Ecologische aspecten bij het bodemsaneringsbeleid in Amsterdam

Het beleid van de gemeente Amsterdam ten aanzien van bodembescherming is primair gericht op het voorkomen van risico's van bodemverontreiniging voor de mens en op het voorkomen van verspreiding van de verontreiniging(en). Bescherming van het ecosysteem wordt wel in de urgentiesystematiek betrokken, maar speelt een relatief ondergeschikte rol. De centrale doelstelling van dit rapport is na te gaan wat er bekend is over de effecten van bodemverontreinigende stoffen op bodemecosystemen in Amsterdam. De belangrijkste geconstateerde bodemverontreinigingen zijn lood, kwik, arseen, koper, zink, olie, benzeen en op enkele specifieke locaties ook polycyclische aromatische koolwaterstoffen (PAK's) en polychloorbiphenylen (PCB's). Vervolgens is beschreven welke effecten optreden bij de aandachtssoorten die leven in of op een bodem verontreinigd met de geselecteerde aandachtsstoffen in concentraties hoger dan de Eco Interventiewaarde. Het rapport wordt afgesloten met enige aanbevelingen voor nader onderzoek

Whistling of corrugated pipes

Abstract only

Hormoonontregelaars in water opsporen met biologische effectmetingen

Uitleg over de pricipes van verschillende in-vitro testen gebruikt voor het bepalen van de oestrogene potentie van monsters oppervlaktewater en afvalwater, en enige resultaten voor verschillende locaties in Nederlan

Four guidelines on cardiovascular complications and cardiovascular disease, prognosis and treatment in COVID-19

Cardiolog

Removal of steroid estrogens in carbonaceous and nitrifying activated sludge processes

This is the post-print version of the final paper published in Chemosphere. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2010 Elsevier B.V.A carbonaceous (heterotrophic) activated sludge process (ASP), nitrifying ASP and a nitrifying/denitrifying ASP have been studied to examine the role of process type in steroid estrogen removal. Biodegradation efficiencies for total steroid estrogens (ΣEST) of 80 and 91% were recorded for the nitrifying/denitrifying ASP and nitrifying ASP respectively. Total estrogen biodegradation (ΣEST) was only 51% at the carbonaceous ASP, however, the extent of biodegradation in the absence of nitrification clearly indicates the important role of heterotrophs in steroid estrogen removal. The low removal efficiency did not correlate with biomass activity for which the ASPcarbonaceous recorded 80 μg kg−1 biomass d−1 compared to 61 and 15 μg kg−1 biomass d−1 at the ASPnitrifying and ASPnitrifying/denitrifying respectively. This finding was explained by a moderate correlation (r2 = 0.55) between total estrogen loading (ΣEST mg m−3 d−1) and biomass activity (μg ΣEST degraded kg−1 d−1) and has established the impact of loading on steroid estrogen removal at full-scale. At higher solids retention time (SRT), steroid estrogen biodegradation of >80% was observed, as has previously been reported. It is postulated that hydraulic retention time (HRT) is as important as SRT as this governs both reaction time and loading. This observation is based on the high specific estrogen activity determined at the ASPcarbonaceous plant, the significance of estrogen loading and the positive linear correlation between SRT and HRT.Public Utilities Board of Singapore, Anglian Water Ltd., Severn Trent Water Ltd., Thames Water Utilities Ltd., United Utilities Plc., and Yorkshire Water Services Ltd

Determination of steroid estrogens in wastewater by high performance liquid chromatography-tandem mass spectrometry

This paper discusses the requirement for, and presents an analytical procedure for, the determination of four unconjugated steroid hormones and a conjugated steroid (estrone-3-sulfate) in wastewaters. The method quantifies the steroids by LC/MS/MS following solid phase extraction and a two stage clean-up procedure. Samples were extracted using C18 cartridges and eluates were then purified by gel permeation chromatography, followed by a further clean-up step on an aminopropyl cartridge. The limits of detection achieved were 0.2 ng l-1 for estriol, 17β-estradiol and 17α-ethinylestradiol, and 0.1 ng l-1 for estrone and the conjugate. The robustness of the method was demonstrated by achieving recoveries of >83% for all steroids in settled sewage and final effluent samples with relative standard deviations of 0.5 - 12%. The method was used to analyse a range of samples from a wastewater treatment works in south east England which demonstrated a >80% removal for estrone, estradiol and estriol with little impact on concentrations of ethinylestradiol or the conjugate

MULTIPHASE FLUID STRUCTURE INTERACTION IN BENDS AND T-JOINTS

ABSTRACT Air-water experiments were carried out in a horizontal 1" pipe system to measure the magnitude of the forces induced by the multiphase flow. Forces and accelerations were measured on a number of bends and T-joint configurations for a wide range of operating conditions. Five different configurations were measured: a baseline case consisting of straight pipe only, a sharp edged bend, a large radius bend, a symmetric T-joint and a T-joint with one of the arms closed off. The gas flow was varied from a superficial velocity of 0.1 to 30 m/s and the liquid flow was varied from 0.05 to 2 m/s. This operating range ensures that the experiment encompasses all possible flow regimes. In general, the slug velocity and frequency presented a reasonable agreement with classical models. However, for high mixture velocity the measured frequency deviated from literature models. The magnitude of the measured forces was found to vary over a wide range depending on the flow regime. For slug flow conditions very high force levels were measured, up to 4 orders of magnitude higher than in single phase flow for comparable velocities. The annular flow regime resulted in the (relative) lowest forces, although the absolute amplitude is of the same order as in the case of slug flow. These results from a one inch pipe were compared to data obtained previously from similar experiments on a 6mm setup, to evaluate the scaling effects. The results for the one inch rig experiments agreed with the model proposed by Riverin, with the same scaling factor. A modification of this scaling factor is needed for the model to predict the forces measured on the 6mm rig. The validity of the theories developed based on the 6mm experiments were tested for validity at larger scales. In case of slug flow, the measured results can be described assuming a simple slug unit model. In annular and stratified flow a different model is required, since no slug unit is present. Instead, excitation force can be estimated using mixture properties. This mixture approach also describes the forces for the slug regime relatively well. Only the single phase flow is not described properly with this mixture model, as would be expected

Flow induced pulsation caused by corrugated tubes

ABSTRACT Corrugated tubes can produce a tonal noise when used for gas transport, for instance in the case of flexible risers. The whistling sound is generated by shear layer instability due to the boundary layer separation at each corrugation. This whistling is examined by investigating the frequency, amplitude and onset of the pulsations generated by 2" artificially corrugated tubes and cable feeds. Special attention is given to the influence of the geometry of the corrugations and to the influence of the boundary conditions of the tubes. Two distinct modes are measured. One high mode with a typical Strouhal number Sr=0.35 and one with a Strouhal number of Sr=

Impact of cardiovascular disease and cardiovascular risk factors in hospitalised COVID-19 patients

Background Hospitalised COVID-19 patients with underlying cardiovascular disease (CVD) and cardiovascular risk factors appear to be at risk of poor outcome. It is unknown if these patients should be considered a vulnerable group in healthcare delivery and healthcare recommendations during the COVID-19 pandemic. Methods A systematic literature search was performed to answer the following question: In which hospitalised patients with proven COVID-19 and with underlying CVD and cardiovascular risk factors should doctors be alert to a poor outcome? Relevant outcome measures were mortality and intensive care unit admission. Medline and Embase databases were searched using relevant search terms until 9 June 2020. After systematic analysis, 8 studies were included. Results Based on the literature search, there was insufficient evidence that CVD and cardiovascular risk factors are significant predictors of mortality and poor outcome in hospitalised patients with COVID-19. Due to differences in methodology, the level of evidence of all studies was graded 'very low' according to the Grading Recommendations Assessment, Development and Evaluation methodology. It is expected that in the near future, two multinational and multicentre European registries (CAPACITY-COVID and LEOSS) will offer more insight into outcome in COVID-19 patients. Conclusion This literature review demonstrated there was insufficient evidence to identify CVD and cardiovascular risk factors as important predictors of poor outcome in hospitalised COVID-19 patients. However, patients with CVD and cardiovascular risk factors remain vulnerable to infectious disease outbreaks. As such, governmental and public health COVID-19 recommendations for vulnerable groups apply to these patients.Cardiolog