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Physics at hadron colliders: Experimental view (open access)

Physics at hadron colliders: Experimental view

The physics of the hadron-hadron collider experiment is considered from an experimental point of view. The problems encountered in determination of how well the standard model describes collider results are discussed. 53 refs., 58 figs.
Date: August 1, 1987
Creator: Siegrist, J.L.
Object Type: Article
System: The UNT Digital Library
Transverse energy distributions in Si + nucleus collisions at 10 GeV/nucleon (open access)

Transverse energy distributions in Si + nucleus collisions at 10 GeV/nucleon

Transverse energy distributions have been measured for collisions of 10 GeVnucleon Si with targets of Al, Cu and Pb using a combination of a NaI wall and a uranium based sampling calorimeter. The measured cross sections d..sigma..dE/sub T/ and dE/sub T/d)eta are consistent with full stopping and an increase, with increasing values of E/sub T/, of energy flow into large angles. 4 refs., 7 figs., 2 tabs
Date: August 1, 1987
Creator: Bassalleck, B; Braun-Munzinger, P.; Cleland, W.; G., David; Farooq, A.; Fatyga, M. et al.
Object Type: Article
System: The UNT Digital Library
Development of highly polished, grazing incidence mirrors for synchrotron radiation beam lines at SSRL (open access)

Development of highly polished, grazing incidence mirrors for synchrotron radiation beam lines at SSRL

New platinum-coated grazing incidence mirrors with low surface roughnesses have been developed to focus bending magnet radiation from the SSRL/SLAC SPEAR storage ring on the entrance slits of two Beam Line VIII grating monochromators. The first mirror in the toroidal grating monochromator (TGM) branch is a cooled SiC cylinder capable of absorbing synchrotron radiation power levels of up to 260 watts without excessive distortion. This mirror deflects the beam vertically through a 12/degree/ angle and focuses it sagitally on the TGM entrance slit plane. The second TGM optical element is a fused-silica spherical mirror with a large radius of curvature that deflects the beam vertically through an additional 12/degree/ and focuses it tangentially with 3/1 demagnification. The first mirror in our spherical grating branch is a 5/degree/-vertically deflecting, cooled SiC toroid designed to focus tangentially on the monochromator entrance slits and sagitally in the exit slits. A 4/degree/-deflecting fused silica mirror is used after the exit sites in each beam line to refocus on to the sample. For this application a thin cylinder is bent to approximate an ellipsoid. The mirrors are now installed at SSRL and performance measurements are planned. Qualitatively the focus of the TGM optics at the …
Date: August 1, 1987
Creator: Tirsell, K. G.; Berglin, E. J.; Fuchs, B. A.; Holdener, F. R.; Humpal, H. H.; Karpenko, V. P. et al.
Object Type: Article
System: The UNT Digital Library
Similarity solutions of nonlinear partial differential equations invariant to a family of affine groups (open access)

Similarity solutions of nonlinear partial differential equations invariant to a family of affine groups

Problems of technological interest can very often be described by partial differential equations (PDEs) with one dependent and two independent variables (call them c, z, and t, respectively). Many such PDEs are invariant to one-parameter families of one-parameter affine groups. Similarity solutions are solutions of the PDE that are invariant to one group of the family. The great utility of similarity solutions is that they may be calculated by solving an ODE rather than a PDE and are thus much more easily accessible than other solutions. The form of the principal ODE depends, of course, on the form of the PDE, but it can be proved quite generally that the principal ODE is itself invarient to the one-parameter affine group or associated group. because of the invariance of the principal ODE to the associated group, the dependence on the boundary and initial conditions of certain special values of the function y(x), e.g., y(O), y(infinity), y(O), ets., may be predicted a priori without solving the principal ODE. The nonlinear PDE of heat transport in superfluid He-II, is used as an illustration of these ideas in this review.
Date: August 1, 1987
Creator: Dresner, L.
Object Type: Article
System: The UNT Digital Library
Gasification of char in a membrane filter: Final report (open access)

Gasification of char in a membrane filter: Final report

This report deals with the feasibility of reducing the amount of char on a barrier filter by in-place gasification. Compared to the very rapid pyrolysis step, the gasification of char on a filter requires substantial time under conditions that favor the gasification reactions. Three categories of information were of greatest interest: (1) The origin, characteristics and properties of the char. (2) The conditions under which the char was gasified and the rates and extents of the gasification reactions. (3) Any interpretation or mathematical modelling of the experimental results. 74 refs., 10 tabs.
Date: August 1, 1987
Creator: Hess, M. & Di Bella, C.A.W.
Object Type: Report
System: The UNT Digital Library
Conceptual design of a black liquor gasification pilot plant (open access)

Conceptual design of a black liquor gasification pilot plant

In July 1985, Champion International completed a study of kraft black liquor gasification and use of the product gases in a combined cycle cogeneration system based on gas turbines. That study indicated that gasification had high potential as an alternative to recovery boiler technology and offered many advantages. This paper describes the design of the plant, the construction of the pilot plant, and finally presents data from operation of the plant.
Date: August 1, 1987
Creator: Kelleher, E. G.
Object Type: Report
System: The UNT Digital Library
Ultrasonic beam distortion in transversely isotropic media (open access)

Ultrasonic beam distortion in transversely isotropic media

The distortion of beam profiles and skewing of beam energy observed in transmission of ultrasound into a transversely isotropic medium can lead to erroneous interpretations of NDE data for materials such as columnar-grain steels and fiber-reinforced composites. In this paper, results are presentd for the numerical evaluation of the exact Fourier integral representation of transmission of an arbitrary incident field from an isotropic into a transversely isotropic half-space. The problem is fully three-dimensional, i.e., the symmetry axis of the transversely isotropic material is oriented arbitrarily relative to the half-space boundary and angles of incidence. The cases chosen for numerical study were selected from previously unexplained experimental data obtained from the study of propagation in columnar grain steels (welds), and from situations commonly encountered during the inspection of fiber-reinforced composites. Experimental results which give evidence to the numerically observed phenomena are presented. 11 refs., 4 figs.
Date: August 1, 1987
Creator: Roberts, R. A. & Kupperman, D. S.
Object Type: Article
System: The UNT Digital Library
Comparative studies in direct slow-neutron capture calculations (open access)

Comparative studies in direct slow-neutron capture calculations

Primary E1 transitions due to thermal neutron capture by the nuclides /sup 9/Be, /sup 32,34/S, /sup 40,42,44,46,48/Ca, and /sup 58/Ni are quantitatively interpreted by the Lane-Lynn formula and are compared with recent optical model calculations. The two approaches are equivalent provided the internal region of the nucleus is excluded in the optical model approach. Theoretical justifications for such a procedure are briefly presented. 32 refs., 4 tabs.
Date: August 1, 1987
Creator: Mughabghab, S. F.
Object Type: Article
System: The UNT Digital Library
Corrosion behavior of vanadium alloys in flowing lithium (open access)

Corrosion behavior of vanadium alloys in flowing lithium

Corrosion data are presented for several vanadium alloys exposed to flowing lithium at 427, 482, and 538/sup 0/C. The corrosion behavior is evaluated by weight change measurements. Metallographic results and data on the nonmetallic element transfer in lithium-exposed specimens are also presented. The influence of alloy composition and exposure conditions on the corrosion behavior of vanadium alloys is discussed. 6 refs., 9 figs., 2 tabs.
Date: August 1, 1987
Creator: Chopra, O. K. & Smith, D. L.
Object Type: Article
System: The UNT Digital Library
An overview of environmental degradation of materials in nuclear power plant piping systems (open access)

An overview of environmental degradation of materials in nuclear power plant piping systems

Piping in light water reactor (LWR) power systems is affected by several types of environmental degradation: intergranular stress corrosion cracking (IGSCC) of austenitic stainless steel piping in boiling water reactors (BWRs) has required research, inspection, and mitigation programs that will ultimately cost several billion dollars; erosion-corrosion of carbon steel piping has been observed frequently in the secondary systems of both BWRs and pressurized water reactors (PWRs); the effect of the BWR environment can greatly diminish the design margin inherent in the ASME Section III fatigue design curves for carbon steel piping; and cast stainless steels are subject to embrittlement after extended thermal aging at reactor operating temperatures. These problems are being addressed by wide-ranging research programs in this country and abroad. The purpose of this review is to highlight some of the accomplishments of these programs and to note some of the remaining unanswered questions.
Date: August 1, 1987
Creator: Shack, W.J.
Object Type: Article
System: The UNT Digital Library
Environmentally assisted cracking in light water reactors (open access)

Environmentally assisted cracking in light water reactors

Cracking in sensitized austenitic stainless steel (SS) piping and associated components in boiling water reactors (BWRs) has been observed since the mid-1960s. Proposed remedies include procedures that produce a favorable residual stress state in the weld regions, replacement of the piping with materials that are more resistant to SCC, and modification of the reactor coolant environment. During this year, studies that have important implications for all three classes of proposed remedies have been carried out. These studies include fracture-mechanics crack-growth-rate tests on Type 316 NG SS and weld overlay specimens in impurity and high-purity environments, finite-element studies on weldments treated by the Mechanical Stress Improvement Process (MSIP) developed by O'Donnell and Associates, heat-to-heat studies of SCC in alternate alloys such as Types 316 NG and 347 Mod SS, and slow-strain-rate tests for the characterization of a variety of potential reactor coolant impurities. In addition, studies on the corrosion potential of irradiated stainless steel have been performed. This work is intended to provide a better understanding of the conditions associated with irradiation-assisted SCC (IASCC) in the core region.
Date: August 1, 1987
Creator: Shack, W. J.; Kassner, T. F.; Maiya, P. S.; Park, J. Y.; Ruther, W. E.; Kuczay, T. M. et al.
Object Type: Article
System: The UNT Digital Library
Use of a United States mid-Pacific Island territory for a Pacific Island Repository System (PIRS): Extended summary (open access)

Use of a United States mid-Pacific Island territory for a Pacific Island Repository System (PIRS): Extended summary

The concept of using a mid-ocean island for a geologic high-level waste repository was investigated. The technical advantages include geographical isolation and near-infinite ocean dilution as a backup to repository geological waste isolation. The institutional advantages are reduced siting problems and the potential of creating an international waste repository. Establishment of international waste repository would allow cost sharing, aid US nonproliferation goals, and assure proper disposal of spent fuel from developing countries. The major uncertainties in this concept are rock conditions at waste disposal depths and costs. 13 refs., 2 tabs.
Date: August 1, 1987
Creator: Forsberg, Charles W.
Object Type: Article
System: The UNT Digital Library
Process monitoring in support of International Atomic Energy Agency safeguards (open access)

Process monitoring in support of International Atomic Energy Agency safeguards

A review of previous efforts in process monitoring for safeguards was conducted. Previous efforts touched on various concepts and a few specific applications, but none was comprehensive in addressing all aspects of a process monitoring application for safeguards. This report develops prototypical process monitoring concepts that can be incorporated into the International Atomic Energy Agency's (IAEA's) general safeguards approach for fuel reprocessing plants. This effort considers existing approaches, recognizing limitations and needed improvements. Prototypical process monitoring applications are developed and proposed for implementation and demonstration in the Integrated Equipment Test facility, which is located at the Oak Ridge National Laboratory. The specific information needed to accomplish the process monitoring objectives are defined, and the mechanics for obtaining that information are described. Effort is given to the identification and assessment of potential impacts and benefits associated with process monitoring concepts, with particular attention to IAEA, state, and plant operator interests. The historical development of process monitoring is described and the implications of using process monitoring in international safeguards are discussed. Specific process process monitoring applications for demonstration in the IET facility are developed in Sects. 6 through 14. 1 fig.
Date: August 1, 1987
Creator: Ehinger, M. H.; Wachter, J. W.; Hebble, T. L. & Kerr, H. T.
Object Type: Report
System: The UNT Digital Library

[Photograph 2012.201.B0268.0085]

Photograph used for a newspaper owned by the Oklahoma Publishing Company. Caption: "Capt. Norman Howell, who already owns one world record set in his Ugly Quicking, will seek an international speed mark today during Mid-America Summerfest in Enid."
Date: August 1, 1987
Creator: unknown
Object Type: Photograph
System: The Gateway to Oklahoma History

[Photograph 2012.201.B0106.0051]

Photograph used for a newspaper owned by the Oklahoma Publishing Company. Caption: "The four lanes of this tall bridge over the railroad tracks on Martin Luther King Avenue between Reno and NE 4th will open in March."
Date: August 1, 1987
Creator: Hoke, Doug
Object Type: Photograph
System: The Gateway to Oklahoma History
Liquid Fuels from Microalgae (open access)

Liquid Fuels from Microalgae

The goal of the DOE/SERI Aquatic Species Program is to develop the technology to produce gasoline and diesel fuels from microalgae. Microalgae can accumulate large quantities of lipids and can thrive in high salinity water, which currently has no other use.
Date: August 1, 1987
Creator: Johnson, D. A. & Sprague, S.
Object Type: Report
System: The UNT Digital Library
The charge state of iron implanted into sapphire (open access)

The charge state of iron implanted into sapphire

Several techniques (RBS, TEM, CEMS) have been used to characterize sapphire single crystals implanted with iron at room temperature to fluences of 10/sup 16/ to 10/sup 17/ ions cm/sup -2/. At low fluences the as-implanted iron is found mainly in the ferrous state. As the fluence is increased, Fe/sup 3 +/ and metallic iron clusters became dominant. There is a strong correlation between the probability of finding specific configurations of iron ions within four cation coordination shells and the relative amounts of each charge state observed. The superparamagnetic behavior of the clusters suggest that they are of the order of 2 nm in size but the large amount of irradiation-induced damage and residual stress has prevented their imaging by TEM. 13 refs., 7 figs.
Date: August 1, 1987
Creator: McHargue, C. J.; Sklad, P. S.; White, C. W.; Farlow, G. C.; Perez, A.; Kornilios, N. et al.
Object Type: Article
System: The UNT Digital Library
Review of international geothermal activities and assessment of US industry opportunities: Summary report (open access)

Review of international geothermal activities and assessment of US industry opportunities: Summary report

This report summarizes a study initiated to review and assess international developments in the geothermal energy field and to define business opportunities for the US geothermal industry. The report establishes data bases on the status of worldwide geothermal development and the competitiveness of US industry. Other factors identified include existing legislation, tax incentives, and government institutions or agencies and private sector organizations that promote geothermal exports. Based on the initial search of 177 countries and geographic entities, 71 countries and areas were selected as the most likely targets for the expansion of the geothermal industry internationally. The study then determined to what extent their geothermal resource had been developed, what countries had aided or participated in this development, and what plans existed for future development. Data on the energy, economic, and financial situations were gathered.
Date: August 1, 1987
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Experimental Studies of Electromagnetic Properties of Few Body Systems (open access)

Experimental Studies of Electromagnetic Properties of Few Body Systems

An overview is given of some recent and planned experiments which have or will substantially increase our knowledge of the electromagnetic properties of few body systems. Specific examples include the proton and neutron elastic form factors, the deuteron elastic form factors, deuteron threshold electrodisintegration and quasi-elastic scattering, deuteron photodisintegration, and finally measurements of cross sections in deep inelastic scattering from hydrogen, deuterium, and iron. 47 refs., 13 figs. (DWL)
Date: August 1, 1987
Creator: Bosted, P. E.
Object Type: Article
System: The UNT Digital Library
Estimating payload internal temperatures and radiator size for multimegawatt space platforms (open access)

Estimating payload internal temperatures and radiator size for multimegawatt space platforms

A conceptual space platform consists of a payload, a power conditioning unit (PCU), and two radiators: the main radiator and a secondary radiator. A computer program was written to determine the required size of the two radiators and the temperatures of the PCU and payload for a given platform power level. An iterative approach is necessary because the required size of the main radiator depends on the size of the secondary radiator and vice versa. Also, the temperatures of the payload and PCU depend on the size of the radiators. The program user can subdivide the two radiators into any number of nodes to increase the accuracy of the radiant heat transfer solution. The use of more nodes also allows better prediction of the nonlinear temperature drop that occurs across the radiators as the working fluid deposits the platform's waste heat in the radiator. View factor expressions are automatically calculated for different choices of the number of nodes. The user can also select different separation distances between the various platform structures. A model is included to couple the radiant and conduction heat transfer that occurs between the payload and its meteoroid shell and between the PCU and its shell. Also, …
Date: August 1, 1987
Creator: Dobranich, D.
Object Type: Report
System: The UNT Digital Library
System studies of compact ignition tokamaks (open access)

System studies of compact ignition tokamaks

The new Tokamak Systems Code, used to investigate Compact Ignition Tokamaks (CITs), can simultaneously vary many parameters, satisfy many constraints, and minimize or maximize a figure of merit. It is useful in comparing different CIT design configurations over wide regions of parameter space and determining a desired design point for more detailed physics and engineering analysis, as well as for performing sensitivity studies for physics or engineering issues. Operational windows in major radius (R) and toroidal field (B) space for fixed ignition margin are calculated for the Ignifed and Inconel candidate CITs. The minimum R bounds are predominantly physics limited, and the maximum R portions of the windows are engineering limited. For a modified Kaye-Goldston plasma-energy-confinement scaling, the minimum size is 1.15 m for the Ignifed device and 1.25 m for the Inconel device. With the Ignition Technical Oversight Committee (ITOC) physics guidance of B/sup 2/a/q and I/sub p/ >10 MA, the Ignifed and Base-line Inconel devices have a minimum size of 1.2 and 1.25 m and a toroidal field of 11 and 10.4 T, respectively. Sensitivity studies show Ignifed to be more sensitive to coil temperature changes than the Inconel device, whereas the Inconel device is more sensitive to …
Date: August 1, 1987
Creator: Galambos, J. D.; Blackfield, D. T.; Peng, Y. K. M.; Reid, R. L.; Strickler, D. J. & Selcow, E.
Object Type: Report
System: The UNT Digital Library
Component Fragility Research Program: Phase 1, Demonstration tests: Volume 1, Summary report (open access)

Component Fragility Research Program: Phase 1, Demonstration tests: Volume 1, Summary report

This report describes tests performed in Phase I of the NRC Component Fragility Research Program. The purpose of these tests was to demonstrate procedures for characterizing the seismic fragility of a selected component, investigating how various parameters affect fragility, and finally using test data to develop practical fragility descriptions suitable for application in probabilistic risk assessments. A three-column motor control center housing motor controllers of various types and sizes as well as relays of different types and manufacturers was subjected to seismic input motions up to 2.5g zero period acceleration. To investigate the effect of base flexibility on the structural behavior of the MCC and on the functional behavior of the electrical devices, multiple tests were performed on each of four mounting configurations: four bolts per column with top bracking, four bolts per column with no top brace, four bolts per column with internal diagonal bracking, and two bolts per column with no top or internal bracking. Device fragility was characterized by contact chatter correlated to local in-cabinet response at the device location. Seismic capacities were developed for each device on the basis of local input motion required to cause chatter; these results were then applied to develop probabilistic fragility …
Date: August 1, 1987
Creator: Holman, G. S.; Chou, C. K.; Shipway, G. D. & Glozman, V.
Object Type: Report
System: The UNT Digital Library
The role of pre-equilibrium theory in nuclear data evaluation (open access)

The role of pre-equilibrium theory in nuclear data evaluation

We illustrate the utility of preequilibrium plus equilibrium decay models in reproducing neutron and ..gamma..-ray spectra for incident nucleons of approx. = 2 to 20 MeV. We discuss models and theories for calculating preequilibrium nucleon angular distributions and the short comings involved. Attention is focussed on special problems in modelling preequliibrium reactions for target nuclei near shell closures, and possible ways to improve the modelling in these regimes by use of shell model levels to generate few quasi-particle state densities. We show preliminary tests of applicability of preequilibrium models to incident nucleon energies up to 1 GeV and for heavy ion induced reactions at energies up to 300 MeV, areas where modern technology is increasingly seeking nuclear data input. 40 refs., 16 figs.
Date: August 1, 1987
Creator: Blann, M.
Object Type: Article
System: The UNT Digital Library
Fully developed turbulence via Feigenbaum's period-doubling bifurcations (open access)

Fully developed turbulence via Feigenbaum's period-doubling bifurcations

Since its publication in 1978, Feigenbaum's predictions of the onset of turbulence via period-doubling bifurcations have been thoroughly borne out experimentally. In this paper, Feigenbaum's theory is extended into the regime in which we expect to see fully developed turbulence. We develop a method of averaging that imposes correlations in the fluctuating system generated by this map. With this averaging method, the field variable is obtained by coarse-graining, while microscopic fluctuations are preserved in all averaging scales. Fully developed turbulence will be shown to be a result of microscopic fluctuations with proper averaging. Furthermore, this model preserves Feigenbaum's results on the physics of bifurcations at the onset of turbulence while yielding additional physics both at the onset of turbulence and in the fully developed turbulence regime.
Date: August 1, 1987
Creator: Duong-van, M.
Object Type: Article
System: The UNT Digital Library