ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
Meeting Spotlight
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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!
Latest Magazine Issues
Jan 2025
Jul 2024
Latest Journal Issues
Nuclear Science and Engineering
February 2025
Nuclear Technology
Fusion Science and Technology
Latest News
How to talk about nuclear
In your career as a professional in the nuclear community, chances are you will, at some point, be asked (or volunteer) to talk to at least one layperson about the technology you know and love. You might even be asked to present to a whole group of nonnuclear folks, perhaps as a pitch to some company tangential to your company’s business. So, without further ado, let me give you some pointers on the best way to approach this important and surprisingly complicated task.
R. C. Lloyd, S. R. Bierman, E. D. Clayton
Nuclear Science and Engineering | Volume 50 | Number 2 | February 1973 | Pages 127-134
Technical Paper | doi.org/10.13182/NSE73-A23236
Articles are hosted by Taylor and Francis Online.
Experimental criticality data on borated raschig rings in plutonium nitrate solutions are presented for use in establishing criticality safety limits and in verifying calculational methods for these type systems. The data cover the concentration range between 63- and 412-g Pu/liter for borosilicate-glass raschig rings containing 0.5 and 4.0 wt% boron, and stainless-steel raschig rings containing 1 wt% boron.Criticality was possible in all three experimental vessels used (12-, 18-, and 24-in.-diam cylinders, 42-in. high) with no raschig rings. With rings randomly loaded in the vessels only the 24-in. cylinder could be made critical and then only when loaded with the 0.5 wt% borated rings. The minimum critical volume for this system, poisoned with 19.27 vol% borosilicate-glass rings containing 0.5 wt% boron, was determined to occur at about 300 g Pu/liter as compared to 175-to 200-g Pu/liter without the rings. The minimum critical mass occurred at ≈110-g Pu/liter with the system poisoned, as compared with 30-g Pu/liter if the system had not been poisoned. Exponential measurements on the subcritical assemblies, loaded with 4 wt% borated rings displacing 18.78 vol% solution, indicated that negative bucklings existed for all plutonium nitrate solutions having concentrations below 391-g Pu/liter. Similar measurements on the subcritical assemblies, loaded with 1 wt% borated stainless-steel rings displacing 27 vol% solution, indicated that negative bucklings existed for all concentrations below 412-g Pu/liter.Comparisons between the experimental data and the results of several calculational methods indicate that the validity of a particular calculational technique may be limited to a small concentration region. By treating the raschig rings as vertical parallel tubes displacing an equal volume of solution and using the Monte Carlo code KENO with GAMTEC-II cross sections averaged over the energy spectrum of the plutonium solution, keff values were calculated to within 2% of unity for the experimental critical assemblies presented in this paper. Other calculational methods and cross-section sets used resulted in values of keff departing from unity by as much as 12% low to 6% high, depending on the plutonium concentration. The various methods used are discussed in this paper.
