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The electrical resistivities of polycrystalline samples of La, Pr, Nd, and Sm are reported in the temperature range 1.3 to 300 deg K. La exhibits a superconducting transition at 5.8 deg K. The curve for Pr has slope changes at 61 and 95 deg K. The Nd curve shows small jumps at 5 and 20 deg K. Sm shows slope changes at 14 and 106 deg K. (auth)

A review of the theories of electron paramagnetic resonance in biology is presented, including a discussion of the nature of the physical observation, followed by examples of materials of biological interest. Iq discussing these examples, information is presented in terms of the nature of the starting material under observation rather than the nature of the magnetic entities observed. The examples proceed from the simpler molecules of biological interest (metabolites, vitamins, cofactors) into the more complex materials (polymers, proteins, nucleic acids) toward cellular organelles (mitochondria, chloroplasts) and, finally, to whole cells, organisms and organs. The observation of photoinduced unpaired electrons in photosynthetic material is described and the various parameters controlling it are discussed. The basic observation is interpreted in terms of a primary photophysical act of quantum conversion.

The projection welded brazed closure is being studied as a possible alternate method of closing coextruded Zircaloy-2 clad uranium fuel elements for the NPR. This closure consists essentially of projection welding the Zircaloy-2 cap to the element cladding followed by a fast resistance heating of the cap and exposed uranium face under pressure to braze the cap to the uranium face. The work to date has been entirely on 0.593 inch OD rods and 1.050 inch OD by 0.500 inch ID tubular elements. This closure has the advantage that the entire closure is completed in less than 5 seconds on one machine and consequently the element is at a temperature which would be detrimental to the Zircaloy-2 cladding and uranium bond for a very short time. The amount of uranium removed for this closure is reduced by a factor of 10 over conventional braze closure methods with a substantial savings in uranium and acid milling time. A braze material which is not toxic can be used to bond the cap to the uranium.

Programming a computer that optimizes the beam in the Brookhaven AGS is discussed. Layout, method, and routines are given particular attention, and representative data cards are shown. (D.C.W.)

A graphical compilation is presented of atomic and molecular cross sections of interest to controlled thermonuclear research. The cross sections are shown, as a function of energy, for collision processes involving molecular ion dissociation, charge exchange, excitation, ionization, photoionization, scattering, energy loss, and recombination. Pertinent nuclear cross sections are also included. A bibliography is given covering the literature since 1950. (auth)

Results are summarized for a survey of methods for predicting fuel element and coolant behavior in sodiumcooled fast reactors under abnormal operating conditions. Circumstances prior to, during, and after meltdown are considered, and the behavior of fuel and coolant during transients is discussed. Reactor excursions, theory of fuel element thermal transients, reactor coolant transients in single and two-phase flows, and specific topics such as two-phase flow patterns, two-phase pressure drop, and transient voids in boiling coolant reactors are also treated. Some applicable mathematical treatments are given along with an annotated bibliography. (D.L.C.)

A dissolver design was demonstrated on a laboratory scale for the electrolytic dissolution of nuclear fuels. Simplified electrodes are used which need not touch the fuel pieces, thus avoiding the usual problems of achieving adequate electrical contact between the fuel and the anode basket. Because a series of electrolytic cells are formed along the length of the dissolver, current efficiency is enormously increased; this technique allows for the use of higher voltage and much lower current than is presently considered essential in plant-scale electrolytic dissolution. (auth)

ICPP Operations. Changes made in processing equipment are described, and the use of continuous steam stripping to free waste solvent of Pu is described. Agueous Processing Studies. Studies were made of methods for separating Zr from dissolver solutions of U-Zr alloys. Recovery of U from BeO/ sub 2/-UO/sub 2/ ceramic fuels by grinding-leaching technique using boiling HNO/ sub 3/ reached 75 to 80%. Waste Calcination. Test results of feed spray nozzles for use in the Demonstrational Waste Calcining Facility are given. Studies were made on the calcination of aluminum nitrate and zirconium fluoride waste solutions. Waste Treatment. Removal of Cs and Sr from wastes by adsorption was investigated. The conditions for optimum separation of Fe, Ni, and Cr by Hg cathode electrolysis from waste solutions resulting from processing of stainless steel reactor fuels were determined. Electrolytic Dissolution Systems. The electrolytic dissolution of type 304 stainless steel was studied in the transpassive region as a function of electrode potential and HNO/sub 3/ concentration. An analog simulation study of an electrolytic dissolver is described. A niobium cathode in an electrolytic dissolver dissolving stainless steel in boiling HNO/sub 3/ did not absorb H/sub 2/. The corrosion resistance of several container materials to 1 …

High-purity uranium monocarbide reacted with water at 80 deg C to produce a finely divided, brown U(IV) compound, and 92 nfl (STP) of gas per gram consisting of 11 vol% hydrogen, 86 vol% methane, 2 vol% ethame, and 0.6 vol% propane. At 90 deg C, the products were the same, but the reaction rate was higher. Reaction with 5.6 M HCl was slower than with water, but the gaseous products were essentially the same. In preliminary experiments at 80 deg C with UC-UC/sub 2/ mixtures containing less than 2 wt.% free carbon, the volume of gas evolved per gram of sample hydrolyzed decreased from 92 to 32 ml (STP) and the methane concentration from 86 to 14 vol% as the UC/sub 2/ concentration in the mixture increased from 0 to about 63 wt.%. An attendant increase in the hydrogen and ethane concentrations to 23 and 38 vol%, respectively, also occurred. (anth)

Machining was completed on the s-tube flow element, and a spring, for use at a constant known temperature, was constructed for the flow element. Calculations for geometry factor, detector efficiency, and effective absorption along the useful radiation path were completed for the reed densitometer. The flow rate control was calibrated and performed satisfactorily. Response to step transient changes occurred with a damping constant of about 0.6 and an effective response time of 10 sec. Sources of error in the s-tube flow rate measurements are discussed. (M.C.G.)

This report details activities of the Fuels Development Operation for the months of April, May, and June 1961.

The original charge for the E-N core load at H reactor, consisting of five different types of charges, each group of five containing 199 .947 per cent enriched uranium E-pieces of six inch nominal length and 16 Li-Al I&E (N) pieces of four inch nominal length plus mixers, was intended to provide enough excess reactivity to operate the reactor at all times with reasonable but not excessive flexibility. During actual operation the excess reactivity observed has been somewhat greater than conservatively planned. In addition, a very slight long-term gain rather than the expected loss has been observed up to this time (73 MWD/column average exposure). On this basis, a modification of the original charge makeup has been determined which will permit increased conversion and operating efficiency.

The mechanisms and kinetics of the loss of boron during heating at 1135 deg C under various dynamic environments were determined from powder compacts of 5 wt% elemental boron dispersed in matrices of Fe, Cr, Ni, Si, Fe/sub 2/O/sub 3/, Cr/sub 2/O/sub 3/, NiO, and SiO/sub 2/, compacts of austenitic stainless steel alloy powder containing 0.25 wt% boron, and wrought specimens of 0.13 wt% boron-- stainless steel alloy. The compacts containing 5 wt% boron were heat treated in vacuum, highpurity argon, wet helium, and hydrogen. With the exception of those heat treated in hydrogen, significant boron losses occurred only when a supply of oxygen, either from the sample itself or as a deliberate addition to the heat- treating environment, was available. Correspondingly, the loss mechanism is postulated to be the oxidation of boron to boron sesquioxide and its volatilization from the sample. The loss rate is controlled by the volatilization rate of the oxide which is directly influenced by structure of the compact and sintering environment. Independent of the chemical nature of the matrix, boron losses were incurred during heat treatment in hydrogen. Variations of the water content of the hydrogen from 7 to 460 ppm did not significantly influence …

Changes in neutron multiplication caused by voids in the island of the HFlR were calculated and measured experimentally. The results indicated that with only water initially in the island the maximum change in neutron multiplication ( DELTA k/sub max) associated with island voids is 0.032 with a corresponding void fraction of 70%. With a simulated 300 g Pu target in the island DELTA k/sub max/ was 0.0l6, and the corresponding void fraction was 42%. In view of these large changes in neutron multiplication, calculations were made to determine what additional materials could be used in the island to reduce DELTA k/sub max/ and what the associated decrease in peak thermal flux wouId be. The results indicated that of the materials considered the use of beryllium in the water island resulted in the smallest decrease in flux for a specified DELTA k/sub max/. To reduce DELTA k/sub max/ to 0.01 required 26% by volume of beryllium in the island; the corresponding reduction in thermal flux, as compared to an all-water island, was about 10%. In order to reduce DELTA k/sub max/ to 0.0l with a 300 g Pu target in the island, the aIuminum-to-water ratio of the target had to be …

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The means used to prevent the recurrence of tetralin leakage into the SRE sodium systems are discussed. Included is a description of the redssign of system components to utilize alteraate coolants such as nitrogen, air, and NaK. The use of kerosene to replace tetralin, where double containment is provided, is discussed. The physical properties are compared, and kerosene is shown to be free of the undesirable characteristics of tetralin. The fuelelement cleaning systsm was redesigned for steam washing, followed by a water rinse and vacuum drying. Hydrogen gas evolved during washing is oxidized with copper oxide to eliminate the possibility of a hydrogen-oxygen explosion if air should accidentally enter the vent system. The fuel element was changed from a seven- to a five-rod cluster to provide additional clearance in the channel. Element hardware was modified to provide an orifice location which will permit more precise flow calculations; a redesigned hanger assembly which will minimize sodium holdup; and filter screene at the channel entrance to prevent in-cluster plugging. Diagnostic instrumentation was provided for the reactor to monitor: fission-product activity in the reactor cover gas; rapidly varying reactor parameters during a reactor scram; internnl and aheath fuel temperatures; and fuinctions being performed …

Uranium-aluminum compounds were prepared by solidsolid reaction of aluminum powder and uranium hydride; x-ray-diffraction patterns showed that single phases of UAl/sub 2/, UAl/sub 3/, and UAl/sub 4/ could be achieved. The uranium-beryllium compound, UBe/sub 1//sub 3/, was prepared by solid-solid reaction of berylllum powder and uranium hydride. The uranium-boron compounds, UB/sub 2/ UB/sub 4/, and UB/sub 1//sub 2/ were prepared by solid reaction, and single borides were obtained; carbon contamination was especially serious in these samples. The uranium-carbon compounds, UC and UC/sub 2/, were prepared by solid-solid reactlons to 1200 deg C; the x-ray-diffraction patterns showed a mixture of phases, and higher temperatures are probably required. The uranium- nitrogen compounds, UN and UN/sub 2/, were prepared by reaction of uranium with ammonia at 850 deg C for UN/sub 2/ and subsequent heating of that product in vacuum for UN. The uranium-selenium compounds, USe and USe/sub 2/, were prepared in very small samples; the violence of the reaction of selenium with uranium hydride and the lack of availability of hydrogen selenide limits the size of preparations. The uranium-silicon samples, USi/sub 2/ and USi/sub 3/ were prepared by solid-solid reaction of UH/sub 3/ and 8i; numerous attempts were made to prepare U8i. …

Short-term corrosion tests with types 1100, 5154, 6061, and X8001 aluminum alloys were conducted in water at flow rates rsnging between 20 and 107 fps and at temperatures between 170 and 290 deg C. Corrosion of the alloys was less dependent on flow rate in the range of 20 to 67 fps than at higher velocities. At temperatures as high as 230 deg C no evidence of localized attack, except for random shallow pitting, was exhibited by these alloys, and all had comparable corrosion rates. At 260 and 290 deg C all alloys except X8001 showed extensive subsurface attack. At 260 deg C and at velocities up to 67 fps, the corrosion rate of X8001 aluminum was high during the early part of a run and then decreased to rates of between 5 and 15 mpy; at the highest velocity, the corrosion rate was constant at 200 mpy. Tests with X8001 aluminum at 260 deg C showed that mechanically polished specimens corroded at about the same rate as those with a machine finish. A significsnt improvement in corrosion resistsnce at 20 to 67 fps was accomplished, however, by exposing the specimens to water at 250 or 300 deg C in …

Work done on the EGCR graphite combustion problem that may follow from the maximum credible accident, that is the rapid loss of pressure from the primaryreactor coolant system is summarized. The solution to date is to protect the fuel support sleeves with a siliconized siliconcarbide coating and to allow the moderator surfaces to oxidize. The moderator surfaces have available only 6.5% of the total core flow which places an upper limit on the rate of oxidation. The rate of heat removal through the sleeve to the main coolant flow is sufficient to cause a decrease in temperature throughout the reactor and subsequent quenching of the oxidation. This method depends only on continued coolant flow from one blower. Problems attendant with this and other schemes of controlling the fire are discussed. (auth)

WHIRLAWAY is an IBM 7090 FORTRAN programmed code for the solution of two- group neutron diffusion equations in xyz geometry. The code was designed to run under control of the IBM 7090 FORTRAN Monitor System on a machine with at least six tape units. The maximum number of mesh points is limited to 12,750. Arbitrary distributions of materials and mesh spacing are permitted. The boundary conditions are either zero flux or zero current at each of the six faces of the reactor, and the code will, if desired, compute the adjoint-flux and associated flux-adjoint-flux region integrals that are necessary for perturbation calculations. Computation time is approximately 0.006 sec per point iteration. Normally, running times are about 2 to 3 hr for a 10,000-point problem. (auth)

A study was conducted to assess the feasibility of transporting the first spent core of the Elk River Power Reactor to Policoro, ltaly. Commercial transport arrangements were also examined and it was found that changes in indemnity and/or insurance are required. Other aspects appear favorable. (J.R.D.)

A new model of the higher symmetry of elementary particles is introduced ln which the eight known baryons are treated as a supermultiplet, degenerate in the limit of unitary symmetry but split into isotopic spin multiplets by a symmetry-breaking term. The symmetry violation is sscribed phenomenologically to the mass differences. The baryons correspond to an eight-dimensional irreducible representation of the unitary group. The pion and K meson fit into a similar set of eight particles along with a predicted pseudoscalar meson X/sup o/ having I = 0. A ninth vector meson coupled to the baryon current can be accomodated natarally in the scheme. It is predicted that the eight baryons should all have the same spin and parity and that pseudoscalar and vector mesons should form octets with possible additional singlets. The mathematics of the unitary group is described by considering three fictitious leptons, nu , e/sup -/ , and mu /sup -/, which may throw light on the structure of weak interactions. (D. L.C.)

Studies carried out on corrosion associated with the hydrofluorination- dissolution phase in the fused-salt Fluoride Volatility Process are summarized. Corrosion for hydrofluorination-dissolver vessels used in bench-scale and semiworks-scale process development at ORNL is discussed. The results of a study on construction materials for the dissolution phase are presented. Corrosion studies at ANL are described for comparison purposes. A full-size hydrofluorinator dissolver is described. (M.C.G.)