Search results for "Silo"
showing 10 items of 412 documents
Silage of Prickly Pears (Opuntia spp.) Juice By-Products
2020
Simple Summary The cactus pear plant is a Cactaceae which originates from the Americas and is highly resistant to arid and hot environments. The plant is used as animal feedstuff in regions characterized by a lack of nutrient resources. In Italy, the fruits are known as prickly pears are usually eaten fresh by humans, and more recently have also started to be transformed into fruit juice. Various by-products (i.e., peel, pulp, and seeds) derived from the extraction of fruit juice are used for livestock feed due to their high amounts of fermentable structural carbohydrates. However, some of these by-products are difficult to conserve due to their high fermentability. The aim of the present s…
Formation of silicones mediated by the sponge enzyme silicatein-α
2010
The sponge-restricted enzyme silicatein-α catalyzes in vivo silica formation from monomeric silicon compounds from sea water (i.e. silicic acid) and plays the pivotal role during synthesis of the siliceous sponge spicules. Recombinant silicatein-α, which was cloned from the demosponge Suberites domuncula (phylum Porifera), is shown to catalyze in vitro condensation of alkoxy silanes during a phase transfer reaction at neutral pH and ambient temperature to yield silicones like the straight-chained polydimethylsiloxane (PDMS). The reported condensation reaction is considered to be the first description of an enzymatically enhanced organometallic condensation reaction.
Nuevas aportaciones al horizonte del bronce final de La Vital (Gandia, València)
2013
Durante las tareas de seguimiento arqueológico de las obras de construcción del Acceso Sur a Gandia se localizaron diferentes estructuras negativas datadas en el Bronce final ubicadas en el perímetro de protección del yacimiento de La Vital. Las estructuras documentadas corresponden a un lugar de hábitat fechado en estos momentos. En este trabajo presentamos los resultados de dicha actuación, valorándolos en el marco del desarrollo histórico de este periodo en el propio yacimiento y en la costa mediterránea peninsular.
Settlement, radiocarbon dates and craft productions during Late Neolithic and Bell Beaker periods in the ‘corredor de Montesa’ (Valencia, Spain). The…
2014
[EN] In this paper we present the results related to the excavation works conducted in Late Neolithic and Bell Beaker sites of Quintaret (Montesa, Valencia) and Corcot (l’Alcúdia de Crespins, Valencia), both in the middle valley of Canyoles river. The sites, neighboring each other, offer a quite different volume of information (Quintaret: 51 structures; Corcot: 4 structures). 14C dates allow us to define the occupation of this area of the valley along the first half of the III millennium cal BC. The presence of bell beaker ceramic in archaeological record of Quintaret is limited to just one structure (Q138), where at least 7 different vessels have been identified. Other prominent point of t…
Excavaciones arqueologicas en el yacimiento de Colata (Montaverner, València)
2008
Se exponen los resultados obtenidos después de los trabajos arqueológicos de urgencia llevados a cabo en el yacimiento de Colata, como consecuencia de las obras de ampliación del polígono industrial de la Cava en el municipio de Montavemer. El yacimiento, ubicado en el corazón de la Vall d' Albaida, se extiende por diversos bancales situados al este del tossalet del Calvari, que domina las fértiles tierras del Pla de la Colata, y muy cerca del punto en que el río Albaida y el Clariano unen sus aguas. En total se han encontrado restos en un área aproximada de 0.5 ha, pero el asentamiento pudo tener unas dimensiones mayores. Se han encontrado múltiples evidencias ligadas a lo que en la biblio…
Bimodal Acidity at the Amorphous Silica/Water Interface
2015
International audience; Understanding the microscopic origin of the acid base behavior of mineral surfaces in contact with water is still a challenging task, for both the experimental and the theoretical communities. Even for a relatively simple material, such as silica, the origin of the bimodal acidity behavior is still a debated topic. In this contribution we calculate the acidity of single sites on the humid silica surface represented by a model for the hydroxylated amorphous surface. Using a thermodynamic integration approach based on ab initio molecular dynamics, we identify two different acidity values. In particular, some convex geminals and some type of vicinals are very acidic (pK…
Zwitterionic codeine-derived methacrylate monoliths for enantioselective capillary electrochromatography of chiral acids and chiral bases
2018
Thiol-ene click reaction of N-acetyl-L-cysteine methyl ester to codeine, followed by reaction with allyl isocyanate and hydrolysis to the corresponding zwitterionic chiral selector and its subsequent bonding to the surface of a methacrylate monolith provided a new chiral capillary column for enantiomer separation of chiral acids and chiral bases. First, the epoxy groups of a poly(glycidyl methacrylate-co-ethylene dimethacrylate) monolith were converted into amine residues, followed by reaction with allylglycidyl ether. In this way, a spacer arm was bonded to the surface before coating and cross-linking poly(3-mercaptopropyl methylsiloxane) (PMPMS) via radical addition (thiol-ene click react…
Reinvestigation of the Pd-catalysed bis(silylation) of alkynes with 1,1,2,2-tetramethyl-1,2-bis(phenylthiomethyl)disilane: Unexpected formation of th…
2013
International audience; The bis(silylated) alkenes Z-(PhSCH2)Me2SiC(H)=C(Fc)SiMe2(CH2SPh) (2) and Z-(PhSCH2)Me2SiC(H)=C(bipheny)SiMe2(CH2SPh) (3) have been prepared by Pd-catalysed double silylation of ethynylferrocene and 4-ethynyl-1,1'-biphenyl in the presence of 1,1,2,2-tetramethyl-1,2-bis(phenylthiomethyl)disilane (1). A reinvestigation on the interaction of 1 with [PdCl2(PhCN)2] in technical-grade CH2Cl2 as solvent revealed competition between reduction to elemental palladium (due to oxidative addition of the Si-Si bond across Pd(II) and subsequent reductive elimination) and formation of an unusual eight-membered chelate complex cis-[PdCl2{(PhSCH2SiMe2)2O}] (4), which is fluxional in s…
Dynamic covalent urea bonds and their potential for development of self-healing polymer materials
2019
Self-healing polymer materials have drawn rapidly increasing interest over the last decade, and have been studied and used in an ever-increasing range of applications. Herein, we successfully make the covalent urea bond – a pinnacle of stability due to strong resonance effects – dynamic in nature through mediation of zinc salts. The dynamic covalent character of urea in the presence of zinc ions is confirmed through dissociation reaction experiments and quantum chemical calculations of small-molecule model urea compounds. In line with our experiments, the modelling results suggest that the presence of zinc ions speeds up the reaction of urea dissociation by two orders of magnitude via the f…
CCDC 795371: Experimental Crystal Structure Determination
2011
Related Article: J.Barjau, G.Schnakenburg, S.R.Waldvogel|2011|Angew.Chem.,Int.Ed.|50|1415|doi:10.1002/anie.201006637