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Moose Jaw, Canada

Rayne S.,Chemologica Research | Forest K.,Saskatchewan Polytechnic
Journal of Environmental Science and Health - Part A Toxic/Hazardous Substances and Environmental Engineering | Year: 2016

The SPARC software program was used to estimate the acid-catalyzed, neutral, and base-catalyzed hydrolysis rate constants for the polymeric brominated flame retardants BC-58 and FR-1025. Relatively rapid hydrolysis of BC-58, producing 2,4,6-tribromophenol—and ultimately tetrabromobisphenol A—as the hydrolytically stable end products from all potential hydrolysis reactions, is expected in both environmental and biological systems with starting material hydrolytic half-lives (t1/2,hydr) ranging from less than 1 h in marine systems, several hours in cellular environments, and up to several weeks in slightly acid fresh waters. Hydrolysis of FR-1025 to give 2,3,4,5,6-pentabromobenzyl alcohol is expected to be slower (t1/2,hydr less than 0.5 years in marine systems up to several years in fresh waters) than BC-58, but is also expected to occur at rates that will contribute significantly to environmental and in vivo loadings of this compound. © 2016 Taylor & Francis Group, LLC Source


Maddison T.,Saskatchewan Polytechnic
Issues in Science and Technology Librarianship | Year: 2015

This case study explores the use of flipped teaching in three different undergraduate engineering courses, discussing the advantages and disadvantages of class size and how it affects the delivery of information literacy instruction as observed through student engagement and the perceived helpfulness of the instruction. A flipped classroom was used in three separate engineering design classes during the 2014-15 academic school calendar. Two of these classes were offered in a computer lab to less than 30 students (one class was divided into sections for ease of instructional delivery) and one was offered to a large class in a lecture format without the availability of computers for each student. The flipped components relied on online video tutorials that were posted on YouTube and then embedded in the library guides for the discipline. This paper provides the results from an analysis of page views alongside usage statistics from YouTube. Both of these sources of information along with post-test results provided useful data in determining the effectiveness of flipped teaching in both a large lecture format and a smaller computer lab setting. The highest engagement scores were seen from the classes taught in a computer lab. © 2015, Association of College and Research Libraries. All rights reserved. Source


Rayne S.,Chemologica Research | Forest K.,Saskatchewan Polytechnic
Science of the Total Environment | Year: 2016

Annual and summertime trends towards increasingly variable values of the Palmer Drought Severity Index (PDSI) over a sub-decadal period (five years) were investigated within the contiguous United States between 1895 and the present. For the contiguous United States as a whole, there is a significant increasing trend in the five-year running minimum-maximum ranges for the annual PDSI (aPDSI5yr(min|max, range)). During this time frame, the average aPDSI5yr(min|max, range) has increased by about one full unit, indicating a substantial increase in drought variability over short time scales across the United States. The end members of the running aPDSI5yr(min|max, range) highlight even more rapid changes in the drought index variability within the past 120years. This increasing variability in the aPDSI5yr(min|max, range) is driven primarily by changes taking place in the Pacific and Atlantic Ocean coastal climate regions, climate regions which collectively comprise one-third the area of the contiguous United States. Similar trends were found for the annual and summertime Palmer Hydrological Drought Index (PHDI), the Palmer Modified Drought Index (PMDI), and the Palmer Z Index (PZI). Overall, interannual drought patterns in the contiguous United States are becoming more extreme and difficult to predict, posing a challenge to agricultural and other water-resource related planning efforts. © 2015 Elsevier B.V. Source


Rayne S.,Chemologica Research | Forest K.,Saskatchewan Polytechnic
Journal of Environmental Science and Health - Part A Toxic/Hazardous Substances and Environmental Engineering | Year: 2016

The air–water partition coefficients (Kaw) for 86 large polycyclic aromatic hydrocarbons and their unsaturated relatives were estimated using high-level G4(MP2) gas and aqueous phase calculations with the SMD, IEFPCM-UFF, and CPCM solvation models. An extensive method validation effort was undertaken which involved confirming that, via comparisons to experimental enthalpies of formation, gas-phase energies at the G4(MP2) level for the compounds of interest were at or near thermochemical accuracy. Investigations of the three solvation models using a range of neutral and ionic compounds suggested that while no clear preferential solvation model could be chosen in advance for accurate Kaw estimates of the target compounds, the employment of increasingly higher levels of theory would result in lower Kaw errors. Subsequent calculations on the polycyclic aromatic and unsaturated hydrocarbons at the G4(MP2) level revealed excellent agreement for the IEFPCM-UFF and CPCM models against limited available experimental data. The IEFPCM-UFF-G4(MP2) and CPCM-G4(MP2) solvation energy calculation approaches are anticipated to give Kaw estimates within typical experimental ranges, each having general Kaw errors of less than 0.5 log10 units. When applied to other large organic compounds, the method should allow development of a broad and reliable Kaw database for multimedia environmental modeling efforts on various contaminants. © 2016 Taylor & Francis Group, LLC Source


Rayne S.,Chemologica Research | Forest K.,Saskatchewan Polytechnic
Journal of Environmental Science and Health - Part A Toxic/Hazardous Substances and Environmental Engineering | Year: 2016

In order to estimate isomer-specific acidity constants (pKa) for the perfluorinated sulfonic acid (PFSA) environmental contaminants, the parameterization method 6 (PM6) pKa prediction method was extensively validated against a wide range of carbon oxyacids and related sulfonic/sulfinic acids. Excellent pKa prediction performance was observed for the carbon oxyacids using the PM6 method, but this approach was found to have a severe positive bias for sulfonic/sulfinic acids. To overcome this obstacle, a correlation was developed between non-adjusted PM6 pKa values and the corresponding experimentally obtained/estimated acidity constants for a range of representative alkyl, aryl and halogen-substituted sulfonic acids. Application of this correction to the PM6 values allows for extension of this computational method to a new acid functional group. When used to estimate isomer-specific pKa values for the C1 through C8 PFSAs, the modified PM6 approach suggests an adjusted pKa range from −5.3 to −9.0, indicating that all members of this class of well-known environmental contaminants will be effectively completely dissociated in aquatic systems. © 2016 Taylor & Francis Group, LLC Source

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