The recently developed Local Climate Zones (LCZ) classification system was initially not designed for mapping, but to classify temperature observation sites. Nevertheless, as a need arose to ...characterize areas based on their distinct thermal climate, utilizing LCZ classes for mapping was a logical step. The objectives of this study were (1) to develop GIS methods for the calculation of different surface parameters required for LCZ classification; (2) to identify and delineate the LCZ types within the study area using the calculated parameters; and (3) to select re presentative station sites for an urban monitoring network utilizing both the mapped LCZs and the modelled mean annual temperature surplus pattern in Szeged, Hungary. The study used remotely sensed data, maps and GIS databases of the city and its surroundings. The basic area of calculation was the lot area polygon, consisting of a building and its close vicinity. Adjoining polygons classified with identical or similar parameters were merged to obtain LCZs of appropriate size. As a result, 6 built LCZ types were distinguished in the studied urban area. The temperature pattern in the city was provided by an empirical model. The siting of stations took both the LCZ map and the modelled temperature pattern into account. The lampposts onto which the stations were to be mounted were determined by field surveys. The bias between the temperature pattern interpolated from the 24 stations and the initially estimated distribution by the model was found to be small. LCZ mapping is the first step in the development of urban climate maps (UCMs) that carry information on the spatial distribution and magnitude of the heat stress (thermal loads) and on the ventilation ability (dynamical potential) of different urban areas.
We consider a well-known diffuse interface model for the study of the evolution of an incompressible binary fluid flow in a two or three-dimensional bounded domain. This model consists of a system of ...two evolution equations, namely, the incompressible Navier-Stokes equations for the average fluid velocity
u
coupled with a convective Cahn–Hilliard equation for an order parameter
ϕ
. The novelty is that the system is endowed with boundary conditions which account for a moving contact line slip velocity. The existence of a suitable global energy solution is proven and the convergence of any such solution to a single equilibrium is also established.
We consider a system of nonlinear diffusion equations modelling (isothermal) phase segregation of an ideal mixture of
N
≥
2
components occupying a bounded region
Ω
⊂
R
d
,
d
≤
3
. Our system is ...subject to a constant mobility matrix of coefficients, a free energy functional given in terms of
singular entropy
generated potentials and
localized
capillarity effects. We prove well-posedness and regularity results which generalize the ones obtained by Elliott and Luckhaus (IMA Preprint Ser 887, 1991). In particular, if
d
≤
2
, we derive the uniform strict separation of solutions from the singular points of the (entropy) nonlinearity. Then, even if
d
=
3
, we prove the existence of a global (regular) attractor as well as we establish the convergence of solutions to single equilibria. If
d
=
3
, this convergence requires the validity of the asymptotic strict separation property. This work constitutes the first part of an extended three-part study involving the phase behavior of multi-component systems, with a second part addressing the presence of nonlocal capillarity effects, and a final part concerning the numerical study of such systems along with some relevant application.
•Plume delineation is assessed based on Br/Cl, δ11B and pharmaceutical compounds.•Gadolinium is a robust tracer of WWTP impact in groundwater.•Better plume delineation is assessed by integrating ...multiple tracers.•Pharmaceutical compounds' occurrence is studied along the plume.
Infiltration of effluents from wastewater treatment plants (WWTP) into groundwater can be a source of Contaminants of Emerging Concern (CECs), such as pharmaceutical compounds, that are not fully removed during the treatment processes. A multi-tracer approach, based on hydrogeochemical, isotopic, and organic tracers, is applied in the Vistrenque Aquifer (Gard, France) to assess the dispersion of such unintentional plumes and its potential implication on groundwater quality for CECs in a small catchment area. In this area, a point source of WWTP effluent causes contaminant infiltration and unintentional transfer to the aquifer. This strong impact of an urban effluent was revealed from the Br/Cl ratio, boron concentrations and δ11B isotopic signature of the groundwater in the direct vicinity of the infiltration point. With increasing distance from that point, dilution with groundwater rapidly attenuates the urban signal from these hydrogeochemical and isotopic tracers. Nevertheless, a gadolinium anomaly, resulting from discharges of urban wastewater containing the contrast agents used for magnetic resonance imaging (MRI), highlights the presence of a wastewater plume further along the flow line, that comes with a series of organic molecules, including pharmaceutical residues. Monitoring persistent or reactive molecules along the plume provides a more detailed understanding of the transfer of CECs into groundwater bodies. This highlights the relevance of pharmaceutical compounds as co-tracers for WWTP plume delineation. The present multi-tracer approach for groundwater resource vulnerability towards CECs allows a more in-depth understanding of contaminant transfer and their fate in groundwater.
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The aim of this study was to retire the risk of maintaining the integrity of S2-glass reinforced CTD-403 (a cyanate ester resin) that is exposed to radiation and elevated temperature over the life of ...the MOLLER experiment in experimental Hall A at Jefferson Lab. In this paper, the shear strength and flexural modulus of irradiated S2-glass reinforced CTD-403 specimens were measured at 65 °C (the magnets are to operate at less than 65 °C) under two scenarios: vacuum and gaseous nitrogen. The testing method is the Short-Beam Shear (SBS) test according to ASTM D2344. The specimens were exposed to neutrons and gamma-rays up to 124 MGy. The results show that specimens have excellent resistance against radiation, only 23% degradation of apparent shear strength with 124 MGy at 65 °C under vacuum. At the highest dose areas of the coils tungsten plates are used to reduce the radiation dose to the resin system. The conclusion is that S2-glass reinforced CTD-403 is well suited for electrical insulation of MOLLER magnets.
The transfer of metal and metalloid trace elements (MTEs) from contaminated soil to grapevines is a major issue for grape consumption and for the associated health risks. Based on an isotopic ...approach, we shed light on the concept of MTE bioavailability. The bioavailable fractions are identified by using the Sr-isotope ratio as a proxy for MTEs. This allows us to differentiate three soil reservoirs: the ‘current available fraction’ in soil water, the ‘reserve available fraction’ stored in mineral phases of the soil fractions, and the ‘non-available fraction’. The reserve available fraction, representing 10 to 60% of bulk soil depending on the MTE, includes the exchangeable, carbonates, humic substance and oxides fractions. The 87Sr/86Sr isotopic signatures of grape berries and vine leaves show an additional source of MTEs, which is imported by foliar uptake and can contribute up to 10% of the MTEs in leaves. In addition, root-uptake and translocation rates show high accumulation rates of Co, Sn and Cu, and low ones for As, Sb, Zn and Cd. A daily intake between 1 and 3 kg of (dry grapes) would reach the benchmark dose level for a 0.5% (BMDL0.5). While such a daily intake of grapes is unreasonable, consumption of other local vegetables and fruit would contribute to the daily intake. Hence, a chronic arsenic exposure is of great concern for human health in mining areas. We outline the importance of geochemical tracers, such as Sr isotopes, when determining the transfer and translocation of MTEs in plants. Our method presents a high-precision evaluation of the bioavailability and bioaccumulation of MTEs, and a better understanding of these processes in plants, thus leading to a better assessment of the environmental risk on human health.
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•Sr isotopes are a suitable tracer for MTEs and As transfer in grapevine.•Three MTEs and As reservoirs were identified in the studied soil.•The highest MTEs and As concentrations were observed in leaves.•Foliar uptake contributes up to 10% of the MTEs in leaves.•The chronic As exposure is of great concern in the mining areas.
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