• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 79
  • 38
  • 12
  • 11
  • 5
  • 3
  • 1
  • 1
  • 1
  • Tagged with
  • 168
  • 56
  • 26
  • 17
  • 17
  • 17
  • 14
  • 14
  • 14
  • 13
  • 11
  • 11
  • 11
  • 10
  • 10
  • 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.
141

Estudos anatômicos e fisiológicos de frutos de caquizeiro (Diospyros kaki L.) quanto ao acúmulo de taninos e aos processos de destanização / Anatomical and physiological studies of persimmon fruits (Diospyros kaki L.) on the tannin accumulation and deastringency processes

Tessmer, Magda Andréia 25 April 2014 (has links)
O presente trabalho visou analisar comparativamente as alterações fisiológicas e estruturais de caquis adstringentes (PVA) e não adstringentes (PCNA) desde o início do desenvolvimento até a maturação avançada. Além disso, na pós-colheita, foram realizados tratamentos de destanização e testadas diferentes condições de armazenamento para \"Giombo\". Este trabalho está sendo apresentado em seis capítulos, sendo que os últimos cinco capítulos referem-se aos experimentos realizados entre 2010 a 2013. No capítulo 2 é apresentado o desenvolvimento de caquis \"Giombo\" (PVA) e \"Fuyu\"(PCNA). Foi possível observar que a diferenciação das células taníferas e o processo de acúmulo de taninos no vacúolo não variou entre as cultivares, porém houve diferença significativa em relação à densidade de células taníferas e aos teores de taninos solúveis. O capítulo 3 apresenta o estudo comparativo de sete estádios de maturação de caquis \"Giombo\" e \"Rojo Brillante\"(PVA) e \"Fuyu\" e \"Hana Fuyu\" (PCNA). A redução da firmeza do mesocarpo de caquis de ambos os grupos está relacionada ao avanço da maturação e não à perda natural da adstringência. A capacidade antioxidante e o teor de sólidos solúveis em caquis dos dois grupos indicam que pode haver relação com a perda natural da adstringência, pois houve decréscimo somente nas cultivares PVA durante a maturação. Os taninos delimitados às células taníferas no teste com vanilina clorídrica, e o conteúdo do vacúolo com aspecto alveolar observado ao Cryo-SEM podem estar relacionados à polimerização dos taninos durante o amadurecimento dos frutos. No experimento descrito no capítulo 4, caquis \"Giombo\" de fim e início de safra foram submetidos a diferentes tempos de exposição ao etanol (1,70 mL Kg-1). No fim da safra os frutos obtiveram índice de adstringência e teores de taninos solúveis adequados para consumo em 24 horas e, no início da safra, em 36 horas. O capítulo 5 discute a influência das pectinas na remoção da adstringência de caquis \"Giombo\" sob o armazenamento refrigerado a 5?C. Os resultados indicaram que não houve interação das pectinas com os taninos solúveis na remoção da adstringência, pois mesmo com a redução da firmeza de polpa e aumento da solubilização das pectinas, o índice de adstringência e o teor de taninos solúveis permaneceram elevados nos frutos não destanizados. No capítulo 6 é apresentada a influência das temperaturas (1, 5 e 10?C) de armazenamento na qualidade de caquis \"Giombo\" destanizados tratados ou não com 1-MCP. A qualidade foi melhor preservada quando os frutos foram destanizados e tratados com 1-MCP e armazenados a 1ºC por até 35 dias. Os frutos que foram apenas destanizados tiveram a estrutura celular do mesocarpo e a firmeza mais alteradas em todas as temperaturas analisadas. Provavelmente, a temperatura de 5ºC torna os frutos mais susceptíveis a danos por frio com redução drástica da firmeza e alterações estruturais. / This study purpose was the comparison between the physiological and structural changes of astringent persimmons (PVA) and non-astringent (PCNA) from the start of development to advanced maturation. Furthermore, postharvest treatments of deastringency were made and tested for different storage conditions at \"Giombo\". This work is presented in six Chapters, and the last five chapters refer to experiments conducted between 2010 and 2013. Chapter 2 describes the development of persimmons \"Giombo\" (PVA) and \"Fuyu\" (PCNA). It was observed that the differentiation of tannin cells and the accumulation process of tannin in vacuole did not vary among cultivars, but there was a significant difference in the density of tannin cells and soluble tannins. Chapter 3 presents the comparative study of seven stages of ripening persimmons \"Giombo\" and \"Rojo Brillante\" (PVA), and \"Fuyu\" and \"Hana Fuyu\" (PCNA). Reduction of mesocarp firmness of both groups of persimmons is related to maturation advance and not due to natural loss of astringency. Antioxidant capacity and total soluble solids of persimmons from both groups indicate a possible relation with the natural loss of astringency, once only PVA cultivars showed astringency decrease during ripening. The tannins delimited in tannin cells for the test with vanillin hydrochloric, and the contents of the vacuole with alveolus aspect observed by Cryo-SEM may be related to tannin polymerization during fruit ripening. In the experiment described in Chapter 4, persimmons \"Giombo\" from late and early harvest were submitted to different periods of exposure to ethanol (1.70 mL kg-1). Fruits obtained at late harvest presented index astringency and soluble tannin content suitable for consumption within 24 hours, while early harvest in 36 hours. Chapter 5 regards to the influence of pectins in astringency removal of persimmons \"Giombo\" under cold storage at 5?C. Results indicated no interaction of pectins with soluble tannins astringency removal, because even with the reduction of flesh firmness and increased solubilization of pectins, the index of astringency and soluble tannins remained high in fruits not deastringenced. The influence of temperature (1, 5 and 10?C) storage on the quality of persimmons \"Giombo\" treated or not with 1-MCP is presented in Chapter 6. Better quality was observed when the fruits were deastringenced, treated with 1-MCP and stored at 1°C for up to 35 days. Fruits that had been only deastringenced had bigger changes on their mesocarp cellular structure and firmness at all temperatures experimented. The temperature of 5°C may be responsible for making fruitsmore susceptible to chilling injury with structural changes and a drastic reduction of the firmness.
142

Effects of replacing maized meal with a low tannin white sorghum meal, macia on productivity of ross 308 broiler chickens

Manyelo, Tlou Grace January 2018 (has links)
Thesis (M. Sc. Agriculture (Animal Production)) -- University of Limpopo, 2018 / Two experiments were conducted to determine the effect of replacing maize meal with a low tannin sorghum meal (Macia) on productivity, gut morphology, carcass characteristics and bone morphometrics of Ross 308 broiler chickens aged one to 42 days. In each experiment, a total of 160 Ross 308 broiler chickens were assigned to a complete randomized design with 5 treatments, replicated 4 times with 8 chickens per replicate. Five diets were formulated to contain sorghum replacement levels at 0, 25, 50, 75 and 100% to meet the nutrient requirements of Ross 308 broiler chickens. Data was analysed using statistical analysis of variance. The first experiment determined the effect of replacing maize meal with a low tannin white sorghum meal on productivity and gut morphology of unsexed Ross 308 broiler chickens aged 1 to 21 days. Feed intake, growth rate, feed conversion ratio, live weight, N-retention, caecum and large intestine digesta pH, large intestine lengths, crop, gizzard, caecum and large intestine weights, gut intestinal villi height, crypt depth and villi height to crypt depth ratio of unsexed Ross 308 broiler chickens were not affected (P>0.05) by the treatment effects. However, replacement of maize meal with sorghum meal improved (P<0.05) metabolisable energy intake and small intestine digesta pH values. It was concluded that maize meal can be replaced by a low tannin white sorghum meal in the diet without adverse effects on unsexed Ross 308 broiler chickens aged one to 21 days. The second experiment determined the effect of replacing maize meal with sorghum meal on productivity, gut morphology, carcass characteristics and bone morphometrics of Ross 308 male broiler chickens aged 22 to 42 days. Replacing maize meal with sorghum meal had no effect (P>0.05) on feed intake, feed conversion ratio (FCR), live weight and nitrogen retention (N-retention) of male Ross 308 broiler chickens aged 22 to 42 days. Replacing maize meal with sorghum meal improved (P<0.05) ME intake and growth rate of the chickens. Caecum and large intestine digesta pH, GIT, caecum and large intestine lengths, small intestine, caecum and large intestine weights, gut intestinal villi height, crypt depth and villi height to crypt depth ratio, drumstick, thigh and wing weights, drumstick, thigh and wing colour, meat sensory evaluation, meat pH and bone morphometrics of male Ross 308 broiler chickens were not affected (P>0.05) by replacement of maize meal with sorghum vii meal. It was concluded that maize meal can be replaced by a low tannin white sorghum meal at 25, 50, 75 and 100% levels without causing adverse effects on productivity and carcass characteristics of male broiler chickens aged 22 to 42 days. Key words: Low tannin sorghum meal, Maize meal, Broiler chickens, Growth rate, Carcass characteristics. / National Research Foundation (NRF)
143

Caractérisation et valorisation de bioressources végétales pour le prétraitement d'effluents par coagulation-floculation / Characterization and valorisation of plant bioresources for pretreatment of effluents by coagulation flocculation

Bouaouine, Omar 18 October 2018 (has links)
Les biofloculants sont une alternative durable aux sels métalliques et aux polymères de synthèse pour le traitement des eaux par coagulation floculation (CF). La littérature a surtout décrit les paramètres optimaux pour l’application des matériaux biosourcés en CF. En étudiant deux exemples, Opuntia ficus indica, connu pour ses propriétés coagulantes et les margines, un déchet peu valorisable issu de la trituration des olives, nous proposons une méthodologie pour déterminer la nature des molécules actives et appréhender le mécanisme de CF impliqué. L’expérimentation a été menée sur un effluent synthétique à base de kaolinite. Les conditions optimales de CF, ont été déterminées par la méthode classique du jar test couplée à de la zétamètrie et de la microscopie. Pour les margines, les conditions optimales sont obtenues pour un pH de 11 et une dose d’extrait de 62.5 mg L-1. La couleur des margines impose néanmoins l’utilisation de 50 mg L-1 de coagulant métallique (Al2 (SO4)3). Nous avons ensuite basé notre étude sur une approche comparative de différentes fractions hydrosolubles en fonction du pH, dans les deux cas les molécules actives ont montré une solubilité maximale au pH optimal de CF. La détermination des pKa, la réalisation de dosages colorimétriques (protéine, sucres, polyphénols, tanin) et l’analyse infrarouge du matériel brut a permis d’envisager les familles de molécules impliquées (dans les deux cas, les tanins / flavonoïdes et les sucres). Des expériences de CF effectuées après digestions enzymatiques permet de confirmer l’identification des molécules impliquées dans le mécanisme. Ainsi la CF se fait par adsorption et pontage pour les deux matériaux. La faisabilité du traitement d’eaux résiduaires (industrie textile, lixiviat de décharge) par des extraits d’Opuntia ficus indica a été validé. Les tanins/ flavonoïdes et particulièrement la quercétine pour le cactus, s’adsorbent sur les colloïdes de l’effluent puis un polymère d’amidon (cactus) ou de cellulose (margine) permet la floculation par adsorption et pontage. / Biofloculants represent a sustainable alternative to metal salts and to synthetic polymers for water treatment by coagulation flocculation (CF). The optimal parameters of biomatrerials applicated in CF were mainly described by literature data. Opuntia ficus indica, known for its flocculating properties and olive mill waste (OMW), which its reuse not deeply examined, were chosen in our study. A methodology was proposed in order to determine the nature of the active molecules and to better understand the involving mechanism in CF. The experiment was conducted on a synthetic water based on kaolinite. The optimal conditions of CF were determined by jar test coupled with zeta potential and microscopy. For OMW, the optimum conditions are obtained for a pH of 11 and an extract dose of 62.5 mg L-1. The removal of OMW colors requires the use of 50 mg L-1 of a metal coagulant (Al2 (SO4)3). Afterwards, our study was based on a comparative approach of different water-soluble fractions as function of pH. The active molecules showed a maximum solubility at the optimal pH of CF, in both cases. The characterization of the raw materials by pKa, colorimetric assays (proteins, sugars, polyphenols and tannins) and the infrared analysis allowed to determine the molecules involved in CF (In both cases, tannins / flavonoids and sugars). CF experiments performed after enzymatic approach confirm the identification of molecules involved in the mechanism and suggest that the two materials operate through an adsorption and bridging mechanism. The efficiency of wastewater treatment (textile industry, landfill leachate) by Opuntia ficus indica extracts has been validated. Tannins/ flavonoids and especially quercetin for cactus promotes a colloidal material destabilization (coagulant) through anion exchanges and bridges; otherwise, the starch (cactus) or cellulose (OMW) forms a large cross-linked polymeric network responsible for bridging.
144

Ablauf und Beeinflussungsmöglichkeiten der Proteolyse während der Silierung von Weidelgras und Luzerne

Roscher, Simone 22 February 2018 (has links)
Tannine gehören zu den phenolhaltigen Verbindungen und galten in der Tierernährung bisher als sekundäre unerwünschte Pflanzeninhaltsstoffe. Sie werden in der Regel in zwei Hauptgruppen eingeteilt: kondensierte und hydrolisierbare Tannine. Im Mittelpunkt der vorliegenden Untersuchungen stand die Quantifizierung der Reduzierung der Proteolyse während der Silierung in Folge der Zulage von tanninhaltigen Pflanzenextrakten unterschiedlicher Herkunft zum Siliergut. Zu diesem Zweck wurden zunächst in Silierversuchen zwei tanninhaltige Pflanzenextrakte unterschiedlicher botanischer Herkunft (Mimosa und Quebracho) alleine sowie in Kombination mit Silierzusätzen dem Ausgangsmaterial am Beispiel Weidelgras (Lolium perenne L.) zugesetzt. Folgend wurden die Effekte unterschiedlicher Konzentrationen der beiden tanninhaltigen Pflanzenextrakte sowie die Effekte bei unterschiedlichen TM-Gehalten des Siliergutes auf den Umfang der Proteolyse am Beispiel der Luzerne (Medicago sativa L.) geprüft. In den Versuchen konnte gezeigt werden, dass die Tannine einen deutlichen Einfluss auf die Proteolyse während der Silierung insbesondere in den ersten Tagen hatten. Die Beurteilung der Effekte der Zulage von tanninhaltigen Pflanzenextrakten basierte unter anderem auf Veränderungen der Parameter der Rohproteinfraktionierung nach dem Cornell Net Carbohydrate and Protein System (CNCPS). Durch den Zusatz von tanninhaltigen Pflanzenextrakten konnte der Abbau von schwer- und mittellöslichen Rohproteinfraktionen (Fraktionen B1-B3) zur leichtlöslichen Rohproteinfraktion (Fraktion A) signifikant minimiert werden, parallel stieg der Gehalt der pansenstabilen Rohproteinfraktionen. Die Effekte unterschiedlicher TM-Gehalte in den Silierversuchen mit Luzerne (Medicago sativa L.) zeigten, dass die eingesetzten tanninhaltigen Pflanzenextrakte unabhängig von ihrer botanischen Zusammensetzung in ihrer Wirkung umso höher waren je geringer der TM-Gehalt war. / Tannins belong to phenol compounds and have traditionally been classified as antinutritive substances in animal nutrition. Tannins are usually divided into two groups: hydrolyzed and condensed tannins. The present study focused on reducing proteolysis during ensilage by supplementing tannin extracts from different botanical sources. Ensilage studies were carried out with Lolium perenne dominated forage and two different tanniniferous extracts (Mimosa and Quebracho) alone as well as in combination with silage additives. In a second study, the effects of different tannin concentrations and two different dry matter levels on proteolysis during ensilage were tested with alfalfa (Medicago sativa L.). The results show that tannin extracts definitely reduce proteolysis during the first days of ensilage. The protein fractionation of the Cornell Net Carbohydrate and Protein System (CNCPS) was used as indicator. Degradations from slightly soluble (B1 – B3) to easily soluble (A) fractions were significantly reduced by the addition of tannin extracts. At the same time, the level of rumen undegradable true protein was increased. The alfalfa study used different dry matter levels showing that by supplementing tannin extracts the wetter the silage was, the clearer the effect on reducing proteolysis.
145

Influence of ripening grape compounds on behavioural responses of birds

Saxton, V. P. January 2004 (has links)
Vineyards in New Zealand suffer bird damage caused by several avian species, including blackbirds and silvereyes. The introduced European Blackbird takes whole grapes which reduces yield. The self-introduced Australasian Silvereye pecks on grapes, leaving them on the vine to be further attacked by fungi and bacteria, and the subsequent off-odours can cause grapes to be refused by the winery or to suffer a price-reduction. Bird control methods remain primitive and largely ineffective during the long ripening period of wine grapes. An ecologically sound method to manage and reduce bird pressure requires deeper understanding of why some birds eat grapes, especially since grapes are not particularly nutritious. This work investigated the extent to which blackbirds and silvereyes are attracted by various compounds in ripening grapes. Since in natural grapes these compounds develop and change simultaneously, I developed an artificial grape in which a single parameter could be investigated. Artificial grapes (and sometimes nectar) were presented on a bird feeder table and the responses of birds to hexose sugars, the aromas 2-3-isobutylmethoxypyrazine and geraniol, tartaric and malic acids, grape tannins, and purple and green colour were recorded on timelapse video and analysed.
146

Untersuchungen zu tanninbindenden Speichelproteinen des Rehs und anderer Wiederkäuer / Investigation of tannin binding salivary proteins of roe deer and other ruminants

Gehrke, Janin January 2002 (has links)
Am Beispiel der Wiederkäuer wurde unter Zuhilfenahme von biochemischen und molekularbiologischen Methoden die Adaptation von Pflanzenfressern (Herbivoren) an pflanzliche Sekundärmetabolite wie z.B. Tannine untersucht. Tannine können in nicht an ihren Verzehr adaptierten Spezies durch ihr Proteinbindungsvermögen die Nahrungsverwertung und damit Wachstum und Gesundheit des Pflanzenfressers beeinträchtigen (antinutritive Wirkung). <br /> Einige Wiederkäuerarten wie z.B. das Reh (Capreolus capreolus) haben in ihrem Nahrungsspektrum viele stark tanninhaltige Pflanzen, leiden aber nicht unter den erwähnten postdigestiven Konsequenzen. Eine Möglichkeit, die antinutritive Wirkung von Tanninen zu neutralisieren, besteht in der Produktion tanninbindender Speichelproteine. <br /> Der Speichel verschiedener Wiederkäuerarten wurde auf das Vorhandensein tanninbindender Proteine untersucht. Diese Arten wurden so ausgewählt, dass alle drei Ernährungstypen (Konzentratselektierer, Intermediärtyp, Gras- und Rauhfutterfresser) in den Vergleich eingeschlossen werden konnten. Als Referenzspezies wurde der Konzentratselektierer Reh herangezogen.<br /> Die Speichelproteine des Rehs und die der Intermediärtypen (Rentier, Rangifer tarandus; Damhirsch, Cervus dama; Moschusochse, Ovibos moschatus) banden ungefähr doppelt so effektiv an hydrolysierbare Tannine (Tanninsäure), wie die der untersuchten Gras- und Rauhfutterfresser (Rind, Bos taurus; und Mufflon, Ovis orientalis musimon). Diese Abstufung zeigte sich auch bei der Untersuchung der Bindung an kondensierte Tannine (Quebracho). Eine Ausnahme stellte Mufflonspeichel dar, dieser band ebenso gut an Quebracho wie die Speichelproteine der anderen Ernährungstypen.<br /> Über eine Aminosäuretotalanalyse konnte festgestellt werden, dass der Speichel einiger untersuchter Wiederkäuerarten prolinreiche Proteine (PRPs) enthielt. Unter Ausnutzung ihrer Trichloressigsäure (TCA)-Löslichkeit wurden diese angereichert und genauer untersucht. Die Analyse der TCA-löslichen Speichelproteine der Konzentratselektierer (Reh, Elch) ergab einen relativen Prolingehalt von über 35 %, während beim Moschusochsen noch 29 % gemessen wurden. In Damhirsch- und Rinderspeichel wurden keine prolinreichen Proteine gefunden.<br /> Für die TCA-löslichen Speichelproteine des Rehs konnte eine hohe Tanninbindungskapazität nachgewiesen werden. Diese banden 24 - 30 x effektiver an Tannine als die TCA-löslichen Speichelproteine des Rindes. Die Tanninbindungskapazitäten der TCA-löslichen Speichelproteine von Moschusochse und Damhirsch waren ebenfalls höher als die des Rindes, aber niedriger als die des Rehs. <br /> Die Kohlenhydrat-Analyse der TCA-löslichen Speichelproteine des Rehs erbrachte, dass es sich bei ihnen um Glykoproteine handelt. Mittels Gelfiltration und zweidimensionaler Polyacrylamidgelektrophorese konnten fünf Proteingruppen mit Molekulargewichten zwischen 15 und 50 kd sowie isoelektrischen Punkten zwischen 4,0 und 8,2 detektiert werden. <br /> Von 15 dieser Proteine konnten die N-terminalen Aminosäuresequenzen ermittelt werden. Ausgehend von diesen Informationen wurden Reh-PRP spezifische mRNAs isoliert und partiell sequenziert. Die meisten dieser Fragmente hatten eine gemeinsame 18 Aminosäuren lange C-terminale Sequenz PPPEEQPEE/QSPDEE/DSPSE. <br /> Die Suche nach Übereinstimmungen der analysierten Sequenzen mit anderen Säugetier-PRPs in der Genbank ergab keine sinnvollen Ähnlichkeiten. Die Ergebnisse können zu Informationen über tanninbindende Proteine anderer Wiederkäuer führen. Die Sequenzinformationen stellen einen Ausgangspunkt bei der Analyse der evolutiven Zusammenhänge der Cerviden dar. / Investigation of tannin binding salivary proteins of roe deer and other ruminants: <br /> In this work the adaptation of herbivores to plant secondary metabolites was investigated with help of biochemical and molecular biological methods. In unadapted species plant secondary metabolites as tannins can reduce food digestibility and thus diminish growth rate and health status (antinutritive action). Tannins act through its astringency, that means the high capacity to bind proteins, other macromolecules and metal ions. Some ruminant species feed on tannin containing plant but do not suffer from the mentioned nutritive consequences. The production of tannin binding proteins is one possible adaptation mechanism to neutralize the effects of the tannins.<br /> Saliva of six different ruminant species was investigated for the presence of tannin binding proteins. All three feeding types (concentrate selector, intermediate type and grass and roughage eater) were included in the comparison. <br /> Salivary proteins from roe deer (Capreolus capreolus, concentrate selector) and from the intermediate feeding types (rein deer, Rangifer tarandus; fallow deer, Cervus dama; musk ox, Ovibos moschatus) bound twice as effective to hydrolysable tannins (tannic acid) as those from the investigated grass and roughage eaters (cattle, Bos taurus; moufflon, Ovis orientalis). This differentiation could also be observed investigating the binding capacities to condensed tannins (quebracho) except for moufflon. Moufflon salivary proteins bound with the same intensity to quebracho as the salivary proteins from the other feeding types.<br /> Proline rich proteins (PRPs) could be accumulated from roe deer, moose and musk ox saliva by use of its solubility properties in 5 % trichloro acetic acid (TCA). Roe deer and moose TCA soluble salivary proteins contained more than 35 %, musk ox proteins 29 % proline. In fallow deer and cattle saliva PRPs could not be detected.<br /> A tannin binding assay demonstrated for the TCA soluble salivary proteins from roe deer, musk ox and fallow deer but not from cattle, that they are able to bind tannins. Roe deer salivary proteins bound 24 to 30 more effective to tannins as cattle proteins. Tannin binding capacity of the proteins from musk ox and fallow deer saliva was higher as those from cattle but lower as those from roe deer.<br /> For further analysis of ruminant tannin binding proteins we chose roe deer as reference species. Carbohydrate analysis of TCA soluble proteins from roe deer saliva showed that they were glycoproteins. With help of gel filtration and two dimensional polyacrylamid gel electrophoresis five proteins groups with molecular weights from 15 to 50 kd and isoelectric points from 4.0 to 8.2 could be detected.<br /> N-terminal amino acid sequences of 15 of the roe deer salivary TCA soluble proteins were determined by Edmann degradation. This information led to partially sequenced roe deer PRP specific cDNA. An 18 amino acid long C-terminal sequence was common in most of the clones. The obtained roe deer PRP sequences did not match with known mammalian PRP sequences from data banks. <br /> The finding in this work can lead to information about salivary tannin binding proteins in other ruminants. The sequence information represent a starting-point for the investigation of cervid evolution.
147

Aplicação de polieletrólitos para a separação de metais em efluentes da suinocultura / Polyelectrolytes aplication of metal separation in wastewater of swine poultry

Steinmetz, Ricardo Luis Radis 09 February 2007 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The increase on swine livestock activity demands profitable resources and environmentally sustainable for the treatment, disposal and the residual water reuse. Due to the high wastewater volume, they have a huge pollutant load, among them several metals, that can cause environment impact. This work presents an evaluation of phase separation for Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sr and Zn removal in swine manure through the coagulation and flocculation whit synthetic and natural polyelectrolyte. For this proposal, the metals were monitored in the effluent and solid-liquid separation assays (Jar Test) with poliphenolic polymer (Tannin) and polyacrilamide (PAM) applied at different concentration. The optimization was accomplished by the application of factorial design. For the metal determination three mixtures of reagents had been evaluated (nitric acid + perchloric acid, sulfuric acid + hydrogen peroxide and nitric acid + hydrogen peroxide) for samples decomposition of swine manure, the best result for recovery and correlation was found to nitric acid and hydrogen peroxide mixture. After the separation of the liquid fraction, reductions between 68 and 99% were found out in the investigated metal concentrations. Besides that, reductions over 90% for chemical oxygen demand were also observed. A significant influence in turbidity removal only by the tannin utilization was found out. However the PAM application improved directly the flocks generation and influenced the sludge volume reduction. The polyelectrolyte use provided the reduction of metal concentration in the wastewater to adjust to the brazilian legislation for discharging into water bodies or for reuse in irrigation systems. The sludge produced after the solid-liquid separation also showed concentrations of inorganic constituents below of maximum limits claimed by legislation for the agricultural use. / O crescimento da atividade suinícola demanda recursos rentáveis e ambientalmente sustentáveis para o tratamento, disposição e reuso de suas águas residuárias. Além de seu grande volume de efluentes, estes possuem alta carga de poluentes, entre eles diversos metais, danosos ao meio ambiente. Este trabalho apresenta uma avaliação da separação de fases para remoção de Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sr e Zn em dejetos de suínos através de coagulação e floculação com polieletrólitos, sintético e natural. Para isso, monitoraram-se os metais no efluente e foram realizados ensaios de separação sólido-líquido (Teste de Jarro) com aplicação de polímero polifenólico natural (tanino) e poliacrilamida (PAM). As otimizações foram realizadas aplicando planejamento fatorial. Para as determinações de metais foram avaliadas decomposições de amostras de dejeto de suíno empregando três misturas de reagentes (ácido nítrico + ácido perclórico, ácido sulfúrico + peróxido de hidrogênio, ácido nítrico + peróxido de hidrogênio), onde os resultados de recuperação e correlação permitiram a escolha da mistura ácido nítrico e peróxido de hidrogênio. Foram observadas reduções entre 68% e 99% nas concentrações dos metais investigados após separação da fração líquida, além de reduções superiores 90% para a demanda química de oxigênio e superiores a 98% para a turbidez. Foi constatada interação na remoção de turbidez somente ao emprego de Tanino, porém a aplicação de PAM melhorou diretamente a formação dos flocos e sedimentação do lodo. Os polieletrólitos proporcionaram a redução da concentração de metais na água residuária, auxiliando no enquadramento das concentrações dos metais investigados à legislação, para descarte em corpos de água receptores ou ao reuso em sistemas de irrigação. O lodo produzido após a separação sólido-líquido apresentou concentrações de constituintes inorgânicos abaixo dos limites máximos exigidos pela legislação para o uso agrícola.
148

Tanino da ac?cia negra como inibidor da corros?o de a?o API5L X65 em meio ?cido

Bettanin, Viviane 29 August 2018 (has links)
Submitted by PPG Engenharia e Tecnologia de Materiais (engenharia.pg.materiais@pucrs.br) on 2018-11-16T17:04:36Z No. of bitstreams: 1 Disserta??o homologa??o Viviane Bettanin 14.11.2018.pdf: 3436850 bytes, checksum: 12199a52b8023657a598a8254ca85c0f (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-11-19T13:58:36Z (GMT) No. of bitstreams: 1 Disserta??o homologa??o Viviane Bettanin 14.11.2018.pdf: 3436850 bytes, checksum: 12199a52b8023657a598a8254ca85c0f (MD5) / Made available in DSpace on 2018-11-19T14:07:36Z (GMT). No. of bitstreams: 1 Disserta??o homologa??o Viviane Bettanin 14.11.2018.pdf: 3436850 bytes, checksum: 12199a52b8023657a598a8254ca85c0f (MD5) Previous issue date: 2018-08-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / In order to reduce the environmental impacts caused by chemical harmful to the environmental and to human health, the development of natural substances that are able to substitute these dangerous components have been increased. Tannins are a group of natural poliphenolic components extracted from plants that could be used as corrosion inhibitors. This study investigates the utilization of two bark of black wattles (Acacia mearnsii) as corrosion inhibitors, Weibull and Macrospec, in acidic medium and in atmospheric environment and in aqueous CO2 rich medium under high pressure. API 5L X65 steel samples were exposed to a corrosive medium (0.1 M HCl) with different tannin concentrations. The best results were duplicate to an environmental with CO2 saturated water at 15 MPa and 50?C. In order to characterize the specimens scanning electron microscopy by gun field emission, energy dispersive spectroscopy, X ray diffraction, mass loss tests and potenciodynamic polarization tests were used. The results indicated that both tannins, at atmospheric pressure and 0.1 M HCl corrosive environment have similar performance as corrosion inhibitors, and the higher dosage tested (12 g/L) exhibited the best efficiency. However, when the tannins were tested in environment with presence of CO2 under high pressure (15 MPa) and 50?C the results were different, and only Macrospec tannin had an inhibitory action under the conditions tested. / Visando diminuir os impactos ambientais causados por subst?ncias qu?micas nocivas ao meio ambiente e ? sa?de humana, a procura por substitutos naturais destes compostos em diversas aplica??es vem sendo intensificada. Taninos compreendem uma classe de compostos polifen?licos naturais extra?dos de plantas, podendo ser usados como inibidores de corros?o em meio aquoso. Neste estudo avaliou-se a utiliza??o de dois taninos vegetais da ac?cia negra (Acacia mearnsii), Weibull (em p?) e Macrospec (l?quido), como inibidores de corros?o em meios ?cidos em ambiente atmosf?rico e em ambiente com a presen?a de CO2 a alta press?o. Corpos de prova de a?o API5L X65 foram expostos a meio acidificado com HCl 0,1 M com diferentes concentra??es de taninos e o melhor resultado no que se refere ? concentra??o do tanino para a inibi??o de corros?o foi replicado para um meio com ?gua saturada com CO2 a 15 MPa e 50?C. Para caracteriza??o foram realizadas as an?lises de microscopia eletr?nica de varredura, difra??o de raios X, medidas eletroqu?micas de polariza??o potenciodin?mica, e testes de perda de massa. Os resultados indicaram que ambos os taninos, em meio de HCl 0,1 M e press?o atmosf?rica, apresentaram desempenho similar no que diz respeito aos efeitos de inibi??o da corros?o e a maior dosagem utilizada (12 g/L) foi a que apresentou melhor efici?ncia de inibi??o. Por?m, quando testados em meio de ?gua saturada com CO2 a 50?C e 15 MPa o comportamento dos taninos foi distinto, sendo que apenas o tanino Macrospec teve a??o inibit?ria nas condi??es testadas.
149

APROVEITAMENTO DA CASCA DE ARROZ PARA FABRICAÇÃO DE CHAPAS AGLOMERADAS / UTILIZATION OF RICE HUSK FOR MANUFACTURE OF PARTICLEBOARD

Souza, Joel Telles de 05 June 2012 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Rice husk, waste produced by processing of rice, has become a problem of environmental, economic and public health. As a result, this research aims to explore the potential of these underutilized resources in Brazil in the development of particleboard glued with tannin-formaldehyde. Therefore, panels were manufactured with rice husk compacted at different density (0.65, 0.95 and 1.15 g/ cm³), levels of adhesives (7, 10 and 13%) and particles types (natural and processed), totaling 54 panels. The physical tests performed were moisture content, density, water absorption and thickness swelling and mechanical were static bending, screw withdrawal and internal bond. In order to complement the study, there were conducted biological tests for resistance to decay fungi Trametes versicolor and Gloephyllum trabeum. The results were analysed by for simple correlation and regression. In general, the use of rice hulls provided a reduction in strength of the compared to those made with wood particles. All particleboard were below the minimum standards in physical and mechanical tests; only the panels with 13% resin provided minimum values required by market standards regarding dimensional stability. The best performance of the panels developed in this work was found in biological tests. According to the criteria of the american standard, all treatments were classified as resistant to the fungus Trametes versicolor to white rot. In fungus Gloeophyllum trabeum (brown rot), most treatments were classified as moderately resistant. Therefore, this raw material, has proven to be an alternative with great potential for making panels for greater resistance to decay fungi. / A casca de arroz, resíduo produzido pelo beneficiamento deste grão, tem se tornado um problema de ordem ambiental, econômica e de saúde pública. Em vista disso, a presente investigação tem como objetivo avaliar o aproveitamento deste resíduo para a fabricação de chapas aglomeradas, coladas com tanino-formaldeído. Para tanto, foram utilizadas casca de arroz na forma natural ou processada em moinho de martelo, compactadas a diferentes massas específicas (0,65, 0,95 e 1,15 g/cm³) e aplicando-se teores de adesivos de 7, 10 e 13% (com base no peso seco das partículas), totalizando 54 chapas. Os ensaios físicos realizados foram teor de umidade, massa específica, absorção d água e inchamento em espessura; e mecânicos, de flexão estática, arrancamento de parafuso e ligação interna. Para complementar o estudo, realizou-se ensaios biológicos para determinar a resistência ao ataque de fungos apodrecedores Trametes versicolor e Gloephyllum trabeum. Os resultados foram submetidos ao teste de correlação simples de Pearson e analisados por regressão. De modo geral, a utilização da casca de arroz proporcionou uma redução na resistência física e mecânica das chapas, em relação as produzidas com partículas de madeira encontradas na literatura. Todos os tratamentos ficaram abaixo dos valores mínimos requeridos pelas normas de comercialização para os ensaios físicos e mecânicos, somente os de 13% de adesivo apresentaram resistência satisfatória quanto à estabilidade dimensional. O melhor desempenho foi verificado nos testes biológicos. De acordo com os requisitos da norma americana, todos os tratamentos foram classificados como resistentes ao fungo Trametes versicolor para podridão branca. No fungo Gloeophyllum trabeum (podridão parda), a maioria dos tratamentos foram classificados como moderadamente resistente. Portanto, esta matéria-prima revelouse uma alternativa de elevado potencial para a manufatura de chapas de maior resistência a fungos apodrecedores.
150

Remoção de antinutrientes de fontes protéicas vegetais para alimentação do jundiá (Rhamdia quelen) / Removal of antinutrients in plant protein sources for jundiá (Rhamdia quelen) feeding

Bergamin, Giovani Taffarel 27 February 2013 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / With the expanding aquaculture activity, high quality ingredients for fish feeding are required. In order to prevent the risk of depending on fish meal, research institutions and the industry itself, have conducted studies to reduce the dependence of fish meal increasing the nutritional value of alternative feedstuffs. The objective of the study was to evaluate different methods of inactivation of antinutritional compounds on nutrient availability of plant protein sources for catfish. The work was divided into three parts: removal of antinutrients, growth trial, and digestibility experiment. In the first part, different chemical treatments for removal of phytic acid, total phenols and tannins in canola, soybean and sunflower meals were tested. The treatments were: acidified water (pH 1.0); ethanol PA + methanol PA; acidified ethanol PA (pH 1.0); ethanol + water PA 70:30 pH 1.0; acidified water + ethanol PA, used separatelly. Washing with pH 1,0 water, followed by washing in ethanol PA was the best alternative for removal of phytic acid, phenols and tannins of canola, sunflower and soybean meal. In the growth experiment were evaluated growth performance, body composition, biochemical parameters, enzymatic profile and intestinal morphometry of juvenile catfish fed with plant ingredients, treated or not treated for removal of antinutrients. Treatments were: control diet, with fish meal as only protein source (CON); replacement of 30% of fishmeal protein by untreated soybean meal (SNT), canola meal (CNT) and sunflower meal (GNT) or the same ingredients submitted to treatment: (ST), (CT) and (GT) (soybean, canola and sunflower, respectively). The treatment is effective, with the exception of phytic acid in soybean meal. ST and CT can replace 30% of fish meal protein, without affecting the growth of animals. There is no difference in the performance of fish fed CT compared to CNT, and GT compared to GNT. For soybean meal, there is improvement in the nutritional value after treatment. The biochemical changes do not appear to be linked to the antinutritional factors. There is no interference of the treatment on the enzymatic activity of silver catfish. Fish fed with untreated ingredients showed enlargement in the thickness of the muscle layer in the intestinal epithelium. The number of villi is higher in fish fed with treated ingredients. There is an increase in the thickness of the lamina propria of the villi in fish fed with the untreated ingredients. In the digestibility experiment, were evaluated the apparent digestibility coefficients (ADCs) of plant ingredients, submitted or not to chemical treatment to remove antinutritional factors in diets for jundiá. The ADC for crude protein was higher in ST, compared to CT and CNT, but did not differ from the others. GNT, GT and CNT showed the lowest ADC for organic matter. The removal of antinutrients do not affect the ADC of crude protein, dry matter and organic matter in soybean and sunflower meal. For canola meal, removing antinutritional factors improve dry matter digestibility. In addition, besides the antinutrients, special care must be taken to concentration or removal of other nutrients when using chemical treatments, otherwise the nutritional value of the ingredient can be affected. / Com a expansão da atividade de aquicultura, surgem também demandas por ingredientes de qualidade para uso em dietas para peixes. Nas últimas décadas, devido à probabilidade de escassez de farinha de peixe, diversas instituições de pesquisa, assim como a própria indústria, têm realizado estudos a fim de reduzir a dependência desta fonte de proteína, através de técnicas para o aumento da qualidade nutricional de ingredientes alternativos à farinha de peixe. Assim, o objetivo do trabalho foi avaliar diferentes métodos de inativação de compostos antinutricionais sobre a disponibilidade de nutrientes de fontes proteicas de origem vegetal para o jundiá. O trabalho foi dividido em três etapas: tratamento dos farelos, experimento de desempenho e experimento de digestibilidade. Na primeira etapa, foi feita a avaliação da eficiência de diferentes tratamentos químicos para remoção de ácido fítico, fenóis totais e taninos totais em farelos de canola, soja e girassol, visando a utilização em dietas para peixes. Os tratamentos foram: água acidificada (pH 1,0); etanol P.A. + metanol P.A. + água; etanol P.A. acidificado (pH 1,0); etanol P.A. + água 70:30 pH 1,0; água acidificada + etanol P.A. utilizados individualmente. O processamento dos farelos através de lavagem com água em pH 1,0, seguido por lavagem em etanol P.A, apresenta comportamento mais uniforme, sendo o mais indicado para a retirada de ácido fítico, fenóis totais e taninos totais dos farelos de canola, girassol e soja. No experimento de crescimento, foram avaliados desempenho zootécnico, composição corporal, parâmetros bioquímicos, perfil enzimático e morfometria intestinal de juvenis de jundiá alimentados com ingredientes vegetais, submetidos ou não a tratamento para remoção de antinutrientes. Os tratamentos foram: dieta controle, à base de farinha de peixe (CON); substituição de 30% da proteína da farinha de peixe por farelos de soja (SNT), canola (CNT) ou girassol (GNT) sem tratamento ou tratados: (ST), (CT) e (GT) (soja, canola e girassol, respectivamente). O tratamento é eficaz na remoção de antinutrientes, com exceção do ácido fítico do farelo de soja. Farelos de soja e canola tratados podem substituir 30% da proteína da farinha de peixe, sem prejudicar o crescimento dos animais. Não há diferença no desempenho de jundiás alimentados com farelo de canola tratado e nãotratado ou girassol tratado e não-tratado. Para farelo de soja, há melhora na qualidade nutricional após tratamento. As alterações bioquímicas não parecem estar ligadas aos fatores antinutricionais presentes. Não há interferência do tratamento sobre a atividade enzimática de jundiás. Peixes alimentados com os farelos não-tratados apresentam camada muscular do epitélio intestinal mais espessa. O número de vilosidades é maior nos peixes alimentados com os farelos tratados. Há aumento na espessura da lamina propria das vilosidades nos peixes alimentados com os farelos não-tratados. No experimento de digestibilidade, foram determinados os coeficientes de digestibilidade aparente dos farelos de canola, girassol e soja, submetidos ou não a tratamento químico para extração de antinutrientes, em dietas para o jundiá. O tratamento para remoção de antinutrientes não afeta os coeficientes de digestibilidade da proteína bruta, matéria seca e matéria orgânica dos farelos de soja e girassol. Para o farelo de canola, a remoção de fatores antinutricionais melhora a digestibilidade da matéria seca. A avaliação de tratamentos para retirada de fatores antinutricionais deve levar em consideração, além da remoção de antinutrientes, a concentração e/ou remoção dos demais nutrientes durante o processo e sua relação com a qualidade nutricional do ingrediente.

Page generated in 0.0644 seconds