Abstract：
:Nuclear emulsions of the Ilford K series, exposed to X-rays from 15 to 150 kVp and systematically underdeveloped, exhibit supralinear blackness--exposure curves ranging from 1- to 4-hit in character, and whose shape is the same at all excitation voltages. Processing can be so adjusted that the curve shape is well represented by the alpha--beta model, and matches an experimental dose--response curve obtained with hamster cells after irradiation with gamma rays. The effective grain size of these emulsions is 1.3 micron when normalised to unit density material for comparison with the radiation sensitive elements of biological cells. With fractionated exposures, response curves which mimic Elkind recovery are produced.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Katz R,Pennington ECdoi
10.1088/0031-9155/23/6/007subject
Has Abstractpub_date
1978-11-01 00:00:00pages
1115-23issue
6eissn
0031-9155issn
1361-6560journal_volume
23pub_type
杂志文章abstract：:Using Cherenkov radiation in positron emission tomography (PET) has the potential to improve the time of flight (TOF) resolution and reduce the cost of detectors. In previous studies promising TOF results were achieved when lead fluoride (PbF2) crystals were used instead of a scintillator. In this work, a whole-body P...
journal_title：Physics in medicine and biology
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journal_title：Physics in medicine and biology
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journal_title：Physics in medicine and biology
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journal_title：Physics in medicine and biology
pub_type： 杂志文章
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pub_type： 杂志文章
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