7 resultados para STANDARD AUTOMATED PERIMETRY

em Brock University, Canada


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Several automated reversed-phase HPLC methods have been developed to determine trace concentrations of carbamate pesticides (which are of concern in Ontario environmental samples) in water by utilizing two solid sorbent extraction techniques. One of the methods is known as on-line pre-concentration'. This technique involves passing 100 milliliters of sample water through a 3 cm pre-column, packed with 5 micron ODS sorbent, at flow rates varying from 5-10 mUmin. By the use of a valve apparatus, the HPLC system is then switched to a gradient mobile phase program consisting of acetonitrile and water. The analytes, Propoxur, Carbofuran, Carbaryl, Propham, Captan, Chloropropham, Barban, and Butylate, which are pre-concentrated on the pre-column, are eluted and separated on a 25 cm C-8 analytical column and determined by UV absorption at 220 nm. The total analytical time is 60 minutes, and the pre-column can be used repeatedly for the analysis of as many as thirty samples. The method is highly sensitive as 100 percent of the analytes present in the sample can be injected into the HPLC. No breakthrough of any of the analytes was observed and the minimum detectable concentrations range from 10 to 480 ng/L. The developed method is totally automated for the analysis of one sample. When the above mobile phase is modified with a buffer solution, Aminocarb, Benomyl, and its degradation product, MBC, can also be detected along with the above pesticides with baseline resolution for all of the analytes. The method can also be easily modified to determine Benomyl and MBC both as solute and as particulate matter. By using a commercially available solid phase extraction cartridge, in lieu of a pre-column, for the extraction and concentration of analytes, a completely automated method has been developed with the aid of the Waters Millilab Workstation. Sample water is loaded at 10 mL/min through a cartridge and the concentrated analytes are eluted from the sorbent with acetonitrile. The resulting eluate is blown-down under nitrogen, made up to volume with water, and injected into the HPLC. The total analytical time is 90 minutes. Fifty percent of the analytes present in the sample can be injected into the HPLC, and recoveries for the above eight pesticides ranged from 84 to 93 percent. The minimum detectable concentrations range from 20 to 960 ng/L. The developed method is totally automated for the analysis of up to thirty consecutive samples. The method has proven to be applicable to both purer water samples as well as untreated lake water samples.

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Bank stabilization structures are used to prevent the loss of valuable land within the urban environment and the decision for the type of structure used depends on the properties of the stream. In the urban areas of Southern Ontario there is a preference for the use of armourstone blocks as bank stabilization. The armourstone revetment is a free standing stone structure with large blocks of stone layered vertically and offset from one another. During fieldwork at Forty Mile Creek in Grimsby, Ontario armourstone failure was identified by the removal of two stones within one column from the wall. Since the footer stones were still in place, toe scour was eliminated as a cause of failure. Through theoretical, field, and experimental work the process of suction has been identified as a mode of failure for the armourstone wall and the process of suction works similarly to quarrying large blocks of rock off bedrock streambeds. The theory of lateral suction has previously not been taken into consideration for the design of these walls. The physical and hydraulic evidence found in the field and studied during experimental work indicate that the armourstone wall is vulnerable to the process of suction. The forces exerted by the flow and the resistance of the block determine the stability of the armourstone block within the wall. The design of the armourstone wall, high surface velocities, and short pulses of faster flowing water within the profile could contribute to armourstone failure by providing the forces needed for suction to occur, therefore adjustments to the design of the wall should be made in order to limit the effect.

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We provide an algorithm that automatically derives many provable theorems in the equational theory of allegories. This was accomplished by noticing properties of an existing decision algorithm that could be extended to provide a derivation in addition to a decision certificate. We also suggest improvements and corrections to previous research in order to motivate further work on a complete derivation mechanism. The results presented here are significant for those interested in relational theories, since we essentially have a subtheory where automatic proof-generation is possible. This is also relevant to program verification since relations are well-suited to describe the behaviour of computer programs. It is likely that extensions of the theory of allegories are also decidable and possibly suitable for further expansions of the algorithm presented here.

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The St. Catharines Standard started publication in 1891 under W.B. Burgoyne. It was subsequently purchased by Southam Newspapers, then Canwest Global Communications. Osprey Media took over the publication until June 1, 2007 when Quebecor acquired the company. The St. Catharines Standard celebrated its centennial in 1991 with mobile displays, a centennial logo and slogan, a Christmas card, an advertising campaign, a video and a centennial theme to regular promotions. As part of the activities, the Standard commissioned Brock University to produce a history of St. Catharines. This book entitled St. Catharines Canada’s Canal City is a popular book rather than an academic text. The authors have woven together stories of the past and present to showcase the character and personality of St. Catharines. The book is full of maps and photographs, many of which had not been seen in print before this time.

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A photograph and brief comment about the race results for Dorothy Rungeling. She is photographed next to George Belfry of Thompson Products (sponsor), Alice Little (co-pilot) and radio broadcaster Rex Stimers.

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The Daily Standard, St. Catharines, Ontario. This paper contains an advertisement for James D. Tait Company and H.K. Woodruff is listed under the article “The Voice of the People” as an elected member of the Water Commission and an alderman January 2, 1900.

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The St. Catharines Standard supplement featuring a Tribute to the Father of Transportation, the Honorable William Hamilton Merritt, November 28, 1974.