12,765 Matching Results

Search Results

Advanced search parameters have been applied.

Measurements of Small Amounts of H$sub 2$O in D$sub 2$O by Near-Infrared Absorption Spectroscopy

Description: The literature on the near-infrared and infrared absorption spectra of liquid H/sub 2/O and D/sub 2/O as well as other literature related to the determination of small amounts of one in the presence of the other was reviewed. Nearinfrared absorption techniques appear to be very convenient, rapid, and almost ideally suited for the determination of H/sub 2/O in the concentration range from 0 to 10% in D/sub 2/O. The absorption spectra of H/sub 2/O, D/sub 2/ O, (HDO), and of mixtures of H/sub 2/O in D/sub 2/O were obtained using a Cary Model l4 PM Recording Spectrophotometer. As expected. the H/sub 2/O was found to undergo very rapid and almost complete exchange to HDO, especially at relatively low H/sub 2/O concentrations. In agreement with some previously reported French and Japanese work, a relatively intense and very useful absorption band for HDO has been found at l.668 mu , and it is used for the determination. By the use of the procedure described. 0.5, 2, 4, and 7 wt.% H/sub 2/O in D/sub 2/O can be determined with respective approximate relative standard deviations of 7, 2, 1, and 0.7% when 1-cm absorption cells are used in conjunction with a pure D/sub 2/O reference liquid. (auth)
Date: December 1, 1958
Creator: Biggers, R. E.
Partner: UNT Libraries Government Documents Department

Spectrophotometric Determination of Microgram Quantities of Osmium With Diphenylcarbazide

Description: A method was developed for the spectrophotometric determination of 30 to 100 mu g of osmium. The osmium as OsO/sub 4/ is extracted with CHCl/sub 3/ and diphenylcarbazide is then added to the organic extract. A blue-violet reaction product is formed, the absorbancy of which is measured at 560 m mu . A suitable reagent concentration is from 3 to 5 ml of 0.2% diphenylcarbazide in a volume of 25 ml and the preferred solvent for the reagent is ethanol. Beer's law is followed over a range of 8 to 130 mu g of osmium with a coefficient of variation of about 4 After a 2-hr color-development period the molar absorbancy index is 31,300. Attempts to achieve reproducible measurements of absorbancy in less than 2 hr were unsuccessful. A study was made of the effects of foreign elements and only Ru(VIII) was found to interfere. (auth)
Date: June 1, 1959
Creator: Goldstein, G.
Partner: UNT Libraries Government Documents Department

NUCLEAR CHEMISTRY RESEARCH. Annual Progress Report

Description: The results of experiments and planned work of the Department of Chemistry, Arkansas University, in nuclear chemistry and physics, theoretical physics, and organic isotope chemistry are discussed. The absolute activation cross sections for 14.8-Mev neutrons were determined for a large number of isotopes, and a new isotope was found in the Fe/sup 54/(n,t) reaction. The (n,2p) reaction was studied in detail. A number of (n,He/sup 3/) and (n,t) reactions were studied. A literature survey (up to 1958) was made for cross sections of neutron-induced reactions around 14 Mev. The (n,p) reaction survey was continued up to date. The literature data have a large spread with factors of 2 to 10. Equations were derived from the (n,p) data giving the cross section as a function of atomic number and mass. The yields for U/sup 238/ 14-Mev fission were measured at mass numbers were studied. The theoretical aspects of molecular excitation resulting from beta decay of a constituent atom are being studied. Calculations were made on the wave functions of the ground state of the helium atom. The acid-catalyzed rearrangements of ketones were studied with both labeled and unlabeled compounds. No cyclic ketones were found to rearrange. The mechanism of the oxygen exchange between benzyl and substituted benzyl alcohols and water was studied with O/sup 18/ tracer. The oxygen exchange between water and benzophenones was also studied. The chlorine isotope effects in displacement reactions of benzyl and substituted benzyl chlorides with various nucleophiles were investigated; the results show a relation between isotope effect and reaction kinetic order. The C/sup 14/ isotope effect on the S/sub N/2' reaction of 3-chloro-1-butene-1-C /sup 14/ with diethylamine was measured. A preliminary measurement was made of the N/sup 15/ isotope effect in the Curtis rearrangement. (See also ORO-182.) (D.L.C.)
Date: January 1, 1961
Creator: Fry, A. & Fink, R.W.
Partner: UNT Libraries Government Documents Department

The 1A Hybrid Flowsheet

Description: A preliminary hybrid 1A flowsheet in which the extraction section operates substantially acid while the scrub section is acid deficient is presented. The effects of added nitric acid on the performance of the acid deficient 1A flowsheet are considered, and the need for control of the entering stream acidities in such flowsheets is evaluated. Data on batch-countercurrent decontamination and plutonium recovery are included. (J.R.D.)
Date: January 1, 1950
Creator: Coplan, B. V.; Davidson, J. K.; Hass, W. O. & Zebroski, E. L.
Partner: UNT Libraries Government Documents Department

Calculated Equilibrium Distributions for the Uranyl Nitrate - Tributyl Phosphate - Dilute Nitric Acid System for Temperatures Between 25 and 75 C

Description: Report discussing the "equilibrium uranium distribution between an aqueous nitric acid solution and a 30 per cent by volume solution of tributyl phosphate in a hydrocarbon diluent" (p. 2). This includes the necessary equations.
Date: August 12, 1960
Creator: Wilburn, N. P.
Partner: UNT Libraries Government Documents Department