Search results for "salt"
showing 7 items of 1157 documents
Synthesis and Structure-Affinity Relationships of Spirocyclic Benzopyrans with Exocyclic Amino Moiety
2019
σ1 and/or σ2 receptors play a crucial role in pathological conditions such as pain, neurodegenerative disorders, and cancer. A set of spirocyclic cyclohexanes with diverse O-heterocycles and amino moieties (general structure III) was prepared and pharmacologically evaluated. In structure-activity relationships studies, the σ1 receptor affinity and σ1:σ2 selectivity were correlated with the stereochemistry, the kind and substitution pattern of the O-heterocycle, and the substituents at the exocyclic amino moiety. cis-configured 2-benzopyran cis-11b bearing a methoxy group and a tertiary cyclohexylmethylamino moiety showed the highest σ1 affinity ( Ki = 1.9 nM) of this series of compounds. In…
Task-Specific Organic Salts and Ionic Liquids Binary Mixtures: A Combination to Obtain 5-Hydroxymethylfurfural From Carbohydrates
2019
The increase in energy demand and depletion of fossil fuels are among major issues of modern society. Valorization and transformation of raw materials in products of industrial value represents a challenge. This justifies the growing interest of scientific research towards the identification of suitable media and methodologies able to pursue above goals, paying attention to matter of sustainability. On this subject, we studied sulfonic-acid functionalized diimidazolium salts as catalysts for the conversion of fructose and sucrose to 5-hydroxymethylfurfural (5-HMF) in an ionic liquid mixture. In general, using these salts allowed us to obtain 5-HMF in good yields from both substrates in mild…
Phase equilibria of Pantelleria trachytes (Italy): constraints on pre-eruptive conditions and on the metaluminous to peralkaline transition in silici…
2018
Pantelleria Island is the type locality of pantellerite, an iron and alkali-rich rhyolite (P.I=molar Na2O+K2O/Al2O3 >1.05). Peralkaline rhyolites (i.e pantellerite and comendite) and trachytes usually represent the felsic end-members in continental rift systems (e.g., Pantelleria, Tibesti, Ethiopia, Afar, Kenya, Bain and Range, South Greenland) and in oceanic sland settings (Socorro Is., Easter Is., Iceland and Azores). The origin of peralkaline rhyolites in the different tectonic settings is still a matter of debate and three hypotheses have been suggested: (a) crystal fractionation of alkali-basalt in a shallow reservoir to produce a trachyte which subsequently gives rise to a pantelle…
Chrząszcze w soli
2018
Kopalnia Soli „Wieliczka” jest obiektem sztucznie stworzonym przez człowieka, dawniej eksploatowanym, obecnie intensywnie odwiedzanym. Dzięki kopalni powstała nowa nisza ekologiczna, którą zaczęły zasiedlać troglofilne organizmy żywe. Jednymi z ciekawszych zwierząt żyjących w tej kopalni są chrząszcze Niptus hololeucus. Naturalnie występują w miejscach niezwiązanych z solnymi systemami podziemnymi, jednak zawleczone przystosowały się do troglobiontycznego trybu życia. Obecnie prowadzone badania ukierunkowane są m.in. na biologiczne i morfologiczne porównanie populacji troglofilnych z kopalni i żyjących poza nią. W tym celu przy pomocy pułapek Barbera pobierane są próby z 13 stanowisk z pozi…
Experimental Constraints on the Deep Magma Feeding System at StromboliVolcano, Italy
2009
International audience; New experiments have been performed on a high-K basalt (PST-9) from Stromboli volcano, Italy, to constrain the physical conditions of golden pumice magmas at their storage level and discuss their petrogenesis. Fluid-present, H2O- and CO2-bearing, near-liquidus experiments were performed at 11508C between 100 and 400MPa and under oxidizing conditions. Glasses were analyzed by Fourier transform IR spectroscopy and their H2O and CO2 concentrations compared with those in glass inclusions.Most glass inclusions cluster near the 200MPa isobar, suggesting entrapment at a depth of ~8 km. Golden pumice magmas have viscosities of 7.9 Pa s and densities of 2.48-2.57 g/cm3. Compo…
A model of degassing for Stromboli volcano
2010
International audience; A better understanding of degassing processes at open-vent basaltic volcanoes requires collection of new datasets of H2O–CO2–SO2 volcanic gas plume compositions, which acquisition has long been hampered by technical limitations. Here, we use the MultiGAS technique to provide the best-documented record of gas plume discharges from Stromboli volcano to date. We show that Stromboli's gases are dominated by H2O (48–98 mol%; mean, 80%), and by CO2 (2–50 mol%; mean, 17%) and SO2 (0.2–14 mol%; mean, 3%). The significant temporal variability in our dataset reflects the dynamic nature of degassing process during Strombolian activity; which we explore by interpreting our gas m…
Use-wear analysis applied in a dissected palimpsest at the Middle Palaeolithic site of El Salt (eastern Iberia): working with lithic tools in a narro…
2023
Los análisis de uso-desgaste son muy útiles para aumentar el conocimiento sobre las dinámicas económicas y de subsistencia llevadas a cabo por los neandertales. En términos generales, los resultados funcionales provienen tradicionalmente del análisis de herramientas pertenecientes a unidades estratigráficas cuya escala temporal se refiere al tiempo geológico. Esto se debe a que muchos yacimientos neandertales son palimpsestos de ocupaciones reiteradas a lo largo del tiempo, que deben ser diseccionadas para acercarnos a la escala temporal humana. En la unidad estratigráfica Xa de El Salt (Alcoi, este de Iberia) se han llevado a cabo estudios arqueoestratigráficos de alta resolución temporal.…