Search results for "physicochemical"
showing 10 items of 67 documents
Thermomineral waters of Greece: geochemical characterization
2020
Physicochemical characterization of passive films on niobium by admittance and electrochemical impedance spectroscopy studies
2005
An analysis of the electronic properties of amorphous semiconductor-electrolyte junction is reported for thin (D ox < 20 nm) passive film grown on Nb in acidic electrolyte. It will be shown that the theory of amorphous semiconductor-electrolyte junction (a-SC/EI) both in the low band-bending and high band-bending regime is able to explain the admittance data of a-Nb 2 O 5 /El interface in a large range (10 Hz-10 kHz) of frequency and electrode potential values. A modelling of experimental EIS data at different potentials and in the frequency range of 0.1 Hz-100 kHz is presented based on the theory of amorphous semiconductor and compared with the results of the fitting of the admittance data…
Synergism between exposure to mercury and use of iodine supplements on thyroid hormones in pregnant women
2015
Objective: To evaluate the association between mercury exposure and thyroid-stimulating hormone (TSH), total triiodothyronine (TT3) and free thyroxine (FT4) levels during pregnancy as well as to explore if there is any synergic action between mercury and intake of iodine from different sources. Methods: The study population was 1407 pregnant women participating in the Spanish INMA birth cohort study. Total mercury concentrations were analyzed in cord blood. Thyroid hormones (THs) were measured in serum samples collected at 13.2 +/- 1.5 weeks of gestation. The association between mercury and TH levels was evaluated with multivariate linear regression models. Effect modification caused by iod…
Nuevos datos sobre el uso de materia colorante durante el Neolítico antiguo en las comarcas centrales valencianas
2006
La caracterización mineralógica de materias colorantes procedentes de los yacimientos valencianos de la Cova de l'Or, la Cova de la Sarna y la Cova Fosca de la Vall d'Ebo demuestra el uso de dos tipos de materia colorante durante el Neolítico Antiguo: Hematites y Cinabrio. Las características y distribución geográfica de cada una de ellas nos remiten a dos estrategias distintas de obtención y. probablemente. de utilización de las mismas.
Water-Soluble Polysaccharides from Ephedra alata Stems: Structural Characterization, Functional Properties, and Antioxidant Activity
2020
In this study, the physicochemical characterization, functional properties, and antioxidant activity of polysaccharides extracted from Ephedra alata (EAP) were investigated. EAP were extracted in water during 3 h with a liquid/solid ratio of 5 in a water bath at 90 °
Flos Tectorii degradation of mortars: An example of synergistic action between soluble salts and biodeteriogens
2015
Abstract The definition of Flos Tectorii, originally suggested by F.S. Brancato in the 1980s’ (Brancato, 1986), refers to a unique form of deterioration identified on both aerial and hydraulic mortars used in the external walls of historic and contemporary buildings. It is clearly recognizable due to the development of peculiar concentric (occasionally sub-circular) macroscopic forms. At present, there is still a lack of information about the full interpretation of this phenomenon regarding the interaction between the different physicochemical and biological factors that lead to this particular type of degradation. The present study was aimed to examine whether the specific mineralogical an…
Halloysite-Based Bionanocomposites
2017
Scientific research has been invigorated by a new class of biodegradable materials as alternatives to polymers derived from fossils. Such biomaterials can also offer economic advantages because they are derived from renewable resources. Several biopolymers (gelatin, chitin, chitosan, starch, pectin, cellulose and its modified versions, etc.) have been exploited to produce films and formulations. Their use is limited because of fast degradation, predominant hydrophilic character, and, in some cases, unsatisfactory mechanical properties. However, the properties of these polymers can be improved by using inorganic fillers such as additives. Halloysite nanotube is a promising green filler for t…
Obesity interferes with the orosensory detection of long-chain fatty acids in humans
2014
Background: The association between the orosensory detection of lipids, preference for fatty foods, and body mass index (BMI; in kg/m 2 ) is controversial in humans. Objective: We explored the oral lipid-sensing system and the orosensory-induced autonomic reflex system in lean and obese subjects. Design: Lean (BMI: 19 to ,25; n = 30) and obese (BMI .30; n = 29) age-matched men were enrolled. Their oral threshold sensitivity to linoleic acid (LA) was determined by using a 3-alternative forced-choice ascending procedure, and their eating habits were established by the analysis of 4 consecutive 24-h food-consumption diaries. The effect of brief oral lipid stimulations on plasma triglyceride [(…
Pulsed electric fields as an alternative to thermal processing for preservation of nutritive and physicochemical properties of beverages: A review
2017
Fruit juices and other beverages constitute an important source of bioactive compounds, but thermal processing may reduce their contents thus decreasing natural nutritive value of foods. This has been recently led to the use of non-thermal technologies, especially pulsed electric fields (PEF) as an interesting alternative to thermal pasteurization of beverages. Reported results show that PEF is a useful for pasteurization of fruit juices that can minimize changes in physicochemical and nutritional properties with retention of higher amounts of health-related phytochemicals. This study presents an overview of the effect of PEF on the physicochemical (e.g., Brix, pH, viscosity, acidity, color…
When the functionalisation comes in useful: ionic liquids with a “sweet” appended moiety demonstrate drastically reduced toxicological effects
2020
The growing number of applications of ionic liquids (ILs) in industry have brought attention to the green credentials of synthesis, as well as their cytotoxicities and ecotoxicities both for their use and accidental leakage into the environment. With the abovementioned properties in mind, we designed a class of ILs with either cations bearing a gluconamide motif and aliphatic side chains or the anion incorporating a gluconic acid (derived from food waste) moiety. An IL with an imidazolium cation with an appended gluconic amide (bearing five hydroxyl groups) moiety was also synthesized for a useful comparison. Different structural features were considered, placing emphasis on the nature and …