Effect of Long-Range Interactions on Order (open access)

Effect of Long-Range Interactions on Order

Harrison and Paskin (HP) have calculated the ordering energy of β-CuZn using recent theoretical techniques of treating electron screening and Mott's polar model of an alloy. Good agreement is obtained between the calculated total energy of the order-disorder transformation and specific heat measurements. A consequence of the HP calculation is that the ordering energy is long-range and oscillates in sign. Walker and Keating recently measured the neutron diffuse scattering of β-CuZn above the critical temperature Tc and find their data is in agreement with order calculated by only considering a nearest neighbor interaction. Using the Cowley statistical theory of order, we compare the order generated by a nearest-neighbor interaction and the long-range interaction of HP at a temperature 1.1Tc. we find the average behavior of the order generated by the nearest-neighbor and long range interaction to be similar, The major difference is the nearest-neighbor interaction generates order that asymptotically, varies smoothly with neighbor distance whereas the order resulting from the long-range interaction fluctuates markedly about the nearest-neighbor generated order. This result may explain the success of statistical theories, based on nearest-neighbor interactions, in both order-disorder of alloys as well as in some magnetic systems which are also believed to have …
Date: December 24, 1963
Creator: Paskin, Arthur
System: The UNT Digital Library
Light-Droven Cytochrome Reactions in Anacystis and Euglena (open access)

Light-Droven Cytochrome Reactions in Anacystis and Euglena

The basic similarity in cytochrome physiology between Anacystis nidulans ad Euglena gracilis, strains Z, is impressive in view of their gross dissimilarities in size, structure, and pigment content. We have investigated the cytochrome reactions by sensitive spectrophotometric methods in order to gain some insight into the patterns of energy transfer from the various light receptors to the reaction centers involved in the two photochemical reactions of green plant photosynthesis and also to elucidate the pathways of photosynthetic electron transfer. The major thrust of this presentation will be the implications of experiments on whole cells in which both wavelength and intensity of monochromatic actinic light have been systematically varied. Some preliminary observations of the effect of carbonyl cyanide-m chlorophenylhydrazone (CCCP) are presented, and the light-driven reduction of cytochrome b6 in Euglena chloroplast fragments is described.
Date: December 24, 1963
Creator: Olson, John M.
System: The UNT Digital Library
Manganese Poisoning - New Insights (open access)

Manganese Poisoning - New Insights

The heavy metal intoxications involving the brain may be divided into two groups: One, in which the offending metal is clearly a poison, such as mercury or lead; and a second, in which the offending agent is normally an essential constituent of the body. The latter category would include manganese poisoning, copper poisoning (or Wilson's disease) and, if some recent data are valid, Huntington's chorea, in which iron seems to have been implicated. Our interest in the second category of diseases is due to the fact that these conditions represent special aberrations of normal homeostasis. Homeostasis is the sum of the processes which maintain constant structure, function and constitution in the body and its organs. In manganese poisoning, the homeostatic control is disturbed by virtue of oversupply of this element via an abnormal route (the respiratory tract), while in Wilson's disease homeostasis is disturbed by virtue of genetically transmitted abnormal avidity of the body for dietary copper. In the present paper, we will discuss first some of the clinical features of chronic manganese poisoning in order to raise some questions about extrapyramidal syndrome in general. Thereafter, we will allude to some investigations conducted at this center during the last ten …
Date: December 24, 1963
Creator: Cotzias, George. C. & Van Woert, Melvin H.
System: The UNT Digital Library
A Model for Current Reversal Chronopotentiometry with Kinetic Complications (open access)

A Model for Current Reversal Chronopotentiometry with Kinetic Complications

A model has been developed for the analysis of current reversal chronopotentiograms in systems where the electrode process is followed by a homogeneous second order reaction. The model is analyzed using the IBM 7094 digital computer programed in FORTRAN language. Working curved, derived with the aid of dimensional analysis, can be used to evaluate rate constants from experimental data. The electroreducation of uranium (VI) to uranium (V) with subsequent second order disproportionation of uranium (V) has been studied as an experimental test of the model. Disproportionation rate constants thus obtained are in satisfactory agreement with previously reported values. Other possible applications of the model are discussed.
Date: December 24, 1963
Creator: Feldberg, S. W. & Auerbach, Clemens
System: The UNT Digital Library
Neutron Activation Analysis: Clinical and Biological Studies of Manganese (open access)

Neutron Activation Analysis: Clinical and Biological Studies of Manganese

A strong motivation for metabolic investigations of essential metals lies with the simple fact that these elements are primordial metabolites and building blocks of living matter, a truism largely forgotten today. Among them, the metals of the first transition group display high physical and chemical flexibility: They can concomitantly coordinate natural or artificial ligands; they can regulate electron and proton transport; they can act as catalysts or as cofactors to catalysis.
Date: December 24, 1963
Creator: Cotzias, G. C.; Papavasiliou, P. S. & Miller, S. T.
System: The UNT Digital Library
Past Analogue Multipliers with Field-Effect Transistors (open access)

Past Analogue Multipliers with Field-Effect Transistors

The solution time of analogue multipliers using field-effect transistors is investigated. This time is ultimately limited by the charging time of the field-effect transistor junction. In typical devices suitable for analogue multiplication the charging time is found to be about 10-20 nsec less than one percent. A four quadrant pulse amplitude multiplier circuit is described, whose solution time is equal to the field-effect transistor charging time.
Date: December 24, 1963
Creator: Radeka, V.
System: The UNT Digital Library
Recent Studies on the Experimental Program Requirements for a Super High Energy Accelerator (open access)

Recent Studies on the Experimental Program Requirements for a Super High Energy Accelerator

Brookhaven has sponsored a summer program to study possible experimentation with super-high-energy accelerators of ~ 1000 BeV and to examine the feasibility of colliding beam experiments. A group of about fifty physicists took part in this study program. These investigations are a continuation and supplementary to our previous studies at Brookhaven about two years ago.
Date: December 24, 1963
Creator: Yuan, Luke C. L.
System: The UNT Digital Library
The Use of Low Energy Radioactive Isotopes in The Examination of Paintings on Thin Supports (open access)

The Use of Low Energy Radioactive Isotopes in The Examination of Paintings on Thin Supports

The importance of the examination of paper and textile supported art objects by means of low energy X-rays has been ably discussed in the preceding papers of this session. The apparatus used for such radiography, however, has tended to be both expensive and confined to laboratory use. A lack of mobility arises from the weight and size of X-ray apparatus and the fact that its installation frequently requires shielding and special electric power lines. An inexpensive radiographic apparatus that required no special installation or external power and is small and light enough to be easily portable should be quite useful.
Date: December 24, 1963
Creator: Sayre, E. V.
System: The UNT Digital Library
Application of the Variational Method to the Calculation of the Time Dependence of the Neutron Flux in Small Pulsed Slabs, Cylinders and Spheres (open access)

Application of the Variational Method to the Calculation of the Time Dependence of the Neutron Flux in Small Pulsed Slabs, Cylinders and Spheres

The variational method is applied to the monoenergetic time dependent transport equation to obtain a simple relation for the asymptotic decay constant in small pulsed assemblies. The results indicate that flat trial functions may be a reasonable representation of the flux distributions in the thin slab limit. This approach is superior to many of the usual transport approximations.
Date: December 16, 1963
Creator: Judge, F. D. & Daitch, Paul B. (Paul Bernard), 1925-
System: The UNT Digital Library
Evaluation of Resonance Capture Approximations (open access)

Evaluation of Resonance Capture Approximations

The program KRUDE, which solves the slowing down and adjoint equations for a mixture of resonance and nonresonance isotopes in an infinite homogeneous medium, was used to evaluate some resonance capture approximations (variational and successive) that use linear combinations of narrow and wide resonance fluxes. Results obtained for resonance capture in the 291-ev resonance of Zr/sup 91/ and the 192-ev resonance of U/sup 238/ are compared, and three methods for including Doppler effects in the variational method are considered.
Date: December 16, 1963
Creator: Edgar, K. R.
System: The UNT Digital Library
Determination of the Nucleon-Nucleon Elastic Scattering Matrix : I. Phase Shift Analysis of Experiments Near 140 MEV (open access)

Determination of the Nucleon-Nucleon Elastic Scattering Matrix : I. Phase Shift Analysis of Experiments Near 140 MEV

A phase shift analysis is an attempt to translate experimental measurements (observables) into well-determined scattering amplitudes, since these are the quantities that can be readily compared with theoretical predictions, In this sense, the phase shift analysis should contain as little theory as possible. The scattering amplitudes (or phase shifts) constitute an experimental statement, and the phase shift analysis should logically be done by the experimental groups who measure the observables.
Date: December 6, 1963
Creator: MacGregor, Malcolm. H. (Malcolm Herbert), 1926-2019; Arndt, R. A. & Dubow, A. A.
System: The UNT Digital Library
[Delta]I = 1/2 Rule for Non-Leptonic Strangeness-Changing Decay Processes (open access)

[Delta]I = 1/2 Rule for Non-Leptonic Strangeness-Changing Decay Processes

Gell-Mann and Pais were the first to suggest that the non-leptonic decay processes of strange particles may be subject to an isospin selection rule, allowing only those decay transitions which involve a change [delta]I = 1/2 in to total isopin of the system. At present, however, there is really no theoretical framework for the description of weak interactions into which this selection rule fits in a natural and compelling way. The report includes sections on the 91) decay processes of the [caret] hyperon, (2) decay processes, (3) [complex conjugate] decay processes, and (6) K[pi]3 decay processes. We have considered the evidence on all of the known non-leeptonic non-radiative decay modes of strange particles. All of this evidence is in good qualitative accord with the [delta]I = 1/2 selection rule.
Date: December 2, 1963
Creator: Dalitz, R. H. (Richard Henry), 1925-2006.
System: The UNT Digital Library
Two-Phase Pressure Losses Quarterly Progress Report: Seventh Quarter, August 12, 1963 - November 11, 1963 (open access)

Two-Phase Pressure Losses Quarterly Progress Report: Seventh Quarter, August 12, 1963 - November 11, 1963

Technical report describing that the pressure drop along an annular channel with dimensions D(1) = 0.375 inch; D(2) = 0.875 inch, L = 70 inches. Flow was vertical and upward, and only the internal surface was heated. Subcooled conditions existed at the inlet, with two-phase conditions at the exit. Groups of three radial spacer pins on 18-inch centers along the channel, held the inner surface concentric with the outer surface. The single phase loss coefficient for each spacer group is K(8) = 0.21. The single phase friction factor for the annual channel is given by f = 0.16 N(R)(-0.16). The two phase pressure drop increases as the quality increases for G [over] 10(6) = 0.5 ;b/hr ft(2). The effect of heat flux on the pressure drop is very is very slight over the range of fluxes tested (0.55 less than or equal to Q over 10(6).\ less than or equal to 0.8). The two-phase pressure drop gradient in the same annulus, with no heat addition is qualitatively the same as for a 1/4-inch by 1-3/4 inches rectangular channel but is quantitatively greater than for the rectangular channel.
Date: December 2, 1963
Creator: Janssen, E. (Engineer) & Kervinen, J. A.
System: The UNT Digital Library
Accurate Nuclear Fuel Burnup Analyses; Eighth Quarterly Progress Report, (September - November 1963) (open access)

Accurate Nuclear Fuel Burnup Analyses; Eighth Quarterly Progress Report, (September - November 1963)

The objective of the Accurate Nuclear Fuel Burnup Analyses program is to develop more accurate methods for burnup analysis for general use than the current method of analysis of Ca-137 or Sr-90. The program will require from three to five years of effort.
Date: December 1, 1963
Creator: Rider, B. F.; Ruiz, C. P.; Luke, P. S., Jr.; Peterson, J. P., Jr. & Smith, F. R.
System: The UNT Digital Library
The Class of Shocks With Uniform Pressure (open access)

The Class of Shocks With Uniform Pressure

If a piston with constant velocity moves into a shock tube containing material at rest and at uniform density, the result is well known and trivial. The shock propagates with uniform speed, the state and speed of the material behind the shock is constant. One can ask if similar flows exist for cylindrical of spherical symmetry. Quickly one rules out the possibility of a solution which retains all the properties of this trivial solution. One asks if there are any solutions such that the material behind the shock is not accelerated. Indeed, there are. In the following, it is shown that for a y-law gas, there is a family of densities such that if a piston moves into the material with uniform velocity, the material behind the shock is not accelerated. Further, these are the only densities with this property. In the case of planar symmetry, the trivial case mentioned above is a member of the family, as is to be expected.
Date: December 1963
Creator: Hardy, John W.
System: The UNT Digital Library
EVESR Nuclear Superheat Fuel Development Project: Sixth Quarterly Report, September - November, 1963 (open access)

EVESR Nuclear Superheat Fuel Development Project: Sixth Quarterly Report, September - November, 1963

Quarterly report describing progress on the EVESR Nuclear Superheat Fuel Development Project.
Date: December 1963
Creator: Pennington, R. T.
System: The UNT Digital Library
Irradiation of Beryllium at Elevated Temperatures. Part II. Irradiation of Rig X-74 in HIFAR (open access)

Irradiation of Beryllium at Elevated Temperatures. Part II. Irradiation of Rig X-74 in HIFAR

Beryllium metal specimens fabricated by various routes were examined after irradiation to fast neutron doses of 5.5 x 1020 to 9 x 1020 nvt at temperatures of 450, 550, and 650ºC. The results were in general agreement with those reported previously for similar material irradiated to lower doses. Density changes of any significance were observed only at 650ºC. Serious loss of high temperature ductility occurred in all materials and was again attributed to helium bubble formation at grain boundaries. Material fabricated by hot pressing and extrusion showed superior properties, both before and after irradiation, to material prepared by loose sintering and extrusion.
Date: December 1963
Creator: Hickman, B. S. (Brian Stuart) & Bannister, G.
System: The UNT Digital Library
MULGA : a Complex of Codes for the Determination of Multigroup Averaged Neutron Cross Section Data (open access)

MULGA : a Complex of Codes for the Determination of Multigroup Averaged Neutron Cross Section Data

A complex of computer programmes called MULGA is described which will produce multigroup cross sections in a format suitable for input into a selection of reactor codes. Always bearing in mind that the spatial variation of flux will frustrate any determination of "exact" cross sections the maximum accuracy has been striven for within the limitations of urgency and feasibility. The programmes; together with an associated microscopic data library tape, and a specialised monitor system, have been coded for an IBM 1620 computer with 4 magnetic tapes. The basic programmes MULGA 1 and MULGA 2 have already been adapted for an ISM 7090 and the whole series will be modified for the new site computer in 1964.
Date: December 1963
Creator: Clancy, B. E.; Doherty, G.; Keane, A.; Kletzmayr, E. & Pollard, J. P.
System: The UNT Digital Library
Two Modes of Pulse Recording on Magnetic Tape (open access)

Two Modes of Pulse Recording on Magnetic Tape

Methods and equipment are described whereby electrical pulses are recorded on magnetic tape in two different ways, using a commercial, single-track type deck, The first method is used to record count rate information regarding regularly or randomly occurring pulses. Random count rates up to approximately 2,000 per second can be directly recorded without serious dead-time loss. By the addition of a simple, high-resolution scale-of-4, the input count rate can be increased to approximately 20,000 per second. By the other method information about relative pulse amplitude as well as count rate is recorded. The usable amplitude analogue output corresponds to an input range of at least 7 to 1, with linearity of approximately 1 1/2 per cent of maximum amplitude. Amplitude resolution of 2 to 3 per cent is obtained over the upper 70 per cent of the range. Transistorized circuitry is described which enables the output pulses of the tape recorder to be analyzed by a Radiation Counter Laboratories Inc. 256 channel scaler-analyzer.
Date: December 1963
Creator: Fookes, R. A.
System: The UNT Digital Library
Acceleration of Deuterons or Alpha Particles in the AGS (open access)

Acceleration of Deuterons or Alpha Particles in the AGS

The magnetic field of the AGS ring can contain particles of magnetic rigidity about 34 Bv/c. This includes not only protons of kinetic energy 33 Bev, but also 32 Bev deuterons, 64 Bev alpha particles, and conceivably heavier nuclei such as 188 Bev carbon nuclei. It will be shown in this paper that such nuclei can be injected and accelerated in the AGS if some rather small modifications are made in the injection and acceleration systems. What physics could be done with such beams? Several types of experiments may be suggested. In the first place, since the deuteron is a rather loosely bound combination of a neutron and a proton, it is likely to break up when it hits a target nucleus (stripping reaction). In a considerable fraction of the collisions the neutron will go straight on with essentially unchanged energy (half the deuteron energy). Therefore, with an internal target bombarded by 30 Bev deuterons one should obtain an intense, rather well collimated and monochromatic beam of 15 Bev neutrons in the forward direction.
Date: December 28, 1962
Creator: Courant, E. D.
System: The UNT Digital Library
HAPO IB Fission Product Shipping Cask Design Evaluation Report (open access)

HAPO IB Fission Product Shipping Cask Design Evaluation Report

As a result of the interest in fission products for use as heat sources and/or radiation sources, in early 1960. Hanford was authorized to supply a semi-refined cerium-144 rare earth product to Oak Ridge National Laboratories. Facilities were installed for collecting this product and a cask war designed for shipping this product as a stabilized, dry powder. Since that time, numerous improvements have been made in the design of the HAPO I cask as described in Revision O of this document. In addition, the development of strontium-90 as a major product requires increased flexibility in the utilization of these casks.
Date: December 28, 1962
Creator: Smith, C. W.
System: The UNT Digital Library
Heavy Element Isotopic Analysis of UO2 Fuel Irradiated In The VBWR: Report #1 (open access)

Heavy Element Isotopic Analysis of UO2 Fuel Irradiated In The VBWR: Report #1

The primary objective of this program is to obtain improved data on the changes in nuclear characteristics with burnup of uranium oxide fuel in a boiling water reactor.
Date: December 28, 1962
Creator: Hackney, M. R. & Ruiz, C. P.
System: The UNT Digital Library
A Correlation for Boiling Heat Transfer to Saturated Fluids in Convective Flow (open access)

A Correlation for Boiling Heat Transfer to Saturated Fluids in Convective Flow

An additive mechanism of micro- and macro-convective heat transfer was formulated to represent boiling heat transfer with net vapor generation to saturated, non-metallic fluids in convective flow. The final equations are [equations not transcribed]. The second equation will be recognized as the Dittus-Boelter equation with the additional factor F. The two functions F and S are defined as [equations not transcribed] where Re is the effective Reynolds number for the two-phase fluid and ΔTe is the effective superheat for bubble growth. F and S were obtained as functions of the Martinelli parameter and the two-phase Reynolds number, respectively. The correlation was tested with available data for water and organic fluids. Data from different sources which could not be satisfactorily correlated by existing correlations were shown to be quite well correlated by the one presently proposed. The average deviation between calculated and measured boiling coefficients for all data points from nine experimental cases was ±11%
Date: December 26, 1962
Creator: Chen, John C.
System: The UNT Digital Library
Influence of Low Concentrations of Crystal Defects on Thermal Annealing of Recoil Br82 in Hexabromoethane (open access)

Influence of Low Concentrations of Crystal Defects on Thermal Annealing of Recoil Br82 in Hexabromoethane

When the nucleus of an atom in a crystalline solid undergoes radiative neutron capture there is disruption of the crystal in the vicinity of the event due to energetic processes accompanying the nuclear transformation. This local disruption has been termed a "hot-zone" or "displacement spike". The chemical state of a transformed recoil atom immediately following transformation is unknown. Within a microsecond the "hot zone" has cooled sufficiently to "freeze" the recoil atom into a stable (or metastable) chemical state. A fraction of the metastable recoil atoms can undergo thermal annealing reactions, and the chemical nature of the metastable state can sometimes be inferred from annealing data. It is characteristic of these reactions that the recoil atoms tend to be reincorporated into the parent chemical form.
Date: December 20, 1962
Creator: Collins, Kenneth E. & Harbottle, Garman
System: The UNT Digital Library