Abstract:
Le conteneur se compose d'une paroi latérale (2) dont les bordures d'extrémité (3, 4) sont chacune pourvues d'un élément d'obturation (5, 6), dont l'un au moins est rapporté pour fermer une ouverture. Le contour périphérique (6c) de l'élément d'obturation rapporté (6) et le contour intérieur (4a) de la bordure d'extrémité (4) associée de la paroi latérale (2) sont de formes générales complémentaires sur au moins une partie de leurs hauteurs respectives, de sorte que ledit élément d'obturation rapporté (6) vienne se loger sur au moins une partie de sa hauteur dans l'encombrement délimité par ladite bordure d'extrémité (4) de la paroi latérale (2) et vienne s'appuyer sur ladite bordure d'extrémité (4) par des ajustements d'ergots (11) dans des logements (10) de forme complémentaire. Les surfaces d'emboîtement inclinées font un angle de 20° à 40° avec l'axe du conteneur.
Abstract:
Disclosed is reflector graphite which is characterized in that the main component of the graphite is nuclear-purity natural graphite in addition to silicon carbide and/or zirconium carbide, the pressed pieces are shaped by a combined cold-hot pressing process, and the thermal treatment of the pressed pieces is limited to temperatures of less than 2000°C.
Abstract:
The invention relates to a recombiner element (4) comprising a plurality of catalyst elements (8) that are arranged in a common housing (6) and that trigger a recombination reaction with oxygen when hydrogen is carried along in a feed gas flow, the housing (6) surrounding the catalyst elements (8), which are arranged therein, in a funnel-type way in such a manner that the heat released by the recombination reaction supports the gas flow inside the housing (6) by a convection effect, which recombiner element safeguards a reliable removal of the hydrogen from the gas mixture with an especially high degree of operational safety even under comparatively extreme conditions or scenarios of said type. According to the invention, at least one of the catalyst elements (8) arranged inside the housing (6) has a predetermined ignition zone (20) in which a surface temperature of more than 560°C is produced in the convective operation at ambient conditions of approximately 1 bar and 100°C at a hydrogen concentration in the feed gas flow of more than 5% by volume.
Abstract:
Reflektorgraphit, dadurch gekennzeichnet, dass die Hauptkomponente des Graphits aus dem nuklearreinen Naturgraphit, sowie Siliziumcarbid und/oder Zirconcarbid besteht, die Formgebung der Preßlinge durch das kombinierte Kalt-Warm-Pressen erfolgt und die Wärmebehandlung der Preßlinge auf Temperaturen von weniger als 2000°C begrenzt ist.
Abstract:
A system (7) for evacuating the residual heat from a nuclear reactor (1) cooled with liquid metal or molten salts has two types of heat exchangers (8) immersed in the primary fluid (5) of the reactor (1) : heat exchangers (8a) with higher power density, which use boiling water as secondary cooling fluid (9) and are particularly suitable for evacuating the residual heat in the first days after turning-off of the reactor; and heat exchangers (8b) operating with atmospheric air or with water and suitable for evacuating the residual heat for indefinite periods of time. Both types of heat exchangers present a bundle of heat -exchange elements (35), shaped in such a way that the secondary fluid (9) circulating in each element (35) is separated from the primary fluid (5) of the reactor (1) by a double wall (40, 41) of the element (35), which delimits a gap (42) introduced in which is a pressurized inert gas having the function of continuous monitoring of the integrity of the heat exchanger (8) and of thermal resistance calibrated for preventing solidification of the primary fluid (5) of the reactor (1) in the heat exchanger (8).
Abstract:
The invention in particular relates to a transport shoe for sintering nuclear fuel pellets comprising a base and at least one opening (18), wherein said base is provided with substantially flat thrust (6) and rest (8) faces. The shoe is advantageously made of a lanthanum oxide-containing molybdenum alloy. A method for producing the inventive shoe and a sintering method using at least one said shoe are also disclosed.
Abstract:
A radio-pharmaceutical pig (900) for transporting a syringe containing a radio-pharmaceutical includes a first cylindrical member (910) having a first tungsten body (912) defining a first cavity (916) therein. A second cylindrical member (930) has a second tungsten body (932) defining a second cavity (936) therethrough and is capable of engagement with the first cylindrical member (910) so that the first cavity (916) is in substantial alignment with the second cavity (936). A third cylindrical member (950) includes a third tungsten body (952) defining a third cavity (956) and is capable of engagement with the second cylindrical member (930) so that the third cavity (956) is in substantial alignment with the second cavity (936). The first cavity (916), the second cavity (936) and the third cavity (956) are shaped so as to be complimentary in shape of the syringe (10).
Abstract:
This invention relates to a method of preparing nuclear fuel including the step of depositing at least two adjacent series of layers (16, 18) around a kernel (12) of fissile material, each series comprising a layer of pyrolytic carbon (16) contiguous with a layer of silicon carbide (18) and each layer (16, 18) having a thickness of at most (10) micrometres, such that alternate layers of (16, 18) of pyrolytic carbon and silicon carbide are deposited around the kernel (12). The invention extends to a nuclear fuel element (10).
Abstract:
An improved nuclear shielding material that is flexible so as to effectively fill voids in radiation containment structures. Under very high temperatures the material is designed to undergo pyrolysis and transform into a strong ceramic material. The material contains a number of components, the first of which is a polymeric elastomer matrix such as two part self-polymerizing system like RTF silicone rubber. Additional components include: a compound to shield gamma radiation like tungsten carbide powder, a neutron absorbing/gamma blocking compound such as boron carbide powder, a heat conducting material such as diamond powder, a high temperature resistant compond such as silicon dioxide powder, a second neutron absorbing compound which also imparts electrical conductivity, namely barium sulfate powder, and a hydrogen gas surpassing component which readily absorbs hydrogen such as sponge palladium.