Report issued by the Bureau of Mines over the progress made in emergency mine communications. The results of testing done on low-frequency radio communication are presented. This report includes tables, graphs, illustrations, and photographs.

This report gives a short summary of each of the following programs: (1) 184-inch Cyclotron Program; (2) 60-inch Cyclotron Program; (3) Synchrotron Program; (4) Linear Accelerator Program; (5) Experimental Physics; (6) Theoretical Physics; (7) Chemistry; (8) Medical Physics; and (9) Health Physics and Chemistry.

The radioactive amino acid's synthesized from C{sup 14}O{sub 2} by green algae both in the light and in the dark after CO{sub 2}-free preillumination have been separated and identified using paper chromatography and radioautography. The radioactive amino acids identified were aspartic acid, alanine and smaller amounts of 3- and 4-carbon amino acids. This finding as well as the total absence of radioactive glutamic acid substantiates the mechanism for reduction of CO{sub 2} previously postulated by members of this laboratory.

Description of the standards used by the electrical power industry for the measurement of the electrical quantities.

The following report examines the fission counter, fission plates and activation results of the neutron energy distribution in the center of the Los Alamos plutonium reactor.

The operation of the Fast Reactor is considered in terms of normal equilibrium conditions and normal shut-down. The proposed loading, control rod adjustment and subsequent "floating" operation are discussed. Safety devices and interlocks are described. Temperature and reactivity changes are examined with respect to various system failures, phase changes, and "flashing" of the reactor. Slow changes due to faulty slug cooling are also considered. The calculations were initially based upon 10 kw operation. Performance tests of the mercury system now indicate that 20-kw operation may be feasible.

The following report describes procedures taken to utilize the photelometer to procure the most rapid and reliable determinations, but the goal of the tests presented was to create satisfactory dispersions of particles to analyze.

Operation of the 100F pile is reported on. Ongoing construction is described; detailing population and occupancy. Visitors and the Schenectady report are discussed. A copy of the June 4 letter from Carleton Shugg to Carrol L. Wilson pertaining to flooding of the Columbia and Yakima rivers is included.

This is the University of California, Radiation Laboratory monthly progress report for May 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.

None

This progress report discusses progress on oxidation-reduction studies, including polarography, as well as the Uranium-complex formation including electrical transport and spectro-photometric work. This report covers the work done in the period of February of 1945.

The following report analyzes the hydrolytic behavior of cerium and compares them with the actinides of uranium and plutonium.

The following report presents data and conclusions from investigations of the chemical properties of elements 95 (americium, Am) and 96 (curium, Cu) by means of tracer techniques.

Report discussing experiments that were performed to determine whether amino acids in urine could be used as a test of subtle uranium poisoning.

None

"This appendix presents a description of the loading equipment, the tracking procedure, and the results of tests and observations made during and after the traffic tests on the asphalt stability test section. Analyses of the test results are also included" (p. 1).

"This report presents the results of laboratory and field tests conducted by the Corps of Engineers to develop a method for the design and construction control of asphalt paving mixtures. The investigation consisted of: (a) the selection of a test apparatus and the performance of laboratory studies to develop techniques and procedures; (b) the construction of a test section and the performance of traffic tests with 15,000 and 37,000-lb single and 60,000-lb dual wheel loads to obtain design criteria; and (c) additional laboratory work to adjust the test procedures to the design criteria" (p. 1).

None

A theoretical discussion of the formation and steady state kinetic behavior of metal complexes is provided.

This quarterly progress report describes four programs namely (1) The Metabolic Properties of Plutonium and Allied Materials (2) Biological studies of radiation effects, (3) Biological effects of radiation from external and internal sources, and (4) Health Physics and Chemistry. Progress for each program has been separately indexed and abstracted for the database.

Report presenting an investigation to determine the effects of forward movements of transition on the section characteristics of a 12-percent-thick low-drag airfoil section with a 0.24-chord sealed plain aileron. Section lift and aileron section hinge-moment and seal-pressure characteristics were determined at a specific Reynolds number for aerodynamically smooth surfaces and with fixed transition at two different points.

"The effects of outdoor weathering for 2 years and of an accelerated weathering test on the weight, dimensional stability, and flexural properties of selected reinforced plastics were investigated. The results of all tests, both in this report and the previous report (NACA TN No. 1240), indicate that none of the laboratory aging tests correlated with outdoor weathering with respect to all properties and all materials" (p. 1).

"A flight investigation in natural icing conditions was conducted by the NACA to determine the effect of ice accretion on airplane performance. The maximum loss in propeller efficiency encountered due to ice formation on the propeller blades was 19 percent. During 87 percent of the propeller icing encounters, losses of 10 percent or less were observed" (p. 1).

From Summary: "An investigation to determine the effectiveness of icing protection afforded by air-heating hollow steel unpartitioned propeller blades has been conducted In the NACA Cleveland icing research tunnel. The propeller used was a production model modified with blade shank and tip openings to permit internal passage of heated air. Blade-surface and heated-air temperatures were obtained and photographic observations of Ice formations were made with variations In icing intensity and heating rate to the blades. For the conditions of Icing to which the propeller was subjected, it was found that adequate ice protection was afforded with a heating rate of 40 1 000 Btu per hour per blade."