3. Measuring Cells
FlowStar2 LB 514
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3. Measuring Cells
A number of different Berthold measuring cells are available for radioactiv-
ity measurements in column eluates; all common sources can be meas-
ured with high efficiency with these cells. Depending on the measuring
method the cells are of different design (see Table 2).
3.1 Selection of Measuring Cells
Measuring cells are often distinguished according to the method of appli-
cation:
Heterogeneous method
: eluate and scintillator are separated (solid
scintillator). The eluate is completely available after the measurement
once it has passed through the cell.
Homogeneous admixture method:
the column eluate is mixed with liq-
uid scintillator and the resulting "cocktail" passed through the cell. After
having passed through the cell, the eluate is only available as a mixture.
For our purposes, we select a classification that is based on practical con-
siderations: on different applications and the resulting structure of the
measuring cells:
(a)
Cells with solid scintillator (YG, MX)
(b)
Homogeneous admixture method (Z)
(c)
Special methods for Gamma radiation (J and BGO)
(d)
Measurement of high-energy beta radiation using the Cerenkov effect
without scintillator (Z)
Identification of the cells
The cells are marked on their front plate by letters and numbers, which
have the following meaning and order: Example: YG-150 U 5 D
The first letter group identifies the cell type or the scintillator:
YG = Yttrium glass, Z = admixture cell, J = iodine,
BGO = external BGO scintillator, MX = MX scintillator.
The numbers indicate the cell volume in µl.
A possibly following letter indicates a surface treatment:
U = untreated, S = surface treatment
The following digit indicates the cell generation:
5 means 2"-photomultiplier counting chamber with cell ID chip starting with
device LB 513 in contrast to older series. The FlowStar
2
can only be used
with measuring cells of generation 5 and higher.
The last letter group identifies special applications:
P = preparative cells, D = cells with wire inside, M = cells for Micro-HPLC
with low dead-volume in- and outlets
Example:
Z-200 6M
means:
admix cell
,
volume 200 µl
,
type 6,
mircobore
.
YG
150
S
5
D
