Chess Whiz to Take on All Comers at UM

David Ross, No. 1 player in Mississippi, will play the first 25 contestants who sign u

Study program to obtain the infrared internal reflection spectra of powdered rocks Final report

Internal reflection spectroscopy of powdered quartz fraction

Passion for Dance, Philanthropy Drives CASA Encore Performer

Mackenzie Jordan, a member of Kappa Kappa Gamma\u27s dance team, relishes giving bac

Modeling of the reciprocating, pneumatic impact hammer

The motion of the reciprocating, pneumatic impact tool, the air-driven piston inside the tool, the chisel mounted into the tool, and the specifically designed single degree-of-freedom spring-damper-mass test fixture were modeled with a MATLAB computer code. The three tools modeled and evaluated experimentally were the Ingersoll-Rand IR-121 impact tool, the Sears Craftsman Medium Duty impact tool, and the ATSCO No.2 impact tool; The computer model of the accelerations of the tool and the test fixture mass were compared to the experimental data obtained on the actual test fixture by the three tools modeled. The correlation between the experimental data and the modeled data is high in both the time domain and the frequency domain; The computer model is modified to include an air spring vibration attenuation mechanism. The model is used to tune the attenuation device as well as predict the force produced by the chisel into the work piece and the vibration through the tool into the hand-arm of the operator. The computer program allows other attenuation methods to be modeled and evaluated prior to actual construction

Comicana Explores Broad Range of Real-World Issues

Weeklong UM event focuses on the role of comics and graphic novels in exploring weighty subject

Lambda Sigma Honor Society Recognized for Giving Back

Partnership with Ole Miss Food Bank leads to national award for honorar

Thermal and Magnetic Studies of Spin Ice Compounds

In recent years a great deal of interest has been attracted by the materials called ‘spin ices’, and the monopole-like quasiparticle excitations inside them. Spin ices are frustrated Ising ferromagnets with a high level of frustration arising from a spin configuration akin to the proton configuration of water ice. Excitations of the ground state configurations can produce local arrangements of spins which behave similarly to magnetic monopoles, including carrying an effective magnetic charge and experiencing Coulomb interactions with one another. By taking these ‘monopoles’ as the units of analysis, theories of charged particle interaction can be applied to magnetic spin ice crystals. This thesis will examine the applicability of a number of theories based on this model to experimental data of the real properties of spin ice, along with a novel ex-perimental method, and in turn report on what the results suggest about the phys¬ical nature of the spin ices in question. The main materials studied are dysprosium titanate (Dy2Ti2O7) and holmium titanate (Ho2Ti2O7), and additional investiga¬tions are performed on cadmium erbium selenide (CdEr2Se4) and praseodymium zirconate (Pr2Zr2O7). First, a new derivation of the Debye-H¨uckel theory of electrolytes adapted for spin ice is presented, incorporating a microscopically correct partition function and the effects of higher-energy excitations, called ‘double monopoles’. The theory is compared to specific heat experimental and simulation data for Ho2Ti2O7 and Dy2Ti2O7 and experimental data for CdEr2Se4. It is found that Debye-H¨uckel theory is an effective analytic theory of spin ice magnetic heat capacity even into high temperatures of 6 K or more, in contrast to earlier work which held that such temperatures are out of the effective region of the spin ice model. Extensions of the theory to account for lattice geometry, Bjerrum pairing and ‘entropic charge’ are considered. Second, several theories for describing the magnetic relaxation of spin ice are compared to experimental data from Dy2Ti2O7 at 0.4 to 0.6 K. The theories encompass the Wien effect seen in electrolytes, surface effects and the failure of the samples to equilibrate on experimental timescales. The results are inconclusive and suggest that multiple effects must be considered to form a complete theory of spin ice relaxation at low temperatures. Third, an absolute measurement of the entropy of the quantum spin ice Pr2Zr2O7 using a recently introduced method is reported and compared to previous work on the material, along with a prediction of its specific heat using Debye-H¨uckel theory. The results demonstrate that the method is effective at low temperatures and suggest that the low-temperature entropy of Pr2Zr2O7 is less than that of classical spin ices, and that its monopole dynamics are significantly different

North Atlantic ocean circulation and the onset of Northern Hemisphere glaciation

Since the early Cenozoic, the Earth’s climate has been gradually cooling. Large ice sheets have expanded on several occasions in the past 5000 kyr (50 Ma), with the last major expansion being the onset of major ice sheets in the Northern Hemisphere between 3600 and 2500 ka. This period was characterised by a prolonged increase in ice volume, modulated by orbital forcing. At the same time, major tectonic changes were taking place, with the closure of the Central American Seaway most significant. This thesis aims to address the issue of what caused the onset of major Northern Hemisphere glaciation through an in depth study of samples from North Atlantic ODP Site 982 (57° 31’ N, 15° 51’ W; 1145 m water depth). Multi-species benthic foraminifera composite trace metal records (Mg/Ca, B/Ca, Li/Ca, Cd/Ca) were produced, and the composite Mg/Ca record was used to develop a new regional temperature calibration for the Pliocene. Paleoceanographic records of bottom water temperature and saturation state were produced, as well as bottom water flow speed records using the Sortable Silt (SS) proxy. Bottom water temperature (BWT) records showed an abrupt, ~2°C cooling at 2800-2700 ka, consistent with other previously published records. These data are combined with previously published benthic stable isotope (δ18Ob) records to reconstruct seawater oxygen isotope reconstructions (δ18Osw) across the period of study, and this is found to predominately reflect changes in global ice volume. A major and prolonged increase in ice volume (3500-3000 ka) is identified, equivalent to up to ~55m sea level decrease. The response of the North Atlantic region to this ice sheet growth was tested using previously published sea surface temperature (SST) and δ18Ob records from ODP Site 982, in addition to the new record from this study. The ice volume was found to have influenced the response of SST, δ18Ob, and SS to orbital forcing from changing insolation. Prior to the ice sheet growth, bottom water flow speed varied proportionally with sea surface temperatures, with increased deep water formation during periods of high seasonality. The growing ice sheets responded more slowly to insolation changes, and the presence of this ice sheet increased deep water formation by further cooling saline surface waters. This resulted in feedback loops that intensified deep water flow, leading to a significant increase in North Atlantic Deep water penetration to the southern ocean. A major decrease in δ18Osw at 2800-2700 ka was interpreted as either a loss of Antarctic ice mass, or a reorganization of North Atlantic water masses. Comparison of ice volume records with orbital spectra and reconstructions of the closure of the Central American Seaway suggest the immediate cause of Northern Hemisphere glaciation was a period of orbital conditions favourable to ice sheet growth. Another underlying cause was a series of tectonic shifts, including the closure of the Central American Seaway from 4200 ka, which changed heat and moisture transport patterns to the high latitudes

East Kent Gypsy and Traveller Accommodation Assessment Report (2007-2012)

1.0 Aims of the Study 1.1 De Montfort University and partners were commissioned in February 2007, by the four East Kent local authorities (Canterbury City Council, Dover District Council, Shepway District Council, and Thanet District Council), to undertake a Gypsy and Traveller Accommodation Assessment (GTAA). 1.2 The aim of the GTAA was to assess the accommodation needs of Gypsies and Travellers in the sub-region from 2007 – 2011; and then from 2012 – 2017. As required by the Communities and Local Government (CLG) guidance on GTAAs (February 2006), pitch requirements are given for permanent site and transit site provision. 1.3 The results of the East Kent GTAA are to be fed into the South East Regional Planning Body, pitch numbers will then be checked by the South East England Regional Assembly (SEERA) and modified to reflect the regional picture, and then pitch requirements will be given to each local planning body