Il fascino inquieto dell’utopia

Marialuisa Bignami, cui questo volume è dedicato, è una tra le più illustri studiose dell’utopia letteraria in Italia. In dialogo con la sua opera critica, il volume discute origini ed esiti del concetto di utopia nel panorama letterario e sociale occidentale, in particolare anglosassone. La riflessione prende le mosse da un’elaborazione di stampo millenarista del pensiero utopico, per proseguire nell’indagine dei suoi esiti letterari tardorinascimentali, settecenteschi e anche coloniali; si approda infine alle utopie moderne, postmoderne e femministe del nostro tempo, senza tralasciare gli esiti dell’immaginario utopico nella cultura di massa. L’utopia, un po’ come il romanticismo, sembra essere una necessità della cultura occidentale, una categoria dello spirito, che può essere reinterpretata, negata, persino vilipesa, ma non abbandonata. I percorsi attraverso le mutazioni spazio-temporali dell’utopia raccolti in questo volume sono ispirati ad approcci critici diversi e sono trasversali a più ambiti di ricerca; la ricchezza del dibattito invita a proseguire l’indagine sui volti molteplici del genere utopico, anche attraverso l’esplorazione di nuove interazioni e di nuovi linguaggi

Extraction of metals from spent hydrotreating catalysts: Physico-mechanical pre-treatments and leaching stage

The present paper is focused on physico-mechanical pre-treatments of spent hydrotreating catalysts aimed at concentration of at least one of the valuable metals contained in such secondary raw material. In particular, dry Ni–Mo and Co–Mo as well as wet Ni–Mo catalysts were used. Flotation, grain size separation and attrition processes were tested. After that, a rods vibrating mill and a ball mill were used to ground the catalysts in order to understand the best mechanical pre-treatment before leaching extraction. The results showed that flotation is not able to concentrate any metals due to the presence of coke or other depressant compounds. The particle size separation produces two fractions enriched in Mo and Co when dry Co–Mo catalyst is used, whereas attrition is not suitable as metals are uniformely distributed in rings’ volume. Roasting at 550 °C and vibrating grinding are the most suitable pre-treatments able to produce fractions easily leached by NaOH and H2SO4 after grain size separation

Skeletal and extraskeletal angiomatosis with Kasabach-Merritt Syndrome. Report of a case

Background & Objective: Angiomatosis is general term employed to describe a spectrum of rare pathologic conditions characterized diffuse infiltration of bone, soft tissue and viscera by vascular channels filled with lymph or blood. We describe a case of paediatric angiomatosis with extensive skeletal and extraskeletal involvement, and consumption coagulopathy type Kasabach-Merritt syndrome (KMS). Method: A 3-year-old boy presented with a one-month history of left lower limb pain and swelling of the ipsilateral knee. At birth, multiple haemangioma of the soft tissues of the scalp were identified, and a lesion consistent with pulmonary sequestration was detected at chest CT scan. MRI studies revealed multiple lesions of the left femur, with soft tissue extension, of the left tibia and the right femur. A surgical biopsy was taken from the left femur, which was reported as non-diagnostic. One week later the mother reported bleeding from the site of the biopsy. Blood tests demonstrated anaemia, thrombocytopenia and both decreased and consumption of coagulation factors, consistent with KMS. Results: A new biopsy of the femur showed a proliferation of thin-walled, dilated blood vessels, in between the bony trabeculae, as well as in the cortical bone and in the adjacent soft tissues. The endothelial lining was devoid of atypia, and immunoreactive for CD31 and CD34, while podoplanin and GLUT1 were negative. Conclusion: Distinction of skeletal angiomatoses as discrete entities is difficult and has led to an array of confusing conditions with similar appearances at histology, with variable involvement of skeletal and extraskeletal sites

Il fascino inquieto dell'utopia

Marialuisa Bignami, cui questo volume è dedicato, è una tra le più illustri studiose dell’utopia letteraria in Italia. In dialogo con la sua opera critica, il volume discute origini ed esiti del concetto di utopia nel panorama letterario e sociale occidentale, in particolare anglosassone

Process for the treatment of alkaline spent batteries

In recent years there has been a growing interest in processes for the treatment of spent portable batteries, due to problem of environmental impact connected with the presence of significant quantities of heavy metals. As a matter of fact, batteries are considered special waste by current legislation that establishes specific rules for the collection, treatment, recycling and disposal of spent batteries and accumulators. In this work a process for the treatment of spent alkaline batteries is presented (Toro et al., 2006). The hydrometallurgic process comprises the following stages: Pre-treatment Acid-reducing leaching using carbohydrate as reducing agent Leach-liquor purification Separation and recovery of metallic Zn and MnO(2) (by electrowinning) The aim of this work is the optimization of the operating conditions for the selective recovery of Zn. Leaching tests were performed both at room temperature and at 90 degrees C. Experimental results denoted that at room temperature a quantitative zinc extraction was obtained with selectivity higher than at 90 degrees C. Leach-liquor solution after purification (iron precipitation and cementation) was used in electrowinning process for recovery of zinc which was obtained with 98-99% purity