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[Document with Handwritten Notes: AIDS ARMS Network] (open access)

[Document with Handwritten Notes: AIDS ARMS Network]

A summary of caseload statistics from the AIDS ARMS Network listing out the number of clients and information about those clients. This document is followed by a map.
Date: December 1, 1986
Creator: AIDS ARMS Network
Object Type: Text
System: The UNT Digital Library
Development of thin foils for use in generating neutral particle beams (open access)

Development of thin foils for use in generating neutral particle beams

The Isotope Research Materials Laboratory (IRML) was requested to prepare large-area, ultrathin aluminum and carbon foils for use in beam neutralization experiments. There were two major parts to this request. The first was to immediately provide a number of 5-cm-dia foils 5 to 20 ..mu..g/cm/sup 2/ thick for use in experiments at the Fusion Materials Irradiation Test (FMIT) facility and at Argonne National Laboratory (ANL). The second, longer-term request was to develop methods to prepare 25-cm x 25-cm, 10-..mu..g/cm/sup 2/ aluminum neutralizer foils. Both parts of the request have been successfully met.
Date: January 1, 1986
Creator: Aaron, W. S.; Zevenbergen, L. A.; Adair, H. L.; Culpepper, C. A.; McCulla, W. H.; Nolan, T. A. et al.
Object Type: Article
System: The UNT Digital Library
Preparation of thin films for use in generating neutral particle beams (open access)

Preparation of thin films for use in generating neutral particle beams

Large-area, thin aluminum foils were prepared for use in beam neutralization experiments. The foils were made using either electron beams of resistance heating. Foil thickness and uniformity were determined using alpha particles. The foils perform very well when bombarded by energetic H/sup -/ ions. (DLC)
Date: January 1, 1986
Creator: Aaron, W.S.; Zevenbergen, L.A. & Adair, H.L.
Object Type: Article
System: The UNT Digital Library
Limit on tau neutrino mass (open access)

Limit on tau neutrino mass

Using the complete data sample of 300 pb/sup -1/ collected by the HRS spectrometer in e/sup +/e/sup -/ collisions at 29 GeV, mass limit for the tau neutrino is set. The end point of the hadronic mass spectrum is determined in the decays tau ..-->.. 5..pi../sup + -/nu/sub tau/ and tau ..-->.. 5..pi../sup + -/..pi../sup 0/nu/sub tau/. At 95% confidence level, an upper limit of M/sub nu/sub tau// < 76 MeV/c/sup 2/, is found. 8 refs., 4 figs.
Date: January 1, 1986
Creator: Abachi, S.; Akerlof, C.; Baringer, P.; Beltrami, I.; Blockus, D.; Bonvicini, G. et al.
Object Type: Article
System: The UNT Digital Library
Charm D production in e/sup +/e/sup -/ annihilation at 29 GeV (open access)

Charm D production in e/sup +/e/sup -/ annihilation at 29 GeV

Results are presented on the analysis of charm D Production from 300 pb/sup -1/ of data taken with the HRS Detector at PEP. The electroweak asymmetry is -8.4 +- 3.6% and R (D + D*) = 1.57 +- 0.17. Fragmentation functions for D/sup 0/, D/sup +/, D*/sup +/ production and the results of a search for the D** are given. 10 refs., 9 figs.
Date: January 1, 1986
Creator: Abachi, S.; Akerlof, C.; Baringer, P.; Blockus, D.; Brabson, B.; Brom, J. M. et al.
Object Type: Article
System: The UNT Digital Library
Limit on tau decay to 7-charged tracks (open access)

Limit on tau decay to 7-charged tracks

Using the complete data sample of 300 pb/sup -1/ from e/sup +/e/sup -/ collisions at 29 GeV, the HRS collaboration has searched for tau decay to 7 charged particles and any number of neutrals. No events were found. The corresponding upper limit to the branching ratio is B(tau ..-->.. 7..pi../sup + -/ + n..gamma.. + nu/sub tau/) < 3.8 x 10/sup -4/ at 90% confidence level. Using the final HRS data sample we also report updated branching ratios for tau ..-->.. 5..pi../sup + -/ + nu/sub tau/ and tau ..-->.. 5..pi../sup + -/ + ..pi../sup 0/ + nu/sub tau/.
Date: January 1, 1986
Creator: Abachi, S.; Akerlof, C.; Baringer, P.; Blockus, D.; Brabson, B.; Brom, J. M. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the D/sup 0/ meson lifetime (open access)

Measurement of the D/sup 0/ meson lifetime

We report the measurement of the lifetime of the D/sup 0/ meson. The direct observation of the decay vertex distribution in the process D/sup 0/ ..-->.. K/sup -/..pi../sup +/ was made using a vertex chamber installed in the HRS detector at PEP. The measured lifetime is found to be tau/sub D/sup 0// = .42 +- .09 +- .06ps. 5 refs., 4 figs.
Date: January 1, 1986
Creator: Abachi, S.; Akerlof, C.; Baringer, P.; Blockus, D.; Brabson, B.; Brom, J. M. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the electroweak asymmetry in the reaction e/sup +/e/sup -/. -->. tau/sup +/tau/sup -/ at 29 GeV (open access)

Measurement of the electroweak asymmetry in the reaction e/sup +/e/sup -/. -->. tau/sup +/tau/sup -/ at 29 GeV

This paper reports the electroweak asymmetry in the reaction e/sup +/e/sup -/ ..-->.. tau/sup +/tau/sup -/ at 29 GeV. The results came from data taken with the High Resolution Spectrometer at PEP corresponding to an integrated luminosity of 256 pb/sup -1/. The 7372 observed events give A/sub tau tau/ = -(4.4 +- 1.4 +- 0.5)%. Events selected in the central region of the detector measure a total cross section of R/sub tau tau/ = 1.06 +- 0.02 +- 0.04. 5 refs., 1 fig.
Date: June 1, 1986
Creator: Abachi, S.; Akerlof, C.; Baringer, P.; Blockus, D.; Brabson, B.; Brom, J. M. et al.
Object Type: Article
System: The UNT Digital Library
Multiplicity distributions in e/sup +/e/sup -/ annihilation at 29 GeV: a comparison with hadronic data (open access)

Multiplicity distributions in e/sup +/e/sup -/ annihilation at 29 GeV: a comparison with hadronic data

The charged particle multiplicity distributions for single jets in e/sup +/e/sup -/ annihilation at 29 GeV have been measured using the High Resolution Spectrometer at PEP. The shape of the distribution agrees well with a Poisson distribution. No correlation is observed between the multiplicities in the two jets of an event. For fixed values of the prong number of the total event, the multiplicity sharing between the two jets is in good agreement with a binomial distribution. These observations are contrasted to the results from soft hadronic collisions and conclusions are drawn about the nature of clusters. 21 refs., 4 figs.
Date: June 1, 1986
Creator: Abachi, S.; Akerlof, C.; Baringer, P.; Blockus, D.; Brabson, B.; Brom, J. M. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the tau lepton lifetime (open access)

Measurement of the tau lepton lifetime

We report the measurement of the lifetime of the tau lepton. This measurement was made using the HRS spectrometer at PEP, operating at 29 GeV. The 3 prong decay vertices were measured using a four layer tubular cell vertex chamber. The lifetime of the tau was determined to be tau/sub tau/ = .28 +- .02 +- .02 ps. 7 refs., 3 figs.
Date: January 1, 1986
Creator: Abachi, S.; Akerlof, C.; Baringer, P.; Blockus, D.; Brabson, B.; Brom, J.M. et al.
Object Type: Report
System: The UNT Digital Library
lambda. production in e/sup +/e/sup -/ annihilations at 29 GeV (open access)

lambda. production in e/sup +/e/sup -/ annihilations at 29 GeV

This paper presents measurements of the inclusive production cross sections of ..lambda.. baryons in e/sup +/e/sup -/ annihilations at ..sqrt..s = 29 GeV. The data sample corresponds to an integrated luminosity of 256 pb/sup -1/ collected with the High Resolution Spectrometer at PEP. Comparisons are made to the predictions of the Lund model. The data are well described using a strange diquark suppression parameter, (us/ud)/(s/d), of 0.89 +- 0.10/sub -0.16//sup +0.56/, and the measured ..lambda../sub c/ ..-->.. ..lambda.. + X branching ratio of 23 +- 10%. No polarization is observed in the ..lambda.. decays. 17 refs., 5 figs.
Date: May 1, 1986
Creator: Abachi, S.; Baringer, P.; Beltrami, I.; Bylsma, B.G.; DeBonte, R.; Koltick, D. et al.
Object Type: Article
System: The UNT Digital Library
Observation of tensor and scalar mesons produced in e/sup +/e/sup -/ annihilation at 29 GeV (open access)

Observation of tensor and scalar mesons produced in e/sup +/e/sup -/ annihilation at 29 GeV

The production of the tensor mesons, integral/sup 0/(1270) and K*/sup 0/(1430), and the scalar meson S(975) have been observed in e/sup +/e/sup -/ annihilation at 29 GeV center of mass energy, using data obtained with the HRS detector at the PEP storage ring. The mean multiplicities for meson momenta greater than 1450 MeV/c are <n/sub f/sup 0//> = 0.11 +- 0.04, <n/sub K*/sup 0/(1430)/> = 0.10 +- 0.06, and <n/sub S/> = 0.05 +- 0.02 per hadronic event. The fragmentation functions of the tensor mesons are in good agreement with the predictions of the Webber cluster model. The possibility of a large strange quark component in the S meson structure is suggested by the data.
Date: January 1, 1986
Creator: Abachi, S.; Baringer, P.; Bylsma, B. G.; DeBonte, R.; Koltick, D.; Loeffler, F. J. et al.
Object Type: Article
System: The UNT Digital Library
Physical inventory verification exercise for a highly enriched uranium fabrication facility (open access)

Physical inventory verification exercise for a highly enriched uranium fabrication facility

The International Atomic Energy Agency, in collaboration with the US Support Program (POTAS), has developed and conducted a training exercise simulating a physical inventory verification (PIV) at a highly enriched uranium (HEU) fabrication facility. This exercise is part of a series sponsored by the POTAS program, including PIVs at light-water reactors and plutonium fabrication facilities. The first HEU exercise took place in September 1985 at Los Alamos National Laboratory and a second is scheduled for Spring, 1987 at JRC, ISPRA. The main objectives of these exercises are: to provide the opportunity for inspectors to test and evaluate the use of nondestructive assay (NDA) equipment and computer software under conditions similar to those found during actual inspections; to use the data generated to evaluate different inspection procedures and strategies; and to exchange ideas on PIV procedures between the three operations divisions. Because the exercises are conducted in a neutral environment, free of the time pressure often found in actual inspections, it is possible for the inspectors to achieve the course objectives.
Date: January 1, 1986
Creator: Abedin-Zadeh, R. & Augustson, R.H.
Object Type: Article
System: The UNT Digital Library
Technology development for the design of shallow land burial facilities at semiarid sites (open access)

Technology development for the design of shallow land burial facilities at semiarid sites

The following topics are discussed: effectiveness of a moisture barrier, physical basis for capillary barriers, trench cap designs for long-term stabilization, biointrusion barrier testing, and joint DOE/NRC tracer migration experiment. (LM)
Date: January 1, 1986
Creator: Abeele, W. V.; Nyhan, J. W. & Drennon, B. J.
Object Type: Article
System: The UNT Digital Library
Consolidation and shear failure leading to subsidence and settlement. Final report (open access)

Consolidation and shear failure leading to subsidence and settlement. Final report

Subsidence and settlement are phenomena that are much more destructive than generally thought. In shallow land burials they may lead to cracking of the overburden and eventual exposure and escape of waste material. The primary causes are consolidation and cave-ins. Laboratory studies performed at Los Alamos permit us to predict settlement caused by consolidation or natural compaction of the crushed tuff overburden. We have also investigated the shear failure characteristics of crushed tuff that may lead to subsidence. Examples of expected settlement and subsidence are calculated based on the known geotechnical characteristics of crushed tuff. The same thing is done for bentonite/tuff mixes because some field experiments were performed using this additive (bentonite) to reduce the hydraulic conductivity of the crushed tuff. Remedial actions, i.e., means to limit the amount of settlement, are discussed. We finally discuss our field experiment, which studies the influence of subsidence on layered systems in general and on biobarriers in particular. The share of the produced cavities is compared with cavities produced by idealized voids in an idealized environment. Study of root penetration at subsidence sites gives us an indication of the remaining degree of integrity. 30 refs., 24 figs., 19 tabs.
Date: February 1, 1986
Creator: Abeele, W.; Nyhan, J. W.; Hakonson, T. E.; Drennon, B. J.; Lopez, E. A.; Herrera, W. J. et al.
Object Type: Report
System: The UNT Digital Library
Low-level integrated system test (open access)

Low-level integrated system test

An unusually wet season permitted us to test the integrity of our biobarrier installed in the improved or modified plots in our integrated system. Although the modified plots had a reduced water-holding capacity, they delivered leachate only at the drain installed above the biobarrier, demonstrating once more that the biobarrier is behaving successfully as a capillary barrier in rerouting the subsurface flow around the tuff beneath the biobarrier. As a result of vertical water flow impedance, more water was made available to plot vegetation, enhancing its growth dramatically. The capillary barrier theory was backed up by the tensiometer results showing saturation at the upper biobarrier interface. 11 refs., 19 figs
Date: February 1, 1986
Creator: Abeele, Willy; Nyhan, John; Hakonson, Tom; Drennon, Barry J.; Lopez, Edward A.; Herrera, Wilfred J. et al.
Object Type: Report
System: The UNT Digital Library
Exchange of bonded hydrogen in amorphous silicon by deuterium (open access)

Exchange of bonded hydrogen in amorphous silicon by deuterium

We show that bonded hydrogen in a-Si:H is readily exchanged by atomic deuterium when exposed to a deuterium plasma discharge. The effective diffusion coefficient for the D,H exchange 10/sup -14/ cm/sup 2//sec at 160/sup 0/C, is comparable to that of interstitial hydrogen in c-Si.
Date: December 1, 1986
Creator: Abeles, B.; Yang, L.; Leta, D.P. & Majkrzak, C.F.
Object Type: Article
System: The UNT Digital Library
NMR investigations of aging effects in palladium tritide (open access)

NMR investigations of aging effects in palladium tritide

Using pulsed NMR techniques, relaxation times for triton, proton, and /sup 3/He nuclei in recently synthesized PdH/sub x/ and PdT/sub x/ samples were measured as a function of temperature in the range 100 less than or equal to T less than or equal to 300/sup 0/K. Rigid lattice second moments (T approx. = 100/sup 0/K) were also determined. These results provide baseline information for an extended study of aging effects of PdT/sub x/. 6 refs., 7 figs., 2 tabs.
Date: January 1, 1986
Creator: Abell, G.C. & Attalla, A.
Object Type: Article
System: The UNT Digital Library
Stress corrosion cracking tests on high-level-waste container materials in simulated tuff repository environments (open access)

Stress corrosion cracking tests on high-level-waste container materials in simulated tuff repository environments

Types 304L, 316L, and 321 austenitic stainless steel and Incoloy 825 are being considered as candidate container materials for emplacing high-level waste in a tuff repository. The stress corrosion cracking susceptibility of these materials under simulated tuff repository conditions was evaluated by using the notched C-ring method. The tests were conducted in boiling synthetic groundwater as well as in the steam/air phase above the boiling solutions. All specimens were in contact with crushed Topopah Spring tuff. The investigation showed that microcracks are frequently observed after testing as a result of stress corrosion cracking or intergranular attack. Results showing changes in water chemistry during test are also presented.
Date: June 1, 1986
Creator: Abraham, T.; Jain, H. & Soo, P.
Object Type: Report
System: The UNT Digital Library
User systems guidelines for software projects (open access)

User systems guidelines for software projects

This manual presents guidelines for software standards which were developed so that software project-development teams and management involved in approving the software could have a generalized view of all phases in the software production procedure and the steps involved in completing each phase. Guidelines are presented for six phases of software development: project definition, building a user interface, designing software, writing code, testing code, and preparing software documentation. The discussions for each phase include examples illustrating the recommended guidelines. 45 refs. (DWL)
Date: April 1, 1986
Creator: Abrahamson, L. (ed.)
Object Type: Report
System: The UNT Digital Library
Micelle-derived catalysts for extended Schulz-Flory (open access)

Micelle-derived catalysts for extended Schulz-Flory

The objective of this program is to develop a synthesis gas conversion catalyst with higher selectivity to liquid fuels, while maintaining catalytic activity and stability at least equivalent relative to state-of-the-art precipitated iron catalysts. Hydrocarbon cutoff hypothesis and developmental needs for a ruthenium catalyst with low light ends selectivity were investigated during this quarter. Hydrocarbon product distribution was Anderson-Schulz-Flory up to a carbon number of 250 and cutoff did not occur with a titania-supported catalyst containing ruthenium particles smaller than 20[Angstrom]. It was found that an alumina-supported catalyst with 1% (by weight) ruthenium in the form of 50[Angstrom] to 100[Angstrom] metal particles was initially about half as active (by catalyst volume) and made one quarter of the amount of C[sub 1][minus]C[sub 4] light end products relative to the Sasol precipitated iron catalyst.
Date: January 1, 1986
Creator: Abrevaya, H.
Object Type: Report
System: The UNT Digital Library
Micelle-derived catalysts for extended Schulz-Flory (open access)

Micelle-derived catalysts for extended Schulz-Flory

The objective of this program is to develop a synthesis gas conversion catalyst with higher selectivity to liquid fuels, while maintaining catalytic activity and stability at least equivalent relative to state-of-the-art precipitated iron catalysts. During this quarter, the emphasis in the program has been the investigation of the hydrocarbon cutoff hypothesis with supported ruthenium catalysts. An alumina-supported catalyst with smaller than 20[Angstrom] ruthenium particles was tested under conditions of maximal water gas shift activity. During this test more than 90% of the water made in the Fischer-Tropsch synthesis reaction was converted to H[sub 2]. However, the extent of ruthenium metal agglomeration was not reduced. Accordingly, it was not possible to conclude whether hydrocarbon cutoff occurs with smaller than 20[Angstrom] ruthenium particles on [gamma]-alumina. A ruthenium catalyst prepared on Y-type zeolite had 20[Angstrom] or smaller ruthenium particles according to STEM examination and a 15[Angstrom] average ruthenium metal particle size according to EXAFS examination. The ruthenium metal particle size was stable during the test with this catalyst. The hydrocarbon product distribution was Anderson-Schulz-Flory with no cutoff up to a carbon number of 160. A well-dispersed titania-supported ruthenium catalyst is going to be evaluated during the next quarter in order to determine whether …
Date: January 1, 1986
Creator: Abrevaya, H.
Object Type: Report
System: The UNT Digital Library
Micelle-derived catalysts for extended Schulz-Flory (open access)

Micelle-derived catalysts for extended Schulz-Flory

The objective of this program is to develop a synthesis gas conversion catalyst selective to gasoline or diesel range fuel via application of a micelle technique for preparing specific site supported ruthenium particles. The current emphasis is to investigate hydrocarbon cutoff principle and to apply it for developing selective catalysts. During this quarter, micelle technique was further improved and 1 ruthenium particle:l reverse micelle limit was approached by careful control of catalyst synthesis conditions. Accordingly, it became possible to synthesize supported particles that closely meet the size and composition targets originally set. This improved technique was applied to synthesis of chemically modified ruthenium catalysts. Some of the chemically modified ruthenium catalysts will be evaluated later in the program. We previously reported that 40--60 [Angstrom] ruthenium particles prepared on [gamma]-alumina do not result in hydrocarbon cutoff. We could not determine then whether smaller ruthenium particles result in hydrocarbon cutoff because these particles agglomerated via ruthenium carbonyl formation during the course of a 6--10 day test. We have recently evaluated a catalyst with 20--40 [Angstrom] ruthenium particles prepared on [gamma]-alumina by carefully analyzing products initially made during the test prior to substantial ruthenium agglomeration. We concluded that cutoff is not effected by …
Date: January 1, 1986
Creator: Abrevaya, H.
Object Type: Report
System: The UNT Digital Library
Micelle-derived catalysts for extended Schulz-Flory (open access)

Micelle-derived catalysts for extended Schulz-Flory

The objective of this program is to develop a synthesis gas conversion catalyst with improved selectivity to gasoline or diesel range fuel via application of a micelle technique for preparing novel supported catalysts with specific size ruthenium particles. The major emphasis is to investigate hydrocarbon cutoff principle and to apply it for developing selective catalysts. We previously reported that cutoff is not effected with 40--60 [Angstrom] and 20--40 [Angstrom] ruthenium particles on [gamma]-Al[sub 2]O[sub 3]. We recently tested a catalyst with <20 [Angstrom] ruthenium particles. Well dispersed ruthenium in that catalyst extensively agglomerated to larger particles even during the course of a short test despite the high H[sub 2]:CO ratio used. Therefore, we could not conclude whether cutoff is effected with <20 [Angstrom] ruthenium particles. We are going to continue to evaluate the effect of operational conditions and also evaluate the effect of modifiers on ruthenium agglomeration. A catalyst with <20 [Angstrom] ruthenium particles will be evaluated to investigate occurrence of cutoff, after no agglomeration conditions are identified. We are now proposing to conduct, parallel to the main approach, a second research approach which will aim at developing a ruthenium catalyst with substantially lower light ends selectivity while maintaining at …
Date: January 1, 1986
Creator: Abrevaya, H.
Object Type: Report
System: The UNT Digital Library