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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.
61

Onomastique de l’art culinaire en France / Onomatics of the Culinary Art in France

Faivre, Carole 14 September 2012 (has links)
La gastronomie et l'onomastique n'ont encore jamais fait l'objet d'étude, de manière conjointe, d'un point de vue linguistique. L’objectif de cette thèse est de proposer un point de départ à une réflexion sur la structure, la nature et la place du nom propre dans la gastronomie française. Pour ce faire, après avoir exposé les différentes problématiques liées à la définition des concepts de gastronomie et de nom propre, nous avons réalisé une synthèse des principaux éléments théoriques qui servent de base à la recherche sur les noms de plats, tant sous un angle linguistique, historique qu’artistique ou législatif. La nécessité d’effectuer une distinction entre appellation culinaire et dénomination gastronomique selon la place qu’occupe le nom de plat sur un axe nom propre / nom commun s’est vite imposée et pour vérifier dans quelle mesure les types de noms propres dans les noms de plats sont conditionnés par le contexte, deux sortes de corpus ont été constitués. Sera d’abord traitée l’évolution du nom propre dans la gastronomie à travers le prisme de la norme dictionnairique au cours des 70 dernières années, au moyen d'une comparaison lexicographique des deux éditions du Larousse Gastronomique (1938 et 2007). Pour ce faire, une catégorisation des noms propres relevés dans le corpus a été établie. Dans un deuxième temps, la place des noms propres dans un corpus témoignant de l’usage a été examinée, en rassemblant des menus de restaurants parisiens ainsi que des dépliants publicitaires de la restauration livrée. / Gastronomy and onomastics have never previously been the subject of a joint study from a linguistic point of view. The objective of this thesis is to provide a starting point for research on the structure, nature and place of proper names in French gastronomy. After considering the various problems related to the definition of such concepts as gastronomy and proper name, we achieved a synthesis of the main theoretical elements that form the basis for research on the names of dishes from a linguistic, artistic, historic or legislative perspective. Then, a distinction was made between culinary denomination and gastronomic designation in relation to the place of a dish name on a proper name / common name axis, although the separation between the two poles is sometimes blurred and cannot be considered to be strict. Two kinds of corpus are established in order to verify that the types of proper names in gastronomy depend on the context where dish names originate. First, the evolution of the proper name in gastronomy over the past 70 years is studied from a normative perspective through the lexical comparison of the first and the latest editions of the Larousse Gastronomique (1938 and 2007) and the establishment of a categorization of proper names. Second, proper names in a corpus reflecting the use was examined using Parisian restaurant menus and flyers advertising for food delivery. The comparison of the results for the two types of corpus will shed light on the differences, both quantitative and classificatory, in the use of proper names in a normative or in a creative context.
62

Le nom fois et les expressions dérivées : étude sémantique et pragmatique dans la phrase et dans le discours / The Name Fois and Derived Expressions Semantic and Pragmatic Study in Sentence and Discurse

Guiraud, Anne-Marie 12 June 2012 (has links)
L'objectif de cette recherche est de définir les significations du N (nom) fois au travers des principales constructions qui l'utilisent en français contemporain, et d‟expliquer la formation des expressions dérivées autrefois, des fois (que), parfois, quelquefois, toutefois, une fois (que). Examiné sous l'angle du lexique, le mot fois est un substantif féminin, qui, précédé d'un déterminant, se constitue en groupe nominal (GN). Le N fois dénote un comptage d'occurrences, c'est-à-dire d'unités de discours, qui sont le plus souvent des processus verbaux ou des prédicats. Il s'agit donc d‟unités linguistiques ce qui explique que fois apparaît dans des contextes divers. Nous avons classé les principales constructions en fonction des déterminants relevés dans le GN fois. D'une part, les GN composés des adjectifs cardinaux ou quantificateurs + fois permettent de compter des occurrences du langage et ont une fonction adverbiale de quantification ; si les occurrences comptées sont des processus verbaux, ils portent en sus une notion temporelle à valeur itérative ou fréquentielle. Avec les autres déterminants (article défini et indéfini, adjectif démonstratif, quantificateurs universels tous les et chaque), fois est un nom temporel qui tend à se standardiser. Les expressions dérivées évoluent sémantiquement et produisent une forme adverbiale préalable à d'autres transformations. Nous pouvons ainsi identifier le groupe des adverbiaux de quantification, le plus ancien, qui a facilité l'apparition des expressions dérivées, et un groupe plus récent où fois apparaît comme un nom temporel au même titre que jour, instant ou moment. / We aim in this search to define the significations of N (name) fois through the main constructions using it in modern French, and to explain how it helped in forming the derived expressions autrefois, des fois (que), parfois, quelquefois, toutefois, une fois (que). From a lexical point of view, the word fois is a feminine substantive, and, built with a determiner, it forms a nominal group (NG). The N fois denotes an occurrences counting, that means discurse units counting, mostly verbal process or predicates. Therefore it concerns liunguistic units and that's why fois is used in several contexts. We organized the main constructions according to the determiner used in NG fois. Firstly, NG built with cardinal adjectives or quantifiers + fois allow counting language occurrences and function as a quantification adverb ; if the occurrences are verbal process, they bring besides a temporal notion with iterative or frequential value. With other déterminers (definite and indefinite article, demonstrative adjective, universal quantifiers tous les and chaque), fois is a temporal name on the way to standardisation. The derived expressions change semantically and come to an adverbial form prior other transformations. This concludes to identify the group of quantification adverbs, the former one, which helped the formation of derived expressions, and a newer group in which fois is a temporal name as jour, instant or moment.
63

Etude comparative des verbes supports faire, donner et prendre - buat/membuat, beri/memberi et ambi/memgambil en français en français et en malais / A comparative study of the support verbs to do, to give, to take – buat/membuat, beri/memberi and ambil/mengambil in French and Malay languages

Bin Hassan Hussin, Omrah 03 June 2009 (has links)
Cette thèse propose une étude comparative de trois verbes supports, faire/membuat, donner/memberi et prendre/mengambil en français et en malais. La méthode utilisée est celle du Lexique-Grammaire de Maurice Gross et celle de la théorie de l’Analyse Matricielle Définitoire d’Amr Helmy Ibrahim. Notre objectif est de décrire les propriétés formelles des phrases à verbes supports en français et en malais et de les comparer du point de vue syntaxique et sémantique. Nous avons appliqué quatre tests de reconnaissance du verbe support afin de déterminer le statut de ces trois verbes dans les constructions étudiées. Notre étude est structurée en six chapitres. Dans le premier chapitre, nous exposerons des notions importantes : la définition du support et les différents points de vue de certains linguistes qui se sont intéressés à l’étude du verbe support dans le cadre théorique du Lexique-Grammaire. Le deuxième chapitre donne une présentation générale du malais. Le troisième chapitre présente le verbe support buat/membuat (faire) en malais. Le quatrième chapitre présente l’étude du verbe support beri/memberi (donner) en malais. Le cinquième chapitre présente l’étude du verbe support ambil/mengambil (prendre) en malais. Le sixième chapitre présente l’étude comparative des verbes supports faire (membuat), donner (memberi) et prendre (mengambil) en français et en malais. Les résultas obtenus nous ont montré que le français et le malais partagent les mêmes caractéristiques générales des verbes supports. Ces résultats nous ont permis également de montrer que malgré l’universalité du phénomène, chaque langue possède ses propres mécanismes concernant le fonctionnement des verbes supports et le système de la détermination. / This thesis proposes a comparative study of three support verbs, also called sometimes in English « light verbs », faire/membuat “to do”, donner/memberi “to give” and prendre/mengambil “to take” in French and Malay languages. The method used is that of the Lexicon-Grammar of Maurice Gross and that of theory of the Defining Matrix Analysis of Amr Ibrahim. Our objective is to describe the formal properties of the sentences containing support verbs in French and Malay and to compare them from the syntactic and semantic point of view. We have bracket four tests of recognition of the support verb in order to determine the statue of these three verbs in the studied construction. Our study is structured in six chapters. In the first chapter, we expose the main notion: the definition of the support and the different points of view of the linguists that took an interest in the study of the support verb in the framework of the Lexicon-Grammar. The second chapter is a general presentation of the Malay language. The third chapter is the study of the verb support “membuat/faire” (to do) in Malay. The forth chapter is a study of the support verb “memberi/donner” (to give) in Malay. The fifth chapter is a study of the support verb “mengambil/prendre” (to take) in Malay. The sixth chapter is a comparative study between the three support verbs membuat/faire (to do), memberi/donner (to give) and mengambil/prendre (to take) in Malay and French. The results obtained have shown that the support verbs in French and Malay share the same general characteristics. These results also enabled us to show that in spite of the universality of the phenomenon, each language has its own mechanism concerning the function of the support verb and the system of determination.
64

Etude comparée du droit d'auteur et des droits de la personnalité / Comparative study of author's rights and personality's rights

Pascal, Marie-Alice 17 December 2011 (has links)
La confrontation entre droit d'auteur et droits de la personnalité vise à enrichir la théorisation des droits de la personnalité, qui souffrent d'une absence de catégorisation d'ensemble et d'une inadaptation du fondement juridique qui leur est assigné. La démarche peut surprendre car, tandis que le droit d'auteur a vocation à protéger une œuvre de l'esprit et permettre son exploitation, les droits de la personnalité sont attachés à la protection de l'individu. Pourtant, en dépit de cette différence manifeste d'objet, mais également de fondement juridique, ces deux catégories de droits se rejoignent autour de la notion de personnalité. Cette notion est, en effet, centrale en droit d'auteur français car, une œuvre de l'esprit se présente comme une manifestation de la personnalité de son créateur, expliquant, de ce fait, que le droit d'auteur soit qualifié de "personnaliste". De la même manière, les droits de la personnalité sont tournés vers les manifestations de la personnalité d'un individu à travers les éléments qui le caractérisent. Et si, traditionnellement, ces droits sont consacrés à la défense de l'intégrité morale des personnes physiques, on constate qu'ils font aujourd'hui l'objet de conventions. L'influence de la prise en compte de la personnalité se retrouve ainsi, d'une manière commune, à travers les contrats d'exploitation d'une œuvre de l'esprit, comme de ceux organisant la commercialisation de l'image, du nom ou de la voix d'un individu et explique que leur régime soit souvent analogue. Le constat de l'analogie du régime d'exploitation du droit d'auteur et des droits de la personnalité invite à s'interroger sur le voisinage de leurs natures juridiques respectives et soulève la question de la nature dualiste des droits de la personnalité. / The purpose of a comparative study of author's rights and personality's rights is to improve the theorisation of personality's rights. These rights suffer from a lack of wider categorisation together with inadaptation of their legal basis. The approach taken in this study may be surprising. Indeed, the intent of author's rights is to protect works of the mind and give authors exclusive rights to use them, when personality's rights intend to protect the rights of an individual. Nonetheless, and despite the difference between their legal basis, these two categories of rights converge around the notion of personality. This notion of personality is undeniably essential in French author's law, which is based on the view that a creative work is an expression of the author's personality. Similarly, personality's rights are considered to protect the expression an individual's personality. If traditionally, the purpose of these rights is to defend the moral integrity of individuals, we noticed today that these rights are subject to contracts. The fact that the concept of personality is respectively found in agreements regarding the exploitation of works of the mind as in those regulating the commercial use of one's name, image, likeness or voice, explains that these legal concepts are often comparable. The analogy between the author's right and the personality's rights exploitation procedures raises the questions of the parallel between their respective legal nature and of the dual nature of personality rights.
65

Adsorpciono ponašanje odabranih organskih ksenobiotika na sorbentima relevantnim za tretman voda / Adsorption behaviour od selected organic xenobiotics relevant for water treatment

Leovac-Maćerak Anita 10 March 2017 (has links)
<p>Fokus ove doktorske disertacije je bilo izučavanje sorpcionog pona&scaron;anja tri herbicida koji se nalaze na listi prioritetnih supstanci prema Okvirnoj Direktivi o vodama EU (2000/60/EC) sa generalnim ciljem dobijanja podataka korisnih za prioritizaciju na osnovu novog fundamentalnog znanja o efikasnosti (ad)sorpcije za uklanjanje ovih<br />supstanci iz&nbsp; vode u lokalno specifičnim uslovima. Odabrani su ksenobiotici različite rastvorljivosti, hidrofobnosti i donorsko-akceptorskih osobina, koji&nbsp; pripadaju&nbsp; različitim klasama&nbsp; herbicida (dinitroanilinski-trifluralin, hloroacetamidni-alahlor i triazinski-&nbsp; atrazin). Prva faza je obuhvatala karakterizaciju sorbenata i vodenih matriksa .U sintetičkom matriksu, trifluralin pokazuje veći afinitet na ispitivanim sedimentima u odnosu na alahlor i atrazin. I u slučaju organoglina, sorpcija je najizraženija za trifluralin. Alahlor i atrazin pokazuju slične sorpcione kapacitete na TMA-K, dok je na TMA-B, sorpcija izraženija za alahlor u odnosu na atrazin. U&nbsp; zavisnosti od prirodnog matriksa, na oba sedimenta, najveće&nbsp; Kd vrednosti su dobijene za trifluralin, dok su Kd vrednosti za atrazin i alahlor&nbsp; bile veoma slične ili&nbsp;pak veće za atrazin. U slučaju organoglina, vrednosti&nbsp; K<sub>d</sub> su rasle sa porastom log&nbsp; K<sub>OW</sub> vrednosti herbicida na TMA-K u oba prirodna matriksa. Kada je u pitanju TMA-B, rast K<sub>d </sub>vrednosti sa rastom log&nbsp; K<sub>OW</sub> vrednosti uočava se u povr&scaron;inskom matriksu pri C<sub>e</sub>&nbsp; = 0,05 mg/l i 0,5 mg/l, i podzemnom matriksu pri najvećoj ravnotežnoj koncentraciji C<sub>e</sub>&nbsp; = 0,5 mg/l. Kao najefikasniji sorbenti su se pokazali&nbsp; TMA-B&nbsp;(Kd&nbsp; = 10,5 -&nbsp; 483 l/kg) i model sediment (Kd = 16,4 -&nbsp; 761 l/kg). Odsustvo jasne linearne korelacije izmeĎu&nbsp; Kd i&nbsp; % TOC upućuje na važnost interakcija mineralne faze i herbicida. U slučaju sedimenata nisu utvrđene korelacije K<sub>d</sub> sa log&nbsp; K<sub>OW&nbsp;</sub>vrednostima, dok kod organoglina one postoje. K<span id="cke_bm_184S" style="display: none;">&nbsp;</span><sub>d</sub><span id="cke_bm_184E" style="display: none;">&nbsp;</span> /K<sub>OW</sub> odnosi su najveći kod atrazina na svim sorbenti<span id="cke_bm_185E" style="display: none;">&nbsp;</span>ma pa se pretpostavlja da on najvi&scaron;e učestvuje u&nbsp; uspostavljanju specifičnih interakcija zbog svojih donorsko-akceptorskih osobina. &Scaron;to se tiče uticaja DOC,&nbsp; zaključuje se da poreĎenje efikasnosti sorbenata treba sprovoditi u prirodnim matriksima jer sorpcioni koeficijenti variraju u zavisnosti od&nbsp;koncentracije polutanata, tipa i sadržaja DOC. Kolonskim eksperimentima je pokazano da atrazin i alahlor prolaze kroz kolonu sedimenta, dok je trifluralin skoro u potpunosti adsorbovan i u vrlo maloj koncentraciji detektovan u efluentu &scaron;to je u saglasnosti sa rezultatima &scaron;aržnih eksperimenata na ovom sorbentu. Procenjeni faktor retardacije pomoću modela TransMod za atrazin je veći u prirodnim matriksima (R <span id="cke_bm_190S" style="display: none;">&nbsp;</span><sub>d</sub><span id="cke_bm_190E" style="display: none;">&nbsp;</span> = 54 i R<sub>d</sub> = 55 u podzemnoj i povr&scaron;inskoj vodi, redom) nego u sintetičkoj&nbsp;vodi (R<sub> d</sub> = 40). Kod alahlora nisu uočene značajne promene faktora retardacije meĎu matriksima (R<sub> d</sub> = 30-35). Ovi rezultati su suprotni očekivanjima na osnovu hidrofilnosti ksenobiotika i mogu biti&nbsp; rezultat upravo interakcija sa organskim materijama koje su bile izražene u kolonskim testovima, verovatno i vi&scaron;e nego u &scaron;aržnim testovima gde se nije pojavilo povećanje R<sub>d</sub> vrednosti u prirodnim matriksima u odnosu na sintetički matriks.&nbsp; Bez obzira &scaron;to je&nbsp; alahlor hidrofobniji od atrazina, u uslovima datog matriksa i sorbenta ispoljava slične (&scaron;aržni testovi) ili<br />slabije sorpcione karakteristike&nbsp; (kolonski testovi)&nbsp; koje upućuju na mobilnost kroz prvi za&scaron;titini sloj.&nbsp; Treća faza je obuhvatala ispitivanje adsorpcije herbicida na aktivnim ugljevima u prahu. Ispitana je kinetika adsorpcionog procesa određivanjem koeficijenta za unutarčestični prenos mase herbicida u sirovim i ozoniranim prirodnim matriksima. Određena je efikasnost uklanjanja herbicida na razlilčitim ugljevima u prahu. Efikasnost uklanjanja se kretala u različitim opsezima u zavisnosti od odabranog uglja, vodenog matriksa i doze uglja. Na komercijalnim ugljevima najveća postignuta efikasnost (doza uglja od 15 mg/l) za&nbsp; alahlor iznosi u povr&scaron;inskoj vodi 95%, a u podzemnoj 76%. Za atrazin to je u povr&scaron;inskoj vodi 58% i u podzemoj vodi 56%, a za trifluralin u povr&scaron;inskoj vodi 87%, a u podzemnom matriksu 92%. Na uglju sitnih čestica koji se koristi u kombinaciji sa membranskom filtracijom ove<br />vrednosti su&nbsp; i veće. Stepen uklanjanja DOC na komercijalnim ugljevima (pri dozi od 15 mg/l) iznosi do 57% za povr&scaron;inski matriks i do&nbsp; 51% za podzemni matriks. Slična efikasnost u uklanjanju DOC je postignuta i na uglju sitnih čestica u oba matriksa. Ozonizacija je ispoljila očekivan negativan uticaj, vi&scaron;e ili manje izražen. U slučaju ksenobiotika, uticaji ozonizacije su bili različiti, u zavisnosti od primenjenog uglja, matriksa i supstance. Najizraženiji uticaj je kod alahlora,&nbsp; i to u negativnom smislu,<br />zbog pada efikasnosti uklanjanja, verovatno zbog kompeticije sa organskom materijom ili efekta solubilizacije. U nekim slučajevima, ali mnogo manje, taj efekat je primećen i kod trifluralina. Na oba komercijalna uglja primećen je pozitivan uticaj ozonizacije na uklanjanje atrazina, ali u različitim matriksima,&nbsp; pa se može spekulisati<br />pretpostavljanjem da dolazi do favorizovane raspodele u novim oblogama&nbsp; POM na uglju formiranim nakon ozonizacije koje su i dovoljno adsorbabilne, ali i sa dovoljno reaktivnim osobinama za asociranje sa polarnim supstancama, &scaron;to je delimično i potvrđeno rezultatima adsorpcione analize.&nbsp;&nbsp;</p> / <p>The focus of&nbsp; this doctoral thesis was the study of the sorption behavior of three herbicides which are on the list of priority substances according to Water Framework Directive (2000/60/EC). The aim&nbsp; was&nbsp; to obtain the&nbsp; data useful for prioritization on the basis of the&nbsp; new fundamental knowledge about (ad) sorption efficiency&nbsp; for the removal of these substances from the&nbsp; locally specific water matrices. Selected xenobiotics&nbsp; were&nbsp; differing&nbsp; in&nbsp; solubility, hydrophobicity, and donor-acceptor properties, which belong to different classes of compounds(trifluralin as herbicide, alachlor as chloracetamide herbicide and atrazine as triazine herbicide).&nbsp; In the first phase&nbsp; of the thesis&nbsp; characterization&nbsp; of sorbents and water matrices&nbsp; was performed. The aim of the second phase was the testing&nbsp; of&nbsp; the sorption and<br />desorption of organic xenobiotics in the sediments and organoclays. The equilibrium&nbsp; sorption parameters and removal efficiencies of herbicides were determined in different water matrices.&nbsp; In the synthetic matrix, trifluralin showed a higher sorption affinity onto tested sediments in comparison to the alachlor and atrazine. In the case of organoclays, sorption was mostly&nbsp; pronounced for trifluralin. Alachlor and atrazine have similar sorption capacities onto the TMA-K. For the TMA-B, the sorption was more pronounced for alachlor than atrazine. Depending on the natural water matrices,&nbsp; the highest&nbsp; K<sub>d</sub> values were obtained for trifluralin onto both sediments. The&nbsp; K<sub>d</sub> values for atrazine and alachlor were very similar or even greater for atrazine. In the case of organoclays, K<sub>d</sub> values increased with increasing log&nbsp; K<sub>OW</sub> values of herbicides onto TMA-K in both natural matrices. When it comes to TMA-B,&nbsp; K<sub>d&nbsp;</sub> valuesincreased with increasing log&nbsp; K<sub>OW</sub> values in&nbsp; the surface matrix for<br />C<sub>e</sub> = 0,05 mg/l and 0,5 mg/l, and in groundwater at the highest equilibrium&nbsp; concentration&nbsp; C<span id="cke_bm_506S" style="display: none;">&nbsp;</span><sub>e</sub><span id="cke_bm_506E" style="display: none;">&nbsp;</span>&nbsp; = 0,5 mg/l. TMA-B (K<sub>d</sub> = 10,5&nbsp; -&nbsp; 483 l/kg) and model&nbsp; sediment&nbsp; (kd= 16,4 to 761 l/kg) were the most efficient s<span id="cke_bm_507E" style="display: none;">&nbsp;</span>orbents. The absence of&nbsp; the&nbsp; clear linear correlation between&nbsp; K<sub>d</sub> and % TOC&nbsp; indicates the importance of the interaction of mineral phases and herbicides. Correlation between K<span id="cke_bm_513S" style="display: none;">&nbsp;</span><sub>d</sub><span id="cke_bm_513E" style="display: none;">&nbsp;</span> and K<sub>OW</sub> values did not existed in the case of sediments,&nbsp; contrary to the organoclays.&nbsp; Since K<span id="cke_bm_519S" style="display: none;">&nbsp;</span><sub>d</sub><span id="cke_bm_519E" style="display: none;">&nbsp;</span> /K<sub>oW</sub> ratios were the h<span id="cke_bm_520E" style="display: none;">&nbsp;</span><span id="cke_bm_514E" style="display: none;">&nbsp;</span>ighest for atrazine onto all sorbents, it&nbsp; was&nbsp; assumed that atrazine mostly participate in specific interactions due to its donor-acceptor properties. Regarding the&nbsp; influence of DOC on sorption, it was concluded that a comparison of sorbents efficiencies should be carried in&nbsp; native matrices as sorption coefficients vary depending on the concentration of pollutants, the type and content of DOC. Column&nbsp; experiments showed that atrazine and alachlor passed through the column of the sediment, while the trifluralin almost completely was adsorbed and in very low concentrations detected in the effluent which is in accordance with the results of the&nbsp; batch experiments.&nbsp; Estimated retardation factors of atrazine were higher in natural matrices (R<span id="cke_bm_525S" style="display: none;">&nbsp;</span><sub>d </sub><span id="cke_bm_525E" style="display: none;">&nbsp;</span>= 54 and R<sub>d</sub> = 55 in groundwater and surface water, respectively) than in&nbsp; the synthetic water (R<sub>d </sub>= 40<sub>). I</sub>n the case of alachlor, retardation factors were similar among water matrices (R<sub>d</sub> = 30-35). These results are in the opposition&nbsp; based on the xenobiotic hydrophilicity, and they could be the consequence of interaction with the organic matter&nbsp; present&nbsp; in the column tests, probably more than in the batch tests. Estimations of&nbsp; R<sub>d</sub> based on batch tests&nbsp; did not show an increase of R<sub>d</sub> values in natural matrices, in comparison to the synthetic matrix. More hydrophobic alachlor, in the circumstances of the sorbent matrix exerts similar&nbsp; (batch&nbsp; tests) or lower sorption (column tests) characteristics that indicate mobility through the first protective layer.<span id="cke_bm_526E" style="display: none;">&nbsp;</span> The third phase&nbsp; included herbicide adsorption tests onto powdered activated carbons. The adsorption kinetics was examined by determining the intraparticle mass transfer coefficients for herbicides in raw and ozonated natural water matrices. The removal efficiencies of herbicides for different powdered activated carbons were determined. Removal efficiencies were in different ranges depending on the selected carbon, water matrix and carbon dose. The highest removal efficiencies&nbsp; for commercial carbons (for carbon dose of 15&nbsp; mg/l)&nbsp; for&nbsp; alachlor were 95% and 76% in surface and groundwater, respectively. The highest&nbsp; removal of atrazine was&nbsp; 58% in surface water and 56% in groundwater. In thecase of trifluralin, removal efficiencies were&nbsp; 87% in surface water and 92% in groundwater. The removal efficiencies for the carbon with fine particles&nbsp; (usually&nbsp; used in combination with a membrane filtration)&nbsp; were greater. The removal of DOC&nbsp; &nbsp; by&nbsp; commercial carbons (at the dose of 15 mg/l) was less than 57% in the surface water and 47% in groundwater. A similar efficiency in DOC removal was achieved for the carbon with fine particles in both water matrices. Ozonation showed the expected &nbsp; negative influence on&nbsp; DOC&nbsp; removal efficiencies, more or less pronounced. In the case of xenobiotics, ozonation influence was different, depending on the applied carbon and xenobiotic. The most important negative influence was&nbsp; in the case of alachlor probably due to competition with organic matter or solubilization effect. The&nbsp; same, but less pronounced effect was observed for trifluralin. The positive influence of ozonation was observed in removal of atrazine&nbsp; by&nbsp; both commercial carbons but in &nbsp; different water matrices.&nbsp; One can speculate that it comes to the favorable distribution in new NOM coatings on carbons formed upon ozonation, which are sufficiently adsorbable, but with enough reactive qualities for association with polar substances, which is partly confirmed by the results of adsorption analysis.</p>
66

Ozonation and/or Coagulation - Ceramic Membrane Hybrid for Filtration of Impaired-Quality Source Waters

Ha, Changwon 09 1900 (has links)
When microfiltration (MF) and ultrafiltration (UF) membranes are applied for drinking water treatment/wastewater reuse, membrane fouling is an evitable problem, causing the loss of productivity over time. Polymeric membranes have been often reported to experience rapid and/or problematical fouling, restraining sustainable operation. Ceramic membranes can be effectively employed to treat impaired-quality source waters due to their inherent robustness in terms of physical and chemical stability. This research aimed to identify the effects of coagulation and/or ozonation on ceramic membrane filtration for seawater and wastewater (WW) effluent. Two different types of MF and UF ceramic membranes obtained by sintering (i.e., TAMI made of TiO2+ZrO2) and anodic oxidation process (i.e., AAO made of Al2O3) were employed for bench-scale tests. Precoagulation was shown to play an important role in both enhancing membrane filterability and natural organic matter (NOM) removal efficacy for treating a highorganic surface water. The most critical factors were found to be pH and coagulant dosage with the highest efficiency resulting under low pH and high coagulant dose. Due to the ozone-resistance nature of the ceramic membranes, preozonation allowed the ceramic membranes to be operated at higher flux, especially leading to significant flux improvement when treating seawater in the presence of calcium and magnesium. 4 Dissolved ozone in contact with the TAMI ceramic membrane surface accelerated the formation of hydroxyl (˙OH) radicals in WW effluent treatment. Flux restoration of both ceramic membranes, fouled with seawater and WW effluent, was efficiently achieved by high backwash (BW) pressure and ozone in chemically enhanced backwashing (CEB). Ceramic membranes exhibited a pH-dependent permeate flux while filtering WW effluent, showing reduced fouling with increased pH. On the other hand, for filtering seawater, differences in permeate flux between the two membranes was observed under basic pH conditions, showing that the TAMI membrane flux was stable regardless of changes in pH, while the AAO membrane flux was significantly decreased as pH increased to 10. Consequently, it is expected that ozone and/or coagulation prior to ceramic membrane filtration can play a significant role in treating impaired-quality source waters (e.g., seawater and WW effluent), leading to maintaining sustainable membrane flux in seawater pretreatment before reverse osmosis (RO) or water reuse applications.
67

Modeling Of Membrane Solute Mass Transfer In Ro/nf Membrane Systems

Zhao, Yu 01 January 2004 (has links)
Five articles describing the impact of surface characteristics, and development of mass transfer models for diffusion controlled membrane applications are published in this dissertation. Article 1 (Chapter 3) describes the impact of membrane surface characteristics and NOM on membrane performance for varying pretreatment and membranes during a field study. Surface charge, hydrophobicity and roughness varied significantly among the four membranes used in the study. Membrane surface characteristics, NOM and SUVA measurements were used to describe mass transfer in a low pressure RO integrated membrane system. Inorganic and organic solute and water mass transfer coefficients were systematically investigated for dependence on membrane surface properties and NOM mass loading. Inorganic MTCs were accurately described by a Gaussian distribution curve. Water productivity, NOM rejection and inorganic rejection increased as membrane surface charge and NOM loading increased. Inorganic MTCs were also correlated to surface hydrophobicity and surface roughness. The permeability change of identical membranes was related to NOM loading, hydrophobicity and roughness. Organic fouling as measured by water, organic and inorganic mass transfer was less for membranes with higher hydrophilicity and roughness. Article 2 (Chapter 4) describes the development of a diffusion controlled solute mass transfer model to assess membrane performance over time. The changing mass transfer characteristics of four low-pressure reverse osmosis (LPRO) membranes was correlated to feed stream water quality in a 2000 hour pilot study. Solute mass transfer coefficients (MTCs) were correlated to initial solute MTCs, solute charge, feed water temperature, monochloramine loading and organic loading (UV254). The model can be used to predict cleaning frequency, permeate water quality and sensitivity of permeate water quality to variation of temperature, organic and monochloramine mass loading. Article 3 (Chapter 5) describes a comparison of the long standing method of assessing membrane performance (ASTM D 45160 and another approach using mass transfer coefficients (MTCs) from the homogenous solution diffusion model (HSDM) using a common data set, water productivity and standardized salt passage. Both methods were shown to provide identical assessments of water productivity, however different assessments of salt passage. ASTM D 4516 salt passage is normalized for pressure and concentration and does not show the effects of flux, recovery, temperature or specific foulants on salt passage. However the MTC HSDM method is shown to consider all those effects and can be easily used to predict membrane performance at different sites and times of operation, whereas ASTM D 45160 can not. The HSDM MTC method of membrane evaluation is more versatile for assessment of membrane performance at varying sites and changing operational conditions. Article 4 (Chapter 6) describes the development of a fully integrated membrane mass transfer model that considers concentration, recovery and osmotic pressure for prediction of permeate water quality and required feed stream pressures. Osmotic pressure is incorporated into the model using correction coefficients that are calculated from boundary conditions determined from stream osmotic pressures of the feed and concentrate streams. Comparison to homogenous solution diffusion model (HSDM) with and without consideration of osmotic pressure and verification of IOPM using independently developed data from full and pilot scale plants is presented. The numerical simulation and statistical assessment show that osmotic pressure corrected models are superior to none-osmotic pressure corrected models, and that IOPM improves model predictability. Article 5 (Chapter 7) describes the development and comparison of a modified solution diffusion model and two newly developed artificial neural network models to existing mechanistic or empirical models that predict finished water quality for diffusion controlled membranes, which are generally restricted to specific solute MTCs that are site and stage specific. These models compensate for the effects of system flux, recovery and feed water quality on solute MTC and predict permeate water quality more accurately than existing models.
68

Natural organic matter (NOM) and turbidity removal by plant-based coagulants: A review

Okoro, B. U., Sharifi, S., Jesson, M. A., Bridgeman, John 21 October 2021 (has links)
yes / NOM deteriorates water quality by forming taste, clarification, colour, and odour problems. It also increases coagulant and chlorine consumption which can initiate disinfection by-products harmful to human health. The coagulation-flocculation (CF) technique is an established method commonly employed to remove NOM in water treatment. Plant-based coagulant products (PCPs) derived from plants like the Moringa oleifera (MO) Strychnos potatorum Linn and Opuntia ficus indica, have been studied and proposed as sustainable alternatives to chemical coagulant, like, aluminium sulphate due to their abundant availability, low cost, low sludge volume and disposal cost, and biodegradability. This review paper provides an overview of the most widely studied plant-based coagulants and discusses their NOM and turbidity removal. It investigates recent analytical tools applied in their characterisation and floc morphological studies. The paper also investigates the effects of operating parameters such as coagulant dose, temperature, and pH, on NOM and turbidity removal. It also reviews up-to-date PCPs biophysical properties and CF mechanism and examines the efficiency of their extraction methods in reducing NOM. Finally, it discusses and suggests ways to overcome commercialisation draw-back caused by nutrient addition.
69

Bench-Scale Assessment of Low Pressure Membrane Fouling: Characterization and Examination the Role of Organic Nitrogen Compounds

Nguyen, Anh Hai 01 September 2010 (has links)
The primary goal of this research was to improve understanding of the fouling of low pressure hollow fiber membranes used in drinking water treatment. The major difference of this study compared to other reported studies was the use of a hollow fiber membrane module at operating conditions mimicking those of full-scale practice. Two poly(vinylidene-fluoroethylene) based hollow fiber membranes (A and B) were tested. Different types of fouling indices (total, hydraulic irreversible, chemical irreversible) developed based on a resistance in series model were used to assess membrane performance. Data from bench-scale and full-scale plants were compared to validate the use of fouling indices. The impact of dissolved organic nitrogen (DON) on membrane fouling was demonstrated with model waters containing humic substances and several model organic nitrogen compounds. Three different natural water sources normalized to the same organic content were tested. Fouling indices determined from the resistance in series model approach were more applicable for natural waters than for model waters. Fouling was proportional to throughput for both raw and pretreated water and at different flux rates. Pretreatment (coagulation) reduced hydraulic irreversible fouling. Most fouling was reversed by hydraulic and chemical cleaning. Specific flux and fouling indices of the bench-scale system were higher than those of the full-scale system but the fouling index ratios were comparable suggesting a similar fouling nature. A minimum of a few days of testing is recommended for longer-term membrane performance assessment. The impact of high DON concentration on membrane fouling was insignificant. Membrane fouling was dependant on foulant properties other than, or in addition to, molecular size and the DON/DOC ratio. With three different natural water sources normalized to a similar organic content, membrane fouling was specific to membrane type and water source. High initial total and hydraulic irreversible fouling rates did not lead to high chemical irreversible fouling rates. It is not possible to generalize the impact of different water sources on membrane fouling. Membrane surface anlyses showed that hydraulically irreversible organic foulants were detected as mostly hydrocarbons/polysaccharides, humic substances and peptide/protein. Humic substances and peptide/protein were found to be organic foulants regardless of their molecular weight and origin. Chemical cleaning with chlorine solution was effective in removing all inorganic foulants and most organic foulants.
70

Characterizing Variability in Ohio River NOM and Validating Reconstituted Freeze-Dried NOM as a Surrogate for its Aqueous Source

Rossman, Paul D. 13 October 2014 (has links)
No description available.

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