A study was made of the phosphorus ecology of the Swale - Ouse river in northern England. It ranges from a stream draining a peat moorland to a mature river influenced by urbanisation (estimated population 250 000) and intensive agriculture. The aims were to assess the concentration and variability of aqueous N and P on spatial and temporal scales, and the response of two common mosses, Fontinalis antipyretica and Rhynchostegium riparioides, to those changes. Key aspects included analysis of water chemistry, internal nutrient contents of mosses, and 'surface' phosphatase activity. The rate of activity of m situ plants was measured over an annual period, in conjunction with short-term studies of transplanted populations. Studies of phosphatase activity in the water also were carried out to assess the biological cycling of phosphorus. Aqueous total phosphorus and total dissolved nitrogen concentration increased on passing down the river. In the upper reaches, total phosphorus comprised equal contributions of dissolved organic and inorganic phosphorus, which were almost certainly derived from diffuse sources. Further downstream, total phosphorus was almost entirely comprised of inorganic phosphorus from point source inputs. The nitrogen and phosphorus content of Fontinalis antipyretica and Rhynchostegium riparioides increased on passing downstream, consistent with the water chemistry. The rate of phosphomonoesterase activity of both mosses was high in the upper reaches of the river, and was inversely related to nutrient content. Fontinalis antipyretica sampled from streams draining peat moorland was shown to have a high phosphodiesterase : phosphomonoesterase ratio. A possible explanation for this is that peat is a potentially rich source of phosphodiester substrate, although increased phosphodiesterase activity may be a response to extreme phosphorus limitation. Transplantation of F. antipyretica showed that internal nutrient content and phosphatase activity respond to changes in ambient nutrients. Aqueous phosphomonoesterase activity was studied over a 12-month period. Laboratory and field studies suggest it plays an important role in the. phosphorus dynamics of the Swale - Ouse river system.

Call number: LD2668 .T4 1950 G4 / Master of Science

Thesis advisor: Noah P. Snyder / Estimating annual phosphorus (P) loading in impaired fresh water bodies is necessary to identify and prioritize management activities. A variety of monitoring programs and water quality models have been developed to estimate P loading in impaired watersheds. However, uncertainty associated with annual riverine P loads tends to receive less attention. This study addresses this gap by exploring the range in annual total phosphorus (TP) loads from two common load estimation methods using data collected in the Charles River watershed (CRW) in eastern Massachusetts. The CRW has two P Total Maximum Daily Load (TMDL) reports due to impairments with respect to excessive summer algal growth. Three estimation methods are used in this thesis to quantify annual TP loads (LY): the concentration-discharge relationship (CQ), the land use coefficient (LUC) method, and the average concentration, continuous discharge (ACQ) method. LY derived using the LUC method spanned an average relative percent range of 214% at each site, whereas LY results from the concentration-discharge method spanned an average relative percent range of 56%. While results of the CQ method produced a narrower range of LY, the CQ relationship is subject to seasonal dependencies and inconsistency through time. Seasonal terms in the LOADEST program, a publicly available and commonly used statistics tool, do allow the model estimates to capture trends through time, an advantage over the LUC method. Results of an interlaboratory comparison of P concentrations demonstrate the potentially large role of analytical uncertainty in LY estimation. Significant discrepancies between the results of each method for a single location and time suggest that loading estimates and consequently management priorities may be dependent on the estimation technique employed. / Thesis (MS) — Boston College, 2018. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Earth and Environmental Sciences.

pt I. Heterobimetallic complexes of PPh2, trans-(CO)3Fe(Ph2Ppy)2 and trans-(CO)3Fe(Ph2Ppym)2 -- pt II. Metal complexes of tertiary phosphine betaines. / by Song-Lin Li. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 77-83, 167-173). / Acknowledgments / Abstract --- p.i-ii / Table of Contents --- p.iii-iv / Structural Formulas of Ligands --- p.v / Index of Compounds --- p.vi-vii / List of Tables --- p.viii-ix / List of Figures --- p.x-xii / Chapter Part I. --- " HeterobimetaUic Complexes of PPh2-, trans- (CO)3Fe(Pli2Ppy)2 and trans-(CO)3Fe(Ph2Ppym)2" --- p.1 - 83 / Chapter 1. --- Introduction --- p.1-11 / Chapter 2. --- Results and Discussion / Chapter 1. --- "Synthetic and Structural Characterization of the Phosphido-Bridgcd Heterobimetallic Transition Metal Complex, (OC)3Fe(μ-PPh2)2Mo(CO)4" --- p.12-18 / Chapter 2. --- ############################################################################################################################################################################################################################################################### --- p.19-36 / Chapter 3. --- Coordination Chemistry of a New Neutral Organomctallic Tridcntate Ligand trans-(CO)3Fe(Ph2Ppym)2 (Ph2Ppym = 2-(di --- p.37-76 / Chapter 1. --- Synthesis and Crystal Structure of trans-(CO)3Fe(Ph2Ppym)2 --- p.38-42 / Chapter 2. --- "Mono-, Di- and Tridcntate Coordination Modes of trans-(CO)3Fe(Ph2Ppym)2 Towards Mercury(II) Halide/Pscudohalide" --- p.42-52 / Chapter 3. --- "Synthesis and Crystal Structures of Complexes Containing an Fe→Cd Donor-Acceptor Bond Formed by Reaction of trans-(CO)3Fe(Ph2Ppym)2 with CdX2 (X = C1, Br, I，SCN, C1O4)" --- p.53-65 / Chapter 4. --- "Miscellaneous: Interaction of trans-(CO)3Fe (Ph2Ppym)2 with Hg2(ClO4)2.xH2O，[(cod)RhCl]2, (cod)PdCl2, PdCl2 and Nd(SCN)3 .xH2O" --- p.66-76 / References --- p.77-83 / Chapter Part II. --- Metal Complexes of Tertiary Phosphine Betaines --- p.84-173 / Chapter 3. --- Introduction --- p.84-96 / Chapter 4. --- Results and Discussion / Chapter 1. --- Betaine Derivatives --- p.97-109 / Chapter 2. --- Cadmium(II) Complexes with Tertiary Phosphine Bctaincs --- p.110-145 / Chapter 1. --- """Paddle wheel-like"" cadmium(II) complexes" --- p.111-116 / Chapter 2. --- "Discrete Mono-, Bi-, Tri- and Tctra-nuclcar Complexes of Cadmium(II) with Ph3P+(CH2)2CO2-" --- p.116-129 / Chapter 3. --- A Layer-Type Complex of Cadmium(II) Chloride/Pcrchlorate with Triphenylphosphoniopropionate (Ph3P+(CH2)2C02 -) --- p.130-133 / Chapter 4. --- A Layer-Type Complex of Cadmium(II) Chloride/Pcrchlorate with Triphenylphosphoniopropionate (Ph3P+(CH2)2C02-) --- p.134-139 / Chapter 5. --- Mixed-ligand Cadmium(II) Complexes of Ph3P(CH2)2CO2- and Me2N(CH2)2NMe2 (tmen) --- p.139-144 / Chapter 3. --- Zinc(II) and Mercury(II) Complexes --- p.146-155 / Chapter 1. --- Synthesis and Structural Characterization of Mono- and Dinuclcar Zinc(II) Complexes of Triphenylphosphoniopropionate --- p.146-151 / Chapter 2. --- Interaction of Mercury(II) Halidcs with Tertiary Phosphine Bctaines --- p.151-155 / Chapter 4. --- "Cobalt(II), Copper(II) and Silver(I) Complexes" --- p.156-166 / References --- p.167-173 / Chapter 5. --- Conclusion --- p.174-178 / Chapter 6. --- Experimental --- p.179-203 / Appendix A Table of Atomic Coordinates and Thermal Parameters --- p.204-226 / Publications based on results reported in this thesis --- p.227-228

Sze Wing Yin. / Thesis submitted in: November 2005. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references. / Abstracts in English and Chinese. / Table of Contents --- p.vi / Acknowledgements --- p.i / Abstract --- p.ii / 摘要 --- p.iv / List of Compounds Synthesized --- p.x / Abbreviation --- p.xi / Chapter Chapter 1 --- Syntheses and Characterization of Bis(phosphoranoimido)lithium and Late Transition Metal Complexes / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.1.1 --- A General Review of Bis(Phosphoranoimido) Ligands --- p.1 / Chapter 1.1.2 --- Synthesis of Bis(Phosphoranoimido)metal Complexes --- p.8 / Chapter 1.2 --- Objectives --- p.13 / Chapter 1.3 --- Results and Discussion --- p.14 / Chapter 1.3.1.1 --- "Synthesis of Bis(Phosphoranoimido)lithium complexes [Li{{(Me3SiNPR2CH)(Me3SiN=PR2CH2)}C5H3N-2，6} (R = Ph, 36; R = Pr', 37)]" --- p.14 / Chapter 1.3.1.2 --- Spectroscopic Properties of Complexes 36 and 37 --- p.14 / Chapter 1.3.1.3 --- "Molecular Structures of [Li{{(Me3SiNPR2CH)- (Me3SiN=PR2CH2)}C5H3N-2,6} (R = Ph, 36; R = Pr', 37)]" --- p.16 / Chapter 1.3.2.1 --- Synthesis and Characterization of Bis(Phosphoranoimido)transition Metal Complexes --- p.21 / Chapter 1.3.2.2 --- Spectroscopic Properties of 38 - 41 --- p.21 / Chapter 1.3.2.3 --- "Molecular Structures of [MCI {{(Me3SiNPPh2CH)- (Me3SiN=PPh2CH2)}C5H3N-2,6}] (M = Co, 38; Mn, 39)， [MnCl{{(Me3SiNPPri2CH)(Me3SiN=PPri2CH2)}C5H3N-2，6}] (41)" --- p.22 / Chapter 1.4 --- Experimental Section --- p.31 / Chapter 1.5 --- References for Chapter 1 --- p.36 / Chapter Chapter 2 --- Syntheses and Characterization of Bis(phosphoranoimido)zirconium(IV) Complex / Chapter 2.1 --- Introduction --- p.39 / Chapter 2.1.1 --- General Aspects of Group 4 Metal Complexes --- p.39 / Chapter 2.2 --- Results and Discussion --- p.44 / Chapter 2.2.1 --- "Synthesis and Characterization of Bis(phosphoranoimido)zirconium(IV) Complex [Zr{(Me3SiNPPh2C)(Me3SiN=PPh2CH2)C5H3N-2,6}(NMe2)2] (46)" --- p.44 / Chapter 2.2.2 --- Reaction of Bis(phosphoranoimido)zirconium(IV) Complex (46) with HC1 --- p.45 / Chapter 2.2.3 --- Spectroscopic Properties of Complex 46 --- p.45 / Chapter 2.2.4 --- Molecular Structure of [Zr{(Me3SiNPR2C)- (Me3SiN=PR2CH2)5H3N-2，6}(NMe2)2] (46) --- p.46 / Chapter 2.3 --- Experimental Section --- p.51 / Chapter 2.4 --- References for Chapter 2 --- p.52 / Chapter Chapter 3 --- Syntheses and Characterization of Bis(phosphoranoimido)samarium(III) Complexes / Chapter 3.1 --- Introduction --- p.54 / Chapter 3.1.1 --- A General Review of Lanthanide Complexes --- p.54 / Chapter 3.1.2 --- General Aspect of Bis(phosphoranoimido)lanthanide Metal Complexes --- p.58 / Chapter 3.1.3 --- Synthesis and Structure of Bis(phosphoranoimido)dilithium Complex --- p.60 / Chapter 3.2 --- Results and Discussion --- p.63 / Chapter 3.2.1 --- Synthesis and Characterization of Bis(phosphoranoimido)samarium(III) Complexes --- p.63 / Chapter 3.2.2 --- Spectroscopic Properties of 56 and 57 --- p.65 / Chapter 3.2.3 --- "Molecular Structures of [Sm {{(Me3SiNPPh2CH)2} - C5H3N-2，6}(μ-Cl2)Li(THF)2] (56) and [Sm{{(Me3SiNPPri2CH)2}C5H3N-2,6}2(μ-Cl)]2 (57)" --- p.65 / Chapter 3.3 --- Experimental Section --- p.72 / Chapter 3.4 --- References for Chapter 3 --- p.74 / Appendix I / Chapter A. --- General Procedures --- p.77 / Chapter B. --- Physical and Analytical Measurements --- p.77 / Appendix II / Table A.1. Selected Crystallographic Data for Compounds 36，37 and 38 --- p.80 / Table A.2. Selected Crystallographic Data for Compounds 39，41 and 46 --- p.81 / Table A.3. Selected Crystallographic Data for Compounds 56 and 57 --- p.82

This thesis presents an experimental study, both in the field and laboratory to cast more light on the primary role of the river floodplains in releasing and/or removing total-P to/from the in-stream load, under high runoff and flood conditions, by investigating the soil total-P spatial and vertical deposition patterns and topsoil erodibility, along the three (3) main river sections (e.g., headwaters, transfer and deposition zones) of an agricultural watershed, such as the Turkey River (TR). In soils, phosphorus, P, primarily exists as sediment-bound and less often as dissolved. During wet hydrological years, soil erosion and surface runoff are the main P release and transport mechanisms, while during dry hydrological years, P leaches to the deeper soil levels and is transported to freshwaters through groundwater discharge. In between the upland areas and the river network, there is a buffer zone, known as floodplain that regulates the flux exchanges between these two watershed components. Floodplains play an essential role in the riverine system health by supporting important physical and biochemical processes and improving the water quality downstream. These characteristics have led to the conclusion that floodplains primarily act as sinks for P. However, floodplains are subject to erosion as well, where soil particles along with the attached P are removed from the topsoil or enter re-suspension, under high runoff and flood conditions. The study provides an insight into the soil total-P deposition patterns across the floodplains of five (5) identified field sites and couples them with topsoil erodibility to eventually address the research objectives, which can be summarized as follows: (i) investigation of the soil total-P spatial and vertical variability across the floodplains along the main river zones and development of relationships between P variability and soil physical properties (e.g., soil texture); (ii) identification and characterization of the soil total-P deposition patterns across the floodplains (e.g., short- vs. long-term P deposition areas); and (iii) comparisons of the soil total-P concentrations and critical shear stresses among the main river zones and determination of their primary function either as P sources or sinks, under high runoff and flood conditions. Following that line of thinking, this research results comprise of three (3) parts, each one addressing a specific objective. The first part of the results includes the soil texture and total-P concentration analyses of the extracted soil profiles to identify the soil total-P spatial and vertical deposition patterns across the floodplains, as well as, to investigate the total-P variability with respect to soil physical properties (e.g., soil texture). The second part of the results focuses on investigating the role of topography (e.g., flat vs. ridge vs. swale land surfaces) and flood characteristics (e.g., frequency, magnitude, duration) in soil total-P spatial and vertical deposition patterns across the river floodplains to understand the time-scale nature of the P storage. The last part of the results presents the experimentally determined topsoil critical shear stress values and erodibility rates to characterize the floodplains’ primary function, based on their location along the three (3) main river zones, either as sources or sinks for total-P, during high runoff and flood conditions. Overall, the results of this research show that (i) the total-P concentration in soils is tightly related to the fine particle content and monotonic linear relationships can be established between the two variables. In other words, the higher the fine particle content, the higher the total-P concentration in soils; (ii) a mixture of two normal distributions fit the log-transformed soil total-P concentration data of each field site considered in this study. The fitted distributions successfully capture the two peaks of the soil total-P concentration data correspond to the lower and upper floodplain terraces; (iii) the lower floodplain terraces (e.g., 2- and 5-year floodplains) are characterized by significantly lower soil fine particle percentage contributions and total-P concentrations compared to the upper floodplain terraces, at a 5% confidence level. These patterns can be attributed to the fact that the lower floodplain terraces are frequently flooded and/or under inundation compared to the upper floodplain terraces and thus part of the fine particles along with the attached P are regularly winnowed away. Therefore, the lower floodplain terraces can be considered as short-term P storage means, in between two consecutive major flood events, while the upper floodplain terraces act more as long-term P storage means; (iv) there is a longitudinal increase in the topsoil critical shear stress values, which follows the increase in the fine particle content reconfirming the principle that the more the fine particle content in soils, along with the existence of vegetation with dense, well-developed root systems, the more resistant to erosion are the soils. From a soil erodibility perspective, the floodplains along the headwaters zone can be considered as major fine sediment and total-P sources contributing to the in-stream loads, while the floodplains along the deposition zone primarily act as sinks for fine sediment and total-P. As far as the role of the floodplains along the transfer zone, they can be considered as sinks for fine sediment and total-P during low magnitude runoff and flood events (e.g., 2-; 5-; and 10-year return periods), while during higher magnitude events, they act as sources releasing fine sediment and total-P; and (v) topsoil samples characterized by dense, well-developed root systems fall approximately along a trend line that follows almost a parallel pattern with the trend line for the topsoil samples without dense and/or well-developed root systems. The existence of dense, well-developed vegetation root systems to topsoil consistently increases its critical shear stress threshold (e.g., > 1 Pa) and thus its ability to resist erosion.

Excessive phosphorus (P) is one of the major pollutants in natural water that are responsible for algal blooms and eutrophication. P removal by soil and slag is an attractive solution if the P sorption capacity of soil or slag is significant. To design an efficient land treatment facility, basic information on the behaviour of P in the media-water environment is required. In this study, detailed experiments were conducted to study P removal under static and dynamic conditions, and mathematical models were developed to describe these processes. The kinetic studies on P sorption onto a sandy loam soil from North Sydney, Australia, and dust and cake waste products from the BHP steel industry revealed that P sorption is a slow process. More than 90% of the P was adsorbed within 70, 12 and 60 hours in a mixing system for soil, dust and cake respectively while it was within 240, 24 and 120 hours respectively in a static (no stirring) system. Dust adsorbed P the most, compared to the other adsorbents (220-225 times and 4-5 times of the sorptivity of soil and cake respectively). P sorption in the batch experiments was described better by an equation using the Langmuir isotherm than one using the Freundlich isotherm. The kinetics of P sorption were satisfactorily explained by a static, physical, non-equilibrium sorption model (SPNSM). The pH of the P solution played a critical role in the extent of removal and the removal mechanisms of P. Removal was at a minimum at pH 2. The effect of pH on P removal varied depending on the type of adsorbents and the initial P concentration. The dominant removal mechanism of P at pH<8 was physical sorption, while it was chemical precipitation at pH>10. Batch flocculation experiments revealed that the P removal efficiency increased with an increase of adsorbent dose, flocculation (contact) time and mixing rate. P sorption is affected by the presence of NH4 which competes for available sites on the adsorbents. The amount of P adsorbed by dust and cake in the presence of NH4 was less than that in a single solute system. The reduction percentage of P for dust ranged from 33 to 57%. Detailed column experiments conducted with soil, dust and cake as media indicated that dust and cake have much higher sorption capacities than soil. The solid phase P concentrations on dust and cake calculated from batch experimental isotherm constants are substantially higher than those estimated.

Modelling of phosphorus donor-based silicon (Si:P) qubit devices and mesoscopic single-electron devices is presented in this thesis. This theoretical analysis is motivated by the use of Si:P devices for scalable quantum computing. Modelling of Si:P single-electron devices (SEDs) using readily available simulation tools is presented. The mesoscopic properties of single and double island devices with source-drain leads is investigated through ion implantation simulation (using Crystal-TRIM), 3D capacitance extraction (FastCap) and single-electron circuit simulation (SIMON). Results from modelling two generations of single and double island Si:P devices are given, which are shown to accurately capture their charging behaviour. The trends extracted are used to forecast limits to the reduction in size of this Si:P architecture. Theoretical analysis of P2+:Si charge qubits is then presented. Calculations show large ranges for the SET measurement signal, Δq, and geometric ratio factor, α, are possible given the 'top-down' fabrication procedure. The charge qubit energy levels are calculated using the atomistic simulator NEMO 3-D coupled to TCAD calculations of the electrostatic potential distribution, further demonstrating the precise control required over the position of the donors. Theory has also been developed to simulate the microwave spectroscopy of P2+:Si charge qubits in a decohering environment using Floquet theory. This theory uses TCAD finite-volume modelling to incorporate realistic fields from actual device gate geometries. The theory is applied to a specific P2+:Si charge qubit device design to study the effects of fabrication variations on the measurement signal. The signal is shown to be a sensitive function of donor position. Design and analysis of two different spin qubit architectures concludes this thesis. The first uses a high-barrier Schottky contact, SET and an implanted P donor to create a double-well suitable for implementation as a qubit. The second architecture is a MOS device that combines an electron reservoir and SET into a single structure, formed from a locally depleted accumulation layer. The design parameters of both architectures are explored through capacitance modelling, TCAD simulation, tunnel barrier transmission and NEMO 3-D calculations. The results presented strengthen the viability of each architecture, and show a large Δq (> 0.1e) can be expected.

Much attention has been paid to the effects of anthropogenic impacts upon physical and chemical conditions in freshwater ecosystems. However, impacts upon the functioning of these ecosystems and services that they provide remain relatively unknown. The objective of this thesis was to examine the validity of the general hypothesis that the deterioration of ecosystems may be reflected in their capacity to process resources. Changes in stream phosphorus retention and metabolism were investigated across a rural-urban gradient in the Torrens River Catchment, South Australia, where channel structures of rural reaches are less modified than urban reaches. In a stream with an intact upper rural catchment (First Creek), a reach with an un-modified channel structure retained 60% ± 12.1 filterable reactive phosphorus (FRP) and had an average uptake length of 79 m ± 3.4. In comparison, degraded and engineered reaches of First Creek retained less FRP and had longer uptake lengths. In Fourth Creek, which is influenced by agriculture, there were no differences in FRP retention between the reaches. Reduced FRP retention in impacted reaches were a result of decreased contact time, reduced period of continuous flow and increased nutrient availability. Although abiotic benthic FRP uptake rates (up to 6.8 μg m [ superscript minus 2 ] s [ superscript minus 1 ] ± 0.36) were consistently greater than biotic uptake rates (up to 3.6 μg m [ superscript minus 2 ] s [ superscript minus 1 ] ± 0.52), decreased total benthic uptake rates in impacted reaches were mainly due to decreased biotic uptake. Metabolic rates were measured within benthic chambers containing rocks and gravel and scaled up to the stream reach. At chamber and reach scales, metabolic rates in the unmodified reach of First Creek were consistently low (community respiration (CR) up to 113 mg O [ subscript 2 ] m [ superscript minus 2 ] day [ superscript minus 1 ] ± 47.4 and gross primary production (GPP) up to 234 mg O [ subscript 2 ] m [ superscript minus 2 ] day [ superscript minus 1 ] ± 89.5), with a positive net ecosystem production (NEP). In comparison, the degraded reach of First Creek switched between having a negative and positive NEP. Reaches of Fourth Creek also experienced considerable variation and had higher metabolic rates than First Creek (CR up to 371 mg O [ subscript 2 ] m [ superscript minus 2 ] day [ superscript minus 1 ] ± 62.1 and GPP up to 847 mg O [ subscript 2 ] m [ superscript minus 2 ] day [ superscript minus 1 ] ± 66.1). Increased metabolic rates in impacted reaches were attributed to increased light availability and reduced grazing by higher trophic levels, promoting autotrophic organisms. The altered ecosystem functions were considered to reflect a reduced capacity of deteriorated streams to process resources. However, the addition of coarse particulate organic matter to a degraded-urban stream reach increased CR and reduced NEP to levels more akin to those experienced within pristine streams. Furthermore, percent FRP retention increased, primarily through increased demand for phosphorus of the microbial community. Although this demonstrated that rehabilitation of in-stream attributes might restore important ecosystem functions in impacted streams, successful restoration will only be achieved if the over-riding causes of in-stream degradation are addressed. / Thesis (Ph.D.)--School of Earth and Environmental Sciences, 2005.

xv, 130 leaves : ill. ; 26 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.1971) from the Dept. of Agricultural Biochemistry and Soil Science, Waite Agricultural Research Institute, University of Adelaide