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Innovations in Los Alamos alpha box design (open access)

Innovations in Los Alamos alpha box design

Destructive examinations of irradiated fuel pins containing plutonium fuel must be performed in shielded hot cells with strict provisions for containing the plutonium. Alpha boxes provide containment for the plutonium, toxic fission products, and other hazardous highly radioactive materials. The alpha box contains windows for viewing and a variety of transfer systems specially designed to allow transfers in and out of the alpha box without spread of the hazardous materials that are contained in the box. Alpha boxes have been in use in the Wing 9 hot cells at Los Alamos National Laboratory for more than 20 years. Features of the newly designed alpha boxes are presented.
Date: January 1, 1985
Creator: Ledbetter, J. M.; Dowler, K. E. & Cook, J. H.
System: The UNT Digital Library
Scheme to funnel ion beams with a radio-frequency quadrupole (open access)

Scheme to funnel ion beams with a radio-frequency quadrupole

We describe a proposed method to funnel ion beams using a new form of the radio-frequency quadrupole (RFQ) structure. This RFQ accepts two bunched ion beams and combines them into a single final beam with interlaced microstructure pulses. It also provides uninterrupted periodic transverse focusing to facilitate the funneling of beams with high current and low emittance.
Date: January 1, 1985
Creator: Stokes, R.H. & Minerbo, G.N.
System: The UNT Digital Library
Gamma-spectrometry with Compton suppressed detectors arrays (open access)

Gamma-spectrometry with Compton suppressed detectors arrays

Recent results of experiments performed with two different Compton-suppressed detectors arrays in Daresbury and Berkeley (/sup 163,164/Yb and /sup 154/Er, respectively), are presented together with a brief description of the national French array presently under construction in Strasbourg. 25 refs., 15 figs.
Date: January 1, 1985
Creator: Schueck, C.; Hannachi, F.; Chapman, R.; Lisle, J. C.; Mo, J. N.; Paul, E. et al.
System: The UNT Digital Library
Spin dynamics on percolating networks (open access)

Spin dynamics on percolating networks

We have used inelastic neutron scattering to measure the order parameter relaxation rate GAMMA in the dilute, two-dimensional Ising antiferromagnet Rb/sub 2/CoMg/sub 1-c/F/sub 4/ with c very close to the magnetic percolation threshold. Where kappa is the inverse magnetic correlation length, GAMMA approx. kappa/sup z/ with z = 2.4/sub -0.1//sup +0.2/. Our results are discussed in terms of current ideas about spin relaxation on fractals. 13 refs., 1 fig.
Date: January 1, 1985
Creator: Aeppli, G.; Guggenheim, H. & Uemura, Y.J.
System: The UNT Digital Library
Accurate determination of the parameters of the 292. 4-eV resonance of /sup 91/Zr and the 301. 1-eV resonance of /sup 96/Zr (open access)

Accurate determination of the parameters of the 292. 4-eV resonance of /sup 91/Zr and the 301. 1-eV resonance of /sup 96/Zr

High-resolution transmission measurements of zirconium metal samples have been carried out at ORELA using the 80-m flight path and an improved /sup 6/Li-glass scintillation neutron detector. Four different thicknesses of the pure zirconium metal and one sample of zircaloy were used in four separate experiments. The transmission data for these samples were measured at room temperature, and one sample was cooled to liquid nitrogen temperature. These data were analyzed using the multilevel R-matrix computer code SAMMY. The resonance parameters obtained for the 292.4-eV resonance of /sup 91/Zr (including both statistical and systematic uncertainties) are: J/sup ..pi../=3/sup +/, E/sub 0/=292.40 +- 0.10 eV, GAMMA/sub n/=665 +- 5 MeV, GAMMA/sub ..gamma../=131 +- 10 MeV, and cc(GAMMA/sub n/, GAMMA/sub ..gamma../)=0.14. The parameters obtained for the 301.1-eV resonance in /sup 96/Zr are: J=1/2, E/sub 0/=301.14 +- 0.10 eV, GAMMA/sub n/=223 +- 7 meV, GAMMA/sub ..gamma../=285 +- 38 MeV, and cc(GAMMA/sub n/, GAMMA/sub ..gamma../)=0.80.
Date: January 1, 1985
Creator: Salah, M.M.; Harvey, J.A.; Hill, N.W.; Hussein, A.Z. & Perey, F.G.
System: The UNT Digital Library
Comparison of phosgene, chlorine, and hydrogen chloride as reagents for converting molten CaO. CaCl/sub 2/ to CaCl/sub 2/ (open access)

Comparison of phosgene, chlorine, and hydrogen chloride as reagents for converting molten CaO. CaCl/sub 2/ to CaCl/sub 2/

One method at Los Alamos for preparing impure plutonium metal from the impure oxide is by batch reduction with calcium metal at 850/sup 0/C in a CaCl/sub 2/ solvent. The solvent salt from this reduction is currently discarded as low-level radioactivity waste only because it is saturated with the CaO byproduct. We have demonstrated a pyrochemical technique for converting the CaO to CaCl/sub 2/ thereby incorporating solvent recycling into the batch reduction process. We will discuss the effectiveness of HCl, Cl/sub 2/, and COCl/sub 2/ as chlorinating agents and recycling actual spent process solvent salts. 6 refs., 8 figs.
Date: January 1, 1985
Creator: Fife, K. W.
System: The UNT Digital Library
Formation of microvilli (open access)

Formation of microvilli

Microvilli on cells frequently display a regular hexagonal packing pattern. We present here a model for how this regular pattern is established and how the microvilli are extruded from the cell. The model is based on the viscoelastic properties of the actomyosin gel in the cell cortex. 16 refs., 7 figs.
Date: January 1, 1985
Creator: Oster, G. F.; Murray, J. D. & Odell, G. M.
System: The UNT Digital Library
Evolution of nuclear shapes at high spins (open access)

Evolution of nuclear shapes at high spins

The dynamic electric quadrupole (E2) moments are a direct reflection of the collective aspects of the nuclear wave functions. For this, Doppler-shift lifetime measurements have been done utilizing primarily the recoil-distance technique. The nuclei with neutron number N approx. 90 possess many interesting properties. These nuclei have very shallow minima in their potential energy surfaces, and thus, are very susceptible to deformation driving influences. It is the evolution of nuclear shapes as a function of spin or rotational frequency for these nuclei that has commanded much interest in the lifetime measurements discussed here. There is growing evidence that many deformed nuclei which have prolate shapes in their ground states conform to triaxial or oblate shapes at higher spins. Since the E2 matrix elements along the yrast line are sensitive indicators of deformation changes, measurements of lifetimes of these states to provide the matrix elements has become the major avenue for tracing the evolving shape of a nucleus at high spin. Of the several nuclei we have studied with N approx. 90, those to be discussed here are /sup 160,161/Yb and /sup 158/Er. In addition, the preliminary, but interesting and surprising results from our recent investigation of the N = 98 …
Date: January 1, 1985
Creator: Johnson, N.R.
System: The UNT Digital Library
Logical and physical database design within a full-text environment (open access)

Logical and physical database design within a full-text environment

This paper describes the problems and solutions encountered in the design of logical and physical data bases within a full-text environment. A full-text environment can be defined as data bases that store both citation information as well as actual document text. The problems/solutions encountered were a result of the necessity to integrate distinct physical data bases into a single logical data base without the assistance of a Data Base Management System that is capable of physical data base integration.
Date: January 1, 1985
Creator: Michelsen, C.D. & Shafer, D.F.
System: The UNT Digital Library
Verification of steady-state temperature predictions in an instrumented LMFBR driver subassembly (open access)

Verification of steady-state temperature predictions in an instrumented LMFBR driver subassembly

Purpose of this paper is to compare the predicted steady-state coolant temperatures obtained by a thermal-hydraulic computer code with the measured coolant temperatures obtained from the instrumented LMFBR subassembly XX09 during reactor run 129C while the Experimental Breeder Reactor II (EBR-II) was essentially at full power and flow conditions.
Date: January 1, 1985
Creator: Betten, P.R.; Feldman, E.E.; Chang, L.K.; Mohr, D. & Planchon, H.P.
System: The UNT Digital Library
Absolute Wavelength Measurement and Fine Structure Determination in /Sup 7/Li Ii (open access)

Absolute Wavelength Measurement and Fine Structure Determination in /Sup 7/Li Ii

The energy levels of two-electron atoms continue to provide rigorous tests of relativistic quantum theory, and of correlation effects within a multi-particle system. These interactions are determined perturbatively, with several approximations, and theoretical results often differ. It is critical to provide precise measurements of absolute wavelengths connecting these atomic energy levels to obtain a resolution of the precision of the different parts of such complex calculations. In this work, we report a high precision optical measurements in the 1s2s /sup 3/S - 1s2p /sup 3/P multiplet of Li II using fast-beam laser spectroscopy. A collinear interaction using both parallel and antiparallel laser and ion beams allows both for precise elimination of large Doppler shifts, and for a strong kinematic narrowing of the observed resonances, as compared with thermal beam experiments. The wavelengths of the observed resonance fluorescence radiation are determined by comparing them with simultaneously recorded saturated absorption profiles of molecular iodine hyperfine components. In turn, the absolute wavelengths of the iodine lines are obtained from precisely calibrated Fabry-Perot etalon fringes in a separate experiment. The final precision of the Li II wavelengths is 5 parts in 10/sup 9/, which is at a level of precision of 80 ppM of …
Date: January 1, 1985
Creator: Riis, E.; Berry, H.G.; Poulsen, O.; Lee, S.A. & Tang, S.Y.
System: The UNT Digital Library
Can antibaryons signal the formation of a quark-gluon plasma (open access)

Can antibaryons signal the formation of a quark-gluon plasma

We report on recent work which indicates that an enhancement of antibaryons produced in the hadronization phase transition can signal the existence of a transient quark-gluon plasma phase formed in a heavy-ion collision. The basis of the enhancement mechanism is the realization that antiquark densities are typically a factor 3 higher in the quark-gluon plasma phase than in hadronic matter at the same temperature and baryon density. The signal is improved by studying larger clusters of antimatter, i.e., light antinuclei like anti ..cap alpha.., in the central rapidity region. The effects of the transition dynamics and of the first order nature of the phase transition on the hadronization process are discussed.
Date: January 1, 1985
Creator: Heinz, U.; Subramanian, P.R. & Greiner, W.
System: The UNT Digital Library
Imaging techniques utilizing optical fibers and tomography (open access)

Imaging techniques utilizing optical fibers and tomography

Two-dimensional, time-dependent images generated by neutrons, gamma rays, and x-rays incident on fast scintillators are relayed to streak and video cameras over optical fibers. Three dimensions, two spatial and one temporal, have been reduced to two, one in space and time utilizing sampling methods permitting reconstruction of a time-dependent, two-dimensional image subsequent to data recording. The manner in which the sampling is done optimized the ability to reconstruct the image via a maximization of entropy algorithm. This method uses four linear fiber optic arrays typically 30 meters long and up to 35 elements each. A further refinement of this technique collapses the linear array information into four single fibers by wavelength multiplexing. This permits economical transmission of the data over kilometer distances to the recording equipment.
Date: January 1, 1985
Creator: Wilke, M.; King, N.S.P.; Gray, N.; Johnson, D.; Esquibel, D.; Nedrow, P. et al.
System: The UNT Digital Library
Determination of thorium and uranium at the nanogram per gram level in semiconductor potting plastics by neutron activation analysis (open access)

Determination of thorium and uranium at the nanogram per gram level in semiconductor potting plastics by neutron activation analysis

A method was developed to determine thorium and uranium in semiconductor potting plastics. The method is based on neutron activation and subsequent radiochemical separation to isolate and permit measurement of the induced /sup 233/Pa and /sup 239/Np. These plastics typically contain macro amounts of silicon, bromine and antimony and nanogram per gram amounts of thorium and uranium. The radiochemical method provides the necessary sensitivity and makes it possible to easily attain adequate decontamination of the tiny amounts of /sup 233/Pa and /sup 239/Np from the high levels of radioactive bromine and antimony. 8 refs.
Date: January 1, 1985
Creator: Dyer, F.F.; Emery, J.F. & Bate, L.C.
System: The UNT Digital Library
Magma energy (open access)

Magma energy

The paper briefly describes the potential magma resources in the US and worldwide, and possible ways of exploiting this resource. Two target sites for field experiments to characterize magma targets are identified: Long Valley Caldera and Coso Hot Springs. 11 refs. (ACR)
Date: January 1, 1985
Creator: Hardee, H.C.
System: The UNT Digital Library
Recent Developments in Microshell-Tipped Optical Fibers as High-Pressure Shock Detectors (open access)

Recent Developments in Microshell-Tipped Optical Fibers as High-Pressure Shock Detectors

We describe ongoing development and characterization of Microshell-tipped optical fibers used as impact sensors. We observed a risetime of 15 ns when the probe is used to measure a detonation wave in PETN. We report successful development of two nondestructive tests, radiography and fluorescence, to check the integrity of the sensor. The sensor is now commercially available. 5 refs., 3 figs.
Date: January 1, 1985
Creator: Mayer, F. J.; Maynard, R. L.; Musinski, D. L.; Schmerberg, N. W.; Wixom, M. R. & Benjamin, R. F.
System: The UNT Digital Library
Lung cancer in uranium miners and the implications of the U/V ratio in uranium-bearing particles (open access)

Lung cancer in uranium miners and the implications of the U/V ratio in uranium-bearing particles

Several geological formations mined for uranium ore during and after the second World War had been mined earlier for vanadium. Most miners and millers from the Utah-Colorado mining region worked with this ore or its tailings at one time or another. Preliminary investigation to determine the size and location of uranium-bearing particles retained in the lungs of a former uranium miner and miller from this region, who died of lung cancer (mesothelioma), showed a high nonuniform distribution of vanadium. This observation leads to the hypothesis that the vanadium content in that lung could be associated with inhaled particles. Further examination of spectra of characteristic x-rays obtained by scanning microPIXE (particle induced x-ray emission) of an autopsy sample of this lung indicated that vanadium was indeed present in localized sites within the 20 ..mu..m spatial resolution of the proton beam. This work points out that the vanadium found in the lungs of this former miner and miller is nonuniformly distributed, and can be used for site localization and size determination of inhaled particles retained in the lungs. The meaning of U/V ratios in dust particles and in lungs is discussed. Further studies are in progress to: (1) locate uranium-bearing particles in …
Date: January 1, 1985
Creator: Paschoa, A. S.; Wrenn, M. E.; Singh, N. P.; Bruenger, F. W.; Miller, S. C.; Cholewa, M. et al.
System: The UNT Digital Library
Review of high bandwidth fiber optics radiation sensors (open access)

Review of high bandwidth fiber optics radiation sensors

This paper summarizes the use of fiber optics or guided optical systems for radiation sensors. It is limited a passive systems wherein electrical is not required at the sensor location. However, electrically powered light sources, receivers and/or recorders may still be required for detection and data storage in sensor system operation. This paper emphasizes sensor technologies that permit high bandwidth measurements of transient radiation levels, and will also discuss several low bandwidth applications. 60 refs.
Date: January 1, 1985
Creator: Lyons, P. B.
System: The UNT Digital Library
Deconvolution analysis to determine relaxation time spectra of internal friction peaks (open access)

Deconvolution analysis to determine relaxation time spectra of internal friction peaks

A new method for analysis of an internal friction vs temperature peak to obtain an approximation of the spectrum of relaxation time responsible for the peak is described. This method, referred to as direct spectrum analysis (DSA), is shown to provide an accurate estimate of the distribution of relaxation times. The method is validated for various spectra, and it is shown that: (1) It provides approximations to known input spectra which replicate the position, amplitude, width and shape with good accuracy (typically 10%). (2) It does not yield approximations which have false spectral peaks.
Date: January 1, 1985
Creator: Cost, J.R.
System: The UNT Digital Library
Hot-cell design considerations for interfacing eddy-current systems (open access)

Hot-cell design considerations for interfacing eddy-current systems

The Hot Fuel Examination Facility/North conducts remote eddy-current examination of irradiated fuel elements. Applications include cladding breach detection and irradiation-induced ferrite examination. The seccussful use of remote eddy-current techniques is achieved by applying basic test parameters and interfacing considerations. These include impedance matching, operating frequency, and feedthrough considerations.
Date: January 1, 1985
Creator: Franklin, E. M.; Webb, J. P. & Larson, J. M.
System: The UNT Digital Library
Neutron diffraction studies of thin film multilayer structures (open access)

Neutron diffraction studies of thin film multilayer structures

The application of neutron diffraction methods to the study of the microscopic chemical and magnetic structures of thin film multilayers is reviewed. Multilayer diffraction phenomena are described in general and in particular for the case in which one of the materials of a bilayer is ferromagnetic and the neutron beam polarized. Recent neutron diffraction measurements performed on some interesting multilayer systems are discussed. 70 refs., 5 figs.
Date: January 1, 1985
Creator: Majkrzak, C.F.
System: The UNT Digital Library
Coherent anti-Stokes Raman scattering in benzene and nitromethane shock-compressed to 10 GPa (open access)

Coherent anti-Stokes Raman scattering in benzene and nitromethane shock-compressed to 10 GPa

The frequency shifts of the ring-stretching mode of shock-compressed liquid benzene and the CN stretching mode of nitromethane have been measured using coherent anti-Stokes Raman scattering. Shock pressures up to 11 GPa were achieved using a two-stage light gas gun. The frequency shifted Raman signal was generated using single pulse Nd:YAG and broadband-type lasers. 16 refs., 3 figs.
Date: January 1, 1985
Creator: Schmidt, S.C.; Moore, D.S.; Shaner, J.W.; Shampine, D.L. & Holt, W.T.
System: The UNT Digital Library
Electrorefining of uranium and plutonium from liquid cadmium (open access)

Electrorefining of uranium and plutonium from liquid cadmium

Feasibility of electrorefining of U, Pu, and mixtures thereof using a liquid Cd anode and a molten-salt electrolyte was investigated for the proposed pyrometallurgical process for the Integral Fast Reactor fuel. (DLC)
Date: January 1, 1985
Creator: Tomczuk, Z.; Poa, D. S.; Miller, W. E. & Steunenberg, R. K.
System: The UNT Digital Library
Effects of relay chatter in seismic probabilistic safety analysis (open access)

Effects of relay chatter in seismic probabilistic safety analysis

In the Zion and Indian Point Probabilistic Safety Studies, relay chatter was dismissed as a credible event and hence was not formally included in the analyses. Although little discussion is given in the Zion and Indian Point PSA documentation concerning the basis for this decision, it has been expressed informally that it was assumed that the operators will be able to reset all relays in a timely manner. Currently, it is the opinion of many professionals that this may be an oversimplification. The three basic areas which must be considered in addressing relay chatter include the fragility of the relays per se, the reliability of the operators to reset the relays and finally the systems response aspects. Each of these areas is reviewed and the implications for seismic PSA are discussed. Finally, recommendations for future research are given.
Date: January 1, 1985
Creator: Reed, J. W. & Shiu, K. K.
System: The UNT Digital Library