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321.
Paula Guedes Nazaré Couto Joana Almeida António M. Rodrigues Eduardo P. Mateus Alexandra B. Ribeiro 《International Journal of Environmental Science and Technology》2018,15(5):1103-1112
This study aimed to evaluate the changes in microbiological communities present in sewage sludge (SS) when subjected to an electric field. The establishment of these relations is important to design and optimize an electrotechnology that not only promotes a direct degradation of the emerging organic contaminants, through electrodegradation, but also stimulates their biodegradation. Different current intensities were used continuously or by steps, in a two compartment electrodialytic (ED) cell. Samples collected between May and July of 2015 were analysed, prior to ED treatment, and the 35 Taxa identified were divided in 12 groups. Initial samples, collected on May, were mainly constituted by stalked ciliates (86%), followed by shelled amoebae (8%), whereas the samples collected between June and July presented higher number of shelled amoebae, between 52 and 92%. Epistylis, Vorticella and Arcella gibbosa were the most frequent protozoa identified. Samples richness (R) was between 7 and 14, Simpson’s biodiversity index (D) between 0.45 and 0.69, and evenness between 0.42 and 0.65. At the end of the ED experiments, a decrease in the number of identified Taxa and individuals was observed and, consequently, SS biodiversity also decreased. This decline was more pronounced in the ED experiments conducted with currents above 50 mA (0.10 mA cm?2). In terms of abundance, the final SS was mainly constituted by shelled amoebae that showed to be the most resistant to the conditions within the ED cell. The obtained results showed that the studied conditions within the ED cell were not appropriate to the microbiological communities, which influenced the final SS quality. 相似文献
322.
Cristiane Bahi dos Santos-Fischer Jair Weschenfelder Iran Carlos Stalliviere Corrêa Jeffery Robert Stone Beatriz Appel Dehnhardt Eduardo Calixto Bortolin 《Estuaries and Coasts》2018,41(6):1601-1625
Drowning of the coast was initiated by a marine inundation after the Last Glacial Maximum (marine isotope stage (MIS) 2) and has continued during the mid-Holocene and highstand (MIS 1). Detailed analyses of two previously examined core stratigraphy and seismic profiles combined with new grain-size and detailed diatom analyses are used to study the history of the Barra Falsa paleochannel over the last 11,000 years BP and to document the peculiar deposition within the channel fill. A rapid sea-level rise was responsible for flooding the coast in 11,180–10,780, 8420–7930, 8150–7870, and 7640–7430 cal years BP, infilling a low topographic back-barrier region. High deposition rates suggest a rapid filling of the channel, which coincides with an accelerated period of sea-level rise, closely linked to the global 8.2-ka event. The morphology of the channel is recognized by facies units in the underlying strata related to one episode of cut and fill during a single cycle of base-level fall and rise. An overall transgressive sequence above the regional surface is related to marine and marine-brackish sediments, which corresponds to a seaward/central basil fill of a wave-dominated estuary. 相似文献
323.
Jorge A. Salinas-Jasso Juan C. Montalvo-Arrieta Eduardo Reinoso-Angulo 《Landslides》2018,15(4):783-795
Landslides caused by a low magnitude earthquake swarm (2.8?≤?M?≤?3.6) in 2012 were documented at the Santa Rosa Canyon in northeastern Mexico. Disrupted landslides from falls and slides, in both rocks and soils, were identified based on fieldwork and high-resolution satellite imagery along stream banks from natural cliffs and along the road cut in the epicentral area. Most of the landslides occurred on slopes greater than 40°, where geological features played a key role in triggering slope instabilities. The maximum distance limit for disrupted slides from the epicentral area was 7 km. The area affected by landslides during the early stage of the seismic sequence (July through August 2012) was 90 km2. Landslide identification was limited in some areas by the resolution of the satellite imagery and dense cloud coverage. Both the epicentral distance and the area affected by landslides are above the global bounds reported in literature. The final landslide inventory is the first documented case of earthquake-induced landslides in northeastern Mexico. 相似文献
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326.
Jaime Horta Eduardo Rojas María L. Pérez‐Rea Teresa López Juan B. Zaragoza 《国际地质力学数值与分析法杂志》2013,37(8):932-944
This paper describes a random solid‐porous model capable of simulating the structure of porous materials. To this purpose, the grain and pore size distributions as well as the void ratio of the material are required. Solids and pores are distributed at random in the model's space according to a size strategy. Herein, the model is used to simulate the retention curves of soils. The Laplace equation is used to determine the size of the pores able to saturate or dry during a wetting or drying process, respectively. The continuous path principle is used to define those elements that effectively saturate or dry during these processes. With this procedure, it is possible to simulate the main retention curves as well as the scanning curves during wetting–drying cycles. Some experimental results reported in the international literature have been used to test the model. This model can be enhanced to study the mechanical behavior of unsaturated soils. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
327.
J. Eduardo Vaz 《Meteoritics & planetary science》1972,7(2):77-86
Analyses of the variation of the natural thermoluminescece output with depth from the final surface of the Ucera (Venezuela) meteorite have shown that the specimen was not uniformly heated by friction in the atmosphere during its fall. The results of the measurement performed on material removed from different areas around the midsection of the stone, are in good agreement with what can be inferred from the morphological features of the aerodynamically shaped specimen. 相似文献
328.
The nearby (d=5.0 pc) brown dwarf LP 944-20 was observed with the XMM-Newton satellite on 07 January 2001. The target was detected with the Optical Monitor (V=16.736±0.081), but it was not detected during the ≈48 ks observation with the X-ray telescopes. We determine a 3σ upper limit for the X-ray emission from this object of LX<3.1×1023 ergs·s−1, equivalent to a luminosity ratio upper limit of log(LX/Lbol)≤−6.28. This measurement improves by a factor of three the previous Chandra limit on the quiescent X-ray flux. This is the most sensitive limit ever obtained on the quiescent X-ray emission of a brown dwarf. Combining the XMM-Newton data with previous ROSAT and Chandra data, we derive flare duty cycles as a function of their luminosities. We find that very strong flares [Log(LX/Lbol)>−2.5] are very rare (less than 0.7% of the time). Flares like the one detected by Chandra [Log(LX/Lbol)=−4.1] have a duty cycle of about 6%, which is lower than the radio flare duty cycle (13%). When compared with other M dwarfs, LP 944-20 appears to be rather inactive in X-rays despite of its relative youth, fast rotation and its moderately strong activity at radio wavelengths. 相似文献
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330.
HU Xiumian WANG Jiangang Marcelle BouDagher-Fadel Eduardo Garzanti WEI An 《《地质学报》英文版》2013,87(Z1):27-28