• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1471
  • 278
  • 61
  • 39
  • 35
  • 25
  • 23
  • 23
  • 23
  • 23
  • 23
  • 22
  • 19
  • 8
  • 8
  • Tagged with
  • 2407
  • 808
  • 738
  • 574
  • 470
  • 441
  • 359
  • 354
  • 343
  • 276
  • 231
  • 227
  • 210
  • 158
  • 150
  • 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.
211

Technical Fesibility of Flakeboard Production from Recycled CCA-Treated Wood

Li, Wei 09 July 2002 (has links)
Chromated copper arsenate (CCA) treated wood is an economical, durable and aesthetically pleasing residential material used for many exterior application such as decks, fences, playground equipment, utility poles, and others. It has been most widely used in North America since the 1970s. A large volume of CCA-treated wood is currently coming out of service. Traditional landfilling or incineration is environmentally unacceptable. Recycling CCA-treated wood into composite products is one alternative to ease the disposal problem. It also has the potential to relieve harvesting pressure from the nation's forestlands. After recycling, the remaining CCA content in the wood can still have preserving capability against decay. In this study, the effects of different ratios of recycled CCA-treated wood and untreated virgin wood on flakeboard properties were compared. The mechanical, physical, decay resistance, elemental concentrations, and leaching characteristics of flakeboards manufactured from five different ratios of recycled CCA-treated wood and untreated virgin southern pine wood were investigated. The ratios were 100:0, 75:25, 50:50, 25:75, and 0:100. The CCA retention levels of out-of-service CCA-treated posts (experimental raw material) as well as the flakeboard fabricated from the different ratios of recycled CCA-treated wood and untreated virgin wood were also tested. The median ratio with 50% of CCA-treated wood and un-treated wood was found to be the optimum combination. In this case, residual CCA level was sufficient enough to prevent substantial weight losses for the decay tests but low enough so that panel mechanical and physical properties were not substantially adversely affected.
212

Diet Similarity of Pen-Raised Versus Native, Louisiana White-Tailed Deer in Southeastern Louisiana

Davis, Kristopher Scott 20 November 2003 (has links)
Previous studies have shown that pen-raised deer may be already predisposed to malnutrition at a higher rate then their native counterparts because they are normally raised on a pelleted ration and may not forage efficiently once released into wild habitats. Therefore, twenty pen-raised white-tailed deer that were offspring of deer obtained from Missouri (Odocoileus virginianus) were released onto a marsh pump-off habitat in southeast Louisiana (Da Bunch) to compare their diets to the diets of the native, wild, white-tail deer population already established in the area over four consecutive seasons to test this hypothesis. The microhistological analysis technique was used to estimate the botanical compositions of fecal pellets collected from both populations of deer located in the same range, over four consecutive seasons (Spring, Summer, Fall, and Winter) to account for seasonal variability. Native, wild and pen-raised deer diets averaged 78.2% similar during the year of the study, and were significantly associated to one another during each of the four seasons (P < 0.00001), indicating that all deer foraged on similar plant species in similar proportions. Differences were found in species frequencies per fecal sample, but for only five of the fifty-one species utilized significant differences were found (P < 0.001) between populations. Those species were Diodia virginiana in the spring, Aeschynomene americana, Ambrosia spp. during fall, and Berchemia scandens and Celtis laevigata in the winter. Both deer populations were predominantly grazers, with forbs constituting for a yearly average of 41.20% the deer diets. This study agrees with previous studies that concluded that translocated deer released into a new environment will adapt to the area and forage just as efficiently as the pre-existing deer population in the area assuming carrying capacity is not compromised.
213

Developing a wildlife tracking extension for ArcGIS

Chen, Cai. Dong, Pinliang, January 2009 (has links)
Thesis (M.S.)--University of North Texas, May, 2009. / Title from title page display. Includes bibliographical references.
214

Wildlife habitat conservation policy in Canada the role of international agreements for policy development /

Statham, Kimberley A. January 1999 (has links)
Thesis (M.E.S.)--York University, 1999. Graduate Programme in Environmental Studies. / Typescript. Includes bibliographical references (leaves 78-84). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ44669.
215

Modeling optimal management strategies for Piping plover in the Great Plains

Larson, Michael A. January 2001 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
216

Prey and range use of lions on Tswalu Kalahari Reserve

Roxburgh, David James. January 2009 (has links)
Thesis (M. Sc.(Wildlife Management)(Animal and Wildlife Sciences)--University of Pretoria, 2009. / Summaries in English.
217

Aspects of Key Largo woodrat ecology

McCleery, Robert Alan, January 1900 (has links)
Thesis (M.S.)--Texas A & M University, 2003. / "Major Subject: Wildlife and Fisheries Sciences." Title from author supplied metadata (automated record created on Apr. 30, 2004.). Vita. Abstract. Includes bibliographical references.
218

Survival and mammalian predation of Rio Grande Turkeys on the Edwards Plateau, Texas.

Willsey, Beau Judson, January 1900 (has links)
Thesis (M.S.)--Texas A & M University, 2003. / "Major Subject: Wildlife and Fisheries Sciences." Title from author supplied metadata (automated record created on Apr. 30, 2004.). Vita. Abstract. Includes bibliographical references.
219

The effect of supplemental food on gray squirrel movements and reproduction

Heller, David Mark. January 1978 (has links)
Thesis (M.S.)--Ohio State University. / Bibliography: leaves 82-87. Available online via OhioLINK's ETD Center
220

Modeling optimal management strategies for Piping plover in the Great Plains /

Larson, Michael A. January 2001 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.

Page generated in 0.4177 seconds