Search results for "TRIP"

showing 10 items of 2134 documents

Über makrozwitterionen, 9. Über den mechanismus der anionischen polymerisation von acrylnitril mit tertiären phosphinen unter Zusatz von LiCl

1974

Die anionische Polymerisation von Acrylnitril mit tertiaren Phosphinen in Dimethylformamid bei 25°C wurde unter Zusatz von LiCl untersucht. Es zeigte sich, das durch den Salzzusatz mit Triphenylphosphin als Initiator eine Polymerisation uber Makrozwitterionen ermoglicht wird und mit Triathylphosphin die (auch ohne Salzzusatz schon mogliche) Makrozwitterionenbildung starker auftritt. The effect of LiCl on the polymerization of acrylonitrile initiated by tertiary phosphines at 25 C in dimethylformamide was studied. Macrozwitterions are formed only in the presence of the added salt when triphenylphosphine is used as an initiator. In the system initiated by triethylphosphine formation of macroz…

chemistry.chemical_classificationchemistry.chemical_compoundchemistryPolymerizationPolymer chemistryDimethylformamideSalt (chemistry)AcrylonitrileTriphenylphosphineDie Makromolekulare Chemie
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Polyunsaturated fatty acids and Plasmalogens in diabetics

2012

Purpose Plasmalogens (PLS) are phospholipids characterized by a vinyl ether bond and a preferential esterification of polyunsaturated fatty acids (PUFA). We have previously shown that the lack of PLS leads to retinal hyper-capillarization. We hypothesize that PLS are negative regulators of vascular development, and aimed to check their circulating levels in diabetic patients. Methods Blood samples were collected from 88 patients and 14 control subjects. Among diabetics we had 14 patients without diabetic retinopathy (DR), 12 with a mild non proliferative DR, 12 with a moderate non proliferative DR, 22 with a severe non proliferative DR and 24 with a proliferative DR (PDR). Erythrocytes were…

chemistry.chemical_classificationmedicine.medical_specialtyChemistryRetinalGeneral MedicineDiabetic retinopathymedicine.diseasePathogenesisOphthalmologychemistry.chemical_compoundEndocrinologyBiochemistryDocosahexaenoic acidInternal medicineTriple quadrupole mass spectrometrymedicinelipids (amino acids peptides and proteins)Arachidonic acidGas chromatographyPolyunsaturated fatty acidActa Ophthalmologica
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ChemInform Abstract: New Ionic Liquid-Modified Silica Gels as Recyclable Materials for L-Proline- or H-Pro-Pro-Asp-NH2-Catalyzed Aldol Reaction.

2008

L-proline and the tripeptide H–Pro–Pro–Asp–NH2 (1) have been supported, by adsorption, onto the surface of modified silica gels functionalized with a monolayer of covalently attached 1,2-dimethyl-imidazolium chloride, tetrafluoroborate or hexafluorophosphate ionic moieties, respectively. Three different linkers were used to attach the ionic liquid moiety to the surface of these supports. The resulting materials have been used as catalysts for the aldol reaction between acetone and several substituted benzaldehydes. Good yields and enantioselectivities, comparable to or better than those obtained under homogeneous conditions, were obtained. These materials are easily recovered by filtration,…

chemistry.chemical_compoundAddition reactionAdsorptionchemistryAldol reactionHexafluorophosphateIonic liquidPolymer chemistryMoietyIonic bondingGeneral MedicineTripeptideChemInform
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ChemInform Abstract: Multifunctionality in Hybrid Magnetic Materials Based on Bimetallic Oxalate Complexes

2011

This tutorial review illustrates the design of multifunctional oxalate-based magnetic materials through the combination of the intrinsic magnetism of the metal–organic framework and the additional properties introduced by several organic/inorganic functional cations.

chemistry.chemical_compoundChemical engineeringChemistryMagnetismGeneral Medicineequipment and supplieshuman activitiesBimetallic stripOxalateChemInform
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Synthesis of azamacrocycles via a Mitsunobu reaction

2005

Reaction of pernosylated diethylenetriamine and 2-substituted propane-1,3-diols in dry THF in the presence of triphenylphosphine and diisopropyl azodicarboxylate gives the corresponding protected 9-substituted 1,4,7-triazacyclodecanes. The Mitsunobu reaction was also used in the preparation of 3-substituted 1,5,9-triazacyclododecanes and macrocyclic pyridine derivatives.

chemistry.chemical_compoundChemistryDiisopropyl azodicarboxylateOrganic ChemistryDrug DiscoveryPyridineDiethylenetriamineOrganic chemistryMitsunobu reactionTriphenylphosphineBiochemistryTetrahedron Letters
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Feinstrukturanalyse eines diskotischen Polymers durch Elektronenbeugung und hochauflösende Elektronenmikroskopie

1989

chemistry.chemical_compoundCrystallographyChemistrylawLiquid crystalTriphenyleneGeneral MedicineElectron microscopelaw.inventionAngewandte Chemie
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Cover Picture: Insertion of a Single-Molecule Magnet inside a Ferromagnetic Lattice Based on a 3D Bimetallic Oxalate Network: Towards Molecular Analo…

2014

chemistry.chemical_compoundCrystallographyFerromagnetismChemistryMagnetLattice (order)Organic ChemistryX-ray crystallographySingle-molecule magnetGeneral ChemistryBimetallic stripCatalysisOxalateChemistry - A European Journal
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Quantum Chemistry of Excited States in Polyhedral Boranes

2015

In this Chapter we describe the electronic structure of ground states and excited states of the two isomers of octadecaborane (22), anti- and syn-B18H22, and the new derivative of anti-B18H22, the polyhedral substituted borane 4,4′-(HS)2-anti-B18H20. A theoretical interpretation is given on the fluorescence of the anti-B18H22 isomer, and the non-radiative decay of the syn-B18H22 isomer, an unsolved problem since 1962. For the new derivative of anti-B18H22, substitution of hydrogen atoms in positions 4 and 4′ by SH groups allows the tuning of the photophysical properties in 4,4′-(HS)2-anti-B18H20, facilitating intersystem crossing from the excited singlet state to the triplet state.

chemistry.chemical_compoundIntersystem crossingchemistryComputational chemistryExcited stateBoranesOctadecaboraneElectronic structureConical intersectionTriplet stateBoraneMolecular physics
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Singlet oxygen generation in PUVA therapy studied using electronic structure calculations

2009

Abstract The ability of furocoumarins to participate in the PUVA (Psoralen + UV-A) therapy against skin disorders and some types of cancer, is analyzed on quantum chemical grounds. The efficiency of the process relies on its capability to populate its lowest triplet excited state, and then either form adducts with thymine which interfere DNA replication or transfer its energy, generating singlet molecular oxygen damaging the cell membrane in photoactivated tissues. By determining the spin–orbit couplings, shown to be the key property, in the intersystem crossing yielding the triplet state of the furocoumarin, the electronic couplings in the triplet–triplet energy transfer process producing …

chemistry.chemical_compoundIntersystem crossingchemistrySinglet oxygenFurocoumarinExcited stateSinglet fissionGeneral Physics and AstronomyElectronic structurePhysical and Theoretical ChemistryTriplet statePhotochemistryThymineChemical Physics
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Selenophene-Based Hole-Transporting Materials for Perovskite Solar Cells

2021

Two novel and simple donor-π-bridge-donor (D-π-D) hole-transporting materials (HTMs) containing two units of the p-methoxytriphenylamine (TPA) electron donor group covalently bridged by means of the 3,4-dimethoxyselenophene spacer through single and triple bonds are reported. The optoelectronic and thermal properties of the new selenium-containing HTMs have been determined using standard experimental techniques and theoretical density functional theory (DFT) calculations. The selenium-based HTMs have been incorporated in mesoporous perovskite solar cells (PSCs) in combination with the triple-cation perovskite [(FAPbI3 )0.87 (MAPbBr3 )0.13 ]0.92 [CsPbI3 ]0.08 . Limited values of power conver…

chemistry.chemical_compoundMaterials sciencechemistryCovalent bondPhotovoltaic systemThermalPhysical chemistryDensity functional theoryElectron donorGeneral ChemistryMesoporous materialTriple bondPerovskite (structure)
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