Click for next page ( 364


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 363
HAROLD CLAYI ON UREY April 29, 1893-January 5, 1981 BY JAMES R. ARNOLD, JACOB BIGELEISEN, AND CLYDE A. HUTCHISON JR. HAROLD UREY WAS A SCIENTIST whose interests, accomplish- ments, and influence spanned the disciplines of chem- istry, astronomy, astrophysics, geology, geophysics, and biol- ogy. Although he was meticulous in his attention to cletail, his sights were always on broad questions at the forefront of knowlecige. His unusual powers of concentration and capacity for hard work accounted for much of his success in exploring en cl opening up major new fields of research, including his discovery of deuterium and work on isotope chemistry, isotope separation, isotope geology, en cl cosmo- chemistry. Urey's approach to a new area began with his becoming thoroughly familiar with what was known about the subject of his curiosity en c] then the formulation of a theory to explain a large amount of uncorrelated material, which was then followed by carefully planner! experiments. The latter frequently involves! the design of new experi- mental equipment beyond] the state of the art. As a graduate student in physical chemistry in the early A part of the section "Urey's Personal Life and His Political and Educational Activi- ties" in this memoir is taken with permission of the publisher from Memoir 43, by C. A. Hutchison fir., in Remembering the University of Chicago, Teachers, Scientists and Schol- ars, ed. E. Shils, copyright C)1991 by the University of Chicago. All rights reserved. 363

OCR for page 363
364 BIOGRAPHICAL MEMOIRS 1920s, Urey realized that future progress in that discipline would require a knowlecige of the quantum theory of atomic anct molecular systems, which was undergoing a revolution in Europe. He supplemented his command of mathematics en cl physics by formal coursework prior to going to the Bohr Institute in Copenhagen in 1923. His exposure there lecI to his formulation of the concept of the electron spin concurrent with but less complete than the Goucismit- Uhienbeck discovery. After completion of his text with Arthur Ruark, Atoms, Quanta and Molecules, one of the first English texts on quantum mechanics and its applications to atomic and molecular systems, Urey became interested in nuclear systematics. This led to his discovery of cleuterium. The conception of this search, the design of the experiment, the actual discovery, and its publication are a mocle! for the planning and execution of scientific research. His discov- ery of the differences in the chemical en c! physical proper- ties of cleuterium compounds lecI to his broacler interest in isotope chemistry and isotope separation. Here again he developer! the theory that lee! to the precliction of the mag- nitucle of isotope effects in the light elements. He followed this up with experiments to confirm the theory, en c! this lee! to his pilot plants that achieved the first concentration of AN, i3C, and 34S Urey's interest in (lemocratic government en c! world af- -fairs lee! to the sense of urgency that developed in the Man- hattan Project late in 1941. His major contributions and cleclication to the success of the program through his work on uranium isotope separation, heavy water production, anc! ~B enrichment and his service on the various NRDC and OSRD committees relater! to the development of the atomic bomb have never been fully appreciatecl. With the war behind him Urey conceived the isotope thermometer anct its application to geochemistry. From there

OCR for page 363
HAROLD CLAYTON UREY 365 he became interested! in the moon, formation of the plan- ets, meteorites, the abundances of the elements, en c} fi- nally, the origin of life. He was a major supporter of the manned mission to the moon and was an active investigator in the program. Harold Urey was a warm en cl generous person. He was warm in all his personal relations and generous with his time, attention, en c] resources. To have known him and worked with him were unequaled experiences for each of the authors of this memoir. None of us conic! have pre- pared this memoir alone. UREY'S EARLY LIFE UP TO HIS ENTRANCE TO GRADUATE SCHOOL IN BERKELEY Harold Clayton Urey was born in Walkerton, a small town in Indiana, on April 29, IS93. His father, a school teacher and a minister in the Church of the Brethren, diecl at the time Haroicl was just starting his elementary schooling. Upon graduation from grade school at age fourteen, Urey barely managed to pass the entrance exams for high school. But in high school he became interested in all aspects of his work, clue, he saicI, to the excellent teachers he had there, en c] he immediately became the leacler of his class in all subjects, a position he maintained throughout his high school years en cl in college. When in All at age eighteen he gra(luated from high school, Urey became a teacher in a small country school in Indiana with some twenty-five children in various grades. After one year he went to Montana, where his mother, step- father, brother, and sisters had aIreacly gone, en c! taught in small elementary schools. It was while teaching in a mining camp that the son of the family with which he was living decided to attend col- lege, and this influenced Harold to do the same. He en- ~ - 1

OCR for page 363
366 BIOGRAPHICAL MEMOIRS terec! the University of Montana in Missoula in the autumn of 1914. By carrying a heavy scheclule of courses he was able to complete his college education in three years with a straight A record, except in athletics. He click this in spite of being required by his financial situation to wait on tables in the girls' dormitory and work one summer on the railroad being built there. Many years later in his Willard Gibbs Medal adclress he spoke warmly of the inspiration he re- ceivect from the professors at the University of Montana en c! of the beginning of his interest in science due to their counseling advice, in particular the influence of A. W. Bray, professor of biology. Under Bray's guidance Haroicl ma- jored in biology, and his first research effort was a study of the protozoa in a backwater of the Missoula River. His in- terest in the origins of life, a fielc! in which he was to make a major contribution much later at the University of Chi- cago, originated with that earliest research. Bray also en- couraged him to stucly chemistry, en c! he obtained a second major in that subject. WorIcT War T began as Urey entered the university, and at the time he completed his work there in 19:~7 the Uniter! States decIarect war. He was urged by his professors to work in a chemical plant, chemists being badly neecled at that time. During the rest of the war he worked at the Barrett Chemical Company in Philadelphia. In 1~919 after the end of the war he returned to the University of Montana as instructor in chemistry. After two years of teaching he realized that if he was to advance academically he wouIc] neec! to obtain a Ph.D. cle- gree. The head of the Chemistry Department at Montana sent a letter of recommendation to Professor Gilbert N. Lewis of the Chemistry Department of the University of California, Berkeley. A fellowship was offered to Harold,

OCR for page 363
HAROLD CLAYTON UREY 367 and so in 1921, at the age of twenty-eight, he entered the University of California as a graduate student. FROM CHEMICAL PHYSICS TO ISOTOPE GEOLOGY The educational facilities, opportunities, and philosophy of Berkeley's Chemistry Department matched Urey's inter- ests. The department stressed exploration of new ideas through original research and its weekly seminars. There were a minimum of formal requirements. Urey, neverthe- less, took the opportunity to enroll in courses in mathemat- ics and physics, which he deemed essential for his educa- tion as a chemist. In an unpublished autobiography (ca. 1969), Urey described his two years as a graduate student as "among the most inspiring of any of my entire life." His thesis was self-generated. The first part was an outgrowth of his unsuccessful attempt to measure the thermal ionization of cesium vapor. Bohr, Herzfeld, and Fowler had shown earlier that the ideal gas approximation leads to a dissocia- tion instability for an atom with an infinite number of states below the dissociation or ionization limit. its partition func- tion is infinite at all temperatures. Urey and later Fermi showed that the correction of the ideal gas approximation for the excluded volume of the dissociating species leads to a convergence of the partition function of the atom or mol- ecule. Urey's result was published in the Astrophysical four- nal. When he became interested in the moon and planets, Urey was wont to tell his younger astronomy colleagues that he published a paper in the Astrophysical journal before they ~ . . am. 1 ~ ~ , entered the field. l he second part of his thesis was of lesser long-term significance. He attempted to calculate the heat capacities and entropies of polyatomic gases before the cor- rect description of the rotational energy states of molecules had been established by quantum mechanics. When Urey received his doctorate in 1923, he realized

OCR for page 363
368 BIOGRAPHICAL MEMOIRS that there was much he needec! to learn about the struc- ture of atoms and molecules. He received a fellowship from the American Scandinavian Foundation and went to the Institute of Theoretical Physics, Bohr Institute, in Copenhagen. The institute under Bohr's leadership was a major center in theoretical physics, particularly the (level- opment of the new quantum mechanics and its application to atomic ant! molecular structure. There Urey became ac- quaintecI with Heisenberg, Kramers, PauTi, and Slater and the biochemist Hevesy. Before Urey returnee! to the Uniter! States in 1924, he atten(lecl a meeting of the German Physi- cal Society where he met Einstein and James Franck, who later became lifelong friends. On his return to the United States Urey took a position as associate in chemistry at Johns Hopkins University. There he continued his association with physicists, including Ames, Herzfelc3, and Wood of Hopkins; Brickwecicle, Foote, and Meggers of the Bureau of Stanciar(ls; and Tuve of the Carnegie Institution. His research at Hopkins ranged from sr~,l~- tions on the spin of the electron to cooperative exceri- _~ rip 1 ~ r-- ments with F. O. Rice on the disproof of the radiation hy- pothesis of unimolecular reactions. With Arthur Ruark, Urey wrote Atoms, Quanta and Molecules. He had established him- self as one of the new generation of chemists who applied the new quantum mechanics of Heisenberg en c! Schroclinger to chemistry. In the fall of 1929 Urey joinecl the Columbia faculty as associate professor of chemistry. He initiated both experi- mental ant! theoretical research. In the former area his work was mainly in spectroscopy- ultraviolet spectra of tri- atomic molecules and vibrational spectroscopy. He and his student Charles Bradley measured the Raman spectrum of silico-chIoroform, a tetrahedral molecule. They fount! that none of the molecular force fields in use at the time couict

OCR for page 363
HAROLD CLAYTON UREY 369 reproduce the spectra of tetrahedral molecules. They intro- duced a new force field, the Urey-Bradley field, which is an admixture of valence bond and central force fields. The Urey-Bradley field remains in use in the analysis of the vi- brational spectra of tetrahedral molecules. Urey's theoreti- cal work at that time was directed to nuclear stability and the classification of atomic nuclei. In 1931 Urey had on the wall of his office a chart of atomic nuclei. On the ordinate his chart was labeled "pro- tons"; on the abscissa he plotted "nuclear electrons." This was prior to the discovery of the neutron. The number of nuclear electrons is the number of neutrons in the nucleus. The atomic number or nuclear charge is the number of protons minus the number of nuclear electrons. For the light elements Urey's chart showed the stable nuclei OH, 2He, 6Li, 73Li, 9Be, JOB, and JOB. From nuclear systematics, Urey and others postulated the existence of 2H, 3H, and 2He. No isotopes of hydrogen or helium other than OH and 2He were known in 1931. From atomic weight consider- ations, to be discussed below, it was estimated that, if a stable isotope of hydrogen of mass 2 existed, its natural abundance would be less than 1:30,000 parts of OH. DISCOVERY OF DEUTERIUM As early as 1919 Otto Stern reported an unsuccessful search for isotopes of hydrogen and oxygen, other than the ones of masses ~ and 16, respectively. In 1929 two Berkeley chem- ists, W. F. Giauque (who had been a graduate student con- temporary of Urey) and H. L. Johnston, discovered the stable isotopes of oxygen, TO and i8O. Their natural abundances are 0.04 and 0.2 percent, respectively. The chemical atomic weight scale was based on the assumption that oxygen had only one isotope, mass 16. The atomic weight of hydrogen was based on the relative densities of hydrogen and oxygen .

OCR for page 363
370 BIOGRAPHICAL MEMOIRS gases and the atomic weight of natural oxygen equal to 16. Aston hacI cleterminec! the atomic weight of hydrogen based on ~6 0 = 16. The chemical value of the atomic weight of hydrogen was 1.00777 + 0.00002. Aston's mass spectrograph value, 1.00778 + 0.00015, recluced to the chemical scale using the 1931 values for the abundances of ]70 and ~80 was 1.00756. To reconcile the physical and chemical atomic weights of hydrogen, Birge and Menze} postulated the ex- istence of a stable isotope of hydrogen of mass 2 with a natural abundance of ~ :4500. Urey react Birge and Menzel's communication in Physical Review in August 1931. Within days he deciclec! to look for an isotope of hydrogen of mass 2 and outlined his plan of attack. He would need a method of detection, and it wouIc! be desirable to prepare samples enriched in this isotope. The design of the experiment was a moclel of how one shouIc! conduct a search for a small effect. It was the proto- type of the characteristics of Urey's work for the next two decades. As a method of ctetection, Urey en c! his assistant George Murphy chose the atomic spectrum of hyclrogen. An isotope of hydrogen of mass 2 should have reel shifted lines in the Baimer series. The shifts couIcl be calculated from the Ryclberg formula for the energy levels in the hy- cirogen atom after taking into account the relative masses of the electron and nucleus. They amountec! to I.] to I.S A in four lines in the visible part of the spectrum. These couIcl readily be resolvecl with the 21-foot grating spectrograph that hac! just been installer! at the Pupin Laboratory of Co- lumbia University. The latter had a (dispersion of I.2 A/ millimeter in the second order. To enrich the heavy iso- tope, Urey and Murphy chose the clistillation of liquid hy- cirogen. They estimated the fractionation factor for THIGH from THE in the range between the freezing and boiling points from a Debye mocle! for liquid hydrogen. Their esti-

OCR for page 363
HAROLD CLAYTON UREY 371 mated fractionation factor was 2.5. To achieve an overall enrichment of 100 to 200 above natural abundance would require evaporating 5 liters of liquid hydrogen to ~ ml. The heaw hydrogen should be in this I-ml residue. There were , , ~ . . . ~ . ~ ~ ~ ~ 1 ~ . . ~ 1 ~ ~ I ~ ~ ~ but two places in the United States capable ot procruc~ng ~ liters of liquid hydrogen in 1931. They were Giauque's labo- ratory at the University of California and the low-tempera- ture laboratory at the National Bureau of Standards in Wash- ington, D.C. The NBS cryogenic laboratory had been established by Hopkins physics graduate F. G. Brickwedde, , c' ~ . , _ who overlapped with Urey at Hopkins. It is not difficult to understand why Urey chose to collaborate with Brickwedde. During the period when Brickwedde was preparing the enriched sample, Urey and Murphy determined the opti- mum conditions for excitation of the atomic spectrum of hydrogen and suppression of the molecular spectrum. They did in fact find the lines to be expected for 2H in the atomic spectrum of natural hydrogen. They delayed publi- cation until these lines could be shown to increase in inten- sity in an enriched sample. In particular, it was necessary to rule out any possibility that the 2H lines were artifacts (e.g., ~~ ~ ~~ A. ~ ~. ~1 _ 1 _~ I '~ghost77 lines trom periodic errors In tne ruling or one grar- ing or lines from the molecular spectrum). The first of _ r~c~wectcte s samples showed no increase in the intensities of the lines attributed to 2H. A less persistent person than Urey would have dropped the search. Brickwedde then pre- pared two more samples each by evaporation of a 4-liter batch of liquid hydrogen, this time close to the triple point, where the enrichment factor is somewhat larger than at the normal boiling point. Spectroscopic examination of these samples on Thanksgiving Day of 1931 confirmed the dis- covery of hydrogen isotope of mass 2, subsequently named deuterium. Urey reported his success to his wife, Frieda,

OCR for page 363
372 BIOGRAPHICAL MEMOIRS when he returned to his home in Leonia, New Jersey, hours late for Thanksgiving dinner. For the discovery of cleuterium, Harold Urey receiver! the Nobel Prize in chemistry in 1934. Urey was the thirc! American to receive a Nobel Prize in chemistry. He was young in comparison with most Nobel laureates in chemis- try prior to or since 1934. He was the first of the California school to receive a Nobel Prize. He valued the contribu- tions that his associates macle to the discovery for which he received the recognition ant! sharer! one-quarter of the prize money with F. G. Brickweclcle and G. M. Murphy. In Urey's Nobel lecture, cleliverec! on February 14, 1935, he called attention to the fact that Aston had just recleter- mined the physical atomic weight of hydrogen to be 1.0081. This value, if correct, wouIcl have brought the physical and chemical atomic weights of hydrogen into exact agreement and invaliciatec! the basis of Birge ant! Menzel's prediction. Urey would not have undertaken the search for cleuterium in 1931 and its discovery wouIc3 have been clelayect, perhaps for years. In 1932 Washburn anct Urey discoverer! the elec- trolytic separation of (leuterium from hydrogen. Dihy(lrogen gas generated by the electrolysis of water is depleted in cleuterium. This fractionation explains the failure of Urey and Murphy to finch any significant enrichment in cleute- rium in Brickwedde's first sample. Brickwecicle took special precautions before he undertook preparation of the en- richecT samples. He took all of his equipment apart and cleaned it thoroughly to eliminate artifacts from impuri- ties. Most significantly, the electrolyte in the cell used to generate the hydrogen to be liquef~ecl was replacecl by fresh alkaline solution. Brickwoclcle literally threw the baby out with the bath water. The dihycirogen procluced from fresh alkaline solution is clepletec! in deuterium. The Raleigh clis- tillation of this liquic! hydrogen brought the deuterium con-

OCR for page 363
HAROLD CLAYTON UREY 373 tent back to about natural abundance. As more and more water is added to the electrolytic cell to replace that elec- trolyzed, the deuterium abundances rise to the natural abun- dance level. THERMODYNAMIC PROPERTIES OF ISOTOPIC SUBSTANCES Urey's Nobel address was titled "Some Thermodynamic Properties of Hydrogen and Deuterium." The first part cov- ered the discovery of deuterium. Two-thirds of the address dealt with the differences in the thermodynamic properties of isotopes and the feasibility of isotope separation based on these differences. By the time Urey initiated his work on deuterium, calculation of the thermodynamic properties of ideal gases from spectroscopic data had been placed on a firm foundation. Such calculations are particularly simple when one compares the differences in behavior of isotopic substances. Under the assumption of the Born-Oppenheimer approximation, the large enthalpy changes from the differ- ence in the minima of the potential energies of products and reactants in a chemical reaction vanish for isotopic exchange reactions. Thus, Urey and Rittenberg calculated the differences in the degrees of dissociation of HCl~g) and DCl(g) and HI(g) and DI(g), respectively. They con- firmed their calculations with experiments on HI(g) and DI(g). Gould, Bleakney, and H. S. Taylor confirmed the Urey-Rittenberg calculations on the disproportionation of HD into H2 and D2. The success of statistical mechanics to predict differences in the chemical properties of hydrogen and deuterium led Urey and Greiff to extend the method to isotopomers of polyatomic molecules of carbon, nitro- gen, oxygen, and sulfur. For each of these elements, Urey and Greiff found exchange reactions with enrichment fac- tors in the range from ~ to 4 percent at room temperature. The predicted enrichment factors led Urey and Greiff to

OCR for page 363
402 BIOGRAPHICAL MEMOIRS oxygen isotopes oi6 Old in stone meteorites. [. Am. Chem. Soc. 56:2601-9. 1935 With L. A. Weber and M. H. Wahl. Fractionation of the oxygen isotopes in an exchange reaction. [. Chem. Phys. 3:129. With M. H. Wahl. Vapor pressures of the isotopic forms of water. [. Chem. Phys. 3:411-14. Some thermodynamic properties of hydrogen and deuterium. In Le Prix Nobel en 1934, pp. 1-10. Stockholm: Kungl. Baklryckenet. Also published in Angew. Chem. 48:315-20. With L. l. Greiff. Isotopic exchange equilibria. [. Am. Chem. Soc. 57:321-27. With G. K. Teal. The hydrogen isotope of atomic weight two. Rev. Mod. Phys. 7:34-94. 1936 With A. H. W. Aten, in On the chemical differences between nitro- gen isotopes. Phys. Rev. 50:575. With G. E. MacWood. Raman spectra of the deuteriomethanes. i. Chem. Phys. 4:402-6. With A. H. W. Aten, fir., and A. S. Keston. A concentration of the carbon isotope. i. Chem. Phys. 4:622-23. With G. B. Pegram and I. R. Huffman. The concentration of the oxygen isotopes. i. Chem. Phys. 4:623. 1937 With T. I. Taylor. The electrolytic and chemical-exchange methods for the separation of the lithium isotopes. J. Chem. Phys. 5:597-98. With l. R. Huffman, H. G. Thode, and M. Fox. Concentration of NO by chemical methods. J. Chem. Phys. 5:856-68. 1938 Chemistry and the future. Science 88:133-39. With M. Cohn. Oxygen exchange reactions of organic compounds and water. /. Am. Chem. Soc. 60: 679-87. With I. Roberts. The exchange of oxygen between benzil and water and the benzilic acid rearrangement. J. Am. Chem. Soc. 60:880-82.

OCR for page 363
HAROLD CLAYTON UREY 403 With I. Roberts. Esterification of benzoic acid with methyl alcohol by use of isotopic oxygen. {. Am. Chem. Soc. 60:2391-93. With H. G. Thode and I. E. Gorham. The concentration of Ni5 and S34. /. Chem. Phys. 6:296. With T. I. Taylor. Fractionation of the lithium and potassium iso- topes by chemical exchange with zeolites. [. Chem. Phys. 6:429-38. 1939 The separation of isotopes. In Recent Advances in Surface Chemistry and Chemical Physics, pp. 73-87. Washington, D.C.: American Asso- ciation for the Advancement of Science. With K. Cohen. Van der Waals' forces and the vapor pressures of ortho- and parahydrogen and ortho- and paradeuterium. [. Chem. Phys. 7:157-63. With I. Roberts. Kinetics of the exchange of oxygen between ben- zoic acid and water. {. Am. Chem. So c. 61:2580. With I. Roberts. Mechanisms of acid catalyzed ester hydrolysis, es- terification, and oxygen exchange of carboxylic acids. [. Am. Chem. Soc. 61:2584. Separation of isotopes. In Reports on Progress in Physics, vol. 6, pp. 48- 77. London: The Physical Society. 1940 With C. A. Hutchison, Jr., and D. W. Stewart. The concentration of Ci3. f. Chem. Phys. 8:532-37. Separation of isotopes by chemical means. [. Wash. Acad. Sci. 30:277- 94. With G. A. Mills. The kinetics of isotopic exchange between carbon dioxide, bicarbonate ion, carbonate ion and water. i. Am. Chem. Soc. 62:1019-26. 1942 With E. Leifer. Kinetics of gaseous reactions by means of the mass spectrometer. The thermal decomposition of dimethyl ether and acetaldehyde. J. Am. Chem. Soc. 64:994-1001. With I. Kirshenbaum. The differences in the vapor pressures, heats of vaporization, and triple points of nitrogen (14) and nitrogen ~ 15 ~ and of ammonia and trideuteroammonia. I. J. Chem. Phys. 10:706-17.

OCR for page 363
404 BIOGRAPHICAL MEMOIRS 1943 With A. F. Reid. The use of the exchange between CO2, H2CO3, HCO3 ion and H2O for isotopic concentration. [. Chem. Phys. 11 :403-12. 1945 With l. D. Brandner. Kinetics of the isotopic exchange reaction between carbon monoxide and carbon dioxide. [. Chem. Phys. 13:351-62. The atom and humanity. Science 102:435. 1946 Methods and objectives of the separation of isotopes. Pro c. Am. Philos. Soc. 90:30-35. Atomic energy in international politics. Foreign Policy Rep. 22:82-91. 1947 The thermodynamic properties of isotopic substances. /. Chem. So c. (London) 1947:562-81. 1948 Oxygen isotopes in nature and in the laboratory. Science 108:489-96. 1950 With C. R. McKinney, l. M. McCrea, S. Epstein, and H. A. Allen. Improvements in mass spectrometers for the measurement of small differences in isotope abundance ratios. Rev. Sci. Instr. 21:724- 30. The structure and chemical composition of Mars. Phys. Rev. 80:295. - 1951 With H. A. Lowenstam, S. Epstein, and C. R. McKinney. Measure- ments of paleotemperatures and temperatures of the upper cre- taceous of England, Denmark, and the southeastern United States. Bull. Geol. Soc. Am. 62:399-416. With S. Epstein, R. Buchsbaum, and H. A. Lowenstam. Carbonate- water isotopic temperature scale. Bull. Geol. Soc. Am. 62:417-26. Cosmic abundances of the elements and the chemical composition of the solar system. Am. Sci. 39:590-609.

OCR for page 363
HAROLD CLAYTON UREY 405 The origin and development of the earth and other terrestrial plan- ets. Geochim. Cosmochim. Acta 1:209-77. The social implications of the atomic bomb. Sci. Educ. 30:189-196. 1952 The Planets. New Haven, Conn.: Yale University Press. On the early chemical history of the earth and the origin of life. Proc. Natl. Acad. Sci. U. S.A. 38:351-63. The origin and development of the earth and other terrestrial plan- ets: a correction. Geochim. Cosmochim. Acta 2:263-68. Chemical fractionation in the meteorites and the abundance of the elements. Geochim. Cosmochim. Acta 2:269-82. The abundances of the elements. Phys. Rev. 88:248-52. 1953 With H. Craig. The composition of the stone meteorites and the origin of the meteorites. Geochim. Cosmocham. Acta 4:36-82. Chemical evidence regarding the earth's origin. In XIIth Congress for Pure and Applied Chemistry: Plenary Lectures, pp. 188-214. The deficiencies of elements in meteorites. Mem. So c. R. Sci. Liege 14:481-94. 1955 On the origin of tektites. Proc. Natl. Acad. Sci. U.S.A. 41:27-31. The cosmic abundances of potassium, uranium and thorium and the heat balances of the earth, the moon and Mars. Proc. Natl. Acad. Sci. U.S.A. 41:127-44. Distribution of elements in the meteorites and the earth and the origin of heat in the earth's core. Ann. Geophys. 11:65-74. Origin and age of meteorites. Nature 175:321. 1956 Diamonds, meteorites and the origin of the solar system. Astrophys. J. 124:623-37. With H. E. Suess. Abundances of the elements. Rev. Mod. Phys. 28:53- 74. Regarding the early history of the earth's atmosphere. Bull. Geol. So c. Am. 67:1125-28.

OCR for page 363
406 BIOGRAPHICAL MEMOIRS The origin and significance of the moon's surface. Vistas Astron. 2:1667-80. 1957 Boundary conditions for theories of the origin of the solar system. Prog. Phys. Chem. Earth 2:46-76. 1958 With H. E. Suess. Abundance of the elements in planets and mete- orites. Handb. Phys. 51:296-323. The atmospheres of the planets. Handb. Phys. 52. Composition of the moon's surface. Z. Phys. Chem. (N.F.) 16:346-57. Some observations on educational problems in the United States with particular reference to mathematics and science. School Sci. Math. March: 168-72. 1959 With S. L. Miller. Organic compound synthesis on the primitive earth. Science 130:245-51. With S. L. Miller. Origin of life (reply to letter by S. W. Fox). Science 130:1622-24. 1960 The origin and nature of the moon. Endeavor 19:87-99. The moon. In Science in Space, a report by the Space Science Board, National Academy of Sciences, pp.185-97. Washington, D.C.: National Academy of Sciences. The planets. In Science in Space, a report by the Space Science Board, National Academy of Sciences, pp. 199-217. Washington, D.C.: National Academy of Sciences. 1961 With N. Kokuku and T. Mayeda. Deuterium content of minerals, rocks and liquid inclusions from rocks. Geochim. Cosmochim. Acta 21 :247-56. On possible parent substances for the C2 molecules observed in the Alphonsus crater. Astrophys. f. 134: 268-69. Criticism of Dr. B. Mason's paper on The Origin of Meteorites. J. Geophys. Res. 66:1988-91.

OCR for page 363
HAROLD CLAYTON UREY 407 The dynamic nature of the atmosphere. In The Air We Breathe A Study of Man and His Environment, ed. S. M. Farber and R. H. L. Wilson, pp. 9-20. Springfield, Ill.: Charles C. Thomas. 1962 With V. R. Murthy. The time of the formation of the solar system relative to nucleosynthesis. Astrophys. f. 135:626-31. Evidence regarding the origin of the earth. Geochim. Cosmochim. Acta 26: 1-13. Origin of the lifelike forms in carbonaceous chondrites. Nature 193:1119- 33. Lifelike forms in meteorites. Science 137:623-28. Origin of tektites. Science 137:746-48. The origin of the moon and its relationship to the origin of the solar system. In The Moon, ed. Z. Kopal and Z. K. Mikhailov, pp. 133-48. New York: Academic Press. 1963 With V. R. Murthy. Isotopic abundance variations in meteorites. Science 140:385-86. The origin and evolution of the solar system. In Space Science, ed. D. P. LeGalley, pp. 123-68. New York: John Wiley & Sons. The origin of organic molecules. In Nature of Biological Diversity, ed. i- M. Allen, pp. 1-13. New York: McGraw-Hill. 1964 A review of atomic abundances in chondrites and the origin of meteorites. Rev. Geophys. 2:1-34. With E. C. Anderson and M. W. Rowe. Potassium and aluminum-26 contents of three bronzite chondrites. [. Geophys. Res. 69:564-65. The role of man in space. In Bioastronautics Fundamental and Prac- tical Problems, vol. 17, ed. W. C. Kaufman, pp. 61-64. North Holly- wood, Calif.: Western Periodicals. With S. L. Miller. Extraterrestrial sources of organic compounds and the origin of life (in Russian). In Problems of Evolutionary and Technical Biochemistry, pp. 357-69. Moscow: Science Press. 1965 With R. L. Heacock, G. P. Kuiper, E. M. Shoemaker, and E. A.

OCR for page 363
408 BIOGRAPHICAL MEMOIRS Whitaker. Ranger VII (Part II). Experimenters' Analyses and In- terpretations, pp. 1-154, Technical Report No. 32-700, {et Pro- pulsion Lab-NASA. 1966 Chemical evidence relative to the origin of the solar system. Mon. Not. R. Astron. Soc. 131: 199-223. The capture hypothesis of the origin of the moon. In The Earth- Moon System, ed. B. G. Marsden and A. G. W. Cameron, pp. 210- 12. New York: Plenum Press. With R. L. Heacock, G. P. Kuiper, E. M. Shoemaker, and E. A. Whitaker. Rangers 8 and 9 (Part II). Experimenters' Analyses and Interpretations. Technical Report No. 32-800, let Propulsion Lab-NASA. Observations on the Ranger VIII and IX Pictures, pp. 339-61. Tech- nical Report No. 32-800. let Propulsion Lab-NASA. Observations on the Ranger VII Pictures. Technical Report No. 32- 700. Jet Propulsion Lab-NASA. With I. R. Arnold. Biological materials in carbonaceous chondrites. In Biology and the Exploration of Mars, ed. C. S. Pittendrich, W. Vishniac, and J. Pearman, pp. 114-24. Washington, D.C.: National Academy of Sciences. 1967 Study of the Ranger pictures of the moon. Proc. R. Soc. London, Ser. A 296:418-31. The abundance of the elements with special reference to the iron abundance. (Harold Jeffreys Lecture). J. R. Astron. Soc. 8:23-47. Parent bodies of the meteorites and the origin of chondrules. Icarus 7:350-59. The origin of the moon. In Mantles of the Earth and Terrestrial Plan- ets, ed. S. K. Runcorn, pp. 251-60. London: John Wiley & Sons. 1968 With K. Marti. Surveyor results and the composition of the moon. Science 161:1030-32. The origin of some meteorites from the moon. Naturwissenschaften 55:49-57. The problem of elemental abundances. In Origin and Distribution of

OCR for page 363
HAROLD CLAYTON UREY 409 the Elements, ed. L. H. Ahrens, pp. 207-53. Oxford: Pergamon Press. Dalton's influence in chemistry. In John Dalton and the Progress of Science, ed. D. S. L. Cardwell, pp. 329-44. Manchester: Manches- ter University Press. 1969 Early temperature history of the moon. Science 165:1275. With G. I. F. MacDonald. Geophysics of the moon. Science 5: (5) :60- 66. With B. Nagy. Organic geochemical investigations in relation to the analyses of returned lunar rock samples. In Life Sciences and Space Research VII, pp.31-45. Amsterdam: North-Holland. Birth and growth of the oceans. In Oceanography, The Last Frontier, ed. R. C. Vetter, pp.31-44. Forum Series, Voice of America, U.S. Information Agency, Washington, D.C., broadcast for October 1969. 1970 With K. Marti and G. W. Lugmair. Solar wind gases, cosmic-ray spallation products and the irradiation history. Science 167:548- 50. With B. Nagy, C. M. Drew, P. B. Hamilton, V. E. Modzeleski, M. E. Murphy, W. M. Scott, and M. Young. Organic compounds in lu- nar samples: pyrolysis products, hydrocarbons, amino acids. Sci- ence 167:770-73. With B. Nagy, M. Scott, V. E. Modzeleski, L. A. Nagy, M. Drew, W. S. McEwan, J. E. Thomas, and P. B. Hamilton. Carbon compounds in Apollo 11 lunar samples. Nature 225:1028-32. With M. E. Murphy, V. E. Modzeleski, B. Nagy, W. M. Scott, M. Young, C. M. Drew, and P. B. Hamilton. Analysis of Apollo 11 lunar samples by chromatography and mass spectrometry. Pyroly- sis products, hydrocarbons, sulfur and amino acids. Proceedings of the Apollo 11 Lunar Science Conference, vol. 2, pp. 1879-90. 1971 With B. Nagy, I. E. Modzeleski, V. E. Modzeleski, M. A. Jabbar Mohammed, L. A. Nagy, W. M. Scott, C. M. Drew, I. E. Thomas, .

OCR for page 363
410 BIOGRAPHICAL MEMOIRS R. Ward, and P. B. Hamilton. Carbon compounds in Apollo 12 lunar samples. Nature 232:94-98. Was the moon originally cold? Science 172:403-5. A review of the structure of the moon. Proc. Am. Philos. Soc. 155:67- 73. 1972 . With K. Marti. Lunar basalts. Science 176:117-19. With D. M. Anderson, K. Biemann, L. E. Orgel, {. Oro, T. Owen, G. P. Shulman, and P. Toulmin III. Mass spectrometric analysis of organic compounds, water and volatile constituents in the atmo- sphere and surface of mars: the Viking Mars Lander. Icarus 16:111- 38. Abundance of the elements. Ann. N.Y. Acad. Sci. 194:35-44. The origin of the moon and solar system. In The Moon, ed. S. K. Runcorn and H. C. Urey, pp. 429-40. Dordrecht, Holland: Reidel. Maria Goeppert Mayer (1906-1972~. Year Book Am. Philos. Soc. pp. 234-36. Evidence for objects of lunar mass in the early solar system and for capture as a general process for the origin of satellites. Astrophys. Space Sci. 16:311-23. 1973 Cometary collisions and geological periods. Nature 242:32-33. With V. E. Modzeleski, I. E. Modzeleski, M. A. Tabbar Mohammed, L. A. Nagy, B. Nagy, W. S. McEwan, and P. B. Hamilton. Carbon compounds in pyrolysates and amino acids in extracts of Apollo 14 lunar samples. Nat. Phys. Sci. 242:50-52. With S. K. Runcorn. A new theory of lunar magnetism. Science 180:636- 38. 1974 Evidence for lunar type objects in the early solar system. In High- lights of Astronomy, ed. G. Contopoulos, vol 3, pp. 475-81. Comment on winning the Nobel Prize. New Sci. 64:10-17. 1975 With S. L. Miller and J. Oro. Origin of organic compounds or~ the primitive earth and in meteorites. [. Mol. Evol. 9:59-72.

OCR for page 363
FI A R O L D C LAYT O N U R E Y 411 With H. Alfven. Testimony on the California nuclear initiative. En- ergy 1:105-8. 1977 With J. A. O'Keefe. The deficiency of siderophile elements in the moon. Philos. Trans. R. Soc. London Ser. A 285:569-75. With I. Oro and S. L. Miller. In Energy Conversion in the Context of the Origin of Life, ed. R. Buvet et al., pp. 7-19. Amsterdam: North- Holland. r

OCR for page 363