Search results for " pec"
showing 10 items of 156 documents
Synthesis of Nd:YAG nanopowder using the citrate method with microwave irradiation
2010
Abstract Nd:YAG nanopowders were prepared using the Pechini process with microwave irradiation ( MWs ). A reference sample was also prepared using conventional heating. XRD pattern analysis showed that nanopowder obtained by means of conventional heating and calcination for 1 h at 900 °C has a structure made up of the garnet phase together with the hexagonal phase that disappeared after two additional hours of thermal treatment. The MWs powder calcined for 1 h consists of the single garnet phase. SAXS data analysis indicated that nanoparticles are characterized by a sharp interface. TEM investigation showed crystalline particles with remarkable agglomeration in both samples, although a more…
Dispersions of Nanoclays of Different Shapes into Aqueous and Solid Biopolymeric Matrices. Extended Physicochemical Study
2010
Dispersions of nanofillers into aqueous and solid biopolymeric matrices were studied from the physicochemical viewpoint. This work was carried out based on the idea that the combination of biopolymers, derived from renewable resources, and nanofiller, environmentally friendly, may form a new generation of nanomaterials with excellent and unique properties at low cost. To this purpose, two pectins with different degrees of methyl esterification and nanoclays like halloysite and laponite RD were selected. The thermodynamic and structural studies on the aqueous mixtures of pectin and nanoclay were able to discriminate the interactions, which control the adsorption of pectin onto the filler and…
Silica-coated calcium pectinate beads for colonic drug delivery
2013
The aim of this work is to develop novel organic-inorganic hybrid beads for colonic drug delivery. For this purpose, calcium pectinate beads with theophylline are prepared by a cross-linking reaction between amidated low-methoxyl pectin and calcium ions. The beads are then covered with silica, starting from tetraethyoxysilane (TEOS), by a sol-gel process. The influence of TEOS concentration (0.25, 0.50, 0.75 and 1.00 M) during the process is studied in order to modulate the thickness of the silica layer around the pectinate beads and thus to control the drug release. The interactions between the silica coating and the organic beads are weak according to the physicochemical characterizations…
Coffee grounds as filler for pectin: Green composites with competitive performances dependent on the UV irradiation.
2017
Novel composite bioplastics were successfully prepared by filling pectin matrix with treated coffee grounds. The amount of coffee dispersed into the pectin was changed within a wide filler range. The morphology of the pectin/coffee hybrid films was studied by microscopic techniques in order to investigate their mesoscopic structure as well as the sizes distribution of the particles dispersed into the matrix. The micrographs showed that the coffee grounds are uniformly dispersed within the polymeric matrix. The morphological characteristics of the biocomposite films were correlated to their properties, such as wettability, water uptake, thermal behavior and mechanical performances. Dynamic m…
The helminth community of the Iberian hare, Lepus granatensis (Lagomorpha: Leporidae), in the province of Granada, Spain
2014
Abstract The helminth community of the Iberian hare, Lepus granatensis, in the southern Spanish province of Granada was analysed, thorough the study of 487 individuals shot by hunters between November 1998 and October 1999. Six helminth species were found: Mosgovoyia pectinata (Cestoda); Trichostrongylus retortaeformis, Nematodiroides zembrae, Nematodirus sp., Passalurus ambiguus and Micipsella numidica (Nematoda). N. zembrae and M. pectinata (62.4 % and 17.2 %, respectively) were the only component species found. The predominance of helminth species with a direct life cycle is noteworthy. These two component species were significantly influenced by season of capture. Other factors, such as…
Las comunidades de Castilla (1520-1522) como conflicto intraurbano. Sus peculiaridades en el contexto político europeo
2021
En 1520 y 1521 las ciudades castellanas fueron escenario de enconados conflictos políticos que dieron lugar a la introducción de radicales cambios en el régimen de gobierno local. Como consecuencia por primera vez dichas ciudades ofrecieron evidentes paralelismos con las de otros ámbitos de Europa, en particular las alemanas, en las que durante los siglos XIv y Xv y en la primera mitad del XvI proliferaron las revueltas y disputas por el poder político urbano, que con frecuencia conllevaron la introducción de cambios constitucionales de calado. En este artículo el autor se ocupa de la identificación de los principales paralelismos y divergencias, o singularidades, de las ciudades castellana…
The 'Ndrangheta between imprisonment reality and organizational ideality: a psychological clinical research
2010
La mafia è un fenomeno complesso, pervasivo, agghiacciante che ha scomodato intelligenze, competenze, professionalità le più disparate. La scienza, in particolare quella clinico-psicologica, non può sottrarsi dall’apportare il suo contributo conoscitivo, coadiuvando il lavoro di contrasto attraverso strumenti culturali e d’intervento clinico-sociale. È necessario compiere un’analisi contingente e rigorosa, composita e approfondita, contestuale e storicizzata delle manifestazioni psichiche connesse al fenomeno mafioso. Il primo compito della psicologia clinica, in questo senso, è valutare lo spessore psicologico del fenomeno, le proporzioni del disagio sociale che esso ha generato, favorendo…
Variazioni sul tema del principio nominalistico
2014
Dall’utopia allo svuotamento del principio nominalistico: la reviviscenza della Kategorienlehre come instrumentum iudicis per il governo degli effett…
2014
La nota a sentenza trae origine da una recente nonché problematica pronuncia della Corte di Cassazione in materia di obbligazioni pecuniarie, offrendo alcuni spunti di riflessione sul tema della struttura e della disciplina dei debiti di valuta.
Economic and Technical Feasibility of Betanin and Pectin Extraction from Opuntia ficus-indica Peel via Microwave-Assisted Hydrodiffusion
2019
Investigating the feasibility of betanin and pectin extraction from Opuntia ficus-indica peel via microwave-assisted hydrodiffusion and gravity, this study identifies selected important economic and technical aspects associated with this innovative production route starting from prickly pear fruit discards. Which benefits would be derived from this process? Would production be limited to Opuntia-growing countries or, likewise to what happens with dried lemon peel chiefly imported from Argentina, would production take place abroad also? Can distributed manufacturing based on clean extraction technology compete with centralized production using conventional chemical processes?