Search results for "TRIP"

EXAFS and XRD study of Pd–Ag bimetallic catalysts supported on pumice from organometallic precursors

2001

Abstract Silver–palladium bimetallic catalysts were supported on pumice following different procedures, based on mild treatments of organometallic precursors. The experiments for the structural characterization of the synthesized samples, wide angle X-ray diffraction (XRD) and X-ray absorption spectroscopy, were carried out at the beamline GILDA of the European Synchrotron Radiation Facility. The analysis of the data demonstrated that alloying took place with a degree of homogeneity depending on the different preparation routes.

Regio(ir)regular naphthalenediimide- and perylenediimide-bithiophene copolymers: How MO localization controls the bandgap

2016

Absorption spectra of regio(ir)regular naphthalenediimide (NDI)- and perylenediimide (PDI)-bithiophene (2T) donor/acceptor (D/A) copolymers are surprisingly similar despite cross-conjugation in the regioirregular structures. This result is traced back to largely localized frontier molecular orbitals (FMOs) as revealed by (time-dependent) DFT calculations. Interestingly, while the FMOs of the P(PDI-2T) copolymer are localized solely in the PDI units, they are predominantly localized in the respective D/A units of the P(NDI-2T) copolymer. The pronounced CT character of the lowest singlet state in P(NDI-2T) should give rise to a close lying CT triplet state, generating small singlet–triplet ga…

L'apprendimento e l'insegnamento dell'italiano come LS per gli arabofoni. Un'indagine svolta in Libia

Metabolic shift of polyphosphate-accumulating organisms with different levels of polyphosphate storage

2012

Previous studies have shown that polyphosphate-accumulating organisms (PAOs) are able to behave as glycogen-accumulating organisms (GAOs) under different conditions. In this study we investigated the behavior of a culture enriched with Accumulibacter at different levels of polyphosphate (poly-P) storage. The results of stoichiometric ratios Gly degraded/HAc uptake, PHB synthesized/HAc uptake, PHV synthesized/HAc uptake and P release/HAc uptake confirmed a metabolic shift from PAO metabolism to GAO metabolism: PAOs with high poly-P content used the poly-P to obtain adenosine tri-phosphate (ATP), and glycogen (Gly) to obtain nicotinamide adenine dinucleotide (NADH) and some ATP. In a test whe…

Determination of Cd, Cu, Pb and Zn content of infant formulas by differential pulse anodic stripping voltammetry (DPASV).

1994

The differential pulse anodic stripping voltammetry (DPASV) method described is based on the one reported by Hasse et al., but adapted to normal laboratory conditions. The values obtained in the estimation of the analytical parameters (linearity, detection and quantification limits, precision and accuracy) show that in the conditions described the method is sensitive enough, reliable and useful for determining these elements in infant formulas. A comparison between DPASV and atomic absorption spectroscopy (AAS) methods in the conditions described here shows that the former is less sensitive but that they are similar in precision. The cadmium, copper, lead and zinc contents of different type…

Experimental and robust modeling approach for lead(II) uptake by alginate gel beads: influence of the ionic strength and medium composition.

2014

Abstract Systematic kinetic and equilibrium studies on the lead ions removal ability by Ca-alginate gel beads have been performed by varying several internal parameters, namely, number of gel beads, nature and composition of the ionic medium and pH, which allowed us to model a wastewater in order to closely reproduce the composition of a real sample. Moreover, the effects brought about the different ionic species present in the reacting medium have been evaluated. Differential Pulse Anodic Stripping Voltammetry (DP-ASV), has been systematically used to perform kinetic and equilibrium measurements over continuous time in a wide range of concentration. Kinetic and equilibrium data have been q…

1966

Die spontane Autoxydation N,N-dialkylierter Arylamine verlauft langsam. Sie wird durch Essigsaure, Azoisobuttersauredinitril (AIBN), Kobaltverbindungen, Benzylchlorid und Essigsaureanhydrid beschleunigt. Essigsaureanhydrid uberfuhrt die als Inhibitoren sehr wirksamen, durch oxydative Entalkylierung entstandenen sek. Amine in die als Inhibitoren wirkungslosen N-Acetylderivate (Ausbeute bis 90%). Die bei der Autoxydation als Kettentrager wirksamen Aminohydroperoxyde I konnen (a) durch Kondensation in die Dialkylperoxyde II ubergefuhrt und (b) durch Triphenylphosphin desoxygeniert werden. Die Amindialkylperoxyde II lassen sich in Substanz aus den Autoxydationsansatzen isolieren. AIBN lost unte…

Multi-mycotoxin analysis in wheat semolina using an acetonitrile-based extraction procedure and gas chromatography–tandem mass spectrometry

2012

A new analytical method for the rapid and simultaneous determination of ten mycotoxins including patulin, zearalenone and eight trichothecenes (nivalenol, fusarenon-X, diacetoxyscirpenol, 3-acetyl-deoxynivalenol, neosolaniol, deoxynivalenol, T-2 and HT-2) in wheat semolina has been developed and optimized. Sample extraction and purification were performed with a modified QuEChERS-based (acronym of Quick, Easy, Cheap, Effective, Rugged and Safe) procedure and determined by gas chromatography (GC) coupled to triple quadrupole instrument (QqQ). This is the first paper on the application of GC-QqQ-MS/MS to analysis of mycotoxins. Careful optimization of the gas chromatography-tandem mass spectr…

New Fluorinated Peptidomimetics through Tandem Aza-Michael Addition to α-Trifluoromethyl Acrylamide Acceptors: Synthesis and Conformational Study in …

2009

A range of partially modified retro (PMR) psi[NHCH(2)] peptide mimetics containing a hydrolytically stable CH(2)CH(CF(3))CO unit have been synthesized. The first kind of peptidomimetics is obtained from the highly efficient aza-Michael addition of different amines to alpha-trifluoromethyl acrylamide acceptors. Subsequent deprotection of the amino group furnishes the key common intermediate for the synthesis of other families of peptidomimetics: dipeptides, tripeptides, peptidomimetics containing a urea moiety, and structures containing two units of alpha-trifluoromethyl-beta(2)-alanine. Finally, a conformational study of several of the newly synthesized peptidomimetics, performed with the a…

1985

Etude de polyesters avec du triphenylene ou du benzene comme cœur du discogene et des espaces flexibles alkylene