Report issued by the Bureau of Mines on the motor-fuels sold during the winter of 1947-1948. Characteristics of the fuel samples obtained are listed. This report includes tables, graphs, and a map.

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.

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 184-inch cyclotron. So far as the present observations are concerned both of these series begin with isotopes of protactinium (atomic number 91), although progenitors with higher atomic numbers are to be expected and will possibly be produced and identified. These protactinium isotopes are Pa{sup 227} and Pa{sup 228} formed by d,7n and d,6n reactions respectively.

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 data and (5) spectroscopic data. The salient point is that the characteristic oxidation state (i.e., the oxidation state exhibited by the member containing seven 5f and presumably also by the member containing fourteen 5f electrons, curium and element 103) is the III state, and the group is placed in the periodic table on this basis. The data also make it possible to give a suggested table of electronic configurations of the ground state of the gaseous atom for each of the elements from actinium to curium inclusive.

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.

Report presenting data on freezing point for UNH - NH₄NO₃ - HNO₃ - H₂O Systems. A range of concentrations of systems was used and data is presented.

Following the shutdown of the B Pile in March 1946 a method was devised for monitoring the sub-critical reactivity such that any significant change in neutron flux would be detected. This report summarizes the status of the unit until its start up in July 1948.

This report is a short communication concerning the performance of pilot plant sand filters at Building 292-B at Hanford Atomic Products Operation. (VC)

This document details activities at the Hanford Works during the month of June 1948.

This report covers work done by the Pile Engineering Groups and work done on special assignments. Topics covered include: slug blistering and corrosion; graphite allocation to DR pile; slug molding; segmental discharge; Van Stone corrosion; flow laboratory modifications; downcomer at B pile; downcomer at D pile; annealing of pile graphite; replacement of pile atmosphere with CO{sub 2}; unit motion; beta experiment; can opening; slug annealing; new technical building, 300 area; and ruptured slugs.

This memorandum discusses briefly and approximately the two extreme programs which could be followed in the production of Ta{sup 182}: the use of present available excess reactivity, and the use of a pile, continuing no U{sup 238}, expressly to produce Ta{sup 182}. Use of lesser amounts of enriched material would achieve lesser production rates. The cost in fissionable material per gram of active isotope would remain approximately the same.

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, specific activity measurement, and calorimetric determination of half life showed the curium to be relatively pure. The absorption of light of various wave-lengths by an aqueous solution of Cm(III) is described, and some physical effects of the radiation from the curium are noted.

This is the University of California, Radiation Laboratory progress report for June 15-July 15, 1948. It discusses the following: (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 Departments; (9) Medical Physics; and (10) Health Physics and Chemistry.

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From introduction: "The discovery of element number 96, curium, was realized by the preparation and identification of the isotope Cm-242 by G. T. Seaborg, R. A. James and A. Ghiorso by cyclotron bombardment of Pu-239 with helium ions."

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The following document describes some studies of the radioactive isotopes of cerium and lanthanum lying on the light or neutron-deficient side of stability.

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This document is a de-classified July 1948 General Chemistry Progress Report from Monsanto Chemical`s Mound facility. Detailed discussions of numerous studies of Postum compounds are included in this report, and experimental data on various chemical and physical properties of these compounds are given.

During the course of a research problem involving hydrofluoric acid it became necessary to filter concentrated hydrofluoric solutions to remove various solid materials. The search for a suitable filter media finally led to the use of a commercially manufactured plastic material known as ``Sponge Teflon`` (polytetrafluoroethylone) which is produced by the DuPont Company. This material, which comes in 1/8 in. sheets, is used primarily as a gasket material in acid lines, and is impervious to all acids, including hydrofluorle acid.