10 research outputs found
A public early intervention approach to first-episode psychosis: Treated incidence over 7 years in the Emilia-Romagna region
AimTo estimate the treated incidence of individuals with first-episode psychosis (FEP) who contacted the Emilia-Romagna public mental healthcare system (Italy); to examine the variability of incidence and user characteristics across centres and years. MethodsWe computed the raw treated incidence in 2013-2019, based on FEP users aged 18-35, seen within or outside the regional program for FEP. We modelled FEP incidence across 10 catchment areas and 7 years using Bayesian Poisson and Negative Binomial Generalized Linear Models of varying complexity. We explored associations between user characteristics, study centre and year comparing variables and socioclinical clusters of subjects. ResultsThousand three hundred and eighteen individuals were treated for FEP (raw incidence: 25.3 / 100.000 inhabitant year, IQR: 15.3). A Negative Binomial location-scale model with area, population density and year as predictors found that incidence and its variability changed across centres (Bologna: 36.55; 95% CrI: 30.39-43.86; Imola: 3.07; 95% CrI: 1.61-4.99) but did not follow linear temporal trends or density. Centers were associated with different user age, gender, migrant status, occupation, living conditions and cluster distribution. Year was associated negatively with HoNOS score (R = -0.09, p < .001), duration of untreated psychosis (R = -0.12, p < .001) and referral type. ConclusionsThe Emilia-Romagna region presents a relatively high but variable incidence of FEP across areas, but not in time. More granular information on social, ethnic and cultural factors may increase the level of explanation and prediction of FEP incidence and characteristics, shedding light on social and healthcare factors influencing FEP
Chemical looping combustion in a bed of iron loaded geopolymers
The chemical looping combustion allows for inherent CO2 separation when burning fossil fuels in presence of a suitable oxygen
carrier. The choice of the material to be used should take into account not only chemical/physical properties but also economical,
environmental, and safety concerns, addressing for more common materials, like Fe oxides. In this research a geopolymeric
oxygen carrier, based on Fe2O3, was tested for the first time in a laboratory CLC plant operated at high temperature for the
combustion of a CO rich gas from char gasification in CO2. The CLC plant reliably performed in repeated cycles without decay
of the CO conversion during the chemical looping combustion. The maximum CO content in the flue gas was around 1% vol. and
carbon monoxide conversion achieved 97%. The calculated oxygen transport capacity was 0.66%. The plant results were
confirmed by the XRD analysis that proved the presence of reduced phases in samples after chemical looping stage and by
significant peaks obtained during H2 reduction in TPR equipmen
High temperature behaviour of ambient cured alkali-activated materials based on ladle slag
This paper investigates the thermal properties of alkali activated materials (AAMs) made from ladle slag, a
by-product from electric arc furnaces. AAMs have the potential to exhibit improved durability in high temperature
environments over conventionalmaterials such as ordinary Portland cement due to a reduced concentration
of hydrated phases in their structure. A series of sampleswith varying compositional ratioswas synthesised from
a combination of ladle slag and metakaolin or ladle slag and fly ash. Ambient cured AAMs ofmoderate compressive
strengths (between 11 and 46 MPa) were achieved. Samples were exposed to temperatures up to 1000 °C
and analysed for residual strength, thermal expansion, phase and microstructural changes. The ladle slag and fly
ash based AAMs exhibited superior strength gains and better thermal stability than the ladle slag and metakaolin
based AAMs believed to be due to unstable CâAâSâH phases formed in the latter group of samples
CO2 adsorption at intermediate and low temperature by geopolymer-hydrotalcite composites
Geopolymer-hydrotalcites composites have been prepared and compared to explore their use in the field of CO2
adsorption for a wide range of working temperatures and relative applications. Two commercial hydrotalcites,
with different Mg:Al ratio, were tested as fillers for a geopolymer matrix up to the maximum of 37 wt%. A high
compressive strength (25\u201327 MPa) was retained in composites at 500 C, which is the temperature of hydrotalcites
transformation into amorphous mixed solid oxides able to adsorb CO2. Composites were characterized in
term of working capacity by testing the CO2 adsorption at low (35 C) and intermediate (200 C) temperature,
with cycles of adsorption/desorption and regeneration at 500 C. At 35 C, CO2 physisorption capacity was between
0.079 and 0.154 mmol g1, while at 200 C, the total CO2 capacity value was between 0.114 and 0.141
mmol g1.
1. Introduction
In recent years, the sequestration of CO2 downstream of industrial
processes has been the subject of in-depth investigations [1]. The
adsorption of CO2 is also of great importance for the direct use of biogas
[2] where the methane must be purified before being introduced into the
distribution network, as a renewable alternative to natural gas.
The choice of the separation technology depends on the impact of the
industrial process, on the efficiency of the adsorbent and on economic
factors. Physical adsorption is a less-energy-intensive separation technology
resulting an economic alternative in comparison to others [3]. In
most cases, the solid adsorbents are in the form of monoliths or granules
to facilitate handling and storage [4]. The adsorbent material must have
high resistance to abrasion and withstand rapid changes in temperature
and/or pressure, as the methods of regenerating the adsorbent with the
release of CO2 require fluctuations in pressure and/or temperature [5,6].
The key parameter for assessing the validity of an adsorbent is the specific
adsorption capacity of CO2 (moles of CO2 per kg of material), which
depends o
Geopolymer-hydrotalcite compositws for CO2 capture
Supporting or shaping a porous powder is important for industrial applications as optimized structure with high mass transfer, low pressure drop and high mechanical and chemical stability can be obtained A new class of geopolymer-hydrotalcite composites with suitable mechanical and thermal properties were conceived as shaped materials for CO2 adsorption applications at intermediate temperature (200 e400 C). Composite monoliths were produced mixing different commercial hydrotalcite-type (HyT)
powders with a metakaolin-based geopolymer matrix with a molar ratio SiO2:Al2O3 \ubc 4.0. The compressive strength at room temperature and 500 C ranged between 10 and 35 MPa, mainly depending on HyT powder morphology and composite total porosity. The composites were characterized and tested in term of CO2 uptake. After calcination to convert HyT into an amorphous Mg:Al mixed solid oxide able to absorb CO2, the composites were tested in the CO2 adsorption at 200 C, with cycles of
adsorption/desorption performed with intermediate regeneration at 500 C. CO2 adsorption capacity was in the range 0.375e0.461 mmol g1 for HyT and between 0.109 and 0.145 mmol g1 for composites, being 0.052 mmol g1 the value for the geopolymer matrix. A partial deactivation of the HyT phases was also detected
Mechanical strength and cationic dye adsorption ability of metakaolin-based geopolymer spheres
Metakaolin-based geopolymer spheres shaped by three different dripping techniques were investigated in terms of compressive strength and dye adsorption ability. Spheres were produced by injection and solidification in polyethylene glycol (PEG) or liquid nitrogen (ice-templating) and ionotropic gelation (alginate in calcium chloride). Mechanical tests by ISO 18591 evidenced that compressive strength was strictly linked to porosity and composition of the spheres, being 12.9 MPa with 29% of porosity for spheres produced in PEG, 2.1 MPa with a porosity of 64% for spheres shaped in liquid nitrogen and up to 19.6 MPa with a porosity of 59% for hybrid spheres with a skeleton of Ca-alginate. The influence of contact time and initial concentration on a cationic dye (methylene blue) adsorption was studied. Removal efficiency was related to morphology, porosity and specific surface area: after 24 h the percentage of adsorption was 94\u201398% for spheres shaped in liquid nitrogen while below 75% for hybrid spheres and spheres produced in PEG. By adding TiO2 P25 as photocatalytic phase to the hybrid spheres, an increase of removal efficiency of 33% was observed after 90 min under UV irradiation