Synroc for Immobilising Excess Weapons Plutonium

1994 ◽  
Vol 353 ◽  
Author(s):  
A. Jostsons ◽  
E. R. Vance ◽  
D. J. Mercer ◽  
V. M. Oversby

AbstractThe immobilisation of excess weapons plutonium into Synroc can meet all of the important criteria discussed by the U.S. National Academy of Sciences (NAS)(1) for disposal, if the disposal option is pursued rather than options that exploit the energy value of plutonium. This paper summarises the relevant background of Pu incorporation into Synroc, the durability of Pu-containing Synroc and outlines a process flowsheet based on the experience with the 10 kg/hr Synroc Demonstration Plant at ANSTO. The extensive solid solubility of Pu in Synroc, coupled with a very high degree of chemical durability under hydrothermal conditions, makes Synroc ideal as a waste matrix for Pu disposal in deep boreholes to minimise diversion and proliferation risks.

1999 ◽  
Vol 556 ◽  
Author(s):  
S. V. Stefanovsky ◽  
S. V. Yudintse ◽  
B. S. Nikonov ◽  
B. I. Omelianenko ◽  
A. G. Ptashkin

AbstractStudying the Synroc, doped with a simulated HLW, we have found, along with conventional Synroc phases (zirconolite, perovskite, hollandite), an extra phase with a stoichiornetry (Ca, Mn, U, TR)4(U, TR, Zr, Ti) 2(AI, Ti)7O22. XRD and TEM study has shown this phase is related to a very rare mineral murataite. In the present work a ceramic based on murataite is studied. The ceramic samples in the system: Ca-Mn-Ti-Zr-U-Ce-AI-Fe-O were produced and examined in details using XRD, SEM/EDS, TEM, and optical microscopy. Total amount of actinide (U) and rare earth (Ce, Gd) elements in the murataite exceeds 20 wt%. Isomorphic substitution schemes in the structures of synthetic and natural murataites are discussed. High isomorphic capacity of the murataite structure towards actinides and REEs, flexibility of its composition, feasibility of synthesis by melting, including a cold crucible melting, and very high chemical durability under hydrothermal conditions make the murataite-based ceramics very promising for actinides and excess weapon Pu fixation.


Author(s):  
Lynne K. Smith ◽  
Kathleen K. Clodfelter

Abstract In 1957, the National Academy of Sciences concluded that the most promising disposal option for radioactive wastes was burial in deep geologic repositories situated in salt formations. In 1981, after decades of study, the United States initiated construction of the Waste Isolation Pilot Plant (WIPP) at a desert site 41.6 km (26 miles) southeast of Carlsbad, New Mexico. This paper provides an overview of the history and the regulatory and public process to permit a repository for disposal of transuranic wastes. In addition, the process to ensure its long-term operation in a safe and environmentally sound manner will also be discussed.


Author(s):  
Cecil E. Hall

The visualization of organic macromolecules such as proteins, nucleic acids, viruses and virus components has reached its high degree of effectiveness owing to refinements and reliability of instruments and to the invention of methods for enhancing the structure of these materials within the electron image. The latter techniques have been most important because what can be seen depends upon the molecular and atomic character of the object as modified which is rarely evident in the pristine material. Structure may thus be displayed by the arts of positive and negative staining, shadow casting, replication and other techniques. Enhancement of contrast, which delineates bounds of isolated macromolecules has been effected progressively over the years as illustrated in Figs. 1, 2, 3 and 4 by these methods. We now look to the future wondering what other visions are waiting to be seen. The instrument designers will need to exact from the arts of fabrication the performance that theory has prescribed as well as methods for phase and interference contrast with explorations of the potentialities of very high and very low voltages. Chemistry must play an increasingly important part in future progress by providing specific stain molecules of high visibility, substrates of vanishing “noise” level and means for preservation of molecular structures that usually exist in a solvated condition.


1996 ◽  
pp. 4-15
Author(s):  
S. Golovaschenko ◽  
Petro Kosuha

The report is based on the first results of the study "The History of the Evangelical Christians-Baptists in Ukraine", carried out in 1994-1996 by the joint efforts of the Department of Religious Studies at the Institute of Philosophy of the National Academy of Sciences of Ukraine and the Odessa Theological Seminary of Evangelical Christian Baptists. A large-scale description and research of archival sources on the history of evangelical movements in our country gave the first experience of fruitful cooperation between secular and church researchers.


1996 ◽  
pp. 45-46
Author(s):  
Borys Lobovyk

"PHENOMENON OF RELIGION" - under this name on June 20-21, 1996, the All-Ukrainian Colloquium, convened by the Department of Religious Studies and the Ukrainian Association of Religious Studies took place at the Institute of Philosophy of the National Academy of Sciences of Ukraine. The purpose of the colloquium is to discuss the topical issues of Ukrainian religious studies concerning the nature, essence and functionality of religion as a social and historical phenomenon.


1998 ◽  
pp. 39-41
Author(s):  
Oleksandr N. Sagan

On April 22, 1998, on the occasion of the 65th anniversary of the publication of Arsen Rychinsky's "Problems of Ukrainian Religious Consciousness" in Kremenets (Ternopil region), the First Rychinsky reading was held. The organizers of the conference were: Ukrainian Association of Religious Studies, Ternopil Medical Academy named after them. I.Gorbachevsky, Department of Religious Studies at the Institute of Philosophy named after G.S. Skovoroda, National Academy of Sciences of Ukraine, Kremenets Medical College.


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