Search results for "48"
showing 10 items of 1388 documents
Regenerable ZnO/GaAs Bulk Acoustic Wave Biosensor for Detection of Escherichia coli in “Complex” Biological Medium
2021
A regenerable bulk acoustic wave (BAW) biosensor is developed for the rapid, label-free and selective detection of Escherichia coli in liquid media. The geometry of the biosensor consists of a GaAs membrane coated with a thin film of piezoelectric ZnO on its top surface. A pair of electrodes deposited on the ZnO film allows the generation of BAWs by lateral field excitation. The back surface of the membrane is functionalized with alkanethiol self-assembled monolayers and antibodies against E. coli. The antibody immobilization was investigated as a function of the concentration of antibody suspensions, their pH and incubation time, designed to optimize the immunocapture of bacteria. The perf…
Filling of Mater-Bi with Nanoclays to Enhance the Biofilm Rigidity
2018
We investigated the efficacy of several nanoclays (halloysite, sepiolite and laponite) as nanofillers for Mater-Bi, which is a commercial bioplastic extensively used within food packaging applications. The preparation of Mater-Bi/nanoclay nanocomposite films was easily achieved by means of the solvent casting method from dichloroethane. The prepared bio-nanocomposites were characterized by dynamic mechanical analysis (DMA) in order to explore the effect of the addition of the nanoclays on the mechanical behavior of the Mater-Bi-based films. Tensile tests found that filling Mater-Bi with halloysite induced the most significant improvement of the mechanical performances under traction force, …
The Use of Some Clay Minerals as Natural Resources for Drug Carrier Applications
2018
The goal of modern research is to use environmentally preferable materials. In this context, clay minerals are emerging candidates for their bio- and ecocompatibility, low cost and natural availability. Clay minerals present different morphologies according to their layer arrangements. The use of clay minerals, especially in biomedical applications is known from ancient times and they are regaining attention in recent years. The most representative clay minerals are kaolinit, montmorillonite, sepiolites and halloysite. This review summarizes some clay minerals and their derivatives for application as nanocontainer for biologically active species.
Organo-Clay Nanomaterials Based on Halloysite and Cyclodextrin as Carriers for Polyphenolic Compounds
2018
Hybrid material based on halloysite covalently linked to a hyper-reticulated cyclodextrin network was investigated as a potential carrier for polyphenolic compounds. The absorption ability of the hybrid system was studied in different pH conditions as well as the kinetic release of curcumin, chosen as a drug model. A preliminary study was performed to assess the antioxidant capacity of the obtained carrier. The obtained results highlighted that the curcumin molecule can have sustained release from the carrier over the time, retaining its antioxidant properties due to the combination of two different host systems that give rise to an hyper-reticulated structure, allowing an increase in the d…
Effect of ultraviolet and moisture action on biodegradable polymers and their blend
2020
In this work, the suitability of polylactic acid (PLA), polybutylene adipate terephthalate (PBAT) and PBAT/PLA blend samples to outdoor applications were investigated in terms of mechanical, morphological and visual properties in presence of ultraviolet action and water, finding that PLA in particular can be actually considered for such applications.
An aging evaluation of the bearing performances of glass fiber composite laminate in salt spray fog environment
2019
The aim of the present paper is to assess the bearing performance evolution of pinned, glass-composite laminates due to environmental aging in salt-spray fog tests. Glass fibers/epoxy pinned laminates were exposed for up to 60 days in salt-spraying, foggy environmental conditions (according to ASTM B117 standard). In order to evaluate the relationship between mechanical failure mode and joint stability over increasing aging time, different single lap joints, measured by the changing hole diameter (D), laminate width (W) and hole free edge distance (E), were characterized at varying aging steps. Based on this approach, the property-structure relationship of glass-fibers/epoxy laminates was a…
Sustainable metabolic engineering for sustainability optimisation of industrial biotechnology
2021
Industrial biotechnology represents one of the most innovating and labour-productive industries with an estimated stable economic growth, thus giving space for improvement of the existing and setting up new value chains. In addition, biotechnology has clear environmental advantages over the chemical industry. Still, biotechnology’s environmental contribution is sometimes valued with controversy and societal aspects are frequently ignored. Environmental, economic and societal sustainability of various bioprocesses becomes increasingly important due to the growing understanding about complex and interlinked consequences of different human activities. Neglecting the sustainability issues in th…
A Self-Adapting Approach for Forecast-Less Scheduling of Electrical Energy Storage Systems in a Liberalized Energy Market
2013
In this paper, an original scheduling approach for optimal dispatch of electrical Energy Storage Systems (ESS) in modern distribution networks is proposed. The control system is based on fuzzy rules and does not use forecasts since it repairs the past history according to the real time data on the electrical energy cost, renewable energy production and load. When the system detects a worsening of performances, the fuzzy logic rule-based control system self-adapts its membership functions using an economic indicator. The common use, in the relevant literature, of forecasted values in such systems can lead to large errors and economic losses. Moreover the speed of calculation guaranteed by th…
Brief an Karl Axel Christer Freiherr von Bruiningk
1839
Ms. 930a, Nr. 6b, Bl. 19r-19v Merkel, Garlieb H. Brief an Karl Axel Christer Freiherr von Bruiningk, [Depkinshof ?], [bez datuma; ohne Datum, pēc / nach 1839] Autora rokraksts / Autograph, vācu val. / Deutsch, [2] lpp. / S. Attēlu numuri / Bildnummern: 930a-006b-1 – 930a-006b-2 In dem undatierten Entwurf einer Antwort auf einen Brief Bruiningks [womit der unter Ms. 930a, Nr. 6a gemeint wird, bleibt noch unklar] lobt Merkel dessen Einsatz für die Bauernbefreiung. Das Problem des fehlenden Grundbesitzes für die freigelassenen Bauern sei ein Grund für die wirtschaftliche Rückständigkeit der „vaterländische[n] Provinzen“. Selbst in Posen (Preußen) und Galizien (Österreich) hätte die wirtschaftl…
Imatges del món i miralls literaris. L'escriptura metaficcional en l'obra de Carme Riera
2021
L'article proposa una anàlisi, com a eix vertebrador de la literatura de Carme Riera, dels elements que, a l'interior de la diègesi, giren l'atenció cap a la mateixa condició literària del text i cap als mecanismes de construcció i de funcionament que li són propis; és a dir, d'aquells elements que posen de manifest el caràcter ficcional de l’obra i mitjançant els quals s'hi planteja un pacte metaficcional. L'autoconsciència i l'autoreferencialitat del text metaficcional trenquen amb la il·lusió mimètica pròpia del pacte realista per a plantejar una reflexió sobre l'artifici dels sistemes de captació del real per part de la literatura, deixant al descobert els límits i els codis que regeixe…