Conference Publications
This community mainly contains citations, yet where permitted, the full text, of the conference papers, presentations, posters and abstracts written by ANSTO authors.
Browse
Browsing Conference Publications by Issue Date
Now showing 1 - 20 of 2489
Results Per Page
Sort Options
- ItemAnalytical chemistry in atomic energy(Melbourne University Press on behalf of The Australian Atomic Energy Commission, 1958-06-02) Smythe, LEThe requirements for analytical chemistry in atomic energy are outlined and the impact of increasing instrumentation is discussed. Some recent developments in analytical chemistry instrumentation are reviewed and their possibilities and uses in the atomic energy field are assessed. These include automatic coulometry, square wave polarography, gamma spectrometry, low background beta counting, infra-red spectrometry, mass spectrometry, emission spectrography, X-ray spectrography and vacuum fusion analysis.
- ItemNeutron diffraction on HIFAR(Melbourne University Press on behalf of The Australian Atomic Energy Commission, 1958-06-02) Sabine, TMA brief account of the use of neutron diffraction as a complementary technique to X-ray diffraction in crystallographic analysis is given. The spectrometers to be installed on HIFAR are described and the experimental limitations of the technique discussed.
- ItemGas-cooled reactors of a mixed fuel-moderator type(Melbourne University Press on behalf of The Australian Atomic Energy Commission, 1958-06-02) Dalton, GCJReactors of this type may use any of the moderators, graphite, beryllium oxide or beryllium, and one of the coolant gases hydrogen, helium, carbon dioxide, nitrogen or other suitable gas to be selected on the grounds of compatibility with the moderator and circuit materials and engineering suitability. The uranium233-thorium fuel cycle is the most suitable because the conversion factor possible with this system is greater than with the Z plutonium-uranium238 cycle. Because there is no necessity for lumping the fuel, the moderator may be used to dilute the fuel and to increase the surface available for heat transfer to the coolant. This dilution should also improve the burn-up possible before the 6 fuel element suffers physical disintegration. The fuel and fertile material may be mixed uniformly with the moderator, or may be in a thin, enriched layer near the surface of the element. The fuel elements may be rods, spheres, plates, or bricks, pierced by coolant channels. Research will be directed towards the production of a high integrity fuel element, the solution of problems of compatibility of gas and moderator, control of fission products and reprocessing and refabricating fuel elements. It is expected that this type of reactor will have particular application in the power range of 5 to 5OMW.
- ItemThe development of radiochemical facilities at Lucas Heights(Melbourne University Press on behalf of The Australian Atomic Energy Commission, 1958-06-02) Miles, GL; Sangster, DFA description is given of the recently completed radiochemical laboratories at Lucas Heights. Design problems are discussed, as well as initial operating experience.
- ItemSome oxide ceramics as reactor materials(Melbourne University Press on behalf of The Australian Atomic Energy Commission, 1958-06-02) Reeve, KDAlthough the conventional advantages of ceramics lie in their favourable high temperature properties reactor technology has not yet made use of these properties, mainly because of their uncertain behaviour under irradiation. The fabrication and properties of beryllia, uranium dioxide and thoria, and of mixed oxide systems, are discussed.
- ItemAcid leaching and anode dissolution of graphite - moderated fuels(Melbourne University Press on behalf of The Australian Atomic Energy Commission, 1958-06-02) Hyde, KR; O'Connor, DJ; Woodhead, JLResults of nitric acid leaching and anodic disintegration processing studies of two types of homogeneous graphite moderated fuels ore reported. ZN nitric acid leaching at 90-100°C appears suitable as the primary processing method, whereby uranium and thorium are obtained in solution suitable for solvent extraction. Anodic disintegration in 2N nitric acid is a satisfactory wet method of breaking down the graphite fuel assemblies, but the disintegration process does not give the required uranium and thorium recoveries. lt has not been possible to assign any electrochemical action to the anodic solution of uranium and thorium carbides.
- ItemRadio-isotopes in Australian industry and research(Melbourne University Press on behalf of The Australian Atomic Energy Commission, 1958-06-02) Gregory, JNRadio-isotopes play a very prominent part in industry in the United States, the United Kingdom and other highly industrialised countries. These countries also use radio-isotopes, mainly as tracers, very extensively in basic and applied research, and in clinical medicine. Australian industry and research has been relatively slow to accept these new techniques, as illustrated by statistics in Table 1. The relatively low figure for the U.S.A. can be explained by their national policy in radioisotope production. In general, United States shipments from Oak Ridge are individually larger in quantity than the U.K. shipments. Many United States shipments are bulk supplies for commercial firms, who split them up for sale to the user in much smaller units. The United Kingdom organisations at Harwell and Amersham sell direct to the user, or in a form ready for use in almost all cases. Also, small shipments under general licence are not included in the U.S.A. data. If the U.S.A. figures were on the same basis as the United Kingdom data, the number of shipments per unit of population figure would be much larger than indicated in Table 1.
- ItemPossible developments in nuclear fuel cycles in Australia(Melbourne University Press on behalf of The Australian Atomic Energy Commission, 1958-06-02) Baxter, JP; Watson-Munro, CNThe need for nationally integrated nuclear fuel cycles is stressed and, based on a number of speculative assumptions, some calculations are made of the order of requirements of fissile and fertile material.
- ItemHeat transfer in homogeneous gas-cooled reactors(Melbourne University Press on behalf of The Australian Atomic Energy Commission, 1958-06-02) de Vahl Davis, GThe heat source distribution in a nuclear reactor is a function of neutron flux, fuel loading, and core temperature, each of which is a function of position. In certain types of solid fuel gas-cooled reactors, the fuel distribution is such that the reactor may be regarded as homogeneous. This paper describes the method of calculating the temperature distribution in the core of such a reactor. A cyclindrical core is assumed, and the variations of coolants flow and outlet temperature with radius are found. As a first approximation the dependence of neutron flux on temperature is taken to be small and the flux is assumed to have been calculated on the basis of uniform core temperature. using this flux distribution, the first core temperature distribution is found. Subsequent flux distributions can be calculated to refine the values of temperatures.
- ItemThe control and instrumentation of the reactor HIFAR(Melbourne University Press on behalf of The Australian Atomic Energy Commission, 1958-06-02) Page, GA brief description of the reacting core of HIFAR is given, together with some data on the reactivity balance. The principles of the coarse, fine and safety control systems are outlined. Mention is made of the various installed thermal neutron flux measuring channels. The electrical safety and interlock circuits and the ways in which they influence the operation of the reactor are discussed. An outline is given of the other associated instrumentation such as health monitors and general industrial instruments.
- ItemLiquid metal fuel reactors(Melbourne University Press on behalf of The Australian Atomic Energy Commission, 1958-06-02) Alder, KFThe advantages and disadvantages of a liquid metal fuel reactor system are outlined in relation to other possible power reactors. Liquid metals which are possible fuel carriers and coolants are discussed, and in particular a comparison is drawn between a solution-type fuel using bismuth and a dispersion-type using sodium. The reasons for the choice of a sodium dispersion fuel for the A.A..E.C. research project are presented and the problems posed by such a reactor system are summarised.
- ItemMaterials for the control of nuclear reactors(Melbourne University Press on behalf of The Australian Atomic Energy Commission, 1958-06-02) Wright, WJ; Nicholson, KPThe desirable properties of neutron absorbers are discussed, and the investments for the equivalent absorption in various materials are calculated. Physical and metallurgical limitations exist in the use of boron and cadmium, and the investment for blackness compared to burn-up in hafnium is unattractive. The rare earths, gadolinium, samarium and europium are discussed; dispersions of the oxides in steel are suggested for use as control elements in future high temperature reactors.
- ItemMeasurement of concentration of tungsten suspensions and density of liquid sodium by gamma ray absorption(Melbourne University Press on behalf of The Australian Atomic Energy Commission, 1958-06-02) Watt, JS; Lawther, JSGamma ray absorption techniques have been applied to measure the density of various media, and the theory of selecting the appropriate energy gamma ray to give optimum sensitivity of density determination for a homogeneous system is outlined. A gauge to determine the concentration of tungsten powder suspended in water in a concentration range of O to 8 gm. tungsten/c.c. suspension, has been developed. In this apparatus the mean tungsten concentration, 0.08 gm./c.c., can be measured to an accuracy of approximately +-0.0015gm./c.c. In the case of liquid sodium contained in o stainless steel vessel, preliminary experiments indicate that the density may be measured to an accuracy of +-0.01gm./ c.c. and that 0.01gm./c.c. transient changes in density occurring in a few seconds can be resolved.
- ItemThe philosophy and practice of radioactive waste disposal(Melbourne University Press on behalf of The Australian Atomic Energy Commission, 1958-06-02) Temple, RBThis general review is largely concerned with the problems of disposing of the large amounts of highly-radioactive waste that will result from a large-scale nuclear power program employing fission reactors. The dangers of dilution-dispersal are outlined, and particular attention is drawn to the possibility of biological reconcentration of the dispersed radioactivity. The conclusion is reached that it is imperative to find some method of permanently storing the activity in a non-leochable solid form, if the fullest use is to be made of nuclear power production. At present the "temporary expedient" of tank storage in liquid form is the only practicable method, but by I965 other methods will have to be found.
- ItemThe future of nuclear fuel reprocessing in Australia(Melbourne University Press on behalf of The Australian Atomic Energy Commission, 1958-06-02) Miles, GLAn attempt is made to predict the nature and scale of the nuclear fuel reprocessing industry which might be expected to develop in Australia up to about I975, and to indicate the kind of technical advances which will be required to achieve this.
- ItemThe HIFAR oscillator(Melbourne University Press on behalf of The Australian Atomic Energy Commission, 1958-06-02) Nicholson. KP; Pryor, AWA description is given of a pile oscillator which will enable thermal absorption cross-section measurements to be made on HIFAR. The apparatus is in course of construction. The principal design factors are discussed, with particular reference to the effects of scattering by the sample, and the extension of the range of cross-section measurements to include moderators such as graphite and beryllium.
- ItemThe design and construction of HIFAR(Melbourne University Press on behalf of The Australian Atomic Energy Commission, 1958-06-02) Roberts, WHA brief description is given of the design and construction Commission's of the Australian Atomic Energy reactor HIFAR, located near Sydney or Lucas Heights. The design is based on that of the British DIDO, a high flux, heavy water moderated and cooled reactor having a maximum thermal neutron flux of 1014 neutrons/sq. cm/sec., and a maximum heat output of l0 megawatts.
- ItemPilot plant development of processes for the production of nuclear grade uranium dioxide(Institution of Chemical Engineers, 1972-08-17) Alfredson, PGMost types of nuclear power reactors use fuel in the form of high density uranium dioxide pellets clad in Zircaloy. Sinterable uranium dioxide powder is usually produced via the ammonium diuranate (ADU) route. This involves dissolution of uranium ore concentrates (yellow cake) in nitric acid, purification by solvent extraction using tributyl phosphate in kerosene, precipitation of ADU, filtration, drying, calcination and reduction with hydrogen to give uranium dioxide powder. The Australian Atomic Energy Commission has carried out pilot plant development of these processes to demonstrate the production of nuclear grade uranium dioxide from Australian yellow cake and to improve the processes and technology wherever possible. This paper describes the processes and equipment with particular reference to the improvements which have been made. The nitric acid requirements in the solvent extraction process have been substantially reduced and a pulsed fluidised bed reactor has been developed for the continuous calcination-reduction of ADU to uranium dioxide. The influence of the conditions for precipitation of ADU on its rate of filtration and on the fabrication behaviour of the uranium dioxide powder is also described.
- ItemPractical problems associated with fracture-safe design for welding(Australian Welding Institute, The Institution of Engineers Australia, 1973-10-18) Quaass, STAn attempt is made to identify how practical problems arise in a large project, what these problems are, and possible ways of avoiding them. It is proposed that if certain critical technical requirements are compromised by other primary factors such as economics, scheduling, partisan interests etc. then it must be accepted that failures will continue to be experienced.
- ItemThe possible transmutation of radioactive waste from nuclear reactors(Australian Institute of Physics, 1974-05-21) Harries, JRA nuclear reactor power program produces high level long lived radio-active wastes. The high level activity is associated with fusion products, but beyond 400 years the principal waste hazard is from transuranic elements produced in the reactor. Several schemes have been proposed for the transmutation of the problem isotopes into more easily handled isotopes. The neutron flux in a thermal reactor is not high enough to significantly reduce the longer lived fission product isotopes 90Sr and 132Gs, but the transuranic elements can be reduced by recycling through power reactors. The limitation on recycling of the transuranic elements is the separation process to remove trace quantities from the wast stream. In fact reactors the transuranic elements are the principal fuel and fast reactor waste contains only half as much 90Sr as thermal reactors. However, the overall waste hazard is similar to thermal reactors. A sufficiently intense neutron flux for fission product transmutation could perhaps be produced by a spallation reactor driven by a proton linear accelerator or a controlled thermonuclear reactor. However, both concepts are still some years in the future. Transmutation by accelerator sources of protons, electron or gammas tend to require more energy than neutron transmutation.