Search results for "Quenching"

showing 10 items of 275 documents

Properties of a triazolopyridine system as a molecular chemosensor for metal ions, anions, and amino acids.

2006

The characteristics as a chemosensor of the compound 3-methyl-6,8-di(2-pyridyl)-[1,2,3]triazolo[5',1':6,1]pyrido[2,3-]pyrimidine (1) have been analyzed. Interaction with Cu(2+) produces a quenching of the fluorescence, while interaction with Zn(2+) leads to a quenching of the fluorescence followed by a bathochromic shift. The crystal structure of the Zn(1)(H(2)O)(3)(ClO(4))(2) x H(2)O complex shows the coordination of Zn(2+) through the terpyridine moiety. The octahedral site is completed by three water molecules. Interactions of the Zn(2+) complex with the anions sulfate, nitrate, nitrite, and dihydrogenphosphate in ethanol produce hypsochromic shifts and restoration of the fluorescence wh…

inorganic chemicalsAnionsQuenching (fluorescence)ChemistryPyridinesMetal ions in aqueous solutionOrganic ChemistryInorganic chemistryCrystallography X-RayMedicinal chemistrychemistry.chemical_compoundSpectrometry FluorescenceMetalsCationsBathochromic shiftMoleculeMoietyTriazolopyridineHypsochromic shiftSpectrophotometry UltravioletTerpyridineAmino AcidsThe Journal of organic chemistry
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Open-chain polyamine ligands bearing an anthracene unit - Chemosensors for logic operations at the molecular level

2001

In this work the absorption and the fluorescence emission properties as well as the protonation sequence of three open chain polyamine ligands of different dimensions bearing an anthracene unit were studied. The protonation and stability constants with Ni2+, Cu2+, Zn2+, and Cd2+ have been determined in 0.15 mol·dm−3 NaCl at 298.1 ± 0.1 K. The values of both protonation and stability constants follow the expected trends according to the number of nitrogen donors, sequence of chelate rings and hydrophilic−hydrophobic balance. Chelation enhancement of the fluorescence emission (CHEF) was observed for some complexes of these ligands with Zn2+ and Cd2+. In contrast the analog complexes containin…

inorganic chemicalsAnthraceneQuenching (fluorescence)Inorganic chemistrychemistry.chemical_elementProtonationFluorescenceCopperInorganic ChemistryMetalchemistry.chemical_compoundCrystallographychemistryvisual_artvisual_art.visual_art_mediumChelationAbsorption (chemistry)
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A new simple chromo-fluorogenic probe for NO2 detection in air.

2015

[EN] A new chromo-fluorogenic probe, consisting of a biphenyl derivative containing both a silylbenzyl ether and a N,N-dimethylamino group, for NO2 detection in the gas phase has been developed. A clear colour change from colourless to yellow together with an emission quenching was observed when the probe reacted with NO2. A limit of detection to the naked eye of about 0.1 ppm was determined and the system was successfully applied to the detection of NO2 in realistic atmospheric conditions.

inorganic chemicalsGas phase reactionsAnalytical chemistryEtherPhotochemistryNO2Nitric Oxidecomplex mixturesCatalysisGas phasechemistry.chemical_compoundQUIMICA ORGANICAChromogenic detectionFluorescent DyesDetection limitBiphenylEmission quenchingSIMPLE (dark matter experiment)Molecular StructureSensorsAirOrganic ChemistryQUIMICA INORGANICAGeneral Chemistryrespiratory systemchemistryChromogenic CompoundsNaked eyeDerivative (chemistry)Chemistry (Weinheim an der Bergstrasse, Germany)
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A M�ssbauer and ESR study of LiNbO3-Fe2O3 for low Fe2O3 concentrations

1989

Samples of the system LiNbO3-Fe2O3 prepared by water quenching and by the double-roller quenching method in the range up to 24 mol% Fe2O3 were investigated by Mossbauer and ESR spectroscopy. In the water quenched samples up to 11 mol% Fe2O3 only the Fe3+ and the Fe2+ valence states could be detected. The Fe2+ concentration decreased with increasing Fe2O3 content. Above 11 mol% Fe2O3 magnetically split Mossbauer spectra indicated the presence of Fe2O3 clusters. The isomer shift values of Fe3+ as a function of Fe2O3 concentration showed jumps at 6 and 11 mol% Fe2O3, whereas no significant changes could be detected in the quadrupole splitting values. The ESR data already exhibited the existenc…

inorganic chemicalschemistry.chemical_classificationQuenchingValence (chemistry)Physics and Astronomy (miscellaneous)General EngineeringAnalytical chemistryGeneral ChemistryQuadrupole splittingIonlaw.inventionNuclear magnetic resonancechemistrylawMössbauer spectroscopyGeneral Materials ScienceElectron paramagnetic resonanceSpectroscopyInorganic compoundApplied Physics A Solids and Surfaces
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Sensitivity of jet quenching to enhancement of the medium opacity near TC

2014

[Introduction] One of the main goals of the study of high transverse momentum ( P T ) observables in the context of ultrarelativistic heavy-ion collisions is the determination of properties of QCD matter. In particular, the transport coefficients ˆ q and ˆ e characterizing the interaction of the medium with a high p T parton are accessible via hard probes. However, a precision extraction of their temperature dependence from current data faces the problem that neither the space-time geometry of the evolving matter nor the link between thermodynamics and transport coefficients is unambiguously known. Thus, various conjectured scenarios exist for how thermodynamics and transport coefficients b…

jet quenchingcritical temperatureopacitymedium opacity
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Extracting qˆ in event-by-event hydrodynamics and the centrality/energy puzzle

2017

In our analysis, we combine event-by-event hydrodynamics, within the EKRT formulation, with jet quenching -ASW Quenching Weights- to obtain high- for charged particles at RHIC and LHC energies for different centralities. By defining a K-factor that quantifies the departure of from an ideal estimate, , we fit the single-inclusive experimental data for charged particles. This K-factor is larger at RHIC than at the LHC but, surprisingly, it is almost independent of the centrality of the collision. peerReviewed

jet quenchingenergy lossevent-by-event hydrodynamicsNuclear Experiment
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"Figure 1a" of "Azimuthal anisotropy of neutral pion production in Au+Au collisions at $\sqrt(s_NN)$ = 200 GeV: Path-length dependence of jet quenchi…

2023

Ratios of $v_2$ measured separately using MPC and RXN$_{in}$ to combine results.

jet quenchingpath-length dependenceAu Au --> $\pi^0$azimuthal anisotropyppg110200.0
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"Figure 2a-1" of "Azimuthal anisotropy of neutral pion production in Au+Au collisions at $\sqrt(s_NN)$ = 200 GeV: Path-length dependence of jet quenc…

2023

$v_2$ vs $N_{part}$ and $R_{AA}$ vs $N_{part}$ in two $p_T$ ranges compared with WHDG model.

jet quenchingpath-length dependenceAu Au --> $\pi^0$azimuthal anisotropyppg110200.0
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"Figure 2a-2" of "Azimuthal anisotropy of neutral pion production in Au+Au collisions at $\sqrt(s_NN)$ = 200 GeV: Path-length dependence of jet quenc…

2023

$v_2$ vs $N_{part}$ in two $p_T$ ranges and $R_{AA}$ vs $N_{part}$ in the same $p_T$ ranges.

jet quenchingpath-length dependenceAu Au --> $\pi^0$azimuthal anisotropyppg110200.0
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"Figure 2a-3" of "Azimuthal anisotropy of neutral pion production in Au+Au collisions at $\sqrt(s_NN)$ = 200 GeV: Path-length dependence of jet quenc…

2023

$v_2$ vs $N_{part}$ in two $p_T$ ranges and $R_{AA}$ vs $N_{part}$ in the same $p_T$ ranges.

jet quenchingpath-length dependenceAu Au --> $\pi^0$azimuthal anisotropyppg110200.0
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