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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Flexible Ignition System for a Gas Turbine

Berg, Anton January 2012 (has links)
Siemens Industrial Turbomachinery AB produce five gas turbines models. The SGT-700 can currently only start on gases which contain low amounts of inert gases. It is therefore of interest to widen the fuel range which the SGT-700, as well as other gas turbines, can start on. This report investigates the maximum limit of inert gases the SGT-700 will be able to start on, but also investigates if it is possible to start on liquid fuel (diesel) by making a few modifications to the gas turbine. To investigate this, the atmospheric combustion rig available at Siemens in Finspång has been used with a standard burner, igniter and ignition unit for the SGT-700. For the liquid fuel, the igniter was replaced by a torch igniter specially made for liquid fuels. Four different gases were evaluated; methane, propane, CO2 and N2 in order to see the effect of both various hydrocarbons and various inert gases. A model was developed for the gaseous experiments to estimate the limit for the maximum amount of inert gases the gas turbine would be able to start on. The model suggested that CO2 would require a larger amount of energy than N2 for the same amount in the composition, but that varying hydrocarbons did not have any effect if looking at the mass % of inert gas in the composition. The model was also extended with ethane and hydrogen but no experiments were performed with these gases. The model gave satisfying results. It overestimated the maximum amount of inert gases which could be mixed with propane, but agreed well when comparing the two inert gases with each other. Other interesting results were that an increased fuel flow decreased the minimum ignition energy and that an increased air flow gave a minor decrease in the maximum amount of inert gases that was possible to ignite. The torch igniter for the liquid fuel worked in a satisfying way. The ignition energy was however too low, so the ignition reliability was low. A new ignition unit with larger energy output therefore needs to be implemented. The igniter was fairly insensitive to variations in burner air flow and the ignition delay was small enough to provide a sustainable flame.
52

The C-economy, nutritional benefits and symbiotic performance of dual inoculated Phaseolus vulgaris (L.) plants, under variable nutrient conditions

Mortimer, Peter E January 2010 (has links)
Philosophiae Doctor - PhD / The tripartite symbiosis between Phaseolus vulgaris, arbuscular-mycorrhiza and the nodule bacteria, Rhizobia have been the focus of many studies ranging over a number of decades, however these studies have failed to answer certain questions relating the role of the symbionts in regard to host nutrition and the subsequent influence of these symbionts on the host C- economy. There is little doubt over the synergistic benefits involved in the dual inoculation of bean plants, as well as the resultant C-costs of maintaining the 2 symbionts, yet the specific contribution of the individual symbionts to the hosts overall nutrient and C-economy remain to be clarified. Thus the aim of this thesis is to help clarify these points by determining the symbiont induced photosynthetic, respiratory and nutritional changes taking place in the host. This was achieved by a series of experiments in which nodulated bean plants were split into two categories-those with and without AM colonized roots. These plants were then exposed to a range of growing conditions, including hi and low P, and a series of N treatments, ranging from zero N through to 3 mM NH/. Under these differing nutrient conditions growth, photosynthetic, respiratory, nutrient and amino acid responses were monitored, thus allowing for the determination of the symbionts influence on the host and the hosts reliance on the respective symbionts. Host reliance was noted most strongly under nutrient limiting conditions. Under low P treatment AM was the dominant symbiont as far as host C was concerned, allowing for the early establishment of the AM, thus ensuring the uptake of P for both host and nodule development. High P affected AM colonization to a greater extent than it did nodule dry weight and conversely the addition of N~ + led to a greater decrease in nodule dry weight than it did AM colonization. In spite of this decline, AM benefited the host by improving host N nutrition and relieving N-feedback inhibition of the export amino acid asparagine on BNF. These AM induced benefits did come at a cost to the host though, the dual inoculated plants had higher below ground respiratory costs and subsequently higher photosynthetic rates to compensate for the increased demand for C. The higher photosynthetic rates associated with dual inoculation were as a result of symbiont induced sink stimulation and not due to the improved nutrition of the host, as shown by the photosynthetic and nutrient response ratios. However, the respiratory costs associated with the uptake of soil nutrients were lower in AM colonized roots, thus showing an increased efficiency in nutrient gain by AM colonized roots. This improvement in host N nutrition as a result of AM colonization, coupled with the lower respiratory costs of AM nutrition led to the conclusion that under certain growing conditions nodules can become redundant and possibly parasitic.
53

Integration av webbaserat bokningssystem

Suomi-Olsson, Oskar January 2020 (has links)
Företaget M Hälsa Träning behövde ett bokningssystem där kunder kunde boka träff med personalen, systemet skulle integreras i deras redan befintliga webbsida. Den befintliga webbapplikationen byggde på ett CMS för hantering av data. Tidbokningssystemet behövde anpassas för att kunna användas tillsammans med CMS:et. Utvecklingen av systemet gjordes med webbramverket React.js samt en utbyggnad av redan befintlig webbserver arkitektur. Befintliga beroenden och verktyg användes i så stor utsträckning som möjligt. Utifrån M Hälsa Tränings beskrivning av önskad funktionalitet togs en kravlista för systemet fram. Reactdelen av systemet delades in i React komponenter som alla ansvarade för en specifik del av tidbokningssystemet. Komponenterna kommunicerade med ett API för att skicka och ta emot data. React redux användes för att hantera datat i reactdelen. Anpassningsbar data implementerades på servern i så stor utsträckning som möjligt för att kunna ändras i CMS:ets instrumentbräda. Implementeringen av funktionalitet på serversidan byggde på tidigare programmerares struktur och exempel. Resultatet av konstruktionen blev ett bokningssystem inbyggt i den existerande applikationen. Bokningssystemet är uppdelat i tre steg, en sida för att välja behandling, en kalender för att välja en tid och slutligen ett formulär för att fylla i personuppgifter och bekräfta bokning. Slutsatserna som kunde dras av arbetet var att denna tilläggsutveckling förde med sig både för och nackdelar, svårigheter så som okända och utdaterade verktyg och beroenden. Fel val av språk i och dålig planering av reactdelen. Fördelar med denna utveckling var den struktur och stomme som utvecklaren av M Hälsa Träning gjort, vilket förenklade utvecklingen av serverdelen då en tydlig struktur med goda exempel fanns att följa.
54

Effects of Binge Drinking and Depression on Cognitive-Control Processes During an Emotional Go/No-Go Task in College Aged Adults

Magee, Kelsey Elise 29 January 2019 (has links)
No description available.
55

Characterizing Electrocortical Profiles During Two Cognitive Tasks in Transitional Aged Youth With and Without Depression

Staff, Corrine 16 February 2022 (has links)
Depression in transitional aged youth (TAY; aged ~16-24yr) has become a major issue of concern, with 14-25% of those aged 12-21yr experiencing at least one episode of depression. As such, the burden of disease of depression in this population is substantial. Depression in TAY is characterized as a chronic, relapsing disorder, with 50-70% of remitted patients developing a subsequent depressive episode within five years. Further, in younger adulthood (~21-38yr) individuals who experience depression do not always show complete functional recovery between episodes and report residual cognitive impairments. However, research examining the neural correlates of putative cognitive impairments in depressed individuals has traditionally focused on adult populations, with more limited research in depressed TAY. One means of characterizing neural profiles during cognitive processing is via electroencephalography (EEG), and event-related potentials (ERPs) extracted from EEG. To date, it is unclear if ERP profiles during tasks tapping into certain cognitive processes known to be altered in depressed adults are comparable in depressed TAY. Greater insight into the neural features of cognitive processes in the context of depression can, ultimately, help in refining intervention and perhaps prevention strategies in depressed youth. The primary aim of this work was to assess ERP-indexed neural profiles of attention, including novelty orienting, and inhibition via the auditory oddball and visual flanker tasks in depressed, unmedicated TAY (DEP) vs. non-depressed TAY (HC). Specifically, the N2 and P3 ERPs elicited by incongruent and congruent stimuli in a visual flanker task were assessed, as were the P3a and P3b ERPs extracted from an auditory novelty oddball task. Further, behavioural scores on three tasks, measured by the National Institutes of Health (NIH) Toolbox, that tap into similar cognitive processes as the ERP tasks (i.e., executive function, stimulus evaluation, inhibition, and working memory) were compared between groups using well-validated cognitive tests. Finally, correlations were carried out on the entire sample’s cognition scores and ERP measures, as well as the DEP group’s clinical scores and ERP measures to explore the relation between behavioural and neural features. A significant difference was found between groups for the early P3a (eP3a) latency elicited by unexpected novel sounds in the oddball task; the DEP group had a significantly shorter latency than the HC group. For the flanker task, group differences were found for N2 amplitude to incongruent flanker stimuli, wherein the DEP group showed significantly higher amplitudes than the HC group. No group differences were found between composite scores of three NIH Toolbox tasks assessed. Correlations revealed a positive relation between the Dimensional Change Card Sort test (NIH Card Sort task), generally regarded as a test of executive function, and P3 amplitude to both congruent and incongruent stimuli on the ERP Flanker task. Second, a positive relation existed between the Flanker Inhibitory Control and Attention task (NIH Flanker) and P3 latency on the ERP Flanker task. This study failed to replicate previous reports of reduced ERP amplitudes and increased latencies of the oddball and flanker tasks in a depressed adult populations population. However, they contribute to our limited knowledge on the effects of depression in youth on cognitive processes and associated neuronal profiles. Indeed, the data suggest that non-severely depressed and unmedicated young people exhibited more efficient cortical processing to novelty orienting than matched controls, perhaps reflecting a hyper-vigilant state. Further, depressed TAY appeared to exhibit more pronounced cortical resource allocation to processes implicated in inhibition. Across all participants, we were also able to demonstrate a relation between better executive function and increased cortical resource allocation to attentive processes, and greater behavioural inhibition being associated with longer cortical processes of attention. Collectively, these data inform our understanding of the neural processes in young people with depression; such insight may aid in more refined intervention and prevention strategies in the future.
56

Neural Responses to Food Pictures and Their Association with Dietary Intake

Christenson, Edward 01 December 2012 (has links) (PDF)
BACKGROUND: Food-related visual cues may affect eating behavior and energy intake. The purpose of this study was to determine the neural response to pictures of food and whether or not the neural responses were associated with energy intake. METHODS: Using a cross-sectional design, 60 adults participated in this study. Each participant reported to the laboratory in a fasted state, were fitted with a 128-electrode electroencephalogram (EEG) net, and were shown pictures grouped into three categories: high-calorie foods, low-calorie foods, and distractor pictures. These pictures were shown in random order. Furthermore, participants were shown these pictures in one passive condition and two active conditions (also in random order). The passive condition required participants to view pictures in a relaxed state while neural responses were recorded. The active conditions required participants to be actively engaged with the picture by pressing or withholding a specified button on a keyboard (go/no go task). The active conditions included only high- and low-calorie foods. Event Related Potentials (ERP) of interest were the N2, P300, and late positive potential (LPP). The National Cancer Institute's Automated Self-administered 24-hour Dietary Recall (ASA24) was used to assess energy and macronutrient intake. RESULTS: The N2 amplitude, when amplitude for high-calorie pictures is subtracted from the amplitude of low-calorie pictures, was significantly different for each active condition (F = 41.23; p < 0.0001). However, neural responses to picture-type for the N2, P300 and LPP were not different (p > 0.05). The difference in N2 amplitude, for the high-calorie no go condition that results from the amplitude for low and high-calorie pictures being subtracted from each other, was significantly associated with carbohydrate intake (r = -0.263) and significantly predicted carbohydrate intake (regression coefficient = -56.821; p = 0.043) but not energy, fat, or protein intake (p > 0.05). Neither the P300 nor the LPP was correlated with or predicted energy and macronutrient intake (p > 0.05). CONCLUSION: The N2 differentiates depending on the no go stimulus. The difference in N2 amplitude, for the high-calorie no go condition, may be an index of carbohydrate intake. The P300 and LPP do not appear to differentiate between pictures of high- and low-calorie foods, nor do they correlate with energy or macronutrient intake.
57

Age-Related Differences in Food-Specific Inhibitory Control: Electrophysiological and Behavioral Evidence in Healthy Aging

Allen, Whitney D. 28 April 2022 (has links) (PDF)
The number of older adults is estimated to double from 52 million to 95 million by 2060. Approximately 80-85% of older adults are diagnosed with a chronic health condition. Many of these chronic health conditions are influenced by diet and exercise, suggesting improved diet and eating behaviors could improve health-related outcomes. One factor that might improve dietary habits in older adults is food-related inhibitory control. We tested whether food-related inhibitory control, using behavioral (response time, error rate) and scalp-recorded event-related potential (ERP; N2 and P3 components) measures of food-related inhibitory control differed between younger and older adults over age 55. Fifty-nine older adults (31 females [52.5%], Mage=64, SDage=7.5) and 114 younger adults (82 females [71.9%], Mage=20.8) completed two go/no-go tasks, one inhibiting to high-calorie stimuli and one inhibiting to low-calorie stimuli, while electroencephalogram (EEG) data were recorded. Older adults had slower overall response times than younger adults, but this was not specific to either food task. There was not a significant difference for accuracy between younger and older adults, but both groups' accuracy and response times were significantly improved during the high-calorie task than the low-calorie task. For both the N2 and P3 ERP components, younger adults had greater amplitude than older adults, but this effect was not food-specific, reflecting overall generalized lower inhibitory processing in older adults. Of note, P3 amplitude for the younger adults demonstrated a specific food-related effect (greater P3 amplitude for high-calorie no-go) that was not present for older adults. Findings support previous research demonstrating age related differences in inhibitory control though those differences may not be specific to inhibiting to high-calorie foods.
58

Response Inhibition to High Calorie Food Cues Among Adolescents Following Active and Sedentary Video Game Play Using a Go/No-Go Task: A Randomized Crossover Study

Smith, Joshua L 01 December 2017 (has links)
Sedentary behaviors, such as leisure time computer use and sedentary video games, are significant barriers to regular physical activity and contribute to high rates of overweight and obesity among adolescents. Sedentary screen time can adversely affect food intake and food selection. Active video games may be a promising way of increasing daily physical activity levels among adolescents. Active video games may help modulate response inhibition and food intake. PURPOSE: Compare the effects of an acute bout of active and sedentary video gaming on N2 amplitudes (while viewing high calorie and low calorie images), Stroop Color Word Test (Stroop test) performance and ad libitum eating. METHODS: We used a within-subjects randomized crossover design with counterbalanced treatment conditions was used among 65 participants (31 girls, 34 boys; age = 13.5 ± 1.1 year; height = 161.4 ± 10.2 cm; weight = 52.5 ± 12.3 kg; BMI = 19.9 ± 3.3 kg·m2). Participants completed 2 separate video gaming sessions, 7 days apart, while energy expenditure during sedentary and active video game play was measured using the K4b2 portable metabolic system. The K4b2 system provided metabolic equivalents (METs) which are used as a measure of energy cost of physical activity. After either 60 minutes of active or sedentary video game play, participants completed a go/no-go task while viewing high calorie and low calorie images while electroencephalogram (EEG) data were collected. N2 event related potential (ERP) amplitudes were measured during the viewing task. Participants also completed a Stroop task to measure response inhibition. Finally, participants were given high calorie and low calorie snacks to consume ad libitum. We used a repeated measures ANOVA was used to measure main and interaction effects for N2 ERP amplitudes within subjects. RESULTS: Active video game play relative to sedentary video games significantly increased METs (F = 543.1, p ‰¤ 0.0001) from 1.7 ± 0.35 to 5.0 ± 1.2 METs. A significant gender-by-condition interaction (F = 7.03, p ‰¤ 0.009) was observed for energy expenditure with boys (5.4 ± 1.1 METs) expending more energy during the active video game than girls (4.5 ± 1.1 METs). No significant differences were observed for the N2 component (F = 0.50, p = 0.48) between video game conditions nor between genders (F = 1.85, p = 0.17). There were no significant differences (F = 3.10, p = 0.08) in the total number of calories consumed between the 2 video gaming conditions. Results from the Stroop task showed no significant differences for word naming (F = 0.45, p = 0.49), congruent condition (F = 0.43, p = 0.52) and incongruent condition (F = 0.14, p = 0.71) between the active and sedentary video games. CONCLUSION: Sixty minutes of active video gaming increases energy expenditure to a moderate intensity level but does not alter behavioral response or response inhibition to high calorie or low calorie foods.
59

Response Inhibition to High Calorie Food Cues Among Adolescents Following Active and Sedentary Video Game Play Using a Go/No-Go Task: A Randomized Crossover Study

Smith, Joshua L 01 December 2017 (has links)
Sedentary behaviors, such as leisure time computer use and sedentary video games, are significant barriers to regular physical activity and contribute to high rates of overweight and obesity among adolescents. Sedentary screen time can adversely affect food intake and food selection. Active video games may be a promising way of increasing daily physical activity levels among adolescents. Active video games may help modulate response inhibition and food intake. PURPOSE: Compare the effects of an acute bout of active and sedentary video gaming on N2 amplitudes (while viewing high calorie and low calorie images), Stroop Color Word Test (Stroop test) performance and ad libitum eating. METHODS: We used a within-subjects randomized crossover design with counterbalanced treatment conditions was used among 65 participants (31 girls, 34 boys; age = 13.5 ± 1.1 year; height = 161.4 ± 10.2 cm; weight = 52.5 ± 12.3 kg; BMI = 19.9 ± 3.3 kg·m2). Participants completed 2 separate video gaming sessions, 7 days apart, while energy expenditure during sedentary and active video game play was measured using the K4b2 portable metabolic system. The K4b2 system provided metabolic equivalents (METs) which are used as a measure of energy cost of physical activity. After either 60 minutes of active or sedentary video game play, participants completed a go/no-go task while viewing high calorie and low calorie images while electroencephalogram (EEG) data were collected. N2 event related potential (ERP) amplitudes were measured during the viewing task. Participants also completed a Stroop task to measure response inhibition. Finally, participants were given high calorie and low calorie snacks to consume ad libitum. We used a repeated measures ANOVA was used to measure main and interaction effects for N2 ERP amplitudes within subjects. RESULTS: Active video game play relative to sedentary video games significantly increased METs (F = 543.1, p ≤ 0.0001) from 1.7 ± 0.35 to 5.0 ± 1.2 METs. A significant gender-by-condition interaction (F = 7.03, p ≤ 0.009) was observed for energy expenditure with boys (5.4 ± 1.1 METs) expending more energy during the active video game than girls (4.5 ± 1.1 METs). No significant differences were observed for the N2 component (F = 0.50, p = 0.48) between video game conditions nor between genders (F = 1.85, p = 0.17). There were no significant differences (F = 3.10, p = 0.08) in the total number of calories consumed between the 2 video gaming conditions. Results from the Stroop task showed no significant differences for word naming (F = 0.45, p = 0.49), congruent condition (F = 0.43, p = 0.52) and incongruent condition (F = 0.14, p = 0.71) between the active and sedentary video games. CONCLUSION: Sixty minutes of active video gaming increases energy expenditure to a moderate intensity level but does not alter behavioral response or response inhibition to high calorie or low calorie foods.
60

Regeneración electroquímica de carbón activado usado en plantas potabilizadoras de agua: escalado, optimización y validación de prototipos

Ferrández-Gómez, Borja 17 September 2021 (has links)
El estudio que da lugar a la presente Tesis Doctoral está motivado por la necesidad de escalar los reactores para llevar a cabo la regeneración electroquímica de carbones activados (CAs), así como por la necesidad de optimizar las variables experimentales más relevantes de este proceso con el fin de conseguir una tecnología eficiente con el menor coste posible. El CA es un material ampliamente utilizado en la industria por su capacidad de adsorción, pero, para que sea viable económicamente, es necesario que se desarrollen tecnologías que sean capaces de recuperar las propiedades texturales iniciales y, por tanto, que se pueda reutilizar. En este sentido, la tecnología aplicada actualmente a nivel industrial es la regeneración térmica. Una alternativa que puede suponer una mejora desde el punto de vista medioambiental y económico se encuentra la regeneración electroquímica que está desarrollada a escala de laboratorio. Por tanto, el objetivo principal de la presente Tesis Doctoral es el estudio de la regeneración electroquímica de CAs gastados en condiciones reales en diferentes estaciones de tratamiento de agua potable empleando diferentes reactores electroquímicos a distinta escala. La presente Tesis Doctoral se basa en la regeneración electroquímica de CAs a escala de planta piloto. En primer lugar, se estudia el proceso de escalado del reactor electroquímico desde un nivel de laboratorio (6 g de capacidad) hasta escala de planta piloto (15 kg de capacidad), teniendo un reactor intermedio a escala de banco (3.5 kg de capacidad). Para ello, se diseñan dos reactores en configuración de placas paralelas y un prototipo alternativo en configuración de electrodos cilíndricos concéntricos. En segundo lugar, se optimizan las diferentes variables experimentales con el objetivo de alcanzar la mayor eficiencia de regeneración al menor coste posible. Los parámetros objeto de estudio son: tipo de regeneración, configuración del reactor electroquímico, tipo, concentración y caudal de electrolito, tiempo de tratamiento y composición del material de los electrodos. Además, se han regenerado diferentes CAs usados durante 3-10 años en varias industrias de tratamiento de aguas y químicas. Por último, se realiza un ensayo de adsorción en disolución de un contaminante emergente como el bisfenol A sobre los CAs regenerados electroquímicamente con el fin de demostrar que pueden volver a aplicarse como material adsorbente de garantías. Los resultados de esta investigación han conducido a las siguientes conclusiones generales: 1. El proceso de escalado desde la celda electroquímica filtro-prensa con una capacidad de 6 g de CA hasta dos reactores electroquímicos con configuración de placas paralelas con capacidad para 3.5 y 15 kg de CA no puede ser directo debido al tamaño inviable del reactor y de las necesidades de la fuente de alimentación. Para evitar estos problemas, se propone un escalado modificado en el que los parámetros de distancia entre electrodos, tiempo de residencia, volumen específico de electrolito en el tanque y concentración de electrolito, se cambian para alcanzar unos parámetros de diseño aceptable para la construcción y funcionamiento de los reactores. 2. Se han diseñado y construido dos reactores electroquímicos con configuración de electrodos planos paralelos con capacidad para 3.5 y 15 kg, respectivamente. La regeneración electroquímica del CA usado en condiciones reales se puede lograr con una recuperación de la porosidad superior al 95% utilizando ambos reactores. 3. Las condiciones experimentales que permiten alcanzar, con estos CAs saturados en condiciones reales, una eficiencia de regeneración superior al 95% en un reactor electroquímico filtro-prensa son: ácido sulfúrico 0.05 M como electrolito, densidad de corriente de 0.025 A/cm2, con separación de compartimentos y el CA colocado en el compartimento catódico. 4. Las condiciones más favorables para lograr una eficiencia de regeneración, con estos CAs saturados en condiciones reales, superior al 95% empleando un reactor de electrodos de placas paralelas a escala laboratorio con capacidad para 3.5 kg de CA son: configuración con separación de compartimentos, regeneración catódica, densidad de corriente de 0.025 A/cm2 y ácido sulfúrico 0.5 M como electrolito. Sin embargo, tras el tratamiento electroquímico, se produce una oxidación parcial del CA. Finalmente, se concluye que el acero inoxidable puede utilizarse como material catódico y que, a partir de la cuarta hora de tratamiento, el aumento en la eficiencia de regeneración es despreciable. 5. La regeneración electroquímica también se puede lograr de manera satisfactoria utilizando el reactor diseñado a escala de planta piloto con electrodos de placas paralelas. En las condiciones experimentales adecuadas (0.5 M y 750 L/h como caudal de electrolito, Pt/Ti como ánodo y acero inoxidable como cátodo, 70 A de intensidad durante 2 h) se obtiene una recuperación de la porosidad superior al 95%. Por otra parte, la oxidación producida por el tratamiento electroquímico tiene poca influencia ya que la mayor cantidad de grupos oxigenados producidos en la superficie el material se debe al uso de este en la ETAP, puesto que el tratamiento con CA se encuentra tras el tratamiento de desinfección del agua, y las especies oxidantes alcanzan el CA produciendo su oxidación. 6. Se ha diseñado y construido un reactor electroquímico con configuración de electrodos cilíndricos concéntricos de capacidad 10 kg de CA. La regeneración electroquímica del CA usado en condiciones reales se puede obtener con una recuperación de la porosidad superior al 95% utilizando este reactor electroquímico a escala de planta piloto. 7. Las condiciones experimentales óptimas para lograr un 95% de eficiencia de regeneración con el reactor a escala de planta piloto de electrodos concéntricos cilíndricos son: ácido sulfúrico 0.25 M como electrolito y un flujo de 750 L/h, Pt/Ti como ánodo, acero inoxidable como cátodo y 27 A de intensidad durante 2 h. Por otra parte, se debe destacar que los reactores propuestos a escala de planta piloto presentan una reducción del consumo energético del 98% en comparación con la fabricación de CA y, superior al 90%, en comparación con la tecnología de regeneración térmica convencional. 8. Del proceso de validación en la celda filtro-prensa se concluye que, para lograr una eficiencia de regeneración satisfactoria, el área superficial del CA gastado debe ser superior a 600 m2/g, mismo valor solicitado por empresas de regeneración térmica. En el caso de CAs impregnados con álcalis, se puede lograr una buena recuperación de la porosidad. Sin embargo, habría que aplicar un tratamiento de impregnación posterior para tener las mismas características que el material de partida. Por otra parte, los CAs que no pueden regenerarse térmicamente difícilmente pueden regenerarse por el método electroquímico. Finalmente, hay que destacar que cada CA gastado necesita unas condiciones experimentales de regeneración particulares, especialmente dependiendo de la industria que lo genera. 9. La validación del prototipo a escala de banco con capacidad para 3.5 kg pone de manifiesto que los CAs fabricados mediante aglomeración se regeneran con mayor facilidad que los preparados por el método de activación directa; además, al igual que en el caso del estudio en célula filtro-prensa, el área superficial del CA usado debe ser superior a 600 m2/g para conseguir una buena eficiencia en la regeneración. De esta forma, se comprueba la viabilidad del método electroquímico para la regeneración de CA usado en condiciones reales a nivel industrial; por tanto, se puede considerar como una alternativa al método de regeneración térmica actual. 10. La adsorción de bisfenol A en CAs regenerados electroquímicamente demuestra que, aun presentando una cinética más lenta que la observada en el CA original, se pueden reutilizar para la adsorción de compuestos orgánicos.

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