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Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Ming Wang, Jinxing Zheng, Yuntao Song, Xianhu Zeng, Ming Li, Wuquan Zhang, Pengyu Wang, Junsong Shen
Nuclear Technology | Volume 206 | Number 5 | May 2020 | Pages 779-790
Technical Paper | doi.org/10.1080/00295450.2019.1670011
Articles are hosted by Taylor and Francis Online.
The superconducting isochronous cyclotron SC200 for proton therapy is under development in Hefei, and the active scanning method has been selected as the beam delivery technology. To reduce energy loss and transverse scattering of the proton beam, a gas chamber in the pencil beam scanning (PBS) nozzle has been designed to shorten the length of the air segment. To determine whether using a helium filling gas or vacuum is the most suitable for the SC200 PBS nozzle, the beam size and the energy loss at the isocenter and the dose distribution in the water phantom are compared using the TOol for PArticle Simulation (TOPAS) code. The results show that using the helium filling gas resulted in scattering and energy loss of the proton beam compared with using vacuum, but these effects were minimal. Considering the disadvantages of the engineering problems of creating a vacuum chamber, helium was selected as the filling gas for the PBS nozzle chamber. Moreover, the following parameters were analyzed and optimized: gas pressure, gas purity, and film thickness of the chamber. When the helium pressure was below 1.1 atm and the air proportion was less than 5%, the beam size at the lowest energy of the proton beam at the isocenter was lower than 8 mm, meeting the clinical requirements.