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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.
81

Model char studies on nitrogen release during coal char combustion

Spracklin, Christopher John January 1999 (has links)
No description available.
82

EFFECTS OF PRE-PLANT APPLICATION OF NITROGEN FERTILIZER ON SYMBIOTIC NITROGEN FIXATION AND YIELD OF COWPEAS (VIGNA UNGUICULATA (L.) WALP.).

MOHAMED, IBRAHIM ELBASHIR. January 1985 (has links)
The responses of two cowpea (Vigna unguiculata (L.) Walp.) cultivars inoculated with granular inoculum (a mixture of rhizobia) at different levels of applied nitrogen were evaluated. California Blackeye 5 (Ca5) and Knuckle Purple Hull (KPH) cowpeas were examined under field conditions for percent nodulation, nodule number, and nodule mass per plant, and nitrogenase activity at various times during the 1983 and 1984 growing seasons. Data were also obtained for shoot and root dry weights, seed yield, and protein content. Significant differences between inoculated and uninoculated plots were found at all nitrogen treatments for both cultivars with respect to nodulation percentage, nodule number, nodule mass, and nitrogenase activity. An inverse trend linear and quadratic was noted between nitrogen increments and nodulation (nodule number and nodule mass) of Ca5 and KPH cowpeas. High N (168 kg N ha('-1)) was more inhibitory to nodulation than low (28 kg N ha('-1)) N applied. Nitrogenase activity of both cultivars was significantly stimulated with low and inhibited by high levels of ammonium nitrate. Effects of nitrogen treatments on nodulation and nitrogenase activity were influenced by the stage of growth and cowpea cultivar. At the pod-fill stage, higher nodule numbers and nitrogenase activity were recorded for Ca5 as compared to KPH cowpeas. Morphological differences, with Ca5 plants being erect with few vines, whereas KPH plants were semi-erect and bushy, were observed between inoculated and uninoculated plants of Ca5 and KPH cowpeas at all levels of applied nitrogen. Dry weights of vegetative components of both cultivars were significantly improved when low (28 kg N ha('-1)) rather than high (168 kg N ha('-1)) nitrogen was added. Inoculation significantly increased seed yield of Ca5 cowpeas. When conditions were favorable seed yield of inoculated Ca5 exceeded that of inoculated KPH in all comparisons within the same increments of applied N. Seed yield of both cultivars was adversely affected when high levels of nitrogen were applied. Seed, leaf, petiole, and stem protein content were significantly higher with respect to inoculated than uninoculated plots. However, nitrogen fertilizers tended to decrease protein content of the measured parameters for Ca5 and KPH cowpeas.
83

Soil nitrogen forms and mobility in relation to crop response

Turjoman, Abdul-Mannan January 1960 (has links)
No description available.
84

Slow release vs. fast release sources of nitrogen : effects on soil nitrogen content and corn growth.

Miller, Percy L. January 1973 (has links)
No description available.
85

The investigation of the role of Biejerinckia and Klebsiella as nitrogen fixers in stream litter decomposition

Vyas, Dilipkumar V. January 1980 (has links)
The role of Beijerinckia spa and Klebsiella spp in stream litter decomposition was investigated using acetylene reduction method. Beijerinckia and Klebsiella were isolated during the winter and spring of 1980, from the leaves of sugar maple (Acer Saccharum), placed in Bell Creek, Muncie, Indiana. A nitrogen-free media was used to isolate Klebsiella. Both of these organisms were streaked separately on nitrogen-free agar slant tubes, flushed with argon and acetylene added. Gas chromatographic analysis were conducted on the innoculated tubes after incubation for 24 hours at 320 C. Beijerinckia spp, isolated from January, February, and April fixed between 4.48 x 10-7 moles and Klebsiella spp isolated during the same time period was between 1.47 to 8.10 x 10-8 moles. This study indicates that Beijerinckia is a better N2 fixer than Klebsiella in stream litter decomposition.
86

The economics of nitrogen fertilizer cutbacks to reduce potential ground water contamination : a case study of selected Arizona crops /

Selig, Margot Littman, January 1992 (has links) (PDF)
Thesis (M.S. - Agricultural and Resource Economics)--University of Arizona. / Includes bibliographical references (leaves 145-152).
87

The impact of nitrogen and phosphorus concentration and N/P ratio on cyanobacterial dominance and N₂ fixation in some Estonian lakes /

Tõnno, Ilmar. January 1900 (has links) (PDF)
Thesis (doctoral)--University of Tartu, 2004. / Includes bibliographical references.
88

Some enzymatic aspects of nitrogen metabolism in regenerating liver

Kim, Sangduk. January 1960 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1960. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
89

Effect on the nitrogen balance of men of varying the source of essential and of non-essential amino acids

Heindel, Mary Belle (Krecker), January 1968 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1968. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
90

Nitrogen Metabolism of College Women on Self-Selected Diets

Boshart, Gayle Jewel January 1947 (has links)
The purpose of the present study is to determine the nitrogen intake and output (in both urine and feces) of two groups of Texas college women living in the Home Management House at North Texas State College.

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