Ion migration study in acid-leached soda–lime–silica glass by thermally stimulated depolarization current analysis

Ionic conductivity in silicate glasses is a major issue in the energy sector due to its detrimental effect on electric energy generation and storage and has received increasing attention over the past years. In this study, surface modification of soda–lime–silica (SLS) float glass via acid-leaching treatment (pH 1) was implemented to understand the impact on ionic transport. The acid-leaching treatment created a sodium-depleted “silica-like” structure in the near-surface region with depths of 110 ± 20 nm for the air-side and 93 ± 2 nm for the tin-side of the SLS glass. Using the thermally stimulated depolarization current technique, two thermally activated relaxation peaks were found to be associated with different ion migration mechanisms. The first peak (P1) with activation energy of ∼0.85 eV was attributed to dc conduction of Na⁺ ions through the glass bulk. A second overlapping peak (P2) at a higher temperature was found to be related to a more limited Na⁺ ion migration through the acid-leached structure, due to H⁺ conduction, or a coupled contribution of both mechanisms.     

Fatty Acid Profiles of Virgin Olive Oils from the Five Olive-Growing Zones of Extremadura (Spain)

In this study, 278 samples of virgin olive oil from 40 mills belonging to five olive-growing zones of Extremadura were evaluated according to their fatty acid composition. An analysis of variance of the fatty acid contents, and their principal group subtotals and ratios revealed significant differences at the 95 % confidence level between zones. Means were compared using Tukey’s HSD test (p < 0.05). A discriminant analysis, taking the zone as the grouping variable and the different fatty acids and their ratios as independent variables, explained nearly 90 % of the variance with the first two functions. The model correctly classified 88.8 % of the analysed samples into their proper olive-growing zone. Validation against an extra test set of 30 samples resulted in 90 % being correctly classified; the results of the discriminant analysis were therefore considered to be validated. A two-dimensional graphical representation of the different groups studied using the first two resulting canonical discriminant functions clearly showed the Sierra Norte of Cáceres and Vegas del Guadiana each to be clearly separated from the rest and from each other, while the other three zones—Siberia, Serena and Tierra de Barros—overlapped considerably.     

Effective Elimination and Biodegradation of Polycyclic Aromatic Hydrocarbons from Seawater through the Formation of Magnetic Microfibres

Supramolecular aggregates formed between polycyclic aromatic hydrocarbons and either naphthalene or perylene-derived diimides have been anchored in magnetite magnetic nanoparticles. The high affinity and stability of these aggregates allow them to capture and confine these extremely carcinogenic contaminants in a reduced space. In some cases, the high cohesion of these aggregates leads to the formation of magnetic microfibres of several microns in length, which can be isolated from the solution by the direct action of a magnet. Here we show a practical application of bioremediation aimed at the environmental decontamination of naphthalene, a very profuse contaminant, based on the uptake, sequestration, and acceleration of the biodegradation of the formed supramolecular aggregate, by the direct action of a bacterium of the lineage Roseobacter (biocompatible with nanostructured receptors and very widespread in marine environments) without providing more toxicity to the environment.     

Improved Suzuki–Miyaura reaction conversion efficiency using magnetic nanoparticles and inductive heating

Journal of Materials Science - The use of magnetic nanoparticles in C–C coupling reactions enables the facile recovery of the catalyst under environmentally friendly conditions. Herein, the...     

Sensor‐response‐ratio constancy under changes in natural and artificial illuminants

We have analyzed the constancy of the response ratio for cones, second‐stage mechanisms, and CCD sensors when daylight or an artificial illuminant (A, F2, F7, and F11) is changed to an equal‐energy illuminant (E) in scenes containing natural and artificial objects. The response ratios were always found to be roughly constant for all the sensors. For daylight, we have deduced mathematical expressions, which relate the values of these ratios with the correlated color temperature (CCT) and applied these expressions to the synthesis of images of a scene viewed under different daylights corresponding to a variety of CCTs. The results were highly satisfactory in a rural scene for any CCT. In the scene with artificial objects, the results were also good for nonextreme CCTs. We also included in our study artificial illuminants, with which we achieved very good image syntheses for illuminants A and F7. © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 284–292, 2007     

Kinetic study of the synthesis of n-octyl octanoate using cobalt chloride as catalyst

The kinetics of the pseudohomogeneous liquid phase synthesis of a high molecular weight ester in a stirred tank reactor using cobalt chloride as catalyst has been studied at various temperatures, catalyst concentrations, and acid/alcohol molar ratios. A kinetic model has been determined that predicts the experimental results quite well.     

High-dose glucocorticoids in multiple sclerosis patients exert direct effects on the kidney and skeleton

Radical nephrectomy was performed in 30 cases of renal cell carcinoma in which CT scan and angiography findings had indicated the possible suitability of enucleation. The lesions were then enucleated from the operative specimens and assessed histologically to find the feasibility of tumor enucleation and to determine its indications. Histological investigation demonstrated that the tumor was completely surrounded by the pseudocapsule in only 17 cases, and even in such tumors the thickness of the pseudocapsule was not always regular and sometimes tumor invasion was seen in the pseudocapsule. It is therefore advisable to resect the tumor with no less than several mm of surrounding renal tissue when the pseudocapsule can not be clearly distinguished. Success of the enucleation was confirmed histologically in 22 out of 30 cases (73.3%). The factors related to failure of the enucleation were invasion throughout the renal capsule in 2, tumor exposure on the resected surface in 5, residual tumor in the tumor bed in 2 and venous invasion in 6 cases. Satellite tumors were not detected in any case. Favorable results were obtained in low grade, low stage tumors less than 6 cm in diameter and clearly distinct from normal renal tissue, therefore such cases were thought to be appropriate indications for enucleation. Although we selected the cases thought to be appropriate for enucleation by imaging techniques preoperatively, success was not obtained in all cases. Enucleation is a useful and recommendable operative technique for bilateral renal cell carcinoma or renal cell carcinoma in a solitary kidney.(ABSTRACT TRUNCATED AT 250 WORDS)