Search results for "silo"
showing 10 items of 412 documents
Stable-bond polymeric reversed-phase/weak anion-exchange mixed-mode stationary phases obtained by simultaneous functionalization and crosslinking of …
2019
Abstract A polymeric reversed-phase/weak anion exchange (Poly-RP/WAX) mixed-mode stationary phase has been prepared by coating of a poly(3-mercaptopropyl)methylsiloxane film on vinyl-modified silica (100 A, 5 μm) and simultaneous in situ functionalization with N-(10-undecenoyl)-3-aminoquinuclidine as well as crosslinking to the vinyl silica surface by solventless thiol-ene double click reaction. Such bonding chemistry showed greatly enhanced stability compared to brush-type analogs with bifunctional siloxane bonding to silica. Solid-state 29Si-CP/MAS NMR confirmed the immobilization of the siloxane layer. pH-Dependent ζ-potential determinations revealed a high anion-exchange capacity over t…
Surface-anchored counterions on weak chiral anion-exchangers accelerate separations and improve their compatibility for mass-spectrometry-hyphenation
2017
In the present work we propose new variants of chiral stationary phases (CSP) with tert-butylcarbamoylquinine (tBuCQN) as chiral selector molecule. Four tBuCQN-CSPs with distinct bonding chemistries are compared in terms of their pH-dependent surface charge by ζ-potential determinations, by achiral and chiral liquid chromatographic tests and LC-ESI-MS hyphenation. In one embodiment tBuCQN was immobilized on 3-mercaptopropylmethylsilyl-modified silica by thiol-ene click reaction (brush type CSP with selector coverage of 0.38mmol/g). In another embodiment, poly-(3-mercaptopropyl)-methylsiloxane was coated onto vinylized silica particles in presence of tBuCQN and radical initiator. The tBuCQN …
Chemical and antifungal investigations of six Lippia species (Verbenaceae) from Brazil
2012
Made available in DSpace on 2013-09-27T14:52:47Z (GMT). No. of bitstreams: 1 WOS000310396700165.pdf: 536437 bytes, checksum: d267984ddfcb57d1406b069856adcc25 (MD5) Previous issue date: 2012-12-01 Made available in DSpace on 2013-09-30T19:10:31Z (GMT). No. of bitstreams: 1 WOS000310396700165.pdf: 536437 bytes, checksum: d267984ddfcb57d1406b069856adcc25 (MD5) Previous issue date: 2012-12-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T14:20:39Z No. of bitstreams: 1 WOS000310396700165.pdf: 536437 bytes, checksum: d267984ddfcb57d1406b069856adcc25 (MD5) Made available in DSpace on 2014-05-20T14:20:39Z (GMT). No. of bitstreams: 1 WOS000310396700165.pdf: …
Ionic liquids versus amine solutions in biogas upgrading: the level of volatile organic compounds
2013
Background: This article provides information related to the occurrence of volatile organic compounds before and after biogas purification, by means of both aqueous amine solutions and ionic liquids. Results & discussion: Encouraging results were obtained. Under the experimental conditions, 1-butyl-3-methylimidazolium acetate ionic liquid appeared to perform at least two-times better than aqueous amines solutions, since it captured 65 wt% of the identified volatile organic compounds, while aqueous amine solutions retained around 35 wt% only. However, in the case of octamethylcyclotetrasiloxane and dichlorobenzene, aqueous amine solutions rendered better purification performance and diminish…
Otra política d asilo es posible en Europea. Una breve comparación entre la UE y Canadá.
2016
La situación que ha generado en la Unión Europea la mal denominada “crisis de los refugiados”, pone en evidencia hasta qué punto ha fracasado el denominado Sistema Común de Asilo. Múltiples factores han concurrido, durante dos décadas, hasta llegar a lo que puede considerarse una desnaturalización del asilo. Para reivindicar la necesidad de protección internacional como un derecho en el contexto europeo, es interesante analizar, como propone este trabajo, los múltiples factores que han concurrido para que el sistema Dublín no llegue a implementarse. Dicho estudio, además, puede completarse desde una perspectiva comparada atendiendo al caso canadiense. La confrontación entre algunas de las m…
Diritti, sicurezza, solidarietà e responsabilità nella protezione delle persone migranti
2018
Le crisi migratorie e l’onda lunga del populismo nei sistemi politici nazionali contro la ricerca dell’equilibrio fra diritti, sicurezza, solidarietà e responsabilità; la Carta dei diritti fondamentali dell’Unione Europea ed il rafforzamento del principio di solidarietà fra Stati; la ricerca dell’equilibrio: il contributo del costituzionalismo. L’esperienza italiana: diritti, solidarietà, responsabilità e sicurezza.
"Table 1" of "Measurement of Upsilon production in 7 TeV pp collisions at ATLAS"
2013
Corrected cross-section measurements in the isotopic spin-alignment scenario. The second (sys) error is the uncertainty in the luminosity.
Development of a simulation chamber for the evaluation of dermal absorption of volatile organic compounds
2020
Abstract An exposition chamber has been designed and developed for the production of contaminated atmospheres with fixed and known concentration of volatile organic compounds. The proposed chamber has been evaluated for the determination of in-vitro diffusion parameters, such as flux and lag time for benzene, toluene, ethylbenzene, and xylenes (BTEX). Polydimethylsiloxane (PDMS) and Strat-M® membranes were evaluated, including the effect of membrane thickness, from 0.5 to 3.0 mm, on the diffusion parameters. The obtained flux values and lag times, ranged from 0.2 to 1.5 μg cm−2 h−1 and from 10 to 130 min, respectively, for studies performed at a BTEX concentration of 51 μg L−1 in air. Diffe…
The neolithic settlement of Limoneros (Elche, Alicante)
2020
[EN] This paper shows the results of rescue archaeology campaigns undertaken on the site of Limoneros, an open-air settlement located to the south of Elche (Alicante), in the alluvial plain of the Vinalopó river and dated on the first half of the 5th millennium cal BC. The settlement entails different negative structures, including two stretches of ditch, silos and basins, structures finally reused as a waste area. The analysis of the recovered evidences allows the characterization of the activities developed by a farming community in a territory articulated by the river Vinalopó, where other settlements dated back to the same period have been documented. Therefore, Limoneros supplies relev…
A solid device based on doped hybrid composites for controlling the dosage of the biocide N-(3-aminopropyl)-N-dodecyl-1,3-propanediamine in industria…
2015
A colorimetric composite device is proposed to determine the widely used biocide N-(3-aminopropyl)-N-dodecyl-1,3-propanediamine (ADP).This sensing device is based on a film of 1,2-Naphthoquinone-4-sulfonate (NQS) embedded into polydimethylsiloxane-tetraethylortosilicate-SiO2 nanoparticles composite (PDMS-TEOS-SiO2NPs). Semiquantitative analysis can be performed by visual inspection. Digitalized image or diffuse reflectance (DR) measurements can be carried out for quantitative analysis. Satisfactory detection limit (0.018%, w/v) and relative standard deviations <12% were achieved. The proposed device has been applied for the determination of ADP in detergent industrial formulations with reco…