Search results for "layer"
showing 10 items of 2667 documents
Patterning of Magnetic Bimetallic Coordination Nanoparticles of Prussian Blue Derivatives by the Langmuir–Blodgett Technique
2012
We report a novel method to prepare patterns of nanoparticles over large areas of the substrate. This method is based on the adsorption of the negatively charged nanoparticles dispersed in an aqueous subphase onto a monolayer of the phospholipid dipalmitoyl-l-α-phosphatidylcholine (DPPC) at the air-water interface. It has been used to prepare patterns of nanoparticles of Prussian blue analogues (PBA) of different size (K(0.25)Ni[Fe(CN)(6)](0.75) (NiFe), K(0.25)Ni[Cr(CN)(6)](0.75) (NiCr), K(0.25)Ni[Co(CN)(6)](0.75) (NiCo), Cs(0.4)Co[Cr(CN)(6)](0.8) (CsCoCr), and Cs(0.4)Co[Fe(CN)(6)](0.9) (CsCoFe)). The behavior of DPPC monolayer at the air-water interface in the presence of the subphase of P…
Exchange coupling in an electrodeposited magnetic bilayer of Prussian blue analogues
2015
Bilayers of Prussian blue analogues (PBA) constituted of hard and soft magnets have been fabricated by means of electrochemical deposition. This method affords a good contact between two PBA thin films of nanometer thickness. Complete characterization of the resulting system has been performed, which has allowed the determination of the preservation of the chemical identity of both materials during the electrodeposition and the establishment of a clear interface between them. The magnetic behavior of the bilayer can be explained in terms of an exchange-spring magnet.
Self-assembly mechanism of nanoparticles of Ni-based Prussian Blue analogues at the air/liquid interface: a synchrotron X-ray reflectivity study.
2015
Prussian Blue analogue (PBA) nanoparticles can be self-assembled at air/liquid interfaces to build novel materials with interesting magnetic features. Herein, we study the influence of the size of PBA Cs0.4 Ni[Cr(CN)6 ]0.9 and K0.25 Ni[Fe(CN)6 ]0.75 nanoparticles on the self-assembly behavior by synchrotron X-ray reflectivity. Both nanoparticles show similar Z-potential values. The phospholipid dipalmitoylphosphatidylcholine and the amino surfactant dimethyldioctadecylammonium have been used as Langmuir monolayers to anchor the PBA nanoparticles and study the interplay of forces directing the self-assembly of the nanoparticles at the surfactant/liquid interface. Whereas Cs0.4 Ni[Cr(CN)6 ]0.…
Langmuir-Blodgett films based on Prussian Blue derivatives: Towards new hybrid magnetic materials
1999
Abstract The adsorption of dissolved Prussian Blue derivatives along a positively charged monolayer leads to new Langmuir-Blodgett (LB) films presenting a ferromagnetic state at low temperature. Such organic/inorganic systems containing inorganic sheets between organic amphiphilic layers constitute a new series of magnetic lamellar materials.
UV Index Experimental Values During the Years 2000 and 2001 from the Spanish Broadband UV-B Radiometric Network¶
2007
An analysis is made of experimental ultraviolet erythemal solar radiation data measured during the years 2000 and 2001 by the Spanish UV-B radiation evaluation and prediction network. This network consists of 16 Robertson-Berger type pyranometers for evaluating solar erythemal radiation and five Brewer spectroradiometers for evaluating the stratospheric ozone. On the basis of these data the Ultraviolet Index (UVI) was evaluated for the measuring stations that are located either in coastal regions or in the more densely populated regions inland on the Iberian Peninsula. It has been checked that in most cases the maximum irradiance values corresponded to solar noon, although there were except…
High quality nano-patterned thin films of the coordination compound {Fe(pyrazine)[Pt(CN)4]} deposited layer-by-layer
2011
International audience; An optimised procedure was developed for the layer-by-layer deposition of the Hofmann clathrate-like coordination compound {Fe(pyrazine)[Pt(CN)4]} either as continuous or as nano-patterned thin films. Characterization of the thickness and topography of the thin films by atomic force microscopy (AFM) and by surface plasmon resonance (SPR) spectroscopy, which also yields the layer's refractive index and losses, are reported. We found that the films are of good optical quality and the results of both AFM and SPR experiments are in good agreement with the theoretical predictions of the films thicknesses.
Zebrafish as a Model to Evaluate a CRISPR/Cas9-Based Exon Excision Approach as a Future Treatment Option for EYS-Associated Retinitis Pigmentosa
2021
Retinitis pigmentosa (RP) is an inherited retinal disease (IRD) with an overall prevalence of 1 in 4000 individuals. Mutations in EYS (Eyes shut homolog) are among the most frequent causes of non-syndromic autosomal recessively inherited RP and act via a loss-of-function mechanism. In light of the recent successes for other IRDs, we investigated the therapeutic potential of exon skipping for EYS-associated RP. CRISPR/Cas9 was employed to generate zebrafish from which the region encompassing the orthologous exons 37-41 of human EYS (eys exons 40-44) was excised from the genome. The excision of these exons was predicted to maintain the open reading frame and to result in the removal of exactl…
Development of a high performance thin layer chromatography method for the rapid qualification and quantification of phenolic compounds and abscisic …
2019
Honey is a natural product with a complex chemical composition consisting of sugars and other bioactive compounds. It is important in many traditional systems of medicine, exhibiting interesting bioactivities, in particular antimicrobial, anti-inflammatory and antioxidant effects. Authentication of botanical origin of honeys is particularly important in this context. Therefore, methods for quality control of honey and detection of its adulteration are very important. A HPTLC method for the quantitative determination of phenolic compounds in honey was developed for the first time. Seven phenolic compounds were detected and determined quantitatively in lime and acacia honey samples. The obtai…
Are analysts doing method validation in liquid chromatography?
2014
International audience; Method validation is being applied in the reported analytical methods for decades. Even before this protocol was defined, authors already somehow validated their methods without full awareness. They wished to assure the quality of their work. Validation is an applied approach to verify that a method is suitable and rugged enough to function as a quality control tool in different locations and times. The performance parameters and statistical protocols followed throughout a validation study vary with the source of guidelines. Before single laboratory validation, an analytical method should be fully developed and optimized. The purpose of the validation is to confirm p…
Analytical and Numerical Investigation of 3D Multilayer Detachment Folding
2013
Multilayer detachment folding, in which a sequence of sedimentary layers is compressed above a weaker salt layer, is a common mode of deformation in thin-skinned fold-and-thrust belts. Here, we investigate the dynamics of multilayer detachment folding with three different viscosities: lower detachment or salt layer, overlying weak layers and competent layers. A semi-analytical solution, based on thick plate analysis of multilayer systems, is used to create mechanical phase diagrams of folding dominant wavelength and growth rate as a function of material parameters. The validity of the phase diagrams is tested and confirmed beyond the nucleation stages of folding by performing several 2D and…