Modelling and dynamic simulation of struvite precipitation from source-separated urine

A model of a mixed-mode nutrient recovery reactor is developed for a urine feed, incorporating complex solution thermodynamics, dynamic conservation relations and a power-law kinetic expression for crystal growth from seed crystals. Simulations at nominal operating conditions predict phosphorus recoveries greater than 99%, based on existing process kinetic parameters and operating conditions employed in previously published studies. The overall rate of nutrient recovery depends on the saturation index of the precipitating solid, the available surface area for mass transfer and the feed rate of the limiting constituent ion. Under the conditions considered, the nutrient feed rate appears to be the limiting factor for precipitation. Simulations demonstrate that diurnal feed flow variations of ±50% have a small effect on the rate of nutrient recovery. Overall, the study shows that valuable insights are gained in relation to process performance predictions, which should lead to more confident process design, operation and control

Advancing our understanding of the EU sports policy: the socio-cultural model of sports regulation and players’ agents

This paper explains the development of the socio-cultural dimension of the European Union (EU) sports policy over the course of the decade from 2005 to 2015. By adopting the theoretical lenses of the Advocacy Coalition Framework (ACF), the paper firstly offers a novel perspective on the belief systems of the members of the socio-cultural advocacy coalition that operates within the EU sports policy subsystem. A set of empirical policy core beliefs of the coalition actors reflecting their concerns regarding to sport’s integrity and economic welfare that affect its healthy development is presented and explained as the basic causes of the policy problem, i.e., threats that undermine sport’s specific characteristics. In this light, the paper then illustrates that the coalition members have perceived the issue of players’ agents, in particular problems in the activities of agents in European football, to be detrimental to the integrity of sport. As a result, the issue has been the subject of a considerable policy activity by the coalition actors with a view to establishing an alternative regulatory framework to effectively govern players’ agents. Consequently, the paper elucidates the evolving nature of the socio-cultural model of sports regulation that not only promotes the social role of sport in Europe but now also addresses the problems that affect its well-being and clear image. The paper’s principal method of investigation is based on the content analysis of official policy documents and statements of the coalition actors

Black Soldier Fly (Hermitia illucens) Larvae Meal as Alternative Protein in Broiler Production in Ghana

Feed cost has been a major challenge to the competitiveness of the poultry industry of Ghana due mainly to high cost of proteins. Insect larvae meals seem convenient alternatives however their use on commercial scale is unknown in Ghana. Three 8-week feeding trial using three isonitrogenous, isocaloric diets in a three-phase feeding strategy involving 1320 broiler DOCs was conducted. BSFLM was used as replacement for fishmeal and as partial replacement for soybean meal to determine its effect on broiler productivity, profitability and carcass measurements. The results indicated that replacing fishmeal with BSFLM significantly improved weight gain, feed conversion efficiency and production efficiency factor (PEF). No detrimental effect was observed on carcass and specific organ measurements. Using the partial budgeting approach on a 500-bird estimation an increase of one thousand, one hundred and eleven Ghana cedis (GH₵1,111.00) was obtained when the fishmeal was replaced with BSFLM. Also, an increase of four hundred and sixty-seven Ghana cedis (GH₵467.00) was estimated when soybean meal was partially replaced with BSFLM. It was concluded that BSFLM can be used to improve the productivity and profitability of broiler production

Changes in the frequency of common plant species across linear features in Wales from 1990 to 2016: implications for potential delivery of ecosystem services

In 2016, 21 1km squares recorded in Wales as part of the Countryside Survey of Great Britain were revisited. One hundred and thirty seven quadrats alongside linear features that had all been recorded in the same place in 1990, 1998 and 2007 were re-found and the plant species compositions recorded. Changes in individual species frequency were analysed and the results summarised by a number of ecosystem services and one disservice whose delivery are linked to functionally important species being present. Results indicated a continuation of a trend toward increased shading and woody cover seen between the first Countryside Survey in 1978 and the last in 2007. Most species showed no significant change in frequency suggesting that the significant directional trend seems only to have impacted a subset of the species present. A greater sample size would be required to capture impacts on a larger number of species including a wider range of Common Standards Monitoring (CSM) positive indicator species that may find refuge on the linear network in lowland Wales. Having grouped species by the ecosystem services they help deliver, we found that injurious weeds (an ecosystem disservice to food production) either declined or remained stable, a greater number of butterfly larval food plants decreased than increased and there was a net decline in potential nectar yield. Consistent with the successional trend, increasing species in these service-providing groups tended to be tall or shade-tolerant herbs and tree species. Decreasing species tended to be short, shade-intolerant forbs

(gamma,np) reactions in ¹²C , ⁶Li and ^3,4He

The emission of neutron-proton pairs is the most probable outcome of photon absorbtion in the energy region above the giant resonance at least up to the pion threshold, but little detailed information on the process has been obtained due to experimental difficulties. Two nucleon emission following photon absorbtion by a correlated pair is favoured compared to direct knockout of a single nucleon, which is suppressed by the large momentum mismatch between the ingoing photon and a single outgoing fast nucleon. Studies of the (gamma,np) process seek firstly to obtain a quantitative understanding of the photon interaction mechanism, and through this to open the door to investigations of nucleon correlations in nuclei [1], information about which is long sought but not readily obtainable

Complementary methods to investigate the development of clogging within a horizontal sub-surface flow tertiary treatment wetland

A combination of experimental methods was applied at a clogged, horizontal subsurface flow (HSSF) municipal wastewater tertiary treatment wetland (TW) in the UK, to quantify the extent of surface and subsurface clogging which had resulted in undesirable surface flow. The three dimensional hydraulic conductivity profile was determined, using a purpose made device which recreates the constant head permeameter test in-situ. The hydrodynamic pathways were investigated by performing dye tracing tests with Rhodamine WT and a novel multi-channel, data-logging, flow through Fluorimeter which allows synchronous measurements to be taken from a matrix of sampling points. Hydraulic conductivity varied in all planes, with the lowest measurement of 0.1 md1 corresponding to the surface layer at the inlet, and the maximum measurement of 1550 md1 located at a 0.4m depth at the outlet. According to dye tracing results, the region where the overland flow ceased received five times the average flow, which then vertically short-circuited below the rhizosphere. The tracer break-through curve obtained from the outlet showed that this preferential flow-path accounted for approximately 80% of the flow overall and arrived 8 h before a distinctly separate secondary flow-path. The overall volumetric efficiencyof the clogged system was 71% and the hydrology was simulated using a dual-path, dead-zone storage model. It is concluded that uneven inlet distribution, continuous surface loading and high rhizosphere resistance is responsible for the clog formation observed in this system. The average inlet hydraulic conductivity was 2 md1, suggesting that current European design guidelines, which predict that the system will reach an equilibrium hydraulic conductivity of 86 md1, do not adequately describe the hydrology of mature systems

A large mid-Holocene estuary was not present in the lower River Murray, Australia

Recent research has suggested that during the mid-Holocene (c. 8500 to 5000 cal yr BP) a large estuary occupied the lower River Murray and its terminal lakes (Lakes Alexandrina and Albert: herein the Lower Lakes) in South Australia. This research has questioned both reconstructions of past River Murray discharge and contemporary environmental water provisions aimed at maintaining the freshwater state of the Lower Lakes. We show that (1) a large mid-Holocene estuary extending into the lower River Murray was not physically possible, and (2) that the River Murray and Lower Lakes were predominantly fresh during the mid-Holocene. Sea level was well below present at the time of purported initiation of estuarine sedimentation and, therefore, could not have allowed formation of an estuary. Holocene human occupation of the lower River Murray valley, that was reliant on freshwater resources, negates the existence of a large estuary in the valley. A variety of freshwater indicators in sediments from in, and around, the Lower Lakes negate the notion of significant marine incursion. Hence, current management of the Lower Lakes as freshwater ecosystems is consistent with their Holocene history.J. Tibby, B. Bourman, C. Wilson, L. M. Mosley, A. P. Belperio, D. D. Ryan ... et al

Hypogene Calcitization: Evaporite Diagenesis in the Western Delaware Basin

Evaporite calcitization within the Castile Formation of the Delaware Basin is more widespread and diverse than originally recognized. Coupled field and GIS studies have identified more than 1000 individual occurrences of calcitization within the Castile Formation outcrop area, which includes both calcitized masses (limestone buttes) and laterally extensive calcitized horizons (limestone sheets). Both limestone buttes and sheets commonly contain a central brecciated zone that we attribute to hypogene dissolution. Lithologic fabric of calcitized zones ranges from little alteration of original varved laminae to fabrics showing extensive laminae distortion as well as extensive vuggy and open cavernous porosity. Calcitization is most abundant in the western portion of the Castile outcrop region where surface denudation has been greatest. Calcitization often forms linear trends, indicating fluid migration along fractures, but also occurs as dense clusters indicating focused, ascending, hydrocarbon-rich fluids. Native sulfur, secondary tabular gypsum (i.e. selenite) and hypogene caves are commonly associated with clusters of calcitization. This assemblage suggests that calcium sulfate diagenesis within the Castile Formation is dominated by hypogene speleogemesis