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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.
31

Benaderings tot die sintese van stikstofringverbindings

Crous, Renier 29 May 2014 (has links)
M.Sc. (Chemistry) / Please refer to full text to view abstract
32

Synthesis of nitrogen containing heterocycles /

Burnett, Duane Arthur January 1986 (has links)
No description available.
33

Synthesis of bacterial protein and other nitrogenous compounds from urea by cellulolytic rumen bacteria in vitro /

Winter, Karl Angevine January 1962 (has links)
No description available.
34

Synthesis and properties of bridgehead-nitrogen bicyclic compounds /

Schickedantz, Paul David January 1959 (has links)
No description available.
35

Researches in the synthetic photochemistry of some nitrogen heterocycles /

Hyatt, John Anthony January 1973 (has links)
No description available.
36

Differential colorimetric determination of nitrite and nitrite ions in water

Zitomer, Fred. January 1960 (has links)
Call number: LD2668 .T4 1960 Z57
37

Nitrogen-phosphorus compounds produced from the vapor-phase reaction of ammonia and phosphorus pentoxide

MacDonald, Allan H. January 1961 (has links)
Call number: LD2668 .T4 1961 M32
38

The collection of products from the vapor-phase reaction of phosphorus, air, and ammonia

Dorawala, Tansukhlal G. January 1964 (has links)
Call number: LD2668 .T4 1964 D69 / Master of Science
39

I. Significant electronic effects in catalytic asymmetricepoxidation ; II. Peroxynitrite decomposition mediated by ketones andaldehydes

Chen, Jian, 陳健 January 2000 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
40

Metabolic differentation in the lichen Cladonia portentosa from different wet nitrogen deposition regimes

Freitag, Sabine January 2010 (has links)
The deposition of atmospheric nitrogen is now recognized as a major driver of biodiversity changes at mid to high latitudes. It has previously been shown that regional variations in wet nitrogen deposition in the British Isles are reflected in broad targeted chemical parameters in the common heathland lichen Cladonia portentosa. A more detail analysis of alterations in the metabolic pathways in Cladonia portentosa collected from different locations within the UK was undertaken by applying the environmental metabolomics approach. Fourier transform infrared spectroscopy (FTIR) and liquid chromatography mass spectrometry (LC-MS) were applied in combination with principal component analysis (PCA) and partial least squares regression analysis (PLSR). The latter statistical method was used to correlate measured variables with modelled atmospheric data including wet nitrogen deposition, nitrogen concentration and precipitation. While FTIR in combination with PCA and PLSR revealed signatures of broad metabolic classes, LC-MS in combination with PCA and PLSR allowed the identification of betaine lipids (BL) as potential biomarkers of nitrogen enrichment. A compound tentatively identified as monoacylglycerol-(N,N,N trimethyl)-homoserine (MGTS) showed the strongest positive relation to increasing wet nitrogen deposition regimes and consequent phosphorus deficiency. In contrast, the structurally related phosphatidylcholine containing a C18:2 ester showed the opposite trend in natural populations of C. portentosa. Results obtained for C. portentosa collected from the N manipulation site Whim Moss indicated that ammonium is causal for the increase of two of the identified betaine lipids in natural populations in C. portentosa. Betaine lipids as well as the phosphatidylcholine biomarker could potentially be used to monitor nitrogen regimes and resulting phosphorus limitation on the lichen C. portentosa. The approach used for this study represented an effective integration of the complementary analytical techniques of FTIR and LC-MS in combination with multivariate statistical tools for environmental metabolomic studies.

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