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241.
S. Hellsten U. Dragosits C. J. Place T. H. Misselbrook Y. S. Tang M. A. Sutton 《Water, Air, & Soil Pollution: Focus》2007,7(1-3):3-13
Most ammonia (NH3) emission inventories have been calculated on an annual basis and do not take into account the seasonal variability of emissions
that occur as a consequence of climate and agricultural practices that change throughout the year. When used as input to atmospheric
transport models to simulate concentration fields, these models therefore fail to capture seasonal variations in ammonia concentration
and dry and wet deposition. In this study, seasonal NH3 emissions from agriculture were modelled on a monthly basis for the year 2000, by incorporating temporal aspects of farming
practice. These monthly emissions were then spatially distributed using the AENEID model (Atmospheric Emissions for National
Environmental Impacts Determination). The monthly model took the temporal variation in the magnitude of the ammonia emissions,
as well as the fine scale (1-km) spatial variation of those temporal changes into account to provide improved outputs at 5-km
resolution. The resulting NH3 emission maps showed a strong seasonal emission pattern, with the highest emissions during springtime (March and April) and
the lowest emissions during summer (May to July). This emission pattern was mainly influenced by whether cattle were outside
grazing or housed and by the application of manures and fertilizers to the land. When the modelled emissions were compared
with measured NH3 concentrations, the comparison suggested that the modelled emission trend corresponds fairly well with the seasonal trend
in the measurements. The remaining discrepancies point to the need to develop functional parametrisations of the interactions
with climatic seasonal variation. 相似文献
242.
The investigation of 5547 prenatal diagnoses showed 31 unexpected structural chromosome rearrangements. These included 3 Robertsonian translocations, 14 reciprocal translocations and 14 inversions. A11 were balanced, including 5 de novo rearrangements. In 3 of these cases an induced abortion was performed and in 2 cases children without detectable malformations were delivered. 相似文献
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244.
Ken Inoue Makoto Kanai Yuzo Tanabe Takeo Kubota Catherine D. Kashork Keiko Wakui Yoshimitsu Fukushima James R. Lupski Lisa G. Shaffer 《黑龙江环境通报》2001,21(13):1133-1136
A submicroscopic genomic duplication in Xq22.2 that contains the entire proteolipid protein 1 gene (PLP1) is responsible for the majority of Pelizaeus–Merzbacher disease (PMD) patients. We previously developed an interphase FISH assay to screen for PLP1 duplications in PMD patients using peripheral blood and lymphoblastoid cell lines. This assay has been utilized as a clinical diagnostic test in our cytogenetics laboratory. To expand usage of the interphase FISH assay to prenatal diagnosis of PLP1 duplications, we examined three PMD families with PLP1 duplications utilizing aminiotic fluid samples. In two families the FISH assay revealed fetuses with PLP1 duplications, whereas the other fetus showed a normal copy number of PLP1. Haplotype analyses, as well as an additional FISH analysis using postnatal blood samples, confirmed the results of the prenatal analyses. Our study demonstrates utility of the interphase FISH assay in the prenatal diagnosis of PLP1 duplications in PMD. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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247.
废高磁合金钢中钴、镍的分离和利用 总被引:1,自引:0,他引:1
用硫酸、盐酸和硝酸溶解废高磁合金钢、并将Fe^2 氧化为Fe^3 。先用黄铁矾法除去大部分铁,用尿素除去少量的铁及铝、钛、铜;最后在NH3-NH4Cl体系中分离钴、镍,并制成相应的盐。钴、镍的回收率分别国81.5%、89.7%。 相似文献
248.
V. N. Pozolotina 《Russian Journal of Ecology》2001,32(2):102-109
Local dandelion (Taraxacum officinales.l.) populations were studied in the areas of the Eastern Ural Radioactive Trace and the floodplain of the Techa River in its upper reaches. In impact plots, the density of soil and plant cover contamination with 90Sr and 137Cs exceeded the background level by factors of 13–440 and 2–500, respectively; the radiation load exceeded the background level by factors of 1.5 to 45. The seed progeny of plants from these plots was characterized by a high proportion of abnormal seedlings and an increased level of chromosome aberrations in meristem cells. In some years, variation in the seedling viability, growth rate, and developmental rate in these plots exceeded the reaction norm of plants from the background plot, demonstrating both stimulation and inhibition of growth processes. The response of seeds to acute irradiation at high challenging doses varied depending on the level of background radiation in the plots. 相似文献
249.
Spraying water under high pressure generates charge-separating processes. While cleaning tanks and vessels in which an explosive atmosphere is present, an explosion may occur in the event of a resulting discharge. Water forms electrical double layers at the phase boundaries. Mechanical separation processes dissolve the water into many drops. This leads to charge separation and the charging of the sprayed water. The mechanical separation processes include water exiting from the nozzle, hydrodynamic instability in the jet and impact with an obstacle. Given that water has many charge carriers, the charge is stronger than with solvents. Whether the charges and the resulting discharges are potentially capable of igniting an explosive atmosphere must be investigated. The aim of this research is to define the quantity and polarity of the electrostatic charges of sprayed water under high pressure. Different measurement techniques and methods are used to enable mutual validation and to generate verified measurement results of the electric field and the potential. Water of different electrical conductivity is sprayed in free space and into a grounded conductive 1 m3 vessel. Design changes to the vessel allow centric or oblique spraying. The result is intended to extend the scope of application of the German regulation TRGS 727 and the international IEC TS 60079-32-1, which refer to ignition hazards due to electrostatic charging. This project is funded by the DGUV (German Social Accident Insurance) and partners from industry. 相似文献
250.
Safety studies for production and use of hydrogen reveal the importance of accurate prediction of the overpressure effects generated by delayed explosions of accidental high pressure hydrogen releases. Analysis of previous experimental work demonstrates the lack of measurements of turbulent intensities and lengthscales in the flammable envelope as well as the scarceness of accurate experimental data for explosion overpressures and flame speeds. AIR LIQUIDE, AREVA STOCKAGE ENERGIE and INERIS join in a collaborative project to study un-ignited and ignited high pressure releases of hydrogen.The purpose of this work is to map hydrogen flammable envelopes in terms of concentration, velocity and turbulence, and to characterize the flame behaviour and the associated overpressure. These experimental results (dispersion and explosion) are also compared with blind FLACS modelling. 相似文献