Cause of pitting in beryllium (open access)

Cause of pitting in beryllium

Light microscopy, bare-film radiography, secondary ion mass spectroscopy, electron microprobe and physical testing were used to examine beryllium specimens exhibiting a stratified, pitted, pattern after chemical milling. The objective was to find the cause of this pattern. Specimens were found to have voids in excess of density specification allowances. These voids are attributed, at least in part, to the sublimation of beryllium fluoride during the vacuum hot pressing operation. The origin of the pattern is attributed to these voids and etching out of fines and associated impurities. Hot isostatic pressing with a subsequent heat treatment close residual porosity and dispersed impurities enough to correct the problem.
Date: April 16, 1982
Creator: Kershaw, R. P.
System: The UNT Digital Library
Report of the Working Group on Media Accelerators (open access)

Report of the Working Group on Media Accelerators

A summary is given of the activities of those in the Media Accelerator Group. Attention was focused on the Inverse Cherenkov Accelerator, the Laser Focus Accelerator, and the Beat Wave Accelerator. For each of these the ultimate capability of the concept was examined as well as the next series of experiments which needs to be performed in order to advance the concept.
Date: April 12, 1982
Creator: Sessler, Andrew M.
System: The UNT Digital Library
Fusion breeder (open access)

Fusion breeder

The fusion breeder is a fusion reactor designed with special blankets to maximize the transmutation by 14 MeV neutrons of uranium-238 to plutonium or thorium to uranium-233 for use as a fuel for fission reactors. Breeding fissile fuels has not been a goal of the US fusion energy program. This paper suggests it is time for a policy change to make the fusion breeder a goal of the US fusion program and the US nuclear energy program. The purpose of this paper is to suggest this policy change be made and tell why it should be made, and to outline specific research and development goals so that the fusion breeder will be developed in time to meet fissile fuel needs.
Date: April 20, 1982
Creator: Moir, Ralph W.
System: The UNT Digital Library
Mine roof drill bits that save money (open access)

Mine roof drill bits that save money

Sandia National Laboratories, Albuquerque, NM, has developed advanced technology roof bolt drill bits which have demonstrated longer life, higher penetration rates at lower thrust and torque, and lower specific energy than conventional roof bolt drill bits. This is achieved through use of advanced technology cutting materials and novel bit body designs. These bits have received extensive laboratory and mine testing. Their performance has been evaluated and estimates of their value in reducing coal production costs have been made. The work was sponsored by the United States Department of Energy.
Date: April 1, 1982
Creator: Ford, L.M.
System: The UNT Digital Library
Sources of hot electrons in laser-plasma interaction with emphasis on Raman and turbulence absorption (open access)

Sources of hot electrons in laser-plasma interaction with emphasis on Raman and turbulence absorption

Heating targets with high power lasers results in a sizable fraction of the absorbed energy going into electrons of temperature much greater than thermal which can pre-heat the pellet core and accelerate fast ion blowoff which results in poor momentum transfer and hence poor compression efficiency. The present emphasis is to build lasers of higher frequency, ..omega../sub 0/, which at the same W/cm/sup 2/ results in more absorption into cooler electrons. Two physical reasons are that the laser can propagate to a higher electron density, n, infinity..omega../sub 0//sup 2/ resulting in more collisional inverse bremsstrahlung absorption proportional to n, and because the hot temperatures from some plasma absorption processes increase as the oscillatory velocity of an electron in the laser electric field v/sub 0//c = eE/(m/sub e/..omega../sub 0/). The heated electron temperatures from other plasma processes (Raman for example approx.(m/sub e//2)v/sup 2//sub phase/ and the higher laser frequency helps by increasing the competing collisional absorption and decreasing the Raman gain.
Date: April 6, 1982
Creator: Estabrook, K.; Kruer, W. L.; Phillion, D. W.; Turner, R. E. & Campbell, E. M.
System: The UNT Digital Library
UV dose-effect relationships and current protection exposure standards (open access)

UV dose-effect relationships and current protection exposure standards

In this paper we have attempted to quantify the health effects in man of uv-radiation exposure of wavelengths from 240 nm to 320 nm. Exposure to uv in this region could result in the formation of skin cancer or premature aging in man. The induction of cancer by uv radiation results from changes in genetic material. We have used the DNA action spectrum coupled with the uv skin cancer data available in the literature to derive the dose-effect relationships. The results are compared against the current uv protection standards.
Date: April 1, 1982
Creator: Singh, M.S. & Campbell, G.W.
System: The UNT Digital Library
Spectrum of the microwave background radiation (open access)

Spectrum of the microwave background radiation

A review is given of the present status of measurements of the spectrum of the microwave background. Factors which limit experimental accuracy are discussed with particular reference to high frequency measurements. A selection of the available measurements yields a data set which is reasonably consistent with the blackbody spectrum for a temperature of 2.9 K. A simple statistical analysis suggests either that there are errors in the data set, or that deviations from a blackbody spectrum exist. The difficulties inherent in property averaging the results from different observers are described. Prospects for improved measurements will be summarized.
Date: April 1, 1982
Creator: Richards, P.L.
System: The UNT Digital Library
Cancer risks and neutron RBE's from Hiroshima and Nagasaki (open access)

Cancer risks and neutron RBE's from Hiroshima and Nagasaki

The new radiation dose estimates for Hiroshima and Nagasaki are here combined with epidemiologic data from the A-bomb survivors and examined radiobiologically for compatability with other human and experimental data. The new doses show certain improvements over the original T65 doses. However, they suggest for chronic granulocytic leukemia, total malignancies, and chromosome aberrations, at neutron doses of 1 rad, RBEs in excess of 100, higher than expected from other findings. This and other indications suggest that either there are unrecognized systematic problems with the various radiobiological data, or the new doses are deficient in neutrons for Hiroshima, by a factor of about five. If in fact there were actually some 5-fold more dose from neutrons at Hiroshima than estimated by the new calculations, the RBEs would agree well with laboratory results, and other inconsistencies would largely disappear. Cancer risks are estimated for neutrons from the new doses and are compared with those estimated from radiobiologically reconciled doses (the new doses adjusted by adding approximately 5-fold more neutrons). The latter estimates appear more reasonable. For low-LET radiation, cancer risk estimates are altered very little by the new dose estimates for Nagasaki.
Date: April 30, 1982
Creator: Dobson, R.L. & Straume, T.
System: The UNT Digital Library
Updated estimates of /sup 239/ /sup 240/Pu + /sup 241/Am inventory, spatial pattern, and soil tonnage for removal at Nuclear Site-201, NTS (open access)

Updated estimates of /sup 239/ /sup 240/Pu + /sup 241/Am inventory, spatial pattern, and soil tonnage for removal at Nuclear Site-201, NTS

Updated estimates of /sup 239/ /sup 240/Pu + /sup 241/Am inventory and spatial pattern in surface soil are given for Nuclear Site (NS)-201 in Area 18 of the Nevada Test Site (NTS). These new estimates are based on 712 /sup 241/Am soil concentrations including 185 data values not previously available. Estimates were obtained using essentially the same Kriging techniques and the estimated average /sup 239/ /sup 240/Pu to /sup 241/Am ratio of 7.5 used by Simpson and Gilbert (1980) to obtain previous results. Estimated concentration contours, 68% confidence bands for the contours and estimated median concentrations for 50 x 50 ft blocks are given. The total Pu + Am inventory estimated to be in the top 5 cm of soil over the 109 hectare study (an area 5.2 hectares larger than used by Simpson and Gilbert, 1980) is approximately 16.3 curies. The approximate 68% confidence interval on this inventory estimate is about 6.7 to 45.6 curies. It is estimated that about 58 acres (approx. = 23 hectares) of land in the study are contaminated at levels greater than 40 pCi/g which includes about 40 acres (approx. = 16 hectares) at levels greater than 160 pCi/g. Approximately 28,000 tons of soil …
Date: April 1, 1982
Creator: Simpson, J. C. & Gilbert, R. O.
System: The UNT Digital Library
Role of rotational degrees of freedom in heavy-ion collisions (open access)

Role of rotational degrees of freedom in heavy-ion collisions

The degrees of freedom affected by the angular momentum are identified. The relevance of the equilibrium fluctuations in a diffusive evolution of the system is discussed. The statistical limit is described and chosen as a reference for comparing with experiment. The rigid rotation regime is shown to be reached in a variety of reactions. The fragment spin alignment is measured from ..gamma..-ray multiplicities and anisotropies as well as from sequential fission angular distributions. Good agreement is obtained with the statistical model for the P/sub zz/ component of the polarization tensor. The P/sub xy/ component seems also to reach the statistical limit at large Q-value. The effect of shells on the angular momentum transferred to the fragments and on its misalignment is discussed theoretically and specific predictions are made.
Date: April 1, 1982
Creator: Moretto, Luciano G.
System: The UNT Digital Library
Some effects of the transverse-stability requirement on the design of a grating linac (open access)

Some effects of the transverse-stability requirement on the design of a grating linac

The transverse stability of the grating linac proposed by Palmer is analyzed. It is shown that an open structure such as a grating is always unstable transversely as long as it is uniform. The structure can be made stable by utilizing the strong focusing principle. This is achieved by periodically interrupting the grating shape. We analyze the strong focusing grating linac, and find that the stability requirement places a non-trivial constraint on the phase acceptance of the system.
Date: April 1, 1982
Creator: Kim, K. J. & Kroll, N. M.
System: The UNT Digital Library
Dynamic positron emission tomography in man using small bismuth germanate crystals (open access)

Dynamic positron emission tomography in man using small bismuth germanate crystals

Primary considerations for the design of positron emission tomographs for medical studies in humans are the need for high imaging sensitivity, whole organ coverage, good spatial resolution, high maximum data rates, adequate spatial sampling with minimum mechanical motion, shielding against out of plane activity, pulse height discrimination against scattered photons, and timing discrimination against accidental coincidences. We discuss the choice of detectors, sampling motion, shielding, and electronics to meet these objectives.
Date: April 1, 1982
Creator: Derenzo, S.E.; Budinger, T.F.; Huesman, R.H. & Cahoon, J.L.
System: The UNT Digital Library
Workshop on nuclear dynamics (open access)

Workshop on nuclear dynamics

Separate abstracts were prepared for the 25 papers presented. (WHK)
Date: April 1, 1982
Creator: unknown
System: The UNT Digital Library
Incorporation of high-level wastes in SYNROC: results from recent process-engineering studies at Lawrence Livermore National Laboratory (open access)

Incorporation of high-level wastes in SYNROC: results from recent process-engineering studies at Lawrence Livermore National Laboratory

In this paper, highlights from recent engineering research and development, in particular, results from fluidized bed calcination studies of SYNROC slurry are summarized. A schematic diagram of the envisioned SYNROC process (at this stage of development) is also presented. It shows the use of a fluidized bed calciner to prepare SYNROC powder that is then fed to a storage hopper. Bellows-type canisters are filled, evacuated, sealed and preheated. The preheated canisters are loaded into a hot isotactic pressing unit where they are densified, then removed and cooled and finally loaded into a waste storage container. After sealing, this container is decontaminated and transferred to the interim storage facility and then, ultimately, to an underground repository.
Date: April 15, 1982
Creator: Campbell, J. H.; Hoenig, C. L.; Ackerman, F. J.; Peters, P. E. & Grens, J. Z.
System: The UNT Digital Library
Recent results from Mark II at SPEAR and PEP (open access)

Recent results from Mark II at SPEAR and PEP

Three results are presented: (1) The semi-leptonic branching ratio of the ..lambda../sub c/ has been measured at SPEAR to be B(..lambda../sub c//sup +/ ..-->.. e/sup +/X) = (4.5 +- 1.7)%. (2) Properties of tau-pair production have been measured at PEP at square root S = 29 GeV: sigma/sup tau tau//sigma/sup QED/ = 0.97 +- 0.05 +- 0.06; the forward-backward asymmetry is A/sub tau tau/ = (-3.5 +- 5.0)%; inclusive branching ratios are B(tau ..-->.. 1 Prong) = (86 +- 4)%, B(tau ..-->.. 3 Prongs) = (14 +- 4)%, B(tau ..-->.. 5 Prongs) < 0.6% (95% C.L.). (3) A search has been performed for the pair production of charged, point-like, spin 0 particles. The existence of such particles can be ruled out at a 90% confidence level for 3 approx. < M approx. < 10 GeV/c/sup 2/ and branching ratio into hadrons approx. < 90%.
Date: April 1, 1982
Creator: Strait, J.
System: The UNT Digital Library
Portable, remotely operated, computer-controlled, quadrupole mass spectrometer for field use (open access)

Portable, remotely operated, computer-controlled, quadrupole mass spectrometer for field use

A portable, remote-controlled mass spectrometer was required at the Nevada Test Site to analyze prompt post-event gas from the nuclear cavity in support of the underground testing program. A Balzers QMG-511 quadrupole was chosen for its ability to be interfaced to a DEC LSI-11 computer and to withstand the ground movement caused by this field environment. The inlet system valves, the pumps, the pressure and temperature transducers, and the quadrupole mass spectrometer are controlled by a read-only-memory-based DEC LSI-11/2 with a high-speed microwave link to the control point which is typically 30 miles away. The computer at the control point is a DEC LSI-11/23 running the RSX-11 operating system. The instrument was automated as much as possible because the system is run by inexperienced operators at times. The mass spectrometer has been used on an initial field event with excellent performance. The gas analysis system is described, including automation by a novel computer control method which reduces operator errors and allows dynamic access to the system parameters.
Date: April 1, 1982
Creator: Friesen, R.D.; Newton, J.C. & Smith, C.F.
System: The UNT Digital Library
Role of human- and animal-sperm studies in the evaluation of male reproductive hazards (open access)

Role of human- and animal-sperm studies in the evaluation of male reproductive hazards

Human sperm tests provide a direct means of assessing chemically induced spermatogenic dysfunction in man. Available tests include sperm count, motility, morphology (seminal cytology), and Y-body analyses. Over 70 different human exposures have been monitored in various groups of exposed men. The majority of exposures studied showed a significant change from control in one or more sperm tests. When carefully controlled, the sperm morphology test is statistically the most sensitive of these human sperm tests. Several sperm tests have been developed in nonhuman mammals for the study of chemical spermatotoxins. The sperm morphology test in mice has been the most widely used. Results with this test seem to be related to germ-cell mutagenicity. In general, animal sperm tests should play an important role in the identification and assessment of potential human reproductive hazards. Exposure to spermatotoxins may lead to infertility, and more importantly, to heritable genetic damage. While there are considerable animal and human data suggesting that sperm tests may be used to detect agents causing infertility, the extent to which these tests detect heritable genetic damage remains unclear. (ERB)
Date: April 7, 1982
Creator: Wyrobek, A.J.; Gordon, L. & Watchmaker, G.
System: The UNT Digital Library
Predictive methodology for supply disruptions (open access)

Predictive methodology for supply disruptions

Energy supply disruptions do not suddenly arise in a full-blown fashion. Lags in the energy system provide a time horizon which allows for the prediction of a possible supply problem. A simple model is described which can be used to provide a set of indicators for the possible onset of an energy emergency. The methodology was tested on the gasoline shortage of 1979, and the results are presented.
Date: April 1, 1982
Creator: Beller, M. & D'Acierno, J.
System: The UNT Digital Library
Carcinogenesis and low-level ionizing radiation with special reference to lung cancer and exposure to radon daughters (open access)

Carcinogenesis and low-level ionizing radiation with special reference to lung cancer and exposure to radon daughters

Of the important health effects of ionizing radiation, three important late effects - carcinogenesis, teratogenesis and mutagenesis are of greatest concern. This is because any exposure, even at low levels, carries some risk of such deleterious effects. As the dose of radiation increases above very low levels, the risk of health effects increases. Cancer-induction is the most important late somatic effect of low-dose ionizing radiation. Solid cancers, rather than leukemia, are principal late effects in exposed individuals. Tissues vary greatly in their susceptibility to radiation carcinogenesis. The most frequently occurring radiation-induced cancers in man include, in decreasing order of susceptibility: the female breast, the thyroid gland, the blood-forming tissues, the lung, certain organs of the gastrointestinal tract, and the bones. A number of biological and physical factors affect the cancer risk, such as age, sex, life-style, LET, and RBE. Despite uncertainty about low-level radiation risks, regulatory and advisory bodies must set standards for exposure, and individuals need information to be able to make informed judgments for themselves. From the point of view of the policy maker, the overriding concern is the fact that small doses of radiation can cause people to have more cancers than would otherwise be expected. While …
Date: April 1, 1982
Creator: Fabrikant, Jacob I.
System: The UNT Digital Library
Calorimetry in superfluid He II to measure losses in superconducting magnets (open access)

Calorimetry in superfluid He II to measure losses in superconducting magnets

A method using calorimetry to measure magnet losses in pressurized Helium II is described. The isothermal nature of He II is used in measuring the overall heat capacity of the system and the net refrigeration power. During the measurements, the refrigeration power is held fixed, and the system (400 liters) temperature is near 1.92 K. The calorimetric measurement was calibrated against known power inputs between 1 and 20 W. This technique can even measure heat loads higher than the available refrigeration. Results of loss measurement on two dipole magnets are reported.
Date: April 1, 1982
Creator: Caspi, S.
System: The UNT Digital Library
Simple home-made sensors for potentiometric titrations. [Nitroform CH(NO/sub 2/)/sub 3/] (open access)

Simple home-made sensors for potentiometric titrations. [Nitroform CH(NO/sub 2/)/sub 3/]

A sensor for potentiometric titrations was prepared by coating a spectroscopic graphite rod with a solution of poly(vinyl chloride) and dioctyphthalate in tetrahydrofuran. The reference electrode was an Ag/AgCl single-junction electrode. The sensor was used in precipitation, acid-base, compleximetric, and redox titrations. Preparation of the coated-graphite sensor is simple and rapid. Moreover, it is quite inexpensive. A limitation is its applicability in aqueous media only, because organic solvents will dissolve the membrane. Various uncoated types of graphite have also been investigated as sensors, particularly in two applications of interest in the analysis of propellants: the titration of nitroform and perchlorate. Obviously, these sensors can be used also in nonaqueous, or partially nonaqueous media. These sensors may also find use in the potentiometric titration of fluoride vs La(III) or Th(IV).
Date: April 1, 1982
Creator: Selig, W.
System: The UNT Digital Library
On-Shore Processing (open access)

On-Shore Processing

A proposal is made to use a fast trigger processor to utilize the data acquisition system proposed at this workshop.
Date: April 1, 1982
Creator: Theriot, D.; Brenner, A. E.; Dau, W. D.; Geelhood, B. D.; Harris, F.; Learned, J. G. et al.
System: The UNT Digital Library
Sensitivity of a Laser-Driven-Grating Linac to Grating Errors (open access)

Sensitivity of a Laser-Driven-Grating Linac to Grating Errors

The effect of grating errors on transverse beam stability is analyzed. We characterize grating errors by random groove displacements and find that transverse displacements due to such errors approach limiting values of the same order as the grating displacements themselves. It therefore appears that transverse stability requirements will not impose unusually stringent precision requirements on the grating structure.
Date: April 1, 1982
Creator: Kroll, N. M.
System: The UNT Digital Library
Modeling of nuclear waste disposal by rock melting (open access)

Modeling of nuclear waste disposal by rock melting

Today, the favored option for disposal of high-level nuclear wastes is their burial in mined caverns. As an alternative, the concept of deep disposal by rock melting (DRM) also has received some attention. DRM entails the injection of waste, in a cavity or borehole, 2 to 3 kilometers down in the earth crust. Granitic rocks are the prime candidate medium. The high thermal loading initially will melt the rock surrounding the waste. Following resolidification, a rock/waste matrix is formed, which should provide isolation for many years. The complex thermal, mechanical, and hydraulic aspects of DRM can be studied best by means of numerical models. The models must accommodate the coupling of the physical processes involved, and the temperature dependency of the granite properties, some of which are subject to abrupt discontinuities, during ..cap alpha..-..beta.. phase transition and melting. This paper outlines a strategy for such complex modeling.
Date: April 1, 1982
Creator: Heuze, F.E.
System: The UNT Digital Library