Search Results

Advanced search parameters have been applied.
open access

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
open access

Isolation and Propterties of Curium

Description: The isolation of curium, element number 96, in relatively pure form has been accomplished. A method, involving a solvent extraction process, is given for the purification of americium from lanthanum and other ions. The discovery of a higher oxidation state of americium led to a method of separating americium from curium. Separation of the two elements was also accomplished by use of ion exchange resins. The details of the isolation of curium are given; the results of the spectrographic analysis… more
Date: July 28, 1948
Creator: Werner, L.B. & Perlman, I.
Partner: UNT Libraries Government Documents Department
open access

The Isolation and Properties of Curium

Description: The isolation of curium, element number 96, in relatively pure form has been accomplished. A method, involving a solvent extraction process, is given for the purification of americium from lanthanum and other ions. The discovery of a higher oxidation state of americium led to a method of separating americium from curium. Separation of the two elements was also accomplished by use of ion exchange resins. The details of the isolation of curium are given; the results of the spectrographic analysis… more
Date: August 1, 1948
Creator: Werner, Louis B.
Partner: UNT Libraries Government Documents Department
open access

The solution chemistry of polonium (Ad Interim Report)

Description: This document is a March 1949 Ad Interim Report from the Mound Laboratory on the solution chemistry of polonium. A consideration of the valences of the elements of the Group VI-A would indicate that the oxidation states of -2, 2, 4, and 6 might be expected for polonium. From the decrease in stability of the hydrides of these elements with increase in atomic number, one would expect that the compound H{sub 2} Po would be very unstable and that the oxidation state of -2 would not occur in solutio… more
Date: March 22, 1949
Creator: Haring, M. M.
Partner: UNT Libraries Government Documents Department
open access

ELEMENT 98

Description: Definite identification has been made of an isotope of the element with atomic number 98 through the irradiation of Cm{sup 242} with 35 Mev helium ions in the Berkeley Orocker Laboratory 60-inch cyclotron. The isotope which has been identified has an observed half-life of about 45 minutes and probably has the mass number 244. The observed mode of decay of the 98{sup 244} is through the emission of alpha-particles, with energy about 7.1 Mev, which agrees with predictions, and other consideration… more
Date: February 27, 1950
Creator: Thompson, S. G.; Street Jr., K.; Ghiorso, A. & Seaborg, G. T.
Partner: UNT Libraries Government Documents Department
open access

Chemistry Division, Section C-I, Summary Report for January, February and March 1950

Description: Information is presented in threc main sections: nuclear and radiochemistry. physical and organic chemistry, and process chemistry. Included is an investigation of naturally occurring Pu for isotopes other than Pu/sup 239/ , an examination of Mallinckrodt wastes for Ac/sup 227/ the half life of Pa/sup 240/ the cross section of Np /sup 237/ and a study of Np isomers, studies of various Tc and Re compounds, coincidence of interference in a pulse analyzer, absorption of neutrons in a sphere. separ… more
Date: June 1, 1950
Creator: Osborne, D. W.
Partner: UNT Libraries Government Documents Department
open access

The New Element Californium (Atomic Number 98)

Description: Definite identification has been made of an isotope of the element with atomic number 98 through the irradiation of Cm{sup 242} with about 35-Mev helium ions in the Berkeley Crocker Laboratory 60-inch cyclotron. The isotope which has been identified has an observed half-life of about 45 minutes and is thought to have the mass number 244. The observed mode of decay of 98{sup 244} is through the emission of alpha-particles, with energy of about 7.1 Mev, which agrees with predictions. Other consid… more
Date: June 19, 1950
Creator: Thompson, S. G.; Street Jr., K.; Ghiorso, A. & Seaborg, G. T.
Partner: UNT Libraries Government Documents Department
open access

Conference on Quantum-Mechanical Methods in Valence Theory

Description: Proceedings from the Conference on Quantum-Mechanical Methods in Valence Theory organized into six sections: Atomic and Molecular Problems, The Link with Chemical Valence Concepts, Intermolecular and Nonbonded Interatomic Forces, Transcending the Primitive Approximations, Mathematical Developments, and Integrals. Some papers include additional discussion from other participants. Table of contents starts on page iii.
Date: 1952
Partner: UNT Libraries Government Documents Department
open access

Hot semiworks Redox studies

Description: The separations Hot Semiworks at the Hanford Atomic Products Operation was built in order to: (1) develop optimum conditions for the economic operation of the Redox and TBP plants, (2) procure engineering design data which would allow the specification of process equipment required for new processes such as Purex, (3) provide facilities for the study of future process and engineering problems on a semiworks scale employing radioactive process solutions, and (4) provide facilities for immediate … more
Date: January 27, 1954
Creator: Evans, T. F. & Tomlinson, R. E.
Partner: UNT Libraries Government Documents Department
open access

Estimated Upper Bounds to the Half-Life of Thermal Decomposition of Ammonia, Hydrogen, Methane, and Propane

Description: An estimate was made of the upper bound for the half-time of dissociation at 100 atm for ammonia, methane, and propane at 2500 deg K and hydrogen at 5000 deg K. In each case a unimolecular reactron in the homogeneous gas phase was chosen as most suitable for this purpose. Slater's theory has been used to estimate the necessary frequency factors. The upper bounds to the half- time for dissociation range from 3 x 10/sup -7/ to 6 x 10/sup -6/ sec. Extrapolation of decomposition rate data obtained … more
Date: August 1, 1955
Creator: Herschbach, D.
Partner: UNT Libraries Government Documents Department
open access

Oxidation and Contamination Reactions of Niobium and Niobium Alloys

Description: Niobium was found to react linearly with air (600 to 1200 deg c) and with oxygen (400 to 1400 deg c). At 1400 deg c, a very rapid reaction with oxygen was observed. Contamination hardening during oxidation was attributed to diffusion of oxygen into the metal from the predominantly Nb/sub 2/O/sub 5/ scale. Alloying effects could be correlated with relative ionic size and valence of the alloy addition and with properties of the alloy-element oxides. Additions with smaller ionic size or higher val… more
Date: February 1, 1959
Creator: Klopp, W. D.; Maykuth, D. J.; Sims, C. T. & Jaffee, R. I.
Partner: UNT Libraries Government Documents Department
open access

Progress Relating to Civilian Applications During February 1959

Description: Measurements of the thermal conductivity of unirradiated U and UO/sub 2/ were completed. An evaluation is being made of the creep properties of annealed and 15% cold-worked Zircaloy-2 at elevated temperatures in order to determine the suitability of Zircaloy-2 for process tubing in the NPR. Single crystals of highpurity Mo are being grown for irradiation studies. Research to identify factors affecting irradiation-induced volume changes sn graphite by means of sink- float density measurements wa… more
Date: March 1, 1959
Creator: Dayton, R. W. & Tipton, C. R., Jr.
Partner: UNT Libraries Government Documents Department
open access

PROGRESS RELATING TO CIVILIAN APPLICATIONS DURING JULY 1959

Description: A study of the creep properties of 15% cold-worked and annealed Zircaloy- 2 sheet at 290, 345, and 400 deg C is continuing. Data are presented on the corrosion in bightemperature water of defected natural-U fuel cores extrusion clad with Zircaloy-2. The composition and temperature of the Al--U--Ni ternary eutectic in high-Al alloys are being determined. The study of neutron-activation analysis of cement raw materials was continued. Work continued on the study of radiation-induced changes in pol… more
Date: August 1, 1959
Creator: Dayton, R.W. & Tipton, C.R. Jr.
Partner: UNT Libraries Government Documents Department
open access

SOME PHOTOCHEMICAL AND PHOTOPHYSICAL REACTIONS OP CHLOROPHYLL ANDITS RELATIVES

Description: The solution photochemistry of chlorophyll and chlorophyll analogs is described. Many cases of electron transfer to or from the porphyrin macrocycle have been found, but in no case has any very large degree of energy storage been achieved. Because of the very rapid back-reaction for products with a {Delta}F of approximately -30 kcal, some solid state models in which such an energy storage might be achieved are described and their possible relation to the natural photosynthetic apparatus is give… more
Date: April 11, 1960
Creator: Calvin, Melvin
Partner: UNT Libraries Government Documents Department
open access

BIO-ORGANIC CHEMISTRY QUARTERLY REPORT. December 1962 throughFebruary 1963

Description: This report covers the following titles: (1) A versatile solvent to replace phenol for the paper chromatography of radioactive intermediary metabolites; (2) Chromatography of plant lipids on alumina paper; (3) Quinone and pigment composition of chloroplasts and quantasomes from Spinacea oleracea; (4) The lipid composition of chloroplast lamellae from Spinacea oleracea; (5) Metal chelates and photochemistry of flavins; (6) Photoinduced ESR in some solutions of organic electron donors and accepto… more
Date: March 29, 1963
Partner: UNT Libraries Government Documents Department
open access

Variation of the Half-Wave Potential of Organic Compounds With pH. Report No. 78

Description: From 19th International Union of Pure and Applied Chemistry Congress, London. A systematic introduction is presented to the subject of the variation with pH of the polarographic half-wave potential, which is probably the most readily measured electrochemical energetic parameter of organic compounds. Emphasis is placed on (a) the types of relationships observed for both reversible and irreversible electrode processes, (b) the mathematical formulation of these relationships, (c) the structural, m… more
Date: June 21, 1963
Creator: Elving, P. J.
Partner: UNT Libraries Government Documents Department
open access

Mixtures of Metals With Molten Salts

Description: A review is presented of various types of solutions of metals in molten salts, especially in their own molten halides. With relatively little reference to the older literature, the progress made in the last 20 years is discussed. Roughly, the solutions are classified into two groups: The metal may retain, to some degree, its metallic properties in the solution, or it may lose them through strong interaction with the salt solvent. The alkali-metal systems are typical examples of the former type,… more
Date: August 15, 1963
Creator: Bredig, M. A.
Partner: UNT Libraries Government Documents Department
open access

Compounds in the Binary Phase Diagrams of the Monovalent Chlorides With the Multivalent Chlorides

Description: The phase-diagram literature was surveyed to the end of 1960. Information about the binary systems of monovalent with multivalent chlorides was observed. Compounds of double chlorides occurring in these systems are listed in tabular form together with the available structural information. (auth)
Date: November 1, 1963
Creator: Gut, R.; Iberson, E. & Gruen, D. M.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen