Thermoforming Plastic in Lead Shield Construction

1989 ◽  
Vol 14 (3) ◽  
pp. 219-221
Author(s):  
M.E. Abrahams ◽  
C.H. Chow ◽  
M.D. Loyd
Keyword(s):  
Radiocarbon ◽  
1967 ◽  
Vol 9 ◽  
pp. 257-260
Author(s):  
H. Willkomm ◽  
H. Erlenkeuser

Most of the measurements reported here have been obtained with the 4.5-L CO2 counter previously described (Kiel I; Erlenkeuser, 1965). A few samples have been dated with a 3-L proportional counter. The copper counter is surrounded by 28 GM counters in the form of a double ring. The total assembly is shielded by 10 cm of old lead. Neither an inner lead shield between counter and anticoincidence ring nor screening of sensitive volume by a quartz tube-as in the 4.5-L counter-has been used. Background of the small counter is 17.20 cpm or The 0.95 x NBS value is 9.5 cpm at 400 torr. Within statistical error background does not depend on atmospheric pressure. The 3-L counter is placed under a concrete wall, 2.5 m in length and 9.4 m in height.


2020 ◽  
Vol 188 (4) ◽  
pp. 464-469 ◽  
Author(s):  
Nika Zalokar ◽  
Nejc Mekiš

Abstract This study aimed to investigate the dose to the breasts during head computed tomography (CT) if lead shielding is used. The study was performed in two major hospitals using helical and axial protocols on an anthropomorphic phantom. Measurements were performed with and without the use of a lead shield of 0.5 mm equivalent density. The results showed a significant decrease in dose with the lead shielding in both hospitals. During the helical protocol, the use of shielding significantly reduced the dose by 96% in Hospital A and 82% in Hospital B. The dose reduction during axial protocol was also significant: 95% in Hospital A and 86% in Hospital B with lead shielding. Considering the significant dose reduction of 82% up to 96% during this study, we highly recommend the shielding of breasts regardless of the protocol used during head CT examinations.


2020 ◽  
Vol 20 (10) ◽  
pp. 1685-1691
Author(s):  
Guy Guenthner ◽  
Alexander Eddy ◽  
Jonathan Sembrano ◽  
David W. Polly ◽  
Christopher T. Martin

2004 ◽  
Vol 16 (3) ◽  
pp. 195-198 ◽  
Author(s):  
Kazuhiro Yasuda ◽  
Koichi Ishikawa ◽  
Kazuya Sonoda ◽  
Masafumi Inomata ◽  
Norio Shiraishi ◽  
...  

1986 ◽  
Vol 62 (6) ◽  
pp. 732-736 ◽  
Author(s):  
Israel Kaffe ◽  
Mark M. Littner ◽  
Tuvia Shlezinger ◽  
Pnina Segal

2008 ◽  
Vol 67 (5) ◽  
pp. AB234
Author(s):  
Toshio Kurihara ◽  
Takao Itoi ◽  
Atsushi Sofuni ◽  
Fumihide Itokawa ◽  
Shujiro Tsuji ◽  
...  

Radiocarbon ◽  
1984 ◽  
Vol 26 (2) ◽  
pp. 185-195 ◽  
Author(s):  
Reiner Protsch ◽  
Bernhard Weninger

Facilities for radiocarbon dating were established at the University of Frankfurt/Main in the Institute of Anthropology. The Radiocarbon Laboratory provides assistance to the Amino-Acid-Dating Laboratory. This list reports on 14C dates measured up to September 1983.The laboratory is installed in the basement of a three-story building and is equipped with a 2L copper proportional counter filled to 1013 mbar with purified CO2. The counter is protected against cosmic and surrounding radiation by a 3.5 ton lead shield and a copper multiwire anticoincidence ring-counter flushed with purified 90Ar/10CH4. Electronics are of the commercial NIM type. Charcoal and wood samples are treated by standard acid-alkali-acid methods. Bone samples are treated according to the collagen methods described by Berger, Horney, and Libby (1964), Longin (1971), Protsch (1972; 1975), and Protsch and Berger (1973).


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