An evaluation was made of the use of NaK as the primary coolant for the SNAP-2 system. Pumping-power limitations based on the mercury Rankine cycle are analyzed. Problems pertinent to any design-specification modifications are reviewed.

Samples of grade A Monel snd grade A nickel were subjected statically in a single reactor to an undiluted atmosphere of gaseous fluorine at pressures up to one atmosphere absolute and temperatures up to 1500 deg F. The grade A Monel was conservatively estimated to have consumed at least 40 times as much fluorine as grade A nickel during the entire period of the investigation. Samples of fused alpha Al/sub 2/O/sub 3/, alpha -Al/sub 2/O/sub 3/- MgO spinel, and alpha -Al/sub 2/O/sub 3/-NiO--nickel cermet were exposed to undiluted fluorine at one atinosphere absolute pressure at temperatures of 1340 and 1500 deg F. Results indicated that the alpha -Al/sub 2/O/sub 3/ is as good as the Ni in the region of 1300 deg F. Grade A nickel samples coated with nickel fluoride filins of 37,000 and 74,000 A, respectively, were exposed to an absolute pressure of gaseous UF/sub 6/ of 12 cm of Hg at temperatures of 1000 and 1800 deg F. (W.L.H.)

Sample fuel elements consisting of a ceramic core in stainless-steel cladding were prepared by tamping powder into the cladding snd then hot isostatically pressing the assembly. High-density cores and an excellent mechanical bond between the core and the cladding were obtained. (auth)

The major events in the mechanical phase of the Power Reactor fuels reprocessing program during June were: 1. Feasibility of shearing of fuel elements without disassembly has been demonstrated in tests using porcelain-loaded prototype fuel elements. 2. Further work with the Manco shear was not deemed tb be advisable since permission has been granted to use another shear for cutting UO{sub 2}-loaded fuel elements. 3. Necessity to strip the windows in Building 3048, to sandblast, and repaint them has seriously disrupted occupancy of the cell by July 1. Start of installation probably will not be before August 1. 4. A cold SRE element should be received during July which will permit a direct look a t the problems associated with processing of these irradiated fuel elements. 5. Concurrence with AEC, Atomics International, and ORNL people on the fabrication of a poisoned carrier was obtained and all criteria for the carrier were released and the design was completed. 6. A decision was made to install and use a 24-inch Ty-Sa-Man saw which is on hand and was originally purchased for use in the Segmenting Facility for the SRE reprocessing. This will be used instead of the multipurpose saw to allow more …

Approximately 16 to 18 liters of isopropyl alcohol in a 20-liter glass carboy in a floor type hood were ignited by infrared heat lamps used to heat the carboy and contents. A technician received several minor lacerations on the hand. (C.H.)

The solubility and conductivity of cerium(III) salts (as stand-ins for plutonium(III) salts) in dimethylsulfoxide, acetonitrile, ethylenediamine, and dimethylformamide were investigated to evaluate these systems as possible electroplating baths. The system dimethylsulfoxide-cerium chloride is the most promising for electrodeposition of cerium at a mercury cathode. (auth)

Developments in the production of various graphite products and data on the properties, outgassing, and radiation resistance of various graphites are reviewed. (C.J.G.)

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.)

Centrifugal-casting techniques were investigated as a method of producing hollow cylindrical extrusion billets of aluminum-35 wt.% uranium. Among the variables evaluated were melt temperature, mold and pouring-spout configurations, mold speed, and method of pouring. With the equipment employed it was found that the best castings were produced utilizing a pouring temperature of 2400 ction prod- , a heavy-walled steel cylinder rotating between 700 and 900 rpm for the mold and a bottom-pouring technique employing a retractable pouring spout. Sound, nonporous billets 26 in. long and 5 in. in diameter were produced with a yield after machining of over 75% of the original charge. The major losses occurred in the pouring spout-and-cup asserably. This loss is relatively unaffected by the casting length; and, therefore, castings of greater length than 26 in. should result in even greater recoveries. (auth)

A method for determining the concentration of Li/sup 6/ in aqueous solution was tested using the nuclear reactions Li/sup 6/(n, alpha )H and O/sup 16/(H/sup 3/,n)F/sup 18/. Annihilation gamma radiation of induced 1.87-hr F/ sup 18/ radioactivity was counted with a welltype scintillation counter, and the radioactivity per millimole of lithium was found to be independent of lithium concentration below about 0.2 moles/liter. The sensitivity limit for detecting lithium is less than 0.1 micromole (0.0075 micromole Li/sup 6/). (auth)

The results of a parametric study on a gas cooled reactor are repotrtd. The system considered was a heliumcooled, UC/sup 2/-fueled arrargement with fuel assemblies consisting of clusters of long cylindrical elements, each element covered by a stainless steel jacket. The axial power distribution was assumed to be a chopped cosine having an axial peak-to-average power of 1.32. The three parameters of interest in the study were the diameter of coolant channel, pressure drop through core, and pumping Ppwer expended. The analysis is presented for the central channel. (auth)

A concentration cell electrode was installed in a fritted glass surface and was used to measure the surface KCl concentration while water was being transpired through the surface into a mixed tank of 0.1 M KCl. The results from the first Fluorox run made with crude UF/sub 4/ showed that 85.3% of the theoretical amount of UF/sub 6/ was accounted for, with 17.9% being collected in cold traps and the remainder being consumed in various side reactions. Installation was completed of apparatus to study the electrolytic removal of nickel on an engineering scale from concentrated HRT fuel solution. An extremely low yield stress of 0.02 lb/sq ft was measured for a thoria-urania slurry containing 2.5 wt.% Al/sub 2/O/sub 3/ and spherical particles of 1.7 micron mean diameter. Preliminary data on the rate of uranium sorption on Dowex 21K from sulfate solutions were correlated with a simple spherical diffusion model. Laboratory scale studies to determine the effect of reflux time, HNO/sub 3/ concentration, and air sparge on chloride removal from APPR-type Darex dissolver product showed that an air sparge is definitely beneficial in chloride removal. Preliminary cyclic cleaning tests showed that boiling 25% caustic solution was adequate for cleaning type F …

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The national laboratory concept, laboratory objectives, the staff, research facilities. research activities, and administration are discussed in general terms and a financial statement is given. Fairly detailed accounts are given for the research programs in the fields of physics, accelerator development, instrumentation, applied mathematics, chemistry, nuclear engineering, biology, and medicine. (W.D.M.)

Preliminary experiments were conducted to evaluate the use of the nuclear reactions Li/sup 6/ (n, alpha )H/sup 3/ and O/sup 16/(H/sup 3/,n) F/sup 18/ to determine the thickness of oxide films on metals. Sheets of thin paper and of aluminum, imbedded in powdered LiF, were irradiated with pile neutrons at a flux of 6 x 10/sup 11/ n/cm/sup 2//sec and counted with an end-window proportional counter. A saturation activity of 1.87 hr F/sup 18/ of 150 dis/min per microgram of oxygen was observed in the paper, but radioactivity due to impurities masked F/sup 18/ in the aluminum. It is concluded that a 1 A (0.01 mu gm/cm/sup 2/) oxide film thickness may be measured by a neutron irradiation at a flux of 10/sup 14/ n/cm/sup 2//sec but chemical separation of induced radioactivity from the bulk metal is essential. (auth)

The operation of the freeze-seal type sodium pump requires a shaft freeze-seal capable of retaining sodium. A prototype two-coolant-region freeze seal for application on HNPF sodium pumps was designed and constructed. It was tested under environmental conditions to determine its operating characteristics and sodium retaining capabilities. (auth)

The toroidal version of the hard-core pinch tube is created by levitating a ring conductor inside a toroidal shell. The magnitude of induced H/ sub theta / necessary for levi-tation is small in terms of field strengths normally desired for energetic pinches. In a 3-in. glass-and-copper toroid of square cross section a 3/4-in. hollow copper ring has been levitated with a 60- cycle current of 3 kiloamperes. A 12-in stainless steel tube of round cross section is being built. The stability of nearvacuum field hard-core configurations is best investigated in toroidal geometry. At high power levels and low plasma densities, the conventional toroidal stabilized pinch'' is subject to an anomalous plasma energy leakage to the wall, which cannot be explained by the observed ultraviolet radiation alone. A critical question is, therefore, whether the relative stability of some hard-core pinches, as reflected by the smoothness and reproducibility of magnetic probe traces, is reflected by an improved containment of the plasma en-ergy leading to high temperature. A toroidal hard-core tube is also useful in studying the nature of the nonhydromagnetic instabilities observed in the linear inverse stabilized pinch.'' The presence and condition of electrodes appear to have a substantial effect on the …

The compatibility of zirconium diboride, boron carbide, and boron nitride with type 304 stainless steel was evaluated as a function of temperature (1000 to 12OO deg C), time (1-3 hr). Appropriate loadings of the boron compounds and stainless steel powder were blended and fashioned into a compact powder metallurgically. Each compact was roll clad into a plate and subsequently heat treated at a temperature equal to the initial sintering temperature. Metallographic examination of the fabricated and heat-treated plates demonstrated that none of the systems was metallurgically stable. The instability was generally manifested by the interaction of the discrete boron compounds with the matrix and precipitation of a hypothetically boron-rich phase throughout the stainless steel matrix material. Of the three compounds, boron nitride was relatively the most stable in a stainless steel matrix under the test conditions. (auth)

The nil-ductility-transitaion (NDT) temperature, as defined by the Naval Research Laboratory drop-weight test, was determined on the A212B carbon-silicon steel used in the pressure vessel of the N. S. Savannah reactor. Correlations were made with the Charpy-V-notch impact energy at NDT. Specimens taken at two different thickness locations from material used in the ipper closure head of the reactor vessel yielded NDT temperatures of 0 to 20 deg F which correspond to Charpy-V-notch impact energies of 11 to 19 ft-lb. Testing of as-received material used in the lower closure head indicated that the NDT temperature was 50 deg F which was equivalent to an average CharpyV-notch impact energy of 12 ft-lb. After normalizing and stress-relieving thin material, in order to more closely approximate the final ccndition of the reactor vessel, NDT was reduced to less than 10 deg F. (auth)

The toxicological properties of beryllium and compounds of beryllium are briefly reviewed, together with the historical developmert of the recommendations for maximum permissible beryllium air concentrations. The application of the enclosure technique for the control of beryllium hazards is described. Emphasis is placed on the design objectives of partial and total enclosures and the related function of auxiliary components. Monitoring procedures used to evaluate the performance of enclosures are discussed. (auth)

Design of a system to punch binary data from a pulse height analyzer on paper tape concurrent with the printing of decimal information is presented. (J.R.D.)

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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 …