&EPA
United States
Environmental Protection
Agency
Environmental Sciences Research
Laboratory
Research Triangle Park NC 27711
EPA-600/2-78-197
September 1978
Research and Development
Calibration Standards for
X-ray Spectrometers
Used for Pollution
Sample Analysis
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the ENVIRONMENTAL PROTECTION TECH-
NOLOGY series. This series describes research performed to develop and dem-
onstrate instrumentation, equipment, and methodology to repair or prevent en-
vironmental degradation from point and non-point sources of pollution. This work
provides the new or improved technology required for the control and treatment
of pollution sources to meet environmental quality standards.
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
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EPA-600/2-78-197
September 1978
CALIBRATION STANDARDS FOR X-RAY SPECTROMETERS
USED FOR POLLUTION SAMPLE ANALYSIS
by
Richard A. Semmler and Ronald G. Draftz
NT Research Institute
10 W. 35th St.
Chicago, Illinois 60616
Contract No. 68-02-173^
Project Officer
Roy Bennett
Emission Measurement and Characterization Division
Environmental Sciences Research Laboratory
Research Triangle Park, North Carolina 277H
ENVIRONMENTAL SCIENCES RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
RESEARCH TRIANGLE PARK, NORTH CAROLINA 27711
-------
DISCLAIMER
This report has been reviewed by the Environmental Sciences Research
Laboratory, U.S. Environmental Protection Agency, and approved for
publication. Approval does not signify that the contents necessarily
reflect the views and policies of the U.S. Environmental Protection Agency,
nor does mention of trade names or commercial products constitute
endorsement or recommendation for use.
i i
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ABSTRACT
A technique is described for making aerosol standards for x-ray
fluorescence analysis by depositing micron sized particles suspended in a
carrier solution onto the surface of a Nuclepore filter. Size is controlled
by a separate sedimentation step following grinding in a boron carbide
mortar and pestle. Binding of the deposition to the filter uses a collodion
film layer applied both before and after the particle deposition. The
deposited mass is determined gravimetrically from a companion filter prepared
from a large volume of carrier solution and without collodion. Standards
for 24 different elements have been prepared.
i i i
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CONTENTS
Abstract iii
Figures vi
Tables vii
Acknowledgments viii
1. Introduction 1
2. Recommendations and Conclusions 2
3. Procedure for Standards Preparation . 3
Preparing the suspension 3
Filtering and coating the filters ... 4
Mounting the completed filters 5
Packaging the completed filters 6
5. Development of a Preparation Technique 7
Preparation of suspensions 7
Filtering the suspensions 7
6. Completed Standards 12
Characterization of completed standards . 12
Materials selection and target values 27
References 33
Appendices
A. Self absorption in a sphere 34
B. Serial number lists 38
-------
FIGURES
Number
1 Filter apparatus for 20 mm and 35 mm deposits prepared 9
during Phase 1
2 Filter apparatus for 35mm.deposits prepared during Phase 2 . . 10
3 Probability of escape from a uniform spherical source as a
function of diameter/mean-free-path ... 28
4 Probability of escape from a uniform spherical source as a
function of diameter and mean free path 29
5 Geometry and notation used for describing escape of x-ray.
from within a spherical particle . 36
VI
-------
TABLES
Number Page
1 Calibration Data for Stock Suspension 13
2 Surface Density Calculation for Heaviest 35 mm Standard 15
3 Elemental Deposits on the Supplied Aerosol Standards 17
4 Analysis Data for .Compounds Used in Delivered Standards 19
5 Particle Size Data for Light Elements 24
6 X-ray .Characteristics for Elements and Compounds of Interest . . 25
7 Chemical Forms Selected for Use in Deposited Particulates .... 30
8 Desired Density and Other Data for Compounds of Interest .... 31
9 Desired Density and Other Data for Compounds of Interest .... 32
VI1
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ACKNOWLEDGMENTS
The invaluable assistance of Joe Puretz and George Yamate for the
laboratory work is gratefully appreciated.
Vlll
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SECTION 1
INTRODUCTION
The need for reliable calibration standards is often not appreciated
until considerable time and effort has been expended on instrument
development. X-Ray standards are no different and each investigator has
typically created his own special reference materials. This program to
prepare x-ray standards has concentrated on the development of a technique
which could be used with a variety of compounds to produce thin layers of
finely divided particles on the surface of the supporting substrate so that
particle size effects, interelement effects, and substrate absorption would
be minimal. The final technique which has been adopted is deposition of
previously sized particles from a suspension in isopropyl alcohol (IPA) onto
a Nuclepore filter plus a collodion film binder. Other binder techniques
have been attempted, in particular, softening of the Nuclepore filter, but
these have proved unreliable in practice. Details of the final procedure
are given in Section 3- A discussion of the evolution of the procedure is
given in Section 4.
Information on the specific compounds used for the standards is
collected within Section 5- This includes available information on purity,
gravimetric data on mass depositions, and comments on the effects of
particle size.
-------
SECTION 2
RECOMMENDATIONS AND CONCLUSIONS
f
A successful deposition technique for the preparation of thin aerosol
standards has been defined.
The essential steps include (1) grinding and sedimentation to control
particle size to 1 micron and under, (2) suspension of particles in isopropyl
alcohol, (3) filtration of a large volume of suspension to gravimetrically
determine deposition rate, (4) deposition of a collodion film on the
Nuclepore substrate prior to particle deposition, (5) particle deposition,
and (6) deposition of a second collodion film to complete the binding.
Essential details of the steps are described in other sections.
The problems encountered while developing the technique have been more
severe than anticipated, however, and the final procedure itself is more
complex and time consuming than the original estimates. Roughly, one should
allow a man-week of effort for the production of 1 set of standards, i.e.,
a total of 6 filters of one element with 2 deposition diameters and 3
different thicknesses. Proficiency and development of parallel processing may
eventually alter the time but experience has indicated that initially one
third of the time will be sent on grinding, sedimentation, sizing, and
calibration; one third of the time on dilution, deposition, and mounting
of the 35 mm deposits; and one third of the time on dilution, deposition,
and mounting of the 20 mm deposits. Any additional characterization such as
microscopic measurements on size and uniformity requires additional time.
While grinding and suspension of each new compound presents a new
situation and possible problems, the procedure is now relatively straight-
forward. Two areas for potential problems should be kept in mind, however.
One is the filter holder design. We have found variations in manufacture
of the supplied holders which cause wrinkling of the completed filter in the
process of closing the holder. This can ruin a standard after the investment
of considerable time and effort. The other area is compatibility with the
isopropyl alcohol used for suspension. If a change in liquids is required,
the deposition characteristics may be altered requiring a modification of the
procedure.
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SECTION 3
PROCEDURE FOR STANDARDS PREPARATION
The current procedure for producing calibration standards can best be
described by dividing the entire process into four parts:
A. Preparing the Suspension
B. Filtering and Coating the Filters
C. Mounting the Completed Filters in Permanent Retainers
D. Packaging the Completed Filters
The advantages and disadvantages of the current procedure and its
evaluation will be discussed in Section 4.
PREPARING THE SUSPENSION
Preparing suspensions involved essentially six (6) phases: (1) Micro-
scopical examination of pure materials, (2) grinding, (3) weighing^
(4) dispersal by sonification, (5) sedimentation, and (6) reweighing.
1. Powders are examined by optical microscopy to determine whether
the particle size is suitable for immediate filtration or whether
grinding is necessary.
2. When grinding is necessary, the powders are ground in a boron
carbide mortar and pestle for approximately 20 minutes and then
transferred to a clean vial.
3. One hundred milligrams (100 mg) of the ground sample is weighed
on an analytical balance and transferred to a clean 150 ml beaker.
Approximately 100 mis of I PA is added to the beaker.
k. The beaker containing the suspension is placed in an ultrasonic
bath for 20 minutes to break up weakly bound agglomerates. The
suspension is then cooled to room temperature and particles are
allowed to settle for 20 minutes. This cycle is repeated 3 or k
times to de-agglomerate the suspension as completely as possible.
-------
5. The suspension is then allowed to settle for 20 minutes to
remove the large particles. The fines are then carefully
decanted into a 1000 ml volumetric flask and brought to volume
with IPA. Most of the liquid is decanted leaving only the
obvious sediment at the bottom.
6. The coarse fraction is then filtered through a pre-weighed
Nuclepore membrane. After drying, the filter is reweighed.
The difference in weight between the original 100 mg and the
coarse fraction now on the filter gives the approximate weight
of fines.
FILTERING THE SUSPENSIONS
Filtering suspensions involved (1) dilution, (2) filtration apparatus
set-up, (3) filtration and coating, (4) drying, and (5) mass concentration
determination. The first four steps are performed in a clean bench.
*.
1. The approximate mass concentration of fines is used to estimate the
suspension volume required to produce depositions in the desired
range. Two different techniques were used to vary the mass being
deposited. In Method I, the fines are first diluted to produce
the suspension volume needed to produce the heaviest desired standard.
The second most concentrated standard is then prepared by diluting the
first suspension 1:10. The least concentrated standard is prepared
from a 1:10 dilution of the second suspension. The suspensions then
have a concentration ratio of 100:10:1. The same volume is used for
each suspension to prepare the standards, thus insuring uniform
precision. The Method I dilution technique was used during Phase 1
to prepare both the 20 mm and 30 mm standards, each size with 3
different concentrations (the 30 mm standard actually has a deposit
over a 35 mm diameter). The 20 mm standards were made using half the
volume of suspension used for the 30 mm standard. Subsequent doubts
about the trace solubility of so-called "insoluble" compounds led
to use of Method II which completely avoided multiple dilutions.
Method II was used during the second phase of the program when 6
different deposits were prepared for each compound using a 35 mm dia-
meter and no 20 mm standards were prepared. In Method II, the fines
are diluted to produce the total suspension volume needed for all
depositions with a concentration sufficiently dilute to permit use
of at least 5 ml of suspension for the smallest deposit.
2. ; The filter support and funnel are thoroughly cleaned with IPA
prior to filtration. The preparation of a 30 mm standard requires
an 0.8 ym Gelman membrane filter as an interface between the sintered
metal support plant and the 0.4 urn Nuclepore membrane which
receives the particles. The Gelman filter produces a more
uniform particle deposition. The two filters are rinsed in
clean IPA and carefully positioned concentrically on the filter
holder, Nuclepore on top, taking care that they are perfectly
flat with no sign of wrinkling. This is achieved by
-------
simultaneously wetting the filter with I PA and applying a slight
vacuum to the mounted filter. The same procedure is used for the
20 mm standard but no interfacial filter is required.
3- With a slight vacuum applied, the Nuclepore membrane is sprayed
with a nebulized mist of 5% commercial collodion in amyl acetate
from a DeVilbiss Glass Nebulizer AO. The vacuum is gradually
released and the filter funnel is carefully placed onto the
mounted filter and clamped into place. Some IPA is added to the
empty filter assembly and then gradually the suspension is rinsed
thoroughly and completely into the assembly. A watch glass is
placed over the funnel and vacuum is applied to the filter.
During this stage of the process it is important to control
the vacuum precisely, as too weak a vacuum will cause clogging
of the filter and too strong a vacuum may cause non-uniform
deposition, wrinkling or other problems. Occasionally, the
cover glass is removed and the funnel wall gently rinsed with
clean IPA to prevent sample loss, being careful not to disturb
the suspension. When the filtrate is gone, revealing the
substrate, the vacuum is made weaker, the clamp is removed and
the supper funnel is carefully lifted off. The filter is
checked visually under a magnifying glass for uniformity and
boundary sharpness. Vacuum is again applied and the filter
is sprayed with a nebulized mist of 0.1% solution of collodion
in amyl acetate.
k. The vacuum is released and the filter is placed on a flat
square of Teflon and left to dry under a large, clean glass
cover.
5. The exact mass concentration of fines is determined by filtering
a large volume of the most concentrated, suspension through a
pre-weighed Nuclepore membrane. The filter and residue are
dried and reweighed to determine the precise weight of standard
delivered to each filter standard.
MOUNTING THE COMPLETED FILTER
The filter holders supplied by the EPA (1) are comprised of two parts:
(1) the lower portion onto which the finished filter is placed and (2) the
upper retaining clip which holds the filter in place.
The completed filter is placed onto the bottom portion of the holder
and edge only is wetted carefully with a 0.11 collodion solution avoiding
the deposition entirely. The filter is then manipulated until it lies flat
and virtually wrinkle free on the holder.
Next a small crescent of Nuclepore membrane, onto which is printed
(in ink) the element name, concentration ratio and deposit area size, is
placed along the filter's edge, serving as a lavel. The retaining clip is
-------
compressed and placed over the filter and snapped into place in the bottom
holder. This assembly is then permitted to dry under a watch glass In the
clean hood.
PACKAGING OF COMPLETED FILTERS
Two clean 2" x 2" glass slides are assembled to form a sandwich into
which the standard is placed, thus serving to protect the upper and lower
surfaces of the filter.
DEPARTURES FROM STANDARD PROCEDURES
Certain compounds required special treatment. Such problems as
solubility in I PA and distortion of the Nuclepore filter had to be overcome.
Nad, Se02, As20. and KHCO, all proved to.be soluble in IPA. This
problem with NaCl was eliminatea by preparing a suspension using a
saturated solution of NaCl in water.
The use of other solvents such as acetone was precluded because it
distorted the Nuclepore fiIter.
-------
SECTION k
DEVELOPMENT OF A PREPARATION TECHNIQUE
Initially a procedure for the preparation of the standards was attempted
according to a different work plan. However, during the initial preparation
of filters, several unexpected problems arose. These problems and our
solutions to them are listed below.
PREPARATION OF SUSPENSIONS
Initially powders were selected on the basis of availability, purity,
and particle size according to the suppliers' specifications. Under optical
microscopy, however, it was determined that many more powders would require
grinding than was previously anticipated. The pure metal powders
particularly fell outside the claimed size range. Due to the difficulty of
grinding metal 1ic. powders alternate sample selections were generally made.
To avoid contamination In the grinding process a boron-carbide mortar
and pestle was used. These low atomic number elements give no interference
for x-ray fluorescence studies.
FILTERING THE SUSPENSIONS
Pilution
Early attempts at filter preparation involved the use of volumetric
pipettes rather than graduated cylinders. Pipettes seemed ideally suited
to the situation since small amounts of suspension could be withdrawn
accurately for the dilutions. However, upon further consideration it was
realized that pipettes could not accurately nor economically be used for
these dilutions.
Because only molecular "particle" sizes are encountered in a solution,
pipettes can be used accurately to deliver small quantities. However, in a
suspension, although mass concentration may be uniform, particle sizes are
orders of magnitude larger and certain difficulties arise.
A pipette is designed specifically so that the delivered volume is
correct when a small amount of liquid remains trapped in the bottom as
implied by the designation TD (to deliver). This type pipette should not be
blown out for accurate volume determination. Consequently, the pipette can-
not be rinsed into the filtrate to remove particles adhering to the walls.
-------
In order to avoid any cross contamination between suspensions, the
pipette had to undergo a thorough cleaning process involving detergent
rinsing, distilled water rinsing, acid bath and distilled water rinsing
again. The preparation of six filters per standard set and one additional
for mass determination rendering this method inaccurate and time consuming.
As an alternative, graduated cylinders were used with a small sacrifice
in accuracy but with significant advantages due to ease in cleaning, thereby
eliminating virtually all cross contamination in addition to the subsequent
saving of time.
Filtration System Set-Up
The Delrin funnel shown in Figure 1 was used for both 35 mm and 20 mm
standards (by inverting the funnel) when Method I was used to control mass
deposition. The Delrin funnel in Figure 2 holds the larger volume required
for the Method II procedure of controlling mass deposition.
As originally designed, the lower supports used specially fabricated
screens to support the filter under vacuum. After several filters were
prepared it was decided that they were unsatisfactory due to non-uniformity
of deposition and indistinct outer boundary. It was our intention to
produce a consistently uniform deposition with as sharp a boundary as
possible. To this end several modifications were made. A sintered metal
backing plate is used in the 35 mm support and the original support screen for
the 20 mm screen was modified to accommodate the screen in a slightly
recessed position.
In addition, for the 35 mm standard, it is necessary to use an 0.8 urn
Gelman filter underneath the Nuclepore membrane to assure a uniform filtration
surface and prevent the deposit from assuming the surface features of the
sintered metal backing plate. It took many attempts to finally find the
corrected method for obtaining a uniform deposit.
Filtration and Coating
Ideally, our intention was to produce a high quality standard whose
surface could be protected from dust and debris by a thin film which could
withstand gentle brushing with a soft brush. However, due to the require-
ment for a very thin film, so as not to cause appreciable beam attenuation, v
problems arose as to choice of film and method of application. Altogether,
four different methods of application were tried utilizing (l) colloidion
which is a film former, (2) polyvinylpyrrolidone (PVP) a film former, and
(3) the combination of collodion and PVP. Comments on the use of these
materials are as follows:
(1) Collodion mixed directly into the filtrate for simultaneous
deposition sometimes tended to clog the filter.
(2) Collodion of PVP dropped gently onto the substrate after
filtration destroyed the uniformity by forming spots.
-------
r-
1
I
1
\
I
\
\
\
\
i
I
l
1
1
1
1
1
1
^~-~~-
FILTERING FUNNEL
20 MM OPENING
^7 MM NUCLEPORE FILTER
20 MM STAINLESS STEEL SCREEN
FILTER HOLDER
TAP FOR 3/8-IN. TUBE TO SUCTION
Figure 1. Filter apparatus for 20 mm and 35 mm deposits prepared during
Phase 1
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- 3 3/4"-
•3"
3"
1 1/2"
\<
(^ 35 mm—^|
2 1/4°—
Figure 2. Filter apparatus for 35 mm deposits prepared during Phase 2
10
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An approximate calculation also showed the film to be
too thick.
(3) Collodion sprayed on the substrate only after filtration
was an improvement but did not provide adequate protection.
(b) The technique eventually selected involves a collodion spray
before and after the deposition and was described in
Section 3-
The theory behind this technique is that the first spraying with 5%
collodion solution deposits a thin film of collodion on the filter onto which
the particles will rest. The 0.]% collodion spray serves primarily to wet
the particles and bind them to the heavier collodion layer below the
particles.
The concentration of the first collodion spray is not crucial but it
cannot be so great as to clog the filter. On the other hand the second spray
concentration is important since it must meet the criterion of minimum x-ray
attenuation. Experimentation and rough calculation showed that our use of
a 0.1% collodion solution could not deposit more than a few hundreths of a
micron thick film. Since a thickness of 0.1 ym was acceptable, the film
thickness deposited was well within tolerable limits.
Mass Concentration
Mass concentration of fines was initially obtained using a Cahn Electro-
balance. The only problem has been the charging of the Nuclepore filters
which makes accurate weighing difficult. This persistent problem with
microbalance measurements was partially overcome using a Polonium-210
radiation source to discharge the membrane. However, this has not been
entirely successful and great care is required to make a good measurement.
The final procedure adopted is to filter a large volume of suspension and
weigh the residue on a semi-micro balance (+0.05 mg sensitivity). See
Section 5 for further details.
Mounting the Completed Filter
During the process of mounting the filters, there is a tendency for
them to wrinkle. This occurs because the upper retaining clip exerts
stresses on the filter and bottom holder which don't exist before the clip
is inserted. Apparently this difficulty cannot be surmounted with the
filter holders presently in use.
Packaging the Completed Filter
There is no problem associated with packaging the standards.
11
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SECTION 5
COMPLETED STANDARDS
A total of 2k standards have been prepared. These compounds are
Cr203, Mn02, RhO,, Fe20_, V205, Sb203, CaF2, AKO., As20o, Ti02, CuO, NiO,
BaSO/p Co Olj, PtO, ZnO, PdO, Sn02, Ag, Si02> Mo03? HgO, W03 and NaCl. The
calibration of these standards is purely gravimetric as described in the
next section.
CHARACTERIZATION OF COMPLETED STANDARDS
Mass
The correlation between deposited mass and volume of the suspension is
first determined by filtering and weighing a large (approximately 1000 ml)
volume and weighing the resulting deposit. This correlation is used for both
size standards since the same stock suspension is used throughout. Table 1
gives the gross and tare weights determined from multiple measurements of the
calibration deposit.
The volume of stock solution used for the heaviest deposit is tabulated
in Table 2 along with the resulting compound and elemental mass per unit
area. The larger deposition diameter is 35 mm. The surface density for the
20 mm deposit can be obtained from the 35 mm deposit with allowance for the
reduced area and the fact that only half as much solution is used for the 20
mm deposits.
Based on the deposits in Table 2, the reported mass values for the
filters of each size are given in Table 3-
The largest source of error is introduced by the dilutions and this
depends on the size of the graduate used and the number of dilutions. The
maximum error in a 35 mm deposit would be for Mn02 for which a 5 ml cylinder
was used for 3 measurements. This introduces, in conjunction with 2
measurements of 50 ml, an uncertainty of about 3.6% for the maximum dilution.
Dilution errors for other cases will be less.
Chemical Purity
Table 4 summarizes the available data on the chemical compounds used
for the standards.
12
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Table 1. CALIBRATION DATA FOR STOCK SUSPENSION
Compound
Group A
CaF2
A12°3
SiO,
AS2°3
TiO,
CuO
NiO
BaSO^
C°3°4
Pto2
ZnO
MoO.
Group B
PdO
Sn02
Ag
HgO
WO
NaCl
Cr2°3
Mn02
RhO,
Gross
Weight
.02211
.01756
.01524
.01438
.01600
.01478
.01598
.01868
.01485
.01835
.01675
.01723
.01694
.01622
.02442
. 01604
.01790
.01937
.05797
.03804
.05011
Tare
Weight
.01423
.01418
.01343
.01264
.01409
.01385
.01422
.01453
.01386
.01466
.01413
.01416
" .01421
.01421
.01386
.01428
.01464
-01394
.01362
.01378
.01401
Net Deposit, g
.00788
. 00338
.00181
.00174
.00191
.00093
.00176
. 0041 5
.00099
.00369
. 00262
.00307
.00273
.00201
.01056
-00176
.00326
.00543
.04434
.02426
.03610
Vo 1 ume
Filtered, ml
1000
1000
500
1000
1000
1000
1000
1000
500
1000
1000
1 GG-0
500
1000
1000
1000
1000
1000
500
500
400
13
-------
Table 1 (cont.)
Compound
Fe2°3
V2°5
Sb2o3
Gross
Weight
.02485
.01778
.02333
Tare
Weight
.01515
.01508
.01400
Net Deposit, g
.00970
.00270
.00933
Vo 1 ume
Fi 1 tered,
100
500
500
ml
-------
Table 2. SURFACE DENSITY CALCULATION FOR HEAVIEST 35 MM STANDARD
Compound
Group A
CaF2
A1203
Si02
As203
Ti02
CuO
NiO
BaSOit
Co30/,
Pt02
ZnO
Mo03
Group B
PdO
Sn02
Ag
HgO
wo3
NaCl
Cr203
Mn02
Suspension
Concentration,
mg/ml
0.00788
0.00338
0.00362
0.00174
0.00191
0.00093
0.00176
0.00415
0.00198
0.00369
0.00262
0.00307
0.00546
0.00201
0.01056
0.00176
0.00326
0.00543
0.08868
0.04851
Volume Used for Mass Delivered to
Heaviest 35 mm
Deposit, (ml)
500
500
500
500
500
500
500
500
500
500
500
500
500
500
500
500
500
500
10
5
Heaviest 35 mm
Depos i t , ug
3,940
1,690
1,810
870
955
465
880
2,075
990
1,845
1,310
1,535
2,730
1,005
5,280
880
1,630
2,715
886.8
242.6
Compound
Densi ty
409
176
188.1
90.4
99.3
48.3
91.5
215-7
102.9
191.8
136
159.6
283.8
104
549
91-5
. 169
282
92.2
25-2
Gravimetric
Factor
0.513
-------
Table 2 (cont.)
Suspension
Volume Used for
Concentration, Heaviest 35 mm
Compound
RhO,
Fe263
V205
Sb»0«
mg/ml
0.09024
0.09698
0.00540
0.01866
Deposit, (ml)
10
10
10
20
Mass Delivered to Compound
Heaviest 35 mm
Depos it, yg
902.4
969.8
54.0
373.2
Density
yg/cm2
93.8
100.8
5.61
38.8
Gravimetric
Factor
0.763
0.699
0.555
0.835
Elemental
Density,
yg/cm2
71 .6
70.5
3.12
32.4
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Table 3. ELEMENTAL DEPOSITS ON THE SUPPLIED AEROSOL STANDARDS
Compound
CaF2(Ca)
(F)
Al.O
^m ^
sio2
AS2°3
Ti02
CuO
NiO
Ba SO^Ba)
Co 0,
j *i
Pto2
ZnO
MoO-
Group B
PdO
Sn02
Ag
HgO
WO-
NaCl (Na)
(Cl)
Elemental
210 ,
199 ,
92.9,
87-9,
68.5,
59.6,
38.6,
71-9,
127 ,
75.5,
165 ,
109 ,
106 ,
247 ,
82.3,
549 ,
84.7,
134 ,
111 ,
171 ,
Mass on the 35 rnm
105
99
46
43
34
29
19
35
63
37
82
54
53
123
41
274
42
67
55
85
9
.5,
.5,
-9,
.2,
.8,
.3,
.9,
.4,
• 8,
.4,
.7,
.2,
,
.2,
,
• 3,
.2,
-5,
.6,
21
19
9
8
6
5
3
7
12
7
16
10
10
24
8
54
8
13
11
17
.0 ,
.9 ,
.29,
.79,
.85,
-96,
.86 ,
.19,
.7 ,
.55,
.5 ,
• 9 ,
.6 ,
-7 ,
.23,
.9 ,
.47,
.4 ,
.1 ,
.1 ,
10.
9.
4.
4.
3.
2.
1.
3.
6.
3.
8.
5.
5.
12.
4.
27.
4.
6.
5.
8.
Depos i ts ,
5 ,
95,
65,
39,
42,
98,
93,
59,
34,
78,
24,
47,
32,
3 ,
12,
4 ,1
23,
72,
55,
56,
4
3
1
1
1
1
0
1
2
1
3
2
2
4
1
1
1
2
2
3
.20 ,
.98 ,
.86 ,
• 76 ,
• 37 ,
.19 ,
.772,
-44 ,
.54 ,
.51 ,
.29 ,
• 19 ,
.13 ,
.94 ,
.65 ,
,0 ,
.69 ,
.69 ,
.22 ,
.43 ,
. 2
yg/cm
2
1
0
0
0
0
0
0
1
0
1
1
1
2
0
5
0
1
1
1
.10
• 99
.929
.879
.685
.596
.386
.719
.27
.755
.65
.09
.06
.47
.823
.49
.847
.34
.11
.71
17
-------
Table 3 (Cont'd)
Elemental Mass Density „ Elemental Mass Density „
Compound on the 35 mm Deposits, g/cm on the 20 mm Deposits, g/cm
Cr203 63.1 , 6.31 , 0.631, 96.6 , 9-66 , 0.966
Mn02 15.9 , 1.59 , 0.159, 24.4 , 2.44 , 0:244
Rh02 71.6 , 7-16 , 0.716, 109-6 , 10.96 , 1.096
Fe203 70.5 , 7-05 , 0.705, 107-9 , 10.79 , 1.079
V2°5 3.12, 0.312, 0.312, 4.77, 0.47.7, 0.0477
Sb0 32.4 , 3.24 , 0.324, 49-6 , 4.96 , .496
18
-------
Table 4. ANALYSIS DATA .FOR COMPOUNDS USED IN DELIVERED STANDARDS
Compound Supplier
CaF. Spex
Al-0, Johnson-Matthay (JMC) 345
^ J
SiO, JMC 425
£i
As00, JMC 642
2 3
Ti00 JMC 435
2
CuO JMC 40
NiO JMC 895
BaSO. Spex
Lot No. Analysis Data
99.999S5
S.52652E Si 3 Ppm
Ca 2
Fe 2
Mg 1
Cr <1
Cu <1
S. 53797 Ca 3 Ppm
Fe 2
Mg <1
Ag <1
S.52136C Sb 6
Si 2
Fe 1
Cu <1
Mg <1
S. 52138B Si 5
Na 2
Mg <1
S.52378A Bi 6
Si 1
B <1
Cd <1
Ca <1
Fe <1
Mg <1
Ag <1
S.53375/b Al 3
Bi 3
Si 3
Ca <1
Cr <1
Cu <1
Fe <1
Mg <1
10741 Ba 57-5%
Mg 1-5 ppm
Si 1-5
Ca 0.5-2
Na 0.5-2
Fe 0.5-2
19
-------
Table 4 (cont.)
Compound Supplier
Co.O. JMC 875
3 4
PtO- Research Organic/Inorganic
ZnO JMC 155
MoO. JMC
PdO Spex
SnO JMC
HgO JMC 191
Lot No. Analysis Data
S. 5095 ID 1 Si 7 ppm
Ni 5
Fe 2
Al <1
Ca <1
Cu <1
Mg <1
Ag <1
99-9%
S.52971B Fe 3 ppm
Cd 2
Mg 2
Si 1
Ca <1
Cu <1
Mn <1
Na <1
S. 52534 Mg 5 ppm
Cu 3
Fe 3
Ca <1
Si <1
11741 Fe 5-20 ppm
Sn 5-20
pd 87-9%
pt 10-30 ppm
Si 10-30
Bi 5-20
Pb 5-20
Mg 5-20
S53523C C Si 10 ppm
Ca 3
Al 1
Mg <1
Na <1
S 53625 Si 7
Cr 2
Cd 1
Cu <1
Mg <1
Ag <1
20
-------
Table k (cont.)
Compound Suppl ier
Ag Aremco Prod.
WO. JMC
Sb20 Spex
Cr20 JMC 705
Fe20- Pfizer
Mn02 JMC 815
Rh02 Spex
Lot No.
Analysis Data
99-9%
S.5M34D Mo 1
Mg <1
077^1 Sb 82.2%
Si 2-5 ppm
Mg 0.5-1 ppm
Cu 0.5-1
Fe 0.5-1
Bi 0.5-1
S.51597F Si 4 ppm
Na 3
Cu <1
Mg <1
R3098R ' Fe20 99-5%
Lot 55 Si 62 200 ppm
CaO 110
MgO 50
Na 50
In 70
Mn 660
Pb 12
As <1
Hg <0.1
Water soluble
salts 0.0k%
S.51800A Si 5 ppm
Mg 2
Ca 1
Cu 1
10691 Ni 50-100 ppm
Pt 5-20
Pd 5-20
Fe 1-5
Mg 1-5
Cu 1-5
Pb 1-5
Ru 5-20
21
-------
Table k (cont.)
Compound
V2°5
Supplier
JMC
Lot No.
S53459B
Al
Ca
Cu
Fe
Mg
Si
Analysis Data
1 ppm
22
-------
Size and Uniformity
Visual inspection of the completed standards by optical microscopy
indicated most particles were 1 micron or under in size. An occasional larger
particle, probably an agglomeration of smaller particles, up to 10 micron
can be seen. The particle distribution presents a visually uniform
appearance.
Initially, an analysis of size and uniformity was planned using an
electronic image analyzer. The confused image created by the numerous
pores in the Nuclepore filter, however, has prevented using this quick but
quantitative technique. Data from visual microscopy are given in Table 5.
X-Ray Characterization
The x-ray absorption characteristics for all the compounds of interest ,
are given in Table 6. This includes the absorption coefficient and the mean
free path for the fluorescent x-rays in the specified compound. Most of the
data are for the K lines but data for L and M lines is included if these
are likely to be used.
Particle Size Effects
In thin deposits such as these standards, allowance for the effect of
particle size on response depends on the x-ray absorption characteristics,
i.e., self-shielding properties, of the particles. For a complete des-
cription of the effect, the energy distribution of both the incident and
emitted x-rays as well as the typical geometry of the particle must be well
specified. In practice, the particle geometry is often poorly or only
approximately determined.
If information on the approximate particle size is available, one can
estimate the expected effects using formulas such as reviewed in
Reference (2).
Alternatively, one can determine the effective particle size by making
two separate fluorescence measurements on each sample using two different
energies of excitation radiation (3). Since the sample mass is the same
in both cases, any observed difference in response can generally be
ascribed to particle size effects. Corrections for the effect can then be
made.
A first order estimate of the significance of particle size or self
shielding effects can be made by comparing the particle diameter with the
radiation mean free path. A large ratio of diameter to mean free path
obviously implies significant self absorption within the sample.
The approximate losses can be put on a quantitative basis by calculating
the fraction of x-rays escaping from a spherical particle, (radius = R),
with x-rays generated uniformly throughout the volume. This assumes
23
-------
Table 5. PARTICLE SIZE DATA FOR LIGHT ELEMENTS
Compound
CaF,
2
BaSO,
T
MoO,
J
NaCl
Al 0
*- J
Size Range
<2 ym
2-5
5-10
>10
<2 ym
2-5
5-10
>10
<2 ym
2-5
5-10
>10
<5-3 ym
5.3-15-9
15.9-26.5
26.5-53
>53
<5.3 ym
5.3-10.6
10.6-21.2
>21.2
Number
of Particles
185
293
39
3
520
37
291
69
3
400
177
227
10
2
416
71
146
135
120
31
503
238
156
33
6
Number
Percent
35. 6£
56.3
7-5
0.6
100.0%
9.22
72.8
17.2
0.8
100.0%
42.5%
54.6
2.4
.5
100.0%
14.1%
29.0
26.8
23.9
6.2
100.0%
55.0%
36.0
7-6
1.4
433 100.0%
24
-------
Table 6
X-RAY CHARACTERISTICS FOR ELEMENTS AND COMPOUNDS OF INTEREST
(E = X-Ray Energy, p - Mass Absorption Coefficient, and A = X-Ray Mean Free Path)
Element
Al
Sb
As
Ba
Br
Ca
Cd
Cl
Cr
Co
Cu
Au
F
Fe
Pb
Mg
Mn
Compound
Al
A12°3
Sb2°3
AS2Q3
BaC03
BaSO,
4
PbBr2
NaBr
RbBr
CaCO
Ca(OH)2
CdO
LiCl
Cr
Cr 0
2 3
Co
C°3°4
Cu
CuO
Au2°3
LiF
Fe
Fe2°3
Pb
Pb02
Pb3°4
Mg
MgF
MgO
Mn02
MnCO_
Density
gin/cm-^
2.702
3.965
5.2
3.738
4.43
4.50
6.66
3.203
3.35
2.710
2.24
6.95
2.068
7.20
5.21
8.9
6.07
8.92
6.4
it
2.635
7.86
5.24
11.34
9.375
9.1
1.74
*
3.58
5.026
3.125
Line
Al
Al
As
Br
Br
Br
Ca
Ca
Cl
Cr
Cr
Co
Co
Cu
Cu
Ka
Ka
-
Ka
-
-
Ka
Ka
Ka
Ka
Ka
-
Ka
Ka
Ka
Ka
Ka
Ka
Ka
-
F Ka
Fe
Fe
Mg
Mg
Mg
Mn
Mn
Ka
Ka
-
Ka
. Ka
Ka
Ka
Ka
1
1
10
11
11
11
3
3
2
5
5
6
6
8
8
0
6
6
1
1
1
5
5
E
keV
.487
.487
.53
.91
.91
.91
.691
.691
.622
.412
.412
.926
.926
.040
.040
.679
.401
.401
.254
.254
.254
.895
.895
U
X
cm /gm
385.
912.
30.
62.
27.
35.
.116.
125.
175.
88.
72.
64.
52.
53.
45.
832.
7
1
1
0
2
0
4
4
1
2
8
9
8
7
5
2
71.4
57.
463.
2051.
1245.
61.
52.
3
6
1
4
6
1
Micron
9.
2.
88.
24.
114.
85.
31.
35.
27.
15.
26.
17.
31.
20.
34.
4.
17.
33.
12.
*
2.
32.
60
77
9
2
8.
3
7
6
6
7
4
3
2
9
3
56
8
3
4
24
3
E 2V X E 2y X
Line keV cm /gm Micron Line keV cm /gm Micron
-
-
Sb Lai 3.605 365.6 5.26
As Lai 1.282 1737.6 1.54
Ba Lai 4.465 239.5 9.43
Ba Lai 4.465 265.3 8.38
Br Lai 1.480 2103.6 0.714
Br Lai 1.480 1759.4 1.77
Br Lai 1.480 1413.8 .2.11
-
-
Cd Lai 3.133 453.0 3.18
-
.-
_
-
-
-
-
Au Lai 9.712 114'.4 * Au Ma 2.12 1068.1 *
-
-
-
Pb Lai 10.55 116.6 7.56 Pb Ka 2.342 983.0 .897
Pb Lai. 10.55 98.5 10.83 Pb Ma 2.342 890.0 1.20
Pb Lai 10.55 106.3 10.3 Pb Ma 2.342 930.2 1.18
-
-
-
-
61.4
-------
Table 6 (cont.)
M
Density
Element Compound era/cm3
Hg
Mo
Ni
Pd
P
Pt
K
Rh
• Se
Si
Ag
Na
S
Sn
Ti
W
U'
V
Zn
_ _, -f- T „
HgO
Mo
Mo03
MoS2
Ni
NiO
PdO
P3N5
Pto2
KHC03
KN03
Rh02
Se02
Si02
Ag
Ag20
Na2SO,
Na2C03
S
(NH ) SO
Sn
SnO.
Ti02
W
wo3
U3°8
V2°5
Zn
ZnO
_^__ »~t • i —
11.1
10.2
4.692
4.80
8.90
6.67
8.70
*
10.2
2.17
2.109
*
3.95
2.65
10.5
7.143
2.68
2.532
1.92
1.769
ft
7.28
6.95
4.26
19.35
7.16
8.3
3.357
7.14
5.606
Line
_
Mo Ka
Mo Ka
Mo Ka
Ni Ka
Ni Ka
-
P Ka
-
K Ka
K Ka
-
Se Ka
Si Ka
-
-
Na Ka
Na Ka
S Ka
S Ka
-
-
Ti Ka
-
-
-
V Ka
Zn Ka
Zn Ka
E
keV
17.46
17.46
17.46
7.473
7.473
2.014
3.313
3.313
11.21
1.740
1.041
1.041
2.307
2.307
4.512
4.951
8.631
8.631
U
2
19.1
13.2
15.65
58.9
49.7
322.2
143.9
148.5
26.2
667.8
2565.8
2349.6
239.4
323.6
92.6
77.3
49.0
41.4
X
Micron
51.
161.
133.
19.
30.
*
32.
31.
96.
5.
1.
1.
21.
17.
25.
38.
28.
43.
3
.5
1
1
2
0
9
6
65
45
68
8
5
4
5
6
1
Line
Hg Lai
Mo Lai
Mo Lai
Mo Lai
-
-
Pd Lai
-
Pt Lai
-
-
Rh Lai
Se Lai
-
Ag Lai
Ag Lai
-
-
-
-
Sn Lai
Sn Lai
-
W Lai
W Lai
U Lai
-
-
.
E
keV
9.987
2.293
2.293
2.293
2.838
9.441
2.696
1.379
2.984
2.984
3.443
3.443
8.396
8.396
13.612
2 X
cm /gm Micron
115.1 7.83
728 1.35
633.1 3.37
533.7 3.90
514.9 2.23
114.4 8.57
519.1 *
1543.4 1.64
521.9 1.82
500.4 2.80
437.4 3.14
374.5 3.84
150.8 3.43
121,9 11.5
80.7 14.9
E „ X
Line keV cm /gm Micron
Hg Ma 2.195 1043.2
-
-
-
-
-
-
-
Pt Ma 2.048 1109.6 0.884
-
-
-
-
-
-
-
-
-
-
-
-
-
-
W Ma 1.774 1465.6 0.353
W Ma 1.774 1351.0 1.03
U Ma 3.165 615.0 1.96
-
-
-------
negligible attenuation of the stimulating radiation within individual
particles. The fraction, f, of x-rays which escape in any given direction
is given by (see Appendix):
f ^ _J_^ (l-e~2ER)(l+ER)
(ER)Z 2(ER)3
where E is the macroscopic x-ray absorption cross section (= 1/mean-free-
path). Figure 3 is a plot of f versus the size parameter D/A, where
D= diameter and X = mean free path.
An alternative way to plot the same equation is given in Figure k.
Explicit values of the mean free path, A, such as given for the calibration
standards, can be used to enter the graph. The emission rate for different
size spherical particles can then be read out directly.
Generally, if the emission is to be greater than 90% for 1 micron
particles, then the mean free path should be greater than 4-7 micron.
The tabulated values for the mean free path In the standards provided
indicate that they are all greater than 5 micron except for AKO , PbO, SnCL,
Ag and MoO^. Losses should therefore be less than 10% for the deposits
since they are generally under 1 micron in size.
MATERIALS SELECTION AND TARGET VALUES
Catalogs from about 100 chemical supply houses were examined to
determine sources of material. The initial list of possible compounds was
based on chemical simplicity, purity available, particle size, certification,
etc. A second list of simple compounds which are likely to be present in
aerosol samples was also prepared as a useful alternative compound. The
initial screening of these lists produced a list which contained generally
acceptable compounds. Table 7 contains the list of chemical forms finally
selected for deposition.
The formula weights, gravimetric factors, and desired surface density
for each of these compounds is given in Tables 8 and 9.
^Density not available.
27
-------
ho
oo
0.8 -
0.6 -
o
o
V
Q.
UJ
1 I I I 1 1 I 1 I
0.4 -
0.2 -
0.01
Figure 3-
Diameter/ Mean-Free-Path D/X
Probability of escape from a uniform spherical source as a
function of diameter/mean-free path
100
-------
WO
§
u
2E
£
o
5
0.01
Q!
10
Mean Free Path X (Micron)
100
1000
Figure ^». Probability of escape from a uniform spherical source
as a function of diameter and mean-free-path
-------
Table 7. CHEMICAL FORMS SELECTED FOR USE
AS DEPOSITED PARTICULATES
Element
F
Na
Mg
Al
Si
P
S
Cl
K
Ca
Ti
V
Cr
Mn
Fe
Co
Ni
Cu
Forms
LiF
Na2CO
MgO, Mg, MgF2
A120 , Al
SiO,
P3N5
S, (NHit)2SOil
LiCl
KHCO-, KNO_
CaCO , Ca(OH)2
. Ti02
V2°5
Cr, Cr20_ .
MnCO,, Mn02
Pp Ppa A
1 C J 1 CM V A
Co, Co^
Ni, NiO
Cu, CuO
E1emen t
Zn
As
Se
Br
Mo
.Rh
Pd
Ag
Cd
Sn
Sb
Ba
W
Pt
Au
Hg
Pb
U
Forms
Zn, ZnO
Se02
PbB>2> NaBr, RbBr
Mo, MoO
Rh02
PdO
Ag20
CdO
Sn, SnO
Sb2o3
BaCO.
W, WO.
PtCL
HgO
Pb, PbO,
U3°8
3
30
-------
Table 8
ARF FIITFK
DESIRED DENSITY AND OTHER DATA FOR COMPOUNDS OF INTEREST
Fl ! HINT
SO UG 1 IT
AL
SI-
AS
R'
BR
Cfl
CD
Cl
CR
CR
CO
cu
AH
F
Ft
PS
HC
MN
HC
MO
Ml
PD
p
pr
K
RM
sr.
ii
(. ,
•i£
-,-••
r ,
V
IH
;N
FORHLILA
AL
AL203
SII203
AS203
B1C03
BAS04
PBBR2
NABR
RBB»
C«C03
CA(OH)2
cno
LICI
CR
CR203
CO
C0304
CU
cuo
AU203
LIF
F,
FE203
PI'
PB02
pp.3.04
Mi.
MCF7
MGO
MN02
MNC03
Ht.O
MO
M001
MOS2
Ml
NIO
P! 0
P SN5
PIO'
KHC03
KN01
Rl'02
sr o>
5IO,>
Al.
AG.-'O
N''.' S04
N/-7COJ
S
(Mil , >,'S04
N/1-/ Si)-,
•>:i
srm.
1 1 0 '
J
w.
•'
v>0',
'.U
/NO
FORMULA
WEIGHT
26.982
101.960
291.500
197.840
197.390
233.400
367.010
102.900
165.380
100.1190
74.094
128.400
42.392
51.996
15 1 .990
58.933
240.800
63.540
79.539
441.930
25.937
55.847
159.690
207.190
239.190
685.570
24.312
62.308
40.311
86.936
114.950
216.590
.95*1)40
143.940
160.070
58.710
74. /09
122.400
162.960
227.090
100.120
101*110
134.900
110.960
60.084
107.8/0
231.740
142.042
105.990
32.064
132.140
147.04?
1 1 R.690
! ^0»6">0
79.1: (•
'Ml. ',!l
! .
•i • .
im. no
65.370
81.169
ELEMENT
WEIGHT
26.982
93.464
243.900
149.840
137.340
137.340
199.820
79.909
79.904
40.080
40.080
112.400
39.493
51.996
103.990
58.933
176.799
63.940
63.540
393.<<30
18.998
55.847
111.640
207.190
207.190
621.570
24.312
24.312
24.312
54.938
94.938
200.590
95.')40
95., 140
95.940
58.710
58.710
106.400
92.0J2
195.090
39.102
39.102
102.905
78.960
28.0116
107.810
215.740
45.982
45.982
32.064
32.064
1,? .'164
i i n • i , 9 1
' 1 H . 1 <> 1
',7. "01
I s
- 1-00.1,80
6.5.370
65.170
USING .90 OF VOL. COMPOUND MASS
GRAVIMETRIC RESULTING ELEMENT (UG) ON SMALL
FACTOR
1.000
0.924
0.835
0.797
0.646
0.588
0.435
0.777
0.413
0.400
0.941
0.875
0.836
1.000
0.684
1.000
0.734
1.000
0.749
0.891
0.732
1.000
0.699
1.000
0.866
0.907
l.OOO
0.390
0.603
0.632
0.478
0.926
1.000
0.667
0.599
1.000
0.786
0.869-
0.570
0.859
0.391
0.387
0.763
0.712
0.467
1.000
0.931
0.324
0.434
1.000
0.2'.!
0.?26
1 .0 0
.76 «
.6 0
.0 :•!
..'•'!
'' "''.
.555
1 .0' U
• a i
OBNIITY
0.04W
0.0499
0.7656
4.9«3*
O.T696
0.76*6
0.7*16
0.7656
0.7616
0.7656
0.7656
0.0766
O.T696
0.7696
0.7656
0.7696
0.7696
0.7616
0.76)6
0.7656
0.7656
0.7656
0.7696
0.4994
0.4594
0.4594
0.7696
0.7656
0.7696
0.4944
0.4994
0.7696
0.7696
0.7656
0.7656
0.7656
0.7656
0.7656
0.1531
0.7656
O.0459
0.0459
0.7696
0.7656
0.153)
0.7656
0.7656
1.5312
1.5312
0.1531
0.1531
0.153
1. 76r>6
0.7656
••76",6
-. 7//',/
1 . . 6-i<
'•"' '''-
0.7.656
0.7656
0.7656
ttw/iacH) « i uor*i«e*
0.45*
0.454
7.656
41.937
7.616
7.616
7.656
7.656
7.696
7.696
7.656
0.766
7.696
7.656
7.656
7.696
7.696
7.696
7.696
7.696
7.656
7.656
7.656
4.944
4.594
4.594
7.656
7.656
7.656
4.594
4.594
7.656
7.656
7.656
7.656
7.656
7.656
7.656
1.531
7.656
0.454
0.459
7.656
7.656
1.531
7.656
7.656
15.312
15.312
1.531
1.531
1 .531
7. ,.',6
/..Ah
' . ' '^ 6
~ . • >, f
'. •>(,
• '•'•
7.656
7tf>56
7.^.56
Sit*
76.16
153.13
76.lt :
76.96
76.96 <
74.96
76.96
76.56
•76.96
7.66
76.16
76.56
76.56
76.96
76.96
76.16
76.96
76.56
76.56
76.56
76.56.
45.94
49.94
45.94
76.56
76.56
76.56
45.44
45.44
76.56
76.56
76.56
76'.56
76.56
76.56
76.56 '
15.31
76.56
4.99
4.59
76.96
.416
.761
.148
• II*
.334
.214
.Ml
.102
.84!
.BOB
.589
.716
.142
.142
.142
.27.4
.142
.433
.524
.2*4
.142
.4*2
.142
.627
.465
.142
.051
.209
.971
.573
.392
.142
.713
• 242
.142
.448
.614
.510
.657
.044
.124
.118
76. 56 4.415
15.31 6.721
76.56 3.142
76.56 3.375
1S3.13 4.705
153.1! 7.241
15.31 3.142
15.31 12.947
t'i.31 11.917
V6.1 3.142 .
76. '' i.98<)
76. *> >.240
V,.,1; . 3. 14.'
. .'- l.af ••
' .-. ' 3.7-)',
76.5 5.664
76.5. 3.142
76.5 3.910
TOTAL COMPOUND MASS
(UOI WITHIN SMALL AREA
AT RESULTING DENSITY
0.144
0.273
2.879
19.019
3.496
4.088
5.123
3.047
.4.478
6.007
4.447
0.279
2.876
2.409
3.516
2.409
3.276
2.409
3.011
2.698
3.284
2.405
3.439
1.443
1.666
1.592
2.405
6.164
3.988
2.284
3.020
2.997
2.405
3.609
4.013
2.405
3.061
2.767
0.844
2.800
0.370
0.373
3.153
3.380
1.029
2.405
2.584
14.860
11.089
0.481
1.983
2 . U 1
.•-.',,15
' .o-,4
., .01. >
. • )r>
', . <
.i ^ 1,
.',.337
2.405
2.994
1.44
2.73
28.74
140.91
34.96
40.68
55.23
30.47
49.76
60.07
44.47
2.79
28.76
24.09
39.16
24.05
32.76
24.05
30.11
26.98
32.84
24.05
34.39
14.43
16.66
15.92
24.05
61.64
39.88
22.84
30.20
25.97
24.05
36.09
40.13
24.09
30.61
27.67
8.44
28.00
3.70
3.73
31.93
33.80
10.29
24.05
25.84
148.60
110.89
',.81
19.83
2' .3
2'. .05
4 • . 1 .'
,-, , 1^
t •
> . w
4', .37
24.05
14.4
27.3
287.9
635.2
349.6
408. 6
552.3
109.7
447.8
600.7
444.7
27.5
287.6
240.5
351.6
240.5
327.6
240.5
301.1
269.8
328.4
240.5
343*9
144.3
166.6
159.2
240.5
616.4
398.8
228.4
302.0
259.7
240.5
360.9
401.3
240.5
306.1
276.7
84.4
280.0
37.0
37.1
315.3
338.0
102.9
240.5
25f).4
1486.0
1100.9
19IS.3
211.
?', -. ',
M-..4
4.1-.,'
•-. ., . .
.
' ••
4.3 1 . 7
240.5
299.4
THICKEST
COMPOUND
(UG/5QCM)
4.14
9.611
91.65
202.18
110.02
130.11
171.82
98.59
158.45
191.20
141.54
8.75
91.55
76.56
111.90
76.56
104.28
76.56
95.84
85.1-9
104.53
76.^1
109.47
45.94
53.03
50.67
76.56
196.22
126.95
72.69
96*12
82*67
76.5..
114.87
127.74
76.56
97.43
88*0"
26*85
119* 12
1 1 .76
11.88
100.37
107.59
32-76
76.5-
82*24
473 .02
352.96
15.11
63.10
67 -H '.
7 6 « '
' ' 7 • " 1
i
1 .
1 >8 . 04
76 . ','
-------
L/ KG! ARC I II TEI
Table 9
E7~ DESIRED DENSITY AND OTHER DATA FOR COMPOUNDS OF INTEREST
ro
Fl I Ml NT
SOUGHT FORMULA
Al
SI
AS
B'
BR
C.«
CD
CL
CR
C»
CO
CU
flu
r
fp
pp
M(
MM
Hf.
MO
Nl
PP
P
pr
K
RM
sr
SI
AC
NA
',
SN
TI
•4
II
V
ill
ZN
Al
Al 203
S. 201
A',203
BAC03
BAS04
PBBR2
NABR
RBBR
C/iCOl
CA ( OH 1 2
ciio
LICL
ci;
CR203
CO
Q0304
en
cuo
A1I203
LIF
f>
FE203
PP
PP02
PP304
M(
MGP2
MGO
MM02
MNC03
nro
MO
M003
M052
Nl
NIO
fr.O
P3N5
PI02
KHC03
KNOT
RN02
Sr02
S 102
A'
AC20
N "•? S04
NA2C03
S
INH4 l.'SO'i
NJVSIJ4
SM
SNOJ
rici '
w
<*c
u »•
V:>0',
^M
•/MO
FORMULA
WEIGHT
26.982
101.960
291.500
197.840
197.390
233.400
367.010
102.900
165.380
100.090
74.094
128.400
42.392
51.996
151.990
58.033
240.800
63.540
79.539
441.030
25.937
55.847
159.600
207.190
239.190
685.570
24.312
62.308
, 40.311
86.936
114.050
216.590
95 .^)40
143.940
160.070
58.710
74 . , 09
122.400
162.960
227.090
100.120
101.1 10
134.900
110.960
60.084
107.8,0
231.740
142.042
105,990
32.064
132.140
142.042
1 18.6QO
1'50. h'lO
79.11. 8
. 1 !l3. '.1
' * 1 - ' •
- ' '• !"
iKl. ftj
65 - 1 70.
n 1.360
ELEMENT
WEIGHT
26.912
S3. 964
243.500
149.840
117.1140
137.340
159.820
74.909
79.909
40.080
40.080
112.400
35.453
51.996
103.990
58.933
176.Y99
63.540
63.540
393.') 30
18.098
55.847
111.690
207.190
207.190
621.570
24.312
24.312
24.312
54.038
54.938
200.590
05. )40
05.V40
95.1:40
58.710
S8.710
106.400
02. "22
195.090
39.102
39. .102
1O2.005
78.060
28.11116
107. RVO
215.740
45.982
45.082
32.064
12.064
32. '64
( Ifl.f.QO
118, f>0(l
47.QOO
( . r "
, 1, V
; ' ., • ij
100.il Hi
••1,5. 1711
65, 570
COMPOUND MA 8 8
GRAVIMETRIC DEI I RED tLEMINT 2f>
1 .O'"0
,78fl
,6 0
1 .0 0
.751
. M-lfl
.555
•l.O'.O
. S 1
O.O300 0.3OO
0.0)00 O.SOO
O.SOOO 9.000
3.0000 50.000
0.1000
0.1000
o.sooo
0.5000
o.sooo
o.sobo
o.sooo
0.0500
0.5000
o.sooo
o.sooo
o.sooo
o.sooo
o.sooo
o.sooo
o.sooo
0.9000
0.9000
o.sooo
0.3.000
0.3000
0.31)00
0.5 100
0.5000
.000
•000
.000
.000
.000
.000
.000
.500
.000
.000
.000
.000
.000
.000
.000
.000
,000
,000
.000
.000
.000
.000
.000
.000
O.SOOO 5.000
0.3000 3.00O
0.3000 3.0OO
O.SOOO 5.000
0.5000 5.000
O.SOOO 5.000
O.SOOO 5.000
0.5000 5.000
O.SOOO 5.000
0.5000 5.000
0.1 1)00 1.000
0.5000 5.000
0.0300 0.-300
0.0300 0.3 0
0.5000 5.000
0.5000 5.000
0.1 000 1.000
0.5000 5.000
0.5.00 5.000
1.0000 10.0 0
1.0000 10.0 0
o.i oo 1.010
O.I 00 l.'MO
0.1 00 I.O.JO
"1.5 00 5, ''10.
0.5 -00 5." n
1.5 00 5, 'HI
'-.r, m •>. ' ,-,
,).'- -P) <-,. MI
1,' '1 l • , :
D.'I.OO 5.0,0
1 •« 5.i 00 5 . l ' 10
0.5 >Qi) 5,,'iOO
3.00
3.00 '
90.00
100. on
SO. 00
so.oo
so.oo
90,00
so.oo
90.00
90.00
5.00
90.00
90.01)
so.oo
50.00
so.oo
90.00
90.00
90.00
90.0')
SO.OO
50.00
30.00
30.00
30.00
50.00
SO.OO
50.00
30.0(1
30.00
SO.OO
50.00
50.00
90.00
50.00
So.oo
sn.Oii
10.0 )
50.00
3.00
3.00
50.00
50,0.1
10. On
50.0
50 , 0'fl
100,'! )
100. '1 '
10.0
1 ,.!>
1 ,1)
5, '.il
5 •• ) :
5' -,'J
5 .C
r,
'•.-••
5 i.'n
.Sii.O
5'i. 0 t -
».*tl
11.178
11.S18
12.TO3
\ S«IMW
• • £ AA 4tfA
" : W~» V*
lit 094
12.384
19.912
24.026
17.7*6
1O4941
11.S04
9.621
14.062
9.621
13.104
' 9,621
12.044'
10.793
13.135
9.621
13.796
9,621
11.107
10.612
9.621
24.658
IS. 453
15.225
20.131
10.389
9.621
14.435
16.052
9.621
12.243
11.068
16.873
11.199
24.635
24.878
12.613
13.520
20.582
9.621
10.33S
29.720
22.177
9.621
39.650
42.6 1
9.621
i2.2l5
16.04(1
0.621
1 1- . 13.
1 1 . 14r.
17.346
9.621
11.976
rOTAL COMPOUND MASS
US) WITHIN LARGE AREA
IT OEIIRED OBNI1TY
0.214
0.549
5.759
31.110
S.413
.17*
11>047
6.195
9.9S6
12.013
8.143
O.SSO
5.752
4.811
7.031
4.811
6.552
4.811
6.022
5.397
6.9r>8
4.811
' 6.878
2.886
3.332
3.184
4.811
12.329
7.976
4.567
6.039
5.194
4.811
7.217
8.026
4.811
6.121
5.534
1..687
5.600
0.739
0.746
6.306
6.760
2.058
4.811
5.167
29.720
22.177
0.062
3.065
4,262
4,81 1
6.108
li,024
4.81 1
6.11 7
',.'.75
8.673
4.811
5.988
2*1*
5.4!
S7.99
381.10
69.1!
Si. 75
110.47
61.99
99.56
120.13
18.93
S.SO
S7.S2
48.11
70.31
48.11
65.52
48.11
6O.22
S3. 97
65.68
48.11
68.78
28.86
33.32
31.84
48.11
123.29
79.76
4S.67
60.39
91.94
48411
72.17
80.26
48.11
61.21
95.34
16.87
56.00
7.39
7.46
63.06
67.60
20.58
48.11
51.67
297.20
221.77
0.62
39.65
42.6 '
4li.ll
61.08
80.24
4li. 1 1
6 •• 7
5 ,7i
. 8I-.73
4n. 11
59,88
28.9
54.5
57S.9
1270.3
691. J
•17.9
1104*7
614. S
095.6
1201.3
889.3
55.0
S75iZ
481.1
703.1
481.1
695.2
481.1
602.2
539.7
696.8
481.1
687,0
288.6
333.2
318.4
481.1
1232*9
797.6
4S6.7
603.9
519.4
481.1
721.7
802.6
481.1
612.1
553.4
168.7
560.0
73.9
74«6
630.6
676.0
205.8
481.1
516.7
297. '.0
2217.7
96.2
30f»5
426.
481.1
610.8
803.4
481.1
60|,.7
H .5
867.3
481,1
59 n, a
THICKEST
COMPOUND
(UOVSQCM)
3.00
S.67
59.86
132.03
71. 8S
84.97
114.82
64.39
103.48
124.86
92.43
5.71
59.79
50.00
73.08
50.00
68.10
50.00
62.59
56.09
68*26
50. OU
71.49
30.00
34.63
33.09
50.00
128.14
82.90
47.47
62.77
53.09
50.00
75.02
83.42
•50.00
63-63
57.1,2
17-54
58.20
7.68
7.76
65-5S
70.26
21.30
50.0,
53.71
3 18.01
230.5
10.0
41-.'
44. 30
50.0
(> 3 . 4 8
83. '.0
60,0
f 3 ,••'
',«.-,.,
00-15
50.0
62,24
-------
REFERENCES
1. Wagman, J., R. L. Bennett and K. T. Knapp. Simultaneous Multiwave
Length Spectrometer for Rapid Elemental Analysis of Particulate
Pollutants. X-Ray Fluorescence Analysis of Environmental Samples,
Ann Arbor Publishers, Inc., Ann Arbor, Michigan, 1977-
2. Berry, P. F. , T. Furuta and J. R. Rhodes, Particle Size Effects in
Radioisotope X-Ray Spectrometry, pp. 612-632 in Charles S. Barrett,
J. B. Newkirk and Gavin R. Mallett, Eds., Advances in X-Ray Analysis,
12 (1969).
3. Giauque, R. G., L. Y. Goda and R. B. Barrett, X-Ray Induced X-Ray
Fluorescence Analysis of Suspended Air Particulate Matter, LBL-2951
(June 197*0.
33
-------
APPENDIX A
SELF ABSORPTION IN A SPHERE
-------
APPENDIX A
SELF ABSORPTION IN A SPHERE
The fraction of radiation escaping from a uniform spherical source in a
specific direction can be obtained by direct integration of the attenuation
equation. Figure 5 shows a volume element, with an attenuation path 1, in
a sphere with radius R. Using Z for the macroscopic absorption cross section,
the total radiation escaping from the disc element is for unit source
strength.
Total out
from disc
r=/R2-X2
27ire~Z1 dr
r=o
2ire
r=/R2-x2
-Z/R2-r2 „
re dr
r=o
2 2
After changing the integration variable to y = /R -r and integrating by
parts, one gets
Total out m 2 £XL R e"ER
,- i. — £ lit I V c
from di sc j. 2-
-ZR
Integrating the disc contribution over the entire sphere and factoring the
final form gives
Total out _
from sphere
X=R
Total out
from disc
X=-R
35
-------
Figure 5- Geometry and notation used for describing escape of
x-ra.v from within a spherical particle
36
-------
For small values of £, this can be simplified as follows:
Total out for = k R3 (]
small £ 3
The fraction of radiation escaping compared to a non absorbing sphere is
obtained by dividing either of the last two equations by 4irR3/3.
37
-------
APPENDIX B
SERIAL NUMBER LISTS
38
-------
IIT RESEARCH INSTITUTE
Element
Compound Sought
COoO, Co
-J H-
Ti
ZnO Zn
NiO Ni
Pt02
Serial #
001-1
002-2
003-5
004-10-
005-50
006-100
007-1
008-2
009-5
010-10
011-50
012-100
013-1
014-2
015-5
016-10
017-50
018-100
019-1
020-2
021-5
022-10
023-50
024-100
031-1
032-2
033-5
034-10
035-50
036-100
Weight
(ug/cm )
0.755
1.51
3.78
7.55
37.8
75.5
0.595
1.19
2.98
5.95
29.8
59.5
1.09
2.18
5.45
10.9
54.5
109
0.718
1.44
3. .59
7.18
35.9
71.8
1.65
3.. 30
8.25
16.5
82.5
165
39
-------
IIT RESEARCH INSTITUTE
Element Weight
Compound Sought Serial # (ug/cm2)
CaF0 Ca 037-1 2.10
2 038-2 4.20
039-5 10.5
040-10 21.0
041-50 105
042-100 210
CaF9 F 037-1 1,75
L 038-2 3.50
039-5 8.75
040-10 17.5
041-50 87.5
042-100 175
MoO- Mo 055-1 1.07
— 3 056-2 2.14
057-2 5.35
058-10 10.7
059-50 53.5
060-100 107
BaSO, Ba 061-1 1.27
4 062-2 2.54
063-5 6.35
'064-10 . 12.7
065-50 63.5
066-100 127
BaSO, S 061-1 .296
* 062-2 .592
063-5 1.48
064-10 2.96
065-50 14.8
066-100 29.6
A100, Al 067-1 1.08
L J 068-2 2.16
069-5 5.40
070-10 10.8
071-50 54.0
072-100 108.
PdO Pd 073-1 2.47
074-2 4.94
075-5 12.4
076-10 24.7
077-50 124
078-100 247
-------
IITRI X-RAY FLUORESCENCE STANDARDS
Compound
iL°9
£•
Cup
MaP
wo.
— 3
SnO.
— 2
As00_
—2 3
Element
Sought Serial #
Si 043-1
044-2
045-5
046-10
047-50
048-100
Cu 049-1
050-2
051-5
052-10
053-50
054-100
Hg 079-1
080-2
081-5
082-10
083-50
084-100
w 091-1
092-2
093-5
094-10
095-50
096-100
Sn 097-1
098-2
099-5
100-10
101-50
102-100
As 103-1
104-2
105-5
106-10
107-50
108-100
WeighJ
(ug(cm )
.879
1.76
4.40
8.79
44.0
87-9
.386
.772
1.93
3.86
19-3
38.6
.847
1.69
4.23
8.47
42.3
84.7
1.34
2.69
6.72
13.4
67-2
134
.832
1.66
4.16
8.32
41.6
83-2
.765
1.53
3.82
7.65
38.2
76.5
41
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Compound
NaCl
Na
Element
Sought
Na
Cl
Ag
Serial #
085-1
086-2
087-5
088-10
089-50
090-100
085-1
086-2
087-5
088-10
089-50
090-100
109-1
110-2
111-5
112-10
113-50
114-100
Weight
(yg/cm )
1.11
2.22
5.55
11.1
55.5
111
1.71
3-43
8.56
17.1
85.6
171
5.5
11.0
27.4
54.8
274
549
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TECHNICAL REPORT DATA "1
(f leave read Instructions on the reverse before completing) I
1 REPCRT NO. !2 " ' ' "
EPA-600/2-78-197 !
4, T T^E AND SUBTITLE
CALIBRATION STANDARDS FOR X-RAY SPECTROMETERS USED
FOR POLLUTION SAMPLE ANALYSIS
7. ACTHOR(S)
F.H. Jarke, 0. Puretz, R.A. Semmler, and R.G. Draftz
9 PERFORMING ORGANIZATION NAME AND ADDRESS
I IT Research Institute
10 West 35th Street
Chicago, Illinois 60616
12. SPONSORING AGENCY NAME AND ADDRESS
Environmental Sciences Research Laboratory - RTP, NC
Office of Research and Development
U.S. Environmental Protection Agency
Research Triangle Park, N.C. 27711
3. RECIPIENT'S ACCESSION NO. 1
5. REPORT DATE
September 1978
6. PERFORMING ORGAN 1 ZATI ON CODE
8. PERFORMING ORGANIZATION REPORT NO.
10. PROGRAM ELEMENT NO.
1AD712 BD-07(FY-76)
11. CONTRACT/GRANT NO.
68-02-1734
13. TYPE OF REPORT AND PERIOD COVERED
Final 8/75 - 3/77
14. SPONSORING AGENCY CODE
EPA/600/09
15. SUPPLEMENTARY NOTES
6. ABSTRACT
A technique is described for making aerosol standards for x-ray fluorescence
analysis by depositing sized particles suspended in a carrier solution onto the
surface of a polycarbonate filter. Size is controlled by a separate sedimentation
step following grinding in a boron carbide mortar and pestle. Binding of the
deposition to the filter is accomplished by a collodion film layer applied both
before and after the particle deposition. The deposited mass is determined
gravimetrically from a companion filter prepared from a large volume aliquot of
carrier solution and without collodion. Standards for 18 different elements have
been prepared.
17. KEY WORDS AND DOCUMENT ANALYSIS ~~ |
a. DESCRIPTORS
Air pollution
Aerosols
Calibrating
*Stcmdards
Xray spectrometers
Xray fluorescence
18. DISTRIBUTION sTATEMtiN i
RELEASE TO PUBLIC
b. IDENTIFIERS/OPEN ENDED TERMS
19. SECURITY CLASS (This Report)'
UNCLASSIFIED
20. SECURITY CLASS (This page)
UNCLASSIFIED
c. COSATI Field/Group 1
13B
07D
14B
20F
21. NO. OF PAGES
51 1
22. PRICE
rm 2220-1 (Rev. 4-77) PREVIOUS EDITION is OBSOLETE
43
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