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Division Spotlight
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.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
Renato Yoichi Ribeiro Kuramoto, Adimir dos Santos, Rogario Jerez, Ricardo Diniz
Nuclear Science and Engineering | Volume 158 | Number 3 | March 2008 | Pages 272-283
Technical Paper | doi.org/10.13182/NSE06-120
Articles are hosted by Taylor and Francis Online.
A new method for absolute measurement of the effective delayed neutron fraction eff based on Rossi- experiments and the two-region model was developed at the IPEN/MB-01 Research Reactor facility. In contrast with other techniques such as the slope method, the Nelson-number method, and the 252Cf-source method, the main advantage of this new methodology is to obtain the effective delayed neutron parameters in a purely experimental way, eliminating all parameters that are difficult to measure or calculate. In this way, Rossi- experiments for validation of this method were performed at the IPEN/MB-01 facility, and with the use of the present approach, eff was measured with a 1.46% uncertainty. In addition, the prompt neutron generation time and other parameters were also obtained in an absolute experimental way. In general, the final results agree well with values from frequency analysis experiments. Comparison of theory and experiment reveals that JENDL-3.3 shows deviation for eff lower than 1%, which meets the desired accuracy for the theoretical determination of this parameter. This work supports the reduction of the 235U thermal yield, as proposed by Okajima and Sakurai.