3 resultados para breakthrough

em Brock University, Canada


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Physics professors Frans Koffyberg (right), Fereidoon Razavi (middle), and Bozidar Mitrovic (left) discover a new superconductor. A superconductor is a material that conducts electricity at very low temperatures with zero electrical resistance. The Brock researchers found that a compound of the metals Barium, Lanthanum, Copper, and Oxygen become a superconductor at 30 degrees absolute, which is a record high temperature.

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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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and the Australian Country Party since 1918. 2. The thesis examines the proposition that the role of a minor party is determined, not by its total strength expressed as a percentage of the national vote, but by how its strength is concentrated. Australia and Britain were chosen for the comparison because of the many similarities in political culture and in the extent of class voting. Each country has a party - the Country Party in Australia and the Liberal Party in Britain - which has had a distinct impact on the political scene in their respective countries. In the period from 1918 to the present day neither party, at the national level, has ever held the largest number of seats in parliament let alone a majority of seats, and it is in this sense that they are herein defined as minor parties. In the thesis the constitutional background of and differences between Australia and Britain are reviewed, followed by a brief historical picture of each of the two parties being studied. The sources of supporc of the two parties are analysed and it is here that real differences emerge. The Country Party in Australia is a deliberately sectional party with a narrow rural base, whereas the British Liberal Party is more broadly based than either the Labour or Conservative Parties in Britain. 3. Party leadership and organisation are then discussed. Both parties have had outstanding leaders, Earle Page and McEwen for the Country Party; Asquith, Lloyd George and Grimond for the Liberal Party. Both parties have had relatively fewer leaders than their major party opponents. However, whereas the Country Party has been free of serious splits the Liberal Party was shattered on the leadership struggles of Asquith and Lloyd George. Both parties have been identified with decentralisation of state power, the Country Party through its support, albeit sometimes lukewarm of the New States Movement; the Liberal Party through its espousal of a federal system for Britain with separate Welsh, Scottish and regional assemblies. Unfortunately for the British Liberal Party the beneficiaries of their policies in this area have been relatively new nationalist parties in both Wales arid Scotland. The major part of the thesis is devoted to a study of how the electoral systems in the two countries have, in practice, worked to the advantage or disadvantage of the Country Party and the British Liberal Party. The Country Party has been as consistently over-represented in the House of Representatives as the Liberal Party has been under-represented in the British House of Commons. With the even distribution of its support the introduction of the single transferable vote, in itself, would bring little benefit to the British Liberal Party in terms of seats. Multimember urban constituencies combined with some type of list system are the only way the Liberals are likely to obtain House of Commons seats in proportion to their votes. 4. Finally, the relations of the two minor parties with their respective major parties are considered. In the conclusion the future of the two parties is reviewed. In general terms it appears that the Country Party is faced with a slow decline. Although the British Liberal Party made a major breakthrough, in terms of votes, in the February 1974 election, they were unable to maintain this momentum in the October election, even though they lost very little ground. In the long term they must make an inroad into Labour held seats if they are to progress further.