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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.
71

Taxonomy, ecology and palaeoecology of ostracods from Australian inland waters

De Deckker, P. (Patrick) January 1981 (has links) (PDF)
Typescript (photocopy)
72

Sediments and planktonic foraminifera of tropical North Atlantic cores

Ensminger, Henry Robert 04 August 1966 (has links)
Graduation date: 1967
73

Vertical flux, ecology and dissolution of radiolaria in tropical oceans : implications for the silica cycle /

Takahashi, Kozo. January 1982 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Science, 1982. / Supervised by Susumu Honjo. Vita. Includes bibliographies.
74

Vertical flux, ecology and dissolution of radiolaria in tropical oceans : implications for the silica cycle /

Takahashi, Kozo. January 1981 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1981. / Vita. Includes bibliographies.
75

The taphonomy of vertebrate archaeofaunas : bone density and differential survivorship of fossil classes /

Lyman, R. Lee. January 1982 (has links)
Thesis (Ph. D.)--University of Washington, 1982. / Vita. Bibliography: leaves 235-255.
76

A PREFEASIBILITY STUDY OF INTEGRATING WOODROLL GASIFICATION TECHNOLOGY INTO OVAKO STEEL AND HEAB REPLACING FOSSIL FUELS IN HOFORS

Moner Lasheras, Alodia Baldesca January 2012 (has links)
Biomass gasification is considered a key technology in reaching targets for renewable energy and CO2 emissions reduction. This thesis studies the feasibility of a new technology of biomass gasification called WoodRoll for the production of Syngas with the aim to replace fossil fuels in the furnaces of the steel company OVAKO in Hofors.  This research attempts to study the techno-economic viability of WoodRoll technology integration with the district heating company HEAB, creating a synergy between the companies and WoodRoll technology. Moreover, a theoretically study of the environmental impact, concerning greenhouse effect and pollutants it is also carried out.   In the future scenario HEAB, as an energy supplier will be the gasification plant owner supplying with Syngas 5% cheaper than the fuels that they use today to Ovako.  Three different scenarios have been studied varying the capacity of the gasification plant. The scenarios are 5MW, 10MW and 15MW capacity.   The study show that the system is technically viable being possible to create a synergy  between the three process improving efficiency and decreasing cost and CO2 emissions.   The results from the economic study show that biomass gasification using WoodRoll technology is a highly interesting investment option for HEAB. From Ovako side, the project is very interesting too since the company can have a combustible 5% cheaper than the fuels used today without doing any investment. In 5MW scenario, 40GWh per year are converted in Ovako from oil to Syngas. With an investment for HEAB of 9.8 mSEK, profits were a Net Present Value of 6.3mSEK with 7.8 years of payback period. In 10MW scenario 80GWh were replaced. In this scenario, required investment was 146 mSEK with a NPV of 32.5 mSEK . Payback in this case was 6.3 years. The most profitable scenario was the case of 15M. With an investment of 188 mSEK the profits of the project were 60mSEK with a payback period of 5.8 years. In the three cases, especially in 15MW case, sensitivity study of the system show that it is very robust to changes in biomass cost and Syngas price. This parameters have a big impact on the profits but a big margin until becomes unfeasible.   From Ovako side, savings for the fuel conversion were 1.2; 2.4 and 3.6mSEK for the 5, 10 and 15MW respectively. Reduction of CO2 emissions was 11, 20 and 30 thousands of CO2 tons for the three scenarios allowing  the company to sell CO2 allowances and having an extra profit of 3, 6 and 8mSEK per year in the 5, 10 and 15MW scenario respectively.
77

Carboniferous paleobotany and paleoclimatology of the central Appalachian Basin, West Virginia, U.S.A.

Blake, Bascombe Mitchel. January 2009 (has links)
Thesis (Ph. D.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains xi, 240 p. : ill. (some col.), maps (some col.). Vita. Includes abstract. Includes bibliographical references.
78

Beiträge zur Kenntnis der Farne und farnähnlichen Gewächse des Culms von Europa

Oberste-Brink, Karl, January 1914 (has links)
Inaug.-Diss.--Königlichen Westfälischen Wilhelms-Universität zu Münster i. W. / Lebenslauf. "Sonderabdruck aus dem Jahrbuch der Königl. Preuss. Geologischen Landesanstalt für 1914, Bd. 35, Teil 1, Heft 1.
79

Die Coniferen und Fagaceen des schlesischen Tertiärs ...

Reichenbach, Ernst, January 1912 (has links)
Inaug.-Diss.--Breslau. / Lebenslauf. Aus dem botanischen Garten der Universität Breslau. "Benutzte Literatur": p. 44-46.
80

El smilodon bonaërensis (Muñiz) estudio osteológico y osteométrico del gran tigre fósil de la Pampa comparado con otros félidos actuales y fosiles.

Mendez Alzola, Rodolfo. January 1941 (has links)
Tesis--Buenos Aires. / At head of title: Universidad de Buenos Aires. Facultad de Ciencias Exactas, Fisicas y Naturales. Reprinted from vol. 39 of Anales del Museo Argentino des Ciencias Naturales. "Bibliografía": p. 120-123.

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