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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.
111

Análise cromatografica de biocidas anti-incrustantes em amostras de água de mar e tecido de moluscos / Chromatographic analysis of booster antifouling biocides in seawater samples and molluscs tissue

Lia Gracy Rocha Diniz 02 September 2016 (has links)
A indústria naval é uma das mais importantes para economia e desenvolvimento de um país, no entanto, as diversas atividades desenvolvidas em zonas portuárias contribuem para o impacto ambiental a ambientes costeiros, dentre os vários grupos de micropoluentes orgânicos potencialmente danosos a esses ecossistemas, emergiram nos últimos anos os biocidas anti-incrustantes. Pinturas anti-incrustantes são tratamentos utilizados para minimizar processos corrosivos, diminuindo custos com manutenção, economizando combustíveis e reduzindo a veiculação de espécies não nativas entre ecossistemas costeiros. Neste estudo foi desenvolvido, validado e aplicado um método analítico para determinação dos biocidas anti-incrustantes, clorotalonil, diuron, irgarol e tiram em amostras de água, e tecido biológico em diferentes regiões portuárias da costa brasileira e da Ilha de Gran Canaria -Espanha. / The maritime industry is an important aspect of a countries economy, however, the cumulative activities of port areas has an impact on coastal environments, this can include the addition of harmful micro-organic material. Among the potentially harmful micro-organic material being added to ecosystems, are recently emerged anti-fouling biocidal paints. Anti-fouling paints are used as a treatment to minimize corrosive processes, reduce maintenance costs, save fuel and reduce the transmission of non-native species to coastal ecosystems. This study developed, validated and applied an analytical method for the determination of the anti-fouling biocidal paints, chlorothalonil, diuron, irgarol and tiram in water samples and biological tissue in different port areas of the Brazilian coast and the Gran Canaria Island in Spain.
112

Water Dispersed Epoxy Resin For Surface Coatings

Sen, Evrim 01 December 2003 (has links) (PDF)
In this research water dispersed epoxy varnishes were produced by reacting solid epoxy resin with ethylene diamine (EDA) and maleinized fatty acids of linseed oil. Maleinized fatty acid (MFA) was produced by the maleinization process, in which, fatty acid and maleic anhydride were reacted under nitrogen atmosphere. Maleinization was performed in order to insert hydrophilic groups to the fatty acid chains, which were then inserted to the backbone of the epoxy resin. This was done to give water dispersibility to the hydrophobic epoxy resin. Solid epoxy resin was dissolved in 1,4-dioxane. Ethylene diamine was then added to the solution at 50&deg / C, and stirred for 4 hours. Then the temperature was increased to 80oC and kept for 2 hours. Maleinized fatty acids were then introduced, and the reaction was carried out at 90oC for 10 hours. 1,4-dioxane was used for the removal of the water, which forms as the byproduct. Then the driers were added. The carboxylic groups of the maleinized fatty acid were neutralized by morpholine and the product was dispersed in water. The varnish was applied on test panels and left for air-drying for 24 hours and then baked at 140&deg / C for 5 hours. The free epoxy content was determined by pyridinium-chloride titration and it was seen that all the epoxy groups reacted. Also, produced fatty acid was characterized by FTIR spectroscopy and maleinized fatty acid was characterized by H-NMR and FTIR spectroscopy. Hardness, bending, impact resistance, gloss, and abrasion resistance tests were carried out on hardened varnish specimens. The samples generally showed good mechanical and physical properties. While the baking time was increased the hardness of product increased. Samples showed superior impact resistance, gloss, and flexibility.
113

Μελέτη αποδέσμευσης ιόντων δισθενούς χαλκού σπό σύμπλοκα πολυηλεκτρολυτών με αντίθετα φορτισμένες επιφανειοδραστικές ενώσεις

Οικονόμου, Ευδοκία 22 December 2009 (has links)
Στην παρούσα διατριβή διερευνήθηκαν οι παράμετροι που ελέγχουν τη δέσμευση/αποδέσμευση ιόντων Cu2+ ή/και κατιοντικών επιφανειοδραστικών ενώσεων, όπως το βρωμιούχο δεκαεξυλοτριμεθυλαμμώνιο (CTAB) ή το βρωμιούχο δεκαεξυλοτριμεθυλo φοσφώνιο (PC16) από αντίθετα φορτισμένους πολυηλεκτρολύτες. Mελετήθηκαν διαφορετικές πολυμερικές μήτρες που αποτελούνται είτε από εμπορικά διαθέσιμα πολυμερή είτε συντεθήκαν για αυτό το σκοπό, έτσι ώστε να γίνει κατανοητή η επίδραση της χημικής δομής του πολυμερούς στη ταχύτητα δέσμευσης και αποδέσμευσης των δραστικών συστατικών. Καθώς τα ιόντα αυτά έχουν βιοστατική δράση, απώτερος πρακτικός στόχος της διερεύνησης είναι η πιθανή εφαρμογή τέτοιων υβριδικών πολυμερικών υλικών σε υφαλοχώματα που θα εμποδίζουν την απόθεση θαλάσσιων βιοαποθέσεων και θα χαρακτηρίζονται από ιδιότητες «αυτοκαθαρισμού». Έτσι, παρασκευάστηκαν στατιστικά ή συσταδικά αμφίφιλα συμπολυμερή, στα οποία το υδρόφιλο μονομερές μπορεί να δεσμεύσει τα ιόντα Cu2+ ή/και τις αντίθετα φορτισμένες επιφανειοδραστικές ενώσεις, όπως το στυρενοσουλφονικό νάτριο (SSNa), το μηλεϊνικό (ΜΑc) και το ακρυλικό οξύ (ΑΑ), ενώ το υδρόφοβο μονομερές, το οποίο εισάγεται για τον έλεγχο του ισοζυγίου υδροφιλικότητας/υδροφοβικότητας, είναι ο μεθακρυλικός μεθυλεστέρας (ΜΜΑ). Έτσι, χρησιμοποιήθηκαν ομοπολυμερές PSSNa αλλά και συμπολυμερή του MAc με το SSNa (P(SSNa50-co-MANa). Επιπλέον, για συγκριτικούς λόγους παρασκευάστηκε και το συμπολυμερές του ΜΑc με οξικό βινυλεστέρα, (P(VAc-co-MAc), ενώ χρησιμοποιήθηκε και το εναλλασσόμενο συμπολυμερές του μηλεϊνικού οξέος με αιθυλένιο, P(Eth-alt-MAc). Τα στατιστικά αμφίφιλα συμπολυμερή P(MMAx-co-SSNa), P(MMAx-co-AA) παρασκευάστηκαν με συμπολυμερισμό ελευθέρων ριζών, ενώ τα συσταδικά αμφίφιλα συμπολυμερή PMMAx-b-PSSNa και PSSNa-b-PMMAx παρασκευάστηκαν με πολυμερισμό ελευθέρων ριζών μέσω μεταφοράς ατόμου (ΑΤRP), χρησιμοποιώντας ως μακροεκκινητή είτε PMMA είτε PSSNa, αντίστοιχα. Τα μοριακά βάρη των συμπολυμερών χαρακτηρίστηκαν με SEC, ενώ η χημική τους δομή ταυτοποιήθηκε με 1H-NMR και FT-IR. Η εκατοστιαία σύσταση των συμπολυμερών σε μονάδες ΜΜΑ, x, κυμαίνεται στην περιοχή 10-65 mol%, όπως προσδιορίστηκε με 1H-NMR και TGA. Από τη συγκριτική μελέτη της αυτοοργάνωσης σε υδατικό διάλυμα των συσταδικών και των στατιστικών αμφίφιλων συμπολυμερών, P(MMAx-co-SSNa) και PSSNa-b-PMMAx) με ιχνηθέτηση με φθορίζοντες ιχνηθέτες διαπιστώθηκε πως τα συσταδικά συμπολυμερή εμφανίζουν σημαντικότερη τάση αυτοοργάνωσης, καθώς έχουν σημαντικά μικρότερη κρίσιμη συγκέντρωση μικκυλοποίησης και χαρακτηρίζονται από υψηλότερα επίπεδα υδροφοβικότητας. Η δέσμευση των ιόντων Cu2+ από τα παραπάνω συμπολυμερή σε αραιά υδατικά διαλύματα πραγματοποιήθηκε μέσω ιονoανταλλαγής χρησιμοποιώντας τη μετά νατρίου άλατος μορφή των συμπολυμερών ή μέσω εξουδετέρωσης της όξινης μορφής των συμπολυμερών με Cu(OH)2 και διερευνήθηκε με φυσικοχημικές μεθόδους, όπως η θολομετρία, η ιξωδομετρία τριχοειδούς και η φασματοσκοπία υπεριώδους-ορατού. Διαπιστώθηκε πως σε αραιά διαλύματα η δέσμευση των ιόντων Cu2+ οδηγεί σε συρρίκνωση των πολυμερικών αλυσίδων (ιξωδομετρία τριχοειδούς). Μάλιστα, σε αντίθεση με τα συμπολυμερή που περιέχουν SSNa, στα πολυμερή που περιέχουν καρβοξυλικές ομάδες, η συρρίκνωση είναι ιδιαίτερα ισχυρή και οδηγεί σε διαχωρισμό φάσεων καθώς η αναλογία των ιόντων Cu2+ προς τις καρβοξυλικές ομάδες προσεγγίζει τη στοιχειομετρία (θολομετρία), ως αποτέλεσμα του σχηματισμού συμπλόκων ένταξης μεταξύ των ιόντων Cu2+ και των καρβοξυλικών ομάδων (φασματοσκοπία υπεριώδους-ορατού). Μάλιστα, στην περίπτωση του P(Eth-alt-MAc), η φασματοσκοπία υπεριώδους-ορατού έδωσε σαφείς ενδείξεις για το σχηματισμό διπύρηνων συμπλόκων χαλκού με τις ομάδες καρβοξυλίου, τα οποία έχουν τη δυνατότητα να δράσουν ως σταυροδεσμοί δικτυώνοντας τις πολυμερικές αλυσίδες. Ως αποτέλεσμα, σε ημιαραιά διαλύματα σχηματίζονται υδροπηκτώματα. Ιδιαίτερο ενδιαφέρον έχει το γεγονός πως οι ιξωδοελαστικές ιδιότητες των σχηματιζόμενων υδροπηκωτμάτων εξαρτώνται σημαντικά από το χρόνο ανάμιξης των συμπολυμερών με τα ιόντα Cu2+. Στην επόμενη φάση διερευνήθηκε ο σχηματισμός μικτών συσσωματωμάτων (συμπλόκων) μεταξύ των πολυηλεκτρολυτών που περιέχουν SSNa και της αντίθετα φορτισμένης επιφανειοδραστικής ένωσης, CTAΒ. Στην περίπτωση του ομοπολυμερούς PSSNa ή των συσταδικών αμφίφιλων συμπολυμερών PSSNa-b-PMMAx παρατηρείται διαχωρισμός φάσεων, καθώς η αναλογία των αλληλεπιδρώντων ειδών προσεγγίζει τη στοιχειομετρία φορτίων. Αντίθετα, όταν χρησιμοποιούνται τα στατιστικά αμφίφιλα συμπολυμερή P(MMAx-co-SSNa) με x=33-47mol%, σχηματίζονται ιξώδη διαλύματα ή ασθενή πηκτώματα. Η ρεολογική διερεύνηση του φαινόμενου κατέδειξε πως εξαρτάται από τη συγκέντρωση του πολυμερούς, τη γραμμομοριακή αναλογία CTAΒ/SSNa και την ιοντική ισχύ του υδατικού διαλύματος. Πριν τις τελικές δοκιμές σε πραγματικές συνθήκες παρασκευάστηκαν αιδιάλυτα στο νερό υβριδικά υλικά πολυμερούς-χαλκού, ενδεχομένως παρουσία CTAΒ ή PC16 χρησιμοποιώντας όλες τις προηγούμενες οικογένειες συμπολυμερών αλλά και εμπορικά διαθέσιμα πολυμερή αντίστοιχης δομής. Χρησιμοποιώντας κατάλληλο εκλεκτικό αντιδραστήριο (bathocuproine) μελετήθηκε φωτομετρικά η αποδέσμευση των ιόντων Cu2+ σε υδατικό διάλυμα NaCl 1 M. Έτσι, διευκρινίστηκε η επίδραση διαφόρων παραγόντων στο ρυθμό αποδέσμευσης των ιόντων Cu2+, όπως η ύπαρξη υδρόφοβων μονομερών, το είδος και το ποσοστό αυτών, η αρχιτεκτονική (στατιστική ή συσταδική) των συμπολυμερών, η εισαγωγή και το είδος της επιφανειοδραστικής ένωσης, ο τρόπος εισαγωγής και το είδος της αλληλεπίδρασης με τα ιόντα Cu2+. Στο τελευταίο στάδιο, διερευνήθηκε η συμβατότητά/αναμιξιμότητα των παρασκευασθέντων βιοστατικών υλικών με τυπικές πολυμερικές μήτρες που μπορούν να χρησιμοποιηθούν σε υφαλοχρώματα. Στις περιπτώσεις που διαπιστώθηκε ικανοποιητική συμβατότητα/αναμιξιμότητα (συστήματα PSSNa/CTAB, PSSNa/PC16, P(SSNa50-co-MANa)/CuPC16, P(VAc-co-MANa)/Cu) και ήταν εφικτό, παρασκευάστηκαν τα αντίστοιχα υφαλοχρώματα. Η συμπεριφορά αυτών των υφαλοχρωμάτων διερευνήθηκε εργαστηριακά με ηλεκτρονική μικροσκοπία σάρωσης (SEM), όσον αφορά τις μορφολογικές μεταβολές της επιφάνειας και τις μεταβολές του πάχους του χρώματος σε επιταχυνόμενες συνθήκες αποδέσμευσης βιοστατικού (υδατικό διάλυμα 5M NaCl). Επίσης, μελετάται και η συμπεριφορά τους σε πραγματικές συνθήκες με τη βοήθεια ειδικής διάταξης σε ελεγχόμενο θαλάσσιο χώρο. / At this thesis, the parameters that influence the interaction and the release of copper ions and/or of cationic surfactants as hexadecyltrimethyl ammonium bromide (CTAB) or hexadecyltrimethyl phosphonium bromide (PC16) from opposite charged polyelectrolytes, are studied. Different polymeric matrixes that are consisted either by commercially available polymers or by polymers that were synthesized for this purpose, were used in order, the influence of the polymer structure to the release rate of copper ions, to be identified. As these ions can behave as biocides, the practical purpose of this study is the possible application of these polymers to self-polishing antifouling paints. Random or block amphiphilic copolymers, whose hydrophilic monomer can interact with copper ions and/or the surfactants, such as styrene sulfonate (SSNa), maleic acid (MAc) and acrylic acid (AA), while the hydrophobic one, which is introduced for the hydrophilicity/hydrophobicity control, such as methyl methacrylate (MMA), were prepared. In addition, for comparison, the copolymer of maleic acid with vinyl acetate (VAc), (P(VAc-co-MAc)) was prepared. The alternative copolymer of maleic acid with ethylene was also used. The random copolymers P(MMAx-co-SSNa), P(MMAx-co-AA) were synthesized by free radical polymerization while the block copolymers PMMAx-b-PSSNa and PSSNa-b-PMMAx were synthesized through atom transfer polymerization (ATRP), using either PMMA or PSSNa as macroinitiator. The molecular weights of the copolymers were determined by SEC while their structure was identified by 1H-NMR and FT-IR. The copolymer composition in MMA untis is between 10-65 mol% as it was determined by 1H-NMR and TGA. The ability of self-assembling of random and block copolymers (P(MMAx-co-SSNa) και PSSNa-b-PMMAx) in aqueous solution was studied by pyrene fluorescence probing. The block copolymers was found to present self-assembling properties as they have lower critical micellization concentration. The binding of Cu2+ by the above mentioned polymers in dilute solutions was achieved through ion-exchange procedure using the sodium salt form of the copolymers or through neutralization of the acid form of the polymers using Cu(OH)2. Tholometry, viscometry and UV-Vis spectrometry were used to study this binding. The interaction of Cu2+ with the polymers leads to the shrinkage of the polymer chains. To the copolymers that contain carboxylic groups this shrinkage is more intense and leads to macroscopic phase separation, as the ratio of Cu2+ to the carboxylic groups is near the stoichiometry, as a consequence of complexes formation. The UV-Vis study of P(Eth-alt- MAc) denoted the formation of binuclear complexes between the Cu2+ and the carboxylic groups. These complexes can behave as crosslinks of the polymer chains. As a result, in semi-dilute solutions, gels are formed. Interestingly, the viscoelastic properties of these gels are dependent on the time elapsed from the mixture of the Cu2+ with the polymer. The interaction of polyelectrolytes that contain SSNa units, with opposite charged surfactant CTAΒ was studied. The interaction of homopolymer PSSNa or of the blocks copolymers PSSNa-b-PMMAx with CTAB leads to phase separation as the ratio of these compounds is near the stoichiometry. On the contrast, the interaction of CTAB with random copolymers P(MMAx-co- SSNa) where x=33-47mol%, leads to the formation of very viscous solutions or weak gels. By the study of the rheological properties of these systems, the influence of the polymer concentration, the molar ratio CTAΒ/SSNa and the ionic strength was found. All the above mentioned polymers where used for the preparation of hybrid materials that contain Cu2+. CTAΒ ή PC16 were also introduced to some of them in order to take a water insoluble material. The final purpose of this thesis was to control the release of Cu+2 ions from the prepared hybrid materials in aqueous NaCl 1M solution. The Cu+2 -release studies were performed photometrically using a selective dye (bathocuproine). As a result, the influence of many parameters such as the presence of hydrophobic monomers, their type and their content, the architecture of the copolymers (random or blocks), the introduction and the type of surfactants, the way of introduction of copper ions to the polymers and the type of their interaction was studied. The compatibility of all these materials with matrixes which are used in the antifouling paints was studied. In case that this compatibility was satisfying, antifouling paints using these polymeric materials (PSSNa/CTAB, PSSNa/PC16, P(SSNa50-co-MANa)/CuPC16, P(VAc-co-MANa)/Cu) were prepared. The morphology of the surface of these paints and the changes to their thickness was studied by SEM after staying in aqueous solution of NaCl 5M. Their behavior to real conditions (sea) is being studied.
114

Avaliacao do comportamento frente a corrosao pelo ataque de cloreto de argamassa armada apos varios tratamentos protetores

CRIVELARO, MARCOS 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:46:53Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:47Z (GMT). No. of bitstreams: 1 08513.pdf: 9974543 bytes, checksum: 92f7076f974608407acb3c472a6d993b (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
115

To Evaluate and Study the relationship between employees’ commitment and individual performance : A Quantitative Approach- Case Study of Kansai Paints

Adnan, Sonia, Nhaily, Abir, Wang, Hongyu January 2018 (has links)
Nowadays the companies want to make sure that they have strong resources that can face the rapid changes in the environment. One of the most important resources is human resources. The interest of the companies to have committed employees have been increased because there is a big difference between the performance of committed employees and the rest of the employees. Committed employees perform well in the organization and help the organization to grow and face the competitive environment. Based on this, this research aims to evaluate and study the relationship between organizational commitment and individual performance.To do this one of the Multinational corporation(MNC) is selected, this MNC is the Japanese company Kansai Paint who has one subsidiary in Pakistan. The theoretical model of this study was formulated based on one dependent variable which is the individual performance and three independent variables which are an affective commitment, continuance commitment and normative commitment.The data of the research was collected by questionnaires which sent to 100 employees on Kansai Paint in Pakistan, and SPSS testing was used to analyze the data. The finding of the study exposed that the affective commitment, continuance commitment and normative commitment have a positive impact on the individual performance. At the end of the research, the conclusion of the research was drawn and several of recommendations were developed.
116

Surveillance et contrôle du moustique tigre, Aedes albopictus (Skuse, 1894) à Nice, sud de la France / Surveillance and control of the Tiger mosquito, Aedes albopictus (Skuse, 1894) in Nice, south of France

Boubidi, Saïd Chaouki 15 December 2016 (has links)
Le moustique tigre Aedes albopictus, pur produit de la mondialisation, s’est installé en Europe dans les années 1970s, et en région PACA en 2004, grâce au transport intercontinental de ses œufs, capables de résister à la dessiccation et d’effectuer une diapause. Ce moustique est capable de transmettre 27 virus comme la dengue, zika et chikungunya. Le premier objectif du présent travail a été l’étude des aspects biologique d’Ae. albopictus dans son milieu naturel dans une région où il s’est implanté depuis plus de 10 ans, à Nice au sud-est de la France. Nous avons utilisé différentes méthodes de captures : les pièges pour adultes BGs ®, les pièges pondoirs avec une infusion de foin pour la récolte des œufs ainsi que la capture sur Homme, afin d’apprécier la densité de ce moustique, ses fluctuations spatiotemporelles et les taux de parturité des femelles. Les deux années de l’étude de la dynamique saisonnière ont montrés un début d’activité des moustiques au mois d’avril atteignant un pique d’activité en Juillet-Août et diminuant par la suite jusqu'à ce que l'activité a cessé au mois de novembre. Nous avons enregistré des taux de parturité élevées qui se sont stabilisés entre 0,52 et 0,71 entre le mois de juin et octobre respectivement. Ces taux de parturités indiquent un taux de survie élevé qui pourrait être encore supérieur à cause du comportement de skip oviposition des femelles Ae. albopictus. De plus nous avons mis en évidence un taux important de femelles gravides (jusqu’à 44 %) capturées sur Homme indiquant une prise de repas multiples durant un même cycle gonotrophique. L'objectif principal de ce travail a été d'évaluer l'efficacité des pulvérisations spatiales d’Ultra Bas Volume (UBV) d’insecticides, la principale méthode utilisée dans le cas de foyers urbains. La population locale d’Ae. albopictus a montré une forte sensibilité à la deltaméthrine (le seul insecticide homologué pour lutter contre les moustiques adultes en France) bien que les mâles ont été beaucoup plus sensible que les femelles. Une comparaison des résultats par application topique et par les tests en tube OMS a confirmé que cette différence a été due à la plus petite taille des mâles par rapport aux femelles. Durant six essais sur le terrain, on n’a obtenu aucun impact significatif des traitements UBV de deltaméthrine sur les femelles, bien qu'il y ait eu une réduction significative des mâles. En revanche, le traitement par thermonébulisation autour d’un petit groupe de maisons a permis une quasi-élimination (95%) des moustiques mâles et femelles. Ces résultats apportent un élément de réponse sur les stratégies à mener en santé publique. Enfin, l'efficacité de plusieurs formulations de peintures insecticides issues de la technologie de microencapsulation ont été testée dans des conditions de laboratoire et de terrain. Les résultats ont été encourageants et les tests ont démontré que les peintures à base d’organophosphorés ont une rémanence de 2 ans. Le but ultime était d'utiliser des pièges pondoirs traités avec ces peintures insecticides comme une méthode de contrôle: en théorie, cette méthode vise l’exploitation du comportement de skip oviposition qui oblige les femelles à déposer leurs œufs sur plusieurs gîtes différents augmentant la probabilité pour que celles-ci rencontrent un piège pondoir traité avec un insecticide. Dans un petit essai sur le terrain, cependant, aucun impact sur la population sauvage n’a été observé. Nous discutons de cette méthode ainsi que de son intérêt face à la menace toujours grandissante liée à la propagation continuelle d’Ae. albopictus à travers le monde. / The Asian Tiger mosquito, Aedes albopictus, first appeared in Europe in the 1970s,almost certainly a result ofintercontinental transport of its dessication-resistant eggs. In the laboratory,the species is capable of transmitting 27 viruses including Yellow Fever, dengue, chikungunya and zika, although in the field it is not considered an efficient vector because it is not host-specific.The first objective of our studies was to monitor aspects of the biology of the species in Nice (southeastern France), where it has been established for more than 10 years. Infusion-baited ovitraps, B-G® adult traps and human landing captures were used to reveal seasonal population fluctuations, parous rates and other parameters. In two complete years of study, adult mosquitoes began to appear in April, reached a plateau in July-August and declined thereafter until activity ceased in November. Parous rates were stable from June to October (0,52 to 0,71%) indicating a balance between recruitment (eclosion) and mortality. During this period, daily survival probability was high although this may be an underestimate if the duration of the gonotrophic cycle is extended by skip oviposition. Up to 44% of females captured by landing capture were gravid, confirmation of multiple blood-meals per gonotrophic cycle.The main focus of the work was an assessment of the efficacy of Ultra-low Volume (ULV) space sprays, the principal method used in the event of urban outbreaks. The local population proved highly susceptible to deltamethrin (the only insecticide approved for adult mosquito control in France) although femaleswere significantly less susceptible than males. A comparison of results by topical application and by the WHO tube test confirmed this difference is a function of size. In six separate field trials,there was no evidence of any impact of ULVdeltamethrin on females although there was a significant reduction of males. By contrast, outdoor treatment of a small cluster of homes with a portable thermal fogger gave virtual elimination (ca. 95%) of both sexes.These results are clearly of public health significance.Lastly, the efficacy of several slow-release formulations of microencapsulated insecticide in paint was tested in laboratory and semi-field conditions. Results were encouraging and tests demonstrated that the paints remained effective for 24 months on plastic surface. The ultimate goal was to use paint-treated ovitraps as a control method: in theory, skip ovipositon should ensure a high probability that ovipositing females will make contact with a treated trap on their rounds of suitable oviposition sites. In a small field trial, however, no impact on the wild population was observed. This may have been because too few treated traps were deployed; further studies along these lines could prove worthwhile.
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Avaliacao do comportamento frente a corrosao pelo ataque de cloreto de argamassa armada apos varios tratamentos protetores

CRIVELARO, MARCOS 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:46:53Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:47Z (GMT). No. of bitstreams: 1 08513.pdf: 9974543 bytes, checksum: 92f7076f974608407acb3c472a6d993b (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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Avaliação físico-química, ecotoxicológica e biorremediação microbiológica de bases e pigmentos de tintas acrílicas / Physico-chemical, ecotoxicological, and microbiological bioremediation of water based paints foundations and pigments

Vieira, Thaís Maitan 14 October 2016 (has links)
Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2016-12-19T11:04:10Z No. of bitstreams: 2 Dissertação - Thaís Maitan Vieira - 2016.pdf: 2831795 bytes, checksum: 3b1f65572e41da1041961061a32845bd (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-12-26T14:40:29Z (GMT) No. of bitstreams: 2 Dissertação - Thaís Maitan Vieira - 2016.pdf: 2831795 bytes, checksum: 3b1f65572e41da1041961061a32845bd (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-12-26T14:40:29Z (GMT). No. of bitstreams: 2 Dissertação - Thaís Maitan Vieira - 2016.pdf: 2831795 bytes, checksum: 3b1f65572e41da1041961061a32845bd (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-10-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The growth of civil construction and industrial activities is increasing environmental concern due to the consequent release of organic and inorganic compounds in nature, arising from these activities. The use of vehicles, pigments, additives and solvents, corresponds to an example of activity that causes environmental impacts poorly studied. It is known that the construction workers use water to clean work equipment and most of the time, the disposal of this water does not suffer any previous treatment. Moreover, the very paint industries also generate waste in need of treatment. In this sense, the objective of this study is to analyze the chemical compositions, the harmful effects to aquatic environments and develop bioremediation processes for different commercial acrylic paints and propose to society the use of foundations and pigments less impact to the environment. With regard to potentially toxic chemicals, C and BFA foundations are those with lower levels of these chemicals. Among the pigments, the Yellow ZC, Blue and Green are those who had the lowest levels of potentially impactful chemicals from an environmental point of view. Considering the VOC present in the bases and pigments, the foundations A and B, and the pigments violet, Yellow NT and Yellow US are the most suitable, because they showed the presence of VOC less dangerous. The ecotoxicological point of view, the foundations A, B and C and the pigments violet, Red, Black, Yellow US and Yellow NT are the most suitable because of lower toxicity. Thus, considering the environmental and occupational exposure approach, the BFA foundation is not advisable to use the foundations A and B must be used indoors and the foundation C outdoors. For pigments advises to use the colors Violet, Yellow NT and Yellow US for indoor, and Yellow ZC and Blue to external environments without the other pigments are vetted to be added in small amounts the bases. Regarding the bioremediation of aquatic environments freshwater by the presence of foundations and pigments, Bacillus cereus (CEM 2) showed greater efficiency in bioflocculation of the compounds in 24 hours, demonstrating potential for biotechnological use in the bioremediation for acrylic paints waste. / O crescimento da construção civil e industrial vem aumentando a preocupação ambiental devido a consequente liberação de compostos orgânicos e inorgânicos na natureza, oriundos dessas atividades. O uso de tintas compostas por veículos, pigmentos, aditivos e solventes, corresponde a um exemplo de atividade que causa impactos ambientais ainda pouco estudados. Sabe-se que os trabalhadores da construção civil utilizam da água para limpeza de seus equipamentos de trabalho e, na maioria das vezes, o descarte dessa água não sofre nenhum tratamento prévio. Além disso, as próprias indústrias de tintas também geram efluentes que precisam de tratamento. Nesse sentido, o objetivo desse trabalho foi analisar as composições químicas, os efeitos deletérios para ambientes aquáticos e desenvolver processos de biorremediação para diferentes tintas acrílicas comerciais, propondo à sociedade a utilização de bases e pigmentos menos impactantes ao meio ambiente. Com relação aos elementos químicos potencialmente tóxicos, as bases C e BFA são as que apresentam menores teores desses elementos químicos. Dentre os pigmentos, o Amarelo ZC, o Azul e o Verde são os que apresentaram os menores teores dos elementos químicos potencialmente impactantes do ponto de vista ambiental. Considerando os VOC presentes nas bases e pigmentos, as bases A e B e os pigmentos Violeta, Amarelo NT e Amarelo US são os mais indicados, pois apresentaram a presença de VOC com menor periculosidade. Do ponto de vista ecotoxicológico, as bases A, B e C e os pigmentos Violeta, Vermelho, Preto, Amarelo US e Amarelo NT são os mais indicados devido a menor toxicidade. Com isso, considerando o enfoque ambiental e de exposição ocupacional, a base BFA não tem o uso aconselhável, as bases A e B devem ser usadas em ambientes internos e a base C em ambientes externos. Para os pigmentos aconselha-se o uso das cores Violeta, Amarelo NT e Amarelo US para ambientes internos e Amarelo ZC e Azul para ambientes externos, sem que os demais pigmentos sejam vetados por serem adicionados em pequenas quantidades as bases. Com relação a biorremediação de ambientes aquáticos dulcícolas pela presença de bases e pigmentos, o Bacillus cereus (CEM 2) apresentou maior eficiência na biofloculação dos compostos em 24 horas, demonstrando potencial biotecnológico de sua utilização como biorremediador para efluentes de tintas acrílicas.
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La couleur dans la civilisation Nasca : production tinctoriale et picturale / Colour in the Nasca civilization : the production of dyes and paints

Boucherie, Nathalie 14 June 2014 (has links)
Cette thèse se propose d’étudier de manière approfondie les matières colorantes et les techniques de coloration appliquées aux textiles de la culture Nasca. Cette civilisation préhispanique, sans écriture, s’est développée sur la côte sud du Pérou pendant environ neuf siècles (200 ans av. J.-C. ; 700 ans apr. J.-C.). Parmi sa culture matérielle, les textiles sont abondants et nombre d’entre eux sont de grande finesse avec des décors polychromes. La polychromie avait probablement une signification dans la cosmogonie Nasca et le textile est particulièrement chargé de sens dans la culture andine. Pourtant, les matériaux de la couleur demeurent un sujet encore méconnu dans le domaine textile. Il semblait donc intéressant d’identifier au moyen de méthodes physico-chimiques les matières colorantes utilisées par les artistes textiles Nasca. Pour ce faire, une enquête de terrain a été menée en amont pour récolter et identifier les sources colorantes susceptibles d’avoir été employées. Puis un corpus textile a été constitué avec des textiles inédits, issus de fouilles récentes menées sur les sites de Los Molinos, Estaqueria et Cahuachi, l’ancien centre politico-cérémoniel des Nasca. Quelques tissus d’autres cultures (Topará, Mochica et Nasca drivé) ont aussi été analysés pour établir des comparaisons.Les résultats fournissent de précieuses informations qui caractérisent la production tinctoriale et picturale des textiles Nasca. Au-delà de cet aspect technique, ces données sont utiles pour aborder sous un autre angle des problématiques archéologiques plus complexes notamment lorsque l’attribution culturelle des textiles est inconnue ou discutée, comme ceux de la péninsule de Paracas. / This thesis’ aim is to propose an in-depth study of the dye-sources and dyeing and colouring techniques used for textiles in the Nasca civilization. This Pre-Columbian, pre-literate civilization flourished on the southern coast of Peru during some nine centuries (200 BC to 700 AD). In its material culture, textiles are very numerous and many of them are of outstanding quality, with a rich polychromatic ornamentation. Polychromy probably was of great significance among the Nasca and textiles seem to always have been of particular importance in Andean culture. Nevertheless, the material sources of the colours on these dyed and painted textiles have remained a comparatively poorly explored research field. It therefore appeared as a promising, innovative quest to try and identify the colouring matters used by Nasca textile artists, using state-of-the art physico-chemical analytical methods. To this effect, botanical and anthropological field missions were first conducted in order to identify and collect colouring sources that might have been employed by the Nasca dyers and textile painters. A corpus of archaeological textiles was assembled, selecting textiles discovered in the course of recent archaeological excavations on the sites of Los Molinos, Estaqueria and Cahuachi, the latter being the antique political and ceremonial centre of the Nasca civilization. A number of textiles from other cultures (Topará, Mochica and Nasca-derived) were also analyzed to allow comparisons.Our results bring precious new information on the production of dyes and paints on Nasca textiles. Allowing even further prospects than these important technical discoveries, they bring new light into complex archaeological issues, such as the cultural attribution of archaeological textiles whose provenance is unknown or disputed, which is the case for some textiles from the Paracas peninsula.
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ESTUDO DA RELAÇÃO ENTRE OS NÍVEIS DE INDICADORES BIOLÓGICOS DE EXPOSIÇÃO AO TOLUENO E O ESTRESSE OXIDATIVO EM EXPOSTOS OCUPACIONALMENTE A TINTAS / STUDY OF THE RELATIONSHIP BETWEEN THE LEVELS OF BIOLOGICAL EXPOSURE INDICES AND OXIDATIVE STRESS IN OCCUPATIONALLY EXPOSED TO PAINTS

Moro, Angela Maria 19 March 2010 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Paints occupational exposure is an important health problem due to the wide variety of chemicals and xenobiotics present in their constitution. Organic solvents and heavy metals are among the main chemical constituents of paints. In the view of the variety of substances found in paints, can be noted that painters are simultaneously exposed to various xenobiotics, suggesting a case of co-exposure or exposure mixed. Biological monitoring is an essential tool for assessing the risk to health and occupational health practices. Moreover, it is known that there is a close relationship between the xenobiotics constituents of paints and oxidative stress, such as toxicological mechanism. In this study was evaluated oxidative damage by quantification of blood biomarkers of oxidative stress such as malondialdehyde (MDA), reduced glutathione (GSH), δ-aminolevulinate dehydratase enzyme (ALA-D), superoxide dismutase (SOD) and catalase (CAT ), in individuals occupationally exposed to paints (n = 48) and non-exposed subjects (n = 30). Biological monitoring of toluene was performed by quantification of different biomarkers of exposure, urinary hippuric acid and ortho-cresol, and blood toluene. For xylene, styrene, ethylbenzene and lead were quantified urinary levels of methylhippuric acid, mandelic acid, phenylglyoxylic acid and blood lead, respectively. Despite all IBEs were below the biological limit exposure (BEL), significant changes in oxidative stress biomarkers were found in exposed group. Plasma levels of MDA and blood antioxidant enzymes (SOD and CAT) had shown increased in the group of painters when compared with non-exposed group; this increase was accompanied by GSH levels depletion and enzyme ALA-D inhibition. It was also observed several correlations between the oxidative stress biomarkers and biomarkers of exposure to xenobiotics present in paints. By statistical tests were evaluated which of the paints constituents played the greatest influence on changes in oxidative stress biomarkers, in this case of co-exposure. Among the exposure biomarkers tested, blood toluene was suggested as the main responsible for increased lipid peroxidation; in addition, it was appointed as a new and important inhibitor of the enzyme ALA-D. Thus, it is suggested that a joint evaluation of biomarkers of exposure and oxidative stress biomarkers might be useful to ensure, in longterm, the worker s health. / A exposição ocupacional a tintas representa um importante problema de saúde devido à ampla variedade de substâncias químicas e xenobióticos presentes na sua constituição. Solventes orgânicos e metais pesados encontram-se entre os principais compostos químicos constituintes das tintas. Tendo em vista a variedade de substâncias presentes na composição das tintas, pode-se constatar que pintores encontram-se simultaneamente expostos a diferentes xenobióticos, caracterizando um processo de coexposição ou exposição mista. A monitorização biológica é uma ferramenta essencial para a avaliação do risco à saúde e práticas de saúde ocupacional. Por outro lado, sabe-se que existe uma estreita relação entre os xenobióticos constituintes de tintas e o estresse oxidativo, como mecanismo toxicológico. Neste estudo foi avaliado o dano oxidativo, através da quantificação de biomarcadores sanguíneos do estresse oxidativo, como alondialdeído (MDA), glutationa reduzida (GSH), enzima δ-aminolevulinato desidratase (ALA-D), superóxido dismutase (SOD) e catalase (CAT); em indivíduos expostos (n=48) e não expostos (n=30) ocupacionalmente a tintas. A monitorização biológica do tolueno foi realizada através da quantificação dos diferentes biomarcadores de exposição, ácido hipúrico e orto-cresol urinários, e tolueno sanguíneo. Para xileno, estireno, etilbenzeno e chumbo foram quantificados os níveis urinários dos ácidos metil-hipúrico, mandélico, fenilglioxílico, e chumbo sanguíneo, respectivamente. Apesar de todos os IBEs se encontrarem abaixo dos índices biológicos máximos permitidos (IBMP), alterações significativas nos biomarcadores do estresse oxidativo foram encontradas no grupo de expostos. Os níveis plasmáticos de MDA e das enzimas sangüíneas antioxidantes (SOD e CAT) se mostraram aumentados no grupo de pintores quando comparados com o grupo não exposto; esse aumento foi acompanhado pela depleção nos níveis de GSH e inibição da enzima ALA-D. Foram observadas ainda várias correlações entre os biomarcadores do estresse oxidativo e biomarcadores de exposição aos xenobióticos presentes nas tintas. Através de testes estatísticos foram avaliados quais dos constituintes das tintas desempenhavam maior influência sobre as alterações nos biomarcadores de estresse oxidativo, nesse caso de co-exposição. Dentre os biomarcadores de exposição analisados, o tolueno sanguíneo foi sugerido como o principal responsável pelo aumento da peroxidação lipídica; além de ser apontado como um novo e importante inibidor da enzima ALA-D. Dessa forma, sugere-se que a avaliação conjunta de biomarcadores de exposição e biomarcadores do estresse oxidativo possa ser útil para assegurar, em longo, prazo a saúde do trabalhador.

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