X-ray spectroscopy codes were applied to achieve quantitative interpretation of x-ray absorption near edge structure
Energy Citations Database
The research presented elucidates the oxidation chemistry occurring in hydrogen peroxide bleached kraft pulp fibers by employing carbon near edge x-ray ... ...
NBII National Biological Information Infrastructure
near-edge x-ray absorption fine-structure (NEXAFS) spectroscopy, allows for quantitative determination of submicron polymer blend composition. At a lateral resolution of 50 nm,...
Science.gov Websites
... X-Ray absorption near edge spectroscopy (XANES); Co-K-edge EXAFS spectra were collected at the Stanford Synchrotron Radiation Laboratory ...
DTIC Science & Technology
One of the long term research goals has been to attain a quantitative theory of deep core X-ray spectroscopies. These spectroscopies include X-ray absorption fine structure (XAFS), X-ray absorption near edge structure (XANES), X-ray magnetic circular dich...
National Technical Information Service (NTIS)
Near-Edge X-ray Absorption Fine Structure Spectroscopy of MDI and TDI Polyurethane Polymers Stephen) to differences in key chemical components of polyurethane polymers is presented. Carbon 1s NEXAFS spectra of polyurethane polymers made from 4,4-methylene di-p-phenylene isocyanate (MDI) and toluene diisocyanate (TDI
E-print Network
Near edge x-ray absorption fine structure (NEXAFS) and infrared reflection-absorption spectroscopy (IRRAS) have been used to study the orientational behavior of thin films of poly(3-methylthiophene) electrochemically polymerized on a platinum surface. Cle...
The question of valence of Cu and rare-earth atoms in the newly discovered oxide superconductors with high transition temperatures is crucial to the understanding of their electronic structure. X-Ray Absorption Near Edge Structure and Moessbauer Spectrosc...
The L shell x-ray absorption near edge structure (XANES) for the 3d transition metals Ca-Cu is dominated by atomic-like behavior which is poorly understood. It has been studied by electron energy loss spectroscopy (EELS) and bremsstrahlung isochromat spec...
Sputter deposited non-stoichiometric tantalum nitride films are oxidized in air between 200 and 500{degrees}C to form a passive film. The oxidized films have been studied with x-ray absorption near edge spectroscopy (XANES) and extended x-ray absorption near ...
DOE Information Bridge
X-ray absorption spectroscopy is now being applied to the study of a wide range of surface structures. The usefulness of surface EXAFS (SEXAFS) is illustrated by reviewing measurements on the oxidation of aluminum, the absorption of Te and I on silicon an...
... Nevertheless, iron K-edge XANES is highly effective at identify- ing and quantifying ... 4.1.2.1 X-Ray Absorption near Edge Structure Spectroscopy ...
STXM and C-NEXAFS (carbon near edge absorption micro-spectroscopy) microanalysis were used to analysis the microchemistry of cokes and highly carbonaceous materials. The issue of molecular orientation is addressed by using the intrinsic polarization of th...
Diamondoids, hydrocarbon molecules with cubic-diamond-cage structures, have unique properties with potential value for nanotechnology. The availability and ability to selectively functionalize this special class of nanodiamond materials opens new possibil...
... Near edge X-ray absorption fine structure (NEXAFS) spectroscopy ... The X-ray beam was elliptically polarized ... which in- cludes the carbon K edge. ...
The following were studied: confinement of block copolymers, free surface confinement, effects of substrate interactions, random copolymers at homopolymer interfaces, phase separation in thin film polymer mixtures, buffing of polymer surfaces, and near edge x-ray absorption fine structure spectroscopy.
. Nucleic Acids Res. 23:3627�32 7. Peterlinz KA, Georgiadis RM, Herne TM, Tarlov MJ. 1997. J. Am. Chem. Soc
-ray absorption near edge structure (�XANES) spectroscopy. Zinc is predominantly incorporated in calcite, and cadmium in calcite and vaterite. Aragonite, which occurs occasionally, does not seem to contain trace metals. In addition to being precipitated in its three possible polymorphic forms, calcite, aragonite
more competitive for widespread implementation was obtained using near-edge x-ray absorption fine structure (NEXAFS) spectroscopy performed at ALS Beamline 8.0.1. The relevant...
We present C-, N-, and O-XANES (X-ray Absorption Near-Edge Spectroscopy) results of organic residues
NASA Technical Reports Server (NTRS)
The X-ray absorption near-edge spectroscopy (XANES) technique has been used to determine the chemical change of elements induced by bark diseases in Havea brasiliensis (rubber latex tree). The results show the good sensitivity of in situ XANES for characterizing the chemical structure of phosphorus, sulfur, potassium and calcium in ...
PubMed
A technique to suppress the core-hole lifetime broadening in near- edge x-ray spectroscopy is presented. A simple theoretical explanation based on total energy conservation in the fluorescence process is given to explain the improved resolution. The experimental arrangement is shown together with an application to the L[sub III] edge ...
A technique to suppress the core-hole lifetime broadening in near- edge x-ray spectroscopy is presented. A simple theoretical explanation based on total energy conservation in the fluorescence process is given to explain the improved resolution. The experimental arrangement is shown together with an application to the L{sub III} edge ...
We present a compact setup for near-edge x-ray absorption spectroscopy at the carbon K-edge based on a laser-driven plasma source. Thin polymer films were investigated, showing good agreement with corresponding synchrotron data. Furthermore we have examined the carbon near-edge structure of phospholipids and fulvic acids, providing ...
NASA Astrophysics Data System (ADS)
Brush-like ZnO/TiO2 core-shell nanostructures have been prepared by a two-step route combined with hydrothermal method and magnetron sputter. Electronic properties of these interesting nanostructures were investigated by both photoelectron spectroscopy and X-ray absorption. Near edge X-ray ...
This review gives a brief description of the theory and application of X-ray absorption spectroscopy, both X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS), especially, pertaining to photosynthesis. The advantages and ...
Manganese model complexes, relevant to the oxygen-evolving complex (OEC) in photosynthesis, were studied with Mn K-edge X-ray absorption near-edge spectroscopy (XANES), Mn Kb X-ray emission spectroscopy (XES), and vibrational spectroscopy. A more detailed...
X-ray Photo Emission Electron Microscopy (X-PEEM) and Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy were applied to study the properties of amorphous hard carbon overcoats on disks and sliders, and the properties of the lubricant. The mo...
In this study, wheat leaves infected with brown rust, a plant disease of serious economic concern caused by the fungus Puccinia triticina, were investigated using spatially resolved XANES (X-ray Absorption Near Edge Structure) spectroscopy at the sulfur K-absorption edge.
Applications of x-ray absorption near-edge spectroscopy (XANES) and the design of cells for in situ corrosion studies are reviewed. Passive films studies require very thin metal or alloy layers be used having a thickness of the order of the films formed b...
of the DCM was calibrated relative hal-00261713,version1-8Mar2008 #12;15 to the Au K-edge of metallic gold-ray absorption near-edge spectroscopy) and EXAFS (extended x-ray absorption fine- structure) spectroscopy. Iterative transformation factor analysis of XANES and EXAFS spectra suggested ...
We demonstrate the feasibility of near edge x-ray absorption fine structure spectroscopy on solids by means of femtosecond soft x-ray pulses from a free-electron laser (FEL). Our experiments, carried out at the FEL at Hamburg used a special sample geometry, spectrographic energy dispersion, single shot ...
K-absorption edge of coordinated ions exhibits a fine structure (through the use of XANES, or x-ray absorption near edge structures) that reflects the electronic repartition and the chemical reactivity of these ions. Comparative analysis of iron K-absorption-edge shape for hemoglobin ...
PubMed Central
A program to investigate the x-ray absorption behavior of materials subjected to high pressures has been continued. Of particular interest has been the EXAFS (extended x-ray absorption fine structure) and XANES (x-ray absorption near edge structure). Mate...
We propose to develop a quantitative theory of x-ray spectroscopies in the near edge region, within about 100 eV of threshold. These spectroscopies include XAFS (X-ray absorption fine structure), photoelectron diffraction (PD), and diffraction anomalous fine structure (DAFS), all of which are ...
Sputter deposited non-stoichiometric tantalum nitride films are oxidized in air between 200 and 500(degrees)C to form a passive film. The oxidized films have been studied with x-ray absorption near edge spectroscopy (XANES) and extended x-ray absorption n...
(p-phenylene terephthalamide) (Kevlar), poly(ethylene terephthalate), poly(p-phenylene-1,3,4-oxadiazole), and 2,5-di. Samples of poly(p-phenylene terephthalamide) (Kevlar), poly- (ethylene terephthalate) (PET), poly-ray absorption spectra of AF51, Kevlar, PET, and PPOD for fingerprinting. The interpretation of the spectral
X-ray absorption fine spectra at the Al K-edge were measured experimentally on and calculated theoretically via the multiple-scattering formalism for a chemically pure and physically perfect synthetic (alpha)-Al(sub 2)O(sub 3) ((alpha)-alumina), a natural...
The nature of the core level reflected in x ray photoelectron spectroscopy, Auger electron spectrosocopy, and x ray absorption near edge structure is considered. An understanding of the effects of anion and cation electronegativity on spectra for the transition metal halides is obtained. This knowledge is applied ...
Orientation and charge transfer upon adsorption of thioethanol on copper surface at room temperature has been studied by near edge x-ray absorption fine structure (NEXAFS) and x-ray photoelectron spectroscopy (XPS) techniques. It is found that thioethanol adsorbs dissociatively on the Cu(111) surface. Polarization ...
X-ray absorption near-edge spectroscopy (XANES) has been applied to natural rubber in order to study the local environment of sulfur atoms in sulfur crosslinking structures introduced in the vulcanization process. Different types of chemical accelerators in conventional, semi-efficient and efficient vulcanization systems were ...
Soft X-ray absorption spectroscopy (XAS), using fluorescence yield, was used to study the boron K near edge in MgB2 superconductor. The sample consists of MgB2 crystallites randomly oriented in a magnesium matrix. Abrasion of the sample surface in vacuum provides a surface relatively free of boron-containing ...
We describe here a new, non-destructive method for valence determinations of vanadium and oxygen fugacity estimates for basaltic glasses with spatial resolution of a few micrometers using synchrotron x-ray absorption near edge structure (XANES) spectroscopy. A promising proxy for oxygen fugacity is the valence of ...
X-ray absorption near-edge spectroscopy (XANES) measurements on 1:2:2 compounds of the form RT/sub 2/X/sub 2/ with R = Ce and Eu, T = a transition metal, and X = Si or Ge are presented. XANES measurements on each of the three sublattices are used to elucidate elements of the electronic structure of these compounds. In particular, the ...
Near edge x-ray absorption fine structure (NEXAFS) spectroscopy at the nitrogen and carbon K-edges was used to study the hydration of adenosine triphosphate in liquid microjets. The total electron yield spectra were recorded as a function of concentration, pH, and the presence of sodium, magnesium, and copper ions ...
The x-ray absorption near-edge structure (XANES) spectroscopy has been used as a ``fingerprint'' to address the unresolved issues related to the changes in the local structure around As and to identify its chemical state in the As-doped, p-type ZnO. The spectral features of both As K- and O K-edge XANES spectra strongly suggest that in ...
The oxidation state of Cr in 200 [mu]m regions within individual lunar olivine and pyroxene grains from lunar basalt 15555 was inferred using X-ray Absorption Near Edge Structure (XANES). Reference materials had previously been studied by optical absorption spectroscopy and included Cr-bearing ...
The oxidation state of Cr in 200-micron regions within individual lunar olivine and pyroxene grains from lunar basalt 15555 was inferred using X-ray Absorption Near Edge Structure (XANES). Reference materials had previously been studied by optical absorption spectroscopy and included Cr-bearing ...
Near edge x-ray absorption fine structure (NEXAFS) and infrared reflection-absorption spectroscopy (IRRAS) have been used to study the orientational behavior of thin films of poly(3-methylthiophene) electrochemically polymerized on a platinum surface. Clear orientational effects, with the ...
Arsenic is present in low concentrations in much of the Earth's crust and changes in its speciation are vital to understanding its transport and toxicity in the environment. We have used X-ray absorption spectroscopy to investigate the coordination sites of arsenic in a wide variety of samples, including soil and earthworm tissues from ...
Arsenic is present in low concentrations in much of the Earth's crust and changes in its speciation are vital to understanding its transport and toxicity in the environment. We have used X-ray absorption spectroscopy to investigate the coordination sites of arsenic in a wide variety of samples, including soil and earthworm tissues from arsenic-contaminated ...
The reduction-oxidation cycling of the nickel-based oxides in composite solid oxide fuel cells and battery electrodes is directly related to cell performance. A greater understanding of nickel redox mechanisms at the microstructural level can be achieved in part using transmission x-ray microscopy (TXM) to explore material oxidation states. X-ray nanotomography combined with x-ray ...
The inner shell excitation of pyrimidine and some halogenated pyrimidines near the C and N K-edges has been investigated experimentally by near edge x-ray absorption fine structure spectroscopy and theoretically by density functional theory calculations. The selected targets, 5-Br-pyrimidine, 2-Br-pyrimidine, ...
Bulk amorphous PdCuNiP alloys have been prepared from the liquid state by means of solidification under an argon atmosphere. The addition of a small amount of Fe ({approx}5 at. %) results in the formation of nanocrystalline inclusions inside the residual amorphous matrix. Element-specific near-edge x-ray absorption fine-structure ...
GaN samples implanted with O, Ar, Te, Xe and Au ions, at fluences high enough to cause the formation of an amorphous surface or buried layer, are studied using Raman, X-ray absorption near-edge structure (XANES) and Rutherford backscattering (RBS) spectroscopies. The amorphous character of the as-implanted layers is verified by RBS and ...
Prostate cancer is one of the most commonly diagnosed cancers in men throughout the world. It is believed that changes to the structure of protein binding sites, altering its metabolism, may play an important role in carcinogenesis. Sulphur, often present in binding sites, can influence such changes through its chemical speciation. Hence there is a need for precise investigation of coordination ...
Recent developments in analytical instrumentation have led to revolutionary discoveries in cosmochemistry. Instrumental advances have been made along two lines: (i) increase in spatial resolution and sensitivity of detection, allowing for the study of increasingly smaller samples, and (ii) increase in the precision of isotopic analysis that allows more precise dating, the study of isotopic ...
An x-ray spectrometer devoted to dynamical studies of transient systems using the x-ray absorption fine spectroscopy technique is presented in this article. Using an ultrafast laser-induced x-ray source, this optical device based on a set of two potassium acid phthalate conical crystals allows the extraction of x-ray absorption ...
X-ray absorption near-edge spectroscopy (XANES) of the L1- and L3-edges of transition metals (W, Re, Ir) oxides has been studied in the ``ADONE'' synchrotron source. The distortion of oxygen polyhedra and the metal valence state correlate with the amplitude of the pre-edge peak in L1-spectra and the ``white line'' in L3-spectra.
Samples of sewage sludges proposed for use as soil ameliorants in an Indo-Canadian project were tested for chromium content. Standard aqua regia extractions found one sludge to have excessive amounts of Cr. X-ray absorption near-edge structure (XANES) spectroscopy, however, indicated that the Cr was present in the relatively benign ...
STXM and C-NEXAFS (carbon near edge absorption micro-spectroscopy) microanalysis were used to analysis the microchemistry of cokes and highly carbonaceous materials. The issue of molecular orientation is addressed by using the intrinsic polarization of the x-ray beam at X1A beamline at NSLS.
High resolution adsorption isotherms, temperature programmed desorption (TPD), x-ray diffraction (XRD) and x-ray absorption near edge spectroscopy (XANES) methods were used to investigate the interaction of SO(sub 2) with high quality MgO powders. The res...
Micro-X-ray fluorescence (�-XRF) microprobe analysis and micro-X-ray absorption near edge spectroscopy (�-XANES) were employed to identify Fe and Mn phases and their association with selected toxic elements in two biosolids (limed composted and Nu-Earth) containing low ...
EPA Science Inventory
We describe here a new, non-destructive method for valence determinations of vanadium and oxygen fugacity estimates for basaltic glasses with spatial resolution of a few micrometers using synchrotron x-ray absorption near edge structure (XANES) spectroscopy.
by optical microscopy (OM) and Raman spectroscopy, to identify single layers of graphite and thicker flakes-structure (NEXAFS) spectrum of a single layer of graphite (graphene) obtained by micromechanical cleavage of highly ordered pyrolytic graphite on a SiO2 substrate. We utilized a photoemission electron microscope
Electron microprobe analyses were made using a Cameca SX100 at the NASA Johnson Space Center. Measurements of the valence of V were made using synchrotron micro-XANES (X-ray Absorption Near-Edge Structure) spectroscopy (SmX), at the Advanced Photon Source...
Heat treatment of graphene oxide (GO) with ammonia flow at various temperatures resulted in different distribution of nitrogen species. Synchrotron based X-ray absorption near-edge structure (XANES) spectroscopy provides unambiguous evidence for the presence of three nitrogen species. The Pt/NG-800 composite exhibits outstanding ...
The nanographite grains, the diameter of which was around 5 nm, were formed on Pt(111) by exposing the Pt(111) substrate to benzene gas at room temperature and annealing it up to 850 K. The increase of relative number of edge atoms enabled the observation of edge-derived electronic states. The measurement of ultraviolet photoelectron spectroscopy and near ...
This paper reports results from XANES (X-ray absorption near edge spectroscopy) studies during polarization of thin sputter-deposited Fe-oxide films in acidic solutions. The dissolution rate of Fe-oxides in acidic solutions was found to be strongly increa...
Quantitative knowledge of the fundamental structure and substrate binding, as well as the direct measurement of conformational changes, are essential to the development of self-assembled monolayers (SAMs) and surface-attached interlocking molecules, caten...
Soft X-ray imaging and carbon near edge absorption fine structure spectroscopy (C-NEXAFS) has been used for the in-situ analysis of sporinite in a rank variable suite of organic rich sediments extending from recent up to high volatile A bituminous coal. T...
Ti and V valence in spinels from a Type B1 CAI and an experimental sample run under reducing conditions were determined by X-ray absorption near edge spectroscopy (XANES). The Ti4+-rich cores of spinels are not in equilibrium with the host mineral.
The effects of alpha irradiation in the rare-earth silicate, Ca2Nd8(SiO4)6O2, was investigated by x-ray diffraction, x-ray absorption near-edge spectroscopy (XANES), and extended x-ray fine structure (EXAFS) techniques. Irradiation with alpha particles em...
The goals of the study are (1) to use X-ray absorption near-edge spectroscopy (XANES) to determine forms of chlorine (inorganic, ionic, and organic) and forms of organic sulfur (organic sulfide and thiophenic sulfur) in as-shipped coals from Illinois mine...
The research activities are summarized here for the following subjects: (1) confinement of block copolymers; (2) free surface confinement; (3) effects of substrate interactions; (4) random copolymers at homopolymer interfaces; (5) phase separation in thin films polymer mixtures; (6) buffing of polymer surfaces; and (6) near edge x-ray ...
We present XANES at the L(sub III) edge for four plutonium solid phases: Pu(III)F(sub 3), Pu(IV)O(sub 2), NaPu(V)O(sub 2)CO(sub 3), and Ba(sub 3)Pu(VI)O(sub 6). These correspond to the four important oxidation states in the process chemistry and environme...
High-quality films of copper phthalocyanine (CuPc) prepared in situ were used as a model to characterize unoccupied states of organic molecular semiconductors. We demonstrate that a combination of high-resolution near-edge x-ray absorption together with first-principles calculations constitutes a reliable tool for the detection and identification of ...
An analysis protocol that combines X-ray absorption near-edge structure spectroscopy with selective leaching has been developed to examine hazardous species in size- segregated particulate matter (PM) samples derived from the combustion of fossil fuels. The protocol has been used...
to the formation of protonated surface groups, and (2) the change in surface charge due to HA sorption. Boron KAdsorption of Boric Acid on Pure and Humic Acid Coated am-Al(OH)3: A Boron K-Edge XANES Study D A N. Boron (B) K-edge X-ray absorption near-edge structure (XANES) spectroscopy was used to investigate
Hard x-ray absorption spectroscopy is combined with scanning microtomography to reconstruct full near-edge spectra of an elemental species at each location on an arbitrary virtual section through a sample. These spectra reveal the local concentrations of different chemical compounds of the absorbing element inside the sample and give ...
We study the electronic structure of three-dimensional nanoporous CeO2?x monoliths (aerogels) by soft x-ray absorption near-edge structure (XANES) spectroscopy. Atomic multiplet calculations are used to interpret high-resolution CeM4,5 - and N4,5 -edge XANES spectra. Results show that aerogels with thicker ligaments, but with the ...
Journal of Electron Spectroscopy and Related Phenomena 154 (2007) 60�62 Investigation of vanadium. Keywords: XANES; Vanadium�sodium silicate glasses; V L2,3 edges; O K edge 1. Introduction Studies on oxide vanadium-sodium silicate glasses. X-ray absorption near edge structure (XANES) ...
Direct comparisons between surface and bulk of diverse materials can be made by simultaneous electron yield (5 nm depth sensitivity) and fluorescence yield (200 nm) ultra soft x-ray absorption spectroscopy measurements utilizing a rapid sample interchange apparatus. For example the orientations of functional groups have been characterized at and near the ...
The authors have used x-ray absorption to measure the binding energy, x-ray absorption near-edge structure (XANES), and extended x-ray absorption fine structure (EXAFS) of Pt particles in L-zeolite saturated with H{sub 2} at room temperature and after desorption of H{sub 2} in He. The desorption of H{sub 2} causes ...
Chemical bath deposition (CBD) offers a simple and inexpensive route to deposit semiconductor nanostructures, but lack of fundamental understanding and control of the underlying chemistry has limited its versatility. Here we report the first use of in situ X-ray absorption spectroscopy during CBD, enabling detailed investigation of both reaction mechanisms ...
We demonstrate the feasibility of Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy on solids by means of femtosecond soft x-ray pulses from a free-electron laser (FEL). Our experiments, carried out at the Free-Electron Laser at Hamburg (FLASH), used a special sample geometry, spectrographic energy ...
Synchrotron x-ray absorption near edge structures (XANES) measurements of In L{sub 3} edge is used in conjunction with first principles calculations to characterize rf magnetron sputtered indium oxynitride at different O contents. Good agreement between the measured and the independently calculated spectra are obtained. Calculations ...
Ti K and Ti L{sub 2,3} x-ray absorption fine-structure near-edge spectra of SrTiO3 thin films grown coherently on Si(001) reveal the presence of a ferroelectric (FE) distortion at room temperature. This unique phase is a direct consequence of the compressive biaxial strain achieved by coherent epitaxial growth.
The degree of chlorination in chlorinated, vulcanized natural rubber was determined by X-ray absorption near-edge spectroscopy (XANES). The vulcanized natural rubber samples were prepared in film with thickness of 180 ?m, approximately. They were treated with chlorination solution with different immersion times ranging from 0.5 to 30 ...
Scanning transmission X-ray microscopy was used to chemically image RuO(2) nano-layer coated multi-walled carbon nanotubes (RuO(2)/MWCNT) with a spatial resolution of 30 nm. X-Ray absorption near-edge structure spectroscopy of individual RuO(2)/MWCNTs has been compared with that of MWCNTs and RuO(2) which confirms that RuO(2) interacts ...
This paper identifies two-different regimes of nanocrystallinity: (i) thin films with nanocrystallites >3 nm, and (ii) thin films with nanocrystallites {<=}2 nm. Near edge X-ray absorption spectroscopy, and soft-X-ray photoelectron spectroscopy, combined with visible and ...
The utility of sulfur K-edge X-ray absorption spectroscopy for the determination and quantification of sulfur forms in petroleum asphaltenes has been investigated. Both X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectra ...
X-ray absorption methods have been successfully used to obtain quantitative information about local atomic composition of two different materials. X-ray Absorption Near Edge Structure analysis and X-Ray Photoelectron Spectroscopy allowed us to determine seven chemical compounds and their ...
The valence of Cu and Au in YBa2Au0.3Cu2.7O7-delta was investigated using X-ray absorption near edge
The valence of Cu and Au in YBa2Au0.3Cu2.7O7-delta was investigated using x-ray absorption near edge
La-doped barium titanate (Ba1-xLaxTiO3) is an important electronic ceramic material used in a wide variety of applications including in multilayer capacitor, transducers, ferroelectric thin film memories, and positive temperature coefficient resistor (PTCR). In this work, we investigated the changes of the local atomic structure around barium and titanium ions of Ba1-xLaxTiO3 compounds prepared by ...
A high average power broadband x-ray source is developed in the multi-keV range, based on the thermal emission of plasmas produced with a 1 kHz fs laser focused on high Z element target. This compact ultrafast x-ray source is used to measure the x-ray absorption near-edge spectroscopy of aluminum K-edge (1.559 keV) with noise lower ...
Peridinin-chlorophyll a protein (PCP) is a unique water soluble antenna complex that employs the carotenoid peridinin as the main light-harvesting pigment. In the present study the near edge X-ray absorption fine structure (NEXAFS) spectrum of PCP was recorded at the carbon K-edge. Additionally, the NEXAFS spectra of the constituent ...
In the past decades, environmental scientists have become increasingly involved in developing novel approaches for applying emerging spectroscopic techniques to complex environmental matrices. The objective of this review is to convey the most common chemical species of phosphorus reported for soils, sediments, model systems, and waste materials based on analyses by four spectroscopic techniques: ...
Near-edge x-ray absorption fine structure spectroscopy (NEXAFS) is a powerful tool for determination of molecular orientation in self-assembled monolayers and other surface-attached molecules. A general framework for using NEXAFS to simultaneously determine molecular tilt and twist of rigid molecules attached to surfaces is presented. ...
Examination of the adsorption mechanism of Tl and Cr on selected mineral oxides was carried out by X-ray Absorption Spectroscopy (XAS) using synchrotron radiation. Information on the oxidation states of surface bound species was obtained from the low energy side of XAS spectra, the XANES (X-ray Absorption Near ...
In order to understand the evolving world of environmental issues, the ability to characterize and predict the stability and bioavailability of heavy m�tal contaminants in mine waste is becoming increasingly more important. X-ray Absorption Near Edge Structure (XANES) and Extended X-ray Absorption Fine Structure ...
Chemical bonding states of titanium compounds in LiH and LiNH2 mixture, which have been a candidate for a hydrogen storage material, have been examined by x-ray absorption spectroscopy measurement as the characterization of the catalysts. The results of x-ray absorption near-edge structure indicated that the Ti ...
The identification of ligands in metalloorganic complexes is crucial for understanding many important biological and chemical systems. Nonresonant K? valence-to-core X-ray emission spectroscopy (XES) has been demonstrated as a ligand identification technique which is complementary to other spectroscopies, such as X-ray absorption. In ...
Elucidation of the inorganic materials within coals is important for coal processing, since these compounds may function as in situ catalysts for coal liquefaction. In addition, these species will have to be separated from the organic species prior to the use of coal as a fuel or chemical feedstock. In recent years, x-ray absorption spectroscopy (XAS) has ...
High-resolution x-ray absorption near edge structure spectroscopy was used to characterize the metal sites in three different cobalt-substituted derivatives of Carcinus maenas hemocyanin (Hc), including a mononuclear cobalt, a dinuclear cobalt and a copper-cobalt hybrid derivative. Co(II) model complexes with ...
One of the long term research goals has been to attain a quantitative theory of deep core X-ray spectroscopies. These spectroscopies include X-ray absorption fine structure (XAFS), X-ray absorption near edge structure (XANES), X-ray magnetic circular dichroism (XMCD), ...
Application of in situ X-ray absorption near-edge spectroscopy (XANES) at the Al K-edge provides unique insight into the flexibilty of the aluminum coordinations in zeolites as a function of treatment or during true reaction conditions. A unique, previously not observed, pre-edge feature is detected in zeolites H-Mordenite and steamed ...
The carbonic anhydrase (CA) family of zinc metalloenzymes includes many known isozymes that have different subcellular distributions. The study described here focuses on identification of the structural features that define low-temperature adaptation in a Chionodraco hamatus protein, both for the reaction center, at an atomic level, and for the tertiary structure of the protein. To this aim, an ...
Sulfur species in soils and sediments have previously been determined indirectly using destructive techniques. A direct and more accurate method for S speciation would improve our understanding of S biogeochemistry. X-ray absorption near edge structure (XANES) spectroscopy was performed on purified humic and fulvic ...
Using X-ray absorption near-edge structure spectroscopy (XANES), we investigate the local electronic structure of phosphorus (P) and its chemical valence in laser-ablated n- type ( as- grown), and p- type ( annealed) P-doped ZnO thin films. Both the P L 1- and P L 2,3-edge XANES spectra reveal that the valence state of P is 3? (P3?) in ...
A goethite-based catalyst was evaluated using in-situ X-ray absorption near-edge structure (XANES) spectroscopy during methane oxidation under increasing reaction temperature. Determination of rank by median absolute deviation (DRMAD), evolving factor analysis (EFA), and multivariate curve resolution (MCR) were used to detect the ...
To improve paint adhesion and extend protection of carbon (C) steel surfaces exposed to a variety of environmental conditions, these surfaces typically are phosphatized. These iron phosphate-based conversion coatings require a chromic acid sealing rinse for enhanced performance. However, the use of chromate increasingly is being limited because of the safety problems of handling carcinogenic ...
This study addresses the need for methods that validate the surface chemistry leading to the immobilization of biomolecules and provide information about the resulting structural configurations. We report on the use of near edge x-ray absorption fine structure spectroscopy (NEXAFS) to characterize a widely employed ...
The carbon {ital K}-shell near-edge absorption fine structure of both diamond and graphite has been calculated by the multiple-scattering method and by a single-particle self-consistent pseudo-atomic-orbital band-theory method. We compare the results of these two calculations with experiment, and show that they both give agreement with the experimental ...
Recent developments in the understanding of the biosynthesis of the active site of the nitrogenase enzyme, the structure of the iron centre of [Fe]-hydrogenase and the structure and biomimetic chemistry of the [FeFe] hydrogenase H-cluster as deduced by application of X-ray spectroscopy are reviewed. The techniques central to this work include X-ray ...
We report on Mn K-edge X-ray absorption study, in plane and out of plane, of La0.7Sr0.3MnO3 films, epitaxially grown on a tensile substrate SrTiO3 by laser ablation. From Extended X-ray Absorption Fine Structure in the film plane we observe a small increase of Mn-Mn distances with respect to relaxed film. In addition, a small distortion of the MnO6 ...
Automation of x-ray absorption spectroscopic (XAS) data reduction is essential to cope with high-throughput data collection becoming available at an increasing number of synchrotron radiation centers. A flexible script called KEMP has been developed and implemented at the XAS beamline at EMBL Hamburg. It automatically processes fluorescence XAS data. The pipeline includes dead ...
The speciation and quantification of sulfur species based on sulfur K-edge x-ray absorption spectroscopy is of wide interest, particularly for biological and petroleum science. These tasks require a firm understanding of the sulfur 1s near-edge x-ray absorption fine structure (NEXAFS) spectra of relevant species. ...
Experimental L(III) X-ray absorption near edge structure (XANES) spectra of the distorted octahedral neptunium oxo ions NpO(2)(OH)(4)(2-), NpO(4)(OH)(2)(3-), and NpO(6)(6-) are interpreted using relativistic full multiple scattering calculations of the X-ray absorption process. In this series of compounds, the ...
This work reports a theoretical x-ray absorption near-edge structure (XANES) spectroscopy study at the Ti K-edge in TiO(2) rutile. We present detailed ab initio computations of the Ti K-edge XANES spectrum performed within the multiple-scattering framework. An extensive discussion is presented concerning the size of the cluster needed ...
This work reports a theoretical x-ray absorption near-edge structure (XANES) spectroscopy study at the Ti K-edge in TiO2 rutile. We present detailed ab initio computations of the Ti K-edge XANES spectrum performed within the multiple-scattering framework. An extensive discussion is presented concerning the size of the cluster needed to ...
A soft-chemistry method is used to synthesize zinc ferrite nanoparticles to prepare a magnetic fluid. We investigate here their internal structure by X-ray Absorption Near Edge Spectroscopy (XANES) and X-Ray Diffraction (XRD). A cross analysis of XANES and Rietveld refinement of XRD spectra shows non-equilibrium ...
Copper and zinc phthalocyanines and porphyrins are used in organic light emitting diodes and dye-sensitized solar cells. Using near edge x-ray absorption fine structure (NEXAFS) spectroscopy at the Cu 2p and Zn 2p edges, the unoccupied valence states at the Cu and Zn atoms are probed and decomposed into 3d and 4s ...
We present recent results on the characterization of highly ordered polycrystalline thin films of the charge transfer salt TTF-TCNQ (TTF=tetrathiafulvalene, TCNQ=tetracyanoquinodimethane) prepared by thermal sublimation in high vacuum under different conditions. The increase in orientation and microcrystal size as a function of substrate and annealing temperatures is addressed. A consequence of ...
The role of biotic Np(V) reduction is studied in light of its potential role in the environmental immobilization of this hazardous radionuclide. The speciation of Np in Desulfovibrio desulfuricans cultures is compared with Np speciation in the spent medium and in the uninoculated medium. Precipitates formed in all three samples. Optical spectroscopy and X-ray ...
To understand the many important functions of sulfur, a ubiquitous element in biological systems, in the environment and for industrial applications, detailed analyses are needed. Characterization of the variety of sulfur functional groups in a natural sample, often occurring in a wide range of oxidation states, became possible when the development of dedicated X-ray ...
X-ray absorption near-edge structure spectroscopy (XANES) used to measure sulfur speciation in a variety of organic-rich marine sediments has established sulfonates as a novel and major components of sedimentary organic sulfur. The origins of sulfonates in sediments are not clear, although both biological and geochemical mechanisms are ...
X-ray absorption near-edge structure spectroscopy (XANES) used to measure sulfur speciation in a variety of organic-rich marine sediments has established sulfonates as a novel and major component of sedimentary organic sulfur. The origins of sulfonates in sediments are not clear, although both biological and geochemical mechanisms are ...
The sorption reactions of arsenate (As(V)) and arsenite (As(III)) on RuO2 x H2O were examined by X-ray Absorption Near Edge Spectroscopy (XANES) to elucidate the solid state speciation of sorbed As. At all pH values studied (pH 4-8), RuO2 x H...
We report room temperature ferromagnetism in partially hydrogenated epitaxial graphene grown on 4H-SiC(0001). The presence of ferromagnetism was confirmed by superconducting quantum interference devices measurements. Synchrotron-based near-edge x-ray absorption fine structure and high resolution electron energy loss spectroscopy ...
The microstructure and composition of the layers of two giant avian eggshells were investigated using a combination of scanning electron microscopy, electron probe microanalyses, and X-ray absorption near-edge structure spectroscopy (XANES). The two species have some similarities and differences in their microstructure and composition; ...
Speciation of copper in waste incineration fly ashes (dry scrubber (DS) and bag filter (BF)) has been studied by X-ray absorption near edge structural (XANES) spectroscopy in the present work. Copper species such as metallic Cu, CuO, Cu(OH)2, and a small amount of CuCO3 in the fly ashes could be distinguished by ...
We analyze the structure of Haliotis rufescens nacre, or mother-of-pearl, using synchrotron spectromicroscopy and x-ray absorption near-edge structure spectroscopy. We observe imaging contrast between adjacent individual nacre tablets, arising because different tablets have different crystal orientations with respect to the ...
The adsorption of the aromatic amino acid, phenylalanine on a TiO2 rutile (1 1 0) single crystal surface has been investigated with photoemission and NEXAFS (near edge X-ray absorption fine structure) spectroscopy. The results indicate initial adsorption via the carboxylate group in a bidentate configuration with ...
Surface segregation of end-functional poly(2-vinylpyridine) in a blend with P2VP was measured by X-ray photoelectron spectroscopy. A series of chain end functionalized P2VP homopolymers were synthesized via either anionic polymerization or Reversible Addition Fragmentation Chain Transfer (RAFT) and end capped with either a single fluorinated oligomer or a perfluorinated ...
In this work we employ the state of the art pseudopotential method, within a generalized gradient approximation to the density functional theory, to investigate the adsorption process of furan on the silicon (001) surface. A direct comparison of different adsorption structures with x-ray photoelectron spectroscopy (XPS), ultra-violet photoelectron ...
Knowledge of phosphorus (P) species in P-rich soils is useful for assessing P mobility and potential transfer to ground water and surface waters. Soil P was studied using synchrotron X-ray absorption near-edge structure (XANES) spectroscopy (a nondestructive chemical-speciation technique) and sequential chemical fractionation. The ...
The x-ray absorption spectroscopy (XAS) had been an essential tool to gather spectroscopic information about atomic energy level structure in the early decades of this century. It has also played an important role in the discovery and systematization of rare-earth elements. The discovery of synchrotron radiation in 1952, and later the availability of ...
Since the first experiment on an intense synchrotron radiation source ten years ago, EXAFS (Extended X-ray Absorption Fine Structure) and XANES (X-ray Absorption Near Edge Structure), have become a routine technique for investigating the environment of me...
Hard x-ray absorption spectroscopy is combined with scanning microtomography to reconstruct full near edge spectra of an elemental species at each point on an arbitrary virtual section through a sample. These spectra reveal the local concentration of different chemical compounds of the absorbing element inside the ...
We propose to extend our state-of-the-art, ab initio XAFS (X-ray absorption fine structure) codes, FEFF. Our current work has been highly successful in achieving accurate, user-friendly XAFS standards, exceeding the performance of both tabulated standards and other codes by a considerable margin. We now propose to add the capability to treat more complex materials. This ...
X-ray Photo Emission Electron Microscopy (X-PEEM) and Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy were applied to study the properties of amorphous hard carbon overcoats on disks and sliders, and the properties of the lubricant. The modification of lubricants after performing thermal desorption ...
The characterization of an iron-containing natural zeolitic sample from the deposit of Tasajeras (Cuba) has been carried out by means of X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS),57Fe M�ssbauer spectroscopy and Fe K-edge X-ray ...
Fly ashes collected from waste heat boilers in the incineration process may possess representative chemical structure of toxic metals during incineration and their changes in the quench process at 1125 553 K and 503 493 K, respectively. Note that copper may play an important role in catalytic formation of dioxins during incineration. Speciation of copper in the fly ashes has, therefore, been ...
The molecular orientations of hexadecafluorophthalocyanatozinc (F16ZnPc) vacuum-deposited on Au and Mg substrates were studied by near edge X-ray absorption fine structure (NEXAFS) spectroscopy and infrared reflection-absorption spectroscopy. The molecular planes of F16ZnPc ...
We have investigated the nature of the residual damage in diamond crystals following the ion implantation/graphitization ``lift-off'' process, using near-edge x-ray absorption fine structure spectroscopy and transmission electron microscopy. A defective but crystalline interface is found, which displays dense pre-edge unoccupied states ...
Applications of x-ray absorption near-edge spectroscopy (XANES) and the design of cells for in situ corrosion studies are reviewed. Passive films studies require very thin metal or alloy layers be used having a thickness of the order of the films formed because of penetration of the x-ray beam into the metal substrate. The depth of ...
The electronic structures of HgII, NiII, CrIII, and MoV complexes with cysteine were investigated by sulfur K-edge X-ray absorption near-edge structure (XANES) spectroscopy and density functional theory. The covalency in the metal-sulfur bond was determined by analyzing the intensities of the electric-dipole allowed pre-edge features ...
We have investigated the electronic structure of GaInN semiconductors by performing x-ray absorption near-edge fine structure (XANES) spectroscopy at Ga K-edge and self-consistent-field real-space multiple-scattering theory calculations. It was demonstrated that the nondestructive Ga K-edge XANES spectra can be used as the fingerprints ...
The electronic properties of amorphous carbon nitride were studied by x-ray-absorption near-edge structure (XANES) and valence-band photoelectron spectroscopy (PES). The nitrogen incorporation was found to induce graphitization, as evidenced by an increase of the sp2 cluster in C and N K-edge XANES spectra. The structure is found to be ...
The electronic structures of Hg{sup II}, Ni{sup II}, Cr{sup III}, and Mo{sup V} complexes with cysteine were investigated by sulfur K-edge X-ray absorption near-edge structure (XANES) spectroscopy and density functional theory. The covalency in the metal-sulfur bond was determined by analyzing the intensities of the electric-dipole ...
LiFePO4 composite was synthesized by both solid state and hydrothermal methods. The physical properties of the as-prepared lithium iron phosphates were characterized by X-ray diffraction while electrochemical properties were measured with charge/discharge experiments. X-ray absorption spectroscopy (XAS) was performed to investigate the local structure ...
X-ray absorption spectroscopy methods are presented as a useful tool to determine local structure, composition and magnetic moments as well as to estimate the effective anisotropy of substrate supported self-assembled arrays of wet-chemically synthesized FePt nanoparticles. A compositional inhomogeneity within the nanoparticles yields reduced magnetic ...
Ultrafast X-ray absorption near edge spectroscopy has been carried out for photo excited iron pentacarbonyl in ethanol with 2 picosecond resolution. A temporal resolution limited dissociation process was observed, followed by the formation of the mono-substituted complex Fe(CO)(4)EtOH within a few tens of ...
The bonding of hexanethiols to gold nanoparticles of 1.5, 2.0, and 3 nm was studied using x-ray absorption near-edge spectroscopy (XANES) and extended x-ray absorption fine structure (EXAFS). The XANES spectra revealed that a substantial fraction of weakly bound hexanethiol molecules are present in addition to ...
The bonding of hexanethiols to gold nanoparticles of 1.5, 2.0, and 3nm was studied using x-ray absorption near-edge spectroscopy (XANES) and extended x-ray absorption fine structure (EXAFS). The XANES spectra revealed that a substantial fraction of weakly bound hexanethiol molecules are present in addition to ...
The oxidation state of nickel in a nickel oxide battery has been examined using X-ray absorption spectroscopy. Chemically synthesized {beta}-NiOOH and BaNiO{sub 3} were used as reference standards for the Ni(III) and Ni(IV) oxidation states of nickel, respectively. The shift of the Ni K-edge absorption in both a completely charged ...
The coordination structures of U(IV), Np(IV), and Th(IV) in aqueous solution have been determined by studying the X-ray absorption near edge structure (XANES) of the actinide (An) L(3)-edge absorption spectra. The high sensitivity of XANES to the bonding geometry provides an unambiguous determination of the ...
The chemical speciation of sulfur in heavy petroleums, petroleum source rock extracts, and source rock pyrolysis products was studied using X-ray absorption near-edge structure (XANES) spectroscopy. The good energy resolution (ca. 0.5 eV) at the sulfur K edge and the strong dependence of XANES on the sulfur environment combine to give ...
Molecular orientation of thin films of silicon phthalocyanine (SiPc) compounds on highly oriented pyrolytic graphite (HOPG) was investigated by near edge X-ray absorption fine structure (NEXAFS) and X-ray photoelectron spectroscopy (XPS). The films were prepared by a casting method using solution of SiPc ...
X-ray absorption near-edge structure (XANES) is used to study the characteristics of different sites of Mn in the Ga1-xMnxN dilute magnetic semiconductor (DMS) with zinc-blende structure. The XANES spectra of representative Mn occupation sites (substitutional MnGa, interstitial MnI, MnGa-MnI dimer and Mn cluster) in GaN lattice are theoretically calculated ...
X-ray absorption near-edge structure (XANES) spectroscopy was used to investigate the local structures of Fe0.05Si0.95 diluted magnetic semiconductors (DMSs) thin film deposited by radio-frequency (RF) reactive magnetron co-sputtering device at temperatures of room-temperature (RT), 473K and 573K. Using the ab inito self-consistent ...
X-ray absorption near-edge structure (XANES) and x-ray excited optical luminescence (XEOL) have been used to study the optical properties of 2,5,8,11-tetra-tert-butylperylene (TBPe) polyhedral crystals with morphology varies from cube to rhombic dodecahedron. Benefit from the high resolution of synchrotron radiation spectroscopy, C 1s ...
The chlorine x-ray absorption near-edge structure (XANES) spectra of five Illinois coals and three British coals, and two series of char samples were examined. The char samples were prepared by stepwise heating one Illinois and one British coal in air at temperatures from 200 to 650{degrees}C. The chlorine XANES spectra for all the coals are similar and ...
We previously reported scanning transmission X-ray microscope (STXM) C mapping, X-ray absorption near-edge structure (XANES) spectroscopy, and Fourier transform infrared (FTIR) spectroscopy on a carbonate globule and opaque "rim material" from the ALH 84001 meteorite. The globule was consistent with the material ...
Speciation of titanium in the CuO/TiO2 thin film (synthesized by radio frequency magnetron sputtering) during photocatalytic decomposition of CHCl3 has been studied by in situ X-ray absorption near-edge structural (XANES) spectroscopy. Little perturbation was observed in the Ti K-edge XANES spectra of the CuO/TiO2 during ...
Octadecyl phosphoric acid ester has been found to produce oriented, well-ordered monolayers on a flat tantalum(V) oxide surface, via self-assembly from a heptane/propan-2-ol solution. By means of contact angle, optical waveguide lightmode spectroscopy (OWLS), near-edge X-ray absorption fine structure spectroscopy ...
Employing synchrotron X-ray absorption near-edge spectroscopy (XANES) combined with X-ray fluorescence (XF) and reflectivity (XR) techniques, we monitor the state of ferrous and ferric iron as it binds to charged carboxylic and phosphate groups. By subphase pH manipulation, arachidic acid and dihexadcyl phosphate monolayers can provide ...
... Experimental K-edge NEXAFS (near edge X-ray absorption fine structure) data for solid Ne are compared with theoretical results. ...
... Recently, Near Edge X-ray Absorption Fine Structure (NEXAFS ... Using the highly polarized x-ray beam of the ... The carbon k-edge NEXAFS spectra of ...
Jun 16, 2011 ... Title: Novel visualization studies of lignocellulosic oxidation chemistry by application of C-near edge X-ray absorption fine structure ...
Treesearch
Plant hyperaccumulation of the essential nutrient manganese (Mn) is a rare phenomenon most evident in the Western Pacific region, and differs from hyperaccumulation of other elements. Mn hyperaccumulators employ a variety of species-dependent spatial distribution patterns in sequestering excess foliar Mn, including primary sequestration in both nonphotosynthetic and photosynthetic tissues. This ...
We investigated different AlN nano-systems using spectroscopic methods. Experiments were performed at the Synchrotron Radiation Facility of the Laboratori Nazionali di Frascati using both XANES (x-ray absorption near edge spectroscopy) and FTIR (Fourier transform infrared spectroscopy) ...
Structural investigations of the short range order around iridium and oxygen ions in nanocrystalline iridium oxide thin films, prepared by dc magnetron sputtering technique, were performed by x-ray absorption spectroscopy. The Ir L3-edge extended x-ray absorption fine structure and the O K-edge x-ray absorption ...
Smalt was commonly used as a pigment by artists between the 16th and 18th centuries. It is a powdered blue potash glass colored by cobalt ions and often degrades causing dramatic changes in the appearance of paintings. The aim of the work presented in this paper was to investigate the changes in the structure and environment around the cobalt ion on deterioration, to further our understanding of ...
Crystallographic structure, growth induced miscibility gap and strain in Ta/Co100?xPtx (0 <= x <= 43 at%)/Ru/Ta/glass films deposited at ambient temperature were investigated using polarized x-ray absorption spectroscopy to clarify the origin of observed perpendicular magnetic anisotropy (PMA) in Co72Pt28 film. Extended x-ray ...
An in situ procedure for quantifying total organic and inorganic Cl concentrations in environmental samples based on X-ray absorption near-edge structure (XANES) spectroscopy has been developed. Cl 1s XANES spectra reflect contributions from all Cl species present in a sample, providing a definitive measure of total Cl concentration in ...
We use time-resolved x-ray absorption near-edge structure spectroscopy to investigate the electronic dynamics associated with the photoinduced insulator-to-metal phase transition in the colossal magnetoresistive manganite Pr{sub 0.7}Ca{sub 0.3}MnO{sub 3}. Absorption changes at the O K and Mn L edges directly ...
We have measured the near-edge x-ray-absorption fine-structure spectra of the {ital K} edge of potassium in the polymer-salt complex poly(ethylene oxide)-KI. Changes are observed as a function of temperature due to modifications of the K-ion coordination. Comparison with model systems suggests that the lower activation energy of this ionic conducting polymer complex at ...
Direct liquefaction studies were conducted on a washed, commingled waste plastic (CWP), as received from the American Plastics Council and after addition of 5 wt.% of polyvinyl chloride (PVC). Both non-catalytic and catalytic experiments were performed the catalytic experiments utilized 1 wt.% of HZSM-5. The experiments on the CWP-PVC mixture were conducted with and without the addition of 5 wt.% ...
Gold clusters supported on Al2O3 and TiO2 have been exposed to different mixtures of CO and O2. Their structure has been probed in situ using X-ray absorption spectroscopy (XAS) at the Au L3-edge. In all materials, the dominant phase during catalysis is Au0. Both samples show variations of the electronic structure of the gold clusters with changing ...
Angle-dependent x-ray absorption near edge structure (XANES) and scanning photoelectron microscopy (SPEM) measurements have been performed to differentiate local electronic structures of the tips and sidewalls of highly aligned carbon nanotubes. The intensities of both ?*- and ?*-band C K-edge XANES features are found to be ...
Near edge x-ray absorption fine structure (NEXAFS) spectra have been measured at the carbon and nitrogen K-edges of the prototypical aromatic molecule, pyrrole, both in the gas phase and when solvated in water, and compared with spectra simulated using a combination of classical molecular dynamics and first principles density ...
Speciation of copper in the abstraction of nano copper with a room temperature ionic liquid (RTIL) (1-butyl-3-methylimidazolium hexafluorophosphate [C4mim][PF6]) has been studied by X-ray absorption near edge structural (XANES) and extended X-ray absorption fine structural (EXAFS) ...
