Arsenic speciation by ion-exchange chromatography with on- line determination by hydride generation: electronic modification of the D.C. plasma by photon counting

A method using L-cysteine for the determination of arsenous acid (As(III)), arsenic acid (As(V)), monomethylarsonic acid (MMAA), and dimethylarsinic acid (DMAA) by hydride generation was demonstrated. The instrument used was a d.c. plasma atomic emission spectrometer (OCP-AES). Complete recovery was reported for As(III), As(V), and DMAA while 86% recovery was reported for MMAA. Detection limits were determined, as arsenic for the species listed previously, to be 1.2, 0.8, 1.1, and 1.0 ngemL-l, respectively. Precision values, at 50 ngemL-1 arsenic concentration, were f.80/0, 2.50/0, 2.6% and 2.6% relative standard deviation, respectively. The L-cysteine reagent was compared directly with the conventional hydride generation technique which uses a potassium iodide-hydrochloric acid medium. Recoveries using L-cysteine when compared with the conventional method provided the following results: similar recoveries were obtained for As(III), slightly better recoveries were obtained for As(V) and MMAA, and significantly better recoveries for DMAA. In addition, tall and sharp peak shapes were observed for all four species when using L-cysteine. The arsenic speciation method involved separation by ion exchange .. high perfonnance liquid chromatography (HPLC) with on-line hydride generation using the L.. cysteine reagent and measurement byOCP-AES. Total analysis time per sample was 12 min while the time between the start of subsequent runs was approximately 20 min. A binary . gradient elution program, which incorporated the following two eluents: 0.01 and 0.5 mM tri.. sodium citrate both containing 5% methanol (v/v) and both at a pH of approximately 9, was used during the separation by HPLC. Recoveries of the four species which were measured as peak area, and were normalized against As(III), were 880/0, 290/0, and 40% for DMAA, MMAA and As(V), respectively. Resolution factors between adjacent analyte peaks of As(III) and DMAA was 1.1; DMAA and MMAA was 1.3; and MMAA and As(V) was 8.6. During the arsenic speciation study, signals from the d.c. plasma optical system were measured using a new photon-signal integrating device. The_new photon integrator developed and built in this laboratory was based on a previously published design which was further modified to reflect current available hardware. This photon integrator was interfaced to a personal computer through an AID convertor. The .photon integrator has adjustable threshold settings and an adjustable post-gain device.

Electrical Development Company of Ontario certificate of stock ownership, ca. 1910.

The Electrical Development Company of Ontario was created in 1903. It was one of three private power companies that had water power leases with the Niagara Parks Commission, but was the only one that was financed with Canadian capital. The company built the Toronto Power Generating Station at Niagara Falls beginning in 1906, and the power house was completed in 1913. During the construction, there was much debate about whether the utility should remain privately operated or become a public utility. In 1920, the company became part of the public utility.

Letter addressed by Benjamin Bates (bearer of the memorial) to a Member of the Legislature, ca. 1812.

Benjamin Bates was a member of the Religious Society of Friends, and served as Clerk of the Society at the time that the Memorial and Petition was written.

Letter addressed by Benjamin Bates (bearer of the memorial) to a Member of the Legislature, ca. 1812.

Benjamin Bates was a member of the Religious Society of Friends, and served as Clerk of the Society at the time that the Memorial and Petition was written.

Opinion Regarding the Estate of S.D. Woodruff

An opinion regarding the estate of S.D. Woodruff. This is in regard to the liability of the estate to pay succession duties in Ontario upon certain American bonds and securities in the City of New York. This is a 6 page printed document prepared by Dewart, Young and Maw - February 7, 1905.

Estate of S.D. Woodruff in Account with H.H. Collier

The estate of S.D. Woodruff in account with H.H. Collier. This contains 1 1/2 printed pages listing expenses to be paid to Johnson Clench for copy of depositions, 1906-1907.

Almanac of S.D. Woodruff of St. Catharines

Almanac of S.D. Woodruff of St. Catharines (soft cover) containing records of items sold to various people, 1858-1866.

Canadian Bank of Commerce (vinyl cover), St. Catharines bank book of Welland D. Woodruff Esq.

Canadian Bank of Commerce (vinyl cover), St. Catharines bank book of Welland D. Woodruff Esq., 1915-1917.

List of inventory of goods in the dwelling of S.D. Woodruff of St. Catharines

List of inventory of goods (6 pages, handwritten) in the dwelling of S.D. Woodruff of St. Catharines. This list was examined by William Walker on Oct. 30, 1862 and compiled on Oct. 27, 1862.

List of inventory of goods in the dwelling of S. D. Woodruff, Ontario Street, St. Catharines

List of inventory (5 pages, handwritten) of goods in the dwelling of S. D. Woodruff, Ontario Street, St. Catharines, n.d.

List of abstracts (2 pages, handwritten) stating the cost of S.D. Woodruff dwelling and barns

List of abstracts (2 pages, handwritten) stating the cost of S.D. Woodruff dwelling and barns, January, 1878.

Memorandum of S.D. Woodruff’s property on Ontario Street

Memorandum (1 page, handwritten) of S.D. Woodruff’s property on Ontario Street, Jul. 25, 1901.

Letter to the Estate of W.D. Woodruff from S. Mitchell, secretary of the Lincoln Paper Mills Company

Letter to the Estate of W.D. Woodruff from S. Mitchell, secretary of the Lincoln Paper Mills Company (1 page, printed). This is a notice of the 43rd annual meeting of the shareholders of the Lincoln Paper Mills Company, Limited. This is accompanied by an envelope, Feb. 7, 1921.

Bishop Fuller’s Charge, n.d.

Thomas Brock Fuller was born in 1810 in Kingston, Ont. and died in 1884 in Hamilton, Ont. At the age of seven he was adopted by his aunt Margaret and her husband Rev. William Leeming, a Church of England missionary in Niagara. Fuller would go on to become a minister himself, serving in Montreal, Lachine, Chatham, Thorold and Toronto. In 1875 he became the first bishop of the new diocese of Niagara. Thomas Brock Fuller was married to Cynthia Street, daughter of well-known merchant Samuel Street. Together they raised a family of six sons and three daughters. The poem may have been written by Thomas Brock Fuller himself.

Grade 9 students' perceptions of the impact of a Drop Everything and Read (D.E.A.R.) program /

Educators continually look for strategies to enhance and improve the reading practices of their students. This is an especially challenging task for secondary level teachers as high school students often lack intrinsic motivation to read for pleasure (Bucher & Manning, 2004; Horton, 2005; Wooicott, Research Pty. Ltd. 2001). The purpose of this study was to detennine the effects of the Drop Everything and Read (D.E.A.R.) program on writing, on reading, and on grades, from the perspective of eight Grade 9 students. Of particular interest were the students' perceptions of the effect that participation in the program had on their grades, their writing, their motivation to reading, and their concept of themselves as readers. The eight participants were tracked over the course of a semester. Using qualitative research techniques, data were collected from four sources: two student surveys, researcher's daily field observations, students' weekly reading logs, and three open-ended one-on-one interviews. In order to gain an understanding of the impact of the D.E.A.R program, the data were corroborated, and analyzed with NVivo: N7 (2006). From the data analysis, five themes emerged as a function of the Grade 9 students' experiences in the D.E.A.R. program: Reading Preferences, Time Spent Reading, Making Associations with Reading for Pleasure, Perceptions of Self-as-Reader, and Evaluations of the D.E.A.R Program. In the interest of supporting students' positive reading habits and for the future implementation, these five themes are presented as a series of findings together with recommendations for practice.