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1.
A new double-sided laser heating system optimized for monochromatic X-ray diffraction at high pressure and high temperature has been developed at beamline ID27 of the European Synchrotron Radiation Facility (ESRF). The main components of this system including optimized focusing optics to produce a large and homogenous heated area, optimized mirror optics for temperature measurements and a state-of-the-art diffraction setup are described in details. Preliminary data collected at high pressure and high temperature on tungsten and iron are presented.  相似文献   

2.
Abstract

For phase transition studies, neutron powder diffraction offers a number of important advantages over x-ray based techniques, for example ab-initio structural determination. There are two distinct methods using either monochromatic angular dispersive geometry on a reactor cold source or time-of-flight energy-dispersive techniques requiring a pulsed neutron source. Both techniques offer comparable resolution but have differing advantages for high pressure studies. Recent studies illustrate the benefits of the two methods and the application of these to solve unknown crystal structures.  相似文献   

3.
Summary The Nuclear-Resonance Beamline at ESRF is dedicated to the excitation of nuclear levels by synchrotron radiation. The source of radiation and optical elements are optimized to provide an intense, highly monochromatic, collimated and stable X-ray beam of small cross-section at the M?ssbauer transition energies between 6 keV and 30 keV. The set-up of the beamline allows to perform studies in diffraction, small-angle scattering, forward scattering and incoherent scattering. Equipment is available to maintain the sample at variable temperature and magnetic field. Fast detectors and timing electronics serve to separate the delayed nuclear scattering from the ?prompt? electronic scattering and to measure the time spectra of nuclear radiation with sub-nanosecond resolution. The general layout and the parameters of the beamline are reported. Typical domains of applications are discussed and illustrated by first experimental results. Paper presented at ICAME-95, Rimini, 10–16 September 1995.  相似文献   

4.
A full‐field hard X‐ray imaging beamline (BL‐4) was designed, developed, installed and commissioned recently at the Indus‐2 synchrotron radiation source at RRCAT, Indore, India. The bending‐magnet beamline is operated in monochromatic and white beam mode. A variety of imaging techniques are implemented such as high‐resolution radiography, propagation‐ and analyzer‐based phase contrast imaging, real‐time imaging, absorption and phase contrast tomography etc. First experiments on propagation‐based phase contrast imaging and micro‐tomography are reported.  相似文献   

5.
The hard X‐ray beamline BL8 at the superconducting asymmetric wiggler at the 1.5 GeV Dortmund Electron Accelerator DELTA is described. This beamline is dedicated to X‐ray studies in the spectral range from ~1 keV to ~25 keV photon energy. The monochromator as well as the other optical components of the beamline are optimized accordingly. The endstation comprises a six‐axis diffractometer that is capable of carrying heavy loads related to non‐ambient sample environments such as, for example, ultrahigh‐vacuum systems, high‐pressure cells or liquid‐helium cryostats. X‐ray absorption spectra from several reference compounds illustrate the performance. Besides transmission measurements, fluorescence detection for dilute sample systems as well as surface‐sensitive reflection‐mode experiments have been performed. The results show that high‐quality EXAFS data can be obtained in the quick‐scanning EXAFS mode within a few seconds of acquisition time, enabling time‐resolved in situ experiments using standard beamline equipment that is permanently available. The performance of the new beamline, especially in terms of the photon flux and energy resolution, is competitive with other insertion‐device beamlines worldwide, and several sophisticated experiments including surface‐sensitive EXAFS experiments are feasible.  相似文献   

6.
The SUT‐NANOTEC‐SLRI beamline was constructed in 2012 as the flagship of the SUT‐NANOTEC‐SLRI Joint Research Facility for Synchrotron Utilization, co‐established by Suranaree University of Technology (SUT), National Nanotechnology Center (NANOTEC) and Synchrotron Light Research Institute (SLRI). It is an intermediate‐energy X‐ray absorption spectroscopy (XAS) beamline at SLRI. The beamline delivers an unfocused monochromatic X‐ray beam of tunable photon energy (1.25–10 keV). The maximum normal incident beam size is 13 mm (width) × 1 mm (height) with a photon flux of 3 × 108 to 2 × 1010 photons s?1 (100 mA)?1 varying across photon energies. Details of the beamline and XAS instrumentation are described. To demonstrate the beamline performance, K‐edge XANES spectra of MgO, Al2O3, S8, FeS, FeSO4, Cu, Cu2O and CuO, and EXAFS spectra of Cu and CuO are presented.  相似文献   

7.
The X‐ray Powder Diffraction (XPD) beamline at the National Synchrotron Light Source II is a multi‐purpose high‐energy X‐ray diffraction beamline with high throughput and high resolution. The beamline uses a sagittally bent double‐Laue crystal monochromator to provide X‐rays over a large energy range (30–70 keV). In this paper the optical design and the calculated performance of the XPD beamline are presented. The damping wiggler source is simulated by the SRW code and a filter system is designed to optimize the photon flux as well as to reduce the heat load on the first optics. The final beamline performance under two operation modes is simulated using the SHADOW program. For the first time a multi‐lamellar model is introduced and implemented in the ray tracing of the bent Laue crystal monochromator. The optimization and the optical properties of the vertical focusing mirror are also discussed. Finally, the instrumental resolution function of the XPD beamline is described in an analytical method.  相似文献   

8.
Two novel high‐temperature reactors for in situ X‐ray absorption spectroscopy (XAS) measurements in fluorescence are presented, each of them being optimized for a particular purpose. The powerful combination of these reactors with the turbo‐XAS technique used in a dispersive‐XAS beamline permits the study of commercial three‐way catalysts under realistic gas composition and temporal conditions.  相似文献   

9.
A system for stress measurement under high pressure has been developed at beamline BL04B1, SPring‐8, Japan. A Kawai‐type multi‐anvil apparatus, SPEED‐1500, was used to pressurize polycrystalline KCl to 9.9 GPa in a mechanically anisotropic cell assembly with the KCl sample sandwiched between dense Al2O3 pistons. The variation of deviatoric stress was determined from the lattice distortion measured using two‐dimensional X‐ray diffraction with monochromatic synchrotron X‐rays. The low‐pressure B1 phase transformed to the high‐pressure polymorph B2 during compression. The deviatoric stress increased with increasing pressure in both the B1 and B2 phases except for the two‐phase‐coexisting region at a pressure of 2–3 GPa. This new system provides one of the technical foundations for conducting precise rheological measurements at conditions of the Earth's lower mantle.  相似文献   

10.
As an increasingly important structural‐characterization technique, grazing‐incidence X‐ray scattering (GIXS) has found wide applications for in situ and real‐time studies of nanostructures and nanocomposites at surfaces and interfaces. A dedicated beamline has been designed, constructed and optimized at beamline 8‐ID‐E at the Advanced Photon Source for high‐resolution and coherent GIXS experiments. The effectiveness and applicability of the beamline and the scattering techniques have been demonstrated by a host of experiments including reflectivity, grazing‐incidence static and kinetic scattering, and coherent surface X‐ray photon correlation spectroscopy. The applicable systems that can be studied at 8‐ID‐E include liquid surfaces and nanostructured thin films.  相似文献   

11.
The design of a 57Fe Synchrotron Mössbauer Source (SMS) for energy‐domain Mössbauer spectroscopy using synchrotron radiation at the Nuclear Resonance beamline (ID18) at the European Synchrotron Radiation Facility is described. The SMS is based on a nuclear resonant monochromator employing pure nuclear reflections of an iron borate (57FeBO3) crystal. The source provides 57Fe resonant radiation at 14.4 keV within a bandwidth of 15 neV which is tunable in energy over a range of about ±0.6 µeV. In contrast to radioactive sources, the beam of γ‐radiation emitted by the SMS is almost fully resonant and fully polarized, has high brilliance and can be focused to a 10 µm × 5 µm spot size. Applications include, among others, the study of very small samples under extreme conditions, for example at ultrahigh pressure or combined high pressure and high temperature, and thin films under ultrahigh vacuum. The small cross section of the beam and its high intensity allow for rapid collection of Mössbauer data. For example, the measuring time of a spectrum for a sample in a diamond anvil cell at ~100 GPa is around 10 min, whereas such an experiment with a radioactive point source would take more than one week and the data quality would be considerably less. The SMS is optimized for highest intensity and best energy resolution, which is achieved by collimation of the incident synchrotron radiation beam and thus illumination of the high‐quality iron borate crystal within a narrow angular range around an optimal position of the rocking curve. The SMS is permanently located in an optics hutch and is operational immediately after moving it into the incident beam. The SMS is an in‐line monochromator, i.e. the beam emitted by the SMS is directed almost exactly along the incident synchrotron radiation beam. Thus, the SMS can be easily utilized with all existing sample environments in the experimental hutches of the beamline. Owing to a very strong suppression of electronic scattering for pure nuclear reflections (~10?9), SMS operation does not required any gating of the prompt electronic scattering. Thus, the SMS can be utilized in any mode of storage ring operation.  相似文献   

12.
Information on the structural evolution of materials under high pressure is of great importance for understanding the properties of materials exhibited under high pressure. High‐pressure powder diffraction is widely used to investigate the structure evolution of materials at such pressure. Unfortunately, powder diffraction data are usually insufficient for retrieving the atomic structures, with high‐pressure single‐crystal diffraction being more desirable for such a purpose. Here, a high‐pressure single‐crystal diffraction experimental system developed recently at beamline 4W2 of Beijing Synchrotron Radiation Facility (BSRF) is reported. The design and operation of this system are described with emphasis on special measures taken to allow for the special circumstance of high‐pressure single‐crystal diffraction. As an illustration, a series of diffraction datasets were collected on a single crystal of LaB6 using this system under various pressures (from ambient pressure to 39.1 GPa). The quality of the datasets was found to be sufficient for structure solution and subsequent refinement.  相似文献   

13.
Abstract

It is widely recognized that relevant new chemistry is being discovered by applying high pressures. The study of the equation of state, pressure-induced phase transitions, reactivity, etc., of molecular systems are topics of increasing interest in high pressure science. This paper compiles recent studies performed by the author on molecular systems at high pressures. This includes, on the theoretical side, a reference to a universal model of EOS for both liquids and solids at high pressure. Several experiments performed by the author are also discussed; among others, a high pressure polymerization of carbon monoxide, the design of an anvil cell system developed in our laboratory, introducing an alternative Raman pressure scale when sapphires are mounted as anvils (SAC configuration) and, finally, several actual SAC experiments are presented, including examples of phase transitions and reactivity at high pressure on double and triple bonded molecular systems.  相似文献   

14.
The Nuclear Resonance Beamline at ESRF is dedicated to the excitation of nuclear levels by synchrotron radiation. The sources of radiation and optical elements are optimized to provide an intense, highly monochromatic, collimated and stable X-ray beam of small cross-section at the Mössbauer transition energies between 6 and 30 keV. The set-up of the beamline allows to perform studies in diffraction, small angle scattering, forward scattering and incoherent scattering. Equipment is available to maintain the sample at variable temperature and magnetic field. Fast detectors and timing electronics serve to separate the delayed nuclear scattering from the prompt electronic scattering and to measure the time spectra of nuclear radiation with sub-nanosecond resolution. The general lay-out and the parameters of the beamline are reported. Typical domains of applications are discussed and illustrated by first experimental results.  相似文献   

15.
X‐Treme is a soft X‐ray beamline recently built in the Swiss Light Source at the Paul Scherrer Institut in collaboration with École Polytechnique Fédérale de Lausanne. The beamline is dedicated to polarization‐dependent X‐ray absorption spectroscopy at high magnetic fields and low temperature. The source is an elliptically polarizing undulator. The end‐station has a superconducting 7 T–2 T vector magnet, with sample temperature down to 2 K and is equipped with an in situ sample preparation system for surface science. The beamline commissioning measurements, which show a resolving power of 8000 and a maximum flux at the sample of 4.7 × 1012 photons s?1, are presented. Scientific examples showing X‐ray magnetic circular and X‐ray magnetic linear dichroism measurements are also presented.  相似文献   

16.
This work presents the new Metrology beamline at the SOLEIL synchrotron facility and a first attempt to quantitative measurements of mass attenuation coefficients for Ag and Sn performed on the hard X‐ray branch. We first describe the beamline itself and the characterization performed of the unfocused monochromatic beam running mode. We performed a first experimental measurement of mass attenuation coefficients in the range 3.5 ≤ E ≤ 28 keV and we also derived the K‐absorption and L‐absorption jump ratios. The results are compared with theoretical values as well as with other experimental data and agree well with previous published values. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

17.
Abstract

In the second phase construction of further insertion devices, beamlines and experimental stations at the Beijing Synchrotron Radiation Facility, a dedicated high-pressure x-ray diffraction station will be constructed. We outline the synchrotron radiation source, beamline optics and high-pressure x-ray diffraction apparatus. This facility is planned to operate for users in 1994.

Presented at the IUCr Workshop on ‘Synchrotron Radiation Instrumentation for High Pressure Crystallography’, Daresbury Laboratory 20-21 July 1991  相似文献   

18.
北京同步辐射3B3中能束线X射线探测系统性能研究   总被引:7,自引:0,他引:7       下载免费PDF全文
北京同步辐射装置(BSRF)的3B3中能束线的应用,在国内首次提供了一台能区在2—6keV范围、性能优良的单色X射线光源. 对光源的性能进行了研究,并完成了X射线探测器(XRD)灵敏度、滤片厚度、多种晶体衍射效率以及成像板能量响应等指标的标定.XRD标定的相对不确定度好于7%,滤片厚度的不确定度小于3.6%. 关键词: 中能X射线 同步辐射 标定  相似文献   

19.
A system for deformation experiments under high pressure using a deformation cubic apparatus, with monochromatic synchrotron radiation, has been developed at beamline AR-NE7A, Photon Factory, KEK High Energy Accelerator Research Organization, Japan. We have conducted deformation experiments of fayalite using this new system at pressures up to 5 GPa and temperatures up to 1073 K, and successfully conducted the stress and strain measurements during the deformation.  相似文献   

20.
ABSTRACT

We have developed a technique for neutron diffraction experiments at pressures up to 40?GPa using a Paris-Edinburgh press at the PLANET beamline in J-PARC. To increase the maximum accessible pressure, the diameter of the dimple for sample chamber at the top of the sintered diamond anvils is sequentially reduced from 4.0?mm to 1.0?mm. As a result, the maximum pressure increased and finally reached 40?GPa. By combining this technique with the beam optics which defines the gauge volume, diffraction patterns sufficient for full-structure refinements are obtainable at such pressures.  相似文献   

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