Search results for "absorptio"
showing 10 items of 2815 documents
Photochemical mineralization of terrigenous DOC to dissolved inorganic carbon in ocean
2018
When terrigenous dissolved organic carbon (tDOC) rich in chromophoric dissolved organic matter (tCDOM) enters the ocean, solar radiation mineralizes it partially into dissolved inorganic carbon (DIC). This study addresses the amount and the rates of DIC photoproduction from tDOC and the area of ocean required to photomineralize tDOC. We collected water samples from 10 major rivers, mixed them with artificial seawater, and irradiated them with simulated solar radiation to measure DIC photoproduction and the photobleaching of tCDOM. The linear relationship between DIC photoproduction and tCDOM photobleaching was used to estimate the amount of photoproduced DIC from the tCDOM fluxes of the stu…
Retrieval of canopy water content of different crop types with two new hyperspectral indices: Water Absorption Area Index and Depth Water Index
2018
Crop canopy water content (CWC) is an essential indicator of the crop’s physiological state. While a diverse range of vegetation indices have earlier been developed for the remote estimation of CWC, most of them are defined for specific crop types and areas, making them less universally applicable. We propose two new water content indices applicable to a wide variety of crop types, allowing to derive CWC maps at a large spatial scale. These indices were developed based on PROSAIL simulations and then optimized with an experimental dataset (SPARC03; Barrax, Spain). This dataset consists of water content and other biophysical variables for five common crop types (lucerne, corn, potato, sugar …
Ultrathin films of layered coordination polymers: charge transport and spin crossover at the nanoscale
2019
La present tesi doctoral ha estat realitzada com a compendi de publicacions i porta per títol "Pel·lícules ultrafines de polímers de coordinació en capes: transport de càrrega i transició d'espín en la nanoescala" (Ultrathin films of layered coordination polymers: charge transport and spin-crossover at the nanoscale). Aquesta es divideix en quatre capítols a més d'un capítol final de conclusions i resums en castellà i valencià. El primer capítol consisteix d'una introducció general enfocada cap a donar una visió general del transport de càrrega en xarxes metall-orgàniques (de l'anglès metal-organic frameworks, MOFs) i polímers de coordinació (de l'anglès coordination polymers, CPs), així co…
Glycerosomes: Use of hydrogenated soy phosphatidylcholine mixture and its effect on vesicle features and diclofenac skin penetration.
2016
In this work, diclofenac was encapsulated, as sodium salt, in glycerosomes containing 10, 20 or 30% of glycerol in the water phase with the aim to ameliorate its topical efficacy. Taking into account previous findings, glycerosome formulation was modified, in terms of economic suitability, using a cheap and commercially available mixture of hydrogenated soy phosphatidylcholine (P90H). P90H glycerosomes were spherical and multilamellar; photon correlation spectroscopy showed that obtained vesicles were ∼131nm, slightly larger and more polydispersed than those made with dipalmitoylphosphatidylcholine (DPPC) but, surprisingly, they were able to ameliorate the local delivery of diclofenac, whic…
COMBINATION OF ARGAN OIL AND PHOSPHOLIPIDS FOR THE DEVELOPMENT OF AN EFFECTIVE LIPOSOME-LIKE FORMULATION ABLE TO IMPROVE SKIN HYDRATION AND ALLANTOIN…
2016
Allantoin is traditionally employed in the treatment of skin ulcers and hypertrophic scars. In the present work, to improve its local deposition in the skin and deeper tissues, allantoin was incorporated in conventional liposomes and in new argan oil enriched liposomes. In both cases, obtained vesicles were unilamellar, as confirmed by cryo-TEM observation, but the addition of argan oil allowed a slight increase of the mean diameter (∼130nm versus ∼85nm). The formulations, especially those containing argan oil, favoured the allantoin accumulation in the skin, in particular in the dermis (∼8.7μg/cm(2)), and its permeation through the skin (∼33μg/cm(2)). The performances of vesicles as skin d…
Nanodesign of new self-assembling core-shell gellan-transfersomes loading baicalin and in vivo evaluation of repair response in skin
2017
Gellan nanohydrogel and phospholipid vesicles were combined to incorporate baicalin in new self-assembling core-shell gellan-transfersomes obtained by an easy, scalable method. The vesicles were small in size (~107 nm) and monodispersed (P.I. ≤ 0.24), forming a viscous system (~24 mPa/s) as compared to transfersomes (~1.6 mPa/s), as confirmed by rheological studies. Gellan was anchored to the bilayer domains through cholesterol, and the polymer chains were distributed onto the outer surface of the bilayer, thus forming a core-shell structure, as suggested by SAXS analyses. The optimal carrier ability of core-shell gellan-transfersomes was established by the high deposition of baicalin in th…
A dual channel sulphur-containing a macrocycle functionalised BODIPY probe for the detection of Hg(II) in a mixed aqueous solution
2018
We report herein the synthesis and chromo-fluorogenic behaviour of a new probe 1 containing a boron-dipirromethene (BODIPY) unit electronically connected with a dithia-dioxa-aza macrocycle. Acetonitrile and water-acetonitrile 95:5 v/v solutions of the probe showed an ICT band in the visible zone and are nearly non-emissive. When acetonitrile was used as solvent, addition of Hg(II) and trivalent metal cations induced an hypsochromic shift of the absorption band and moderate emission enhancements. A highly selective response was obtained when using competitive media such as wateracetonitrile 95:5 v/v. In this case only Hg(II) induced a hypsochromic shift of the absorption band and a marked em…
Negative thermal expansion in cuprite-type compounds: A combined synchrotron XRPD, EXAFS, and computational study of Cu2O and Ag2O
2006
Cuprite-type oxides (Cu2O and Ag2O) are framework structures composed by two interpenetrated networks of metal-sharing M4O tetrahedra (M = Cu, Ag). Both compounds exhibit a peculiar negative thermal expansion (NTE) behaviour over an extended temperature range (9 240 K for Cu2O, 30-470 K for Ag2O). High-accuracy synchrotron powder diffraction and EXAFS measurements were performed from 10 K up to the decomposition temperature to understand the nature of the NTE effects. The critical comparison of the diffraction and absorption results concerning the temperature dependence of the interatomic distances and of the atomic vibrational parameters proves to be fundamental in defining the local dynam…
Multiple scattering approach for two-electron resonant emission studied by angle-resolved coincidence spectroscopy.
2008
International audience; We have developed a generalization of the multiple-scattering formalism to deal with Auger-photoelectron coincidence spectroscopy APECS in the solid state. We have merged the exact atomic treatment of the angular correlations between the two electrons and the single-particle approach, on which the multiplescattering description of condensed matter relies. This allows the recovering, even in extended systems, of the entangled form of the electron-pair wave function characterizing the coincidence angular diffraction pattern. In the atomic limit our formalism correctly reproduces the cross section, as calculated within the statistical-tensors approach, usually employed …
Decorated pottery study: Analysis of pigments by x-ray absorbance spectroscopy measurements
2007
Characterization of pigments on decorated pottery fragments has been fully carried out by nondestructive x-ray absorbance spectroscopy (XAS). The samples were a series of pottery shards excavated from the archeological site of Caltagirone (Sicily, Italy), a well-known ceramic production center. Aesthetical criteria and morphological observations allowed us to attribute the samples to quite different historical periods, starting from the 18th century B.C. up to the 16th century A.D. An extensive time interval led us to suppose that different materials and techniques were used for the production of the ceramic paste and also for the preparation of pigments. XAS measurements were performed at …