Search results for "RIZ"
showing 10 items of 9613 documents
Highly Syndiotactic or Isotactic Polyhydroxyalkanoates by Ligand-Controlled Yttrium-Catalyzed Stereoselective Ring-Opening Polymerization of Function…
2017
International audience; Reported herein is the first stereoselective controlled ROP of a specific family of racemic functional β-lactones, namely 4-alkoxymethylene-β-propiolactones (BPL(OR) s). This process is catalyzed by an yttrium complex stabilized by a nonchiral tetradentate amino alkoxy bisphenolate ligand _ONOO(R'2) ₍2-) , which features both a good activity and a high degree of control over the molar masses of the resulting functional poly(3-hydroxyalkanoate)s. A simple modification of the R' substituents in ortho and para position on the ligand platform allows for a complete reversal from virtually pure syndioselectivity (Ps up to 0.91 with R'=cumyl) to very high isoselectivity (Pi…
Diferencias de sexo en estrategias de aprendizaje de estudiantes online.
2018
Analizamos aquí las estrategias de aprendizaje empleadas por estudiantes universitarios, de modalidad online, en función del género. En primer lugar, se realiza una exhaustiva revisión de publicaciones que comparten el objeto de estudio, la mayoría de ellas difundidas en la última década y señalando los principales hallazgos de estas investigaciones. El objetivo del estudio es analizar tanto las estrategias empleadas como desvelar semejanzas y diferencias con respecto a modalidades presenciales. Metodológicamente optamos por realizar un diseño multimétodo, en el que el análisis cualitativo tiene como finalidad contribuir a la evaluación e interpretación de los resultados de tipo cuantitativ…
Cuénteme un cuento / 1
2008
Nazwy drzew w śląskiej toponimii
2015
The paper deals with geographical names in Silesia deriving from the names of tree species. An analysis of the names derived from appellatives, allows for a reconstruction of the categorization methods of the world, anthropological conceptualization, and a popular image of reality. Name creators choose names derived from the appellatives which are for certain reasons important and valuable for them, from the existing collection of names. For example, the following names of trees and shrubs become a productive toponymic base: oak, birch, alder; they belong to the basic categorization level and are important for the rural community due to their usable and practical significance (in constructi…
Caratterizzazione di mattoni in terra cruda di età ellenistico-romana dall’area archeologica di Solunto (Palermo) e di provini ottenuti con materie p…
2016
Nel presente lavoro sono riportati i dati relativi alla caratterizzazione di suoli prelevati nell’area perimetrale del sito archeologico di Solunto ed utilizzati per la riproduzione di mattoni in “terra cruda” confrontabili con quelli di età ellenistico - romana in opera in diverse unità abitative dell’insediamento. L’obiettivo di questo studio è, pertanto, quello di verificare l’area di provenienza delle materie prime originariamente utilizzate per la manifattura dei mattoni soluntini e di predisporre la base per una successiva sperimentazione atta alla valutazione dell’efficacia di procedure e prodotti per il futuro consolidamento delle strutture murarie del sito archeologico. La ricerca …
Eumelanin Coating of Silica Aerogel by Supercritical Carbon Dioxide Deposition of a 5,6-Dihydroxyindole Thin Film
2018
Eumelanin integration in silica aerogel (SA) was achieved via supercritical adsorption of 5,6-dyhydroxyindole (DHI) from CO2. Notably, after the supercritical treatment, DHI evolved towards spontaneous polymerization, which resulted in uniform pigment development over the SA. The new material was characterized for its morphological and physicochemical properties, disclosing the formation of a eumelanin-like coating, as confirmed by UV&ndash
Statistical check of USLE-M and USLE-MM to predict bare plot soil loss in two Italian environments
2018
The USLE-M and the USLE-MM estimate event plot soil loss. In both models, the erosivity term is given by the runoff coefficient, QR, times the single-storm erosion index, EI30. In the USLE-MM, QREI30is raised to an exponent b1> 1 whereas b1= 1 is assumed in the USLE-M. Simple linear regression analysis can be applied to parameterize both models, but logarithmically transformed data have to be used for USLE-MM. Parameterizing the USLE-MM with nonlinear regression of untransformed data could be a more appropriate procedure. A statistical check of the two suggested models (USLE-M and USLE-MM), considering two alternative parameterization procedures for the USLE-MM, was carried out for the Mass…
Structural analysis, phase stability and electrochemical characterization of Nb doped BaCe0.9Y0.1O3−x electrolyte for IT-SOFCs
2012
Abstract To improve the chemical stability of high temperature proton conductors based on barium cerate, electrolyte powders doped with different amounts of niobium were synthesized by the citrate–nitrate auto-combustion method. Pure single phases of BaCe 0.9− x Nb x Y 0.1 O 3− x (BCYN, 0.03 ≤ x ≤ 0.12) were obtained by thermal treatment at 1000 °C. Sintering at 1450 °C for 10 h produced dense pellets. X-ray absorption spectroscopy allowed to define the dopant ion insertion site and the co-dopant valency. Treatments in pure CO 2 atmosphere at 700 °C for 3 h and subsequent XRD analysis were carried out to probe the chemical stability of the produced electrolytes. The influence of the prese…
Overview and Update on Extracellular Vesicles: Considerations on Exosomes and their Application in Modern Medicine
2022
In recent years, there has been a rapid growth in the knowledge of cell-secreted extracellular vesicle functions. They are membrane enclosed and loaded with proteins, nucleic acids, lipids, and other biomolecules. After being released into the extracellular environment, some of these vesicles are delivered to recipient cells; consequently, the target cell may undergo physiological or pathological changes. Thus, extracellular vesicles as biological nano-carriers, have a pivotal role in facilitating long-distance intercellular communication. Understanding the mechanisms that mediate this communication process is important not only for basic science but also in medicine. Indeed, extracellular …
Multiband variability studies and novel broadband SED modeling of Mrk 501 in 2009
2017
Astronomy and astrophysics 603, A31 (2017). doi:10.1051/0004-6361/201629540