Relevant bibliographies by topics / Extraction et purification

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  1. Journal articles
  2. Dissertations / Theses
  3. Book chapters
  4. Conference papers

Academic literature on the topic 'Extraction et purification'

Author: Grafiati
Published: 4 June 2021
Last updated: 17 February 2022

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Journal articles on the topic "Extraction et purification"

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Leboukh, Mourad, and Saoudi Aouadi. "Extraction et Purification des Galactomannanes A Partir des Graines de Gleditsia Triacanthos L. = Extraction and Purification of Galactmannans from Gleditsia Triacanthos L. Seeds." Algerian Journal of Arid Environment 7, no. 2 (December 2017): 72–77. http://dx.doi.org/10.12816/0046100.

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Li, Cui Ping, and Ping Lv. "Research on Separation and Purification of Total Anthraquinones in Radix et Rhizoma Rhei by D301 Macroporous Resin." Advanced Materials Research 1092-1093 (March 2015): 630–34. http://dx.doi.org/10.4028/www.scientific.net/amr.1092-1093.630.

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D301 resin was used to separate and purify total anthraquinones in Radix et Rhizoma Rhei. It was found that the optimized dynamic adsorption conditions is pH7.0, flow velocity of 1.0 BV/h and extracting solution with concentration of 0.3g/mL and optimized dynamic elution conditions is hydrochloric acid with concentration of 0.15mol/L, 75% ethanol, and flow velocity of 1.0 BV/h. Under the above conditions,the average adsorption rate and desorption rate are respectively 89.75% and 91.15%, indicating that extraction efficiency of total anthracenone of emodin is relatively high and that the technology enjoys strong stability.
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Jiang, Ping, Qian Zhang, Yajie Zhao, Jia Xiong, Fei Wang, Ting Zhang, and Chenmeng Zhang. "Extraction, Purification, and Biological Activities of Polysaccharides from Branches and Leaves of Taxus cuspidata S. et Z." Molecules 24, no. 16 (August 13, 2019): 2926. http://dx.doi.org/10.3390/molecules24162926.

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Taxus cuspidata S. et Z. is an excellent natural source of bioactive polysaccharides and has various biological activities. The objective of this study was to evaluate the effect of antidiabetic and antitumor activities of polysaccharides from Taxus cuspidata branches and leaves (TCBL) and to determine the optimum extraction technology of TCBL using a low-temperature and high-efficiency enzyme and ultrasound-assisted coupled extraction (EUCE) method. Optimal technology parameters were determined as follows: an extraction temperature of 51 °C, an extraction time of 33 min, a ratio of material to liquid of 1:19 (g:mL), and an enzyme concentration of 0.10 mg·mL−1. Under the optimized conditions, the polysaccharide yield from TCBL obtained by EUCE was 4.78% ± 0.18%. The four purified polysaccharides (Pe1, Pe2, Pe3, Pe4) from TCBL are mainly composed of arabinose, galactose, glucose, a small amount of xylose, and mannose. This composition was assessed by HPIC analysis. The antidiabetic activity and antitumor activity of polysaccharides from TCBL were assayed in vitro. Among the four purified polysaccharides from TCBL, purified Pe4 had the highest inhibitory capacity against α-glucosidase, and its IC50 value was 123.0 µg·mL−1. Pe1 had the highest antitumor capacity against MCF7 cells and HepG2 cells, with IC50 values of 169.0 and 132.0 µg·mL−1. Pe4 had the highest antitumor effect on human cervical cancer cells (Hela), and its IC50 value was 89.9 µg·mL−1. Pe4 polysaccharide demonstrated a good α-glucosidase inhibitory activity and antitumor capacity against Hela cells. Therefore, Pe4 polysaccharide from TCBL is a beneficial source of potential inhibitors of type II diabetes and human cervical cancer activity.
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Mészáros, Marianna, Ingo Leya, Beda A. Hofmann, and Sönke Szidat. "Current Performance and Preliminary Results of a New 14C Extraction Line for Meteorites at the University of Bern." Radiocarbon 60, no. 2 (November 16, 2017): 601–15. http://dx.doi.org/10.1017/rdc.2017.114.

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AbstractHere, we introduce a new radiocarbon (14C) extraction line operating at the University of Bern, which was designed and built for the extraction of in situ 14C from meteorites. With this system, we achieved two important developments compared to other systems. First, using the MICADAS gas-interface system, 14C can directly be measured from the collected CO2 gas, i.e., without graphitization of the sample. Second, meteorite sample masses as low as ~0.05 g can be used for high precision and reproducibility. Prior to extraction in an oxygen atmosphere held at a pressure of ~20–30 mbar in an iridium crucible at 1600°C for 40 min, samples were preheated for 1 h in a constant oxygen flow at 500°C and continuous pumping. Gas purification followed the method described previously (e.g., Hippe et al. 2009). While the blank levels for preheated samples are low (<2×104 14C atoms), the blanks for non-preheated samples are high, therefore those results cannot be used. We also report preliminary results for the L-chondrite JaH 073. The terrestrial age of 17.7±0.4 ka is in good agreement with previous results for the same sample of this meteorite, confirming that the extraction line, the gas purification system, and the AMS measurements are all reliable.
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Gao, Dawei, Na Li, Qingwang Li, Jian Li, Zengsheng Han, Yusheng Fan, and Zhiwei Liu. "Study of the extraction, purification and antidiabetic potential of ursolic acid fromCornus officinalis Sieb. et Zucc." Therapy 5, no. 5 (September 2008): 697–705. http://dx.doi.org/10.2217/14750708.5.5.697.

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Bina, Fatemeh, Zabihollah Zamani, Vahideh Nazeri, and Daryush Talei. "Comparative Different DNA Isolation Protocols from Ziziphus spina-christi (L.) Leaves through RAPD and ISSR Markers." Journal of Agricultural Science 8, no. 6 (May 10, 2016): 49. http://dx.doi.org/10.5539/jas.v8n6p49.

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<p>Genomic analysis of plants relies on high quantity and quality of pure DNA. Extraction and purification of DNA from woody and medicinal plants, such as fruit trees present a great challenge due to accumulation of a large amount of co-purify with DNA, including polysaccharides, polyphenols and proteins. Therefore, it is necessary to optimize the extraction protocols to reduce these compounds to the lowest level. A study was conducted to compare six DNA extraction and precipitation methods for genomic analysis in<em> Ziziphus spina-christi</em> (L.) plant tissues. The results showed significant differences in DNA contents among the six methods. Quantity and quality of extracted genomic DNAs were compared by employing the spectrophotometer, Nano-Drop, agarose gel electrophoresis, digestion by restriction enzymes and polymerase chain reaction (PCR) methods and molecular marker such as RAPD and ISSR. The method of Vroh Bi et al., provided the best results (208.89 ng/μL) in terms of quantity and quality of DNA, and Doyle and Doyle method as second method for leaves sample were chosen. According to the results, the method of Bi et al. is recommended for DNA extraction from plant tissues having high level of polysaccharides and phenol compounds.</p>
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Thinh, Du Phuc, Tang Thi Kim Hong, and Huynh Van Biet. "OPTIMIZATION OF THE DNA EXTRACTION PROTOCOL FROM WOOD SAMPLE BY RESPONSE SURFACE METHODS – CENTRAL COMPOSITE DESIGN." Vietnam Journal of Science and Technology 55, no. 6 (December 11, 2017): 725. http://dx.doi.org/10.15625/2525-2518/55/6/9724.

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The DNA extraction is one of the first steps and plays animportant role in study on genome of any species on earth. Depending on the purpose and object of study, DNA can be extracted from various tissues.For plants, DNA is usually extracted from the leaves, seeds and young buds, in which these tissues are the best DNA source and can be extracted easily. However, the collection of sample from mature trees, which are generally tall, isdifficult and need more facilities. Consequently, it leads to be limited for the study scope.The proposed solutionis to use a wood tissue instead ofthe leaves, seeds and young due to they are easily collected. The problem is very difficult to extract high quality DNA from the wood tissue (Verbylaite et al., 2010). However, if the extraction of DNA from wood tissue would besuccessful, it would open up many research directions and could turn techniques that seemed unfeasible before into the effective solution. Extracting and analyzing DNA from dried wood and processed wood could be developed to explore the possibility of identifying the species and theirorigin. This could be greatly useful for determining the legality of wood log and wood products, and for deterring trade in illegal wood products (Tsumura et al.,2011). Currently, there are some commercialized kits, enabling DNA extraction from wood more easily,e.g. DNeasy Plant Mini Kit (Qiagen), Nucleospin Plant II (Macherey-Nagel), Genomic DNA Purification Kit (Fermentas) and innuPREP Plant DNA Kit (Analytik Jena). However, the commercial Kitsare expensive. Meanwhile, there are some cheaper methods, applying for DNA extraction from wood successfully, such as SDS method (Edwards et al.,1991; Goodwin and Lee, 1993), protein precipitation protocol (Dellaporta et al., 1983; Fang et al., 1992), especially CTAB method, obtaining with a high DNA concentration (Doyle J and Doyle H., 1987). The DNA extracted by CTAB protocol is less pure; however, they are still suitable to use in molecular biology. The objective of this work was to optimize the conditions of CTAB protocol for DNA extraction from wood. The two parameters centrifugation time and volume ratio of isopropanol to solutions containing DNA that affect the yield and quality DNA were explored using the response surface methodology (RSM). The central composite design (CCD) was used to obtain the experimental design matrix. This approach has limited number of actual experiments performed where as allowing probing into possible interaction between these parameters studied and their effect on quantity and quality DNA.
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Nafis, A., A. Azmani, B. Oubaha, L. Hassani, T. Niedermeyer, and M. Barakate. "Extraction et purification des antifongiques non polyéniques de la souche Streptomyces sp. Z26 isolée des écosystèmes Marocains." Journal de Mycologie Médicale 26, no. 2 (June 2016): e13-e14. http://dx.doi.org/10.1016/j.mycmed.2016.04.032.

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Jiang, Ping, Yajie Zhao, Jia Xiong, Fei Wang, Lujie Xiao, Siyao Bao, and Xiangdong Yu. "Extraction, purification, and biological activities of flavonoids from branches and leaves of Taxus cuspidata S. et Z." BioResources 16, no. 2 (February 19, 2021): 2655–82. http://dx.doi.org/10.15376/biores.16.2.2655-2682.

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The optimal operational and process parameters were determined for the enzymatic hydrolysis and ultrasound-assisted extraction (EHUE) method of flavonoids extracted from Taxus cuspidata branches and leaves (TCBL), and the biological activity of obtained flavonoids was evaluated. According to single factor and central composite design experiments, the optimum key experimental parameters for EHUE were that pectinase enzyme concentration was 0.10 mg·mL-1, enzymatic hydrolysis temperature was 48 °C, and enzymolysis time was 39 min. The yield of flavonoids from TCBL under the optimized conditions was 5.23% ± 0.18%. Four purified flavonoid compounds from TCBL extract were identified as 1) (E)-1-methoxy-2-O-(p-coumaroyl)-myo-inositol, 2) catechin, 3) epicatechin, and 4) quercetin-3-O-glucoside. Among the 4 compounds, compounds 2 and 3 showed higher antioxidant capacities, α-amylase, and α-glucosidase inhibitory activities. The statistical analysis showed that epicatechin and catechin were potent antioxidants and active agents for inhibiting type II diabetes. In addition, all 4 compounds exerted clear antitumor activity against MCF-7, Hela, and HepG2 cells. Especially, compound 4 had highest antitumor capacity against MCF-7 and Hela, while compound 1 was best at suppressing the proliferation of HepG2 cells.
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Kone, Hervé Cédessia Kéassemon, Nicaise Tetchi Akedrin, Vama Etienne Tia, Fatou Bayoko, and Lacina Fanlégué Coulibaly. "Qualités morpho-physiologiques et évaluation du comportement germinatif des graines du théier des savanes (Lippia multiflora Moldenke)." International Journal of Biological and Chemical Sciences 14, no. 6 (October 6, 2020): 1988–98. http://dx.doi.org/10.4314/ijbcs.v14i6.5.

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La domestication de Lippia multiflora, plantes aux multiples vertus en pharmacopée et médecine est un enjeu de taille en Côte d’Ivoire. Cependant, l’insuffisance de semences, due au faible taux de germination des graines, limite l’extension de sa culture. La présente étude avait pour objectif l’extraction, la purification et la caractérisation morpho-physiologique des graines de Lippia multiflora Moldenke (Verbenaceae). Il s’agissait plus spécifiquement de déterminer la pureté spécifique, le nombre de graines par unité de masse, le diamètre moyen et le taux d’humidité ; le taux de germination des graines de L. multiflora. Aussi, il s’est agi d’étudier l’impact du milieu sur le pouvoir germinatif des graines et de faire un suivi post-germination des plants en milieu réel. Après extraction des graines, des mesures physiques et des tests de germination ont permis de déterminer les caractéristiques morpho-physiologiques de celles-ci. L’étude a montré que le lot de graine étudié a une pureté spécifique de 70%, les graines ont un diamètre moyen de 0,34± 0.1 mm, une teneur en eau de 14±5.4 % et un taux de germination de 42,25%. Les tests de germination après un séjour prolongé dans divers milieux, révèlent qu’un milieu réfrigéré (7° C) confère une plus longue viabilité aux graines. Le suivi post-germination au champ montre une évolution régulière de la hauteur des plants, passant en moyenne de 2,58 cm à 8,8 cm au bout de 3 mois. Sur la même période, le nombre moyen de feuille varie de 4,03 à 21.Mots clés : Lippia multiflora, graine, caractérisation, germination, suivi post-germination. English Title: Morpho-physiological qualities and evaluation of the germination behavior of seeds of the savannah tea tree (Lippia multiflora Moldenke)The domestication of Lippia multiflora, plants with multiple virtues in pharmacopoeia and medicine is a major challenge in Côte d'Ivoire. However, the lack of seed, due to the low germination rate, limits the extension of its cultivation. The purpose of this study was the extraction, purification and morpho-physiological characterization of the seeds of Lippia multiflora Moldenke (Verbenaceae). More specifically, it involved determining the specific purity, the number of seeds per unit mass, the average diameter and the humidity rate; the germination rate of L. multiflora seeds. Also, it was a question of studying the impact of the environment on the germination power of seeds and of making a post-germination follow-up of the plants in real environment. After the seeds extraction, physical measurements and germination tests were carried out to determine the morpho-physiological characteristics. Results showed that the seed lot studied has a specific purity of 70%, an average diameter of 0.34 0.1 mm, a water content of 14 5.4% and a germination rate of 42.25%. Germination tests after a prolonged stay in various environments reveal that a refrigerated area (7 °C) confers a longer viability to the seeds. Post-germination monitoring in the field shows a steady increase in plant height from an average of 2.58 cm to 8.8 cm after 3 months. Over the same period, the average number of sheets varies from 4.03 to 21.Keywords: Lippia multiflora, seed, characterization, germination, post-germination monitoring.
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Dissertations / Theses on the topic "Extraction et purification"

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Belghith, Hafedh. "Production et extraction-purification d'une alcool oxydase : réalisation et développement d'un capteur à alcools." Compiègne, 1985. http://www.theses.fr/1985COMPI211.

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Cliche, Simon. "Extraction et purification de collagène natif provenant de la peau de poulet." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0029/MQ67436.pdf.

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Haj, Youssef Mouna. "Extraction liquide - liquide et extraction par émulsions appliquées à la purification de l'acide phosphorique vis-à-vis du cadmium." Châtenay-Malabry, Ecole centrale de Paris, 2008. http://www.theses.fr/2008ECAP1108.

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Dans cette thèse nous nous intéressons à la purification de l'acide phophorique par extraction du cadmium. Deux techniques ont été utilisées : l'Extraction liquide liquide et l'Extraction par membrane liquide émulsionnée. Notre apport par rapport à la première technique consiste en l'utilisation d'un nouveau couple extractant-desextractant qui sont respectivement l'acide di (2) éthylheryl dithiophosphorique synthétisé au sein du laboratioire et le (HCl 4M ou HCl 1M+NaCl 3M). Les essais expérimentaux réalisés ont permis de montrer l'efficacité de ce nouveau couple extractant-desextractant et de déduire les mécanisme d'extraction et de désextraction. L'étude de l'Extraction par membrane liquide émulsionnée nous a permis de démontrer expérimentalement que cette technique permet d'extraire la même quantité de cadmium tout en utilisant moins de D2EHDTPA. En optimisant la formulation de l'émulsion, nous avons montré qu'on peut atteindre un facteur de concentration élevé. Ceci signifie qu'on peut concentrer le cadmium dans un volume très réduit de la phase aqueuse de l'émulsion, ce qui est intéressant de point de vue de protection de l'environnement. L'étude de ces deux techniques d'extraction est accompagnée par l'étude des tests de faisabilité de procédés industriels. Le procédé retenu est sous forme d'un étage en mélangeur décanteur. Le pilote proposé en extraction liquide-liquide comporte deux étages d'extraction dont la performance de chacun est de 99% et 6 étages en désextraction. Avec un tel montage on a pu concentrer le cadmium 50 fois et ceci en partant d'une concentration initiale de cadmium égale à 40 mg. L-1.
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Campos, Assunção Mariana. "Etude physicochimique et formulation d'un nouveau solvant d'extraction pour la purification de l'acide phosphorique." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066045/document.

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Cette thèse avait pour objectif de développer de nouveaux systèmes d’extraction liquide-liquide compatibles avec le procédé Prayon pour la purification de l’acide phosphorique produit par voie humide. Une étude bibliographique complète des solvants d’extraction étudiés dans la littérature pour l’extraction liquide-liquide de l’acide phosphorique nous a permis d’identifier des candidats potentiellement intéressants. Une étude approfondie des propriétés d’extraction de ces systèmes et de leur sélectivité vis-à-vis des espèces métalliques nous a finalement permis de nous focaliser par la suite sur trois solvants d’extraction : le dibutyl éther (DBE), le diisobutyl carbinol (DiBC) dilué dans le diisopropyl éther (DiPE) et la Fentamine T0810 (ATS) dilué dans le DiPE. La formulation de ces mélanges a ensuite été optimisée en veillant à étudier le comportement de ces systèmes à chaque étape du procédé d’extraction liquide-liquide, c’est à dire l’extraction, la désextraction et le lavage. Cette étude a également permis de fixer les conditions opératoires optimales, notamment le rapport des volumes des phases. Au cours de cette étude, des phénomènes complexes de transitions de phases réversibles de la phase organique de monophasique vers biphasique (formation de troisième phase) et biphasique vers monophasique (retour à une phase organique unique) ont été mis en évidences expérimentalement. Pour finir, un modèle physicochimique d’extraction fondé sur des bilans de masse a été développé. Ce modèle s’avère très utile pour décrire l’extraction de l’acide phosphorique et de l’eau et la variation des volumes des phases au cours de l’extraction
This PhD thesis was focused on the development of new extraction systems to purify phosphoric acid from wet phosphoric acid (WPA). The new system should be respectful of the current Prayon’s process flowsheet designed for the use of the mixture tri-n-butyl phosphate(TBP) and diisopropyl ether (DiPE) as extraction solvent. Firstly, extractants exhibiting different structures and functional groups were screened in order to assess their efficiency and selectivity towards phosphoric acid. Three new promising extraction systems were identified: diisobutyl ether (DBE), diisocarbinol (DiBC) in DiPE, and Fentamine T0810 (ATS) in DiPE. Secondly, our effort was directed to the comprehension of the physico-chemical phenomena involved in the extraction of phosphoric acid by the mixture TBP/DiPE at first, and enriched to describe the other systems studied later. Finally, a simulation model describing the solvent extraction of phosphoric acid by the solvent currently employed by Prayon is presented. This model accounts for the significant volume variation during the extraction of phosphoric acid and allows performing optimizations of extraction parameters even at very high phosphoric acid concentrations (6-14M)
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Papet, Nicolle Marie-Pierre. "Extraction et purification de glycosides à activité cytokinine dans le germe de blé." Orléans, 1989. http://www.theses.fr/1989ORLE2023.

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Notre travail repose principalement sur la définition d'un protocole d'extraction et de purification de régulateurs de croissance glycosylés à activité cytokinine, dans le germe de blé. La mise en évidence d'une telle activité dans les extraits hydro-alcooliques de pH voisin de la neutralité est révélée dans quatre tests biologiques: cotylédons de radis, tissus de soja, embryons d'Agrostemma githago, cotylédons de concombres. La présence de galactosidases dans ces extraits susceptibles de dégrader les composes glycosyles attendus nous a amené à sélectionner un inhibiteur enzymatique spécifique, l'iodoacétamide. Dans ces conditions, un schéma original d'extraction et de purification des produits actifs est décrit. Des composes présentant une forte activité cytokinine sont ainsi isolés. Une étude structurale préliminaire révèle une structure tétra ou pentasaccharidique constituée de résidus de glucose et de xylose associés à un aglycone aromatique
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Herzi, Nejia. "Extraction et purification de substances naturelles : comparaison de l’extraction au CO2-supercritique et des techniques conventionnelles." Phd thesis, Toulouse, INPT, 2013. http://oatao.univ-toulouse.fr/9437/1/herzi.pdf.

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Ce travail concerne l'extraction de substances naturelles d'origine végétale en utilisant des procédés « verts » tels que l'extraction au CO2 supercritique (CO2-SC, de 90 à 1000 bar) et l'extraction à l'eau sub-critique (SWE). Ces procédés sont une alternative à l'hydrodistillation (HD) et l'extraction par solvant (SE) traditionnellement utilisés dans l'industrie des produits naturels. La majorité du travail a été réalisée sur l'espèce Tetraclinis articulata où les performances des procédés, CO2-SC , HD, SWE et SE, ont été optimisées puis comparées en termes de rendement, composition chimique, durée…, et en particulier activité antioxydante des extraits (évaluée par les tests ABTS+ and DPPH). La plus forte activité antioxydente a été mise en évidence pour les extraits CO2-SC, ceci étant très probablement dû à une moindre dégradation thermique, comme l'a indiqué la comparaison des compositions chimiques. La CO2-SC basse pression (90 bar) a permis d'obtenir un extrait de bonne qualité et, pour ce cas, une modélisation a été proposée pour comprendre et identifier le mécanisme limitant qui s'est avéré être l'équilibre solide-fluide. La modélisation de l'hydrodistillation a également été proposée, basée sur le modèle de Sovová . Ensuite, l'approche a été étendue à d'autres plantes : Eucalyptus cinerea, Eucalyptus Camaldulensis, Cypres sempervirens et callitris. ABSTRACT : This work has dealt with extraction of natural substances from plants using « green » processes such as supercritical CO2 extraction (CO2-SC from 90 to 1000 bar) and extraction with subcritical water (SWE). These processes are an alternative to hydrodistillation (HD) and solvent extraction (SE) traditionally used in the natural products industry. Main part of the work was done on the species Tetraclinis articulata, and performance of the different processes, CO2-SC, HD,SWE and SE, were optimized and compared in terms of yield, chemical composition, duration ... and especially antioxidant activity of extracts (assessed by the ABTS+ and DPPH tests). CO2-SC extracts exhibited the strongest antioxidant activity and comparison of chemical compositions of the different extracts indicated that this is very probably due to lower thermal degradation of active molecules. For low pressure CO2-SC (90 bar), a model was proposed to understand and identify the limiting mechanism that proved to be solid-fluid equilibrium. For hydrodistillation, modelling, based on the Sovová 's model was also proposed. Then, the approach was extended to other plants: Eucalyptus cinerea and Eucalyptus camaldulensis, Cypres sempervirens and Callitris.
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Alhage, Josiane. "Valorisation des plantes médicinales du Liban ; extraction, purification et détermination structurale de molécules bioactives." Rennes, Ecole nationale supérieure de chimie, 2018. http://www.theses.fr/2018ENCR0052.

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L’étude des plantes médicinales représente une stratégie universelle pour la découverte de nouveaux médicaments car elle permet d’acce��der à une source importante de molécules à potentiel thérapeutique dans le cas de nombreuses pathologies. Pour valoriser les vertus thérapeutiques des plantes médicinales locales, nous nous sommes intéressés à l’étude de deux plantes abondantes au Liban, la C. Retrorsa et la C. Villosa. Dans la présente étude, nous avons choisi d’évaluer les activités antioxydante, antimicrobienne, antidiabétique, anti inflammatoire, hémolytique et cytotoxique des extraits bruts macérés (dichlorométhaniques, méthanoliques et aqueux) des différentes parties de ces deux plantes. Les extraits dichlorométhaniques et méthanoliques des tiges et des feuilles de C. Retrorsa montrent des effets cytotoxiques importants après un traitement de 48 heures à 2 mg/mL. Les extraits méthanoliques possèdent une activité anti-radicalaire élevée pour une concentration de 1 mg/mL. Seuls les extraits dichlorométhaniques des feuilles et des fleurs de cette espèce inhibent la croissance de A. Baumanii et C. Albicans pour une concentration de 2 mg/mL. Les extraits dichlorométhanique et méthanolique des tiges exercent une inhibition modérée de l'enzyme α-glucosidase à 2 mg/mL. Tous ces extraits se sont révélés inactifs vis-à-vis de l’inhibition de la PLA2 du venin d’abeille. Concernant C. Villosa, les résultats montrent que les extraits méthanoliques de toutes les parties possèdent des activités antiradicalaires intéressantes similaires à celle de la vitamine C. L’extrait aqueux des tiges montre une activité hémolytique modérée de 35% à 10 mg/mL suivi par l’extrait dichlorométhanique des feuilles qui conduit à une hémolyse de 25 % à cette même concentration. L’extrait méthanolique des tiges inhibe la croissance de K. Pneumoniae de 16 mm pour une concentration de 1 mg/mL. De même, cet extrait méthanolique des tiges possède une activité antidiabétique en inhibant l’activité de l'α-glucosidase de 39% à une concentration de 2 mg/mL. L’évaluation de ces extraits pour leur activité cytotoxique sur la lignée cellulaire HeLa met en évidence des effets antiprolifératifs remarquables pour les extraits méthanolique des feuilles et dichlorométhanique des tiges. Concernant l’activité anti-inflammatoire, les extraits n’ont montré aucune activité inhibitrice de la phospholipase du venin d’abeille. Les fractionnements des extraits bioactifs, dichlorométhanique et méthanolique des tiges de C. Villosa, par les différentes méthodes chromatographiques (LC, CCM préparative), aboutissent à la purification de cinq produits. La caractérisation des structures chimiques de ces composés via l’utilisation de méthodes spectroscopiques (RMN, HR-MS) a permis d’identifier la basalethanoïde B, le β-sitostérol et le stigmastérol, la chrysine-7- O-β-D-glucopyranoside, la chrysine 7-(6′′-O-acétyl)-O-β-Dglucopyranoside et la calythropsine, isolés pour la première fois à partir de l’espèce C. Villosa. L’évaluation des activités biologiques in vitro de ces produits purifiés montre que : - la calythropsine possède des activités cytotoxique, antioxydante et antidiabétique intéressantes (inhibition de 99% du taux de la prolifération après 48 heures de traitement et de 100% du radical DPPH. à 0. 1 mg/mL, et de 90% de l’α-glucosidase pour une concentration de 0. 3 mg/mL). - la chrysine 7-O-β-D-glucopyranoside inhibe la croissance de A. Baumanii de 10 mm à une concentration de 1 μg/mL, et l’activité de l’enzyme α-glucosidase de 93% à 0. 1 mg/mL
The study of medicinal plants represents a universal strategy for the discovery of new drugs as they constitute an important source of biologically active molecules used for the treatment of various diseases. To highlight the therapeutic virtues of local medicinal plants, we are interested in the study of two abundant plants in Lebanon: C. Retrorsa, and C. Villosa. In the present study, we undertook to evaluate the antioxidant, antimicrobial, antidiabetic, anti-inflammatory, hemolytic and cytotoxic activities of the macerated (dichloromethane, methanol and aqueous) crude extracts of the different parts of these two plants. The dichloromethane and methanol extracts of the stems and leaves of C. Retrorsa show significant cytotoxic effects after 48 hours of treatment at 2 mg/mL. The methanol extracts have a high anti-radical activity at a concentration of 1 mg/mL. Only the leaf and the flower dichloromethane extracts of this species inhibit the growth of A. Baumanii and C. Albicans at 2 mg/mL. The stem dichloromethane and methanol extracts show a moderate inhibition of the α-glucosidase enzyme at 2 mg/mL. All these extracts are found to be inactive for the inhibition of PLA2 of bee venom. For C. Villosa the results display that the methanol extracts have interesting anti radical activities similar to vitamin C. The stem aqueous extract possesses a moderate hemolytic activity of 35% at 10 mg/mL followed by the leaf dichloromethane extract revealing a hemolysis of 25% at the same concentration. The stem methanol extract inhibits by 16 mm the growth of K. Pneumoniae at 1 mg/mL. Furthermore, this extract exhibits an antidiabetic activity (inhibits the activity of α-glucosidase by 39% for a concentration of 2 mg/mL). The evaluation of these extracts for their cytotoxic activity on HeLa cell line shows that the leaf methanol and the stem dichloromethane extracts have remarkable anti proliferative effects. Regarding the anti-inflammatory activity, all these extracts do not have inhibitory activity of the phospholipase of bee venom. The purification of the stem dichloromethane and methanol extracts of C. Villosa, by different chromatographic methods (LC, preparative TLC) yielded five compounds. The characterization of the structures of these compounds by the different spectroscopic methods (NMR, HR-MS) made it possible to identify basalethanoïd B, β-sitosterol and stigmasterol, chrysin-7-O-β-D-glucopyranoside, chrysin 7-(6′′-O-acetyl)-O-β-D-glucopyranoside and calythropsin, isolated for the first time from C. Villosa. The evaluation of these products in vitro biological activities shows that: - Calythropsin exhibits attractive cytotoxic, antioxidant and antidiabetic activities (99% inhibition of the proliferation rate after 48 hours of treatment and 100% of the DPPH radical at 0. 1 mg/mL, and 90% of the α- glucosidase for a concentration of 0. 3 mg/mL). - Chrysin 7-O-β-D-glucopyranoside inhibits by 10 mm the growth of A. Baumanii at a concentration of 1 μg/mL, and by 93% the activity of the α-glucosidase enzyme at 0. 1 mg/mL. Key-words: C. Retrorsa, C. Villosa, Bioactivities, Secondary metabolites, Structural studies
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8

Nait-Si, Youssef. "Extraction, purification, comportement chimique de l'hypéricine et de la pseudohypéricine du millepertuis (hypericum perforatum)." Aix-Marseille 3, 2002. http://www.theses.fr/2002AIX30073.

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Le millepertuis est une plante médicinale à activités multiples qui contient deux caractéristiques, l'hypéricine et la pseudohypéricine, aux quelles on a attribué certaines de ces activités. Ce travail a eu pour objet la mise au point de procédés permettant d'obtenir les deux naphthodianthrones pures. Un critère de pureté des deux composés a d'abord été élaboré. Ensuite des protocoles d'extraction de la plante et de purification ont été mis au point jusqu'à l'obtention d'un extrait enrichi en hypéricine et pseudohypéricine. Les deux composés sont ensuite séparés par deux chromatographies successives sur silice et silice greffée et obtenus purs par précipitation. L'étude de leur comportement a montré que l'hypéricine est stable en milieu hydraté alors que la pseudohypéricine est transformée en isopseudohypéricine, nouvelle naphthodianthrone. Nous avons mis en évidence un équilibre entre la pseudo et isopseudohypéricine en milieu hydraté neutre et le déplacement total de l'équilibre vers l'isopseudohypéricine en milieu faiblement alcalin et vers la pseudohypéricine en milieu faiblement acide
St. -John's-wort (Hypericum perferatum) is a medical plant with multiple activities which contains two characteristic compounds, hypericin and the pseudohypericin, in wich one attributed some of these activities. This work had for object the settling of processes allowing to obtain the two naphthdianthrons at an high degree of purity. Firstly a criterion of purity of the two compound was elaborated. Subsequently, protocols for extracting the plant and purifying extracts were finalized for obtaining an extract enriched in hypericin and pseudohypericin. The compounds are then separated by two successive chromatographies using silica gel and silica gel C-18 reversed phase and obtained pure up to 95 % by precipitation. The study of their behavior showed that the hypericin is stable in hydrated medium while the pseudohypericin is transformed into isopseudohypericin, a new naphthodianthron. We shown an equilibrum between pseudo and isopseudohypericin in neutral hydrated medium and the a full deplacement of the equilibrum to isopseudohypericin in weakly alkaline medium and to pseudohypericin in weakly acid one
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9

Duran, Renan Ravetti. "Procédés d’extraction et de purification de molécules à haute valeur ajoutée issues de la biomasse bois." Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0325.

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Les sous-produits qui proviennent de l’industrie du bois, particulièrement les nœuds, contiennent différents types de molécules qui peuvent être valorisées comme source de composants bioactifs pouvant répondre à des besoins thérapeutiques. C’est sur cette idée que le projet "Le Bois Santé" a été conçu. Grâce à la collaboration de plusieurs partenaires, le présent travail vise dans un premier temps à développer des procédés d’extraction "verts" (solide-liquide et supercritique) pour obtenir un extrait riche en lignanes à partir d’un mélange de nœuds d’épicéa commun et de sapin pectiné. Les effets des conditions opératoires sur le rendement d’extraction de chaque composé cible et sur l’activité anti-oxydante des extraits ont été déterminés. Afin d’étudier le procédé complet, le projet vise à étudier l’impact des procédés de concentration et de séchage de l’extrait à partir de l’évaporation sous vide et de la lyophilisation. De plus, la séparation et la purification des composés ont été développées et optimisées par simulation grâce à la technique de chromatographie frontale
By-products from wood industry, particularly knots, contain different types of molecules that can be valued as a source of bioactive components meeting therapeutic needs. It is on this idea that the project "Le Bois Santé" was designed. Through the collaboration of several partnerships, the present work aims initially to develop a "green" extraction processes (solid-liquid and supercritical) to obtain an extract rich in lignans from a mixture of norway spruce and silver fir knots. The effects of operating conditions on the extraction yield of each target compound and the antioxidant activity of the extracts were determined. To understand the entire process, the project aims to investigate the impact of concentration and drying processes using vacuum evaporation and lyophilisation. Moreover, the separation and purification of the compounds have been developed and optimized using frontal chromatography technique
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10

Veillette, Marc. "Production de biodiesel à partir de microalgues par catalyses homogène et hétérogène." Thèse, Université de Sherbrooke, 2016. http://hdl.handle.net/11143/9752.

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Résumé : Au Canada, près de 80% des émissions totales, soit 692 Mt eq. CO[indice inférieur 2], des gaz à effet de serre (GES) sont produits par les émissions de dioxyde de carbone (CO[indice inférieur 2]) provenant de l’utilisation de matières fossiles non renouvelables. Après la Conférence des Nations Unies sur les changements climatiques, COP21 (Paris, France), plusieurs pays ont pour objectif de réduire leurs émissions de GES. Dans cette optique, les microalgues pourraient être utilisées pour capter le CO[indice inférieur 2] industriel et le transformer en biomasse composée principalement de lipides, de glucides et de protéines. De plus, la culture des microalgues n’utilise pas de terre arable contrairement à plusieurs plantes oléagineuses destinées à la production de biocarburants. Bien que les microalgues puissent être transformées en plusieurs biocarburants tels le bioéthanol (notamment par fermentation des glucides) ou le biométhane (par digestion anaérobie), la transformation des lipides en biodiesel pourrait permettre de réduire la consommation de diesel produit à partir de pétrole. Cependant, les coûts reliés à la production de biodiesel à partir de microalgues demeurent élevés pour une commercialisation à court terme en partie parce que les microalgues sont cultivées en phase aqueuse contrairement à plusieurs plantes oléagineuses, ce qui augmente le coût de récolte de la biomasse et de l’extraction des lipides. Malgré le fait que plusieurs techniques de récupération des lipides des microalgues n’utilisant pas de solvant organique sont mentionnées dans la littérature scientifique, la plupart des méthodes testées en laboratoire utilisent généralement des solvants organiques. Les lipides extraits peuvent être transestérifiés en biodiesel en présence d’un alcool tel que le méthanol et d’un catalyseur (catalyses homogène ou hétérogène). Pour la commercialisation du biodiesel à partir de microalgues, le respect des normes ASTM en vigueur est un point essentiel. Lors des essais en laboratoire, il a été démontré que l’extraction des lipides en phase aqueuse était possible afin d’obtenir un rendement maximal en lipides de 36% (m/m, base sèche) en utilisant un prétraitement consistant en une ébullition de la phase aqueuse contenant les microalgues et une extraction par des solvants organiques. Pour l’estérification, en utilisant une résine échangeuse de cations (Amberlyst-15), une conversion des acides gras libres de 84% a été obtenue à partir des lipides de la microalgue Chlorella protothecoïdes dans les conditions suivantes : température : 120°C, pression autogène, temps de réaction : 60 min, ratio méthanol/lipides: 0.57 mL/g et 2.5% (m/m) Amberlyst-15 par rapport aux lipides. En utilisant ces conditions avec une catalyse homogène (acide sulfurique) et une seconde étape alcaline avec de l’hydroxyde de potassium (température : 60°C ; temps de réaction : 22.2 min; ratio catalyseur microalgue : 2.48% (m/m); ratio méthanol par rapport aux lipides des microalgues : 31.4%), un rendement en esters méthyliques d’acides gras (EMAG) de 33% (g EMAG/g lipides) a été obtenu à partir des lipides de la microalgue Scenedesmus Obliquus. Les résultats démontrent que du biodiesel peut être produit à partir de microalgues. Cependant, basé sur les présents résultats, il sera necessaire de mener d’autre recherche pour prouver que les microalgues sont une matière première d’avenir pour la production de biodiesel.
Abstract : In Canada, near 80% of the greenhouse gases (GHG), 692 Mt eq. CO[subscript 2], are produced by CO[subscript 2] emissions from non renewable fossil fuel used. Following the United Nations conference on climate changes (COP21) (Paris, France), several countries have the objective to reduce their GHG emissions. Consequently, the microalgae should be used to trap industrial carbon dioxide and transform them to a biomass composed of lipids, carbon hydrates and proteins. Moreover, this type of culture does not require arable land in opposition to several oleagineous plant used to produce biofuels. Despite the fact that microalgae can be transformed to several biofuels as bioethanol (among others by fermentation) or biomethane (by anaerobic digestion), the lipid transformation into biodiesel shoud allow reducing the petrodiesel consumption. However, the cost linked to the biodiesel production from microalgae remain relatively high far for a short term commercialisation partially because microalgae are cultivated in aqueous phase in opposition to several oleagineous plants increase the biomass harvesting and the lipid extraction cost. Despite de fact that several techniques of microalgae lipids recovery which do not use organic solvents as mentioned in the literature, most methods tested in laboratory generally used organic solvents. The lipids extracted can be transformed into biodiesel in presence of an alcool such as methanol and a catalyst (homogeneous or heterogeneous). For the microalgae biodiesel commercialization, the respect of ASTM standards is an essential point. At the laboratory scale, it was shown that the lipid extraction in aqueous phase was possible to obtain a maximum yield of 36wt% (dry weight) by using a boiling pretreatment of the aqueous phase microalgae followed by an extraction with organic solvents. For the esterification of FFAs with a strong acid resin (Amberlyst-15), a FFAs conversion of 84% was obtained from Chlorella protothecoides microalgae lipids in the following conditions: temperature: 120°C, autogeneous pressure, reaction time: 60 min, methanol/lipids ratio: 0.57 mL/g and 2.5wt% Amberlyst-15 compared to lipids. With the same reaction conditions (1st step) with a homogeneous catalyst (H[subscript 2] SO[subscript 4]) and an alkaline second step with a catalyst of potassium hydroxide (KOH) (temperature: 60°C; reaction time: 22.2 min ; catalyst to microalgue ratio: 2.48wt%; methanol to lipids ratio: 31.4%), a fatty acid methyl ester (FAME) yield of 33% (g FAME/g lipids) was obtained from the Scenedesmus obliquus microalgae lipids. These results showed that biodiesel can be produced from microalgae lipids. However, based on these results, further research had be conducted in order to prove that microalgae are a promising raw matrial to produce biodiesel.
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Book chapters on the topic "Extraction et purification"

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"are purified lipid contents and others are not, and the puri-(Paspalum scrobiculatum), and barnyard (Echinocloa fied lipid content depends on the purification method. colona). Sridhar and Lakshminarayana [32] also reported Starch lipids (SL) are those bound to starch, and they FL contents of 5.0, 5.6, and 2.2% for Proso, Foxtail, and are the most difficult to extract. Since true SL are present Finger millet, respectively. Taira [45] found slightly high-inside the starch granules, even a very polar solvent such er average FL (ether extraction) contents for glutinous as WSB cannot extract them at ambient temperature. Effi-foxtail millet (4.2-5.1%, average 4.7% of 21 samples) cient extraction of SL requires mixtures of hot aqueous al-than for nonglutinous foxtail millet (4.0-4.7%, average cohol in proportions optimized for controlled swelling of 4.4% of 31 samples). Among millet, pearl millet contains the starch granules and solubilization of the lipids [25]. the most FL. The best solvents are n-propanol or isopropanol with water Lipid contents of rice in Table 2 were cited by Morrison (3:1, by volume) used under nitrogen at 100°C. However, [3] using the data of Nechaev and Sandler [2]. Taira and some n-butanol—water and methanol-water mixtures also Chang [46] reported that the average nonglutinous brown are reasonably efficient extraction solvents at 100°C [25]. rice FL (ether extraction) contents of 20 varieties each of Recently, a third lipid category was introduced. Starch sur-Indica and Japonica types were 2.7% (2.38-2.91%) and face lipids (SSL) are portions of the nonstarch lipids 2.9% (2.54-3.58%), respectively. More recently, Taira et (NSL), which become firmly absorbed onto or into starch al. [47] reported the average FL contents of 15 nongluti-granules during the separation of pure starch [24]. nous varieties as 2.5% (2.24-2.97%) for Indica, 2.5% Lipids are minor components of the cereal grains shown (2.12-2.94%) for Japonica, 2.7% (2.35-3.03%) for Sinica, in Table 2. Data in this table, expressed on a dry basis, and 2.6% (2.11-2.99%) for Japonica types. were calculated from reported values [3,16,26-41]. Also, some BL or TL contents were calculated by subtracting FL from TL or by adding FL to BL, depending on the avail-B. Nonstarch Lipid Classes of Grains ability of data. The FL contents range from 1.5 to 2% of Lipids can be separated into three broad classes by open-the kernel weights of barley, rice, rye, triticale, and wheat column silicic acid chromatography. Nonpolar lipids (NL) grains. They range from 3 to 7% of the kernel weights of are first eluted by chloroform, glycolipids (GL) are eluted oats, millet, corn, and sorghum. However, BL contents in next by acetone, and phospholipids (PL) are eluted last grains are more uniform than FL contents. Therefore, the with methanol. Mixtures of GL and PL are polar lipids FL:BL ratio is substantially higher for corn, millet, oats, (PoL). After NL elution from a silicic acid column, PoL and sorghum than for rye, triticale, and wheat grains. The can be eluted with methanol without the GL elution step. FL:BL ratios for barley and rice are intermediate. Lipids can also be separated into various classes by thin-High oil-containing grains such as corn are continuous-layer chromatography (TLC) using different development ly bred for higher oil content with improved production solvent systems. Each individual lipid class migrates dif-yield. Application of wide-line NMR spectroscopy for ferently on the thin-layer plate, and the difference in mi-nondestructive analysis of the oil content in single corn gration rates makes it possible to separate complex lipids kernels made selection for higher oil content more efficient into classes. The NL consists of SE, TG, DG, MG, and [42]. Corn hybrids with 6-8.5% oil content and grain FFA (see Table 1). The total NL content is obtained by yields equal to those of good commercial hybrids were adding these NL class contents as measured by densitome-produced [43]. try. Thus, the NL content of samples may differ, to some Several kinds of millet exist, and the lipid data in the extent, depending on methodology used (column separa-literature are confusing. Rooney compared the FL (ether tion or TLC separation). extraction) contents of several types of millet in a review The data [1,13,27,29,32,36-38,40,48-58] shown in paper [16]. The average FL contents of pearl millet (Pen-Table 3 may be used for only approximate comparison of nisetum typhoids) were 5.1% (4.1-5.6%, 14 samples), the NL content from different grains because some were 5.4% (2.8-8.0%, 167 samples, [44]), 5.6% (4.3-7.1%, 40 obtained by column chromatography and some by TLC. samples), and 6.2% (4.2-7.4%, 35 samples) [16]. Other All cereal grain lipids are richer in NL than in other class-reported average FL contents were 4.8% (4.6-5.0%, 6 es: 60-70% of the TL are NL in wheat (hexaploid), triti-samples) for foxtail millet (Setaria Italica), 5.8% cale, and rye; 65-80% for barley and oat groats; 77-87% (5.5-6.3%, 6 samples) for Japanese millet (Echinochloa for sorghum and rice; and 75-96% for corn and millet crusgalli), and 4.2% (3.8-4.9%, 20 samples) for proso (Pennisetum americanum). Sridhar and Lakshminarayana millet (Panicum miliaceum) [16]. Sridhar and Lakshmi-[32] reported 82, 80, and 79% of NL for Foxtail, Proso, narayana [30] reported a FL content range of 3.4-5.7% for and Finger millet, respectively. There are significant vari-small millet, including little (Panicum sumatrense), kodo etal effects on the NL/PoL ratio for corn and millet (P." In Handbook of Cereal Science and Technology, Revised and Expanded, 434. CRC Press, 2000. http://dx.doi.org/10.1201/9781420027228-43.

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Conference papers on the topic "Extraction et purification"

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Nottoli, Emmanuelle, Philippe Bienvenu, Didier Bourlès, Alexandre Labet, Maurice Arnold, and Maité Bertaux. "Determination of Long-Lived Radionuclide (10Be, 41Ca, 129I) Concentrations in Nuclear Waste by Accelerator Mass Spectrometry." In ASME 2013 15th International Conference on Environmental Remediation and Radioactive Waste Management. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/icem2013-96054.

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Radiological characterization of nuclear waste is essential for storage sites management. However, most of Long-Lived RadioNuclides (LLRN), important for long-term management, are difficult to measure since concentration levels are very low and waste matrices generally complex. In an industrial approach, LLRN concentrations are not directly measured in waste samples but assessed from scaling factors with respect to easily measured gamma emitters. Ideally, the key nuclide chosen (60Co, 137Cs) should be produced by a similar mechanism (fission or activation) as the LLRN of interest and should have similar physicochemical properties. However, the uncertainty on the scaling factors, determined from experimental and/or calculation data, can be quite important. Consequently, studies are performed to develop analytical procedures which would lead to determine precisely the concentration of LLRN in nuclear waste. In this context, the aim of this study was to determine the concentrations of three LLRN: 129I (T1/2 = 15.7×106 a), 41Ca (T1/2 = 9.94×104 a) and 10Be (T1/2 = 1.387×106 a) in spent resins used for primary fluid purification in Pressurized Water Reactors using Accelerator Mass Spectrometry (AMS) for measurement. The AMS technique combined mass spectrometry and nuclear physics to achieve highly efficient molecular and elemental isobars separation. Energies of several Million Electron-Volt transferred to the ions in the first accelerating part of specifically developed tandem accelerators lead to molecular isobars destruction through interaction with the argon gas used to strip the injected negative ions to positive ones. At the exit of the tandem accelerator, the energy acquired in both accelerating parts allows an elemental isobars separation based on their significantly different energy loss (dE) while passing through a thickness of matter dx that is proportional to their atomic number (Z) and inversely proportional to ions velocity (ν) according to the Bethe-Block law (1). (1)dEdx=k*Z2ν2 The use of a particle accelerator in conjunction with a selective ion source, mass and energy filters and a high-performance detector thus allow unambiguously identifying and measuring analyte concentration against much more abundant interfering isobars. The development of AMS and of related applications have recently been extensively reviewed [1–3]. Up to now, the potentialities of the accelerator mass spectrometry technique were explored for the measurement of cosmogenic radionuclides produced in the Earth’s environment either in the atmosphere or in the Earth’s crust (in situ-production). Many applications aiming to date and/or quantify Earth surface processes have been developed in the fields of geology, geomorphology and planetary sciences as well as archeology paleoanthropology and biomedicine. The present study extends the scope of AMS to nuclear industry. Because AMS facilities are not widely accessible and difficult to handle, LLRN concentrations in nuclear waste are usually determined using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and radiometric techniques. However for the measurement of very low LLRN concentrations, AMS becomes the most effective measurement method with detection limits of 105–106 atoms per sample. In this study, AMS measurements were performed using the French AMS national facility ASTER located at the Centre Européen de Recherche et d’Enseignement des Géosciences de l’Environnement (CEREGE). The challenge was to define a chemical treatment procedure allowing the measurement of the three nuclides, 10Be, 41Ca and 129I, by AMS. Each method selection was based on three main requirements: 1) a quantitative recovery in solution of Be, Ca, I and key radionuclides after resin mineralization, 2) a selective extraction from the sample matrix and the separation from β-γ emitters (3H, 14C, 55Fe, 59Ni, 60Co, 63Ni, 90Sr, 125Sb, 134Cs, 137Cs) and isobars, 3) the precipitation of each element under the best suited forms (i.e. AgI, CaF2, BeO) for AMS measurements. The chosen methods were optimized on synthetic solutions and finally applied for the determination of the three LLRN concentrations in spent resins from a 900 MWe Nuclear Power Reactor.
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