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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Evaluating the Effect of Biodiesel on the Efficacy of the Wood Preservative Copper Naphthenate

McKillop, Natasha 06 March 2014 (has links)
The efficacy of biodiesel as a co-solvent for copper naphthenate wood preservative treating solutions was evaluated using two fungal decay methodologies (AWPA E10-09, British Standard Method EN113). Four fungal species (Gloeophyllum trabeum, Trametes versicolor, Poria xantha, Postia placenta) and three wood species (Douglas fir, Southern yellow pine, Western red cedar) with six replicates were utilized in both studies. Two levels of biodiesel: diesel (30:70 and 50:50) were compared to diesel-only solvent systems for copper naphthenate treating systems and treated to AWPA recommended retentions. No differences in decay efficacy between the biodiesel blends and diesel-only treatment in either the AWPA or the EN113 decay studies were detected for either standard method. Copper distribution was evaluated using SEM-EDX and no differences were noted with either solvent system. It was determined that the presence of biodiesel did not have a negative impact upon the efficacy of copper naphthenate as a wood preservative.
2

Deterioration of burlap in soil as influenced by treatment with copper fungicides; and the effects of toxic copper levels on four plant genera

Kuhns, Larry Judson January 1974 (has links)
No description available.
3

Mechanical and physical properties of preservative-treated strandboard

Kirkpatrick, John Warren, January 2005 (has links)
Thesis (M.S.) -- Mississippi State University. Department of Forest Products. / Title from title screen. Includes bibliographical references.
4

Synthesis of β-cyclodextrin and chitosan-based copolymers for the removal of naphthenic acids

2013 March 1900 (has links)
Naphthenic acids (NAs) are a group of carboxylic acids that are found in hydrocarbon deposits such as the oil sands bitumen. These compounds are a well-known corrosive agent and a toxic component in the oil sands process water (OSPW). Due to Alberta’s zero discharge policy, OSPW cannot be released and must be stored until toxic components like NAs are remediated. One technique that has shown potential is to physically adsorb NAs onto a copolymer generated from economical biomaterials. Therefore, the project can be divided into three sections: 1) Synthesis of β-cyclodextrin (β-CD) copolymer for the sorption of p-nitrophenol (PNP); 2) Synthesis of chitosan-based copolymers (Chi-Glu) for the sorption of PNP; 3) Sorption of carboxylates and NAs using Chi-Glu copolymers. PNP sorption was used as a probe to understand the physicochemical properties of the copolymers. In the first section, β-CD was reacted with sebacoyl chloride (SCl) and terephthaloyl chloride (TCl) at various mole ratios. Characterization was done using Fourier Transform Infrared Spectroscopy (FT-IR), thermogravimetric analysis (TGA), 1H NMR spectroscopy (1H NMR), elemental analysis (CHN), and nitrogen porosimetry. Copolymers synthesized at mole ratios of β-CD to SCl from 1:1 to 1:3 were hydrolyzed at acidic and basic conditions. Therefore, sorption studies were not done at these ratios. The same occurred for 1:1 to 1:3 TCl copolymers. Sorption studies with PNP at pH 4.6 demonstrated enhanced sorption capacity when comparing with a standard: granular activated carbon (GAC). The sorption capacity, Qm (mmol/g), ordered from largest to smallest is 1:9 SCl>1:9 TCl>1:6 SCl> GAC> 1:6 TCl. Chi-Glu copolymers were synthesized by cross-linking glutaraldehyde with pristine chitosan. A systematic study on the effects reaction conditions have on the sorption capacity of the materials was done. Three conditions were changed: pH, temperature, and mole ratios. Chi-Glu copolymers were synthesized at various chitosan to glutaraldehyde mole ratios (1:400, 1:700, 1:1000). Sufficient time was allowed for the aging process. Characterization was done using TGA, FT-IR, CHN, and nitrogen porosimetry. Sorption study with PNP were done at pH = 7.0 and 9.0. At pH = 7.0 sorption capacity appears to correlate to the quantity of homo-polymerized glutaraldehyde: 1:700>1:1000>1:400. While at pH = 9.0, the sorption capacity is inversely proportional to the degree of crosslinking: 1:400>1:700>1:1000. By increasing the pH at the shrinkage phase, PNP was weakly bound onto the Chi-Glu copolymer. Varying temperature before gelation caused a decrease in the sorption capacity with PNP. Sorption studies involving carboxylates and NAs were done at pH = 9.0 at ambient temperature using Chi-Glu copolymers (1:400, 1:700, and 1:1000) and chitosan. Three carboxylates were chosen to reflect the diverse components in NAs. Varying degrees of cyclization (Z = 0, -2, -4) and lipophilic surface area were the main criteria for carboxylates. The sorption capacity depended mainly on the lipophilic surface area (LSA) with sorption capacity highest for 2-hexyldecanoic acid (S1) which has the largest LSA and lowest for, trans-4-pentylcyclohexanecarboxylic acid (S2) and dicyclohexylacetic acid (S3). Unfortunately, cross-linking with glutaraldehyde does not enhance sorption as pristine chitosan retained a higher sorption capacity compared to Chi-Glu copolymers. Acros and Fluka NAs were chosen for sorption and no significant sorption was recorded for any copolymers. Problems involving the micellization process can explain the lack of sorption.
5

Mechanical And Physical Properties Of Preservative-Treated Strandboard

Kirkpatrick, John Warren 10 December 2005 (has links)
The purpose of this research was to quantify properties of strandboard panels manufactured with various preservatives at loading levels effective against native termites. Panels were manufactured using nine different formulations. The method of preservative addition was also examined for some preservative formulations, increasing the total number of preservative treatments to twelve. Panels were manufactured with one target retention for each preservative treatment. An effective preservative loading relative to termites was established by previous studies or referencing current standards. Mechanical testing performed included static bending and internal bond. Physical testing included water absorption, thickness swell, and linear expansion. Few treatments met the Canadian standards for strandboard, but several preservatives performed well. Copper naphthenate, bifenthrin, and copper betaine each deserve further investigation to optimize manufacturing variables to meet required mechanical and physical properties.

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