摘要:
A self-supporting inorganic and radiation-hard neutron shielding panel for use in absorbing thermal neutrons. The panel is constructed substantially of concrete and includes a high level of boron by weight to enhance the absorption of thermal neutrons. A layer of radiation-resistant fiber reinforcement within the panel enables production of a thin, strong panel that is self-supporting and easily transportable. Mounting means are included on the panel to facilitate easy mounting on a wall or similar surface. The panels are constructed entirely of inorganic materials and include at least 58% boron by weight to maximize their effectiveness in shielding against thermal neutrons. Further disclosed are methods for forming the neutron-shielding panels.
摘要:
Using crystalline silica, mixed with cement powder, to reduce the heating of the cement paste caused by the hydration of said powder, during a process of packaging of radioactive waste, a formulation for the packaging of radioactive waste by cementing, which comprises such silica, a method for packaging radioactive waste implementing this formulation, and a package for packaging of radioactive waste which is obtained by this method.
摘要:
The invention relates to a method for electrokinetic decontamination of a porous solid medium, which comprises: a) extracting the contaminating species present in the solid medium in an electrolyte appearing as an essentially inorganic gel, this extraction being obtained by applying an electric current between two electrodes positioned at the surface and/or in the interior of the solid medium, the contact of at least one of these electrodes with said solid medium being ensured by a layer of said gel, b) drying the gel containing the thereby extracted contaminating species until a dry residue is obtained which fractures, and c) removing the thereby obtained dry residue from said solid residue. Applications: decontamination of materials with a cement matrix, notably within the scope of dismantlement of military or industrial installations, in particular nuclear installations, or the rehabilitation of installations likely to have been contaminated by ecotoxic or radiological chemical species; clearing pollution of geological soils, sediments and sludges.
摘要:
Electrically gradated carbon foam materials that have changing or differing electrical properties through the thickness of the carbon foam material and methods for making these electrically gradated carbon foam materials are described herein. In some embodiments, the electrically gradated carbon foam materials exhibit increasing electrical resistivity through the thickness of the carbon foam material such that the electrical resistivity near a second surface of the carbon foam is at least 2 times greater than the electrical resistivity near a first surface of the carbon foam. These electrically gradated carbon foam materials may be used as radar absorbers, as well as in electromagnetic interference (EMI) shielding schemes.
摘要:
A construction composition includes: an ash in an amount of 90.0-99.9 wt. %, based on the total weight of the construction composition, wherein the ash is fly ash or bottom ash; an additive composition in an amount of 0.1-10.0 wt. %, based on the total weight of the construction composition, wherein the additive composition includes a component from group (2a) and a component from group (2b), wherein group (2a) consists of metal chlorides and wherein group (2b) consists of silica, zeolite and apatite, and wherein group (2a) includes 70.0-99.0 wt. % of the total additive composition and group (2b) comprises 1.0-30.0 wt. % of the total additive composition; and cement, in an amount of 0.0-5.0 wt. %, based on the total weight of the construction composition. With this composition, fly ash can be used as construction material, having properties comparable or better than concrete.
摘要:
A concrete material is disclosed according to one embodiment. The concrete material may include a mixture of cement, granular rubber and boron in various forms and ratios. The boron may include boron carbide. The rubber may be recovered rubber from used automobile and/or truck tires. Various other components may be added to the cement, such as, for example, binders, water, sand, rock, or other aggregates. Embodiments described herein may be used in radiation shielding applications, such as, for example, nuclear waste facilities, nuclear storage and/or transportation casks, nuclear power plants, medical waste facilities, illicit drug detection facilities, linear accelerator facilities, etc.
摘要:
Radiation structures formed from a composition including calcium silicate, magnesium or calcium oxides and an acid phosphate are provided. The composition may also include fly ash or kaolin with or without the calcium silicate.
摘要:
Electrically gradated carbon foam materials that have changing or differing electrical properties through the thickness of the carbon foam material and methods for making these electrically gradated carbon foam materials are described herein. In some embodiments, the electrically gradated carbon foam materials exhibit increasing electrical resistivity through the thickness of the carbon foam material such that the electrical resistivity near a second surface of the carbon foam is at least 2 times greater than the electrical resistivity near a first surface of the carbon foam. These electrically gradated carbon foam materials may be used as radar absorbers, as well as in electromagnetic interference (EMI) shielding schemes.
摘要:
The mass, as that of any conventional concrete, is based on cement, aggregates, water and chemical additives that modify the properties of the concrete. According to the invention, the mass uses magnetite as an aggregate, with a highly continuous grain size in order to obtain an optimum homogeneity of the mass as well as a high density which provide an optimum barrier effect against radiation, allowing to reduce substantially the thickness of the wall required without affecting the barrier effect. The mass is ideally suited for obtaining poured concrete, concrete for bricks, concrete for slabs and dry mortar used to build radioactive premises such as radiotherapy and brachytherapy bunkers, radiology walls, etc.
摘要:
A first antiradiation concrete includes a metallic aggregate having a grain size of up to 7 mm, and at least 5.0% by weight, in particular at least 7.8%, of a boron-containing aggregate having a grain size of up to 1 mm and being finer-grained than the metallic aggregate. A second antiradiation concrete includes a boron-containing aggregate having a grain size of up to 1 mm, and between 80 and 90% by weight, in particular 85 to 89%, of a metallic aggregate having a grain size of up to 7 mm. For the second concrete, the boron-containing aggregate is between 1.0 and 1.5% by weight. To achieve a shielding action that absorbs as much heat and radiation as possible, an antiradiation shell (2) has a wall region (2a to 2z) formed from the first or second antiradiation concrete where each has a boron-containing aggregate with a grain size up to 1 mm and a metallic aggregate grain size up to 7 mm.