Search results for "WASTE"
showing 10 items of 2580 documents
Electrochemical oxidation of organics in water: Role of operative parameters in the absence and in the presence of NaCl
2008
The electrochemical oxidation of organics in water was investigated theoretically and experimentally to determine the role of several operative parameters on the performances of the process in the presence and in the absence of sodium chloride. Theoretical considerations were used to design the experimental investigation and were confirmed by the results of the electrochemical oxidation of oxalic acid (OA) at boron doped diamond (BDD) or IrO(2)-Ta(2)O(5) (DSA-O(2)) anodes in a continuous batch recirculation reaction system equipped with a parallel plate undivided electrochemical cell. Polarization curves and chronoamperometric measurements indicated that, in the presence of chlorides, the a…
Effect of intracellular P content on phosphate removal in Scenedesmus sp. Experimental study and kinetic expression
2014
The present work determines the effect of phosphorus content on phosphate uptake rate in a mixed culture of Chlorophyceae in which the genus Scenedesmus dominates. Phosphate uptake rate was determined in eighteen laboratory batch experiments, with samples taken from a progressively more P-starved culture in which a minimum P content of 0.11% (w/w) was achieved. The results obtained showed that the higher the internal biomass P content, the lower the phosphate removal rate. The highest specific phosphate removal rate was 6.5 mgPO4 P gTSS -1 h -1 . Microalgae with a P content around 1% (w/w) attained 10% of this highest removal rate, whereas those with a P content of 0.6% (w/w) presented 50% …
The contingent equilibrium during imbalanced volcano tourism demand through fee estimation: An empirical analysis of tourism in Mt. Etna
2022
Volcanic sites can be considered strategic areas for conservation and protection policies, but such policies may involve considerable costs However, not only are volcanic sites often integral to the tourism industry and, hence, of potential significant benefit to local economies in general; entrance fee income from tourists can also contribute to management and conservation costs in particular. Nevertheless, seasonal variations in tourism demand, resulting in over-and under-tourism situations, may impact on both the level of income generated as well as on the sustainability of sites Therefore, based on a case study of Mt Etna in Italy, this study considers establishing appropriate entry fee…
What is socio-ecological research delivering? A literature survey across 25 international LTSER platforms
2018
[Departement_IRSTEA]Eaux [TR1_IRSTEA]QUASARE [ADD1_IRSTEA]Systèmes aquatiques soumis à des pressions multiples; International audience; With an overarching goal of addressing global and regional sustainability challenges, Long Term Socio-Ecological Research Platforms (LTSER) aim to conduct place-based research, to collect and synthesize both environmental and socio-economic data, and to involve a broader stakeholder pool to set the research agenda. To date there have been few studies examining the output from LTSER platforms. In this study we enquire if the socio-ecological research from 25 self-selected LTSER platforms of the International Long-Term Ecological Research (ILTER) network has …
Assessment of clogging in constructed wetlands by saturated hydraulic conductivity measurements
2019
Abstract This study aims at defining a methodology to evaluate Ks reductions of gravel material constituting constructed wetland (CW) bed matrices. Several schemes and equations for the Lefranc's test were compared by using different gravel sizes and at multiple spatial scales. The falling-head test method was implemented by using two steel permeameters: one impervious (IMP) and one pervious (P) on one side. At laboratory scale, mean K values for a small size gravel (8–15 × 10−2 m) measured by the IMP and the P permeameters were equal to 19,466 m/d and 30,662 m/d, respectively. Mean Ks values for a big size gravel (10–25 × 10−2 m) measured by the IMP and the P permeameters were equal to 12,…
Modeling light and temperature influence on ammonium removal by Scenedesmus sp. under outdoor conditions.
2016
[EN] The ammonium removal rate of the microalga Scenedesmus sp. was studied under outdoor conditions. Microalgae were grown in a 500 L flat-plate photobioreactor and fed with the effluent of a submerged anaerobic membrane bioreactor. Temperature ranged between 9.5 WC and 32.5 WC and maximum light intensity was 1,860 μmol·m2·s1. A maximum specific ammonium removal rate of 3.71 mg NH4 þ-N·g TSS1·h1 was measured (at 22.6 WC and with a light intensity of 1,734 μmol·m2·s1). A mathematical model considering the influence of ammonium concentration, light and temperature was validated. The model successfully reproduced the observed values of ammonium removal rate obtained and it is thus p…
Photo-induced fluorescence of magnesium derivatives of tetracycline antibiotics in wastewater samples
2009
Abstract An analytical strategy, for the determination of tetracyclines (TCs), based on a HPLC system coupled with a photo-reactor followed by post-column derivatization was developed. Higher fluorescence emission after coupling the resulting photo-fragments with magnesium ions was observed for the determination of minocycline (MC), epitetracycline (ETC), tetracycline (TC) and doxycycline (DC). The manifold included a HPLC system with a photo-reactor (PTFE tubing helically coiled around a low-pressure mercury lamp), a mixing T-piece and a fluorescence detector. The derivatization reagent was delivered at 0.5 mL min −1 by a pump. After HPLC separation using a gradient system with a mobile ph…
Chemical composition of lipophilic extractives from grey alder (Alnus incana)
2013
The chemical composition of the lipophilic extractives in the hexane extracts from grey alder bark, knotwood, and cones has been investigated by gas chromatography and gas chromatography-mass spectrometry. The efficiency of two extraction methods was compared. The highest amount of lipophilic extractives (about 9% of o.d. material) was observed in grey alder cone, while the lowest (about 3%) was found in knotwood. The three different morphological parts of alder showed significant differences not only in the content but also in composition of extractives, namely fatty acids, triglycerides, and triterpenes. The main identified compounds were triterpenoids (lupen-3-one, lupeol, betulone, betu…
Melatonin alleviates Ochratoxin A-induced liver inflammation involved intestinal microbiota homeostasis and microbiota-independent manner.
2021
Melatonin (MEL) shows an anti-inflammatory effect and regulates intestinal microbiota communities in animals and humans; Ochratoxin A (OTA) induces liver inflammation through intestinal microbiota. However, it remains to know whether MEL alleviates the liver inflammation induced by OTA. In this study, MEL reversed various adverse effects induced by OTA. MEL recovered the swarming and motility of intestinal microbiota, decreased the accumulation of lipopolysaccharide (LPS), enhanced the tight junction proteins of jejunum and cecum segments; ultimately alleviated OTA-induced liver inflammation in ducks. However, it is worth noting that MEL still had positive effects on the OTA-exposed ducks a…
Integrated satellite data fusion and mining for monitoring lake water quality status of the Albufera de Valencia in Spain
2015
Abstract Lake eutrophication is a critical issue in the interplay of water supply, environmental management, and ecosystem conservation. Integrated sensing, monitoring, and modeling for a holistic lake water quality assessment with respect to multiple constituents is in acute need. The aim of this paper is to develop an integrated algorithm for data fusion and mining of satellite remote sensing images to generate daily estimates of some water quality parameters of interest, such as chlorophyll a concentrations and water transparency, to be applied for the assessment of the hypertrophic Albufera de Valencia. The Albufera de Valencia is the largest freshwater lake in Spain, which can often pr…