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ANHARMONIC POTENTIAL CONSTANTS AND THEIR DEPENDENCE UPON BOND LENGTH (open access)

ANHARMONIC POTENTIAL CONSTANTS AND THEIR DEPENDENCE UPON BOND LENGTH

Empirical study of cubic and quartic vibrational force constants for diatomic molecules shows them to be approximately exponential functions of internuclear distance. A family of curves is obtained, determined by the location of the bonded atoms in rows of the periodic table. Displacements between successive curves correspond closely to those in Badger's rule for quadratic force constants (for which the parameters are redetermined to accord with all data now available). Constants for excited electronic and ionic states appear on practically the same curves as those for the ground states. Predictions based on the diatomic correlations agree with the available cubic constants for bond stretching in polyatomic molecules, regardless of the type of bonding involved. Implications of these regularities are discussed. (auth)
Date: August 1, 1961
Creator: Herschbach, D.R. & Laurie, V.W.
System: The UNT Digital Library
Proceedings of the LAMPF workshop on physics with polarized nuclear targets (open access)

Proceedings of the LAMPF workshop on physics with polarized nuclear targets

Topics of discussion included static and dynamic methods for polarizing nuclei, proton and pion nucleus scattering experiments, and possible future experiments at LAMPF. Separate abstracts were prepared for 11 papers in this report. (DWL)
Date: August 1, 1986
Creator: Burleson, G.; Gibbs, W.; Hoffmann, G.; Jarmer, J. J. & Tanaka, N. (eds.)
System: The UNT Digital Library
Comments on septa and other small production angle magnets (open access)

Comments on septa and other small production angle magnets

A discussion is given of possible septum magnet parameters for small production angle experiments in the ISABELLE storage rings. Superconducting septa and torroidal septa are also considered. (PMA)
Date: August 25, 1977
Creator: Allinger, J.; Danby, G. & Jackson, J.
System: The UNT Digital Library
Effects of light intensity and PH on photosynthesis in Elodea densa (open access)

Effects of light intensity and PH on photosynthesis in Elodea densa

None
Date: August 1, 1975
Creator: Weber, J.A. & Gates, D.M.
System: The UNT Digital Library
Heavy mass states (open access)

Heavy mass states

The indirect evidence for the production of a heavy lepton and direct evidence for the product of a new hadronic state or states in proton-proton interactions is considered for the interpretation requiring the existence of two more leptons and two new quarks. It is shown that such a picture is consistent and in good agreement with existing data. The new structure is located at M = 9.54 GeV/c/sup 2/ and is much wider than the experimental resolution. Also it is asymmetric, suggesting the presence of several resonances. 7 references. (JFP)
Date: August 23, 1977
Creator: Paschos, E. A.
System: The UNT Digital Library
Adaptive Mesh Refinement for 1-Dimensional Gas Dynamics (open access)

Adaptive Mesh Refinement for 1-Dimensional Gas Dynamics

We consider the solution of the one-dimensional equation of gas-dynamics. Accurate numerical solutions are difficult to obtain on a given spatial mesh because of the existence of physical regions where components of the exact solution are either discontinuous or have large gradient changes. Numerical methods treat these phenomena in a variety of ways. In this paper, the method of adaptive mesh refinement is used. A thorough description of this method for general hyperbolic systems is given elsewhere and only properties of the method pertinent to the system are elaborated.
Date: 1982-08~
Creator: Hedstrom, Gerald; Rodrigue, Garry; Berger, Marsha & Oliger, Joseph
System: The UNT Digital Library
Some recent developments in nuclear charged particle detectors (open access)

Some recent developments in nuclear charged particle detectors

The latest developments of large-area, position sensitive gas-filled ionization chambers are described. Multi-wire-proportional chambers as position-sensing and parallel-plate-avalanche counters as time-sensing detectors at low pressure (5 torr) have proven to be useful and reliable instruments in heavy ion physics. Gas (proportional) scintillation counters, used mainly for x-ray spectroscopy, have recently been applied as particle detectors. Finally, a brief description of a large plastic scintillator spectrometer, the Plastic Ball, is given and some of the first test and calibration data are shown.
Date: August 1, 1980
Creator: Stelzer, H.
System: The UNT Digital Library
Progress report on the development of the General Atomic thermochemical water-splitting process (open access)

Progress report on the development of the General Atomic thermochemical water-splitting process

The major accomplishments of the DOE funded part of the GA thermochemical water-splitting program are reported. They include: completion of installation of all bench-scale equipment; operation and preliminary data acquisition for bench-scale subunits I and II; design, installation and operation of a system for iodine removal from the low phase; review and modification of Section III of the engineering flowsheet resulting in an increase in process efficiency and decrease in capital cost; and completion of the Funk panel reivew. The results of the experimental work have demonstrated that flowsheet conditions can be achieved in all cases tested. Continued work on the flowsheet has increased our confidence in the economic viability of the sulfur-iodine process.
Date: August 1, 1980
Creator: Besenbruch, G.E.; Allen, C.L.; Brown, L.C.; McCorkle, K.; Rode, J.S.; Norman, J.H. et al.
System: The UNT Digital Library
The U5. 0 undulator design for the advanced light source at LBL (open access)

The U5. 0 undulator design for the advanced light source at LBL

The U5.0 undulator, currently under design, is the first in a series of insertion devices planned for the Advanced Light Source at LBL. U5.0 parameters include a 5 cm period, 5 m length with a 0.837 T maximum field at a 14 mm gap. A hybrid configuration utilizing Nd-Fe-B permanent magnet material and Vanadium Permendur poles is used for the magnetic structure. Construction is modular with many pole assemblies attached to a pole mount, which in turn is fastened onto one of the backing beams. Vertical field integral correction at the ends is with permanent magnet rotators. The supports structure features a 4-post configuration, a rigid base with 3 kinematic floor supports and 2 rigid 5 m long backing beams that fit within the 2.4 m high accelerator enclosure. The drive system is computer controlled utilizing a stepper motor and shaft encode coupled to a roller-screw/nut and chain drive train. Vacuum chamber design is a rigid configuration with a 10 mm vertical by 218 mm horizontal aperture of 5.5 m length. Chamber fabrication features a two-piece welded chamber of 5083 H321 aluminum. Pumping is with ion and titanium sublimation pumps. 5 figs., 1 tab.
Date: August 1, 1989
Creator: Hoyer, E.; Chin, J.; Halbach, K.; Hassenzahl, W.; Humphries, D.; Kincaid, B. et al.
System: The UNT Digital Library
Methods of driving current by heating a toroidal plasma (open access)

Methods of driving current by heating a toroidal plasma

In addition to the usual mechanism which utilizes the Ohmic transformer current, which is necessarily pulsed, there exist several steady-state mechanisms. Heating mechanisms which can lend themselves efficiently to continuous current generation include neutral beams, Alfven waves, ion-cyclotron waves, lower-hybrid waves and electron-cyclotron waves.
Date: August 1, 1980
Creator: Fisch, N. J.
System: The UNT Digital Library
Construction and testing of the Mirror Fusion Test Facility magnets (open access)

Construction and testing of the Mirror Fusion Test Facility magnets

This paper describes the construction and testing of the Mirror Fusion Test Facility superconducting magnet set. Construction of the first Yin Yang magnet was started in 1978. And although this particular magnet was later modified, the final construction of these magnets was not completed until 1985. When completed these 42 magnets weighed over 1200 tonnes and had a maximum stored energy of approximately 1200 MJ at full field. Together with power supplies, controls and liquid nitrogen radiation shields the cost of the fabrication of this system was over $100M. General Dynamics/Convair Division was responsible for the system design and the fabrication of 20 of the magnets. This contract was the largest single procurement action at the Lawrence Livermore National Laboratory. During the PACE acceptance tests, the 26 major magnets were operated at full field for more than 24 hours while other MFTF subsystems were tested. From all of the data, the magnets operated to the performance specifications. For physics operation in the future, additional helium and nitrogen leak checking and repair will be necessary. In this report we will discuss the operation and testing of the MFTF Magnet System, the world's largest superconducting magnet set built to date. The topics …
Date: August 1, 1986
Creator: Kozman, T.; Shimer, D.; VanSant, J. & Zbasnik, J.
System: The UNT Digital Library
Physics of antimatter-matter reactions for interstellar propulsion (open access)

Physics of antimatter-matter reactions for interstellar propulsion

At the stage of the antiproton-nucleon annihilation chain of events relevant to propulsion the annihilation produces energetic charged pions and gamma rays. If annihilation occurs in a complex nucleus, protons, neutrons, and other nuclear fragments are also produced. The charge, number, and energy of the annihilation products are such that annihilation rocket engine concepts involving relatively low specific impulse (I/sub sp/ approx. = 1000 to 2000 s) and very high I/sub sp/ (3 x 10/sup 7/ s) appear feasible and have efficiencies on the order of 50% for annihilation energy to propulsion energy conversion. At I/sub sp/'s of around 15,000 s, however, it may be that only the kinetic energy of the charged nuclear fragments can be utilized for propulsion in engines of ordinary size. An estimate of this kinetic energy was made from known pieces of experimental and theoretical information. Its value is about 10% of the annihilation energy. Control over the mean penetration depth of protons into matter prior to annihilation is necessary so that annihilation occurs in the proper region within the engine. Control is possible by varying the antiproton kinetic energy to obtain a suitable annihilation cross section. The annihilation cross section at low energies is …
Date: August 22, 1986
Creator: Morgan, D.L. Jr.
System: The UNT Digital Library
HTGR safety philosophy (open access)

HTGR safety philosophy

The accident at the Three Mile Island has focused public attention on reactor safety. Many public figures advocate a safer method of generating nuclear electricity for the second nuclear era in the US. The paper discusses the safety philosophy of a concept deemed suitable for this second nuclear era. The HTGR, in the course of its evolution, included safety as a significant determinant in design philosophy. This is particularly evident in the design features which provide inherent safety. Inherent features cause releases from a wide spectrum of accident conditions to be low. Engineered features supplement inherent features. The significance of HTGR safety features is quantified and order-of-magnitude type of comparisons are made with alternative ways of generating electricity.
Date: August 1, 1980
Creator: Joskimovic, V. & Fisher, C.R.
System: The UNT Digital Library
Thermodynamics of natural and industrial waters (open access)

Thermodynamics of natural and industrial waters

The most effective general formulations of thermodynamic equations for multicomponent aqueous solutions are discussed with respect to various ranges of temperature, pressure and composition with emphasis on solutes important in natural or industrial waters. A familiar equation in molality and in excess Gibbs energy is very successful up to 300{degree}C and ionic strength 6 mol{center dot}kg{sup {minus}1}, and can often be extended to 350{degree}C or above at high pressure and in favorable cases to ionic strength 12 or even 20. Alternate methods valid to higher solute compositions, even to pure fused salts, are described. A more difficult situation arises near the critical point of water where the compressibility becomes infinite and a Helmholtz energy basis must be adopted. Existing equations for this range and still higher temperatures and pressures are considered and possible improvements discussed. 85 refs., 13 figs., 3 tabs.
Date: August 1, 1991
Creator: Pitzer, K.S.
System: The UNT Digital Library
Nuclear alkali metal Rankine power systems for space applications (open access)

Nuclear alkali metal Rankine power systems for space applications

Nucler power systems utilizing alkali metal Rankine power conversion cycles offer the potential for high efficiency, lightweight space power plants. Conceptual design studies are being carried out for both direct and indirect cycle systems for steady state space power applications. A computational model has been developed for calculating the performance, size, and weight of these systems over a wide range of design parameters. The model is described briefly and results from parametric design studies, with descriptions of typical point designs, are presented in this paper.
Date: August 1, 1986
Creator: Moyers, J. C. & Holcomb, R. S.
System: The UNT Digital Library
Ab initio calculations on collisions of low energy electrons with polyatomic molecules (open access)

Ab initio calculations on collisions of low energy electrons with polyatomic molecules

The Kohn variational method is one of simplest, and oldest, techniques for performing scattering calculations. Nevertheless, a number of formal problems, as well as practical difficulties associated with the computation of certain required matrix elements, delayed its application to electron--molecule scattering problems for many years. This paper will describe the recent theoretical and computational developments that have made the complex'' Kohn variational method a practical tool for carrying out calculations of low energy electron--molecule scattering. Recent calculations on a number of target molecules will also be summarized. 41 refs., 7 figs.
Date: August 1, 1991
Creator: Rescigno, T. N.
System: The UNT Digital Library
Structural analysis of the central Columbia Plateau utilizing radar, digital topography, and magnetic data bases (open access)

Structural analysis of the central Columbia Plateau utilizing radar, digital topography, and magnetic data bases

Interest in the Hanford site (Washington) as a nuclear production, power, and waste disposal site has led to generation of a vast quantity of geophysical and remote sensing data sets of the central Columbia Plateau. To data, these various studies, including at least 13 independent magnetic linear and image lineament studies, have not been adequately correlated. Therefore, these studies provide a unique opportunity to compare and contrast the viability of the different geophysical and remote sensing techniques. The geology of the central Columbia Plateau is characterized by subdued topography and limited outcrop, with most of the exposure concentrated in localized folded/faulted mountains (the Yakima folds) and along river canyons. In order to efficiently compare lineament data bases, we have written an automated computer routine that correlated lineaments that are within a user specified distance of each other. The angle between their trends has to be less than an input maximum separation angle. If more than two lineament maps exist for the area, the analyst may also specify the minimum number of times each structure must be seen. The lineament correlation routine was applied to data bases of all aeromagnetic linears as well as lineaments seen on radar and a digital …
Date: August 1, 1991
Creator: Thiessen, R. L.; Eliason, J. R.; Johnson, L. K.; Brougher, C. W. (Washington State Univ., Pullman, WA (United States). Dept. of Geology); Foley, M. G. & Beaver, D. E. (Pacific Northwest Lab., Richland, WA (United States))
System: The UNT Digital Library
Environmental recordkeeping: The administrative record (open access)

Environmental recordkeeping: The administrative record

This document provides information on an environmental records management system. It includes information on environmental recordkeeping; environmental regulations with emphasis on the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA); and the administrative record including a case study of the Hanford Site's administrative record system. This paper will focus on the following objectives: (1) Identify resources that can be used as reference tools; (2) understand the reasons for developing and maintaining an administrative record; and, (3) evaluate an existing system and identify means of complying with the regulations. 15 refs., 2 figs.
Date: August 1, 1991
Creator: Sprouse, B.S.
System: The UNT Digital Library
Jet rates from deep inelastic muon scattering in the W range of 15 to 35 GeV (open access)

Jet rates from deep inelastic muon scattering in the W range of 15 to 35 GeV

Production rates of forward jets in deep inelastic muon scattering are studied using the JADE jet finding algorithm. The evolution of di-jet rates with W is compared to QCD first order predictions in the W range of 15 to 25 GeV. 7 refs., 3 figs.
Date: August 1, 1991
Creator: Salgado, C.
System: The UNT Digital Library
Radioactivities of Long Duration Exposure Facility (LDEF) materials: Baggage and bonanzas (open access)

Radioactivities of Long Duration Exposure Facility (LDEF) materials: Baggage and bonanzas

Radioactivities in materials onboard the returned Long Duration Exposure Facility (LDEF) satellite have been studied by a variety of techniques. Among the most powerful is low-background Ge-semiconductor detector gamma-ray spectrometry, illustrated here by results obtained at the Lawrence Berkeley Laboratory's (LBL) Low Bakground Facilities, in a multi-laboratory collaboration coordinated by Dr. Thomas Parnell's team at the Marshall Spacecraft Center, Huntsville, Alabama.
Date: August 1, 1991
Creator: Smith, A. R. & Hurley, D. L.
System: The UNT Digital Library
Theoretical understanding of charm decays (open access)

Theoretical understanding of charm decays

A detailed description of charm decays has emerged. The various concepts involved are sketched. Although this description is quite successful in reproducing the data the chapter on heavy flavour decays is far from closed. Relevant questions like on th real strength of weak annihilation, Penguin operators, etc. are still unanswered. Important directions in future work, both on the experimental and theoretical side are identified.
Date: August 1, 1986
Creator: Bigi, I. I.
System: The UNT Digital Library
Suppression of superheavy magnetic monopoles in grand unified theories (open access)

Suppression of superheavy magnetic monopoles in grand unified theories

The superheavy magnetic monopoles predicted by grand unified theories would not be produced in significant numbers if electromagnetic gauge invariance is spontaneously broken when the temperature T is greater than T/sub c/ >approx. 1 TeV.
Date: August 1, 1980
Creator: Pi, S.Y.
System: The UNT Digital Library
Three-dimensional free electron laser dispersion relation including betatron oscillations (open access)

Three-dimensional free electron laser dispersion relation including betatron oscillations

We have developed a 3-D FEL theory based upon the Maxwell-Vlasov equations including the effects of the energy spread and emittance of the electron beam, and of betatron oscillations. The radiation field is expressed in terms of the Green's function of the inhomogeneous wave equation and the distribution function of the electron beam. The distribution function is expanded in terms of a set of orthogonal functions determined by the unperturbed particle distribution. The coupled Maxwell-Vlasov equations are then reduced to a matrix equation, from which a dispersion relation for the eigenvalues is derived. In the limit of small betatron oscillation frequency, the present dispersion relation reduces to the well-known cubic equation of the one-dimensional theory in the limit of large beam size, and it gives the correct gain in the limit of small beam size. Comparisons of our numerical results with other approaches show good agreement. We present a handy empirical formula for the FEL gain of a 3-D Gaussian beam, as a function of the scaled parameters, that can be used for a quick estimate of the grain. 5 refs., 2 figs.
Date: August 1, 1991
Creator: Chin, Y. H.; Kim, K. J. & Xie, M.
System: The UNT Digital Library
Advanced materials for geothermal energy processes (open access)

Advanced materials for geothermal energy processes

The primary goal of the geothermal materials program is to ensure that the private sector development of geothermal energy resources is not constrained by the availability of technologically and economically viable materials of construction. This requires the performance of long-term high risk GHTD-sponsored materials R and D. Ongoing programs described include high temperature elastomers for dynamic sealing applications, advanced materials for lost circulation control, waste utilization and disposal, corrosion resistant elastomeric liners for well casing, and non-metallic heat exchangers. 9 refs.
Date: August 1, 1985
Creator: Kukacka, L. E.
System: The UNT Digital Library