CLOSURE WELDING RADIOACTIVE MATERIALS CONTAINERS AT THE DEPARTMENT OF ENERGY (DOE) HANFORD SITE

The Department of Energy's (DOE) responsibility for the disposition of radioactive materials has given rise to several unique welding applications. Many of these materials require packaging into containers for either Interim or long-term storage. It is not uncommon that final container fabrication, i.e., closure welding, is performed with these materials already placed into the container. Closure welding is typically performed remote to the container, and routine post-weld testing and nondestructive examination (NDE) are often times not feasible. Fluor Hanford has packaged many such materials in recent years as park of the Site's cleanup mission. In lieu of post-weld testing and NDE, the Fluor-Hanford approach has been to establish weld quality through ''upfront'' development and qualification of welding parameters, and then ensure parameter compliance during welding. This approach requires a rigor not usually afforded to typical welding development activities, and may involve statistical analysis and extensive testing, including burst, drop, sensitive leak testing, etc. This paper provides an instructive review of the development and qualification activities associated with the closure of radioactive materials containers, including a brief report on activities for closure welding research reactor, spent nuclear fuel (SNF) overpacks at the Hanford Site

OREGON STATE UNIVERSITY (OSU) TRAINING RESEARCH ISOTOPE GENERAL ATOMICS (TRIGA) OVERPACK CLOSURE WELDING PROCESS PARAMETER DEVELOPMENT & QUALIFICATION

Spent Nuclear Fuel (SNF) from the Oregon State University (OSU) TRIGA{reg_sign} Reactor is currently being stored in thirteen 55-gallon drums at the Hanford Site's low-level burial grounds. This fuel is soon to be retrieved from buried storage and packaged into new containers (overpacks) for interim storage at the Hanford Interim Storage Area (ISA). One of the key activities associated with this effort is final closure of the overpack by welding. The OSU fuel is placed into an overpack, a head inserted into the overpack top, and welded closed. Weld quality, for typical welded fabrication, is established through post-weld testing and nondestructive examination (NDE); however, in this case, once the SNF is placed into the overpack, routine testing and NDE are not feasible. An alternate approach is to develop and qualify the welding process/parameters, demonstrate beforehand that they produce the desired weld quality, and then verify parameter compliance during production welding. Fluor engineers have developed a Gas Tungsten Arc Welding (GTAW) technique and parameters, demonstrating that weld quality requirements for closure of packaged SNF overpacks are met, using this alternate approach. The following reviews the activities performed for this development and qualification effort

A computer program for processing data from amino acid analysis and for the calculation of molecular weights from those data

A computer program is described for the calculation of the complete amino acid composition of a protein from the analytical data. The program also derives a molecular weight on the basis of the amino acid composition. The use of the program for the determination of the molecular weights of the liver carboxylesterases of chicken, horse, ox, and sheep is described

Disposition of phenytoin and phenobarbitone in the isolated perfused human placenta

b 1. The disposition of the anti‐epileptic agents phenytoin (PHT) and pheno‐barbitone (PB) was investigated in lobules of term human placentae perfused using separate maternal and fetal circulations for 6 h periods. 2. No evidence for metabolism of PHT or PB to their p‐hydroxylated or other derivatives was found either in perfused lobules or by incubation with placental microsomes. 3. Both PHT and PB were readily transferred across the placenta after administration to either the maternal or fetal perfusates. 4. PHT, unlike PB, showed considerable accumulation in placental tissue. Copyrigh

Efeitos da compactação em algumas propriedades físicas do solo e seu reflexo no desenvolvimento das raízes de plantas de soja Effects of soil compaction on some physical properties and on root growth of soybean

Estudou-se o efeito de vários níveis de compactação na densidade do solo, porosidade total e resistência à penetração, objetivando determinar o nível que impede o desenvolvimento das raízes de plantas de soja. O trabalho foi realizado em casa de vegetação, com amostras deformadas do horizonte superficial de uma terra roxa estruturada e de um latossolo roxo, controlando os níveis de compactação e o teor de água. A influência da compactação no desenvolvimento das raízes foi avaliada um mês após a germinação. Os valores de densidade do solo, para um mesmo nível de compactação, foram maiores para a terra roxa estruturada. O teor de água ótimo para a compactação foi de 21,0% para a terra roxa estruturada e de 29,8 para o latossolo roxo. A compactação artificial do solo acarretou aumento da resistência à penetração e diminuição da porosidade total. A elevação da sua densidade de 0,90 para 1,30 kg/m³ para a terra roxa estruturada, e de 0,90 para 1,23 kg/m³ para o latossolo roxo, promoveu, respectivamente, diminuição de 39 e de 41% na massa seca das raízes. O desenvolvimento das raízes das plantas ficou impedido quando a densidade do solo atingiu valores de 1,30 e 1,23 kg/m³, respectivamente, para a terra roxa estruturada e o latossolo roxo.<br>The effects of an artificial soil compaction on soil density, total porosity and soil resistance to penetration were studied with the aim to determine the level that obstructs root development of soybean. The work was carried out in greenhouse, with disturbed samples of surface horizon of an Ultisol ("Terra Roxa Estruturada") and an Oxisol ("Latossolo Roxo"), and controlling the level of compaction and the soil water content. The influence of soil compaction on root growth of soybean was evaluated one month after germination. The Ultisol showed higher soil density values than the Oxisol for the same compaction level. The optimum soil water content value for compaction was 21.0% in the Ultisol and 29.8% in the Oxisol. The increase on compaction level resulted (on the both soils) in an increase of mechanical impedance of penetration and decrease of total porosity. The increase in soil density of 0.90 to 1.30 kg/m³ in the Ultisol, and 0.90 to 1.23 kg/m³ in the Oxisol reduced the development of soybean roots, respectively, in 39 and 41%. The development of the soybean roots was severely reduced for soil density values of 1.30 and 1.23 kg/m³, respectively, in the Ultisol and in the Oxisol