operate for a long term period, for example 15 years or longer, without requiring any fuel exchange, reduces the duration and number of maintenance steps involved in regular plant inspections, markedly improves plant availability and economic efficiency, and is effective in terms of nuclear nonproliferation.

A plurality of fuel assemblies 103, themselves obtained by arranging fuel rods 100 and water rods 107 in square lattices, are arranged in a square lattice at a certain pitch. The blades 102a of a cross-shaped (cruciform) control rod 102 in a cross section are inserted into four adjacent spaces formed by four fuel assemblies 100 facing each other. A value of 0.06 cm⁻¹ or greater is selected for the ratio (B/S) of the width (B) of each blade on the cruciform control rod 102 and the surface (S) of the fuel lattice defined by the surface area of a square whose side is equal to the pitch between the fuel assemblies 103.

A molten salt reactor is described that includes a containment vessel, a reactor core housed within the containment vessel, a neutron reflector spaced from the containment vessel and positioned between the core and the containment vessel, a liquid fuel comprised of a nuclear fission material dissolved in a molten salt enclosed within the core, a plurality of heat transfer pipes, each pipe having a first and a second end, wherein the first end is positioned within the reactor core for absorbing heat from the fuel, a heat exchanger external to the containment vessel for receiving the second end of each heat transfer pipe for transferring heat from the core to the heat exchanger, and at least one and preferably two or more reactor shut down systems, where at least one may be a passive system and at least one or both may be an active or a manually operated system. The liquid fuel in the core is kept within the core and heat pipes are used to carry only the heat from the liquid core to the heat exchanger.

The invention discloses a nuclear reactor core capable of improving neutron flux rate; the core is a circular structure; the center of the core is a Be thermal neutron well region, the circumference of which is a fuel component region, the circumference of which is a Be reflecting layer; the whole core is a circular structure. The maximum thermal neutron flux rate of the central Be thermal neutron well region can be over twice larger than that of the fuel region ; as the thermal neutron well region can be provided with fuel component with high uranium content, the fuel component center can form fast neutron region, therefore, the generated fission neutron has high flux rate.

Apparatus and methods according to various aspects of the present invention may operate in conjunction with composite matrix material and reinforcement material, such as nanostructures. The nanostructures may be evenly dispersed and/or aligned in the matrix material through application of an electromagnetic field, resulting in a nanocomposite material. In one embodiment, the nanocomposite material is suitable for large scale processing.

A reactor vessel includes a plenum and a reactor core with first and second sets of channels. A blanket salt flows through the first set of channels, and a fuel salt flows through the second set of channels. The plenum receives the blanket salt from the first set of channels. The blanket salt provides a breed-stock for a fission reaction in the fuel salt and transfers heat generated by the fission reaction without mixing with the fuel salt.

A photocatalytic substance having the properties of an n-type semiconductor is deposited on a surface of a metal base made of a stainless steel or Inconel. When necessary, the hydrogen concentration of the reactor water is increased. A current produced by the photocatalytic substance when the same is irradiated with light or radioactive rays in a nuclear reactor flows through the metal base to reduce corrosion current. When necessary, the photocatalytic substance is provided on its surface with at least one of Pt, Rh, Ru and Pd.

A composition of matter and method of forming a radiation shielding member at ambient temperatures in which the composition of matter includes a phosphate bonded ceramic, a radiation shielding material dispersed in the phosphate bonded ceramic matrix.

A cask includes a trunk body that includes a basket having a square pipe or a plate member forming a cell that contains a spent fuel assembly, and a neutron shield that is formed by filling a composition for neutron shielding between the trunk body and an outer cover surrounding the trunk body. The composition includes a refractory material, a density increasing agent, and a neutron shielding material composed mainly of a polymer.

In a nuclear reactor neutron panels varying in thickness in the circumferential direction are disposed at spaced circumferential locations around the reactor core so that the greatest radial thickness is at the point of highest fluence with lesser thicknesses at adjacent locations where the fluence level is lower. The neutron panels are disposed between the core barrel and the interior of the reactor vessel to maintain radiation exposure to the vessel within acceptable limits.