Dupical

Cyclamen aldehyde Muguet aldehyde Dupical Aldehyde C7 Aldehyde CIO Oncidal... 

Tardieu M, Truffot-Pernot C, Carriere JP, Dupic Y, Landrieu P. Tuberculous meningitis dne to BCG in two previously healthy children. Lancet 1988 1(8583) 440-1. 

This preference for the E-allylic alcohol product for selenium catalyzed allylic oxidation was also investigated with PHP as oxidant. Allylic oxidation of a mixture of cis/trans dupical (10) yielded with both TBHP and PHP more than 95% of the E allylic alcohol (Figure 2), further demonstrating that selenium catalyzed oxidations are independent of the oxidant used. 

Dupical and Scentenal have fresh, floral, aldehydic odours, the others have varying proportions of floral and fruity notes. 

The Direct Use of PWR spent fuel in CANDU (DUPIC) safeguards neutron counter (DSNC) is a well-type neutron coincidence counter with 18 He detectors configured with appropriate shielding, which measures all types of highly active materials from the dry reprocessing process for CANDU bundles (Menlove et al. 1997). It derives plutonium and uranium contents from the measured contents. Plutonium- and uranium-curium ratios... 

The DUPIC safeguards neutron monitor (DSNM) monitors the rear access ports of the process glove boxes through total neutron monitoring using He detectors (Kim 2007). 

Bumup with RU and PU from PWR spent fuel (TANDEM), MW d/kg HE Bumup with DUPIC fuel... 

Several DUPIC variants have been identified. One option is to simply cut the PWR fuel elements into CANDU lengths ( 50 cm), straighten them, and weld new end-caps to the ends (optionally, the elements could be double-clad). The smaller diameter of PWR elements would enable the use of a 48- or 61-element fuel bimdle, which would significantly reduce the linear element ratings compared with those of a 37-element bundle. The low linear element ratings would enhance fuel performance, and would help to accommodate the variation in fissile content between elements. 

In the nominal DUPIC fuel cycle, spent PWR fuel, having a nominal burnup of 35 MW d/kg HE, would be processed into CANDU fuel. An additional burnup of >15 MW d/kg HE would then be obtained through irradiation in CANDU. 

The DUPIC fuel cycle offers several benefits to a country that has PWRs and CANDU reactors including... 

At the heart of the reference DUPIC fuel cycle is the OREOX process. During this dry process, uranium from spent PWR fuel is sequentially oxidized and reduced to a fine powder, which forms the starting material for fabrication of DUPIC fuel pellets. The powder is conditioned to improve sinterability, pressed into pellets, sintered to a high density, ground to final size, and seal-welded within Zircaloy sheaths. Because the fuel remains highly radioactive, all the processing must be done in hot cells. 

Detailed reactor physics assessments have been performed for the DUPIC fuel, including lattice studies, detailed time-dependent fuel management simulations, and LOCA analysis (Choi et al. 1997). These studies confirm that DUPIC fuel can be accommodated within existing CANDU reactors. Some of the key results of these studies are summarized below. 

Because DUPIC fuel has a faster dynamic response than UO2 due to the lower delayed neutron fraction and lower prompt neutron lifetime for plutonium isotopes, the same positive reactivity insertion will result in a faster response than for UO2. To compensate for this in a postulated large LOCA, void reactivity for the DUPIC fuel was reduced by adding a small amount of neutron absorber to the center element (26 g of natural dysprosium). This is an embodiment of the LVRF concept and reduces void reactivity sufficiently so that the power pulse with the DUPIC fuel is lower than that with natural uranium. The downside, of course, is reduced bumup without the neutron poison the bmnup of the DUPIC fuel is 18.8 MW d/kg HE with the burnable poison, the bumup drops to 15 MW d/kg HE, which is still double that of NUE fuel (Table 15.8). 

Characteristics of Different DUPIC Core Performance with Various Spent PWR Fuel Types... 

Initial Enriched in PWR (%235U) Batch Size in PWR DUPIC Fuel Types Equilibrium Discharge Burnup (MWd/kgHE) Instantaneous Calculation Peak Powers (kW) CPPF... 

Choi, Fl.B., B.W. Rhee, and Fl.S. Park. 1997. Physics Study on Direct Use of Spent Pressurized Water Reactor Fuel in CANDU (DUPIC). Nuclear Sceince and Engineering 126, 80-93. 

Keil, H., P.G. Boczar, and H.S. Park. 1992. Options for the Direct Use of Spent PWR Fuel in CANDU (DUPIC), Proceedings of the 3rd International Conference on CANDU Fuel, October 4-8, Chalk River, Canada. 

LEE, J.S., et al.. Research and development program of KAERI for DUPIC (Direct Use of Spent PWR Fuel in CANDU Reactors), conceptual study on the DUPIC fuel manufacturing technology, GLOBAL 93, (Proc. Int. Conf on future energy systems Emerging nuclear fuel cycles and waste disposal options, Seattle, Washington, Sept. 1993), ANS/ENS. 

Figure 13.1 SFR pyroprocess development plan. PRIDE, pyroprocessing integrated inactive demonstration facility ACRE, advanced spent fuel conditioning process facility DFDF, dupic fuel development facility 3S, safety, security, safeguards.

From a proliferation and security perspective, it would be preferable to destroy or use this plutonium, rather than entomb it, presuming no access ( intrusion ) or use is allowed or possible for a historic timescale of a miUion or so years. Interestingly, LWR spent fuel is at about 0.9% fissile, which is why France can and does recycle today, and why this used recycled fuel could also be recycled again directiy again in CANDU (in the so-called DUPIC cycle). 

---