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Persone positive, decedute e guarite durante l'emergenza Covid-19: la comunicazione istituzionale dell’incertezza dei dati durante la Fase 1 della pandemia in Italia
Full text linkIntroduzione. Il 31 gennaio 2020 sono stati confermati in Italia i primi due casi di COVID-19, malattia respiratoria acuta dovuta all’infezione virale da Sars-Cov-2 i cui sintomi più comuni sono tosse, febbre, affaticamento e difficoltà respiratorie ma che si può manifestare in forma grave sotto forma di polmonite interstiziale, e non solo. Il virus responsabile dell’epidemia, che sarebbe poi diventata una pandemia globale, era già stato identificato da oltre un mese in Cina, a Wuhan, capitale della provincia di Hubei. Da lì provenivano le prime due persone risultate positive in Italia, due turisti in vacanza a Roma, e anche la terza, un cittadino italiano rimpatriato da poco da Wuhan..
Il trattamento biologico di depurazione delle acque della cartiera di Tolmezzo: caratterizzazione delle biomasse tramite macroparametri e microparametri
No full textRassegna Tecnica del FV
The photodynamic inactivation of Staphylococcus aureus in water using visible light with a new expanded porphyrin.
No full textIn this work, the results of the application of organic expanded porphyrins in the disinfection of water
by the photodynamic inactivation (PDI) technique are presented. The photoinactivation properties of
a novel, expanded porphyrin, namely 20-(4-carboxyphenyl)-2,13-dimethyl-3,12-diethyl-(22π)
pentaphyrin (PCCox), were tested in the disinfection of water using Staphylococcus aureus as a
Gram-positive bacteria model. The data showed that PCCox was effective against S. aureus bacteria
at nanomolar concentrations. The variation with irradiation time and concentration was studied using
both a multi-LED monochromatic light (λ 1⁄4 470 nm) and an incandescent light bulb with a wide
emission spectrum. A PCCox dosage of 5 μM was sufficient to achieve a 99.997% abatement of
S. aureus within 1 h of 40 W/m2 irradiation with monochromatic light (λ 1⁄4 470 nm), whereas under
the same conditions using irradiation with white light, the abatement was 99.9997%
Water disinfection by photodynamic inactivation with cationic porphyrin
No full textIn recent years, the application of porphyrin derivatives in photodynamic inactivation (PDI) is
arousing great interest in water disinfection process studies. As an alternative to other disinfection
techniques traditionally used (chlorination, ozonolysis, irradiation with UV light), the photooxidation
process is a promising technology characterized by low cost, low environmental impact
and easy management.
In this work basic experimental tests about the application of organic expanded porphyrins in
water disinfection by photodynamic inactivation (PDI) technique are depicted. The
photoinactivation properties of a positive charged porphyrin, namely 5,10,15,20-Tetrakis (1-
methyl-4-pyridinio) porphyrin tetra (p-toluenesulfonate) (TMPyP), were tested in water
disinfection, using S.aureus and E.coli. Data showed that TMPyP treatment on 107 CFU/ml
bacterial culture was effective at nanomolar concentration and in a very short treatment time (15
minutes). By 1 hour of 50 W/m2 irradiation, a maximum of 99,99989 % abatement on S.aureus
and a maximum of 99,995 % abatement on E.coli, using respectively a dosage of 0,5 mM and 5
mM TMPyP, were obtained. TMPyP effectiveness was tested even on waste water and the
preliminary results demonstrated that, even if wild bacteria are generally more resistant to the
treatment, photo-oxidation is a promising technique to refine water disinfection processes
Experimental tests of ultrasonic pretreatment on organic fractions for anaerobic co-digestion
No full textDisinfezione mediante ozono di acque di piscine e vasche terapeutiche: indagini sperimentali di trattamento per il dimensionamento
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Bench-scale tests on ultrasound-assisted acidwashing and thermal desorption of mercury from dredging sludge and other solid matrices
No full textA series of ultrasonic assisted acid washing and thermal desorption tests were performed on sludge and other solid matrices with the aim to assay these removal technologies and to determine if the application of low frequency ultrasound was effective to enhance mercury removal. Unpolluted dredging sludge, 820 K calcinated dredging sludge, silica and alumina were characterized, polluted with a known concentration of mercury and treated both by acid washing and thermal desorption with and without low frequency ultrasound application. The acid washing was carried out by a 4% HNO3 acid solution and the thermal desorption was performed in a 370-620 K range. X-ray semi-quantitative analysis of dredging sludge before and after acid washing and granulometric curves of the matrices after the ultrasonic treatment were considered in order to evidence chemical or physical changes during these treatments. Total residual mercury measurements were carried out before and after sonication. Results showed not measurable acid washing extraction from polluted dredging sludge, a little (3%) extraction from 820 K heat-treated sludge and a significant (10-20%) extraction from alumina and silica within 120 min of treatment. The ultrasound application gave generally poor improvement of the mercury removal. On the contrary thermal desorption of mercury was somewhat effective for alumina, silica and heat-treated dredging sludge samples in which mercury removal was 30-40% at 370 K and 90-99% at 570 K. Likewise ultrasound application did not improve desorption. Instead, the thermal treatment of dredging sludge had a negligible amount of mercury desorption at 370 K but it reached 95% at 570 K. The application of ultrasound improved the thermal extraction of 25% in the 470-520 K range of temperature
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