Search results for "X-Ray"

showing 10 items of 4234 documents

Erratum: “Nanoscale x-ray imaging of spin dynamics in yttrium iron garnet” [J. Appl. Phys. 126, 173909 (2019)]

2021

chemistry.chemical_compoundMaterials scienceCondensed matter physicschemistrySpin dynamicsX-rayYttrium iron garnetGeneral Physics and Astronomyddc:530Nanoscopic scaleJournal of Applied Physics
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Magnetic moment investigations of epitaxial magnetite thin films

2008

In this report, we provide an x-ray magnetic circular dichroism (XMCD) study for 100nm thick epitaxial magnetite (Fe3O4) films on MgO (001) and Al2O3 (0001) substrates. For XMCD, we recorded the surface sensitive total electron yield and the bulk sensitive transmission spectra. From the analysis of the XMCD data, we find an increased Fe spin moment (10% larger) at the surface of the film on MgO (100) with respect to the corresponding bulk value of the film. Surface and bulk spin moments of the film on Al2O3(0001) are almost equal. For both films, the bulk orbital to spin moments ratio increases from zero at 70K to 0.03–0.04 at 300K. For Fe3O4∕MgO (001), the surface orbital to spin moment ra…

chemistry.chemical_compoundMaterials scienceFerromagnetismchemistryX-ray magnetic circular dichroismMagnetic momentSpin polarizationCondensed matter physicsMagnetic circular dichroismGeneral Physics and AstronomyThin filmSpin (physics)MagnetiteJournal of Applied Physics
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Surfactant controlled preparation of mesostructured transition-metal oxide compounds

1994

The use of surfactants as templates allows the synthesis of mesostructured transition-metal oxides by a cooperative, interface controlled condensation process.

chemistry.chemical_compoundTemplatePulmonary surfactantTransition metalChemical engineeringStereochemistryChemistryTransmission electron microscopyCondensation processX-ray crystallographyOxideMolecular MedicineJ. Chem. Soc., Chem. Commun.
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Darstellung, Kristallstruktur und Wirkung von 2-Methyl-3-(4-oxo-3-phenyl-thiazolidin-2-ylidenamino)-4-(3H)-chinazolinon

1984

Quinazolinones. 1. Preparation, crystal structure and action of 2-methyl-3-(4-oxo-3-phenyl-thiazolidine-2-ylidenamino)-4-(3H)- quinazolinone.

chemistry.chemical_compoundchemistryBicyclic moleculeStereochemistryDrug DiscoveryX-ray crystallographyLactamPharmaceutical ScienceMoleculeBiological activityCrystal structureQuinazolinoneArchiv der Pharmazie
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Synthesis and structural characterization of cis- and trans-fused 4a,5,6,7,8,8a-hexahydro-2H,4H-1,3-benzodithiines and their 2-methyl and 2,2-dimethy…

2002

Both cis- and trans-fused 4a,5,6,7,8,8a-hexahydro-2H,4H-1,3-benzodithiine together with their 2-methyl and 2,2-dimethyl derivatives were prepared as racemates from the appropriate dithiols obtained via multistep syntheses. The products were characterized by 1 H and 13 C NMR, mass spectrometry, and for two of the cis-fused compounds by X-ray diffraction. 1 H, 1 H vicinal coupling constants indicated that all compounds attain chair-chair conformations as their predominant conformations. All three trans-fused isomers exist in totally biased chair-chair conformations and are essentially conformationally locked, whereas the cis-fused compounds are conformationally mobile and can potentially atta…

chemistry.chemical_compoundchemistryBicyclic moleculeStereochemistryOrganic ChemistryX-ray crystallographyDithiolMoleculeCarbon-13 NMRChemical synthesisConformational isomerismCis–trans isomerismThe Journal of organic chemistry
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ChemInform Abstract: Selective Ipso-Nitration of tert-Butylcalix(4)arene 1,3-Diethers: X- Ray Structure of an Unexpected Side Product.

2010

chemistry.chemical_compoundchemistryNitrationSide productX-rayGeneral MedicineMedicinal chemistryChemInform
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Indoloquinolines, Indolobenzoxazines and Quinazolophthalazines Prepared from Norbornane/eneamino Acids and Hydrazides

2005

The reactions of di-endo- and di-exo-aminonorbornane/enecarboxylic acids 1–4 with ethyl 2-(2-oxocyclohexyl)acetate afforded methanoindoloquinolines 5, 6, 8, and 9, the oxo ester participating as a two-membered sp2 building block. In the cases of di-exo- and di-endo-aminonorbornenecarboxylic acids 2 and 4, methanoindolobenzoxazinediones 7 and 10 were also formed; compound 7 was also isolated from the mother liquor of 10. The reactions of ethyl 2-(2-oxocyclohexyl)acetate with aminonorbornane/enecarbohydrazides 11–14 result in the methanoquinazolophthalazines 15–18. The structures of the compounds were elucidated by NMR spectroscopy, and for 6, 7, 8, and 10 also by X-ray crystallography. (© Wi…

chemistry.chemical_compoundchemistryOrganic ChemistryX-ray crystallographyOrganic chemistryNuclear magnetic resonance spectroscopyMother liquorPhysical and Theoretical ChemistryNorbornaneBlock (periodic table)Medicinal chemistryEuropean Journal of Organic Chemistry
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Crystal Engineering Studies of the Complexes of Ethyl Resorcinarene with Aromatic Nitrogen Heterocycles

2003

Five X-ray structures of complexes of ethyl resorcinarene with aromatic nitrogen heterocycles (imidazole, 1,2,4-triazole, pyridine, pyrazine, 2-pyridylmethanol and quinoline) show that ethyl resorcinarene spontaneously forms molecular inclusion complexes with five- and six-membered aromatic nitrogen heterocycles via π π and CH π interactions. However, with 10-membered quinoline, no molecular inclusion complex is formed. Instead, quinoline manifests crystal lattice inclusion.

chemistry.chemical_compoundchemistryPyrazinePyridineQuinolineX-ray crystallographyImidazoleOrganic chemistryGeneral ChemistryCrystal structureResorcinareneCrystal engineeringMedicinal chemistrySupramolecular Chemistry
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Proximity Effect using a Nanocage Structure: Polyhedral Oligomeric Silsesquioxane-Imidazolium Tetrachloro- palladate Salt as a Precatalyst for the Su…

2016

A polyhedral oligomeric silsesquioxane-imidazolium tetrachloropalladate salt (POSS-Imi-PdCl4) was prepared by the reaction of a polyhedral oligomeric silsesquioxane-imidazolium chloride salt (POSS-Imi-Cl) with PdCl2 and used as a pre-catalyst for the Suzuki-Miyaura reaction in water at 100 °C at a low loading (0.08-0.16 mol %). Biphenyl compounds were isolated in high to excellent yields. A comparison of the POSS-based catalyst with the corresponding catalyst without the nanocage structure (i.e., 1-butyl-3-methylimidazolium tetrachloropalladate) highlighted the role of the POSS structure to reach higher yields in the Suzuki-Miyaura reaction. This result is ascribed to a proximity effect of …

chemistry.chemical_elementSalt (chemistry)supported catalyst010402 general chemistry01 natural sciencesCatalysisCatalysisInorganic Chemistrychemistry.chemical_compoundNanocagesX-ray photoelectron spectroscopyPolymer chemistryOrganic chemistrysupported catalystsPhysical and Theoretical Chemistrychemistry.chemical_classification010405 organic chemistryChemistryOrganic Chemistrypalladiumcage compoundSilsesquioxane0104 chemical sciencesBiphenyl compoundphase-transfer catalysiphase-transfer catalysisC-C couplingcage compoundsProximity effect (atomic physics)Palladium
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ElaC Encodes a Novel Binuclear Zinc Phosphodiesterase

2002

ElaC is a widespread gene found in eubacteria, archaebacteria, and mammals with a highly conserved sequence. Two human ElaC variants were recently associated with cancer (Tavtigian, S. V., Simard, J., Teng, D. H., Abtin, V., Baumgard, M., Beck, A., Camp, N. J., Carillo, A. R., Chen, Y., Dayananth, P., Desrochers, M., Dumont, M., Farnham, J. M., Frank, D., Frye, C., Ghaffari, S., Gupte, J. S., Hu, R., Iliev, D., Janecki, T., Kort, E. N., Laity, K. E., Leavitt, A., Leblanc, G., McArthur-Morrison, J., Pederson, A., Penn, B., Peterson, K. T., Reid, J. E., Richards, S., Schroeder, M., Smith, R., Snyder, S. C., Swedlund, B., Swensen, J., Thomas, A., Tranchant, M., Woodland, A. M., Labrie, F., Sko…

chemistry.chemical_elementZincBiologymedicine.disease_causeBiochemistrybeta-LactamasesHomology (biology)Conserved sequenceGene productEscherichia colimedicineHistidineCloning MolecularBinding siteMolecular BiologyEscherichia coliHistidineCell NucleusIonsBinding SitesModels StatisticalPhosphoric Diester HydrolasesSpectrum AnalysisX-RaysPhosphodiesteraseCell BiologyProtein Structure TertiaryOxygenKineticsZincBiochemistrychemistryChromatography GelProtonsDimerizationProtein BindingJournal of Biological Chemistry
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