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91.
Electromagnetic field (EMF) measurements, for labor safety and environment protection purposes, are performed in the near-field.
Inaccuracy of the far-field EMF measurements oscillates around ±1 dB or bit worse; in the near-field measurements, errors
at the level of ±6 dB must be sometimes accepted. In the case of non-stationary EMF measurements, their sense may be changed
from quantitative to qualitative ones. In order to make it possible an estimation of the non-stationary EMF measurement accuracy,
it is proposed new method of the meters calibration. The method is based upon a standard excitation with identical signal
as the measured one. A set for the purpose includes a pulse generator (of frequency and pulse rating identical with the radiation
source) and computer-controlled amplitude modulator that reflects the radiation pattern of an antenna (e.g. radar one) and
its rotations. Contrary to calibration using monochromatic continuous wave (CW) excitation, proposed method should be repeated
for any radiation source. The disadvantage is compensated by a possibility to estimate (additional) error of the method. Calculations
show it at the level of 10%. 相似文献
92.
Combining steam injection with hydraulic fracturing for the in situ remediation of the unsaturated zone of a fractured soil polluted by jet fuel 总被引:1,自引:0,他引:1
Nilsson B Tzovolou D Jeczalik M Kasela T Slack W Klint KE Haeseler F Tsakiroglou CD 《Journal of environmental management》2011,92(3):695-707
A steam injection pilot-scale experiment was performed on the unsaturated zone of a strongly heterogeneous fractured soil contaminated by jet fuel. Before the treatment, the soil was stimulated by creating sub-horizontal sand-filled hydraulic fractures at three depths. The steam was injected through one hydraulic fracture and gas/water/non-aqueous phase liquid (NAPL) was extracted from the remaining fractures by applying a vacuum to extraction wells. The injection strategy was designed to maximize the heat delivery over the entire cell (10 m × 10 m × 5 m). The soil temperature profile, the recovered NAPL, the extracted water, and the concentrations of volatile organic compounds (VOCs) in the gas phase were monitored during the field test. GC-MS chemical analyses of pre- and post-treatment soil samples allowed for the quantitative assessment of the remediation efficiency. The growth of the heat front followed the configuration of hydraulic fractures. The average concentration of total hydrocarbons (g/kg of soil) was reduced by ~ 43% in the upper target zone (depth = 1.5-3.9 m) and by ~ 72% over the entire zone (depth = 1.5-5.5 m). The total NAPL mass removal based on gas and liquid stream measurements and the free-NAPL product were almost 30% and 2%, respectively, of those estimated from chemical analyses of pre- and post-treatment soil samples. The dominant mechanisms of soil remediation was the vaporization of jet fuel compounds at temperatures lower than their normal boiling points (steam distillation) enhanced by the ventilation of porous matrix due to the forced convective flow of air. In addition, the significant reduction of the NAPL mass in the less-heated deeper zone may be attributed to the counter-current imbibition of condensed water from natural fractures into the porous matrix and the gravity drainage associated with seasonal fluctuations of the water table. 相似文献
93.
Rygula A Jekiel K Szostak-Kot J Wrobel TP Baranska M 《Journal of environmental monitoring : JEM》2011,13(11):2983-2987
In this work we present the usefulness of FT-Raman spectroscopy for microbiological analysis of textiles. This technique was used for non-destructive identification of Escherichia coli bacteria on cotton and polyester fabrics. It was possible to discriminate between infected and non-infected materials. Moreover, this technique allowed detection of detergent traces as well as investigation of the influence of microorganisms on different textiles. Raman analysis supported by chemometrics (cluster analysis and principal component analysis) was shown to be a method for identification of textiles with inoculum of microorganisms in a short time. The results can be potentially used in the fabric industry and related areas. 相似文献
94.
Johann Sarah Goßen Mira Mueller Leonie Selja Valentina Gustavson Kim Fritt-Rasmussen Janne Wegeberg Susse Ciesielski Tomasz Maciej Jenssen Bjørn Munro Hollert Henner Seiler Thomas-Benjamin 《Environmental science and pollution research international》2021,28(13):16198-16213
Environmental Science and Pollution Research - In situ burning (ISB) is discussed to be one of the most suitable response strategies to combat oil spills in extreme conditions. After burning, a... 相似文献
95.
Tomasz Ciach Tomasz R. Sosnowski 《International journal of occupational safety and ergonomics》2013,19(3):321-333
The paper presents results of investigations of a novel method for diesel exhaust filtration in a fibrous filter supplemented by the external electrostatic field (FEF), which may be used to eliminate the occupational hazard near sources of diesel emission. The reported research follows the preliminary basic study of soot removal in such systems (Ciach, Sosnowski, & Podgórski, 1995), and is focused on the construction and testing of a prototype technical-scale FEF device. The results suggest a strong relation between applied voltage and filtration efficiency of the system and demonstrate the influence of aerosol precharging on the efficiency, which can be more than 95%. 相似文献
96.
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98.
Treatment of high-ammonium anaerobic digester supernatant by aerobic granular sludge and ultrafiltration processes 总被引:1,自引:0,他引:1
Agnieszka Cydzik-Kwiatkowska Magdalena Zielińska Katarzyna Bernat Irena Wojnowska-Baryła Tomasz Truchan 《Chemosphere》2013,90(8):2208-2215
Anaerobic sludge digester supernatant characterized by 569 mg TKN L?1, high color and a COD/N ratio of 1.4 was treated in granular sequencing batch reactors (GSBRs) followed by post-denitrification (P-D) and ultrafiltration (UF) steps. The use of granular sludge allowed for the oxidation of ammonium in anaerobic digester supernatant at all investigated GSBR cycle lengths of 6, 8 and 12 h. The highest ammonium removal rate (15 mg N g?1 VSS h?1) with removal efficiency of 99% was noted at 8 h.Since the GSBR effluent was characterized by a high concentration of nitrites, slowly-degradable substances and biomass, additional purification steps were applied. In P-D stage, the microbial activity of granular biomass in the GSBR effluent was implemented. The P-D was supported by external carbon source addition and the most advantageous variant comprised dosing of half of the theoretical acetate dose for nitrite reduction in the 3-h intervals. The use of the system consisting of the GSBR with 8 h, an optimal P-D variant and a UF for the treatment of anaerobic digester supernatant allowed for the 99%, 71% and 97% reductions of TKN, COD and color, respectively. 相似文献
99.
Mostrąg Aleksandra Puzyn Tomasz Haranczyk Maciej 《Environmental science and pollution research international》2010,17(2):470-477