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Roogtanakait, N.

Department of Nuclear Technology, Chulalongkorn Univ., Bangkok (Thailand)

Department of Nuclear Technology, Chulalongkorn Univ., Bangkok (Thailand)

AbstractAbstract

[en] Gamma rays have high penetration power and its attenuation depends upon the thickness and the attenuation coefficient of the shield, so it is necessary to use the high density shield to attenuate the gamma rays. Heavy concrete is considered to be used for high radiation laboratory and the testing of the shielding ability and compressibility of various types of heavy concrete composed of baryte, hematite, ilmenite and galena is carried out. The results of this study show that baryte-ilmenite concrete is the most suitable for high radiation laboratory in Thailand

Primary Subject

Source

1981; 103 p; Chulalongkorn Univ; Bangkok (Thailand); Available from Graduate School, Chulalongkorn Univ., Bangkok (TH); Thesis (Master Eng.)

Record Type

Miscellaneous

Literature Type

Thesis/Dissertation; Numerical Data

Country of publication

Publication YearPublication Year

Reference NumberReference Number

INIS VolumeINIS Volume

INIS IssueINIS Issue

Milinthanggoon, N.

Department of Nuclear Technology, Chulalongkorn Univ., Bangkok (Thailand)

Department of Nuclear Technology, Chulalongkorn Univ., Bangkok (Thailand)

AbstractAbstract

[en] In Operating a nuclear power plant, especially the boiling light water reactor type, the radioactive fission products, especially Xenon and Krypton gases may leak out of fuel rods into the cooling water. Water removes heat from the reactor core and becomes steam which is used to generate electricity. These gases can be disposed of by allowing them to decay since they do not combine with other substances. During the decay process some isotopes having long half-life are inevitably released to the atmosphere. The diffusion of these radioactive gases is affected by atmospheric conditions. To prevent their concentration in air from exceeding the safety limit, it is necessary to study their distribution at different weather conditions. The analysis, using Fick ian Diffusion Equation, takes into account the amount of the radioactive gases release, safety limit and the height above ground at which each weather state exists. The result of the study will predict the radioactive gases concentration over the ground at various distances. From this study, it can be seen that when height increases the gases will disperse more easily. As a result the concentration over the area where the radioactive gases spread is lower. By means of stack the radioactive gases can be released at the height required. However, the minimum height shall be such that the concentration of the radioactive gases at the ground level is not hazardous. From the mathematical model used in this study, it is found that the stack of the nuclear power plant situated at Ao Pai should have a height not less than 65 meters

Primary Subject

Source

1977; 96 p; Chulalongkorn Univ; Bangkok (Thailand); Available from Graduate School, Chulalongkorn Univ., Bangkok (TH); Thesis (Master Eng.)

Record Type

Miscellaneous

Literature Type

Thesis/Dissertation; Numerical Data

Country of publication

Publication YearPublication Year

Reference NumberReference Number

INIS VolumeINIS Volume

INIS IssueINIS Issue

Nimnual, S.

Department of Nuclear Technology, Chulalongkorn Univ., Bangkok (Thailand)

Department of Nuclear Technology, Chulalongkorn Univ., Bangkok (Thailand)

AbstractAbstract

[en] An experiment was made to measure the dose from a short burst of X-rays in the order of 1 second or less by means of the cadmium sulphide photoconductive cell. If protected from light, the CdS cell has a very high resistance such that it does not discharge a capacitor appreciably. But during irradiation, the resistance decreases temporarily and an amount of charge will leak from the capacitor through the Ca S cell. The result to this experiment shows that the principle works very well but it is necessary to add another fixed high resistance of about 10

^{7}ohms into the circuit in order to get results independent of the dose-rate. The equipment used in this experiment can measure a dose as low as 6 m RSource

1975; 26 p; Chulalongkorn University; Bangkok (Thailand); Available from Graduate School, Chulalongkorn Univ., Bangkok (TH); Thesis (Master Eng.)

Record Type

Miscellaneous

Literature Type

Thesis/Dissertation; Numerical Data

Country of publication

Publication YearPublication Year

Reference NumberReference Number

INIS VolumeINIS Volume

INIS IssueINIS Issue

Spero, R.E.

California Univ., Irvine (USA)

California Univ., Irvine (USA)

AbstractAbstract

[en] A laboratory test of the inverse square law of gravity has been conducted. The almost null field inside a long precisely machined tube was probed by a test mass suspended from a torsion balance. In terms of a distance-dependent gravitational constant G(r), the experiment is sensitive to variations in G(r) over the distance range of approximately 2 to 5 cm. If G(r) = G

_{0}[1 + epsilon In r(cm)], epsilon is found to be (1 +- 7) x 10^{-5}, in support of the inverse square lawPrimary Subject

Source

1980; 139 p; University Microfilms Order No. 80-08,450; Thesis (Ph. D.).

Record Type

Report

Literature Type

Thesis/Dissertation; Numerical Data

Country of publication

Publication YearPublication Year

Reference NumberReference Number

INIS VolumeINIS Volume

INIS IssueINIS Issue

Panprommintra, C.

Department of Nuclear Technology, Chulalongkorn Univ., Bangkok (Thailand)

Department of Nuclear Technology, Chulalongkorn Univ., Bangkok (Thailand)

AbstractAbstract

[en] A nuclear reactor is a large source of radioactive substances. In the construction of a nuclear power plant, there must be the safety system to prevent hazards from radioactive substances. This thesis consists of a description of characteristics and the operation of the direct cycle boiling water reactor with safety system. The nuclear reactor is assumed to generate 600 megawatts of electricity and sited at Ao phai, Sri Racha. The site has been surveyed for population density in the surrounding area. The nuclear reactor is assumed to have a hypothetical accident from loss of coolant accident and releases some of fission products to the atmosphere. A calculation is made of the amount of radioactivity around the site within 20 kilometres and the dose which people will receive from hazardous radioactive substances such as I - 131, Volatile gases, Sr - 89, Sr - 90 and Cs - 137. The result of the calculation shows that in case of unfavorable atmospheric condition people will receive large dose at the border line of the exclusion area at 500 metres from the plant. But the risk at 500 metres from the nuclear power plant is much less than other risks

Primary Subject

Source

1977; 63 p; Chulalongkorn Univ; Bangkok (Thailand); Available from Graduate School, Chulalongkorn Univ., Bangkok (TH); Thesis (Master Eng.)

Record Type

Miscellaneous

Literature Type

Thesis/Dissertation; Numerical Data

Country of publication

Publication YearPublication Year

Reference NumberReference Number

INIS VolumeINIS Volume

INIS IssueINIS Issue

AbstractAbstract

[en] The integral energy method has been used in order to study the large-scale coherent wave mode interactions in a spatially developing round jet of a large Reynolds number. A flow quantity is split into two components; time-independent mean flow and large-scale coherent structure. The large-scale structure is decomposed into three fundamental wave modes (axisymmetric, first-order and second-order helical) and two subharmonic modes (axisymmetric and first-order helical). The streamwise development of a jet is obtained in terms of the mean flow shear layer momentum thickness, the wave mode kinetic energy and the wave mode phase angle. The results of the five mode interaction show that the axisymmetric and helical modes grow almost identically in the initial region until the energy densities of the fundamental modes reach peak values. When the initial energy density of one wave mode is much higher than those of the other modes, the other wave modes do not affect the streamwise development of the mean flow and the forced mode until the energy density of the forced mode reaches a peak value. The jet development also can be predicted by two wave modes (fundamental and subharmonic) if their initial energy densities are much higher than those of the others

Primary Subject

Secondary Subject

Source

1988; 311 p; Brown Univ; Providence, RI (USA); University Microfilms, PO Box 1764, Ann Arbor, MI 48106, Order No.88-22,548; Thesis (Ph. D.).

Record Type

Miscellaneous

Literature Type

Thesis/Dissertation; Numerical Data

Country of publication

Publication YearPublication Year

Reference NumberReference Number

INIS VolumeINIS Volume

INIS IssueINIS Issue

Porter, A.C.

California Inst. of Tech., Pasadena, CA (USA)

California Inst. of Tech., Pasadena, CA (USA)

AbstractAbstract

[en] This thesis presents ellipse-fitting isophotometry of 175 brightest elliptical galaxies in Abell clusters (BDEs). Galaxy structure is traced to an average major axis of 50 kpc, and sometimes beyond 100 kpc. The data consist not only of major and minor-axis surface brightness profiles, but also of isophote ellipticity, major axis position angle, and centroid position profiles. Almost all BCEs have some local structure that does not show in an azimuthally averaged brightness profile. However, local structure shows no correlation with global parameters such as galaxy luminosity or size. These results echo similar earlier findings for field ellipticals. An analytic method for separating the light distributions of overlapping binary galaxies has been derived and applied to 12 such systems. It is based solely on the assumption that each galaxy in the pair has point-reflection symmetry about its own center. Nonconcentric light is a probe of interactions between the members of the pair

Primary Subject

Secondary Subject

Source

1988; 472 p; California Institute of Technology; Pasadena, CA (USA); University Microfilms, PO Box 1764, Ann Arbor, MI 48106, Order No.88-20,983; Thesis (Ph. D.).

Record Type

Miscellaneous

Literature Type

Thesis/Dissertation; Numerical Data

Country of publication

Publication YearPublication Year

Reference NumberReference Number

INIS VolumeINIS Volume

INIS IssueINIS Issue

Karabali, D.

Yale Univ., New Haven, CT (USA)

Yale Univ., New Haven, CT (USA)

AbstractAbstract

[en] Certain nonperturbative phenomena appearing in two specific (2 + 1) dimensional models are studied. The phenomenon of fractional spin and exotic statistics in (2 + 1) dimensions is analyzed in the context of a specific field theoretic model, namely the (2 + 1) dimensional 0(3) nonlinear sigma model, with a topological action, the Hopf term. It admits solitons, which acquire fractional spin, due to the topological term in the action. Canonical quantization methods are used to determine the fractional spin in terms of the topological charge Q of the solitons and the coefficient Θ of the Hopf term. A semiclassical quantization in terms of collective coordinates in the Q = 1 sector is also carried out. The current algebra of the model is constructed and it is argued that the coefficient Θ can be understood as a parameter labeling different representations of the current algebra. The nonperturbative phenomenon of dynamical symmetry breaking is analyzed in the context of the (2 + 1) dimensional massless quantum electrodynamics with N species of fermions, treated in a 1/N expansion. The model exhibits a chiral symmetry which is spontaneously broken by dynamically generated fermion masses. The Dyson-Schwinger equations for the model are studied and it is shown that there exist symmetry breaking solutions

Primary Subject

Secondary Subject

Source

1986; 99 p; Yale Univ; New Haven, CT (USA); University Microfilms, PO Box 1764, Ann Arbor, MI 48106, Order No.87-28,146; Thesis (Ph. D.).

Record Type

Miscellaneous

Literature Type

Thesis/Dissertation; Numerical Data

Country of publication

Publication YearPublication Year

Reference NumberReference Number

INIS VolumeINIS Volume

INIS IssueINIS Issue

AbstractAbstract

[en] The direct imaging channel of the Princeton CCD spectrometer has been used to obtain four-color broadband photometry of two distant clusters of galaxies. The observations have been made as part of a search for evidence of galactic evolution. Data reduction techniques have been developed to extract photometric information from small images of low surface brightness. These techniques have been applied to obtain broadband colors in the spectral range between 5000 and 9000 Angstroms down to a limiting apparent visual magnitude of about 21.5. The observed colors show no evidence for the presence of substantial numbers of young blue stars. There is some evidence for an anomalously broad distribution of color in the spectral range between 7000 and 9000 angstroms

Primary Subject

Source

1980; 142 p; University Microfilms Order No. 80-16,163; Thesis (Ph. D.).

Record Type

Report

Literature Type

Thesis/Dissertation; Numerical Data

Country of publication

Publication YearPublication Year

Reference NumberReference Number

INIS VolumeINIS Volume

INIS IssueINIS Issue

Farawila, Y.M.

Wisconsin Univ., Madison (USA)

Wisconsin Univ., Madison (USA)

AbstractAbstract

[en] The problem addressed in this thesis research is the accurate evaluation of neutron fluence-to-kerma (Kinetic Energy Released in Materials) factors from microscopic nuclear data. The algorithms developed for this purpose combine in a consistent manner the two basic methods for computing kerma factors, namely kinematics and direct energy balance. These algorithms are implemented in the code KAOS-V which was used as the main evaluation tool to construct the response function library KAOS/LIB-V. The library contains kerma factors and other nuclear response functions for 43 nonfissionable and 15 fissionable isotopes and elements. The chief source of data is the evaluated nuclear data files ENDF/B-V. Auxiliary nuclear data bases, e.g., the Japanese evaluated nuclear data library JENDL-2 were used as a source of isotopic cross sections when these data are not provided in ENDF/B-V files for a natural element. These are needed mainly to estimate average quantities such as effective Q-values for the natural element. This analysis of local energy disposition was instrumental in detecting and understanding energy-balance deficiencies and other problems in the ENDF/B-V data

Primary Subject

Source

1987; 227 p; University Microfilms Order No. 87-23,328; Thesis (Ph. D.).

Record Type

Report

Literature Type

Thesis/Dissertation; Numerical Data

Country of publication

Publication YearPublication Year

Reference NumberReference Number

INIS VolumeINIS Volume

INIS IssueINIS Issue

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