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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.
251

Mise en place d’une brique géopolymère pour la construction durable : études géotechnique, environnementale et économique / Geopolymer brick implementation for sustainable construction : geotechnical, environmental and economic studies

Youssef, Nicolas 14 June 2019 (has links)
Après la crise économique en 2008, l’activité de construction en France a connu une croissance très rapide. La hausse de la demande des matériaux de construction était accompagnée d’une augmentation des quantités de déchets de construction et de CO2 émise. En 2018, l’émission de CO2 liée aux activités humaines a atteint un niveau historique mondial de 37.1 milliards de tonnes. Ceci encourage le développement des matériaux de construction qui répondent aux besoins mutants de la société d’aujourd’hui et de demain. Les géopolymères, préparés par activation alcaline, présentent une opportunité pour produire des nouveaux matériaux plus performants et respectueux de l’environnement dans le secteur de la construction. D’autre part, l’industrialisation et la robotisation font apparition dans le secteur de la construction, avec des nombreux avantages tels que l’augmentation de la productivité, la réduction des gaspillages, du coût et de la pénibilité du travail, ainsi que l’amélioration de la qualité et la sécurité.Ce travail de recherche est mené pour répondre à ces défis et verrous scientifiques. Il est réparti selon trois axes : l’élaboration de nouvelles formulations de briques géopolymères, l’intégration des matériaux géopolymères dans le processus d’industrialisation et de robotisation de la construction, et enfin l’évaluation de l’impact environnemental et économique du nouveau système de fabrication automatisé. / After the economic crisis in 2008, construction activity in France grew rapidly. The increase in demand for building materials was accompanied by an increase in the quantities of construction waste and emitted CO2. In 2018, CO2 emissions from human activities reached a world historic level of 37.1 billion tons. This encourages the development of building materials that meet the changing needs of today's and tomorrow's society. Geopolymers, prepared by alkaline activation, present an opportunity to produce new, more efficient and environment-friendly materials in the construction sector. On the other hand, industrialization and robotization are emerging in the construction sector, with many benefits such as increased productivity, reduced waste, cost and arduous work, as well as improved quality and safety.This doctoral thesis is being conducted to address these scientific challenges and issues. These are divided into three research directions: the development of new geopolymer brick formulations, the integration of geopolymer materials into the industrialization and robotization of construction processes, and finally the environmental and economic assessment of the new automated manufacturing system.
252

Interaction of gold mine taillings leachates with soil and geochemical partitioning of toxic metal species

Ngoetjane, Pitsi Christopher 02 February 2016 (has links)
Department of Ecology and Resource Management / MENVSC
253

Microbiological and physico-chemical quality of surface and groundwater sources and its socio-economic impact in the Mpheni - Elim Village, Limpopo Province, South Africa

Maluleke, H. L. 02 1900 (has links)
MESHWR / Department of Hydrology and Water Resources / See the attached abstract below
254

The effect of malting and fermentation on the nutritional and potential health-promoting properties of finger millet [Eleusine coracana (L.) Gaertn] grain

Udeh, Henry Okwudili 21 September 2018 (has links)
PhD (Food Science) / Department of Food Science and Technology / Finger millet (FM) [Eleusine coracana] is an underutilised cereal grain used as a food source in South Africa. Increased research interest in FM has span over the years owing to its unique nutritional and bioactive composition. Following the recent interest in natural curative substances over their synthetic counterparts in the treatment of food dependent diseases, FM has shown potential nutraceutical effects. Some important health effects like antidiabetic, antioxidative, anti-inflammatory and antimicrobial properties have been reported in recent trials with FM. In view of the increasing utilisation and application of FM in the region of Thulamela Municipality, Vhembe District of South Africa, two common indigenous FM varieties (brown and dark brown) were obtained and analysed for their physicochemical properties, levels of minerals, phytic acid, phenolic compounds and antioxidant activities. For this process, malted non-alcoholic beverages were produced and analysed for their physicochemical properties, levels of phenolic compounds, and total phenolics and antioxidant activities. FM grains were soaked, germinated and kilned at an interval of 24 h for 96 h, using sorghum as an external reference. Mineral composition of the FM and sorghum samples were analysed using an inductively coupled plasma atomic emission spectroscopy (ICP-AES) and mass spectroscopy (ICP-MS), and atomic absorption spectrometer (AAS). Identification and quantification of phenolic compounds were performed using ultra-performance liquid chromatography mass spectrometer (UPLC-MS). All experiments were performed in triplicate except for the UPLC-MS analysis of the malted non-alcoholic beverages that was done in duplicate. Data were analysed by one way analysis of variance, and the mean values were separated by Duncan’s multiple comparison test using SPSS version 24.0. Data showed that the FM varieties were rich in macro- and micro- or trace elements. The macro-elements calcium, magnesium, potassium, phosphorus and sulphur were found in high amounts ranging from 1597.37 mg/ kg – 6775.03 mg/ kg; iron, zinc, strontium and silicon were found in significant amounts in the range 21.47 mg/ kg – 55.67 iii mg/ kg, copper and boron were found in low amounts (2.2 mg/ kg – 7.7 mg/ kg), along with selenium and cobalt (0.02 mg/ kg – 0.05 mg/ kg). Heavy metals, barium and aluminium were found in the FM varieties. Varietal difference was found to play an important role in the mineral content of the grains during malting. Malting for 24 h reduced mineral content except for sodium. Beyond 48 h of malting, mineral content increased, particularly, for 96 h in FM grain malt. Significant (p < 0.05) increases in the mineral content of FM varieties were noted at 48 h and 96 h of malting. Increase occurred at 72 h of malting for potassium, iron and boron. Malting did not have any effect on the manganese content of the dark brown FM; however, it increased the manganese content at 48 h of malting for brown FM. Malting for 96 h significantly (p < 0.05) reduced sodium content. Consecutive decrease in phytic acid content of the grains was not recorded with durations in malting time. Although statistically significant differences (p < 0.05) were observed, malting did not result in too much change in the physicochemical properties of the grains. Several flavonoids, catechin, epicatechin, quercetin, taxifolin, and hesperitin were isolated, whilst protocatechuic acid was the only phenolic acid detected in the unmalted and malted FM. Increases in catechin, epicatechin and protocatechuic acid were observed for 72 and 96 h malt of brown FM with similar observations recorded for sorghum. Complete loss of taxifolin, catechin, and hesperitin were noted with malting time. FM grains exhibited 2, 2-diphenyl-1-picrylhydrazyl (DPPH), 2, 2՛-azinobis-3-ethylbenzthiazoline-6-sulfonic acid (ABTS) radical scavenging action and iron reducing activities. Increased iron reducing activity alongside ABTS radical scavenging activity was recorded with malting time. A fermentation-time dependent decrease in the pH of the non-alcoholic beverages, with a corresponding increase in sugar content were recorded. A similar decrease was also recorded for the viscosities of the beverages. The FM malt beverages were found to contain a higher amount of citric acid compared to the sorghum malt beverage. A decrease in the citric acid content with fermentation time was noted in the grain malt beverages fermented with Lactobacillus fermentum, particularly for the iv FM beverage. The phenolic compounds detected in the FM malt beverages fermented with the grain microbial flora and Lactobacillus fermentum were protocatechuic acid, catechin and epicatechin. Taxifolin and kaempferol along with the earlier mentioned compounds were detected in the sorghum malt beverage. Catechin was found in higher amount compared to other phenolic compounds in the FM and sorghum malt beverages. FM malt beverages were found to contain a higher amount of total phenolics compared to the beverage prepared from sorghum malt. Fermentation with the grains’ microbial flora and L. fermentum resulted in reduced total phenolics of FM and sorghum malt beverages, particularly after 24 h of fermentation. A fermentation-time dependent decrease in total phenolics of FM beverages fermented with L. fermentum was noted. Fermentation within 24 - 48 h using the grain microbial flora showed higher total individual phenolic compounds for the dark brown FM and sorghum, compared to other fermentation periods. Fermentation of the beverages for 24 h retained a higher amount of the total phenolics compared to other fermentation periods, especially for the L. fermentum beverages. Reduced total phenolic content and antioxidant activity of the beverages were noted at 24 h of fermentation for the two microbial sources. Significant (p < 0.05) increases in total phenolics were observed within 72 – 96 h of fermentation of the brown FM malt beverage with the grains’ microbial flora. Fermentation for 72 h and 96 h with L. fermentum increased the total phenolic content of the brown FM. Increase in total flavonoid content (TFC) of brown FM malt beverage was noted at 72 h fermentation for both microbial sources. Unlike with L. fermentum, no significant (p > 0.05) change in TFC was observed for the dark brown FM beverage after 24 h fermentation with the grains’ microbial flora. Beverages exhibited DPPH, ABTS radical scavenging action and iron reducing activities, which were significantly (p < 0.05) reduced at 96 h fermentation for both microbial sources. The 24 h fermented beverage retained a higher amount of total phenolic and flavonoid contents, and had higher antioxidant activity compared to other fermentation periods for both microbial sources. The study shows that FM is a rich source of essential minerals and v phenolic compounds, and demonstrates that 72 to 96 h of malting has a positive effect on minerals and certain phenolic compounds over the 48 h malting period widely used for preparation of FM malt. The presence of hesperitin in FM grain was established. A new method was developed for the production of FM non-alcoholic beverage with measurable amounts of health-promoting compounds. An ideal fermentation period (24 h) for FM malt non-alcoholic beverage production with enhanced health-promoting compounds, using Lactobacillus fermentum was demonstrated. Fermentation limit (96 h) for production of FM malt beverage using either the grain microbial flora or L. fermentum was confirmed. These findings provide a rationale for increased utilisation of FM as a functional food grain, and its use as malt in production of non-alcoholic beverage for health promotion and wellness. / NRF
255

Etude microclimatique et pédologique de l'effet de lisière en Cuvette centrale congolaise: impact écologique de la fragmentation des écosystèmes :cas des séries Yangambi et Yakonde à la région de Yangambi, R.D. Congo

Alongo Longomba, Sylvain 05 July 2013 (has links)
L’occupation du sol en zone forestière de Yangambi dans la Cuvette centrale congolaise (RDC) change rapidement et la fragmentation forestière liée à l’agriculture itinérante sur brûlis est devenue l’un des processus dominant la dynamique paysagère. La présente étude s’est fixée comme objectif de suivre une approche microclimatique en transects pour déterminer la zone de lisière entre les jachères herbeuses et les forêts denses, et ce, afin de mieux comprendre les réponses des propriétés physico-chimiques du sol aux changements d’occupation du sol et à la fragmentation forestière. Deux zones les plus appréciées par les paysans pour leurs exploitations agricoles ont été choisies en fonction des unités pédologiques existantes :la série Yangambi et la série Yakonde. Des échantillons non perturbés du sol de 0-10, 10-20 cm, 20-30 cm et perturbés de 0-20 cm ont été prélevés dans les différentes occupations de sols après la détermination de la zone de lisière. Notre démarche a consisté à comparer les propriétés de sols identiques au plan de leur pédogenèse, sous jachère herbeuse, sous lisière et sous couvert forestier, de façon à quantifier l’effet de lisière sur les propriétés des sols, pour mieux connaître les conséquences édaphiques de la fragmentation des forêts par l’agriculture itinérante sur brûlis. <p>Les résultats obtenus ont montré que la zone de lisière entre les jachères et les forêts denses a une largeur de 70 m pour la série Yangambi et 68 m pour la série Yakonde. Les variations microclimatiques de la lisière en terme de température de l’air, sont intermédiaires (moyenne, minima et maxima) entre celles des jachères herbeuses et des forêts denses. La fragmentation des forêts par l’agriculture itinérante sur brûlis modifie profondément les propriétés physico-chimiques de sols dans les couches superficielles. Un des effets de changements d’occupation du sol et de la fragmentation est la présence d’horizons superficiels à texture sableuse au niveau des jachères herbeuses et des lisières forestières. La densité apparente et la conductivité hydraulique ont subit une importante dégradation sous les jachères herbeuses. A l’inverse, la lisière forestière assure une bonne structure conservatrice du sol (faible densité apparente et bonne conductivité hydraulique). Le sol des forêts denses présente des bonnes propriétés physiques et de ce fait, est pris comme référence à partir duquel les effets de dégradation physique du sol peuvent être appréciés. <p>Le potentiel chimique du sol (pH, phosphore assimilable, le taux de saturation en bases et la CECE) est meilleur au niveau des jachères herbeuses et des lisières forestières par rapport aux forêts denses suite à la pratique du brûlis qui permet de restituer au sol une fraction de la minéralomasse forestière par les cendres. Les teneurs en carbone et azote totaux du sol ont été significativement plus élevées sous les lisières forestières que sous les jachères herbeuses et les forêts denses. Les résultats de l’indice de Kamprath ont montré que, les lisières, en plus de contribuer à l’accroissement de carbone organique du sol, tendent à diminuer la toxicité aluminique de sols étudiés. A l’inverse, l’étude a mis en évidence une toxicité aluminique plus élevée sous la jachère herbeuse de la série Yangambi que sous la lisière. En parallèle, nous avons observé une baisse des teneurs en fer sous toutes les jachères et les lisières forestières. <p>Les pratiques de jachères cultivées et d’agroforesterie s’avèrent incontournables pour enrichir ces sols en matière organique, limiter l’érosion liée au brûlis afin de freiner le lessivage des nutriments, éviter le compactage du sol et assurer le maintien à long terme d’une bonne structure conservatrice du sol.<p><p>In the forest zone of Yangambi, located in the Central Congo Basin (DRC), land use is changing rapidly and forest fragmentation due to slash and burn agriculture has become one of the dominant processes of landscape dynamics. This study's main goal is to apply a microclimatic approach in transects to determine the edge area between the fallow grasslands and dense forests, and, in order to better understand the responses of the soil physico-chemical properties to changes in land use and forest fragmentation. Two most popular areas used by farmers have been selected on the basis of the existing soil units: the Yangambi and Yakonde series. Undisturbed soil samples at depths of 0-10 cm, 10-20 cm, 20-30 cm and the disturbed at 0-20 cm were collected from different the land use types after detecting the edge area. Our approach was to compare the properties of identical soils based on their genesis, under grass fallow, edge and forest cover, so as to quantify the effect of edge on the soil properties, to better understand the edaphic consequences of the forest fragmentation by slash and burn shifting cultivation. <p>The results showed that the edge area between fallow and dense forests has a width of 70 m for the Yangambi series and 68 m for the Yakonde series. Microclimatic variations of the edge in terms of air temperature are intermediate (average, minimum and maximum) between grass fallows and dense forests. The fragmentation of forests by slash and burn shifting cultivation profoundly modifies the physico-chemical properties of soils in the surface layers. One of the effects of changes in land use and fragmentation was the presence of surface layers with more sandy texture in the fallow grassland and forest edges. Bulk density and hydraulic conductivity undergo an important degradation under grass fallows. In contrast, the forest edge ensures a maintenance of the soil structure (low bulk density and good hydraulic conductivity). Dense forest soil has thus good physical properties and therefore is taken as the reference from which the effects of soil physical degradation can be appreciated. <p>The chemical potential of the soil (based on pH, available phosphorus, base saturation and CECE) is better in the grass fallows and forest edges compared to dense forests due to the practice of slash and burn which allows restoration by adding nutrients to the soil through the ashes. The carbon and total nitrogen in the soil were significantly higher under forest edges than in fallow grasslands and dense forests. The results of the-Kamprath index shows the edges, in addition to contributing to an increase in soil organic carbon, tend to decrease the aluminium toxicity of studied soils. By contrast, the study revealed a higher aluminium toxicity under fallow grassland on the Yangambi series that under the edge and the forest. In parallel, we observed a decrease in iron contents in all fallow lands and forest edges. <p>The practices of cultivated fallows and agroforestry are proving unavoidable for enriching these soils in organic material, to reduce erosion related to slash and burn in order to curb the leaching of nutrients, to avoid soil compaction and to maintain a long-term well developed soil structure.<p><p> / Doctorat en Sciences agronomiques et ingénierie biologique / info:eu-repo/semantics/nonPublished
256

Effect of Rootstock on the Fruit Quality of Mandarins "Clemenules" and "Tango", and Blood Oranges "Tarocco Rosso" and "Moro"

Morales Alfaro, Julia 03 May 2021 (has links)
Tesis por compendio / [ES] La citricultura se enfrenta a escenarios ambientales cambiantes que provocan diferentes estreses bióticos y abióticos que pueden dificultar la producción o afectar a la calidad de la fruta. El patrón sobre el cual se injerta una variedad específica es una importante herramienta para mejorar su adaptabilidad a cada área de cultivo. En la presente Tesis se realiza el estudio del efecto del patrón sobre la calidad físico-química y nutricional de la fruta en variedades de gran interés comercial en la actualidad, mandarinas 'Clemenules' y 'Tango' y naranjas sanguinas 'Tarocco Rosso' y 'Moro'. En 'Clemenules' se llevó a cabo la evaluación de la calidad de la fruta de árboles injertados sobre ocho patrones en tres momentos de cosecha durante dos campañas. Los patrones Forner-Alcaide 13 y C-35 destacaron por adelantar el cambio de color, lo que es de gran interés comercial. Por otra parte, Forner-Alcaide V17 destacó por mantener niveles óptimos de acidez hasta el final de la campaña y presentar el mayor contenido en vitamina C, flavonoides, glucosa y fructosa. Carrizo Citrange también indujo altas concentraciones de sacarosa y vitamina C. 'Tango' es una mandarina de reciente introducción en el área mediterránea de gran interés por su periodo de recolección tardío. En esta Tesis se abordó el estudio de los cambios en la calidad fisicoquímica, nutricional y sensorial de la mandarina 'Tango' injertada sobre dos patrones (Carrizo Citrange y Forner-Alcaide 5) en las dos áreas principales de producción de Andalucía. Los resultados revelaron que la calidad de la fruta se vio influenciada por la localización de las parcelas, lo que se relacionó con la composición de la textura del suelo. En ambas localizaciones, Forner-Alcaide 5 indujo mayor contenido en acidez, sólidos solubles totales, sacarosa, vitamina C y ácido cítrico en la fruta. Las determinaciones físico-químicas, junto con la evaluación sensorial permitieron establecer el momento óptimo de recolección dependiendo de las diferentes condiciones estudiadas. También se ha incluido un estudio del comportamiento postcosecha de esta variedad, ya que no existían datos en nuestras condiciones de cultivo. La mandarina 'Tango' presentó síntomas externos de daños por frío a partir de los 20 días almacenada a 1°C y 5°C. Se realizó un estudio micro-estructural para caracterizar la alteración. Los frutos del patrón Forner-Alcaide 5 presentaron una menor incidencia de los daños por frío. El almacenamiento a 9°C no comprometió la calidad externa o interna. Dentro del grupo de naranjas, en los últimos años existe una creciente demanda por las naranjas sanguinas para su consumo en fresco. Para evaluar el efecto del patrón se tomaron las variedades 'Moro' y 'Tarocco Rosso' injertadas sobre ocho patrones. La calidad interna se vio afectada por el momento de cosecha, siendo más evidente en 'Moro'. En ambas variedades el patrón afectó a los parámetros de calidad durante la maduración. En 'Moro', se observó una reducción en el color del zumo debido a la degradación de los antocianos, siendo los patrones C-35, Macrophylla y Volkameriana los que mostraron un mayor descenso. Esta degradación se relacionó con los cambio de la temperatura durante el periodo de recolección. En 'Tarocco Rosso' no se evidenció ninguna degradación, lo que sugiere que esta variedad es menos sensible a los cambios de temperatura. En esta variedad Forner-Alcaide 5 y Forner-Alcaide 13 produjeron fruta con mayor contenido en antocianos y azúcares. Además se llevó a cabo el estudio de la aptitud a la frigoconservación de las variedades de sanguinas 'Tarocco Rosso' y 'Sanguinelli'. Mientras que la calidad interna no se vio afectada por el almacenamiento (1°C, 5°C y 9°C) durante 45 días, la fruta presentó síntomas de daños por frío a 1°C. 'Sanguinelli' presentó mayor incidencia que 'Tarocco Rosso'. Estas sanguinas se pueden almacenar entre 5 y 9°C / [CA] La citricultura s'enfronta constantment a escenaris ambientals canviants que provoquen diferents estressos biòtics i abiòtics. El patró sobre el qual s'empelta una varietat específica és una important eina per a millorar la seua adaptabilitat agronòmica en cada àrea de cultiu. En la present Tesi s'ha dut a terme l'estudi de l'efecte del patró sobre la qualitat físic-química i nutricional de la fruita en varietats de gran interés comercial, mandarines 'Clemenules' i 'Tango' i, taronges sanguines 'Tarocco Rosso' i 'Moro'. En 'Clemenules' es va dur a terme l'avaluació de la qualitat de la fruita d'arbres empeltats sobre huit patrons en tres moments de collita, en dues campanyes. Entre els patrons avaluats, Forner-Alcaide 13 i C-35 van destacar per avançar el canvi de color. D'altra banda Forner-Alcaide V17 va destacar per mantindre nivells òptims d'acidesa fins al final de la campanya i va presentar el major contingut en vitamina C, flavonoides, glucosa i fructosa. Carrizo Citrange també va induir altes concentracions de sacarosa i vitamina C en la fruita. 'Tango' és una mandarina de recent introducció en l'àrea mediterrània amb gran interés pel seu període de recol·lecció que comença quan finalitza el de les clementines. En la present Tesi es van estudiar els canvis en la qualitat físic-química, nutricional i sensorial de la mandarina Tango empeltada sobre dos patrons (Carrizo Citrange i Forner-Alcaide 5) durant el període de collita en les dues àrees principals de producció d'Andalusia. La qualitat de la fruita es va veure influenciada per la localització, la qual cosa es va relacionar amb la composició de la textura del sòl. En totes dues localitzacions, Forner-Alcaide 5 va ser el patró que va induir major contingut en acidesa, sòlids solubles totals, sacarosa, vitamina C i àcid cítric en la fruita. Les determinacions físic-químiques i l'avaluació sensorial van permetre establir el moment òptim de recol·lecció depenent de les diferents condicions estudiades. També s'ha inclòs un estudi del comportament postcollita d'aquesta varietat, ja que no existien dades en les nostres condicions de cultiu. La mandarina 'Tango' va presentar símptomes externs de danys per fred a partir dels 20 dies emmagatzemada a 1°C i 5°C. Es va realitzar un estudi micro-estructural per a caracteritzar l'alteració provocada per les baixes temperatures. Els fruits del patró Forner-Alcaide 5 van presentar una menor incidència dels danys per fred. L'emmagatzematge a 9°C no va comprometre la qualitat externa o interna d'aquesta varietat. Dins del grup de taronges, en els últims anys existeix una creixent demanda per les taronges sanguines pel seu consum en fresc. Per a avaluar l'efecte del patró sobre sanguines es van prendre dues varietats, 'Moro' i 'Tarocco Rosso' empeltades sobre huit patrons. La qualitat interna es va veure influenciada pel moment de collita, la qual cosa va ser més evident en la varietat 'Moro'. En totes dues varietats el patró va afectar els canvis en els paràmetres de qualitat estudiats. En 'Moro', es va observar una reducció en el color del suc degut a la degradació del antocians. Aquesta degradació es va relacionar amb el canvi de la temperatura experimentada durant el període de recol·lecció. 'Tarocco Rosso' és menys sensible als canvis de temperatura. En aquesta varietat els patrons Forner-Alcaide 5 i Forner-Alcaide 13 van produir la fruita amb major contingut en antocianos i sucres. A mes s'aporta l'estudi de l'aptitud a la frigoconservació en les sanguines 'Tarocco Rosso' i 'Sanguinelli'. Mentre que la qualitat interna no es va veure afectada per l'emmagatzematge a cap de les temperatures assajades (1°C, 5°C i 9°C) durant 45 dies, la fruita va presentar símptomes de danys per fred a 1°C. `Sanguinelli' va presentar major incidència que 'Tarocco Rosso'. La fruita es pot emmagatzemar entre 5°C i 9°C durant 30 dies en el cas de 'Sanguinelli' i fins a 45 en e / [EN] Citriculture faces changing environmental scenarios that cause biotic and abiotic stress. The rootstock onto which a specific variety is grafted is an important tool to help to improve its agronomic adaptability to each crop area. The present Thesis was carried out to study the effect of rootstock on physico-chemical and nutritional fruit quality in some varieties of commercial interest today: 'Clemenules' and 'Tango' mandarins, and 'Tarocco Rosso' and 'Moro' blood oranges. In 'Clemenules', the fruit of the trees grafted into eight rootstocks at three harvest times was evaluated by performing studies during two seasons. Forner-Alcaide 13 and C-35 Citrange stood out for their earlier color change, which is very interesting for this variety, in which early harvesting is a relevant aspect from the commercial point of view. Forner-Alcaide V17 stood out for maintaining optimum acidity levels until the season ended and presented the highest contents in vitamin C, flavonoids, glucose and fructose. Carrizo Citrange brought about high concentrations of sucrose and vitamin C in fruit. 'Tango' is a mandarin variety that has been recently introduced into the Mediterranean Region. Its harvest time is very interesting because it starts when that of clementines ends. The present Thesis studies changes in the physico-chemical, nutritional and sensorial quality of 'Tango' fruit grafted onto two rootstocks (Carrizo Citrange and Forner-Alcaide 5) during the harvest period in the two main production areas in Andalusia. The results revealed that fruit quality during harvest was influenced by the location, which was particularly related to soil texture composition. In both areas, Forner-Alcaide 5 was the rootstock that induced higher acidity content, and more total soluble solids, sucrose, vitamin C and citric acid in fruit. The physico-chemical determinations, along with the sensorial evaluation, allowed the optimum harvest time to be established depending on the different studied conditions. This Thesis also includes a study about this variety's postharvest behavior as no data are available for our crop conditions. The 'Tango' mandarin presented outer chilling injury symptoms after being stored for 20 days at 1°C and 5°C. A microstructural study was done to characterize the alteration caused by low temperatures. The Forner-Alcaide 5 rootstock fruit showed a lower chilling injury incidence. Storage at 9°C did not compromise quality fruit. Among oranges, demand for blood oranges to be eaten fresh has grown in recent years, basically due to their high content in anthocyanins and their positive effect for human health. To assess the effect that rootstock had on blood oranges, two varieties were taken, 'Moro' and 'Tarocco Rosso', grafted onto eight rootstocks. Internal quality was strongly influenced by harvest time, which was more evident for 'Moro'. In both varieties, rootstock affected changes in the quality parameter studied. In 'Moro', juice color faded as anthocyanins degraded, and rootstocks C-35 Citrange, Macrophylla and Volkameriana showed the most marked reduction. Such anthocyanin degradation was related to the change in temperature that took place during the harvest period. In 'Tarocco Rosso', anthocyanins did not undergo degradation, which suggests that this variety is less sensitive to changes in temperature. In this variety, rootstocks Forner-Alcaide 5 and Forner-Alcaide 13 gave fruit with a higher content of anthocyanins and sugars. This Thesis also includes a study of the suitability of cold storage of two blood orange varieties: 'Tarocco Rosso' and 'Sanguinelli'. Although storage at any tested temperature (1°C, 5°C and 9°C) did not affect internal quality for 45 days, fruit displayed chilling injury symptoms at 1°C, with a higher incidence for 'Sanguinelli' than for 'Tarocco Rosso'. Fruit can be stored between 5°C and 9°C for 30 days for 'Sanguinelli' and for up to 45 days with 'Tarocco Rosso'. / This study has been supported by Instituto Valenciano de Investigaciones Agrarias and co-financed by FEDER and European Social Fund. The authors thank Anecoop S. Coop. and Frutaria Agricultura, S.L for supplying the fruit herein used and its technical support. / Morales Alfaro, J. (2021). Effect of Rootstock on the Fruit Quality of Mandarins "Clemenules" and "Tango", and Blood Oranges "Tarocco Rosso" and "Moro" [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/165858 / Compendio
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Actions of lignocellulolytic enzymes on Abies grandis(grand fir) wood for application in biofuel production

Cherdchim, Banyat 27 October 2010 (has links)
No description available.

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