scholarly journals Radiation therapy with neutrons and hydrons of the liver region using the MCNP code: المعالجة الاشعاعية بالنترونات والهدرونات لمنطقة الكبد باستخدام الكود MCNP

2021 ◽  
Vol 5 (4) ◽  
pp. 141-131
Author(s):  
Lara Kamal Jarouj, Anis Bilal, Nikola Abo Issa Lara Kamal Jarouj, Anis Bilal, Nikola Abo Issa
Keyword(s):  
Radiation Therapy ◽  
Radiation Dose ◽  
3D Model ◽  
High Energy ◽  
Radiation Doses ◽  
High Energy Radiation ◽  
Energy Radiation ◽  
Liver Region ◽  
High Depth ◽  
Tumor Area

CT images were read and a 3D model of the tumor was created in the liver area, Then the values ​​of the radiation dose in terms of the depth resulting from (photons, neutrons and protons) were estimated and studied using the code (MCNP) after entering the data into it. The value of the radiation dose in terms of depth and curvature in photons, neutrons and protons radiation therapy was studied, from our findings in the research we note that protons are the best option for radiation therapy for high-depth liver cancer of photons and neutrons due to the lower dose at entry compared to the dose absorbed in the tumor area and its ability to deliver a greater amount of dose of neutrons and photons to the tumor area. We note that the values reached are acceptable for the treatment of tumors at a depth close to the surface. As for a large-depth tumor, it is necessary to increase high-energy radiation doses deep in the tumor area by accelerating proton therapy to protect natural organs from high-energy radiation doses.

scholarly journals Neutron spectra and dose equivalents calculated in tissue for high-energy radiation therapy

2009 ◽  
Vol 36 (4) ◽  
pp. 1244-1250 ◽  
Author(s):  
Stephen F. Kry ◽  
Rebecca M. Howell ◽  
Mohammad Salehpour ◽  
David S. Followill
Keyword(s):  
Radiation Therapy ◽  
High Energy ◽  
High Energy Radiation ◽  
Energy Radiation ◽  
Neutron Spectra

A doorless entry system for high-energy radiation therapy rooms

1998 ◽  
Vol 25 (2) ◽  
pp. 199-201 ◽  
Author(s):  
D. J. Dawson ◽  
W. W. F. M. Wissing ◽  
R. E. Tonks
Keyword(s):  
Radiation Therapy ◽  
High Energy ◽  
High Energy Radiation ◽  
Energy Radiation

scholarly journals Fibrosarcoma after high energy radiation therapy for pituitary adenoma

1980 ◽  
Vol 135 (5) ◽  
pp. 1087-1090 ◽  
Author(s):  
WH Martin ◽  
WS Cail ◽  
JL Morris ◽  
WC Constable
Keyword(s):  
Radiation Therapy ◽  
Pituitary Adenoma ◽  
High Energy ◽  
High Energy Radiation ◽  
Energy Radiation

Dosimetry: High-Energy Radiation Therapy

Science ◽  
1967 ◽  
Vol 158 (3807) ◽  
pp. 1499-1508
Author(s):  
L. H. Lanzl ◽  
J. S. Laughlin
Keyword(s):  
Radiation Therapy ◽  
High Energy ◽  
High Energy Radiation ◽  
Energy Radiation

Crosslinking and Radiation Effects in Some Natural and Synthetic Rubbers

1957 ◽  
Vol 30 (1) ◽  
pp. 27-41 ◽  
Author(s):  
A. Charlesby ◽  
D. Groves
Keyword(s):  
Radiation Dose ◽  
Natural Rubber ◽  
Radiation Effects ◽  
Main Chain ◽  
High Energy ◽  
High Energy Radiation ◽  
Energy Radiation ◽  
Physical Technique ◽  
Chemical Agents ◽  
Natural And Synthetic

Abstract When subjected to atomic energy radiation certain polymers crosslink, a process which is equivalent to vulcanization, but occurs without the admixture of extraneous chemical agents. Other polymers degrade by main chain fracture, a process which occurs at random throughout the molecule, and is different from thermal or ultraviolet degradation. Methods available for detecting crosslinking in irradiated polymers, include those based on solubility and swelling which have been used to study the effect of high energy radiation on a number of natural and synthetic rubbers. The polymers investigated include natural rubber, polychloroprene, polyisobutylene, polybutadiene, and thioplasts, as well as some copolymers. The results show the degree of crosslinking to be proportional to radiation dose, and to be reduced by the presence of styrene or acrylonitrile units in copolymers. Possible applications of this physical technique of linking molecules are discussed briefly.

Radiation-induced racemization and amplification of chirality: implications for comets and meteorites

2007 ◽  
Vol 6 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Franco Cataldo
Keyword(s):  
Cosmic Rays ◽  
Radiation Dose ◽  
Optical Activity ◽  
High Energy ◽  
Chiral Molecules ◽  
Radiation Processing ◽  
High Energy Radiation ◽  
Energy Radiation ◽  
Naturally Occurring ◽  
Radiation Induced

The action of high-energy radiation on prebiotic chiral molecules plays against the preservation of chirality. Chiral molecules incorporated in comets and meteorites are bombarded for billions of years by cosmic rays and by the high-energy radiation due to the decay of naturally occurring radionuclides. The action of cosmic rays on the surface of comets and meteorites causes the complete radiation processing of the surface of these bodies, but at depths of 20 m or so the cosmic rays are completely shielded and the radiation should derive only from the decay of radionuclides. In 4.6×109 yr the radiation dose supplied by the radionuclide decay to the organic molecules present inside the cometary or meteoritic body is equivalent to 14000 kGy. Our studies on the radiolysis of a series of naturally occurring chiral molecules, the terpenes, have shown that although all undergo the radioracemization reaction, the extent of radioracemization is such that a significant fraction of chiral excess and chiral molecules can survive a radiation dose equivalent to 14000 kGy. A unique exception is represented by the terpene β-(−)-pinene which, instead of the expected radioracemization reaction, undergoes a radiation-induced polymerization. The resulting poly-β-pinene, having an highly ordered supramolecular structure, displays an optical activity which is 1.7 times higher than the starting monomer. Thus, in this specific case, the optical activity is not reduced but enhanced by the action of radiation and remains locked into a polymer which displays a considerable radiation resistance and may act as a chiral template and as a chiral surface for prebiotic chemistry.

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