| 摘要 |
1366357 Neutron sources SCHLUMBERGER INLAND SERVICES Inc 20 Aug 1971 [21 Aug 1970] 39174/71 Heading G6P [Also in Division G1] In borehole logging apparatus, higher and lower energy neutron sources are utilized in order to obtain measurements corrected for errors produced by scattering in the mudcake (see Division G1). The higher (4 Mev.) energy source may be a mixture of beryllium and plutonium 238, or 239, enclosed in a copper or steel shielding 20. The lower energy source may be of plutoniumlithium emitting 240 KeV neutrons. The sources may be combined in the same capsule, e.g. as a mixture of high and low energy. emitters, or as separate materials segregated by a partition, Fig. 4. |
