Accurate and precise means for quantifying Ta in tissues, bodily fluids, and bone is critical in understanding anticipated safety-profiles for tantalum oxide (TaO) nanoparticle-based X-ray/CT diagnostic imaging agents and has prompted the development of three digestion methods which are the focus of this work. Spike recovery studies were employed to evaluate bias, precision, and sample matrix effects in the quantification of Ta in (1) liver, blood and femur by microwave-assisted digestion, (2) urine by open-beaker digestion, and (3) carcass, liver and feces by dry-ash digestion. All analyses were performed with inductively coupled plasma optical emission spectrometry (ICP-OES). Spike recoveries were 98.5-102.3% for all biological matrices except femur (91.6%); however, a modified version of the original microwave digestion procedure improved the recovery of Ta in femur to 103.8%. Precision of spike recovery reported as one standard deviation ranged from 0.1 to 3.8% for within-run and from 0.5 to 3.3% for overall recovery depending on the tissue type and digestion method. Limit of detection (LOD) was 0.006 to 6 mg Ta per g and limit of quantification (LOQ) was 0.02 to 20 mg Ta per g depending on the method. The presented methods were applied to the determination of Ta in liver, kidney, spleen and carcass from an in vivo TaO nanoparticle retention study, and the results for percent injected dose (% ID) of Ta retained are given. † Electronic supplementary information (ESI) available: Sample digestion reagents, instrument calibration standards, tantalum oxide nanoparticle contrast agent digestion procedures and results, within-run recovery and precision for each biological material per digestion method, and in vivo retention case study results. See

The U.S. Department of Energy's National Energy Technology Laboratory (DOE NETL) is exploring affordable technologies and processes to convert domestic coal and biomass resources to high-quality liquid hydrocarbon fuels. This interest is primarily motivated by the need to increase energy security and reduce greenhouse gas emissions in the United States. Gasification technologies represent clean, flexible and efficient conversion pathways to utilize coal and biomass resources. Substantial experience and knowledge had been developed worldwide on gasification of either coal or biomass. However, reliable data on effects of blending various biomass fuels with coal during gasification process and resulting syngas composition are lacking.In this project, GE Global Research performed a complete characterization of the gas, liquid and solid products that result from the co-gasification of coal/biomass mixtures. This work was performed using a bench-scale gasifier (BSG) and a pilot-scale entrained flow gasifier (EFG). This project focused on comprehensive characterization of the products from gasifying coal/biomass mixtures in a high-temperature, high-pressure entrained flow gasifier. Results from this project provide guidance on appropriate gas clean-up systems and optimization of operating parameters needed to develop and commercialize gasification technologies.GE's bench-scale test facility provided the bulk of high-fidelity quantitative data under temperature, heating rate, and residence time conditions closely matching those of commercial oxygen-blown entrained flow gasifiers. Energy and Environmental Research Center (EERC) pilot-scale test facility provided focused high temperature and pressure tests at entrained flow gasifier conditions. Accurate matching of syngas time-temperature history during cooling ensured that complex species interactions including homogeneous and heterogeneous processes such as particle nucleation, coagulation, surface condensation, and gas-phase reactions were properly reproduced and lead to representative syngas composition at the syngas cooler outlet. The experimental work leveraged other ongoing GE R&D efforts such as biomass gasification and dry feeding systems projects. Experimental data obtained under this project were used to provide guidance on the appropriate clean-up system(s) and operating parameters to coal and biomass combinations beyond those evaluated under this project.

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