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Variable Metric Method for Minimization

Description: A method is presented for numerically determining local minima of differentiable functions of several variables. In the proeess of locating each minimum, a matrix is determined which characterizes the behavior of the function about the minimum. For a region in which thc function depends quadratically on the variables, no more than N iterations are required, where N is the number of variables. By suitable choice of starting values and without modification of the procedure, linear constraints can be imposed upon the variables. (auth)
Date: May 1, 1959
Creator: Davidon, W. C.
Partner: UNT Libraries Government Documents Department

SEMI-ANNUAL PROGRESS REPORT FOR THE PERIOD JANUARY 1960 THROUGH JUNE 1960

Description: Modifications were made in the Carlson and Banks procedure for the spectrophotometric determination of silicon in beryllium metal and oxide. The refractory oxide is dissolved directly in hydrofluoric acid. The identical procedure is used for metal after ignition to the oxide. Concentrations of beryllium over certain limits have a quenching effect on the fluorescence of the aluminum-Portachrome Blue Black R complex. The determination of trace amounts of aluminum in beryilium can be carried out despite this quenching effect by the method of standard addition. Samples of plutonium sulfate tetrahydrate prepared 9 to 12 months earlier were under investigation to determine the suitability of this compound as a primary analytical standard of plutonium. The compound was determined experimentally to contain four molecules of water of crystallization. Plutonium sulfate tetrahydrate was found to lose a major portion of its water of crystallization when heated at 115 ts C. Indications, but no conclusive evidence, of the existence of another intermediate hydrate of plutonium(IV) sulfate, were found. Microscopic examination of 1-year-old crystals of Pu(S0/sub 4/)/sub 2/.4H/sub 2/0 shows no evidence of the effect of any alpha radiolysis on the water of crystallization. Continued exposure to a fluctuating atmosphere caused no apparent changes in crystal structure or weight. Heating Pu(SO/sub 4/)/sub 2/.4H/sub 2/0 to 325 ts C produced a dehydrated salt of weight equivalent to the formula, Pu(S0/sub 4/)/sub 2/. This material, although slightly hygroscopic, can be readily dried at 120 ts C and appears to be satisfactory for further investigation of its suitability as an alternate primary stand ard of plutonium. A method is presented for the rapid determination of milligram quantities of sulfateiIn pure plutonium sulfates. Plutonium is adsorbed on a cation resin and an acidimetric titration is made of the displaced hydrogen ion which is equivalent to the sulfate content of the ...
Date: January 1, 1961
Creator: Rodden, C.J.
Partner: UNT Libraries Government Documents Department

ISOTOPIC MASS SPECTROMETRY OF THE ELEMENTS

Description: The Analytical Mass Spectrometry Section at Oak Ridge National Laboratory has, for many years, been determining relative isotopic abundances from solid samples. Thus, useful analytical mass spectrometer experience with every pertinent element has been obtained. These include the 55 polyisotopic elements as well as products of irradiation and fission. The techniques used are summarized in this report. A separate page for each element lists preferred compound, loading of sample, manner of obtaining a stable ion beam, and solutions of special problems. (auth)
Date: December 17, 1963
Creator: Spitzer, E.J. & Sites, J.R., comps.
Partner: UNT Libraries Government Documents Department

Dry Bearing Endurance Test for the Service Machine: Experimental Gas-Cooled Reactor

Description: The concept of operating bearings and gears unlubricated in a helium environment was questioned as to fundamental soundness. Tests were made to determine if immediate gross failure occurs. A bearing of standard manufacture was operated in helium for 42 hr. A high degree of gradual wear was encountered. No gross or sudden failures were found. (W.L.H.)
Date: September 29, 1960
Creator: Flippen, B. H.
Partner: UNT Libraries Government Documents Department

REACTIVITY OF SUBSTITUTION ELEMENTS

Description: A method is sought for predicting reactivity differences between fuel elements attached to control absorbers and fixed fuel elements. The approach described is based on a logic that is approximate, and which should be subjected to experimental check. (auth)
Date: January 19, 1959
Creator: Murray, R.L.
Partner: UNT Libraries Government Documents Department

FLAME PHOTOMETRIC DETERMINATION OF IRON. PARTS I, II, III AND IV

Description: An investigation was conducted to compare the flame emission spectrum of Fe as recorded by the Beckman DU and the ORNL flame spectrophotometers. It was found that the ORNL instrument is best suited to the application. Optimum operating conditions are described as well as results of investigations to determine interferences. (J.R.D.)
Date: May 1, 1959
Creator: Menis, O
Partner: UNT Libraries Government Documents Department

STATIC STRESS DETERMINATIONS IN SALT, SITE COWBOY

Description: An investigation was made to determine the stress field in the salt dome and the stress concentrations on the surface of the small (12-ft diameter) sphere. For the most part, the apparatus and techniques used in the investigation are new and have not been described in other reports. Therefore the theory, concepts, apparatus, and some of the lists made to determine the reproducibility of the apparatus are described briefly. (W.L.H.)
Date: July 29, 1960
Creator: Merrill, R.H.
Partner: UNT Libraries Government Documents Department

AN ANNOTATED BIBLIOGRAPHY OF ANALYTICAL METHODS FOR ALKALI METALS

Description: A total of 107 abstracts is presented on analytical methods for alkali metals, as a part of a program for the evaluation of the performance of the primary cold trap from the Enrico Fermi Reactor. The abstracts are arranged into sections dealing with general aspects; sampling and dissolution techniques; and determination of uncombined alkali metal, oxygen, carbon, hydrogen, nitrogen, and other impurities. (D.L.C.)
Date: March 1, 1964
Creator: Garcia, E.E. & LaMont, B.D.
Partner: UNT Libraries Government Documents Department

DISSOLVED OXYGEN--INDIGO-CARMINE METHOD

Description: The indigo-carmine method is a simple, rapid, accurate colorimetric procedure for determining small amounts of dissolved oxygen in water (0 to 50 ppm). A solution of reduced indigo-carmine dye added to a water sample is oxidized by the presence of any dissolved oxygen and changes color. The change in color of the dye is directly proportional to the amount of dissolved oxygen present in the sample and can be determined by using a Johnson color comparator. (W.L.H.)
Date: November 1, 1959
Creator: Santoro, P.F. & Powell, A.S.
Partner: UNT Libraries Government Documents Department

PERFORMANCE TEST OF A TWO-COOLANT-REGION SODIUM PUMP SHAFT FREEZE-SEAL

Description: The operation of the freeze-seal type sodium pump requires a shaft freeze-seal capable of retaining sodium. A prototype two-coolant-region freeze seal for application on HNPF sodium pumps was designed and constructed. It was tested under environmental conditions to determine its operating characteristics and sodium retaining capabilities. (auth)
Date: July 15, 1959
Creator: Streck, F.O.
Partner: UNT Libraries Government Documents Department

EUROCHEMIC ASSISTANCE PROGRAM: COMMENTS BY ICPP, DATED FEBRUARY 25, 1959, ON QUESTIONS LISTED IN ORNL-CF-59-1-75

Description: The handiing of interface j-ettings in waste solution processing and determination of mono-, di-, and tri-butyl phosphates in process solvents are discussed. Decontamination procedures used in ICPP are outlined. Evaporator deentrainment at ICPP is discussed. Information on Lapp pulse units and on continuous dissolution is presented. (D.L.C.)
Date: November 16, 1960
Creator: Weech, M.E.
Partner: UNT Libraries Government Documents Department

ALUMINUM DETERMINATION IN REACTOR COOLING WATER

Description: ABS>A method for determination of submicrogram quantities of Al in reactor cooling water by neutron activation analysis is described. Data obtained in analyses of samples from the OKR and the Bulk Shielding Reactor are included. (J.R.0.)
Date: September 1, 1958
Creator: Emery, J.F. & Leddicotte, G.W.
Partner: UNT Libraries Government Documents Department