BACKGROUND
1. Field
[0001] The invention relates to a capsule and methods of fabricating and using the capsule.
The capsule is designed to fit within a nuclear reactor's neutron flux so that a material
within the capsule may be irradiated in the reactor's core. The capsule is further
designed to be used straight from the neutron flux source and used as an elution column
to remove ions from within the capsule that were generated by the irradiation decay
process.
2. Description of the Related Art
[0002] Technetium-99m (m is metastable) is a radionuclide used in nuclear medical diagnostic
imaging. Technetium-99m is injected into a patient which, when used with certain equipment,
is used to image the patient's internal organs. However, technetium-99m has a halflife
of only six (6) hours, therefore, readily available sources of technetium-99m are
desired.
[0003] A method for obtaining technetium-99m uses a minimum of a two-step process. First,
titanium molybdate is placed in a capsule, which is then irradiated in a nuclear reactor.
Molybdenum-98 within the titanium molybdate absorbs a neutron during the irradiation
process and becomes molybdenum-99 (Mo-99). Mo-99 is unstable and decays with a 66-hour
half-life to technetium-99m (m is metastable). After the irradiation step, the irradiated
titanium molybdate is removed from the capsule and placed in a column for elution.
Subsequently, saline is passed through the irradiated titanium molybdate to remove
the technetium-99m ions from the irradiated titanium molybdate.
SUMMARY
[0004] At least one example embodiment relates to an elution capsule. In accordance with
the example embodiment, an elution capsule includes a tube with a first end portion
having a first inside diameter, a second end portion having a second inside diameter,
and a middle portion between the first end portion and the second end portion having
an inside diameter smaller than the inside diameters of the first and second end portions.
The interface between the first end portion and the middle portion forms a first shoulder
and the interface between the second end portion and the middle portion forms a second
shoulder. The elution capsule also includes a first washer inside the first end portion
contacting the first shoulder, a first filter inside the first end portion contacting
the first washer, and a second filter inside the first end portion such that the first
filter is between the first washer and the second filter. The first end is sealed
by a first end cap. The elution capsule also includes a second washer inside the second
end portion contacting the second shoulder, a third filter inside the second end portion
contacting the second washer, and a fourth filter inside the second end portion such
that the third filter is between the second washer and the fourth filter. The second
end portion is sealed by a second end cap.
[0005] In accordance with at least one example embodiment, a method of irradiating a material
within an elution capsule is disclosed. In accordance with the example embodiment,
the elution capsule includes a tube with a first end portion having a first inside
diameter, a second end portion having a second inside diameter, and a middle portion
having an inside diameter smaller than the inside diameters of the first and second
end portions. The middle portion is between the first end portion and the second end
portion and is configured to hold the material. The interface between the first end
portion and the middle portion forms a first shoulder and the interface between the
second end portion and the middle portion forms a second shoulder. A first washer
is inside the first end portion and contacts the first shoulder. A first filter is
inside the first end portion and contacts the first washer. A second filter is inside
the first end portion and is positioned such that the first filter is between the
first washer and the second filter. A first end cap is provided in the first end portion
to seal-off the first end portion. A second washer inside the second end portion and
contacts the second shoulder. A third filter is inside the second end portion and
contacts the second washer. A fourth filter inside the second end portion is provided
such that the third filter is between the second washer and the fourth filter. A second
end cap is provided in the second portion to seal-off the second end portion. The
method, according to the example embodiment, includes placing the sealed elution capsule,
with the material in the middle portion of the elution capsule in a neutron flux source
and irradiating the capsule and its contents in the reactor's core.
[0006] At least one example embodiment related to a method of eluting a material enclosed
in a sealed elution capsule is provided. The method includes placing the sealed elution
capsule enclosing the material into a nuclear reactor, irradiating the sealed elution
capsule and material in a reactor, removing the sealed elution capsule and irradiated
material from the reactor, and performing an elution step by puncturing a first end
portion of the elution capsule with a needle to supply a solution to the elution capsule
and puncturing a second end portion with a needle to provide a vacuum to draw the
solution through the irradiated material to collect the eluant.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Example embodiments of the present invention will be more clearly understood from
the following detailed description taken in conjunction with the accompanying drawings.
FIG.1 is a section view of an irradiation/elution capsule in accordance with an example
embodiment of the present invention;
FIG. 2 is an exploded view of an irradiation/elution capsule in accordance with an
example embodiment of the present invention;
FIG. 3 is a section view of a multidiameter tube used in an irradiation /elution capsule
in accordance with an example embodiment of the invention;
FIGS. 4 and 5 are plan views of washers used in an example irradiation/ elution capsule
in accordance with an example embodiment of the invention;
FIGS. 6 and 7 are plan views of filters used in an example irradiation elution capsule
in accordance with an example embodiment of the invention;
FIGS. 8-13 are views of end caps used in an irradiation/elution capsule in accordance
with an example embodiment of the invention;
FIG. 14 are views of a seals for sealing the ends of an example irradiation/elution
capsule in accordance with an example embodiment of the invention
FIGS. 15-16 illustrate steps for using an irradiation/elution capsule in accordance
with an example embodiment of the invention.
DETAILED DESCRIPTION OF THE EXAMPLE EMBODIMENTS
[0008] Example embodiments of the invention will now be described more fully with reference
to the accompanying drawings, in which example embodiments are shown. The invention
may, however, be embodied in different forms and should not be construed as limited
to the embodiments set forth herein. Rather, these embodiments are provided so that
this disclosure will be thorough and complete, and will fully convey the scope of
the invention to those skilled in the art. In the drawings, the sizes of components
may be exaggerated for clarity.
[0009] It will be understood that when an element or layer is referred to as being "on",
"connected to", or "coupled to" another element or layer, it can be directly on, connected
to, or coupled to the other element or layer or intervening elements or layers that
may be present. In contrast, when an element is referred to as being "directly on",
"directly connected to", or "directly coupled to" another element or layer, there
are no intervening elements or layers present. As used herein, the term "and/or" includes
any and all combinations of one or more of the associated listed items.
[0010] It will be understood that, although the terms first, second, etc. may be used herein
to describe various elements, components, regions, layers, and/or sections, these
elements, components, regions, layers, and/or sections should not be limited by these
terms. These terms are only used to distinguish one element, component, region, layer,
and/or section from another element, component, region, layer, and/or section. Thus,
a first element, component, region, layer, or section discussed below could be termed
a second element, component, region, layer, or section without departing from the
teachings of example embodiments.
[0011] Spatially relative terms, such as "beneath", "below", "lower", "above", "upper",
and the like, may be used herein for ease of description to describe one element or
feature's relationship to another element(s) or feature(s) as illustrated in the figures.
It will be understood that the spatially relative terms are intended to encompass
different orientations of the device in use or operation in addition to the orientation
depicted in the figures. For example, if the device in the figures is turned over,
elements described as "below" or "beneath" other elements or features would then be
oriented "above" the other elements or features. Thus, the exemplary term "below"
can encompass both an orientation of above and below. The device may be otherwise
oriented (rotated 90 degrees or at other orientations) and the spatially relative
descriptors used herein interpreted accordingly.
[0012] Embodiments described herein will refer to plan views and/or cross-sectional views
by way of ideal schematic views. Accordingly, the views may be modified depending
on manufacturing technologies and/or tolerances. Therefore, example embodiments are
not limited to those shown in the views, but include modifications in configuration
formed on the basis of manufacturing processes. Therefore, regions exemplified in
figures have schematic properties and shapes of regions shown in figures exemplify
specific shapes or regions of elements, and do not limit example embodiments.
[0013] FIGS. 1 - 3 represent an example embodiment of the present invention. The example
embodiment, as shown in FIGS. 1-3, includes a hollow cylindrically shaped multidiameter
tube 10. The tube 10 is hollow such that a cross-section of the multidiameter tube
has an annular shape. The tube 10 has a constant outer diameter D1, however, the inner
diameter of the tube 10 varies along the length of the tube 10. For example, the tube,
as shown in FIG. 1, includes three portions: a first end portion 12 located at one
end of the multidiameter tube 10, a second end portion 14 located at another end of
the multidiameter tube 10, and a middle portion 16 between the first end portion 12
and the second end portion 14. In this example embodiment of the invention, the inner
diameter D4 of the middle portion 16 may be smaller than the inner diameters D2 and
D3 of the end portions 12 and 14. In addition, the inner diameter of the first end
portion D2 and the inner diameter of the second end portion D3 may be equal.
[0014] The first end portion 12 and the second end portion 14 may have lengths P1 and P2,
respectively. As shown in FIG. 3, the lengths P1 and P2 may be equal. The interface
between the first end portion 12 and the middle portion 16 forms a first shoulder
100 and the interface between the second end portion 14 and the middle portion 16
forms a second shoulder 110. Because the lengths P1 and P2 may be equal and because
the diameters D1 and D2 may likewise be equal, the multidiameter tube 10 illustrated
in FIGS. 1-3 may have a symmetric configuration.
[0015] The example capsule 1 for holding, irradiating and eluting a material in accordance
with FIGS. 1-3 also includes first and second washers 20 and 60 positioned inside
the first end portion 12 and the second end portion 14, respectively. The washers
20 and 60, as shown in FIGS. 1, 2, 4 and 5, are short hollow cylinders with annular
cross-sections. The washer 20 has an outside diameter D6 larger than the inside diameter
D4 of the middle portion 16 and smaller than the inside diameter D2 of the first end
portion 12. The washer 20 has an inside diameter D5 that may be smaller, equal to,
or larger than the diameter of the inside diameter D4 of the middle portion 16. The
washer 60 has an outside diameter D8 larger than the inside diameter D4 of the middle
portion 16 and smaller than the inside diameter D3 of the second end portion 14. The
washer 60 has an inside diameter D7 that may be smaller, equal to, or larger than
the diameter of the inside diameter D4 of the middle portion 16. As shown in FIGS.
1-2, the washer 20 is placed inside the first end portion 12 and against the shoulder
100. The washer 60 is placed in the second end portion 14 and against the shoulder
110.
[0016] The example capsule 1 for holding, irradiating, and eluting a material also includes,
first and second filters 30 and 40 in the first end portion 12 and third and fourth
filters 70 and 80 in the second end portion 14 of the multidiameter tube 10.
[0017] The first filter 30 is placed in the first end portion such that the washer 20 is
between the first filter 30 and the shoulder 100 and the second filter 40 is placed
in the first end portion 12 such that the first filter 30 is between the second filter
40 and the washer 20. The third filter 70 is placed in the second end portion 14 such
that the washer 60 is between the third filter 70 and the shoulder 110 and the fourth
filter 80 is placed in the second end portion 14 such that the third filter 70 is
between the fourth filter 80 and the washer 60.
[0018] The first through fourth filters may be made of various materials. For example, the
first filter 30 and the third filter 70 may be made from glass wool. The glass wool
may be made from a borosilicate or quartz glass. The second filter 40 and the fourth
filter 80, may be circular glass frits as shown in FIGS. 1, 2, and 6-7 which resemble
short cylinders or disks. The glass frits may be made from various materials such
as borosilicate glass, quartz glass, polyethylene, resin, or some other material that
will structurally support a material within the elution tube and act as a filter to
prevent material from traversing down a flow path through the elution tube. The circular
glass frit 40 has an outer diameter D9 smaller than the inner diameter D2 of the first
end portion 12 but greater than the inner diameter D5 of the washer 20. The circular
glass frit 80 has an outer diameter D10 smaller than the inner diameter D3 of the
second end portion 14 but larger than the inner diameter D7 of the washer 60. Although
circular glass frits are used as second and fourth filters 40 and 80, the invention
is not limited thereto.
[0019] The example capsule 1 for holding, irradiating, and eluting a material also includes
end caps 50 and 90 configured to seal the first end portion 12 and the second end
portion 14 of the multidiameter tube 10, respectively. In accordance with the example
embodiment illustrated in FIGS. 1-2, the end caps 50 and 90 may include tapered hollow
cylindrical body parts 52 and 92 with covers 53 and 93 as shown in FIGS. 1, 2 and
8-13, allowing the end caps 50 and 90 to be press fit into the first and second end
portions 12 and 14 of the multidiameter tube. Because the ends of the multidiameter
tube 1 are sealed by press fitting the end caps 50 and 90 into the first and second
end portions 12 and 14, the end caps 50 and 90 should be made from a soft material
which will accommodate yielding during the press fit process. For example, the end
caps may be made of aluminum.
[0020] The hollow cylindrical body part 52 may be tapered so that the outer diameter D12
of a portion of the hollow cylindrical body part 52 facing the center of the multidiameter
tube 10 is smaller than an outer diameter D14 of the hollow cylindrical body part
52 attached to the cover 53. The diameter D12 must be smaller than the inner diameter
D2 of the first end portion 12 of the multidiameter tube 10 so that the end of the
hollow body part 52 facing the center of the multidiameter tube 10 may enter the first
end portion 12. However, the outer diameter D14 of the cylindrical body part 52 attached
to the cover 53 should be slightly larger than the inner diameter D2 of the first
end portion 12 of the multidiameter tube 10 so that when the end cap 50 is press fit
into the first end portion 12 of the multidiameter tube 10 the first end portion is
sealed. Additionally, the inner diameter D11 of the hollow body part 52 should be
smaller than the diameter D9 of the frit 40 to prevent the frit 40 from passing into
the hollow body part 52.
[0021] The length L1 of the hollow body part 52 should be long enough to accommodate a needle
which may be passed through the cover 53 during an elution process. The length L1
of the hollow body part 52, therefore, should be at least as long as the needle used
to introduce or remove a liquid into or from the example capsule 1 for holding, irradiating,
and eluting a material. Because the length L1 of the hollow body part 52 is at least
as long as the aforementioned needle, the hollow body part protects the first and
second filter from being damaged by the needle as the needle is introduced into the
capsule.
[0022] The cover 53 of the end cap 50 has a diameter D15 larger than the inner diameter
D2 of the first end portion 12 of the multidiameter tube to prevent the end cap 50
from completely passing into the first end portion 12. Because the cover 53 acts as
a stop, the first and second filters 30 and 40 may be protected from being crushed
by the hollow body 52 of the end cap 50 during the press fit process. Additionally,
the cover 53 of the end cap 50 should be thin enough to allow puncture by a needle
used in an elution process.
[0023] The hollow cylindrical body part 92 may be tapered so that the outer diameter D16
of a portion of the hollow cylindrical body part 92 facing the center of the multidiameter
tube 10 is smaller than an outer diameter D18 of the hollow cylindrical body part
92 attached to the cover 93. The diameter D16 must be smaller than the inner diameter
D3 of the second end portion 14 of the multidiameter tube 10 so that the end of the
hollow body part 92 facing the center of the multidiameter tube 10 may enter the second
end portion 14. However, the outer diameter D18 of the cylindrical body part 92 attached
to the cover 93 should be slightly larger than the inner diameter D3 of the second
end portion 14 of the multidiameter tube 10 so that when the end cap 90 is press fit
into the second end portion 14 of the multidiameter tube 10 the second end portion
14 forms a mechanical seal. Additionally, the inner diameter D17 of the hollow body
part 92 should be smaller than the diameter D10 of the frit 80 to prevent the frit
80 from passing into the hollow body part 92.
[0024] The length L2 of the hollow body part 92 should be long enough to accommodate a needle
which may be passed through the cover 93 during an elution process. The length L2
of the hollow body part 92, therefore, should be at least as long as the needle used
to introduce or remove a liquid into or from the example capsule for holding, irradiating,
and eluting a material. Because the length L2 of the hollow body part 92 is at least
as long as the aforementioned needle, the hollow body part 92 protects the third and
fourth filters 70 and 80 from being damaged by the needle as the needle is introduced
into the capsule.
[0025] The cover 93 of the end cap 90 has a diameter D19 larger than the inner diameter
D3 of the second end portion 14 of the multidiameter tube 10 to prevent the end cap
90 from completely passing into the second end portion 14. Because the cover 93 acts
as a stop, the third and fourth filters 70 and 80 may be protected from being crushed
by the hollow body 92 of the end cap 90 during the press fit process. Additionally,
the cover 93 of the end cap 90 should be thin enough to allow puncture by a needle
used in an elution process.
[0026] An adhesive may be applied to the outer surfaces of the hollow body parts 52 and
92 before the end caps 50 and 90 are press fit into the first and second end portions
12 and 14. The adhesive may provide additionally sealing to prevent materials in the
capsule from escaping.
[0027] The example capsule 1 for holding, irradiating, and eluting a material may also include
a first and second seals 200 and 300 for covering the end caps 50 and 90 after the
end caps 50 and 90 have been press fit into the first and second end portions 12 and
14, respectively. Examples of the seals 200 and 300 are illustrated in FIG. 14. The
first and second seals include a hollow cylindrical body parts 210 and 310 and are
closed at one end by end parts 220 and 320. The seals may be made from a flexible
material, for example, a non-hardening rubber, so that the seals 200 and 300 can be
snug fit over the first and second end portions 12 and 14 to create a second seal.
The end parts 220 and 320 of the seals 200 and 300 must be thin enough to allow puncture
by a needle used in an elution process. Additionally, the seals 200 and 300 may be
epoxied onto the ends of the multidiameter tube 10 by applying epoxy to the inner
surfaces of the cylindrical body parts 210 and 310 before the seals 200 and 300 are
fitted over the first and second end portions of 12 and 14. The epoxy applied to the
inner surfaces of the cylindrical body parts 210 and 310 may provide an extra seal
to prevent materials within the capsule 1 from escaping.
[0028] The multidiameter tube 10, the end caps 50 and 90, and the washers 20 and 60, should
be made from materials that have a low nuclear cross section to avoid absorbing neutrons.
Examples of such materials include zirconium, quartz, aluminum or alloys including
zirconium, quartz, glass and aluminum. For example, the multidiameter tube 10, end
caps 50 and 90, and the washers 20 and 60, may be made from zircaloy-2 or alternatively
from aluminum 6061, high purity aluminum, and 4N and 5N aluminum.
[0029] Materials having low nuclear cross section are readily available from manufacturers
and are often provided as bar stock. For example, cylinders of zirconium are readily
available.
[0030] The multidiameter tube 10 may be fabricated by implementing a series of boring operations
on a solid cylinder, for example, a solid cylinder of zirconium. The cylinder may
have an outer diameter D1 and a length. The length of the cylinder may be determined
based on the size of the nuclear reactor in which the cylinder will be irradiated
and/or the size of a generator used in an elution process. A center of the cylinder
may be bored out to a diameter of D4 transforming the solid cylinder into a hollow
cylindrical tube. The hollow cylindrical tube may have a constant annular cross section
with an inner diameter D4 and an outer diameter D1.
[0031] One end of the hollow tube may have the diameter increased by a second boring operation
to form a first end portion 12 having a length of P1 and an inner diameter of D2.
A second end of the hollow tube may likewise have the diameter increased by a third
boring operation to form a second end portion 14 having a length P2 and an inner diameter
D3. The length P1 should be deep enough to accommodate the above described filters
30 and 40, the washer 20, and the hollow part 52 of the end cap 50. Likewise, the
length P2 should be deep enough to accommodate the above described filters 70 and
80, the washer 60, and the hollow part 92 of the end cap 90. The second and third
boring operations transform the hollow cylindrical tube into a hollow multidiameter
cylindrical tube 10 (see FIG. 3). The first end portion 12 has an annular cross section
with an inner diameter D2 and an outer diameter D1 and the second end portion 14 has
an annular cross section with an inner diameter D3 and an outer diameter D1. The portion
of the tube between the first end portion 12 and the second end portion 14 constitutes
a middle portion 16 with an annular cross section having an inner diameter D4 and
an outer diameter D1.
[0032] The depths P1 and P2 of the first end portion and the second end portion 12 and 14
of the multidiameter tube 10 by the second and third boring operations may be the
same. In addition, the inner diameters D2 and D3 of the first and second end portions
12 and 14 may be the same. Accordingly, the multidiameter tube 10 may be fabricated
to produce a symmetrical structure.
[0033] The washers 20 and 60 may be fabricated by processes similar to those used in making
the multidiameter tube 10. Because the washers 20 and 60 may be made by the same process,
the process for making washer 60 is omitted for the sake of brevity. As a starting
point, washers may be fabricated from a cylinder of zirconium having an outer diameter
of D6 may be provided. The diameter D6 should be smaller than the diameter D2 associated
with the first end portion 12 of the multidiameter tube 10. The cylinder may have
a length that should be at least as long as a desired thickness for the washer. The
cylinder may have the middle bored out to create a hollow tube. The tube has an annular
cross section with an inner diameter D5 and an outer diameter D6 (see FIG. 4). An
end portion of the tube may be cut along a cut line to form the washer 20 with a desired
thickness.
[0034] The end caps 50 and 90 may be fabricated by processes similar to those used in making
the multidiameter tube 10. Because the end caps 50 and 90 may be made by the same
process, the process for making the end cap 90 is omitted for the sake of brevity.
[0035] As a starting point, end caps may be fabricated by a cylinder of zirconium having
an outer diameter D14 may be provided. The diameter D14 should be larger than the
diameter D2 of the first end portion 12 of the multidiameter tube 10 (see Figure 3).
The cylinder is slightly longer than a length of a needle used to introduce or remove
saline solution into or from the capsule 1 during the elution process. The cylinder
may be placed in a die which fixes a portion of the cylinder. A first force may be
applied to one end of the cylinder to deform the end of the cylinder to create a cover
53. The cover has a diameter D15 larger than the diameter D14 of the cylindrical body
52.
[0036] After the cover 53 has been formed, a portion of the cylinder below the cover 53
may be bored out to create a hollow body portion. The hollow body portion resembles
a circular tube having an annular cross section with an inner diameter D11 and an
outer diameter D14. After the hollow body portion is formed, a second force may be
applied laterally to the hollow body portion to deform the hollow body portion into
a tapered shape. Application of the second force transforms the hollow body portion
into a tapered hollow body 52. The end of the tapered hollow body 52 away from the
cover 53 has an annular cross section having an inner diameter D11 and an outer diameter
D12. The outer diameter D12 should be formed to be smaller than the inner diameter
D2 of the first end portion 12 in order to allow the end cap 50 to enter into the
first end portion 12.
[0037] Having fabricated the multidiameter tube 10, the washers 20 and 60, and the end caps
50 and 90 the capsule 1 are assembled as shown in FIG. 2. The washer 20 is placed
into the first end portion 12 so that the washer 20 bears up against the first shoulder
100. A first filter 30, for example, glass wool made from borosilicate glass, is placed
in the first end portion 12 so that washer 20 is between the first filter 30 and the
shoulder 100. A second filter 40, for example, a glass frit made of borosilicate glass,
is provided in the first end portion 12 so that first filter 30 is between the second
filter 40 and the washer 20. The end cap 50 is inserted and may be press fit into
the first end portion 12 thus sealing the first end portion 12. An epoxy may be provided
on the outer surfaces of the hollow body part 52 of the end cap 50 before the press
fitting operation to provide an extra added sealing means.
[0038] Formation of the capsule is completed by sealing the second end. The washer 60 is
placed into the second end portion 14 so that the washer 60 bears up against the second
shoulder 110. A third filter 70, for example, glass wool made from borosilicate glass,
is placed in the second end portion 14 so that washer 60 is between the third filter
70 and the shoulder 110. A fourth filter 80, for example, a glass frit made of borosilicate
glass, is provided in the second end portion 14 so that third filter 70 is between
the fourth filter 80 and the washer 60. The end cap 90 is inserted and may be press
fit into the second end portion 14 thus sealing the second end portion 14. An epoxy
may be provided on the outer surfaces of the hollow body part 92 of end cap 90 before
the press fitting operation to provide an extra added sealing means.
[0039] In addition to the above steps for fabricating the example capsule 1, extra seals
200 and 300 (see FIGS. 2 and 14) may be provided and placed on the ends of the capsule
I after the first and second end portions 12 and 14 are sealed. The seals 200 and
300 may be provided for an extra seal. These seals may be made from a flexible material
such as rubber and may be fabricated to provide a snug fit over the end portions of
12 and 14, of the capsule 1. The seals may include hollow body parts 210 and 310 and
cover parts 220 and 320. The cover parts 220 and 320 should be sufficiently thin to
allow for puncture by a needle in an elution process. In addition, epoxy may be applied
to the inside surfaces of the hollow body parts 210 and 310 before the seals 200 and
300 are placed on the end portions 12 and 14 to provide for extra means for sealing
the end portions of 12 and 14, of capsule 1.
[0040] As disclosed, the example capsule 1 includes a multidiameter tube 10 with a first
end portion 12, a second end portion 14, and a middle portion 16 between the end portion
12 and 14. When the tube is in use, the middle portion 16 holds a material for an
irradiation process. For example, the middle portion 16 may hold titanium molybdate,
zirconium molybdate, titanium tungstenate, zirconyl tungstenate, or other ion exchange
resin/gel matrix for elution. The material, for example, may be added to the middle
portion 16 after the first end portion 12 has been assembled and sealed by the end
cap 50 as described above. After the material is added to the middle portion 16, the
second end portion 14 may be assembled and sealed as described above.
[0041] The sealed capsule 1 (without the seals 200 and 300) including the material to be
irradiated may be irradiated in a nuclear reactor. After the irradiation step, the
capsule may be removed from the reactor and the seals 200 and 300 may be fixed to
the capsule as described above. Referring to FIGS. 15 and 16 a method of eluting the
ions generated by the irradiation step and subsequent radioactive decay is described.
[0042] As shown in FIGS. 15 and 16, the capsule 1 includes an irradiated substance 6000.
The elution process comprises two steps. The first step includes puncturing one end
of the capsule 1 with a needle 7100 attached to a device 7000 for supplying a liquid,
for example, distilled water, deionized water, saline, oxidizers, acids, bases, or
any other water based solution, to the example capsule 1. As shown in FIG. 15, the
seal 200 and the end cap 50 may be punctured by the needle 7100. However, because
the length of the needle is shorter than the length of the hollow body portion 52,
the first and second filters 30 and 40 of capsule 1, are not damaged by the needle.
In order to draw the liquid through the irradiated substance 6000 as shown in FIG.
16, a needle 8100 attached to a vacuum system 8000, e.g. a vacuum bottle, punctures
the end cap 90 and the seal 300. However, because the needle 8100 is shorter than
the length of the hollow body 92 of the end cap 90, the third and fourth filters 70
and 80 of capsule 1, are not damaged by the needle 8100. The vacuum from the vacuum
system 8000 draws the fluid from the device 7000, through the irradiated material
6000, and into the vacuum system 8000. Accordingly, ions generated during the irradiation
decay process may be collected in the vacuum system 8000.
1. An elution capsule (1) comprising:
a tube (10) with a first end portion (12) having a first inside diameter (D2), a second
end portion (14) having a second inside diameter (D3), and a middle portion (16) between
the first end portion and the second end portion having an inside diameter (D4) smaller
than the inside diameters of the first and second end portions, wherein an interface
between the first end portion and the middle portion forms a first shoulder (100)
and an interface between the second end portion and the middle portion forms a second
shoulder (110);
a first washer (20) inside the first end portion contacting the first shoulder;
a first filter (30) inside the first end portion contacting the first washer;
a second filter (40) inside the first end portion such that the first filter is between
the first washer and the second filter;
a first end cap (50) sealing the first end portion;
a second washer (60) inside the second end portion contacting the second shoulder;
a third filter(70) inside the second end portion contacting the second washer;
a fourth filter (80) inside the second end portion such that the third filter is between
the second washer and the fourth filter; and
a second end cap (90) sealing the second end portion.
2. The elution capsule of claim 1, wherein the cross-sections of the first end portion,
the second end portion, and the middle portion are annular.
3. The elution capsule of claim 1 or 2, wherein the first inside diameter and the second
inside diameter are the same.
4. The elution capsule of any one of the preceding claims, wherein a length of the first
end portion and a length of the second end portion are the same.
5. The elution capsule of any one of the preceding claims, wherein first and third filters
are glass wool and the second and fourth filters are one of glass frits and porous
discs, the second and fourth filters being formed from one of borosilicate glass,
quartz glass, polyethylene, and resin.
6. The elution capsule of claim 5, wherein the glass wool includes at least one of borosilicate
glass wool, quartz glass wool, and glass fiber.
7. The elution capsule of any one of the preceding claims, wherein the first end cap
comprises:
a hollow body (52), wherein an outside surface of the hollow body is tapered to allow
for press fitting the first end cap into the first end portion to create a seal at
the first end portion; and
a cover (53) configured for puncturing by needles and configured to bear against an
outside surface of the first end portion.
8. The elution capsule of claim 7, wherein the hollow body of the first end cap has an
annular cross section and an outside diameter (D12) of the cross section varies along
an axis of the hollow body and the cover has a solid circular cross section with an
outer diameter (D15) greater than the inner diameter of the first end portion.
9. The elution capsule of any one of the preceding claims, wherein the first washer has
an annular cross section with an outside diameter (D6) equal to or less than the first
inside diameter of the first portion end and the second washer has an annular cross
section with an outside diameter (D8) equal to or less than the second inside diameter
of the second end portion.
10. The elution capsule of any one of the preceding claims, wherein the tube is made from
at least one of high purity zirconium, aluminum, glass and quartz.
11. The elution capsule of any one of the preceding claims, further comprising:
a first epoxy layer between the first end cap and the first end portion and a second
epoxy layer between the second end cap and the second end portion.
12. The elution capsule of any one of the preceding claims, further comprising:
a first flexible seal on an outside of the first end portion and a second flexible
seal on an outside of the second end portion.
13. The elution capsule of claim 12, further comprising:
a first adhesive layer between the first flexible seal and the first end portion and
a second adhesive layer between the second flexible seal and the second end portion.
14. A method of irradiating a material in an elution capsule (1), the elution capsule
including a tube (10) with a first end portion (12) having a first inside diameter,
a second end portion (14) having a second inside diameter, and a middle portion (16)
having an inside diameter smaller than the inside diameters of the first and second
end portions, the middle portion being between the first end portion and the second
end portion and configured to hold the material, an interface between the first end
portion and the middle portion forms a first shoulder (100) and an interface between
the second end portion and the middle portion forms a second shoulder (110), a first
washer (20) inside the first end portion contacting the first shoulder, a first filter(30)
inside the first end portion contacting the first washer, a second filter (40) inside
the first end portion such that the first filter is between the first washer and the
second filter, a first end cap sealing the first end portion, a second washer (60)
inside the second end portion contacting the second shoulder, a third filter (70)
inside the second end portion contacting the second washer, a fourth filter (80) inside
the second end portion such that the third filter is between the second washer and
the fourth filter, and a second end cap sealing the second end portion, the method
comprising:
placing the elution capsule with the material in the middle portion of the elution
capsule in a neutron flux source; and
irradiating the capsule and the material in the neutron flux source.
15. The method of claim 14, wherein the material includes one of titanium molybdate, zirconium
molybdate, titanium tungstenate, and zirconyl tungstenate.
1. Elutionskapsel (10), aufweisend:
ein Rohr (10) mit einem einen ersten Innendurchmesser (D2) aufweisenden ersten Endabschnitt
(12), einem einen zweiten Innendurchmesser (D3) aufweisenden zweiten Endabschnitt
(14) und mit einem Mittelabschnitt (16) zwischen dem ersten Endabschnitt und dem zweiten
Endabschnitt mit einem Innendurchmesser (D4), der kleiner als der Innendurchmesser
des ersten und zweiten Endabschnittes ist, wobei eine Schnittstelle zwischen dem ersten
Endabschnitt und dem Mittelabschnitt eine erste Schulter (100) ausbildet und eine
Schnittstelle zwischen dem zweiten Endabschnitt und dem Mittelabschnitt eine zweite
Schulter (110) ausbildet;
eine erste Scheibe (20) in dem ersten Endabschnitt in Kontakt mit der ersten Schulter;
ein erstes Filter (30) in dem ersten Endabschnitt in Kontakt mit der ersten Scheibe;
ein zweites Filter (40) in dem ersten Endabschnitt dergestalt, dass sich das erste
Filter zwischen der ersten Scheibe und dem zweiten Filter befindet;
eine erste Endkappe (50), die den ersten Endabschnitt verschließt;
eine zweite Scheibe (60) in dem zweiten Endabschnitt in Kontakt mit der zweiten Schulter;
ein drittes Filter (70) in dem zweiten Endabschnitt in Kontakt mit der zweiten Scheibe;
ein viertes Filter (80) in dem zweiten Endabschnitt dergestalt, dass sich das dritte
Filter zwischen der zweiten Scheibe und dem vierten Filter befindet; und
eine zweite Endkappe (90), die den zweiten Endabschnitt verschließt.
2. Elutionskapsel nach Anspruch 1, wobei die Querschnitte des ersten Endabschnittes,
des zweiten Endabschnittes und des Mittelabschnittes ringförmig sind.
3. Elutionskapsel nach Anspruch 1 oder 2, wobei der erste Innendurchmesser und der zweite
Innendurchmesser gleich sind.
4. Elutionskapsel nach einem der vorstehenden Ansprüche, wobei eine Länge des ersten
Endabschnittes und eine Länge des zweiten Endabschnittes gleich sind.
5. Elutionskapsel nach einem der vorstehenden Ansprüche, wobei das erste und zweite Filter
Glaswolle ist, und das zweite und vierte Filter eines von Glasfritten und porösen
Scheiben ist, wobei das zweite und vierte Filter aus einem von Borsilikatglas, Quarzglas,
Polyethylen und Harz ausgebildet sind.
6. Elutionskapsel nach Anspruch 5, wobei die Glaswolle wenigstens eines von Borsilikatglaswolle,
Quarzglaswolle und Glasfaser enthält.
7. Elutionskapsel nach einem der vorstehenden Ansprüche, wobei die erste Endkappe aufweist:
einen Hohlkörper (52), wobei eine Außenoberfläche des Hohlkörpers abgeschrägt ist,
um eine Presspassung der ersten Endkappe in dem ersten Endabschnitt zum Erzeugen einer
Dichtung an dem ersten Endabschnitt zu ermöglichen; und
einen Deckel (53), der zur Punktierung durch Nadeln ausgestaltet ist und zum Anliegen
an einer Außenoberfläche des ersten Endabschnittes ausgestaltet ist.
8. Elutionskapsel nach Anspruch 7, wobei der Hohlkörper der ersten Endkappe einen ringförmigen
Querschnitt hat und ein Außendurchmesser (D12) des Querschnittes entlang einer Achse
des Hohlkörpers variiert und der Deckel einen Vollkreisquerschnitt mit einem Außendurchmesser
(D15) hat, der größer als der Innendurchmesser des ersten Endabschnittes ist.
9. Elutionskapsel nach einem der vorstehenden Ansprüche, wobei die erste Scheibe einen
ringförmigen Querschnitt mit einem Außendurchmesser (D6) gleich oder kleiner als ein
erster Innendurchmesser des ersten Endabschnittes hat und die zweite Scheibe einen
ringförmigen Querschnitt mit einem Außendurchmesser (D8) gleich oder kleiner als der
zweite Innendurchmesser des zweiten Endabschnittes hat.
10. Elutionskapsel nach einem der vorstehenden Ansprüche, wobei das Rohr aus wenigstens
einem von hochreinem Zirkon, Aluminium, Glas und Quarz besteht.
11. Elutionskapsel nach einem der vorstehenden Ansprüche, ferner aufweisend:
eine erste Epoxidschicht zwischen der ersten Endkappe und dem ersten Endabschnitt
und eine zweite Epoxidschicht zwischen der zweiten Endkappe und dem zweiten Endabschnitt.
12. Elutionskapsel nach einem der vorstehenden Ansprüche, ferner aufweisend:
eine erste flexible Dichtung auf einer Außenseite des ersten Endabschnittes und eine
zweite flexible Dichtung auf einer Außenseite des zweiten Endabschnittes.
13. Elutionskapsel nach Anspruch 12, ferner aufweisend:
eine erste Kleberschicht zwischen der ersten flexiblen Dichtung und dem ersten Endabschnitt
und eine zweite Kleberschicht zwischen der zweiten flexiblen Dichtung und dem zweiten
Endabschnitt.
14. Verfahren zum Bestrahlen eines Materials in einer Elutionskapsel (1), wobei die Elutionskapsel
ein Rohr (10) mit einem einen ersten Innendurchmesser aufweisenden ersten Endabschnitt
(12), einem einen zweiten Innendurchmesser aufweisenden zweiten Endabschnitt (14)
und einen Mittelabschnitt (16) mit einem Innendurchmesser, der kleiner als der Innendurchmesser
des ersten und zweiten Endabschnittes ist, enthält, wobei sich der Mittenabschnitt
zwischen dem ersten und zweiten Endabschnitt befindet und zum Halten des Materials
ausgestaltet ist, eine Schnittstelle zwischen dem ersten Endabschnitt und dem Mittelabschnitt
eine erste Schulter (100) ausbildet, und eine Schnittstelle zwischen dem zweiten Endabschnitt
und dem Mittelabschnitt eine zweite Schulter (110) ausbildet, eine erste Scheibe (20)
innerhalb des ersten Endabschnittes in Kontakt mit der ersten Schulter steht, ein
erstes Filter (30) in dem ersten Endabschnitt in Kontakt mit der ersten Scheibe steht,
ein zweites Filter (40) in dem ersten Endabschnitt dergestalt angeordnet ist, dass
sich das erste Filter zwischen der ersten Scheibe und dem zweiten Filter befindet,
eine erste Endkappe den ersten Endabschnitt verschließt, eine zweite Scheibe (60)
in dem zweiten Endabschnitt in Kontakt mit der zweiten Schulter steht, ein drittes
Filter (70) in dem zweiten Endabschnitt in Kontakt mit der zweiten Scheibe steht,
ein viertes Filter (80) in dem zweiten Endabschnitt dergestalt angeordnet ist, dass
sich das dritte Filter zwischen der zweiten Scheibe und dem vierten Filter befindet,
und eine zweite Endkappe (90) den zweiten Endabschnitt verschließt, wobei das Verfahren
die Schritte aufweist:
Platzieren der Elutionskapsel mit dem Material in dem Mittenabschnitt der Elutionskapsel
in einer Neutronenflussquelle; und
Bestrahlen der Kapsel und des Materials in der Neutronenflussquelle.
15. Verfahren nach Anspruch 14, wobei das Material eines von Titanmolybdat, Zirkonmolybdat,
Titanwolframat und Zirkonylwolframat enthält.
1. Capsule d'élution (1), comprenant :
un tube (10) avec une première partie d'extrémité (12) ayant un premier diamètre intérieur
(D2), une deuxième partie d'extrémité (14) ayant un deuxième diamètre intérieur (D3),
et une partie médiane (16) située entre la première partie d'extrémité et la deuxième
partie d'extrémité et ayant un diamètre intérieur (D4) inférieur aux diamètres intérieurs
des première et deuxième parties d'extrémité, où une interface entre la première partie
d'extrémité et la partie médiane forme un premier épaulement (100), et une interface
entre la deuxième partie d'extrémité et la partie médiane forme un deuxième épaulement
(110);
une premier rondelle (20) se trouvant à l'intérieur de la première partie d'extrémité,
en contact avec le premier épaulement;
un premier filtre (30) se trouvant à l'intérieur de la première partie d'extrémité,
en contact avec la première rondelle;
un deuxième filtre (40) se trouvant à l'intérieur de la première partie d'extrémité,
de manière à ce que le premier filtre se trouve entre la première rondelle et le deuxième
filtre;
un premier bouchon (50) fermant de manière étanche la première partie d'extrémité;
une deuxième rondelle (60) se trouvant à l'intérieur de la deuxième partie d'extrémité,
en contact avec le deuxième épaulement;
un troisième filtre (70) se trouvant à l'intérieur de la deuxième partie d'extrémité,
en contact avec la deuxième rondelle;
un quatrième filtre (80) se trouvant à l'intérieur de la deuxième partie d'extrémité,
de manière à ce que le troisième filtre se trouve entre la deuxième rondelle et le
quatrième filtre; et
un deuxième bouchon (90) fermant de manière étanche la deuxième partie d'extrémité.
2. Capsule d'élution selon la revendication 1, dans laquelle les sections transversales
de la première partie d'extrémité, de la deuxième partie d'extrémité et de la partie
médiane sont annulaires.
3. Capsule d'élution selon la revendication 1 ou 2, dans laquelle le premier diamètre
intérieur et le deuxième diamètre intérieur sont identiques.
4. Capsule d'élution selon l'une quelconque des revendications précédentes, dans laquelle
une longueur de la première partie d'extrémité et une longueur de la deuxième partie
d'extrémité sont identiques.
5. Capsule d'élution selon l'une quelconque des revendications précédentes, dans laquelle
les premier et troisième filtres sont en laine de verre, et les deuxième et quatrième
filtres sont constitués d'une matière parmi le verre fritté et des disques poreux,
les deuxième et quatrième filtres étant formés d'une matière parmi le verre de borosilicate,
le verre de quartz, le polyéthylène et la résine.
6. Capsule d'élution selon la revendication 5, dans laquelle la laine de verre comporte
au moins une matière parmi la laine de verre de borosilicate, la laine de verre de
quartz et la fibre de verre.
7. Capsule d'élution selon l'une quelconque des revendications précédentes, dans laquelle
le premier bouchon comprend :
un corps creux (52), où une surface extérieure du corps creux est conique pour permettre
un ajustage serré du premier bouchon dans la première partie d'extrémité, afin de
créer un joint d'étanchéité sur la première partie d'extrémité; et
un couvercle (53) configuré pour un perçage par des aiguilles et configuré pour porter
contre une surface extérieure de la première partie d'extrémité.
8. Capsule d'élution selon la revendication 7, dans laquelle le corps creux du premier
bouchon a une section transversale annulaire, et un diamètre extérieur (D12) de la
section transversale varie le long d'un axe du corps creux, et le couvercle a une
section transversale circulaire pleine, avec un diamètre extérieur (D15) supérieur
au diamètre intérieur de la première partie d'extrémité.
9. Capsule d'élution selon l'une quelconque des revendications précédentes, dans laquelle
la première rondelle a une section transversale annulaire, avec un diamètre extérieur
(D6) égal ou inférieur au premier diamètre intérieur de la première partie d'extrémité,
et la deuxième rondelle a une section transversale annulaire, avec un diamètre extérieur
(D8) égal ou inférieur au deuxième diamètre intérieur de la deuxième partie d'extrémité
10. Capsule d'élution selon l'une quelconque des revendications précédentes, dans laquelle
le tube est réalisé à partir d'au moins une matière parmi le zirconium de grande pureté,
l'aluminium, le verre et le quartz.
11. Capsule d'élution selon l'une quelconque des revendications précédentes, comprenant
en outre :
une première couche d'époxy située entre le premier bouchon et la première partie
d'extrémité, et une deuxième couche d'époxy située entre le deuxième bouchon et la
deuxième partie d'extrémité.
12. Capsule d'élution selon l'une quelconque des revendications précédentes, comprenant
en outre :
un premier joint d'étanchéité souple sur l'extérieur de la première partie d'extrémité,
et un deuxième joint d'étanchéité souple sur l'extérieur de la deuxième partie d'extrémité.
13. Capsule d'élution selon la revendication 12, comprenant en outre :
une première couche adhésive entre le premier joint d'étanchéité souple et la première
partie d'extrémité, et une deuxième couche adhésive entre le deuxième joint d'étanchéité
souple et la deuxième partie d'extrémité.
14. Procédé d'irradiation d'une matière dans une capsule d'élution (1), la capsule d'élution
comprenant un tube (10) avec une première partie d'extrémité (12) ayant un premier
diamètre intérieur, une deuxième partie d'extrémité (14) ayant un deuxième diamètre
intérieur, et une partie médiane (16) ayant un diamètre intérieur inférieur aux diamètres
intérieurs des première et deuxième parties d'extrémité, la partie médiane étant située
entre la première partie d'extrémité et la deuxième partie d'extrémité et étant configurée
pour contenir la matière; une interface entre la première partie d'extrémité et la
partie médiane formant un premier épaulement (100), et une interface entre la deuxième
partie d'extrémité et la partie médiane formant un deuxième épaulement (110); une
première rondelle (20) se trouvant à l'intérieur de la première partie d'extrémité,
en contact avec le premier épaulement; un premier filtre (30) se trouvant à l'intérieur
de la première partie d'extrémité, en contact avec la première rondelle; un deuxième
filtre (40) se trouvant à l'intérieur de la première partie d'extrémité, de manière
à ce que le premier filtre se trouve entre la première rondelle et le deuxième filtre;
un premier bouchon fermant de manière étanche la première partie d'extrémité; une
deuxième rondelle (60) se trouvant à l'intérieur de la deuxième partie d'extrémité,
en contact avec le deuxième épaulement; un troisième filtre (70) se trouvant à l'intérieur
de la deuxième partie d'extrémité, en contact avec la deuxième rondelle; un quatrième
filtre (80) se trouvant à l'intérieur de la deuxième partie d'extrémité, de manière
à ce que le troisième filtre se trouve entre la deuxième rondelle et le quatrième
filtre; et un deuxième bouchon fermant de manière étanche la deuxième partie d'extrémité,
le procédé comprenant :
la mise en place de la capsule d'élution, avec la matière se trouvant dans la partie
médiane de la capsule d'élution, dans une source de flux de neutrons, et
l'irradiation de la capsule et de la matière dans la source de flux de neutrons.
15. Procédé selon la revendication 14, selon lequel la matière comporte une substance
parmi le molybdate de titane, le molybdate de zirconium, le tungstate de titane et
le tungstate de zirconyle.