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991.
Caroline Desfours Sylvie Calas-Etienne Robert Horvath Marta Martin Csilla Gergely Frédéric Cuisinier Pascal Etienne 《Applied Physics A: Materials Science & Processing》2014,114(2):435-443
The aim of this work is to demonstrate the sensing ability of reverse-symmetry waveguides to investigate adsorption of casein and build-up of poly-L-lysine mediated casein multilayers. A first part of this study is dedicated to the elaboration and characterization of ultra-porous thin films with very low refractive indices by an appropriate sol–gel method. This will form the basis of our planar optical sensors. Optical waveguide light mode spectroscopy is a real-time and sensitive method to study protein adsorption kinetics and lipid bilayers. We used it to test the obtained waveguides for in-situ monitoring of biomolecule adsorption. As a result, significant changes in the incoupling peak position were observed during the layer-by-layer adsorption. Finally, refractive index and thickness of the adsorbed layers were established. 相似文献
992.
Grochowicz Marta Pączkowski Przemysław Gawdzik Barbara 《Journal of Thermal Analysis and Calorimetry》2018,133(1):499-508
Journal of Thermal Analysis and Calorimetry - The study describes the thermal properties of functional microspheres composed of glycidyl methacrylate (GMA) and crosslinking agent ethylene glycol... 相似文献
993.
Marta Letizia Antonelli Camillo La Mesa Rosalia Fortunata Tornelli Caterina Letizia 《Thermochimica Acta》2007,456(1):13-18
Negatively charged vesicles made of non-stoichiometric amounts of sodium dodecylsulfate and cetyltrimethylammonium bromide were characterised by physico-chemical methods. Interactions with lysozyme were examined by calorimetry. A remarkable heat effect is observed upon diluting the protein with the vesicular pseudo-solvent. The maximum ΔHbind value occurs at complete vesicle charge neutralisation by the protein. 相似文献
994.
995.
The paper reports a new, nonconventional method for the preparation of oxygen-containing niobium compounds, based upon coprecipitation. The coprecipitation product of niobic acid with lead oxalate was used as precursor. Lead metaniobate was obtained by proper thermal treatment of the coprecipitate. The coprecipitate mechanism was studied and the optimal conditions for quantitative precipitation of niobium and lead were established. The mechanism of thermal decomposition of the coprecipitate was investigated by differential thermal analysis and X-ray powder diagrams. The final product of thermal decomposition, lead metaniobate, is formed at 850°C. 相似文献
996.
Marta B Ferraro Viviana Repetto Julio C Facelli 《Solid state nuclear magnetic resonance》1998,10(4):185-189
This paper presents results from applying different point charge models to take into account intermolecular interactions to model the solid state effects on the 15N NMR chemical shifts tensors. The DFT approach with the BLYP gradient corrected exchange correlation functional has been used because it can include electron correlation effects at a reasonable cost and is able to reproduce 15N NMR chemical shifts with reasonable accuracy. The results obtained with the point charge models are compared with the experimental data and with results obtained using the cluster model, which includes explicitly neighboring molecular fragments. The results show that the point charge models can take into account solid state effects at a cost much lower than the cluster methods. 相似文献
997.
Vlastimil Matejec Miloš Hayer Peter Pavlovič Marta Kubečková Gabriela Kuncová Massimo Guglielmi 《Journal of Sol-Gel Science and Technology》1995,5(3):193-199
SiO2, TiO2, ZrO2, and TiO2-ZrO2 thin coatings were applied by sol-gel method on quartz fibres during the fibre drawing. Durable layers with the thicknesses up to 0.7 m were obtained. The layer smoothness and thickness were determined using electron microprobe analyzer and electron or optical microscopy. In order to investigate a decrease in the strength of sol-gel coated fibres a novel method employing silica capillaries was developed. The fibre strength decrease was explained by the influence of water penetrating as a result of the coating process into the flaws on the fibre surface. 相似文献
998.
Rossetti FF Bally M Michel R Textor M Reviakine I 《Langmuir : the ACS journal of surfaces and colloids》2005,21(14):6443-6450
Titanium is widely used in biomedical applications. Its mechanical properties and biocompatibility, conferred by a layer of oxide present on its surface, make titanium the material of choice for various implants (artificial hip and knee joints, dental prosthetics, vascular stents, heart valves). Furthermore, the high refractive index of titanium oxide is advantageous in biosensor applications based on optical detection methods. In both of the above fields of application, novel surface modification strategies leading to biointeractive interfaces (that trigger specific responses in biological systems) are continuously sought. In this report, we investigate the interactions between TiO2 and phosphatidyl serine-containing liposomes, present a novel approach for preparing supported phospholipid bilayers (SPBs) of various compositions on TiO2, and use the unique ability of liposomes to distinguish between different surfaces to create SPB corrals on SiO2/TiO2 structured substrates. These results represent an important first step toward the design of biointeractive interfaces on titanium oxide surfaces that are based on a cell membrane-like environment. 相似文献
999.
An ion-pair liquid chromatographic assay was developed and validated for the determination of ceftriaxone in cerebrospinal fluid. Chromatographic separation was achieved on a C18 column (125 x 4 mm, 5 microm) with detection at 270 nm, a 1 mL/min flow rate and a 50 microL loop. The mobile phase consisted of 300 mL acetonitrile, 50 mL 0.1M phosphate buffer (pH 7.4), 3.2 g tetrabutylammonium bromide as the ion-pairing agent, and dilution with distilled deionized water to 1 L. Cephradine was used as the internal standard. The assay was linear for ceftriaxone concentrations of 0.5-50 microg/mL. The coefficients of variation for precision were <4.61%. The accuracy ranged from 96.07 to 102.42%. The detection and quantitation limits were 0.019 and 0.065 microg/mL, respectively. This method was used to quantify ceftriaxone in the cerebrospinal fluid of children with meningitis. The results showed that the method described here is useful for the determination of ceftriaxone in cerebrospinal fluid. 相似文献
1000.
Yi -Ming Liu Maria Rosario Fernández de la Campa Marta Elena Díaz García Alfredo Sanz-Medel 《Mikrochimica acta》1991,103(1-2):53-64
The Ga(III)-7-iodo-8-hydroxyquinoline-5-sulfonic acid complex in the presence of suitable micelles and with sodium sulfite as oxygen scavenger exhibited strong phosphorescence at room temperature in aqueous solutions. This micellar reaction provides the basis for a convenient phosphorimetric determination of traces of gallium. Different types of micelles showed their maximum enhancing effects at different pH ranges, affording greater convenience for various analytical purposes. A phosphorimetric procedure with surfactant cetyltrimethylammonium bromide as enhancing agent is proposed. The detection limit for gallium was 5 ng/ml and the calibration graph was rectilinear in the range of 5 to 600 ng/ml. The relative standard deviation was 4% at 50 ng/ml level. The applicability of this room-temperature phosphorimetric procedure to multi-component analyses for the group III elements, Al(III), Ga(III), and In(III), was demonstrated. Kalman filtering was used to deconvolute the phosphorescence spectra of mixtures of aluminium and gallium allowing the simultaneous determination of both metals with satisfactory results. 相似文献