Abstract: The rate of extraction of PuIV in either direction between benzene-TTA and aqueous HNO3 solutions is shown in the present study to be fast enough so that application of the chelate process to continuous operation should be feasible. This conclusion is based on two primary considerations: 1. The mechanism limiting the rate of extraction appears to be diffusion and not chemical-reaction-limiting. 2. The extraction may be controlled by adjustment of the system conditions to give almost any desired specifications of rate and/or equilibrium. A continuous process involving multiple extraction stages with a controlled pH gradient is proposed for obtaining maximum decontamination and plutonium recovery.

This summary of the research progress meeting on June 3, 1948 discusses the following topics: (1) Photomultipliers (L. Wouters); (2) Positive mesons (C.M.G. Lattes); and (3) Background work in 184-inch program (W. Panofsky).

This summary of the research progress meeting on June 10, 1948 discusses the following topics: (1) 184-inch cyclotron (J. Vale); (2) Slow neutrons in the shielding of the 184-inch cyclotron (W. Benson); and (3) Fission of thorium with alpha particles (A. Newton).

This summary of the research progress meeting on June 17, 1948 discusses the following topics: (1) Potassium 43 (R. Overstreet); (2) Recoils (A. Ghiorso); (3) M.I.T. accelerator conference (W. Panofsky); and (4) Cosmic rays (Prof. Louis Le prince - Ringuet, France)

This summary of the research progress meeting on June 24, 1948 discusses the following topics: (1) Spectrographic analysis of alpha active materials (J. Conway); and (2) Range energy determinations (Dr. R.L. Thornton, Mr. Walter Stephan and Mr. Walter Aron).

The following report is a quarterly report done by the Physics Division of the University of California's Radiation Laboratory, covering the period of February 1, 1948 to May 1, 1948. This report discusses general physics research and the development and operation of the accelerator.

A quarterly summary of reports that have been published on research being conducted at the University of California Radiation Laboratory

An outline is given for mismatch and delay measurements methods on air dielectric transmission line components, and techniques for square wave testing are outlined. Equipment design of the needed pulsers, attenuation and delay sections, and high speed oscilloscopes is disclosed. The final section of this report is devoted to measurements and how to analyze results

Secondary charge effects from a 10 kilovolt proton beam and their effect upon beam current measurement are investigated. A collector is designed for beam current metering of a 60 kilovolt proton beam by means of charge measurement and energy measurement.

The proper roof thickness to correspond with a given side wall thickness has been estimated fro experience with the 184 feet cyclotron, which has indicated that a roof of about 1 1/2 feet should accompany a wall of 5 feet, and a roof of 4 feet should accompany a wall of 15 feet. For the roof area involved, this should bring about the condition that down-scattered neutrons in the working areas are but a small fraction of the neutrons coming through the side walls.

Isotopes of americium and curium with mass numbers less than 242 have been produced by cyclotron bombardment techniques, and several of their nuclear properties have been investigated. The partial alpha half-lives of Am(239), Cm(241), and Cm(240) and the partial half-life for spontaneous fission of Cm(240) were measured. The alpha decay daughter of Cm(238) was found and evidence for the discovery of Am(237) (an -1 hour electron capture activity) and Cm(239) (an -10 hour electron capture activity) has been presented. An Appendix indicating the conditions for separation of the plus three actinides by selective elution from ion exchange resin with citric acid has been included.

The free streaming of neutrons in a cylindrical cavity is investigated. Using experimental data for the flux distribution along the walls, the direct beam hole loss and leakage into the target from the lattice is estimated for the MTA system.

In the past it was felt that the easiest way to treat a three group equation for a MTA lattice was to solve it without certain terms. This iterative procedure converged rapidly for a medium with depleted uranium fuel, and in fact, a second iteration was not needed.

Quarterly summary report of studies conducted through the University of California Radiation Laboratory. Some results reported in the report may be of a preliminary or incomplete nature.

A buncher and pre-accelerator for A-12 is described that has 360 degree acceptance and could handle a current of one ampere from a low voltage source.

Early in the design of the Mark I accelerator it was decided to install magnetic lenses in the drift tubes. A number of model magnets were constructed and tested to determine the best design for these lenses. This report includes only the results of the tests on the final models of the magnets that are designed for Mark I.

Quarterly progress on the metabolic properties of various materials, radiation chemistry, biological studies of radiation effects, health chemistry, health physics.

This is an extension of the results reported in UCRL-2203, where bore diameter is determined in a linear accelerator.

At high excitation energies, competition of proton and c-particle emission with neutron emission becomes important. For low excitation, the competition between Y-emission, neutron emission, and fission should be taken into account. To aid in the evaluation of this competition an experiment has been performed to measure the number and energy spectrum of the protons and c-particles emitted in the high energy bombardment of uranium with protons, deuterons, and c-particles.

Quarterly report of the Chemistry Division at the University of California Radiation Laboratory providing updates for each department about current findings and ongoing research.

Statistical methods were employed to measure relative values of electron loading and spark-over voltage for a large number of unoutgassed electrode materials. Test voltages up to 110 KV were employed in vacuum of the order of 10<sup>-7 mm Hg. All metals showed a square root dependence between spark-over voltage and spacing.

The following document describes how to determine the measurements of the optical density or absorption spectra of suspensions of micro-organisms.

This report follows the work on the Kjedahl digestion procedure in sealed tubes at 470 C. as well as analyzing factors influencing ammonia decomposition within these tubes.

Report discussing details of the design for the Bevatron at the University of California Radiation Laboratory. The Bevatron is a "6-billion-electron-volt (Bev) proton synchotron. This device will receive a 10-million-electron-volt (Mev) proton beam from a linear accelerator, and further accelerate a reasonable percentage of these protons, at a nominally constant radius of 600 inches, to a final energy greater than 6 Bev."