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5 results on '"analyse des composants"'

1. Component analysis of the X-C-Y anomeric effect (X = O, S; Y = F, OMe, NHMe) by DFT molecular orbital calculations and natural bond orbital analysis.

Author

Trapp, Melissa L., Watts, Jonathan K., Weinberg, Noham, and Pinto, B. Mario

Subjects
*MOLECULES, *HETEROCYCLIC compounds, *PHYSICAL & theoretical chemistry, *DIELECTRICS, *DIPOLE moments, *MAGNETIC dipoles, *POLARIZATION (Electricity)
Abstract

Six 2-Y-substituted oxacyclohexane and thiacyclohexane heterocycles (Y = F, OMe, NHMe) were examined using DFT molecular orbital calculations. Natural bond orbital (NBO) analysis of the total energy behaviour yielded the orbital-interaction factors contributing to the conformational equilibria. The dipole moments of the optimized systems were used to estimate the electrostatic contributions to the anomeric effect. The primary determinant of the X-C-Y anomeric effect was found to be the orbital interaction components associated with the combined endo- and exo-anomeric effects acting in concert in the axial conformers. Electrostatic interactions made a contribution to the observed conformer stabilization in all cases, but did not account for the relative magnitudes of the energy differences among conformers of homologous molecules. In the case of the methylamino substituent, accentuated steric interactions in the axial conformer precluded stabilization by the exo-anomeric interaction and consequently, the net endo/exo anomeric stabilization did not dominate the conformational equilibria. [ABSTRACT FROM AUTHOR]

Published
2006
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2. Source Identification and Apportionment of Trace Elements in Soils in the Yangtze River Delta, China

Author

Bin Jin, Zhou Shi, Zhiyi Fu, Ge Lou, Jiayu Wang, Yue Zhou, Yan Li, Bifeng Hu, Shuai Shao, Institute of Applied Remote Sensing and Information Technology, Zhejiang University, Unité de recherche Science du Sol (USS), Institut National de la Recherche Agronomique (INRA), Unité INFOSOL (ORLEANS INFOSOL), Sciences de la Terre et de l'Univers, Université d'Orléans (UO), Ningbo Agricultural Food Safety Management Station, Institute of Land Science and Property, School of Public Affairs, and InfoSol (InfoSol)

Subjects
Delta, Health, Toxicology and Mutagenesis, [SDV]Life Sciences [q-bio], lcsh:Medicine, trace elements, 010501 environmental sciences, 01 natural sciences, Sciences de la Terre, sciences du sol, Soil, biochemical analysis, Soil Pollutants, media_common, Cadmium, Principal Component Analysis, élément trace, trace element, modèle de distribution, 04 agricultural and veterinary sciences, 6. Clean water, Environmental chemistry, Environmental Monitoring, analyse des composants, Pollution, China, media_common.quotation_subject, finite mixture distribution model (FMDM), chemistry.chemical_element, Weathering, source identification and apportionment, Article, Rivers, Metals, Heavy, principal component analysis (PCA), 0105 earth and related environmental sciences, Yangtze River Delta, chine, Pollutant, Topsoil, Spatial Analysis, Models, Statistical, Environmental and Society, lcsh:R, Public Health, Environmental and Occupational Health, analyse biochimique, 15. Life on land, Mercury (element), soil sciences, chemistry, 13. Climate action, Soil water, Earth Sciences, 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, Environmental science, Environnement et Société, Environmental Pollution
Abstract

Trace elements pollution has attracted a lot of attention worldwide. However, it is difficult to identify and apportion the sources of multiple element pollutants over large areas because of the considerable spatial complexity and variability in the distribution of trace elements in soil. In this study, we collected total of 2051 topsoil (0&ndash, 20 cm) samples, and analyzed the general pollution status of soils from the Yangtze River Delta, Southeast China. We applied principal component analysis (PCA), a finite mixture distribution model (FMDM), and geostatistical tools to identify and quantitatively apportion the sources of seven kinds of trace elements (chromium (Cr), cadmium (Cd), mercury (Hg), copper (Cu), zinc (Zn), nickel (Ni), and arsenic (As)) in soil. The PCA results indicated that the trace elements in soil in the study area were mainly from natural, multi-pollutant and industrial sources. The FMDM also fitted three sub log-normal distributions. The results from the two models were quite similar: Cr, As, and Ni were mainly from natural sources caused by parent material weathering, Cd, Cu, and Zu were mainly from mixed sources, with a considerable portion from anthropogenic activities such as traffic pollutants, domestic garbage, and agricultural inputs, and Hg was mainly from industrial wastes and pollutants.

Published
2018
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3. Variability of traits and bioactive compounds in the fruit and pulp of six mamey apple (Mammea americana L.) accessions

Author

Katia Rochefort, Sandra Adenet, Louis Fahrasmane, Armelle Péroumal, Guylène Aurore, Qualité des fruits et légumes tropicaux (UMR Qualitrop), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université des Antilles et de la Guyane (UAG), Pôle Agroalimentaire Régional de la Martinique (PARM), Unité de Recherches Zootechniques (URZ), Institut National de la Recherche Agronomique (INRA), Connaissance et Valorisation : Chimie des Matériaux, Environnement, Energie (COVACHIM- M2E), Université des Antilles (UA), and La Région Martinique

Subjects
0106 biological sciences, [SDV]Life Sciences [q-bio], Flavonoid, abricot, Mammea americana, Mamey, Physical analysis, Physico-chemical analyses, Biochemical analyses, Total phenolics content, Total flavonoids, Principal component analysis, Cluster analysis, Variability, bioactive compound, 01 natural sciences, Analytical Chemistry, analyse physicochimique, chemistry.chemical_compound, biochemical analysis, analyse physique, Carotenoid, chemistry.chemical_classification, biology, Pulp (paper), food and beverages, 04 agricultural and veterinary sciences, General Medicine, 040401 food science, Bioactive compound, Horticulture, physical analysis, analyse des composants, engineering.material, 0404 agricultural biotechnology, Phenols, stomatognathic system, Botany, Nectar, flavonoid, pulpe de fruit, physicochemical analysis, Flavonoids, mammea americana, JAMS, analyse biochimique, fruit, biology.organism_classification, Carotenoids, stomatognathic diseases, chemistry, engineering, flavonoïde, Mammea, 010606 plant biology & botany, Food Science, variabilité phénologique
Abstract

Our objective was to compare fruit morphology, physico-chemistry and bioactive compounds content of the edible pulp of six Mammea americana accessions. The results showed that this fruit was rather big, weighing on average 600 to 1100 g depending on the accession, and spherical to oblate-shaped. The pulp represented between 50 and 70% of the weight of the whole fruit. The pulp adhered only partially to the seeds in 5 of the 6 accessions studied, while the last one exhibited full adherence. The fresh pulp was acidic, sweet, succulent and crunchy. The fruits studied had a variety of qualities, providing various opportunities for post-harvest uses: fruit salads, nectar preparation, jams and jellies, or export. We have established for the first time the total phenolic compounds and total flavonoids contents in the pulp of mamey apple fruits. The pulp colour was highly correlated with total phenolic compounds and total carotenoids contents.

Published
2017
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4. Typology of the Noir de Bigorre pig farming systems

Author

Faure, Justine, Fonseca, Alexandre, Garcia-Launay, Florence, Physiologie, Environnement et Génétique pour l'Animal et les Systèmes d'Elevage [Rennes] (PEGASE), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, Consortium du Noir de Bigorre, European Project: 634476,H2020,H2020-SFS-2014-2,TREASURE(2015), AGROCAMPUS OUEST, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut National de la Recherche Agronomique (INRA), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)

Subjects
race porcine locale, [SDV.GEN]Life Sciences [q-bio]/Genetics, Outdoor, [SDV]Life Sciences [q-bio], durabilité des systèmes d'élevage, Gascon breed, Hierarchical clustering, socio-economic dynamics, système d'élevage, élevage plein air, classification hierarchique, porc gascon, [SDV.GEN.GA]Life Sciences [q-bio]/Genetics/Animal genetics, analyse socio-économique, [INFO]Computer Science [cs], typologie, ComputingMilieux_MISCELLANEOUS, analyse des composants
Abstract

International audience

Published
2016

5. Microwave, ultrasound, thermal treatments, and bead milling as intensification techniques for extraction of lipids from oleaginous Yarrowia lipolytica yeast for a biojetfuel application

Author

Alice Meullemiestre, Farid Chemat, Cassandra Breil, Maryline Abert-Vian, Sécurité et Qualité des Produits d'Origine Végétale (SQPOV), Avignon Université (AU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), French Government Investissement d'Avenir ANR PROBIO3, and Abert-Vian, Maryline

Subjects
0106 biological sciences, [SDV]Life Sciences [q-bio], Yarrowia, 02 engineering and technology, Oleaginous microorganisms, 01 natural sciences, chemistry.chemical_compound, [SDV.IDA]Life Sciences [q-bio]/Food engineering, 0202 electrical engineering, electronic engineering, information engineering, Ultrasonics, Microwaves, Waste Management and Disposal, consommation d'énergie, méthode d'extraction, microscopie à balayage électronique, Chloroform, acide gras, biology, Lipid extraction, Microwave, Ultrasound, Bead milling, General Medicine, optimisation des procédés, Lipids, Solvent, extraction par ultrasons, lipids (amino acids, peptides, and proteins), prétraitement, analyse des composants, Environmental Engineering, 020209 energy, Bioengineering, 010608 biotechnology, Maceration (wine), [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Chromatography, Renewable Energy, Sustainability and the Environment, Extraction (chemistry), comparaison de méthodes, biology.organism_classification, Yeast, évaluation de l'impact environnemental, chemistry, Biofuels, Yield (chemistry), Methanol, yarrowia lipolytica, traitement aux microondes
Abstract

International audience; In the present work, two different ways of lipids extraction from Yarrowia lipolytica yeast were investigated in order to maximize the extraction yield. Firstly, various modern techniques of extraction including ultrasound, microwave, and bead milling were tested to intensify the efficiency of lipid recovery. Secondly, several pretreatments such as freezing/defrosting, cold drying, bead milling, and microwave prior two washing of mixture solvent of chloroform:methanol (1:2, v/v) were study to evaluate the impact on lipid recovery. All these treatments were compared to conventional maceration, in terms of lipids extraction yield and lipid composition analysis. The main result of this study is the large difference of lipid recovery among treatments and the alteration of lipids profile after microwave and ultrasound techniques.

Published
2016
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