Response of shortgrass plains vegetation to gamma radiation—ii. Short-term seasonal irradiation

1973 ◽  
Vol 13 (6) ◽  
pp. 343-353 ◽  
Author(s):  
L. Fraley ◽  
F.W. Whicker
2020 ◽  
Vol 180 ◽  
pp. 108841 ◽  
Author(s):  
Shaodan Huang ◽  
Eric Garshick ◽  
Carolina L.Z. Vieira ◽  
Stephanie T. Grady ◽  
Joel D. Schwartz ◽  
...  

Author(s):  
SMJ Mortazavi ◽  
A Niroomand-Rad ◽  
P Roshan-Shomal ◽  
SMT Razavi-Toosi ◽  
M Mossayeb-Zadeh ◽  
...  

2019 ◽  
Vol 175 ◽  
pp. 221-227 ◽  
Author(s):  
Carolina L.Z. Vieira ◽  
Petros Koutrakis ◽  
Shaodan Huang ◽  
Stephanie Grady ◽  
Jaime E. Hart ◽  
...  

2021 ◽  
Vol 14 (1) ◽  
pp. 75-85
Author(s):  
V. Yu. Golikov ◽  
L. A. Chipiga ◽  
A. V. Vodovatov ◽  
M. Ya. Smolyarchuk

The paper presents the data that allow calculate the attenuation factors in lead, tungsten and concrete of various thicknesses or the thickness of shielding made of these materials for a given attenuation factor for the spectra of gamma radiation of 131I and 177Lu radionuclides. Using these data the effectiveness of the protection of supporting equipment (portable containers, shielded syringes, etc.) and the possible doses of external radiation of medical personnel in the radionuclide therapy department were calculated. It is shown that there are short-term operations in the production process when a radiation source (container with a capsule with activity, syringe with activity), being near the body of a medical worker, creates a significant dose rate. For this reason the annual individual dose of external exposure of a medical worker can approach or exceed 1/3 of the dose limit. Calculation of the attenuation of 131I gamma radiation by stationary shield showed that the thickness of walls and floors made of concrete 200 – 400 mm will ensure that the permissible values of the dose rates of gamma radiation in the air do not exceed at annual turnover of activity in the radionuclide therapy department of ~ 3.3 · 1012 Bq.


2014 ◽  
Vol 354 ◽  
pp. 49-66
Author(s):  
Nilson Casimiro Pereira ◽  
Mauro Cesar Terence ◽  
D.F. Bruzadin ◽  
G.J.M. Fechine ◽  
Leila F. de Miranda ◽  
...  

As the polypropylene resin of high consumption, has as a consequence, the same feature among the resins most discarded after use. This generates high amount of waste in landfills, causing environmental problems, because the polypropylene presents difficulty in the short term, degradation by micro-organisms in the trash. Thus, this resin recycling proposals are always welcome, raising the possibility of reuse, and reducing the concentration of the landfills, thereby helping to minimize the negative effects of its disposal on the environment. Some manufacturers of rubber products, using as raw materials EPDM, report that are discarded after processing the waste, largely in landfills. Thus, the proposed reuse of byproduct, also will not contribute to the degradation of the environment. The aim of this work was to produce compositions (mixtures) with different concentrations of polypropylene and EPDM recycled materials, and evaluate the effect of ultraviolet and gamma radiation, rheological properties, thermal, mechanical and morphological, of the composites. The compounds obtained showed that waste rubber modified thermoplastic properties of polypropylene when irradiated by both UV radiation, such as gamma radiation.Comparing the hardness and impact tests, it was observed that the values ​​decreased with respect to the material not irradiated (UV or gamma). This effect is due mainly to the presence of the EPDM rubber, because the PP when subjected to gamma radiation or UV at low doses has an increase in mechanical properties.


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