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Neptunium distribution coefficients from acid nitrate, chloride, and sulfate solutions by several organic nitiogen and phosphorus compounds were measured as functions of several extraction variables, including neptunium valence, acid and salt concentration, and reagent concentration. Extractability by all the reagents varied in the order Np(IV)> Np(VI)>> Np(V). Except for primary amines, all reagents extracted Np(IV) much more strongly from nitrate than sulfate solutions. Among organonitrogen compounds the order of extractability of Np(IV) was: quaternary> tertiary> primary and secondary from nitrate solutions but primary>> secondary> tertiary from sulfate solutions. Neptunium(IV) nitrate extractions with the different extractants passed through maxima at widely different acid concentrations. In most cases, extraction increased when nitric acid was replaced by nitrate salt. Extraction was usually approximately proportional to the square of the reagent concentration. (auth)

In the present ISABELLE design, the luminosity at each insertion will be the same, unless special efforts are taken to get a low-..beta.. insertion or reduced crossing angle. These can only change the luminosity by factors of 2 to 4 from insertion to insertion. An estimation of the range of desired luminosities is given.

Thermoluminescence in potassium dihydrogen phosphate (KDP) induced by Co/ sup 60/ gamma irradiation at liquid nitrogen temperature (-198 deg C) was investigated. Glow curves in the temperature range --196 to 0 deg C were measured for a series of gamma exposure dosages ranging from 10/sup 4/ roentgen to 5 x 10/sup 6/ roentgen. The heating rate used for glow curve measurements was 12 deg C per minute. Twice recrystallized Mallinckrodt reagent grade potassium dihydrogen phosphate, with a grain size between 100 and 170 mesh, was used for most samples. In the case of the powder samples, the glow curve for an exposure dose of 10/sup 4/ roentgen exhibited two peaks in this temperature range, one at approximately --78 deg C and the other at approximately -146 deg C. The -78 deg C peak split into two distinct peaks with increasing dosage. At still higher doses an additional peak at about -9 deg C became evident. This peak may, however, be due to aluminum oxide. Calculation of the trap depth, E, and the frequency factor, s, associated with the --78 deg C peak, by the approximate method of Grossweiner yielded values of 0.485 ev and 9.97 x 10/sup 10/ sec/sup -1/ …

The soil microflora and its respiratory activity were measured in soil cores collected at different distances from an unshielded reactor. No direct correlation was found between dose received and microbial counts or respiration. Indication of a correlation between dose and microbial respiration was obtained after eliminating the overriding influence of moisture. Radiation probably affected the soil microflora through damage to the phanerogam vegetation rather than directly. This preliminary study indicates the need to have undisturbed sampling areas close to the ORNL fast burst reactor. Extensive dosimetry, both in and above the soil, in these areas, and a program of long-term ecological descriptibn, should be started before the reactor becomes operational. (auth)

Thirty-nine one meter square proportional chambers with delay line readout were constructed for the external muon identifier of the Fermilab 15 foot bubble chamber. They provide X,Y,U(45/sup 0/) and T (avalanche time) information using a single wire plane, etched strip cathodes and nine amplifiers. They have a time resolution of +-27ns, single particle spatial resolution of +-2 to +-3mm and double particle resolution of approximately 2/sup 1///sub 2/ to 4cm. The energy accessible to each wire is limited so none of the wires in the first 25 chambers has broken since their installation in 1973 to 1974.

for filtration of plutonium oxalate slurries. A scalpel produces a slit in the filter precoat, leading to increased filtration in this slit, and the oxalate is removed by a doctor knife; this technique results in prolonged blowback cycles and more uniform delivery of filtered oxalate to subsequent processing steps. Several types of filter media were tested, and rigid porous aluminum oxide was found to be the best one. (D.L.C.)

The use of electron impact broadened resonance lines to diagnose near-term high density diagnostics is discussed. In particular, the question of how to choose seed and pusher materials to have discernible broadening effects while maintaining line visibility is discussed.

A target system for the production of /sup 18/F by proton bombardment of H/sub 2//sup 18/O was designed for the ORNL 86-inch cyclotron facility. The system consists of concentric titanium and aluminum cylinders. Oxygen-18-enriched H/sub 2/O circulates through the inner titanium cylinder and through an external heat exchanger with cooling water flowing in the annulus. Yields of 5.0 curies are expected for a 250-..mu..A proton beam current and 24-min irradiation time.

The development of several metallic fuei element systems for air-cooled reactors is reviewed, and the hightemperature properties of Type 310 stainless steel and Nichrome V clad fuel elements are discussed. Early work on cladding of Mo is reviewed, and recent developments in ferrous-base alloys and Cr-base alloys as hightemperature cladding materials are presented. (auth)

The heat exchanger of the calciner consists of a vessel into which unfired, horizontal, bayonet tubes extend in a fluidized bed. Strain measurements were taken on several of the tubes under simulated operating conditions and the associated dynamic stresses were calculated. Vibrations greater than design limitations for indefinite operation were found to exist. To restrict these vibrations and prevent further tube fatigue cracking, a tube support was installed. Since the installation of the support, the calciner has operated satisfactorily over 1275 hours. (auth)

The EOCR prototype control rod, control rod drive, and driver fuel assembly were extensively tested in 500 deg F Santowax and 132 deg F water. These tests not only established the operating characteristics of these assemblies but also revealed a number of deficiencies in the various components. The modifications required were tested to establish the satisfactory performance of the modified components. Flow versus pressure differential measurements were performed on the driver fuel and the control rod. These measuremerts were also performed on various sized orifices in both assemblies to facilitate final orifice sizing when the final physics and heat transfer calculations have been completed. Scram insertion time curves were obtained for a variety of control rod configurations and test conditions. These curves not only established the scram insertion reliability of the control rod but also provided the basis for performing a control rod force analysis. Included are descriptions of the control rod, control rod drive, and driver fuel assembly together with descriptions of their method of operation. (auth)

Pressure-volume, uniaxial stress loading to failure, uniaxial strain, and acoustic velocity determinations were made on Blair dolomite at confining pressures ranging to 3.5 GPa (Pa = Paschals where 10/sup 5/ Pa = 1 bar or 0.1 GPa = 1 kbar). The bulk modulus K, rapidly rises from an initial 10.4 GPa (at atmospheric pressure) to 102.0 GPa at 1 GPa pressure. At higher pressures, K remains essentially constant (110 GPa). The maximum volume change on loading is 3.9% at 3.5 GPa; the unloading closely follows the loading path. Comparison of uninxial stress tests in compression to 0.7 GPa and extension to 2.1 GPa confining pressure demonstrates that the characteristic shear stress at failure as well as the transition from brittle fracture to ductile flow is strongly dependent upon both the value of the intermediate principal stress sigma /sub 2/ and the rate of strain. The onset of dilatancy as determined in uniaxial compression occurs at about two-thirds of the failure stress. The uniaxial strain loading path is well below the failure envelope in compression. In uniaxial stress loading (compression), Young' s modulus (E) and shear modulus ( mu ) are demonstrated to be very sensitive to both confining pressure and …

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It was demonstrated that a transient surface-current pulse can be sensed and recorded by a graded-Hc film, a magnetic film with the coercive force Hc varying along the length of the film. Information on the magnitude of the current can be obtained by comparing the domain-wall location with the distribution of Hc value along the film. The transient characteristic of the current pulse can be deduced from the V-shaped configuration of the domain wall. (auth)

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Molecular beam epitaxy was used to deposit body centered cubic single crystal Fe{sub 1-x}Ga{sub x} thin films on MgO(001) and ZnSe/GaAs(001) substrates well beyond the bulk stability concentration of about 28%. The crystal quality of the substrate surface and each deposited layer was monitored in situ by reflection high energy electron diffraction. The magnetization of the samples as a function of Ga is found to decrease more rapidly than a simple dilution effect, and element-specific x-ray magnetic circular dichroism ascribes this trend to a decrease in the Fe moment and an induced moment in the Ga that is antialigned to the Fe moment.

This paper describes how a passive quench protection system can be applied to long superconducting solenoid magnets. When a solenoid coil is long compared to its thickness, the magnet quench process will be dominated by the time needed for uench propagation along the magnet length. Quench-back will permit a long magnet to quench more rapidly in a passive way. Quenchback from a conductive (low resistivity) mandrel is essential for spreading the quench along the length of a magnet. The andrel must be inductively coupled to the magnet circuit that is being quenched. Current induced in the mandrel by di/dt in the magnet produces heat in the mandrel, which in turn causes the superconducting coil wound on the mandrel to quench. Sub-divisions often employed to reduce the voltages to ground within the coil. This paper explores when it is possible for quench-back to be employed for passive quench protection. The role of sub-division of the coil is discussed for long magnets.