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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.

A comparative study of several methods of assessing item bias

Ironson, Gail Hilarie, January 1977 (has links)
Thesis--Wisconsin. / Vita. Includes bibliographical references (leaves 82-85).

Effect of immediate self-check upon response to objective tests

McIntosh, Wayne Wesley January 2011 (has links)
Typescript, etc. / Digitized by Kansas State University Libraries

Computer aided ultrasonic flaw detection and characterization /

Tsang, Wai-ming, Peter. January 1987 (has links)
Thesis (Ph. D.)--University of Hong Kong, 1987.

Experimental designs for estimating the correlation between two destructively tested variables

Anorim, Sebastiao de. January 1982 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaf 89).

Data structures and reduction techniques for fire tests : fire engineering research thesis : a research thesis submitted in partial fulfilment of the requirements for the degree of Master of Engineering in Fire Engineering at the University of Canterbury /

Tobeck, Daniel O. January 1900 (has links)
Thesis (M.E.F.E.)--University of Canterbury, 2007. / Typescript (photocopy). "November 2007." Includes bibliographical references (p. 243-245). Also available via the World Wide Web.

Quantitative ultrasonic evaluation of concrete

Whitcomb, Richard W. 12 1900 (has links)
No description available.

The ultimate strength of load-bearing brick and block masonry walls /

Ojinaga, José I. January 1976 (has links)
No description available.

Investigation of the mechanism of failure of neat cement and mortar specimens

Urruela, Juan Francisco January 1954 (has links)
The problem of the investigation of the mechanism of failure in compression of neat cement and mortar specimens is considered in this thesis. The study was made on two hundred specimens of cement paste and mortar, of which approximately one half were tension briquets and the other half compression cylinders. The underlying theory which led to this study was that failure in compression in specimens with aggregate (mortar and concrete) is due to the wedging action of the particles of aggregate within the matrix of cement paste. Steam-curing was used to avoid delay in the hardening of cement. It was found that the cement used was of the type which continues hardening after being steam-cured. The importance of having the specimens at a constant temperature throughout their mass and at room temperature when the tests were performed was realized. An investigation of the effect of end conditions on test cylinders in compression was conducted. It is considered that the confined rubber end conditions used were an improvement on testing with lubricated ends only. Observations were made on the effect of the bursting action of water in compression tests of moist specimens. A study of the effect of stress concentration around voids was made on tension specimens. Compression specimens made of neat cement, mortar and cement with inclusions in the form of balls were studied. Inclusions were placed in cement cylinders to imitate the action of the aggregate in mortar and concrete specimens. Tests on compression specimens with inclusions were useful in the interpretation of results of tests on neat cement and mortar cylinders and in the study of the stress-strain curves. Transverse bending tests of cylinders were made with the purpose of investigating the presence of transverse cracks formed in the cylinders as a consequence of the application of compressive loads. They did not provide a good method of investigation but were very useful in that they were an aid to realizing the effect of the horizontal cracks in the stress-strain curves. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate

Behaviour of the major resin- and fatty acids of slash pine (Pinus elliottii) during organosolv pulping

Quinde Abad, Augusto January 1990 (has links)
A high extractive-content temperate conifer wood (Pinus elliottii) was examined as a pulpwood source by organosolv pulping. Particularly, the behavior of the resin- and fatty acids during the lignin solvolysis process was studied in detail. For this purpose the resin-and fatty acids were characterized in the wood, and after pulping trials in order to reveal their fate during pulping, using catalyzed 80% aqueous alcohol (methanol) as solvent. Wood extractives were removed by both methanolic cold maceration and Soxhlet extraction techniques. The resin-and fatty acid fractions thus collected were saponified and/or methylated and characterized by gas liquid chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). No significant differences were found in regard to extraction efficiencies between the two types of cold extractions. Furthermore, there was no significant difference between these two types of cold extractions in comparison with the procedure described by TAPPI standard T 204 os-76. Pulping experiments were performed at 205°C for periods of 5, 20, 40, and 60 min. Lignins, which precipitated on cooling of the black liquor (Lignin fraction I), were set aside for further extractions and chemical analyses. The molecular weight distribution of these lignins was determined by size exclusion chromatography on an HPLC and their quantity was determined either gravimetrically or volumetrically. Precipitated Lignin Fraction I, suspected of containing some adsorbed extractives and some fiber fragments, was transferred to a tared crucible. The lignin and extractives were sequentially dissolved by using tetrahydrofuran (THF), acetone and methanol. This solution was evaporated, the residue redissolved in methanol-water (80:20) and the solution liquid-liquid extracted with diethyl ether in a separatory funnel followed by methylation prior to GC and GC-MS analysis. Quantification of the resin- and fatty acids in the wood and those recovered after organosolv pulping was performed using an internal standard (methyl heptadecanoate) added prior to the extraction steps. The extractives dissolved in the black liquor were isolated by a ternary liquid-liquid extraction scheme using diethyl ether, methylated with fresh diazomethane, and the resin- and fatty acids methyl esters characterized by GC and GC-MS. The extractives present in the pulp were isolated (removed) by a Soxhlet extraction procedure with methanol and" the resin- and fatty acids fractions characterized as above. Resin- and fatty acids surviving the high-temperature pulping process, were found mainly in the black liquor. After the 60 min cook, the black liquor contained 78.1% and 71.6% of resin- and fatty acids, respectively, while the pulp retained 11.7% and 8.2%, respectively of the extractives originally present in wood. "Lignin fraction I" adsorbed 10.2% and 20.2% of the resin- and fatty acids, respectively. Contrarily, if all of the lignin is precipitated (Lignin fraction II). prior to liquid/liquid extraction of the black liquor with diethyl ether, 98% and 60.4% of the resin- and fatty acids co-precipitate with the lignin and 2.0% and 39.6%, respectively, remain dissolved in the aqueous filtrate. Industrial organosolv lignin isolated after solvent pulping of pine was thus shown to contain most (98%) of the resin acids and 39.6% of the fatty acids normally found in pines. Although not tested, it is supposed that lignins isolated by precipitation from the black liquor after organosolv pulping of other species cannot be considered as "pristine lignins" as described hitherto in the technical literature, since such lignins are heavily contaminated by the extractives of the wood species. In light of these findings all data on chemical and physical characterization of organosolv lignins and their reactivity will have to be reexamined and reassessed to remove the effect of the extractives as contaminants. / Forestry, Faculty of / Graduate

Development of an improved technique for variable velocity tensile impact testing of ultra-high strength aerospace materials

Makhijani, Purshotam Gobindram, 1938- January 1966 (has links)
No description available.

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