Resolution of the strong CP problem

It is shown that the quark mass aligns QCD $\theta$ vacuum in such a way that the strong CP is conserved, resolving the strong CP problem.Comment: 9 pages;v2 slightly rewritten and expanded;v3 a few points clarified;v4 minor changes, journal versio

The Struggle for Leadership in the African American Church

This study focuses on looking at the struggles that African American leaders have within the church setting. It analyses the failings of the church in its mandate to offer spiritual and social nourishment to the black community. There have been concerns by clergy and the community at large that the reverent position that the church leader is no longer present. In its place, lies frustration and, in some cases, anger. The study will unravel the cause of the descent of the church. It examines a plethora of literature on the area, finding both supporting and opposing information. In the methodology, the study uses a mixed approach that incorporates the use of quantitative questionnaires in addition to intervention design. The results of this process indicate that the leaders are not aware of the issues facing their church. The dominance of power reduced inclination towards altruism and service leadership, diminished engagement with church congregants, poor planning for ministerial strategy, and lack of communication come of the leading problems in churches. The study thus recommends open dialogue on how to strengthen the church, especially within the younger generation, to encourage austerity of the black church. Further research can look at the shifting identity of black people and how it has affected the perceptions of the church

CONTROL OF GRAIN STRUCTURE IN SELECTIVE-ELECTRON BEAM MELTING OF NICKEL-BASED SUPERALLOYS

The powder bed additive manufacturing process of selective-electron beam melting can produce near net shape parts with nickel based superalloys. Control of grain structure is the next step in research as site specific columnar or equiaxed grain structure can give the process further advantage over traditional processing. Previous work has used alloys that were designed for casting processes and have not tried to control the columnar to equiaxed transition (CET) by changing the composition. To determine if alloying for the CET is possible, two custom high gamma prime nickel alloys were designed using CALPHAD software and a CET model. After processing the custom alloys alongside traditional alloys using the Selective Electron Beam Melting (S-EBM) process multi-scale characterization was performed to determine the resulting grain and precipitate structure. From our findings, the process parameters and class of alloy have more control over the CET than expected. Alloying for the CET, without the context of final geometry and processing, is not recommended due to composition having a greater effect on precipitant structure than grain structure

Operational Characteristics of a Fission Gas Detector

Introduction: One of the major problems associated with the operation of nuclear reactors is the radioactivity hazard caused by the release of fission products from the fuel. In a solid-fuel reactor, the uranium is usually present in an allow or in the form of UO2, either in the pure state or mixed with other oxides which improve the thermal and mechanical properties of the material. As the fuel material undergoes fission in the reactor, radioactive fission products are produced. If they were not prevented from doing so, these fission products would diffuse out of the fuel material, enter the reactor coolant as it flows past the fuel, and be carried from the reactor. The magnitude of the hazard thus created depends on the type of reactor, the reactor power, shielding of the coolant lines, and other factors. In a reactor where the coolant makes only a single pass through the system, such as the air-cooled the graphite reactors, the fission products are discharged into the atmosphere or into some coolant sink. This situation is usually unacceptable from a health standpoint. If the coolant flows in a closed loop, as in most present day water-cooled reactors, the fission products build up in the coolant, producing a radiation hazard in the coolant loop

Life-Cycle Cost Effectiveness and Safety Evaluation Involving Tennessee Bureau of Investigation Vehicles

The purpose of this study was to identify and analyze the life-cycle effectiveness and safety factors involved in operating Tennessee Bureau of Investigation (TBI) motor vehicles from zero miles through life-cycle. The major concerns were to provide a balance of economic and safety factors for determining when vehicles should be replaced. The data were collected from TBI files, Department of Transportation (DOT) records, and the National Automobile Dealers Associations Guide (NADA). The analysis consisted of entering the data into a computer where they were cross tabulated to determine the correlation between operational costs and mileage. The major findings of the research were that economic savings could be achieved if TBI vehicles were traded at 85,000 miles as opposed to trading same vehicle at seventy thousand miles and that operating TBI vehicles past seventy thousand miles did not create safety hazards. A nomograph was utilized for determining when vehicles should be replaced. The three major conclusions were based on the findings: 1. TBI vehicles, if traded at 85,000 miles instead of 70,000 miles would create economic savings for the organization; 2. The operation of TBI vehicles past seventy thousand miles does not create safety hazards; and miles apparently have no bearing in terms of safety: 3. If the procedure for determining the life-cycle or replacement of TBI vehicles was instituted, economic savings could be recognized

Effects Of Industrial Effluents On Populations Of The Freshwater Mussel Lampsilis Radiata In The St Lawrence River

The objective of this study was to assess the effects of industrial discharges, contaminated primarily with trace metals, on populations of Lampsilis radiata (Bivalvia: Unionidae) in the upper St. Lawrence River. Effects on shell growth were examined by (a) comparing growth curves derived from analyses of external annual rings of clams sampled from sites located upstream and downstream of four localized sources of discharges, and (b) measuring shell growth for one year from clams that were transplanted into contaminated and uncontaminated sites. Allozyme frequencies in clams from above and below discharges were determined for glucose-phosphate isomerase (GPI) and phosphoglucomutase (PGM), two enzyme systems reported to be sensitive to selection by polluted conditions. Field collected clams and sediment were analysed for trace metal content to correlate soft tissue burdens with degree of environmental contamination. Toxicity tests with glochidia larvae were performed with zinc to test for differential resistance based on the source (upstream versus downstream of a zinc-enriched discharge), and the GPI and PGM genotypes of the mother clams.;Minor depressions were detected in shell growth patterns of clams from downstream of discharges relative to clams from upstream in three out of four discharge areas. However, no shell growth depression was observed in clams transplanted into contaminated sites. Shell growth of transplanted clams was strongly affected by their collection source, suggesting that genetic factors or irreversible physiological compensation is more important in controlling shell growth than environmental contaminants. There was no evidence for differential selection of allozymes in clams from upstream and downstream of discharges. Metal burdens were elevated in clam tissue only in those from the most polluted site. Although glochidia of clams from polluted and unpolluted sites exhibited significant among-clam variability in resistance to zinc toxicity, differences were not related to source (site) or genotype of mother clams.;These results suggest that populations of L. radiata in the upper St. Lawrence River are either resilient to effects of industrial discharges, or that gene flow between sites is sufficiently high to offset selective pressure by contaminants