From International Conference on Nuclear Physics with Reactor Neutrons, Argonne, Ill., Oct. 1963. Experiments were performed in which the kinetic energies of correlated fragment pairs from thermal- and resonance-neutron-induced fission were measured. In addition, a three-parameter ternary fission experiment was performed in which the energies of correlated fragments were measured in coincidence with the energy of a third emitted particle, usually a long-range alpha particle. The detectors were large-area silicon surface barrier detectors. The instrumentation associated with these experiments is discussed in detail. The complete system is described, with attention given to the problems of background reduction (fast-coincidence requirements), stability, linearity, and resolution. Particular attention is given to the reduction of spectrum distortion by pile-up pulses (alphaon-fission pile-up within the amplifier resolving time). Methods and limitations of pile-up detection are discussed. A new method for inspection and removal of pile-up pulses is described. (auth)

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From American Nuclear Society Meeting, New York, Nov. 1963. The use of the asymptotic solution to the one-velocity transport equation is considered. The angular distribution for fast neutron elastic scattering by heavy elements is discussed. An exponential angular distributi on is assumed to simplify the decay length calculation. The diffusion length of 1 to 15 Mev neutrons in iron is calculated, as well as the vector flux angular dependence. The asymptotic solution for an arbitrary angular distribution of a plane delta -function source is also found. An isotropic source is investigated, and some applications of the model are examined. (auth)

An investigation was conducted on the impossible use of beta radiation to promote chemical reactions at high temperatures and pressures. The advantages of beta sources over other radiation sources are enumerated. A radiation processing apparatus is described which allows operations to 10,000 psi and 500 deg C and uses 90 C of Sr/sup 90/-Y/sup 90/. The dosimetry of the source was accomplished with an iodineheptane system, and the mean dose rate within the chemical reactor was determined to be 0.98 x 10/sup 6/ rad/hr. The radiation utilization efficiency in the dosimetry measurements was determined to be 34.7%. Results of runs on hydrogenation of coal extract indicate that radiation does not increase the extent of hydrogenation, but that radiation reduces the content of hetero atoms N and S in the 100 x 400 deg C boiling oil products. The use of beta radiation in the hydrorefining of oils is suggested. (D.L.C.)

The program KRUDE, which solves the slowing down and adjoint equations for a mixture of resonance and nonresonance isotopes in an infinite homogeneous medium, was used to evaluate some resonance capture approximations (variational and successive) that use linear combinations of narrow and wide resonance fluxes. Results obtained for resonance capture in the 291-ev resonance of Zr/sup 91/ and the 192-ev resonance of U/sup 238/ are compared, and three methods for including Doppler effects in the variational method are considered. (D.C.W.)

A review is presented on vapor-liquid equilibria. Arnong the topics discussed are activity coefficients, consistency criteria, automatic computation, and gaseous mixtures. A bibliography of 18 references is included. (D.L.C.)

Fuel blocks of compacted ZrO/sub 2/ and UO/sub 2/ powder in paraffin were added axially to two unreflected assemblies (20 x 16 in. and 20 x 24 in. cross sections). The separation of the assembly halves when criticality occurred was determined, and the reactivity worth at a given critical gap size was obtained by bringing the halves slightly closer together and observing the reactor period. The core with the larger cross section had a maximum gap twice that of the smaller core. Diffusion theory treatment agreed with the data reasonably well for small gap thickness. (D.C.W.)

From American Nuclear Society Meeting, New York, Nov. 1963. The need for control of the flow distribution and/or steam quality in boiling reactors is discussed. A quality control device is being developed which consists of an entrance venturi and an exit venturi for measuring the flow rates into and out of the channel, means for comparing the two flow rate signals, and a value for regulating the flow rate. This device can be used either as a constantquality device or as a controlled-quality device. Results are given of air-water studies of two-phase flow in a vertical venturi. (D.L.C.)

An isochronal differential-type microcalorimeter has been designed and constructed. As a result of its simple design it is very easy to handle the samples and assemble the calorimeter. Important to the operation of the calorimeter is a program, also working on the differential principle, that provides linear temperature rise of the samples. The calorimeter is used to measure very small energy releases such as those found in precipithtion, stored energy, etc. It is demonstrated that the calorimeter is easily capable of measuring 0.005 cal with a probable error of the order of 1 to 2%. (auth)

The performance of large pressurized-water reactors operated with a uniformly distributed control technique such as a soluble neutron poison (boric acid) dissolved in the moderator is investigated. The cycling studies are performed in one dimension. (C.E.S.)

The isotope Re/sup 189/ was produced by fsst neutron irradiation of osmium and by the ( alpha ,p) reaction on tungsten. The rhenium was separated chemically from the target material, and beta, gamma, and internal conversion spectra were measured. The mass assignment is confirmed by the observation of eleven electromagnetic transitions in the Os/sup 189/ daughter, including the 30.8-kev isomeric transition (8 hr), all of which were known from the decay of Ir/ sup 189/. Re/sup 189/ has a half-life of 23.4 plus or minus 1.0 hr and emits betaray groups with end-point energies 1000, 780, and 725 kev, and probably others. Results of coincidence measurements lead to some new information about the level scheme of Os/sup 189/ Evidence was found for strong rotation-particle coupling between low-lying K =1/2 and K = 3/2 bands in Os/sup 189/. 40 references. (auth)

Data are reviewed from a number of studies on the metabolism of Mg in man and the role of Mg in biological processes. Results are reported from studies using Mg/sup 28/ as a tracer of Mg metabolism in laboratory animals and in man in health and various disease states. It is postulated that the role of Mg in many vital processes may be explained by the fact that the Mg ion tends to form hydrates and double salts and hence has the capacity for complex formation. (C.H.)

New experimental data and literature data are utilized to determine the upper temperature of usefulness of zirconium alloys. Three basic engineering assumptions are used: (1) service life requirements are on the order of four years; (2) tubular fuel cladding for rod-type fuel is considered with a maximum wall thickness of 1.27 cm; and (3) heat fluxes are above 157 watts/cm/sup 2/. The interrelation of three basic factors, corrosion rate, corrosion embrittiement by hydrogen and oxygen, and strength are considered. An upper limit for an acceptable corrosion rate for a long-term service of 1 mg/dm/sup 2//day is set primarily by the effect of heat-transfer on corrosion. For the best alloys anticipated, this requirement (even without considering transient conditions) limits cladding surface temperatures to less than 540 C. Oxygen embrittiement of the alloy substrate by oxide film dissolution is not expected to be a limiting factor. Corrosion hydrogen embrittiement was studied in detail and found to limit acceptable service to cladding surface temperatures of less than 525 deg C for established experimental alloys. Hydrogen embrittlement may not be a limiting factor if alloys corrosion resistant enough to be acceptable above 600 deg C could be developed. Zirconium alloys designed for higher strength …

l963. The Wisconsin tandem accelerator is used part of the time for experiments in neutron physics. In these experiments the properties of neutrons from charged-particle reactions as well as the interaction of neutrons with nuclei are studied. Some of the techniques used and some of the results obtained are described. (auth)

The effects of competition between resonances of different isotopes were investigated. Flux and reaction rate calculations on a Pu/sup 239/-- U/sup 238/ system revealed that U/sup 238/ exhibits both self-shielding and interference effects, the latter becoming noticeable at enrichnnents of a few per cent. Gold activation was also found to be depressed by the presence of U, but was insensitive at low enrichment values, Investigation of the Pu/sup 239/ resonance integral showed an asymmetric effect involving both interference between potential and resonant scattering and interferance with resonance absorption in another isotope. The interference scattering arising in each resonance level had a notable effect on the average change in the Doppler coefficient. (D.C.W.)

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Methods for determining the heavy element isotopic compositions and atom percent fission for reactor fuels are briefly described, and their accuracies are discussed. (D.C.W.)

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The successes and difficulties of the Bloch model of a metal are briefly reviewed, and the Landau quasi-particle theory amd the pseudopotential theory are briefly discussed. These two notions are made the basis for a revised version of the Bloch model that avoids the conceptual difficulties of the original model, while retaining and explaining its appealing features. Well known empirical generalizations concerning the relative importance of conduction-electron density, composition, and structure for the electronic properties are presented, and their implications are reexamined. A theory of the form required by the empirical generalizations is developed. Recent approximate calculations are discussed, and a variety of conclusions are drawn from these relating to the possibility of explanation of the empirical generalizations by the theory. 42 references. (auth)

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One-region buckling measurements that were made on a series of D/sub 2/O- moderated lattices of heavy uranium metal tubes in the Process Development Pile at Savannah River Laboratory are presented. The purposes of these measurements are to provide normalization points for lattice bucklings and to extend the study of natural uranium- D/sub 2/O systems. The dependence of buckiing on the moderatorto-fuel ratio is studied for two types of lattices. (R.E.U.)

The diffraction techniques used at ANL to obtain scattering amplitudes and cross sections for elements and isotopes are briefly described; and some results obtained for Zr, Tc/sup 89/, Os, Os/sup 188/, Os/sup 189/, Os/sup 190/, Os/sup 192/, K, K /sup 39/, Rb, Rb/sup 85/, Ir, and Mg are summarized. (D.C.W.)

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A survey is presented of three processes of water movement which will result in movement of chemicals: miscible displacement, diffusion, and leaching. Miscible displacement is discussed in some detail. Movement of pesticides in soils is considered. (D.L.C.)