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Georgia Iron Deposits, Cherokee, Bartow, Floyd, and Polk Counties (In Two Parts): Part II

Description: Report issued by the Bureau of Mines over exploration of iron ore deposits in four counties in Georgia. The work accomplished during the summer of 1945 in these deposits is presented. The report describes physical features, geology, and characteristics of the ore samples collected. This report includes tables, maps, and illustrations.
Date: January 1948
Creator: Robertson, Almon F.
Partner: UNT Libraries Government Documents Department
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United States Earthquakes, 1948

Description: Report discussing earthquake activity in the United States during 1948. The report is broken down by regions and has sections for specific earthquakes.
Date: 1948
Partner: UNT Libraries Government Documents Department
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Some Excitation Functions of Bismuth

Description: Excitation functions have been measured, using a 38-Mev alpha-beam and a 19-Mev deuteron beam for the following reactions: Bi({alpha},2n)At{sup 211}, Bi({alpha},3n)At{sup 210}, Bi(d,p)Ra E, Bi(d,n)Po{sup 210}, and Bi(d,3n)Po{sup 209}. The results are summarized in Figs. 4 and 5 and Tables I and II. A new isotope of astatine, At{sup 210}, has been identified; this isotope has a half life of 8.3 hr., decaying by K-capture to Po{sup 210} with the emission of a 1.0-Mev gamma-ray and a few conversio… more
Date: October 10, 1948
Creator: Kelly, E.L. & Segre, E.
Partner: UNT Libraries Government Documents Department
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Experiments of the Effect of Atomic Electrons on the DecayConstant of Be7

Description: In an attempt to detect a possible influence of the atomic electrons on the radioactive decay constant of Be{sup 7} they have measured {lambda}{sub Be}-{lambda}{sub BeO} and found (-3.0 {+-} 1.8) 10{sup -4} {lambda}{sub Be}. They describe also a method to measure mean lives of radioactive substances in a time short compared with the mean life.
Date: July 1, 1948
Creator: Segre, Emilio & Wiegand, Clyde
Partner: UNT Libraries Government Documents Department
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The Path of Carbon in Photosynthesis

Description: The dark fixation of carbon dioxide by green algae has been investigated and found to be closely related to photosynthesis fixation. By illumination in the absence of carbon dioxide followed by treatment with radioactive carbon dioxide in the dark, the amount fixed has been increased ten to twenty fold. This rate of maximum fixation approaches photosynthesis maximum rates. The majority of the radioactive products formed under these conditions have been identified and isolated and the distributi… more
Date: March 8, 1948
Creator: Calvin, M. & Benson, A. A.
Partner: UNT Libraries Government Documents Department
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Progress Report No. 62 June 1-15, 1948

Description: This paper reports on the following programs: (1) 184-inch Cyclotron Program; (2) 60-inch Cyclotron Program; (3) Synchrotron Program; (4) Linear Accelerator Program; (5) Experimental Physics; (6) Theoretical Physics; (7) Isotope Separation Program; (8) Chemistry; and (9) Medical Physics.
Date: June 30, 1948
Partner: UNT Libraries Government Documents Department
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Artificial Collateral Chains to the Thorium and ActiniumFamilies

Description: The authors have produced and identified two new series of alpha-particle emitting radioactive elements; one is a 'collateral' branch of the actinium (4n + 3) radioactive family and the other is collateral to the thorium (4n) family. The series are of considerable interest in that they are the first whose early members lie on the neutron deficient side of beta stability. They have been produced in high yield of irradiation of thorium with deuterons of energy about {sup 80}Mev in the Berkeley 18… more
Date: July 1, 1948
Creator: Ghiorso, A.; Meinke, W. W. & Seaborg, G. T.
Partner: UNT Libraries Government Documents Department
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Monthly Progress Report No. 60 for April 1948

Description: This report gives a short summary of each of the following programs: (1) 184-inch Cyclotron Program; (2) 60-inch Cyclotron Program; (3) Synchrotron Program; (4) Linear Accelerator Program; (5) Experimental Physics; (6) Theoretical Physics; (7) Chemistry; (8) Medical Physics; and (9) Health Physics and Chemistry.
Date: May 1, 1948
Partner: UNT Libraries Government Documents Department
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The Ion-Exchange Separation of Zirconium and Hafnium

Description: In the course of a rather cursory examination of the elution of tetra-positive ions from the cation exchange resin Dowex 50 with hydrochloric acid solutions, the authors have discovered a very effective method of separating zirconium from hafnimu. In view of the great labor involved in preparing even reasonably pure hafnium compounds by existing methods, they feel that this procedure will prove very valuable to those interested in obtaining hafnium compounds free of zirconium. Although the cond… more
Date: October 11, 1948
Creator: Street, Kenneth, Jr. & Seaborg, Glenn T.
Partner: UNT Libraries Government Documents Department
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Paramagnetic Suseptibilities and Electronic Structure of AqueousCations of Elements 92 to 95

Description: Magnetic susceptibilities per gram atomic weight of elements 92 to 95 in most of their oxidation states were measured on 0.1 ml of solution which was 0.007 to 0.09 M in heavy element. The values obtained (all paramagnetic) in c.g.s. units x 10{sup 6} were: U(IV), 3690; Np(VI), 2060; Np(V), 4120; Np(IV), 4000; Pu(IV), 1610; Pu(III), 370; Am(III), 720. The results could be interpreted only on the basis of electronic configurations 5f{sup n}, even though susceptibilities were generally lower than … more
Date: November 12, 1948
Creator: Howland, Jerome J. & Calvin, Melvin
Partner: UNT Libraries Government Documents Department
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N-17, A Delayed Neutron Emitter

Description: The decay scheme of a 4.2 second neutron emitter has been investigated in detail. Chemical and physical evidence shows that it is N{sup 17}, which emits beta rays to a broad excited state of O{sup 17}, which then breaks up into a neutron plus O{sup 16}. The energy spectrum of the neutrons is determined by measuring the energies of the O{sup 16} recoils in a proportional counter. The neutrons have a most probable energy of 0.9 Mev, a 'half width' of less than .5 Mev, and an upper limit of about … more
Date: November 5, 1948
Creator: Alvarez, L. W.
Partner: UNT Libraries Government Documents Department
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Electronic Structure of the Heaviest Elements

Description: All of the available evidence leads to the view that the 5f electron shell is being filled in the heaviest elements giving rise to a transition series which begins with actinium in the same sense that the rare earth or 'lanthanide' series begins with lanthanum. Such an 'actinide' series is suggested on the basis of evidence in the following lines: (1) chemical properties, (2) absorption spectra in aqueous solution and crystals, (3) crystallographic structure data, (4) magnetic susceptibility da… more
Date: July 14, 1948
Creator: Seaborg, G. T.
Partner: UNT Libraries Government Documents Department
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Monthly Progress Report No. 58 for February 1948

Description: This is a monthly progress report on the following programs: (1) 184-inch Cyclotron; (2) 60-inch Cyclotron; (3) Synchrotron; (4) Linear Accelerator; (5) Experimental Physics; (6) Theoretical Physics; (7) Isotope Research; (8) Chemistry; (9) Medical Physics; and (10) Health Physics and Chemistry.
Date: February 1, 1948
Partner: UNT Libraries Government Documents Department
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The Path of Carbon in Photosynthesis II. Amino Acids

Description: The radioactive amino acid's synthesized from C{sup 14}O{sub 2} by green algae both in the light and in the dark after CO{sub 2}-free preillumination have been separated and identified using paper chromatography and radioautography. The radioactive amino acids identified were aspartic acid, alanine and smaller amounts of 3- and 4-carbon amino acids. This finding as well as the total absence of radioactive glutamic acid substantiates the mechanism for reduction of CO{sub 2} previously postulated… more
Date: May 25, 1948
Creator: Stepka, W.; Benson, A. A. & Calvin, M.
Partner: UNT Libraries Government Documents Department
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Path of Carbon in Photosynthesis III

Description: Although the overall reaction of photosynthesis can be specified with some degree of certainty (CO{sub 2} + H{sub 2}O + light {yields} sugars + possibly other reduced substances), the intermediates through which the carbon passes during the course of this reduction have, until now, been largely a matter of conjecture. The availability of isotopic carbon, that is, a method of labeling the carbon dioxide, provides the possibility of some very direct experiments designed to recognize these interme… more
Date: June 1, 1948
Creator: Benson, A. A. & Calvin, M.
Partner: UNT Libraries Government Documents Department
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Monthly Progress Report No. 59 for March 1948

Description: This monthly progress report covers the following programs: (1) 184-inch Cyclotron; (2) 60-inch Cyclotron; (3) Synchrotron; (4) Linear Accelerator; (5) Experimental Physics; (6) Theoretical Physics; (7) Chemistry; (8) Medical Physics; and (9) Health Physics and Chemistry.
Date: March 1, 1948
Partner: UNT Libraries Government Documents Department
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The Path of Carbon in Photosynthesis IV. The Identity and Sequencefo the Intermediates in Sucrose Synthesis

Description: The synthesis of sucrose from C{sup 14}0{sub 22} by green algae has been investigated and the intermediates separated by the method of paper chromatography. It is shown that sucrose is the first free sugar appearing during photosynthesis. It is apparently formed by condensation of the glucose-I-phosphate and a fructose phosphate. A series of radioautographs of paper chromatograms of extracts from plants which have photosynthesized for different periods of time has been prepared. The results ind… more
Date: December 14, 1948
Creator: Calvin, M. & Benson, A.
Partner: UNT Libraries Government Documents Department
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An Isotope Effect in a Simple Chemical Reaction

Description: It has been found that the carbon dioxide obtained from the decarboxylation of singly-carboxyl labeled malonic acid is impoverished in the C{sup 14} label and that the acetic acid formed is correspondingly enriched.
Date: July 13, 1948
Creator: Yankwich, Peter E. & Calvin, Melvin
Partner: UNT Libraries Government Documents Department
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Progress Report No. 65 Aug. 15-Sept. 15, 1948

Description: This is a progress report on the following: (1) 184-inch Cyclotron Program; (2) 60-inch Cyclotron Operation; (3) Synchrotron Program; (4) Linear Accelerator Operation; (5) Experimental Physics; (6) Theoretical Physics; (7) Isotope Separation Program; (8) Chemistry; (9) Medical Physics; and (10) Health Chemistry and Physics.
Date: September 15, 1948
Partner: UNT Libraries Government Documents Department
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P Division monthly report, November 1948

Description: This progress report discusses activities at the P Division for the month of November 1948. All piles operated at 275 megawatts (MW) throughout the month except for outages listed under Area Activities in this report and except that F Pile operated at a reduced level during the first half of the month. This operation at reduced level was incident to the leaking process tube reported last month. A total of 81.4 tons of metal was discharged from the piles during the month. The 300 Area canned a t… more
Date: December 20, 1948
Creator: Lee, Edward P.
Partner: UNT Libraries Government Documents Department
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Diameter Measurements of Slugs Before and After Prolonged Heat Treatment

Description: Abstract: "Diameter measurements of 25 slugs taken before and after a prolonged heat treatment showed no evidence of differences that would indicate blistering. The average effects of the treatment was different for the various slugs. Large differences in diameter measurements between slugs. Large differences in diameter between slugs and significant differences between indices and positions were found."
Date: February 16, 1948
Creator: Bennett, Carl A. & Lane, J. J.
Partner: UNT Libraries Government Documents Department
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