964 resultados para Ferdinand VII, King of Spain, 1784-1833.


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Simulated cold-start tests have been carried out to evaluate the performance of H-ZSM-5 and H-BETA zeolites as hydrocarbon traps under simulated gasoline car exhaust gases, paying special attention to the effect of water on their behaviour. It is concluded that the hydrothermal treatment of the zeolites in the acidic form contributes to the better performance of these materials as hydrocarbon traps since the stabilization of the zeolites takes place. Moreover, the decrease of the surface acidity of the zeolites results in an increase of the Si/Al ratio, which contributes to the decrease of the water affinity for adsorption sites. Thus, the competition with hydrocarbon molecules in the exhaust for the adsorption sites is reduced which increases their trap efficiency. The stabilized H-ZSM-5 is the zeolite that showed the best performance with a propene offset temperature of 240 °C, which should be high enough for the three-way catalyst to carry out its role as catalytic converter.

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The aim of this study is to investigate the effect of particle size on the non-isothermal pyrolysis of almond shells (AS) and olive stones (OS) and to show possible differences in the composition of the different fractions obtained after milling and sieving. The results obtained from the study of different particle size of AS and OS samples show significant differences in the solid residue obtained and in the shape and overlapping degree of the peaks, especially with the smaller particle size. These differences can be due to different factors: (a) the amount of inorganic matter, which increases as particle size decreases, (b) heat and mass transfer processes, (c) different sample composition as a consequence of the milling process which may provoke changes in the structure and the segregation of the components (in addition to the ashes) increasingly changes the composition of the sample as the particle size decreases.

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Purpose: The aim of the present study was to describe sexual health in Spain according to three important indicators of the World Health Organization definition and explore the influence of socioeconomic factors. Methods: We performed a population-based cross-sectional study of sexually active people aged 16-44 years residing in Spain in 2009 (2365 women and 2532 men). Three main aspects of sexual health were explored: sexual satisfaction, safe sex, and sexual abuse. The independent variables explored were age, age at first intercourse, reason for first intercourse, type of partner, level of education, country of origin, religiousness, parity, and social class. Bivariate and multivariate logistic regression models were fitted. Results: Both men and women were quite satisfied with their sexual life, their first sexual intercourse, and their sexual relationships during the previous year. Most participants had practiced safe sex both at first intercourse and during the previous year. Levels of sexual abuse were similar to those in other developed countries. People of disadvantaged socioeconomic position have less satisfying, more unsafe, and more abusive sexual relationships. Women experienced more sexual abuse and had less satisfaction at their first intercourse. Conclusions: The state of sexual health in Spain is relatively good. However, we observed inequalities according to gender and socioeconomic position.

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The multiobjective optimization model studied in this paper deals with simultaneous minimization of finitely many linear functions subject to an arbitrary number of uncertain linear constraints. We first provide a radius of robust feasibility guaranteeing the feasibility of the robust counterpart under affine data parametrization. We then establish dual characterizations of robust solutions of our model that are immunized against data uncertainty by way of characterizing corresponding solutions of robust counterpart of the model. Consequently, we present robust duality theorems relating the value of the robust model with the corresponding value of its dual problem.

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Purpose: This paper aims to propose models that capture the own effect of price promotions of virtue and vice products on sales and cross effects within the subcategory, between subcategories and between periods. The hypotheses assume that, due to reverse consumption self-control, the demand for vice products is more price-sensitive than demand for virtue products, but the demand for vice products is less price-sensitive between periods than demand for virtue products; furthermore, due to the degree of impulse-buying and to licensing, the demand sensitivity of the products of a subcategory and of those of other subcategories varies according to the type of promoted product (vice or virtue). Design/methodology/approach: The methodology is based on different econometrical models that estimate the total net effect of price promotions of virtue and vice products on sales. Findings: The results show a greater own effect for price promotions of vice products than for virtue products. However, the complementary sales effect between subcategories for virtue products facilitates greater expansion of the subcategory in virtue products than in vice products. Originality/value: Although price promotions of virtue products (light) and vice products (regular) have proliferated in recent years, researchers have only estimated their own sales effect. Alternatively, the paper contributes by considering own and cross effects.

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Isobaric vapour–liquid and vapour–liquid–liquid equilibrium data for the water + 1-butanol + toluene ternary system were measured at 101.3 kPa with a modified VLE 602 Fischer apparatus. In addition, the liquid–liquid equilibrium data at 313.15 K were measured and compared with data from other authors at different temperatures. The system exhibits a ternary heterogeneous azeotrope whose temperature and composition have been determined by interpolation. The thermodynamic consistency of the experimental vapour–liquid and vapour–liquid–liquid data was checked by means of the Wisniak’s Li/Wi consistency test. Moreover, the vapour–liquid and the liquid–liquid equilibrium correlation for the ternary system with NRTL and UNIQUAC models, together with the prediction made with the UNIFAC model, were studied and discussed.

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Reconocido como una de las figuras clave en la difusión de la inoculación contra la viruela en España, el médico de origen irlandés Timoteo O'Scanlan dejó publicadas 3 obras y numerosos artículos de prensa en los que plasmó su pericia e interés por una práctica que se inició de forma tardía en nuestro país. Aceptado como miembro de la Real Academia Médica de Madrid en noviembre de 1778, leyó su discurso de ingreso en abril de 1779. El texto, que constituye la primera aproximación de O'Scanlan a la inoculación, que venía practicando con éxito desde 1771, fue incluido con algunas modificaciones y sin citar la fecha de redacción en la introducción de su primera obra, Práctica moderna de la inoculación (1784). El manuscrito se encuentra en el Archivo del Conde de Campomanes (Fundación Universitaria Española, Madrid).

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Background: Surveillance programmes have become the most effective tool for controlling catheter-related bloodstream infections (CRBSI). However, few studies have investigated programmes covering all hospital settings. Aim: To describe the results of a control and prevention programme for CRBSI based on compliance with recommendations for insertion and maintenance, using annual burden of disease in a tertiary level hospital. Methods: A CRBSI control and prevention programme involving all hospital settings was implemented. The programme consisted of CRBSI surveillance, direct observation of insertion and maintenance of catheters to determine performance, and education for healthcare workers. Findings: In total, 2043 short-term catheters were inserted in 1546 patients for 18,570 catheter-days, and 279 long-term catheters were inserted in 243 patients for 40,440 catheter-days. The annual incidence density was 5.98 (first semester 6.40, second semester 5.64) CRBSI per 1000 catheter-days for short-term catheters, and 0.57 (first semester 0.66, second semester 0.43) CRBSI per 1000 catheter-days for long-term catheters. One hundred and forty insertion procedures were observed, with an average insertion time of 13 (standard deviation 7) min. Compliance with recommendations was as follows: hand hygiene, 86.8%; use of alcoholic chlorhexidine solution for skin disinfection, 35.5%; use of mask, 93.4%; use of gloves, 98.7%; use of gown, 75.0%; use of sterile cloth, 93.8%; use of cap, 92.2%; bandage application, 62.7%; and use of aseptic technique, 89.5%. Forty-five maintenance procedures were observed, and compliance rates were as follows: hand hygiene, 42.1%; use of gloves, 78.1%; and port disinfection with alcoholic chlorhexidine solution, 32.5%. Conclusion: The CRBSI control and prevention programme implemented at the study hospital has decreased the rate of CRBSI, provided important information about the total burden of disease, and revealed possible ways to improve interventions in the future.

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The synthesis of nitrogenated carbon nanotubes (N-CNTs) with up to 6.1 wt% N, via the use of pyridine as the nitrogen containing carbon precursor, can provide a facile route to significantly enhance the low intrinsic specific capacitance of carbon nanotubes. The nitrogen functionalities determine this, at least, five-fold increase of the specific capacitance.

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Koninckinids are a suitable group to shed light on the biotic crisis suffered by brachiopod fauna in the Early Jurassic. Koninckinid fauna recorded in the late Pliensbachian–early Toarcian from the easternmost Subbetic basin is analyzed and identified as a precursor signal for one of the most conspicuous mass extinction events of the Phylum Brachiopoda, a multi-phased interval with episodes of changing environmental conditions, whose onset can be detected from the Elisa–Mirabile subzones up to the early Toarcian extinction boundary in the lowermost Serpentinum Zone (T-OAE). The koninckinid fauna had a previously well-established migration pattern from the intra-Tethyan to the NW-European basins but a first phase with a progressive warming episode in the Pliensbachian–Toarcian transition triggered a koninckinid fauna exodus from the eastern/central Tethys toward the westernmost Mediterranean margins. A second stage shows an adaptive response to more adverse conditions in the westernmost Tethyan margins and finally, an escape and extinction phase is detected in the Atlantic areas from the mid-Polymorphum Zone onwards up to their global extinction in the lowermost Serpentinum Zone. This migration pattern is independent of the paleogeographic bioprovinciality and is unrelated to a facies-controlled pattern. The anoxic/suboxic environmental conditions should only be considered as a minor factor of partial control since well-oxygenated habitats are noted in the intra-Tethyan basins and this factor is noticeable only in the second westward migratory stage (with dwarf taxa and oligotypical assemblages). The analysis of cold-seep proxies in the Subbetic deposits suggests a radiation that is independent of methane releases in the Subbetic basin.

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Nitrogen functionalization of a highly microporous activated carbon (BET surface area higher than 3000 m2/g) has been achieved using the following sequence of treatments: (i) chemical oxidation using concentrated nitric acid, (ii) amidation by acyl chloride substitution with NH4NO3 and (iii) amination by Hoffman rearrangement. This reaction pathway yielded amide and amine functional groups, and a total nitrogen content higher than 3 at.%. It is achieved producing only a small decrease (20%) of the starting microporosity, being most of it related to the initial wet oxidation of the activated carbon. Remarkably, nitrogen aromatic rings were also formed as a consequence of secondary cyclation reactions. The controlled step-by-step modification of the surface chemistry allowed to assess the influence of individual nitrogen surface groups in the electrochemical performance in 1 M H2SO4 of the carbon materials. The largest gravimetric capacitance was registered for the pristine activated carbon due to its largest apparent surface area. The nitrogen-containing activated carbons showed the highest surface capacitances. Interestingly, the amidated activated carbon showed the superior capacitance retention due to the presence of functional groups (such as lactams, imides and pyrroles) that enhance electrical conductivity through their electron-donating properties, showing a capacitance of 83 F/g at 50 A/g.

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Current economic crisis together with the Internet revolution has had direct impacts on the franchise sector of Spain: in particular on its unique communication network. The aim of this research is to analyse how Spanish franchise companies have adapted to these changes through its corporate communications management. We want to determine whether the management of communications is ideal to the growth and consolidation of companies in the market. Corporate communications plans and organizational structures were analyzed to verify whether or not information technology (i.e. the use of the Internet) is maximized: the communications aspect being a critical area of company growth. We found that most franchise companies surveyed had adapted well to the changes in information technology, despite economic challenges. The Internet as a communications tool has been limited to its utility as a “bulletin board” for information. The marketing advantage of Internet communication, or its use as an avenue for customer exchange and exchange of goods and services has yet to be maximized. Future research may look into the details of how companies are able to maximize the communications-marketing advantage that Online/Internet can contribute to the franchise sector.

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The economic design of a distillation column or distillation sequences is a challenging problem that has been addressed by superstructure approaches. However, these methods have not been widely used because they lead to mixed-integer nonlinear programs that are hard to solve, and require complex initialization procedures. In this article, we propose to address this challenging problem by substituting the distillation columns by Kriging-based surrogate models generated via state of the art distillation models. We study different columns with increasing difficulty, and show that it is possible to get accurate Kriging-based surrogate models. The optimization strategy ensures that convergence to a local optimum is guaranteed for numerical noise-free models. For distillation columns (slightly noisy systems), Karush–Kuhn–Tucker optimality conditions cannot be tested directly on the actual model, but still we can guarantee a local minimum in a trust region of the surrogate model that contains the actual local minimum.

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The Ossa de Montiel (2015/02/23, Mw 4.7) earthquake struck the central part of Spain and was felt far from the epicenter (> 300 km). Even though ground shaking was slight (Imax = V, EMS-98 scale), the earthquake triggered many small rock falls, most at distances of 20–30 km from the epicenter, greater than previously recorded in S Spain (16 km) for earthquakes of similar magnitudes. The comparative analysis of available data for this event with records from other quakes of the Betic cordillera (S and SE Spain) seems to indicate a slower pattern of ground-motion attenuation in central Spain. This could explain why slope instabilities occurred at larger distances. Instability was more frequent, and occurred at larger distances, in road cuts than in natural slopes, implying that such slope types are highly susceptible to seismically induced landslides.

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Concepts: %WL: Percentage of weight loss; %FL: Percentage of fat loss. Objective: evaluate which unit of measurement for weight loss could determine the success or failure of dietary treatment for overweight and obesity. Method: 4,625 consultations carried out on 616 patients in the southeast of Spain from 2006 to 2012. All of the patients were over 25 years of age and suffered from overweight or obesity. The consultations were carried out every fortnight, using the Mediterranean or low-calorie diet. The patients were divided into four groups according to their %WL and %FL. Results: most of the sample consisted of: women; participants between 25-45 years of age; attended consultations for over a month and a half; obese. 80% of the patients obtained a %FL ≥ 5% (15.5 ± 12.8). The groups with a higher %FL obtained significant differences in weight loss (22.6 vs 11.2%, p = 0.000). The multinomial analysis shows significant differences between the groups with the highest %FL and the lowest %WL and %FL: sex (p = 0.006 vs p = 0.005), BMI (p = 0.010 vs p = 0.003) and attendance (p = 0.000 vs p = 0.000). Conclusion: the patients who lost < 5% of fat had higher initial parameters (percentage of weight and fat); most of the sample lost ≥ 5% of fat. This means that the method of personalised dietary treatment results in a high fat loss; fat is an indicator of the quality loss obtained. Recommendations: use the measurement of fat as a complementary unit of measurement to weight loss; establish a limit of 5% to evaluate such loss; and increase this type of research in any method of weight loss.