Customer Choice: What will it Take to Do it Right?

What are the most important building blocks needed to effectively deregulate energy markets? What are the forces driving deregulation? What problems and pitfalls have occurred and how can they be avoided? Will customer choice take off

Sediment Dispersion at the New Auckland Marine Disposal Ground, Northeast New Zealand

A controversial history of near shore dredged material disposal east of Auckland, New Zealand, starting in the mid-1980s, resulted in the use of a temporary deep water site that did not satisfy the requirements of the London Dumping Convention. In New Zealand, since most maintenance dredged material contains a low level of contamination, it is a common requirement that open-sea disposal sites are retentive, so that impacts can be monitored. In 2007, preliminary investigations for a proposed site located on New Zealand’s northeast shelf were initiated. Indications that the site was suitable prompted Maritime New Zealand (MNZ) to grant a permit for a trial disposal of 5,000 m3 of muddy dredged material on the condition that disposal operations were monitored to assess the potential for dispersion of the material beyond the boundary of the site. The overall aim for this thesis research, based on the questions raised by MNZ, was to determine the potential for dispersion at the AMDG and classify the site based on its dispersive qualities. This aim was approached in three ways: (i) investigation of the hydrodynamic setting, (ii) measurement of the disposal process and the resultant plume, and (iii) development and implementation of a model designed to simulate the disposal characteristics under conditions not observed in the field. The first two approaches involved measurement campaigns, which were undertaken in 2008 and 2010. The 2008 campaign primarily focused on investigation of the hydrodynamic setting through the deployment of a long-term upward facing ADP, which was complemented by hydrological measurements (CTD), and nearby wind records. The 2010 campaign corresponded to the trial disposals at the AMDG, where 4 disposals were monitored using a range of techniques. Stationary water sampling and OBS turbidity measuring stations were positioned in the vicinity of the disposal location with the intention of recording data that could be used to calibrate backscatter data recorded with a vessel mounted ADCP. These data were supplemented by additional pre- and post-disposal measurements, such as sediment cores, MBES backscatter, dynamic penetrometer profiles, and under water video imagery, which provided information on the depositional fate of the disposed material. Therefore, measurements were collected during all stages of the disposal process, providing a unique dataset for a deep-water disposal site. Due to the low number of published studies on disposal plume dispersal and the site specific nature of the process, it was not known in advance what the most efficient and practical techniques for monitoring the plume were. The identification of optimal measuring methods was a secondary outcome of this work. It was found that, due to the transient nature of the plume, stationary sampling techniques were not able to satisfactorily record the plume because its position was difficult to predict. Taking sequential measurements along transects proved to be the optimal approach for tracking the plume. Specifically, backscatter data from the vessel mounted ADCP records provided the best perspective on the spatial and temporal characteristics of the disposal plume. MBES bathymetry data recorded after the completion of all disposals was ultimately inconclusive regarding depositional fate because the deposits were less than 20 cm thick and, therefore, unresolvable at the water depths of the AMDG and the frequency of the system employed. However, a backscatter map, developed from the same MBES dataset, corroborated some of the findings from the plume monitoring surveys by showing the impact locations of the disposed loads, which appeared as lighter gray patches (higher density substrate) amongst the darker gray natural site sediment areas. Analysis of ADCP backscatter data obtained during the trial disposals indicated that the extent of horizontal dispersion was greatest in the surface region (500 800 m) due to stronger current velocities that occur as a result of the decreased influence of friction from the seabed and the increased influence of wind-driven currents. However, in all cases, after the descent of the dredged material to the seabed during the first few minutes, the maximum concentrations were always located near the seabed where horizontal dispersion was low (~200 m). Based on these findings, it was concluded that the weak ambient forcing mechanisms have the potential for the greatest dispersion, rather than the dynamic forces associated with the disposal process. It was found that while generally producing low ambient current velocities, the dominant forcing mechanisms at the AMDG were temporally variable, which could lead to a range of different dispersion characteristics. Tides, wind, and the East Auckland Current (EAUC) were identified as the predominant drivers. Tidal currents were relatively slow (2 10 cm/s), but in general appeared to be more important than wind-driven currents in the surface zone. The influence of the EAUC varied during the field campaigns, where its influence appeared to be weak during the monitored trial disposals, but strong during the long-term deployment of 2008. This variability corresponds to the findings of other studies undertaken on the dynamics of the northeast coast region. The short-term mechanisms of the disposal process, additionally captured in the ADCP backscatter records, showed similar characteristics to those previously described in the literature (i.e., 1 Convective Descent, 2 Dynamic Collapse, and 3 Passive Dispersion). However, through analysis of the rate of dilution throughout the 3 phases, an additional transitional phase was identified. This phase, observed both spatially (with distance from the disposal location) and temporally (with time after disposal), was characterised by a decreased rate of dilution. From the findings, an alternative conceptual model for the disposal process was developed in which the transitional phase was described as a turbulent zone, where water at the interface of the dynamic zone is set in circular motion, therefore, preventing dilution at a particular location or time. After momentum is reduced enough, the turbulent forces give way to the diffusive forces and passive dispersion becomes the dominant mode for dispersion. The main finding of this research was that the potential for dispersion beyond the boundary of the AMDG is low indicating that the site behaves retentively. This finding is partly a result of the low velocities of the ambient currents, but also because of the operational limitations of the tug-towed disposal method employed for disposal. For minimising the dispersion potential of the AMDG for future operations at the site, it is recommended that the disposal method remain unchanged, that material types more susceptible to dispersion not be disposed there, and that disposal not be undertaken when tidal currents are aligned with the wind direction for winds greater than 20 knots

Surface reactions of boron with clean tungsten substrates

A model developed to predict adsorbate-induced work-function changes for thermionic emitters is shown here to apply to a more general class of electron emission phenomena and a much broader range of adsorbates. This model predicts that chemically, vapor-deposited boron will increase the work function of a clean tungsten substrate at coverages between 0 and 1 monolayer. This is the first time that a single model has been shown to predict both positive and negative work function changes for different adsorbates. The reactions of chemically, vapor-deposited (CVD) boron with clean tungsten substrates were studied using field emission microscopy (FEM) and low energy electron diffraction (LEED). The studies by FEM indicate that boron nucleates in the vicinals of and grows across the central tungsten (110) plane. The single-spot, electron emission pattern thus formed is the result of a cap-shaped nucleus of boron which raises the local field strength in the (110) region by decreasing the local radius of curvature. The reversal of the emission characteristic of the clean tungsten (110) plane is not the result of submonolayer adsorption and therefore produces intense, confined electron emission which is independent of adsorption induced work function changes predicted by the general model. The FEM observations on and around the (100) planes are shown to correlate well with the general model showing a decreased emission (increased work function) with boron adsorption. The LEED study indicates that the CVD boron atoms on a clean tungsten (100) surface occupy epitaxial sites at coverages between 0 and 1 monolayer. These are the same sites that the next layer of tungsten atoms would occupy and represent the simplest potential minima available on the surface --Abstract, pages iii-iv

The Continental Shelf as a Site for Dredged Material Disposal, Northeast New Zealand

Disposal of dredged material has been an on-going problem in the Auckland Coastal Marine Area (CMA) since the early 1980s in New Zealand. Many disposal grounds have been established and used, but public concern over adverse effects resulted in their ultimate closure. Presently, dredged material is disposed off-shore at a site simultaneously accessed by the Royal New Zealand Navy for disposal of WWII munitions recovered from coastal areas. As early as the mid-1990s, parliamentary focus groups established the need for a more suitable disposal option for dredged material. Establishment of a disposal site north of Cuvier Island in waters deeper than 100 m was one of the key recommendations presented by these groups. The need for a new site was compounded after the establishment of the Hauraki Gulf Marine Park in 2000. Taking up the majority of the Auckland CMA this culturally significant Park makes the consent for open water disposal a complex process. A site east of Great Barrier Island in 140 m of water has been identified as a potential suitable site for disposal of dredged material. The main goal of the present study is to determine the suitability of this site and provide the necessary information required by enforcing authorities for permit submission. Investigations to determine the suitability of the site were undertaken in several ways. An extensive literature review of previous studies was carried out to gain insight into the physical and biological characteristics of the northeast coast and shelf. The main hydrodynamic features of the region and the observed behaviours were determined. Attentions were then directed at determining the more specific site characteristics. Analytical calculations were undertaken using known site parameters to estimate the potential for transport of sediment away from the site after disposal. Through analysis of known wave and current measurements it was estimated that only rarely would sediment be entrained off the seafloor. Samples were then collected from the site in November 2007, which were used for sediment textural analysis and benthic identification. It was determined that the main textural component of the site sediments is muddy/sand. Diversity of benthic species is relatively high, but abundance is low. Polychaetes were the most diverse and abundant taxon identified at sample locations across the site. Next, the 3DD model was used to numerically simulate 2-dimensional tidal currents. Depth-averaged spring tidal currents at the site were predicted to be less than 0.2 ms-1. The derived bottom velocity for such a current is 0.08 ms-1, which is much less than the velocity required for initiation of sediment movement in this case. The numerical simulation also showed that residual spring tidal flow is directed to the southeast. Finally, an assessment of potential impacts was done by reviewing previous studies of ecological impacts caused by disposal of dredged material. Based on the preliminary studies summarised above, the review of potential impacts indicates that there will only be minimal effects at and surrounding the proposed site. The result of this study is an encouraging step toward establishment of a new disposal option, but further research is required to confidently declare that the site is suitable for disposal operations

A Lamellar Liquid Crystal As An In Situ Surface Balance. I. The Conformation Of 5- (and 6-)carboxy-4-hexyl-2-cyclohexene-1-yl Octanoic Acid And Its Monosoap

The interfacial conformation of a dicarboxylic acid, 5- (and 6-)carboxy-4-hexyl-2-cyclohexene-1-yl octanoic acid, and its monosodium soap was determined from the change of liquid crystal dimensions after introduction of the diacid compounds. The results showed that both functional groups of the Mono soap form were present at the interface and that increased water content of the liquid crystal matrix had little effect on the conformation of the Mono soap. On the other hand, the results indicated the conformation of the diacid as such to depend on the water content of the matrix. At low water content, the diacid form was in a conformation similar to that found for the Mono soap. However, increasing the water content of the matrix resulted in a sharp decrease in the calculated partial molecular areas for the diacid, indicating an extended conformation for the diacid. © 1984

Establishment and production costs for commercial vineyards in Missouri

Cover title.Includes bibliographical references

Study of the Variations in Continuous Diesel Particulate Matter Size Measurements and Effect of Fuel Properties on DPM Size

Heavy-duty diesel engines (HDDE), because of their widespread use and reputation of expelling excessive soot, have frequently been held responsible for superfluous amounts of overall environmental particulate matter (PM). PM is a considerable contributor to air pollution, and a subject of primary concern to health and regulatory agencies worldwide. The U.S. Environmental Protection Agency (EPA) has provided PM emissions regulations and standards of measurement techniques since the 1980\u27s. PM standards set forth by the EPA for HDDEs are based only on total mass, instead of size and/or concentration. The European Union is considering regulating particle size, and it may influence the U.S. EPA to adopt particle size limits in the future.;The purpose of this research was to better understand the variations in DPM measurements due to fuel alteration or changes in other parameters such as relative humidity and dilution ratio. The Cambustion DMS-500, a fast particle spectrometer, was used to continuously sample diesel aerosol from a HDDE test-cell dilution tunnel. Samples were taken from the primary dilution tunnel and were further diluted in a secondary dilution system. Various fuels were selected to represent available market supplies. Three engines, a 2004 Cummins ISM 370, a 1992 Detroit Diesel DDC S60, and a rebuilt 1992 Detroit Diesel DDC S60, were tested to examine the effects of varying engine technology. Several types of biodiesel and petroleum-based diesel fuels were evaluated in these engines with and without additives. Experiments were performed to determine: the minimum detectable variations in PM concentrations, relative humidity effects, dilution effects, barometric pressure effects, fuel additive effects, sample line temperature effects, and the associations between certain engine operating events and PM concentrations.;The smallest significant variation in concentration that was detected during this research was a 1.51 % increase in 64 nm particles due to the use of a fuel additive. The effects of relative humidity on particle concentrations were only present during low load (less than 50 % of the maximum load) engine operation, and they were generally associated with high levels of run-to-run variation. Nearly doubling the overall dilution ratio was shown to greatly increase nanoparticle (\u3c40 nm) concentrations and slightly increase the concentrations of other particles during certain operation conditions. Barometric pressure change was not directly linked to PM emissions, but it appeared to have caused increased run-to-run variation. In all cases where a fuel additive was used, an increase in the amount of the additive led to a 130 % to -90 % change in the resulting particle concentrations. In addition, a technique was developed for the conversion of continuous DMS data (particle sizes and concentrations) to brake-specific PM mass-flow. According to the gravimetric measurements, the technique was accurate to within 6.24 % for the 1992 DDC S60 engines and 26.4 % for the 2004 ISM 370 engine

International agriculture : a world of opportunities

Cover title

Do endovascular filters prevent PE as effectively as anticoagulants in patients with DVT?

Although inferior vena cava filters (IVCFs) reduced the incidence of PE in a randomized controlled trial (RCT), patients treated with IVCFs and anticoagulation with unfractionated heparin or low-molecular- weight heparin had a greater risk of developing recurrent DVT than patients treated with anticoagulation alone (SOR: B, 1 RCT)

Cryptic diversity of Synchaeta spp. (Rotifera, Monogononta) in mountain lakes: relationships with environmental parameters

Cryptic species (i.e. distinct species that are morphologically similar) may have different ecological requirements and their merging into one species can bias the assessment of the main ecological drivers of biodiversity. We investigated the environmental parameters influencing the occurrence of Synchaeta species (S. pectinata, S. grandis, S. lakowitziana, S. tremula/oblonga - monogonont rotifers) in 17 waterbodies of the Trentino-South Tyrol region in the Eastern Alps. To improve taxonomic resolution in phylogenetic analysis, a marine Synchaeta (i.e. S. cf. cecilia) from the United Kingdom was also sampled and sequences from GenBank were downloaded. While Synchaeta species were morphologically identified based on trophi structure, cryptic species were identified based on the generalised mixed Yule coalescent (GMYC) model. We performed multivariate ordination both for morphospecies (i.e. unresolved complexes of cryptic species), a common practice in limnological studies based on morphological taxonomy, and for putative cryptic species, made possible by DNA taxonomy. We expected that resolving complexes of cryptic species could provide more information than using morphospecies. Out of the overall phylogenetic tree with 48 haplotypes from 203 individuals, the GMYC model indicated the presence of 14 GMYC entities, 11 from lakes in the Eastern Alps, 2 from Canada, and one from the U.K. Synchaeta pectinata showed five GMYC entities and S. tremula showed two; all individuals, for which the identification to S. tremula or S. oblonga was not possible, clustered in one monophyletic clade, here called S. tremula/oblonga, that showed additional evidence of three GMYC entities. Environmental-based multivariate ordination on cryptic species explained a significantly higher proportion of variance than that based on morphospecies. Occurrence of putative cryptic species was mainly related to total phosphorus. Moreover, different cryptic species within the same morphospecies showed different, and even opposite, preferences for total phosphorus. In addition, the same GMYC entity of S. tremula/oblonga found in Trentino-South Tyrol was also present in Canada and the same haplotype of S. pectinata found in Trentino-South Tyrol was also found in the U.K. This wide geographical distribution of haplotypes and cryptic species indicated the absence of dispersal barriers in Synchaet