Polytypism and Silicon carbide : a solid state nuclear magnetic resonance study

A survey of predominantly industrial silicon carbide has been carried out using Magic Angle Spinning nuclear magnetic resonance (MAS nmr); a solid state technique. Three silicon carbide polytypes were studied; 3C, 6H, and 15R. The 13C and 29 Si MAS nmr spectra of the bulk SiC sample was identified on the basis of silicon (carbon) site type in the d iff ere n t pol Y t Y pes • Out to 5.00 A fro mac en t r a lsi 1 i con (0 r carbon) atom four types of sites were characterized using symmetry based calculations. This method of polytype analysis was also considered, in the prelminary stages, for applications with other polytypic material; CdBr 2 , CdI 2 , and PbI 2 " In an attempt to understand the minor components of silicon carbide, such as its surface, some samples were hydrofluoric acid washed and heated to extreme temperatures. Basically, an HF removable species which absorbs at -110 ppm (Si0 2 ) in the 29 Si MAS nmr spectrum is found in silicon carbide after heating. Other unidentified peaks observed at short recycle delays in some 29 Si MAS nmr spectra are considered to be impurities that may be within the lattice. These components comprise less than 5% of the observable silicon. A Tl study was carried out for 29 Si nuclei in a 3C ii polytype sample, using the Driven Equilibrium Single-Pulse Observation of T1 (DESPOT) technique. It appears as though there are a number of nuclei that have the same chemical shift but different T1 relaxation times. The T1 values range from 30 seconds to 11 minutes. Caution has to be kept when interpreting these results because this is the first time that DESPOT has been used for solid samples and it is not likely in full working order. MAS nmr indicates that the 13C and 29 Si ~sotropic chemical shifts of silicon carbide appear to have a reciprocal type of relationship_ Single crystal nmr analysis of a 6H sample is accordance with this finding when only the resultant isotropic shift is considered. However, single crystal nmr also shows that the actual response of the silicon and carbon nuclear environment to the applied magnetic field at various angles is not at all reciprocal. Such results show that much more single crystal nmr work is required to determine the actual behavior of the local magnetic environment of the SiC nuclei.

Magnetic and transport properties of (Ba1-xKx)Fe2As2

Single crystals of (Bal - xKx)Fe2As2 were prepared using the Sn flux method. Two heating methods were used to prepare the single crystals: the slow heating and rapid heating methods. It was found that the single crystals grown using the slow heating method were not superconducting due to a significant loss of potassium. When the rapid heating method was used, the single crystals were observed to be superconducting with the desired potassium concentration. The energy dispersive X-ray spectroscopy analysis indicated the presence of multiple phases in the single crystals. Using single crystal X-ray diffraction, the crystal structure of the single crystals was found to be 14/mmm tetragonal at room temperature. The magnetic measurements on the single crystals indicated the presence of multiple phases and magnetic impurities.

Lighting recommendations for the Ryan Electric Scintillator and Fireworks Program for the official dedication Niagara Falls illumination, 1925

Walter D’Arcy Ryan was born in 1870 in Kentville, Nova Scotia. He became the chief of the department of illumination at the General Electric Company of Schenectady, New York. He was a founder in the field of electrical illumination. He built the electric steam scintillator which had numerous nozzles and valves. The operator would release steam through the valves. The nozzles all had names which included: Niagara, fan, snake, plume, column, pinwheel and sunburst. The steam scintillator was combined with projectors, prismatic reflectors, flashers and filters to produce the desired effects. In 1920 a group of businessmen from Niagara Falls, New York formed a group who called themselves the “generators’. They lobbied the American and Canadian governments to improve the illumination of the Falls. They were able to raise $58, 000 for the purchase and installation of 24 arc lights to illuminate the Falls. On February 24th, 1925 the Niagara Falls Illumination Board was formed. Initially, the board had a budget of $28,000 for management, operation and maintenance of the lights. The power was supplied free by the Ontario Power Company. They had 24 lights installed in a row on the Ontario Power Company surge tank which was next to the Refectory in Victoria Park on the Canadian side. The official opening ceremony took place on June 8th, 1925 and included a light parade in Niagara Falls, New York and an international ceremony held in the middle of the Upper Steel Arch Bridge. Walter D’Arcy Ryan was the illuminating engineer and A.D. Dickerson who was his New York field assistant directed the scintillator. with information from American Technological Sublime by David E. Nye and the Niagara Falls info website Location: Brock University Archives Source Information: Subject Headings: Added Entries: 100 Ryan, W. D’A. |q (Walter D’Arcy), |d 1870-1934 610 General Electric Company 650 Lighting, Architectural and decorative 650 Lighting |z New York (State) |z Niagara Falls 700 Dickerson, A.F. 700 Schaffer, J.W. Related material held at other repositories: The Niagara Falls Museum in Niagara Falls, Ontario has a program (pamphlet) dedicating new lighting in 1958 and it has postcards depicting the illumination of the Falls. Some of Ryan’s accomplishments can be seen at The Virtual Museum of the City of San Francisco. Described by: Anne Adams Date: Sept 26,Upper Steel Arch Bridge. Walter D’Arcy Ryan was the illuminating engineer and A.D. Dickerson who was his New York field assistant directed the scintillator. with information from American Technological Sublime by David E. Nye and the Niagara Falls info website

Hydro Electric Commission of Niagara Falls Ontario Scrapbook, 1936-1939, 1943-1951

Sir Adam Beck ( a London, Ontario manufacturer, Mayor and Conservative member of the provincial legislature) was a champion of municipal and provincial power ownership. Beck become the “Power Minister” and chairman of the Hydro-Electric Power Commission of Ontario which was the world’s first publicly owned utility. In 1925 the first unit of the Hydro Electric Power Commission’s Queenston Chippawa hydro-electric development on the Niagara River went into service. The station was renamed in 1950 as “Sir Adam Beck #1”. This marked the 25th anniversary of Beck’s death. This is one of 2 generating stations in Niagara Falls. There is also Adam Beck Plant #2. The Niagara generating stations supply one quarter of all power used in New York State and Ontario.Ontario Hydro has two water tunnels which traverse the entire City of Niagara Falls from the Village of Chippawa in the South to the Sir Adam Beck Hydro Electric Generating Stations in the North. Also they are in the process of building the third tunnel. In addition, Ontario Hydro has a 13.6 km open canal which traverses the entire City of Niagara Falls. Source: http://www.hydroone.com/OurCompany/Pages/OurHistory.aspx

Letter - Frederic Nicholls (Canadian General Electric) to W.B. Rankine, 17 December 1897

A letter from 2nd Vice President and General Manager of Canadian General Electric Company, Frederic Nicholls to W. B. Rankine regarding a bid for contract. The letter mentions that the bid for two alternating generators for the Canadian side of Niagara Falls was won by Westinghouse Eletric and Manufacturing Co. Nicholls also mentions that there will be other opportunites to win contracts as more machines are required. Nicholls also implies that Westinghouse may have bid under cost in an effort to secure the first of many contracts with the Canadian Niagara Power Company.

Fourth Annual Report of The Electric Development Company of Ontario Limited For the Year Ending 31st December, 1906

Fourth Annual Report of The Electrical Development Company of Ontario Limited for for the year 1906. The report discusses the main line between Niagara Falls and Toronto and the line between the Township of Pelham and the city of Brantford. The report also details the purchase of stocks and bonds in several different companies.

The Hydro-Electric Power Commission of Ontario: address. (1923)

The Public Ownership League of America Conference, September 10th to 13th, 1923, at Toronto, Ontario.

Receipt from Geo. Lloyd of St. Catharines for work done regarding heating and pipes

Receipt from Geo. Lloyd of St. Catharines for work done regarding heating and pipes, Jan. 1, 1877.