Recent scientific research and changes in regulatory policies have led to reductions in the allowable discharges of several contaminant metals, including copper, into surface water. Low target concentrations and variable outfall conditions challenge the efficacy of traditional treatment technologies such as ion exchange. In reviewing various treatment options, scientists and engineers at the Savannah River Site (SRS) developed a treatment strategy focusing on toxicity reduction (rather than the removal of the copper) and demonstrated that the method is viable and promising for mitigating copper toxicity. The resulting outfall chemistry protects the ecosystem in the receiving stream in a manner that is equal to, or better than, technologies that remove copper to the emerging regulatory levels. Further, the proposed toxicity reduction strategy results in collateral beneficial changes in outfall water chemistry such that the outfall more closely matches the chemistry of natural streams for key parameters such as the dissolved organic carbon (DOC). The detoxification process is based on the EPA BLM. Specifically, modeling indicates that copper toxicity can be mitigated by modest additions of natural organic carbon and that the amount of amendment needed can be determined based on pH and stream flow. The organic carbon amendments proposed for the …

The data analysis objectives are: (1) Independent assessment of technology, focused on fuel cell system and hydrogen infrastructure:performance, operation, and safety; (2) Leverage data processing and analysis capabilities from the fuel cell vehicle Learning Demonstration project and DoD Forklift Demo; (3) Establish a baseline of real-world fuel cell operation and maintenance data and identify technical/market barriers; (4) Support market growth of fuel cell technologies by reporting on technology features relevant to the business case; and (5) Report on technology to fuel cell and hydrogen communities and stakeholders.

In this paper we show that spinel ferrite nanocrystals (NiFe{sub 2}O{sub 4}, and CoFe{sub 2}O{sub 4}) can be texturally embedded inside a ZnO matrix by ion implantation and post-annealing. The two kinds of ferrites show different magnetic properties, e.g. coercivity and magnetization. Anomalous Hall effect and positive magnetoresistance have been observed. Our study suggests a ferrimagnet/semiconductor hybrid system for potential applications in magneto-electronics. This hybrid system can be tuned by selecting different transition metal ions (from Mn to Zn) to obtain various magnetic and electronic properties.

Human mesenchymal stem cells (hMSC) are critical for tissue regeneration. How hMSC respond to genotoxic stresses and potentially contribute to aging and cancer remain underexplored. We demonstrated that ionizing radiation induced cellular senescence of hMSC over a period of 10 days, showing a critical transition between day 3 and day 6. This was confirmed by senescence-associated beta-galactosidase (SA-{beta}-gal) staining, protein expression profiles of key cell cycle regulators (retinoblastoma (Rb) protein, p53, p21{sup waf1/Cip1}, and p16{sup INK4A}), and senescence-associated secretory phenotypes (SASPs) (IL-8, IL-12, GRO, and MDC). We observed dramatic cytoskeletal reorganization of hMSC through reduction of myosin-10, redistribution of myosin-9, and secretion of profilin-1. Using a SILAC-based phosphoproteomics method, we detected significant reduction of myosin-9 phosphorylation at Ser1943, coinciding with its redistribution. Importantly, through treatment with cell permeable inhibitors (4,5,6,7-tetrabromo-1H-benzotriazole (TBB) and 2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole (DMAT)), and gene knockdown using RNA interference, we identified CK2, a kinase responsible for myosin-9 phosphorylation at Ser1943, as a key factor contributing to the radiation-induced senescence of hMSC. We showed that individual knockdown of CK2 catalytic subunits CK2{alpha} and CK2{alpha}{prime} induced hMSC senescence. However, only knockdown of CK2{alpha} resulted in morphological phenotypes resembling those of radiation-induced senescence. These results suggest that CK2{alpha} and CK2{alpha}{prime} play differential …

In 2007, we used radio and acoustic telemetry to evaluate the migratory behavior, survival, mortality, and delay of subyearling fall Chinook salmon in the Clearwater River and Lower Granite Reservoir. Monthly releases of radio-tagged fish ({approx}95/month) were made from May through October and releases of 122-149/month acoustic-tagged fish per month were made from August through October. We compared the size at release of our tagged fish to that which could have been obtained at the same time from in-river, beach seine collections made by the Nez Perce Tribe. Had we relied on in-river collections to obtain our fish, we would have obtained very few in June from the free-flowing river but by late July and August over 90% of collected fish in the transition zone were large enough for tagging. Detection probabilities of radio-tagged subyearlings were generally high ranging from 0.60 (SE=0.22) to 1.0 (SE=0) in the different study reaches and months. Lower detection probabilities were observed in the confluence and upper reservoir reaches where fewer fish were detected. Detection probabilities of acoustic-tagged subyearlings were also high and ranged from 0.86 (SE=0.09) to 1.0 (SE=0) in the confluence and upper reservoir reaches during August through October. Estimates of the joint …

The U.S. Department of Energy (DOE) Office of River Protection’s Waste Treatment Plant (WTP) is being designed and built to pre-treat and then vitrify a large portion of the wastes in Hanford’s 177 underground waste storage tanks. The WTP consists of three primary facilities—pretreatment, low-activity waste (LAW) vitrification, and high-level waste (HLW) vitrification. The pretreatment facility will receive waste piped from the Hanford tank farms and separate it into a high-volume, low-activity liquid stream stripped of most solids and radionuclides and a much smaller volume of HLW slurry containing most of the solids and most of the radioactivity. Many of the vessels in the pretreatment facility will contain pulse jet mixers (PJM) that will provide some or all of the mixing in the vessels. Pulse jet mixer technology was selected for use in black cell regions of the WTP, where maintenance cannot be performed once hot testing and operations commence. The PJMs have no moving mechanical parts that require maintenance. The vessels with the most concentrated slurries will also be mixed with air spargers and/or steady jets in addition to the mixing provided by the PJMs. Pulse jet mixers are susceptible to overblows that can generate large hydrodynamic forces, forces …