Inertial Krasnoselskii-Mann Iterations

We establish the weak convergence of inertial Krasnoselskii-Mann iterations towards a common fixed point of a family of quasi-nonexpansive operators, along with worst case estimates for the rate at which the residuals vanish. Strong and linear convergence are obtained in the quasi-contractive setting. In both cases, we highlight the relationship with the non-inertial case, and show that passing from one regime to the other is a continuous process in terms of parameter hypotheses and convergence rates. Numerical illustrations for an inertial primaldual method and an inertial three-operator splitting algorithm, whose performance is superior to that of their non-inertial counterparts

The fossil rodent faunas of the localities Alcoy 2C and 2D (Alcoy Basin, Spain). Implications for dating the classical locality of Alcoy-Mina

In the Gormaig area (Alcoy basin, SE Spain) a number of fossil mammal localities are known, of which only the classic site of Alcoy-Mina, known since the mid-19th century, has yielded remains of macrofauna. In the vicinity of this site are the localities of Alcoy-2C (AL2C) and Alcoy-2D (AL2D), probably representing the levels of Alcoy-Mina. The faunal assemblage allows dating the AL2C and AL2D localities as Early Pliocene (end of the Early Ruscinian or early-late Ruscinian boundary, MN14-MN15). Several taxa (Pliopetaurista and Glis) are thought to have affinities for humid and close biotopes. En el área del Gormaig (cuenca de Alcoy, SE España), se conocen toda una serie de yacimientos de mamíferos fósiles, de los cuales tan sólo la localidad clásica de Alcoy-Mina, conocida desde mediados del siglo XIX, ha aportado restos de macrofauna. En las proximidades de esta localidad se encuentran los yacimientos de Alcoy-2C (AL2C) y Alcoy-2D (AL2D), probablemente representando los niveles fosilíferos de Alcoy-Mina. La asociación faunística encontrada en AL2C y AL2D permite la datación de estas localidades como pertenecientes al Plioceno inferior (fin del Rusciniense inferior o límite Rusciniense inferior-superior, zona MN14-MN15). Varios taxones (Pliopetaurista y Glis) se consideran indicadores de biotopos cerrados de carácter húmedo

Crotonaldehyde hydrogenation on Rh/TiO2 catalysts. In situ DRIFTS studies

The surface and catalytic properties in the vapor-phase hydrogenation of crotonaldehyde on Rh/TiO2 has been studied. It was found that a partial reduction of the support produces a surface decoration of the metal component. Thus, interfacial sites are created, which are responsible of an increase in the selectivity to crotyl alcohol, via enhancement of the polarization of the C=O bond. Photoelectron spectra revelead that rhodium is in different oxidation states, with a contribution of ca. 20 % Rhd + and 80 % Rhº species for LTR catalyst and only a slight increase of Rhd + for HTR catalyst. TEM studies revelead that Rh has metal particle size close 3 nm with small increases in the catalyst reduced at high temperature. DRIFTS essayed carried out under reaction conditions allowed to identify crotonaldehyde species strongly adsorbed through the C=C bond and weakly coordinated through both the C=C and C=O bonds. After reduction at 723 K an increase in the peak at 1660 cm-1 ascribed to an interaction between the carbonyl group and the surface, was observed. This peak seems to be stabilized at interfacial Rh/TiOx sites The deactivation in crotyl alcohol formation can be ascribed to the generation of strongly chemisorbed asymmetric carboxylate species detected by band at 1740 cm-1. This band grows at expense of crotonaldehyde O s - bonded intermediate chemisorbed on coordinatively unsaturated sites (Lewis acid sites) responsible of the crotyl alcohol obtaintion (detected by a band at 1653 cm-1). Additionally, a small band at 2068 cm-1 assigned to CO adsorbed on transition metals, which increases with time on-stream may explain the deactivation of the catalysts in flow systems

Improved O2-assisted styrene synthesis by double-function purification of SWCNT catalyst

The catalytic performance of SWCNT was notably improved in the oxidative dehydrogenation of ethylbenzene (EB) to styrene (ST) upon a double-function purification in one step of the raw SWCNT. This consists of lowering the MeOx concentration and generating surface C=O groups after processing it in nitric acid at controlled conditions, while preserving the structure. The textural improvement was ascribed to the cutting of the tubes/bundles by oxidation and to MeOx removal itself (dilution effect). Both EB conversion and ST selectivity increased with a parallel lowering of the undesired COx selectivity. The conversion was interpreted by the enhancement of the intrinsic properties (i.e., more surface ketonic groups) but also to the higher load of SWCNT in the bed upon purification; both factors contribute to a higher number of active sites (C=O) in the bed for styrene formation. The most purified catalyst underperformed in conversion once the purification altered the SWCNT structure notably. Thus, preserving the structure is an important condition to achieve high conversion and yield. The better selectivity was explained in two ways; more styrene-forming sites (C=O) or less COx-forming sites (uncoated MeOx) in the bed, or both. The styrene yield per catalyst volume was improved by an average of ca. 240 % in comparison to the non-purified SWCNT. Deactivation is critical in maximizing the purification effect on the intrinsic and volumetric yields. In practical terms, the purification method proved to enhance the reaction; the selectivity towards the unwanted COx was significantly lowered with a gain towards styrene, achieving comparable selectivity values as in the conventional process, but operated at much lower temperature

Household Appliances Identification : Hands-on integrative workshop and its adaptation to a social distancing context.

Theoretical and practical knowledge integration is essential in Electrical Engineering. Throughout the degree, students must tackle specific problems where they can put into practice difficult concepts and test their learning. Taking this into consideration, an integrative workshop is implemented in the third year that seeks to strengthen skills such as: analysis and design of signal conditioning circuits, designing and printing circuits, signal acquisition and processing, pattern recognition and classification, integration of a system. The workshop is based on the topic of load identification which is a challenging problem, suitable for developing multiple electrical engineering concepts and also an interesting subject for the initiation of the students to research. This article shares the 2019 edition experience and its adaptation to non-classroom classes in 2020 in the context of social distancing restrictions due the coronavirus disease. The 2019 didactic proposal and the necessary modifications for 2020 are presented and analyzed. Although loosing the fruitful interaction between teachers and students in the lab in 2020, most of the hands-on activities could be maintained helped by the use of USB oscilloscopes/analyzers that give students the functionality of a lab at home. It is concluded that both editions, in spite of their different teaching modalities, achieved good academic results

New data on the turtles from Puerto de la Cadena (Late Miocene of Murcia)

La Alberca es un yacimiento paleontológico del Mioceno Superior situado en el área del Puerto de la Cadena (Murcia, España). Allí se ha identificado una fauna de mamíferos relativamente diversa. No obstante, la información referente a sus tortugas era, hasta ahora, muy limitada. En otros yacimientos del Puerto de la cadena se han identificado abundantes restos de tortugas, asignados a Testudinidae. El estudio de las tortugas de La Alberca permite identificar un miembro de Testudinidae de gran tamaño, asignado preliminarmente a Cheirogaster cf. bolivari, y una tortuga acuática, assignada a Trionychinae. Este último hallazgo aumenta el rango de distribución estratigráfica de este grupo de quelonios en la Península Ibérica. Además, constituye la primera referencia a Trionychinae en la mitad sur de España. La revisión de material inédito permite identificar la presencia de Trionychinae en otros afloramientos del Puerto de la CadenaLa Alberca is a fossil site of the Late Miocene of the area of Puerto de la Cadena (Murcia, Spain). A mammalian fauna with relatively high diversity has been identified there. However, the information about the turtles was, until now, very limited. Abundant turtles, assigned to Testudinidae, have been recognized in other sites of Puerto de la Cadena. The study of the turtles from La Alberca allows to identify a large taxon of testudinid turtle, assigned to Cheirogaster cf. bolivari, and a aquatic turtle, assigned to Trionychinae. This finding broadens the stratigraphic distribution of the group in the Iberian Peninsula. In addition, it constitutes the first reference to Trionychinae in the southern half of Spain. The review of unpublished material allows to identify Trionychinae in other sites of Puerto de la Caden

HPLC Method for Quantification of Oxidative Stress by Salicilate Hydroxylation in Human Plasma

The aim of the present study was to modify and validate a high-performance liquid chromatographic (HPLC) method for determining 2,3 and 2,5 dihydroxybenzoic acid (2,3-DHBA and 2,5-DHBA) from salicylic acid in human plasma. The mobile phase was a mixture of sodium acetate/citrate (pH 2.5) 30 mM-methanol (93:7, v/v). The injection volume was 10 µL. Retention time for 2,5- DHBA, and 2,3-DHBA was 4.5 ± 0.10 and 5.8 ± 0.15 min, respectively. The detection and quantification limits were 10 and 40 nM for 2,3-DHBA and 8 and 20 nM for 2,5-DHBA. Linearity was evaluated in the range of 40–1600 nM for both metabolites. Inter-and intra-analysis variation coefficient was below 10%. Good recoveries of more than 99% were obtained for both metabolites using this method

Effect of lanthanum on the catalytic properties of PtSn/γ-Al2O3 bimetallic catalysts prepared by successive impregnation and controlled surface reaction.

Bimetallic PtSn/γ -Al2O3–La2O3 catalysts were prepared by two comparative methods, successive impregnation (SI) and controlled surface reaction (CSR). FTIR-pyridine adsorption revealed a decrease in support acidity as a function of lanthanum content. Oxidized Pt2+ was identified by CO-FTIR chemisorption and by XPS spectra on catalysts prepared by SI. When the CSR preparation method was used, reduced Pt0 was observed and oxidized Pt2+ was not detected. As the lanthanum content increased a diminution in cyclohexane dehydrogenation and n-heptane conversion was observed. Low hydrogenolysis and high selectivity to C7-olefins were obtained in both preparations. It is proposed that lanthanum in SI catalysts stabilizes the platinum in an oxidation state, Pt2+, and diminishes the support acidity. In CSR preparations the lanthanum effect is limited to inhibit the support acidity and hence to the bifunctional reactions occurring during the n-heptane conversion

Aplicación de recursos de investigación en la docencia: Técnicas de microscopía en Geociencias

Se presentan los resultados más significativos del proyecto de innovación docente enmarcado dentro de las redes de innovación docente de la Universidad de Alicante. En este trabajo se han examinado una serie de técnicas para la adquisición de microfotografías de utilidad en Geociencias. En particular, los materiales estudiados incluyen microfósiles marinos (foraminíferos) y sedimentos arenosos. Las técnicas analizadas abarcan los siguientes dispositivos: a) microscopio electrónico de barrido; b) microscopio trilocular con iluminación led de luz fría – cámara réflex; y c) estereomicroscopio (lupa binocular) – cámara IDS. El análisis de las distintas fotografías obtenidas ha permitido establecer las mejores condiciones e instrumental para aplicar estas técnicas como recurso de investigación aplicado a la didáctica de las geociencias