Search results for "nitrate"

La communauté nitrate-réductrice : modèle d'évaluation de l'impact du type de fertilisant et du mode de travail du sol à Madagascar

2007

Activity, size and structure of the nitrate reducer community in relation to land-use and fertilization regime in Madagascar

2007

Communication orale, résumé; absent

Pd-Cu catalysts supported on anion exchange resin for the simultaneous catalytic reduction of nitrate ions and reductive dehalogenation of organochlo…

2019

International audience; The present work proposes the simultaneous removal of these classes of pollutants by a catalytic hydrotreatment processes. For this purpose, bimetallic Pd-Cu catalysts (with mass ratio Pd:Cu of 4:1) supported on macroporous strong base anion resin were prepared by different methods. The catalysts were characterized (by XRD, SEMEDX, XPS, AAS and H-2 chemisorption) and tested in a continuous flow system. The selected catalyst preparation protocol consists in a two-step method, which implies the deposition of palladium by ion exchange and the subsequent deposition of copper by controlled reaction on the surface of the pre-reduced palladium. The effectiveness of the cata…

Spatial distribution of ammonia-oxidizing bacteria and archaea across a 44-hectare farm related to ecosystem functioning

2011

Characterization of spatial patterns of functional microbial communities could facilitate the understanding of the relationships between the ecology of microbial communities, the biogeochemical processes they perform and the corresponding ecosystem functions. Because of the important role the ammonia-oxidizing bacteria (AOB) and archaea (AOA) have in nitrogen cycling and nitrate leaching, we explored the spatial distribution of their activity, abundance and community composition across a 44-ha large farm divided into an organic and an integrated farming system. The spatial patterns were mapped by geostatistical modeling and correlations to soil properties and ecosystem functioning in terms …

CCDC 1559171: Experimental Crystal Structure Determination

2017

Related Article: Eloisa O. Ribeiro, Nathália R. de Campos, Antônio C. Doriguetto, Wdeson P. Barros, Marcos A. Ribeiro, Elgte E. B. De Paula, Humberto O. Stumpf, Francesc Lloret, Miguel Julve, Maria V. Marinho|2017|CrystEngComm|19|5460|doi:10.1039/C7CE01230F

Biostimulant Potential of Humic Acids Extracted From an Amendment Obtained via Combination of Olive Mill Wastewaters (OMW) and a Pre-treated Organic …

2018

Olive mill wastewaters (OMW) detain contain significant levels of phenolic compounds with antimicrobial/phytotoxic activity and high amounts of undecomposed organic matter that may a high pollutant load that exerts negative effects on soil biology because of significant levels in phenolic compounds with antimicrobial/phytotoxic activity and limited biodegradability, and high amounts of undecomposed organic matter. Among OMW detoxification techniques, those focusing on oxidative degradation of phenolic compounds are relevant those focusing on oxidative degradation of phenolic compounds to reduce their toxicity. The composting (bio-oxidation) process in particular, exploits exothermic oxidati…

Principes de fonctionnement de la symbiose fixatrice de l’azote : impacts agronomiques et environnementaux.

2017

National audience; Par leur capacité à s’associer avec des bactéries du sol fixant l’azote atmosphérique, les légumineuses ont la particularité de pouvoir être cultivées sans utiliser d’engrais azotés, et d’être une source d’azote pour d’autres cultures. Elles ont ainsi un rôle particulier dans la gestion des flux d’azote au sein des systèmes de culture, et dans les bilans environnementaux qui en découlent. Dans ce texte, nous décrivons le processus de fixation symbiotique de N2 au cours de la culture, en considérant sa réponse à la disponibilité en nitrate, et aux autres facteurs environnementaux et facteurs génétiques. Puis, nous explicitons la façon dont la minéralisation des résidus de …

Characterization of the Antioxidant Properties of Pentaerithrityl Tetranitrate (PETN)-Induction of the Intrinsic Antioxidative System Heme Oxygenase-…

2009

Organic nitrates are among the oldest and yet most commonly employed drugs in the chronic therapy of coronary artery disease and congestive heart failure. While they have long been used in clinical practise, our understanding of their mechanism of action and of their side effects remains incomplete. To date, the most commonly employed nitrates are isosorbide mononitrate (ISMN), isosorbide dinitrate (ISDN), and nitroglycerin (GTN). Another nitrate, pentaerithrityl tetranitrate (PETN), has long been employed in eastern European countries and is currently being reintroduced also in western countries. So far, PETN is the only organic nitrate in clinical use, which is devoid of induction of oxid…

Modeling for the active site nitrate reductase. Oxidation of the complex [MovO(O2CC(S) CH3Ph)2]− by nitrate and nitrite in methanol

1998

Abstract Under acid conditions the [MoVIO2(O2CC(S)CH1Ph)2]2 reacts with thiols to yield the monomeric [MoVO(O2CC(S)CH3Ph)2] and disulfide. The reduced complex [MoVO(O2CC(S)CH3Ph)2]− can react with NO3− and NO2− in a one-electron step yeilding respectively NO2 and NO and the original molybdenum (VI)-dioxo complex. The experimental pseudo-first-order rate constant with respect to the Mo(V) complex at 25°C was found to be kobs=2.3×10−4s−1 for NO3− and kobs=1.0×10−2 for NO2−. Oxo transfers to and from the substrate have been coupled to produce a catalytic system which turns over the reaction RSH+(No3− or NO2−)+H+a 1 2 [ RS ] 2 +( NO ] 2 or NO )+ H 2 O , in which thiols, NO1− and NO2− serve as a…

Die Wirkung unterschiedlicher Lichtintensitäten auf die Nitratreduktase-Aktivität, den Gehalt an löslichen Proteinen und löslichen reduzierenden Zuck…

1977

Summary Plants of Sinapis alba (white mustard) grown under strong light conditions have a higher content of soluble reducing sugars, of soluble proteins and a higher dry wight during growth from germination to flowering. Furthermore, in these plants the nitrate reductase activity is essentially higher during the vegetative development, but before the beginning of the flowering phase the activity is less than the level of plants grown under low light intensities. The results obtained indicate a direct correlation between nitrate reductase activity and the content of soluble proteins. In the high-light plants both components show distinct maxima 13—14 days after sowing the seeds. The enhancem…