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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.
201

Movement of nitrate nitrogen in soil

Staicu, Irimie, 1905- January 1936 (has links)
No description available.
202

Ammonium ion fixation in soils

Postlethwaite, Marion Edgar. January 1949 (has links)
LD2668 .T4 1949 P61 / Master of Science
203

Preparation of Pyridinium and Diaminocarbonium Barbituric Acid Ylides

Douelle, Frederic 07 August 2003 (has links)
Through NMR experiments of the reaction of barbituric acid with carbodiimide, a general synthetic procedure for the preparation of 5-diaminomethylenebarbiturates (DABA) was developed. This procedure is very simple and applicable to the preparation of large quantities of DABA derivatives. Through the X-ray structural study of one of the DABA derivatives it was established that these compounds have a ylide-type structure with strong charge separation inside the molecule. 5-Ylide-pyridinium-methyl barbituric acid derivatives were investigated with the isolation of 4-dimethylamino-1-(2,4,6-trioxohexahydro- pyrimidin-5-ylide-methyl)-pyridinium as well as its corresponding 1,3- dimethylbarbituric acid derivative with quantitative yields. An alternative approach was attempted in order to prepare chiral 5-ylide-pyridinium-methyl-barbituric acid derivatives thus containing a chiral center between the charge separation. The extreme instability of the derivatives under investigation afforded the unique isolation of 4-dimethylamino-1- [(1,3-dimethyl-2,4,6-trioxo-hexahydro-pyrimidin-5-yl)-phenyl-methyl]-pyridinium in quantitative yield.
204

The role of uridylytransferase in the regulation of nitrogen control in Klebsiella pneumoniae

Edwards, Robert A. January 1994 (has links)
No description available.
205

A spectrophotometric method for the determination of ammonia ain water.

January 1975 (has links)
Jui Wen-chun. / Thesis (M.Phil.)--Chinese University of Hong Kong. / Bibliography: leaves 64-67.
206

Soil reactions of animal waste nitrogen

Reddy, Seelam Vijaya January 2010 (has links)
Digitized by Kansas Correctional Industries
207

Development of research platform for investigating nitrogen signalling in higher plants.

January 2003 (has links)
Chow, Cheung-ming. / Thesis submitted in: December 2002. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 149-155). / Abstracts in English and Chinese. / Thesis committee --- p.i / Statement --- p.ii / Abstract --- p.iii / Acknowledgement --- p.vi / General abbreviations --- p.viii / Abbreviations of chemicals --- p.ix / List of figures --- p.x / List of tables --- p.xiv / Table of contents --- p.xv / Chapter 1. --- Literature review --- p.1-26 / Chapter 1.1 --- General introduction of nitrogen metabolism in plants --- p.1 / Chapter 1.2 --- Interaction between nitrogen metabolism and other metabolic and developmental pathways in plants --- p.2 / Chapter 1.2.1 --- Carbon metabolism --- p.2 / Chapter 1.2.2 --- Development --- p.2 / Chapter 1.2.3 --- Flowering --- p.3 / Chapter 1.3 --- Metabolic signalling in plants --- p.5 / Chapter 1.3.1 --- Nitrogen signalling in plants --- p.5 / Chapter 1.3.1.1 --- Inorganic N signalling --- p.5 / Chapter 1.3.1.2 --- Organic N signalling --- p.6 / Chapter 1.3.2 --- Carbon signalling --- p.7 / Chapter 1.3.2.1 --- Signalling pathways --- p.7 / Chapter 1.3.2.2 --- Gene expression regulated by sugar --- p.8 / Chapter 1.3.2.3 --- Role of sugar signalling in growth and development --- p.9 / Chapter 1.4 --- Ways to elucidate a new signal transduction pathway --- p.10 / Chapter 1.4.1 --- Carbon signalling as a paradigm to provide hints for exploring nitrogen signalling in plants --- p.10 / Chapter 1.4.2 --- Designing long-term approach to tackle nitrogen signalling in plants --- p.14 / Chapter 1.5 --- "Molecular tools available to change the ""signal"" and the proposed ""sensor""" --- p.15 / Chapter 1.5.1 --- ASN1 overexpressing lines (35S-ASN1) --- p.15 / Chapter 1.5.2 --- PII overexpressing lines (PII ox) & PII truncated lines (PII trunc.) --- p.16 / Chapter 1.5.2.1 --- Plant PII and its possible role --- p.16 / Chapter 1.5.2.2 --- Nitrogen/carbon sensing as the proposed in vivo function of PII-like protein in Arabidopsis thaliana by the in planta bioassay of PII overexpressing (PII ox) lines --- p.17 / Chapter 1.5.2.3 --- Changes in physiological and transcriptional expression of nitrogen assimilatory genes in PII transgenic lines --- p.17 / Chapter 1.6 --- Review on nitrogen controls and sensing mechanism of microbial organism and higher plants --- p.21 / Chapter 1.6.1 --- Nitrogen sensing in enteric bacteria --- p.21 / Chapter 1.6.2 --- Nitrogen sensing in cyanobacteria --- p.21 / Chapter 1.6.3 --- Nitrogen sensing in fungi --- p.22 / Chapter 1.6.4 --- Implication of the nitrogen sensing mechanisms in microorganisms to nitrogen sensing in plants --- p.23 / Chapter 1.7 --- "Hypothesis, objectives and outlines of this thesis work" --- p.25 / Chapter 2 --- Materials and Methods --- p.27-50 / Chapter 2.1 --- Materials --- p.27 / Chapter 2.1.1 --- "Plants,bacterial strains and vectors" --- p.27 / Chapter 2.1.2 --- Chemicals and Regents --- p.28 / Chapter 2.1.3 --- "Buffer, solution and gel" --- p.28 / Chapter 2.1.4 --- Commercial kits --- p.28 / Chapter 2.1.5 --- Equipments and facilities used --- p.29 / Chapter 2.1.6 --- Growth medium --- p.29 / Chapter 2.1.7 --- Primers --- p.29 / Chapter 2.2 --- Methods --- p.29 / Chapter 2.2.1 --- Growth condition for plant materials --- p.29 / Chapter 2.2.1.1 --- General conditions --- p.29 / Chapter 2.2.1.2 --- Mature Arabidopsis for gene expression profile --- p.30 / Chapter 2.2.1.3 --- Arabidopsis seedlings for physiological experiment --- p.30 / Chapter 2.2.2 --- Molecular Techniques --- p.31 / Chapter 2.2.2.1 --- Bacterial cultures for recombinant DNA --- p.31 / Chapter 2.2.2.2 --- Preparation of pBluescript II KS(+) T-vector for cloning --- p.31 / Chapter 2.2.2.3 --- Cloning techniques --- p.32 / Chapter 2.2.2.4 --- Transformation of DH5a competent cell --- p.32 / Chapter 2.2.2.5 --- Gel electrophoresis --- p.33 / Chapter 2.2.2.6 --- DNA and RNA extractions from plant tissues --- p.34 / Chapter 2.2.2.7 --- First strand cDNA synthesis --- p.35 / Chapter 2.2.2.8 --- PCR techniques --- p.35 / Chapter 2.2.2.9 --- Sequencing --- p.37 / Chapter 2.2.3 --- Analysis of sequences and homology search --- p.37 / Chapter 2.2.4 --- Biochemical analysis --- p.41 / Chapter 2.2.4.1 --- Sugar content analysis --- p.41 / Chapter 2.2.4.2 --- Anthocyanin content analysis --- p.42 / Chapter 2.2.4.3 --- Fresh weight measurement --- p.43 / Chapter 2.2.4.4 --- Statistic analysis --- p.43 / Chapter 2.2.5 --- Generation of crossing progenies --- p.44 / Chapter 2.2.5.1 --- Artificial crossing of A. thaliana --- p.44 / Chapter 2.2.5.2 --- PCR screening for successful crossing --- p.44 / Chapter 2.2.6 --- Construction of subtractive libraries --- p.45 / Chapter 2.2.7 --- Reverse-dot blot screening --- p.45 / Chapter 2.2.7.1 --- in vitro transcription for making ampicillin cRNA --- p.46 / Chapter 2.2.7.2 --- PCR amplification --- p.47 / Chapter 2.2.7.3 --- Dot-blotting of PCR products on nylon membrane --- p.48 / Chapter 2.2.7.4 --- P probe preparation --- p.49 / Chapter 2.2.7.5 --- Hybridization --- p.49 / Chapter 2.2.7.6 --- Signal detection --- p.50 / Chapter 3 --- Results --- p.51-124 / Chapter 3.1 --- Differential growth behaviour and sugar content in 35S-ASNI lines --- p.51 / Chapter 3.1.1 --- Growth of the seedlings of 35S-ASN1 lines under different N and C supplementations --- p.51 / Chapter 3.1.2 --- Lowered reducing sugar content in 35S-ASN1 lines --- p.52 / Chapter 3.2 --- Development of markers for nitrogen signalling events related to altered N status in 35S-ASN1 lines --- p.60 / Chapter 3.2.1 --- Sugar-induced anthocyanin levels as common morphological marker shared by 35S-ASN1 lines and PII transgenic lines --- p.60 / Chapter 3.2.2 --- Expression markers related to altered N status in 35-ASN1 lines --- p.64 / Chapter 3.3 --- Generation of transgenic plants constitutively expressing ASN1 and GLB1 (or ASN1 and truncated GLB1) through crossing --- p.74 / Chapter 3.4 --- Search for homologs of well-known microbial nitrogen signalling components in Arabidopsis thaliana --- p.78 / Chapter 3.4.1 --- Homologs of yeast general amino acid control components --- p.80 / Chapter 3.4.1.1 --- Arabidopsis thaliana GCN2-like protein --- p.80 / Chapter 3.4.1.2 --- Arabidopsis thaliana GCN1 -like protein --- p.84 / Chapter 3.4.1.3 --- Arabidopsis thaliana GCN20-like protein --- p.84 / Chapter 3.4.1.4 --- Plant eIF2α --- p.86 / Chapter 3.4.1.5 --- Arabidopsis thaliana GCN4-CRE like sequences --- p.87 / Chapter 3.4.2 --- Homologs of fungi nitrogen sensing components: Globally acting factor in nitrogen control in fungi --- p.89 / Chapter 3.4.3 --- Homologs of cyanobacteria nitrogen control components: IF7 & IF 17 (Negative regulators of GS activity) --- p.89 / Chapter 4 --- Discussion --- p.125-147 / Chapter 4.1 --- Differential physiological and morphological behaviours found in the comparative studies between control lines and 35S-ASN1 lines --- p.125 / Chapter 4.1.1 --- in planta promotive effect of ASN1 overexpression on the seedlings growth under low nitrogen and in the absence of exogenous applied metabolizable sugar --- p.125 / Chapter 4.1.2 --- Modulation of sugar level in 35S-ASN1 lines --- p.126 / Chapter 4.2 --- Development of morphological marker and gene expression markers --- p.128 / Chapter 4.2.1 --- Anthocyanin accumulation as a morphological marker for epistatic analysis --- p.128 / Chapter 4.2.2 --- Differential expressed genes as candidates for gene expression markers of nitrogen signalling event --- p.131 / Chapter 4.3 --- Arabidopsis homolog search for well-known microbial signalling components --- p.132 / Chapter 4.3.1 --- "Possible amino acid sensing system in Arabidopsis constructed by homologs of yeast GCN2, GCN1, GCN20 and eIF2a" --- p.132 / Chapter 4.3.1.1 --- Arabidopsis GCN2-like (A. thaliana GCN2-like) protein --- p.132 / Chapter 4.3.1.2 --- Arabidopsis GCNl-like (A. thaliana GCNl-like) & GCN20-like (A. thaliana GCNl-like) proteins --- p.136 / Chapter 4.3.1.3 --- Plant eIF2a phosphorylation pathway --- p.139 / Chapter 4.3.1.4 --- GCN4 related transcriptional factors and GCN4-like motif (GLM) cis-element in plants --- p.140 / Chapter 4.3.1.5 --- Implication of the presence of plant homologs of fungi regulatory proteins involved in the general control of amino acid biosynthesis --- p.142 / Chapter 4.3.2 --- Failure in identifying homologs of nitrogen regulators responsible for switching of nitrogen source in Arabidopsis --- p.144 / Chapter 4.4 --- Overview of research platform construction --- p.146 / Chapter 5 --- Conclusion and Perspectives --- p.148 / Chapter 6 --- References --- p.149-155 / Chapter 7 --- Appendix --- p.156-167
208

Preparation and characterization of NdSrCu1-xCoxO4 and SM1.8Ce0.2Cu1-xCoxO4 catalysts for NOx decomposition.

January 2003 (has links)
Chan Yan Chi Rosa. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 70-71). / Abstracts in English and Chinese. / Abstract --- p.i / 論文摘要 --- p.ii / Acknowledgements --- p.iii / Table of Contents --- p.iv / List of Tables --- p.vii / List of Figures --- p.viii / Chapter Chapter 1. --- Introduction / Chapter 1.1 --- Nitrogen oxides --- p.1 / Chapter 1.1.1 --- NOx and their chemical and physical properties --- p.1 / Chapter 1.1.2 --- Sources and formation of NOx --- p.3 / Chapter 1.1.3 --- Evaluation of the impact of NOx on human health and environment --- p.4 / Chapter 1.2 --- Decomposition of NOx --- p.5 / Chapter 1.3 --- Perovskite-type oxides --- p.8 / Chapter 1.3.1 --- Structure and composition of perovsite-type oxides --- p.8 / Chapter 1.3.2 --- Preparation of perovskite-type oxides --- p.12 / Chapter 1.3.3 --- Literature review of perovskites for NOx decomposition --- p.14 / Chapter 1.4 --- Objective of the project --- p.16 / References --- p.17 / Chapter Chapter 2. --- Experimental / Chapter 2.1 --- Catalyst preparation --- p.20 / Chapter 2.2 --- Catalytic activity evaluation --- p.20 / Chapter 2.3 --- Catalyst characterization --- p.22 / Chapter 2.3.1 --- Powder X-ray diffraction (XRD) --- p.22 / Chapter 2.3.1.1 --- Theory --- p.22 / Chapter 2.3.1.2 --- Instrumentation --- p.23 / Chapter 2.3.2 --- "Brunauer, Emmett and Teller (BET)" --- p.26 / Chapter 2.3.2.1 --- Theory --- p.26 / Chapter 2.3.2.2 --- Experimental --- p.28 / Chapter 2.3.3 --- X-ray photoelectron spectroscopy (XPS) --- p.28 / Chapter 2.3.3.1 --- Theory --- p.29 / Chapter 2.3.3.2 --- Qualitative and quantitative analysis --- p.29 / Chapter 2.3.3.3 --- Instrumentation --- p.31 / Chapter 2.3.4 --- Thermogravimetric analysis (TGA) --- p.34 / Chapter 2.3.5 --- NO-temperature programmed desorption (NO-TPD) --- p.34 / Chapter 2.3.6 --- Titration method --- p.35 / References --- p.36 / Chapter Chapter 3. --- Preparation and Characterization of NdSrCu1-xCox04 and Sm1.8Ceo.2Cu1-xCox04 catalysts for NOx Decomposition / Chapter 3.1 --- Introduction --- p.38 / Chapter 3.2 --- Experimental --- p.39 / Chapter 3.3 --- Results --- p.40 / Chapter 3.3.1 --- "BET, XRD and chemical analysis studies" --- p.40 / Chapter 3.3.2 --- Catalytic activity --- p.43 / Chapter 3.3.3 --- XPS studies --- p.48 / Chapter 3.3.4 --- TGA and NO-TPD --- p.57 / Chapter 3.4 --- Discussion --- p.63 / Chapter 3.4.1 --- Catalytic performance --- p.63 / Chapter 3.4.2 --- Structural defects --- p.65 / Chapter 3.4.3 --- Oxidation states --- p.67 / Chapter 3.4.4 --- Copper ion redox ability --- p.68 / References --- p.70 / Chapter Chapter 4. --- Conclusion and Future Directions / Chapter 4.1 --- Conclusion --- p.72 / Chapter 4.2 --- Future directions --- p.73 / Chapter 4.2.1 --- Characterization of catalysts --- p.73 / Chapter 4.2.2 --- Reaction mechanism --- p.73 / Chapter 4.2.3 --- Variation of element in B-site --- p.74
209

Understanding and withstanding the decoherence of nitrogen-vacancy center spins in diamond. / 鑽石氮-空缺中心自旋的退相干研究及控制 / Understanding and withstanding the decoherence of nitrogen-vacancy center spins in diamond. / Zuan shi dan-kong que zhong xin zi xuan de tui xiang gan yan jiu ji kong zhi

January 2010 (has links)
Ho, Sai Wah = 鑽石氮-空缺中心自旋的退相干研究及控制 / 何世華. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 62-68). / Abstracts in English and Chinese. / Ho, Sai Wah = Zuan shi dan-kong que zhong xin zi xuan de tui xiang gan yan jiu ji kong zhi / He Shihua. / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- NV center in diamond --- p.6 / Chapter 2.1 --- Why NV centers? --- p.6 / Chapter 2.2 --- NV center --- p.8 / Chapter 2.3 --- Hamiltonian of the spin system --- p.11 / Chapter 3 --- Decoherence calculation - Cluster-correlation expansion --- p.13 / Chapter 3.1 --- The decoherence problem --- p.13 / Chapter 3.2 --- Quantum many-body theory: History and method --- p.17 / Chapter 3.3 --- General theory of cluster-correlation expansion --- p.19 / Chapter 3.4 --- Different physical processes and the pictorial understanding: Spin pathways in Bloch sphere --- p.21 / Chapter 3.4.1 --- Dynamical fluctuation versus inhomogeneous broadening --- p.21 / Chapter 3.4.2 --- Single nuclear spin dynamics --- p.22 / Chapter 3.4.3 --- Nuclear spin pair dynamics --- p.24 / Chapter 3.4.4 --- Higher order spin cluster dynamics --- p.27 / Chapter 4 --- Dynamical decoupling theories and experiments --- p.28 / Chapter 4.1 --- Dynamical decoupling: History --- p.28 / Chapter 4.2 --- Pulse sequences --- p.29 / Chapter 4.2.1 --- Spin echo (SE) --- p.30 / Chapter 4.2.2 --- Carr-Purcell-Meiboom-Gill (CPMG) sequence --- p.31 / Chapter 4.2.3 --- Concatenated dynamical decoupling (CDD) --- p.31 / Chapter 4.2.4 --- Uhrig dynamical decoupling (UDD) --- p.32 / Chapter 5 --- Dynamics of the spin clusters --- p.34 / Chapter 5.1 --- Convergence of CCE under external magnetic field and pulse sequence --- p.34 / Chapter 5.2 --- Zero magnetic field regime: single spin and spin pair induced dynamics --- p.35 / Chapter 5.2.1 --- Free induction decay --- p.36 / Chapter 5.2.2 --- Dynamical decoupling control: UDD1-5 --- p.37 / Chapter 5.3 --- Small magnetic field regime: Single spin and spin pair induced dynamics --- p.38 / Chapter 5.3.1 --- Single spin induced dynamics: single spin induced re- vivals under dynamical decoupling sequences --- p.38 / Chapter 5.3.2 --- Single spin induced dynamics: Periodicity of revivals un- der different dynamical decoupling sequences --- p.42 / Chapter 5.3.3 --- Single spin induced dynamics: Short time modulation and envelope under the effect of Fermi contact and dy- namical decoupling sequences --- p.45 / Chapter 5.3.4 --- "Single spin and spin pair induced dynamics: Revival, os- cillation and decay under dynamical decoupling sequences" --- p.48 / Chapter 5.4 --- Large magnetic field regime: Single spin and spin pair induced dynamics --- p.50 / Chapter 5.4.1 --- Free induction decay --- p.50 / Chapter 5.4.2 --- Dynamical decoupling control: UDD 1-5 --- p.52 / Chapter 6 --- Application: Atomic scale magnetometry --- p.55 / Chapter 7 --- Conclusion --- p.59 / Bibliography --- p.62 / Chapter A --- Derivation of modulation and envelope frequency using second order perturbation theory --- p.69
210

Effects of Nitrogen Fertilizer Rate, Timing, and Herbicide Use on Industrial Hemp (Cannabis Sativa)

Anderson, Robert David 01 April 2018 (has links)
Industrial hemp (Cannabis sativa) is an old crop being reintroduced into certain states; thus, very little information is known about growing the crop domestically. Two field experiments were established in Bowling Green, KY to evaluate various nitrogen fertilizer rates and timing applications to examine the effects on growth and yield of industrial hemp (Cannabis sativa). Each experiment was sprayed with 1.12 a.i. ha-1 pendimethalin on half of each plot as a pre – emergent herbicide. Hemp was planted at a rate of 43 kg/ ha into a conventionally tilled silt loam soil. Nitrogen rates studied were a control, 79, 157, and 236 kg N/ ha in the first experiment. In the second experiment, 157 kg N/ ha was applied at three timings along with a control. The three timings were: at establishment, side-dressed, and a split application of 78 kg at establishment and 78 kg side dressed. Plots were 6 m x 4.5 m and replicated 4 times for each experiment. Data collected included stand counts 34 days after planting (DAP), plant heights at 34 and 55 DAP, and stand counts, plant heights, fresh biomass, dried biomass, seed yield, and fiber yield at harvest (89 DAP) for both experiments. Increased fertilizer rates increased fresh and dried biomass which correlated with increased fiber yields. Different fertilizer timings had no effect on seed, biomass, or fiber yields. Herbicide had an early effect on stand counts and plant height in both experiments (

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