Search results for "lcsh:Technology"
showing 10 items of 550 documents
Creep Behavior of Poly(lactic acid) Based Biocomposites
2017
Polymer composites containing natural fibers are receiving growing attention as possible alternatives for composites containing synthetic fibers. The use of biodegradable matrices obtained from renewable sources in replacement for synthetic ones is also increasing. However, only limited information is available about the creep behavior of the obtained composites. In this work, the tensile creep behavior of PLA based composites, containing flax and jute twill weave woven fabrics, produced through compression molding, was investigated. Tensile creep tests were performed at different temperatures (i.e., 40 and 60 °C). The results showed that the creep behavior of the composites is strongly inf…
Influence of MeV H+ ion beam flux on cross-linking and blister formation in PMMA resist
2012
In soft lithography, a pattern is produced in poly(dimethylsiloxane) (PDMS) elastomer by casting from a master mould. The mould can be made of poly(methylmethacrylate) (PMMA) resist by utilising either its positive or negative tone induced by an ion beam. Here we have investigated the irradiation conditions for achieving complete cross-linking and absence of blister formation in PMMA so that its negative characteristic can be used in making master moulds. PMMA thin films approximately 9 µm thick on Si were deposited by spin coating. The 2-MeV H+ ion beam was generated using a 1.7-MV tandem Tandetron accelerator. The beam was collimated to a 500×500 µm2 cross section using programmable proxi…
Green Roofs as Effective Tools for Improving the Indoor Comfort Levels of Buildings—An Application to a Case Study in Sicily
2020
In the line of pursuing better energy efficiency in human activities that would result in a more sustainable utilization of resources, the building sector plays a relevant role, being responsible for almost 40% of both energy consumption and the release of pollutant substances in the atmosphere. For this purpose, techniques aimed at improving the energy performances of buildings&rsquo
Valencian Network of Educational Innovation in Optics
2014
[EN] The Valencian Network of Educational Innovation in Optics consists of three groups from the Universitat de València, Universitat Jaume I, and Universitat Politècnica de València. The participants in the network present an extensive background on performing actions to improve teaching practice. They have been involved for years in scientific outreach activities and in a number of educational innovation projects, which have developed innovative teaching materials. With the aim of sharing their experience and enhance their performance, the three groups have decided to join forces to become a Network of Educational Innovation whose main projects are described in this communication.
Reinforcement Efficiency of Cellulose Microfibers for the Tensile Stiffness and Strength of Rigid Low-Density Polyurethane Foams
2020
Rigid low-density closed-cell polyurethane (PU) foams are widely used in both thermal insulation and structural applications. The sustainability of PU foam production can be increased by using bio-based components and fillers that ensure both enhanced mechanical properties and higher renewable material content. Such bio-based foams were produced using polyols derived from rapeseed oil and microcrystalline cellulose (MCC) fibers as filler. The effect of MCC fiber loading of up to 10 wt % on the morphology, tensile stiffness, and strength of foams has been evaluated. For estimation of the mechanical reinforcement efficiency of foams, a model allowing for the partial alignment of filler fibers…
Microbial Fuel Cell with Ni–Co Cathode Powered with Yeast Wastewater
2018
Wastewater originating from the yeast industry is characterized by high concentration of pollutants that need to be reduced before the sludge can be applied, for instance, for fertilization of croplands. As a result of the special requirements associated with the characteristics of this production, huge amounts of wastewater are generated. A microbial fuel cell (MFC) forms a device that can apply wastewater as a fuel. MFC is capable of performing two functions at the same time: wastewater treatment and electricity production. The function of MFC is the production of electricity during bacterial digestion (wastewater treatment). This paper analyzes the possibility of applying yeast wastewate…
Activity of Antimicrobial Silver Polystyrene Nanocomposites.
2012
A simple technique based on doping polymers within situgenerated silver nanoparticles (Ag/PS films) has been developed. In particular, an antiseptic material has been prepared by dissolving silver 1,5-cyclooctadiene-hexafluoroacetylacetonate in amorphous polystyrene, and the obtained solid solution has been heated for ca. 10 s at a convenient temperature (180°C). Under such conditions the metal precursor decomposes producing silver atoms that diffuse into the polymer and clusterize. The antimicrobial characteristics of the resulting polystyrene-based material have been accurately evaluated towardEscherichia coli (E. coli)comparing the cytotoxicity effect of 10 wt.% and 30 wt.% (drastic and …
(+)-(E)-Chrysanthenyl Acetate: A Molecule with Interesting Biological Properties Contained in the Anthemis secundiramea (Asteraceae) Flowers
2020
Anthemis secundiramea is a perennial herb native widespread throughout the Mediterranean basin. The oil obtained from the flowers of this plant has antimicrobial properties against gram-positive and -negative bacteria, and inhibits the biofilm formation. The extract of A. secundiramea also has antioxidant activity&mdash
Zebrafish Fins as a Model System for Skeletal Human Studies
2007
Recent studies on the morphogenesis of the fins ofDanio rerio(zebrafish) during development and regeneration suggest that a number of inductive signals involved in the process are similar to some of those that affect bone and cartilage differentiation in mammals and humans. Akimenko et al. (2002) has shown that bone morphogenetic protein-2b (BMP2b) is involved in the induction of dermal bone differentiation during fin regeneration. Many other groups have also shown that molecules from the transforming growth factor-beta superfamily (TGFβ), including BMP2, are effective in promoting chondrogenesis and osteogenesisin vivoin higher vertebrates, including humans. In the present study, we review…
On-line quizzes to evaluate comprehension and integration skills
2016
[EN] This work demonstrates the use of a 2.0 tool, namely, Socrative, to evaluate one of the cross-curricular competences indicated by the Universitat Politècnica de València, specifically, comprehension and integration. It has been applied to the courses in different areas: sciences, engineering and languages. As part of its implementation, activities were proposed that could be done at the beginning, during or at the end of the class to, on the one hand, help students acquire the knowledge associated with the course(s), and on the other, gather evidence that demonstrates acquisition of said competence. The results show a high level of satisfaction by the students with the use of the Socra…