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Sample records for amines utilisees pour

  1. Study of the degradation mechanisms of amines used for the capture of CO{sub 2} in industrial fumes; Etude des mecanismes de degradation des amines utilisees pour le captage du CO{sub 2} dans les fumees

    Energy Technology Data Exchange (ETDEWEB)

    Lepaumier, H

    2008-10-15

    Global warming leads to reduce greenhouse gas emissions. Post combustion CO{sub 2} capture with solvent is the most advanced technology to reduce CO{sub 2} emissions in industrial fumes. A major problem associated with chemical absorption of CO{sub 2} using the benchmark ethanolamine (MEA) is solvent degradation through irreversible side reactions with CO{sub 2} and O{sub 2} which leads to numerous harmful impacts to the process: corrosion, solvent loss, foaming, fouling, and viscosity increase. So, developing new amines with higher chemical stability is essential. This work is based on the chemical stability study of 17 different molecules. Their structures have been chosen in order to establish structure-property relationships: alkanolamines, known for gas treatment application (MEA, DEA, MDEA, AMP...), di-amines, and tri-amines without alcohol function. Impact of temperature, CO{sub 2}, and O{sub 2} on degradation has been studied. Strong experimental conditions have been used to observe significant degradation after a 15 days experiment. Separation, identification and quantification of degradation products have been performed by using different testing instructions such as gas chromatography, mass spectrometry, ionic chromatography and NMR. Different mechanisms are proposed to explain most of degradation compounds. Radical reactions (dealkylation, alkylation, ring-closure reactions and piperazinones formation) are involved under O{sub 2} pressure whereas CO{sub 2} induces ionic reactions (dealkylation, alkylation, addition, ring-closure reactions and oxazolidinones or imidazolidinones formation). Large discrepancies of stability are noticed among the different amines. Knowledge of degradation products and reaction mechanisms has thus permitted to establish some relationships between structure and chemical stability: for example, role of the amine function (primary, secondary, tertiary), impact of alkyl chain length between the two amino groups and steric

  2. Analytical methods used by the geochemical section: water; Methodes d'analyses utilisees par la section de geochimie: les eaux

    Energy Technology Data Exchange (ETDEWEB)

    Berthollet, P.; Cavalier, G. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1971-07-01

    The authors describe the analytical methods used by the C.E.A. Geochemical Section to determine the chemical composition of natural waters encountered during the prospecting of uraniferous deposits or in the course of mining operations. Because of the diversity of the samples and the different items of information requested, methods were selected and adapted to answer to the demands peculiar to mining research. Methods and know-how concerning the quantitative analysis of natural water to find out the concentration of the following chemicals are reviewed: carbonates and bicarbonates, calcium, magnesium, chlorides, sodium and potassium, sulfates, nitrates, silica, phosphates, iron, manganese, aluminium, fluorides, dissolved oxygen, CO{sub 2}, SH{sub 2} and sulphur, and uranium. (authors) [French] Les auteurs decrivent les methodes d'analyses utilisees par la Section de Geochimie du C.E.A., pour la determination de la composition chimique des eaux naturelles rencontrees au cours de prospections de gites uraniferes ou de travaux miniers. La diversite des echantillons et les differents renseignements demandes a l'analyse les ont conduit a selectionner et a adapter des methodes afin qu'elles repondent aux exigences particulieres de la recherche miniere. Les methodes concernant le dosage dans les eaux superficielles et eaux souterraines des elements qui suivent sont presentees : carbonates and bicarbonates, calcium, magnesium, chlorures, sodium et potassium, sulfates, nitrates, silice, phosphates, fer ferreus et ferrique, manganese, aluminium, fluorures, oxygene dissous, CO{sub 2} libre, SH{sub 2} et soufre total, et uranium. (auteurs)

  3. Amine : une plate-forme pour le développement de systèmes et d’agents intelligents

    Directory of Open Access Journals (Sweden)

    Karim Bouzoubaa

    2005-10-01

    Full Text Available This paper presents an overview of Amine ; a multi-layer and open-source platform, implemented in Java and dedicated to the development of intelligent systems and agents. Amine is composed of four layers : a a kernel layer that enables the creation, edition, update and manipulation of multi-lingua ontologies, b an algebraic layer that offers a set of elementary data types, structured types and various matching-based operations, c a programming layer that provides three programming paradigms: i an ontology or memory-based programming paradigm which is concerned by incremental and automatic integration of knowledge in an ontology (or agent memory, ii a pattern-matching and rule-based programming paradigm, embedded in PROLOG+CG language, and iii an activation and propagation-based programming paradigm, embedded in SYNERGY language, and d an agent and multi-agent systems layer that enables the development of agent-based applications.

  4. Graph Machine Based-QSAR Approach for Modeling Thermodynamic Properties of Amines: Application to CO2 Capture in Postcombustion Approche QSAR Graph Machines pour la modélisation des propriétés thermodynamiques des amines : application au captage du CO2 en postcombustion

    Directory of Open Access Journals (Sweden)

    Porcheron F.

    2013-03-01

    Full Text Available Amine scrubbing is usually considered as the most efficient technology for CO2 mitigation through postcombustion Carbon Capture and Storage (CCS. However, optimization of the amine structure to improve the solvent properties requires to sample a large number of possible candidates and hence to gather a large amount of experimental data. In this context, the use of QSAR (Quantitative Structure Activity Relationship statistical modeling is a powerful tool as it performs a mapping of a set of input vectors (i.e. the characteristics or the properties of the molecules under consideration to a set of output vectors (i.e. their targeted properties. In this work, we used a high throughput screening experimental device to measure CO2 solubility data on a set of 46 amine aqueous solutions. Absorption isotherms are represented using a thermodynamic model based on two thermodynamic constants, pKa*  and pKc* , accounting for the main chemical reactions occurring in the liquid phase between amine and CO2. Then, we used a statistical approach named Graph Machines at the same time to cluster the molecules and to model the variation of the acidity constant pKa*  as a function of the molecular structure. The originality of our approach is the use of graphs to represent molecules in multidimensional spaces and simultaneously construct predictive models of their physicochemical properties based on these graphs. This approach is applied in this paper to predict the thermodynamic properties of a set of 5 new molecules. Le procédé d’absorption aux amines est considéré comme la technologie la plus efficace pour limiter les rejets de CO2 dans le cadre du captage en postcombustion puis du stockage du CO2. Cependant, l’optimisation des propriétés du solvant nécessite d’évaluer un grand nombre de candidats potentiels et donc de collecter une quantité importante de propriétés expérimentales. Dans ce contexte, l’utilisation de méthodes de mod

  5. Analyse experimentale des performances d'une batterie au lithium pour l'aeronautique

    Science.gov (United States)

    Bonnin, Romain

    Ce memoire a pour objectif d'identifier et d'etudier les performances necessaires pour qu'une batterie au lithium puisse etre utilisee dans le secteur de l'aeronautique. C'est pourquoi dans le cadre de notre recherche, nous allons proposer une procedure de tests permettant d'analyser et de determiner si la batterie au lithium peut etre implantee dans un avion. En vue de repondre a l'analyse des performances, une etude des fonctionnalites demandees par l'avion ainsi que des normes preexistantes vont etre effectuees. Suite a cette etape, nous allons elaborer un banc d'essais. Une fois le banc d'essais acheve, nous allons tester une batterie au lithium qui est supposee disposer de toutes les caracteristiques techniques requises pour etre implantee dans un avion. Ces tests nous permettront donc d'emettre un avis sur l'utilisation des batteries au lithium dans le domaine de l'aeronautique.

  6. Extraction of some acids using aliphatic amines; Extraction de quelques acides par des amines aliphatiques

    Energy Technology Data Exchange (ETDEWEB)

    Matutano, L. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-06-01

    Hydrochloric, nitric, sulphuric, perchloric, phosphoric, acetic and formic acids in aqueous solution (0.05 to 10 M) are extracted by amberlite LA2 and trilaurylamine in solution, 5 per cent by volume, in kerosene and xylene respectively. The extraction process consists of: neutralization of the amine salt; a 'molecular extraction', i.e. an extraction using an excess of acid with respect to the stoichiometry of the amine salt. According to the behaviour of the acid during the extraction, three groups may be distinguished: completely dissociated acids, carboxylic acids, phosphoric acid. This classification is also valid for the extraction of the water which occurs simultaneously with that of the acid. An extraction mechanism is put forward for formic acid and the formation constant of its amine salt is calculated. (author) [French] Les acides chlorhydrique, nitrique, sulfurique, perchlorique, phosphorique, acetique et formique, en solution aqueuse - 0,05 a 10 M - sont extraits par l'amberlite LA2 et la trilaurylamine en solution, a 5 pour cent en volume, dans le kerosene et le xylene respectivement. L'extraction comprend: une neutralisation de l'amine par l'acide avec formation d'un sel d'amine; une 'extraction moleculaire', c'est-a-dire une extraction d'acide en exces par rapport a la stoechiometrie du sel d'amine. Suivant le comportement des acides au cours de l'extraction nous distinguons trois groupes: acides entierement dissocies, acides carboxyliques, acide phosphorique. Cette classification est egalement valable pour l'extraction de l'eau qui est simultanee a celle de l'acide. Un mecanisme d'extraction pour l'acide formique est propose et nous calculons la constante de formation de son sel d'amine. (auteur)

  7. Methodologies nouvelles pour la realisation d'essais dans la soufflerie Price-Paidoussis

    Science.gov (United States)

    Flores Salinas, Manuel

    Le present memoire en genie de la production automatisee vise a decrire le travail effectue dans la soufflerie Price-Paidoussis du laboratoire LARCASE pour trouver les methodologies experimentales et les procedures de tests, qui seront utilisees avec les modeles d'ailes actuellement au laboratoire. Les methodologies et procedures presentees ici vont permettre de preparer les tests en soufflerie du projet MDO-505 Architectures et technologies deformables pour l'amelioration des performances des ailes, qui se derouleront durant l'annee 2015. D'abord, un bref historique des souffleries subsoniques sera fait. Les differentes sections de la soufflerie Price-Paidoussis seront decrites en mettant l'emphase sur leur influence dans la qualite de l'ecoulement qui se retrouve dans la chambre d'essai. Ensuite, une introduction a la pression, a sa mesure lors de tests en soufflerie et les instruments utilises pour les tests en soufflerie au laboratoire LARCASE sera presente, en particulier le capteur piezoelectrique XCQ-062. Une attention particuliere sera portee au mode de fonctionnement, a son installation, a la mesure et a la detection des frequences et aux sources d'erreurs lorsqu'on utilise des capteurs de haute precision comme la serie XCQ-062 du fournisseur Kulite. Finalement, les procedures et les methodologies elaborees pour les tests dans la soufflerie Price-Paidoussis seront utilisees sur quatre types d'ailes differentes. L'article New methodology for wind tunnel calibration using neural networks - EGD approch portant sur une nouvelle facon de predire les caracteristiques de l'ecoulement a l'interieur de la soufflerie Price-Paidoussis se trouve dans l'annexe 2 de ce document. Cet article porte sur la creation d'un reseau de neurones multicouche et sur l'entrainement des neurones, Ensuite, une comparaison des resultats du reseau de neurones a ete fait avec des valeurs simules avec le logiciel Fluent.

  8. Nouvelle economie: utilisation de l'architecture de la comptabilite nationale pour estimer l'importance de l'economie de haute technologie

    OpenAIRE

    Beckstead, Desmond; Burrows, Sean; Gellatly, Guy

    2007-01-01

    Le present document montre comment l'architecture statistique du Systeme de comptabilite nationale du Canada peut etre utilisee pour etudier l'importance et la composition d'un secteur economique particulier. A titre d'illustration, l'analyse est axee sur le secteur des technologies de l'information et des communications (TIC) et, par consequent, sur l'ensemble des industries productrices de technologies et des produits de technologie qui sont les plus couramment lies a ce que l'on appelle so...

  9. Amine Functionalized Porous Network

    KAUST Repository

    Eddaoudi, Mohamed

    2015-05-28

    Amine groups can be introduced in porous materials by a direct (one pot) or post-synthetic modification (PSM) process on aldehyde groups, and the resulting porous materials have increased gas affinity.

  10. Fluorinated Amine Stereotriads via Allene Amination.

    Science.gov (United States)

    Liu, Lu; Gerstner, Nels C; Oxtoby, Lucas J; Guzei, Ilia A; Schomaker, Jennifer M

    2017-06-16

    The incorporation of fluorine into organic scaffolds often improves the bioactivity of pharmaceutically relevant compounds. C-F/C-N/C-O stereotriad motifs are prevalent in antivirals, neuraminidase inhibitors, and modulators of androgen receptors, but are challenging to install. An oxidative allene amination strategy using Selectfluor rapidly delivers triply functionalized triads of the form C-F/C-N/C-O, exhibiting good scope and diastereoselectivity for all syn products. The resulting stereotriads are readily transformed into fluorinated pyrrolidines and protected α-, β-, and γ-amino acids.

  11. Characterization of particulate amines

    International Nuclear Information System (INIS)

    Gundel, L.A.; Chang, S.G.; Clemenson, M.S.; Markowitz, S.S.; Novakov, T.

    1979-01-01

    The reduced nitrogen compounds associated with ambient particulate matter are chemically characterized by means of ESCA and proton activation analysis. Ambient particulate samples collected on silver filters in Berkeley, California were washed with water and organic solvents, and ESCA and proton activation analysis were performed in order to determine the composition of various nitrogen compounds and the total nitrogen content. It is found that 85% of the amines originally present in ambient particulate matter can be removed by water extraction, whereas the ammonium and nitrate are completely removed. An observed increase in ammonium ion in the extract, compared with its concentration in the original sample, coupled with the commensurate decrease in amine concentration, is attributed to the hydrolysis of amide groups, which may cause analytical methods based on extraction to yield erroneous results

  12. The economics of amine usage

    International Nuclear Information System (INIS)

    Fountain, M.J.

    1994-01-01

    The EPRI computer programm, 'Aminemod', a PWR chemistry model, has been used to compare the technical advantages of the 'advanced' amines, ethanolamine, 1,2 diaminoethane and 5 aminopentanol over morpholine in generating an elevated pH in the moisture separator and the economics of using these amines has been assessed by using an MS Excel spreadsheet in conjunction with Aminemod. The advanced amines are capable of achieving 1 pH unit above neutrality, the EPRI target for prevention of erosion-corrison, at acceptable cost and, compared with 'conventional' amines, at considerably reduced ionic load on the condensate polisher. The exercise demonstrates that it is essential to evaluate the effect of an amine dosing regime on the total operating cost and that it is not possible to prejudge the economic outcome on the basis of an amine's purchase price. (orig.)

  13. Exposure to heterocyclic amines.

    Science.gov (United States)

    Wakabayashi, K; Ushiyama, H; Takahashi, M; Nukaya, H; Kim, S B; Hirose, M; Ochiai, M; Sugimura, T; Nagao, M

    1993-03-01

    Many mutagenic heterocyclic amines (HAs) have been isolated from cooked foods and pyrolysates of amino acids and proteins, and the carcinogenicity of 10 of these HAs in rodents and of 1 in monkeys has been reported. Quantification of these carcinogenic HAs in various kinds of cooked foods indicated that the level of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) was highest (0.56-69.2 ng/g), that of 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) was second highest (0.64-6.44 ng/g), and those of other HAs were 0.03-2.50 ng/g. Heterocyclic amines were found in urine samples of 10 healthy volunteers consuming a normal diet, but HAs were not detectable in urine samples of three patients receiving parenteral alimentation. These results strongly suggest that humans are continuously exposed to HAs derived from food in the normal diet. Based on quantitative data on the levels of HAs in cooked foods and urine samples, the daily exposures to PhIP and MeIQx were estimated to be 0.1-13.8 micrograms and 0.2-2.6 micrograms per person, respectively. These levels of carcinogenic HAs are in the same range as those of other carcinogens such as N-nitrosodimethylamine and benzo[a]pyrene to which humans are exposed.

  14. Standard CGIF interoperability in Amine

    OpenAIRE

    Kabbaj, A.; Launders, I.; Polovina, S.

    2009-01-01

    The adoption of standard CGIF by CG tools will enable interoperability between them to be achieved, and in turn lead to the interoperability between CG tools and other tools. The integration of ISO Common Logic’s standard CGIF notation in the Amine platform is presented. It also describes the first steps towards full interoperability between the Amine CG tool (through its Synergy component) and CharGer, a representative CG tool that supports similar interoperability and for process (or ‘activ...

  15. ARC Code TI: Pour

    Data.gov (United States)

    National Aeronautics and Space Administration — Pour is a general-purpose information service framework designed to accommodate a wide variety of information types with support for high volume, low frequency...

  16. Amine Swingbed Payload Project Management

    Science.gov (United States)

    Walsch, Mary; Curley, Su

    2013-01-01

    The International Space Station (ISS) has been designed as a laboratory for demonstrating technologies in a microgravity environment, benefitting exploration programs by reducing the overall risk of implementing such technologies in new spacecraft. At the beginning of fiscal year 2010, the ISS program manager requested that the amine-based, pressure-swing carbon dioxide and humidity absorption technology (designed by Hamilton Sundstrand, baselined for the Orion Multi-Purpose Crew Vehicle, and tested at the Johnson Space Center in relevant environments, including with humans, since 2005) be developed into a payload for ISS Utilization. In addition to evaluating the amine technology in a flight environment before the first launch of the Orion vehicle, the ISS program wanted to determine the capability of the amine technology to remove carbon dioxide from the ISS cabin environment at the metabolic rate of the full 6 ]person crew. Because the amine technology vents the absorbed carbon dioxide and water vapor to space vacuum (open loop), additional hardware needed to be developed to minimize the amount of air and water resources lost overboard. Additionally, the payload system would be launched on two separate Space Shuttle flights, with the heart of the payload-the swingbed unit itself-launching a full year before the remainder of the payload. This paper discusses the project management and challenges of developing the amine swingbed payload in order to accomplish the technology objectives of both the open -loop Orion application as well as the closed-loop ISS application.

  17. Conditioning of primates for experiments; Conditionnement des primates pour l'experimentation

    Energy Technology Data Exchange (ETDEWEB)

    Legeay, G.; Geneste, M.; Brawers, G. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1965-07-01

    The preparation of the monkey for experiments is one branch of zootechny applied to laboratory animals. The construction of a monkey-house at the Saclay Nuclear Research Centre has made it possible to study the hygiene rules necessary for obtaining subjects with relatively stable biological parameters. This hygiene includes: - prophylactic treatment, because the animals received lived originally in the wild state, - a balanced diet according to modern dietetic standards, - a habitat hygiene which recreates the original living conditions of the species. The possibility of reproduction has been used as a criterion of the efficiency of the methods applied. (authors) [French] La mise en condition du singe en vue de son utilisation a des fins experimentales est une branche de la zootechnie appliquee aux animaux de laboratoire. La realisation d'une singerie au CEN/SACLAY a permis d'etudier les regles d'hygiene requise pour obtenir des sujets dont les parametres biologiques soient relativement stables. L'hygiene comporte: - des soins prophylactiques car les animaux livres proviennent de capture a l'etat sauvage, - une alimentation equilibree, selon les normes modernes de la dietetique, - une hygiene de l'habitat recreant les conditions du milieu originel de l'espece. La possibilite de la reproduction a ete utilisee comme critere de l'efficacite des methodes mises en oeuvre.

  18. potential bag filter for volatile organic amines

    Indian Academy of Sciences (India)

    VADDYPALLY SHIVAIAH

    2018-03-22

    Mar 22, 2018 ... be described as a potential bag filter for volatile organic amines. Keywords. Volatile organic amines; hydrogen ..... this bag filter, which can capture volatile amines to form. Figure 8. Thermal ellipsoid plot of ..... huber H, Baumann M and Amann A 2013 Blood and breath levels of selected volatile organic ...

  19. Conception et optimisation d'une peau en composite pour une aile adaptative =

    Science.gov (United States)

    Michaud, Francois

    Les preoccupations economiques et environnementales constituent des enjeux majeurs pour le developpement de nouvelles technologies en aeronautique. C'est dans cette optique qu'est ne le projet MDO-505 intitule Morphing Architectures and Related Technologies for Wing Efficiency Improvement. L'objectif de ce projet vise a concevoir une aile adaptative active servant a ameliorer sa laminarite et ainsi reduire la consommation de carburant et les emissions de l'avion. Les travaux de recherche realises ont permis de concevoir et optimiser une peau en composite adaptative permettant d'assurer l'amelioration de la laminarite tout en conservant son integrite structurale. D'abord, une methode d'optimisation en trois etapes fut developpee avec pour objectif de minimiser la masse de la peau en composite en assurant qu'elle s'adapte par un controle actif de la surface deformable aux profils aerodynamiques desires. Le processus d'optimisation incluait egalement des contraintes de resistance, de stabilite et de rigidite de la peau en composite. Suite a l'optimisation, la peau optimisee fut simplifiee afin de faciliter la fabrication et de respecter les regles de conception de Bombardier Aeronautique. Ce processus d'optimisation a permis de concevoir une peau en composite dont les deviations ou erreurs des formes obtenues etaient grandement reduites afin de repondre au mieux aux profils aerodynamiques optimises. Les analyses aerodynamiques realisees a partir de ces formes ont predit de bonnes ameliorations de la laminarite. Par la suite, une serie de validations analytiques fut realisee afin de valider l'integrite structurale de la peau en composite suivant les methodes generalement utilisees par Bombardier Aeronautique. D'abord, une analyse comparative par elements finis a permis de valider une rigidite equivalente de l'aile adaptative a la section d'aile d'origine. Le modele par elements finis fut par la suite mis en boucle avec des feuilles de calcul afin de valider la

  20. Biogenic Amines in Insect Antennae

    Directory of Open Access Journals (Sweden)

    Marianna I. Zhukovskaya

    2017-06-01

    Full Text Available Insect antenna is a multisensory organ, each modality of which can be modulated by biogenic amines. Octopamine (OA and its metabolic precursor tyramine (TA affect activity of antennal olfactory receptor neurons. There is some evidence that dopamine (DA modulates gustatory neurons. Serotonin can serve as a neurotransmitter in some afferent mechanosensory neurons and both as a neurotransmitter and neurohormone in efferent fibers targeted at the antennal vessel and mechanosensory organs. As a neurohormone, serotonin affects the generation of the transepithelial potential by sensillar accessory cells. Other possible targets of biogenic amines in insect antennae are hygro- and thermosensory neurons and epithelial cells. We suggest that the insect antenna is partially autonomous in the sense that biologically active substances entering its hemolymph may exert their effects and be cleared from this compartment without affecting other body parts.

  1. Trace Amines and Cocaine Abuse

    OpenAIRE

    Li, Jun-Xu

    2014-01-01

    Cocaine addiction remains a clinical challenge with no effective pharmacotherapy available. Trace amine associated receptor (TAAR) 1 represents a promising drug target for the modulation of dopaminergic system and stimulant abuse. This Viewpoint discusses the emerging data which strongly suggest that TAAR 1 functions as a molecular “brake” that controls the addiction-related effects of cocaine and could be a novel drug target for the development of efficacious pharmacothe...

  2. Amine promiscuity and toxicology analysis.

    Science.gov (United States)

    Lee, Esther C Y; Steeno, Gregory; Wassermann, Anne Mai; Zhang, Liying; Shah, Falgun; Price, David A

    2017-02-01

    Drug discovery programs often face challenges to obtain sufficient duration of action of the drug (i.e. seek longer half-lives). If the pharmacodynamic response is driven by free plasma concentration of the drug then extending the plasma drug concentration is a valid approach. Half-life is dependent on the volume of distribution, which in turn can be dependent upon the ionization state of the molecule. Basic compounds tend to have a higher volume of distribution leading to longer half-lives. However, it has been shown that bases may also have higher promiscuity. In this work, we describe an analysis of in vitro pharmacological profiling and toxicology data investigating the role of primary, secondary, and tertiary amines in imparting promiscuity and thus off-target toxicity. Primary amines are found to be less promiscuous in in vitro assays and have improved profiles in in vivo toxicology studies compared to secondary and tertiary amines. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Recommandations pour la qualité de l'eau au Canada: triallate

    National Research Council Canada - National Science Library

    Kent, R. A; Canada. Direction générale des sciences et de l'évaluation des écosystèmes. Direction de la santé des écosystèmes

    1992-01-01

    .... On a examine la documentation relative aux utilisations, au devenir et aux effets du triallate sur l'eau naturelle utilisee comme eau potable non traitee, sur la vie aquatique en eau douce, sur...

  4. Offre pour nos membres

    CERN Multimedia

    Staff Association

    2016-01-01

    Walibi Rhône-Alpes accueille son événement Halloween FreakShow le week-end du 15 et 16 octobre puis tous les jours du 20 octobre au 02 novembre 2016 ! ouverture prolongée jusqu’à 19h et feu d’artifices chaque soir 29, 30 et 31 octobre ! Loup-garou show; 1 labyrinthe; jeu de piste sur le parc (et nombreux lots à gagner); animations (sculpture sur citrouilles et maquillage) et d'autres surpises ! Tarifs pour nos membres : Entrée "Zone terrestre": 23 € au lieu de 29 €. Entrée gratuite pour les enfants de moins de 3 ans, avec accès aux attractions limité. Parking gratuit.

  5. Iridium-Catalyzed Condensation of Primary Amines To Form Secondary Amines

    DEFF Research Database (Denmark)

    Lorentz-Petersen, Linda Luise Reeh; Jensen, Paw; Madsen, Robert

    2009-01-01

    Symmetric secondary amines are readily obtained by heating a neat primary amine with 0.5 mol% of bis(dichloro[eta(5)-pentamethylcyclopentadienyl]iridium). The products are isolated by direct distillation in good yields.......Symmetric secondary amines are readily obtained by heating a neat primary amine with 0.5 mol% of bis(dichloro[eta(5)-pentamethylcyclopentadienyl]iridium). The products are isolated by direct distillation in good yields....

  6. Etude de la transition tribologique entre le fretting et le meso-fretting pour des materiaux de contact electrique

    Science.gov (United States)

    Gagnon, Daniel

    Dans les installations electriques, les contacts sont toujours soumis a des contraintes alternees ou a des micro-deplacements. Il en resulte une corrosion par fretting, phenomene defini comme un type de deterioration de la surface qui se produit lorsque deux materiaux en contact sont soumis a des mouvements microscopiques d'oscillations de tres faible amplitude (0 a 100 mum). Ceci a pour effet de provoquer une degradation de la resistance de contact et une interruption du passage du courant. Ce phenomene a des repercussions considerables sur le plan pratique puisque les micro-deplacements de pieces en contact peuvent etre causes par la dilatation thermique differentielle des metaux, par des vibrations mecaniques, par la relaxation des contraintes ou par l'echauffement des contacts lorsqu'on interrompt et retablit le courant. Nous avons donc dans le cadre de cette these etudie plusieurs aspects du fretting (0--100 mum) et du meso-fretting (100 a 1000 mum) pour differents materiaux de contact electrique. Des travaux experimentaux ont ete realises a partir de deux montages reproduisant divers aspects de la degradation par le fretting. Un premier montage de fretting de type bille-plaque a ete entierement developpe a l'ETS et un second montage, de type fil-plaque a ete utilise en collaboration avec Hydro Quebec IREQ a Varennes. Plusieurs techniques de mesures et d'analyse relevant tant du domaine de la mecanique du contact que de la metallurgie ont ete utilisees pour traiter les resultats. L'influence du courant sur le taux d'usure et la force de friction a ete examinee pour divers materiaux de contacts. Des essais de fatigue thermique et electrique ont ete realises sur divers materiaux et lubrifiants de contact. Il a ete demontre que pour le domaine entre 100 mum et 1000 mum, le taux d'usure n'est pas le meme de 0 a 100 mum et au dela de 1000 mum. La plupart des materiaux evalues montrent un stade de comportement intermediaire dont le debut se situe entre 100 mum et

  7. Intolerance to dietary biogenic amines : a review

    NARCIS (Netherlands)

    Jansen, SC; van Dusseldorp, M; Bottema, KC; Dubois, AEJ

    Objective: To evaluate the scientific evidence for purported intolerance to dietary biogenic amines. Data Sources: MEDLINE was searched for articles in the English language published between January 1966 and August 2001. The keyword biogenic amin* was combined with hypersens*, allergen intoler*, and

  8. Method for the production of primary amines

    NARCIS (Netherlands)

    Baldenius, Kai-Uwe; Ditrich, Klaus; Breurer, Michael; Navickas, Vaidotas; Janssen, Dick; Crismaru, Ciprian; Bartsch, Sebastian

    2014-01-01

    The present invention relates to a novel enzymatically catalyzed method for the production of aliphatic primary amines, which method comprises the enzymatic oxidation of a primary aliphatic alcohol catalyzed by an alcohol dehydrogenase, amination of the resulting oxocompound catalyzed by a

  9. Surface amination of poly(acrylonitrile)

    NARCIS (Netherlands)

    Hartwig, Andreas; Mulder, M.H.V.; Smolders, C.A.; Smolders, C.A.

    1994-01-01

    The surface amination of poly (acrylonitrile) by ammonia plasma treatment has been studied. Furthermore, two other surface modification techniques have been investigated, the plasma chemical decomposition of an amino group containing chemical (tris-(2-aminoethyl)amine) onto the polymer surface and

  10. Intolerance to dietary biogenic amines: A review

    NARCIS (Netherlands)

    Jansen, S.C.; Dusseldorp, M. van; Bottema, K.C.; Dubois, A.E.J.

    2003-01-01

    Objective: To evaluate the scientific evidence for purported intolerance to dietary biogenic amines. Data Sources: MEDLINE was searched for articles in the English language published between January 1966 and August 2001. The keyword biogenic amin* was combined with hypersens*, allerg*, intoler*, and

  11. Extraction of sulphates by long chain amines

    International Nuclear Information System (INIS)

    Boirie, Ch.

    1959-05-01

    The extraction of sulphuric acid by long chain amines in organic solution has been studied with a view to determining the value of the stability constants of the amine sulphates and bi-sulphates formed. We have concentrated chiefly on uranium sulphate and thorium sulphate. The formulae of the complexes extractable with amines have been established, as well as the corresponding dissociation constants. We have observed that for uranium sulphate the formula of the complex depends only on the nature of the amine, whereas for thorium this formula varies with the amine structure. From the formulae determined and the value of the constants calculated, we have been able to establish the best conditions for uranium and thorium extraction and also for a separation of these two elements. Finally we propose an application of this study to the determination of uranium in ores, where the separation of uranium by this method is particularly easy and complete. (author) [fr

  12. Informatique: tous pour un ... projet

    CERN Multimedia

    Delétraz, F; Requin, J-M

    2004-01-01

    "Pour des raisons de coût et d'efficacité, les chercheurs font de plus en plus travailler ensemble des ordinateurs éparpillés sur tous les continents. Pour faire avancer la science, tous les moyens et tous les réseaux sont bons" (1 page)

  13. Thermodynamics of mixtures containing amines

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Juan Antonio [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain)], E-mail: jagl@termo.uva.es; Mozo, Ismael; Garcia de la Fuente, Isaias; Cobos, Jose Carlos [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain); Riesco, Nicolas [Department of Chemical Engineering, Loughborough University, Loughborough, LE113TU Leicestershire (United Kingdom)

    2008-01-30

    Mixtures with dimethyl or trimethylpyridines and alkane, aromatic compound or 1-alkanol have been examined using different theories: DISQUAC, Flory, the concentration-concentration structure factor, S{sub CC}(0), or the Kirkwood-Buff formalism. DISQUAC represents fairly well the available experimental data, and improves theoretical calculations from Dortmund UNIFAC. Two important effects have been investigated: (i) the effect of increasing the number of methyl groups attached to the aromatic ring of the amine; (ii) the effect of modifying the position of the methyl groups in this ring. The molar excess enthalpy, H{sup E}, and the molar excess volume, V{sup E}, decrease in systems with alkane or methanol as follows: pyridine > 3-methylpyridine > 3,5-dimethylpyridine and pyridine > 2-methylpyridine > 2,4-dimethylpyridine > 2,4,6-trimethylpyridine, which has been attributed to a weakening of the amine-amine interactions in the same sequences. This is in agreement with the relative variation of the effective dipole moment, {mu}-bar, and of the differences between the boiling temperature of a pyridine base and that of the homomorphic alkane. For heptane solutions, the observed H{sup E} variation, H{sup E} (3,5-dimethylpyridine) > H{sup E} (2,4-dimethylpyridine) > H{sup E} (2,6-dimethylpyridine), is explained similarly. Calculations on the basis of the Flory model confirm that orientational effects become weaker in systems with alkane in the order: pyridine > methylpyridine > dimethylpyridine > trimethylpyridine. S{sub CC}(0) calculations show that steric effects increase with the number of CH{sub 3}- groups in the pyridine base, and that the steric effects exerted by methyl groups in positions 2 and 6 are higher than when they are placed in positions 3 and 5. The hydrogen bond energy in methanol mixtures is independent of the pyridine base, and it is estimated to be -35.2 kJ mol{sup -1}. Heterocoordination in these solutions is due in part to size effects. Their

  14. Tunable, chemoselective amination via silver catalysis.

    Science.gov (United States)

    Rigoli, Jared W; Weatherly, Cale D; Alderson, Juliet M; Vo, Brian T; Schomaker, Jennifer M

    2013-11-20

    Organic N-containing compounds, including amines, are essential components of many biologically and pharmaceutically important molecules. One strategy for introducing nitrogen into substrates with multiple reactive bonds is to insert a monovalent N fragment (nitrene or nitrenoid) into a C-H bond or add it directly to a C═C bond. However, it has been challenging to develop well-defined catalysts capable of promoting predictable and chemoselective aminations solely through reagent control. Herein, we report remarkable chemoselective aminations that employ a single metal (Ag) and a single ligand (phenanthroline) to promote either aziridination or C-H insertion by manipulating the coordination geometry of the active catalysts.

  15. Incidence of biogenic amines in foods implications for the Gambia ...

    African Journals Online (AJOL)

    Amines are found in food. Biogenic amines are a class of amines, which result from decarboxylation. They are food quality indicators. Health-wise biogenic amines play positive roles and have adverse effects as well; they are a public health concern. Certain conditions make it possible for them to be produced. These could ...

  16. Enquete ethnobotanique sur les plantes antipaludiques utilisees ...

    African Journals Online (AJOL)

    Mots clés: Enquête ethnobotanique, plantes antipaludiques anti- vectorielles, Anopheles sp, Togo. English Title: Ethnobotanical survey of mosquito repellent medicinal plants of Togo. English Abstract. The new ethnobotanical method named ATRM (Purchase in Triplet of Medicinal Recipes, in English) coupled with the semi ...

  17. Graphite Oxide and Aromatic Amines : Size Matters

    NARCIS (Netherlands)

    Spyrou, Konstantinos; Calvaresi, Matteo; Diamanti, Evmorfi A. K.; Tsoufis, Theodoros; Gournis, Dimitrios; Rudolf, Petra; Zerbetto, Francesco

    2015-01-01

    Experimental and theoretical studies are performed in order to illuminate, for first time, the intercalation mechanism of polycyclic aromatic molecules into graphite oxide. Two representative molecules of this family, aniline and naphthalene amine are investigated. After intercalation, aniline

  18. Anodic selective functionalization of cyclic amine derivatives

    OpenAIRE

    Onomura, Osamu

    2012-01-01

    Anodic reactions are desirable methods from the viewpoint of Green Chemistry, since no toxic oxidants are necessary for the oxidation of organic molecules. This review introduces usefulness of anodic oxidation and successive reaction for selective functionalization of cyclic amine derivatives.

  19. Selective N-alkylation of amines using nitriles under hydrogenation conditions: facile synthesis of secondary and tertiary amines.

    Science.gov (United States)

    Ikawa, Takashi; Fujita, Yuki; Mizusaki, Tomoteru; Betsuin, Sae; Takamatsu, Haruki; Maegawa, Tomohiro; Monguchi, Yasunari; Sajiki, Hironao

    2012-01-14

    Nitriles were found to be highly effective alkylating reagents for the selective N-alkylation of amines under catalytic hydrogenation conditions. For the aromatic primary amines, the corresponding secondary amines were selectively obtained under Pd/C-catalyzed hydrogenation conditions. Although the use of electron poor aromatic amines or bulky nitriles showed a lower reactivity toward the reductive alkylation, the addition of NH(4)OAc enhanced the reactivity to give secondary aromatic amines in good to excellent yields. Under the same reaction conditions, aromatic nitro compounds instead of the aromatic primary amines could be directly transformed into secondary amines via a domino reaction involving the one-pot hydrogenation of the nitro group and the reductive alkylation of the amines. While aliphatic amines were effectively converted to the corresponding tertiary amines under Pd/C-catalyzed conditions, Rh/C was a highly effective catalyst for the N-monoalkylation of aliphatic primary amines without over-alkylation to the tertiary amines. Furthermore, the combination of the Rh/C-catalyzed N-monoalkylation of the aliphatic primary amines and additional Pd/C-catalyzed alkylation of the resulting secondary aliphatic amines could selectively prepare aliphatic tertiary amines possessing three different alkyl groups. According to the mechanistic studies, it seems reasonable to conclude that nitriles were reduced to aldimines before the nucleophilic attack of the amine during the first step of the reaction.

  20. General Dialdehyde Click Chemistry for Amine Bioconjugation.

    Science.gov (United States)

    Elahipanah, Sina; O'Brien, Paul J; Rogozhnikov, Dmitry; Yousaf, Muhammad N

    2017-05-17

    The development of methods for conjugating a range of molecules to primary amine functional groups has revolutionized the fields of chemistry, biology, and material science. The primary amine is a key functional group and one of the most important nucleophiles and bases used in all of synthetic chemistry. Therefore, tremendous interest in the synthesis of molecules containing primary amines and strategies to devise chemical reactions to react with primary amines has been at the core of chemical research. In particular, primary amines are a ubiquitous functional group found in biological systems as free amino acids, as key side chain lysines in proteins, and in signaling molecules and metabolites and are also present in many natural product classes. Due to its abundance, the primary amine is the most convenient functional group handle in molecules for ligation to other molecules for a broad range of applications that impact all scientific fields. Because of the primary amine's central importance in synthetic chemistry, acid-base chemistry, redox chemistry, and biology, many methods have been developed to efficiently react with primary amines, including activated carboxylic acids, isothiocyanates, Michael addition type systems, and reaction with ketones or aldehydes followed by in situ reductive amination. Herein, we introduce a new traceless, high-yield, fast click-chemistry method based on the rapid and efficient trapping of amine groups via a functionalized dialdehyde group. The click reaction occurs in mild conditions in organic solvents or aqueous media and proceeds in high yield, and the starting dialdehyde reagent and resulting dialdehyde click conjugates are stable. Moreover, no catalyst or dialdehyde-activating group is required, and the only byproduct is water. The initial dialdehyde and the resulting conjugate are both straightforward to characterize, and the reaction proceeds with high atom economy. To demonstrate the broad scope of this new click

  1. Enhancing amine terminals in an amine-deprived collagen matrix.

    LENUS (Irish Health Repository)

    Tiong, William H C

    2008-10-21

    Collagen, though widely used as a core biomaterial in many clinical applications, is often limited by its rapid degradability which prevents full exploitation of its potential in vivo. Polyamidoamine (PAMAM) dendrimer, a highly branched macromolecule, possesses versatile multiterminal amine surface groups that enable them to be tethered to collagen molecules and enhance their potential. In this study, we hypothesized that incorporation of PAMAM dendrimer in a collagen matrix through cross-linking will result in a durable, cross-linked collagen biomaterial with free -NH 2 groups available for further multi-biomolecular tethering. The aim of this study was to assess the physicochemical properties of a G1 PAMAM cross-linked collagen matrix and its cellular sustainability in vitro. Different amounts of G1 PAMAM dendrimer (5 or 10 mg) were integrated into bovine-derived collagen matrices through a cross-linking process, mediated by 5 or 25 mM 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) in 5 mM N-hydroxysuccinimide (NHS) and 50 mM 2-morpholinoethane sulfonic acid buffer at pH 5.5. The physicochemical properties of resultant matrices were investigated with scanning electron microscopy (SEM), collagenase degradation assay, differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectra, and ninhydrin assay. Cellular sustainability of the matrices was assessed with Alamar Blue assay and SEM. There was no significant difference in cellular behavior between the treated and nontreated groups. However, the benefit of incorporating PAMAM in the cross-linking reaction was limited when higher concentrations of either agent were used. These results confirm the hypothesis that PAMAM dendrimer can be incorporated in the collagen cross-linking process in order to modulate the properties of the resulting cross-linked collagen biomaterial with free -NH 2 groups available for multi-biomolecular tethering.

  2. PEGylated bioreducible poly(amido amine)s for non-viral gene delivery

    NARCIS (Netherlands)

    Lin, C.; Engbersen, Johannes F.J.

    2011-01-01

    A facile method for PEGylated bioreducible poly(amido amine)s is described by a one-pot Michael-type addition polymerization of N, N′-cystaminebisacrylamide (CBA) with a mixture of 4-amino-1-butanol (ABOL) and mono-tert-butoxycarbonyl (Boc) PEG diamine. By this approach, two Boc-amino-PEGylated

  3. Bioreducible poly(amido amine)s for non-viral gene delivery

    NARCIS (Netherlands)

    Lin, C.

    2008-01-01

    This thesis describes the design and development of bioreducible poly(amido amine)s as non-viral vectors for gene delivery in vitro and in vivo. The structural influences of these polymers on their physico-chemical properties and gene delivery properties, transfection capability and cytotoxicity in

  4. Biogenic amines in meat and meat products.

    Science.gov (United States)

    Ruiz-Capillas, Claudia; Jiménez-Colmenero, Francisco

    2004-01-01

    It has been recognized for some time that biogenic amines occur in a wide range of foods, among them meat and meat products. Meat is an important component of the diet in developed countries. The presence of these amines in food is of interest for two reasons: firstly, for toxicological reasons, in the sense that high levels of dietary biogenic amines can be toxic for certain consumers, and secondly, for their role as possible quality indicators. Based on these two premises, the present article offers a new analysis on aspects of toxicology and on the use of biogenic amines as a quality control method, as well as on their presence in meat and meat products. The article focuses particularly on factors affecting the production of biogenic amines, with reference to various parameters relating to microorganisms, meat raw materials, and processing conditions. A better understanding of the factors determining their formation (i.e., microorganisms, raw materials used, and technological processes applied) and their effects could lead to ways of controlling their production, limiting their presence in the end product, and hence, rendering them less toxic.

  5. BIOGENIC AMINES CONTENT IN DIFFERENT WINE SAMPLES

    Directory of Open Access Journals (Sweden)

    Attila Kántor

    2015-02-01

    Full Text Available Twenty-five samples of different Slovak wines before and after filtration were analysed in order to determine the content of eight biogenic amines (tryptamine, phenylalanine, putrescine, cadaverine, histamine, tyramine, spermidine and spermine. The method involves extraction of biogenic amines from wine samples with used dansyl chloride. Ultra-high performance liquid chromatography (UHPLC was used for determination of biogenic amines equipped with a Rapid Resolution High Definition (RRHD, DAD detectors and Extend-C18 LC column (50 mm x 3.0 mm ID, 1.8 μm particle size. In this study the highest level of biogenic amine in all wine samples represent tryptamine (TRM with the highest content 170.9±5.3 mg/L in Pinot Blanc wine. Phenylalanine (PHE cadaverine (CAD, histamine (HIS and spermidine (SPD were not detected in all wines; mainly SPD was not detected in 16 wines, HIS not detected in 14 wines, PHE and CAD not detected in 2 wines. Tyramine (TYR, spermine (SPN and putrescine (PUT were detected in all wines, but PUT and SPN in very low concentration. The worst wine samples with high biogenic amine content were Saint Laurent (BF, Pinot Blanc (S and Pinot Noir (AF.

  6. Dvorak. Concerto pour violoncelle / Francis Dresel

    Index Scriptorium Estoniae

    Dresel, Francis

    1992-01-01

    Uuest heliplaadist "Dvorak. Concerto pour violoncelle; Schumann: Concerto pour violoncelle. Orchestre Symphonique d'Estonie, Orchestre Symphonique de la Radio TV d'URSS, Neeme Järvi" Vogue "Archives Sovietiques" 651033 1978

  7. Calcite Twins, a Tool for Tectonic Studies in Thrust Belts and Stable Orogenic Forelands Les macles de la calcite, un outil pour les études tectoniques dans les chaînes plissées et les avant-pays peu déformés des orogènes

    Directory of Open Access Journals (Sweden)

    Lacombe O.

    2010-10-01

    Full Text Available Calcite twins have been used for a long time as indicators of stress/strain orientations and magnitudes. Recent developments during the last 15 years point toward significant improvements of existing techniques as well as new applications of calcite twin analysis in thrust belts and forelands. This paper summarizes the principles of the most common techniques in this tectonic field and illustrates some aspects of the use of calcite twins to constrain not only stress/strain orientations and magnitudes, but also to some extent paleotemperature or paleoburial in orogenic forelands. This review is based in a large part on the studies that I conducted in various geological settings such as the forelands of Taiwan, Pyrenees, Zagros, Rockies and Albanides orogens. The contribution of calcite twin analysis to the understanding of the intraplate stress transmission away from plate boundaries is also emphasized. Les macles de la calcite sont utilisees depuis longtemps comme indicateurs de paleocontraintes et comme marqueurs de la deformation finie, en orientations comme en grandeurs. Au cours des 15 dernieres annees, des ameliorations importantes des methodes d’analyses existantes ont ete realisees et ont donne lieu a de nouvelles applications dans les chaines plissees et les avant-pays peu deformes des orogenes. Cet article resume le principe des methodes les plus utilisees en tectonique et illustre quelques apports de l’analyse des macles de la calcite pour la caracterisation non seulement des orientations et des grandeurs des paleocontraintes et de la deformation finie, mais egalement dans une certaine mesure de la paleotemperature et du paleoenfouissement. Cette revue se fonde en grande partie sur les etudes regionales que j’ai effectuees dans des contextes geologiques varies, comme les avant-pays des chaines de Taiwan, des Pyrenees, du Zagros, des Rocheuses et des Albanides. Cet article discutera egalement la contribution de l’etude des

  8. Mise au point du rheometre a cisaillement annulaire pour l'etude de rheologie d'un mastic bitumineux avec verre incorpore =

    Science.gov (United States)

    El Mansouri, Souleimane

    Dans le domaine viscoelastique lineaire (VEL, domaine des petites deformations), le comportement thermomecanique du bitume et du mastic bitumineux (melange uniforme de bitume et de fillers) a ete caracterise au Laboratoire des Chaussees et Materiaux Bitumineux (LCMB) de l'Ecole de technologie superieure (ETS) avec l'appui de nos partenaires externes : la Societe des Alcools du Quebec (SAQ) et Eco Entreprises Quebec (EEQ). Les proprietes rheologiques des bitumes et des mastics ont ete mesurees grâce a un nouvel outil d'investigation appele, Rheometre a Cisaillement Annulaire (RCA), sous differentes conditions de chargement. Cet appareil permet non seulement de solliciter des eprouvettes de tailles importantes par rapport a celles utilisees lors des essais classiques, mais aussi d'effectuer des essais en conditions quasi-homogenes, ce qui permet de donner acces a la loi de comportement des materiaux. Les essais sont realises sur une large gamme de temperatures et de frequences (de -15 °C a 45°C et de 0,03Hz a 10 Hz). Cette etude a ete menee principalement pour comparer le comportement d'un bitume avec celui d'un mastic bitumineux dans le domaine des petites deformations. neanmoins, dans une seconde perspective, on s'interesse a l'influence des fillers de verre de post-consommation sur le comportement d'un mastic a faibles niveaux de deformations en comparant l'evolution des modules complexes de cisaillements (G*) d'un mastic avec fillers de verre et un mastic avec fillers conventionnels (calcaire). Enfin, le modele analogique 2S2P1D est utilise pour simuler le comportement viscoelastique lineaire des bitumes et des mastics bitumineux testes lors de la campagne experimentale.

  9. Catalyst for hydrogen-amine D exchange

    International Nuclear Information System (INIS)

    Holtslander, W.J.; Johnson, R.E.

    1976-01-01

    A process is claimed for deuterium isotopic enrichment (suitable for use in heavy water production) by amine-hydrogen exchange in which the exchange catalyst comprises a mixture of alkyl amides of two metals selected from the group consisting of the alkali metals. Catalyst mixtures comprising at least one of the alkali amides of lithium and potassium are preferred. At least one of the following benefits are obtained: decreased hydride formation, decreased thermal decomposition of alkyl amide, increased catalyst solubility in the amine phase, and increased exchange efficiency. 11 claims

  10. Base metal dehydrogenation of amine-boranes

    Science.gov (United States)

    Blacquiere, Johanna Marie [Ottawa, CA; Keaton, Richard Jeffrey [Pearland, TX; Baker, Ralph Thomas [Los Alamos, NM

    2009-06-09

    A method of dehydrogenating an amine-borane having the formula R.sup.1H.sub.2N--BH.sub.2R.sup.2 using base metal catalyst. The method generates hydrogen and produces at least one of a [R.sup.1HN--BHR.sup.2].sub.m oligomer and a [R.sup.1N--BR.sup.2].sub.n oligomer. The method of dehydrogenating amine-boranes may be used to generate H.sub.2 for portable power sources, such as, but not limited to, fuel cells.

  11. 40 CFR 721.640 - Amine substituted metal salts.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Amine substituted metal salts. 721.640... Substances § 721.640 Amine substituted metal salts. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as amine substituted metal salts...

  12. Purification and characterization of amine oxidase from Vigna ...

    African Journals Online (AJOL)

    Amine oxidases (AO) are a group of enzymes that catalyze oxidative deamination of various amines and thus are of potential use in analytical applications. Amine oxidase from five-day-old Vigna mungo L. seedlings (VAO) was purified using ammonium sulfate fractionation and Q-Sepharose chromatography to 544 ...

  13. When It Rains, It Pours

    Science.gov (United States)

    Mills, Linda

    2012-01-01

    "It's raining, it's pouring, the old man is snoring!" "The itsy, bitsy spider crawled up the waterspout, down came the rain and washed the spider out. Out came the sun and dried up all the rain, and the itsy, bitsy spider went up the spout again." What do children's nursery rhymes have to do with the school library? The author begins by telling a…

  14. Oxidative nucleophilic aromatic amination of nitrobenzenes

    Czech Academy of Sciences Publication Activity Database

    Khutorianskyi, Viktor V.; Sonawane, Manoj R.; Pošta, Martin; Klepetářová, Blanka; Beier, Petr

    2016-01-01

    Roč. 52, č. 45 (2016), s. 7237-7240 ISSN 1359-7345 R&D Projects: GA ČR GAP207/12/0072 Institutional support: RVO:61388963 Keywords : C-H amination * bond formation * substitution Subject RIV: CC - Organic Chemistry Impact factor: 6.319, year: 2016

  15. PEMIKIRAN QASIM AMIN TENTANG EMANSIPASI WANITA

    Directory of Open Access Journals (Sweden)

    Eliana Siregar

    2017-02-01

    Full Text Available The aim of this research is to explore the idea belong to Qosim Amin "Tahrir al-Mar'ah" as the main theme  of Qasim Amin reformation is an idea that is based on the spirit of liberation and empowerment of women. This idea emerged as a reflection and manifestation of concern intellectualism against the reality of Egyptian woman, who had reached the threshold of tolerance limits area . By using library research method, this research used book, journal, and others as the data resouces. As the cosequency, content analysis was used to analyse the data. Qasim Amin stresses that Islam should be granted rights of women in proportion tha is the right in education and acquire  same right in tasting educational right between men and women, because Islaic value is full of fairness and required the responsibility to Allah. The resut of this research shows that Qosim Amin concern on vision and educational issues in his Idea. There was an awareness of Egytianson the important position of women on education, chance of women to wear veily the government’s attention on the revision of religions justice. These changes have in fired the Egypt women todays.

  16. Fate and biodegradability of sulfonated aromatic amines

    NARCIS (Netherlands)

    Tan, N.C.G.; Leeuwen, van A.; Voorthuizen, van E.M.; Slenders, P.; Prenafeta, F.X.; Temmink, H.; Lettinga, G.; Field, J.A.

    2005-01-01

    Ten sulfonated aromatic amines were tested for their aerobic and anaerobic biodegradability and toxicity potential in a variety of environmental inocula. Of all the compounds tested, only two aminobenzenesulfonic acid (ABS) isomers, 2- and 4-ABS, were degraded. The observed degradation occurred only

  17. Microbiological, physicochemical properties and biogenic amine ...

    African Journals Online (AJOL)

    Thirty three strained yoghurt samples were collected from local open markets in different provinces of Turkey (Afyon [AF], Aydın [AY], Burdur [B], Isparta [I] and Muğla [M]). Physicochemical and microbiological properties, as well as biogenic amine content, were examined in each of the samples. The dry matter (17.90 to ...

  18. New adducts of Lapachol with primary amines

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Mirelly D.F.; Litivack-Junior, Jose T.; Antunes, Roberto V.; Silva, Tania M.S.; Camara, Celso A., E-mail: ccelso@dq.ufrpe.b [Universidade Federal Rural de Pernambuco (UFRPE), Recife, PE (Brazil). Dept. de Quimica

    2011-07-01

    New adducts of lapachol with neat primary aliphatic amines were obtained in a solvent-free reaction in good to reasonable yields (52 to 88%), at room temperature. The new compounds containing a phenazine moiety were obtained from suitable functionalized aminoalkyl compounds, including ethanolamine, 3-propanolamine, 2-methoxy-ethylamine, 3-methoxy-propylamine, n-butylamine and 2-phenetylamine. (author)

  19. Uranium diphosphonates templated by interlayer organic amines

    International Nuclear Information System (INIS)

    Nelson, Anna-Gay D.; Alekseev, Evgeny V.; Albrecht-Schmitt, Thomas E.; Ewing, Rodney C.

    2013-01-01

    The hydrothermal treatment of uranium trioxide and methylenediphosphonic acid with a variety of amines (2,2-dipyridyl, triethylenediamine, ethylenediamine, and 1,10-phenanthroline) at 200 °C results in the crystallization of a series of layered uranium diphosphonate compounds, [C 10 H 9 N 2 ]{UO 2 (H 2 O)[CH 2 (PO 3 )(PO 3 H)]} (Ubip2), [C 6 H 14 N 2 ]{(UO 2 ) 2 [CH 2 (PO 3 )(PO 3 H)] 2 ·2H 2 O} (UDAB), [C 2 H 10 N 2 ] 2 {(UO 2 ) 2 (H 2 O) 2 [CH 2 (PO 3 ) 2 ] 2 ·0.5H 2 O} (Uethyl), and [C 12 H 9 N 2 ]{UO 2 (H 2 O)[CH 2 (PO 3 )(PO 3 H)]} (Uphen). The crystal structures of the compounds are based on UO 7 units linked by methylenediphosphonate molecules to form two-dimensional anionic sheets in Ubip2 and UDAB, and one-dimensional anionic chains in Uethyl and Uphen, which are charge balanced by protonated amine molecules. Interaction of the amine molecules with phosphonate oxygens and water molecules results in extensive hydrogen bonding in the interlayer. These amine molecules serve both as structure-directing agents and charge-balancing cations for the anionic uranium phosphonate sheets and chains in the formation of the different coordination geometries and topologies of each structure. Reported herein are the syntheses, structural and spectroscopic characterization of the synthesized compounds. - Graphical abstract: The Raman spectra of the synthesized compounds and an illustration of the stacking of the layers with the diprotonated triethylenediamine molecules in [C 6 H 14 N 2 ]{(UO 2 ) 2 [CH 2 (PO 3 )(PO 3 H)] 2 ·2H 2 O} UDAB. Solvent water molecules are removed for clarity. The corresponding Raman spectra for the complexes synthesized is also shown. The structure is constructed from UO 7 pentagonal bipyramids (yellow), oxygen=red, phosphorus=magenta, carbon=black, and nitrogen=blue. Highlights: ► Organic amines act both as charge-balancing and as structure-directing agents. ► Extensive hydrogen bonding interactions with solvent water molecules and amines

  20. Antibacterial and antioxidative activity of O-amine functionalized chitosan.

    Science.gov (United States)

    Tamer, Tamer M; Hassan, Mohamed A; Omer, Ahmed M; Valachová, Katarína; Eldin, Mohamed S Mohy; Collins, Maurice N; Šoltés, Ladislav

    2017-08-01

    Cinnamaldehyde was immobilized to O-amine functionalized chitosan via a coupling reaction. Fourier transform infrared spectroscopy confirmed N-cinnamyl substitution. Wetting analyses demonstrate more hydrophobicity in the N-cinnamyl substituted O-amine functionalized chitosan compared to chitosan or unsubstituted O-amine functionalized chitosan. Thermal gravimetric analysis and differential scanning calorimetry demonstrates that the prepared N-cinnamyl substituted O-amine functionalized chitosan exhibits higher thermostability than unmodified chitosan at temperatures in which polysaccharides are commonly stored and utilised. The N-cinnamyl substituted O-amine functionalized chitosan, against four different bacteria strains [two gram-positive (Staphylococcus aureus and Bacillus cereus) and two gram-negative (Escherichia coli and Pseudomonas aeruginosa)], displays promotion of inhibition activity against these bacterial strains. Finally, the antioxidative activity of the N-cinnamyl substituted O-amine functionalized chitosan was compared with those activities of chitosan and O-amine functionalized chitosan. This was evaluated by uninhibited and inhibited hyaluronan degradation and ABTS assay. The N-cinnamyl substituted O-amine functionalized chitosan shows a lower activity towards donating a hydrogen radical compared to chitosan or O-amine functionalized chitosan. On the other hand, the N-cinnamyl substituted O-amine functionalized chitosan exhibited a higher ability to scavenge the ABTS + cation radical compared to chitosan and O-amine functionalized chitosan. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Metabolism and Biomarkers of Heterocyclic Aromatic Amines in Molecular Epidemiology Studies: Lessons Learned from Aromatic Amines

    Science.gov (United States)

    2011-01-01

    Aromatic amines and heterocyclic aromatic amines (HAAs) are structurally related classes of carcinogens that are formed during the combustion of tobacco or during the high-temperature cooking of meats. Both classes of procarcinogens undergo metabolic activation by N-hydroxylation of the exocyclic amine group, to produce a common proposed intermediate, the arylnitrenium ion, which is the critical metabolite implicated in toxicity and DNA damage. However, the biochemistry and chemical properties of these compounds are distinct and different biomarkers of aromatic amines and HAAs have been developed for human biomonitoring studies. Hemoglobin adducts have been extensively used as biomarkers to monitor occupational and environmental exposures to a number of aromatic amines; however, HAAs do not form hemoglobin adducts at appreciable levels and other biomarkers have been sought. A number of epidemiologic studies that have investigated dietary consumption of well-done meat in relation to various tumor sites reported a positive association between cancer risk and well-done meat consumption, although some studies have shown no associations between well-done meat and cancer risk. A major limiting factor in most epidemiological studies is the uncertainty in quantitative estimates of chronic exposure to HAAs and, thus, the association of HAAs formed in cooked meat and cancer risk has been difficult to establish. There is a critical need to establish long-term biomarkers of HAAs that can be implemented in molecular epidemioIogy studies. In this review article, we highlight and contrast the biochemistry of several prototypical carcinogenic aromatic amines and HAAs to which humans are chronically exposed. The biochemical properties and the impact of polymorphisms of the major xenobiotic-metabolizing enzymes on the biological effects of these chemicals are examined. Lastly, the analytical approaches that have been successfully employed to biomonitor aromatic amines and HAAs, and

  2. Development of a general non-noble metal catalyst for the benign amination of alcohols with amines and ammonia.

    Science.gov (United States)

    Cui, Xinjiang; Dai, Xingchao; Deng, Youquan; Shi, Feng

    2013-03-11

    The N-alkylation of amines or ammonia with alcohols is a valuable route for the synthesis of N-alkyl amines. However, as a potentially clean and economic choice for N-alkyl amine synthesis, non-noble metal catalysts with high activity and good selectivity are rarely reported. Normally, they are severely limited due to low activity and poor generality. Herein, a simple NiCuFeOx catalyst was designed and prepared for the N-alkylation of ammonia or amines with alcohol or primary amines. N-alkyl amines with various structures were successfully synthesized in moderate to excellent yields in the absence of organic ligands and bases. Typically, primary amines could be efficiently transformed into secondary amines and N-heterocyclic compounds, and secondary amines could be N-alkylated to synthesize tertiary amines. Note that primary and secondary amines could be produced through a one-pot reaction of ammonia and alcohols. In addition to excellent catalytic performance, the catalyst itself possesses outstanding superiority, that is, it is air and moisture stable. Moreover, the magnetic property of this catalyst makes it easily separable from the reaction mixture and it could be recovered and reused for several runs without obvious deactivation. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Conception et calibration d'un sonoreacteur pour l'oxydation de la cellulose par le systeme TEMPO/NaOCl/NaBr

    Science.gov (United States)

    Paquin, Michel

    grande consommation d'energie et de reactif qui rend le procede difficilement accessible au milieu industriel. L'utilisation des ultrasons lors de la reaction d'oxydation permet de reduire de 50% le temps de reaction et d'autant la consommation de produits chimiques. Actuellement le processus d'oxydation s'effectue en mode discontinu pour une quantite de 20 grammes de pate dans un reacteur en verre dans un bain a ultrason. L'objectif principal de ce travail est d'elaborer un sonoreacteur en mode semi-continu afin d'etre en mesure de transferer une reaction d'oxydation du mode discontinu en mode semi-continu. Le transfert de reaction sera effectue en realisant la calibration de l'activite acoustique des deux differents reacteurs, discontinu et semi-continu, par la methode de Weissler. La methode de Weissler quantifie le taux de production radicalaire en mesurant la formation d'iode moleculaire d'une solution aqueuse d'iodure de potassium sous ultrason. Suite a sa calibration, le sonoreacteur pilote (mode semi-continu) a demontre une augmentation de la production radicalaire de 683 % a 170 kHz en comparaison avec l'utilisation d'un bain a ultrason a la meme frequence. Lors de la reaction d'oxydation, la puissance optimale utilisee dans le bain a ultrason a 170 kHz est de 1000 W. La puissance utilisee selon les resultats de calibration obtenue dans le sonoreacteur pilote est de 125 W soit une diminution de l'energie appliquee de 87,5 %. Lors de la reaction d'oxydation, le taux de production des groupements carboxylates est de 2,6 mmol COOH kg/min dans le bain a ultrason et de 6,87 mmol COOH kg/min dans le sonoreacteur pilote soit une augmentation de 164% du taux de formation. Selon les resultats obtenus, l'utilisation d'un sonoreacteur en mode continu peut etre envisageable pour la reaction d'oxydation de la cellulose par le systeme TEMPO-NaOCl-NaBr en industrie au niveau industriel.

  4. Deuterium exchange between hydrofluorocarbons and amines

    International Nuclear Information System (INIS)

    Hammond, W.B.; Bigeleisen, J.; Tuccio, S.A.

    1983-01-01

    The invention consists of a process for obtaining a compound enriched in deuterium which comprises the known method of exposing a gaseous hydrofluorocarbon to infrared laser radiation of a predetermined frequency to selectively cause a chemical reaction involving hydrofluorocarbon molecules containing deuterium without substantially affecting hydrofluorocarbon molecules not containing deuterium, thereby producing, as reaction products, a compound enriched in deuterium and hydrofluorocarbon depleted in deuterium; combined with a new method, which comprises enriching the deuterium content of the depleted hydrofluorocarbon by contacting the depleted hydrofluorocarbon with an alkali metal amide and an amine having a concentration of deuterium at least that which will yield an increase in deuterium concentration of the hydrofluorocarbon upon equilibration, whereby the amine becomes depleted in deuterium

  5. Organic chemistry. Strain-release amination.

    Science.gov (United States)

    Gianatassio, Ryan; Lopchuk, Justin M; Wang, Jie; Pan, Chung-Mao; Malins, Lara R; Prieto, Liher; Brandt, Thomas A; Collins, Michael R; Gallego, Gary M; Sach, Neal W; Spangler, Jillian E; Zhu, Huichin; Zhu, Jinjiang; Baran, Phil S

    2016-01-15

    To optimize drug candidates, modern medicinal chemists are increasingly turning to an unconventional structural motif: small, strained ring systems. However, the difficulty of introducing substituents such as bicyclo[1.1.1]pentanes, azetidines, or cyclobutanes often outweighs the challenge of synthesizing the parent scaffold itself. Thus, there is an urgent need for general methods to rapidly and directly append such groups onto core scaffolds. Here we report a general strategy to harness the embedded potential energy of effectively spring-loaded C-C and C-N bonds with the most oft-encountered nucleophiles in pharmaceutical chemistry, amines. Strain-release amination can diversify a range of substrates with a multitude of desirable bioisosteres at both the early and late stages of a synthesis. The technique has also been applied to peptide labeling and bioconjugation. Copyright © 2016, American Association for the Advancement of Science.

  6. Catalyst for hydrogen-amine D exchange

    International Nuclear Information System (INIS)

    Holtslander, W.J.; Johnson, R.E.

    1977-01-01

    In a process for enrichment of deuterium by contacting hydrogen with an amine (such as methylamine), an alkali metal amide (such as potassium methylamide) is used as a catalyst. The present improvement is to use a mixture of two metal amides (e.g. lithium methylamide plus potassium methylamide) in order to prevent precipitation of a hydride and to reduce thermal decomposition of the catalyst. (NDH)

  7. Whole cell biotransformation for reductive amination reactions

    OpenAIRE

    Klatte, Stephanie; Lorenz, Elisabeth; Wendisch, Volker F

    2013-01-01

    Whole cell biotransformation systems with enzyme cascading increasingly find application in biocatalysis to complement or replace established chemical synthetic routes for production of, e.g., fine chemicals. Recently, we established an Escherichia coli whole cell biotransformation system for reductive amination by coupling a transaminase and an amino acid dehydrogenase with glucose catabolism for cofactor recycling. Transformation of 2-keto-3-methylvalerate to l-isoleucine by E. coli cells w...

  8. Asymmetric Aminalization via Cation-Binding Catalysis

    DEFF Research Database (Denmark)

    Park, Sang Yeon; Liu, Yidong; Oh, Joong Suk

    2018-01-01

    Asymmetric cation-binding catalysis, in principle, can generate "chiral" anionic nucleophiles, where the counter cations are coordinated within chiral environments. Nitrogen-nucleophiles are intrinsically basic, therefore, its use as nucleophiles is often challenging and limiting the scope...... of the reaction. Particularly, a formation of configurationally labile aminal centers with alkyl substituents has been a formidable challenge due to the enamine/imine equilibrium of electrophilic substrates. Herein, we report enantioselective nucleophilic addition reactions of potassium phthalimides to Boc-protected...

  9. Rett syndrome - Stimulation of endogenous biogenic amines

    Science.gov (United States)

    Pelligra, R.; Norton, R. D.; Wilkinson, R.; Leon, H. A.; Matson, W. R.

    1992-01-01

    Transient hypercapnic hyperoxemia was induced in two Rett syndrome children by the administration of a gaseous mixture of 80 percent O2 and 20 percent CO2. Time course studies of neurotransmitters and their metabolites showed an immediate and marked increase in central biogenic amine turnover following inhalation of the gas mixture. The increased turnover of biogenic amines was associated with improved clinical changes. This suggests a coupled relationship and provides further support for an etiological role of neurotransmitter dysfunction in Rett syndrome. In a complementary study, elevation of pulmonary CO2 by application of a simple rebreathing device resulted in improvement of abnormal blood gases and elimination of the Cheyne-Stokes-like respiratory pattern of the Rett syndrome. Near normalization of the EEG occurred when a normal respiratory pattern was imposed by means of a respirator. Taken together, these results lead to the preliminary conclusion that cerebral hypoxemia secondary to abnormal respiratory function may contribute to diminished production of biogenic amines in Rett syndrome.

  10. Comparison of kinetic properties of amine oxidases from sainfoin and lentil and immunochemical characterization of copper/quinoprotein amine oxidases.

    Science.gov (United States)

    Zajoncová, L; Frébort, I; Luhová, L; Sebela, M; Galuszka, P; Pec, P

    1999-01-01

    Kinetic properties of novel amine oxidase isolated from sainfoin (Onobrychis viciifolia) were compared to those of typical plant amine oxidase (EC 1.4.3.6) from lentil (Lens culinaris). The amine oxidase from sainfoin was active toward substrates, such as 1,5-diaminopentane (cadaverine) with K(m) of 0.09 mM and 1,4-diaminobutane (putrescine) with K(m) of 0.24 mM. The maximum rate of oxidation for cadaverine at saturating concentration was 2.7 fold higher than that of putrescine. The amine oxidase from lentil had the maximum rate for putrescine comparable to the rate of sainfoin amine oxidase with the same substrate. Both amine oxidases, like other plant Cu-amine oxidases, were inhibited by substrate analogs (1,5-diamino-3-pentanone, 1,4-diamino-2-butanone and aminoguanidine), Cu2+ chelating agents (diethyltriamine, 1,10-phenanthroline, 8-hydroxyquinoline, 2,2'-bipyridyl, imidazole, sodium cyanide and sodium azide), some alkaloids (L-lobeline and cinchonine), some lathyrogens (beta-aminopropionitrile and aminoacetonitrile) and other inhibitors (benzamide oxime, acetone oxime, hydroxylamine and pargyline). Tested by Ouchterlony's double diffusion in agarose gel, polyclonal antibodies against the amine oxidase from sainfoin, pea and grass pea cross-reacted with amine oxidases from several other Fabaceae and from barley (Hordeum vulgare) of Poaceae, while amine oxidase from the filamentous fungus Aspergillus niger did not cross-react at all. However, using Western blotting after SDS-PAGE with rabbit polyclonal antibodies against the amine oxidase from Aspergillus niger, some degree of similarity of plant amine oxidases from sainfoin, pea, field pea, grass pea, fenugreek, common melilot, white sweetclover and Vicia panonica with the A. niger amine oxidase was confirmed.

  11. Amine promoted, metal enhanced degradation of Mirex under high temperature conditions

    International Nuclear Information System (INIS)

    Jallad, Karim N.; Lynn, Bert C.; Alley, Earl G.

    2006-01-01

    In this study, zero-valent metal dehalogenation of mirex was conducted with amine solvents at high temperatures. Mirex was treated with excess amine in sealed glass tube reactors under nitrogen. The amines used were n-butyl amine (l), ethyl amine (l), dimethyl amine (g), diethyl amine (l), triethyl amine (l), trimethyl amine (g) and ammonia (g). The metals used were copper, zinc, magnesium, aluminum and calcium. The most suitable amine solvent and metal were selected by running a series of reactions with different amines and different zero-valent metals, in order to optimize the conditions under which complete degradation of mirex takes place. These dehalogenation reactions illustrated the role of zero-valent metals as reductants, whereas the amine solvents acted as proton donors. In this study, we report that mirex was completely degraded with diethyl amine (l) in the presence of copper at 100 deg. C and the hydrogenated products accounted for more than 94 of the degraded mirex

  12. New potential of the reductive alkylation of amines

    International Nuclear Information System (INIS)

    Gusak, K N; Ignatovich, Zh V; Koroleva, E V

    2015-01-01

    Available data on the reductive alkylation of amines with carbonyl compounds — a key method for the preparation of secondary and tertiary amines — are described systematically. The review provides information on the relevant reducing agents and catalysts and on the use of chiral catalysts in stereo- and enantiocontrolled reactions of amine synthesis. The effect of the reactant and catalyst structures on the reaction rates and chemo- and stereo(enantio)selectivity is considered. The bibliography includes 156 references

  13. Evaluation of amine inhibitors for suitability as crevice buffering agents

    International Nuclear Information System (INIS)

    Jayaweera, P.; Hettiarachchi, S.

    1994-03-01

    This report describes the results of a research effort to evaluate the suitability of some selected amines and amino acids as a crevice-buffering agents in pressurized water reactor (PWR) steam generators. The amines may be useful for buffering acid crevices, and the amino acids, because they contain both acidic and basic groups, may be useful for acidic and caustic crevices. Five commercially available amines and two amino acids were studied during this research. The study involved (1) the hydrolysis of these commercially available amines and amino acids, including measurement of their kinetics of decomposition, in simulated steam generator bulk water at 290 C, and (2) determination of their thermal stability in a simulated crevice environment. The study showed that, although the high-molecular-weight amines undergo hydrothermal decomposition, they have a better buffering capacity than their low-molecular-weight counterparts at 290 C. The amines provide effective crevice buffering by increasing the pH of the crevice solution by as much as 2.84 and to 4.24 units in the experimental setup used in this program. It was concluded that polyamines provide excellent buffering of the simulated crevice environment at 290 C and morpholine remains the best low-molecular-weight amine investigated. However, detailed volatility studies of the amines were not considered in this work. Such data would be needed before in-plant testing to ensure that the amines can concentrate in steam generator crevices to the levels assumed in this study

  14. Modular functionalization of allenes to aminated stereotriads.

    Science.gov (United States)

    Adams, Christopher S; Boralsky, Luke A; Guzei, Ilia A; Schomaker, Jennifer M

    2012-07-04

    Nitrogen-containing stereotriads, compounds with three adjacent stereodefined carbons, are commonly found in biologically important molecules. However, the preparation of molecules bearing these motifs can be challenging. Herein, we describe a modular oxidation protocol which converts a substituted allene to a triply functionalized amine of the form C-X/C-N/C-Y. The key step employs a Rh-catalyzed intramolecular conversion of the allene to a strained bicyclic methylene aziridine. This reactive intermediate is further elaborated to the target products, often in one reaction vessel and with effective transfer of the axial chirality of the allene to point chirality in the stereotriad.

  15. A One-Pot Selective Synthesis of N-Boc Protected Secondary Amines: Tandem Direct Reductive Amination/N-Boc Protection

    OpenAIRE

    Neelarapu, Raghupathi; Petukhov, Pavel A.

    2012-01-01

    A one-pot tandem direct reductive amination of aldehydes with primary amines resulting in N-Boc secondary amines using a (Boc)2O/sodium triacetoxyborohydride (STAB) system is reported. The tandem procedure is efficient, selective, and versatile, giving excellent yields of N-Boc protected secondary amines even in those cases where the products are prone to intramolecular lactamization

  16. A One-Pot Selective Synthesis of N-Boc Protected Secondary Amines: Tandem Direct Reductive Amination/N-Boc Protection.

    Science.gov (United States)

    Neelarapu, Raghupathi; Petukhov, Pavel A

    2012-09-02

    A one-pot tandem direct reductive amination of aldehydes with primary amines resulting in N-Boc secondary amines using a (Boc)(2)O/sodium triacetoxyborohydride (STAB) system is reported. The tandem procedure is efficient, selective, and versatile, giving excellent yields of N-Boc protected secondary amines even in those cases where the products are prone to intramolecular lactamization.

  17. Thermodynamics of organic mixtures containing amines

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Juan Antonio [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain)]. E-mail: jagl@termo.uva.es; Mozo, Ismael [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain); Fuente, Isaias Garcia de la [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain); Cobos, Jose Carlos [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain)

    2006-02-01

    Binary mixtures containing pyridine (PY), or 2-methylpyridine (2MPY) or 3-methylpyridine (3MPY) or 4-methylpyridine (4MPY) and an organic solvent as benzene, toluene, alkane, or 1-alkanol are investigated in the framework of DISQUAC. The corresponding interaction parameters are reported. The model describes accurately a whole set of thermodynamic properties: vapor-liquid equilibria (VLE), liquid-liquid equilibria (LLE), solid-liquid equilibria (SLE), molar excess Gibbs energies (G{sup E}), molar excess enthalpies (H{sup E}), molar excess heat capacities at constant pressure (C{sub P}{sup E}) and the concentration-concentration structure factor (S{sub CC}(0)). It is remarkable that DISQUAC correctly predicts the W-shaped curve of the C{sub P}{sup E} of the pyridine + n-hexadecane system. The model can be applied successfully to mixtures with strong positive or negative deviations from the Raoult's law. DISQUAC improves the theoretical results from UNIFAC (Dortmund version). The replacement of pyridine by a methylpyridine leads to a weakening of the amine-amine interactions, ascribed to the steric effect caused by the methyl group attached to the aromatic ring. This explains that for a given solvent (alkane, 1-alkanol) H{sup E}(pyridine)>H{sup E}(methylpyridine)

  18. Thermodynamics of organic mixtures containing amines

    International Nuclear Information System (INIS)

    Gonzalez, Juan Antonio; Mozo, Ismael; Fuente, Isaias Garcia de la; Cobos, Jose Carlos

    2006-01-01

    Binary mixtures containing pyridine (PY), or 2-methylpyridine (2MPY) or 3-methylpyridine (3MPY) or 4-methylpyridine (4MPY) and an organic solvent as benzene, toluene, alkane, or 1-alkanol are investigated in the framework of DISQUAC. The corresponding interaction parameters are reported. The model describes accurately a whole set of thermodynamic properties: vapor-liquid equilibria (VLE), liquid-liquid equilibria (LLE), solid-liquid equilibria (SLE), molar excess Gibbs energies (G E ), molar excess enthalpies (H E ), molar excess heat capacities at constant pressure (C P E ) and the concentration-concentration structure factor (S CC (0)). It is remarkable that DISQUAC correctly predicts the W-shaped curve of the C P E of the pyridine + n-hexadecane system. The model can be applied successfully to mixtures with strong positive or negative deviations from the Raoult's law. DISQUAC improves the theoretical results from UNIFAC (Dortmund version). The replacement of pyridine by a methylpyridine leads to a weakening of the amine-amine interactions, ascribed to the steric effect caused by the methyl group attached to the aromatic ring. This explains that for a given solvent (alkane, 1-alkanol) H E (pyridine)>H E (methylpyridine)

  19. Reducing tube bundle deposition with alternative amines

    International Nuclear Information System (INIS)

    Turner, C.W.; Klimas, S.J.; Frattini, P.L.

    1998-01-01

    Particle deposition rates have been measured in a high-temperature loop for magnetite and hematite depositing onto Inconel-600 under flow-boiling conditions with pH controlled using one of the following amines: morpholine, ammonia, ethanolamine, or dimethylamine. Hematite particles deposited at rates an order of magnitude greater than those measured for magnetite, although the hematite deposition rate dropped when the loop was operated under reducing conditions. The magnetite deposition rate was influenced by the amine used to control the pH, with the relative rate decreasing in the following series: morpholine (1) : ethanolamine (0.72) ammonia (0.51) : dimethylamine (0.25). These trends in deposition rate are discussed in terms of the surface chemistry of the corrosion products. Deposition rates for both magnetite and hematite increased significantly once the mixture quality exceeded about 0.3, which may be related to a change in the heat transfer mechanism from nucleate boiling to two-phase forced convection through a thin film. (author)

  20. Amine-functionalized magnetic nanoparticles as robust support for ...

    Indian Academy of Sciences (India)

    and 2,2 -(ethylenedioxy)bis(ethylamine) (EDBE) as amine precursors. These aminated nanoparticles were used as support for the immobilization of lipase, an important industrial enzyme. Lipase was immobilized via glutaraldehyde coupling agent. These functionalized nanoparticles were characterized by XRD, FTIR, TEM,.

  1. Efficient acetylation of primary amines and amino acids in ...

    Indian Academy of Sciences (India)

    The present methodology illustrates the efficient acetylation of primary amines and amino acids in brine solution by means of acetyl chloride under weakly basic condition in the presence of sodium acetate and/or triethyl amine followed by trituration with aqueous saturated bicarbonate solution. This effort represents the first ...

  2. Linear free energy relationship in reactions between diphenyl amine ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 118; Issue 3. Linear free energy relationship in reactions between diphenyl amine and benzyl bromides. S Ranga Reddy P Manikyamba. Volume ... Keywords. Diphenyl amine; substituent effect; reaction constant; isokinetic temperature; linear free energy relationship.

  3. Conditions allowing the formation of biogenic amines in cheese

    NARCIS (Netherlands)

    Joosten, H.M.L.J.

    1988-01-01

    A study was undertaken to reveal the conditions that allow the formation of biogenic amines in cheese.

    The starters most commonly used in the Dutch cheese industry do not have decarboxylative properties. Only if the milk or curd is contaminated with non-starter bacteria, amine

  4. Amine-functionalized magnetic nanoparticles as robust support for ...

    Indian Academy of Sciences (India)

    surface were prepared through solvothermal method, using poly(ethylene imine) (PEI), ethanolamine (EA), and 2,2 -(ethylenedioxy)bis(ethylamine) (EDBE) as amine precursors. These aminated nanoparticles were used as support for the immobilization of lipase, an important industrial enzyme. Lipase was immobilized via.

  5. Predicting the phospholipophilicity of monoprotic positively charged amines

    NARCIS (Netherlands)

    Droge, S T J; Hermens, J L M; Gutsell, S; Rabone, J; Hodges, G

    2017-01-01

    The sorption affinity of eighty-six charged amine structures to phospholipid monolayers (log KIAM) was determined using immobilized artificial membrane high-performance liquid chromatography (IAM-HPLC). The amine compounds covered the most prevalent types of polar groups, widely ranged in structural

  6. Diesel fuel containing polyalkylene amine and Mannich base

    Energy Technology Data Exchange (ETDEWEB)

    Harle, O.L.

    1979-09-04

    Disclosed is a fuel additive and fuel composition. The additive comprises a mixture of a polyalkylene amine and the reaction product of an alkylphenol, an aldehyde and an amine. The additive provides surprising stability in preventing thermal degradation of fuels, particularly fuels for compression ignition engines.

  7. Biogenic amines degradation by microorganisms isolated from cheese

    Directory of Open Access Journals (Sweden)

    Irena Butor

    2017-01-01

    Full Text Available The aim of this study was the isolation and characterization of microorganisms able to degrade biogenic amines and their identification. Individual microorganisms were obtained by isolation from commercially available foodstuffs and food produced in the technological laboratories of Faculty of Technology, Tomas Bata University in Zlín and subsequently identified by MALDI-TOF MS. The results of MALDI-TOF MS identification were verified by 16S rRNA sequenation. In this work was studied the ability of 5 bacterial strains positive to biogenic amines degradation isolated from dairy products to decrease biogenic amines content in vitro and quantified reduction in the concentration of biogenic amines tryptamine, β-phenylethylamine, putrescine, cadaverine, histamine and tyramine. The level of degradation (decrease of biogenic amines was determined on the base of the ability to grow in media with biogenic amines as the sole source carbon and nitrogen. The isolated strains with the ability of degradation of one or more biogenic amines were cultured in medium supplemented with relevant biogenic amines, the media derivatized with dansyl chloride and these amines separated by HPLC at a wavelength of 254 nm. From five tested strains identified as Bacillus subtilis, Bacillus pumilus, Enterobacter cloacae, Rhizobium radiobacter and Acinetobacter pitii, isolated from gouda type cheese, the greatest ability of degradation was observed in Bacillus subtilis, which was capable to degrade almost all amount of histamine, cadaverine and putrescine. Other four strains showed a lower rate of degradation than Bacillus subtilis, but the ability to degrade biogenic amines with these microorganisms was still significant.

  8. Heterocyclic amines produced in cooked food: unavoidable xenobiotics.

    Science.gov (United States)

    Sugimura, T; Wakabayashi, K; Ohgaki, H; Takayama, S; Nagao, M; Esumi, H

    1990-01-01

    Humans are continuously exposed to naturally occurring and industrial xenobiotics in their daily lives. Heterocyclic amines, which are formed during the cooking of proteinaceous foods, have been categorized as a new class of naturally occurring xenobiotics. They are divided into 2-amino-3-methylimidazo[4,5-f] quinoline (IQ)- and non-IQ-types. The amounts and proportion of total mutagenicity contributed by the IQ-type heterocyclic amines in cooked food are greater than those of the non-IQ-types. Precursors of the IQ-type heterocyclic amines including IQ, 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) are creatinine, amino acids and sugars in meat and fish. Both types of heterocyclic amines are carcinogenic in mice and rats. All heterocyclic amines except PhIP frequently induce cancers in the liver, while PhIP induces lymphomas in mice and carcinomas of the colon and mammary gland in rats. Based on quantitative analysis of heterocyclic amines in cooked food and levels of excretion of unchanged heterocyclic amines in human urine, total heterocyclic amine intake was calculated to be around 0.4-16 micrograms/person per day. As in the case of other naturally occurring xenobiotics, and degree of exposure is small and is presumably insufficient alone to account for the development of human cancer. Nevertheless, a linear relationship has been demonstrated between DNA adduct levels and a wide range of doses of MeIQx in animals. In addition, combined treatment with five heterocyclic amines yielded additive or synergistic effects in the development of glutathione S-transferase placental form (GST-P) positive foci. Taking these results and current observations of multiple genetic alterations in human cancers into consideration together, heterocyclic amines are probably involved in the development of human cancer in the presence of other carcinogens, tumor promoters and factors stimulating cancer progression.

  9. Phenomenological and analytical interpretation of the rain-deposit relationship used for the reconstitution of the cesium 137 deposit in France consecutive to the accident of Chernobylsk; Interpretation phenomenologique et analytique de la relation pluie-depot utilisee pour la reconstitution des depots de {sup 137}Cs en France consecutifs a l'accident de Tchernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Champion, D.; Renaud, Ph.; Metivier, J.M.; Garcia-Sanchez, L.; Pourcelot, L. [Institut de Radioprotection et de Surete Nucleaire, Dir. de l' environnement et de l' intervention 92 - Fontenay-aux-Roses (France)

    2005-11-15

    The works presented in this report allow to give two conclusions: the first one bears on the reconstitution of the cesium 137 deposits induced by the Chernobylsk accident; the second one bears on the methods improvement of post accident consequences evaluation induced by the radioactive atmosphere fallout. (N.C.)

  10. Remedial radiotherapy for an isolated biochemical relapse after prostatectomy: impact of the PSA doubling time and of the global response, whichever definition of the relapse is used; Radiotherapie de rattrapage pour une recidive biochimique isolee apres prostatectomie: impact du temps de doublement du PSA et de la reponse complete, quelle que soit la definition de recidive utilisee

    Energy Technology Data Exchange (ETDEWEB)

    Martin, E.; Crehange, G.; Gauthier, M.; Bosset, M.; Maingon, P. [Centre Georges Francois Leclerc, 21 - Dijon (France); Martin, E.; Carrie, C.; Pommier, P. [Centre Leon-Berard, 69 - Lyon (France); Bosset, J.F. [Hopital Jean-Minjoz, 25 - Besancon (France)

    2010-10-15

    The authors report a study aimed at identifying relapse predictive factors after a remedial radiotherapy for prostatic adenocarcinomas in isolated biochemical relapse after prostatectomy among a selected population. Based on data obtained on 97 patients treated between 1995 and 2005 by conformational irradiation, and on different definitions of biochemical relapse, the authors conclude that PSA serum concentration doubling time and getting a complete response are independent relapse prognostic factors. These factors are the same whichever definition of relapse is used. Short communication

  11. Bioreducible poly(amido amine)s with oligoamine side chains: synthesis, characterization, and structural effects on gene delivery

    NARCIS (Netherlands)

    Lin, C.; Blaauboer, Cees-Jan; Mateos timoneda, Miguel; Lok, Martin C.; Steenbergen, Mies; Hennink, Wim E.; Zhong, Zhiyuan; Feijen, Jan; Engbersen, Johannes F.J.

    2008-01-01

    A group of bioreducible poly(amido amine)s containing multiple disulfide linkages in main chain and oligoamines in side chain (SS–PAOAs) were prepared by Michael-type polyaddition of N-tert-butyloxycarbonyl (N-Boc) protected oligoamine to the disulfide-containing cystaminebisacrylamide, followed by

  12. Production of Primary Amines by Reductive Amination of Biomass-Derived Aldehydes/Ketones.

    Science.gov (United States)

    Liang, Guanfeng; Wang, Aiqin; Li, Lin; Xu, Gang; Yan, Ning; Zhang, Tao

    2017-03-06

    Transformation of biomass into valuable nitrogen-containing compounds is highly desired, yet limited success has been achieved. Here we report an efficient catalyst system, partially reduced Ru/ZrO 2 , which could catalyze the reductive amination of a variety of biomass-derived aldehydes/ketones in aqueous ammonia. With this approach, a spectrum of renewable primary amines was produced in good to excellent yields. Moreover, we have demonstrated a two-step approach for production of ethanolamine, a large-market nitrogen-containing chemical, from lignocellulose in an overall yield of 10 %. Extensive characterizations showed that Ru/ZrO 2 -containing multivalence Ru association species worked as a bifunctional catalyst, with RuO 2 as acidic promoter to facilitate the activation of carbonyl groups and Ru as active sites for the subsequent imine hydrogenation. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Synthesis and characterization of bisimide amines and bisimide amine-cured epoxy resins

    Science.gov (United States)

    Scola, D. A.

    1983-01-01

    An attempt is made to develop tough, moisture resistant, high char yield epoxy resins by means of novel bisimide amine (BIA) hardener curing agents and a state-of-the-art epoxy resin system. The BIAs are isolated as mixtures containing monomer, oligomer, and polymeric species, and then characterized by elemental analysis and high pressure liquid chromatography. The bisimide amine-cured epoxies (IMEs) were characterized with respect to moisture absorption, thermal properties, and physical and mechanical properties, as well as in the role of matrices in Celion 6000/IME composites. The relative toughness characteristics of each IME formulation was measured by the 10 deg off-axis tensile test, measuring the uniaxial tensile strength, shear strength, and shear-strain-to-failure of the composite systems.

  14. Electrochemical characterization of aminated acrylic conducting polymer

    International Nuclear Information System (INIS)

    Rashid, Norma Mohammad; Heng, Lee Yook; Ling, Tan Ling

    2015-01-01

    New attempt has been made to synthesize aminated acrylic conducting polymer (AACP) using precursor of phenylvinylsulfoxide (PVS). The process was conducted via the integration of microemulsion and photopolymerization techniques. It has been utilized for covalent immobilization of amino groups by the adding of N-achryiloxisuccinimide (NAS). Thermal eliminating of benzene sulfenic acids from PVS has been done at 250 °C to form electroactive polyacetylene (PA) segment. Characterization of AACP has been conducted using fourier transform infrared (FTIR), scanning electron microscopy (SEM) and linear sweep cyclic voltammetry (CV). A range of 0.3-1.25μm particle size obtained from SEM characterization. A quasi-reversible system performed as shown in electrochemical study

  15. Whole cell biotransformation for reductive amination reactions

    Science.gov (United States)

    Klatte, Stephanie; Lorenz, Elisabeth; Wendisch, Volker F

    2014-01-01

    Whole cell biotransformation systems with enzyme cascading increasingly find application in biocatalysis to complement or replace established chemical synthetic routes for production of, e.g., fine chemicals. Recently, we established an Escherichia coli whole cell biotransformation system for reductive amination by coupling a transaminase and an amino acid dehydrogenase with glucose catabolism for cofactor recycling. Transformation of 2-keto-3-methylvalerate to l-isoleucine by E. coli cells was improved by genetic engineering of glucose metabolism for improved cofactor regeneration. Here, we compare this system with different strategies for cofactor regeneration such as cascading with alcohol dehydrogenases, with alternative production hosts such as Pseudomonas species or Corynebacterium glutamicum, and with improving whole cell biotransformation systems by metabolic engineering of NADPH regeneration. PMID:24406456

  16. Biogenic amines in Portuguese traditional foods and wines.

    Science.gov (United States)

    Ferreira, Isabel M P L V O; Pinho, Olívia

    2006-09-01

    The presence of biogenic amines in foodstuffs is an important food safety problem because of the implication of these compounds in food intolerance and intoxication. The separation and quantification of biogenic amines in foods is normally performed by chromatographic techniques. This review contains descriptions of the quantification of biogenic amines in Portuguese traditional fermented and/or ripened foods and wines, including Protected Denomination of Origin cheeses, dry-cured sausages, and Portuguese wines (including Port wines), using different analytical methods based on high-pressure liquid chromatography (UV or diode array and/or fluorometric detectors) and gas chromatography (with a mass spectrometry detector). The evolution of biogenic amines during fermentation, ripening, aging, or storage of those products was also evaluated. Biogenic amine concentrations ranged widely within individual food items, and storage, transport, and handling conditions can influence to some extent the biogenic amines present and their concentrations. Traditional foods are an important part of the Portuguese diet, and a high intake of harmful amounts of biogenic amines from traditional Portuguese fermented foods is possible. However, extensive research is needed to extend the current limited database.

  17. IED Afrique, notre histoire pour le meilleur...

    International Development Research Centre (IDRC) Digital Library (Canada)

    IDRC CRDI

    De même, notre Conseil d'Administration peine à se mobiliser au service de la structure du fait de la spécificité ... crucial pour une organisation qui n'arrive pas à mobiliser des ressources suffisantes qui lui permettraient de ... La communication pour augmenter la notoriété et la visibilité de l'organisation auprès notamment ...

  18. Apport maternel chez la balane tropicale : Plasticite de l'allocation de la ressource trophique pour la production larvaire en conditions de limitation nutritionnelle et de stress environnemental

    Science.gov (United States)

    Freuchet, Florian

    Dans le milieu marin, l'abondance du recrutement depend des processus qui vont affecter les adultes et le stock de larves. Sous l'influence de signaux fiables de la qualite de l'habitat, la mere peut augmenter (effet maternel anticipatoire, 'anticipatory mother effects', AME) ou reduire (effet maternel egoiste, 'selfish maternai effects', SME) la condition physiologique de la progeniture. Dans les zones tropicales, generalement plus oligotrophes, la ressource nutritive et la temperature sont deux composantes importantes pouvant limiter le recrutement. Les effets de l'apport nutritionnel et du stress thermique sur la production de larves et sur la stategie maternelle adoptee ont ete testes dans cette etude. Nous avons cible la balane Chthamalus bisinuatus (Pilsbry) comme modele biologique car el1e domine les zones intertidales superieures le long des cotes rocheuses du Sud-Est du Bresil (region tropicale). Les hypotheses de depart stipulaient que l'apport nutritionnel permet aux adultes de produire des larves de qualite elevee et que le stress thermique genere une ponte precoce, produisant des larves de faible qualite. Afin de tester ces hypotheses, des populations de C. bisinuatus ont ete elevees selon quatre groupes experimentaux differents, en combinant des niveaux d'apport nutritionnel (eleve et faible) et de stress thermique (stresse et non stresse). Des mesures de survie et de conditions physiologiques des adultes et des larves ont permis d'identifier les reponses parentales pouvant etre avantageuses dans un environnement tropical hostile. L'analyse des profils en acides gras a ete la methode utilisee pour evaluer la qualite physiologique des adultes et de larves. Les resultats du traitement alimentaire (fort ou faible apport nutritif), ne montrent aucune difference dans l'accumulation de lipides neutres, la taille des nauplii, l'effort de reproduction ou le temps de survie des nauplii en condition de jeune. Il semble que la faible ressource nutritive est

  19. Amine functionalized nanodiamond promotes cellular adhesion, proliferation and neurite outgrowth

    International Nuclear Information System (INIS)

    Hopper, A P; Dugan, J M; Gill, A A; Haycock, J W; Claeyssens, F; Fox, O J L; May, P W

    2014-01-01

    In this study, we report the production of amine functionalized nanodiamond. The amine functionalized nanodiamond forms a conformal monolayer on a negatively charged surface produced via plasma polymerization of acrylic acid. Nanodiamond terminated surfaces were studied as substrates for neuronal cell culture. NG108-15 neuroblastoma-glyoma hybrid cells were successfully cultured upon amine functionalized nanodiamond coated surfaces for between 1 and 7 d. Additionally, primary dorsal root ganglion (DRG) neurons and Schwann cells isolated from Wistar rats were also successfully cultured over a period of 21 d illustrating the potential of the coating for applications in the treatment of peripheral nerve injury. (paper)

  20. Developpement d'un catalyseur nickel-alumine efficace pour le reformage de diesel a la vapeur d'eau et etude du systeme reactionnel

    Science.gov (United States)

    Fauteux-Lefebvre, Clemence

    Le developpement de sources d'energie alternatives fiables et efficaces est aujourd'hui une necessite. L' interet dans le reformage d'hydrocarbures liquides est ainsi croissant puisqu'il s'agit d'une voie pour l'alimentation des piles a combustible. Les piles a combustible ont une efficacite pour la conversion d'energie en electricite plus grande que celle des moteurs a combustion et font ainsi partie de la recherche de solution en efficacite energetique. Ces piles consomment de l'hydrogene comme combustible pour produire de l'electricite, d'ou l'interet pour le reformage. En effet, cette reaction permet de produire de l'hydrogene et du monoxyde de carbone (un autre combustible des piles a combustible a electrolyte solide) a partir d'hydrocarbure liquide, notamment le diesel. Les piles pourraient donc etre integrees avec une unite de reformage leur fournissant directement le combustible necessaire a partir de diesel. Dans ce projet de recherche, un nouveau catalyseur de nickel sous forme de spinelle nickel-alumine (spinelle NiAl2O4 sur support d'alumine et de zircone stabilisee avec yttria) a ete developpe et teste en laboratoire pour du reformage de propane, d'hydrocarbures liquides et de diesel, a la vapeur d'eau. Par ailleurs, une methode d'ajout des reactifs novatrice a ete utilisee afin de diminuer la pyrolyse precedant le reformage, en utilisant une emulsion. Les resultats de reformage d'hydrocarbures purs ont montre des concentrations tres pres de l'equilibre thermodynamique et une activite constante sans desactivation du catalyseur ni formation de carbone, et ce avec des ratios H2O/C de moins de 2.5 et des temperatures d'operation variant entre 630 °C et 750 °C. Lors de tests effectues en utilisant du diesel fossile, a 705°C, avec un debit volumique des reactifs de plus de 50 000 cm3gcat-1h-1 et un ratio H2O/C de moins de 2.5, l'activite a ete maintenue pendant plus de 15 heures, malgre une operation en cycles. L'analyse du catalyseur apres cette

  1. Extraction separation studies of uranium(VI) by amine oxides

    International Nuclear Information System (INIS)

    Ejaz, M.

    1975-01-01

    The extraction of uranium(VI) by two amine oxides, 4-(5-nonyl)pyridine oxide and trioctylamine oxide has been studied. The extraction behavior of these two N-oxides is compared. The dependence of extraction on the type of amine oxide and acid, nature of organic diluent, and amine oxide concentration has been investigated. The influence of the concentration of the metal and salting-out agents is described. The possible mechanism of extraction is discussed in the light of the results of extraction isotherms, loading radiodata, and log-log plots of amine oxide concentration vs distribution ratio. The separation factors for a number of metal ions are reported, and the separation of uranium from some fission elements has also been achieved

  2. Next Generation Life Support (NGLS): Rapid Cycle Amine Swing Bed

    Data.gov (United States)

    National Aeronautics and Space Administration — The Rapid Cycle Amine (RCA) swingbed has been identified as a technology with high potential to meet the stringent requirements for the next generation spacesuit's...

  3. Amine reclaiming technologies in post-combustion carbon dioxide capture.

    Science.gov (United States)

    Wang, Tielin; Hovland, Jon; Jens, Klaus J

    2015-01-01

    Amine scrubbing is the most developed technology for carbon dioxide (CO2) capture. Degradation of amine solvents due to the presence of high levels of oxygen and other impurities in flue gas causes increasing costs and deterioration in long term performance, and therefore purification of the solvents is needed to overcome these problems. This review presents the reclaiming of amine solvents used for post combustion CO2 capture (PCC). Thermal reclaiming, ion exchange, and electrodialysis, although principally developed for sour gas sweetening, have also been tested for CO2 capture from flue gas. The three technologies all have their strengths and weaknesses, and further development is needed to reduce energy usage and costs. An expected future trend for amine reclamation is to focus on process integration of the current reclaiming technologies into the PCC process in order to drive down costs. Copyright © 2014. Published by Elsevier B.V.

  4. Zinc catalyzed Guanylation reaction of Amines with Carbodiimides ...

    Indian Academy of Sciences (India)

    016-1096-y. Zinc catalyzed Guanylation reaction of Amines with Carbodiimides/. Isocyanate leading to Guanidines/Urea derivatives formation. JAYEETA BHATTACHARJEE, MITALI SACHDEVA, INDRANI BANERJEE and. TARUN K PANDA.

  5. Two simple amine hydrochlorides from the soft coral Lobophytum strictum

    Digital Repository Service at National Institute of Oceanography (India)

    Parameswaran, P.S.; Naik, C.G.; Das, B.; Kamat

    Two simple amine hydrochlorides, viz., 1-amino-1, 1-dimethyl-3-oxo-butane hydrochloride (1) (Diacetonamine) and 2, 2, 6, 6-tetramethylpiperidone hydrochloride (2) have been isolated from the fraction of the methanolic extract of the soft coral...

  6. Health Problems of Epoxy Resins and Amine-curing Agents

    Science.gov (United States)

    Bourne, L. B.; Milner, F. J. M.; Alberman, K. B.

    1959-01-01

    Epoxy resins were first introduced about 10 years ago. Toxic effects, particularly dermatitis, have been frequently described. An investigation into the possible causes of pathological sequelae following the use of epoxy resin/amine mixtures has been undertaken. The cause of most cases of dermatitis and sensitization appears to be uncombined amine which is present in recent mixtures and persists in hardened resin for long periods. The results of experiments with two of the most commonly used resin/amine mixtures confirm this. Cold-cured resins are more dangerous and remain so even when hardened. A simple theory is suggested for the mechanism of the reaction between epoxy resins, amines, and biological systems. This theory leads logically to the handling precautions outlined. Images PMID:13651551

  7. Silver-catalyzed synthesis of amides from amines and aldehydes

    Science.gov (United States)

    Madix, Robert J; Zhou, Ling; Xu, Bingjun; Friend, Cynthia M; Freyschlag, Cassandra G

    2014-11-18

    The invention provides a method for producing amides via the reaction of aldehydes and amines with oxygen adsorbed on a metallic silver or silver alloy catalyst. An exemplary reaction is shown in Scheme 1: (I), (II), (III). ##STR00001##

  8. Calcium(ii)-catalyzed enantioselective conjugate additions of amines.

    Science.gov (United States)

    Uno, Brice E; Dicken, Rachel D; Redfern, Louis R; Stern, Charlotte M; Krzywicki, Greg G; Scheidt, Karl A

    2018-02-14

    The direct enantioselective chiral calcium(ii)·phosphate complex (Ca[CPA] 2 )-catalyzed conjugate addition of unprotected alkyl amines to maleimides was developed. This mild catalytic system represents a significant advance towards the general convergent asymmetric amination of α,β-unsaturated electrophiles, providing medicinally relevant chiral aminosuccinimide products in high yields and enantioselectivities. Furthermore, the catalyst can be reused directly from a previously chromatographed reaction and still maintain both high yield and selectivity.

  9. Catalyst Deactivation Reactions : The Role of Tertiary Amines Revisited

    NARCIS (Netherlands)

    Novarino, Elena; Rios, Itzel Guerrero; van der Veer, Siebe; Meetsma, Auke; Hessen, Bart; Bouwkamp, Marco W.

    2011-01-01

    Decamethylzirconocene cation [Cp*2ZrMe](+) (2) decomposes in bromobenzene-d(5) solution to generate sigma-aryl species [Cp*Zr-2(2-C6H4Br-kappa Br,C)][B(C6F5)(4)] (3). This a-bond metathesis reaction is catalyzed by tertiary amines via a two-step mechanism, in which the amine acts as a proton relay.

  10. Facile and Green Synthesis of Saturated Cyclic Amines.

    Science.gov (United States)

    Hameed, Arruje; Javed, Sadia; Noreen, Razia; Huma, Tayyaba; Iqbal, Sarosh; Umbreen, Huma; Gulzar, Tahsin; Farooq, Tahir

    2017-10-12

    Single-nitrogen containing saturated cyclic amines are an important part of both natural and synthetic bioactive compounds. A number of methodologies have been developed for the synthesis of aziridines, azetidines, pyrrolidines, piperidines, azepanes and azocanes. This review highlights some facile and green synthetic routes for the synthesis of unsubstituted, multisubstituted and highly functionalized saturated cyclic amines including one-pot, microwave assisted, metal-free, solvent-free and in aqueous media.

  11. Facile and Green Synthesis of Saturated Cyclic Amines

    Directory of Open Access Journals (Sweden)

    Arruje Hameed

    2017-10-01

    Full Text Available Single-nitrogen containing saturated cyclic amines are an important part of both natural and synthetic bioactive compounds. A number of methodologies have been developed for the synthesis of aziridines, azetidines, pyrrolidines, piperidines, azepanes and azocanes. This review highlights some facile and green synthetic routes for the synthesis of unsubstituted, multisubstituted and highly functionalized saturated cyclic amines including one-pot, microwave assisted, metal-free, solvent-free and in aqueous media.

  12. Dispersant additives derived from lactone modified amido-amine adducts

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez, A.; Lundberg, R.D.

    1990-10-16

    This patent describes a lactone modified dispersant additive. It comprises one adduct of a polyolefin of 300 to 10,000 number average molecular weight substituted with at least 0.8 (e.g., from about 1 to 4) dicarboxylic acid producing moieties (preferably acid or anhydride moieties) per polyolefin molecule, an amido-amine or thioamido-amine characterized by being a reaction product of at least a polyamine and an alpha, beta-unsaturated compound.

  13. Diesel fuel containing polyalkylene amine and Mannich base

    Energy Technology Data Exchange (ETDEWEB)

    Harle, O.L.

    1979-06-21

    The fuel composition for diesel engines is characterized in that it contains a hydrocarbon with a boiling range of 120-455/sup 0/C as main component and as additive 5 to 300 ppm of a polyakylene amine, as well as 5 to 300 ppm of the reaction product of an alkyl phenol, an aldehyde and an amine (Mannich base). This additive composition increases the oxidation and thermal stability of the fuel.

  14. Decoding nitric oxide release rates of amine-based diazeniumdiolates.

    Science.gov (United States)

    Wang, Yan-Ni; Collins, Jack; Holland, Ryan J; Keefer, Larry K; Ivanic, Joseph

    2013-08-01

    Amine-based diazeniumdiolates (NONOates) have garnered widespread use as nitric oxide (NO) donors, and their potential for nitroxyl (HNO) release has more recently been realized. While NO release rates can vary significantly with the type of amine, half-lives of seconds to days under physiological conditions, there is as yet no way to determine a priori the NO or HNO production rates of a given species, and no discernible trends have manifested other than that secondary amines produce only NO (i.e., no HNO). As a step to understanding these complex systems, here we describe a procedure for modeling amine-based NONOates in water solvent that provides an excellent correlation (R(2) = 0.94) between experimentally measured dissociation rates of seven secondary amine species and their computed NO release activation energies. The significant difference in behavior of NONOates in the gas and solvent phases is also rigorously demonstrated via explicit additions of quantum mechanical water molecules. The presented results suggest that the as-yet unsynthesized simplest amine-based NONOate, the diazeniumdiolated ammonia anion [H2N-N(O)═NO(-)], could serve as an unperturbed HNO donor. These results provide a step forward toward the accurate modeling of general NO and/or HNO donors as well as for the identification of tailored prodrug candidates.

  15. Brain perfusion imaging with iodinated amines

    International Nuclear Information System (INIS)

    Kung, H.F.

    1989-01-01

    Traditional nuclear medicine brain study using 99m Tc pertechnetate, glucoheptonate or diethlenetriaminepentacetic acid (DTPA) and planar imaging has experienced a significant decline in the past 10 years. This is mainly due to the introduction of X-ray CT and more recently the nuclear magnetic resonance (NMR) imaging, by which detailed morphology of the brain, including the detection of breakdown of the blood-brain barrier, can be obtained. The nuclear medicine brain imaging is only prescribed as a complementary test when X-ray CT is negative or equivocal and clinical suspicion remains. The attention of nuclear medicine brain imaging has been shifted from the detection of the breakdown of the blood-brain barrier to the study of brain function-perfusion, metabolism, and receptor binding, etc. The functional brain imaging provides diagnostic information usually unattainable by other radiological techniques. In this article, the iodinated amines as brain perfusion imaging agents are reviewed. Potential clinical application of these agents is discussed

  16. Development of I-123-labeled amines for brain studies: localization of I-123 iodophenylalkyl amines in rat brain

    International Nuclear Information System (INIS)

    Winchell, H.S.; Baldwin, R.M.; Lin, T.H.

    1980-01-01

    Localization in rat brain of forty iodophenylalkyl amines labeled with I-123 was evaluated in an attempt to develop I-123-labeled amines useful for brain studies. For the amines studied, the highest activity in brain and the brain-to-blood activity ratios ranked p > m > o as related to iodine position on the benzene ring: for alkyl groups the rank order was α-methylethyl > ethyl > methyl > none; for N additions it was single lipophilic group > H > two lipophilic groups. It is suggested that introduction of a halogen into the ring structure of many amines results in greater concentration of the agent in brain than is seen with the nonhalogenated parent compound. The agent N-isopropyl-p-iodoamphetamine was chosen for further study because, in the rat, it showed high brain activity (1.57%/g) and brain-blood ratio (12.6) at 5 min

  17. Approches pour la reduction de l'impact de defaut dans le transport d'energie du parc eolien offshore via VSC-HVDC =

    Science.gov (United States)

    Benadja, Mounir

    Dans ce travail est presente un systeme de generation d'energie d'un parc eolien offshore et un systeme de transport utilisant les stations VSC-HVDC connectees au reseau principal AC onshore. Trois configurations ont ete etudiees, modelisees et validees par simulation. Dans chacune des configurations, des contributions ameliorant les cotes techniques et economiques sont decrites ci-dessous : La premiere contribution concerne un nouvel algorithme MPPT (Maximum Power Point Tracking) utilise pour l'extraction de la puissance maximale disponible dans les eoliennes des parcs offshores. Cette technique d'extraction du MPPT ameliore le rendement energetique de la chaine de conversion des energies renouvelables notamment l'energie eolienne a petite et a grande echelles (parc eolien offshore) qui constitue un probleme pour les constructeurs qui se trouvent confrontes a developper des dispositifs MPPT simples, moins couteux, robustes, fiables et capable d'obtenir un rendement energetique maximal. La deuxieme contribution concerne la reduction de la taille, du cout et de l'impact des defauts electriques (AC et DC) dans le systeme construit pour transporter l'energie d'un parc eolien offshore (OWF) vers le reseau principal AC onshore via deux stations 3L-NPC VSCHVDC. La solution developpee utilise des observateurs non-lineaires bases sur le filtre de Kalman etendu (EKF). Ce filtre permet d'estimer la vitesse de rotation et la position du rotor de chacune des generatrices du parc eolien offshore et de la tension du bus DC de l'onduleur DC-AC offshore et des deux stations 3L-NPC-VSC-HVDC (offshore et onshore). De plus, ce developpement du filtre de Kalman etendu a permis de reduire l'impact des defauts AC et DC. Deux commandes ont ete utilisees, l'une (commande indirect dans le plan abc) avec EKF integre destinee pour controler le convertisseur DC-AC offshore et l'autre (commande d-q) avec EKF integre pour controler les convertisseurs des deux stations AC-DC et DC-AC tout en

  18. Synthesis of N-Boc-Propargylic and Allylic Amines by Reaction of Organomagnesium Reagents with N-Boc-Aminals and Their Oxidation to N-Boc-Ketimines.

    Science.gov (United States)

    Kano, Taichi; Kobayashi, Ryohei; Maruoka, Keiji

    2016-01-15

    Previously inaccessible N-Boc-protected propargylic and allylic amines were synthesized by the reaction between N-Boc-aminals and organomagnesium reagents through the in situ generated N-Boc-imine intermediates. The obtained N-Boc-propargylic amines could be readily converted into unprecedented N-Boc-ketimines by oxidation with manganese dioxide.

  19. Catalytic Ester and Amide to Amine Interconversion: Nickel-Catalyzed Decarbonylative Amination of Esters and Amides by C−O and C−C Bond Activation

    KAUST Repository

    Yue, Huifeng

    2017-03-15

    An efficient nickel-catalyzed decarbonylative amination reaction of aryl and heteroaryl esters has been achieved for the first time. The new amination protocol allows the direct interconversion of esters and amides into the corresponding amines and represents a good alternative to classical rearrangements as well as cross coupling reactions.

  20. Complexation des acides aminés basiques arginine, histidine et lysine avec l'ADN plasmidique en solution aqueuse : participation à la capture de radicaux sous irradiation X à 1,5 keV

    Science.gov (United States)

    Tariq Khalil, Talat; Taillefumier, Baptiste; Boulanouar, Omar; Mavon, Christophe; Fromm, Michel

    2016-09-01

    L'environnement chimique de l'ADN en situation biologique est complexe notam-ment en raison de la présence d'histones, protéines nucléaires, associées en quantité approximativement égales à l'ADN pour former la chromatine. Les histones possèdent de nombreux radicaux basiques arginine et lysine chargés positivement et dont la majorité se trouve sur les chaînes émergentes, l'ADN présente quant à lui des charges négatives sur ses groupements phosphates localisés tout au long de la double hélice. Dans cette étude, la complexité de la structure de la chromatine nucléaire est dans un premier temps mimée en solution aqueuse par la formation de complexes entre un ADN plasmidique sonde et les trois acides aminés basiques, Arg, His, Lys, qui, mis à part His, sont protonés au pH physiologique. Ces acides aminés libres en solution sont réputés être des capteurs efficaces de radicaux libres, notamment pour le radical hydroxyle, conférant ainsi un pouvoir protecteur vis-à-vis des effets indirects sur l'ADN en situation d'exposition aux rayonnements ionisants. A concentration fixée, les capacités de capture des acides aminés libres, σ, pour le radical hydroxyle sont typiquement les suivantes σHis ≈σArg > σLys (σLys ≈ 0,1 × σArg). Nous avons mesuré les taux de cassures simple brin par plasmide et par Gray (χ) lors d'expositions de solutions aqueuses de complexes [acide aminé - ADN plasmidique] aux rayons X ultra-mous (1,5 keV). A concentrations égales, les trois acides aminés complexés et présents en large excès ne manifestent pas une capacité de protection de l'ADN proportionnelle à leur capacité de capture libre et en solution ; on trouve en effet des taux de cassures dans l'ordre suivant χHis > χArg > χLys (χLys ≈ 0,01 χArg). Après avoir détaillé le mode opératoire de ces mesures, nous analyserons sur des bases bibliographiques, les modes spécifiques d'interaction des acides aminés basiques avec l'ADN. La sp

  1. Guides et formulaires | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Demande de subvention de recherche du CRDI · Budget de proposition · Lignes directrices du CRDI pour la préparation du rapport d'étape technique · Lignes directrices du CRDI pour la préparation du rapport technique final · Lignes directrices du CRDI pour les dépenses de projet admissibles · Lignes directrices pour la ...

  2. Determination of rate constants of N-alkylation of primary amines by 1H NMR spectroscopy.

    Science.gov (United States)

    Li, Chenghong

    2013-09-05

    Macromolecules containing N-diazeniumdiolates of secondary amines are proposed scaffolds for controlled nitrogen oxide (NO) release medical applications. Preparation of these compounds often involves converting primary amine groups to secondary amine groups through N-alkylation. However, N-alkylation results in not only secondary amines but tertiary amines as well. Only N-diazeniumdiolates of secondary amines are suitable for controlled NO release; therefore, the yield of secondary amines is crucial to the total NO load of the carrier. In this paper, (1)H NMR spectroscopy was used to estimate the rate constants for formation of secondary amine (k1) and tertiary amine (k2) for alkylation reagents such as propylene oxide (PO), methyl acrylate (MA), and acrylonitrile (ACN). At room temperature, the ratio of k2/k1 for the three reactions was found to be around 0.50, 0.026, and 0.0072.

  3. The ozonolysis of primary aliphatic amines in fine particles

    Directory of Open Access Journals (Sweden)

    J. Zahardis

    2008-02-01

    Full Text Available The oxidative processing by ozone of the particulate amines octadecylamine (ODA and hexadecylamine (HDA is reported. Ozonolysis of these amines resulted in strong NO2 and NO3 ion signals that increased with ozone exposure as monitored by photoelectron resonance capture ionization aerosol mass spectrometry. These products suggest a mechanism of progressive oxidation of the particulate amines to nitroalkanes. Additionally, a strong ion signal at 125 m/z is assigned to the ion NO3 (HNO3. For ozonized mixed particles containing ODA or HDA + oleic acid (OL, with pO3≥3×10–7 atm, imine, secondary amide, and tertiary amide products were measured. These products most likely arise from reactions of amines with aldehydes (for imines and stabilized Criegee intermediates (SCI or secondary ozonides (for amides from the fatty acid. The routes to amides via SCI and/or secondary ozonides were shown to be more important than comparable amide forming reactions between amines and organic acids, using azelaic acid as a test compound. Finally, direct evidence is provided for the formation of a surface barrier in the ODA + OL reaction system that resulted in the retention of OL at high ozone exposures (up to 10−3 atm for 17 s. This effect was not observed in HDA + OL or single component OL particles, suggesting that it may be a species-specific surfactant effect from an in situ generated amide or imine. Implications to tropospheric chemistry, including particle bound amines as sources of oxidized gas phase nitrogen species (e.g.~NO2, NO3, formation of nitrogen enriched HULIS via ozonolysis of amines and source apportionment are discussed.

  4. Mutagenic activity and heterocyclic amine content of the human diet

    Energy Technology Data Exchange (ETDEWEB)

    Knize, M.G.; Dolbeare, F.A.; Cunningham, P.L.; Felton, J.S.

    1993-01-15

    The mutagenic activity and the mass amount of heterocyclic amines responsible for the mutagenic activity have been measured in some cooked foods. Cooked meats are the predominant source of mutagenic activity in the diet with values ranging from 0 to 10,000 revertants per gram reported in the Ames/Salmonelia test with strain TA98. Several heterocyclic amines are present and have been quantified using solid-phase extraction followed by HPLC. Frying at higher temperatures and for longer times produces the greatest mutagenic response, and concomitantly, the largest amounts of heterocyclic amines. Most of the mutagenic activity in fried meat samples can be accounted for by MelQx, DiMelQx and IQ, although other heterocylic amines are present and PHIP mutagenic activity becomes significant at higher temperatures. Non-meat products such as baked breads can also form significant mutagenic activity, particularly when overcooked. Commercially prepared hamburgers made from meat substitutes such as tofu, wheat gluten or tempeh and fried at 210{degrees}C have up to 10% of the mutagenic activity of a fried beef patty cooked under the same conditions. When detected, amounts of heterocyclic amines in fried beef patties range from a total of 0.35 ng/g for commercial beef hamburgers to 142 ng/g for a beef patty cooked over a barbecue. Dietary intake is expected to have a large range, from less than one microgram per day to over 50 micrograms per day based on current knowledge of known heterocyclic amine chemicals and heterocyclic amine-containing foods.

  5. Biogenic amines in Italian Pecorino cheese

    Directory of Open Access Journals (Sweden)

    Maria eSchirone

    2012-05-01

    Full Text Available The quality of distinctive artisanal cheeses is closely associated with the territory of production and its traditions. Pedoclimatic characteristics, genetic autochthonous variations and anthropic components create an environment so specific that it would be extremely difficult to reproduce elsewhere. Pecorino cheese is included in this sector of the market and is widely diffused in Italy (approximately 53.727t of production. Pecorino is a common name given to indicate Italian cheeses made exclusively from pure ewes' milk characterized by a high content of fat matter and it is mainly produced in the middle and south of Italy by traditional procedures from raw or thermized milk. The microbiota plays a major role in the development of the organoleptic characteristics of the cheese but it can also be responsible for the accumulation of undesirable substances, such as biogenic amines (BA. Several factors can contribute to the qualitative and quantitative profiles of BA’s in Pecorino cheese such as environmental hygienic conditions, pH, salt concentration, aw, fat content, pasteurization of milk, decarboxylase microorganisms, starter cultures, temperature and time of ripening, storage, part of the cheese (core, edge and the presence of cofactor. Generally, the total content of BA’s can range from about 100-2400 mg/kg, with a prevalence of toxicologically important BA’s, tyramine and histamine. The presence of BA in Pecorino cheeses is becoming increasingly important to consumers and cheese-maker alike, due to the potential threats of toxicity to humans and consequent trade implications.

  6. Can an amine be a stronger acid than a carboxylic acid? The surprisingly high acidity of amine-borane complexes.

    Science.gov (United States)

    Martín-Sómer, Ana; Lamsabhi, Al Mokhtar; Yáñez, Manuel; Dávalos, Juan Z; González, Javier; Ramos, Rocío; Guillemin, Jean-Claude

    2012-12-03

    The gas-phase acidity of a series of amine-borane complexes has been investigated through the use of electrospray mass spectrometry (ESI-MS), with the application of the extended Cooks kinetic method, and high-level G4 ab initio calculations. The most significant finding is that typical nitrogen bases, such as aniline, react with BH(3) to give amine-borane complexes, which, in the gas phase, have acidities as high as those of either phosphoric, oxalic, or salicylic acid; their acidity is higher than many carboxylic acids, such as formic, acetic, and propanoic acid. Indeed the complexation of different amines with BH(3) leads to a substantial increase (from 167 to 195 kJ mol(-1)) in the intrinsic acidity of the system; in terms of ionization constants, this increase implies an increase as large as fifteen orders of magnitude. Interestingly, this increase in acidity is almost twice as large as that observed for the corresponding phosphine-borane analogues. The agreement between the experimental and the G4-based calculated values is excellent. The analysis of the electron-density rearrangements of the amine and the borane moieties indicates that the dative bond is significantly stronger in the N-deprotonated anion than in the corresponding neutral amine-borane complex, because the deprotonated amine is a much better electron donor than the neutral amine. On the top of that, the newly created lone pair on the nitrogen atom in the deprotonated species, conjugates with the BN bonding pair. The dispersion of the extra electron density into the BH(3) group also contributes to the increased stability of the deprotonated species. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Yb(OTf){sub 3}-catalyzed one-pot three component synthesis for tertiary amines

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Bum Seok; Kim, Ji Hye; Nam, Tae Kyu; Jang, Doo Ok [Dept. of Chemistry, Yonsei University, Wonju (Korea, Republic of)

    2015-07-15

    Tertiary amine functionality is found in many natural bioactive products such as alkaloids, amino acids, nucleic acids, pharmaceuticals, and agrochemicals. Tertiary amines have also been used as building blocks for nitrogen-containing organic compounds and synthetic polymers. A one-pot method for direct reductive amination of aldehydes has been developed to synthesize tertiary amines using HMDS as a nitrogen source in the presence of Yb(OTf ){sub 3}. With a stoichiometric amount of HMDS, the reaction afforded the desired tertiary amines without competitive reduction of the parent carbonyl compounds. This reaction offers a convenient and efficient protocol for synthesizing aromatic and aliphatic tertiary amines under mild reaction conditions.

  8. Choosing amine-based absorbents for CO2 capture.

    Science.gov (United States)

    Gomes, João; Santos, Samuel; Bordado, João

    2015-01-01

    CO2 capture from gaseous effluents is one of the great challenges faced by chemical and environmental engineers, as the increase in CO2 levels in the Earth atmosphere might be responsible for dramatic climate changes. From the existing capture technologies, the only proven and mature technology is chemical absorption using aqueous amine solutions. However, bearing in mind that this process is somewhat expensive, it is important to choose the most efficient and, at the same time, the least expensive solvents. For this purpose, a pilot test facility was assembled and includes an absorption column, as well as a stripping column, a heat exchanger between the two columns, a reboiler for the stripping column, pumping systems, surge tanks and all necessary instrumentation and control systems. Some different aquous amine solutions were tested on this facility and it was found that, from a set of six tested amines, diethanol amine is the one that turned out to be the most economical choice, as it showed a higher CO2 loading capacity (0.982 mol of CO2 per mol of amine) and the lowest price per litre (25.70 €/L), even when compared with monoethanolamine, the benchmark solvent, exhibiting a price per litre of 30.50 €/L.

  9. Chromosomal localization of the human vesicular amine transporter genes

    Energy Technology Data Exchange (ETDEWEB)

    Peter, D.; Finn, P.; Liu, Y.; Roghani, A.; Edwards, R.H.; Klisak, I.; Kojis, T.; Heinzmann, C.; Sparkes, R.S. (UCLA School of Medicine, Los Angeles, CA (United States))

    1993-12-01

    The physiologic and behavioral effects of pharmacologic agents that interfere with the transport of monoamine neurotransmitters into vesicles suggest that vesicular amine transport may contribute to human neuropsychiatric disease. To determine whether an alteration in the genes that encode vesicular amine transport contributes to the inherited component of these disorders, the authors have isolated a human cDNA for the brain transporter and localized the human vesciular amine transporter genes. The human brain synaptic vesicle amine transporter (SVAT) shows unexpected conservation with rat SVAT in the regions that diverge extensively between rat SVAT and the rat adrenal chromaffin granule amine transporter (CGAT). Using the cloned sequences with a panel of mouse-human hybrids and in situ hybridization for regional localization, the adrenal CGAT gene (or VAT1) maps to human chromosome 8p21.3 and the brain SVAT gene (or VAT2) maps to chromosome 10q25. Both of these sites occur very close to if not within previously described deletions that produce severe but viable phenotypes. 26 refs., 3 figs., 1 tab.

  10. In situ infrared study of the effect of amine density on the nature of adsorbed CO2 on amine-functionalized solid sorbents.

    Science.gov (United States)

    Tumuluri, Uma; Isenberg, Mathew; Tan, Chung-Sung; Chuang, Steven S C

    2014-07-01

    In situ Fourier transform infrared spectroscopy was used to determine the nature of adsorbed CO2 on class I (amine-impregnated) and class II (amine-grafted) sorbents with different amine densities. Adsorbed CO2 on amine sorbents exists in the form of carbamate-ammonium ion pairs, carbamate-ammonium zwitterions, and carbamic acid. The adsorbed CO2 on high-amine density sorbents showed that the formation of ammonium ions correlates with the suppression of CH stretching intensities. An HCl probing technique was used to resolve the characteristic infrared bands of ammonium ions, clarifying that the band observed around 1498 cm(-1) is a combination of the deformation vibration of ammonium ion (NH3(+)) at 1508 and 1469 cm(-1) and the deformation vibration of NH in carbamate (NHCOO(-)) at 1480 cm(-1). Carbamate and carbamic acid on sorbents with low amine density desorbed at a rate faster than those on sorbents with high amine density after switching the flow from CO2 to Ar at 55 °C. Evaluation of the desorption temperature profiles showed that the temperature required to achieve the maximal desorption of CO2 (Tmax. des) increases with amine density. The adsorbed CO2 on sorbents with high amine density is stabilized via hydrogen bonding interactions with adjacent amine sites. These sorbents require higher temperature to desorb CO2 than those with low amine density.

  11. Approches novatrices pour la création d'emplois pour les jeunes et ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    En Afrique de l'Est, malgré des taux de croissance impressionnants, la réduction de la pauvreté et la création d'emplois demeurent limitées, en particulier pour les jeunes. Compte tenu de l'ampleur de la croissance démographique en Afrique et de l'inaptitude du secteur structuré à créer des emplois pour les jeunes, ...

  12. De meilleurs emplois pour l'Asie

    International Development Research Centre (IDRC) Digital Library (Canada)

    Offrir de meilleurs emplois en Asie exigera des interventions créatives de la part des gouvernements, des employeurs et des entrepreneurs. Le CRDI aide les établisse- ments de recherche à trouver des .... de dollars en 2014, ont entraîné une expansion majeure des emplois pour les. Bangladaises. On s'attend à ce que ...

  13. Pharmacological potential of biogenic amine-polyamine interactions beyond neurotransmission.

    Science.gov (United States)

    Sánchez-Jiménez, F; Ruiz-Pérez, M V; Urdiales, J L; Medina, M A

    2013-09-01

    Histamine, serotonin and dopamine are biogenic amines involved in intercellular communication with multiple effects on human pathophysiology. They are products of two highly homologous enzymes, histidine decarboxylase and l-aromatic amino acid decarboxylase, and transmit their signals through different receptors and signal transduction mechanisms. Polyamines derived from ornithine (putrescine, spermidine and spermine) are mainly involved in intracellular effects related to cell proliferation and death mechanisms. This review summarizes structural and functional evidence for interactions between components of all these amine metabolic and signalling networks (decarboxylases, transporters, oxidases, receptors etc.) at cellular and tissue levels, distinct from nervous and neuroendocrine systems, where the crosstalk among these amine-related components can also have important pathophysiological consequences. The discussion highlights aspects that could help to predict and discuss the effects of intervention strategies. © 2013 The Authors. British Journal of Pharmacology © 2013 The British Pharmacological Society.

  14. Amine Metabolism Is Influenced by Dietary Protein Source

    Directory of Open Access Journals (Sweden)

    Soumya K. Kar

    2017-09-01

    Full Text Available Growth in world population will inevitably leads to increased demand for protein for humans and animals. Protein from insects and blood plasma are being considered as possible alternatives, but more research on their nutritional quality and health effects is needed. Here, we studied the effect of dietary protein source on metabolism and metabolic amine profiles in serum and urine of mice. Groups of mice were fed semi-purified diets containing 300 g/kg of soybean meal, casein, partially delactosed whey powder, spray-dried plasma protein, wheat gluten meal, and yellow mealworm. Feed and water intake as well as body weight gain were measured for 28 days. After 14 and 28 days, serum and urine samples were collected for measurement of a large panel of amine metabolites. MetaboAnalyst 3.0 was used for analysis of the raw metabolic data. Out of 68 targeted amine metabolites, we could detect 54 in urine and 41 in blood serum. Dietary protein sources were found to have profound effects on host metabolism, particularly in systemic amine profiles, considered here as an endophenotype. We recommend serum over urine to screen for the amine metabolic endophenotype based on partial least squares discriminant analysis. We concluded that metabolites like alpha-aminobutyric acid and 1-methylhistidine are sensitive indicators of too much or too little availability of specific amino acids in the different protein diets. Furthermore, we concluded that amine metabolic profiles can be useful for assessing the nutritional quality of different protein sources.

  15. Une alternative au cobalt pour la synthese de nanotubes de carbone monoparoi par plasma inductif thermique

    Science.gov (United States)

    Carrier, Jean-Francois

    Les nanotubes de carbone de type monoparoi (C-SWNT) sont une classe recente de nanomateriaux qui ont fait leur apparition en 1991. L'interet qu'on leur accorde provient des nombreuses proprietes d'avant-plan qu'ils possedent. Leur resistance mecanique serait des plus rigide, tout comme ils peuvent conduire l'electricite et la chaleur d'une maniere inegalee. Non moins, les C-SWNT promettent de devenir une nouvelle classe de plateforme moleculaire, en servant de site d'attache pour des groupements reactifs. Les promesses de ce type particulier de nanomateriau sont nombreuses, la question aujourd'hui est de comment les realiser. La technologie de synthese par plasma inductif thermique se situe avantageusement pour la qualite de ses produits, sa productivite et les faibles couts d'operation. Par contre, des recherches recentes ont permis de mettre en lumiere des risques d'expositions reliees a l'utilisation du cobalt, comme catalyseur de synthese; son elimination ou bien son remplacement est devenu une preoccupation importante. Quatre recettes alternatives ont ete mises a l'essai afin de trouver une alternative plus securitaire a la recette de base; un melange catalytique ternaire, compose de nickel, de cobalt et d'oxyde d'yttrium. La premiere consiste essentiellement a remplacer la proportion massique de cobalt par du nickel, qui etait deja present dans la recette de base. Les trois options suivantes contiennent de nouveaux catalyseurs, en remplacement au Co, qui sont apparus dans plusieurs recherches scientifiques au courant des dernieres annees: le dioxyde de zircone (ZrO2), dioxyde de manganese (MnO2) et le molybdene (Mo). La methode utilisee consiste a vaporiser la matiere premiere, sous forme solide, dans un reacteur plasma a haute frequence (3 MHz) a paroi refroidi. Apres le passage dans le plasma, le systeme traverse une section dite de "croissance", isolee thermiquement a l'aide de graphite, afin de maintenir une certaine plage de temperature favorable a la

  16. Cartographie des especes de feuilles vegetales utilisees comme ...

    African Journals Online (AJOL)

    Les feuilles de Tectona grandis, de Cola cordifolia, de Thalia geniculata, de Ficus platyphylla et de Piliostigma thonningii sont répandues au Centre et au Nord du pays. Les feuilles de Manihot esculenta, de Theobroma cacao et de Colocasia esculenta se retrouvent surtout au Centre du pays, tandis que les feuilles des épis ...

  17. Biogenic amines in smear and mould-ripened cheeses

    Directory of Open Access Journals (Sweden)

    Pavel Pleva

    2014-02-01

    Full Text Available The aim of the study was the monitoring of six biogenic amines (histamine, tyramine, phenylethylamine, tryptamine, putrescine, and cadaverine and two polyamines (spermidine and spermine in 30 samples of dairy products purchased in the Czech Republic, namely in 15 samples of mould-ripened cheeses and in 15 samples of smear-ripened cheeses. A further goal was the microbiological analysis of the individual samples of cheeses (total count of microorganisms, number of enterobacteria, enterococci, lactic acid bacteria, yeasts and moulds. The monitored biogenic amines were analyzed by a high performance liquid chromatography equipped with a UV/VIS DAD detector. The amount of enterobacteria in fresh cheese exceeded 105 CFU.g‑1. In smear-ripened cheese flavourless (Romadur type, the amount was >103 CFU.g-1 and 104-105 CFU.g-1 in smear-ripened cheese with flavour. Biogenic amines were observed in two groups of blue cheeses (white veined cheese and blue veined cheese and smear-ripened cheeses. In both groups, there is a possibility of the presence of biogenic amines because the number of microorganisms and concentration of free amino acids increase during ripening. In ten samples of soft smear-ripening acid cheese and in smear-ripened cheese, the total content of biogenic amines were 22-1000 mg.kg-1 and in 5 samples of these cheeses, it was in range 1000-6000 mg.kg-1. The total amount of biogenic amines in the blue cheeses were in range 40-600 mg.kg-1. The presense of the tyramine was observed in the all analysed cheeses. The tyramine producing strains generated more than 900 mg.kg-1 of this biogenic amine. The production of tryptamine in the analysed cheeses was not proved by this study. The results of this study show that biogenic amines and polyamines are common in cheese. However, in some cases, they can pose a significant health danger for consumers. Any legislative control authority does not monitor them, as they are secondary metabolites even

  18. Mesoporous amine-bridged polysilsesquioxane for CO2 capture

    KAUST Repository

    Qi, Genggeng

    2011-01-01

    A novel class of amine-supported sorbents based on amine-bridged mesoporous polysilsesquioxane was developed via a simple one-pot sol-gel process. The new sorbent allows the incorporation of a large amount of active groups without sacrificing surface area or pore volume available for CO2 capture, leading to a CO2 capture capacity of 3.2 mmol g−1 under simulated flue gas conditions. The sorbent is readily regenerated at 100°C and exhibits good stability over repetitive adsorption-desorption cycling.

  19. Determination of Biogenic Amines in Different Shrimp Species for Export

    International Nuclear Information System (INIS)

    Myat Myat Thaw; Oo Aung; Aung Myint; Bisswanger, Hans

    2004-06-01

    This study is part of the project on the ''Quality Assurance of Different Shrimp Species for Export''. Local shrimp samples were collected from Ministry of Livestock and Fisheries and various private enterprises. Contents of biogenic amines were determined by using benzoyl chloride derivatization method with HPLC (reverse phase high performance liquid chromatography). Based on the biogenic amines, quality index of shrimps were correlated with freshness index so that the grade of shrimp samples can be classified as excellent, good, and acceptable. All sizes of shrimps such as extra large, large, medium were found to excceptable respectively

  20. Status of application of amines in US PWRs

    Energy Technology Data Exchange (ETDEWEB)

    Millett, P.J. [iSagacity, Half Moon Bay, CA (United States); Fruzzetti, K. [Electric Power Reserch Inst., Palo Alto, CA (United States)

    2005-10-01

    Prior to 1990, the majority of US units with pressurized water reactors (PWRs) were using ammonia as the primary pH control agent in secondary systems. Morpholine was used in one plant that did not employ condensate polishers. With the introduction of ethanolamine and other advanced amines in 1992, US PWRs could now get the benefit of improved pH control and still operate condensate polishers in the H-OH form. In this paper, the current practice with amines in US PWRs is reviewed with consideration for the optimization of pH control in secondary systems. (orig.)

  1. Enzymatic network for production of ether amines from alcohols

    DEFF Research Database (Denmark)

    Palacio, Cyntia M.; Crismaru, Ciprian G.; Bartsch, Sebastian

    2016-01-01

    We constructed an enzymatic network composed of three different enzymes for the synthesis of valuable ether amines. The enzymatic reactions are interconnected to catalyze the oxidation and subsequent transamination of the substrate and to provide cofactor recycling. This allows production...... for reactions containing 10mM alcohol and up to 280mM ammonia corresponded well to predicted conversions. The results indicate that efficient amination can be driven by high concentrations of ammonia and may require improving enzyme robustness for scale-up....

  2. Amine functionalization of carbon nanotubes for the preparation of CNT based polyactide composites - A comparative study

    CSIR Research Space (South Africa)

    Kesavan Pillai, Sreejarani

    2011-11-01

    Full Text Available This work describes a comparison between two chemical functionalization strategies for the amine functionalization of carbon nanotubes (CNTs). In the first procedure, the CNTs are functionalized in direct amination process that avoids the use...

  3. Monomers for thermosetting and toughening epoxy resins. [glycidyl amine derivatives, propargyl-containing amines, and mutagenic testing of aromatic diamines

    Science.gov (United States)

    Pratt, J. R.

    1981-01-01

    Eight glycidyl amines were prepared by alkylating the parent amine with epichlorohydrin to form chlorohydrin, followed by cyclization with aqueous NaOH. Three of these compounds contained propargyl groups with postcuring studies. A procedure for quantitatively estimating the epoxy content of these glycidyl amines was employed for purity determination. Two diamond carbonates and several model propargly compounds were prepared. The synthesis of three new diamines, two which contain propargyloxy groups, and another with a sec-butyl group is in progress. These materials are at the dinitro stage ready for the final hydrogenation step. Four aromatic diamines were synthesized for mutagenic testing purposes. One of these compounds rapidly decomposes on exposure to air.

  4. A protocol for amide bond formation with electron deficient amines and sterically hindered substrates

    DEFF Research Database (Denmark)

    Due-Hansen, Maria E; Pandey, Sunil K; Christiansen, Elisabeth

    2016-01-01

    A protocol for amide coupling by in situ formation of acyl fluorides and reaction with amines at elevated temperature has been developed and found to be efficient for coupling of sterically hindered substrates and electron deficient amines where standard methods failed.......A protocol for amide coupling by in situ formation of acyl fluorides and reaction with amines at elevated temperature has been developed and found to be efficient for coupling of sterically hindered substrates and electron deficient amines where standard methods failed....

  5. Where is Idi Amin? On violence, ethics and social memory in Africa ...

    African Journals Online (AJOL)

    The former Uganda dictator, Amin Dada, recently died in a Saudi hospital, after spending the last twenty four years of his life in exile. Given Amin's brutal dictatorship and the notoriety of his regime in. Uganda one would have expected that there has been a lot of public discussion about Amin's legacy and his continuing ...

  6. Mechanism of the N-Hydroxylation of Primary and Secondary Amines by Cytochrome P450

    DEFF Research Database (Denmark)

    Seger, Signe T.; Rydberg, Patrik; Olsen, Lars

    2015-01-01

    Cytochrome P450 enzymes (CYPs) metabolize alkyl- and arylamines, generating several different products. For the primary and secondary amines, some of these reactions result in hydroxylated amines, which may be toxic. Thus, when designing new drugs containing amine groups, it is important to be able...

  7. Laboratory evaluation of borate:amine:copper derivatives In wood for fungal decay protection

    Science.gov (United States)

    George Chen

    2011-01-01

    This study aimed to evaluate borate:amine:copper derivatives in wood for fungal decay protection as well as the permanence of copper and boron in wood. Each of four derivatives of borate:amine:copper prevented fungal decay in wood. Disodium tetraborate decahydrate (borax):amine:copper derivatives with 0.61-0.63% retention after water leaching prevented decay by...

  8. Thermal properties of wood reacted with a phosphorus pentoxide–amine system

    Science.gov (United States)

    Hong-Lin Lee; George C. Chen; Roger M. Rowell

    2004-01-01

    The objective of this research was to improve the fire-retardant properties of wood in one treatment using a phosphorus pentoxide–amine system. Phosphorus pentoxide and 16 amines including alkyl, halophenyl, and phenyl amines were compounded in N,N-dimethylformamide and the resulting solutions containing phosphoramides were reacted with wood. The characteristics of...

  9. Preparation and characterization of amine-functionalized sugarcane bagasse for CO2 capture.

    Science.gov (United States)

    Luo, Shihe; Chen, Siyu; Chen, Shuixia; Zhuang, Linzhou; Ma, Nianfang; Xu, Teng; Li, Qihan; Hou, Xunan

    2016-03-01

    A low-cost solid amine adsorbent for CO2 capture was prepared by using sugarcane bagasse (SB), a dominant agro-industrial residue in the sugar and alcohol industry as raw materials. In this preparation process, acrylamide was grafted on SB, and the grafted fiber was then aminated with different type of amine reagents to introduce primary and secondary amine groups onto the surface of SB fibers. The graft and amination conditions were optimized. The prepared solid amine adsorbent showed remarkable CO2 adsorption capacity and the adsorption capacity of the solid amine adsorbent could reach 5.01 mmol CO2/g at room temperature. The comparison of adsorption capacities of amine fibers aminated with various amination agents demonstrated that fibers aminated with triethylenetetramine would obtain higher adsorption capacities and higher amine efficiency. These adsorbents also showed good regeneration performance, the regenerated adsorbent could maintain almost the same adsorption capacity for CO2 after 10 recycles. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Blue Chitin columns for the extraction of heterocyclic amines from urine samples

    DEFF Research Database (Denmark)

    Bang, J.; Frandsen, Henrik Lauritz; Skog, K.

    2004-01-01

    During normal cooking of meat, a class of mutagenic/carcinogenic compounds called heterocyclic amines is formed. Heterocyclic amines are rapidly absorbed and metabolised in the human body, and for estimation of the intake of heterocyclic amines, it is useful to determinate their levels in the uri...

  11. Blue Chitin columns for the extraction of heterocyclic amines from urine samples

    DEFF Research Database (Denmark)

    Bang, J.; Frandsen, Henrik Lauritz; Skog, K.

    2004-01-01

    . Blue Chitin columns were used for the extraction and purification of heterocyclic amines from urine samples spiked with 14 different heterocyclic amines. The samples were analysed using LC-MS. The results show that Blue Chitin columns provide a straightforward and rapid means of extracting heterocyclic...... amines from urine samples, and that Blue Chitin column are also useful in the purification of urinary metabolites....

  12. Super absorbent conjugated microporous polymers: a synergistic structural effect on the exceptional uptake of amines.

    Science.gov (United States)

    Liu, Xiaoming; Xu, Yanhong; Guo, Zhaoqi; Nagai, Atsushi; Jiang, Donglin

    2013-04-21

    Conjugated microporous polymers exhibit a synergistic structural effect on the exceptional uptake of amines, whereas the dense porphyrin units facilitate uptake, the high porosity offers a large interface and the swellability boosts capacity. They are efficient in the uptake of both vapor and liquid amines, are applicable to various types of amines, and are excellent for cycle use.

  13. Metal mediated amination of aromatic rings following carbon ...

    Indian Academy of Sciences (India)

    Administrator

    Metal-mediated reactions which result in addition of [NR]2– fragments belong to a reaction class of fundamental importance in chemistry in connection with carbon- nitrogen bond formation processes. In this presentation we wish to report our results on aromatic ring amination of a pendant phenyl ring of coordinated ...

  14. Electrodeposition of amine-terminatedpoly(ethylene glycol) to titanium surface

    International Nuclear Information System (INIS)

    Tanaka, Yuta; Doi, Hisashi; Iwasaki, Yasuhiko; Hiromoto, Sachiko; Yoneyama, Takayuki; Asami, Katsuhiko; Imai, Hachiro; Hanawa, Takao

    2007-01-01

    The immobilization of poly(ethylene glycol), PEG, to a solid surface is useful to functionalize the surface, e.g., to prevent the adsorption of proteins. No successful one-stage technique for the immobilization of PEG to base metals has ever been developed. In this study, PEG in which both terminals or one terminal had been modified with amine bases was immobilized onto a titanium surface using electrodeposition. PEG was dissolved in a NaCl solution, and electrodeposition was carried out at 310 K with - 5 V for 300 min. The thickness of the deposited PEG layer was evaluated using ellipsometry, and the bonding manner of PEG to the titanium surface was characterized using X-ray photoelectron spectroscopy after electrodeposition. The results indicated that a certain amount of PEG was adsorbed on titanium through both electrodeposition and immersion when PEG was terminated by amine. However, terminated amines existed at the surface of titanium and were combined with titanium oxide as N-HO by electrodeposition, while amines randomly existed in the molecule and showed an ionic bond with titanium oxide by immersion. The electrodeposition of PEG was effective for the inhibition of albumin adsorption. This process is useful for materials that have electroconductivity and a complex morphology

  15. Cloud condensation nuclei activity of aliphatic amine secondary aerosol

    Science.gov (United States)

    Aliphatic amines can form secondary aerosol via oxidation with atmospheric radicals (e.g. hydroxyl radical and nitrate radical). The resulting particle composition can contain both secondary organic aerosol (SOA) and inorganic salts. The fraction of organic to inorganic materials in the particulate ...

  16. INTEGRASI ILMU-ILMU KEISLAMAN DALAM PERSPEKTIF M. AMIN ABDULLAH

    Directory of Open Access Journals (Sweden)

    Parluhutan Siregar

    2014-12-01

    Full Text Available The Integration of Islamic Sciences in the Perspective of M. Amin Abdullah. Criticism on the pattern of Islamic sciences development in Indonesia, especially at the level of Islamic religious higher education, has caught the attension of many critiques. This essay tries to analytically describe M. Amin Abdullah’s thought who promotes the concept of Islamic sciences integration. The writer maintains that Islamic sciences thus far, have still fragmentary in nature and have not yet interconnected with contemporary issues. As such, it is required to build the epistemology of integrated and interconnected science. The writer finds that theo-anthropocentric-integralistic epistemology of science of Amin Abdullah is developed against the backdrop of classification of science. His theory departs from the Qur’an and Sunnah, ‘Ulûm al-Dîn, al-Fikr al-Islâmy, and Dirâsah al-Islâmiyyah. Those categories of Islamic sciences are drawn by Amin Abdullah into four-layered concept mapping of spider web. Such epistemology combines all disciplines of social and religious sciences vis a vis contemporary issues.

  17. Isomerization of metastable amine radical cations by dissociation-recombination

    DEFF Research Database (Denmark)

    Pedersen, Anders Holmen; Nielsen, Christian Benedikt; Bojesen, Gustav

    2015-01-01

    The metastable molecular ions of primary aliphatic amines branched at C2 can isomerize by cleavage-recombination, thereby facilitating fragmentation reactions that require less energy than simple cleavage of the initial molecular ion. This process complements the reactions described by Audier...

  18. The repertoire of trace amine G-protein-coupled receptors

    DEFF Research Database (Denmark)

    Gloriam, David E.; Bjarnadóttir, Thóra K; Yan, Yi-Lin

    2005-01-01

    eukaryotic species for receptors similar to the mammalian trace amine (TA) receptor subfamily. We identified 18 new receptors in rodents that are orthologous to the previously known TA-receptors. Remarkably, we found 57 receptors (and 40 pseudogenes) of this type in the zebrafish (Danio rerio), while fugu...

  19. Metal mediated amination of aromatic rings following carbon ...

    Indian Academy of Sciences (India)

    Administrator

    Metal mediated amination of aromatic rings following carbon-nitrogen bond formation and the coordination chemistry thereof. AMRITA SAHA, AMIT K GHOSH, PARTHA MAJUMDAR and. SREEBRATA GOSWAMI. Department of Inorganic Chemistry, Indian Association for the Cultivation of. Science, Calcutta 700 032, India.

  20. Linear free energy relationship in reactions between diphenyl amine ...

    Indian Academy of Sciences (India)

    Unknown

    Minimal structural effects observed are attributed to the fact that the isokinetic temperature of the reaction is close to the reaction temperature. Keywords. Diphenyl amine; substituent effect; reaction constant; isokinetic temperature; linear free energy relationship. 1. Introduction. Nucleophilic substitution at the benzylic carbon ...

  1. Linear free energy relationship in reactions between diphenyl amine ...

    Indian Academy of Sciences (India)

    Rate of reaction between benzyl bromide and diphenyl amine is retarded by electron-donating groups and enhanced by electron-withdrawing groups present on the benzene ring of the substrate. Hammett's reaction constant of the reaction decreases with increase in temperature according to the equation,. \\rho = -11.92 + ...

  2. Preparation and adsorption property of aminated cross linking ...

    Indian Academy of Sciences (India)

    Administrator

    Preparation and adsorption property of aminated cross linking microbeads of GMA/EGDMA for bilirubin. ZHIPING CHEN, BAOJIAO GAO* and XIAOFENG YANG. Department of Chemical Engineering, North University of China, Taiyuan, 030051, China e-mail: gaobaojiao@126.com. MS received 17 December 2008; revised ...

  3. Zinc catalyzed Guanylation reaction of Amines with Carbodiimides ...

    Indian Academy of Sciences (India)

    ... Journal of Chemical Sciences; Volume 128; Issue 6. Zinc catalyzed Guanylation reaction of Amines with Carbodiimides/ Isocyanate leading to Guanidines/Urea derivatives formation. JAYEETA BHATTACHARJEE MITALI SACHDEVA INDRANI BANERJEE TARUN K PANDA. Regular Article Volume 128 Issue 6 June 2016 ...

  4. Monofunctional primary amine: A new class of organocatalyst for ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 129; Issue 3 ... A new class of organocatalysts involving a primary amine as the only functional group is developed for catalytic asymmetric aldol reaction of cyclohexanone/ cyclopentanone with various aryl aldehydes in thepresence of benzoic acid as an additive at ...

  5. Linear free energy relationship in reactions between diphenyl amine ...

    Indian Academy of Sciences (India)

    Unknown

    close to the reaction temperature. Keywords. Diphenyl amine; substituent effect; reaction constant; isokinetic temperature; linear free energy relationship. 1. Introduction. Nucleophilic substitution at the benzylic carbon is of broad synthetic utility and has received considerably significant attention from organic chemists. Funda ...

  6. Zinc catalyzed Guanylation reaction of Amines with Carbodiimides ...

    Indian Academy of Sciences (India)

    DOI 10.1007/s12039-016-1096-y. Zinc catalyzed Guanylation reaction of Amines with Carbodiimides/ ... A possible mechanism involving penta-coordinated zinc transition state for the catalytic reaction is presented. Keywords. Carbodiimide ... or receptors through hydrogen bonds and electrostatic interactions. They are ...

  7. incidence of biogenic amines in foods implications for the gambia

    African Journals Online (AJOL)

    Temechegn

    Health-wise biogenic amines play positive roles and ... BAs include, fish, fish products, meat products, eggs, cheeses, fermented vegetables, soybean ... The amount of. BAs present in foods, fruits and vegetables provides an index for measuring food quality [3]. In the tropics fish are caught in temperatures more than 200C.

  8. Efficient acetylation of primary amines and amino acids in ...

    Indian Academy of Sciences (India)

    Abstract. Acetyl chloride is one of the most commonly available and cheap acylating agent but its high reactivity and concomitant instability in water precludes its use to carry out acetylation in aqueous medium. The present methodology illustrates the efficient acetylation of primary amines and amino acids in brine solution ...

  9. Monofunctional primary amine: A new class of organocatalyst for ...

    Indian Academy of Sciences (India)

    for catalytic asymmetric aldol reaction of cyclohexanone/cyclopentanone with various aryl aldehydes in the presence of benzoic ... reactions gave excellent yield and good to excellent stereoselectivity, while secondary amines were found to have little or no ...... alytic anti-Mannich and syn-Aldol Reactions J. Am. Chem. Soc.

  10. Hydrothermal synthesis and characterisation of amine-templated ...

    African Journals Online (AJOL)

    Hydrothermal synthesis and characterisation of amine-templated metal phosphate framework. ... The complexes were thermally stable up to 3000C, after which the organic components starts decomposing. The solubility test in a wide spectrum of solvents (at room temperature) showed that the complexes were insoluble in ...

  11. Efficient acetylation of primary amines and amino acids in ...

    Indian Academy of Sciences (India)

    This effort represents the first efficient use of this most reactive but cheap acetylating agent to acetylate amines in excellent yields in aqueous medium. This is a potentially useful green chemical transformation where reaction takes place in environment-friendly brine solution leading to easy work-up and isolation of the ...

  12. METALCOMPLEXES OF TELLURIUM-CONTAINING AMINES AND AZOMETINES

    Directory of Open Access Journals (Sweden)

    G. M. Abakarov

    2014-01-01

    Full Text Available In this article methods of synthesis and reactionary ability of metalcomplexes of tellurium-containing amines, azometines, of a problem of competitive coordination with use of the principle of "soft" and "rigid" acids and the bases (R. Pearson.

  13. Experimental and theoretical investigations into the stability of cyclic aminals

    Directory of Open Access Journals (Sweden)

    Edgar Sawatzky

    2016-10-01

    Full Text Available Background: Cyclic aminals are core features of natural products, drug molecules and important synthetic intermediates. Despite their relevance, systematic investigations into their stability towards hydrolysis depending on the pH value are lacking.Results: A set of cyclic aminals was synthesized and their stability quantified by kinetic measurements. Steric and electronic effects were investigated by choosing appropriate groups. Both molecular mechanics (MM and density functional theory (DFT based studies were applied to support and explain the results obtained. Rapid decomposition is observed in acidic aqueous media for all cyclic aminals which occurs as a reversible reaction. Electronic effects do not seem relevant with regard to stability, but the magnitude of the conformational energy of the ring system and pKa values of the N-3 nitrogen atom.Conclusion: Cyclic aminals are stable compounds when not exposed to acidic media and their stability is mainly dependent on the conformational energy of the ring system. Therefore, for the preparation and work-up of these valuable synthetic intermediates and natural products, appropriate conditions have to be chosen and for application as drug molecules their sensitivity towards hydrolysis has to be taken into account.

  14. Understanding the political economy of contemporary Africa | Amin ...

    African Journals Online (AJOL)

    Further readings, offering a critique of 'post modernist' sociology and cultural studies (see, for instance, Samir Amin, The Liberal Virus, Pluto 2004, pages 19 et seq.) complete the picture of the ongoing intellectual disaster. CODESRIA constitutes an important intellectual locus conducting real open debates with a strong ...

  15. Pitié pour les grandes villes !

    Directory of Open Access Journals (Sweden)

    Jérôme Monnet

    1997-02-01

    Full Text Available Roger Caillois disait, en 1938, qu´il existe "une représentation de la grande ville, assez puissante sur les imaginations pour que jamais en pratique ne soit posée la question de son exactitude, créée de toute pièce par le livre, assez répandue néanmoins pour faire partie de l´atmosphère mentale collective et posséder par suite une certaine force de contrainte"(Le mythe et l´homme, p.156 [c´est lui qui souligne]. En 1996, la presse française a consacré dossiers et articles à "Habitat II...

  16. The acidity function of diethyl amine and triethyl amine in aqueous solutions; Funcion de acidez de disoluciones de dietilamina y trietilamina

    Energy Technology Data Exchange (ETDEWEB)

    Verdu, J. [Departamento de Quimica Fisica, Universidad de Valladolid (Spain)

    1995-12-31

    The acidity function of diethyl amine (DEA) and triethyl amine (TEA) in aqueous solutions, ethanolic solutions and ethanol-water mixtures has been determined spectrophotometrically, using as indicator butanol 2,4-dinitrophenylhydrazine. The acidity function lies within the range from 12.5 to 14.2. The basicity of solutions increases with the water content, and the order of basicity of the amines is TEA

  17. Transglutaminase-catalyzed amination of pea protein peptides using the biogenic amines histamine and tyramine.

    Science.gov (United States)

    Lu, Xinyao; Hrynets, Yuliya; Betti, Mirko

    2017-06-01

    Biogenic amines (BAs) are produced by the enzymatic decarboxylation of amino acids, and are well-known for their toxicity to humans. This study describes a new method using microbial transglutaminase (MTGase) to covalently link BAs such as histamine (HIS) and tyramine (TYR) to the glutamine residues of alcalase-hydrolyzed pea protein (PPH). The incubation of PPH and HIS and TYR in the presence of MTGase at 37 °C led to the formation of conjugates, as determined by liquid chromatography, after derivatization with dansyl chloride. Seventy-six % of HIS and 65% of TYR were covalently incorporated to PPH by MTGase. The incubation of PPH and TYR in the presence of MTGase exhibited a 52% DPPH radical scavenging activity at 10 mg mL -1 . Conjugation via MTGase improved the antioxidant status by reducing lipid peroxidation. This study emphasizes that the application of MTGase can effectively reduce histamine and tyramine content while simultaneously enhancing antioxidative capacity of PPH. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  18. Poly(amido amine)s as gene delivery vectors: effects of quaternary nicotinamide moieties in the side chains

    NARCIS (Netherlands)

    Mateos timoneda, Miguel; Lok, Martin C.; Hennink, Wim E.; Feijen, Jan; Engbersen, Johannes F.J.

    2008-01-01

    To evaluate the effect of quaternary nicotinamide pendant groups on gene delivery properties, a series of poly(amido amine) (co)polymers were synthesized by Michael addition polymerization of N, N-cystaminebisacrylamide with variable ratios of 1-(4-aminobutyl)-3-carbamoylpyridinium (Nic-BuNH2), and

  19. Analysis of a Buchwald-Hartwig amination: reaction for pharmaceutical production

    DEFF Research Database (Denmark)

    Christensen, Henrik

    is to increase the understanding of the chem­ical reaction mechanisms and kinetics for the Buchwald-Hartwig amination reaction. Also, to develop methods for application of these mechanisms and kinetics to optimize and scale up an organic synthesis to an industrial phar­maceutical production. The Buchwald......The Buchwald-Hartwig amination reaction is widely used in the production of N-arylated amines in the pharmaceutical industry. The reaction is betweenan aryl halogen and a primary or secondary amine in the presence of a base and a homogeneous catalyst giving the desired N-arylated amine. Due to mild...

  20. Analysis of a Buckwald-Hartwig amination: reaction for pharmaceutical production

    DEFF Research Database (Denmark)

    Christensen, Henrik; Kiil, Søren; Dam-Johansen, Kim

    is to increase the understanding of the chem­ical reaction mechanisms and kinetics for the Buchwald-Hartwig amination reaction. Also, to develop methods for application of these mechanisms and kinetics to optimize and scale up an organic synthesis to an industrial phar­maceutical production. The Buchwald......The Buchwald-Hartwig amination reaction is widely used in the production of N-arylated amines in the pharmaceutical industry. The reaction is betweenan aryl halogen and a primary or secondary amine in the presence of a base and a homogeneous catalyst giving the desired N-arylated amine. Due to mild...

  1. Centre de recherches pour le développement international ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    André Lavoie

    Pour tous les gouverneurs à l'exclusion du président du Conseil : 410 CAD par jour;. •. Pour le président du Conseil : 420 CAD par jour; b) Pour ce qui est de la préparation, la présence et la participation aux réunions des comités du. Conseil, les honoraires des gouverneurs doivent être versés selon des taux équivalant à ...

  2. Myanmar : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Programme: Governance and Justice ... La création de zones économiques frontalières constitue une importante stratégie d'industrialisation pour la Thaïlande et ouvre de nouvelles perspectives pour deux ... Una Hakika : Porter à grande échelle les solutions numériques pour la gestion des conflits au Kenya et en Birmanie.

  3. Tunisie : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Élaboration et essai pilote de modèles d'affaires pour obtenir des résultats à vaste échelle pour la transformation mécanisée des plantes fourragères. Projet. On retrouve en Afrique du Nord des écosystèmes marginaux, ainsi qu'une grande population rurale qui dépend sur des systèmes de cultures irriguées pour leur ...

  4. Publications | Page 195 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... a caractérisé un espace pastoral en utilisant une approche écologique. Il s''agit de la dendrométrie pour l''étude des peuplements ligneux et la méthode phytoécologique pour la végétation. Les... Plateforme participative d'information pour l'adaptation des communautés vulnérables aux changements climatiques : rapport ...

  5. Publications | Page 77 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La prévention et la gestion de la cryptosporidiose sont lourdes pour les hôpitaux et pour les vétérinaires. Il ressort de travaux de recherche soutenus par le CRDI sur les risques pour la santé présents dans les petites fermes laitières situées dans des régions urbaines pauvres du Kenya qu'il est plus dangereux de manger ...

  6. Publications | Page 79 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La prévention et la gestion de la cryptosporidiose sont lourdes pour les hôpitaux et pour les vétérinaires. Il ressort de travaux de recherche soutenus par le CRDI sur les risques pour la santé présents dans les petites fermes laitières situées dans des régions urbaines pauvres du Kenya qu'il est plus dangereux de manger ...

  7. Publications | Page 187 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La valeur de l'environnement – Faire appel à l'économie pour forger un avenir sous le signe de la durabilité. L'économie de l'environnement permet de déterminer les causes sous-jacentes des problèmes environnementaux et de trouver des solutions bénéfiques pour la population comme pour la planète. Depuis 1993, le ...

  8. Publications | Page 166 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La valeur de l'environnement – Faire appel à l'économie pour forger un avenir sous le signe de la durabilité. L'économie de l'environnement permet de déterminer les causes sous-jacentes des problèmes environnementaux et de trouver des solutions bénéfiques pour la population comme pour la planète. Depuis 1993, le ...

  9. Plaidoyer pour les oreilles | LAWSON | Journal de la Recherche ...

    African Journals Online (AJOL)

    Un counselling a été systématique prodigué comportant le principe de base et les 10 règles qui concourent à expliciter la proscription du coton-tige pour le nettoyage. Conclusion : Ce travail est un plaidoyer pour proscrire l'utilisation du coton-tige ou de tous autres instruments pour enlever le cérumen, ce qui est inutile, ...

  10. Toward rational design of amine solutions for PCC applications: the kinetics of the reaction of CO2(aq) with cyclic and secondary amines in aqueous solution.

    Science.gov (United States)

    Conway, William; Wang, Xiaoguang; Fernandes, Debra; Burns, Robert; Lawrance, Geoffrey; Puxty, Graeme; Maeder, Marcel

    2012-07-03

    The kinetics of the fast reversible carbamate formation reaction of CO(2)(aq) with a series of substituted cyclic secondary amines as well as the noncyclic secondary amine diethanolamine (DEA) has been investigated using the stopped-flow spectrophotometric technique at 25.0 °C. The kinetics of the slow parallel reversible reaction between HCO(3)(-) and amine has also been determined for a number of the amines by (1)H NMR spectroscopy at 25.0 °C. The rate of the reversible reactions and the equilibrium constants for the formation of carbamic acid/carbamate from the reactions of CO(2) and HCO(3)(-) with the amines are reported. In terms of the forward reaction of CO(2)(aq) with amine, the order with increasing rate constants is as follows: diethanolamine (DEA) < morpholine (MORP) ~ thiomorpholine (TMORP) < N-methylpiperazine (N-MPIPZ) < 4-piperidinemethanol (4-PIPDM) ~ piperidine (PIPD) < pyrrolidine (PYR). Both 2-piperidinemethanol (2-PIPDM) and 2-piperidineethanol (2-PIPDE) do not form carbamates. For the carbamate forming amines a Brønsted correlation relating the protonation constant of the amine to the carbamic acid formation rate and equilibrium constants at 25.0 °C has been established. The overall suitability of an amine for PCC in terms of kinetics and energy is discussed.

  11. The effect of pouring time on the dimensional stability of casts made from conventional and extended-pour irreversible hydrocolloids by 3D modelling

    Directory of Open Access Journals (Sweden)

    Hasan Ö. Gümüş

    2015-09-01

    Conclusion: All of the conventional and extended-pour impression materials tested in this study can be poured up to 24 hours with accuracy, if impressions are correctly stored. Extended-pour impression materials (ColorChange, Hydrogum 5, and Hydrocolor 5 can be poured up to 120 hours, if stored correctly.

  12. Separation of boron isotopes by aminated polystyrene-divinylbenzene resins

    International Nuclear Information System (INIS)

    Choi, Sei Young; Baek, Joong Hyun; Kim, Hee Lake

    1991-01-01

    Separation of boron isotopes was carried out by using nonporous aminated polystyrene-divinylbenzene as ion exchangers. After 0.1 M boric acid containing 10% sucrose solution was passed through the column, the boric acid band formed on the column was eluted with pure water of 50% methyl alchol water solution. The contents of boric acid of the fraction were determined with neutralization titrations. The relative mass of boron isotopes of the fractions was analyzed on a mass spectrometer. From these results, we found that separation factors for porous aminated polystyrene-divinylbenzene ion exchanger is larger than value of non porous ion exchanger, and then separation factors for 50%-methanol as eluting agent is larger than the value of pure water. (Author)

  13. Alpha-(trifluoromethyl)amine derivatives via nucleophilic trifluoromethylation of nitrones.

    Science.gov (United States)

    Nelson, D W; Owens, J; Hiraldo, D

    2001-04-20

    (Trifluoromethyl)trimethylsilane (TMSCF(3)) reacts with nitrones to afford alpha-(trifluoromethyl)hydroxylamines protected as O-trimethylsilyl ethers. Potassium t-butoxide initiates the nucleophilic trifluoromethylation. The reaction works best with alpha,N-diaryl nitrones, and the conditions are compatible with a range of substituents on the aryl groups. Acidic deprotection of the nitrone/TMSCF(3) adducts generates alpha-(trifluoromethyl)hydroxylamines. Catalytic hydrogenation of the adducts produces alpha-(trifluoromethyl)amines. Nitrone/TMSCF(3) adducts with strong electron-withdrawing groups on the alpha-aryl ring or heterocyclic alpha-aryl groups undergo an elimination/addition sequence to generate alpha,alpha-bis(trifluoromethyl)amines. Nitrones with alkyl groups bound directly to the 1,3-dipolar moiety fail to react with TMSCF(3), but trifluoromethylation of beta,gamma-unsaturated nitrones followed by reduction of the double bond can circumvent this limitation.

  14. Optimization of amine-terminated polyacrylonitrile synthesis and characterization

    Directory of Open Access Journals (Sweden)

    Mohamed H. El-Newehy

    2014-04-01

    Full Text Available Amine-terminated PANs were prepared in two steps. The first step includes free radical polymerization of acrylonitrile (AN using initiator pair of ammonium persulfate and sodium thiosulfate as redox system. In the second step, the amino groups were introduced through the reaction of polyacrylonitrile with excess of different diamines (10-fold including ethylenediamine (EDA, hexamethylenediamine (HMDA and octamethylenediamine (OMDA, to yield PAN–EDA, PAN–HMDA and PAN–OMDA, respectively. Optimization of the amine-terminated PANs synthesis was carried out at different temperatures (30–90 °C and different time intervals (4–24 h. In addition, the introduction of the amino group was followed by the piperidine test and recording of the FT-IR spectra. All polymers were characterized by, 1H NMR spectra, thermogravimetric analysis (TGA, and FT-IR spectra.

  15. Asymmetric trienamine catalysis: new opportunities in amine catalysis.

    Science.gov (United States)

    Kumar, Indresh; Ramaraju, Panduga; Mir, Nisar A

    2013-02-07

    Amine catalysis, through HOMO-activating enamine and LUMO-activating iminium-ion formation, is receiving increasing attention among other organocatalytic strategies, for the activation of unmodified carbonyl compounds. Particularly, the HOMO-raising activation concept has been applied to the greatest number of asymmetric transformations through enamine, dienamine, and SOMO-activation strategies. Recently, trienamine catalysis, an extension of amine catalysis, has emerged as a powerful tool for synthetic chemists with a novel activation strategy for polyenals/polyenones. In this review article, we discuss the initial developments of trienamine catalysis for highly asymmetric Diels-Alder reactions with different dienophiles and emerging opportunities for other types of cycloadditions and cascade reactions.

  16. AECL--Sulzer amine process for heavy water

    International Nuclear Information System (INIS)

    Wynn, N.P.

    1978-01-01

    A heavy water process based on isotopic exchange between hydrogen and methylamine and methylamine and water has been developed by Sulzer and Atomic Energy of Canada. Deuterium source is the synthesis gas stream of an ammonia plant. Deuterium enrichment is achieved by bithermal amine-hydrogen exchange; however, preliminary enrichment is made to occur in the reformers of the ammonia plant by using the steam reforming process as the decomposition step of a monothermal enrichment stage. This feature, coupled with the high value of the separation factor achievable with hydrogen-amine exchange, allows a high deuterium yield without the use of hydrogen recycle in the extraction stage. Design work has been based on pilot tests of the key process steps using industrial contacting equipment. 8 figures

  17. Debromination of endo-(+)-3-bromocamphor with primary amines

    Energy Technology Data Exchange (ETDEWEB)

    Markovic, Svetlana; Markovic, Violeta; Joksovic, Milan D.; Joksovic, Ljubinka, E-mail: ljubinka@kg.ac.rs [Department of Chemistry, Faculty of Science, University of Kragujevac (Serbia); Todorovic, Nina [Institute for Chemistry, Technology and Metallurgy, Belgrade (Serbia); Divjakovic, Vladimir [Department of Physics, University of Novi Sad (Serbia); Trifunovic, Snezana [Faculty of Chemistry, University of Belgrade, Belgrade, (Serbia)

    2013-07-15

    Reductive debromination of endo-(+)-3-bromocamphor with different primary amines followed by imine formation was investigated. This reaction requires simple experimental procedure without any organic solvent, metal or conventional reducing agent. A strong influence of amine polarity on the efficacy of debromination process was observed, and ethanolamine and ethylene diamine having sufficiently high boiling points can debrominate 3-bromocamphor giving corresponding camphanimines in good isolated yields. The mechanisms of debromination of 3-bromocamphor with ethanolamine and n-hexylamine were investigated at the B3LYP/6-311+G(d,p) level of theory. The radical mechanism was revealed, and it was shown that the reaction with more polar ethanolamine is energetically more favorable. (author)

  18. Praseodymium and neodymium separation by extraction with amines

    International Nuclear Information System (INIS)

    Benesova, M.; Kuca, L.; Sraier, V.

    1987-01-01

    Steady-state data were obtained for the separation of praseodymium and neodymium by extractions using different types of amines. The best is the system of a 30% solution of quaternary ammonium salt Aliquat 336 in xylene with a >3 M aqueous solution of NH 4 NO 3 where, at unit size of Pr and Nd partition ratios, the values of the Pr/Nd separation coefficient are within the region of 1.7 to 2.0. Pr cannot be separated from Nd by extraction with primary amine Primene-JMT from a sulfate medium. Separation factors in extraction with tri-n-octylamine have values of approx. 1.8 but the partition ratios of the two rare earth elements are less than 1. (author). 5 tabs., 5 refs

  19. Convenient Reductive Methylation of Amines with Carbonates at Room Temperature.

    Science.gov (United States)

    Li, Yuehui; Sorribes, Iván; Vicent, Cristian; Junge, Kathrin; Beller, Matthias

    2015-11-16

    Methylation of amines is a fundamental and commonly used reaction in organic synthesis. Many methods are known including various reductive methylations using formaldehyde, formic acid, or carbon dioxide in the presence of reductants. However, several of these methods suffer from limited substrate scope and chemoselectivity because of the different nucleophilicities of substrates. In this respect, the combination of carbonates and hydrosilanes is a valuable methylation source in the presence of Pt-based catalysts. This highly tunable method allows for methylation of both aromatic and aliphatic amines, and chemoselective methylation of aminoalcohols and diamines. Notably, the in situ-formed catalyst can also be used for the reduction of carbonates to methanol at room temperature. Mechanistic insights on intermediates formed during the reaction pathway were obtained by using ESI mass spectrometry. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Adsorption of catechol from aqueous solution by aminated hypercrosslinked polymers.

    Science.gov (United States)

    Sun, Yue; Li, Xiao-Tao; Xu, Chao; Chen, Jin-Long; Li, Ai-Min; Zhang, Quan-Xing

    2005-01-01

    Adsorption of catechol from aqueous solution with the hypercrosslinked polymeric adsorbent NDA-100 and its derivatives AH-1, AH-2 and AH-3 aminated by dimethylamine, the commercial resin Amberlite XAD-4 and weakly basic anion exchanger resin D301 was compared. It was found that the aminated hypercrosslinked resins had the highest adsorption capacities among the tested polymers. The empirical Freundlich equation was successfully employed to describe the adsorption process. Specific surface area and micropore structure of the adsorbent, in company with tertiary amino groups on matrix affected the adsorption performance towards catechol. In addition, thermodynamic study was carried out to interpret the adsorption mechanism. Kinetic study testified that the tertiary amino groups on the polymer matrix could decrease the adsorption rate and increase the adsorption apparent activation energy.

  1. Extraction of beryllium sulfate by a long chain amine

    International Nuclear Information System (INIS)

    Etaix, E.S.

    1968-01-01

    The extraction of sulfuric acid in aqueous solution by a primary amine in benzene solution, 3-9 (diethyl) - 6-amino tri-decane (D.E.T. ) - i.e., with American nomenclature 1-3 (ethyl-pentyl) - 4-ethyl-octyl amine (E.P.O.) - has made it possible to calculate the formation constants of alkyl-ammonium sulfate and acid sulfate. The formula of the beryllium and alkyl-ammonium sulfate complex formed in benzene has next been determined, for various initial acidity of the aqueous solution. Lastly, evidence has been given of negatively charged complexes of beryllium and sulfate in aqueous solution, through the dependence of the aqueous sulfate ions concentration upon beryllium extraction. The formation constant of these anionic complexes has been evaluated. (author) [fr

  2. Un logiciel pour la justice | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    28 oct. 2010 ... Evsys peut par ailleurs être adapté pour répondre aux besoins spécifiques d'un organisme. À LIRE ÉGALEMENT. HURIDOCS Site Web de Human Rights Information and DOCumentation Systems, International (HURIDOCS). HuriSearch. Moteur permettant de faire des recherches dans les sites Web de ...

  3. Amine enriched solid sorbents for carbon dioxide capture

    Science.gov (United States)

    Gray, McMahan L.; Soong, Yee; Champagne, Kenneth J.

    2003-04-15

    A new method for making low-cost CO.sub.2 sorbents that can be used in large-scale gas-solid processes. The new method entails treating a solid substrate with acid or base and simultaneous or subsequent treatment with a substituted amine salt. The method eliminates the need for organic solvents and polymeric materials for the preparation of CO.sub.2 capture systems.

  4. Electrophysiological effects of trace amines on mesencephalic dopaminergic neurons

    Directory of Open Access Journals (Sweden)

    Ada eLedonne

    2011-07-01

    Full Text Available Trace amines (TAs are a class of endogenous compounds strictly related to classic monoamine neurotransmitters with regard to their structure, metabolism and tissue distribution. Although the presence of TAs in mammalian brain has been recognized for decades, until recently they were considered to be by-products of amino acid metabolism or as ‘false’ neurotransmitters. The discovery in 2001 of a new family of G protein-coupled receptors (GPCRs, namely trace amines receptors, has re-ignited interest in TAs. In particular, two members of the family, trace amine receptor 1 (TA1 and trace amine receptor 2 (TA2, were shown to be highly sensitive to these endogenous compounds. Experimental evidence suggests that TAs modulate the activity of catecholaminergic neurons and that TA dysregulation may contribute to neuropsychiatric disorders, including schizophrenia, attention deficit hyperactivity disorder, depression and Parkinson’s disease, all of which are characterised by altered monoaminergic networks. Here we review recent data concerning the electrophysiological effects of TAs on the activity of mesencephalic dopaminergic neurons. In the context of recent data obtained with TA1 receptor knockout mice, we also discuss the mechanisms by which the activation of these receptors modulates the activity of these neurons. Three important new aspects of TAs action have recently emerged: (a inhibition of firing due to increased release of dopamine; (b reduction of D2 and GABAB receptor-mediated inhibitory responses (excitatory effects due to dysinhibition; and (c a direct TA1 receptor-mediated activation of GIRK channels which produce cell membrane hyperpolarization. While the first two effects have been well documented in our laboratory, the direct activation of GIRK channels by TA1 receptors has been reported by others, but has not been seen in our laboratory (Geracitano et al., 2004. Further research is needed to address this point, and to further

  5. Addition of amines to naphthoquinone in water and solid phase

    International Nuclear Information System (INIS)

    Martinez, Sabrina T.; Silva, Barbara V.; Pinto, Angelo C.; Ferreira, Vitor F.; Silva, Fernando de Carvalho da

    2012-01-01

    Considering all the aspects of the principles of green chemistry, we present herein the addition reactions of amines to 1,4-naphthoquinone in water as solvent and also in solid phase. These reactions resulted in very colorful products that were easily monitored by thin layer chromatography and consequently easy to separate. Therefore, they are interesting experiments for experimental organic chemistry in the classrooms or in the laboratories. (author)

  6. Amides derived from heteroaromatic amines and selected steryl hemiesters

    Czech Academy of Sciences Publication Activity Database

    Bildziukevich, Uladzimir; Rárová, L.; Šaman, David; Havlíček, Libor; Drašar, P.; Wimmer, Zdeněk

    2013-01-01

    Roč. 78, č. 14 (2013), s. 1347-1352 ISSN 0039-128X R&D Projects: GA ČR(CZ) GAP503/11/0616 Grant - others:GA MŠk(CZ) ED0007/01/01 Program:ED Institutional support: RVO:61389030 ; RVO:61388963 Keywords : Heteroaromatic amine * Cholesterol * Lanosterol Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 2.716, year: 2013

  7. Metabolism and genotoxicity of aromatic amines in aquatic organisms

    International Nuclear Information System (INIS)

    Knezovich, J.P.; Krauter, P.W.; Lawton, M.P.; Harrison, F.L.

    1987-01-01

    Marine mussels (Mytilus edulis) and bullfrog tadpoles (Rana catesbeiana) were used to investigate the comparative metabolism and genotoxicity of aromatic amines in vivo. These organisms were selected because they possess distinctly different metabolic capabilities: mussels lack an active mixed-function-oxidase enzyme system that is present in most other organisms, including amphibians. Using 14 C-labeled chemical probes (o- and p-toluidine, 2-aminofluorene (2-AF), and 2-acetylaminofluorene (2-AAF)), mussels and tadpoles well dosed with individual compounds by direct immersion in aqueous solutions. The identities of metabolites were then determined by HPLC and GC/MS methods. Results indicate that the N-conjugating pathways used by mussels result primarily in the detoxification of aromatic amines by limiting the amount of primary amine available for activation. The tadpoles excreted a number of 2-AAF metabolites but did form DNA and protein adducts in the liver. Induction of micronuclei in the peripheral red blood cells was also demonstrated. The tadpole was shown to be a sensitive biological indicator of pollution in aquatic ecosystems

  8. Changements climatiques | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    L'objectif du programme Changements climatiques consiste à appuyer des partenariats et des réseaux visant à rassembler des données probantes pour trouver des solutions et utiliser les technologies en vue d'obtenir des gains sociaux et économiques et d'atténuer les effets des changements climatiques pour l'avenir.

  9. Publications | Page 13 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Bien que la recherche a largement montré que les adolescents ont besoin de réseaux sociaux positifs et de connexions interpersonnelles – capital social positif – pour devenir des adultes productifs et socialement responsables, le capital social, son fonctionnement et le rôle essentiel qu'il joue pour diminuer la délinquance ...

  10. Rapports financiers trimestriels | CRDI - Centre de recherches pour ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Rapports financiers trimestriels. 2017. Rapport financier trimestriel pour le trimestre qui a pris fin le 30 septembre 2017 · Rapport financier trimestriel pour le trimestre qui a pris fin le 30 juin 2017 · Analyse de la direction et États financiers 2016–2017 ...

  11. Approximation point par point pour la resolution du probleme de ...

    African Journals Online (AJOL)

    Approximation point par point pour la resolution du probleme de dirichlet dans un disque pour l'equation elliptique du second ordre a coefficients constants dans le cas ou les racines de l'equation caracteristique sont distinctes. AMJ Tchalla, K Tcharie ...

  12. Villes durables intelligentes | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    6 juin 2016 ... Smart Cities for Sustainable Development. Elsa Estevez, Nuno Vasco Lopes et Tomasz Janowski. On prévoit que de 2014 à 2050, la population urbaine mondiale devrait croître de 63 pour cent, comparativement à une croissance de la population mondiale globale de 32 pour cent pendant la même ...

  13. Inde | Page 119 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    The death of the main breadwinner, a sick family member who requires medical attention, theft, a fire, or a flood—these misfortunes can wipe out a lifetime of hard work. Read more about Selling security to the poor. Langue English. En 1989, alors qu'il travaillait pour l'Organisation des Nations Unies pour l'agriculture et ...

  14. Livres | Page 31 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Management of Water Demand in Africa and the Middle East : Current Practices and Future Needs. Partout en Afrique et au Moyen-Orient, les réserves d'eau potable pour la culture et la transformation des aliments, les utilisations domestiques et urbaines et, ainsi que pour les activités indust. Directeur(s) : David B. Brooks, ...

  15. Publications | Page 125 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ÉTUDE DE CAS — Chili : Santé, environnement et culture autochtone. Un regain de vie pour les collectivités Mapuche. Les populations autochtones sont parmi les plus pauvres et les plus marginalisées de la planète. Ce sont elles aussi qui sont les plus tributaires, pour leur.

  16. Publications | Page 118 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La culture du pavot à opium : quelle politique pour l'Afghanistan ? La culture illicite du pavot à opium contribue à la subsistance de millions de paysans afghans, mais il se trouve qu'elle constitue également une source de revenus importants pour les bandes criminalisées.

  17. Publications | Page 24 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Cependant, il est couramment utilisé comme combustible, dans les régions rurales, pour faire cuire le pain dans un four traditionnel. Objectif du Vietnam : taille optimale pour les entreprises émergentes. La croissance impressionnante du Vietnam depuis les années 1990 lui a permis d'acquérir le statut de pays à revenu ...

  18. Publications | Page 162 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    africain. Il y a deux ans, le Centre de recherches pour le développement international a créé CIME, un programme de communication pour le développement, afin de témoigner de l'importance des interrelations entre la Communication à la base, l'.

  19. Publications | Page 101 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    L'action du CRDI L'adaptation aux changements climatiques. De nouvelles connaissances pour un avenir incertain. Bien avant que l'expression « réchauffement de la planète » ne fasse la manchette, le Centre de recherches pour le développement international (CRDI), organisme.

  20. Publications | Page 6 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Dans ce profil de 2014, les chercheurs du Tata Institute of Social Sciences Centre pour la politique urbaine et la gouvernance fournissent une base pour comprendre les nombreux visages de Mumbai et comment ses niveaux relativement bas de crime public masquent les nombreuses façons dont les résidents vivent la ...

  1. Equilibrium and Transport Properties of Primary, Secondary and Tertiary Amines by Molecular Simulation

    Directory of Open Access Journals (Sweden)

    Orozco Gustavo A.

    2014-09-01

    Full Text Available Using molecular simulation techniques such as Monte Carlo (MC and molecular dynamics (MD, we present several simulation results of thermodynamic and transport properties for primary, secondary and tertiary amines. These calculations are based on a recently proposed force field for amines that follows the Anisotropic United Atom approach (AUA. Different amine molecules have been studied, including n-ButylAmine, di-n-ButylAmine, tri-n-ButylAmine and 1,4-ButaneDiAmine for primary, secondary, tertiary and multi-functional amines respectively. For the transport properties, we have calculated the viscosity coefficients as a function of temperature using the isothermal-isobaric (NPT ensemble. In the case of the pure components, we have investigated different thermodynamic properties using NVT Gibbs ensemble simulations such as liquid-vapor phase equilibrium diagrams, vaporization enthalpies, vapor pressures, normal boiling points, critical temperatures and critical densities. We have also calculated the excess enthalpies for water-n-ButylAmine and n-heptane-n-ButylAmine mixtures using Monte Carlo simulations in the NPT ensemble. In addition, we present the calculation of liquid-vapor surface tensions of n-ButylAmine using a two-phase NVT simulation as well as the radial distribution functions. Finally, we have investigated the physical Henry constants of nitrous oxide (N2O and nitrogen (N2 in an aqueous solutions of n-ButylAmine. In general, we found a good agreement between the available experimental information and our simulation results for all the studied properties, ratifying the predictive capability of the AUA force field for amines.

  2. Identification of amines in wintertime ambient particulate material using high resolution aerosol mass spectrometry

    Science.gov (United States)

    Bottenus, Courtney L. H.; Massoli, Paola; Sueper, Donna; Canagaratna, Manjula R.; VanderSchelden, Graham; Jobson, B. Thomas; VanReken, Timothy M.

    2018-05-01

    Significant amounts of amines were detected in fine particulate matter (PM) during ambient wintertime conditions in Yakima, WA, using a high resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS). Positive matrix factorization (PMF) of the organic aerosol (OA) signal resulted in a six-factor solution that included two previously unreported amine OA factors. The contributions of the amine factors were strongly episodic, but the concentration of the combined amine factors was as high as 10-15 μg m-3 (2-min average) during those episodes. In one occasion, the Amine-II component was 45% of total OA signal. The Amine-I factor was dominated by spectral peaks at m/z 86 (C5H12N+) and m/z 100 (C6H14N+), while the Amine-II factor was dominated by spectral peaks at m/z 58 (C3H8N+ and C2H6N2+) and m/z 72 (C4H10N+ and C3H8N2+). The ions dominating each amine factor showed distinct time traces, suggesting different sources or formation processes. Investigation into the chemistry of the amine factors suggests a correlation with inorganic anions for Amine-I, but no evidence that the Amine-II was being neutralized by the same inorganic ions. We also excluded the presence of organonitrates (ON) in the OA. The presence of C2H4O2+ at m/z 60 (a levoglucosan fragment) in the Amine-I spectrum suggests some influence of biomass burning emissions (more specifically residential wood combustion) in this PMF factor, but wind direction suggested that the most likely sources of these amines were agricultural activities and feedlots to the S-SW of the site.

  3. Temperature-Dependent Henry's Law Constants of Atmospheric Amines.

    Science.gov (United States)

    Leng, Chunbo; Kish, J Duncan; Roberts, Jason E; Dwebi, Iman; Chon, Nara; Liu, Yong

    2015-08-20

    There has been growing interest in understanding atmospheric amines in the gas phase and their mass transfer to the aqueous phase because of their potential roles in cloud chemistry, secondary organic aerosol formation, and the fate of atmospheric organics. Temperature-dependent Henry's law constants (KH) of atmospheric amines, a key parameter in atmospheric chemical transport models to account for mass transfer, are mostly unavailable. In this work, we investigated gas-liquid equilibria of five prevalent atmospheric amines, namely 1-propylamine, di-n-propylamine, trimethylamine, allylamine, and 4-methylmorpholine using bubble column technique. We reported effective KH, intrinsic KH, and gas phase diffusion coefficients of these species over a range of temperatures relevant to the lower atmosphere for the first time. The measured KH at 298 K and enthalpy of solution for 1-propylamine, di-n-propylamine, trimethylamine, allylamine, and 4-methylmorpholine are 61.4 ± 4.9 mol L(-1) atm(-1) and -49.0 ± 4.8 kJ mol(-1); 14.5 ± 1.2 mol L(-1) atm(-1) and -72.5 ± 6.8 kJ mol(-1); 8.9 ± 0.7 mol L(-1) atm(-1) and -49.6 ± 4.7 kJ mol(-1); 103.5 ± 10.4 mol L(-1) atm(-1) and -42.7 ± 4.3 kJ mol(-1); and 952.2 ± 114.3 mol L(-1) atm(-1) and -82.7 ± 9.7 kJ mol(-1), respectively. In addition, we evaluated amines' characteristic times to achieve gas-liquid equilibrium for partitioning between gas and aqueous phases. Results show gas-liquid equilibrium can be rapidly established at natural cloud droplets surface, but the characteristic times may be extended substantially at lower temperatures and pHs. Moreover, our findings imply that atmospheric amines are more likely to exist in cloud droplets, and ambient temperature, water content, and pH of aerosols play important roles in their partitioning.

  4. From caffeine to fish waste: amine compounds present in food and drugs and their interactions with primary amine oxidase.

    LENUS (Irish Health Repository)

    Olivieri, Aldo

    2011-07-01

    Tissue bound primary amine oxidase (PrAO) and its circulating plasma-soluble form are involved, through their catalytic activity, in important cellular roles, including the adhesion of lymphocytes to endothelial cells during various inflammatory conditions, the regulation of cell growth and maturation, extracellular matrix deposition and maturation and glucose transport. PrAO catalyses the oxidative deamination of several xenobiotics and has been linked to vascular toxicity, due to the generation of cytotoxic aldehydes. In this study, a series of amines and aldehydes contained in food and drugs were tested via a high-throughput assay as potential substrates or inhibitors of bovine plasma PrAO. Although none of the compounds analyzed were found to be substrates for the enzyme, a series of molecules, including caffeine, the antidiabetics phenformin and tolbutamide and the antimicrobial pentamidine, were identified as PrAO inhibitors. Although the inhibition observed was in the millimolar and micromolar range, these data show that further work will be necessary to elucidate whether the interaction of ingested biogenic or xenobiotic amines with PrAO might adversely affect its biological roles.

  5. Sponges with covalently tethered amines for high-efficiency carbon capture

    KAUST Repository

    Qi, Genggeng

    2014-12-12

    © 2014 Macmillan Publishers Limited. All rights reserved. Adsorption using solid amine sorbents is an attractive emerging technology for energy-efficient carbon capture. Current syntheses for solid amine sorbents mainly based on physical impregnation or grafting-to methods (for example, aminosilane-grafting) lead to limited sorbent performance in terms of stability and working capacity, respectively. Here we report a family of solid amine sorbents using a grafting-from synthesis approach and synthesized by cationic polymerization of oxazolines on mesoporous silica. The sorbent with high amount of covalently tethered amines shows fast adsorption rate, high amine efficiency and sorbent capacity well exceeding the highest value reported to date for lowerature carbon dioxide sorbents under simulated flue gas conditions. The demonstrated efficiency of the new amine-immobilization chemistry may open up new avenues in the development of advanced carbon dioxide sorbents, as well as other nitrogen-functionalized systems.

  6. A one-pot chemoselective synthesis of secondary amines by using a biomimetic electrocatalytic system

    International Nuclear Information System (INIS)

    Largeron, Martine

    2009-01-01

    A one-pot electrochemically induced oxidation-imine formation-reduction route to secondary amines is described in detail. The key step of the process consists of the o-iminoquinone-mediated chemoselective catalytic oxidation of a primary aliphatic amine substrate, in the presence of a second amine used as the alkylating agent. Through the examination of the scope of the reaction by systematically varying both amine substrate and amine alkylating agent, it can be shown that this reaction sequence, leaving ammonia as the sole by-product, allows the rapid synthesis of various secondary amines in moderate to good yields. This process, that highlights the pre-eminent green advantages of electrochemical synthesis, especially the utilization of electricity as energy instead of chemical reagents, high atom economy as well as ambient temperature and pressure, could be a mild alternative to already reported synthetic methods.

  7. Direct α-C-H bond functionalization of unprotected cyclic amines

    Science.gov (United States)

    Chen, Weijie; Ma, Longle; Paul, Anirudra; Seidel, Daniel

    2018-02-01

    Cyclic amines are ubiquitous core structures of bioactive natural products and pharmaceutical drugs. Although the site-selective abstraction of C-H bonds is an attractive strategy for preparing valuable functionalized amines from their readily available parent heterocycles, this approach has largely been limited to substrates that require protection of the amine nitrogen atom. In addition, most methods rely on transition metals and are incompatible with the presence of amine N-H bonds. Here we introduce a protecting-group-free approach for the α-functionalization of cyclic secondary amines. An operationally simple one-pot procedure generates products via a process that involves intermolecular hydride transfer to generate an imine intermediate that is subsequently captured by a nucleophile, such as an alkyl or aryl lithium compound. Reactions are regioselective and stereospecific and enable the rapid preparation of bioactive amines, as exemplified by the facile synthesis of anabasine and (-)-solenopsin A.

  8. Potentiel des images satellitaires multibandes a haute resolution spatiale pour la cartographie des componsants de l'eau en milieu cotier marin

    Science.gov (United States)

    Lavoie, Andre

    L'objectif principal que que nous poursuivons est de developper un modele de simulation du transfert radiatif eau-atmosphere adapte aux observations faites par le capteur Thematic Mapper (TM) de Landsat. Les informations que nous cherchons ont trait au milieu cotier marin et concernent les elements qui sont en suspension dans l'eau. Les images multibandes du capteur TM dans la partie visible du spectre, sont surtout visees par nos travaux. A la base de la simulation, nous utilisons un programme de simulation atmospherique, le code 6S, auquel nous greffons un modele de simulation du transfert radiatif dans la masse d'eau. Ce dernier estime le signal en fonction de 4 composants: l'eau, les pigments chlorophylliens (chlorophylle et phaeopigments), les matieres minerales et les substances organiques dissoutes. La concentration des differents composants sert de parametre d'entree pour definir le comportement optique de la masse d'eau. Le modele permet egalement de simuler une masse d'eau stratifiee si l'on connai t les concentrations des composants dans les differentes couches. Il inclut aussi la contribution du fond, selon sa nature et sa composition, ainsi que celle du miroitement du soleil et du ciel a la surface de l'eau. Les informations d'un echantillonnage de la masse d' eau synchronise avec le passage du satellite, a la baie des Chaleurs, d'une cartographie du couvert d'algues et d'un modele bathymetrique ont ete utilisees pour fixer les parametres de simulation par le modele. La comparaison montrent que le modele se comporte relativement bien surtout dans la bande TM2. Une erreur systematique de 2 valeurs numeriques en moyenne subsiste dans les trois bandes spectrales. Les resultats nous montrent que la visibilite du fond aux faibles profondeurs est un element tres important a considerer. Par ailleurs, l'analyse de sensibilite montre que les images TM sont plus sensibles aux concentrations en matieres minerales qu'aux pigments chlorophylliens et aux substances

  9. Amines in the marking fluid and anal sac secretion of the tiger, Panthera tigris.

    Science.gov (United States)

    Banks, G R; Buglass, A J; Waterhouse, J S

    1992-01-01

    Analysis of the marking fluid of two tigers (one Bengal and one Sumatran) by GC using an amine-specific column and a nitrogen-specific detector has shown the presence of the following amines: ammonia, methylamine, dimethylamine, trimethylamine, triethylamine, propylamine, and butane-1,4-diamine (putrescine). In contrast to previously published reports, we were unable to detect 2-phenylethylamine. The anal sac secretion was found to have a similar amine content.

  10. Synthesis of propargylic and allenic carbamates via the C-H amination of alkynes.

    Science.gov (United States)

    Grigg, R David; Rigoli, Jared W; Pearce, Simon D; Schomaker, Jennifer M

    2012-01-06

    Propargylic amines are important intermediates for the synthesis of nitrogen-containing heterocycles. The insertion of a nitrene into a propargylic C-H bond has not been explored, despite the attention directed toward the Rh-catalyzed amination of other types of C-H bonds. In this communication, the conversion of a series of homopropargylic carbamates to propargylic carbamates and aminated allenes is described. © 2011 American Chemical Society

  11. Cross-Linking Amine-Rich Compounds into High Performing Selective CO2 Absorbents

    OpenAIRE

    Andreoli, Enrico; Dillon, Eoghan P.; Cullum, Laurie; Alemany, Lawrence B.; Barron, Andrew R.

    2014-01-01

    Amine-based absorbents play a central role in CO2 sequestration and utilization. Amines react selectively with CO2, but a drawback is the unproductive weight of solvent or support in the absorbent. Efforts have focused on metal organic frameworks (MOFs) reaching extremely high CO2 capacity, but limited selectivity to N2 and CH4, and decreased uptake at higher temperatures. A desirable system would have selectivity (cf. amine) and high capacity (cf. MOF), but also increased adsorption at highe...

  12. Nickel-Catalyzed Amination of Aryl Sulfamates and Carbamates Using an Air-Stable Precatalyst

    Science.gov (United States)

    Hie, Liana; Ramgren, Stephen D.; Mesganaw, Tehetena; Garg, Neil K.

    2012-01-01

    A facile nickel-catalyzed method to achieve the amination of synthetically useful aryl sulfamates and carbamates is reported. Contrary to most Ni-catalyzed amination reactions, this user-friendly approach relies on an air-stable Ni(II) precatalyst, which, when employed with a mild reducing agent, efficiently delivers aminated products in good to excellent yields. The scope of the method is broad with respect to both coupling partners and includes heterocyclic substrates. PMID:22849697

  13. Laboratory evaluation of borate/amine/zinc formulations for fungal decay protection

    Science.gov (United States)

    George C. Chen; Rebecca E. Ibach

    2010-01-01

    The goals of this study were to evaluate borate/amine/zinc formulations in wood for fungal decay protection as well as the permanence of zinc and boron in wood. Wood treated with each of four formulations of borate/amine/zinc prevented or decreased fungal degradation after a 12-week AWPA Standard soil-block test. For non-leached specimens, wood treated with borax/amine...

  14. The toxicity of MEA and amine waste water samples using standardised freshwater bioassays

    OpenAIRE

    Brooks, S.; Heiaas, H.; Lillicrap, A.

    2013-01-01

    Water samples provided by Tel-Tek AS were assessed for their toxicity to freshwater organisms from three trophic groups. The water samples included pure monoethanolamine (MEA) and two amine waste water mixtures described as Amine Reactor Waste (ARW) and treated amine waste water (TW). The toxicity of these three test solutions to the unicellular algae Pseudokirchneriella subcapitata, the freshwater crustacean Daphnia magna, and the embryos of the zebra fish Danio rerio were performed in accor...

  15. Ligand-exchange chromatography of aromatic amines on resin-bound cobalt ion

    Energy Technology Data Exchange (ETDEWEB)

    Pehlivan, E.; Vural, U.S.; Ayar, A.; Yildiz, S. [Selcuk Univ., Konya (Turkey)

    1996-06-01

    The use of cobalt metal for the selective separation of aromatic amines is completed with a chemically bonded diamine and glyoxime functional groups onto Lycopodium clavatum. Oximes and amines are excellent complexing agents for transition metal ions. Cobalt(II) metal ions can easily be immobilized on bis-diaminoethyl-glyoximated sporopollenin (bDAEG-sporopollenin). The ligand-exchange behavior of modified Lycopodium clavatum with respect to aromatic amines was investigated. This will permit the evaluation of bDAEG-sporopollenin ligand exchangers for their utilization as sorbents in the recovery, pollution control, and elimination of amines from wastewater.

  16. Targeting polyamines and biogenic amines by green tea epigallocatechin-3-gallate.

    Science.gov (United States)

    Melgarejo, Esther; Urdiales, José Luis; Sánchez-Jiménez, Francisca; Medina, Miguel Angel

    2010-02-01

    Biogenic amines and polyamines are organic polycations derived from aromatic or cationic amino acids. They exert pleiotropic effects, more related to intercellular communication in the case of biogenic amines, and to intracellular signaling in the case of polyamines. The bioactive compound epigallocatechin-3-gallate (EGCG), a major component of green tea, has been shown to target key enzyme of biogenic amine and polyamine metabolic pathways. Herein, we review the specific effects of EGCG on concrete molecular targets of both biogenic amine and polyamine metabolic pathways, and discuss the relevance of these data to support the potential therapeutic interest of this compound.

  17. Control of Biogenic Amines in Fermented Sausages: Role of Starter Cultures

    Science.gov (United States)

    Latorre-Moratalla, M.L.; Bover-Cid, Sara; Veciana-Nogués, M.T.; Vidal-Carou, M.C.

    2012-01-01

    Biogenic amines show biological activity and exert undesirable physiological effects when absorbed at high concentrations. Biogenic amines are mainly formed by microbial decarboxylation of amino acids and thus are usually present in a wide range of foods, fermented sausages being one of the major biogenic amine sources. The use of selected starter cultures is one of the best technological measures to control aminogenesis during meat fermentation. Although with variable effectiveness, several works show the ability of some starters to render biogenic amine-free sausages. In this paper, the effect of different starter culture is reviewed and the factors determining their performance discussed. PMID:22586423

  18. Control of biogenic amines in fermented sausages: role of starter cultures

    Directory of Open Access Journals (Sweden)

    Mariluz eLatorre-Moratalla

    2012-05-01

    Full Text Available Biogenic amines show biological activity and exert undesirable physiological effects when absorbed at high concentrations. Biogenic amines are mainly formed by microbial decarboxylation of amino acids and thus are usually present in a wide range of foods, fermented sausages being one of the major biogenic amine sources. The use of selected starter cultures is one of the best technological measures to control aminogenesis during meat fermentation. Although with variable effectiveness, several works show the ability of some starters to render biogenic amine-free sausages. In this paper, the effect of different starter culture is reviewed and the factors determining their performance discussed.

  19. Ligand-Enabled γ-C(sp(3))-H Olefination of Amines: En Route to Pyrrolidines.

    Science.gov (United States)

    Jiang, Heng; He, Jian; Liu, Tao; Yu, Jin-Quan

    2016-02-17

    Pd(II)-catalyzed olefination of γ-C(sp(3))-H bonds of triflyl (Tf) and 4-nitrobenzenesulfonyl (Ns) protected amines is achieved. Subsequent aza-Wacker oxidative cyclization or conjugate addition of the olefinated intermediates provides a variety of C-2 alkylated pyrrolidines. Three pyridine- and quinoline-based ligands are developed to match different classes of amine substrates, demonstrating a rare example of ligand-enabled C(sp(3))-H olefination reactions. The use of Ns protecting group to direct C(sp(3))-H activation of alkyl amines is also a significant step toward practical C-H functionalizations of alkyl amines.

  20. Chemical and Molecular Descriptors for the Reactivity of Amines with CO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Anita S.; Kitchin, John R.

    2012-10-24

    Amine-based solvents are likely to play an important role in CO{sub 2} capture applications in the future, and the identification of amines with superior performance will facilitate their use in CO{sub 2} capture. While some improvements in performance will be achieved through process modifications, modifying the CO{sub 2} capture performance of an amine also implies in part an ability to modify the reactions between the amine and CO{sub 2} through development of new functionalized amines. We present a computational study of trends in the reactions between CO{sub 2} and functionalized amines with a focus on identifying molecular descriptors that determine trends in reactivity. We examine the formation of bicarbonate and carbamate species on three classes of functionalized amines: alkylamines, alkanolamines, and fluorinated alkylamines including primary, secondary and tertiary amines in each class. These functional groups span electron-withdrawing to donating behavior, hydrogen-bonding, extent of functionalization, and proximity effects of the functional groups. Electron withdrawing groups tend to destabilize CO{sub 2} reaction products, whereas electron-donating groups tend to stabilize CO{sub 2} reaction products. Hydrogen bonding stabilizes CO{sub 2} reaction products. Electronic structure descriptors based on electronegativity were found to describe trends in the bicarbonate formation energy. A chemical correlation was observed between the carbamate formation energy and the carbamic acid formation energy. The local softness on the reacting N in the amine was found to partially explain trends carbamic acid formation energy.

  1. Synthesis of substituted propargylamines from aminals and phenylacetylen in the presence of Cu(I) halides

    Energy Technology Data Exchange (ETDEWEB)

    Komissarov, V.N.; Ukhin, L.Yu.; Orlova, Zh.I.; Tokarskaya, O.A.

    1987-11-20

    Aminals, the condensation products of carbonyl compounds with secondary amines (1), have been examined within a general scheme for the Mannich reaction (2), as precursors of iminium ions. The authors investigated the behavior of aminals derived from aromatic aldehydes upon heating with phenylacetylene and CuX (X = I, Br, Cl) in acetonitrile. The authors assumed that an aminal, acting as an HX acceptor, would lead to the formation of copper phenylacetylide, and be itself converted via this process to an iminium salt, which could then participate in an aminomethylation reaction of copper phenylacetylide. It was found that propargylamines were formed rapidly upon heating stoichiometric amounts of the reagents in acetonitrile solution.

  2. Method of neutralizing the corrosive surface of amine-cured epoxy resins

    Science.gov (United States)

    Lee, S. Y. (Inventor)

    1982-01-01

    The corrosive alkaline surface layer of an epoxy resin product formed by the curing of the epoxy with an aliphatic amine is eliminated by first applying a non-solvent to remove most or all of the free unreacted amine and then applying a layer of a chemical reagent to neutralize the unused amine or amine functional groups by forming a substituted urea. The surface then may be rinsed with acetone and then with alcohol. The non-solvent may be an alcohol. The neutralizing chemical reagent is a mono-isocyanate or a mono-isothiocyanate. Preferred is an aromatic mono-isocyanate such as phenyl isocyanate, nitrophenyl isocyanate and naplthyl isocyanate.

  3. De meilleurs emplois pour l'Asie | CRDI - Centre de recherches pour ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2 mars 2018 ... D'est en ouest, les économies de l'Asie se transforment rapidement, créant des emplois pour une population croissante de jeunes travailleurs. Cependant, qu'en est-il des conditions de travail ? Une recherche financée par le CRDI recueille des données probantes qui démontrent que de meilleures ...

  4. Synthesis and antimicrobial activity of styryl/pyrrolyl/pyrazolyl sulfonylmethyl-1,3,4-oxadiazolyl amines and styryl/pyrrolyl/pyrazolyl sulfonylmethyl-1,3,4-thiadiazolyl amines.

    Science.gov (United States)

    Sravya, G; Yamini, G; Padmavathi, V; Padmaja, A

    2016-10-21

    A new class of mono and bis heterocycles - styryl sulfonylmethyl-1,3,4-oxadiazolyl/1,3,4-thiadiazolyl amines, pyrrolyl sulfonylmethyl-1,3,4-oxadiazolyl/1,3,4-thiadiazolyl amines and pyrazolyl sulfonylmethyl-1,3,4-oxadiazolyl/1,3,4-thiadiazolyl amines were prepared from the synthetic intermediate Z-styrylsulfonylacetic acid adopting simple and well versed synthetic methodologies and studied their antimicrobial activity. Amongst all the tested compounds styryl thiadiazole 5c exhibited promising antimicrobial activity against Pseudomonas aeruginosa and Penicillium chrysogenum. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  5. Continuous temperature measurements on the pouring stand for casting moulds

    Directory of Open Access Journals (Sweden)

    W. Leśniewski

    2008-04-01

    Full Text Available The results of temperature measurements of liquid iron alloys obtained by means of the pyrometer, PDR-1800 series, are presented in the paper. The measurements were performed in conditions determined by the kind of a pouring device. The results obtained for bottom-tap ladles were supplemented by laboratory measurements. These results allow explaining significant differences in the results of temperature measurements performed in pouring ladles by means of the pyrometric method and immersible thermocouple, which - in turn - improves assessment of metal thermal parameters in pouring devices.

  6. Theoretical study on perylene derivatives as fluorescent sensors for amines

    Science.gov (United States)

    Lathiotakis, Nektarios N.; Kerkines, Ioannis S. K.; Theodorakopoulos, Giannoula; Petsalakis, Ioannis D.

    2018-01-01

    A theoretical study is presented on perylene diimide (PDI) and perylene monoimide (PMI) and their action as sensors of amines in solution. Density functional theory (DFT) and Time dependent DFT (TDDFT) calculations are carried out on complexes of PDI and PMI with aniline in THF solution. The optimized geometries for the complexes have aniline lying parallel above the perylene at 3.15 Å and with binding energy of 0.53 eV in the ground state. The results on the excited states are consistent with a photoinduced electron transfer (PET) mechanism. The effective aniline-perylene distance resulting from a Mulliken's approach is 3.61 Å.

  7. Economic Considerations for Selecting an Amine Donor in Biocatalytic Transamination

    DEFF Research Database (Denmark)

    Tufvesson, Pär; Nordblad, Mathias; Krühne, Ulrich

    2015-01-01

    the process, in particular the choice of amine donor. This paper discusses these constraints and demonstrates, through simple thermodynamic and economic models, the process targets that need to be set and achieved for a process dependent on allowed process costs and quality targets....... in industry. The technology has been demonstrated in a few selected cases, but widespread implementation and for a broader range of target molecules requires a deeper understanding of the underlying thermodynamic as well as economic constraints for the different choices that can be made in designing...

  8. Binary VLE measurements and modeling for selected amine systems

    OpenAIRE

    Saleem, Fahad

    2011-01-01

    During the course of this work, vapor pressure data of pure water, DEEA and DIPEA was measured. The results give good agreement with literature data. VLE data of DEEA-H2O and DIPEA-H2O systems was then obtained at varying concentration and temperature (50-95oC) range. Experimental activity coefficients were calculated using this VLE data. Moreover, FTIR spectroscopy in conjunction with ?The Unscrambler? was used for amine analyses of the experimental samples and results were compared with ...

  9. Processing method for drained water containing ethanol amine

    International Nuclear Information System (INIS)

    Wakuta, Kuniharu; Ogawa, Naoki; Sagawa, Hiroshi; Kamiyoshi, Hideki; Fukunaga, Kazuo; Iwamoto, Ken; Miki, Tsuyoshi; Hirata, Toshio

    1998-01-01

    Drained water containing ethanol amine is processed with microorganisms such as hydrazine resistant denitrification bacteria in a biodegrading vessel (A) in the coexistence of nitrous ions and/or nitric ions under an anaerobic condition, and then it is processed with microorganisms such as nitrification bacteria in another biotic oxidation vessel (B) under an aerobic condition to generate the coexistent nitrate ion and/or nitric ion, and returned to the biodegrading vessel (A). Further, they are exposed to air or incorporated with an oxidant and optionally a copper compound such as copper sulfate as a catalyst is added in a step of removing hydrazine. (T.M.)

  10. Synthesis of 2-aminoBODIPYs by palladium catalysed amination.

    Science.gov (United States)

    Alnoman, Rua B; Stachelek, Patrycja; Knight, Julian G; Harriman, Anthony; Waddell, Paul G

    2017-09-20

    Palladium catalysed coupling of the 2-iodoBODIPY 3 with a range of anilines and a primary alkylamine succeeds in generating the corresponding 2-aminoBODIPYs. These 2-aminoBODIPY derivatives are non-emissive and quantum chemical calculations and electrochemistry are consistent with charge transfer from the amine substituent. Attenuation of this charge transfer pathway by conversion of the 1,2-phenylenediamine derivative 9 into the corresponding benzimidazolone 10 restores the fluorescence and has been used as the basis for a fluorescence sensor for phosgene.

  11. Carbon nanomaterial based electrochemical sensors for biogenic amines

    International Nuclear Information System (INIS)

    Yang, Xiao; He, Xiulan; Li, Fangping; Fei, Junjie; Feng, Bo; Ding, Yonglan

    2013-01-01

    This review describes recent advances in the use of carbon nanomaterials for electroanalytical detection of biogenic amines (BAs). It starts with a short introduction into carbon nanomaterials such as carbon nanotubes, graphene, nanodiamonds, carbon nanofibers, fullerenes, and their composites. Next, electrochemical sensing schemes are discussed for various BAs including dopamine, serotonin, epinephrine, norepinephrine, tyramine, histamine and putrescine. Examples are then given for methods for simultaneous detection of various BAs. Finally, we discuss the current and future challenges of carbon nanomaterial-based electrochemical sensors for BAs. The review contains 175 references. (author)

  12. Hardness of restorative resins: effect of camphorquinone, amine, and inhibitor.

    Science.gov (United States)

    Peutzfeldt, A; Asmussen, E

    1989-08-01

    The influence of the content of camphorquinone (CQ), amine (DABE), and inhibitor (MHQ) on the Wallace indentation hardness of light-curing polymers was investigated. The hardness was measured on disc-shaped specimens made from 50 bisphenol-A-glycidyl-dimethacrylate/triethyleneglycol-dimethacryla te-based monomers with various contents of CQ, DABE, and MHQ. When no MHQ had been added, the hardness number decreased with increasing content of CQ. This was also the case with increasing content of DABE, but to a lesser extent. In the presence of MHQ, the contents of CQ and DABE did not influence the hardness number significantly.

  13. Phenols and aromatic amines as thermal stabilizers in polyolefin processing

    Czech Academy of Sciences Publication Activity Database

    Pospíšil, Jan; Habicher, W. D.; Al-Malaika, S.; Zweifel, H.; Nešpůrek, Stanislav

    2001-01-01

    Roč. 176, - (2001), s. 55-63 ISSN 1022-1360. [International Conference on Polymer Modification, Degradation and Stabilization /1./. Palermo, 03.09.2000-07.09.2000] R&D Projects: GA AV ČR IAA1050901; GA MŠk ME 184; GA MŠk ME 372; GA AV ČR KSK4050111 Institutional research plan: CEZ:AV0Z4050913 Keywords : thermal stabilizers * phenols * aromatic amines Subject RIV: CD - Macromolecular Chemistry Impact factor: 0.634, year: 2001

  14. Pulmonary extraction of biogenic amines during septic shock

    International Nuclear Information System (INIS)

    Kerstein, M.D.; Kohler, J.; Gould, S.; Moseley, P.

    1982-01-01

    The effect of live Escherichia coli on the pulmonary extraction of the biogenic amines 14 C 5-hydroxytryptamine, (5-HT) and 3 H-epinephrine was investigated. The labeled isotopes were injected into a central venous catheter and collected from an aortic catheter. One hundred per cent of the labeled epinephrine was recovered in the control and septic state. Only 32.8 +/- 3.6% SEM of the 5-hydroxytryptamine was recovered before sepsis and 42.5 +/- 4.9% SEM after sepsis. During sepsis, mean arterial pressure fell to 58 mm Hg from 121 mm Hg. Pulmonary shunt increased from .7 +/- .05 SEM to .33 +/- .09 SEM

  15. Extraction and purification of plutonium by a tertiary amine

    International Nuclear Information System (INIS)

    Trentinian, M. de; Chesne, A.; Commissariat a l'Energie Atomique, Saclay

    1960-01-01

    Trilaurylamine diluted with a paraffinic solvent (dodecane) was studied as part of the research dealing with the separation and purification of plutonium. The physical properties (solubility of nitrates in the amine as a function of temperature) and the resistance to radiations of this substance were examined. The extraction characteristics of nitric solutions of plutonium, uranium and certain fission products are given as a function of the following factors: concentration of the various ions in solution, valency states. A method of plutonium purification based on these results is presented. (author) [fr

  16. Data Center: infrastructure pour la ville

    OpenAIRE

    Sachs, Mikaël

    2016-01-01

    A l'aube d'une génération 100 % numérique, notre production, notre consommation ainsi que le traitement de nos données digitales augmentent de façon exponentielle. Le data center, milieu tempéré et sécurisé pour les machines, est le cœur de cette nouvelle ère. L'information dématérialisée nécessite une infrastructure précise et complexe. Gardien des cultures mouvantes et insaisissables, le data center peut être perçu comme un univers public parallèle à la ville, son insertion dans le milieu u...

  17. Suivi de route pour un robot voilier

    OpenAIRE

    Jaulin, Luc; Le Bars, Fabrice; Clement, Benoît; Gallou, Yvon; Menage, Olivier; REYNET, Olivier; Sliwka, Jan; Zerr, Benoît

    2012-01-01

    International audience; Un robot voilier est un système fortement nonlinéaire qui pourtant se commande relativement facilement. En effet, sa conception mécanique découle d'une évolution pragmatique sur plusieurs milliers d'années avec pour double objectif : celui d'une machine rapide et celui d'avoir un véhicule facile à commander. Cet article propose une stratégie de régulation d'un robot voilier inspirée de celle utilisée par les navigateurs. Le régulateur qui en résulte est simple, avec pe...

  18. A lunguistica pour ses quarante ans

    Directory of Open Access Journals (Sweden)

    Ludvik Horvat Le Doyen

    2000-12-01

    Full Text Available En tant que doyen de la Faculté des Lettres de l'Universite de Ljubljana, j'ai l'honneur d'introduire le volume qui celebre les quarante ans de publication de cette revue linguistique. La parution de la revue conçua à l' origine comme supplàment pour la linguistique non slave de la revue Slavistična revija (dont la renommée était déjà affirmée, eut lieu en 1958. Ses inspirateurs, ses fondateurs et ses premiers directeurs, auxquels nous gardons une profonde reconnaissance, furent l'italianiste Stanko Škerlj et le latiniste Milan Grošelj, professeurs de notre Faculté. Des sa quatrieme année ce modeste supplement devint revue autonome, telle que nous la connaissons aujourd'hui.

  19. Évaluation organisationnelle | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    évaluation. Charles Lusthaus, Marie-Hélène Adrien, Gary Anderson et Fred Carden (CRDI 1999). ÉVALUATION INSTITUTIONNELLE: Cadre pour le renforcement des organisations partenaires du CRDI. Charles Lusthaus, Gary ...

  20. Modelisation des effets physico-techniques pour la conception des ...

    African Journals Online (AJOL)

    automatisation dans les installations industrielles a besoin d'une régulation automatique des commandes des processus technologiques pour lesquelles certaines contraintes sont à relever compte tenu des exigences des innovations scientifiques de ...

  1. Inde | Page 80 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    FOOD India), a commencé à se demander comment faire pour mettre les ... experimentation, and research related to information and communication technologies for development (ICTs), employment generation, and other aspects of sustainable.

  2. Analysis of irradiated biogenic amines by computational chemistry and spectroscopy

    International Nuclear Information System (INIS)

    Oliveira, Jorge L.S.P.; Borges Junior, Itamar; Cardozo, Monique; Souza, Stefania P.; Lima, Antonio L.S.; Lima, Keila S.C.

    2011-01-01

    Biogenic Amines (B A) are nitrogenous compounds able to cause food poisoning. In this work, we studied the tyramine, one of the most common BA present in foods by combining experimental measured IR (Infrared) and GC/MS (Gas Chromatograph / Mass Spectrometry) spectra and computational quantum chemistry. Density Functional Theory (DFT) and the Deformed Atoms in Molecules (DMA) method was used to compute the partition the electronic densities in a chemically-intuitive way and electrostatic potentials of molecule to identify the acid and basic sites. Trading pattern was irradiated using a Cs 137 radiator, and each sample was identified by IR and GC/MS. Calculated and experimental IR spectra were compared. We observed that ionizing gamma irradiation was very effective in decreasing the population of standard amine, resulting in fragments that could be rationalized through the quantum chemistry calculations. In particular, we could locate the acid and basic sites of both molecules and identify possible sites of structural weaknesses, which allowed to propose mechanistic schemes for the breaking of chemical bonds by the irradiation. Moreover, from this work we hope it will be also possible to properly choose the dose of gamma irradiation which should be provided to eliminate each type of contamination. (author)

  3. Switchable regioselectivity in amine-catalysed asymmetric cycloadditions

    Science.gov (United States)

    Zhou, Zhi; Wang, Zhou-Xiang; Zhou, Yuan-Chun; Xiao, Wei; Ouyang, Qin; Du, Wei; Chen, Ying-Chun

    2017-06-01

    Building small-molecule libraries with structural and stereogenic diversity plays an important role in drug discovery. The development of switchable intermolecular cycloaddition reactions from identical substrates in different regioselective fashions would provide an attractive protocol. However, this also represents a challenge in organic chemistry, because it is difficult to control regioselectivity to afford the products exclusively and at the same time achieve high levels of stereoselectivity. Here, we report the diversified cycloadditions of α‧-alkylidene-2-cyclopentenones catalysed by cinchona-derived primary amines. An asymmetric γ,β‧-regioselective intermolecular [6+2] cycloaddition reaction with 3-olefinic (7-aza)oxindoles is realized through the in situ generation of formal 4-aminofulvenes, while a different β,γ-regioselective [2+2] cycloaddition reaction with maleimides to access fused cyclobutanes is disclosed. In contrast, an intriguing α,γ-regioselective [4+2] cycloaddition reaction is uncovered with the same set of substrates, by employing an unprecedented dual small-molecule catalysis of amines and thiols. All of the cycloaddition reactions exhibit excellent regio- and stereoselectivity, producing a broad spectrum of chiral architectures with high structural diversity and molecular complexity.

  4. Palladium-catalysed anti-Markovnikov selective oxidative amination

    Science.gov (United States)

    Kohler, Daniel G.; Gockel, Samuel N.; Kennemur, Jennifer L.; Waller, Peter J.; Hull, Kami L.

    2018-03-01

    In recent years, the synthesis of amines and other nitrogen-containing motifs has been a major area of research in organic chemistry because they are widely represented in biologically active molecules. Current strategies rely on a multistep approach and require one reactant to be activated prior to the carbon-nitrogen bond formation. This leads to a reaction inefficiency and functional group intolerance. As such, a general approach to the synthesis of nitrogen-containing compounds from readily available and benign starting materials is highly desirable. Here we present a palladium-catalysed oxidative amination reaction in which the addition of the nitrogen occurs at the less-substituted carbon of a double bond, in what is known as anti-Markovnikov selectivity. Alkenes are shown to react with imides in the presence of a palladate catalyst to generate the terminal imide through trans-aminopalladation. Subsequently, olefin isomerization occurs to afford the thermodynamically favoured products. Both the scope of the transformation and mechanistic investigations are reported.

  5. Technological factors affecting biogenic amine content in foods: a review

    Directory of Open Access Journals (Sweden)

    Fausto Gardini

    2016-08-01

    Full Text Available Biogenic amines (BAs are molecules which can be present in foods and, due to their toxicity, can cause adverse effects on the consumers. BAs are generally produced by microbial decarboxylation of amino acids in food products. The most significant BAs occurring in foods are histamine, tyramine, putrescine, cadaverine, tryptamine, 2-phenylethylamine, spermine, spermidine and agmatine. The importance of preventing the excessive accumulation of BAs in food is related to their impact on human health and food quality. Quality criteria in connection with the presence of BAs in food and food products are necessary from a toxicological point of view. This is particularly important in fermented foods in which the massive microbial proliferation required for obtaining specific products is often relater with BA accumulation. In this review, up-to-date information and recent discoveries about technological factors affecting biogenic amine content in foods are reviewed. Specifically, BA forming-microorganism and decarboxylation activity, genetic and metabolic organization of decarboxylases, risk associated to BAs (histamine, tyramine toxicity and other BAs, environmental factors influencing BA formation (temperature, salt concentration, pH. In addition, the technological factors for controlling BA production (use of starter culture, technological additives, effects of packaging, other non-thermal treatments, metabolising BA by microorganisms, effects of pressure treatments on BA formation and antimicrobial substances are addressed.

  6. Reduction of amine N-oxides by diboron reagents.

    Science.gov (United States)

    Kokatla, Hari Prasad; Thomson, Paul F; Bae, Suyeal; Doddi, Venkata Ramana; Lakshman, Mahesh K

    2011-10-07

    Facile reduction of alkylamino-, anilino-, and pyridyl-N-oxides can be achieved via the use of diboron reagents, predominantly bis(pinacolato)- and in some cases bis(catecholato)diboron [(pinB)(2) and (catB)(2), respectively]. Reductions occur upon simply mixing the amine N-oxide and the diboron reagent in a suitable solvent, at a suitable temperature. Extremely fast reductions of alkylamino- and anilino-N-oxides occur, whereas pyridyl-N-oxides undergo slower reduction. The reaction is tolerant of a variety of functionalities such as hydroxyl, thiol, and cyano groups, as well as halogens. Notably, a sensitive nucleoside N-oxide has also been reduced efficiently. The different rates with which alkylamino- and pyridyl-N-oxides are reduced has been used to perform stepwise reduction of the N,N'-dioxide of (S)-(-)-nicotine. Because it was observed that (pinB)(2) was unaffected by the water of hydration in amine oxides, the feasibility of using water as solvent was evaluated. These reactions also proceeded exceptionally well, giving high product yields. In constrast to the reactions with (pinB)(2), triethylborane reduced alkylamino-N-oxides, but pyridine N-oxide did not undergo efficient reduction even at elevated temperature. Finally, the mechanism of the reductive process by (pinB)(2) has been probed by (1)H and (11)B NMR.

  7. Hypoxia inhibits semicarbazide-sensitive amine oxidase activity in adipocytes.

    Science.gov (United States)

    Repessé, Xavier; Moldes, Marthe; Muscat, Adeline; Vatier, Camille; Chetrite, Gérard; Gille, Thomas; Planes, Carole; Filip, Anna; Mercier, Nathalie; Duranteau, Jacques; Fève, Bruno

    2015-08-15

    Semicarbazide-sensitive amine oxidase (SSAO), an enzyme highly expressed on adipocyte plasma membranes, converts primary amines into aldehydes, ammonium and hydrogen peroxide, and is likely involved in endothelial damage during the course of diabetes and obesity. We investigated whether in vitro, adipocyte SSAO was modulated under hypoxic conditions that is present in adipose tissue from obese or intensive care unit. Physical or pharmacological hypoxia decreased SSAO activity in murine adipocytes and human adipose tissue explants, while enzyme expression was preserved. This effect was time-, dose-dependent and reversible. This down-regulation was confirmed in vivo in subcutaneous adipose tissue from a rat model of hypoxia. Hypoxia-induced suppression in SSAO activity was independent of the HIF-1-α pathway or of oxidative stress, but was partially antagonized by medium acidification. Hypoxia-induced down-regulation of SSAO activity could represent an adaptive mechanism to lower toxic molecules production, and may thus protect from tissue injury during these harmful conditions. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  8. BIODEGRADATION OF AROMATIC AMINE COMPOUNDS USING MOVING BED BIOFILM REACTORS

    Directory of Open Access Journals (Sweden)

    M. Delnavaz ، B. Ayati ، H. Ganjidoust

    2008-10-01

    Full Text Available Three moving bed biofilm reactors were used to treat synthesized wastewater of aromatic amine compounds including aniline, para-diaminobenzene and para-aminophenol that are found in many industrial wastewaters. The reactors with cylindrical shape had an internal diameter and an effective depth of 10 and 60 cm, respectively. The reactors were filled with light expanded clay aggregate as carriers and operated in an aerobic batch and continuous conditions. Evaluation of the reactors' efficiency was done at different retention time of 8, 24, 48 and 72 h with an influent COD from 100 to 3500 mg/L (filling ratio of 50%. The maximum obtained removal efficiencies were 90% (influent COD=2000 mg/L, 87% (influent COD=1000 mg/L and 75% (influent COD=750 mg/L for aniline, para-diaminobenzene and para-aminophenol, respectively. In the study of decrease in filling ratio from 50 to 30 percent, 6% decrease for both para-diaminobenzene and para-aminophenol and 7% increase for aniline degradation were obtained. The removal efficiency was decreased to about 10% after 15 days of continuous loading for each of the above three substrates. In the shock loading test, initially the COD removal rate was decreased in all reactors, but after about 10 days, it has been approached to the previous values. Finally, biodegradability of aromatic amines has been proved by nuclear magnetic resonance system.

  9. Amine-oxide hybrid materials for acid gas separations

    KAUST Repository

    Bollini, Praveen

    2011-01-01

    Organic-inorganic hybrid materials based on porous silica materials functionalized with amine-containing organic species are emerging as an important class of materials for the adsorptive separation of acid gases from dilute gas streams. In particular, these materials are being extensively studied for the adsorption of CO 2 from simulated flue gas streams, with an eye towards utilizing these materials as part of a post-combustion carbon capture process at large flue gas producing installations, such as coal-fired electricity-generating power plants. In this Application Article, the utilization of amine-modified organic-inorganic hybrid materials is discussed, focusing on important attributes of the materials, such as (i) CO 2 adsorption capacities, (ii) adsorption and desorption kinetics, and (iii) material stability, that will determine if these materials may one day be useful adsorbents in practical CO 2 capture applications. Specific research needs and limitations associated with the current body of work are identified. © 2011 The Royal Society of Chemistry.

  10. Nepal : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Renforcement de la résilience des collectivités de montagne : reconstruction après le séisme à Dhungentar, au Népal ... Ce projet mettra à l'essai diverses innovations en matière d'agriculture en terrasses et offrira des stratégies aux ONG pour aider 100 000 entrepreneurs népalais en créant une nouvelle entreprise pour ...

  11. Publications | Page 54 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Nous communiquons les résultats des recherches que nous finançons et offrons du matériel de formation gratuit pour venir en aide aux chercheurs et aux institutions. ... Résultats. 531 - 540 de 2332. En Afrique, la croissance sera-t-elle synonyme d'emplois pour les jeunes ? L'Afrique est le continent du monde dont la ...

  12. Publications | Page 166 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Mainstreaming Informal and Gender in Poverty Reduction : A Handbook for Policy-makers and other Stakeholders ... En élargissant l'ensemble d'indicateurs existant pour y inclure le stress, l'anxiété et la violence reliés à l'appartenance à un sexe, ce livre présente un nouveau cadre pour la recherche sur les questions de ...

  13. Publications | Page 31 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Principes de responsabilité et de solidarité pour un accès financier équitable aux soins de santé : le cas des travailleurs de l'informel urbain du Cameroun en situation de ... D'est en ouest, les économies de l'Asie se transforment rapidement, créant des emplois pour une population croissante de jeunes travailleurs.

  14. Livres | Page 21 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Elles permettent de communiquer les résultats de nos études à d'autres chercheurs, décideurs politiques et communautés dans le monde. ... En élargissant l'ensemble d'indicateurs existant pour y inclure le stress, l'anxiété et la violence reliés à l'appartenance à un sexe, ce livre présente un nouveau cadre pour la ...

  15. Publications | Page 67 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Nous communiquons les résultats des recherches que nous finançons et offrons du matériel de formation gratuit pour venir en aide aux chercheurs et aux ... de sa capacité de générer, d'adapter et d'utiliser des connaissances scientifiques pour satisfaire aux besoins locaux en matière de santé et de développement. Or, les ...

  16. Descriptif 2006-2011 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le 28 juin 2006, le domaine de programme Innovation, politique et science (IPS) a présenté au Conseil des gouverneurs du CRDI un plan stratégique pour orienter la phase initiale (2006 2011) des recherches menées en vertu de sa toute première initiative de programme, qui a pour nom Innovation, technologie et société ...

  17. Livres | Page 34 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Auteur(s) : Stephen C. Lonergan et David B. Brooks. Maison(s) d'édition : CRDI. ISBN: Épuisé. Couverture du livre Un brevet pour la vie : La propriété intellectuelle et ses effets sur. Un brevet pour la vie : La propriété intellectuelle et ses effets sur le commerce, la biodiversité et le monde rural. L'aboutissement récent de la ...

  18. ethiopia : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le but de ce projet consiste à améliorer la compréhension des complexités du mariage d'enfants et de la parentalité pour éclairer les politiques et les programmes. Sujet: Gender. Région: Ethiopia, Peru, Zambia. Programme: Gouvernance et justice. Financement total : CA$ 1,120,200.00. Alliance statistique pour les faits ...

  19. Publications | Page 127 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le Vietnam a entrepris une ambitieuse transition d'un caractère singulier : il a tenté de transformer l'économie du pays par le biais de la libéralisation du marché, sans modifier pour autant sa structure politique centralisée. L'... Recherche pour le développement — Cambodge. Après avoir été dévasté par la guerre civile et ...

  20. Nouveaux centres de cyberpolitique pour les pays du Sud | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    13 avr. 2018 ... L'appel ouvert avait pour but de cibler les organismes indépendants voués à la recherche sur les politiques qui s'appuient sur la recherche pour éclairer et influencer les politiques nationales dans les domaines des droits numériques, de la cybersécurité et des politiques d'innovation. Parmi les 59 ...

  1. Sheikh al-Amin Mazrui (1891-1947) and the Dilemma of Islamic Law ...

    African Journals Online (AJOL)

    Sheikh al-Amin Mazrui (1891-1947) and the Dilemma of Islamic Law in the Kenyan Legal System in the 21st Century ... While Sheikh al-Amin was radical in initiating educational and social transformation of the Muslim community in East Africa, his reform schemata in the realm of Islamic law was generally less impressive, ...

  2. Elaboration and characterisation of acids catalyst for the obtention of amines

    International Nuclear Information System (INIS)

    Khemaissia, S.; Zaoui, B.; Nibou, D.

    1997-04-01

    The nuclear energy has shown the interest of aminated substances as solvents for removal and purification. These extractants are generally used in uranium ores treatment processes and several technology fields, specially, in organic and pharmaceutical industries. The present work deals with elaboration and characterization of acidic solid catalyst used in aminated extractants obtaining

  3. Amination of Aryl Halides and Esters Using Intensified Continuous Flow Processing.

    Science.gov (United States)

    Kohl, Thomas M; Hornung, Christian H; Tsanaktsidis, John

    2015-09-25

    Significant process intensification of the amination reactions of aryl halides and esters has been demonstrated using continuous flow processing. Using this technology traditionally difficult amination reactions have been performed safely at elevated temperatures. These reactions were successfully conducted on laboratory scale coil reactor modules with 1 mm internal diameter (ID) and on a preparatory scale tubular reactor with 6 mm ID containing static mixers.

  4. Extension of the cubic-plus-association (CPA) equation of state to amines

    DEFF Research Database (Denmark)

    Kaarsholm, Mads Kristian; Derawi, Samer; Michelsen, Michael Locht

    2005-01-01

    The cubic-plus-association (CPA) equation of state has been extended to modeling mixtures containing amines. Special focus was given to primary and secondary amines, which are known to self-associate, thus forming hydrogen bonds in mixtures with alkanes. Pure-compound parameters have been...

  5. Tris{4-[(1,3-diphenyl-1H-pyrazol-4-ylmethylene]-41-aminobiphenyl}amine

    Directory of Open Access Journals (Sweden)

    Sandhya P. Veettil

    2010-04-01

    Full Text Available Tris{4-[(1,3-diphenyl-1H-pyrazol-4-ylmethylene]-41-aminobiphenyl}amine was synthesized from N-(4-bromophenyl-N-[(1,3-diphenyl-1H-pyrazol-4-ylmethylene]amine and tris(4-bromophenylamine based on Ullmann coupling reaction. The synthesized compound was characterized by NMR, IR, MS and elemental analysis.

  6. Activity and selectivity control in reductive amination of butyraldehyde over noble metal catalysts.

    NARCIS (Netherlands)

    Bodis, E.; Lefferts, Leonardus; Muller, T.E.; Pestman, R.; Lercher, J.A.

    2005-01-01

    Approaches to control selectivity and activity in the catalytic reductive amination of butyraldehyde with ammonia over carbon supported noble metal catalysts (Ru, Rh, Pd, and Pt) were explored. Detailed analysis of the reaction network shows that the Schiff base N-[butylidene]butan-1-amine is the

  7. Nickel-Catalyzed Synthesis of Primary Aryl and Heteroaryl Amines via C–O Bond Cleavage

    KAUST Repository

    Yue, Huifeng

    2017-03-13

    A nickel-catalyzed protocol for the conversion of aryl and heteroaryl alcohol derivatives to primary and secondary aromatic amines via C(sp2)-O bond cleavage is described. The new amination protocol can be applied to a range of substrates bearing diverse functional groups and uses readily available benzophenone imines as an effective nitrogen source.

  8. Asymmetric Biocatalytic Amination of Ketones at the Expense of NH3 and Molecular Hydrogen.

    Science.gov (United States)

    Holzer, Anja K; Hiebler, Katharina; Mutti, Francesco G; Simon, Robert C; Lauterbach, Lars; Lenz, Oliver; Kroutil, Wolfgang

    2015-05-15

    A biocatalytic system is presented for the stereoselective amination of ketones at the expense of NH3 and molecular hydrogen. By using a NAD(+)-reducing hydrogenase, an alanine dehydrogenase, and a suitable ω-transaminase, the R- as well as the S-enantiomer of various amines could be prepared with up to >99% ee and 98% conversion.

  9. One-pot Reductive Amination of Carbonyl Compounds with NaBH4 ...

    Indian Academy of Sciences (India)

    product. Another problem during reductive amination of carbonyl compounds with primary amines is over- alkylation and direct reduction of carbonyl compound to the corresponding alcohol. In these cases, formation and isolation of the imines which followed by reduction can avoid the problem, but the need to isolate imines.

  10. NOx reduction using amine reclaimer wastes (ARW) generated in post combustion CO2 capture

    DEFF Research Database (Denmark)

    Botheju, Deshai; Glarborg, Peter; Tokheim, Lars-Andre

    2012-01-01

    Amine reclaimer wastes (ARW) generated in CO2 capture processes demand suitable disposal means. Such wastes contain remaining amine, NH3 and other degradation compounds. This study investigated the potential of using ARW as a NOx reducing agent, under laboratory conditions in a flow reactor. A si...... to combustion processes, including cement industry kilns....

  11. Amine metabolism in the human brain : evaluation of the probenecid test

    NARCIS (Netherlands)

    Korf, Jacob

    1971-01-01

    There are indirect indications, that biogenic amines in the brain are concerned with pathological states such as depression (serotonin, 5HT and noradrenaline, NA) and Parkonsonism (dopamine, DA). These indications were obtained from measurements of amines and their metabolites in pe - ripheral

  12. Novel in vivo active anti-malarials based on a hydroxy-ethyl-amine scaffold.

    Science.gov (United States)

    Ciana, Claire-Lise; Siegrist, Romain; Aissaoui, Hamed; Marx, Léo; Racine, Sophie; Meyer, Solange; Binkert, Christoph; de Kanter, Ruben; Fischli, Christoph; Wittlin, Sergio; Boss, Christoph

    2013-02-01

    A novel series of anti-malarials, based on a hydroxy-ethyl-amine scaffold, initially identified as peptidomimetic protease inhibitors is described. Combination of the hydroxy-ethyl-amine anti-malarial phramacophore with the known Mannich base pharmacophore of amodiaquine (57) resulted in promising in vivo active novel derivatives. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Industrial Process Design for the Production of Aniline by Direct Amination

    NARCIS (Netherlands)

    Driessen, Rick T.; Kamphuis, Peter; Mathijssen, Lydwien; Zhang, Ruo; van der Ham, Louis G.J.; van den Berg, Henk; Zeeuw, Arend Jan

    2017-01-01

    The objective is to design a plant from raw material to product for the production of aniline by direct amination of benzene. The process design is started on a conceptual level and ended on a basic engineering level as well as a techno-economical evaluation. The amination of benzene by

  14. An Alumino-Mannich Reaction of Organoaluminum Reagents, Silylated Amines, and Aldehydes.

    Science.gov (United States)

    Tarasewicz, Anika; Ensan, Deeba; Batey, Robert A

    2018-03-08

    A multi-component coupling using organoaluminum reagents, silylated amines, and aldehydes results in the formation of tertiary amines. Both alkenyl- and alkylaluminum reagents undergo reaction with iminium ion substrates for which the corresponding Petasis borono-Mannich reactions are unsuccessful. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Inhibition of Microbial Growth by Fatty Amine Catalysts from Polyurethane Foam Test Tube Plugs

    Science.gov (United States)

    Bach, John A.; Wnuk, Richard J.; Martin, Delano G.

    1975-01-01

    When polyurethane foam test tube plugs are autoclaved, they release volatile fatty amines that inhibit the growth of some microorganisms. The chemical structures of these amines were determined by the use of a gas chromatographmass spectrometer. They are catalysts used to produce the foam. The problem of contaminating growth media with toxic substances released from polymeric materials is discussed. PMID:1096816

  16. N-heterocyclic carbene copper(I) catalysed N-methylation of amines using CO2

    KAUST Repository

    Santoro, Orlando

    2015-09-30

    The N-methylation of amines using CO2 and PhSiH3 as source of CH3 was efficiently performed using a N-heterocyclic carbene copper(I) complex. The methodology was found compatible with aromatic and aliphatic primary and secondary amines. Synthetic and computational studies have been carried out to support the proposed reaction mechanism for this transformation.

  17. Regioselective iodination of aryl amines using 1,4-dibenzyl-1,4 ...

    African Journals Online (AJOL)

    1,4-Dibenzyl-1,4-diazoniabicyclo[2.2.2]octane dichloroiodate is an efficient and regioselective reagent for iodination of aryl amines. A wide variety of aryl amines in reaction with this reagent afforded regioselectively iodinated products. The iodination reaction can be carried out in solution or under solvent-free condition at ...

  18. Mechanistic investigation of the iridium-catalysed alkylation of amines with alcohols

    DEFF Research Database (Denmark)

    Fristrup, Peter; Tursky, Matyas; Madsen, Robert

    2012-01-01

    where the intermediate aldehyde stays coordinated to the iridium catalyst and reacts with the amine to give a hemiaminal which is also bound to the catalyst. Dehydration to the imine and reduction to the product amine also takes place without breaking the coordination to the catalyst. The fact...

  19. Radiation-chemical synthesis of amine-type adsorbent on the base of nonwoven polypropylene fibers

    International Nuclear Information System (INIS)

    Bondar', Yu.V.; Plyushchaj, I.V.; Bondar', Yu.V.; Plyushchaj, I.V.

    2011-01-01

    A sorption-active material based on polypropylene nonwoven fibers carrying amine-type functional groups is synthesized by reacting epoxy groups of the poly-GMA graft chains with diethylenetriamine. Some peculiarities of the amination process are investigated, and the adsorption parameters of a synthesized sample are determined.

  20. Enhanced reactivities toward amines by introducing an imine arm to the pincer ligand: Direct coupling of two amines to form an imine without oxidant

    KAUST Repository

    He, Lipeng

    2012-07-23

    Dehydrogenative homocoupling of primary alcohols to form esters and coupling of amines to form imines was accomplished using a class of novel pincer ruthenium complexes. The reactivities of the ruthenium pincer complexes for the direct coupling of amines to form imines were enhanced by introducing an imine arm to the pincer ligand. Selective oxidation of benzylamines to imines was achieved using aniline derivatives as the substrate and solvent. © 2012 American Chemical Society.

  1. A practical and catalyst-free trifluoroethylation reaction of amines using trifluoroacetic acid

    Science.gov (United States)

    Andrews, Keith G.; Faizova, Radmila; Denton, Ross M.

    2017-06-01

    Amines are a fundamentally important class of biologically active compounds and the ability to manipulate their physicochemical properties through the introduction of fluorine is of paramount importance in medicinal chemistry. Current synthesis methods for the construction of fluorinated amines rely on air and moisture sensitive reagents that require special handling or harsh reductants that limit functionality. Here we report practical, catalyst-free, reductive trifluoroethylation reactions of free amines exhibiting remarkable functional group tolerance. The reactions proceed in conventional glassware without rigorous exclusion of either moisture or oxygen, and use trifluoroacetic acid as a stable and inexpensive fluorine source. The new methods provide access to a wide range of medicinally relevant functionalized tertiary β-fluoroalkylamine cores, either through direct trifluoroethylation of secondary amines or via a three-component coupling of primary amines, aldehydes and trifluoroacetic acid. A reduction of in situ-generated silyl ester species is proposed to account for the reductive selectivity observed.

  2. Enzymatic treatment of sulfonated aromatic amines generated from reductive degradation of reactive azo dyes.

    Science.gov (United States)

    Biswas, Mousumi Mani; Taylor, Keith E; Bewtra, Jatinder K; Biswas, Nihar

    2007-04-01

    Anaerobic degradation, an effective treatment process of textile industry effluent, generates sulfonated aromatic amines, which are carcinogenic, mutagenic, and resistant to microbial degradation. These aromatic amines can be effectively removed by oxidative polymerization catalyzed by peroxidase enzyme. The amines, generated in this study from the anaerobic reduction by zero-valent iron of two reactive azo dyes (Reactive Red 2 [RR2] and Reactive Black 5 [RB5]), were successfully removed (90%) by Arthromyces ramosus peroxidase (ARP). For better understanding of the process, enzymatic treatment of two model compounds, diphenylamine (DPA) and 2-amino-8-naphthol-3,6-disulfonic acid (ANDSA), were also studied. Diphenylamine has a similar diarylamine bond as RR2. The ANDSA has a similar structure as the dye reduction products. The secondary amine bond in DPA and RR2 were oxidized by ARP. Enzymatic reaction of sulfonated aromatic amines generated soluble colored compounds, which were removed by coagulant. Optimum reaction parameters were also determined.

  3. In Situ Preparation of Polyether Amine Functionalized MWCNT Nanofiller as Reinforcing Agents

    Directory of Open Access Journals (Sweden)

    Ayber Yıldrım

    2014-01-01

    Full Text Available In situ preparation of polyether amine functionalized cross-linked multiwalled carbon nanotube (MWCNT nanofillers may improve the thermal and mechanical properties of the composites in which they are used as reinforcing agents. The reduction and functionalization of MWCNT using ethylenediamine in the presence of polyether amine produced stitched MWCNT's due to the presence of two amine (–NH2 functionalities on both sides of the polymer. Polyether amine was chosen to polymerize the carboxylated MWCNT due to its potential to form bonds with the amino groups and carboxyl groups of MWCNT which produces a resin used as polymeric matrix for nanocomposite materials. The attachment of the polyether amine (Jeffamine groups was verified by TGA, FT-IR, XRD, SEM, and Raman spectroscopy. The temperature at which the curing enthalpy is maximum, observed by DSC, was shifted to higher values by adding functionalized MWCNT. SEM images show the polymer formation between MWCNT sheets.

  4. Determination of oxyfluorfen herbicide and oxyfluorfen amine residues in garbanzo beans by liquid chromatography.

    Science.gov (United States)

    Zhou, M; Miles, C J

    1991-01-01

    Oxyfluorfen and oxyfluorfen amine were determined by liquid chromatography (LC) with ultraviolet (UV) and photoconductivity detection (PCD). A simple extraction procedure acceptably recovered both analytes from garbanzo beans over a wide range of fortifications (0.05 to 20 ppm) (83 +/- 4 for oxyfluorfen; 85 +/- 4 for oxyfluorfen amine). Percent recoveries decreased slightly as the fortification level decreased. Both analytes could be determined simultaneously at a concentration greater than 0.2 ppm in garbanzo beans. Detection limits were 3 ng for oxyfluorfen and 100 ng for oxyfluorfen amine using LC/UV, and 12 ng for both oxyfluorfen and oxyfluorfen amine with LC/PCD. Different knitted reaction coils and photoreactors were evaluated. Photoproduct yields and identification were determined by ion chromatography. The LC/PCD method measures oxyfluorfen and oxyfluorfen amine separately and has a shorter analysis time, while the standard method using gas chromatography measures total residues and is more sensitive.

  5. AMMO-Prot: amine system project 3D-model finder.

    Science.gov (United States)

    Navas-Delgado, Ismael; Montañez, Raúl; Pino-Angeles, Almudena; Moya-García, Aurelio A; Urdiales, José Luis; Sánchez-Jiménez, Francisca; Aldana-Montes, José F

    2008-04-25

    Amines are biogenic amino acid derivatives, which play pleiotropic and very important yet complex roles in animal physiology. For many other relevant biomolecules, biochemical and molecular data are being accumulated, which need to be integrated in order to be effective in the advance of biological knowledge in the field. For this purpose, a multidisciplinary group has started an ontology-based system named the Amine System Project (ASP) for which amine-related information is the validation bench. In this paper, we describe the Ontology-Based Mediator developed in the Amine System Project (http://asp.uma.es) using the infrastructure of Semantic Directories, and how this system has been used to solve a case related to amine metabolism-related protein structures. This infrastructure is used to publish and manage not only ontologies and their relationships, but also metadata relating to the resources committed with the ontologies. The system developed is available at http://asp.uma.es/WebMediator.

  6. Factors influencing phase-disengagement rates in solvent-extraction systems employing tertiary amine extractants

    International Nuclear Information System (INIS)

    Moyer, B.A.; McDowell, W.J.

    1981-01-01

    The primary purpose of the present investigation was to examine the effects of amine size and structure on phase disengagement. Nine commercial tertiary amines were tested together with four laboratory-quality amines for uranium extraction and both organic-continuous (OC) and aqueous-continuous (AC) phase disengagement under Amex-type conditions. Synthetic acid sulfate solutions with and without added colloidal silica and actual ore leach solutions were used as the aqueous phases. Phase disengagement results were correlated with amine size and branching and solution wetting behavior on a silicate (glass) surface. The results suggest that the performance of some Amex systems may be improved by using branched chain tertiary amine extractants of higher molecular weight than are now normally used

  7. Effect of foamability index of short chain alkyl amines on flotation of quartz

    Directory of Open Access Journals (Sweden)

    Szczerkowska Sabina

    2016-01-01

    Full Text Available Amines can be used for flotation of various minerals, especially quartz. The flotation efficiency of quartz depends on the amine type and dose. It was proved that the shorter alkyl amine, higher amine concentration has to be used to recover quartz at the same level. In flotation amines play a role of both collectors and frothers. The ability of a amine to collect particles can be expressed in the form of contact angle, while the foaming properties by different parameters including dynamic foamability index (DFI and critical coalescence concentration (CCC. Determination of DFI and CCC requires advanced techniques and methods. Therefore, in this paper a rapid and facile method for determination of foaming properties of amines and also other surfactants was used. It was based on measuring the initial foam and froth heights in a conventional flotation machine at different concentrations of surfactants. The foam height-concentration curve was described by utilizing an empirical equation which was based on one-adjustable parameter called the foamability index (FI. In this work the foamability index was determined for butylamine (ButNH2, hexylamine (HexNH2 and octylamine (OctNH2 as examples of short chain alkyl amines. The determined foamability indices were 92, 12 and 4 mg/dm3 for ButNH2, HexNH2 and OctNH2, respectively. It was shown that when the flotation results of quartz were presented in the form of recovery versus normalized amine concentration in relation to the foamability index (c/FI, all the experimental data points converged to one curve. It indicates that amines act similarly but at different concentrations expressed as FI. The foamability index seems to be a useful parameter for characterizing any flotation frother.

  8. Multi-Objective Optimization for Solid Amine CO2 Removal Assembly in Manned Spacecraft

    Directory of Open Access Journals (Sweden)

    Rong A

    2017-07-01

    Full Text Available Carbon Dioxide Removal Assembly (CDRA is one of the most important systems in the Environmental Control and Life Support System (ECLSS for a manned spacecraft. With the development of adsorbent and CDRA technology, solid amine is increasingly paid attention due to its obvious advantages. However, a manned spacecraft is launched far from the Earth, and its resources and energy are restricted seriously. These limitations increase the design difficulty of solid amine CDRA. The purpose of this paper is to seek optimal design parameters for the solid amine CDRA. Based on a preliminary structure of solid amine CDRA, its heat and mass transfer models are built to reflect some features of the special solid amine adsorbent, Polyethylenepolyamine adsorbent. A multi-objective optimization for the design of solid amine CDRA is discussed further in this paper. In this study, the cabin CO2 concentration, system power consumption and entropy production are chosen as the optimization objectives. The optimization variables consist of adsorption cycle time, solid amine loading mass, adsorption bed length, power consumption and system entropy production. The Improved Non-dominated Sorting Genetic Algorithm (NSGA-II is used to solve this multi-objective optimization and to obtain optimal solution set. A design example of solid amine CDRA in a manned space station is used to show the optimal procedure. The optimal combinations of design parameters can be located on the Pareto Optimal Front (POF. Finally, Design 971 is selected as the best combination of design parameters. The optimal results indicate that the multi-objective optimization plays a significant role in the design of solid amine CDRA. The final optimal design parameters for the solid amine CDRA can guarantee the cabin CO2 concentration within the specified range, and also satisfy the requirements of lightweight and minimum energy consumption.

  9. Characterization of molybdenum interfacial crud in a uranium mill that employs tertiary-amine solvent extraction

    International Nuclear Information System (INIS)

    Moyer, B.; McDowell, W.J.

    1983-01-01

    In the present work, samples of a molybdenum-caused green gummy interfacial crud from an operating western US uranium mill have been physically and chemically examined. Formaton of cruds of this description has been a long-standing problem in the use of tertiary amine solvent extraction for the recovery of uranium from low-grade ores (Amex Process). The crud is essentially an organic-continuous dispersion containing about 10 wt % aqueous droplets and about 37 wt % greenish-yellow crystalline solids suspended in kerosene-amine process solvent. The greenish-yellow crystals were found to be a previously unknown double salt of tertiary amine molybdophosphate with three tertiary amine chlorides having the empirical formula (R 3 NH) 3 [PMo 12 O 40 ].3(R 3 NH)Cl. To confirm the identification of the compound, a pure trioctylamine (TOA) analog was synthesized. In laboratory extraction experiments, it was demonstrated that organic-soluble amine molydophosphate forms slowly upon contact of TOA solvent with dilute sulfuric acid solutions containing low concentrations of molybdate and phosphate. If the organic solutions of amine molybdophosphate were then contacted with aqueous NaCl solutions, a greenish-yellow precipitate of (TOAH) 3 [PMo 12 O 40 ].3(TOAH)Cl formed at the interface. The proposed mechanism for the formation of the crud under process conditions involves build up of molybdenum in the solvent, followed by reaction with extracted phosphate to give dissolved amine molybdophosphate. The amine molybdophosphate then co-crystallizes with amine chloride, formed during the stripping cycle, to give the insoluble double salt, which precipitates as a layer of small particles at the interface. The proposed solution to the problem is the use of branched-chain, instead of straight-chain, tertiary amine extractants under the expectation that branching would increase the solubility of the double salt. 2 figures, 5 tables

  10. Binding Constant of Amines to Water/AOT/n-Hexene Reverse Micelles. Influence of the Chemical Structure

    Directory of Open Access Journals (Sweden)

    J. J. Silber

    2000-03-01

    Full Text Available The distribution of different amines between n-hexane bulk and the micellar pseudophase of AOT reverse micelles were measured by a fluorometric method. An independent method was used to corroborate the incorporation of the amines to the interface. The effect of the amine structure on the binding constant was analysed.

  11. Palladium-Catalyzed Enantioselective C-H Activation of Aliphatic Amines Using Chiral Anionic BINOL-Phosphoric Acid Ligands.

    Science.gov (United States)

    Smalley, Adam P; Cuthbertson, James D; Gaunt, Matthew J

    2017-02-01

    The design of an enantioselective Pd(II)-catalyzed C-H amination reaction is described. The use of a chiral BINOL phosphoric acid ligand enables the conversion of readily available amines into synthetically valuable aziridines in high enantiomeric ratios. The aziridines can be derivatized to afford a range of chiral amine building blocks incorporating motifs readily encountered in pharmaceutically relevant molecules.

  12. Investigations of stabilizing additives—III. Antagonistic effect of thioester on hindered amine antioxidants for radiation stability

    Science.gov (United States)

    Williams, J. L.; Williams, E. E.; Dunn, T. S.

    The use of hindered amines as primary antioxidants has been investigated both in a model antioxidant activity system and polypropylene. Also, the effectiveness of hindered amines in the presence of thioester has been evaluated. The antagonistic aspects of thioester on the ability of hindered amine to prevent polymer oxidation is discussed.

  13. Decodeurs rapides pour codes topologiques quantiques

    Science.gov (United States)

    Duclos-Cianci, Guillaume

    L'encodage topologique de l'information quantique a attire beaucoup d'attention, car c'est un modele qui semble propice a resister aux erreurs locales. Tout d'abord, le modele du calcul topologique est base sur la statistique anyonique non-Abelienne universelle et sur son controle. Des anyons indesirables peuvent apparaitre soudainement, en raison de fluctuations thermiques ou de processus virtuels. La presence de ces anyons peut corrompre l'information encodee, il est necessaire de les eliminer: la correction consiste a fusionner les defauts tout en preservant la topologie du systeme. Ensuite, dans le cas des codes topologiques, on doit aussi proteger l'information encodee dans la topologie. En effet, dans ces systemes, on n'a acces qu'a une fraction de l'information decrivant l'erreur. Elle est recueillie par des mesures et peut etre interpretee en termes de particules. Ces defauts peuplent le code et doivent etre annihiles adequatement dans le but de preserver l'information encodee. Dans ce memoire, nous proposons un algorithme efficace, appele decodeur, pouvant etre utilise dans les deux contextes decrits ci-haut. Pour y parvenir, cet algorithme s'inspire de methodes de renormalisation et de propagation de croyance. Il est exponentiellement plus rapide que les methodes deja existantes, etant de complexite O (ℓ2 log ℓ) en serie et, si on parallelise, O (log ℓ) en temps, contre O (ℓ6) pour les autres decodeurs. Le temps etant le facteur limitant dans le probleme du decodage, cette caracteristique est primordiale. De plus, il tolere une plus grande amplitude de bruit que les methodes existantes; il possede un seuil de ˜ 16.5% sur le canal depolarisant surpassant le seuil deja etabli de ˜ 15.5%. Finalement, il est plus versatile. En effet, en etant limite au code de Kitaev, on ne savait pas decoder les codes topologiques de maniere generale (e.g. codes de couleur). Or, le decodeur propose dans ce memoire peut traiter la grande classe des codes

  14. Images du Mage, images pour le Mage

    Directory of Open Access Journals (Sweden)

    Daniel GREGORIO

    2007-01-01

    Full Text Available Les œuvres d’Alphonse X proposent diverses représentations du mage, qui en font, tour à tour, l’ennemi ou l’allié de la religion chrétienne. Il est vrai que parfois, comme le montre l’histoire de Simon le magicien, la pratique de la magie implique un commerce direct et néfaste avec les forces infernales. Néanmoins, les personnages de Merlin et des Rois Mages, tels qu’ils sont présentés par Alphonse X, démontrent que magie et religion peuvent cohabiter, à condition toutefois que le mage croit en la virginité de Marie et en l’Incarnation et que sa pratique magique soit bénéfique pour la communauté. Ce bénéfice requiert parfois la reconstruction de l’univers quotidien ; pour ce faire, le magicien doit savoir quand et comment utiliser des objets et des pentacles, qui lui permettront de soumettre les forces surnaturelles. Il doit donc posséder une connaissance approfondie du monde naturel et des esprits qui, conjuguée à sa foi religieuse, l’empêchera de tomber dans la démonolâtrie.Las obras alfonsíes proponen diversas aproximaciones al personaje del mago, generalmente considerado como un ser antagónico del hombre religioso. Es cierto que en algunas ocasiones, como ocurre con Simón el mago, la práctica de las artes mágicas significa un trato directo y nefasto con las fuerzas infernales. Sin embargo, personajes como Merlín o los Reyes Magos, tal y como los describe Alfonso X, subrayan una posible cohabitación entre magia y religión sin que la práctica de la una signifique la exclusión de la otra. Sólo hay que cumplir con dos condiciones : creer en la virginidad de María y que Dios se hizo hombre, y proporcionar a la comunidad un beneficio claro. Este beneficio requiere en ocasiones remodelar lo cotidiano, utilizando objetos y pentáculos, en circunstancias extremadamente determinadas, lo que implica un conocimiento exhaustivo tanto del mundo natural como del simbólico y de los espíritus. Es este

  15. Pour une ingénierie des Environnements Informatiques pour l'Apprentissage Humain

    OpenAIRE

    Tchounikine , Pierre

    2002-01-01

    Nous proposons dans cet article une réflexion sur la notion d'ingénierie des EIAH (Environnements Informatiques pour l'Apprentissage Humain). Nous posons tout d'abord une définition de l'ingénierie des EIAH : travaux visant à définir des éléments de méthodes et de techniques reproductibles et/ou réutilisables facilitant la mise en place (conception – réalisation – expérimentation – évaluation - diffusion) d'environnements de formation ou d'apprentissage (dans leur articulation avec les dispos...

  16. Comment agir pour raviver l'espoir ? Pour un traitement efficace du ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    28 févr. 2011 ... Dix pour cent de la population mondiale vit dans cette région qui affiche près de 70 % des cas d'infection par le VIH dans le monde et 90 % des décès causés par le sida. En 2005, on y a relevé environ 2,7 millions de nouveaux cas, ce qui porterait à 24,5 millions le nombre de personnes vivant avec le ...

  17. Enthalpy of cooperative hydrogen bonding in complexes of tertiary amines with aliphatic alcohols: Calorimetric study

    International Nuclear Information System (INIS)

    Zaitseva, Ksenia V.; Varfolomeev, Mikhail A.; Novikov, Vladimir B.; Solomonov, Boris N.

    2011-01-01

    Research highlights: → Solution enthalpies of aliphatic alcohols in tertiary amines and vice versa were measured. → The enthalpies of specific interaction of amines in aliphatic alcohols are lower than the enthalpies of hydrogen bonding in 1:1 complexes amine-alcohol determined in base media. → Hydrogen bond cooperativity factors in multi-particle complexes of alcohols with aromatic amines are approximately equal for all alcohols. → Hydrogen bond cooperativity factors in multi-particle complexes of alcohols with trialkylamines decrease with increasing of alkyl radical length in alcohol and amine molecules. - Abstract: The work is devoted to the investigation of thermodynamics of specific interaction of the tertiary aliphatic and aromatic amines with associated solvents as which aliphatic alcohols were taken. Solution enthalpies of aliphatic alcohols in amines (tri-n-propylamine, 2-methylpyridine, 3-methylpyridine, N-methylimidazole) as well as amines in alcohols were measured at infinite dilution. The enthalpies of specific interaction (H-bonding) in systems studied were determined based on experimental data. The enthalpies of specific interaction of amines in aliphatic alcohols significantly lower than the enthalpies of hydrogen bonding in complexes amine-alcohol of 1:1 composition determined in base media due to the reorganization of aliphatic alcohols as solvents. The determination of solvent reorganization contribution makes possible to define the hydrogen bonding enthalpies of amines with clusters of alcohols. Obtained enthalpies of hydrogen bonding in multi-particle complexes are sensitive to the influence of cooperative effect. It was shown, that hydrogen bond cooperativity factors in multi-particle complexes of alcohols with amines are approximately equal for all alcohols when pyridines and N-methylimidazole as solutes are used. At the same time, H-bonding cooperativity factors in complexes of trialkylamines with associative species of alcohols

  18. New insights into controlling tube-bundle fouling using alternative amines

    International Nuclear Information System (INIS)

    Turner, C.W.; Klimas, S.J.; Guzonas, D.A.; Frattini, P.L.; Fruzzetti, K.

    2002-01-01

    A volatile amine is added to the secondary heat-transport system of a nuclear power plant to reduce the rate of corrosion and corrosion product transport in the feedwater and to protect steam generator (SG) crevices and materials exposed to steam condensate. Volatility and base strength of the amine at the SG operating temperature are two important considerations when choosing the optimum amine (or mixture of amines) for corrosion control in the steam cycle. Atomic Energy of Canada Limited (AECL) and Electric Power Research Institute (EPRI) have been collaborating in an extensive investigation of the effectiveness of amines at controlling the rate of tube-bundle fouling under SG operating conditions. Tests have been performed using a radiotracing technique in a high-temperature fouling loop facility at Chalk River Laboratories operated by AECL. This investigation has provided new insights into the role played by the amine in determining the rate of tube-bundle fouling in the SG. These insights are being used by AECL and EPRI to develop criteria for the selection of an amine that has optimum properties for both corrosion control and deposit control in the secondary heat transport system. The investigation has found that the rate of tube-bundle fouling is strongly dependent upon the surface chemistry of the corrosion products. For example, the fouling rates of fully oxidized iron oxides, such as hematite and lepidocrocite, are at least an order of magnitude greater than the fouling rate of magnetite under identical operating conditions. The difference is related to the sign of the surface charge on the corrosion products at temperature. The choice of amine for pH-control also influences the fouling rate. This was originally thought to be a surface-charge effect as well, but recent tests have suggested that it is related to the role that the amine plays in governing the rate of deposit consolidation on the heat-transfer surface. Amines that promote a high rate of

  19. Michael Addition Polymerization of Trifunctional Amine and Acrylic Monomer: A Versatile Platform for Development of Biomaterials.

    Science.gov (United States)

    Cheng, Weiren; Wu, Decheng; Liu, Ye

    2016-10-10

    Michael addition polymerizations of amines and acrylic monomers are versatile approaches to biomaterials for various applications. A combinatorial library of poly(β-amino ester)s and diverse poly(amido amine)s from diamines and diacrylates or bis(acrylamide)s have been reported, respectively. Furthermore, novel linear and hyperbranched polymers from Michael addition polymerizations of trifunctional amines and acrylic monomers significantly enrich this category of biomaterials. In this Review, we focus on the biomaterials from Michael addition polymerizations of trifunctional amines and acrylic monomers. First we discuss how the polymerization mechanisms, which are determined by the reactivity sequence of the three types of amines of trifunctional amines, i.e., secondary (2°) amines (original), primary (1°) amines, and 2° amines (formed), are affected by the chemistry of monomers, reaction temperature, and solvent. Then we update how to design and synthesize linear and hyperbranched polymers based on the understanding of polymerization mechanisms. Linear polymers containing 2° amines in the backbones can be obtained from polymerizations of diacrylates or bis(acrylamide)s with equimolar trifunctional amine, and several approaches, e.g., 2A 2 +BB'B″, A 3 +2BB'B', A 2 +BB'B″, to hyperbranched polymers are developed. Further through molecular design of monomers, conjugation of functional species to 2° amines in the backbones of linear polymers and the abundant terminal groups of hyperbranched polymers, the amphiphilicity of polymers can be adjusted, and additional stimuli, e.g., thermal, redox, reactive oxidation species (ROS), and light, responses can be integrated with the intrinsic pH response. Finally we discuss the applications of the polymers for gene/drug delivery and bioimaging through exploring their self-assemblies in various motifs, e.g., micelles, polyplexes particles/nanorings and hydrogels. Redox-responsive hyperbranched polymers can display 300

  20. Highly Aminated Mesoporous Silica Nanoparticles with Cubic Pore Structure

    KAUST Repository

    Suteewong, Teeraporn

    2011-01-19

    Mesoporous silica with cubic symmetry has attracted interest from researchers for some time. Here, we present the room temperature synthesis of mesoporous silica nanoparticles possessing cubic Pm3n symmetry with very high molar ratios (>50%) of 3-aminopropyl triethoxysilane. The synthesis is robust allowing, for example, co-condensation of organic dyes without loss of structure. By means of pore expander molecules, the pore size can be enlarged from 2.7 to 5 nm, while particle size decreases. Adding pore expander and co-condensing fluorescent dyes in the same synthesis reduces average particle size further down to 100 nm. After PEGylation, such fluorescent aminated mesoporous silica nanoparticles are spontaneously taken up by cells as demonstrated by fluorescence microscopy.

  1. Purification and characterization of amine oxidase from soybean seedlings.

    Science.gov (United States)

    Vianello, F; Di Paolo, M L; Stevanato, R; Gasparini, R; Rigo, A

    1993-11-15

    A simple and rapid procedure for purification of soybean seedling amine oxidase is reported. The crude enzyme, obtained by ammonium sulfate fractionation was purified by ion-exchange chromatography on a cellulose phosphate column and batch affinity chromatography on 6-aminohexyl-Sepharose. Cyclohexylamine, a competitive inhibitor, was utilized to elute the enzyme. A homogeneous enzyme was obtained with a yield higher than 25%, the content of minor components being lauryl sulfate-polyacrylamide gel electrophoresis. The enzyme is a dimer and contains two Cu2+ ion per molecule. Its EPR spectrum is typical of Cu2+ in a tetragonal symmetry. The enzyme oxidizes cadaverine at high rate, the specific activity being 4.3 mukat/mg. Molecular, spectroscopic, and kinetic properties of this enzyme are reported.

  2. Polycondensation Resins by Flavonoid Tannins Reaction with Amines

    Directory of Open Access Journals (Sweden)

    Francisco-Jose Santiago-Medina

    2017-01-01

    Full Text Available Reaction of a condensed flavonoid tannin, namely mimosa tannin extract with a hexamethylene diamine, has been investigated. For that purpose, catechin was also used as a flavonoid model compound and treated in similar conditions. Solid-state cross-polarisation/magic-angle spinning (CP-MAS carbon 13 nuclear magnetic resonance (13C NMR and matrix assisted laser desorption ionisation time of flight (MALDI-ToF mass spectroscopy studies revealed that polycondensation compounds leading to resins were obtained by the reaction of the amines with the phenolic hydroxy groups of the tannin. Simultaneously, a second reaction leading to the formation of ionic bonds between the two groups occurred. These new reactions have been shown to clearly lead to the reaction of several phenolic hydroxyl groups, and flavonoid unit oligomerisation, to form hardened resins.

  3. Structural Influence on Excited State Dynamics in Simple Amines

    DEFF Research Database (Denmark)

    Klein, Liv Bærenholdt

    experiments with calculations, provides new insight into the nature of the internal conversion processes that mediate the dynamical evolution between Rydberg states, and how structural variations in simple amine system have a large impact on the non-adiabatic processes. The experimental method of choice...... is femtosecond time-resolved photoelectron velocity map imaging (VMI), which is a newtechnique in the Copenhagen lab. The design, building and implementation of the VMI spectrometer has been a very substantial part of the thesis work. This techniques oers enhanced information content in the form of ecient...... investigated organic species containing N-H bonds, where the ultrafast evolution of the 3s state into valence character iswell-established. Even though the temporal evolution is too fast to be resolved by the experiment, the angle-resolved information still allows for the observation of this process...

  4. Thermodynamics of organic mixtures containing amines. VIII. Systems with quinoline

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Juan Antonio [G.E.T.E.F., Grupo Especializado en Termodinamica de Equilibrio entre Fases, Departamento de Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, E-47071 Valladolid (Spain)], E-mail: jagl@termo.uva.es; Domanska, Urszula; Zawadzki, Maciej [Physical Chemistry Division, Faculty of Chemistry, Warsaw University of Technology, 00-664 Warsaw (Poland)

    2008-08-15

    (Solid + liquid) equilibrium temperatures for mixtures containing quinoline and 1-dodecanol, 1-hexadecanol, or 1-octadecanol have been measured using a dynamic method. (Quinoline + benzene, +alkane, or +1-alkanol) systems were investigated using DISQUAC. The corresponding interaction parameters are reported. The model yields a good representation of molar excess Gibbs free energies, G{sup E}, molar excess enthalpies, H{sup E}, and of the (solid + liquid) equilibria, SLE. Interactional and structural effects were analysed comparing H{sup E} and the molar excess internal energy at constant volume, U{sub V}{sup E}. It was encountered that structural effects are very important in systems involving alkanes or 1-alkanols. Interactions between amine molecules are stronger in mixtures with quinoline than in those containing pyridine, which was ascribed to the higher polarizability of quinoline.

  5. Recyclable surfaces for amine conjugation chemistry via redox reaction

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Inseong; Yeo, Woon Seok [Dept. of Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul (Korea, Republic of); Bae, Se Won [Green Materials and Process Group, Research Institute of Sustainable Manufacturing System, Korea Institute of Industrial Technology, Cheonan (Korea, Republic of)

    2017-02-15

    In this study, we extended this strategy to present a switchable surface that allows surface functionalization and removal of functional groups repeatedly. The substrate presenting a benzoquinone acid group is first used to immobilize with an amine-containing (bio)molecule using well-known conjugation chemistry. The benzoquinone group is then converted to the corresponding hydroquinone by treating with a reducing agent. We have described a strategy for the dynamic control of surface properties with recyclability via a simple reduction/ oxidation reaction. A stimuli-responsive quinone derivative was harnessed for the repeated immobilization and release of (bio)molecules, and thus, for the repeated dynamic change of the surface properties according to the characteristics of the immobilized (bio)molecules.

  6. Synthesis of allyl amine on glass by continuous plasma

    International Nuclear Information System (INIS)

    Morales, J.; Olayo, R.; Vasquez, M.; OLayo, M.G.; Cruz, G.

    2003-01-01

    In this work the synthesis by plasma of thin films of polyallyl amine under continuous plasma conditions for possible use in biomaterials is presented. It is shown that the thickness of the film depends so much of the time of synthesis like of the used power. The polymers were analyzed by X-ray photoelectron spectroscopy (XPS) and angle of contact before and after of being immersed in distilled water by 10 days. The allylamine shows lost of nitrogen and an increase in the content of oxygen with the immersion time due to the interaction among the water and the polymer. The angle of contact shows an increase of approximately 10 degrees, what indicates a change in the surface energy of the polymer. (Author)

  7. Amine templated zinc phosphates phases for membrane separations

    Energy Technology Data Exchange (ETDEWEB)

    Nenoff, T.M.; Chavez, A.V.; Thoma, S.G.; Provencio, P. [Sandia National Labs., Albuquerque, NM (United States); Harrison, W.T.A. [Univ. of Western Australia, Nedlands (Australia); Phillips, M.L.F. [Gemfire Corp., Palo Alto, CA (United States)

    1998-08-01

    This research is focused on developing inorganic molecular sieve membranes for light gas separations such as hydrogen recovery and natural gas purification, and organic molecular separations, such as chiral enantiomers. The authors focus on zinc phosphates because of the ease in crystallization of new phases and the wide range of pore sizes and shapes obtained. With hybrid systems of zinc phosphate crystalline phases templated by amine molecules, the authors are interested in better understanding the association of the template molecules to the inorganic phase, and how the organic transfers its size, shape, and (in some cases) chirality to the bulk. Furthermore, the new porous phases can also be synthesized as thin films on metal oxide substrates. These films allow one to make membranes from organic/inorganic hybrid systems, suitable for diffusion experiments. Characterization techniques for both the bulk phases and the thin films include powder X-ray diffraction, TGA, Scanning Electron Micrograph (SEM) and Electron Dispersive Spectrometry (EDS).

  8. Un ticket pour la liberté

    Directory of Open Access Journals (Sweden)

    Nabil Mouline

    2014-07-01

    Full Text Available Pour diverses raisons, l’industrie cinématographique égyptienne a connu des changements profonds au début des années 2000. L’une des conséquences les plus palpables a été la production de manière volontaire ou involontaire de films contestataires dans la mesure où ils essaient de remettre en cause le discours dominant et de lever le tabou sur plusieurs questions sociopolitiques. Cela a fait du produit filmique non seulement un document d’archive qui reflète l’état de la société mais également un outil efficace de soft influence et de mobilisation qui a participé à la création d’une communauté imaginée dont une partie est passée à l’action le 25 janvier 2011. C’est l’ambition de cet article que de lever le voile sur ce double rôle du cinéma entre 2001 et 2010 en s’appuyant sur un large échantillon de films à grand succès.

  9. Strategies facilitant les tests en pre-certification pour la robustesse a l'egard des radiations =

    Science.gov (United States)

    Souari, Anis

    Les effets des radiations cosmiques sur l'electronique embarquee preoccupent depuis. quelques decennies les chercheurs interesses par la robustesse des circuits integres. Plusieurs. recherches ont ete menees dans cette direction, principalement pour les applications spatiales. ou l’environnement de leur deploiement est hostile. En effet, ces environnements sont denses. en termes de particules qui, lorsqu’elles interagissent avec les circuits integres, peuvent. mener a leur dysfonctionnement, voir meme a leur destruction. De plus, les effets des. radiations s’accentuent pour les nouvelles generations des circuits integres ou la diminution. de la taille des transistors et l’augmentation de la complexite de ces circuits augmentent la. probabilite d’apparition des anomalies et par consequence la croissance des besoins de test. L’expansion de l’electronique grand public (commercial off-the-shelf, COTS) et l’adoption. de ces composants pour des applications critiques comme les applications avioniques et. spatiales incitent egalement les chercheurs a doubler les efforts de verification de la fiabilite. de ces circuits. Les COTS, malgre leurs meilleures caracteristiques en comparaison avec les. circuits durcis tolerants aux radiations qui sont couteux et en retard en termes de technologie. utilisee, sont vulnerables aux radiations. Afin d’ameliorer la fiabilite de ces circuits, une evaluation de leur vulnerabilite dans les. differents niveaux d’abstraction du flot de conception est recommandee. Ceci aide les. concepteurs a prendre les mesures de mitigation necessaires sur le design au niveau. d’abstraction en question. Enfin, afin de satisfaire les exigences de tolerance aux pannes, des. tests tres couteux de certification, obtenus a l’aide de bombardement de particules (protons, neutrons, etc.), sont necessaires. Dans cette these, nous nous interessons principalement a definir une strategie de precertification

  10. Control of biogenic amines in food--existing and emerging approaches.

    Science.gov (United States)

    Naila, Aishath; Flint, Steve; Fletcher, Graham; Bremer, Phil; Meerdink, Gerrit

    2010-09-01

    Biogenic amines have been reported in a variety of foods, such as fish, meat, cheese, vegetables, and wines. They are described as low molecular weight organic bases with aliphatic, aromatic, and heterocyclic structures. The most common biogenic amines found in foods are histamine, tyramine, cadaverine, 2-phenylethylamine, spermine, spermidine, putrescine, tryptamine, and agmatine. In addition octopamine and dopamine have been found in meat and meat products and fish. The formation of biogenic amines in food by the microbial decarboxylation of amino acids can result in consumers suffering allergic reactions, characterized by difficulty in breathing, itching, rash, vomiting, fever, and hypertension. Traditionally, biogenic amine formation in food has been prevented, primarily by limiting microbial growth through chilling and freezing. However, for many fishing based subsistence populations, such measures are not practical. Therefore, secondary control measures to prevent biogenic amine formation in foods or to reduce their levels once formed need to be considered as alternatives. Such approaches to limit microbial growth may include hydrostatic pressures, irradiation, controlled atmosphere packaging, or the use of food additives. Histamine may potentially be degraded by the use of bacterial amine oxidase or amine-negative bacteria. Only some will be cost-effective and practical for use in subsistence populations.

  11. Control of Biogenic Amines in Food—Existing and Emerging Approaches

    Science.gov (United States)

    Naila, Aishath; Flint, Steve; Fletcher, Graham; Bremer, Phil; Meerdink, Gerrit

    2010-01-01

    Biogenic amines have been reported in a variety of foods, such as fish, meat, cheese, vegetables, and wines. They are described as low molecular weight organic bases with aliphatic, aromatic, and heterocyclic structures. The most common biogenic amines found in foods are histamine, tyramine, cadaverine, 2-phenylethylamine, spermine, spermidine, putrescine, tryptamine, and agmatine. In addition octopamine and dopamine have been found in meat and meat products and fish. The formation of biogenic amines in food by the microbial decarboxylation of amino acids can result in consumers suffering allergic reactions, characterized by difficulty in breathing, itching, rash, vomiting, fever, and hypertension. Traditionally, biogenic amine formation in food has been prevented, primarily by limiting microbial growth through chilling and freezing. However, for many fishing based subsistence populations, such measures are not practical. Therefore, secondary control measures to prevent biogenic amine formation in foods or to reduce their levels once formed need to be considered as alternatives. Such approaches to limit microbial growth may include hydrostatic pressures, irradiation, controlled atmosphere packaging, or the use of food additives. Histamine may potentially be degraded by the use of bacterial amine oxidase or amine-negative bacteria. Only some will be cost-effective and practical for use in subsistence populations. PMID:21535566

  12. Influence of fertilisation with foliar urea on the content of amines in wine.

    Science.gov (United States)

    Ancín-Azpilicueta, C; Nieto-Rojo, R; Gómez-Cordón, J

    2011-01-01

    Amines are substances that could cause toxic effects in the consumer. The concentration of amines in wine depends on different factors such as grape variety, vinification conditions and nitrogen fertilisation of the vines. The aim of this work was to study the influence of the application of foliar urea on the concentration of amines in wine. To carry out the study, grapevines of Tempranillo variety were used. These grapevines were treated with foliar urea at two different concentrations: 2 and 4 kg N ha(-1). Treatment with foliar urea significantly increased (p wines compared with the control sample (65% in the treatment with 2 kg N ha(-1) and 93% in the treatment with 4 kg N ha(-1)), reaching higher concentrations than the threshold level where it could provoke toxic effects in the consumer (8-20 mg l(-1)). On the other hand, treatment with foliar urea did not increase the concentrations of other amines which could be toxic such as tyramine or phenylethylamine, nor amines such as putrescine which could enhance the toxic effect of histamine. In the case of the volatile amines containing secondary amine groups, the concentration of pirrolidine increased by 37% after treatment with 2 kg N ha(-1) and 61% after treatment with 4 kg N ha(-1).

  13. Visible Light Induced Green Transformation of Primary Amines to Imines Using a Silicate Supported Anatase Photocatalyst

    Directory of Open Access Journals (Sweden)

    Sifani Zavahir

    2015-01-01

    Full Text Available Catalytic oxidation of amine to imine is of intense present interest since imines are important intermediates for the synthesis of fine chemicals, pharmaceuticals, and agricultural chemicals. However, considerable efforts have been made to develop efficient methods for the oxidation of secondary amines to imines, while little attention has until recently been given to the oxidation of primary amines, presumably owing to the high reactivity of generated imines of primary amines that are easily dehydrogenated to nitriles. Herein, we report the oxidative coupling of a series of primary benzylic amines into corresponding imines with dioxygen as the benign oxidant over composite catalysts of TiO2 (anatase-silicate under visible light irradiation of λ > 460 nm. Visible light response of this system is believed to be as a result of high population of defects and contacts between silicate and anatase crystals in the composite and the strong interaction between benzylic amine and the catalyst. It is found that tuning the intensity and wavelength of the light irradiation and the reaction temperature can remarkably enhance the reaction activity. Water can also act as a green medium for the reaction with an excellent selectivity. This report contributes to the use of readily synthesized, environmentally benign, TiO2 based composite photocatalyst and solar energy to realize the transformation of primary amines to imine compounds.

  14. Amine oxidases as important agents of pathological processes of rhabdomyolysis in rats.

    Science.gov (United States)

    Gudkova, O O; Latyshko, N V; Shandrenko, S G

    2016-01-01

    In this study we have tested an idea on the important role of amine oxidases (semicarbazide-sensitive amine oxidase, diamine oxidase, polyamine oxidase) as an additional source of oxidative/carbonyl stress under glycerol-induced rhabdomyolysis, since the enhanced formation of reactive oxygen species and reactive carbonyl species in a variety of tissues is linked to various diseases. In our experiments we used the sensitive fluorescent method devised for estimation of amine oxidases activity in the rat kidney and thymus as targeted organs under rhabdomyolysis. We have found in vivo the multiple rises in activity of semicarbazide-sensitive amine oxidase, diamine oxidase, polyamine oxidase (2-4.5 times) in the corresponding cell fractions, whole cells or their lysates at the 3-6th day after glycerol injection. Aberrant antioxidant activities depended on rhabdomyolysis stage and had organ specificity. Additional treatment of animals with metal chelator ‘Unithiol’ adjusted only the activity of antioxidant enzymes but not amine oxidases in both organs. Furthermore the in vitro experiment showed that Fenton reaction (hydrogen peroxide in the presence of iron) products alone had no effect on semicarbazide-sensitive amine oxidase activity in rat liver cell fraction whereas supplementation with methylglyoxal resulted in its significant 2.5-fold enhancement. Combined action of the both agents had additive effect on semicarbazide-sensitive amine oxidase activity. We can assume that biogenic amine and polyamine catabolism by amine oxidases is upregulated by oxidative and carbonyl stress factors directly under rhabdomyolysis progression, and the increase in catabolic products concentration contributes to tissue damage in glycerol-induced acute renal failure and apoptosis stimulation in thymus.

  15. C(sp3)-H Azidation Reaction: A Protocol for Preparation of Aminals.

    Science.gov (United States)

    Dong, Jianyang; Xia, Qing; Yan, Changcun; Song, Hongjian; Liu, Yuxiu; Wang, Qingmin

    2018-03-22

    We report a protocol for the synthesis of N,N- and N,O-aminals via direct azidation of sp3 C-H bonds of substrates with an α-nitrogen or α-oxygen atom. A broad range of tetrahydroisoquinolines, tetrahydro-β-carbolines, and cyclic benzyl ethers gave high yields under mild conditions. The protocol could be carried out on a gram scale without a decrease in the yield, and the aminal products could be readily transformed into complex aminals.

  16. Boron-Catalyzed N-Alkylation of Amines using Carboxylic Acids.

    Science.gov (United States)

    Fu, Ming-Chen; Shang, Rui; Cheng, Wan-Min; Fu, Yao

    2015-07-27

    A boron-based catalyst was found to catalyze the straightforward alkylation of amines with readily available carboxylic acids in the presence of silane as the reducing agent. Various types of primary and secondary amines can be smoothly alkylated with good selectivity and good functional-group compatibility. This metal-free amine alkylation was successfully applied to the synthesis of three commercial medicinal compounds, Butenafine, Cinacalcet. and Piribedil, in a one-pot manner without using any metal catalysts. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Microwave-assisted one step synthesis of 8-arylmethyl-9H-purin-6-amines.

    Science.gov (United States)

    Tao, Hui; Kang, Yanlong; Taldone, Tony; Chiosis, Gabriela

    2009-01-15

    Molecular chaperone heat shock protein 90 (Hsp90) is an important target in cancer and neurodegenerative diseases, and has rapidly become the focus of several drug discovery efforts. Among small molecule Hsp90 inhibitors with clinical applicability are derivatives of 8-arylmethyl-9H-purin-6-amine class. Here we report the use of microwave-assisted chemistry for the successful one-pot delivery of 8-arylmethyl-9H-purin-6-amines. We discuss the applicability as well as the limitations of this method towards the creation of a large chemical diversity in the 8-arylmethyl-9H-purin-6-amine series.

  18. The tandem Mannich-electrophilic amination reaction: a versatile platform for fluorescent probing and labeling.

    Science.gov (United States)

    Sączewski, Jarosław; Hinc, Krzysztof; Obuchowski, Michał; Gdaniec, Maria

    2013-08-26

    Tandem fluorogenic reaction: A new platform for the direct, selective and sensitive detection of formaldehyde and/or secondary aliphatic amines, based on a tandem Mannich-electrophilic amination reaction, is described. Biological applications of hydrophilic, water-soluble fluorescent 2,2-dialkyl-2,3-dihydro-[1,2,4]triazolo[4,3-a]pyridin-2-ium-8-carboxylates (Safarinium P probes) are exemplified by labeling of the amine-containing Ac-AKF-NH2 peptide and Bacillus subtilis spores in aqueous solution. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Electrochemical C-H Amination by Cobalt Catalysis in a Renewable Solvent.

    Science.gov (United States)

    Sauermann, Nicolas; Mei, Ruhuai; Ackermann, Lutz

    2018-03-06

    Syntheses of substituted anilines primarily rely on palladium-catalyzed coupling chemistry with prefunctionalized aryl electrophiles. While oxidative aminations have emerged as powerful alternatives, they largely produce undesired metal-containing by-products in stoichiometric quantities. In contrast, described herein is the unprecedented electrochemical C-H amination by cobalt-catalyzed C-H activation. The environmentally benign electrocatalysis avoids stoichiometric metal oxidants, can be conducted under ambient air, and employs a biomass-derived, renewable solvent for sustainable aminations in an atom- and step-economical manner with H 2 as the sole byproduct. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. High production volume chemical Amine Oxide [C8-C20] category environmental risk assessment

    DEFF Research Database (Denmark)

    Sanderson, Hans; Tibazarwa, Caritas; Greggs, William

    2009-01-01

    and personal care products. Given the lack of persistence or bioaccumulation, and the low likelihood of these chemicals partitioning to soil, the focus of the environmental assessment is on the aquatic environment. In the United States, the E-FAST model is used to estimate effluent concentrations in the United......An environmental assessment of amine oxides has been conducted under the OECD SIDS High Production Volume (HPV) Program via the Global International Council of Chemical Associations (ICCA) Amine Oxides Consortium. Amine oxides are primarily used in conjunction with surfactants in cleaning...

  1. A Process Concept for High-Purity Production of Amines by Transaminase-Catalyzed Asymmetric Synthesis: Combining Enzyme Cascade and Membrane-Assisted ISPR

    DEFF Research Database (Denmark)

    Börner, Tim; Rehn, Gustav; Grey, Carl

    2015-01-01

    For the amine transaminase (ATA)-catalyzed synthesis of chiral amines, the choice of donor substrate is of high importance for reaction and process design. Alanine was investigated as an amine donor for the reductive amination of a poorly water-soluble ketone (4-phenyl-2-butanone) in a combined...

  2. Deux comparatismes pour une anthropologie historique

    Directory of Open Access Journals (Sweden)

    Pierre-Olivier Dittmar

    2010-06-01

    Full Text Available Malgré des appels répétés depuis plus d’un siècle de la part des historiens, le comparatisme, qui est un élément majeur de l’anthropologie, demeure très peu pratiqué. Ce rejet est ici analysé comme un refus d’une quête des invariants de l’homme qui aboutirait à des résultats an-historiques. Un autre comparatisme est cependant possible, qui instrumentalise la confrontation des univers pour mieux relever les différences. C’est les conditions et les avantages d’une telle pratique qui sont ici exposés, à partir de l’exemple des tabous alimentaires.Despite the repeated calls by some historians for more than a century, many seldom practice a major element of anthropology: comparativism. This paper will analyze this rejection as a refusal to investigate the constants of the human experience that lead to a-historical conclusions. However, another kind of comparativism is possible, one that examines the contrast between cultures in order to better understand their differences. Using the case of dietary taboos, this paper will look at the conditions and advantages of such a practice.Nonostante i molteplici appelli da più di un secolo da parte degli storici, il comparatismo, che costituisce un elemento fondamentale dell’antropologia, è ancora oggi troppo poco spesso praticato. Si proporrà di interpretare questo rifiuto come un rifiuto della ricerca di invarianti umane che condurrebbe a risultati a-storici. Un’altra forma di comparatismo è nondimeno possibile, una forma precisamente che ricorre al confronto di universi diversi per meglio comprenderne le difference reciproche. L’articolo espone le condizioni e i vantaggi di questa metodologia di ricerca, a partire dall’esempio degli interdetti alimentari.

  3. Kenya : tous les projets | Page 3 | CRDI - Centre de recherches pour ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le réseau GEOHealth d'Afrique orientale pour la prévention des risques pour la santé des travailleurs et la salubrité environnementale. Projet. La charge de morbidité résultant des dangers pour la santé ... Una Hakika : Porter à grande échelle les solutions numériques pour la gestion des conflits au Kenya et en Birmanie.

  4. Accroître les occasions d'affaire pour les jeunes Africains dans les ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le projet permettra d'élaborer et de mettre en oeuvre des méthodes pour répertorier les marchés de produits agricoles précis et pour trouver des possibilités d'activités agroalimentaires viables pour les jeunes. L'équipe de projet recrutera des jeunes possédant des aptitudes pour l'entrepreneuriat et leur enseignera les ...

  5. Preparation of polymeric pour point depressants for shale oil

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Tingyn; Wang, Jilin [Liaoning Univ. of Petroleum and Chemical Technology, Fushun (China). Dept. of Petrochemical Technology; Jin, Jingsen [Petrochina Fushun Petrochemical Company Refinery No. 2 (China)

    2006-06-15

    The melt esterification of acrylic acid and higher alcohols without solvent is carried out and the effects of factors on the production efficiency of acrylic higher alcohol ester are investigated. Optimum reaction conditions are obtained at molar ratio of acrylic acid to higher alcohol 1.2:1.0 and reflux time 7 h at 110-140{sup o}C in stepwise heating. At this point the acrylic higher alcohol ester will be polymerized with maleic anhydride, phenylethylene, and vinyl acetate, and formed into four components. Copolymer shale oil pour point depressant and the polymerization condition are also studied by orthogonal method. The effect of pour point depressants is best when the monomer molar ratio is 8:1:1:1 at 80{sup o}C for 8 h for reflux and the benzoyl peroxide is added. The pour point of Fushun shale oil reduces by 9{sup o}C when only 0.5% copolymer is added. (Author)

  6. Contribution to the study of the leukemia potential of radiation used in radio-diagnostic in children: statistical study of the main radiological examinations according to age and sex (1963); Contribution a l'etude du pouvoir leukemogene des radiations utilisees en radiodiagnostic chez l'enfant: etude statistique des principaux examens radiologiques suivant l'age et le sexe

    Energy Technology Data Exchange (ETDEWEB)

    Larcher, B. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1963-06-15

    With a view to discovering whether low irradiation doses are liable to increase the incidence of leukemia or cancer amongst people exposed to this risk, an enquiry, has been undertaken into the distribution according to age and to sex of 13,596 important radiological examinations carried out in radio-pediatric departments from 1953 to 1961, a population structure study essential for choosing the group studied and the comparison group. This survey will be used as the basis for the constitution of a population whose pathology will be examined with great care. The main conclusion resulting from this enquiry is that the frequency of digestive and urinary examinations is very high in babies of under one year old and higher in boys than in girls. (author) [French] Dans le but de determiner si les faibles doses d'irradiations sont susceptibles d'augmenter le taux de leucemies ou de cancer dans les populations exposees a ce risque, une enquete a ete faite sur la repartition par age et par sexe de 13596 examens radiologiques importants effectues dans des services de radiopediatrie de 1953 a 1961, elude de la structure de la population necessaire pour choisir le groupe etudie et le groupe temoin. Ce releve sert de base a la constitution d'une population dont la pathologie sera recherchee avec soin. De cette enquete, il ressort essentiellement que la frequence des examens digestifs et urinaires est tres elevee chez les nourrissons ages de moins d'un an, et plus elevee chez les garcons que chez les filles. (auteur)

  7. Amine Chemistry at Aqueous Interfaces: The Study of Organic Amines in Neutralizing Acidic Gases at an Air/Water Surface Using Vibrational Sum Frequency Spectroscopy

    Science.gov (United States)

    McWilliams, L.; Wren, S. N.; Valley, N. A.; Richmond, G.

    2014-12-01

    Small organic bases have been measured in atmospheric samples, with their sources ranging from industrial processing to animal husbandry. These small organic amines are often highly soluble, being found in atmospheric condensed phases such as fogwater and rainwater. Additionally, they display acid-neutralization ability often greater than ammonia, yet little is known regarding their kinetic and thermodynamic properties. This presentation will describe the molecular level details of a model amine system at the vapor/liquid interface in the presence of acidic gas. We find that this amine system shows very unique properties in terms of its bonding, structure, and orientation at aqueous surfaces. The results of our studies using a combination of computation, vibrational sum frequency spectroscopy, and surface tension will report the properties inherent to these atmospherically relevant species at aqueous surfaces.

  8. Analysis of amines by pH-Metrie in organic media

    International Nuclear Information System (INIS)

    Hamidi, A.; Elias, Abdelhamid; Achache, M.; Didi, M.

    1999-01-01

    Amines with long hydro carbonic strength and principally Trioclkylamines, are characterised by an important complexation mechanism for certain metals. This is the case for trioctylamine (TOA) which is very used in purification and uranium recovery from certain ores (1,2). This substance is generally found mixed with mono and di-octyl amines in commercial products and in synthesis mixtures. The purpose of this work is to develop a pH titration method in an organic media for a mixture consisted of mono, di and tri octyl amines (MOA, DOA et TOA). Adequate operating analysis condition have been proposed, based on intrinsic chemical properties for each precipitated substances (3,4). The obtained results show that this technique is recommended for qualitative and quantitative analysis of precipitated amines mixtures. The method is reproducible and the detection limit can reach 0,0001 molar

  9. Effect of Amine Adlayer on Electrochemical Uric Acid Sensor Conducted on Electrochemically Reduced Graphene Oxide

    International Nuclear Information System (INIS)

    Park, Sumi; Kim, Kyuwon

    2016-01-01

    The electrochemical biosensing efficiency of uric acid (UA) detection on an electrochemically reduced graphene oxide (ERGO)-decorated electrode surface was studied by using various amine linkers used to immobilize ERGO. The amine linkers aminoethylphenyldiazonium , 2,2'-(ethylenedioxy)bis(ethylamine), 3-aminopro-pyltriethoxysilane, and polyethyleneimine were coated on indium-tin-oxide electrode surfaces through chemical or electrochemical deposition methods. ERGO-decorated surfaces were prepared by the electrochemical reduction of graphene oxide (GO), which was immobilized on the amine-coated electrode surfaces through the electrostatic interaction between GO and the ammonium ion of the linker on the surface. We monitored the sensing results of electrochemical UA detection with differential pulse voltammetry. The ERGO-modified surface presented electrocatalytic oxidation of UA and ascorbic acid. Among the different amines tested, 3-aminopropyltriethoxysilane provided the best biosensing performance in terms of sensitivity and reproducibility.

  10. Effect of Amine Adlayer on Electrochemical Uric Acid Sensor Conducted on Electrochemically Reduced Graphene Oxide

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sumi; Kim, Kyuwon [Incheon National University, Incheon (Korea, Republic of)

    2016-03-15

    The electrochemical biosensing efficiency of uric acid (UA) detection on an electrochemically reduced graphene oxide (ERGO)-decorated electrode surface was studied by using various amine linkers used to immobilize ERGO. The amine linkers aminoethylphenyldiazonium , 2,2'-(ethylenedioxy)bis(ethylamine), 3-aminopro-pyltriethoxysilane, and polyethyleneimine were coated on indium-tin-oxide electrode surfaces through chemical or electrochemical deposition methods. ERGO-decorated surfaces were prepared by the electrochemical reduction of graphene oxide (GO), which was immobilized on the amine-coated electrode surfaces through the electrostatic interaction between GO and the ammonium ion of the linker on the surface. We monitored the sensing results of electrochemical UA detection with differential pulse voltammetry. The ERGO-modified surface presented electrocatalytic oxidation of UA and ascorbic acid. Among the different amines tested, 3-aminopropyltriethoxysilane provided the best biosensing performance in terms of sensitivity and reproducibility.

  11. α,β-Unsaturated imines via Ru-catalyzed coupling of allylic alcohols and amines.

    Science.gov (United States)

    Rigoli, Jared W; Moyer, Sara A; Pearce, Simon D; Schomaker, Jennifer M

    2012-03-07

    A convenient synthesis of α,β-unsaturated imines requiring only an allylic alcohol, an amine and a Ru catalyst has been developed. The use of large excesses of oxidant and the purification of sensitive intermediates can be avoided.

  12. on the elementary steps of acid zeolite catalyzed amination of light alcohols

    NARCIS (Netherlands)

    Veefkind, V.A.; Lercher, J.A.

    1999-01-01

    Potential elementary reaction steps in solid acid catalyzed amination of light alcohols are critically compared using hydrogen mordenite as (model) catalyst and the open mechanistic questions have been addressed. Transient kinetic experiments combined with in situ infrared spectroscopy and isotopic

  13. Quantitation of buried contamination by use of solvents. [degradation of silicone polymers by amine solvents

    Science.gov (United States)

    Pappas, S. P.; Hsiao, Y. C.; Hill, L. W.

    1973-01-01

    Spore recovery form cured silicone potting compounds using amine solvents to degrade the cured polymers was investigated. A complete list of solvents and a description of the effect of each on two different silicone polymers is provided.

  14. Electrochemical release of amine molecules from carbamate-based, electroactive self-assembled monolayers.

    Science.gov (United States)

    Hong, Daewha; Kang, Kyungtae; Hong, Seok-Pyo; Shon, Hyun Kyong; Son, Jin Gyeong; Lee, Tae Geol; Choi, Insung S

    2012-01-10

    In this paper, carbamate-based self-assembled monolayers (SAMs) of alkanethiolates on gold were suggested as a versatile platform for release of amine-bearing molecules in response to the electrical signal. The designed SAMs underwent the electrochemical oxidation on the gold surface with simultaneous release of the amine molecules. The synthesis of the thiol compounds was achieved by coupling isocyanate-containing compounds with hydroquinone. The electroactive thiol was mixed with 11-mercaptoundecanol [HS(CH(2))(11)OH] to form a mixed monolayer, and cyclic votammetry was used for the characterization of the release behaviors. The mixed SAMs showed a first oxidation peak at +540 mV (versus Ag/AgCl reference electrode), indicating the irreversible conversion from carbamate to hydroquinone groups with simultaneous release of the amine molecules. The analysis of ToF-SIMS further indicated that the electrochemical reaction on the gold surface successfully released amine molecules.

  15. Ni-Catalyzed Carbon-Carbon Bond-Forming Reductive Amination.

    Science.gov (United States)

    Heinz, Christoph; Lutz, J Patrick; Simmons, Eric M; Miller, Michael M; Ewing, William R; Doyle, Abigail G

    2018-02-14

    This report describes a three-component, Ni-catalyzed reductive coupling that enables the convergent synthesis of tertiary benzhydryl amines, which are challenging to access by traditional reductive amination methodologies. The reaction makes use of iminium ions generated in situ from the condensation of secondary N-trimethylsilyl amines with benzaldehydes, and these species undergo reaction with several distinct classes of organic electrophiles. The synthetic value of this process is demonstrated by a single-step synthesis of antimigraine drug flunarizine (Sibelium) and high yielding derivatization of paroxetine (Paxil) and metoprolol (Lopressor). Mechanistic investigations support a sequential oxidative addition mechanism rather than a pathway proceeding via α-amino radical formation. Accordingly, application of catalytic conditions to an intramolecular reductive coupling is demonstrated for the synthesis of endo- and exocyclic benzhydryl amines.

  16. Process considerations for the asymetric synthesis of chiral amines using transaminases

    DEFF Research Database (Denmark)

    Tufvesson, Pär; Lima Ramos, Joana; Jensen, Jacob Skibsted

    2011-01-01

    Biocatalytic transamination is being established as key tool for the production of chiral amine pharmaceuticals and precursors due to its excellent enantioselectivity as well as green credentials. Recent examples demonstrate the potential for developing economically competitive processes using a ...

  17. Development of an expression macroarray for amine metabolism-related genes.

    Science.gov (United States)

    Chaves, P; Correa-Fiz, F; Melgarejo, E; Urdiales, J L; Medina, M A; Sánchez-Jiménez, F

    2007-08-01

    Cationic amino acids are the precursors of biogenic amines, histamine from histidine, and putrescine, spermidine and spermine from arginine/ornithine (and methionine), as well as nitric oxide. These amines play important biological roles in inter- and intracellular signaling mechanisms related to inflammation, cell proliferation and neurotransmission. Biochemical and epidemiological relationships between arginine-derived products and histamine have been reported to play important roles in physiopathological problems. In this communication, we describe the construction of an expression macroarray containing more than 30 human probes for most of the key proteins involved in biogenic amines metabolisms, as well as other inflammation- and proliferation-related probes. The array has been validated on human mast HMC-1 cells. On this model, we have got further support for an inverse correlation between polyamine and histamine synthesis previously observed on murine basophilic models. These tools should also be helpful to understand the amine roles in many other inflammatory and neoplastic pathologies.

  18. Biogenic amines degradation by malolactic bacteria: towards a potential application in wine

    Directory of Open Access Journals (Sweden)

    Vittorio eCapozzi

    2012-04-01

    Full Text Available Biogenic amines in wine represent a toxicological risk for the health of the consumer, with several trade implications. In this study 26 strains of Lactobacillus plantarum were analysed for their ability to degrade biogenic amines commonly found during wine fermentation. Two strains of L. plantarum were selected in reason of their ability to degrade putrescine and tyramine. The degradation was assessed in vitro, both in presence of the biogenic amines and in presence of the specific chemical precursor and of producer bacteria. The two L. plantarum biotypes were found capable to work synergically. In addition, the survival in wine-like medium and the aptitude to degrade malic acid after alcoholic fermentation of the selected L. plantarum strains was analysed. Our results suggest the potential application of wine L. plantarum strains to design malolactic starter cultures able to degrade biogenic amines in wine.

  19. Purification of wet process phosphoric acid by solvent extraction with long-chain aliphatic amines

    International Nuclear Information System (INIS)

    Stenstroem, S.

    1986-09-01

    Purification of phosphoric acid by solvent extraction with long-chain aliphatic amines is investigated. Extraction of cadmium is extensively examined regarding the importance of the aqueous phase, the diluent and the amine. The solubility of tri-n-octyl-amine is determined in water and phosphoric acid solutions. Properties of valuable constituent such as uranium and yttrium are screened. Modelling of the system is performed by adapting Bromley's model for electrolytes to the different dissociation/association equilibria in the aqueous phase. In the organic phase simple expressions are used for the non-ideal behaviour. Amine-acid equilibria are investigated for all acids present in industrial phosphoric acid. New extraction constants are calculated for phosphoric and hydro- fluosilic acid. Calculations are compared with experiments both from binary and multicomponent acid mixtures

  20. The stability study of myristyl dimethyl amine oxide as an amphoteric ...

    African Journals Online (AJOL)

    The stability study of myristyl dimethyl amine oxide as an amphoteric surfactant in strong oxidant media containing 5 % m/m sodium hypochlorite through measurement of decomposing rate using high performance liquid chromatography and two phase titration.

  1. Cycle water chemistry based on film forming amines at power plants: evaluation of technical guidance documents

    Science.gov (United States)

    Dyachenko, F. V.; Petrova, T. I.

    2017-11-01

    Efficiency and reliability of the equipment in fossil power plants as well as in combined cycle power plants depend on the corrosion processes and deposit formation in steam/water circuit. In order to decrease these processes different water chemistries are used. Today the great attention is being attracted to the application of film forming amines and film forming amine products. The International Association for the Properties of Water and Steam (IAPWS) consolidated the information from all over the World, and based on the research studies and operating experience of researchers and engineers from 21 countries, developed and authorized the Technical Guidance Document: “Application of Film Forming Amines in Fossil, Combined Cycle, and Biomass Power Plants” in 2016. This article describe Russian and International technical guidance documents for the cycle water chemistries based on film forming amines at fossil and combined cycle power plants.

  2. identification de caractéristiques agronomiques pour le diagnostic

    African Journals Online (AJOL)

    ACSS

    La régénération des vieux vergers de cacaoyers (Theobrama cacao L.) est une des stratégies mises en place en. Côte d'Ivoire pour assurer une production durable de cacao. Une étude a été conduite en vue d'élaborer un guide pour réaliser un diagnostic rapide et adéquat des vergers et prendre la bonne décision de ...

  3. Etude et simulation des techniques de multiplexage OFDM pour une ...

    African Journals Online (AJOL)

    La simulation de ce modèle a révélé que, pour un même RSB de 20 dB, la technique ACO-OFDM (présentant un TEB de 0.0083) est moins sensible au bruit que la technique DCO-OFDM (dont le TEB est de 0.3413). Il est aussi remarqué que, pour un même RSB, l'implémentation de la DFT en matière de génération de ...

  4. Ethiopia : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le réseau GEOHealth d'Afrique orientale pour la prévention des risques pour la santé des travailleurs et la salubrité environnementale. Projet. La charge de morbidité ... Projet. L'Éthiopie réalise des progrès en ce qui concerne la gestion de l'économie de marché. Date de début : 16 octobre 2013. End Date: 14 août 2015.

  5. Une charte éthique pour le Big Data

    OpenAIRE

    De Filippi, Primavera

    2013-01-01

    Des implications métiers, sans nul doute, pour ces obligations particulières qui doivent être respectées lors de l'utilisation de données provenant du Big Data, afin de garantir leur qualité, leur conservation et les conditions de leur réutilisation tant d'un point de vue technique, économique que légal. Une charte, outil pour nous y aider, vient d' être proposée.

  6. Emploi et croissance | Page 18 | CRDI - Centre de recherches pour ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Malgré les avancées importantes réalisées dans le domaine du développement au cours des dernières décennies, les pays en développement font toujours face à de grands défis dans leurs efforts pour lutter contre la pauvreté. Les programmes de transferts en espèces se révèlent des outils efficaces pour réduire la ...

  7. Rapid Cycle Amine (RCA) 3.0 System Development

    Science.gov (United States)

    Chullen, Cinda; Campbell, Colin; Papale, William; Hawes, Kevin; Wichowski, Robert

    2015-01-01

    The Rapid Cycle Amine (RCA) 3.0 system is currently under development by NASA, the Lyndon B. Johnson Space Center (JSC) in conjunction with United Technologies Corporation Aerospace Systems (UTAS). The RCA technology is a new carbon dioxide (CO2) and humidity removal system that has been baselined for the Advanced Extravehicular Mobility Unit (AEMU) Portable Life Support System. The evolution of the RCA development has progressed through several iterations of technology readiness levels including RCA 1.0, RCA 2.0, and RCA 3.0 test articles. The RCA is an advancement over currently technologies due to its unique regeneration capability. The RCA is capable of simultaneously removing CO2 and humidity from an influent air steam and subsequent regeneration when exposed to a vacuum source. The RCA technology uses two solid amine sorbent beds in an alternating fashion to adsorb CO2 and water (uptake mode) and desorb CO2 and water (regeneration mode) at the same time. The two beds operate in an efficient manner so that while one bed is in the uptake mode, the other is in the regeneration mode, thus continuously providing an on-service sorbent bed by which CO2 and humidity may be removed. The RCA 2.0 and 3.0 test articles were designed with a novel valve assembly which allows for switching between uptake and regeneration modes with only one moving part while minimizing gas volume losses to the vacuum source by means of an internal pressure equalization step during actuation. The RCA technology also is low power, small, and has performed extremely well in all development testing thus far. A final design was selected for the RCA 3.0, fabricated, assembled, and performance tested in 2014 with delivery to NASAJSC in January 2015. This paper will provide an overview on the RCA 3.0 system design and results of pre-delivery testing with references to the development of RCA 1.0 and RCA 2.0.

  8. Validation of an HPLC Analytical Method for Determination of Biogenic Amines in Agricultural Products and Monitoring of Biogenic Amines in Korean Fermented Agricultural Products.

    Science.gov (United States)

    Yoon, Hyeock; Park, Jung Hyuck; Choi, Ari; Hwang, Han-Joon; Mah, Jae-Hyung

    2015-09-01

    An HPLC analytical method was validated for the quantitative determination of biogenic amines in agricultural products. Four agricultural foods, including apple juice, Juk, corn oil and peanut butter, were selected as food matrices based on their water and fat contents (i.e., non-fatty liquid, non-fatty solid, fatty liquid and fatty solid, respectively). The precision, accuracy, recovery, limit of detection (LOD) and quantification (LOQ) were determined to test the validity of an HPLC procedure for the determination of biogenic amines, including tryptamine, β-phenylethylamine, putrescine, cadaverine, histamine, tyramine, spermidine and spermine, in each matrix. The LODs and LOQs for the biogenic amines were within the range of 0.01~0.10 mg/kg and 0.02~0.31 mg/kg, respectively. The relative standard deviation (RSD) of intraday for biogenic amine concentrations ranged from 1.86 to 5.95%, whereas the RSD of interday ranged from 2.08 to 5.96%. Of the matrices spiked with biogenic amines, corn oil with tyramine and Juk with putrescine exhibited the least accuracy of 84.85% and recovery rate of 89.63%, respectively, at the lowest concentration (10 mg/kg). Therefore, the validation results fulfilled AOAC criteria and recommendations. Subsequently, the method was applied to the analysis of biogenic amines in fermented agricultural products for a total dietary survey in Korea. Although the results revealed that Korean traditional soy sauce and Doenjang contained relatively high levels of histamine, the amounts are of no concern if these fermented agricultural products serve as condiments.

  9. Guide pour la conception des dispositifs de franchissement des barrages pour les poissons migrateurs

    Directory of Open Access Journals (Sweden)

    LARINIER M.

    1983-10-01

    Full Text Available L'auteur rappelle dans cette note les principes de base devant guider le projeteur lors de la conception des ouvrages de franchissement de barrages ou d'obstacles pour les poissons migrateurs. L'accent est mis sur l'importance de la situation et de l'attractivité de ces ouvrages. Les principes de fonctionnement et les critères de dimensionnement des différents types de passes (passes à bassins successifs, passes à ralentisseurs, écluses et ascenseurs sont évoqués. Dans la dernière partie sont recensés les éléments à prendre en compte lors de l'établissement d'un projet de passe.

  10. Quantification of amine functional groups and their influence on OM/OC in the IMPROVE network

    Science.gov (United States)

    Kamruzzaman, Mohammed; Takahama, Satoshi; Dillner, Ann M.

    2018-01-01

    Recently, we developed a method using FT-IR spectroscopy coupled with partial least squares (PLS) regression to measure the four most abundant organic functional groups, aliphatic C-H, alcohol OH, carboxylic acid OH and carbonyl C=O, in atmospheric particulate matter. These functional groups are summed to estimate organic matter (OM) while the carbon from the functional groups is summed to estimate organic carbon (OC). With this method, OM and OM/OC can be estimated for each sample rather than relying on one assumed value to convert OC measurements to OM. This study continues the development of the FT-IR and PLS method for estimating OM and OM/OC by including the amine functional group. Amines are ubiquitous in the atmosphere and come from motor vehicle exhaust, animal husbandry, biomass burning, and vegetation among other sources. In this study, calibration standards for amines are produced by aerosolizing individual amine compounds and collecting them on PTFE filters using an IMPROVE sampler, thereby mimicking the filter media and collection geometry of ambient standards. The moles of amine functional group on each standard and a narrow range of amine-specific wavenumbers in the FT-IR spectra (wavenumber range 1 550-1 500 cm-1) are used to develop a PLS calibration model. The PLS model is validated using three methods: prediction of a set of laboratory standards not included in the model, a peak height analysis and a PLS model with a broader wavenumber range. The model is then applied to the ambient samples collected throughout 2013 from 16 IMPROVE sites in the USA. Urban sites have higher amine concentrations than most rural sites, but amine functional groups account for a lower fraction of OM at urban sites. Amine concentrations, contributions to OM and seasonality vary by site and sample. Amine has a small impact on the annual average OM/OC for urban sites, but for some rural sites including amine in the OM/OC calculations increased OM/OC by 0.1 or more.

  11. Electronic and steric influences of pendant amine groups on the protonation of molybdenum bis (dinitrogen) complexes

    Energy Technology Data Exchange (ETDEWEB)

    Labios, Liezel A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Heiden, Zachariah M. [Washington State Univ., Pullman, WA (United States); Mock, Michael T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-05-04

    The synthesis of a series of PEtPNRR' (PEtPNRR' = Et₂PCH₂CH₂P(CH₂NRR')₂, R = H, R' = Ph or 2,4-difluorophenyl; R = R' = Ph or iPr) diphosphine ligands containing mono- and disubstituted pendant amine groups, and the preparation of their corresponding molybdenum bis(dinitrogen) complexes trans-Mo(N₂)₂(PMePh₂)₂(PEtPNRR') is described. In situ IR and multinuclear NMR spectroscopic studies monitoring the stepwise addition of (HOTf) to trans-Mo(N₂)₂(PMePh₂)₂(PEtPNRR') complexes in THF at -40 °C show that the electronic and steric properties of the R and R' groups of the pendant amines influence whether the complexes are protonated at Mo, a pendant amine, a coordinated N2 ligand, or a combination of these sites. For example, complexes containing mono-aryl substituted pendant amines are protonated at Mo and pendant amine to generate mono- and dicationic Mo–H species. Protonation of the complex containing less basic diphenyl-substituted pendant amines exclusively generates a monocationic hydrazido (Mo(NNH₂)) product, indicating preferential protonation of an N₂ ligand. Addition of HOTf to the complex featuring more basic diisopropyl amines primarily produces a monocationic product protonated at a pendant amine site, as well as a trace amount of dicationic Mo(NNH₂) product that contain protonated pendant amines. In addition, trans-Mo(N₂)₂(PMePh₂)₂(depe) (depe = Et₂PCH₂CH₂PEt₂) without a pendant amine was synthesized and treated with HOTf, generating a monocationic Mo(NNH₂) product. Protonolysis experiments conducted on select complexes in the series afforded trace amounts of NH₄⁺. Computational analysis of the series of trans-Mo(N₂)₂(PMePh₂)₂(PEtPNRR') complexes provides further insight into the proton affinity values of the metal center, N

  12. Synthesis of Guanidines via Reaction of Amines with Carbodiimides in the Presence of Ionic Liquid

    Directory of Open Access Journals (Sweden)

    Foad Shaghayeghi Toosi

    2016-01-01

    Full Text Available Different ionic liquids (ILs were synthesized and evaluated for the preparation of substituted guanidines from the reaction of amines and carbodiimides. 1-methylimidazolium tetrafluoroborate [HMIm]BF4 was found to be the best ionic liquid for this reaction. This IL acted as a promoter for the addition of primary and secondary amines to carbodiimides. By this efficient approach, various guanidines were prepared in excellent yields.

  13. Grafting of model primary amine compounds to cellulose nanowhiskers through periodate oxidation

    Science.gov (United States)

    Rajalaxmi Dash; Thomas Elder; Arthur Ragauskas

    2012-01-01

    This study demonstrates regioselective oxidation of cellulose nanowhiskers using 2.80–10.02 mmols of sodium periodate per 5 g of whiskers followed by grafting with methyl and butyl amines through a Schiff base reaction to obtain their amine derivatives in 80–90 % yield. We found a corresponding increase in carbonyl content (0.06–0.14 mmols/g) of the dialdehyde...

  14. Room-temperature Cu-catalyzed N-arylation of aliphatic amines in neat water.

    Science.gov (United States)

    Wang, Deping; Zheng, Yanwen; Yang, Min; Zhang, Fuxing; Mao, Fangfang; Yu, Jiangxi; Xia, Xiaohong

    2017-10-04

    A room-temperature and PTC-free copper-catalyzed N-arylation of aliphatic amines in neat water has been developed. Using a combination of CuI and 6,7-dihydroquinolin-8(5H)-one oxime as the catalyst and KOH as the base, a wide range of aliphatic amines are arylated with various aryl and heteroaryl halides to give the corresponding products in up to 95% yield.

  15. Amination of Aryl Halides and Esters Using Intensified Continuous Flow Processing

    Directory of Open Access Journals (Sweden)

    Thomas M. Kohl

    2015-09-01

    Full Text Available Significant process intensification of the amination reactions of aryl halides and esters has been demonstrated using continuous flow processing. Using this technology traditionally difficult amination reactions have been performed safely at elevated temperatures. These reactions were successfully conducted on laboratory scale coil reactor modules with 1 mm internal diameter (ID and on a preparatory scale tubular reactor with 6 mm ID containing static mixers.

  16. New procedure of selected biogenic amines determination in wine samples by HPLC

    Energy Technology Data Exchange (ETDEWEB)

    Piasta, Anna M.; Jastrzębska, Aneta, E-mail: aj@chem.uni.torun.pl; Krzemiński, Marek P.; Muzioł, Tadeusz M.; Szłyk, Edward

    2014-06-27

    Highlights: • We proposed new procedure for derivatization of biogenic amines. • The NMR and XRD analysis confirmed the purity and uniqueness of derivatives. • Concentration of biogenic amines in wine samples were analyzed by RP-HPLC. • Sample contamination and derivatization reactions interferences were minimized. - Abstract: A new procedure for determination of biogenic amines (BA): histamine, phenethylamine, tyramine and tryptamine, based on the derivatization reaction with 2-chloro-1,3-dinitro-5-(trifluoromethyl)-benzene (CNBF), is proposed. The amines derivatives with CNBF were isolated and characterized by X-ray crystallography and {sup 1}H, {sup 13}C, {sup 19}F NMR spectroscopy in solution. The novelty of the procedure is based on the pure and well-characterized products of the amines derivatization reaction. The method was applied for the simultaneous analysis of the above mentioned biogenic amines in wine samples by the reversed phase-high performance liquid chromatography. The procedure revealed correlation coefficients (R{sup 2}) between 0.9997 and 0.9999, and linear range: 0.10–9.00 mg L{sup −1} (histamine); 0.10–9.36 mg L{sup -1} (tyramine); 0.09–8.64 mg L{sup −1} (tryptamine) and 0.10–8.64 mg L{sup −1} (phenethylamine), whereas accuracy was 97%–102% (recovery test). Detection limit of biogenic amines in wine samples was 0.02–0.03 mg L{sup −1}, whereas quantification limit ranged 0.05–0.10 mg L{sup −1}. The variation coefficients for the analyzed amines ranged between 0.49% and 3.92%. Obtained BA derivatives enhanced separation the analytes on chromatograms due to the inhibition of hydrolysis reaction and the reduction of by-products formation.

  17. Three-component synthesis of alpha-branched amines under Barbier-like conditions.

    Science.gov (United States)

    Le Gall, Erwan; Haurena, Caroline; Sengmany, Stéphane; Martens, Thierry; Troupel, Michel

    2009-10-16

    An array of alpha-branched amines has been prepared by using an expedient three-component Mannich-type reaction among organic halides, aldehyde derivatives, and amines. The experimental procedure, which is characterized by its simplicity, employs zinc dust for the in situ generation of organozinc reagents. We show that this Barbier-like protocol constitutes a useful entry to diarylmethylamines, 1,2-diarylethylamines, alpha- or beta-amino esters, benzylamines, and beta-arylethylamines.

  18. Selective Hydrogenation of Nitriles to Primary Amines by using a Cobalt Phosphine Catalyst.

    Science.gov (United States)

    Adam, Rosa; Bheeter, Charles Beromeo; Cabrero-Antonino, Jose R; Junge, Kathrin; Jackstell, Ralf; Beller, Matthias

    2017-03-09

    A general procedure for the catalytic hydrogenation of nitriles to primary amines by using a non-noble metal-based system is presented. Co(acac) 3 in combination with tris[2-(dicyclohexylphosphino)ethyl]phosphine efficiently catalyzes the selective hydrogenation of a wide range of (hetero)aromatic and aliphatic nitriles to give the corresponding amines. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Analysis of Bacterial Vaginosis-Related Amines in Vaginal Fluid by Gas Chromatography and Mass Spectrometry

    OpenAIRE

    Wolrath, Helen; Forsum, Urban; Larsson, P. G.; Borén, Hans

    2001-01-01

    The presence of various amines in vaginal fluid from women with malodorous vaginal discharge has been reported before. The investigations have used several techniques to identify the amines. However, an optimized quantification, together with a sensitive analysis method in connection with a diagnostic procedure for vaginal discharge, including the syndrome of bacterial vaginosis, as defined by the accepted “gold standard,” has not been done before. We now report a sensitive gas chromatographi...

  20. Method for Preparation of Amides from Alcohols and Amines by Extrusion of Hydrogen

    DEFF Research Database (Denmark)

    2010-01-01

    The present invention relates to a method for preparation of carboxamides using alcohols and amines as starting materials in a dehydrogenative coupling reaction catalyzed by a ruthenium N-heterocyciic carbene (NHC) complex, which may be prepared in situ.......The present invention relates to a method for preparation of carboxamides using alcohols and amines as starting materials in a dehydrogenative coupling reaction catalyzed by a ruthenium N-heterocyciic carbene (NHC) complex, which may be prepared in situ....

  1. Expedient protocol for solid-phase synthesis of secondary and tertiary amines

    DEFF Research Database (Denmark)

    Olsen, Christian A; Witt, Matthias; Jaroszewski, Jerzy W

    2004-01-01

    [reaction: see text] An expedient solid-phase synthetic approach to secondary and tertiary amines was developed. The protocol employs conversion of resin-bound amino alcohols to the corresponding iodides, followed by iodide displacement with primary or secondary amines or with unprotected amino a...... alcohols. This two-step procedure, affording products in good to excellent yields, is suitable for solid-phase synthesis of polyamines....

  2. Kinetics and thermodynamics of amine and diamine signaling by a trifluoroacetyl azobenzene reporter group.

    Science.gov (United States)

    Mertz, Eric; Beil, James B; Zimmerman, Steven C

    2003-08-21

    [reaction: see text] (Trifluoroacetyl)azobenzene dyes were previously employed as amine reporter groups (chemosensors) in a dendrimer-based monomolecular imprinting system. Kinetic and binding studies with a range of amines and diamines show that the highly selective signaling observed for alkane diamines by these imprinted dendrimers arises from a kinetic effect due to intramolecular general base-catalyzed carbinolamine formation with the dye itself. The relationship between diamine structure and carbinolamine stability and rate of formation is described.

  3. Polymerized fatty acid amine derivatives useful as friction and wear-reducing additives

    Energy Technology Data Exchange (ETDEWEB)

    Coupland, K.; Smith, C.R.

    1981-02-10

    A hydrocarbon composition having a major portion of a hydrocarbon preferably a lubricating oil such as mineral oil and at least a friction-reducing amount usually 0.01 to 10 weight percent of an amine or amine derivative of a hydrocarbon-soluble polymerized fatty acid e.g. a dimeramine derived from a dicarboxylic acid containing at least 12 carbon atoms such as 9(10)-carboxy stearic acid has improved antifriction and flue economy properties.

  4. Preparation of aminated chitosan/alginate scaffold containing halloysite nanotubes with improved cell attachment.

    Science.gov (United States)

    Amir Afshar, Hamideh; Ghaee, Azadeh

    2016-10-20

    The chemical nature of biomaterials play important role in cell attachment, proliferation and migration in tissue engineering. Chitosan and alginate are biodegradable and biocompatible polymers used as scaffolds for various medical and clinical applications. Amine groups of chitosan scaffolds play an important role in cell attachment and water adsorption but also associate with alginate carboxyl groups via electrostatic interactions and hydrogen bonding, consequently the activity of amine groups in the scaffold decreases. In this study, chitosan/alginate/halloysite nanotube (HNTs) composite scaffolds were prepared using a freeze-drying method. Amine treatment on the scaffold occurred through chemical methods, which in turn caused the hydroxyl groups to be replaced with carboxyl groups in chitosan and alginate, after which a reaction between ethylenediamine, 1-ethyl-3,(3-dimethylaminopropyl) carbodiimide (EDC) and scaffold triggered the amine groups to connect to the carboxyl groups of chitosan and alginate. The chemical structure, morphology and mechanical properties of the composite scaffolds were investigated by FTIR, CHNS, SEM/EDS and compression tests. The electrostatic attraction and hydrogen bonding between chitosan, alginate and halloysite was confirmed by FTIR spectroscopy. Chitosan/alginate/halloysite scaffolds exhibit significant enhancement in compressive strength compared with chitosan/alginate scaffolds. CHNS and EDS perfectly illustrate that amine groups were effectively introduced in the aminated scaffold. The growth and cell attachment of L929 cells as well as the cytotoxicity of the scaffolds were investigated by SEM and Alamar Blue (AB). The results indicated that the aminated chitosan/alginate/halloysite scaffold has better cell growth and cell adherence in comparison to that of chitosan/alginate/halloysite samples. Aminated chitosan/alginate/halloysite composite scaffolds exhibit great potential for applications in tissue engineering, ideally in

  5. Risques sur Internet pour les enfants et les jeunes: données récentes pour la Suisse

    OpenAIRE

    Hermida Martin; Signer Sara

    2013-01-01

    La plupart du temps on entend parler des risques d’Internet pour les enfants et les jeunes à la suite d’événements spectaculaires. L’étude «EU Kids Online: Suisse» s’est penchée sur l’expérience des risques sur Internet de jeunes âgés de neuf à seize ans pour fournir une base de données solide qui devrait alimenter et consolider les débats sur le sujet tant dans le grand public que parmi les acteurs politiques. Comme le montrent les résultats la probabilité pour les jeunes de ...

  6. Cheminformatics Modeling of Amine Solutions for Assessing their CO2 Absorption Properties.

    Science.gov (United States)

    Kuenemann, Melaine A; Fourches, Denis

    2017-07-01

    As stricter regulations on CO 2 emissions are adopted worldwide, identifying efficient chemical processes to capture and recycle CO 2 is of critical importance for industry. The most common process known as amine scrubbing suffers from the lack of available amine solutions capable of capturing CO 2 efficiently. Tertiary amines characterized by low heats of reaction are considered good candidates but their absorption properties can significantly differ from one analogue to another despite high structural similarity. Herein, after collecting and curating experimental data from the literature, we have built a modeling set of 41 amine structures with their absorption properties. Then we analyzed their chemical composition using molecular descriptors and non-supervised clustering. Furthermore, we developed a series of quantitative structure-property relationships (QSPR) to assess amines' CO 2 absorption properties from their structural characteristics. These models afforded reasonable prediction performances (e. g., Q 2 LOO =0.63 for CO 2 absorption amount) even though they are solely based on 2D chemical descriptors and individual machine learning techniques (random forest and neural network). Overall, we believe the chemical analysis and the series of QSPR models presented in this proof-of-concept study represent new knowledge and innovative tools that could be very useful for screening and prioritizing hypothetical amines to be synthesized and tested experimentally for their CO 2 absorption properties. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Managing Your Wine Fermentation to Reduce the Risk of Biogenic Amine Formation

    Science.gov (United States)

    Smit, Anita Yolandi; Engelbrecht, Lynn; du Toit, Maret

    2012-01-01

    Biogenic amines are nitrogenous organic compounds produced in wine from amino acid precursors mainly by microbial decarboxylation. The concentration of biogenic amines that can potentially be produced is dependent on the amount of amino acid precursors in the medium, the presence of decarboxylase positive microorganisms and conditions that enable microbial or biochemical activity such as the addition of nutrients to support the inoculated starter cultures for alcoholic and malolactic fermentation (MLF). MLF can be conducted using co-inoculation or an inoculation after the completion of alcoholic fermentation that may also affect the level of biogenic amines in wine. This study focused on the impact of the addition of complex commercial yeast and bacterial nutrients and the use of different MLF inoculation scenarios on the production of biogenic amines in wine. Results showed that the addition of complex nutrients to real grape must could potentially increase histamine concentrations in wine. The same experiment in synthetic grape must showed a similar trend for putrescine and cadaverine. The effect of different MLF inoculation scenarios was examined in two cultivars, Pinotage and Shiraz. Conflicting results was obtained. In the Shiraz, co-inoculation resulted in lower biogenic amine concentrations after MLF compared to before MLF, while the concentration was higher in the Pinotage. However, the production of biogenic amines was affected more by the presence of decarboxylase positive lactic acid bacteria than by the addition of complex nutrients or the inoculation scenario. PMID:22419915

  8. Biogenic amines in the meat of hunted pheasant and hare during the course of storage

    Directory of Open Access Journals (Sweden)

    Zdeňka Hutařová

    2014-01-01

    Full Text Available Venison is becoming more and more interesting for consumers. Although treatment procedures of hunted game differ from slaughtered livestock, the hygienic quality of game meat must still be ensured. Potential indicators of meat hygienic quality include the content of biogenic amines. The aim of the present study was to assess the content and changes of biogenic amines in the muscles of selected kinds of small game (common pheasant and brown hare during storage, and based on the obtained results, to assess the hygienic quality of the meat. Biogenic amines (putrescine, cadaverine, histamine, tyramine, phenylethylamine, and tryptamine in the breast and thigh muscles separated by reverse phase liquid chromatography and consequently were detected using tandem mass spectrometry. Based on the determined content of biogenic amines, both pheasant and hare meats complied with values of high quality meat. The sum of biogenic amines did not exceed the value of 5 mg/kg after 7 days at 0 °C or 7 °C in pheasant meat, and after 21 days at 0 °C or after 14 days at 7 °C in brown hare meat. The biogenic amine content and the speed of their formation in venison can be very helpful for the evaluation of both meat hygienic quality and safety of these foods during storage.

  9. Dynamics of CO 2 Adsorption on Amine Adsorbents. 2. Insights Into Adsorbent Design

    KAUST Repository

    Bollini, Praveen

    2012-11-21

    Packed bed breakthrough experiments are reported for commercial zeolite 13X and 3-aminopropyl-functionalized SBA-15 silica materials with three different amine loadings. Mass and heat transfer dynamics for all four materials are modeled successfully. Amine adsorbents with open pores are found to exhibit faster mass diffusion rates compared to zeolite 13X. When amine loading is increased by coupling aminopropyl groups, premature breakthrough combined with a long tail is observed. Contrary to conventional physisorbants, finite heat losses to the column wall do not explain the long breakthrough tail. A rate model that accounts for heterogeneity in diffusion was found to accurately capture the breakthrough shape of the high loading material. Batch uptake measurements support the hypothesis that slow diffusion through the polymer phase is what hampers adsorption kinetics in the high amine loading adsorbent. The results emphasize the importance of designing materials that are not overloaded with amine sites, as excessive amine loadings can lead to depressed adsorption kinetics and premature column breakthrough. © 2012 American Chemical Society.

  10. Biogenic-amine acetylation: an additional function of the N-acetyltransferase from Fasciola hepatica.

    Science.gov (United States)

    Aisien, S O; Walter, R D

    1993-01-01

    The previously described polyamine N-acetyltransferase from Fasciola hepatica has been observed to have an additional function, the acetylation of biogenic amines. The activities for biogenic amines, diamines and polyamines were in a constant ratio throughout the purification process. Biogenic amines found to be substrates for the enzyme included tyramine, tryptamine, beta-phenylethylamine and histamine, with Km values of 0.12 mM, 0.26 mM, 0.30 mM and 0.76 mM respectively. Octopamine, 5-hydroxytryptamine and alpha-phenylethylamine were also acceptable as substrates, though to a lesser degree. The optimum pH for biogenic-amine acetylation was 7.5, and CoA was inhibitory to the process, with a Ki of 5.5 microM. N-Acetylation appears to play a major role in the amine metabolism of this trematode. We presume that acetylation represents the process by which the parasite inactivates excess amines. PMID:8489501

  11. Managing your wine fermentation to reduce the risk of biogenic amine formation

    Directory of Open Access Journals (Sweden)

    Anita Yolandi Smit

    2012-03-01

    Full Text Available Biogenic amines are nitrogenous organic compounds produced in wine from amino acid precursors mainly by microbial decarboxylation. The concentration of biogenic amines that can potentially be produced is dependent on the amount of amino acid precursors in the medium, the presence of decarboxylase positive microorganisms and conditions that enable microbial or biochemical activity such as the addition of nutrients to support the alcoholic and malolactic fermentation (MLF inoculated starter cultures. MLF can be conducted using co-inoculation or inoculated after the completion of alcoholic fermentation (AF that may also affect the level of biogenic amine in the wine. This study focussed on the impact the addition of complex commercial yeast and bacterial nutrients and the use of different MLF inoculation scenarios could have on the production of biogenic amine in the wine. Results obtained with wine showed that in this study the amine that was influenced by nutrient addition was histamine. In the synthetic winemaking using 12 different treatments no clear tendencies were observed. It was shown that in certain conditions co-inoculation could reduce the amount of biogenic amines produced.

  12. Reducing the energy penalty costs of postcombustion CCS systems with amine-storage.

    Science.gov (United States)

    Patiño-Echeverri, Dalia; Hoppock, David C

    2012-01-17

    Carbon capture and storage (CCS) can significantly reduce the amount of CO(2) emitted from coal-fired power plants but its operation significantly reduces the plant's net electrical output and decreases profits, especially during times of high electricity prices. An amine-based CCS system can be modified adding amine-storage to allow postponing 92% of all its energy consumption to times of lower electricity prices, and in this way has the potential to effectively reduce the cost of CO(2) capture by reducing the costs of the forgone electricity sales. However adding amine-storage to a CCS system implies a significant capital cost that will be outweighed by the price-arbitrage revenue only if the difference between low and high electricity prices is substantial. In this paper we find a threshold for the variability in electricity prices that make the benefits from electricity price arbitrage outweigh the capital costs of amine-storage. We then look at wholesale electricity markets in the Eastern Interconnect of the United States to determine profitability of amine-storage systems in this region. Using hourly electricity price data from years 2007 and 2008 we find that amine storage may be cost-effective in areas with high price variability.

  13. Reductive amination of ketones catalyzed by whole cell biocatalysts containing imine reductases (IREDs).

    Science.gov (United States)

    Maugeri, Zaira; Rother, Dörte

    2017-09-20

    The asymmetric reductive amination of ketones represents an elegant and convenient way to obtain chiral amines. Recently, several examples have been reported in which isolated imine reductases (IREDs) have been used for this type of reaction leading to promising results. In this work we focus on the applicability of whole cell biocatalysts (recombinant E. coli cells heterologously overexpressing an IRED) to simplify its preparation and to cut on catalyst production costs. Thirteen IREDs were screened towards six different ketones, using methylamine as amine donor. The targeted amines were formed with low to very high conversions and good to excellent stereoselectivity, depending on both, the ketone amine pair used for the reaction, as well as the applied IRED. It was further proven that a micro-aqueous reaction environment was applicable showing similar activity trends for the various reductive aminations but predominantly reduced conversions. A preparative scale experiment in a buffered environment was conducted leading to 93% conversion and 99% stereoselectivity of the product (1S,3R)-N,3-dimethylcyclohexylamine. As the whole cells intrinsic glucose dehydrogenase could be used for cofactor regeneration, no enzyme addition had to be applied, making this biocatalyst formulation particularly cost efficient. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Depletion of florfenicol and florfenicol amine residues in chicken eggs.

    Science.gov (United States)

    Filazi, A; Sireli, U T; Yurdakok, B; Aydin, F G; Kucukosmanoglu, A G

    2014-01-01

    1. The aim of this study was to develop a suitable method for the analysis of florfenicol (FF) and its metabolite florfenicol amine (FFA) in chicken eggs and to determine FF and FFA residue depletion in eggs of laying hens. 2. The analytes were extracted from yolk, albumen and whole egg by phosphate buffer and ethyl acetate. Following purification, samples were analysed by high-performance liquid chromatography. 3. Fifty laying hens were divided into 5 groups, and each hen received doses of 20 mg/kg FF: Group 1 (received a single oral dose by gavage); Group 2 (a single intramuscular dose); Group 3 (a single subcutaneous dose); Group 4 (multiple oral doses for 3 d) and Group 5 (multiple oral doses for 5 d). 4. Limits of detection and of quantitation values were 1.94 and 6.45 g/10(9) g (ppb) for FF, respectively, and 0.48 and 1.58 ppb for FFA, respectively. Relative standard deviation values of intra-day and inter-day variation below 11% also confirmed the usefulness of the method for analysing FF and FFA in eggs. 5. From the first day of both oral and parenteral administration, FF and FFA were detected at 0.1% and 0.08% of dosage, respectively, and 57% of the drugs were eliminated from the egg yolk. Elimination time of FF was 8 d in Groups 1, 2 and 3; 9 d in Group 4 and 10 d in Group 5.

  15. Biogenic amines and hygienic quality of lucerne silage

    Directory of Open Access Journals (Sweden)

    Mlejnkova Veronika

    2016-01-01

    Full Text Available This experiment examined the influence of two different silage additives of biological (Lactococcus lactis, Lactobacillus plantarum, Enterococcus faecium, enzyme xylanase and chemical (43% formic acid, 30% ammonium formate, 10% propionic acid, 2% benzoic acid types on biogenic amines concentration, nutrient content, fermentation process, and microbiologic indicators in lucerne (Medicago sativa silage after 90 days of fermentation. The biological additive significantly (P < 0.05 increased putrescine (+51%, lactic acid (+11% and protein content (+11% in comparison with control silage. It significantly decreased cadaverine (−29%, histamine (−57%, spermidine (−15%, spermine (−55%, acetic acid (−40%, ethanol (−55%, ammonium (−25% and ash (−9%. After the chemical-additive treatment, greater amounts of histamine and tyramine were recorded. Significant decrease was observed in the concentrations of putrescine (−18%, cadaverine (−55%, spermidine (−47%, spermine (−45%, lactic acid (−16%, acetic acid (−46%, ammonium (−59%, ash (−13% and fat (−24%. Populations of bacteria associated with lactic acid fermentation, moulds, yeasts, enterobacteria and total microorganisms count were also influenced. Both biological and chemical additives can be highly recommended for producing high-quality silages meeting hygienic requirements. In lucerne silage, the chemical preservative showed a stronger effect in achieving the health safety of silage compared to the biological inoculant.

  16. Synthesis, Characterization, and Pharmacological Evaluation of Selected Aromatic Amines

    Directory of Open Access Journals (Sweden)

    Hammad Ismail

    2015-01-01

    Full Text Available Aromatic amines 1-amino-4-phenoxybenzene (A-1A, 2-(4-aminophenoxy naphthalene (A-2A, and 1-(4-aminophenoxy naphthalene (A-3A were synthesized by the reduction of corresponding nitroaromatics with hydrazine monohydrate and Pd/C 5% (w/w. The newly synthesized compounds were characterized by FTIR, 1H NMR, 13C NMR, UV-visible spectrophotometer, and mass spectrometry and their biological activities were investigated along with structurally similar 4-(4-aminophenyloxy biphenyl (A-A. Results of brine shrimp cytotoxicity assay showed that almost all of the compounds had LD50 values <1 μg/mL. The compounds also showed significant antitumor activity with IC50 values ranging from 67.45 to 12.2 µgmL−1. The cytotoxicity and antitumor studies correlate the results which suggests the anticancerous nature of compounds. During the interaction study of these compounds with DNA, all of the compounds showed hyperchromic effect indicating strong interaction through binding with the grooves of DNA. Moreover, A-3A also showed decrease in λmax confirming higher propensity for DNA groove binding. In DPPH free radical scavenging assay, all the compounds showed potential antioxidant capability. The compounds were highly active in protecting DNA against hydroxyl free radicals. DNA interaction and antioxidant results back up each other indicating that these compounds have potential to be used as cancer chemopreventive agents. Additionally, one compound (A-1A showed significant antibacterial and antifungal activity as well.

  17. Membrane Separation of 2-Ethyl Hexyl Amine/1-Decene

    KAUST Repository

    Bawareth, Bander

    2012-12-01

    1-Decene is a valuable product in linear alpha olefins plants that is contaminated with 2-EHA (2-ethyl hexyl amine). Using organic solvent nanofiltration membranes for this separation is quite challengeable. A membrane has to be a chemically stable in this environment with reasonable and stable separation factor. This paper shows that Teflon AF 2400 and cellulose acetate produced interesting results in 1-decene/2-EHA separation. The separation factor of Teflon AF 2400 is 3 with a stable permeance of 1.1x10-2 L/(m2·h·bar). Likewise, cellulose acetate gave 2-EHA/1-decene separation factor of 2 with a lower permeance of 3.67x10-3 L/(m2·h·bar). A series of hydrophilic membranes were tested but they did not give any separation due to high degree of swelling of 2-EHA with these polymers. The large swelling causes the membrane to lose its diffusivity selectivity because of an increase in the polymer\\'s chain mobility.

  18. Electrochemical characterization of platinum nanoparticles stabilized by amines

    International Nuclear Information System (INIS)

    Ramirez-Meneses, E.; Dominguez-Crespo, M.A.; Montiel-Palma, V.; Chavez-Herrera, V.H.; Gomez, E.; Hernandez-Tapia, G.

    2009-01-01

    In this work we present the synthesis by Chaudret approach of Pt nanoparticles stabilized by primary amine (-NH 2 ) compounds. Their electrochemical performance as cathodes in low temperature polymer electrolite fuel cells on the oxygen reduction reaction (ORR) is also presented. Transmission electron microscopy (TEM) images of the samples show Pt nanostructures with particle size varying from 10 to 100 nm depending on the kind of the stabilizer used during the catalyst preparation. In some cases well-dispersed isolated platinum nanoparticles were observed. The activity of the dispersed catalysts (Pt/C) with respect to the ORR was investigated using steady state polarization measurements. The kinetic parameters showed that although no significant differences between the Tafel slopes of the Pt catalysts exist, transfer coefficients and exchange current densities show higher activities when the Pt nanoparticles were stabilized by tert-butylamine (TBA). The performance with respect to the ORR of the Pt/C catalyst on vulcan carbon substrate is active and comparable to that reported in the literature for state-of-art electrocatalysts.

  19. Utilisation de l'essai comete et du biomarqueur gamma-H2AX pour detecter les dommages induits a l'ADN cellulaire par le 5-bromodeoxyuridine post-irradiation

    Science.gov (United States)

    La Madeleine, Carole

    Ce memoire est presente a la Faculte de medecine et des sciences de la sante de l'Universite de Sherbrooke en vue de l'obtention du grade de maitre es sciences (M.Sc.) en radiobiologie (2009). Un jury a revise les informations contenues dans ce memoire. Il etait compose de professeurs de la Faculte de medecine et des sciences de la sante soit : Darel Hunting PhD, directeur de recherche (departement de medecine nucleaire et radiobiologie), Leon Sanche PhD, directeur de recherche (departement de medecine nucleaire et radiobiologie), Richard Wagner PhD, membre du programme (departement de medecine nucleaire et radiobiologie) et Guylain Boissonneault PhD, membre exterieur au programme (departement de biochimie). Le 5-bromodeoxyuridine (BrdU), un analogue halogene de la thymidine reconnu depuis les annees 60 comme etant un excellent radiosensibilisateur. L'hypothese la plus repandue au sujet de l'effet radio sensibilisant du BrdU est qu'il augmente le nombre de cassures simple et double brin lorsqu'il est incorpore dans l'ADN de la cellule et expose aux radiations ionisantes. Toutefois, de nouvelles recherches semblent remettre en question les observations precedentes. Ces dernieres etudes ont confirme que le BrdU est un bon radiosensibilisateur, car il augmente les dommages radio-induits dans l'ADN. Mais, c'est en etant incorpore dans une region simple brin que le BrdU radiosensibilise l'ADN. Ces recherches ont egalement revele pour la premiere fois un nouveau type de dommages produits lors de l'irradiation de l'ADN contenant du BrdU : les dimeres interbrins. Le but de ces travaux de recherche est de determiner si la presence de bromodeoxyuridine dans l'ADN augmente l'induction de bris simple et / ou double brin chez les cellules irradiees en utilisant de nouvelles techniques plus sensibles et specifiques que celles utilisees auparavant. Pour ce faire, les essais cometes et la detection des foci H2AX phosphorylee pourraient permettre d'etablir les effets engendres par

  20. Publications | Page 46 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La modélisation mathématique éclaire les politiques de prévention du VIH en Chine. Un projet de recherche financé par le CRDI utilise la modélisation mathématique pour influer sur les politiques locales et nationales de réduction de la transmission du VIH en Chine.

  1. Tanzanie | Page 22 | CRDI - Centre de recherches pour le ...

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    Read more about Lutte intégrée contre les maladies humaines et animales pour les bergers contraints à la sédentarisation en Tanzanie. Langue French. Read more about Integrated Human and Animal Disease Control for Tanzanian Pastoralists Facing Settlement. Langue English. Read more about Stratégie sanitaire ...

  2. Kenya | Page 31 | CRDI - Centre de recherches pour le ...

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    Accueil · Sud du Sahara. Kenya. Kenya. Read more about Visiting Fellowship on Governance and Corruption. Langue English. Read more about Lutte intégrée contre les maladies humaines et animales pour les bergers contraints à la sédentarisation en Tanzanie. Langue French. Read more about Integrated Human and ...

  3. Projet pilote pour le programme national de recherche et de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    L'idée d'un programme national de recherche et de formation (PRIDE en espagnol) est issue du projet Mise en place de systèmes d'apprentissage au Honduras (projet 100133), soutenu par le CRDI. La subvention est accordée pour appuyer une version pilote de PRIDE, reposant sur deux appels à propositions.

  4. Publications | Page 55 | CRDI - Centre de recherches pour le ...

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    élaboration de sa prochaine stratégie quinquennale, le CRDI a organisé. ... Au cours de la dernière décennie, un certain nombre d'initiatives au Canada ont permis de mettre au point des stratégies et des forums pour permettre la mise en commun ...

  5. Inde | Page 60 | CRDI - Centre de recherches pour le ...

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    A study on mobile phone use by the poor has resulted in the cancellation of a plan to tax mobile usage in Bangladesh. Surveys on mobile expenditures in several ... for many low-income households in India. To kill the germs, people pour water into clear plastic bottles and then leave them out in the sun for several hours.

  6. Livres | Page 31 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Asie et du Sud-Est,auraient pu, en principe, partir de la Chine pour se rendre à Singapouren se balançant d'arbre. Maison(s) d'édition : CRDI. ISBN: Épuisé. Couverture du livre Community Assessment of Natural Food Sources of Vitamin A ...

  7. Assessment of the efficacy of Deltamethrin 1% pours- on (Smash ...

    African Journals Online (AJOL)

    Ethiop. Vet. J., 2014, 18 (1), 17-27. Assessment of the efficacy of Deltamethrin 1% pours- on (Smash) and Deltamethrin 1% SC (Pali) and com- parison of their mode of applications against ticks in. Ethiopia. Sileshi Mekonnen. Current address: Sileshi.Mekonnen@fao.org; FAO Ethiopia, P.O.Box 5536, Addis Ababa, Ethiopia.

  8. Recherche | Page 5 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    , vous apprendrez les techniques fondamentales de rédaction efficace, à rédiger pour des publications . ... Le tabagisme se répand rapidement en Afrique subsaharienne sous l'impulsion d'une forte croissance économique et des tactiques .

  9. Tanzanie | Page 44 | CRDI - Centre de recherches pour le ...

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    Read more about Decades of cassava research bear fruit. Langue English. Adressez-vous à un économiste en Afrique, et il est fort probable qu'il ait profité du programme de formation du Consortium pour la recherche économique en Afrique ( AERC ). Read more about Des économistes africains favorisent la croissance et ...

  10. Vaincre le vampire violet | CRDI - Centre de recherches pour le ...

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    Est depuis le début des années 1990 lorsque le Centre de recherches pour le développement international, une société d'État canadienne, l'a invité à se pencher sur le problème de la striga en Afrique subsaharienne.

  11. Investir dans les conseils scientifiques pour les gouvernements afin ...

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    10 oct. 2017 ... S'attaquer à la marginalisation, à la criminalité et à la violence chez les jeunes - le rôle du capital social communautaire. Il est maintenant reconnu que les adolescents ont besoin d'un capital social positif (réseaux sociaux, relations interpersonnelles) pour devenir des adultes productifs et socialement.

  12. Publications | Page 163 | CRDI - Centre de recherches pour le ...

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    An Introduction to the Human Development and Capability Approach : Freedom and Agency. Depuis 1990, le Programme des Nations Unies pour le développement ... Gender and Natural Resource Management : Livelihoods, Mobility and Interventions. Depuis dix ans aucun ouvrage n'a jeté un regard synoptique sur l'axe ...

  13. Kenya | Page 29 | CRDI - Centre de recherches pour le ...

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    Read more about East African GEOHealth hub for preventing environmental and occupational health risks. Langue English. Read more about Accroître les possibilités économiques pour les jeunes dans les secteurs du poisson et de la volaille au Kenya (CultivAf). Langue French. Read more about The Alliance to Scale ...

  14. Publications | Page 40 | CRDI - Centre de recherches pour le ...

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    Amérique du Nord et de l'Europe pour inclure maintenant un plus grand nombre d'établissements de recherche africains. Activité antérieure : Le CRDI au Congrès mondial sur la santé publique 2015. Le 14e Congrès mondial sur la santé publique ...

  15. Publications | Page 181 | CRDI - Centre de recherches pour le ...

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    Economic Liberalization and Political Violence : Utopia or Dystopia ? Un ouvrage essentiel pour quiconque souhaite comprendre les conflits et le développement au XXIe siècle. James Putzel, Crisis States Research Centre, London School of Economics. Alors que certains voient en la mondialisation un outil de ...

  16. Publications | Page 186 | CRDI - Centre de recherches pour le ...

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    Economic Liberalization and Political Violence : Utopia or Dystopia ? Un ouvrage essentiel pour quiconque souhaite comprendre les conflits et le développement au XXIe siècle. James Putzel, Crisis States Research Centre, London School of Economics. Alors que certains voient en la mondialisation un outil de ...

  17. Apprentissage en collaboration pour la cogestion des ressources ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Apprentissage en collaboration pour la cogestion des ressources naturelles en Mongolie. Les prairies et les steppes de la Mongolie abritent actuellement quelque 35 millions de têtes de bétail et 180 ... Outputs. Reports. Collaborative learning for the co-management of natural resources in Mongolia : final technical report ...

  18. Agriculture et environnement | CRDI - Centre de recherches pour le ...

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    appui au développement de la culture du poivre et de la vanille pourrait ... Pour dissuader les gouvernements de ces pays de mettre en oeuvre des politiques visant à réduire la consommation de tabac (telles que la hausse des taxes, ...

  19. Publications | Page 135 | CRDI - Centre de recherches pour le ...

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    outils pour le suivi et l'évaluation des initiatives d'adaptation aux effets du changement climatique : étude de cas PADESO; rapport final (restricted access) · Impact de la décharge de Mbeubeuss sur les ressources en eau et sur les sols ...

  20. Publications | Page 27 | CRDI - Centre de recherches pour le ...

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    Avec nos livres, nos articles, nos publications de recherche et nos études, nous visons à accroître l'impact de nos investissements et à promouvoir la recherche au service du développement. Nous communiquons les ... Transformer les pratiques d'irrigation pour lutter contre la malaria dans le nord du Pérou. Comprendre et ...

  1. De nouveaux vaccins pour animaux pourraient aider davantage d ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    9 juil. 2013 ... Marie-Danielle Smith. Des scientifiques canadiens et africains mettent au point de nouveaux vaccins pour lutter contre les maladies animales et limiter les pertes économiques en Afrique subsaharienne. Certains de ces vaccins pourraient permettre de lutter contre des maladies semblables au Canada.

  2. Droits d'auteur | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Droits d'auteur détenus par le CRDI Sauf indication contraire, les droits d'auteur relatifs aux documents mis en ligne sur le présent site Web sont détenus par le Centre de recherches pour le développement international (CRDI).

  3. À propos du CRDI | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le Centre de recherches pour le développement international (CRDI) finance des travaux de recherche dans les pays en développement afin d'y favoriser la croissance, de réduire la pauvreté et d'impulser des changements positifs à grande échelle.

  4. Publications | Page 102 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La fonte des glaciers en Bolivie est un signe de changement climatique. Scientifiques et agriculteurs combinent des techniques agricoles traditionnelles et la recherche de pointe pour cultiver la terre de façon durable dans les Hautes Andes, où l'équilibre écologique change rapidement.

  5. Publications | Page 106 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    1 Intégration des données météorologiques et du savoir autochtone aux prévisions climatiques saisonnières pour le secteur agricole. Sous la direction de Gina Ziervogel et Alfred Opere, en collaboration avec : Ignitius Chagonda ; Jacob Churi ; Amadou Dieye ; Boris Houenou ; Said Hounkponou ; Eric Kisiangani ; Evans ...

  6. De nouveaux vaccins pour animaux pourraient aider davantage d ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    9 juil. 2013 ... Des scientifiques canadiens et africains mettent au point de nouveaux vaccins pour lutter contre les maladies animales et limiter les pertes économiques en Afrique subsaharienne. Certains de ces vaccins pourraient permettre de lutter contre des maladies semblables au Canada.

  7. The World Bank | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Accueil · Ce que nous faisons · Nos partenaires et initiatives. The World Bank. The World Bank. http://www.worldbank.org/ · Ce que nous faisons · Financement · Ressources · À propos du CRDI. Savoir. Innovation. Solutions. Carrières · Communiquez avec nous · Plan du site. Abonnez-vous à notre bulletin pour recevoir les ...

  8. Uganda : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le présent projet porte sur la création d'emplois pour les jeunes et les femmes en Afrique, en mettant l'accent sur les petites et moyennes entreprises (PME) du secteur du tourisme. Sujet: Gender. Région: Mauritius, Tanzania, Uganda. Programme: Emploi et croissance. Financement total : CA$ 646,600.00. Pourquoi ne se ...

  9. Livres | Page 30 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Asie et du Sud-Est,auraient pu, en principe, partir de la Chine pour se rendre à Singapouren se balançant d'arbre. Maison(s) d'édition : CRDI. ISBN: Épuisé. Couverture du livre Community Assessment of Natural Food Sources of Vitamin A ...

  10. Contrat et confiance pour la gestion des risques de defaillances ...

    African Journals Online (AJOL)

    Penser et mettre en oeuvre de nouveaux mécanismes de gestion des risques de défaillance dans les transactions de financement agricole, qui soient plus efficaces et moins contraignants pour les agriculteurs, constituent l'un des défis majeurs du développement des systèmes financiers ruraux dans les pays en ...

  11. Les femmes se tournent vers les arbres fourragers pour engraisser ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    12 févr. 2018 ... Avec l'appui de la recherche, les femmes d'une commune rurale du Mali savent maintenant comment utiliser les arbres fourragers pour nourrir leurs moutons. Lorsqu'elles ont remplacé le régime alimentaire de leurs moutons, ceux dont la ration incorporait des feuilles de ligneux fourragers ont gagné ...

  12. De nouveaux partenariats pour stimuler l'innovation en agriculture ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Bien que la hausse en flèche du prix des aliments connaisse une certaine accalmie, il en coûte beaucoup plus cher qu'il y a quelques années à bon nombre de consommateurs pauvres des pays en développement pour se nourrir.

  13. Publications | Page 33 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le Centre de recherches pour le développement international (CRDI) appuie le projet Research into Open Educational Resources for Development ou ROER4D (Recherche sur les ressources éducatives libres au service du développement), dont l'objectif est d'améliorer les politiques, les pratiques et la recherche en ...

  14. Publications | Page 34 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le Centre de recherches pour le développement international (CRDI) appuie le projet Research into Open Educational Resources for Development ou ROER4D (Recherche sur les ressources éducatives libres au service du développement), dont l'objectif est d'améliorer les politiques, les pratiques et la recherche en ...

  15. Publications | Page 103 | CRDI - Centre de recherches pour le ...

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    Le FIE 2008 fait avancer le cadre écobiosocial de l'OMS. Le Programme spécial de recherche et de formation concernant les maladies tropicales (TDR) de l'OMS a élaboré le concept du champ « écobiosocial », qui combine les perspectives écologiques, biologiques et sociales « pour mieux.

  16. Recherche | Page 5 | CRDI - Centre de recherches pour le ...

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    2004-04-22

    Africa is highly vulnerable to climate change, and finding ways to adapt is imperative ... He guides and monitors projects mainly dealing with sea level rise, water ... IDRC's fight against malaria | CRDI - Centre de recherches pour le ... Apr 22, 2004 ... 2004-04-22BACKGROUNDERIn Africa, malaria kills an African child .

  17. Inde | Page 80 | CRDI - Centre de recherches pour le ...

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    Learning Initiatives on Reforms for Network Economies) is exploring, among other topics, ... Langue English. Il y a huit ans, Loyola Joseph, de la Foundation of Occupational Development (FOOD India), a commencé à se demander comment faire pour ...

  18. Publications | Page 79 | CRDI - Centre de recherches pour le ...

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    Le Sri Lanka mieux préparé aux futurs tsunamis. Les collectivités côtières vulnérables du Sri Lanka sont désormais mieux outillées pour survivre aux tsunamis, cyclones et autres catastrophes naturelles survenant soudainement. Ce degré accru de.

  19. Journal des Sciences Pour l'Ingénieur

    African Journals Online (AJOL)

    Bien au-delà des disciplines Sciences pour l'Ingénieur (Mécanique, Electrique, Civil, Informatique, Chimique…), le journal est ouvert plus largement aux Sciences, de manière à faire écho aux caractères souvent interdisciplinaires des recherches actuelles. Other sites related to this journal: http://www.jspi.sn/ ...

  20. Des outils novateurs pour lutter contre les maladies chroniques au ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    UNWRA). Les populations rurales du Liban ont, quant à elles, accès au système de santé national, mais n'ont souvent pas accès aux moyens de transport ou autres moyens nécessaires pour se rendre aux points de service.

  1. Tendances mondiales et meilleures pratiques pour soutenir les ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Tendances mondiales et meilleures pratiques pour soutenir les entrepreneurs : points saillants de la table ronde internationale des économistes en chef. 30 novembre 2017. Image. BDC. Les petites et moyennes entreprises (PME) sont essentielles à la croissance économique et à l'emploi dans le monde entier, mais elles ...

  2. Publications | Page 75 | CRDI - Centre de recherches pour le ...

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    Étude de l'accessibilité à l'eau potable dans les villages pilotes du projet irrigation de complément et information climatique dans la commune de Kongoussi (restricted access). Le gouvernement burkinabé et ses partenaires ont consenti beaucoup d''efforts en construisant des points d''eau modernes pour atteindre les OMD ...

  3. Appel à propositions pour le concours de 2018 du Programme ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    23 nov. 2017 ... Ces plans peuvent proposer tout un éventail d'activités appuyant les objectifs de recherche et de formation de la proposition et tirer profit de cette occasion de financement pour concevoir un projet de recherche collaboratif international. Le processus de demande de cette occasion de financement ...

  4. Consensus formalisé: recommandations de pratiques cliniques pour ...

    African Journals Online (AJOL)

    Destiné aux praticiens, ce travail collaboratif multinational a pour objectif de fournir 16 recommandations de pratiques cliniques simples, fondées sur les preuves, et adaptées aux conditions de l'exercice médical en Afrique. The Pan African Medical Journal 2016;24. AJOL African Journals Online. HOW TO USE AJOL.

  5. Entretien avec Susan Holtz | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    26 nov. 2010 ... La production de rapports publics est importante, car pour produire des rapports qui veulent vraiment dire quelque chose, il faut préciser clairement les ... politiques et écologiques idéalistes avec ce que les êtres humains semblent vouloir en réalité comme croissance économique, automobiles et biens ...

  6. uganda : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le présent projet porte sur la création d'emplois pour les jeunes et les femmes en Afrique, en mettant l'accent sur les petites et moyennes entreprises (PME) du secteur du tourisme. Région: Mauritius, Tanzania, Uganda. Programme: Employment and Growth. Financement total : CA$ 646,600.00. Pourquoi ne se battent-ils ...

  7. Publications | Page 2 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Tendances mondiales et meilleures pratiques pour soutenir les entrepreneurs : points saillants de la table ronde internationale des économistes en chef. Les petites et moyennes entreprises (PME) sont essentielles à la croissance économique et à l'emploi dans le monde entier, mais elles ont une incidence encore plus ...

  8. Publications | Page 74 | CRDI - Centre de recherches pour le ...

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    environnement en Angola, un bénéficiaire de subvention de longue date du CRDI conjugue des observations obtenues par satellite et des données... Petits bassins individuels pour l'irrigation de complément : analyse diagnostique des bassins ...

  9. Publications | Page 50 | CRDI - Centre de recherches pour le ...

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    ... développement persistants auxquels elle est confrontée, l'Afrique abrite certaines des économies qui connaissent la croissance la plus rapide au monde. L'entrepreneuriat y... Favoriser l'entrepreneuriat. Pour comprendre les entrepreneurs d'aujourd'hui, il suffit de s'en remettre au Global Entrepreneurship Monitor (GEM).

  10. Publications | Page 65 | CRDI - Centre de recherches pour le ...

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    Quels sont les liens entre l'eau et l'énergie au regard des changements climatiques ? Des technologies d'énergies renouvelables décentralisées pour les services d'approvisionnement en eau pourraient‑elles aider les collectivités pauvres des pays en développement à s'adapter plus efficacement aux changements.

  11. Publications | Page 73 | CRDI - Centre de recherches pour le ...

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    Quels sont les liens entre l'eau et l'énergie au regard des changements climatiques ? Des technologies d'énergies renouvelables décentralisées pour les services d'approvisionnement en eau pourraient‑elles aider les collectivités pauvres des pays en développement à s'adapter plus efficacement aux changements.

  12. Inde | Page 90 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    However, as entrepreneurs scour the world in search of new commodities, a voice of dissent is growing and striving to be heard. ... entreprises doivent se faire concurrence pour survivre, prendre de l'expansion et occuper une part du marché, les bibliothécaires et les professionnels de l'information doivent jouer un rôle plus ...

  13. Des statistiques essentielles | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    un programme de recherche sur le terrain mené pour le compte du Centre international de recherche sur les maladies diarrhéiques. Au début, les accoucheuses traditionnelles faisaient état de variations démographiques hebdomadaires dans ...

  14. Guatemala : tous les projets | CRDI - Centre de recherches pour le ...

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    'allier pour éradiquer la maladie de Chagas en Amérique centrale. Projet. Les pertes économiques mondiales causées par la maladie de Chagas sont estimées à 7 milliards d'USD par an. Région: Guatemala. Programme: Food, Environment ...

  15. Initiative Think tank | CRDI - Centre de recherches pour le ...

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    L'ITT est le fruit d'un partenariat regroupant cinq bailleurs de fonds. Lancée en 2008, l'ITT est administrée par le Centre de Recherches pour le Développement International (CRDI), un organisme canadien.

  16. Ce que nous faisons | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le CRDI appuie des travaux de recherche dans les pays en voie de développement en vue de produire un changement réel et durable. Ce savoir peut servir d'outil pour résoudre des problèmes mondiaux urgents. Nous partageons ce savoir avec les autres en :

  17. Inde | Page 89 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    , mettant en péril la vie humaine et les écosystèmes. De plus, ils sont souvent sources de conflit entre populations et industrie. En adoptant une approche écosystémique globale pour examiner les intérêts divergents et leurs conséquences, ...

  18. Eau, terre et vie : Communication participative pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    6 févr. 2007 ... Eau, terre et vie : Communication participative pour le développement et gestion des ressources naturelles ... Le CRDI investit dans des solutions locales aux problèmes auxquels l'Inde est confrontée, comme le stress thermique, la gestion de l'eau et les migrations liées aux changements climatiques.

  19. Recherche | Page 5 | CRDI - Centre de recherches pour le ...

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    Gestion des risques climatiques pour la planification de l'agriculture ... La province du Cap-Occidental est le secteur le plus rentable sur le plan de l' agriculture en Afrique du Sud et contribue de manière importante à la balance des .

  20. Publications | Page 29 | CRDI - Centre de recherches pour le ...

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    Coutumes et croyances favorables et defavorables pour une gestion inclusive de la securite (open access). L''étude objective des sources et des données ethnographiques montre que la culture dominante dans la zone Ouest africaine, se définit en termes de dialogue, de compromis, de coexistence et de paix. Dans cette ...

  1. Publications | Page 172 | CRDI - Centre de recherches pour le ...

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    E-Commerce in the Asian Context : Selected Case Studies. Le commerce électronique en Asie retient beaucoup l'attention en raison de la prolifération des connexions Internet et des technologies connexes dans la région. Face à cette tendance, le Centre de recherches pour le développement international (.

  2. Publications | Page 173 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    E-Commerce in the Asian Context : Selected Case Studies. Le commerce électronique en Asie retient beaucoup l'attention en raison de la prolifération des connexions Internet et des technologies connexes dans la région. Face à cette tendance, le Centre de recherches pour le développement international (.

  3. Publications | Page 156 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Evictions and the Right to Housing : Experience from Canada, Chile, the Dominican Republic, South Africa, and South Korea. Le droit au logement est un droit fondamental de la personne réaffirmé en juin 1996 lorsque les gouvernements du monde entier se sont réunis à Istanbul, en Turquie pour Habitat II – la deuxième ...

  4. Pouring and running a protein gel by reusing commercial cassettes.

    Science.gov (United States)

    Hwang, Alexander C; Grey, Paris H; Cuddy, Katrina; Oppenheimer, David G

    2012-02-12

    The evaluation of proteins using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis is a common technique used by biochemistry and molecular biology researchers. For laboratories that perform daily analyses of proteins, the cost of commercially available polyacrylamide gels (~$10/gel) can be considerable over time. To mitigate this cost, some researchers prepare their own polyacrylamide gels. Traditional methods of pouring these gels typically utilize specialized equipment and glass gel plates that can be expensive and preclude pouring many gels and storing them for future use. Furthermore, handling of glass plates during cleaning or gel pouring can result in accidental breakage creating a safety hazard, which may preclude their use in undergraduate laboratory classes. Our protocol demonstrates how to pour multiple protein gels simultaneously by recycling Invitrogen Nupage Novex minigel cassettes, and inexpensive materials purchased at a home improvement store. This economical and streamlined method includes a way to store the gels at 4°C for a few weeks. By re-using the plastic gel cassettes from commercially available gels, labs that run frequent protein gels can save significant costs and help the environment. In addition, plastic gel cassettes are extremely resistant to breakage, which makes them ideal for undergraduate laboratory classrooms.

  5. Les femmes arabes toujours en lutte pour leurs droits | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    29 janv. 2013 ... Une campagne ayant mené à la reconnaissance juridique des droits en matière de nationalité des femmes arabes dans neuf pays et territoires constitue une source d'inspiration et de solutions stratégiques pour les femmes qui, un peu partout au Moyen-Orient, se heurtent à une discrimination croissante.

  6. Publications | Page 133 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le 28 juin 2006, le domaine de programme Innovation, politique et science (IPS) a présenté au Conseil des gouverneurs du CRDI un plan stratégique pour orienter la phase initiale (2006 2011) des recherches ... Simultanément, il explore certaines des options permettant d'envisager la revitalisation de ce processus.

  7. New particle formation from sulfuric acid and amines: Similarities and differences between mono-, di-, and trimethylamines

    Science.gov (United States)

    Olenius, Tinja; Halonen, Roope; Kurtén, Theo; Henschel, Henning; Kupiainen-Määttä, Oona; Ortega, Ismael K.; Vehkamäki, Hanna; Riipinen, Ilona

    2017-04-01

    Amines are organic base species that are emitted to the atmosphere from both anthropogenic and natural sources. Both theoretical and laboratory studies suggest that mono-, di-, and trimethylamines (MMA, DMA, and TMA, respectively) are capable of enhancing the initial steps of sulfuric acid-driven aerosol particle formation much more strongly than ammonia (Kurtén et al., 2008; Jen et al., 2014). Despite the potential importance for atmospheric new particle formation, quantitative estimates on the emissions and thermochemical properties of amines remain relatively uncertain. Because of this and also due to computational reasons, recent large-scale modeling studies have treated sulfuric acid-amine nucleation by introducing a single surrogate amine species, the total emissions of which combine together MMA, DMA and TMA but which resembles DMA or TMA in its various properties (e.g. Bergman et al., 2015). On the other hand, there are likely to be differences in the potentials of the three amines to enhance particle formation, causing uncertainties to the lumping approach. Systematic comparisons are needed to evaluate how to treat these species in atmospheric models and to assess what level of simplification is justifiable. In this work, we study the differences and similarities of MMA, DMA and TMA by modeling nanoparticle formation from sulfuric acid, water, and each of the three amines. We simulate molecular cluster concentrations and formation rates at boundary layer conditions with a dynamic cluster population model using quantum chemistry-based cluster evaporation rates, and study the dependence of particle formation rate on precursor vapor concentrations, temperature and relative humidity. The results suggest that for the three amines, there are differences in the nucleation mechanism and hygroscopicity of molecular clusters. However, for DMA and TMA, formation of nanometer-sized particles and its dependence on ambient conditions is roughly similar: both

  8. New CO2 adsorbent containing aminated poly(glycidyl methacrylate) grafted onto irradiated PE-PP nonwoven sheet

    International Nuclear Information System (INIS)

    Mahmoud Nasef, Mohamed; Abbasi, Ali; Ting, T.M.

    2014-01-01

    A new CO 2 adsorbent containing triethylamine (TEA) was prepared by radiation induced grafting of glycidyl methacrylate (GMA) onto polyethylene coated polypropylene (PE-PP) non-woven sheet followed by amination reaction. The degree of grafting (DOG%) was controlled by variation of monomer concentration and absorbed dose. The incorporation of aminated poly(GMA) was investigated by Fourier transform infrared (FTIR) and scanning electron microscope (SEM). The adsorbent with DOG of 350% and amination yield of 60% exhibited CO 2 adsorption capacity of 4.52 mol/kg at ambient temperature and pressure. - Highlights: • Preparation of a new aminated fibrous adsorbent for CO 2 capturing. • Grafting of GMA onto PP-PE nonwoven sheet followed by amination. • Dependence of degree of grafting on monomer concentration and absorbed dose. • FTIR and SEM evidences of grafting and amination. • CO 2 adsorbent with high adsorption capacity at ambient temperature and pressure

  9. Analysis of the DWPF glass pouring system using neural networks

    International Nuclear Information System (INIS)

    Calloway, T.B. Jr.; Jantzen, C.M.

    1997-01-01

    Neural networks were used to determine the sensitivity of 39 selected Melter/Melter Off Gas and Melter Feed System process parameters as related to the Defense Waste Processing Facility (DWPF) Melter Pour Spout Pressure during the overall analysis and resolution of the DWPF glass production and pouring issues. Two different commercial neural network software packages were used for this analysis. Models were developed and used to determine the critical parameters which accurately describe the DWPF Pour Spout Pressure. The model created using a low-end software package has a root mean square error of ± 0.35 inwc ( 2 = 0.77) with respect to the plant data used to validate and test the model. The model created using a high-end software package has a R 2 = 0.97 with respect to the plant data used to validate and test the model. The models developed for this application identified the key process parameters which contribute to the control of the DWPF Melter Pour Spout pressure during glass pouring operations. The relative contribution and ranking of the selected parameters was determined using the modeling software. Neural network computing software was determined to be a cost-effective software tool for process engineers performing troubleshooting and system performance monitoring activities. In remote high-level waste processing environments, neural network software is especially useful as a replacement for sensors which have failed and are costly to replace. The software can be used to accurately model critical remotely installed plant instrumentation. When the instrumentation fails, the software can be used to provide a soft sensor to replace the actual sensor, thereby decreasing the overall operating cost. Additionally, neural network software tools require very little training and are especially useful in mining or selecting critical variables from the vast amounts of data collected from process computers

  10. Algorithmes et architectures pour ordinateurs quantiques supraconducteurs

    Science.gov (United States)

    Blais, A.

    2003-09-01

    'utilisation de qubits basés sur les jonctions Josephson. On présente entre autres une approche originale pour l'interaction entre qubits. Cette approche est très générale puisqu'elle peut être appliquée à différents designs de qubits. Finalement, on s'intéresse à la lecture des qubits supraconducteurs de flux. Le détecteur suggéré ici a l'avantage de pouvoir être découplé du qubit lorsqu'il n'y a pas de mesure en cours.

  11. Synthesis and characterization of aminated perfluoro polymer electrolytes

    Science.gov (United States)

    Page-Belknap, Zachary Stephan Glenn

    Polymer electrolytes have been developed for use in anion exchange membrane fuel cells for years. However, due to the highly corrosive environment within these fuel cells, poor chemical stability of the polymers and low ion conductivity have led to high development costs and thus prevention from widespread commercialization. The work in this study aims to provide a solution to these problems through the synthesis and characterization of a novel polymer electrolyte. The 800 EW 3M PFSA sulfonyl fluoride precursor was aminated with 3-(dimethylamino)-1-propylamine to yield a functional polymer electrolyte following quaternization, referred to in this work as PFSa-PTMa. 1 M solutions of LiPF6, HCL, KOH, NaOH, CsOH, NaHCO3 and Na2CO3 were used to exchange the polymer to alternate counterion forms. Chemical structure analysis was performed using both FT and ATR infrared spectroscopy to confirm sulfonyl fluoride replacement and the absence of sulfonic acid sites. Mechanical testing of the polymer, following counterion exchange with KOH, at saturated conditions and 60 ºC exhibited a tensile strength of 13 +/- 2.0 MPa, a Young's modulus of 87 +/- 16 MPa and a degree of elongation reaching 75% +/- 9.1%, which indicated no mechanical degradation following exposure to a highly basic environment. Conductivities of the polymer in the Cl- and OH- counterion forms at saturated conditions and 90 ºC were observed at 26 +/- 8.0 mS cm-1 and 1.1 +/- 0.1 mS cm-1, respectively. OH- conductivities were slightly above those observed for CO32- and HCO 3- counterions at the same conditions, 0.63 +/- 0.18 and 0.66 +/- 0.21 mS cm-1 respectively. The ion exchange capacity (IEC) of the polymer in the Cl- counterion form was measured via titration at 0.57 meq g-1 which correlated to 11.2 +/- 0.10 water molecules per ion site when at 60ºC and 95% relative humidity. The IEC of the polymer in the OH- counterion form following titration expressed nearly negligible charge density, less than 0.01 meq

  12. Metal Monolithic Amine-grafted Zeolite for CO{sub 2} Capture

    Energy Technology Data Exchange (ETDEWEB)

    Chuang, Steven

    2011-03-31

    The solid amine sorbent for CO{sub 2} capture process has advantages of simplicity and low operating cost compared to the MEA (monoethanolamine) process. Solid amine sorbents reported so far suffered from either low CO{sub 2} capture capacity or low stability. The solid amine sorbent developed in this project exhibited more than 3.2 mmol/g and degraded less than 10% even after 500 cycles of heating and cooling in absence of steam. The presence of steam further enhanced CO{sub 2} capture capacity. The cost of the sorbent is estimated to be less than $7.00/lb. This sorbent was developed using the results of in situ infrared spectroscopic study. Infrared results showed that CO{sub 2} adsorbs on TEPA (tetraethylenepentamine)/PEG (polyethylene glycol) as carbamates and bicarbonates. The CO{sub 2} adsorption capacity and oxidation resistance of the amine sorbent can be enhanced by the interactions between NH{sub 2} of TEPA molecules with the OH group of PEG molecules. PEG was also found to be effectively disperse and immobilize the aromatic amines for SO{sub 2} adsorption. The infrared study also showed that SiO{sub 2} is a significantly better support than zeolites due to its proper hydrophobicity. The results of this study led to the development of a high performance solid amine sorbent under simulated gas flow condition in a fixed bed, a fluidized bed, and a metal monolith unit. This study showed heat transfer could become a major technical issue in scaling up a fixed bed adsorber. The use of the fluidized bed and metal monoliths can alleviate the heat transfer issue. The metal monolith could be suitable for small scale applications due to the high cost of manufacturing; the fluidized bed mode would be most suitable for large scale applications. Preliminary economic analysis suggested that the Akron solid amine process would cost 45% less than that of MEA process.

  13. Solid amine sorbents for CO2 capture by chemical adsorption: A review

    Directory of Open Access Journals (Sweden)

    Elif Erdal Ünveren

    2017-03-01

    Full Text Available Amines are well-known for their reversible reactions with CO2, which make them ideal for CO2 capture from several gas streams, including flue gas. In this respect, selective CO2 absorption by aqueous alkanolamines is the most mature technology but the process is energy intensive and has also corrosion problems. Both disadvantages can be diminished to a certain extent by chemical adsorption of CO2 selectively. The most important element of the chemical adsorption of CO2 involves the design and development of a suitable adsorbent which consist of a porous support onto which an amine is attached or immobilized. Such an adsorbent is often called as solid amine sorbent. This review covers solid amine-based studies which are developed and published in recent years. First, the review examines several different types of porous support materials, namely, three mesoporous silica (MCM-41, SBA-15 and KIT-6 and two polymeric supports (PMMA and PS for CO2 adsorption. Emphasis is given to the synthesis, modifications and characterizations -such as BET and PXRD data-of them. Amination of these supports to obtain a solid amine sorbent through impregnation or grafting is reviewed comparatively. Focus is given to the adsorption mechanisms, material characteristics, and synthesis methods which are discussed in detail. Significant amount of original data are also presented which makes this review unique. Finally, relevant CO2 adsorption (or equilibrium capacity data, and cyclic adsorption/desorption performance and stability of important classes of solid amine sorbents are critically reviewed. These include severa PEI or TEPA impregnated adsorbents and APTES-grafted systems.

  14. Characterization of EGF coupling to aminated silicone rubber surfaces.

    Science.gov (United States)

    Klenkler, Bettina J; Sheardown, Heather

    2006-12-20

    Tethering of growth factors to biomaterial substrates via a polyethylene glycol (PEG) spacer has been established as a means of controlling dosage and conformation of the protein at the material surface, while retaining biological activity. However, the extent of modification through a comparison of bound versus unbound protein has not generally been characterized. In this work, covalent tethering of epidermal growth factor (EGF) to allylamine plasma modified polydimethylsiloxane (PDMS) substrates is characterized to determine the nature of the bound growth factor and to optimize the conditions for the reaction. Tethering is achieved via conjugation of EGF with homobifunctional N-hydroxysuccinimide (NHS) ester of PEG-butanoic acid (SBA2-PEG) in solution, followed by exposure of the pegylated EGF to the aminated surfaces (solution first reaction). SDS-PAGE analysis indicates that a low ratio of EGF:PEG is required to maximize the yield of the EGF-PEG reaction; a relatively short reaction time is needed to limit hydrolysis of the NHS ester. With increasing amounts of PEG and a higher reaction time, a higher fraction of the EGF can be covalently tethered to the surfaces, as shown by binding of 125I-labeled EGF and subsequent washing with sodium dodecyl sulfate (SDS) to remove adsorbed protein. However, even under the optimal reaction conditions established by the SDS-PAGE analysis, higher molecular weight EGF-PEG complexes are observed by SDS-PAGE and matrix-assisted laser desorption/ionization (MALDI). The presence of these complexes, as well as unreacted growth factor, can lead to a surface of heterogeneous composition. While these surfaces were found to have biological activity, stimulating the adhesion and growth of corneal epithelial cells versus PDMS controls, further optimization of reaction conditions, including the use of a homobifunctional PEG linker and possibly separation of reaction species are required to achieve a uniformly active and well

  15. [Migration of monomers and primary aromatic amines from nylon products].

    Science.gov (United States)

    Mutsuga, Motoh; Yamaguchi, Miku; Ohno, Hiroyuki; Kawamura, Yoko

    2010-01-01

    Migration of 2 kinds of monomer and 21 kinds of primary aromatic amines (PAAs) from 21 kinds of nylon products such as turners, ladles and wrap film were determined. Samples were classified as regards materials by mean of pyrolysis-GC/MS. One sample was classified as nylon 6, 15 samples as nylon 66 and three samples as nylon 6/66 copolymers, while two samples were laminate of nylon 6 with polyethylene or polypropylene. All of the nylon 66 samples contained a small amount of ε-caprolactam (CPL), which is the nylon 6 monomer. Migration levels of monomers and PAAs at 60°C for 30 min into 20% ethanol were measured by LC/MS/MS. CPL was detected at the level of 0.015-38 µg/mL from all samples, excluding one wrap film sample, and 1,6-hexamethylenediamine was detected at the level of 0.002-0.013 µg/mL from all nylon 66 samples and one nylon 6/66 sample. In addition, 0.006-4.3 µg/mL of 4,4'-diaminodiphenylmethane from three samples, 0.032-0.23 µg/mL of aniline from four samples, 0.001 µg/mL of 4-chloroaniline from two samples, and 0.002 µg/mL of 2-toluidine and 0.066 mg/mL of 1-naphthylamine from one sample each were detected. The migration levels at 95 or 121°C were about 3 and 10 times the 60°C levels, respectively.

  16. Selection of Amine-Oxidizing Dairy Lactic Acid Bacteria and Identification of the Enzyme and Gene Involved in the Decrease of Biogenic Amines

    Science.gov (United States)

    Guarcello, Rosa; De Angelis, Maria; Settanni, Luca; Formiglio, Sabino; Gaglio, Raimondo; Moschetti, Giancarlo; Gobbetti, Marco

    2016-01-01

    ABSTRACT Accumulation of biogenic amines (BAs) in cheese and other foods is a matter of public health concern. The aim of this study was to identify the enzyme activities responsible for BA degradation in lactic acid bacteria which were previously isolated from traditional Sicilian and Apulian cheeses. The selected strains would control the concentration of BAs during cheese manufacture. First, 431 isolates not showing genes encoding the decarboxylases responsible for BA formation were selected using PCR-based methods. Ninety-four out of the 431 isolates degraded BAs (2-phenylethylamine, cadaverine, histamine, putrescine, spermine, spermidine, tyramine, or tryptamine) during cultivation on chemically defined medium. As shown by random amplification of polymorphic DNA-PCR and partial sequencing of the 16S rRNA gene, 78 of the 94 strains were Lactobacillus species (Lactobacillus casei, Lb. fermentum, Lb. parabuchneri, Lb. paracasei, Lb. paraplantarum, and Lb. rhamnosus), Leuconostoc species (Leuconostoc lactis and Ln. mesenteroides), Pediococcus pentosaceus, Lactococcus lactis, Streptococcus species (Streptococcus gallolyticus and S. thermophilus), Enterococcus lactis, and Weissella paramesenteroides. A multicopper oxidase-hydrolyzing BA was purified from the most active strain, Lb. paracasei subsp. paracasei CB9CT. The gene encoding the multicopper oxidase was sequenced and was also detected in other amine-degrading strains of Lb. fermentum, Lb. paraplantarum, and P. pentosaceus. Lb. paracasei subsp. paracasei CB9CT and another strain (CACIO6CT) of the same species that was able to degrade all the BAs were singly used as adjunct starters for decreasing the concentration of histamine and tyramine in industrial Caciocavallo cheese. The results of this study disclose a feasible strategy for increasing the safety of traditional cheeses while maintaining their typical sensorial traits. IMPORTANCE Because high concentrations of the potentially toxic biogenic amines may be

  17. Pour la viande en tranche, le mode de cuisson et l’efficacité masticatoire impactent la biodisponibilité des acides aminés

    OpenAIRE

    Bax, Marie-Laure; Brustel, P.Y.; Salel, A.; Sébédio, Jean-Louis; Hafnaoui, Noureddine; Buisson, Charline; Buffière, Caroline; Remond, Didier

    2014-01-01

    The strengths of meat protein: amino acid composition, digestibility and digestion rate. In order to improve our knowledge of the nutritional quality of meat protein, a research program (ANRPRONUTRIAL), involving both animal and human studies, was developed. Particular attention was given to meat protein digestibility in the small intestine (DIr), and to digestion rate, according to cooking parameters. It was shown that meat protein DIr is high (on average 95% in minipigs, and 92% in healthy ...

  18. Intelligent packaging : développement d'un tag pour les amines biogènes et l'éthanol

    OpenAIRE

    Jerjen, David; Wuest, Matthias

    2008-01-01

    Objectif L’objectif est de produire une couche sensitive (tag) à base de PVC et sol-gel avec comme colorant le CR-546 et ETH 4001 ainsi que de les caractériser avec un spectromètre à réflexion (détermination de la linéarité et de la limite de détection par rapport aux analytes éthanol et triméthylamine). Ces tags doivent être intégrés dans un emballage sous vide contenant des produits de pêche et dans une bouteille de verre contenant du jus de fruits. Les résultats doivent être comparés avec ...

  19. Unexpected Reduction of Ethyl 3-Phenylquinoxaline-2- carboxylate 1,4-Di-N-oxide Derivatives by Amines

    Directory of Open Access Journals (Sweden)

    Antonio Monge

    2008-01-01

    Full Text Available The unexpected tendency of amines and functionalized hydrazines to reduceethyl 3-phenylquinoxaline-2-carboxylate 1,4-di-N-oxide (1 to afford a quinoxaline 1c andmono-oxide quinoxalines 1a and 1b is described. The experimental conditions werestandardized to the use of two equivalents of amine in ethanol under reflux for two hours,with the aim of studying the distinct reductive profiles of the amines and thechemoselectivity of the process. With the exception of hydrazine hydrate, which reducedcompound 1 to a 3-phenyl-2-quinoxalinecarbohydrazide derivative, the amines only actedas reducing agents.

  20. Mechanism and Scope of Base-Controlled Catalyst-Free N-Arylation of Amines with Unactivated Fluorobenzenes

    DEFF Research Database (Denmark)

    Jacobsen, Christian Borch; Meldal, Morten Peter; Diness, Frederik

    2017-01-01

    A general method for transition metal-free N-arylation of amines has been developed. Mechanistic studies have revealed that the ability of the base to facilitate the desired amination without promoting unwanted side reactions is the guiding factor. By employing lithium bis(trimethylsilyl)amide as......A general method for transition metal-free N-arylation of amines has been developed. Mechanistic studies have revealed that the ability of the base to facilitate the desired amination without promoting unwanted side reactions is the guiding factor. By employing lithium bis...

  1. Palladium-catalyzed aryl amination-heck cyclization cascade: A one-flask approach to 3-substituted Indoles

    DEFF Research Database (Denmark)

    Jensen, Thomas; Pedersen, Henrik; Bang-Andersen, B.

    2008-01-01

    Two for the price of one: A Pd/dppf-based catalyst provides access to the title compounds from 1,2-dihalogenated aromatic compounds and allylic amines in a single reaction flask. The initial aryl amination step occurs with excellent selectivity for the aryl iodide to ensure the formation of a sin......Two for the price of one: A Pd/dppf-based catalyst provides access to the title compounds from 1,2-dihalogenated aromatic compounds and allylic amines in a single reaction flask. The initial aryl amination step occurs with excellent selectivity for the aryl iodide to ensure the formation...

  2. Important roles of enthalpic and entropic contributions to CO2 capture from simulated flue gas and ambient air using mesoporous silica grafted amines.

    Science.gov (United States)

    Alkhabbaz, Mustafa A; Bollini, Praveen; Foo, Guo Shiou; Sievers, Carsten; Jones, Christopher W

    2014-09-24

    The measurement of isosteric heats of adsorption of silica supported amine materials in the low pressure range (0-0.1 bar) is critical for understanding the interactions between CO2 and amine sites at low coverage and hence to the development of efficient amine adsorbents for CO2 capture from flue gas and ambient air. Heats of adsorption for an array of silica-supported amine materials are experimentally measured at low coverage using a Calvet calorimeter equipped with a customized dosing manifold. In a series of 3-aminopropyl-functionalized silica materials, higher amine densities resulted in higher isosteric heats of adsorption, clearly showing that the density/proximity of amine sites can influence the amine efficiency of adsorbents. In a series of materials with fixed amine loading but different amine types, strongly basic primary and secondary amine materials are shown to have essentially identical heats of adsorption near 90 kJ/mol. However, the adsorption uptakes vary substantially as a function of CO2 partial pressure for different primary and secondary amines, demonstrating that entropic contributions to adsorption may play a key role in adsorption at secondary amine sites, making adsorption at these sites less efficient at the low coverages that are important to the direct capture of CO2 from ambient air. Thus, while primary amines are confirmed to be the most effective amine types for CO2 capture from ambient air, this is not due to enhanced enthalpic contributions associated with primary amines over secondary amines, but may be due to unfavorable entropic factors associated with organization of the second alkyl chain on the secondary amine during CO2 adsorption. Given this hypothesis, favorable entropic factors may be the main reason primary amine based adsorbents are more effective under air capture conditions.

  3. Important Roles of Enthalpic and Entropic Contributions to CO 2 Capture from Simulated Flue Gas and Ambient Air Using Mesoporous Silica Grafted Amines

    KAUST Repository

    Alkhabbaz, Mustafa A.

    2014-09-24

    © 2014 American Chemical Society. The measurement of isosteric heats of adsorption of silica supported amine materials in the low pressure range (0- 0.1 bar) is critical for understanding the interactions between CO2 and amine sites at low coverage and hence to the development of efficient amine adsorbents for CO2 capture from flue gas and ambient air. Heats of adsorption for an array of silica-supported amine materials are experimentally measured at low coverage using a Calvet calorimeter equipped with a customized dosing manifold. In a series of 3-aminopropylfunctionalized silica materials, higher amine densities resulted in higher isosteric heats of adsorption, clearly showing that the density/proximity of amine sites can influence the amine efficiency of adsorbents. In a series of materials with fixed amine loading but different amine types, strongly basic primary and secondary amine materials are shown to have essentially identical heats of adsorption near 90 kJ/mol. However, the adsorption uptakes vary substantially as a function of CO2 partial pressure for different primary and secondary amines, demonstrating that entropic contributions to adsorption may play a key role in adsorption at secondary amine sites, making adsorption at these sites less effi cient at the low coverages that are important to the direct capture of CO2 from ambient air. Thus, while primary amines are confirmed to be the most effective amine types for CO2 capture from ambient air, this is not due to enhanced enthalpic contributions associated with primary amines over secondary amines, but may be due to unfavorable entropic factors associated with organization of the second alkyl chain on the secondary amine during CO2 adsorption. Given this hypothesis, favorable entropic factors may be the main reason primary amine based adsorbents are more effective under air capture conditions.

  4. Amine terminated SAMs: Investigating why oxygen is present in these films

    International Nuclear Information System (INIS)

    Baio, J.E.; Weidner, T.; Brison, J.; Graham, D.J.; Gamble, Lara J.; Castner, David G.

    2009-01-01

    Self-assembled monolayers (SAMs) on gold prepared from amine-terminated alkanethiols have long been employed as model positively charged surfaces. Yet in previous studies significant amounts of unexpected oxygen containing species are always detected in amine terminated SAMs. Thus, the goal of this investigation was to determine the source of these oxygen species and minimize their presence in the SAM. The surface composition, structure, and order of amine-terminated SAMs on Au were characterized by X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectroscopy (ToF-SIMS), sum frequency generation (SFG) and near edge X-ray absorption fine structure (NEXAFS) spectroscopy. XPS determined compositions of amine-terminated SAMs in the current study exhibited oxygen concentrations of 2.4 ± 0.4 atomic %, a substantially lower amount of oxygen than reported in previously published studies. High-resolution XPS results from the S 2p , C 1s and N 1s regions did not detect any oxidized species. Angle-resolved XPS indicated that the small amount of oxygen detected was located at or near the amine head group. Small amounts of oxidized nitrogen, carbon and sulfur secondary ions, as well as ions attributed to water, were detected in the ToF-SIMS data due to the higher sensitivity of ToF-SIMS. The lack of N-O, S-O, and C-O stretches in the SFG spectra are consistent with the XPS and ToF-SIMS results and together show that oxidation of the amine-terminated thiols alone can only account for, at most, a small fraction of the oxygen detected by XPS. Both the SFG and angle-dependent NEXAFS indicated the presence of gauche defects in the amine SAMs. However, the SFG spectral features near 2865 cm -1 , assigned to the stretch of the methylene group next to the terminal amine unit, demonstrate the SAM is reasonably ordered. The SFG results also show another broad feature near 3200 cm -1 related to hydrogen-bonded water. From this multi-technique investigation it is

  5. Safety assessment of the biogenic amines in fermented soya beans and fermented bean curd.

    Science.gov (United States)

    Yang, Juan; Ding, Xiaowen; Qin, Yingrui; Zeng, Yitao

    2014-08-06

    To evaluate the safety of biogenic amines, high performance liquid chromatography (HPLC) was used to evaluate the levels of biogenic amines in fermented soya beans and fermented bean curd. In fermented soya beans, the total biogenic amines content was in a relatively safe range in many samples, although the concentration of histamine, tyramine, and β-phenethylamine was high enough in some samples to cause a possible safety threat, and 8 of the 30 samples were deemed unsafe. In fermented bean curd, the total biogenic amines content was more than 900 mg/kg in 19 white sufu amples, a level that has been determined to pose a safety hazard; putrescine was the only one detected in all samples and also had the highest concentration, which made samples a safety hazard; the content of tryptamine, β-phenethylamine, tyramine, and histamine had reached the level of threat to human health in some white and green sufu samples, and that may imply another potential safety risk; and 25 of the 33 samples were unsafe. In conclusion, the content of biogenic amines in all fermented soya bean products should be studied and appropriate limits determined to ensure the safety of eating these foods.

  6. Amine Landscaping to Maximize Protein-Dye Fluorescence and Ultrastable Protein-Ligand Interaction.

    Science.gov (United States)

    Jacobsen, Michael T; Fairhead, Michael; Fogelstrand, Per; Howarth, Mark

    2017-08-17

    Chemical modification of proteins provides great opportunities to control and visualize living systems. The most common way to modify proteins is reaction of their abundant amines with N-hydroxysuccinimide (NHS) esters. Here we explore the impact of amine number and positioning on protein-conjugate behavior using streptavidin-biotin, a central research tool. Dye-NHS modification of streptavidin severely damaged ligand binding, necessitating development of a new streptavidin-retaining ultrastable binding after labeling. Exploring the ideal level of dye modification, we engineered a panel bearing 1-6 amines per subunit: "amine landscaping." Surprisingly, brightness increased as amine number decreased, revealing extensive quenching following conventional labeling. We ultimately selected Flavidin (fluorophore-friendly streptavidin), combining ultrastable ligand binding with increased brightness after conjugation. Flavidin enhanced fluorescent imaging, allowing more sensitive and specific cell labeling in tissues. Flavidin should have wide application in molecular detection, providing a general insight into how to optimize simultaneously the behavior of the biomolecule and the chemical probe. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  7. Bifunctional (cyclopentadienone)iron-tricarbonyl complexes: Synthesis, computational studies and application in reductive amination

    KAUST Repository

    Moulin, Solenne

    2013-11-15

    Reductive amination under hydrogen pressure is a valuable process in organic chemistry to access amine derivatives from aldehydes or ketones. Knölker\\'s complex has been shown to be an efficient iron catalyst in this reaction. To determine the influence of the substituents on the cyclopentadienone ancillary ligand, a series of modified Knölker\\'s complexes was synthesised and fully characterised. These complexes were also transformed into their analogous acetonitrile iron-dicarbonyl complexes. Catalytic activities of these complexes were evaluated and compared in a model reaction. The scope of this reaction is also reported. For mechanistic insights, deuterium-labelling experiments and DFT calculations were undertaken and are also presented. Festival of amination: Two series of modified Knölker\\'s complexes were synthesised and applied in the reductive amination of various carbonyl derivatives with primary or secondary amines (see scheme, TIPS = triisopropylsilyl). For a mechanistic insight, deuterium-labelling experiments and DFT calculations were undertaken and are also presented. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Investigation of the adsorption of polymer chains on amine-functionalized double-walled carbon nanotubes.

    Science.gov (United States)

    Ansari, R; Ajori, S; Rouhi, S

    2015-12-01

    Molecular dynamics (MD) simulations were used to study the adsorption of different polymer chains on functionalized double-walled carbon nanotubes (DWCNTs). The nanotubes were functionalized with two different amines: NH2 (a small amine) and CH2-NH2 (a large amine). Considering three different polymer chains, all with the same number of atoms, the effect of polymer type on the polymer-nanotube interaction was studied. In general, it was found that covalent functionalization considerably improved the polymer-DWCNT interaction. By comparing the results obtained with different polymer chains, it was observed that, unlike polyethylene and polyketone, poly(styrene sulfonate) only weakly interacts with the functionalized DWCNTs. Accordingly, the smallest radius of gyration was obtained with adsorbed poly(styrene sulfonate). It was also observed that the DWCNTs functionalized with the large amine presented more stable interactions with polyketone and poly(styrene sulfonate) than with polyethylene, whereas the DWCNTs functionalized with the small amine showed better interfacial noncovalent bonding with polyethylene.

  9. Role of the aerosol phase state in ammonia/amines exchange reactions.

    Science.gov (United States)

    Chan, Lap P; Chan, Chak K

    2013-06-04

    The exchange reaction of ammonia in (NH4)2SO4 with an amine and the corresponding reverse reaction of amines in aminium sulfates with ammonia were investigated using an electrodynamic balance coupled with a Raman spectrometer. The temporal changes in particle mass, chemical composition, and phase state were simultaneously monitored. When the salt particles were in an aqueous state at elevated relative humidities (RHs), the exchange of ammonia/amine vapors in the particle phase was reversible. The exchange rates of aqueous particles were in general higher than those of their corresponding solid counterparts. An aqueous phase was essential for the effective displacement of ammonia and amines. Aminium salts in different phase states and with different evaporation characteristics showed remarkably different reaction behaviors in ammonia vapor. The less compact amorphous aminium sulfate solids were more susceptible to ammonia exchange than the crystalline solids. The aminium salts in a liquid state exhibited substantial amine evaporation at reactions. Stable solid salts containing ammonium, aminium, sulfate, and bisulfate were formed and hindered further reactions. The result suggests that ambient aminium sulfates may be acidic. Overall, the phase states of the ammonium and aminium salt particles crucially determine the heterogeneous reaction rates and final product properties and identities.

  10. Cocaine affects foraging behaviour and biogenic amine modulated behavioural reflexes in honey bees

    Directory of Open Access Journals (Sweden)

    Eirik Søvik

    2014-11-01

    Full Text Available In humans and other mammals, drugs of abuse alter the function of biogenic amine pathways in the brain leading to the subjective experience of reward and euphoria. Biogenic amine pathways are involved in reward processing across diverse animal phyla, however whether cocaine acts on these neurochemical pathways to cause similar rewarding behavioural effects in animal phyla other than mammals is unclear. Previously, it has been shown that bees are more likely to dance (a signal of perceived reward when returning from a sucrose feeder after cocaine treatment. Here we examined more broadly whether cocaine altered reward-related behaviour, and biogenic amine modulated behavioural responses in bees. Bees developed a preference for locations at which they received cocaine, and when foraging at low quality sucrose feeders increase their foraging rate in response to cocaine treatment. Cocaine also increased reflexive proboscis extension to sucrose, and sting extension to electric shock. Both of these simple reflexes are modulated by biogenic amines. This shows that systemic cocaine treatment alters behavioural responses that are modulated by biogenic amines in insects. Since insect reward responses involve both octopamine and dopamine signalling, we conclude that cocaine treatment altered diverse reward-related aspects of behaviour in bees. We discuss the implications of these results for understanding the ecology of cocaine as a plant defence compound. Our findings further validate the honey bee as a model system for understanding the behavioural impacts of cocaine, and potentially other drugs of abuse.

  11. Cocaine affects foraging behaviour and biogenic amine modulated behavioural reflexes in honey bees.

    Science.gov (United States)

    Søvik, Eirik; Even, Naïla; Radford, Catherine W; Barron, Andrew B

    2014-01-01

    In humans and other mammals, drugs of abuse alter the function of biogenic amine pathways in the brain leading to the subjective experience of reward and euphoria. Biogenic amine pathways are involved in reward processing across diverse animal phyla, however whether cocaine acts on these neurochemical pathways to cause similar rewarding behavioural effects in animal phyla other than mammals is unclear. Previously, it has been shown that bees are more likely to dance (a signal of perceived reward) when returning from a sucrose feeder after cocaine treatment. Here we examined more broadly whether cocaine altered reward-related behaviour, and biogenic amine modulated behavioural responses in bees. Bees developed a preference for locations at which they received cocaine, and when foraging at low quality sucrose feeders increase their foraging rate in response to cocaine treatment. Cocaine also increased reflexive proboscis extension to sucrose, and sting extension to electric shock. Both of these simple reflexes are modulated by biogenic amines. This shows that systemic cocaine treatment alters behavioural responses that are modulated by biogenic amines in insects. Since insect reward responses involve both octopamine and dopamine signalling, we conclude that cocaine treatment altered diverse reward-related aspects of behaviour in bees. We discuss the implications of these results for understanding the ecology of cocaine as a plant defence compound. Our findings further validate the honey bee as a model system for understanding the behavioural impacts of cocaine, and potentially other drugs of abuse.

  12. pH-sensitive diamond field-effect transistors (FETs) with directly aminated channel surface

    International Nuclear Information System (INIS)

    Song, Kwang-Soup; Nakamura, Yusuke; Sasaki, Yuichi; Degawa, Munenori; Yang, Jung-Hoon; Kawarada, Hiroshi

    2006-01-01

    We have introduced pH sensors fabricated on diamond thin films through modification of the surface-terminated atom. We directly modified the diamond surface from hydrogen to amine or oxygen with ultraviolet (UV) irradiation under ammonia gas. The quantified amine site based on the spectra obtained by X-ray photoelectron spectroscopy (XPS) is 26% (2.6 x 10 14 cm -2 ) with UV irradiation for 8 h and its coverage is dependent on the UV irradiation time. This directly aminated diamond surface is stable with long-term exposure in air and electrolyte solution. We fabricated diamond solution-gate field-effect transistors (SGFETs) without insulating layers on the channel surface. These diamond SGFETs with amine modified by direct amination are sensitive to pH (45 mV/pH) over a wide range from pH 2 to 12 and their sensitivity is dependent on the density of binding sites corresponding to UV irradiation time on the channel surface

  13. Nitrosatable amines and nitrosamide formation in natural stimulants: Cola acuminata, C. nitida and Garcinia cola.

    Science.gov (United States)

    Atawodi, S E; Mende, P; Pfundstein, B; Preussmann, R; Spiegelhalder, B

    1995-08-01

    Three varieties of kola nut, Cola acuminata, C. nitida and Garcinia cola, of Nigerian origin, were analysed for their content of primary and secondary amines, and assessed for their relative methylating potential due to nitrosamide formation. Primary and secondary amines were determined as benzene sulfonamides by gas chromatography/thermal energy analysis (GC/TEA). Dimethylamine, methylamine, ethylamine and isopentylamine were detected in all kola nut varieties, while pyrrolidine, piperidine and isobutylamine were detected in one or more varieties. Estimated average total daily intake of aliphatic amines by a typical kola nut chewer varied from 260 to 1040 micrograms/day for secondary amines and from 2430 to 9710 micrograms/day for primary amines. Methylating activity of the nitrosated kola nuts, expressed as N-nitroso-N-methylurea equivalents, was also determined by GC/TEA. Methylating activity was significantly higher in kola nuts (170-490 micrograms/kg) than has ever been reported for a fresh plant product. These data suggest that the possible role of kola nut chewing in human cancer aetiology should be explored in countries where kola nuts are widely consumed as stimulants.

  14. Comprehensive, structurally-informed alignment and phylogeny of vertebrate biogenic amine receptors

    Directory of Open Access Journals (Sweden)

    Stephanie J. Spielman

    2015-02-01

    Full Text Available Biogenic amine receptors play critical roles in regulating behavior and physiology in both vertebrates and invertebrates, particularly within the central nervous system. Members of the G-protein coupled receptor (GPCR family, these receptors interact with endogenous bioamine ligands such as dopamine, serotonin, and epinephrine, and are targeted by a wide array of pharmaceuticals. Despite the clear clinical and biological importance of these receptors, their evolutionary history remains poorly characterized. In particular, the relationships among biogenic amine receptors and any specific evolutionary constraints acting within distinct receptor subtypes are largely unknown. To advance and facilitate studies in this receptor family, we have constructed a comprehensive, high-quality sequence alignment of vertebrate biogenic amine receptors. In particular, we have integrated a traditional multiple sequence approach with robust structural domain predictions to ensure that alignment columns accurately capture the highly-conserved GPCR structural domains, and we demonstrate how ignoring structural information produces spurious inferences of homology. Using this alignment, we have constructed a structurally-partitioned maximum-likelihood phylogeny from which we deduce novel biogenic amine receptor relationships and uncover previously unrecognized lineage-specific receptor clades. Moreover, we find that roughly 1% of the 3039 sequences in our final alignment are either misannotated or unclassified, and we propose updated classifications for these receptors. We release our comprehensive alignment and its corresponding phylogeny as a resource for future research into the evolution and diversification of biogenic amine receptors.

  15. Reduced Reactivity of Amines against Nucleophilic Substitution via Reversible Reaction with Carbon Dioxide.

    Science.gov (United States)

    Mohammed, Fiaz S; Kitchens, Christopher L

    2015-12-23

    The reversible reaction of carbon dioxide (CO₂) with primary amines to form alkyl-ammonium carbamates is demonstrated in this work to reduce amine reactivity against nucleophilic substitution reactions with benzophenone and phenyl isocyanate. The reversible formation of carbamates has been recently exploited for a number of unique applications including the formation of reversible ionic liquids and surfactants. For these applications, reduced reactivity of the carbamate is imperative, particularly for applications in reactions and separations. In this work, carbamate formation resulted in a 67% reduction in yield for urea synthesis and 55% reduction for imine synthesis. Furthermore, the amine reactivity can be recovered upon reversal of the carbamate reaction, demonstrating reversibility. The strong nucleophilic properties of amines often require protection/de-protection schemes during bi-functional coupling reactions. This typically requires three separate reaction steps to achieve a single transformation, which is the motivation behind Green Chemistry Principle #8: Reduce Derivatives. Based upon the reduced reactivity, there is potential to employ the reversible carbamate reaction as an alternative method for amine protection in the presence of competing reactions. For the context of this work, CO₂ is envisioned as a green protecting agent to suppress formation of n-phenyl benzophenoneimine and various n-phenyl-n-alky ureas.

  16. Tertiary-amine-containing thermo- and pH-sensitive hydrophilic ABA triblock copolymers: effect of different tertiary amines on thermally induced sol-gel transitions.

    Science.gov (United States)

    Henn, Daniel M; Wright, Roger A E; Woodcock, Jeremiah W; Hu, Bin; Zhao, Bin

    2014-03-11

    This Article reports on the synthesis of a series of well-defined, tertiary-amine-containing ABA triblock copolymers, composed of a poly(ethylene oxide) (PEO) central block and thermo- and pH-sensitive outer blocks, and the study of the effect of different tertiary amines on thermally induced sol-gel transition temperatures (T(sol-gel)) of their 10 wt % aqueous solutions. The doubly responsive ABA triblock copolymers were prepared from a difunctional PEO macroinitiator by atom transfer radical polymerization of methoxydi(ethylene glycol) methacrylate and ethoxydi(ethylene glycol) methacrylate at a feed molar ratio of 30:70 with ∼5 mol % of either N,N-diethylaminoethyl methacrylate (DEAEMA), N,N-diisopropylaminoethyl methacrylate, or N,N-di(n-butyl)aminoethyl methacrylate. The chain lengths of thermosensitive outer blocks and the molar contents of tertiary amines were very similar for all copolymers. Using rheological measurements, we determined the pH dependences of T(sol-gel) of 10 wt % aqueous solutions of these copolymers in a phosphate buffer. The T(sol-gel) versus pH curves of all polymers exhibited a sigmoidal shape. The T(sol-gel) increased with decreasing pH; the changes were small on both high and low pH sides. At a specific pH, the T(sol-gel) decreased with increasing the hydrophobicity of the tertiary amine, and upon decreasing pH the onset pH value for the T(sol-gel) to begin to increase noticeably was lower for the more hydrophobic tertiary amine-containing copolymer. In addition, we studied the effect of different tertiary amines on the release behavior of FITC-dextran from 10 wt % micellar gels in an acidic medium at 37 and 27 °C. The release profiles for three studied hydrogels at 37 °C were essentially the same, suggesting that the release was dominated by the diffusion of FITC-dextran. At 27 °C, the release was significantly faster for the DEAEMA-containing copolymer, indicating that both diffusion and gel dissolution contributed to the

  17. Chemoenzymatic dynamic kinetic resolution of primary amines using a recyclable palladium nanoparticle catalyst together with lipases.

    Science.gov (United States)

    Gustafson, Karl P J; Lihammar, Richard; Verho, Oscar; Engström, Karin; Bäckvall, Jan-E

    2014-05-02

    A catalyst consisting of palladium nanoparticles supported on amino-functionalized siliceous mesocellular foam (Pd-AmP-MCF) was used in chemoenzymatic dynamic kinetic resolution (DKR) to convert primary amines to amides in high yields and excellent ee's. The efficiency of the nanocatalyst at temperatures below 70 °C enables reaction conditions that are more suitable for enzymes. In the present study, this is exemplified by subjecting 1-phenylethylamine (1a) and analogous benzylic amines to DKR reactions using two commercially available lipases, Novozyme-435 (Candida antartica Lipase B) and Amano Lipase PS-C1 (lipase from Burkholderia cepacia) as biocatalysts. The latter enzyme has not previously been used in the DKR of amines because of its low stability at temperatures over 60 °C. The viability of the heterogeneous Pd-AmP-MCF was further demonstrated in a recycling study, which shows that the catalyst can be reused up to five times.

  18. Resolution of water in crude oil emulsion by some novel aromatic amine polyesters

    Directory of Open Access Journals (Sweden)

    A.M. Al-Sabagh

    2015-09-01

    Full Text Available In this work, three aromatic amines (p-toluidine, p-nitroaniline and p-chloroaniline were chosen as bases for the repatriation of some nonionic polyesters. These amines were ethoxylated with different total number of ethylene oxide units 6, 12, 18. The prepared ethoxylated amine diols were polyesterified with maleic anhydride and polypropylene oxide polyethylene oxide block copolymers in polyesterification reaction. The demulsification efficiency of these demulsifiers was investigated using the bottle test. The effects of the molecular weight, concentration, asphaltene content, water content, Hydrophile Lipophile Balance (HLB and temperature on the demulsification efficiency were investigated. The surface active properties were correlated with their demulsification efficiency. It was found that, NAE18D gave the best result in the demulsification process. The demulsification efficiency was discussed on the light of surface active properties, interfacial tension and the factors affecting the demulsification. The surface-active properties of the prepared demulsifiers were measured at 60 °C.

  19. Diamond surface functionalization with biomimicry – Amine surface tether and thiol moiety for electrochemical sensors

    Energy Technology Data Exchange (ETDEWEB)

    Sund, James B., E-mail: jim@jamessund.com [Department of Electrical and Computer Engineering, Duke University, Durham, NC (United States); Causey, Corey P. [Departments of Chemistry and Biochemistry, Duke University, Durham, NC (United States); Wolter, Scott D. [Department of Physics, Elon University, Elon, NC 27244 (United States); Parker, Charles B., E-mail: charles.parker@duke.edu [Department of Electrical and Computer Engineering, Duke University, Durham, NC (United States); Stoner, Brian R. [Department of Electrical and Computer Engineering, Duke University, Durham, NC (United States); Research Triangle Institute (RTI) International, Research Triangle Park, NC (United States); Toone, Eric J. [Departments of Chemistry and Biochemistry, Duke University, Durham, NC (United States); Glass, Jeffrey T. [Department of Electrical and Computer Engineering, Duke University, Durham, NC (United States)

    2014-05-01

    Highlights: • Diamond surfaces were functionalized with organic molecules using a novel approach. • Used biomimicry to select a molecule to bind NO, similar to the human body. • Molecular orbital theory predicted the molecule-analyte oxidation behavior. • A thiol moiety was attached to an amine surface tether on the diamond surface. • XPS analysis verified each surface functionalization step. - Abstract: The surface of conducting diamond was functionalized with a terminal thiol group that is capable of binding and detecting nitrogen–oxygen species. The functionalization process employed multiple steps starting with doped diamond films grown by plasma enhanced chemical vapor deposition followed by hydrogen termination and photochemical attachment of a chemically protected amine alkene. The surface tether was deprotected to reveal the amine functionality, which enabled the tether to be extended with surface chemistry to add a terminal thiol moiety for electrochemical sensing applications. Each step of the process was validated using X-ray photoelectron spectroscopy analysis.

  20. “COLATURA DI ALICI “ CETARESE: EVALUATION OF AMINIC PROFILE

    Directory of Open Access Journals (Sweden)

    A Anastasio

    2008-12-01

    Full Text Available “Colatura d’alici”is a speciality made in Cetara, a clear ,amber-coloured liquid that has sharp taste, prepared with the juice coming from the anchovy salting process. The anchovies are caught in the Gulf of Salerno between the mounths of March and July. The colatura is ready at the beginning of December. Histamine poisoning, a food-borne chemical intoxication caused by the consumption of food containing toxic levels of histamine, is a syndrome commonly associated with the consumption of seafood beloging to the Engraulidae and some fish families. Histamine and biogenic amine levels were determined in “colatura di alici di Cetara”. The amine was separated in a HPLC/FL system. Histamine level were lower than the law limits only in one of the examinated products. A reduction of the histamine and amine levels in colatura cetarese can be obtained using a determinate salt concentrations and changing way of seasoning.