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Major Contaminant (major + contaminant)
Selected AbstractsAn upper limit to polarized submillimetre emission in Arp 220MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2007Michael Seiffert ABSTRACT We report the results of pointed observations of the prototypical ultraluminous infrared galaxy (ULIRG) Arp 220 at 850 ,m using the polarimeter on the Submillimetre Common User Bolometer Array instrument on the James Clerk Maxwell Telescope. We find a Bayesian 99 per cent confidence upper limit on the polarized emission for Arp 220 of 1.54 per cent, averaged over the 15-arcsec beam-size. Arp 220 can serve as a proxy for other, more distant such galaxies. This upper limit constrains the magnetic field geometry in Arp 220 and also provides evidence that polarized ULIRGs will not be a major contaminant for next-generation cosmic microwave background polarization measurements. [source] Treatment of Highly Contaminated Groundwater: A SITE Demonstration ProjectREMEDIATION, Issue 3 2001Daniel Sullivan From September through November 1994, the U.S. Environmental Protection Agency (EPA) conducted a field demonstration of the remediation of highly contaminated groundwater at the Nascolite Superfund site located in Millville, New Jersey. Besides high concentrations of the major contaminant, methyl methacrylate (MMA), the groundwater also contained small amounts of volatile and semivolatile organic compounds. ZenoGem® technology, an integrated bioreactor and ultrafiltration membrane system, was employed for this demonstration project. Approximately 30,000 gallons of groundwater containing MMA in concentrations of 567 to 9,500 milligrams per liter (mg/L) and chemical oxygen demand (COD) values ranging from 1,490 to 19,600 mg/L was treated. The demonstration focused on the system's ability to remove MMA and reduce COD from the groundwater. Results of the three-month demonstration showed that average MMA and COD removal efficiencies were greater than 99.9 and 86.9, respectively. The total cost of treatment, depending on the duration of the project, is estimated to vary from $0.22 to $0.55 (in 1994 dollars) per gallon of groundwater treated. © 2001 John Wiley & Sons. [source] Enantioselective analysis of primaquine and its impurity quinocide by capillary electrophoresisBIOMEDICAL CHROMATOGRAPHY, Issue 3 2009Abdalla A. Elbashir Abstract A capillary electrophoretic (CE) method for the baseline separation of the enantiomers of primaquine diphosphate (PQ) and quinocide (QC) (a major contaminant) in pharmaceutical formulations is proposed. Both components were separated under the following conditions: 50 mm tris phosphate buffer (pH 3.0) containing 15 mm hydroxypropyl- , -cyclodextrin (HP- , -CD) as background electrolyte; applied voltage, 16 kV; capillary temperature, 25°C; detection wavelength, 254 nm; hydrostatic injection, 10 s. The separations were conducted using a 35 cm length and 50 µm i.d. uncoated fused silica capillary column. Under the optimized conditions, the components were successfully separated in about 5 min. Intraday precision of migration time and corrected peak areas when expressed as relative standard deviation ranged from 0.17 to 0.45 and 2.60 to 3.94%, respectively, while the interday precision ranged from 2.59 to 4.20 and 3.15 to 4.21%, respectively. After the validation exercise, the proposed method was applied for the determination of QC impurity in PQ formulations. Copyright © 2008 John Wiley & Sons, Ltd. [source] Proteome analysis of the culture environment supporting undifferentiated mouse embryonic stem and germ cell growthELECTROPHORESIS, Issue 10 2007Nicolas Buhr Abstract The therapeutical interest of pluripotent cells and ethical issues related to the establishment of human embryonic stem cell (ESC) or embryonic germ cell (EGC) lines raise the understanding of the mechanism underlying pluripotency to a fundamental issue. Establishing a protein pluripotency signature for these cells can be complicated by the presence of unrelated proteins produced by the culture environment. Here, we have analyzed the environment supporting ESC and EGC growth, and established 2-D reference maps for each constituent present in this culture environment: mouse embryonic fibroblast feeder cells, culture medium (CM) and gelatin. The establishment of these reference maps is essential prior to the study of ESC and EGC specific proteomes. Indeed, these maps can be subtracted from ESC or EGC maps to allow focusing on spots specific for ESCs or EGCs. Our study led to the identification of 110 unique proteins from fibroblast feeder cells and 23 unique proteins from the CM, which represent major contaminants of ESC and EGC proteomes. For gelatin, no collagen-specific proteins were identified, most likely due to difficulties in resolution and low quantities. Furthermore, no differences were observed between naive and conditioned CM. Finally, we compared these reference maps to ESC 2-D gels and isolated 17 ESC specific spots. Among these spots, proteins that had already been identified in previous human and mouse ESC proteomes were identified but no apparent ESC-specific pluripotency marker could be identified. This work represents an essential step in furthering the knowledge of environmental factors supporting ESC and EGC growth. [source] Co-composting of pharmaceutical wastes in soilLETTERS IN APPLIED MICROBIOLOGY, Issue 4 2001T.F. Guerin Aims:,Soils at a commercial facility had become contaminated with the pharmaceutical chemical residues, Probenecid and Methaqualone, and required remediation. Methods and Results:,Soil composting was investigated as an alternative to incineration for treatment. In laboratory trials, a factorial experimental design was used to evaluate organic matter amendment type and concentration, and incubation temperature. In pilot scale trials, Probenecid was reduced from 5100 mg kg,1 to < 10 mg kg,1 within 20 weeks in mesophilic treatments. An 8 tonne pilot scale treatment confirmed that thermophilic composting was effective under field conditions. In the full-scale treatment, 180 tonnes of soil were composted. Initial concentrations of the major contaminants in the full-scale compost treatment were 1160 mg kg,1 and 210 mg kg,1, for Probenecid and Methaqualone, respectively. Probenecid concentration reached the target level of 100 mg kg,1 in 6 weeks, and removal of Methaqualone to < 100 mg kg,1 was achieved after 14 weeks. Conclusions:,Co-composting was effective in reducing soil concentrations of Probenecid and Methaqualone residues to acceptable values. Significance and Impact of the Study:,Co-composting is a technology that has application in the remediation of pharmaceutical contaminants in soil. [source] | ||||||||||