Search results for "riz"
showing 10 items of 9613 documents
Carboxylate catalyzed isomerization of β,γ‐unsaturated N-acetylcysteamine thioesters
2022
We demonstrate herein the capacity of simple carboxylate salts – tetrametylammonium and tetramethylguanidinium pivalate – to act as catalysts in the isomerization of β,γ-unsaturated thioesters to α,β-unsaturated thioesters. The carboxylate catalysts gave reaction rates comparable to those obtained with DBU, but with fewer side reactions. The reaction exhibits a normal secondary kinetic isotope effect ( k 1H / k 1D = 1.065±0.026) with a β,γ−deuterated substrate. Computational analysis of the mechanism provides a similar value ( k 1H / k 1D = 1.05) with a mechanism where γ-reprotonation of the enolate intermediate is rate determining. peerReviewed
Oxidation-responsive and "clickable" poly(ethylene glycol) via copolymerization of 2-(methylthio)ethyl glycidyl ether
2016
Poly(ethylene glycol) (PEG) is a widely used biocompatible polymer. We describe a novel epoxide monomer with methyl-thioether moiety, 2-(methylthio)ethyl glycidyl ether (MTEGE), which enables the synthesis of well-defined thioether-functional poly(ethylene glycol). Random and block mPEG-b-PMTEGE copolymers (Mw/Mn = 1.05-1.17) were obtained via anionic ring opening polymerization (AROP) with molecular weights ranging from 5 600 to 12 000 g·mol-1. The statistical copolymerization of MTEGE with ethylene oxide results in a random microstructure (rEO = 0.92 ± 0.02 and rMTEG E = 1.06 ± 0.02), which was confirmed by in situ 1H NMR kinetic studies. The random copolymers are thermorespon…
Carbon Nitride-Based Catalysts for High Pressure CO2 Photoreduction
2022
In the current research, the productivity of CO2 photoreduction has been boosted by performing the reaction in an innovative photocatalytic reactor, which allows for operation up to 20 bar. A set of photocatalysts were used, including three types of pristine TiO2, i.e., one commercially prepared (Evonik P25), one home-prepared by flame spray pyrolysis (FSP), and one obtained by the hydrolysis of TiCl4 (TiO2exCl), a bare thermo-exfoliated carbon nitride (C3N4-TE), and binary materials composed of TiO2 and C3N4-TE. The photoreduction was carried out in water at pH 14 and in the presence of Na2SO3 as a hole scavenger. Hydrogen and very small amounts of CO were detected in the head space of the…
Authorized authentication evaluation framework for constrained environments
2016
Internetin kasvu ei perustu tällä hetkellä vain uusien solmujen määrään, vaan Internet on levittäytymässä aivan uusille alueille. Viimeaikoina erilaiset tavat kerätä tietoa ja ohjata laitteita uusin tavoin ovat yleistyneet esimerkiksi teollisuudessa, kaupunkiympäristöjen melun ja saasteiden seurannassa. Lisäksi käsitteet älykoti tai -kaupunki alkavat olla yleisesti tunnettuja. Nykyinen kasvu näiden teknologioiden käytössä perustuu pitkälti laitteiden koon pienenemiseen ja hintojen laskuun. Jotta Esineiden Internet pystyy kasvamaan merkittävällä tavalla, laitteiden fyysisten kokojen ja hintojen tulisi pysyä matalalla tasolla tai laskea edelleen. Pieni koko ja hinta tarkoittaa kuitenkin usein…
Productive, Commercial and Qualitative characterization of tomato sicilian landraces
2010
Una tomba di bambini dalla necropoli orientale di Polizzello
2019
The last excavation (2004-2006) in the eastern necropolis of Polizzello (CL) allowed to complete the excavation of this important funerary area and to discover a grave (No 2/2004) containing over 100 dead children. It represents a privileged observatory for the study of childhood in the indigenous world of Sicily. The structure of the tomb, the relative and absolute chronology, the composition of the kit with its symbolic value and the mode of deposition of the buried are analyzed, thanks to the data of the stratigraphic excavation. The hypotheses on causes of deaths are based on anthropological and paleobiological studies conducted on skeletal finds, while some final considerations concern…
Estudio radiológico laríngeo en pacientes sometidos a tiroplastia de medialización mediante la técnica de Montgomery modificada por Zapater
2023
Objetivos: el propósito de este estudio es analizar las variables radiológicas y clínicas que pudieran influir en los resultados tras una tiroplastia de medialización de Montgomery modificada por Zapater en el tratamiento de la parálisis unilateral de cuerda vocal Material y métodos: se trata de un estudio retrospectivo de 24 pacientes sometidos a tiroplastia que dividimos en un grupo de resultados óptimos (sin disfonía) y un grupo de resultados subóptimos. Se examinan medidas de la prótesis respecto al marco laríngeo mediante TC y variables clínicas y fonatorias: edad, sexo, aumento absoluto del TMF, disminución relativa del VHI-30 y los ítems G, R y B de la escala GRBAS de Hirano. Se empl…
A NOVEL APPROACH TO FULLY CHARACTERIZE FIBER NETWORK MORPHOLOGY OF PLANAR FIBROUS TISSUES AND SCAFFOLDS
2011
Comprendere come la struttura di uno scaffold influenzi la morfologia cellulare e predirne il comportamento meccanico sono divenuti obiettivi fondamentali nello sviluppo dei tessuti ingegnerizzati. In questo studio si presenta un algoritmo innovativo basato su analisi d’immagine. Vengono introdotti descrittori di micro architettura che identificano univocamente la topologia della rete di fibre: orientamento delle fibre, connettività, densità spaziale delle intersezioni e diametro. Le prestazioni dell’algoritmo sono state valutate utilizzando immagini di microscopio a scansione elettronica (SEM) di (1) scaffolds in poliestere uretano-urea prodotti per elettrospinning, (2) gel di collagene se…
Regularizācijas filtru salīdzinošā analīze 3D konstrukciju topoloģijas optimizācijai
2015
Darbs ir veltīts topoloģijas optimizācijas izpētei un tās regulējošo filtru salīdzinošai analīzei, izmantojot 3D konstrukcijas. Darbā tiek apskatīti divi filtri – jūtīguma filtrs un Gausa filtrs. Ar matemātiskām metodēm tiek aprēķinātas filtru rādītās izmaiņas konstrukcijā, ja tiek mainīti filtru parametri. Darba galvenais mērķis ir izpētīt šos divus filtrus un veikt to salīdzinošo analīzi, vērtējot filtru darbības precizitāti, rēķināšanas laiku un mērķa funkcijas minimālās vērtības. Darbā tiek apskatīti vairāki 3D konstrukciju piemēri, piemēram, Rīgas dzelzceļa tilts. Tika iegūti rezultāti, kas nākotnē tiks izmantoti topoloģijas optimizācijas regularizācijas filtru plašākai izpētei un piel…
Nazwy krzewów w śląskiej toponimii
2017
The paper deals with geographical names in Silesia deriving from shrub species names. 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 those names from the existing collection of the names derived from the appellatives which are for certain reasons important and valuable for them. For example, the following names of shrubs become a productive toponymic base: hazel, blueberry, rose; they belong to the basic categorization level and are important for the rural community due to their usable and practical significance (in construction a…