New Releases by David Hobbs

The current design of the Salt Waste Processing Facility (SWPF) includes an auxiliary facility, the Actinide Finishing Facility, which provides a second contact of monosodium titanate (MST) to remove soluble actinides and strontium from waste if needed. This treatment will occur after cesium removal by Caustic-Side Solvent Extraction (CSSX). Although the process changes and safety basis implications have not yet been analyzed, provisions also exist to recover the MST from this operation and return to the initial actinide removal step in the SWPF for an additional (third) contact with fresh waste. A U.S. Department of Energy (DOE) request identified the need to study the following issues involving this application of MST: Determine the effect of organics from the solvent extraction (CSSX) process on radionuclide sorption by MST; Determine the efficiency of re-using MST for multiple contacts; and Examine fissile loading on MST under conditions using a waste containing significantly elevated concentrations of plutonium, uranium, neptunium, and strontium. This report describes the results of three experimental studies conducted to address these needs: (1) Addition of high concentrations of entrained CSSX solvent had no noticeable effect, over a two week period, on the sorption of the actinides and strontium by MST in a direct comparison experiment. (2) Test results show that MST still retains appreciable capacity after being used once. For instance, reused MST--in the presence of entrained solvent--continued to sorb actinides and strontium. (3) A single batch of MST was used to sequentially contact five volumes of a simulant solution containing elevated concentrations of the radionuclides of interest. After the five contacts, we measured the following solution actinide loadings on the MST: plutonium: 0.884 {+-} 0.00539 wt % or (1.02 {+-} 0.0112) E+04 {micro}g/g MST, uranium: 12.1 {+-} 0.786 wt % or (1.40 {+-} 0.104) E+05 {micro}g/g MST, and neptunium: 0.426 {+-} 0.00406 wt % or (4.92 {+-} 0.0923) E+03 {micro}g/g MST. (4) Over the duration of an experiment with the sequential strikes, the ability of MST to sorb actinides improved with additional strikes. This trend is counter-intuitive, but is confirmed by replicate experiments for plutonium, uranium, and neptunium. Conversely, over the duration of the experiment, the ability of MST to sorb strontium decreased the more it was used. This trend is confirmed by replicate experiment.

Thermochemical processes are being developed to provide global-scale quantities of hydrogen. A variant on sulfur-based thermochemical cycles is the Hybrid Sulfur (HyS) Process which uses a sulfur dioxide depolarized electrolyzer (SDE) to produce the hydrogen. In FY05, testing at the Savannah River National Laboratory (SRNL) explored a low temperature fuel cell design concept for the SDE. The advantages of this design concept include high electrochemical efficiency and small volumetric footprint that is crucial for successful implementation on a commercial scale. A key component of the SDE is the ion conductive membrane through which protons produced at anode migrate to the cathode and react to produce hydrogen. An ideal membrane for the SDE should have both low ionic resistivity and low sulfur dioxide transport. These features allow the electrolyzer to perform at high currents with low potentials, along with preventing contamination of both the hydrogen output and poisoning of the catalysts involved. Another key component is the electrocatalyst material used for the anode and cathode. Good electrocatalysts should be chemically stable and low overpotential for the desired electrochemical reactions. This report summarizes results from activities to evaluate different membrane and electrocatalyst materials for the SDE. Several different types of commercially-available membranes were analyzed for ionic resistance and sulfur dioxide transport including perfluorinated sulfonic acid, sulfonated poly-etherketone-ketone, and poly-benzimidazole membranes. Of these membrane types, the poly-benzimidazole (PBI) membrane, Celtec-L, exhibited the best combination of characteristics for use in an SDE. Testing examined the activity and stability of platinum and palladium as electrocatalyst for the SDE in sulfuric acid solutions. Cyclic and linear sweep voltammetry revealed that platinum provided better catalytic activity with much lower potentials and higher currents than palladium. Testing also showed that the catalyst activity is strongly influenced by concentration of the sulfuric acid. Various cell configurations were examined with respect to the deposition of electrocatalyst and use of conductive carbon materials such as carbon cloth and carbon paper. Findings from these evaluations and the results of the membrane and electrocatalyst testing, we prepared three different membrane electrode assemblies (MEA) for electrolyzer testing. The first MEA consisted of a Nafion{reg_sign} membrane with platinum electrocatalyst deposited on carbon cloths, which were heat pressed onto the membrane, an assembly identical to those used in proton exchange membrane fuel cells. The second MEA also used a Nafion membrane with the electrocatalysts deposited directly onto the membrane. The third MEA proved similar to the second but utilized a PBI membrane in place of the Nafion{reg_sign} membrane. Tailor of the membrane and catalysts properties for the SDE system was concluded as a required step for the technology to move forward. It was also recommended the evaluation of the tested and new developed materials at conditions closer to the SDE operating conditions and for longer period of time.

This book adopts a new and accessible approach to helping readers understand how management accounting contributes to decisions in a variety of organisational contexts. It sets out clear explanations of practical management accounting techniques in the context of the application of these techniques to decisions. It recognizes practice through case studies and summarises published research. Uniquely, it examines the analytical and critical issues that often influence decision makers operating within private and public sector organisations. Key features include: - Case studies of varying complexity that will allow students to work at their own level - Summaries of important research articles - Key learning objectives and end of chapter questions.

A Mathematical Dictionary for Schools contains over 500 definitions of technical terms found within GCSE syllabuses. Key words and phrases are explained in clear, simple language with illustrations to aid understanding of more difficult terms. It has been written for key stages 1/GCSE students but is also suitable for key stage 3 and is the ideal companion for coursework and revision.

A reference which gives details of all those ships whose primary role has been to operate aircraft at sea, including ships from the British Royal Navy, the Royal Australian Navy, the Royal Canadian Navy/Canadian Armed Forces and the Indian Navy, as well as many vessels that served with the US Navy.

This book for teachers suggests projects which cater for a wide range of concepts and skills, and links with other curriculum subjects.

NATO has traditionally relied on its technological superiority to offset the Warsaw Pact''s numerical advantage. This equation, however, is becoming increasingly difficult to sustain. Despite NATO''s considerably greater outlays for defense, the numerical balance continues to favor the Warsaw Pact and the technological "gap" between East and West is narrowing. To rectify this situation NATO has two courses of actionóembrace a spectrum of new technologies which offer the prospect of dramatic improvements in capability, or extract better value for the money from its defense allocations. These two possibilities need not be mutually exclusive, although historically they have been. Clearly, NATO must reform its approach to weapons procurement if it is to exploit new technology as effectively as possible in periods of budgetary stringency. The need for reform is evident: The Warsaw Pact spends less than NATO on defense but outproduces NATO in virtually every weapons category. This volume examines these problems and shows that in order to exploit available technologies at an affordable cost, NATO clearly must organize its defense procurement more efficiently. Co-published with the Atlantic Council of the United States.

Fortæller om forhistorien og tankegangen bag stjernekrigsprojekterne, herunder om den nuværende og den forventede teknologiske udvikling.