Techniques involving the use of high-intensity short-duration light pulses have been applied t o the study of the kinetics of photoconductivity in films of metal-free phthalocyanine. These experiments, in conjunction with measurements of steady-state photoconductivity, are consistent with the following scheme. The principal route for the formation of charge carriers is via the first excited singlet state, although the lowest triplet state can, t o some extent, contribute to charge - carrier production. The mobility of the carriers is low and is concentration-dependent, being lower at higher carrier concentration. The decay of the photocurrent is the result of a diffusion-limited bimolecular recombination, with a capture radius of approximately one molecular diameter. The experiments indicate that carriers produced thermally in the dark do not interact with light-produced carriers.

The addition of ortho-chloranil to the surface of films of metal-free phthalocyanine has been found (a) to increase the dark conductivity of such films by as much as 10{sup 7}, (b) to increase the steady-state photoconductivity by as much as 10{sup 5}, and (c) to result in the formation of unpaired electrons whose concentration decreases reversibly as a result of illumination. These systems exhibit a light-induced polarization, the phthalocyanine layer becoming more positive with respect t o the ortho-chloranil layer. Kinetic studies demonstrate that, upon illumination, a single process (time constant = 40 seconds) results in the increase in conductivity, the decrease in unpaired spins, and the increase in polarization. The results are consistent with the following scheme. An electron transfer from phthalocyanine to ortho-chloranil occurs in the dark at room temperature, producing holes in the phthalocyanine layer and ortho-chloranil negative ion radicals (high conductivity, ESR signal). Illumination results in the transfer of an electron from an excited phthalocyanine molecule to the ortho-chloranil negative ion, producing further phthalocyanine holes and ortho-chloranil double-negative ion (increase in conductivity, increase in polarization, decrease in ESR signal). By equating spin concentration with charge - carrier concentration (phthalocyanine holes) it is possible to calculate a …

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This document details activities of the Fuels Preparation Department during the month of November 1959. (FI)

The objective of the test detailed in this report is to irradiate self-supported fuel elements under conditions of severity comparable in these expected for future loadings of this geometry, to attempt to determine the resistance to corrosion of cooled cladding, the effect of supports on cladding corrosion and coolant flow patterns, and the relative resistance to ``hot-spot`` type attack and rupture of ``projection`` fuel elements and rib supported elements. This test will authorize irradiation of four columns of self-supported and four columns of rib-supported I and E, 1.47% enriched fuel elements until two ruptures are sustained in each group on type demonstrates a significant factor of improvement in rupture resistance over the other.

The Expansion Study Task Force has evaluated several cases of Hanford reactor operation at power levels considerably higher than is presently obtained in the six older reactors. These higher power levels result in more rigorous operating conditions of temperature, heat flux, neutron flux, hydraulics, reactor control, etc. The purpose of this document, the various components of which were prepared by Process and Reactor Development Sub-Section personnel, is to assess the technical feasibility of operation under the proposed conditions, and to delineate those specific areas of development effort which may be necessary to provide adequate support for an expansion program.

Abstract: Tests were made on 24 simply supported, post-tensioned, end-anchored, prestressed concrete beams with and without web reinforcement.

For several years, a major category of fuel element failures has been the side corrosion type, characterized by localized accelerated fuel element jacket corrosion. Since it has been demonstrated {sup 1} that misalignment of fuel elements in a process tube will produce flow patterns and accelerated corrosion, termed ``hot spots``, failure to align the fuel elements in process tubes is considered a contributing factor in the production of side corrosion failures. Preliminary testing of both self-supporting and ``bumper`` fuel elements is underway. Data on the self-supporting fuel elements have demonstrated that the bridge-rail projections have sufficient support strength, do not of themselves create a corrosion problem and in actuality probably eliminate any hot-spot areas. Although one tube of bumper fuel elements in KW Reactor {sup 3} has been discharged, data are not as yet available. Potentially, the most sever corrosion conditions exist during the summer months when reactor inlet temperatures are high. It is desirable then, provided bumper fuel elements limit hot- spot corrosion, to evaluate the bumper concept for large scale use possibly by the summer of 1960. To accomplish this, a demonstration loading of the bumper type fuel elements must be underway by about July, 1959. The purpose …

The material covered are R and D, 2000 reactor and metallurgy program (production reactors, N-Reactor). Topics covered include operating schedules and production, fuel, engineering, safety, control, physics, etc.

"This bibliography lists selected articles on beryllium which have appeared in journals received in the library of the Lawrence Radiation Laboratory, Livermore, California and articles, reports, and books which have appeared in the following abstracting services between January, 1958 and August 1959."

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The apparatus and procedures that are to be used to fill the liquid metal system of the Pratt and Whitney Forced Convection Liquid Metal Inpile Loop are described. The liquid metal to be used is a mixture containing 56% Na and 44% K, which is a liquid at room temperature. In order to simplify the filling procedure at the reactor site, two containers, each of which contains exactly enough liquid metal to fill the experiment to the prescribed level, a fill dolly incorporating a purified helium system, and an evacuation system will be provided at the reactor site. After completion of the liquid metal transfer, the liquid metal fill tube will be crimped, cut, and seal welded. The liquid metal and helium systems will then be pressurized through the helium fill tubes, which will also be crimped, cut, and seal welded. Each tube seal weld will be inspected after completion of the weld by mass spectrometry leak check and dye penetrant fault detection

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Electron microscopy was used to supplement metallographic studies of bonds between Zircaloy-2 interfaces. Treated surfaces before bonding, and bonded sections made by a variety of techniques were examined. Electron micrographs of belt-abraded surfaces exhibited a consistent fine-scale roughness. Chemically pickled surfaces were nearly smooth regardless of prior treatment. Chemically pickled samples and a zirconium oxide-coated sample pressure bonded at 1500 F and 10,000 psi had pitting at bond lines that could have been due to voids or to contaminant at the interface which etchod out. The pitting was almost completely eliminated in one sample by pressing one hour at 500 F and 350,000 psi. This indicated that the bond-line pitting in these samples was due to voids at the interface. Zircaloy-2 samples pressure bonded after coating with carbon chromium, iron nickel, or tin etched in relief along the bond line, indicating the presence of contaminant at the interface. On the basis of the present investigation, it is proposed that grain growth across the interface in chemically pickled samples may have been inhibited by the presence of a thin contaminant film originally present on the Zircaloy surfaces. However, the poor grain-growth characteristics of chemically pickled samples may also be due in …

The following report presents neutron-flux measurements made with a concentric-cylinder element (Mark II) and includes axial, radial, and peripheral flux distributions.

In the preliminary stages of getting up a time-of-flight system for measuring neutron spectra from proton reactions, a study of the time dependence of the beam in the 86Inch Cyclotron was made. This study revealed the expected bunching of the protons to produce a short burst of beam on each cycle of the 13.4 Mc/s accelerating voltage. In addition to the 13.4 Mc/s structure, however, there was a 360 c/sec modulation of the beam pulses and a complicated pattern built upon that.

Equilibrium loading of uranium on Dowex 21K was studied in a sulfate system for uranium concentrations from 0.0005 to 0.005M, total sulfate concentrations of 0.045 to 0.6M, and sulfuric acid concentration of 0.020M. Loading data were fitted to Langmuir adsorption isotherms and Langmuir constants were evaluated. Resin was equilibrated with uranium feed solutions by flowing the feed through a shallow fixed bed of resin. (auth)

The study revealed the bunching of protons to produce a short beam burst on each cycle of the l3.4 Mc/sec accelerating voltage. In addition to the l3.4 Mc/sec structure, there was a 360 cps beam pulse modulation. Oscilloscope patterns are given which show: (l) the envelope of the r-f accelerating voltage; (2) 60 cps line voltage with time scale; (3) beam intensity; and (4) beam intensity at faster oscilloscope sweep. Apparently the beam intensity is critically dependent on the accelerating voltage, but is not a monotonic function of that voltage. (B.O.G.)

Studies were made to investigate the possibility of removing oxide impurities from Na-cooled reactor systems by cold trapping in conjunction with fill-drain tanks. (W.L.H.)

The purpose of the Transuranics Program is to develop separation processes for the transuranic elements, primarily those produced by long-term neutron irradiation of Pu/sup 239/. The program includes laboratory process development, pilot-plant process testing, processing of 10 kg of Pu/sup 239/ irradiated to greater than 99% burn-up for plutonium and americium-curium recovery, and processing the reirradiated plutonium and americium-curium fractions. The proposed method for processing highly irradiated plutonium is: (1) plutonium-aluminum alloy dissolution in HNO/sub 3/; (2) plutonium recovery by TBP extraction; (3) americium, curium, and rare-earth extraction by TBP from neutral nitrate solution; (4) partial rare-earth removal (primarily lanthanum) by americium-curium extraction into 100% TBP from 15M HNO/sub 3/; (5) additional rare-earth removal by extraction in 0.48M mono-2-ethylhexylphosphoric acid from 12M HCl; and (6) americium-curium purification by chloride anion exchange. Processing through the 100% TBP, 15M HNO/sub 3/ cycle can be carried out in the Power Reactor Fuel Reprocessing Pilot Plant. New facilities are proposed 15M HNO/ sub 3/ cycle can be carried out in the Power Reactor Fuel Reprocessing Pilot Plant. New facilities are proposed for laboratory process development studies and the final processing of the transplutonic elements. (auth)

A performance evaluation was made of a prototype liquid cooled freeze trap with sodium at 350 and 1000 deg F. The sodium freeze-off function was adequate for all test conditions encountered. The freeze-off occurred satisfactorily with the larger clearance provided by a test modification to provide 0.030 eccentricity to the rotating shaft. Turning the freeze-trap handle was successful in opening the unit for gas venting when 350 deg F sodium was used. For a seal formed with 1000 deg F sodium, 16 turns of the trap handle gave no measurable gas venting at pressures up to 30 psi. Melting out the seal opened the vent satisfactorily. All the major problems encountered during the test were mechanical and associated with the rotating feature of the unit. (M.C.G.)