One reason that ordinary analytical methods are so slow, in this case, is because the amount of copper you are looking for is so small that you would have to dissolve a large amount of plastic to get enough copper to measure. You know that nearly all the plastic is carbon, hydrogen, and oxygen and that none of these elements are easily made radioactive when they are bombarded with low-energy neutrons. You look in a table to see if copper is easily activated. You find that there are two stable isotopes of copper having atomic weights of 63 and 65. Each of these is easily activated, giving radioactive isotopes, copper-64 and copper-66. The latter has a half-life of about 5 minutes and emits gamma rays with energies of 1.039 MeV, which are easy to measure.
In the research building next door, there is a small reactor that can irradiate encapsulated samples with low-energy neutrons at the rate of a million million neutrons per square centimeter per second (10¹² neutrons/cm²/sec). You calculate that if you irradiate only one tenth of a gram of the plastic for 10 minutes, and if the plastic contains only one part of copper in one million parts of plastic, then at the end of the irradiation the radioactive copper formed will be emitting over 400 gamma rays per second. There is a pneumatic tube that can remove the irradiated sample in 20 seconds, and you decide that it will take only a minute or two to remove the sample from its capsule and get it into a gamma-ray counter located nearby. The counter is a scintillation counter that is connected to a pulse-height analyzer.
If you count for only 10 minutes you will detect about 1000 gamma rays of the right energy (allowing for the inefficiencies of the detector system). This sounds like itshould do the job. But does the good plastic contain copper too? And how much does it take to produce the discoloration?
You decide to use neutron activation analysis and to analyze samples of faulty plastic, normal plastic, and a small piece of copper foil, which you have weighed and sealed in a small polyethylene bag as a standard. Your results are shown in the table below.
It worked! The faulty plastic contains 100 times as much copper as the good plastic, specifically 100 parts per million. (If 0.1 milligrams of pure copper gave 1,000,000 counts, then the 0.1 grams of faulty plastic contains (100,000/1,000,000) · 0.1 milligrams or 0.01 milligrams of copper. This is one ten thousandth of the weight of the plastic or 0.01% or 100 ppm.) You relay the information to the plant superintendent almost before he finishes his lunch. He now knows what to do and the crisis is over.
You are a curator working with the ancient coin collection of a large museum. A donor has just given themuseum a group of 50 gold coins presumably about 1500 years old. After months of careful study, you have satisfied yourself that most of those coins are genuine specimens of that period. Judging from your experience, you decide that a small group of five are definite forgeries.
However, there are three others that you suspect are also fakes, but you are not quite certain. You know that both genuine minters and forgers often tried to save money by diluting their gold with less expensive metals such as silver and copper. Since the chances are slim that the forger’s product has the same concentration of gold, silver, and copper as the genuine coins, you realize that a chemical analysis would help you decide if the doubtful pieces were real or fake.
An accurate chemical analysis would require a sample of such size that the coin would be ruined as a museum specimen. You need an analytical method that can be applied to an infinitesimal sample.
You are not a scientist but you’ve heard about neutron activation analysis. Therefore, you contact a radiochemist at a local university who is an expert in this field.
He decides to use a sampling technique developed by scientists at Brookhaven National Laboratory for sampling metal objects of archaeological interest. You obtain from him a set of 50 quartz plates that have been ground on one side. Following his instructions, you carefully scrape away a small area on the edge of each coin. You then rub each freshly cleaned area across the ground surface of one plate leaving a minute streak of metal similar to a pencil mark.
At the scientist’s laboratory, each plate is carefully placed inside a quartz tube. No attempt is made to weigh the tinystreak of metal since you wish only to compare the ratios of the metal concentrations. However, because the samples make a rather bulky package, the scientist is concerned with the uniformity of the neutron flux that each sample will “see”. He therefore also places in each tube an exactly equal weight of a gold—silver—copper alloy wire (of known proportions) to act as a standard neutron-flux monitor. The tubes are then sealed and taken to a reactor to be irradiated for 12 hours.
After the samples are removed from the reactor, the scientist carefully breaks open each of the quartz tubes and places the sample and the standard piece of wire in separate numbered plastic capsules with lids. For an accurate comparison, each capsule is prepared in the same manner. About 4 hours after the samples are removed from the reactor, he begins the radioactivity measurements.
The sample capsules are loaded into an automatic sample-changing mechanism that places each one into an identical position above a lithium-drifted germanium detector. (See the chapter beginning onpage 19.) Gamma-ray spectra are collected all day, first from a sample, then from its accompanying standard. Each count takes 2 minutes, and 3 minutes are required between counts for data printout and sample changing. A typical gamma-ray spectrum looks like the one in thefigure on the next page. Notice that only gold (gold-198) and copper (copper-64) show up in this short counting time. Later on, radioactivity from silver (silver-110m) can be measured using a longer counting time. This can be done because while the activation products from copper and gold have relatively short half-lives (12.8 hours and 2.7 days, respectively), that from silver has a half-life of 270 days. To increase the sensitivity of the analysis for silver, the scientist repackages and re-irradiates the samples and wires for 100 hours. Silver-110mis one oftworadioactive isotopes of silver that have thesamemass. In this case, one has a higher energy than the other and decays in a different way. This is known as an isomeric state and it occurs for many other elements as well as for silver.
Graph: “Counts in one minute per 3.1 KeV channel” _vs_ “Channel”
The spectrum obtained from a streak of metal on a quartz plate after a 3-hour exposure to neutrons in a reactor and a 6-hour delay before counting. The activation products of gold and copper are obviously present and are easily measured in only 1 minute.
Graph: “Counts per 100 minutes per 3.2 KeV channel” _vs_ “Channel number”
The spectrum obtained from the same streak of metal after re-exposure to neutrons for 100 hours and a delay of approximately 2 months before counting. Activation products from gold and copper have decayed away and the gamma-ray spectrum of silver-110m is now observed. In this case the sample is closer to the detector than for the earlier measurement and the measurement takes 100 minutes.
Two months later, the scientist repeats the procedure of counting the samples and standards, except that this time the plastic capsules are closer to the detector, each count is for 100 minutes, and the sample changer operates for about a week. A typical spectrum looks like that in thefigure on page 39.
The scientist can now compute ratios for the three elements in each sample and compare them with the standard, but he decides that a computer could do it faster and with fewer errors. The data collected during the two series of counts are therefore sent to a data processing center where, in a matter of minutes, a computer does the following for each of 50 samples:
1. Finds the 0.411-MeV gamma-ray peak for gold-198.2. Determines the total counts in the peak.3. Repeats the process for the corresponding wire standard.4. Corrects the total count for the wire for the small amount of radioactive decay that occurred in the few minutes between the sample count and the standard count.5. Computes the ratio: [total count for sample/total count for standard (corrected)]6. Repeats all the above for the 0.511-MeV gamma ray for copper-64 and (in the longer counts) for the 0.658-MeV gamma ray for silver-110.7. Computes the ratios: [sample to standard (for copper)/sample to standard (for gold)] and [sample to standard (for silver)/sample to standard (for gold)].8. Tabulates and prints the ratios found in Step 7.
1. Finds the 0.411-MeV gamma-ray peak for gold-198.
2. Determines the total counts in the peak.
3. Repeats the process for the corresponding wire standard.
4. Corrects the total count for the wire for the small amount of radioactive decay that occurred in the few minutes between the sample count and the standard count.
5. Computes the ratio: [total count for sample/total count for standard (corrected)]
6. Repeats all the above for the 0.511-MeV gamma ray for copper-64 and (in the longer counts) for the 0.658-MeV gamma ray for silver-110.
7. Computes the ratios: [sample to standard (for copper)/sample to standard (for gold)] and [sample to standard (for silver)/sample to standard (for gold)].
8. Tabulates and prints the ratios found in Step 7.
Graph: Number of coins at indicated ratios vs. Copper/gold ratio
Radioactivity ratios for 50 “gold” coins. Above are the silver to gold ratios. There are two groups of genuine coins. Five known forgeries show considerably higher ratios than the genuine coins. Two of the suspect coins also show high ratios but the third, suspect A, shows a ratio that falls into one of the genuine groups. Below are the copper to gold ratios. Again there are two groups of genuine coins. (The same coins make up the two groups here as above.) The five known forgeries again show higher ratios than the genuine ones and again the same two suspects appear to be forgeries. Suspect A, however, shows a ratio similar to one group of the genuine specimens. One therefore concludes that suspect A is genuine and that B and C are not.
For example, suppose forsample 1there are 20,000 counts in the 0.412-MeV peak (gold), 190 counts in the 0.511-MeV peak (copper), and 450 counts in the 0.654-MeV peak (silver). Suppose also thatstandard 1yielded 10,000, 500, and 400 counts for these three peaks (corrected for decay), respectively. Then the ratio for gold would be (20,000/10,000) = 2.00, the ratio for copper would be (190/500) = 0.380, and the ratio for silver would be (450/400) = 1.13.
Finally, the activity ratio of copper to gold would be (0.380/2.00) = 0.190, and the activity ratio of silver to gold would be (1.13/2.00) = 0.565.
Because each sample was irradiated with an identical standard, and counted in an identical arrangement, the last two ratios will be the same for different samples if, and only if, the concentrations of gold, silver, and copper in those samples are in identical proportions. This will be true no matter where in the reactor or for how long the irradiation took place.
Now the scientist presents the data to you. You immediately see that (a) the good coins fall into two groups, one with a silver to gold activity ratio of approximately 0.56 and a copper to gold ratio of approximately 0.20 and a second group with these ratios approximately 0.51 and 0.18; (b) the coins you were certain were forgeries have distinctly higher ratios ranging from 0.60 to 0.65 for silver to gold and from 0.23 to 0.30 for copper to gold; and (c) of the three suspected coins, two have ratios that fall into the range of the known forgeries, but one, with ratios of 0.552 and 0.198, is probably genuine.
You present the result to the museum director in the form of a graph (see thefigure on page 41) and a few weeks later, 43 coins are added to the permanent exhibits of the museum, while 7 are discarded.
You are a scientist working in the criminology laboratory of a large metropolitan city. A detective brings you a minutesample of paint taken from the clothing of a hit-and-run victim. He has a suspect whose automobile paint seems to match that sample. The suspect was found in his parked automobile, not far from the scene of the accident. He seems to fit the description given by two witnesses, and he is extremely nervous. You scrape a small sample of paint from a recently damaged area of the suspect’s car, and, (with the aid of a microscope) find that the pigment content seems to be the same as that taken from the victim’s clothing. But, are they really from the same paint?
You know that paint, like almost everything else, contains very small quantities of impurities that are present only by accident and do not affect its properties as a useful material. The trace impurities, as they are called, will vary from batch to batch of the same paint. Very rarely will a match be obtained in both type and concentration of trace impurities in two samples if they are not from the same batch.
By measuring a sufficient number of different elements, the probability of accidentally matching two samples can be as rare as the duplication of fingerprints in two individuals. Matching of trace impurities is often called a “fingerprint” method.
With neutron activation analysis, you can obtain the “fingerprints” of the two samples to see if they match. Although this kind of evidence may be difficult to use as proof in court, a positive match will let the detective know that he is on the right track. Also, the suspect might confess if he is confronted with the evidence and realizes that he is “caught”. On the other hand, a mismatch will clear the suspect completely and the detective will know to look elsewhere for the criminal.
You seal each sample in a tiny polyethylene bag about ½ inch square. One sample is taken from the victim’s clothing and the second, about the same size as the first, taken from the damaged area of the automobile. In preparing these samples, you handle all the materials with clean forceps because you realize that the most minute dirt from your fingers will be detected in the analysis.
The two bags are irradiated together for 1 hour in a nearby reactor and 2 hours later you begin counting the samples with a high-resolution, lithium-drifted-germanium, gamma-ray spectrometer. This will give you a match (or mismatch) for elements that yield radioisotopes of fairly short half-life such as manganese (2.56 hours), copper (12.8 hours), sodium (15 hours), arsenic (27.7 hours), etc. You plan on “counting” the samples again later on, if the first counts match, so that you can check on radioisotopes with longer half-lives such as iron (45 days), chromium (27 days), silver (270 days), cobalt (5 years), etc.
The two gamma-ray spectra you obtain look like those in thefigure on the opposite page. The gamma rays from the irradiated paint taken from the victim’s clothing indicate the presence of the common elements sodium, potassium, and copper, but gold, lanthanum, and europium are also conspicuously present. The gamma rays from the other sample also reveal sodium, potassium, and gold but in rather different proportions. More striking is the absence of copper and the two rare earths, and the presence of manganese and arsenic, which were not indicated in the first sample.
The paint samples definitely do not match. Therefore, you inform the detective that his suspect is innocent after all. You’ve solved your problem, but he still has his. Perhaps the same technique will provide positive proof when he finds the real culprit.
Graph: “Counts/10 min per 3.3 KeV channel (arbitrary scale)” _vs_ “Channel number”
Graph: “Counts/10 min per 3.3 KeV channel (arbitrary scale)” _vs_ “Channel number”
Gamma-ray spectra of two samples of paint. These two spectra are obviously different and, therefore, could not have come from the same source.
These five situations are intended to show why neutron activation analysis is used, when it can be applied, and how it works.
In the real world, there are often many reasonswhythis kind of analysis is used. As in the situations described here, it may be the only workable method. Sometimes there may be a choice of methods, but activation analysis is used because it has certain peculiar advantages or because it happens to be the most convenient. There are other times, however, when other analytical methods can and should be used. Such situations arise when the element sought is not easily activated, or when a satisfactory alternative method exists that is more economical or more convenient. The points to remember about the use of activation analysis are that:
1. In many cases, no elaborate sample preparation procedure is required.2. For many elements, it is the most sensitive analytical technique known.
1. In many cases, no elaborate sample preparation procedure is required.
2. For many elements, it is the most sensitive analytical technique known.
The diversity ofapplicationsin which activation analysis is used is enormous and will probably continue to be. The examples given here represent only a tiny fraction of circumstances in which the method has been used. Consider that it has been used successfully:
1. In the microscopic world of biology and medicine;2. For meteorites arriving from the vast reaches of space;3. In the production lines of consumer products;4. For precious samples of moon rocks;5. In the most “down-to-earth” business of hunting for new mineral sources;6. For exploring the causes of Napoleon’s death nearly 150 years earlier (seephotograph on next page). Today,there is virtually no field of science and technology that is untouched by this method.
1. In the microscopic world of biology and medicine;
2. For meteorites arriving from the vast reaches of space;
3. In the production lines of consumer products;
4. For precious samples of moon rocks;
5. In the most “down-to-earth” business of hunting for new mineral sources;
6. For exploring the causes of Napoleon’s death nearly 150 years earlier (seephotograph on next page). Today,there is virtually no field of science and technology that is untouched by this method.
The illustrations ofproceduresused in the situations described in this booklet are typical of some in use today. There are many other situations that require still other techniques. One of the most exciting, which will be used with increasing frequency in the future, involves the use of computers. It has been shown that data collected by high-resolution gamma-ray spectrometers can be “fed” directly to a computer. The computer can be programmed to identify unknown components and to determine the concentrations of elements of interest to the analyst. It is entirely possible to include corrections for radioactive decay, possible interferences from other elements present, and many other factors. It appears quite likely that the kinds of analyses described here (as well as others) may someday be accomplished automatically, with far smaller chances for error and probably more economically.
Hair sample
Samples of Napoleon’s hair. Neutron activation analysis of these hairs revealed that he had been poisoned with arsenic. (He died, however, not from arsenic poisoning, but from acute mercury intoxication.)
Other newer techniques that may find increased usage in the future are exemplified by the method for activation analysis of the whole human body. The use of neutrons produced by nuclear machines (such as cyclotrons or other particle accelerators) or produced by compact, portable isotopic sources will make neutron activation analysis even more versatile. Isotopic sources produce neutrons as the result of a nuclear reaction. One such reaction uses alpha particles emitted by polonium-210 (or some other alpha emitter) to bombard the element beryllium. A different kind of isotopic source is the man-made radioisotope californium-252 that decays by fissioning (splitting) spontaneously and produces neutrons in the process. (One milligram of californium-252 will spontaneously produce over 10⁹ neutrons per second.) While californium-252 is quite expensive at present, it is likely that production costs will be significantly reduced in the future.
With computers, more convenient radiation sources, and continuing improvements in the technology of gamma-ray detectors and nuclear electronics, neutron activation analysis will become more and more a routine tool of the analyst.
Calculation of arsenic concentration with no standard for comparison.
1. Determination of arsenic-76 activity produced from1microgram of arsenic at the time it comes out of the reactor.
We use the equation frompage 12:
A₀ = Nφσ (1 - e-λt)
where N is the number of target atoms. (One microgram of arsenic contains (10-6gram/75 grams per mole[12]) × 6.02 × 10²³ atoms per mole which is 8 × 10¹⁵ atoms of arsenic.)
φ is the neutron flux. (This would be known to the reactor operator. It is usually measured by inserting materials of known composition and measuring their activation. In this case, φ = 10¹³ neutrons per square centimeter per second.)
σ is the activation cross section. (Neutron cross sections have been measured and tabulated by scientists. For the activation of arsenic-75 to arsenic-76, the cross section is known to be 4.2 × 10-24square centimeter.)
λ is the disintegration constant for arsenic-76. (Here, λ = (ln 2[13]/t½,(in hours); t½, the half-life for arsenic-76, is 26.6 hours so λ = (0.693/26.6) = 0.026.)
t is the time of the irradiation. (Here t is 12 hours.)
Therefore: A₀, the activity of arsenic-76,
= 8 × 10¹⁵ × 10¹³ × 4.2 × 10-24× (1 - e-0.026 × 12)(Note: e is a physical constant, 2.71+)= 9 × 10⁴ disintegrations per second per microgram
= 8 × 10¹⁵ × 10¹³ × 4.2 × 10-24× (1 - e-0.026 × 12)
(Note: e is a physical constant, 2.71+)
= 9 × 10⁴ disintegrations per second per microgram
2. Determination of activity of arsenic measured in the sample and corrected back to the time of removal from the reactor.
We use the equation:
A₁ =RE × Feλt
where R is the measured count rate. (In this case, R is the number of counts per second observed in the 0.559-MeV gamma-ray peak, which is 5300 counts in 20 minutes or 4.4 counts per second.)
E is the efficiency of the detector. (In this case, it is the number of counts observed in the 0.559 peak for each 0.559-MeV gamma ray emitted by a radioactive material at the sample distance. This is known for the detector being used by making other measurements and, for the set-up used here, is 0.010.)
F is the average number of 0.559-MeV gamma rays emitted in each disintegration of arsenic-76. (This can be deduced from the decay scheme of arsenic-76. See thedecay scheme for manganese-56 on page 13. In the decay of arsenic-76 the number of 0.559-MeV gamma rays emitted per disintegration is approximately 0.41.)
λ is the disintegration constant for arsenic-76. (0.026, seepage 49.)
t is the decay time. (This is the number of hours from the time the sample was removed from the reactor to the time it was counted, or 5 hours.)
Therefore, A₁, the activity of arsenic-76 produced in the sample at the time of removal from the reactor,
=4.4 counts per second0.010 × 0.41e0.026 × 5 hours
= 1200 disintegrations per second
3. Calculation of arsenic concentration in the sample.
We use the equation:
Concentration in parts per million =A₁A₀ × W10⁶
where A₁ and A₀ were determined above and W is the weight of sample analyzed or 300 micrograms (0.0003 gram).
Therefore the concentration is
12009 × 10⁴ × 300× 10⁶ = 44 parts per million.
[1]There are exceptions. For a few elements there are no stable nuclei. In some cases, there are other differences that make certain atoms radioactive.[2]These gamma rays (called prompt gamma rays because they are instantaneously produced when the neutron is captured) can also be used for analysis and sometimes are, but we will not be discussing this type of analysis in this booklet.[3]Sensitivity in this case means how small an amount of an unknown element can be detected.[4]Nuclide is a general term applicable to all atomic forms of elements. Whereas isotopes are the various forms of a single element (hence are a family of nuclides) and all have the same atomic number and number of protons, nuclides comprise all the isotopic forms of all the elements.[5]The half-life of a radioactive nuclide is the time it takes for half the nuclei in a large sample to undergo decay. Note that after half of them are gone, a second half-life period will reduce theremainderby one half, leaving one quarter of the original number.[6]The disintegration constant is related to the half-life, T½, by the expression: λ = natural logarithm of 2/half-life, orλ =ln 2T½=0.693T½[7]The detector efficiency is the ratio of the number of gamma rays detected to the number emitted by the sample.[8]A deuteron is the nucleus of a heavy hydrogen (deuterium) atom and consists of one neutron and one proton.[9]Not all nuclear reactors are appropriate for this work. For example, reactors designed for electric power production do not have the means built into them for inserting and removing small samples for a “short” period of irradiation.[10]A scintillation detector is a crystalline device, usually sodium iodide containing a small amount of thallium, which has the property of emitting light when energy is absorbed from nuclear radiation.[11]After a 10-minute irradiation and a 3-minute delay before counting, corrected for decay to a common time.[12]One mole is the atomic weight of an atom or molecule expressed in grams, or the weight of 6.02 × 10²³ atoms or molecules per mole.[13]ln 2 is the natural logarithm of 2.
[1]There are exceptions. For a few elements there are no stable nuclei. In some cases, there are other differences that make certain atoms radioactive.
[2]These gamma rays (called prompt gamma rays because they are instantaneously produced when the neutron is captured) can also be used for analysis and sometimes are, but we will not be discussing this type of analysis in this booklet.
[3]Sensitivity in this case means how small an amount of an unknown element can be detected.
[4]Nuclide is a general term applicable to all atomic forms of elements. Whereas isotopes are the various forms of a single element (hence are a family of nuclides) and all have the same atomic number and number of protons, nuclides comprise all the isotopic forms of all the elements.
[5]The half-life of a radioactive nuclide is the time it takes for half the nuclei in a large sample to undergo decay. Note that after half of them are gone, a second half-life period will reduce theremainderby one half, leaving one quarter of the original number.
[6]The disintegration constant is related to the half-life, T½, by the expression: λ = natural logarithm of 2/half-life, or
λ =ln 2T½=0.693T½
[7]The detector efficiency is the ratio of the number of gamma rays detected to the number emitted by the sample.
[8]A deuteron is the nucleus of a heavy hydrogen (deuterium) atom and consists of one neutron and one proton.
[9]Not all nuclear reactors are appropriate for this work. For example, reactors designed for electric power production do not have the means built into them for inserting and removing small samples for a “short” period of irradiation.
[10]A scintillation detector is a crystalline device, usually sodium iodide containing a small amount of thallium, which has the property of emitting light when energy is absorbed from nuclear radiation.
[11]After a 10-minute irradiation and a 3-minute delay before counting, corrected for decay to a common time.
[12]One mole is the atomic weight of an atom or molecule expressed in grams, or the weight of 6.02 × 10²³ atoms or molecules per mole.
[13]ln 2 is the natural logarithm of 2.
Secrets of the Nucleus, Joseph S. Levinger, McGraw-Hill Book Company, New York, 1967, 127 pp., $0.50.Working With Atoms, Otto R. Frisch, Basic Books, Inc., Publishers, New York, 1965, 96 pp., $3.50.The Atom and Its Nucleus, George Gamow, Prentice-Hall, Inc., Englewood Cliffs, New Jersey, 1961, 153 pp., $1.95.Inside the Nucleus, Irving Adler, The John Day Company, Inc., New York, 1963, 192 pp., $4.95.Radioisotopes and Radiation, John H. Lawrence, Bernard Manowitz, and Benjamin S. Loeb, Dover Publications, Inc., New York, 1964, 131 pp., $2.50.Sourcebook on Atomic Energy(third edition), Samuel Glasstone, Van Nostrand Reinhold Company, New York, 1967, 883 pp., $15.00.The Semiconductor Revolution in Nuclear Radiation Counting, J. M. Hollander and I. Perlman,Science, 154: 84 (October 7, 1966).
Secrets of the Nucleus, Joseph S. Levinger, McGraw-Hill Book Company, New York, 1967, 127 pp., $0.50.
Working With Atoms, Otto R. Frisch, Basic Books, Inc., Publishers, New York, 1965, 96 pp., $3.50.
The Atom and Its Nucleus, George Gamow, Prentice-Hall, Inc., Englewood Cliffs, New Jersey, 1961, 153 pp., $1.95.
Inside the Nucleus, Irving Adler, The John Day Company, Inc., New York, 1963, 192 pp., $4.95.
Radioisotopes and Radiation, John H. Lawrence, Bernard Manowitz, and Benjamin S. Loeb, Dover Publications, Inc., New York, 1964, 131 pp., $2.50.
Sourcebook on Atomic Energy(third edition), Samuel Glasstone, Van Nostrand Reinhold Company, New York, 1967, 883 pp., $15.00.
The Semiconductor Revolution in Nuclear Radiation Counting, J. M. Hollander and I. Perlman,Science, 154: 84 (October 7, 1966).
Neutron Activation Analysis, Vincent P. Guinn,International Science and Technology, Prototype Issue,74 (1961).Distribution of Arsenic in Napoleon’s Hair, Hamilton Smith, Sten Forshufvud, and Anders Wassen,Nature, 194: 725 (May 26, 1962).Nuclear Activation Analysis, Richard E. Wainerdi and Norman P. DuBeau,Science, 139: 1027 (March 15, 1963).Neutron Activation Analysis, W. H. Wahl and H. H. Kramer,Scientific American, 68: 210 (April 1967).
Neutron Activation Analysis, Vincent P. Guinn,International Science and Technology, Prototype Issue,74 (1961).
Distribution of Arsenic in Napoleon’s Hair, Hamilton Smith, Sten Forshufvud, and Anders Wassen,Nature, 194: 725 (May 26, 1962).
Nuclear Activation Analysis, Richard E. Wainerdi and Norman P. DuBeau,Science, 139: 1027 (March 15, 1963).
Neutron Activation Analysis, W. H. Wahl and H. H. Kramer,Scientific American, 68: 210 (April 1967).
Activation Analysis Handbook, Robert C. Koch, Academic Press, Inc., New York, 1960, 219 pp., $8.00.Neutron Activation Experiments in Radiochemistry, K. S. Vorres,Journal of Chemical Education, 37: 391 (August 1960).Radioactivation Analysis, H. J. M. Bowen and E. Gibbons, Oxford University Press, London, England, 1963, 295 pp., $8.00.Neutron Irradiation and Activation Analysis, Denis Taylor, Van Nostrand Reinhold Company, New York, 1964, 185 pp., $8.95.Guide to Activation Analysis, William A. Lyon (Ed.), Van Nostrand Reinhold Company, New York, 1964, 186 pp., $5.95.Advances in Activation Analysis, Volume 1, J. M. A. Lenihan and S. J. Thomson (Eds.), Academic Press, Inc., New York, 1969, 233 pp., $9.50.Activation Analysis; Principles and Applications, J. M. A. Lenihan and S. J. Thomson (Eds.), Academic Press, Inc., New York, 1965, 211 pp., $8.50.Modern Trends in Activation Analysis, Volumes 1 and 2, J. R. DeVoe and P. D. LaFleur (Eds.), National Bureau of Standards Special Publication Number 312, U. S. Government Printing Office, Washington, D. C., 1969, 2005 pp., $8.50.Pottery Analysis by Neutron Activation, I. Perlman and F. Assaro,Archaeometry, 11: 21 (1969).
Activation Analysis Handbook, Robert C. Koch, Academic Press, Inc., New York, 1960, 219 pp., $8.00.
Neutron Activation Experiments in Radiochemistry, K. S. Vorres,Journal of Chemical Education, 37: 391 (August 1960).
Radioactivation Analysis, H. J. M. Bowen and E. Gibbons, Oxford University Press, London, England, 1963, 295 pp., $8.00.
Neutron Irradiation and Activation Analysis, Denis Taylor, Van Nostrand Reinhold Company, New York, 1964, 185 pp., $8.95.
Guide to Activation Analysis, William A. Lyon (Ed.), Van Nostrand Reinhold Company, New York, 1964, 186 pp., $5.95.
Advances in Activation Analysis, Volume 1, J. M. A. Lenihan and S. J. Thomson (Eds.), Academic Press, Inc., New York, 1969, 233 pp., $9.50.
Activation Analysis; Principles and Applications, J. M. A. Lenihan and S. J. Thomson (Eds.), Academic Press, Inc., New York, 1965, 211 pp., $8.50.
Modern Trends in Activation Analysis, Volumes 1 and 2, J. R. DeVoe and P. D. LaFleur (Eds.), National Bureau of Standards Special Publication Number 312, U. S. Government Printing Office, Washington, D. C., 1969, 2005 pp., $8.50.
Pottery Analysis by Neutron Activation, I. Perlman and F. Assaro,Archaeometry, 11: 21 (1969).
Activation Analysis: A Bibliography, G. J. Lutz, R. J. Boreni, R. S. Maddock, and W. W. Meinke (Eds.), National Bureau of Standards Technical Note 467, U. S. Government Printing Office, Washington, D. C., 1969, $8.50.Forensic Science: A Bibliography of Activation Analysis Papers, G. J. Lutz (Ed.), National Bureau of Standards Technical Note 519, U. S. Government Printing Office, Washington, D. C., 1970, $0.50.Determination of Light Elements in Metals: A Bibliography of Activation Analysis Papers, G. J. Lutz (Ed.), National Bureau of Standards Technical Note 524, U. S. Government Printing Office, Washington, D. C., 1970, $0.75.Pollution Analysis: A Bibliography of the Literature of Activation Analysis Papers, G. J. Lutz (Ed.), U. S. Government Printing Office, 1971, $0.45.14-MeV Neutron Generators in Activation Analysis: A Bibliography, G. J. Lutz (Ed.), U. S. Government Printing Office, 1971, $1.00.Oceanography: A Bibliography of Selected Activation Analysis Literature, G. J. Lutz (Ed.), U. S. Government Printing Office, Washington, D. C., 1971, $0.50.
Activation Analysis: A Bibliography, G. J. Lutz, R. J. Boreni, R. S. Maddock, and W. W. Meinke (Eds.), National Bureau of Standards Technical Note 467, U. S. Government Printing Office, Washington, D. C., 1969, $8.50.
Forensic Science: A Bibliography of Activation Analysis Papers, G. J. Lutz (Ed.), National Bureau of Standards Technical Note 519, U. S. Government Printing Office, Washington, D. C., 1970, $0.50.
Determination of Light Elements in Metals: A Bibliography of Activation Analysis Papers, G. J. Lutz (Ed.), National Bureau of Standards Technical Note 524, U. S. Government Printing Office, Washington, D. C., 1970, $0.75.
Pollution Analysis: A Bibliography of the Literature of Activation Analysis Papers, G. J. Lutz (Ed.), U. S. Government Printing Office, 1971, $0.45.
14-MeV Neutron Generators in Activation Analysis: A Bibliography, G. J. Lutz (Ed.), U. S. Government Printing Office, 1971, $1.00.
Oceanography: A Bibliography of Selected Activation Analysis Literature, G. J. Lutz (Ed.), U. S. Government Printing Office, Washington, D. C., 1971, $0.50.
Available for loan without charge from the USERDA-TIC Film Library, P. O. Box 62, Oak Ridge, TN 37830.
The Nuclear Witness: Activation Analysis in Crime Investigation, 28 minutes, color, 1966. This film illustrates the application of activation analysis to the investigation of criminal cases involving murder, burglary, and narcotics peddling.Nuclear Fingerprinting of Ancient Pottery, 20 minutes, color, 1970. Animated sequences are used to explain several of the analytical techniques. Part of the film shows how the research is actually done in the laboratory.The Atomic Fingerprint, 12½ minutes, color, 1964. The principles of neutron activation analysis are explained and the machines used in this work are shown. Some of its applications in crime detection, geology and soil science, analysis of art and archaeological objects, oil refining, agriculture, electronics, biology and medicine, and the space sciences are illustrated.Neutron Activation Analysis, 40 minutes, color, 1964. This film describes the nature, potentialities, and applications of neutron activation analysis. The kinds of neutron sources used and the counting techniques are shown. Examples of applications in crime detection, geology and geochemistry, agriculture, medicine, the petroleum and chemical industries, and the semiconductor industry are shown.
The Nuclear Witness: Activation Analysis in Crime Investigation, 28 minutes, color, 1966. This film illustrates the application of activation analysis to the investigation of criminal cases involving murder, burglary, and narcotics peddling.
Nuclear Fingerprinting of Ancient Pottery, 20 minutes, color, 1970. Animated sequences are used to explain several of the analytical techniques. Part of the film shows how the research is actually done in the laboratory.
The Atomic Fingerprint, 12½ minutes, color, 1964. The principles of neutron activation analysis are explained and the machines used in this work are shown. Some of its applications in crime detection, geology and soil science, analysis of art and archaeological objects, oil refining, agriculture, electronics, biology and medicine, and the space sciences are illustrated.
Neutron Activation Analysis, 40 minutes, color, 1964. This film describes the nature, potentialities, and applications of neutron activation analysis. The kinds of neutron sources used and the counting techniques are shown. Examples of applications in crime detection, geology and geochemistry, agriculture, medicine, the petroleum and chemical industries, and the semiconductor industry are shown.
Bernard Keisch
Dr. Bernard Keisch received his B.S. degree from Rensselaer Polytechnic Institute and his Ph.D. from Washington University. He is now a Senior Fellow at the Carnegie-Mellon Institute of Research at Carnegie-Mellon University in Pittsburgh. He is presently engaged in a project that deals with the applications of nuclear technology to art identification. This is sponsored by the National Gallery of Art and in the past has also received support from the U. S. Atomic Energy Commission and the National Science Foundation. Previously he was a nuclear research chemist with the Phillips Petroleum Company and senior scientist at the Nuclear Science and Engineering Corporation. He has contributed articles on art authentication to a number of journals. For ERDA, in addition to this booklet, he has writtenThe Mysterious Box: Nuclear Science and Art,Lost Worlds: Nuclear Science and Archaeology, andSecrets of the Past: Nuclear Energy Applications in Art and Archaeology.
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