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The presence of hexahydro‐1,3,5‐trinitro‐1,3,5‐triazine (RDX) in soil and groundwater is a major contamination issue at many military facilities around the world. Gordonia sp. KTR9 metabolizes RDX as a nitrogen source for growth producing 4‐nitro‐2,4‐diazabutanal (NDAB) as a dead‐end product. Methylobacterium sp. strain JS178 degrades NDAB as a sole source of nitrogen for growth. A mixed culture of strains KTR9 and JS178 was able to completely degrade RDX. There was no difference in rate of RDX degradation by KTR9 alone or in co‐culture with JS178. The first‐order degradation coefficients of RDX and NDAB in the co‐culture were 0.08 hr?1 and 0.002 hr?1, respectively. In the co‐culture that initially contained RDX plus NDAB, strain JS178 degraded the NDAB that was produced by KTR9 as shown by a decrease in the molar yield of NDAB (from RDX) from 1.0 to –0.11. Co‐cultures of strains KTR9 and JS178 could be used to promote complete degradation of RDX in soils or groundwater. ©2016 Wiley Periodicals, Inc.  相似文献   
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Ionic liquids are studied intensively for different applications. They tend to be denoted as “green solvents”, largely because of their low vapour pressure. In recent years toxicity and biotoxicity of ionic liquids have also been investigated, which proved that not all of these are “green”. In this paper the use of ionic liquids based on choline chloride and ethylene glycol in electrochemistry is discussed in the context of their use as green solvents. Due to their low toxicity and ready biodegradability, these deep eutectic solvents are promising for the electrodeposition of metals. The influence of the use of these liquids as metal deposition baths on the waste water is investigated. Drag-out was found to be the most influencing parameter on the environmental impact of the process, as it is three times higher compared to classical solutions due to the higher viscosity of the ionic liquid. There are no major changes needed in the rinsing configuration of classic electroplating plants, and ion exchange to remove the metal out of the waste water was not hindered by the presence of the ionic liquid. The formation of by-products during the deposition of metals has to be further investigated and evaluated in consideration of the environmental impact.  相似文献   
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A fuzzy decision analysis method for integrating ecological indicators was developed. This was a combination of a fuzzy ranking method and the analytic hierarchy process (AHP). The method was capable of ranking ecosystems in terms of environmental conditions and suggesting cumulative impacts across a large region. Using data on land cover, population, roads, streams, air pollution, and topography of the Mid-Atlantic region, we were able to point out areas that were in relatively poor condition and/or vulnerable to future deterioration. The method offered an easy and comprehensive way to combine the strengths of fuzzy set theory and the AHP for ecological assessment. Furthermore, the suggested method can serve as a building block for the evaluation of environmental policies.  相似文献   
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Aerosol optical and microphysical parameters from severe haze events observed in October 2005 at Gwangju, Korea (35.10°N, 126.53°E) were determined from the ground using a multi-wavelength Raman lidar, a sunphotometer, and a real-time carbon particle analyzer and from space using satellite retrievals. Two different aerosol types were identified based on the variability of optical characteristics for different air mass conditions. Retrievals of microphysical properties of the haze from the Raman lidar indicated distinct light-absorbing characteristics for different haze aerosols originating from eastern and northern China (haze) and eastern Siberia (forest-fire smoke). The haze transported from the west showed moderately higher absorbing characteristics (SSA = 0.90 ± 0.03, 532 nm) than from the northern direction (SSA = 0.96 ± 0.02). The organic/elemental carbon (OC/EC) ratio varied between 2.5 ± 0.4 and 4.1 ± 0.7.  相似文献   
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Bladder outlet obstructions are a diverse and heterogeneous group of developmental abnormalities that generally involve obstruction of the proximal urethra in the male fetus. Indications for prenatal intervention are few and are usually restricted to the male fetus because bladder outlet obstruction in female fetuses is usually caused by complex cloacal development anomalies. We report on a female fetus with an enlarged bladder and a dilated proximal urethra (known as typical keyhole sign). A vesicoamniotic shunt was performed despite non-reassuring prognostic factors, but the procedure resulted in a successful outcome. We propose that in selected cases of bladder outlet obstruction, fetal intervention should be considered even when the fetus is female. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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Journal of Material Cycles and Waste Management - The ilmenite-chloride process has used for the production of TiCl4 from the ilmenite (FeTiO3) ore, which produces cyclone dust containing mostly...  相似文献   
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