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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.
41

Nitrogen exchange between plants through common mycorrhizal networks /

He, Xinhua. January 2002 (has links) (PDF)
Thesis (Ph.D.) - University of Queensland, 2004. / Includes bibliography.
42

Nitrogen fixation by cell-free extracts of Klebsiella pneumoniae

Mahl, Mearl C., January 1966 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1966. / Typescript. Vita. Nitrogen fixation by members of the tribe Klebsielleae [by] M.C. Mahl ... [et al.] : leaves 7-12. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
43

Formation of nitrogenase in Clostridium pasteurianum

Detroy, Robert William, January 1967 (has links)
Thesis (Ph. D.)--University of Wisconsin, 1967. / "Nitrogen fixation by growing cells and cell-free extracts of the of the bacillaceae [by] D.F. Witz, R.W. Detroy and P.W. Wilson, [reprinted from] Archiv für mikrobiologie 55, 369-381, 1967" inserted between leaves [9]-[23]. Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
44

Nitrogen isotope variation in the environment : implications for interpretation /

Tozer, Wade. January 2006 (has links)
Thesis (Ph.D. Biological Sciences)--University of Waikato, 2006. / Includes bibliographical references (leaves 181-196) Also available via the World Wide Web.
45

Phylogenetic diversity of nifH genes in Marion Island soil

Rapley, Joanne January 2006 (has links)
Magister Scientiae - MSc / The microbial life of sub-Antarctic islands plays a key role in the islands ecosystem, with microbial activities providing the majority of nutrients available for primary production. Knowledge of microbial diversity is still in its infancy and this is particularly true regarding the diversity of micro-organisms in the Antarctic and sub-Antarctic regions. One particularly important functional group of micro-organisms is the diazotrophs, or nitrogen-fixing bacteria and archaea. This group have not been well studied in the sub-Antarctic region, but play an important role in the nutrient cycling of the island. This thesis explored the diversity of nitrogen-fixing organisms in the soil of different ecological habitats on the sub-Antarctic Marion Island. / South Africa
46

Stanovení optimální ceny v akčním a běžném prodeji ve spolupráci s Pfanner, spol. s r.o. / Fixing the optimal common and action price in the cooperation with the Pfanner, spol. s r.o.

Bříštělová, Radka January 2009 (has links)
The price strategy and the right propose of price level play fundamental part in every company with successfull leadership. Especially nowadays, when the sensitivity of customers is growing and not only in the sphere of price but also promotion. It seems, in the case of product category of juices Pfanner, which are processed in this graduation theses, is this fact valid especially. What the price and sales development do the main players note in this market is analysed pursuant to secondary data of research agency MEMRB Retail Services. The reception of brand image and the customers behavior comes from study TNS AISA. The graduation these is trying to find the answer especially on these questions: Can the company Pfanner keep the high quality brand image and increase sales at the same time? What level of price can, together with certain promotion activities, ensure higher turnover but at the same time not damage the long time builded brand image? What is the optimal level of common and action price of Pfanner products?
47

Low root-zone temperatures and soybean (Glycine max (L.) Merr.) N2- fixing symbiosis development

Lynch, Derek H. (Derek Henry) January 1992 (has links)
No description available.
48

Ridge regression signal processing applied to multisensor position fixing

Kuhl, Mark R. January 1990 (has links)
No description available.
49

The effects of P fertilizer addition on P transformations on high-P fixing and grassland soils

Pierzynski, Joy January 1900 (has links)
Doctor of Philosophy / Department of Agronomy / Ganga M. Hettiarachchi / Although phosphorus (P) is an essential nutrient for the growth of plants, it is one of the most limiting nutrients in terms of availability as a high proportion of applied P rapidly transforms into insoluble forms with low solubility in soils. To further understand the fate of P applied to soils, two separate but related studies using three high P-fixing soil types each were used for which the objectives were to investigate the mobility, availability, and reaction products from two granular and one liquid P fertilizer alone or plus a fertilizer enhancement product. Energy dispersive spectroscopy showed a substantial amount of P remained in the granule following a 5-week incubation. At the end of the 35-day incubation period there was evidence that the fluid fertilizer was superior over the granular sources in terms of enhanced diffusion and extractability of P for three calcareous soils with varying levels of CaCO₃. Phosphorus x-ray absorption near-edge structure (XANES) spectroscopy results in conjunction with resin-extractable P indicated a strong negative correlation between Ca-P solids formed and P extractability, suggesting that degree of Ca-P formation limits P solubility. For the three acidic P-fixing soils the results were complex. In two out of three acid soils, liquid P treatments diffused farther from the application point than the granular treatments. Phosphorus XANES results suggested that Fe-P or Al-P interactions control the overall P solubility. Integration of pH, resin extractable-P and XANES results suggested the P retention mechanism was either dominated by adsorption or precipitation depending on soil pH. More acidic soil conditions favored precipitation. The objectives of the third study were to observe how long-term (14 years) addition of P with or without N influences the inorganic and organic P pools in a native grassland soil using sequential fractionation, XANES, and ³¹P-nuclear magnetic resonance (NMR) spectroscopy. The overall results suggested that P and N fertilization and associated changes in plant productivity induced significant changes in soil P pools such as Ca-P, phytic acid, monoesters, and residual forms of P. The addition of P alone induced formation of inorganic P forms while the addition of P and N induced transformation of residual P forms into more labile and/or organic P forms.
50

Development of a genetic system in Rhizobium meliloti.

Meade, Harry Melvin January 1977 (has links)
Thesis. 1977. Ph.D.--Massachusetts Institute of Technology. Dept. of Biology. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Includes bibliographical references. / Ph.D.

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