Detector for X-rays

Lead sesquioxide is used as an oxidation catalyst for carbon monoxide ia exhaust gases (44,45) (see Exhaust control), as a catalyst for the preparation of lactams (46) (see Antibiotics, P-lactams), ia the manufacture of high purity diamonds (47) (see Carbon, diamond-natural), ia fireproofing compositions for poly(ethylene terephthalate) plastics (48), ia radiation detectors for x-rays and nuclear particles (49), and ia vulcanization accelerators for neoprene mbber (50). 

Fig. 3. Photon spectmm, measured by using a planar Ge detector for x-rays emitted in the radioactive P-decay of...

CdS and CdSe are also useful phosphors. CdTe is a semiconductor used as a detector for X-rays and y-rays, ° and mercury cadmium tellurideriri has found widespread (particularly military) use as an ir detector for thermal imaging. 

The advent of CCD detectors for X-ray diffraction experiments has raised the possibility of obtaining charge density data sets in a much reduced time compared to that required with traditional point detectors. This opens the door to many more studies and, in particular, comparative studies. In addition, the length of data collection no longer scales with the size of the problem, thus the size of tractable studies has certainly increased but the limit remains unknown. Before embracing this new technology, it is necessary to evaluate the quality of the data obtained and the possible new sources of error. The details of the work summarized below has either been published or submitted for publication elsewhere [1-3]. 

Cork, C., Hamlin, R., Vernon, W. and Xuong, N. H. (1975). Xenon-fhled multiwire area detector for X-ray diffraction. Acta Crystallogr. A 31, 702-703. 

Archaeobacteria 7, 815 Area detector for X-rays 134 Arg-Gly-Asp (RGD) sequence 408 Arginase 888... 

Great promise also lies in the further development of solid-state pixel detectors for X-ray imaging. Small versions of this detector type are now being used in several industrial and medical imaging applications. However, the technology is relatively immature and requires significant improvement to make it suitable for use in advanced research applications. Another important need is the... 

Milch, J. Slow scan sit detector for x-ray-diffraction studies using synchrotron radiation. IEEE Trans. Nucl. Sci. 1979, NS-26, 338. 

Gabriel A, Dupont Y (1972) A position sensitive proportional detector for X-ray crystallography. Rev scient Instrum 43 1600... 

FIGURE 12-12 Vertical cross section of a lilhium-drifted silicon detector for X-rays and radiation from radioactive sources. 

Three types of radiation detectors are in common use the gas-ionization detector, the scintillation detector, and the solid-state (or semiconductor) detector. Generally, the type used depends on the specific application. Gas-ionization detectors are commonly used for inexpensive detection of charged particles, scintillation detectors for beta- and gamma-ray detection, and solid-state detectors for x-ray and gamma-ray detection. The operation and properties of these detectors will be briefly described. 

Niki, M. 2006. Scintillation detectors for x-rays. Measurement Science and Technology 17 R37-R54. 

CASCADE SUMMING See True Coincidence Summing. CdTe Cadmium Telluride A semiconductor detector for X rays and low energy gamma-rays. Good resolution but low efficiency due to small size. 

M. Niki, Scintillation Detectors for X-Rays, Meas. Sci. Technoi, 17, R37-R54(2006). 

Dupont Y, Gabriel A, Chabre M, Bulik-Krzywicki T, Schecter E. Use of a new detector for X-ray diffraction and kinetics of the ordering of the lipids in E. coli membranes and models. Nature 1972 238 331-333. 

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