Search results for "chemical engineering"
showing 10 items of 5892 documents
Evaluation of hydroxyapatite distribution in a Poly-L-Lactic Acid (PLLA) scaffolds via Micro Computed Tomography (µCT)
2018
Bone Tissue Engineering offers promising clinical alternative substitutes for bone defects, focusing on the use of polymer/ceramic composites. Hydroxyapatite (HA), a bioactive ceramic, has been implemented in bone substitution and regeneration due to its biocompatibility, osteoconductivity and close resemblance to the mineralized phase of human bone. Several techniques have been adopted to characterize composite scaffolds in terms of morphology, pore size and interconnection, filler content and distribution, but most of them are destructives. In this work, composite Poly-L-Lactic Acid (PLLA)-HA scaffolds (17.6 mm diameter and35.7 mm height) were prepared via Thermally Induced Phase Separati…
Biotechnical characteristics of root systems in erect and prostrate habit rosmarinus officinalis L. accessions grown in a mediterranean climate
2017
Rosmarinus officinalis L. is a shrub species typically found in the Mediterranean Basin area. Studies carried out in Sicily on the biodiversity of the genus Rosmarinus found only one species (Rosmarinus officinalis L.) with varying morphology (erect habit and prostrate habit). The species does not require high input, managing to thrive even in marginal areas, and is a medicinal and aromatic species of great agronomic and economic interest, being one of the top 20 species most-used in Italy and with highest wholesale revenues. Studies carried out on the species in Italy are recent, as is the whole medicinal and aromatic plants sector, and have mostly regarded agrotechniques. This study shows…
Safety optimized shift-scheduling system based on wireless vibration monitoring for mechanical harvesting operations
2017
Traditional approaches to vibration risk assessment are often carried out manually on the basis of reference data, whereas an automated approach, can yield more valuable information that can be beneficial for improving the health and safety conditions of the workers. In particular, the exposure to prolonged vibration is a potential cause of pathologies such as the hand-arm vibration syndrome (HAVS), therefore national and international regulations establish recommended limits to the workers’ exposure to vibration within an allowable daily limit. However, evaluating the maximum allowable operating time is not straightforward, therefore reference vibration values are provided by the manufactu…
Production of a a-L-Rhamnosidase from Aspergillus Terreus Using Citrus Solid Waste as Inducer for Application in Juice Industry
2012
Naringinase is an enzyme complex consisting of a a-L-rhamnopyranosidase (Rha, EC. 3.2.1.40) and ß-D-glucopyranosidase (ßG, EC. 3.2.1.21). a-L-rhamnopyranosidase is an enzyme of considerable importance in food technology for increasing the aroma of fruit juices and alcoholic beverages. It is particularly used for debittering of citrus-juice by the hydrolysis of naringin and hesperidin, however this activity is low in commercial enzyme preparations. The aim of this work is the production of Rha from Aspergillus terreus fermentation using citrus solid waste (CSW), called “pastazzo”, as specific inducer. CSW is rich in fermentable materials such as sugars, in particular rhamnose, in pectins, an…
Potential production of biogas from prinkly pear (opuntia ficus-indica L.) in sicilian uncultivated areas
2017
The aim of this work is to evaluate the potential production of biogas and, indirectly, biomethane or electric and thermal energy, from prinkly pear (Opuntia ficus-indica L.), to be grown in a part of Sicilian uncultivated areas and co-digested together with the available livestock manure and slurry. In order to increase the Renewable Energy Sources (RES) and reduce the dependency from fossil ones, the conversion of biomass into biogas through Anaerobic Digestion (AD) process is paramount for producing biomethane, to be used as fuel for means of transport and agricultural machines or heating, or electric and thermal energy through Combined Heat and Power (CHP) plants. Moreover, the digestat…
Height of water pouring effects on infiltration runs carried out in an initially wet sandy-loam soil
2017
Ring infiltration methods are widely used for field soil hydraulic characterization. Establishing factors affecting these methods is necessary to interpret the collected data. The height from which water is poured on the soil surface is known to influence infiltration in a sandy-loam soil, since low (L, height of water pouring 0.03 m) runs yielded higher infiltration rates than high (H, 1.5 m) runs in previous investigations. The impact of water pouring height on infiltration rates seems to vary with the antecedent soil water content, θi. In this investigation, height effects on infiltration were tested for an initially very wet sandy-loam soil. Two-stage infiltration runs differing by the…
Electrodeposition and characterization of Mo oxide nanostructures
2015
Template electrodeposition has been used to grow uniform arrays of molybdenum oxide nanostructures in polycarbonate membrane. Several parameters have been investigated, like electrodeposition, time and solution pH. These parameters do not influence the nature of the deposit that always consists of mixed valence molybdenum oxides, whereas the nanostructure morphology changes with pH. In particular, at low pH (2.7), nanotubes are formed, whilst arrays of nanowires are obtained above pH 5.5. This change of morphology is likely due to H2 bubbles evolution during the electrochemical deposition, particularly occurring at low pH. It was found that fast removal of H2 bubbles through vigorous stirri…
Noise risk assessment in a modern olive oil mill
2017
High levels of noise usually occur in olive oil mills because of the machines used to extract olive oil with a continuous plant. In Italy Law Decree 81/2008 defined the requirements for assessing and managing noise risk, identifying a number of procedures to be adopted at different noise levels to limit workers exposure. This study aims at evaluating the equivalent and peak noise levels inside a modern oil mill plant area in Sicily, south Italy. Twenty measurement points were identified inside the oil mill plant area where the machines for olive oil extraction were located (about 200 m2). The instrument used for the measurements was a precision integrating portable sound level meter, class …
From microbial proteomics to synthetic biology: Amycolatopsis balhimycina case
2012
Actinomycetes, filamentous Gram-positive bacteria, are usually exploited as bio-farms naturally producing a wide range of small biologically active metabolites, such as antibiotics, extensively used in medicine, food-industry, chemistry and bio-remediation strategies. The development of high throughput technologies, like proteomics, allows functional genomic studies aimed at shedding light on molecular mechanisms controlling the production of useful compounds and macromolecules. Differential proteomic analyses, performed by using Two Dimensional PolyAcrylamide Gel Electrophoresis (2D-PAGE) coupled to mass spectrometry (MS) procedures, revealed novel links between balhimycin production (a va…
Drying kinetics and physico-chemical quality of mango slices
2019
Mango (Mangifera indica L.) is an important tropical fruit consumed worldwide and grown in Italy only in Sicily, where the areas of the Tyrrhenian coast have proved to be suitable to produce valuable fruits. Mango fruit has a pleasant aroma and taste, which are important qualities for consumer’s sensorial acceptance. However, they are highly perishable, prone to progressive undesired changes if stored untreated, resulting in around 25% postharvest losses, which is further increased during storage and transportation. An alternative for reducing the above-mentioned undesired changes is the dehydration of the cut fruit, which reduce the fruit water activity, thereby avoiding the deteriorative …