L-shell x-ray fluorescence relative intensities for elements with 62≤Z≤83 at 18 keV and 23 keV by synchrotron radiation

The relative intensities of L-subshell x-ray fluorescence(XRF)for elements with atomic numbers 62≤Z≤83 were measured at two excitation energies,18 keV and 23 keV,using a synchrotron radiation source at a beamline of the Synchrotron Light Center for Experimental Science and Applications in the Middle East(SESAME),Jordan.The experimentally measured results of the relative intensities were compared with the calculated results using the subshell fluorescence yield and the Coster-Kronig transition probabilities recommended by Campbell and the values based on the Dirac-Hartree-Slater model by Puri.The experimental and theoretical results are in agreement.In this work,L XRF relative intensities for the elements Sm,Gd,Tb,Er,Ta,W,Re,Hg,Pb and Bi at energies of 18 keV and 23 keV were measured.

Characterization of metal element distributions in the rat brain following ischemic stroke by synchrotron radiation microfluorescence analysis

Ischemic stroke is one of the leading causes of death worldwide,and effective treatment strategies in the chronic phase of this disease remain insufficient.Homeostasis of metals in the brain plays an important role in maintaining normal brain function.However,the dynamic spatial distributions of iron,zinc,calcium,potassium,and copper in a rat brain following ischemic stroke and the association between structural distribution and function remain to be elucidated.In this study,we used a synchrotron radiation-based micro-X-ray fluorescence technique to image element mapping changes in special rat brain regions after ischemic stroke,showing the distribution characteristics of iron,zinc,calcium,potassium,and copper.We demonstrated,for the first time,the consistent dynamic spatial distributions of metal elements at a series of time points(3 h,4.5 h,6 h,12 h,1 d,3 d,5 d,7 d,10 d,14 d,28 d)after brain ischemia,which revealed that the homeostasis of iron,zinc,calcium,potassium,and copper in the brain was disturbed with distinctive change trends,providing clear insights in understanding the underlying pathogenesis of stroke from a novel perspective,thus laying the foundation of further developing new drug targets for stroke treatment.

The Study Internal Structure of the Annual Layers in Lake Sediments Using Synchrotron Radiation with X-ray Focusing Optics

1 Introduction Annually laminated(varve)sedimentary deposits are considered as one of the most important archives,since they offer precise temporal information(years)in combination with high time resolutions.Bottom sediments of the lakes contain detailed geochemical information on

Scan system for arbitrary-shaped samples at the synchrotron radiation facility

X-ray fluorescence(XRF) scan methodology is important for elemental mapping of samples at a synchrotron radiation facility. To save the experiment time and improve the experiment efficiency, one should develop an efficient XRF scan method. In this paper, a new scan mode is presented. It can map arbitrary-shaped areas withou stopping the motors. The control and data acquisition system integrates motor controlling, detector triggering, and data acquisition and storage. The system realizes the arbitrary-shaped 2D-mapping and fluorescence data acquisition synchronously. SR-XRF mapping has been performed with a standard gold mask to verify the validity of this method a beamline BL15U1 of the Shanghai Synchrotron Radiation Facility. The results show that this method reduces the tota scan time and improves the experiment efficiency.

Analysis of nickel distribution by synchrotron radiation X-ray fluorescence in nickel-induced early- and late-phase allergic contact dermatitis in Hartley guinea pigs

Background: Nickel-induced allergic contact dermatitis (Ni-ACD) is a global health problem. More detailed knowledge on the skin uptake of haptens is required. This study aimed to investigate the penetration process and distribution of nickel in skin tissues with late phase and early phase of Ni-ACD to understand the mechanisms of metal allergy. Methods: Forty Hartley guinea pigs were divided into four groups according to the NiSO4 sensitizing concentration and the NiSO4 challenged concentration: the 5% NiSO4-group, 5% to 10%(sensitization-challenge;late phase group);10% NiSO4-group, 10% to 10%(sensitization-challenge;early-phase group);and the positive and negative controls. Pathological biopsies were performed on each group. The depth profile of nickel element concentration in the skin of guinea pigs was detected by synchrotron radiation micro X-ray fluorescence spectroscopy (SR-μ-XRF) and micro X-ray absorption near-edge spectroscopy (μ-XANES). Results: In each section, the nickel element concentration in both the 5% NiSO4-group and 10% NiSO4-group was significantly higher than that in the negative control group. In the upper 300-μm section of skin for the early phase group, the nickel element concentration was significantly higher than that in the lower section of skin. In deeper sections (>200 μm) of skin, the concentration of nickel in the early phase group was approximately equal to that in the late phase group. The curve of the late phase group was flat, which means that the nickel element concentration was distributed uniformly by SR-μ-XRF. According to the XANES data for the 10% NiSO4 metal salt solution, structural changes occurred in the skin model sample, indicating that nickel was not present in the Ni^2+ aqueous ionic state but in the nickel-binding protein. Conclusions: This study showed that the distribution of the nickel element concentration in ACD skin tissue was different between the early phase and late phase groups. The nickel element was not present in the Ni^2+ aqueous ionic state but bound with certain proteins to form a complex in the stratum corneum in ACD model tissue.

In situ analysis of trace elements in metalloproteins of human liver by synchrotron radiation X-ray fluorescence

A method using synchrotron radiation X-ray fluorescence analysis toin situ determine trace elements during protein electrophoretically separating process was established. The distribution of elements in protein bands for human liver cytosolic sample separated by SDS-PAGE was analyzed along polyacrylamide gel. The results showed that the protein fraction of peak III in cytosol was mainly composed of metal ion Zn-associated proteins, being in agreement with that given by atomic absorption spectrometry. Thus, it demonstrated the feasibility of this novel technique forin situ analysis of trace elements in protein bands.

Influence of crystal materials on the synchrotron X-ray fluorescence analysis:a study of crystal and amorphous clinopyroxene

Synchrotron X-ray fluorescence analyses of crystal and amorphous clinopyroxene were compared. The results showed that using the synchrotron X-ray as a source of energy, the diffraction X-ray of crystal materials will seriously affect the X-ray fluorescence analysis. In order to avoid the influence of diffraction, the best way to solve it is to use the monochromatic source, or to have a collimating slit between sample and Si(Li) detector.

First X-ray fluorescence CT experimental results at the SSRF X-ray imaging beamline

X-ray fluorescence CT is a non-destructive technique for detecting elemental composition and distribution inside a specimen. In this paper, the first experimental results of X-ray fluorescence CT obtained at the SSRF X-ray imaging beamline （BL13W1） are described. The test samples were investigated and the 2D elemental image was reconstructed using a filtered back-projection algorithm. In the sample the element Cd was observed. Up to now, the X-ray fluorescence CT could be carried out at the SSRF X-ray imaging beamline.

Synchrotron radiation XRF microprobe investigation of elemental distribution in femoral head slice with osteoporosis

This note deals with the scanning of femoral head slices from both normal and osteoporosis subjects using synchrotron radiation X-ray fluorescence (SRXRF) microprobe technique. The sample preparation and experimental apparatus are described in detail. The quantitative computerized tomography (QCT) of elemental distribution, such as Ca, P, K, Fe, Zn, Sr and Pb in bone slice tissue including cartilage, substantial compact and substantial spongy, is investigated. Combined with the correlation between P, K, Zn, Sr and Ca, the loss way of minerals and the physiological functions of some metal elements in bone are also discussed.

Sulfur speciation and bioaccumulation in camphor tree leaves as atmospheric sulfur indicator analyzed by synchrotron radiation XRF and XANES

Analyzing and understanding the effects of ambient pollution on plants is getting more and more attention as a topic of environmental biology.A method based on synchrotron radiation X-ray fluorescence and X-ray absorption near edge structure spectroscopy was established to analyze the sulfur concentration and speciation in mature camphor tree leaves （CTLs）,which were sampled from 5 local fields in Shanghai,China.Annual SO2 concentration,SO42-concentration in atmospheric particulate,SO42-and sulfur concentration in soil were also analyzed to explore the relationship between ambient sulfur sources and the sulfur nutrient cycling in CTLs.Total sulfur concentration in mature camphor tree leaves was 766-1704 mg/kg.The mainly detected sulfur states and their corresponding compounds were ＋6 （sulfate,include inorganic sulfate and organic sulfate）,＋5.2 （sulfonate）,＋2.2 （suloxides）,＋0.6 （thiols and thiothers）,＋0.2 （organic sulfides）.Total sulfur concentration was strongly correlated with sulfate proportion with a linear correlation coefficient up to 0.977,which suggested that sulfur accumulated in CTLs as sulfate form.Reduced sulfur compounds （organic sulfides,thiols,thioethers,sulfoxide and sulfonate） assimilation was sufficed to meet the nutrient requirement for growth at a balanced level around 526 mg/kg.The sulfate accumulation mainly caused by atmospheric sulfur pollution such as SO2 and airborne sulfate particulate instead of soil contamination.From urban to suburb place,sulfate in mature CTLs decreased as the atmospheric sulfur pollution reduced,but a dramatic increase presented near the seashore,where the marine sulfate emission and maritime activity pollution were significant.The sulfur concentration and speciation in mature CTLs effectively represented the long-term biological accumulation of atmospheric sulfur pollution in local environment.

Compositional Distribution and Growth Mode of Garnet Porphyroblasts during Deformation and Metamorphism

Although porphyroblast microstructures play an important role in structural and metamorphic studies, there are still controversies in the interpretation. The focus is how porphyroblasts grow during deformation and metamorphism. In this paper, we introduce a new approach, the Synchrotron Radiation X-Ray Fluorescence, to a hemi-quantitative interpretation of the growth mode of porphyroblasts. The analysis was done at the Beijing Synchrotron Radiation Facility. The specimens were sampled from metapelite of the Baoyintu Group, northern Urad Middle Banner, Inner Mongolia. The new method is successful for determining the microscopic distribution of trace elements in porphybroblasts. The results support the theory of deformation partition, which has been brought forth by Bell and his colleagues, and demonstrate the existence of porphyroblast growth phases and the growth mode of porphyroblasts by hemi-quantitative mineral chemical analysis. The porphyroblast grows stage by stage in the manner of the distribution of a roseleaf and is controlled by deformation. We call the growth stage of porphyroblast a growth phase.

SRXRF Experiments and Analytical Methods of Mineral Individual Fluid Inclusions

This paper focuses on the micro-beam and trace element non-destructive experiment and analytical method of mineral fluid inclusions by synchrotron radiation X-ray fluorescence （SRXRF） microprobe at Beijing Synchrotron Radiation Facility （BSRF）. The experimental instrument, measurement process and calculating method are introduced. A set of oil- and gas-containing typical mineral fluid inclusions taken from the Tazhong and Lunnan oilfields in the Tarim Basin were analyzed non-destructively. The trace element contents in the fluid inclusions may provide guidance for oil and gas exploration and development.

Sodium and potassium in the bones of penguin and skua revealed by EPR and SR-XRF technique

Penguin and skua in the maritime Antarctic have high salt loadings in the body due to almost exclusive diet consumption of marine invertebrates.However,the storage and turnover of sodium and potassium in these animals are poorly investigated.Here we determined the concentration and microscopic distribution of the two elements in the bones of penguin and skua.The average concentrations of sodium and potassium in penguin bone were comparable with that in skua bone（0.18% and 0.82% for penguin bone;0.19% and 0.76% for skua bone in dry weight）.The ratios of sodium to calcium and potassium to calcium（0.0330 and 0.0075 for penguin,0.0335 and 0.0082 for skua in average by weight） were somewhat higher than the reported ratios for terrestrial animals,indicating these marine animals＇ bone enrichment of salt.The ratios of sodium to potassium in average by weight were 6.75 and 4.65 for penguin and skua,respectively.This value is much lower compared with the bulk sea water ratio of about 27.0,implying that potassium is favorable to reside in the bone rather than sodium.Both sodium and potassium were found to significant correlation with the content of organic materials in bone based upon the intensity of native signal determined by electron paramagnetic resonance（EPR）.It was estimated that almost all of potassium is kept within the organic phases,while about 30% of sodium is stored in organic phases and the other 70% within mineral phase.The microscopic distributions of potassium in the cross-section and/or surface were revealed by synchrotron radiation Xray fluorescence（SR-XRF） technique.The ratio of potassium to calcium based upon the SR-XRF intensity counter varied considerably from the surface to the interior,and on the surface the highest concentration of potassium was observed in the middle section with decreasing amounts toward the edge.This indirectly documented that exchange of potassium between fluid and bone organic phase maybe occur.

Water Quality Monitoring of the Bezerra River （Cascavel, Brazil） Using SR-TXRF Technique

The present study aims to monitor and assess the water quality of the Bezerra River located in the Western Brazilian Parana state. For the monitoring of river waters, six samplings were established per month during one year. As indicators of the water quality, physico-chemical parameters such as water temperature, pH, turbidity, dissolved oxygen and COD （chemical oxygen demand） were chosen, as well as trace and majority element concentrations. It is noteworthy that the mean annual values of conductivity, turbidity and COD have progressively increased along the river with maximum values after the Cascavel western sewage treatment plant. Only 13 elements were found in the six collection points, but the metallic elements Cr, Mn, Fe, Cu and Zn have shown concentrations above the maximum limits recommended by Brazilian environmental legislation, suggesting the presence of highly polluting anthropogenic sources. Correlation analyses were used to determine the spatio-variability of water quality variables. The six collection sites were grouped into two clusters, with the element composition in the first cluster （sites 1, 2 and 6） being due to strong anthropogenic activities. The study of the Bezerra River water quality could help to develop municipal environmental policies and help with the management of water conservation in the Bezerra River basin.

Compositional change in human enamel irradiated with MIR free electron laser

The purpose of this study was to investigate compositional changes in human enamel irradiated with the free electron laser (FEL). The exposure on dental enamel at the wavelength of 9.64 μm was observed with the Beijing free electron laser. The distribution of elements in the irradiated or non-irradiated enamel was measured by scanning electron microscope (SEM) with energy-dispersive spectroscopy and synchrotron radiation X-ray fluorescence (SRXRF) in Beijing Synchrotron Radiation Facility (BSRF). The results showed that the P/Ca ratio in the ablation region of enamel at the maximum wavelength of infrared absorption was obviously smaller than that at the non-maximum wavelength. In the ablation region the ratios of P/Ca and Ca/Sr were smaller than those in the non-ablation region. The distributions of P, Ca and Sr in the ablation region were heterogeneous due to the element change caused by FEL irradiation.

Ore Forming Fluids of Several Gold Deposits in the Irtysh Gold Belt, Xinjiang, China

The metallogenic environment of the Irtysh gold belt in Xinjiang is studied in detail.The metallogenic geological background,metallogenic conditions and ore-controlling factors of the gold deposits in eastern,central and western regions of the metallogenic belt are compared.The metallogenic structure of the Irtysh tectonic belt has the characteristics of diverging to the west and converging to the east.Composite ore controlling by ductile shearing and magmatic activity in Irtysh gold belt result in zoned and segmented distribution of gold mineralization.Through the fluid inclusion research and H-O-S isotope analysis,the evolution regularity of gold ore-forming fluids in the region was analyzed.Synchrotron radiation X-ray fluorescence was used to analysis the concentration of metal elements in a single fluid inclusion,explaining the occurrence and migration process of Au in hydrothermal fluid.The source of ore forming minerals in western gold deposit is more closely related to magmatic activity,and the structural metamorphism of eastern gold deposit has greater influence on mineralization.Metallogenic fluids of gold deposits are characterized by metamorphic water(and magmatic water)in the early stage and mixed with meteoric water in the late stage.And the metallogenic elements are enriched in CO2 rich fluid.The Au is mainly activated,migrated and enriched with the mixed fluid of magmatic hydrothermal,metamorphic hydrothermal and atmospheric precipitation in the medium-low temperature,shallow to medium-deep environment.