Abstract：
:The amount of silica in the human lung may be estimated by measurement of silicon using in vivo neutron activation analysis. A pulsed, fast neutron beam, produced with a 2 MV Van de Graaff generator using the 2H + 2H reaction, was used to irradiate a Si-doped chest phantom in order to determine minimum detection limits (MDL). Two 'in-beam' nuclear reactions on Si were studied; prompt fast neutron inelastic scatter 28Si (n,n' gamma)28Si reaction was measured during the beam burst and the slow neutron prompt capture reaction was measured between the fast neutron bursts. Although the latter reaction appeared less favourable due to neutron cross section and measurement efficiency considerations, it yielded an MDL of 1.8 g compared with 2.3 g for the 28Si(n,n' gamma)28Si reaction. A comparison was made with a 252Cf neutron irradiation system where a Si MDL of 6.3 g was obtained using the slow neutron capture reaction. The Van de Graaff system permits 'exposed' Si lung burdens to be measured but not normal levels. Improved measurement sensitivity may be achieved by reduction of high counting-rate losses and high background radiation.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Kacperek A,Ryde SJ,Evans CJ,Dutton J,Morgan WD,Sivyer Adoi
10.1088/0031-9155/38/6/004subject
Has Abstractpub_date
1993-06-01 00:00:00pages
689-98issue
6eissn
0031-9155issn
1361-6560journal_volume
38pub_type
杂志文章abstract：:Quantification in cardiac mouse positron emission tomography (PET) imaging is limited by the imaging spatial resolution. Spillover of left ventricle (LV) myocardial activity into adjacent organs results in partial volume (PV) losses leading to underestimation of myocardial activity. A PV correction method was develope...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/57/13/4309
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journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/61/3/1309
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journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/60/2/473
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journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/50/12/012
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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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journal_title：Physics in medicine and biology
pub_type： 临床试验,杂志文章
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journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/45/12/310
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journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/35/5/006
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journal_title：Physics in medicine and biology
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journal_title：Physics in medicine and biology
pub_type： 临床试验,杂志文章
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更新日期：2005-02-21 00:00:00
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journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/61/22/7881
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journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/1361-6560/aaa3af
更新日期：2018-02-02 00:00:00
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journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/1361-6560/ab1c37
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journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/26/1/011
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journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/27/1/011
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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
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journal_title：Physics in medicine and biology
pub_type： 杂志文章
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更新日期：2004-08-21 00:00:00
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