1879-
Elizabeth Rona worked with Marietta Blau at the Kaiser Wilhelm Institute in Vienna on ionization caused by proton rays. [38 LH]
With George von Hevesy, at the University of Budapest: "My first paper was analytical. Hevesy drew my attention to Antonoff's work at Rutherford's Manchester laboratory. He separated a new radioactive element from uranium salts: a beta emitter, "UY". Later Soddy and Fleck were unable to verify Antonoff's results. Hevesy asked me to repeate Antonoff's experiments, using methods of precipitation and fractionation to eliminate uranium and all its daughters interfering with the new element. I succeeded to verify Antonoff's results. Hevesy was the first to introduce radioactive elements as indicators in chemical and biological processes." "I separated UY from all of the interfering elements, a beta emitter with a half life of 25 hours. It was now to decide where to place this new element. As far as we knew, Antonoff did not know it either. Only after the uranium isotope U-235 was discovered and uranium-235 was established as the first element of a new series (the actinium series) was the element UY found to be an isotope of thorium: Th-234, daughter of U-235 and parent of Pa-231. Soon after the paper was published in the Hungarian Academy of Science, Soddy, Hahn, and Meitner also verified Antonoff's results." [Niels Bohr Library]
At the Radium Institute, Vienna: "What happens to elements that are already radioactive if they are bombarded with neutrons? Experiments on this line were taken up by Fermi's group, by Otto Hahn and Lise Meitner, and later were joined by Strassman, the Joliot-Curies, and our group in Vienna. Before these experiments, we bombarded rare earth elements. The Radium Institute had a collection of rare earths, which had little cumbersome radioactive contamination. This material was given to the Radium Institute by Ayer von Welsbach, the developer of the gas mantle." "We discovered a thullium isotope, Tm-171, of approximately three months half-life, an europium isotope of 60 minutes, and alkaline earth cesium of a two-year half-life. These were the longest half- lives known at that time. This was possible because the Radium Institute had strong neutron sources. Professor Meyer was a collector; he possessed secondary standards, kept in a safe for no practical usage. We finally persuaded him to let us use them for neutron sources. At that time they consisted of a mixture of radium and beryllium. Because the alpha particles of the range of daughters of radium, even those of Po-214, are short, an intimate mixture of radium and beryllium powder was necessary. That was a dangerous operation, not only damage from radiation, but also the possibility of inhalation of beryllium powder, which can cause lung lesions similar to silicosis or black lung. We soon joined the other laboratories in bombarding radioactive material. The Fermi group and Hahn, Meitner, and Strassman used uranium as a target; the Joliot-Curies used, besides uranium, that of thorium. We chose thorium. We had a thorium source which was purified from Th-228 and Ra-228 several times a year, for a long time, and was reasonably free from cumbersome radioactivity of daughter products. We maintained a steady correspondence with the Joliot-Curies, comparing results. We discovered a one-minute product, which was confirmed by Irene Curie, and a forty-two minute, which resembled a 3.5-hour product, discovered by Irene Curie. Both resembled a rare earth, especially lanthanum. Conditions were not ripe at that time to draw any other conclusion that they are actinium isotopes and to be arranged in series, simulating those of natural radium families. We also bombarded thorium with slow neutrons and found a twenty-three minute thorium, Th-223, which decays to Pa-233 of a very long half- life, also discovered by Hahn and Meitner." [Niels Bohr Library]
For the Radium Institute, but stationed at Borno, on Gullmarfjord, in South Sweden: Rona was asked to analyze red clay samples taken from the ocean for their radium content. "When I analyzed the samples I could show that in several samples of red clay and radiolarian ooze, the radium content was indeed high..but high radium content had not been found in all samples taken from great depths; some were even poor in radium; nor was there any apparent relationship between radium content and depth of the water, as had been inferred by Joly's results. We thought his discrepancy could only be solved if we knew exactly the concentration of the radioactive elements in sea water. Such measurements had been carried out before, but the results differed considerably. Joly found values as high as 40x10(-12) grams in 1000 milliliters of sea water, whereas other scientists found none. We started to carry out the determination of radium in sea water, taken from Gullmerfjord and from the more open sea of Scagerak. An average of 0.7x10(-15) grams per 1000 milliliters of water was found from waters taken from shallow water to waters of 670 meter depth." "The difference in the radium content of sea water and sediments found by different scientists made it imperative to know the uranium content of sea water, the parent of radium. To know the geochemistry of radium one has to know whether it is in equilibrium with its parent uranium, or whether it deviates from it. The equilibrium of radium to uranium is one gram of radium to three million grams of uranium. The method to determine radium is relatively simple. No method is known to determine the amount of uranium in sea water. Because of the long half-life of 4.5 billion years, the activity is so low that a direct measurement, in volumes possible to handle, is out of the question. Frederick Hernegger used a different approach at the Vienna Radium Institute. The method takes advantage of the brilliant fluorescence in ultraviolet light of uranium fluoride, a method so sensitive that minute quantities of uranium can be determined. The method was further developed and improved and applied to sea water by Hernegger and Berta Karlik. The method to determine radium and uranium was carefully checked with respective standards of known uranium and radium content. By dividing the sea water samples, it was feasible to determine both in the same water sample. Later work demonstrated the shortcomings of the uranium method, but for a time it was the only method available, and it already permitted one to arrive at a rough estimate of the ratio radium to uranium in sea water; it was too low." [Niels Bohr Library]
"Extensive determinations of radium in cores from the Pacific and Atlantic Oceans were carried out by Kroll, a visiting scientist on the Albatross. In one of the cores he integrated the total radium content down to the level, where practically all the thorium-230 precipitated from the supernatant water had time to disintegrate; thus, only a very small amount remains. This should permit a comparison between the radium in the core and the supply of radium derived from the uranium in the super-posed water column of sea water. Kroll found that the radium content was three times higher than the uranium-equivalent should have been, basing his calculations on the uranium content of the sea water, 36x10 [unclear] grams in 1000 milliliters accepted at that time. Koczy later forwarded the hypothesis that several thousand years ago the uranium concentration of the sea was three times that of the present. I could think of a simpler explanation...remembering the shortcomings of the fluoro- metric method used at that time. I set out to use a method that was not dependent on the determination of the absolute amount of uranium; this is possible, with the use of isotope dilution. In that method a standard, commonly called 'spike,' is added to the sample to be analyzed; the standard is enriched with an unusual isotope, uranium-235. After the 'spike' is added to the sea water sample, it will show a new isotope ratio, determined by mass spectrometry. The ratios of uranium-235 to uranium-238 in the standard and that of the recovered sample from the sea water permit one to calculate the uranium concentration three times of that determined before, and explained the discrepancy Kroll found. An important results was that that the uranium content of the world oceans is remarkably constant, and is also the same from surface of the oceans to depths." [Niels Bohr Library]
Through Brian O'Bryen, of the Institute of Optics, University of Rochester, Rochester, NY, Rona worked on a confidential project to produce enough polonium and Pb-210 for the war effort. Bryen told her that "A stockpile of radon seeds will be available. At first, it will be necessary to produce these elements in amounts corresponding to about 50 mg of radium, and it is desired to obtain this quantity in the shortest period of time. It is probable that considerably larger amounts will be needed thereafter. Solutions of Po-210 and Pb-210 should be without contamination with inactive material. It is also desirable that these solutions should be strong and either not at all or slightly acid." To help her, Bryen instructed her to hire an assistant who knew nothing about physics so would be unable to analyze the procedure. [Niels Bohr Library]
The following year, Bryen again asked her to participate in a
project, but through the Office of Scientific Research and
Development (OSRD). Despite the fact that Rona was not a US
citizen, Bryen forced the government to grant her clearance.
In the end, Rona created a metascope, a zinc sulfide screen, with
the best characteristics of a scintillation screen. OSRD asked her
to give the design to the Canadian Radium and Uranium Company. She
did so and receive no compensation when it went into mass
production for OSRD. [Niels Bohr Library]
to be submitted
to be submitted
After Ph.D. - Technical University, Karlsruhe, Germany [Niels Bohr
Library]
Worked with George von Hevesy, a lecturer at the University of
Budapest. [Niels Bohr Library]
1918-20 Instructor in Biochemistry, Budapest
1922-24 Fellow, Kaiser Wilhelm Institute
1924-38 Radium Institute, Vienna
Several Months, Curie Institute, Paris, France (on four different
occasions) [Niels Bohr Library]
1941 Geophysics Laboratory, Washington, D.C.
1941-46 Associate Professor, Trinity College
1947-51 Chemist, Argonne National Laboratory
1951-65 Oak Ridge Institute for Nuclear Studies
1965-[at least] 71 Institute for Marine Science, University of Miami
B.A. Budapest [year?]
Ph.D. (chemistry) Budapesti Muszaki Egyetem 1900 [Niels Bohr Library]
[amws1971], 38 LH, Neils Bohr Library
After earning her Ph.D. in 1900, Rona studied at the Technical University in Karlsruhe, Germany. There she worked under George Bredig, the leading physical chemist of his day. In her manuscript, How it Came About, Rona recalled Occasionally, Bredig invited his students over to his house for tea. "The only drawback was that I had to join the ladies, being a woman, the only one at the time in the laboratory. I was much out of place. The conversation was about children, cooking, preserves. Recipes were exchanged; to these I could not contribute. How I longed to be with my colleagues, to hear and talk shop." [Niels Bohr Library]
"After the untimely death of [Dr. Francis] Tangl from pernicious anemia, the political situation in Hungary suddenly and dramatically changed. Almost overnight the communists took over. Their leaders, indoctrinated in Russia, took over all the positions and had enough armed forces to back them up. The putsch occurred on my birthday, and I was supposed to join my family at a matinee at the opera to hear Strauss' 'Fledermaus.` I received a frantic telephone call to the laboratory: by no means should I go to the opera house but should go home as soon as possible. I learned that a group of communists invaded the opera house; everybody had to stand up while they sang the International. I learned later that one priest who did not was later executed. A reign of horror followed. Ten communists took over our apartment, leaving us only one room. The situation was impossible; we moved into my aunt's already overcrowded apartment. Inflation was soaring; food was, for non-members of the party, extremely scarce, only available for peasants, who did not take money but jewelry, fur coats, etc. Communists plundered the homes; whatever money we had we buried under the wood paneling of one room. The reign of terror lasted only a few months, and was followed by the equally bloody counter- revolution, the white terror. Some of my colleagues joined the communist party, for purely idealistic reasons, and the Institute was beleagured by the 'White` terrorists; but the new director stood behind the heavy door and made a heroic resistance. It became clear that nobody who had anything to do with the communists was safe. Very soon the Institute was almost depleted of its staff, and I had to fill in the vacancies, so that the teaching and laboratory exercises could go on, though at a slower pace." [Niels Bohr Library]
Rona worked with Lise Meitner and Otto Hahn at the Kaiser Wilhelm Institute after Hahn offered Rona a grant to do research there. [Niels Bohr Library]
"The conditions in Germany became so bad that only institutions whose research was important to the nation's economy could receive grants. I was transferred to the Textile Institute of the Kaiser Wilhelm Institute. I did not mind to get experience in a completely different field; it was a new challenge. Inflation was tremendous. We received our salary daily, and had to spend it immediately. We pooled our money together and bought some not perishable food, such as a bag of potatoes. We had to carry the million marks in large sacks. If one went by subway to attend a seminar in Berlin and had no return ticket, one could not buy one because the money was worthles by the evening." [Niels Bohr Library]
Curie Institute: "The Curie Institute was...highly contaminated. The staff was more concerned of the safety of the radium sources than their own. Mmle. Chamie, who became my friend, was the custodian of the radium preparations. It was her duty to get the preparations out of a safety box in the morning and return them in the evening. A small cart with some (but not enough) lead bricks was around the radium preparation; she pushed it from and to the safe. Every evening we left together because we did not live far from each other. But each evening I had to wait outside, because she went back to see whether she really returned the radium preparation. The fear to lose some of the precious material certainly contributed to the high toll which over exposure took of the scientists at the Curie Institute. Health physics was nonexistent, and the radiation dosage to which one was exposed was unknown." [Niels Bohr Library]
She fled the Nazis and immigrated to the US in 1941. [Niels Bohr Library]
"In 1941 I made a big decision. Hungary was threatened in two directions; one side, the right bank of the Danube, Russians; the left, the Germans. There was no future for me in the near future. It is a hard decision to leave your country to which you are bound with many ties. I still had some hopes for a free Hungary, and applied for and received a visitors' visa to America." [Niels Bohr Library]
"One of my first trips to New York was to Columbia University, where I knew that some of my former colleagues did some kind of research. I went straight to the Physics Department. I saw Fermi, Szilard, and quite a few whom I had met previously. I had the quaint impression that they did not know me. Nobody talked to me. A scientist, formerly from Vienna, to whom I brought special greetings from his former professor, turned his back and fast departed. Many years later Professor John Dunning, the only scientist who talked and was kind to me, explained the situation. Men from the FBI were present all the time, questioning them about what I, a person with a visitors' visa, was doing at the laboratory where such secret work is done. Surely I would go back to Germany and report some secret results." [Niels Bohr Library]
secwp@physics.ucla.edu