Search results for "wage"

Notes on Using the Hidden Asset or the Contribution Asset to Compile the Actuarial Balance for Pay-as-You-Go Pension Systems

2010

The aim of this paper is twofold: to determine the connection between the “contribution asset” and the “hidden asset” and to discover whether using either of them to compile the actuarial balance in Swedish-type pay-as-you-go pension systems will provide a reliable solvency indicator. We develop an overlapping generations model and apply it to the defined benefit pay-as-you-go system, although it would be just as valid for NDC systems. On the theoretical side the main conclusion is that, despite their very different natures, in a simplified scenario the contribution asset and the hidden asset could coincide if r - the real rate of interest - is equal to the growth in the wage bill. On the a…

Immobilised Humic Substances as Low-Cost Sorbents for Emerging Contaminants

2021

Environmental pollution with contaminants of emerging concern (CECs) is a worldwide problem that is receiving increasing attention. Although these substances have been released in the aquatic environment for a long time, wastewater treatment plants are still incapable of removing emerging contaminants completely. Consequently, trace metals, metalloids and pharmaceuticals, as well as surfactant leftovers, are often found in environmental samples. Environmentally friendly and cost-effective sorbents such as humic substances can be used for purification if their sorption properties are increased by immobilization. To our knowledge, immobilized humic substances have not been widely studied as s…

Wages in the industrial research sector : the case in engineers in Spain

1997

Estimation of alcohol consumption during >Fallas> festivity in the wastewater of Valencia city (Spain) using ethyl sulfate as a biomarker

2016

Alcohol consumption has been increasing in the last years and it has become a sociological problem due its derived health and safety problems. Ethyl sulfate is a secondary metabolite of the alcohol degradation that is excreted through the urine (0.010-0.016%) after alcohol ingestion and it is quite stable in water. In this study, a new methodology to determine ethyl sulfate by ion-pair liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed. Different ion-pairs and additives were tested directly in the sample extracts or in the mobile phase. The best ion-pair was set up adding 0.5M of tributylamine and 0.1% of formic acid to the sample. The limit of quantification was 0.3μgL…

Purification of recovered phosphoric acid by extracting aluminium with di-2-ethylhexyl phosphoric acid

2021

AbstractThe extraction of aluminium from dilute phosphoric acid with di-2-ethylhexyl phosphoric acid (DEHPA) was optimized using response surface methodology. The optimization was based on the experimental three-level central composite face-centred design (CCF) and was conducted on real-life samples. The three variables included were pH, extractant concentration and aqueous to organic phase ratio (AO). Under the optimized conditions (pH 2.5, 0.6 M DEHPA and AO ratio 1:2), extraction efficiency of 99% for aluminium in four extraction stages is achieved. The purified phosphoric acid solution can then be utilized by the fertilizing industry. Stripping tests for organic phase loaded with alumin…

Latvia: Both Sides of the Economic Recovery Success Story

2016

Latvian social policy is close to the neoliberal model of the welfare state based on macroeconomic indicators of low welfare state spending, high income inequality, low minimum wage and low degree of decommodification. Latvia was among the first countries to be stung by the crisis in 2008. Key words became: austerity, fiscal consolidation and structural adjustment measures. A minimum social safety network was introduced to improve targeted social support. Funding from the European Social Fund was instrumental in mitigating unemployment, facilitating a large temporary works programme. Latvia joined the Euro zone in 2014 and is quite successfully returning loans. Such is one side of the succe…

Implementation of a global P-recovery system in urban wastewater treatment plants

2019

[EN] Current wastewater treatment plants (WWTPs) paradigm is moving towards the so-called water resource recovery facilities in which sewage is considered a source of valuable resources. In particular, urban WWTPs are crucial systems to enhance phosphorus (P) recycling. This paper evaluates the implementation of a P-recovery system in Calahorra WWTP combining the operation of a new sludge line configuration coupled to a struvite crystallisation reactor at demonstration-scale. This new configuration consisted in the elutriation in the gravity thickener of the mixed sludge contained in the mixing chamber in order to reduce the phosphate load to the anaerobic digestion. The results indicated t…

Effects of sewage sludge addition to Norway spruce seedlings on nitrogen availability and soil fauna in clear-cut areas

2012

Anaerobically digested and composted sewage sludge (CSS) has been suggested to be a slow-release fertilizer in forestry and an alternative to quick-release inorganic fertilizers. The effects of CSS with or without added carbohydrate on inorganic nitrogen availability and on soil animals were tested in two Norway spruce plantations. Half of the seedlings were individually fertilized with CSS, and the rest were left as controls. Solid sucrose was added to half of the fertilized and untreated seedlings. Soil samples were taken in the autumn in the first and the second year after the treatments. CSS increased soil NH4-N (2100%), the proportion of soil NO3-N, and the N concentration of spruce ne…

Activated Sludge Systems as Diferential Equations: A Fresh View on the Classical Models for Wastewater Treatment Plants

2014

Abstract Present in the theory and practice of wastewater treatment for over 50 years in consistent numbers, activated sludge models are widely used by plant operators. The early stage models, based on differential equations were synthetized and reinterpreted, presenting new insides that can help to a better understanding of the processes involved in the wastewater treatment. A consistent symbology is presented, for a much homogenous perspective, and the obvious similarities between several equations from the models are pointed out. The incomplete information from the models is emphasized, showing their amount of providing supplementary data for plant operators and researchers in the field,…

Comparison of laboratory-scale thermophilic biofilm and activated sludge processes integrated with a mesophilic activated sludge process

2003

A combined thermophilic-mesophilic wastewater treatment was studied using a laboratory-scale thermophilic activated sludge process (ASP) followed by mesophilic ASP or a thermophilic suspended carrier biofilm process (SCBP) followed by mesophilic ASP, both systems treating diluted molasses (dilution factor 1:500 corresponding GF/A-filtered COD (COD(filt)) of 1900+/-190 mgl(-1)). With hydraulic retention times (HRTs) of 12-18 h the thermophilic ASP and thermophilic SCBP removed 60+/-13% and 62+/-7% of COD(filt), respectively, with HRT of 8 h the removals were 48+/-1% and 69+/-4%. The sludge volume index (SVI) was notably lower in the thermophilic SCBP (measured from suspended sludge) than in …