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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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What’s in your Dubai chocolate? Nuclear scientists test pistachios for toxins
For the uninitiated, Dubai chocolate is a candy bar filled with pistachio and tahini cream and crispy pastry recently popularized by social media influencers. While it’s easy to dismiss as a viral craze now past its peak, the nutty green confection has spiked global pistachio demand, and growers and processors are ramping up production. That means more pistachios need to be tested for aflatoxins—a byproduct of a common crop mold.
S. N. Purohit
Nuclear Science and Engineering | Volume 9 | Number 3 | March 1961 | Pages 305-313
Technical Paper | doi.org/10.13182/NSE61-A25881
Articles are hosted by Taylor and Francis Online.
The time-dependent energy spectra, for times greater than the slowing-down time, were generated in a monatomic heavy gas with the help of a multigroup formalism. These spectra were obtained for the infinite as well as finite media of beryllium and graphite. The behavior of asymptotic energy spectra during the last stage of neutron thermalization and diffusion periods was studied. The thermalization time constant for the establishment of the final Maxwellian velocity distribution of neutrons, in a monatomic heavy gas, was estimated to be equal to (1.176ξΣs0υ0)−1. Total thermalization times for neutrons in beryllium and graphite were found to be equal to 114 and 238 µsec, respectively. Using the energy-dependent transport mean free path, the diffusion cooling coefficient for beryllium was calculated to be equal to 0.890 cm2 For graphite, under the constant diffusion coefficient assumption, the diffusion cooling coefficient was determined to be equal to 1.922 cm2.
