Search results for "ECU"

showing 10 items of 42395 documents

Bowl-shape electron donors with absorptions in the visible range of the solar spectrum and their supramolecular assemblies with C 60

2012

We describe the synthesis, electronic, optical and photophysical properties of a family of three electron-donor bowl-shaped organic molecules that absorb light in the whole range of the visible spectrum (up to 800 nm in one case), and associate C60 in solution with binding constants in the range of 104–102 M−1 as measured from both UV-vis and fluorescence titrations in several solvents. These molecules are π-extended derivatives of tetrathiafulvalene, based on a truxene core to which two or three units of dithiole are covalently attached. The inclusion of the bulky dithiole groups is responsible for their bowl-shape geometry, which allows them to associate with C60, and their electron-donor…

010405 organic chemistrySupramolecular chemistryGeneral Chemistry010402 general chemistryPhotochemistry01 natural sciences0104 chemical sciencesPhotoexcitationchemistry.chemical_compoundchemistryIntramolecular forceUltrafast laser spectroscopyDensity functional theoryAbsorption (chemistry)TetrathiafulvaleneVisible spectrum
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Encapsulation of tetramethylphosphonium cations

2009

International audience; The weak interactions and capsule formation of tetramethylphosphonium (TMP) cation with resorcinarenes 1 and 2 and the corresponding pyrogallarenes 3 and 4 were studied in the solid state by single crystal X-ray diffraction, in solution by NMR and in the gas phase by mass spectrometry. In methanol-D4, the NMR titration studies reveal that the association constants for the 1:1 complexes of TMP@3 and TMP@4 are much higher (TMP@4:390±37 M-1) than for the corresponding TMP@1 and TMP@2 (TMP@2:130±10 M-1) complexes. In the gas phase both monomeric 1:1 TMP@1-TMP@4 complexes as well as the dimeric 1:2 capsule complexes, TMP@12-TMP@42 were observed. The 1:1:2 molar mixtures o…

010405 organic chemistrySupramolecular chemistrySolid-stateGeneral Chemistry010402 general chemistryMass spectrometry01 natural sciences0104 chemical sciences3. Good healthGas phasechemistry.chemical_compoundCrystallographyMonomerchemistryPhysical SciencesNmr titrationX-ray crystallographyMethanolSupramolecular Chemistry
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Microporous Triptycene‐Based Affinity Materials on Quartz Crystal Microbalances for Tracing of Illicit Compounds

2019

Triptycene-based organic molecules of intrinsic microporosity (OMIMs) with extended functionalized π-surfaces are excellent materials for gas sorption and separation. In this study, the affinities of triptycene-based OMIM affinity materials on 195 MHz high-fundamental-frequency quartz crystal microbalances (HFF-QCMs) for hazardous and illicit compounds such as piperonal and (-)-norephedrine were determined. Both new and existing porous triptycene-based affinity materials were investigated, resulting in very high sensitivities and selectivities that could be applied for sensing purposes. Remarkable results were found for safrole - a starting material for illicit compounds such as ecstasy. A …

010405 organic chemistrySupramolecular chemistrySorptionGeneral ChemistryMicroporous material010402 general chemistry01 natural sciencesCombinatorial chemistry0104 chemical sciencesCrystalchemistry.chemical_compoundPiperonalchemistryTriptycenePorosityQuartzChemPlusChem
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Modulating the DNA cleavage ability of copper(II) Schiff bases through ternary complex formation

2018

Copper(II) complexes with the potentially tridentate Schiff bases N-[(3-ethoxy-2-hydroxyphenyl)methylidene]-N′-tosylbenzene-1,2-diamine (H2L1) and N-[(2-hydroxynaphthanyl)methylidene]-N′-tosylbenzene-1,2-diamine (H2L2) have been synthesized by electrochemical oxidation of the metal in an electrochemical cell containing a solution of the corresponding ligand in acetonitrile. Adducts of these compounds with 2,2′-bipyridine (2,2′-bpy), 4,4′-bipyridine (4,4′-bpy) or 1,10-phenanthroline (phen) were also obtained. The complexes have been characterized by microanalysis, mass spectrometry, EPR, IR and UV-Vis spectroscopies, as well as DFT calculations. The ligand H2L1 and the compounds [CuL1(H2O)]·…

010405 organic chemistrySupramolecular chemistrychemistry.chemical_elementNANOPARTÍCULASGeneral Chemistry010402 general chemistry01 natural sciencesCopperCatalysisSquare pyramidal molecular geometry0104 chemical scienceslaw.inventionAdductMetalCrystallographychemistry.chemical_compoundchemistrylawvisual_artMaterials Chemistryvisual_art.visual_art_mediumElectron paramagnetic resonanceAcetonitrileTernary complex
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A Ferrocenyl Amino Substituted Stannylene as an Intramolecular Fe→Sn Lewis Adduct

2018

010405 organic chemistrychemistry.chemical_element010402 general chemistry01 natural sciencesMedicinal chemistry0104 chemical sciencesAdductInorganic Chemistrychemistry.chemical_compoundchemistryFerroceneIntramolecular forceLewis acids and basesTinZeitschrift für anorganische und allgemeine Chemie
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Magneto-structural correlations in asymmetric oxalato-bridged dicopper(II) complexes with polymethyl-substituted pyrazole ligands

2018

Two oxalato-bridged dinuclear copper(II) complexes, [{Cu(Hdmpz)3}2(μ-ox)](ClO4)2·2H2O (1) and [{Cu(Htmpz)3}2(μ-ox)](ClO4)2·2H2O (2) (Hdmpz = 3,5-dimethyl-1H-pyrazole and Htmpz = 3,4,5-trimethyl-1H-pyrazole), have been synthesized and structurally and magnetically characterized. The crystal structures of 1 and 2 consist of asymmetric bis-bidentate μ-oxalatodicopper(II) complex cations with two short [Cu–O = 1.976(2) (1) and 1.973(2) Å (2)] and two long copper–oxygen bonds [Cu–O = 2.122(2) (1) and 2.110(2) Å (2)]. The environment at each CuII ion in 1 and 2 is closer to the trigonal bipyramidal geometry than to the square pyramidal [τ = 0.633 (1) and 0.711 (2)]. The magnetic properties of 1 a…

010405 organic chemistrychemistry.chemical_elementCrystal structurePyrazole ligandsPyrazole010402 general chemistry01 natural sciencesCopperSquare pyramidal molecular geometryAntiferromagnetic coupling0104 chemical sciencesIonCrystallographychemistry.chemical_compoundTrigonal bipyramidal molecular geometrychemistryMaterials ChemistryPhysical and Theoretical Chemistry
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Synthesis, crystal structure and magnetic properties of the cyclic tetranuclear compound [Cu4(pz)4(hppa)2(H2O)4] [pz = pyrazolate; hppa = R,S-2-hydro…

2019

Abstract The synthesis, X-ray structure and magnetic properties of the neutral tetranuclear copper(II) complex of formula [Cu4(pz)4(hppa)2(H2O)4] (1) [Hpz = pyrazole and hppa = R,S-2-hydroxo-2-phenyl-2-(1-pyrazolyl)acetate] are reported. Remarkably, the structure of 1 reveals the presence of the S- and R-forms of the new hppa ligand which is formed in situ in the complex reaction between copper(II), pyrazole and phenylmalonate in water:methanol solvent mixture under ambient conditions. The two crystallographically independent copper(II) ions [Cu(1)/Cu(2)] are five-coordinate in square pyramidal surroundings. Three nitrogen atoms, from two pz groups and one hppa ligand and one oxygen atom of…

010405 organic chemistrychemistry.chemical_elementCrystal structurePyrazole010402 general chemistry01 natural sciencesMagnetic susceptibilityCopperSquare pyramidal molecular geometry0104 chemical sciencesInorganic Chemistrychemistry.chemical_compoundCrystallographychemistryMaterials ChemistryAntiferromagnetismMoleculeCarboxylatePhysical and Theoretical ChemistryPolyhedron
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The MIRS computer package for modeling the rovibrational spectra of polyatomic molecules

2003

International audience; The MIRS spectroscopic software for the modeling of ro-vibrational spectra of polyatomic molecules is presented. It is designed for the global treatment of complex band systems of molecules to take full account of symmetry properties. It includes e cient algorithms based on the irreducible tensor formalism. Predictions and simultaneous data fi tting (positions and intensities) are implemented as well as advanced options related to group theory algebra. Illustrative examples on CH3D, CH4, CH3Cl and PH3 are reported and the present status of data available is given. It is written in C++ for standard PC computer operating under Windows. The full package including on-lin…

010504 meteorology & atmospheric sciences01 natural sciencesSpectral lineSoftwareComputer package0103 physical sciencesMoleculeSpectroscopy0105 earth and related environmental sciencesPhysics[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]RadiationSpectroscopic database010304 chemical physicsbusiness.industryPolyatomic ionRotational–vibrational spectroscopyMolecular spectroscopyAtmospheric applicationsAtomic and Molecular Physics and OpticsComputational physics[ PHYS.PHYS.PHYS-AO-PH ] Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]Rotation vibrationCurve fittingbusinessInfraredGroup theorySoftware
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Computational Study of the Effect of Glyoxal–Sulfate Clustering on the Henry’s Law Coefficient of Glyoxal

2014

We have used quantum chemical methods to investigate the molecular mechanism behind the recently reported ( Kampf , C. J. ; Environ. Sci. Technol . 2013 , 47 , 4236 - 4244 ) strong dependence of the Henry's law coefficient of glyoxal (C2O2H2) on the sulfate concentration of the aqueous phase. Although the glyoxal molecule interacts only weakly with sulfate, its hydrated forms (C2O3H4 and C2O4H6) form strong complexes with sulfate, displacing water molecules from the solvation shell and increasing the uptake of glyoxal into sulfate-containing aqueous solutions, including sulfate-containing aerosol particles. This promotes the participation of glyoxal in reactions leading to secondary organic…

010504 meteorology & atmospheric sciences010501 environmental sciences01 natural scienceschemistry.chemical_compoundComputational chemistryPressureMoleculeOrganic chemistryComputer SimulationPhysical and Theoretical ChemistrySulfateEquilibrium constant0105 earth and related environmental sciencesAerosolsAqueous solutionAtmosphereSulfatesAqueous two-phase systemWaterGlyoxalHenry's lawSolvation shellModels ChemicalchemistrySolventsGlyoxalThe Journal of Physical Chemistry A
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Intercomparison of Soil Moisture Retrieved from GNSS-R and from Passive L-Band Radiometry at the Valencia Anchor Station

2019

In this paper, the SOMOSTA (Soil Moisture Monitoring Station) experiment on the intercomparison of soil moisture monitoring from Global Navigation Satellite System Reflectometry (GNSS-R) signals and passive L-band microwave radiometer observations at the Valencia Anchor Station is introduced. The GNSS-R instrument has an up-looking antenna for receiving direct signals from satellites, and a dual-pol down-looking antenna for receiving LHCP (left-hand circular polarization) and RHCP (right-hand circular polarization) reflected signals from the soil surface. Data were collected from the three different antennas through the two channels of Oceanpal GNSS-R receiver and, in addition, calibration …

010504 meteorology & atmospheric sciences0211 other engineering and technologies02 engineering and technologyELBARA-II radiometerlcsh:Chemical technology01 natural sciencesBiochemistryArticleAnalytical Chemistrylcsh:TP1-1185L-band radiometryElectrical and Electronic EngineeringOceanpalReflectometryInstrumentationWater content021101 geological & geomatics engineering0105 earth and related environmental sciencesRemote sensingValencia Anchor StationRadiometerMoistureGNSS-RMicrowave radiometerAtomic and Molecular Physics and OpticsGNSS applicationsSoil waterEnvironmental scienceRadiometrysoil moistureSensors
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