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*  Energy Dispersive X-ray Spectroscopy Pdf Download grusskarten.de haeufigsten zeichentrick zehnfingersystem « Bookidoc Search...
Keywords . X-ray spectroscopy, energy-dispersive X-ray .Energy Dispersive X-ray spectroscopy . analysis.com/download/449/ ... Energy dispersive x-ray absorption spectroscopy for studies of catalysts in . Energy dispersive x-ray absorption .Energy- ... Energy dispersive X-ray spectroscopy (EDS) Wavelength dispersive X-ray spectroscopy (WDS) 1thickness analysis of thin films by ... 1, J.X-Ray Energy Dispersive Spectroscopy In the Electron Microscope . Detection Efficiency Depends upon X-ray Energy. .X-ray ...
  http://arlelums.fileswill.com/2017/11/25/energy-dispersive-x-ray-spectroscopy-pdf-download-grusskarten-de-haeufigsten-zeichentrick-zehnfingersystem/
*  Phase transition kinetics of LiNi0.5Mn1.5O4 electrodes studied by in situ X-ray absorption near-edge structure and X-ray...
In situ time-resolved X-ray absorption near-edge structure (XANES) and X-ray diffraction (XRD) measurements are applied to track the phase transition processes of LixNi0.5Mn1.5O4, which is one of the most promising positive electrode materials for lithium ion batteries with its high redox potential
  http://pubs.rsc.org/en/Content/ArticleLanding/2013/TA/c3ta11637a
*  Nitrogen K-edge X-ray absorption near edge structure (XANES) spectra of purine-containing nucleotides in aqueous solution ...
The N K-edge X-ray absorption near edge structure (XANES) spectra of the purine-containing nucleotide, guanosine 5{sup ′}-monophosphate (GMP), in aqueous solution are measured under various pH conditions. The spectra show characteristic peaks, which originate from resonant excitations of N 1s electrons to π* orbitals inside the guanine moiety of GMP. The relative intensities of these peaks depend on the pH values of the solution. The pH dependence is explained by the core-level shift of N atoms at specific sites caused by protonation and deprotonation. The experimental spectra are compared with theoretical spectra calculated by using density functional theory for GMP and the other purine-containing nucleotides, adenosine 5{sup ′}-monophosphate, and adenosine 5{sup ′}-triphosphate. The N K-edge XANES spectra for all of these nucleotides are classified by the numbers of N atoms with particular chemical bonding characteristics in the purine moiety. ...
  https://www.osti.gov/scitech/biblio/22420009-nitrogen-edge-ray-absorption-near-edge-structure-xanes-spectra-purine-containing-nucleotides-aqueous-solution
*  2016-2017
Heptacene was generated by surface-assisted didecarbonylation of an α-diketone precursor on a Ag(111) surface. Monitoring of the surface reaction and characterization of the adsorbed heptacene was performed with scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), near-edge X-ray absorption fine structure (NEXAFS) spectroscopy, and density functional theory (DFT) calculations. The surface-assisted formation of heptacene occurs around 460 K. Both the heptacene and the precursor molecules are oriented along the high-symmetry directions of the (111) surface and their molecular π systems face towards the substrate. The interaction with the Ag(111) substrate is not laterally uniform, but appears to be strongest on the central part of the molecule, in line with the expectations from Clar's rule. In the STM images, heptacene shows a dumbbell shape, which may correspond to the substantial out-of-plane ...
  http://www.physik.uni-kiel.de/en/institutes/ag-berndt/publications/2016
*  Weakened CO adsorption and enhanced structural integrity of a stabilized Pt skin/PtCo hydrogen oxidation catalyst analysed by...
In situ X-ray absorption spectroscopy has afforded detailed structural and electronic characterization of a newly developed stabilized Pt-skin/PtCo alloy nanoparticle catalyst for CO-tolerant H2 oxidation. The X-ray absorption near-edge structure (XANES) results show the significant effects of H and CO adsorption o
  http://pubs.rsc.org/en/content/articlelanding/2017/cy/c7cy01700f/unauth
*  Sulfur and iron accumulation in three marine-archaeological shipwrecks in the Baltic Sea : The Ghost, the Crown and the Sword
Sulfur and iron concentrations in wood from three 17th century shipwrecks in the Baltic Sea, the Ghost wreck, the Crown and the Sword, were obtained by X-ray fluorescence (XRF) scanning. In near anaerobic environments symbiotic microorganisms degrade waterlogged wood, reduce sulfate and promote accumulation of low-valent sulfur compounds, as previously found for the famous wrecks of the Vasa and Mary Rose. Sulfur K-edge X-ray absorption near-edge structure (XANES) analyses of Ghost wreck wood show that organic thiols and disulfides dominate, together with elemental sulfur probably generated by sulfur-oxidizing Beggiatoa bacteria. Iron sulfides were not detected, consistent with the relatively low iron concentration in the wood. In a museum climate with high atmospheric humidity oxidation processes, especially of iron sulfides formed in the presence of corroding iron, may induce post-conservation wood degradation. Subject to more general confirmation by ...
  http://su.diva-portal.org/smash/record.jsf?pid=diva2:709883
*  Effects of soil composition and mineralogy on the bioaccessibility of arsenic from tailings and soil in gold mine districts of...
Bioaccessibility tests and mineralogical analyses were performed on arsenic-contaminated tailings and soils from gold mine districts of Nova Scotia, Canada, to examine the links between soil composition, mineralogy, and arsenic bioaccessibility. Arsenic bioaccessibility ranges from 0.1% to 49%. A weak correlation was observed between total and bioaccessible arsenic concentrations, and the arsenic bioaccessibility was not correlated with other elements. Bulk X-ray absorption near-edge structure analysis shows arsenic in these near-surface samples is mainly in the pentavalent form, indicating that most of the arsenopyrite (As1−) originally present in the tailings and soils has been oxidized during weathering reactions. Detailed mineralogical analyses of individual samples have identified up to seven arsenic species, the relative proportions of which appear to affect arsenic bioaccessibility. The highest arsenic bioaccessibility (up to 49%) is associated with ...
  http://nora.nerc.ac.uk/id/eprint/9835/
*  Local Structure and Surface Properties of CoxZn1−xO Thin Films for Ozone Gas Sensing
SEE PDF Full Length Article Writers: Ariadne C. Catto, Luís F. da Silva, Maria Inês B. Bernardi, Sandrine Bernardini, Khalifa Aguir, Elson Longo, and Valmor R. Mastelaro. Keywords: cobalt; gas sensor; ozone; XANES spectroscopy; XPS; zinc oxide. Abstract: A detailed study of the structural, surface, and gas-sensing properties of nanostructured CoxZn1-xO films is presented. X-ray diffraction (XRD) analysis revealed a decrease in the crystallization degree with increasing Co content. The X-ray absorption near-edge structure (XANES) and X-ray photoelectron spectroscopies (XPS) revealed that the Co2+ ions preferentially occupied the Zn2+ sites and that the oxygen vacancy concentration increased as the amount of cobalt increased. Electrical measurements showed that the Co dopants not only enhanced the sensor response at low ozone levels (ca. 42 ppb) but also led to a decrease in the operating temperature and ...
  http://cdmf.org.br/2016/09/09/local-structure-and-surface-properties-of-coxzn1%E2%88%92xo-thin-films-for-ozone-gas-sensing/
*  2017 August | SYK Pathway
Fujisawa et al. studied the electronic structures of CuFeS2 and CuAl0.9Fe0.1S2 by observing the phenomenon and analyzing the data of the states of Fe and Cu, and the valence-band of unit cell. The S 3p-Fe 3d bonding is found covalent base on the obvious tail of DAPT the XPS spectra of Cu 2p and S 2p [43]. Mikhlin et al. compared and analyzed the abraded chalcopyrite. and bornite in a vacuum chamber by X-ray absorption near-edge structure (XALES) to exam the electronic structure [44]. The result showed the Cu L3-edge had a strong pre-edge peak and a small post-edge peak, the Fe L2,3-edge energy was consistent with the Fe2+ oxidation state and S L-edge spectra was clearly observed [44]. It is widely accepted that the Neel temperature of CuFeS2 is extremely high, at 823 K [45] and [46]. Edelbro et al. proposed that the energy bands (−13.8 to 12.5 eV), which is lower than Fermi level, selleck chemical is similar to that of sphalerite. Woolley et al. demonstrated that, at ...
  http://sykpathway.com/2017/08/
*  Uranium Immobilization and Nanofilm Formation on Magnesium-Rich Minerals | Research Explorer | The University of Manchester
Polarization-dependent grazing incidence X-ray Absorption Spectroscopy (XAS) measurements were completed on oriented single crystals of magnesite [MgCO3] and brucite [Mg(OH)2] reacted with aqueous uranyl chloride above and below the solubility boundaries of schoepite (500, 50, and 5 ppm) at pH 8.3 and at ambient (PCO2 = 10-3.5) or reduced partial pressures of carbon dioxide (PCO2 = 10-4.5). X-ray Absorption Near Edge Structure (XANES) spectra show a striking polarization dependence ( = 0° and  = 90° relative to the polarization plane of the incident beam) and consistently demonstrated that the uranyl molecule was preferentially oriented with its Oaxial=U(VI)=Oaxial linkage at high angles (60-80º) to both magnesite () and brucite (0001). Extended X-ray Absorption Fine Structure (EXAFS) analysis shows that the "effective" number of U(VI) axial oxygens is the most strongly ...
  https://www.research.manchester.ac.uk/portal/en/publications/uranium-immobilization-and-nanofilm-formation-on-magnesiumrich-minerals
*  Solid-State NMR Literature Blog: Inorg. Chem. Vol. 48, Iss. 9
Cadmium(II) cysteinate compounds have recently been recognized to provide an environmentally friendly route for the production of CdS nanoparticles, used in semiconductors. In this article, we have studied the coordination for two cadmium(II) cysteinates, Cd(HCys)2·H2O (1) and {Cd(HCys)2·H2O}2·H3O+ClO4− (2), by means of vibrational (Raman and IR absorption), solid-state NMR (113Cd and 13C), and Cd K- and L3-edge X-ray absorption spectroscopy. Indistinguishable Cd K-edge extended X-ray absorption fine structure (EXAFS) and Cd L3-edge X-ray absorption near edge structure (XANES) spectra were obtained for the two compounds, showing similar local structure around the cadmium(II) ions. The vibrational spectra show that the cysteine amine group is protonated (NH3+) and not involved in bonding. The 113Cd solid-state cross-polarization magic angle spinning NMR spectra showed a broad ...
  http://ssnmr.blogspot.com/2009/05/inorg-chem-vol-48-iss-9.html
*  Water oxidation by simple manganese salts in the presence of cerium(iv) ammonium nitrate: towards a complete picture - Dalton...
For the first time, using scanning electron microscopy, transmission electron microscopy, X-ray absorption near edge structure and extended X-ray absorption fine structure X-ray diffraction, it is showed that MnCO3, MnWO4, Mn3(PO4)2·3H2O, MnS and Mn(VO3)2·xH2O under the water-oxidation conditions and in the presenc
  http://pubs.rsc.org/en/content/articlelanding/2018/dt/c7dt04143h
*  Group News
2010.12.13 The reseach article" Noradrenaline and a Thiol Analogue on Gold Surfaces: an IRAS, XPS and NEXAFS Study. " was published in Journal of Physical Chemistry C. Self-assembled monolayers and multilayers of a noradrenaline analogue (Nor-Pt) on gold substrates as well as multilayers of noradrenaline have been investigated by means of the molecular orientation, the molecule−surface interaction, the molecular composition and the functional group availability for further biointeraction processes, using X-ray photoelectron spectroscopy (XPS), infrared reflection−absorption spectroscopy (IRAS), and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy ...
  http://www.ifm.liu.se/applphys/surfnano/News/
*  Electronic structure of platinum complex/Zn-porphyrinato assembled macrosystems, related precursors and model molecules, as...
Macromolecular arrays containing Zn-diethynylporphyrin coordinated to platinum tethers were studied using near-edge X-ray absorption fine structure (NEXAFS) spectroscopy at the N K-edge. Porphin (Pf), 2,8,12,18-tetraethyl-5,15-diethynyl-3,7,13,17-tetramethylporphyrin (PfNH) and 2,8,12,18-tetraethyl-5,15-diethynyl-3,7,13,17-tetramethylporphyrinatozinc(II) (Zn-Pf2), have been taken as experimental models. The resonances assignment is supported by static-exchange (STEX) calculations for the porphin (Pf) and Zn-porphin (Zn-Pf1) molecules. By calculation, four pi* resonances occur for porphin (Pf) and two for Zn-Pf1. Experimentally we detect four resonances for porphin and PfNH, and two for the Zn-complexed ones. They can be assigned to core excitations to a couple of energy split pi* orbitals for each not equivalent N atom. Our calculations justify the observed low pi* intensity as due to an extended delocalization of the pi* orbitals. The ...
  https://iris.uniroma3.it/handle/11590/143389
*  Electronic Structure of Nitrogen-Doped Graphene in the Ground and Core-Excited States from First-Principles Simulations
We have calculated the N 1s near-edge X-ray absorption fine structure (NEXAFS) spectra of nitrogen-doped monolayer graphene (NG) using density functional theory (DFT) with the equivalent core hole approximation. The hexavacancy (6V) defect and its dependence on the nitrogen-doping concentration have been analyzed in detail via both N 1s -, pi* and N 1s -, sigma* transitions. The NEXAFS spectra are sensitive to the doping concentration of N in the pi* region: diluted doping weakens the main pi* peak and smears the oscillations in this region. The vacancy defect leads to a red-shift in both the pi and sigma spectra. A pyridinic nitrogen at the 6V defect center exhibits a sharp pi* peak at 398.4 eV, which agrees well with the experimental pre-edge structure at 398.6 eV. The sigma* peak is split in two, which can serve as the fingerprint to reveal the nature of the defect. A structural change from pyridinic to pyrrolic NG results in a distinctive difference in the spectral ...
  http://kth.diva-portal.org/smash/record.jsf?pid=diva2:849978
*  p|194|/p||p|The versatility of "Click" reactions: Molecular recognition at interfaces|/p| • Schalley Group • Department of...
In order to investigate molecular recognition on surfaces, an azide-functionalized monolayer was deposited on gold. The monolayer was characterized by x-ray photoelectron spectroscopy (XPS) and angle-resolved near-edge X-ray absorption fine structure (NEXAFS) experiments and the decomposition of the azide upon irradiation with X-ray beams was investigated. Subsequently, various alkyne-functionalized host and guest molecules were attached to the azide by 1,3-dipolar cycloaddition. These modified surfaces and their host/guest chemistry was analysed as well by XPS and angle-resolved NEXAFS. The reversibility of guest binding was shown for one example as a proof of principle. ...
  http://www.bcp.fu-berlin.de/en/chemie/chemie/forschung/OrgChem/schalley/Publications/Pub194/index.html
*  中国科学院高能物理研究所机构知识库(IHEP OpenIR): Phytotoxicity, Translocation, and Biotransformation of NaYF4 Upconversion Nanoparticles in a...
The increasing uses of rare-earth-doped upconversion nanoparticles (UCNPs) have obviously caused many concerns about their potential toxicology on live organisms. In addition, the UCNPs can be released into the environment, then transported into edible crop plants, and finally entered into food chain. Here, the soybean is chosen as a model plant to study the subchronic phytotoxicity, translocation, and biotransformation of NaYF4 UCNPs. The incubation with UCNPs at a relative low concentration of 10 mu g mL(-1) leads to growth promotion for the roots and stems, while concentration exceeding 50 mu g mL(-1) brings concentration-dependent inhibition. Upconversion luminescence imaging and scanning electron microscope characterization show that the UCNPs can be absorbed by roots and parts of the adsorbed UCNPs are then transported through vessels to stems and leaves. The near-edge X-ray absorption fine structure spectra reveal that the adsorbed NaYF4 nanoparticles are relatively ...
  http://ir.ihep.ac.cn/handle/311005/228782
*  The Electronic Properties and L3 XANES of Au and Nano-Au
The electronic properties of Au crystal and nano Au have been investigated by theory and experiment. Molecularly capped nano-Au was synthesized using the two-phase method. Au nano-particles have been characterized by X-Ray Diffraction (XRD) and Transmission Electron Microscopy (TEM). They retain the fcc crystal structure. Their sizes have been determined to be in a range from 5.5 nm to 1.7 nm. The L3 X-ray Absorption Near Edge Structure (XANES) of nano-Au and Au foil have been recorded using synchrotron radiation, and examined by theoretical calculation [1] based on the first principles [2,3]. Both theory and experiment show that the nano-Au particles have essentially all the Au L3 XANES features of bulk Au in the near edge region with less pronounced resonance peaks. It is also shown that nano Au exhibits lower 4f binding energy than bulk Au in good agreement with quantum confined Au systems reported previously [3,4].
  http://www.nsti.org/Nanotech2003/showabstract.html?absno=510
*  Structure and predicted near edge x-ray absorption fine structure spectra for the surface of liquid formamide from molecular...
A modification of an existing model for formamide interactions in the liquid phase makes it possible to study the bulk liquid and its free surface at conditions near the triple point, i.e., 300 K and essentially zero pressure, by (MD) molecular-dynamics simulation. Density profiles and orientation profiles in the surface region show the depth and gradual loss of the molecular ordering in the transition from bulk vapor to the bulk liquid. Near edge x-ray absorption fine structure (NEXAFS) resonance intensity spectra are computed from the orientation profiles, so that comparison should be possible with experimental depth resolved NEXAFS spectra.. ...
  http://kth.diva-portal.org/smash/record.jsf?pid=diva2:338664
*  X-ray absorption spectroscopy (XAS) - Online Dictionary of Crystallography
X-ray absorption spectroscopy (XAS) is a technique for measuring the linear absorption coefficient µ(E) of a substance as a function of the incident photon energy E in the X-ray regime. This technique is element and orbital-specific and determines the local atomic and electronic structure of matter. XAS conventionally includes techniques of XAFS, which in turn includes both XANES and EXAFS. An XAS spectrum may also be obtained using fluorescence, electron yield and scattering processes indirectly (i.e. without directly measuring the absorption of X-rays). ...
  http://reference.iucr.org/dictionary/X-ray_absorption_spectroscopy_
*  Electric-field-control of magnetic remanence of NiFe2O4 thin film epitaxially grown on Pb(Mg1/3Nb2/3)O3â€"PbTiO3
We propose an asymmetric bilayer structure in which the magnetic remanence (MR) is controlled by the in-plane strain of the top NiFe2O4 (NFO) layer epitaxially constrained by the bottom Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) substrate. In this asymmetric structure, an electric-field-induced giant piezoelectric strain from the bottom PMN-PT layer is effectively transferred to the top NFO layer. We have shown that the room-temperature magnetic remanence (MR) of the 100-nm-thick NFO layer is enhanced by 46% when an electric-field-induced in-plane compressive strain is about -0.1%. Synchrotron x-ray absorption near edge structure study supports a scenario of the cation-charge redistribution between Ni2+ and Fe3+ ions under the condition of an electric-field-induced in-plane compressive strain ...
  http://connection.ebscohost.com/c/articles/50510792/electric-field-control-magnetic-remanence-nife2o4-thin-film-epitaxially-grown-pb-mg1-3nb2-3-o3-pbtio3
*  Most recent papers with the keyword High Resolution | Read by QxMD
The effect of introducing porosity and the insertion of methyl groups in SiO4 tetrahedra on the distribution of valence and conduction band states of SiO2 was studied using high-resolution near edge X-ray absorption fine structure spectroscopy (NEXAFS) and soft X-ray photoelectron spectroscopy (XPS). Alignment of NEXAFS spectra and valence band XPS spectra in a common energy scale was performed using binding energies of the initial levels obtained by XPS. It was established that the insertion of methyl groups into SiO4 tetrahedra leads to a significant shift of the top of the valence band EV to smaller binding energies due to the reduction of the electronegativity of the nearest surrounding neighbors of the Si atoms, while introducing porosity changes the position of EV only slightly ...
  https://www.readbyqxmd.com/keyword/111578
*  An X-ray diffraction and X-ray absorption spectroscopy joint study of neuroglobin | IRIS Università degli Studi dell'Aquila
Neuroglobin (Ngb) is a member of the globin family expressed in the vertebrate brain, involved in neuroprotection. A combined approach of X-ray diffraction (XRD) on single crystal and X-ray absorption spectroscopy (XAS) in solution, allows to determine the oxidation state and the structure of the Fe-heme both in the bis-histidine and the CO-bound (NgbCO) states. The overall data demonstrate that under Xray the iron is photoreduced fairly rapidly, and that the previously reported X-ray structure of ferric Ngb [B. Vallone, K. Nienhaus, M. Brunori, G.U. Nienhaus, Proteins 56 (2004) 85-92] very likely refers to a photoreduced species indistinguishable from the dithionite reduced protein. Results from the XAS analysis of NgbCO in solution are in good agreement with XRD data on the crystal. However prolonged X-ray exposure at 15 K determines CO release. This preliminary result ...
  https://ricerca.univaq.it/handle/11697/6590
*  Graphene Literature Reviews: Defect formation in graphene nanosheets by acid treatment: an x-ray absorption spectroscopy and...
The authors claim (or imply) that this structure will be an adequate analog for actual graphene sheets, and proceed to treat it with HCl for a few hours. They then did the same treatment on another sample using distilled water instead of HCl and took some SEM images to make sure they still had carbon nanosheets. The authors moved on to analyze the sheets with X-ray absorption spectroscopy (XAS, pdf summary from the University of Calgary here) which, in analogy to XPS, gives information on what kind of bonds are present in the sample (pi* C-C, sigma* C-O, pi* C=O, etc.). The authors find that, compared to a control, their acid-treated samples have a significantly higher peak that they ascribe to C-O bonds and a lower peak in the area attributed to C-C pi* and sigma* bonds. They theorize that the acid broke C-C bonds, which were replaced by hydroxyl groups, and back this up by mentioning the higher wettability (read: lower hydrophobicity) of the film and by ...
  http://graphenelitreviews.blogspot.com/2008/04/defect-formation-in-graphene-nanosheets.html
*  Patent US5408481 - Intracavity sum frequency generation using a tunable laser containing an ... - Google Patents
A means for intracavity sum frequency generation is described in which a er operates simultaneously, cw, at two wavelengths where the net gain at one wavelength is substantially lower than that at the other. The optical alignment of the resonator provides a region where both fundamental wavelengths are overlapped, and another region where both feedback paths are spatially distinct. An active feedback mirror is located in the path of the lower net gain laser transition to provide optical amplification at that wavelength. The laser resonator further contains a sum frequency generating crystal for intracavity sum frequency generation of the two fundamental wavelengths. The sum frequency generating crystal is placed near a laser resonator cavity mode waist in the region where both wavelengths are spatially superimposed, producing the sum frequency of the two wavelengths. An intracavity polarization rotator provides the appropriate orientation of the polarization of the two fundamental wavelengths in the
  http://www.google.com/patents/US5408481?dq=6,970,917
*  "Chemistry, testing and management of phosphorus and zinc in calcareous" by Dustin L. Harrell
Calcareous soils make up some of the most productive agriculture lands in Louisiana. Due to their minimal occurrence little research has been done on these soils. Understanding phosphorus (P) chemistry is necessary for environmentally sound management of these soils. In this study, P speciation was investigated using several chemical fractionation procedures as well as x-ray absorption near-edge spectroscopy (XANES) coupled with principal component analysis (PCA) and least-squares linear combination fitting (LCF) on five calcareous Louisiana soils of different geological origins. Phosphorus sorption isotherm parameters were determined and their relationships with other properties were evaluated. In addition, Zinc (Zn) lability due to the interaction with P and other fertilizer nutrients was characterized and a fertilizer P and Zn response trial for corn on a calcareous Norwood silt loam soil was conducted. The results showed that these ...
  http://digitalcommons.lsu.edu/gradschool_dissertations/1971/