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High repetition rate burst-mode spark gap

Description: Results are presented on the design and testing of a pressurized gas blown spark gap switch capable of high repetition rates in a burst mode of operation. The switch parameters which have been achieved are as follows: 220-kV, 42-kA, a five pulse burst at 1-kHz, 12-ns risetime, 2-ns jitter at a pulse width of 50-ns.
Date: June 15, 1978
Creator: Faltens, A.; Reginato, L.; Hester, R.; Chesterman, A.; Cook, E.; Yokota, T. et al.
Partner: UNT Libraries Government Documents Department

Shiva laser system performance

Description: On November 18, 1977, after four years of experimentation, innovation, and construction, the Shiva High Energy Laser facility produced 10.2 kJ of focusable laser energy delivered in a 0.95 ns pulse. The Shiva laser, with its computer control system and delta amplifiers, demonstrated its versatility on May 18, 1978, when the first 20-beam target shot with delta amplifiers focused 26 TW on a target and produced a yield of 7.5 x 10/sup 9/ neutrons.
Date: June 15, 1978
Creator: Glaze, J.; Godwin, R.O. & Holzrichter, J.F.
Partner: UNT Libraries Government Documents Department

Development of fast neutron spectrometer system for study of short-lived nuclides important to the decay heat problem. Final report, July 15, 1977--December 31, 1977. UCB-ENG-4485

Description: The objectives of this study were (a) to develop techniques for measurement of delayed neutron spectra with resolutions approaching 8.0 keV at the thermal peak and (b) to explore techniques for measuring gamma rays and neutrons in coincidence. During the contract period the following have been accomplished: (a) the electronic, acoustical and inherent noise characteristics of the 3 He neutron ionization chambers purchased from SEFORAD, LTD have been characterized. Through construction of an acoustical shield and replacement of several components at the input stage of the preamplifiers associated with the detectors, the resolutions of the spectrometers have been improved by about 10 to 15 percent and the environment has been controlled to permit maintenance of the improved resolution under normal laboratory conditions. The resolution of the best spectrometer is now 9.3 keV; (b) it has been shown that the amplitude and resolution for neutrons from a thermalized Pu-Be source are dependent upon pulse risetime. For the risetime range 0.2--1.2 ..mu..s, the amplitudes of pulses were found to vary by 0.7 to 0.8 keV and the longer risetime pulses led to a full energy peak narrower than that from the short risetime pulses by about 0.2 keV. (c) based on the information available in the literature on the Fano Factors of gas mixtures approximating that existing in the spectrometers, and the measurements made on one of the detectors, it was concluded that external factors are still contributing significantly to the resolution and that it should be possible to obtain a resolution of near 8.0 keV with no change in the gas mixture; (d) the principal limitation in the use of the /sup 3/He spectrometers for neutron--gamma ray coincidence measurements lies in the long times required for drift of electrons from the site of interaction in the device to the grid surrounding ...
Date: April 15, 1978
Creator: Prussin, S.G.
Partner: UNT Libraries Government Documents Department

Uranium miner lung cancer study. Progress report for period, July 1, 1977--July 1 1978

Description: This study was initiated in 1957 by the U.S. Public Health, and many facets of this project are reaching final objectives. Many new studies have developed in the course of this study and will continue. The projects supported by The Department of Energy during the past year are of utmost importance and consist of: (a) collection of material from uranium miners known to have cancer of the lung into a tumor registry; (b) completion and publication of the Manual on Pulmonary Cytology; (c) regression study of sputum cytological findings in uranium miners who showed marked atypical squamous cell metaplasia and have quit smoking cigarettes, mining, or both; (d) continuation of sputum collection and collection of lungs from deceased miners; (e) sensory development for localization of carcinoma in situ of the lung; and (f) lung histology program. Since we have examined approximately 80,000 sputum samples the last 21 years in cases that showed normal cytology at the inception of the study and some subsequently developed carcinoma of the lung, we have an accumulation of material that is worthy of study and presentation. In addition, we continue to add new knowledge to the art of diagnostic pulmonary cytology. This is a relatively new field, and our contributions resulting from these studies have added much to this new diagnostic tool.
Date: September 15, 1978
Creator: Saccomanno, G.
Partner: UNT Libraries Government Documents Department

Motion of particles in a thermal boundary layer

Description: In the course of using laser Doppler velocimetry to study combustion in a thermal boundary layer, the particle count rate was found to decrease abruptly to zero inside the boundary layer. Experimental and theoretical investigation of this phenomenon was carried out. The motion of the particles may be due to the combined effects of thermophoresis and radiative heating.
Date: June 15, 1978
Creator: Schefer, R.W.; Agrawal, Y.; Cheng, R.K.; Robben, F. & Talbot, L.
Partner: UNT Libraries Government Documents Department

Modulator charging system upgrade for a 5-MeV electron accelerator

Description: The Lawrence Livermore Laboratory is currently constructing a new linear induction accelerator with a higher beam current than the Astron accelerator. The new accelerator, called the Experimental Test Accelerator (ETA) will be a 5-MeV, 10-kA accelerator with a pulse width of 50-ns. Like the Astron, the principle of magnetic induction is used to obtain a linear accelerator. The modular accelerating cavities form essentially a 1:1 transformer and the change in flux in the ferrite core induces an axial electric field for the acceleration of electrons. Since the total energy storage for the ETA is much greater than the requirement for Astron, the power system, the capacitor bank and the modulator charging system all had to be modified to provide an overall regulation of .1%. This strict regulation of the charging voltage is necessary for pulse-to-pulse repeatability.
Date: June 15, 1978
Creator: Rogers, D.; Dexter, W.; Myers, A.; Reginato, L. & Zimmerman, A.
Partner: UNT Libraries Government Documents Department

Influence of organic matter on trace metal flux in coastal sediments. [Sequim Bay]

Description: These studies indicate that organic matter in coastal sediment constitutes a primary sink for trace metals, both at natural and amended levels. Organic substances are also involved in controlling the mobility and flux of trace metals from sediments. Further, organically-bound trace metals in sediments appear to be an important source to deposit-feeding organisms.
Date: May 15, 1978
Creator: Schmidt, R.L. & Gibson, C.I.
Partner: UNT Libraries Government Documents Department

MACK/MACKLIB system for nuclear response functions

Description: The MACK computer program calculates energy pointwise and multigroup nuclear response functions from basic nuclear data in ENDF/B format. The new version of the program MACK-IV, incorporates major developments and improvements aimed at maximizing the utilization of available nuclear data and ensuring energy conservation in nuclear heating calculations. A new library, MACKLIB-IV, of nuclear response functions was generated in the CTR energy group structure of 171 neutron groups and 36 gamma groups. The library was prepared using MACK-IV and ENDF/B-IV and is suitable for fusion, fusion-fission hydrids, and fission applications.
Date: March 15, 1978
Creator: Abdou, M.A. & Gohar, Y.M.
Partner: UNT Libraries Government Documents Department

Energy and protein production from pulp mill wastes. Progress report, June 15, 1978--September 15, 1978

Description: During the past quarter significant progress was achieved in increasing yeast protein production from ozonated desugared spent sulfite liquor (OSSL). In addition, the prime factors influencing the rate of methanogenesis of OSSL were studied in depth with two factors appearing to be dominate. Continuous fermentation experiments made to corobborate earlier batch studies achieved yields of 5.0 g/1 of yeast cells at a residence time of 1.8 days. Improved strain selection and increased aeration rate were responsible for the approximate doubling of prior productivities. All experiments were conducted on DSSL which had been ozonated with 0.8 g/1. This value appears to be close to optimum. The most important parameters influencing the rate of methanogenesis in continuous fermentation appear to be the microflora, sufficient trace growth factors, and adequate precursor concentrations. Although efforts to date at independently varying these three parameters have been unsuccessful, outstanding results have been obtained when the three were varied concurrently. Methane rates which averaged 8 cc/hr were increased to over 100 cc/hr in several exploratory experiments. A concerned effort will be expended during the next quarter to identify the exact parameter responsible for the order of magnitude increase in productivity.
Date: September 15, 1978
Creator: Jurgensen, M.F. & Patton, J.T.
Partner: UNT Libraries Government Documents Department

Modeling vertical loads in pools resulting from fluid injection. [BWR]

Description: Table-top model experiments were performed to investigate pressure suppression pool dynamics effects due to a postulated loss-of-coolant accident (LOCA) for the Peachbottom Mark I boiling water reactor containment system. The results guided subsequent conduct of experiments in the /sup 1///sub 5/-scale facility and provided new insight into the vertical load function (VLF). Model experiments show an oscillatory VLF with the download typically double-spiked followed by a more gradual sinusoidal upload. The load function contains a high frequency oscillation superimposed on a low frequency one; evidence from measurements indicates that the oscillations are initiated by fluid dynamics phenomena.
Date: June 15, 1978
Creator: Lai, W. & McCauley, E.W.
Partner: UNT Libraries Government Documents Department

Development of a practical photochemical energy storage system. Quarterly report

Description: A study of a series of copper(I) compounds which contain a strongly absorbing chromophore (e.g., CuBr(PPh/sub 3/)-(2,2'-bipyridine)) for use as sensitizers in photochemical energy storage systems is described. The generally low sensitization efficiencies of these compounds preclude their use as sensitizers in a practical photochemical energy storage system. Nevertheless, some interesting mechanistic information has emerged from this study, the full details of which are being written for publication. Also, the related compound, Ru(bipy)/sub 2/(NBD)/sup +2/, which features a norbornadiene molecule coordinated directly to a strongly absorbing metal containing fragment was examined. The original rationale for studying this compound was the expectation that the absorption of visible light would result in the population of an electronically excited state in which the electron density of the NBD is considerably perturbed. Relaxation of this state could then occur by a pathway which leads to the rearranged product, quadricyclene. It was found, however, that the sensitization efficiency of this compound is quite low. A comprehensive study of the factors which affect the sensitization efficiencies of Ir(bipy)/sub 2/(bipy')OH/sub 2//sup +3/ is unerway. In order to elucidate the mechanism(s) by which organic sensitizers affect the conversion of norbornadiene to quadricyclene, a study to measure the actual rate constant for the sensitization process is underway. The status of the project is discussed.
Date: September 15, 1978
Creator: Hautala, R.R. & Kutal, C.R.
Partner: UNT Libraries Government Documents Department

Average neutralization and transverse stability in ISABELLE

Description: Clearing of electrons in the vicinity of the axis of a proton beam in the dipoles of a separated function AG-focusing structure is accomplished by transverse crossed-field drift due to the magnetic dipole field and a weak longitudinal electric field. This electric field is generated by potential differences caused by cross section variations of the beam due to variations of the ..beta..-functions and dispersion. The resulting radial drift brings the electrons into the off-axis region where they are driven out of the magnets by the usual longitudinal cross-field drift caused by the radial space charge field. The neutralization in ISABELLE is then a factor 20 below former estimates, and transverse stability can be obtained by chromaticity adjustments well within the design strengths of the sextupole correction windings.
Date: December 15, 1978
Creator: Herrera, J & Zotter, B
Partner: UNT Libraries Government Documents Department

Experimental test facility for evaluation of solar control strategies

Description: An experimental solar heating and cooling system has been constructed at LBL. It was designed to serve as a test system to check out the operation of an LBL-developed solar controller that looked promising in terms of its commercialization potential. Improvements were made in the experimental heating and cooling system to enable quantitative determination of the auxiliary energy savings made possible by using this type of controller. These improvements consisted of installation and calibration of accurate instrumentation, data acquisition capabilities, and development of simulated input and output devices that would allow repeated experiments using the same running conditions. In addition, the possibilities of further development of the heating and cooling system into an experimental test facility for a wide range of solar control strategies have been investigated.
Date: August 15, 1978
Creator: Majteles, M.; Lee, H.; Wahlig, M. & Warren, M.
Partner: UNT Libraries Government Documents Department

Enhanced safety in the storage of fissile materials. [Boron-loaded epoxy resin]

Description: An inexpensive boron-loaded liner of epoxy resin for fissile-material storage containers was developed that can be easily fabricated of readily available, low-cost materials. Computer calculations indicate reactivity will be reduced substantially if this neutron-absorbing liner is added to containers in a typical storage array. These calculations compare favorably with neutron-attenuation experiments with thermal and fission neutron spectra, and tests at the Fire Test Facility indicate the epoxy resin will survive extreme environmental and accident conditions. The fire-resistant and insulating properties of the epoxy-resin liner further augment its ability to protect fissile materials. Boron-loaded epoxy resin is adaptable to many tasks but is particularly useful for providing enhanced criticality safety in the packaging and storage of fissile materials.
Date: December 15, 1978
Creator: Williams, G.E. & Alvares, N.J.
Partner: UNT Libraries Government Documents Department