Synchrotron instrumentation

We have built a novel laboratory USXA spectrometer and measured the Li-K XANES spectra of lithium halides. The measured spectra were compared with those of the synchrotron instrument. The results indicated the Li-K XANES spectra can be measured by using this spectrometer by the same quality as the synchrotron instrument. The Li-K XANES spectra of lithium chloride and lithium bromide were analyzed by using the DV-Xa calculations. The obtained XANES spectra could be assigned by using [Li13X6]7 cluster model. 

An IP reader has been constructed in Hamburg and is now used routinely on the X-ll and X-31 synchrotron instruments of EMBL for macromolecular crystal data collection. More recently, Rigaku have announced a dual IP scanner system for macromolecular crystallography. 

The analysis was performed by XRF method with SR. SRXRF is an instrumental, multielemental, non-destructive analytical method using synchrotron radiation as primary excitation source. The fluorescence radiation was measured on the XRF beam-line of VEPP-3 (E=2 GeV, 1=100 mA), Institute of Nuclear Physics, Novosibirsk, Russia. For quality control were used international reference standards. 

No commercial instruments specifically for UPS usually an add-on to XPS (incremental cost " 30,000) or done using a synchrotron facility as the photon source... 

Without exception, the highest quality EXAFS data are acquired at synchrotron radiation facilities. There are 20 operational facilities throughout the world. Each has unique instrumentation The interested user is encouraged to contact the facil-... 

The major advantage of time-resolved X-ray techniques, as compared to optical spectroscopy, is that their wavelength X as well as the pulse duration r can be chosen to fit the atomic scales. This is not the case for optical spectroscopy, where the wavelength X exceeds interatomic distances by three orders of magnitude at least. Unfortunately, X-ray techniques also have their drawbacks. They require large-scale instruments such as the synchrotron. Even much larger... 

The Mo K-edge EXAFS spectra for the catalysts and reference compounds (MoSj and NajMoOJ were measured on the BL-lOB instruments of the Photon Factory at the National Laboratory for High Energy Physics by using a synchrotron radiation. The EXAFS spectra were obtained at room temperature without exposing the sample to air by using an in situ EXAFS cell with Kapton windows [12]. Data analysis was earned out assuming a plane wave approximation. 

In this chapter, we present the principles of conventional Mossbauer spectrometers with radioactive isotopes as the light source Mossbauer experiments with synchrotron radiation are discussed in Chap. 9 including technical principles. Since complete spectrometers, suitable for virtually all the common isotopes, have been commercially available for many years, we refrain from presenting technical details like electronic circuits. We are concerned here with the functional components of a spectrometer, their interaction and synchronization, the different operation modes and proper tuning of the instrument. We discuss the properties of radioactive y-sources to understand the requirements of an efficient y-counting system, and finally we deal with sample preparation and the optimization of Mossbauer absorbers. For further reading on spectrometers and their technical details, we refer to the review articles [1-3]. 

The progress achieved is closely linked to the development of both powerful detectors and brilliant X-ray sources (synchrotron radiation, rotating anode). Such point-focus equipment has replaced older slit-focus equipment (Kratky camera, Rigaku-Denki camera) in many laboratories, and the next step of instrumental progress is already discernible. With the X-ray free electron laser (XFEL) it will become possible to study very fast processes like the structure relaxation of elastomers after the removal of mechanical load. 

The usability of the various available machines, in particular in regard to time-resolved measurements, is proportional to the flux that they are able to shine on the sample. Table 4.1 shows typical data. Modern laboratory instrumentation (rotating anode) is approaching the performance of older synchrotron light sources. 

X-ray Instrumentation. All experiments were performed at the Cornell High Energy Synchrotron Source (CHESS) operated at 5.8 GeV (Stations A-3, B and C-2). Monochromatic radiation was obtained with a Si (220) double crystal monochromator. In order to eliminate higher harmonics, 50% detunning was typically employed. ... 

Harbottle, G., Gordon, B. M., and Jones, K.W. (1986). Use of synchrotron radiation in archaeometry. Nuclear Instruments and Methods in Physics Research B 14 116-122. 

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