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AN ADVANCED ENGINEERING TEST REACTOR

Description: A concpept for an advanced enineering test reactor is described. Thpe results of various investigations with regard to alternative design possibilitipes are presented. Retailed information is given rearding the nuclear and enineering calculations. (W.D.M.)
Date: March 15, 1958
Creator: Leyse, C.F.; Bertelson, P.C.; Chmielewski, W.S.; Delicate, W.S.; Francis, T.L.; Kornfeld, M.J. et al.
Partner: UNT Libraries Government Documents Department

DESCRIPTION OF PRINTED OUTPUT FROM INTRANUCLEAR CASCADE CALCULATION

Description: ABS>A detailed description of the printed output sheets from the intranuclear cascade calculation described in ORNL3383 is given. The three analysis codes --analysis codes I and II and an evaporation code --that were written to organize the raw data of the output tape are considered. (auth) A tabulation of the neutron total cross section of U/sup 233/ as a function of neutron energy from 0.07 to 10,000 ev, measured with the ORNL fast chopper time- of-flight neutron spectrometer is given. (auth)
Date: May 28, 1963
Creator: Bertini, H.W.
Partner: UNT Libraries Government Documents Department

SOME SIMPLIFIED EXPRESSIONS FOR THE 3-j SYMBOLS

Description: A general formalism is developed for obtaining simplified expressions for the 3-j symbol using the symmetry properties of the symbol discovered by Regge. Some new formulas are derived from the formalism for cases in which Racah's series for the symbol is summable. (auth)
Date: March 15, 1963
Creator: Zerby, C.D. & Coveyou, R.R.
Partner: UNT Libraries Government Documents Department

An Application of Spencer's Method to the Stieltjes and Hamburger Moment Problems

Description: Given the moments of a function it is often desirable to obtain a numerical approximation of the function. A method for estimating the solutions of the Stieltjes and Hamburger moment problems is developed. Calculations indicate that the method is both feasible and accurate. (auth)
Date: July 1, 1959
Creator: Guilinger, W. H.
Partner: UNT Libraries Government Documents Department

NUMERICAL SOLUTION OF TRANSIENT AND STEADY-STATE NEUTRON TRANSPORT PROBLEMS

Description: A general numerical procedure, called the discrete S/sub n/ method, for solving the neutron transport equation is described. The main topics relate to the derivation of suitable difference equations, and to the problem of solving these, while maintaining generality, accuracy, and reasonable computing speed. A few comparisons with other methods are made. (auth)
Date: May 16, 1959
Creator: Carlson, B.
Partner: UNT Libraries Government Documents Department

Construction of an Extended Nuclidic Mass Table

Description: A parabolic systematics approach was used to construct an extended mass table with very small deviations between the calculated and known masses. The masses were obtained from a formula parabolic in 2 after inclusion of the necessary considerations. For 763 masses, the standard deviation was 0.35 Mev, and the largest deviation was 2 Mev. (D.C.W.)
Date: July 1, 1963
Creator: Hillman, M.
Partner: UNT Libraries Government Documents Department

SPECIFIC ACTIVITIES OF NUCLIDES, Z /greater than/ 87

Description: The specific activity of an isotope is expressed as the product of its decay constant and the number of atoms per unit weight. The specific activities of the elements with Z> 87 are calculated in units of disintegrations per minute per microgram. (W.D.M.)
Date: September 1, 1959
Creator: Isaac, N.M. & Wilkins, J.W.
Partner: UNT Libraries Government Documents Department

Variable Metric Method for Minimization

Description: A method for determining numerically local minima of differentiable functions of several variables is presented. In the process of locating each minimum, a matrix which characterizes the behavior of the iunction about the minimum is determined. For a region in which the function depends quadratically on the variables, no more than N iterations are required, where N is the number of variables. By suitable choice of starting values and without modification of the procedure, linear constraints can be imposed upon the variables. (auth)
Date: November 1, 1959
Creator: Davidon, W. C.
Partner: UNT Libraries Government Documents Department

Variable Metric Method for Minimization

Description: A method is presented for numerically determining local minima of differentiable functions of several variables. In the proeess of locating each minimum, a matrix is determined which characterizes the behavior of the function about the minimum. For a region in which thc function depends quadratically on the variables, no more than N iterations are required, where N is the number of variables. By suitable choice of starting values and without modification of the procedure, linear constraints can be imposed upon the variables. (auth)
Date: May 1, 1959
Creator: Davidon, W. C.
Partner: UNT Libraries Government Documents Department

THERMODYNAMIC AND TRANSPORT PROPERTIES OF GASEOUS CARBON DIOXIDE

Description: The thermodvnamic and transport properties of gaseous CO/sub 2/ are presented. The properties were coruputed from the most recent data. The results are presented graphically with pressure and temperature as independent variables for convenience in engineering calculations. (J.R.D.)
Date: August 10, 1959
Creator: Chen, L.H.
Partner: UNT Libraries Government Documents Department

THE ELECTRON THEORY OF SIMPLE METALS AND ALLOYS

Description: The successes and difficulties of the Bloch model of a metal are briefly reviewed, and the Landau quasi-particle theory amd the pseudopotential theory are briefly discussed. These two notions are made the basis for a revised version of the Bloch model that avoids the conceptual difficulties of the original model, while retaining and explaining its appealing features. Well known empirical generalizations concerning the relative importance of conduction-electron density, composition, and structure for the electronic properties are presented, and their implications are reexamined. A theory of the form required by the empirical generalizations is developed. Recent approximate calculations are discussed, and a variety of conclusions are drawn from these relating to the possibility of explanation of the empirical generalizations by the theory. 42 references. (auth)
Date: January 1, 1963
Creator: Cohen, M H
Partner: UNT Libraries Government Documents Department

GENERALIZATION OF THE ACTIVATED COMPLEX THEORY OF REACTION RATES. I. QUANTUM MECHANICAL TREATMENT

Description: In its usual form activated complex theory assumes a quasi-equilibrium between reactants and activated complex, a separable reaction coordinate, a Cartesian reaction coordinate, and an absence of interaction of rotation with internal motion in the complex. In the present paper a rate expression is derived without introducing the Cartesian assumption. The expression bears a formal resemblance to the usual one and reduces to it when the added assumptions of the latter are introduced. The new equation for the transmission coefficient contains internal centrifugal terms. The derivation employs an extension of the Stackel-Robertson formalism for separation of variables in mechanics. The fourth assumption can also be weakened and a rotational interaction included in the formalism. In applications of the rate equation use is made of the recent findings that in the immediate vicinity of a saddle-point or a minimum a potential energy surface can be imitated in some major topographical respects by a surface permitting separation of variables. The separated wave equation for the reaction coordinate is then curvilinear because of the usual curvature of the path of steepest ascent to the saddle-point. Calculations of transmission coefficients and rates can be made and compared with those obtainable from the usual one-dimensional Cartesian-like calculations on the one hand and with some based on the numerical integration of the n-dimensional Schrodinger equation on the other. An application to a common three-center problem is discussed.
Date: November 1, 1964
Creator: Marcus, R.A.
Partner: UNT Libraries Government Documents Department

A MODEL DESIGNED TO PREDICT THE MOTION OF OBJECTS TRANSLATED BY CLASSICAL BLAST WAVES

Description: BS>A theoretical model was developed for the purpose of predicting the motion of objects translated by winds associated with "classical" blast waves produced by explosions. Among the factors omitted from the model for the sake of simplicity were gravity and the friction that may occur between the displaced object and the surface upon which it iritially rested. Numerical solutions were obtained (up to the time when maximum missile velocity occurs) in terms of dimensionless quantities to facilitate application to specific blast situations. The results were computed within arbitrarily chosen limits for blast waves with shock strengths from 0.068 to 1.7 atm (1 to 25 psi at sea level) for displaced objects with aerodynamic characteristics ranging from those of a human being to those of 10-mg stones and for weapon yields at least as small as 1 kt or as large- as 20 Mt. (auth)
Date: January 1, 1961
Creator: Bowen, I.G.; Albright, R.W.; Fletcher, E.R. & White, C.S.
Partner: UNT Libraries Government Documents Department

VIBRATIONAL ASSIGNMENT AND FORCE CONSTANTS OF S$sub 8$ FROM A NORMAL- COORDINATE TREATMENT

Description: Normal-coordinate calculations for the S/sub 8/ molecule were revised by use of new far-infrared spectral data and a more elaborate potential function. Representation of the observed frequencies required that the basic Urey--Bradley field be supplemented with an extra quadratic cross-term between adjacent S--S bonds. (auth)
Date: January 1, 1962
Creator: Kruse, F. H.; Scott, D. W. & McCullough, J. P.
Partner: UNT Libraries Government Documents Department