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Comparison of Radiation-Induced Graft Copolymerization Untilizing Electron Accelerators and Isotope Sources as Radiation Initiators (open access)

Comparison of Radiation-Induced Graft Copolymerization Untilizing Electron Accelerators and Isotope Sources as Radiation Initiators

"A comparison of grafting to two thicknesses of polypropylene film is made using isotope and electron accelerator initiation. The results indicate that the grafting of methacrylic acid: styrene to polypropylene is mainly a surface reaction."
Date: September 12, 1961
Creator: Odian, George; Oliver, William F. & Pierre, Karl
System: The UNT Digital Library
Comparison of Radiation-Induced Graft Copolymerization Untilizing Electron Accelerators and Isotope Sources as Radiation Initiators (open access)

Comparison of Radiation-Induced Graft Copolymerization Untilizing Electron Accelerators and Isotope Sources as Radiation Initiators

"Graft polymers were made by Co60 mutual irradiation of mixtures of styrene and methyl acrylate in contact Teflon. These graft copolymers were analyzed by infra-red absorption and their composition determined. The composition of the graft copolymer formed from styrene and methyl acrylate was different from that which is predicted by the copolymer composition equation."
Date: May 8, 1961
Creator: unknown
System: The UNT Digital Library
Comparison of Radiation-Induced Graft Copolymerization Untilizing Electron Accelerators and Isotope Sources as Radiation Initiators (open access)

Comparison of Radiation-Induced Graft Copolymerization Untilizing Electron Accelerators and Isotope Sources as Radiation Initiators

"A brief examination of the post irradiation grafting of machine irradiated polyethylene film with acrylic acid monomer was made. Evidence of postgrafting was detected in samples that had been irradiated to a total dose of 10 Mrads at a dose rate of 0.01 Mrad/sec. and then exposed to a 25% purified acrylic acid solution in benzene for periods of 1 to 4 days."
Date: October 17, 1961
Creator: unknown
System: The UNT Digital Library
Self-Diffusion in α-Iron During Compressive Creep (open access)

Self-Diffusion in α-Iron During Compressive Creep

"The influence of compressive creep on the self-diffusivity of α-iron has been measured in the temperature range of 742-885°C. the diffusivity is enchanced in proportion to the strain rate, but this dependence decreases with increasing temperature. The magnitude of the strain is relatively unimportant in this connection. Strain rates from 0 to -2 x 10¯³ sec¯¹ were investigated with a corresponding increase in diffusivity up to 3 x 10³ times. The results are analyzed in terms of vacancy diffusion and the excess vacancies introduced during deformation. It is concluded that grain boundaries are the main vacancy sinks in polycrystalline iron and that the vacancy lifetime is therefore dependent on the grain size."
Date: May 29, 1962
Creator: Hirano, Ken-ichi; Averbach, B. L. & Cohen, Morris
System: The UNT Digital Library
Coolball, a Machine Code for Thermal Analysis of Pebble Bed Reactor Cores (open access)

Coolball, a Machine Code for Thermal Analysis of Pebble Bed Reactor Cores

COOLBALL is an IBM 650 machine program designed to calculate local gas and ball temperatures, gas flow, and pressure loses as induced by non-uniform power generation and voidage within an axial flow Pebble Bed Reactor core. This code has been used extensively to study the thermal characteristics of Pebble Bed Reactor cores in support of a broad program for the development of the PBR concept.
Date: 1961?
Creator: unknown
System: The UNT Digital Library
Bimetallic Casting (open access)

Bimetallic Casting

"The purposes of the program being conducted under the present contract are: 1) To determine the feasibility of cladding zirconium on uranium by a direct casting process. 2) To investigate the diffusion of liquid metals in the fusion zone."
Date: March 29, 1961
Creator: Krashes, David
System: The UNT Digital Library
Fifth Quarterly Progress Report on Fission Product Applications Using Gaseous Beta Sources (open access)

Fifth Quarterly Progress Report on Fission Product Applications Using Gaseous Beta Sources

"Rates of acetylene polymerization induced by Kr/sup 85/ in d-c fields were up to 15 times greater than those observed when no fields were imposed. Work to determine the relations between acetylene pressure, Kr/sup 85/ concentration, and the field intensity is continuing. In other activities, equipment is being designed to study the effects of megacycle electric fields on radioinduced chemical reactions."
Date: October 31, 1961
Creator: Graessley, William W. & Zufall, John W.
System: The UNT Digital Library
Some Problems in Linear Graph Theory That Arise in the Analysis of the Sequencing of Jobs Through Machines (open access)

Some Problems in Linear Graph Theory That Arise in the Analysis of the Sequencing of Jobs Through Machines

"The problems of sequencing jobs through machines are discussed in a linear graph framework. The construction of feasible schedules from given technological orderings is related to the construction of transitive graphs from given component graphs. Methods of constructing transitive graphs are given and bounds on the number of different transitive graphs constructed from given components are determined. A recursive convex function defined on the transitive graphs-the job operation completion time and schedule time-is studied. Bounds on the number of different values that the schedule time can attain is obtained. Examples of multiprogramming, flow shop and machine shop scheduling are studied."
Date: October 15, 1960
Creator: Heller, Jack
System: The UNT Digital Library
Atom Arrangements in Some Iron-Aluminum Solutions, Report No. 1 (open access)

Atom Arrangements in Some Iron-Aluminum Solutions, Report No. 1

"Short-range order coefficients were measured at 300 and 400°C for iron-aluminum alloys containing 14.8, 18.2, and 20.0 atomic per cent aluminum. These alloys exhibited a strong preference for unlike near neighbors. The short-range order was greater at the lower temperature and increased as the Fe 3Al composition was approached."
Date: July 12, 1962
Creator: Houska, C. R. & Averbach, B. L.
System: The UNT Digital Library
A Theorectical Treatment of Atomic Configurations Found in Some Iron-Aluminum Solid Solutions (open access)

A Theorectical Treatment of Atomic Configurations Found in Some Iron-Aluminum Solid Solutions

"Theoretical calculations have been carried our for the two ordering phases which occur in the FeAl system. The statistical treatment involves first and second neighbor interaction parameters as well as a magnetic interaction between first neighbor iron atoms. The phase diagram and the amount and type of long range order for slowly cooled alloys are calculated. Further calculations include short range order for the disordered phase at three compositions and two temperatures. As expected, the short range order increases as a critical temperature is approached either in composition of in temperature."
Date: July 12, 1962
Creator: Houska, C. R.
System: The UNT Digital Library
Some methods of surface analysis for the prediction of thermal resistance of metal contacts (open access)

Some methods of surface analysis for the prediction of thermal resistance of metal contacts

"Equations for the heat-transfer coefficient existing at the interface of two metals in contact are discussed. The results of applying the equations (with a graphical determination of the geometric parameters) to an iron--aluminum contact are presented. A method is given for performing the graphical analysis by means of a general purpose analog computer. Data are included that were obtained by applying this method to Blanchard ground stainless steel surfaces in contact. Statistical analysis was applied to surfaces to determine the geometric properties of the contact as a function of root-mean-square roughness and method of surface preparation."
Date: November 1, 1961
Creator: unknown
System: The UNT Digital Library
An Algorithm for Construction Feasible Schedules and Computing Their Schedule Times (open access)

An Algorithm for Construction Feasible Schedules and Computing Their Schedule Times

"An algorithm for the generation of feasible schedules and the computation of the completion times of the job operations of feasible schedule is presented. Using this algorithm, the distribution of schedule times over the set of feasible schedule—or a subset of feasible schedules—was determined for technological orderings that could occur in a general machine shop. These distributions are found to be approximately normal. Biasing techniques corresponding to “first come first serve,” random choice of jobs ready at each machine and combinations of these two extremes were used to compute distributions of schedule times."
Date: November 15, 1960
Creator: Heller, Jack & Logemann, George
System: The UNT Digital Library
On the Green's Function for Two-Dimensional Magnetohydrodynamic Waves. II (open access)

On the Green's Function for Two-Dimensional Magnetohydrodynamic Waves. II

"As an extension of an earlier paper the Green's function is evaluated for the Lundquist equation linearized about uniform magnetic field, constant matter density, and zero flow velocity. It is assumed that all quantities are functions of two space variables and time only. In the general magnetic field configuration considered here a pure Alfvén disturbance no longer exists; there is instead a wave with properties of both the Alfvén and fast‐slow disturbance."
Date: December 15, 1960
Creator: Weitzner, Harold
System: The UNT Digital Library
Diffusion of Iron, Cobalt, and Nickel in Gold, Report No. 5 (open access)

Diffusion of Iron, Cobalt, and Nickel in Gold, Report No. 5

"The diffusivities of Fe, Co, and Al in otherwise pure Au were determined by a residual activity technique. It was found that the frequency factors and activation energies of the transition elements into Au are normal relative to the values for Au self-diffusion, and suggest that lattice diffusion is operative, in contrast to the corresponding situation for the diffusion of these elements in Al. This difference in behavior is explained in terms of the marked difference in solid solubilities in the two series."
Date: June 6, 1962
Creator: Duhl, David N.; Hirano, Ken-ichi & Cohen, Morris
System: The UNT Digital Library
Diffusion in Cobalt-Nickel Alloys, Report No. 4 (open access)

Diffusion in Cobalt-Nickel Alloys, Report No. 4

The self-diffusivities of Co60 and Ni63 in cobalt--nickel solid solutions exhibit a greater activation energy below the Curie temperature (T/sub c/) than above. Values of DELTA Q = Q (ferromagnetic) -- Q (paramagnetic) are approximately equal to RT/sub c/. This observation is interpreted to indicate that the increment in activation energy arises from an increase in the formation energy of a vacancy in the ferromagnetic lattice, with the additional binding energy arising from the interaction of a spin with the Weiss field."
Date: June 6, 1962
Creator: Hirano, Ken-ichi; Agarwala, R. P.; Averbach, B. L. & Cohen, Morris
System: The UNT Digital Library
Experimental Determination of Contact Conductance for Some Stainless Steel Contacts (open access)

Experimental Determination of Contact Conductance for Some Stainless Steel Contacts

"Contact conductances for three semi-smooth and rough stainless steel contacts involving six steels are determined. The procedure and equipment used are fully described, and the results are given. Graphs display thermal conductance and conductivity versus pressure and temperature."
Date: July 1962
Creator: Adamantiades, Achilles
System: The UNT Digital Library
Thermal Conductance of Metallic Surfaces in Contact (open access)

Thermal Conductance of Metallic Surfaces in Contact

"Research in thermal contact resistance at MIT and advances made during the past year are summarized. The problem of predicting cortact resistance is examined in an analysis of a model for the contact which relates the geometry of actual surfaces in contact to the contact model, and a deformation analysis which relates the contact geometry to the load carried by the surfaces. Experimental procedures are described and are applied to two stainless steel surfaces in contact and to W and graphite surfaces in contact. A significant result is that a surface may be described by two measurable parameters which may be combined with two such parameters of any other surface to completely determine the geometry of the interface if they are placed in contact. It thus remains to construct a device which will readily measure these two parameters."
Date: February 1963
Creator: Henry, John Jewett
System: The UNT Digital Library
The Effect of Temperature on the Width of a Small-Amplitude, Solitary Wave in a Collision-Free Plasma (open access)

The Effect of Temperature on the Width of a Small-Amplitude, Solitary Wave in a Collision-Free Plasma

"Adlam and Allen and Davis, Lust, and Schluter have studied nonlinear plane-waves, propagating normal to the magnetic field, in a cold plasma. One solution of particular interest is a solitary wave, or single pulse. We present a method for solving the analogous problem for a plasma with finite temperature, in the limiting case where the amplitude of the wave is small and where, consequently, the width of the waver is very large."
Date: March 15, 1961
Creator: Gardner, Clifford S.
System: The UNT Digital Library
Alternating Direction and Semi-Explicit Difference Methods for Parabolic Partial Differential Equations (open access)

Alternating Direction and Semi-Explicit Difference Methods for Parabolic Partial Differential Equations

"The energy method is applied to study the stability of two types of difference approximations to parabolic partial differential equations, the alternating direction methods Douglas, Peaceman, and Rachford, and a new semi- explicit method. Each difference scheme is proved to be unconditionally stable. These results apply to parabolic equations with variable coefficients, defined in cylindrical domains with an essentially arbitrary bounded base."
Date: March 1, 1961
Creator: Lees, Milton
System: The UNT Digital Library
The Motion of a Charged Particle Near a Zero Field Point (open access)

The Motion of a Charged Particle Near a Zero Field Point

"The behavior of charged particles in a plasma-free cusp field, or in a cusp field where there is very little plasma, is studied. The numerical computations described may provide a valid picture of the behavior of particles outside such a body of plasma or in the early stages of creation of such a cusped plasma in the low- beta limit. The computations provide a striking illustration of orbits which neither have constant magnetic moment nor behave so irregularly as to defy explanation."
Date: July 15, 1961
Creator: van Norton, Roger
System: The UNT Digital Library
Sherwood progress report no. 4, July 1959 - December 1960 (open access)

Sherwood progress report no. 4, July 1959 - December 1960

"Activities related to Project Sherwood are summarized under the following topics: propagation of waves, macroscopic magneto-fluid dynamics, stability, particle orbits, cusped geometries, collisionless shock theory, and other subjects."
Date: March 1, 1961
Creator: Grad, Harold, 1923-
System: The UNT Digital Library
Some Computational Methods for the Study of Diatomic Molecules (open access)

Some Computational Methods for the Study of Diatomic Molecules

"The present work describes some computer-oriented techniques for the application of the laws of quantum mechanics to the problems of determining basic structure of diatomic molecules. At times, calculations of the type described here yield results which can be compared directly with experiment to check the validity of the hypotheses and technique used they may predict the results of unobserved experimental phenomena; and, in many instances, they provide quantities which are necessary for the interpretation of experimental data but which cannot be directly measured."
Date: May 1, 1961
Creator: Cooley, James W.
System: The UNT Digital Library
The Boundary Layer Between a Plasma and a Magnetic Field - I (open access)

The Boundary Layer Between a Plasma and a Magnetic Field - I

"The problem of a steady boundary layer or sheath between a plasma and a magnetic field is considered. A self-consistent transition layer is found which joins a uniform magnetic field at plus infinity with a collisionless field-free plasma region with arbitrary velocity distribution at minus infinity, i.e., a magnetic field profile is found such that the exact particle orbits in this field produce a current which gives rise to this field. An interesting feature of the solution is that, with any nonsingular velocity distribution at minus infinity, the magnetic field the plasma extends to infinity, exponentially attenuated, into the magnetic field region. The scale of length is the Larmor radius. Electric fields arising from charge separation in the case of particles of different mass are ignored."
Date: December 28, 1960
Creator: Grad, Harold, 1923-
System: The UNT Digital Library
Annual Progress Report of Methods to Increase Burnout Heat Transfer (open access)

Annual Progress Report of Methods to Increase Burnout Heat Transfer

"Acoustic energy generated by mechanical or electrical signals and its effect on pool boiling of isopropanol were studied. Daring the course of the investigation, a method was devised to determine the amount of heat-transfer surface wetted by the boiling isopropanol. Plots of heat flux versus temperature difference for each frequency showed that the acoustic energy did not significantly affect the heat flux at burnout, but slightly increased the critical temperature difference. No general effect of frequency variation was found even at the frequencies of the "boiling songs" of isopropanol. The over- all effect of the acoustic energy was to disturb the vapor tending te coat the heat transfer surface. This was most evident from the absence of film boiling even at temperature differences far above the critical temperature difference. The application of alternating current to the boiling system gives promise of a self-regulating method to increase boiling heat transfer when required, and is the most significant new finding of this investigation. Two pertinent Russian papers were translated and are appended."
Date: September 30, 1960
Creator: Markels, Michael; Durfee, Robert L. & Richardson, Robert
System: The UNT Digital Library