Department of Physics (Fredericton)

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Perturbed gamma-ray directional correlation studies on Ba II in aqueous solution
Perturbed gamma-ray directional correlation studies on Ba II in aqueous solution
by D. C. Sinclair, Directional correlation of 60Co was studied. A graph of the normalized coincidence rate versus the angle between the two gamma-rays was made as well as determining the A2 and A4 values. These exercises were mainly for familiarization with the apparatus. Perturbations of gamma-rays emitted after electron capture by 133Ba in aqueous solution were studied in the pH range of 1.5 to 13. At low Ba concentration, the directional correlation pattern was found to be essentially unperturbed over this pH range.
Perturbed gamma-ray directional correlation studies on Hafnium-181 in aqueous solution
Perturbed gamma-ray directional correlation studies on Hafnium-181 in aqueous solution
by Edward D. O’Reilly, The directional correlation of hafnium-181 was studied. Area of concern was the perturbation of the directionally correlated gamma ray emission pattern of ha.fnii.im-181 in aqueous solutions whose pH ranged from less than 1 to more than 14. Graphs of the perturbation factor [G2 (T) ] versus time [in nanoseconds] were made and the time averaged perturbation factors were calculated. For very acidic and very basic solutions, the perturbation was found to decrease exponentially with time. For solutions having intermediate pH values, the perturbation curve was found to asymptotically approach a set value of G2 (T) [=0.20] after an initial sharp drop.
Perturbed gamma-ray directional correlation studies on several barium salts
Perturbed gamma-ray directional correlation studies on several barium salts
by Pierre B. Therrien, On several Barium salts time dependent perturbed correlations studies were conducted and the preparation of a sample of Barium in a Gallium crystal lattice was unsuccessfully attempted. Perturbations were observed for samples of Barium chloride, Barium hydroxide, and Barium sulphate. The unperturbed case was first studied while the preparation of a Barium-Gallium sample was being attempted. The G2 for the Barium chloride and Barium hydroxide showed a strong perturbation compared to the Barium sulphate. The G2(t) for Barium salts indicated the presence of a perturbati9n but the detailed structure was not resolved., Page 39 is followed by pages A1-A10
Phenomenological theory of domain structures in quartz
Phenomenological theory of domain structures in quartz
by Christoph B. Grein, A phenomenological theory of the incommensurate phase of quartz is presented. The theory is based on the Ginzburg-Landau free energy density expansion. Both analytic and numerical methods are used to model one and two dimensional domain structures. Of particular significance with the one dimensional theory is the prediction of the rippled commensurate state. The two dimensional theory models the domain size, experimental presented, shape and orientation in agreement with results. Phase diagrams for quartz are presented.
Proton spin relaxation study of methanol absorbed on cellulose
Proton spin relaxation study of methanol absorbed on cellulose
by Michael J. Lesiak, The proton NMR relaxation times T1, T1p and T2 have been measured as a function of temperature between 383 K and 133 K for cellulose saturated with methanol. The resonance frequency was 30 MHz and the spin locking field pulse strength used to measure T1p was 10 Gauss. T1 shows a single component at all temperatures. T1p displays two components and T2 displays three components. The three components are attributed to protons on the cellulose molecule, protons on methanol molecules hydrogen bonded at the OH sites of the cellulose and protons on methanol molecules hydrogen bonded at the CH 20H sites of the cellulose. The temperature dependence of T1 is consistent with relaxation dominated by reorientation of the CH 3 group of the methanol molecules, with a broad distribution of correlation times.
Response of a Hard Spring Oscillator to narrow band random excitation
Response of a Hard Spring Oscillator to narrow band random excitation
by Dennis Nandlall, This Thesis Project has two main objectives: First, to develop a frequency response equation for narrow band random excitation of a nonlinear Hard Spring Oscillator from a statistical point of view and then make a comparison to the already known sinusoidal case. Secondly, the frequency response equation develop is analysed by varying the excitation bandwidth and the excitation force. Numerical results are obtained and frequency response curves are plotted and analysed.
Sand wave theory
Sand wave theory
by Norman Donaldson, Four unnumbered pages before the first numbered page
Seasonal variations of the interplanetary magnetic field Y component
Seasonal variations of the interplanetary magnetic field Y component
by Christine Lesiak, The Y component of the interplanetary magnetic field (IMF) undergoes a polarity change as an observer undergoes a sector boundary crossing. Interplanetary magnetic field data Y component data from the years 1964 to 1990 is examined to determine the average position of the earth relative to the heliospheric current sheet, and thus find any seasonal variations in its position. The polarity reversal of the By IMF is put in context of the sunspot cycle., Abstract numbered A1-A10, B1-B9
Second derivative least squares method
Second derivative least squares method
by Chris Boone, After final numbered page, appendix is numbered A1-A10, B1-B10 and C1-C10
Single bubble sonoluminescence: bubble dynamics and countering gravity
Single bubble sonoluminescence: bubble dynamics and countering gravity
by Borko Djurkovic, When bubbles suspended in a fluid are exposed to high frequency sound pressure, they begin to glow through emission of light. This phenomenon is termed sonoluminescence. The study of a single light emitting bubble, known as Single Bubble Sonoluminescence (SBSL), can provide us with a. better and more controlled method to study sonoluminescence in an attempt to explain many of its interesting and unique characteristics. To produce SBSL, a sinusoidal ultrasound signal is applied to a water-filled flask at its resonant frequency. The pressure gradient across the bubble forces it towards the pressure antinode. The bubble undergoes nonlinear radial oscillations caused by the pressure swings of the acoustic field. During the compression phase, the bubble experiences violent collapse which results in an emission of light with spectrum that is continuous into the ultraviolet region. The maximum of the spectrum is still unknown due to the absorption of light by water in this spectral region. In our previous work, we have discovered that by introducing a sinusoidal modulation to the amplitude of the acoustic signal, it is possible to control the bubble motion. In first part of this research, we present numerical models that try to simulate the bubble dynamics. In second part we try to develop a. mechanism for balancing the gravitational acceleration in a laboratory environment. A possible solution is to use a. magnetic field gradient to counteract the buoyancy force. A difficulty with this approach is that it requires large magnetic field gradients. However, it is possible to compensate for this by adding compounds to water that will alter its molecular susceptibility.

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