146 research outputs found
A sustainable process for biodiesel production using Zn/Mg oxidic species as active, selective and reusable heterogeneous catalysts
This paper describes the preparation and characterization of MgO and ZnO-based catalysts, pure and mixed in different proportions, supported on γ-Al2O3. Their catalytic performance was studied in the transesterification of soybean oil and castor oil with methanol and butanol, attempting to produce biodiesel. XRD (X-ray diffraction), SEM?EDS (scanning electron microscopy?energy dispersive X-ray spectroscopy), CO2-adsorption and N2-adsorption allowed characterizing the prepared catalysts. The characterization results were in all cases consistent with mesoporous solids with high specific surface area. All the catalysts exhibited good results, especially in the transesterification of castor oil using butanol. For this reaction, the reuse was tested, maintaining high FABE (fatty acid butyl esters) yields after four cycles. This good performance can be attributed to the basic properties of the Mg species, and simultaneously, to the amphoteric properties of ZnO, which allow both triglycerides and free fatty acids to be converted into esters. Using these catalysts, it is possible to obtain second-generation biodiesel, employing castor oil, a raw material that does not compete with the food industry. In addition, butanol can be produced from renewable biomass.Fil: Navas, Marisa Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; ArgentinaFil: Ruggera, José Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; ArgentinaFil: Lick, Ileana Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; ArgentinaFil: Casella, Mónica L.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentin
Il trattamento endourologico retrogrado nella calcolosi renale
Negli ultimi 30 anni la terapia della calcolosi urinaria ha subito notevoli modificazioni in virtù dello sviluppo di tecnologie che hanno reso possibile eseguire trattamenti sempre meno invasivi. Anche le linee guida sono cambiate di conseguenza e attualmente prevedono che la litotrissia extracorporea rappresenti la prima opzione terapeutica per calcoli renali inferiori ai 20 mm come la litotrissia percutanea lo sia per calcoli di dimensioni superiori. Nel nostro studio abbiamo valutato efficacia e sicurezza della litotrissia per via retrograda come prima linea di trattamento della calcolosi renale. In 35 pazienti sottoposti a trattamento endourologico retrogrado abbiamo ottenuto una bonifica completa con il primo trattamento nel 63% dei casi e nell'80% con un ritrattamento. Complicanze maggiori, risolte senza sequele, sono comparse in 3 pazienti. Differenze significative sono emerse solo nel confronto dei risultati per calcoli inferiori e superiori a 20 mm. Nella nostra esperienza la RIRS può rappresentare la prima scelta di trattamento in alternativa alle altre opzioni sia per calcoli di piccole che di grandi dimensioni in casi selezionati, soprattutto se si tratta di calcolosi recidivante
Infectious Complications After Laser Vaporization of Urinary Stones During Retrograde Intrarenal Surgery Are Not Associated with Spreading of Bacteria into Irrigation Fluid but with Previous Use of Fluoroquinolones
The challenge of cystine and struvite stone formers: clinical, metabolic and surgical assessment
The efficacy of radiographic anatomical measurement methods in predicting success after extracorporeal shockwave lithotripsy for lower pole kidney stones
Incontinenza urinaria mista nelle donne: l\u2019inquadramento diagnostico Urologia 2005; 72 (4): 471-475.
Is there a rationale explaining the lower risk of colonic injuries during semi-supine versus prone percutaneous nephrolithotomy?
Low-risk for colonic injuries during supine versus prone percutaneous nephrolithotomy: which is the rationale?
none3noneRuggera L; Beltrami P; Zattoni FRuggera, L; Beltrami, P; Zattoni, Filibert
Low-risk for colonic injuries during supine versus prone percutaneous nephrolithotomy: Which is the rationale?
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