51 research outputs found

    In-Flight Water Quality Monitoring on the International Space Station (ISS): Measuring Biocide Concentrations with Colorimetric Solid Phase Extraction (CSPE)

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    The colorimetric water quality monitoring kit (CWQMK) was delivered to the International Space Station (ISS) on STS-128/17A and was initially deployed in September 2009. The kit was flown as a station development test objective (SDTO) experiment to evaluate the acceptability of colorimetric solid phase extraction (CSPE) technology for routine water quality monitoring on the ISS. During the SDTO experiment, water samples from the U.S. water processor assembly (WPA), the U.S. potable water dispenser (PWD), and the Russian system for dispensing ground-supplied water (SVO-ZV) were collected and analyzed with the CWQMK. Samples from the U.S. segment of the ISS were analyzed for molecular iodine, which is the biocide added to water in the WPA. Samples from the SVOZV system were analyzed for ionic silver, the biocide used on the Russian segment of the ISS. In all, thirteen in-flight analysis sessions were completed as part of the SDTO experiment. This paper provides an overview of the experiment and reports the results obtained with the CWQMK. The forward plan for certifying the CWQMK as operational hardware and expanding the capabilities of the kit are also discussed

    Continuum Extrapolation of Moments of Nucleon Quark Distributions in Full QCD

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    Moments of light cone quark density, helicity, and transversity distributions are calculated in unquenched lattice QCD at β=5.5\beta = 5.5 and β=5.3\beta = 5.3 using Wilson fermions on 163×32 16^3 \times 32 lattices. These results are combined with earlier calculations at β=5.6\beta = 5.6 using SESAM configurations to study the continuum limit

    Continuum extrapolation of moments of nucleon quark distributions in full QCD

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    Moments of light cone quark density, helicity, and transversity distributions are calculated in unquenched lattice QCD at β=5.5\beta = 5.5 and β=5.3\beta = 5.3 using Wilson fermions on 163×32 16^3 \times 32 lattices. These results are combined with earlier calculations at β=5.6\beta = 5.6 using SESAM configurations to study the continuum limit.Comment: Lattice 2002 (hadronic matrix elements) 3 pages, 1 figur

    Design, Certification, and Deployment of the Colorimetric Water Quality Monitoring Kit (CWQMK)

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    In August 2009, an experimental water quality monitoring kit based on Colorimetric Solid Phase Extraction (CSPE) technology was delivered to the International Space Station (ISS) aboard STS-128/17A. The kit, called the Colorimetric Water Quality Monitoring Kit (CWQMK), was developed by a team of scientists and engineers from NASA s Habitability and Environmental Factors Division in the Space Life Sciences Directorate at Johnson Space Center, the Wyle Integrated Science and Engineering Group in Houston, Texas, the University of Utah, and Iowa State University. The CWQMK was flown and deployed as a Station Development Test Objective (SDTO) experiment on ISS. The goal of the SDTO experiment was to evaluate the acceptability of CSPE technology for routine water quality monitoring on ISS. This paper provides an overview of the SDTO experiment, as well as a detailed description of the CWQMK hardware and a summary of the testing and analysis conducted to certify the CWQMK for use on ISS. The results obtained from the SDTO experiment are also reported and discussed in detail

    Colorimetric-Solid Phase Extraction Technology for Water Quality Monitoring: Evaluation of C-SPE and Debubbling Methods in Microgravity

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    Colorimetric-solid phase extraction (C-SPE) is being developed as a method for in-flight monitoring of spacecraft water quality. C-SPE is based on measuring the change in the diffuse reflectance spectrum of indicator disks following exposure to a water sample. Previous microgravity testing has shown that air bubbles suspended in water samples can cause uncertainty in the volume of liquid passed through the disks, leading to errors in the determination of water quality parameter concentrations. We report here the results of a recent series of C-9 microgravity experiments designed to evaluate manual manipulation as a means to collect bubble-free water samples of specified volumes from water sample bags containing up to 47% air. The effectiveness of manual manipulation was verified by comparing the results from C-SPE analyses of silver(I) and iodine performed in-flight using samples collected and debubbled in microgravity to those performed on-ground using bubble-free samples. The ground and flight results showed excellent agreement, demonstrating that manual manipulation is an effective means for collecting bubble-free water samples in microgravity
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