21 resultados para invention


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This small tintype features a young Black woman standing in front of a painted backdrop with a large stone in the foreground at the studio of an unknown photographer. The unidentified woman is wearing a hat and holding a round fan. This black and white tintype was in the possession of Iris Sloman Bell, of St. Catharines, Ontario. Relatives of the Bell - Sloman families are former slaves from the United States who settled in Canada."Tintypes were the invention of Prof. Hamilton Smith of Ohio. They begin as thin sheets of iron, covered with a layer of black paint. This serves as the base for the same iodized collodion coating and silver nitrate bath used in the ambrotype process. First made in 1856, millions were produced well into the twentieth century. When tintypes were finished in the same sorts of mats and cases used for ambrotypes, it can be almost impossible to distinguish which process was used without removing the image to examine the substrate."

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An unidentified young Black gentleman poses beside a chair in this small tintype photograph. Both the name of the photographer and the date the photo was taken are unknown. The upper and lower left-hand corners have been cut and the tintype is slightly discolored and bent. This tintype was among the family memorabilia in the possession of Iris Sloman Bell, of St. Catharines, Ontario. The Bell - Sloman families are descended from former slaves from the United States."Tintypes were the invention of Prof. Hamilton Smith of Ohio. They begin as thin sheets of iron, covered with a layer of black paint. This serves as the base for the same iodized collodion coating and silver nitrate bath used in the ambrotype process. First made in 1856, millions were produced well into the twentieth century. When tintypes were finished in the same sorts of mats and cases used for ambrotypes, it can be almost impossible to distinguish which process was used without removing the image to examine the substrate." Source: American Museum of Photography http://www.photographymuseum.com/primer.html

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This undated small black and white tintype, slightly scratched, discolored and bent with age, shows a group of Black men posing for an unknown photographer. There is handwritten signature scratched into the reverse which appears to read "B.J." and "Owen" (see digital image of reverse). The original also has a hand-drawn "X" over the face of the seated man in the middle. This tintype was in the possession of Iris Sloman Bell, of St. Catharines, Ontario. The Sloman - Bell family descendants include former American slaves who settled in Canada."Tintypes were the invention of Prof. Hamilton Smith of Ohio. They begin as thin sheets of iron, covered with a layer of black paint. This serves as the base for the same iodized collodion coating and silver nitrate bath used in the ambrotype process. First made in 1856, millions were produced well into the twentieth century. When tintypes were finished in the same sorts of mats and cases used for ambrotypes, it can be almost impossible to distinguish which process was used without removing the image to examine the substrate." Source: American Museum of Photography http://www.photographymuseum.com/primer.html

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The natural abundance of the N-heterocycle containing compounds has pushed the synthetic community toward the invention of new synthetic methods that result in the structural diversity of N-heterocycles. Among this, is the efficient and highly selective diamine mediated asymmetric lithiation process. Amongst the diamine chiral ligands, (-)-sparterine, which is a naturally occurring alkaloid proved to be an efficient one. Many successful, good yielding and highly selective lithiation reactions have been accomplished with the mediation by this chiral diamine base. Although, there are some examples of experimental and theoretical mechanistic studies in the literature, there is a lack of detailed understanding as to how it exactly induces the chirality. In this thesis is described a systematic investigation of how (-)-sparteine influences the stereoselectivity in the course of asymmetric lithiation reaction. This led us to the establishment of the function of A-ring’s β-CH2 effect and D-ring effect. Consequently, the importance of the A-ring and D-ring portions of (-)-sparteine in the stereoselectivity is unraveled. Another part of this thesis deals with the asymmetric lithiation of BF3-activated N,N- dimethylaminoferrocene in the presence of (1R, 2R)-N1,N2-bis(3,3-dimethylbutyl)-N1,N2-dimethylcyclohexane-1,2-diamine ( a (R,R)-TMCDA surrogate) with i-PrLi. Computational findings were in full accord with the experimental observations. Subsequently, the theoretically provided insights into the mechanism of the reaction were exploited in computational design of a new ligand. Unfortunately, the outcome of this design was not experimentally robust and an updated approach towards a successful design was explained.

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The past two centuries have witnessed the rise of nationalist movements and widespread nationalism. As these movements gained strength in Europe, sport played a role in their development. Media representations of sport recount events in a way that reinforces cultural values and this research investigates media representations of Croatian nationalism in the weeks surrounding the country’s third place victory in the 1998 FIFA World Cup. Sociological theories alongside more contemporary theories of sport and nation construction are considered. Croatian newspapers were analyzed for elements of national identity construction. The study concludes that the 1998 World Cup played an important role in Croatia’s on-going construction of nationhood and invention of nationalist traditions. This research further demonstrates sport’s ability to evoke strong emotions that are difficult to witness in other areas of social life and the direct role of sport in garnering nationalism.

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Lightning Fastener Co. Ltd. was a zipper manufacturer located on Niagara Street in St. Catharines. It was founded by Gideon Sundback, the inventor of the modern fastener. Sundback was born in Sweden, but settled in the United States in 1905. It was here that he designed and patented a “separable fastener” in 1913. Although he lived in Hoboken, New Jersey, he decided to establish a manufacturing facility for his invention in Canada, choosing St. Catharines over other locations such as Fort Erie and Hamilton. At the height of its success, the company employed more than 500 people and produced more than 50 million zippers annually. Over time, the company had difficulty remaining competitive and was forced to close in 1981.