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[en] In 1959 the Los Alamos Scientific Laboratory (LASL) proposed design requirements for an alpha-gamma box system. Among the requirements was a provision for conveniently removing a contaminated cell liner (alpha-gamma box) from an operating cell. Various situations, such as a change in program direction, outmoded equipment, or an unexpected development, could result in a decision to replace a cell liner and reuse the cell for another purpose. The contaminated cell liners could either be stored temporarily for possible future use or disposed of at the LASL contaminated Waste Disposal Area. LASL's experience removing used hot cell liners from operating cells is described
[en] The LASL Fast Liner Experiment explored a fusion concept in which a suitably prepared plasma is adiabatically compressed to thermonuclear temperatures and densities by a rapidly imploding solid metal liner. A prepared plasma having β>1 is in contact with the liner and end plugs, and contains an embedded magnetic field to inhibit thermal conduction. Cylindrical liners are magnetically imploded by a large axial current carried in the liner shell. The experimental work to develop this concept involved attempts to provide a suitable plasma for liner implosions and studies of magnetically driven liner implosions. In the plasma preparation experiments, a coaxial plasma gun was used to inject plasma into a simulated liner geometry. About 2μs after plasma injection a density of 3x1016cm-3, a temperature of 40eV, and an embedded azimuthal field of 10kG were measured. In the implosion studies, cylindrical aluminium liners were imploded by Z-pinch currents of 10-15MA. Symmetrical implosions having velocities in the range 4-6x105cm.s-1 have been obtained for liners with typical initial dimensions of 10cm length, 5cm diameter and 1mm thickness using a 1.8-MJ capacitor bank. Implosion velocities of 9-10x105cm.s-1 were observed for 6-cm-long, 5.6-cm-diameter, 1-mm-thick liners driven by a 2.4-MJ bank. In each case, current drive to the liner was maintained until the liner converged on the axis. The observed velocities and trajectories agree well with the predictions of a one-dimensional code, CHAMISA. (author)
[en] Investigations have been made into the deformation behaviour of steel lining of the boreholes in the HAW test field, which is an underground experimental facility used for the investigation of he effects of storage of nuclear waste in salt formations. The HAW test field consists of two parallel galleries in an anticline type of salt formation. From each gallery four vertical boreholes have been drilled at equal distance. In two of these boreholes electrical heaters have been placed and in the remaining boreholes heat producing nuclear sources will be installed. A lining of steel has been placed into the boreholes to guarantee the continuous retrievability of the radio-active canisters over the complete test period. During the experiments with the electrically heated holes, ovality of the cross section of the lining was measured. The results of the investigation into a possible cause of this type of deformation are presented in this report. It was concluded that bending cannot be the cause of the ovality found in the lining. It is expected that the ovality is caused by pressure load variations in circumferential direction. (author). 6 refs.; 10 figs.; 4 tabs
[en] At the request of Area Completion Engineering and in support of the 488-1D Ash Basin closure, the Savannah River National Laboratory (SRNL) performed hydrologic simulations of the revised 488-1D Ash Basin closure cap design using the Hydrologic Evaluation of Landfill Performance (HELP) model. The revised design substitutes a MicroDrain Liner®-60-mil low-density polyethylene geomembrane structurally integrated with 130-mil drainage layer-for the previously planned drainage/barrier system-300-mil geosynthetic drainage layer (GDL), 300-mil geosynthetic clay liner (GCL), and 6-inch common fill soil layer. For a 25-year, 24-hour storm event, HELP model v3.07 was employed to (1) predict the peak maximum daily hydraulic head for the geomembrane layer, and (2) ensure that South Carolina Department of Health and Environmental Control (SCDHEC) requirements for the barrier layer (i.e., ≤ 12 inches hydraulic head on top of a barrier having a saturated hydraulic conductivity ≤1.0E-05 cm/s) will not be exceeded. A 25-year, 24-hour storm event at the Savannah River Site (SRS) is 6.1 inches rainfall (Weber 1998). HELP model v3.07 results based upon the new planned cap design suggest that the peak maximum daily hydraulic head on the geomembrane barrier layer will be 0.15 inches for a minimum slope equal to 3%, which is two orders of magnitude below the SCDHEC upper limit of 12 inches.
[en] Urothelial carcinomas originate from the epithelial cells of the inner lining of the bladder and may appear as single or as multiple synchronous tumors. Patients with urothelial carcinomas frequently show recurrences after treatment making follow-up necessary. The leading hypothesis explaining the origin of meta- and synchronous tumors assumes a monoclonal origin. However, the genetic relationship among consecutive tumors has been shown to be complex in as much as the genetic evolution does not adhere to the chronological appearance of the metachronous tumors. Consequently, genetically less evolved tumors may appear chronologically later than genetically related but more evolved tumors. Forty-nine meta- or synchronous urothelial tumors from 22 patients were analyzed using expression profiling, conventional CGH, LOH, and mutation analyses. We show by CGH that partial chromosomal losses in the initial tumors may not be present in the recurring tumors, by LOH that different haplotypes may be lost and that detected regions of LOH may be smaller in recurring tumors, and that mutations present in the initial tumor may not be present in the recurring ones. In contrast we show that despite apparent genomic differences, the recurrent and multiple bladder tumors from the same patients display remarkably similar expression profiles. Our findings show that even though the vast majority of the analyzed meta- and synchronous tumors from the same patients are not likely to have originated directly from the preceding tumor they still show remarkably similar expressions profiles. The presented data suggests that an expression profile is established early in tumor development and that this profile is stable and maintained in recurring tumors
[en] To ensure that the sealing shell is able to sustain all deformations of the depressurization container though directly supported on the depressurization container by spacers, these spacers are constructed as elastic members e.g. from rubber which are bound to the sealing shell but are supported on the container wall by a sliding plane. (P.K.)
[en] Spherically imploding plasma liners, formed by merging hypersonic plasma jets, are a proposed standoff driver to compress magnetized target plasmas to fusion conditions. Here, in this paper, the parameter space and physics criteria are identified for a subscale, plasma-liner-formation experiment to provide data, e.g., on liner ram-pressure scaling and uniformity, that are relevant for addressing scientific issues of full-scale plasma liners required to achieve fusion conditions. Lastly, based on these criteria, we quantitatively estimate the minimum liner kinetic energy and mass needed, which informed the design of a subscale plasma liner experiment now under development.