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21.
Rai S. Kookana Ali Shareef Milena B. Fernandes Sonja Hoare Sam Gaylard Anu Kumar 《Marine pollution bulletin》2013
The anti-microbial agent triclosan (TCS), and its derivative methyl-triclosan (Me-TCS), are discharged with treated effluents from wastewater treatment plants to receiving environments. We investigated the bioconcentration of TCS and Me-TCS in mussels (Mytilus galloprovincialis) exposed to TCS (100 ng L−1) for 30 days in seawater aquaria (19 ± 2 °C) with fresh phytoplankton as a food source. Bioconcentration increased with time reaching a steady-state around 24–30 days. The bioconcentration factor (log BCF) for TCS were 2.81 L kg−1 (dry weight) and 4.13 L kg−1, when lipid normalised concentrations were used. Mussels were also deployed in cages at four marine locations receiving effluents from WWTPs. The mean (±SD) TCS and Me-TCS concentrations for mussels from these sites were 9.87 (±1.34) and 6.99 (±2.44) μg kg−1. The study showed that mussels can be a useful tool for monitoring pollution of TCS and Me-TCS in marine and estuarine environments. 相似文献
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23.
We present results for the global elastic parameters (k
2, k
3) and (h
2, l
2) derived from the analysis of Satellite Laser Ranging (SLR) data. The SLR data for two satellites, LAGEOS 1 and LAGEOS 2,
collected over a period of two years, from 1 January 2005 to 1 January 2007, from 18 globally distributed ground stations
are analyzed using different approaches. The analysis is performed for the two satellites jointly, and the four elastic parameters
are estimated. We carry out a sequential analysis and study the stability of the estimates as a function of the length of
the data set used. The adjusted final values for k
2 (0.3011±0.0001) and k
3 (0.0896±0.0037) and those for h
2 (0.6146±0.0006) and l
2 (0.0883±0.0003) for LAGEOS 1 and LAGEOS 2 tracking data are compared to the estimates derived in other studies. 相似文献
24.
Milena Arias Schreiber 《Marine Policy》2012,36(1):78-89
Landings statistics of the Peruvian anchovy fishery show that the fishery went through a phase of explosive and uncontrolled growth from its establishment in the mid-fifties until its collapse in 1972. After the collapse, a second phase from 1973 to 1984 was characterized by unfavorable warm ocean conditions and low catches. A third phase, from 1984 to the present, with propitious ocean-environmental conditions and modern governance, can be further divided into a controlled growth period (1985-1994) and a sustainable landings' period (1995 to present). The most recent period of the third phase has enabled the fishery to maintain its catches and be labeled as one of the most sustainable fisheries worldwide. This article highlights the evolution of the legal system that provides for the current sustainable landings and governance of this fishery. Results show that General Fisheries Acts were enacted independently of failures to sustain anchovy landings. The three Peruvian Fisheries Acts were a reflection of broader national socio-political changes and were enacted mainly to define the role of the state and private investment and to delimit foreign involvement in the fishery industry. By contrast, the enactment of secondary legislation to control quotas and fishing seasons increased as the fishery moved towards stable landings. During this phase, enacted secondary legislation showed also a clear peak during strong positive sea surface anomalies driven by the El Niño Southern Oscillation (ENSO) 1997-1998, providing evidence of rapid adaptive management. The role of Fisheries Acts in defining access rights at the national level from a multilevel governance approach is discussed and further key elements that contributed to the transition towards sustainability are suggested. 相似文献
25.
Pedro L. Guzzo Helen J. Khoury Milena R. Miranda Sandra B. Barreto Armando H. Shinohara 《Physics and Chemistry of Minerals》2009,36(2):75-85
This paper discusses the structural features required to stimulate a strong thermoluminescence (TL) glow peak near 300°C in
clear natural quartz. For that reason, fresh TL data taken from several specimens prepared from five single crystals with
known impurity content are shown. The TL emission was measured with a test dose of 10 mGy of γ-rays in the readout intervals
50–160 and 160–320°C. The readings were carried out prior and after the administration of a pre-dose of 175 kGy of γ-rays
followed by heat-treatments at 400°C. For each single specimen, the OH content and the population of inclusions were evaluated
by infrared spectroscopy and optical microscopy, respectively. The darkening induced by high γ dose was evaluated by optical
spectroscopy. It was observed that the absorption at 475 nm and TL responses decrease with increase of the OH. It was shown
that both smoky darkening and TL signals were better explained in terms of Li/Al and Li/OH content ratios rather than the
absolute values of aluminum and alkali concentrations. The sensitization with high γ dose and heating is essential to create
and stabilize a class of defects sites with Li+ ions dislodged from [AlO4/Li]0 and Li-dependent OH centers. It is suggested that the defect sites formed with Li+ act as electron traps during test dose irradiation, whereas electron-hole recombination occurs essentially at [AlO4]0 centers during the TL output near 300°C. 相似文献
26.
V. Horvat 《Theoretical and Applied Climatology》1989,40(4):255-260
Summary The Yugoslavian hail-suppression system uses rockets with 0.4 kg of a pyrotechnical mixture which produces an AgI based aerosol by the process of burning. The activity of thus obtained aerosol is measured in several type cold chambers.Presented results were obtained at the Hydrometeorological Institute of Croatia (HIC), Zagreb, for the pyrotechnical mixtures R-32 (used from 1981 to 1988), VTG-8 (1986–1988), MKM-10 (used in 1989) and AJ (it will be used in year 1989).The activity of aerosol depends on several parameters, e.g. the type of burning and streaming, meteorological conditions and the time the aerosol remains in the cloud. Furthermore, the activity depends on the technological production process of the pyro-technical mixtures.The pyro-technical mixtures MKM-10 and AJ proved to be more active than the R-32 and VTG-8 in the interval from the threshold to –10°C, i.e. in the warm cloud area.
With 8 Figures 相似文献
Zusammenfassung Das jugoslawische Hagelabwehrsystem verwendet Raketen mit 0.4 kg eines pyrotechnischen Präparats, das bei Verbrennung Aerosole auf AgJ-Basis freisetzt. Die Wirkung dieser Aerosole wird in unterschiedlichen Typen kalter Nebelkammern gemessen. Die im Hydrometeorologischen Institut von Kroatien (HIC) in Zagreb erzielten Ergebnisse beziehen sich auf die pyrotechnischen Mischungen R-32 (in Verwendung von 1981 – 1988), VTG-8 (1986 – 1988), MKM-10 (1989) und AJ (wird erst 1989 verwendet).Die Wirkung des Aerosols ist von verschiedenen Parametern abhängig, so etwa von der Art der Verbrennung und der Strömung, von den meteorologischen Bedingungen und von der Verweildauer des Aerosols in der Wolke. Weiters hängt sie auch vom technischen Herstellungsprozeß der pyrotechnischen Mischung ab.Die pyrotechnischen Präparate MKM-10 und AJ haben sich im Intervall vom Gefrierpunkt bis –10°, also in den warmen Wolkenzonen, als wirksamer erwiesen als R-32 und VTG-8.
With 8 Figures 相似文献
27.
Gellrt Gligor Tams Szolnoky Milana Dra&#x;kovi&#x; Nenad &#x;uri&#x; Zdravko Hojka Jelena Bo&#x;kovi&#x; Milena
ua 《洁净——土壤、空气、水》2019,47(10)
Anaerobically stabilized sludge from wastewater treatment is always a challenge from the environmental aspect of management. The agrarian environmental surroundings present a possibility for swift and efficient utilization of compost from anaerobically stabilized sludge in order to increase the quality of the biological product. With intensification of the composting procedure by means of the microbiological consortium Geocell‐1 (Cellvibrio sp., Pseudomonas fluorescens with the addition of micro‐ and macro‐elements), the results show that the compost obtained from stabilized sludge after inoculation is significantly improved in terms of moisture reduction (39–43%), while in the control compost, this value is significantly higher with 61%. The results of the pathogenic effect show a significant reduction in the number of fecal coliform (<1 × 103) and Enterococcus bacteria (<1 × 104) in the inoculated (treated) compost. With a slight decrease in the concentration of limiting factors such as As, Cd, Cu, a quality biological product can be achieved, which can be safely deposited on soil. The phytotoxicological germination test with white mustard (Sinapis alba) shows a higher number of sprouting plants with a mixture of treated compost and standard soil for flowers 1:1 and 1:4 compared to the control group. 相似文献
28.
Jean Alberto Mensa Zulema Garraffo Annalisa Griffa Tamay Mehmet Özgökmen Angelique Haza Milena Veneziani 《Ocean Dynamics》2013,63(8):923-941
Frontogenesis and frontal instabilities in the mixed layer are known to be important processes in the formation of submesoscale features. We study the seasonality of such processes in the Gulf Stream (GS) region. To approach this problem, a realistic simulation with the Hybrid Coordinate Ocean Model is integrated for 18 months at two horizontal resolutions: a high-resolution (1/48°) simulation able to resolve part of the submesoscale regime and the full range of mesoscale dynamics, and a coarser resolution (1/12°) case, in which submesoscales are not resolved. Results provide an insight into submesoscale dynamics in the complex GS region. A clear seasonal cycle is observed, with submesoscale features mostly present during winter. The submesoscale field is quantitatively characterized in terms of deviation from geostrophy and 2D dynamics. The limiting and controlling factor in the occurrence of submesoscales appears to be the depth of the mixed layer, which controls the reservoir of available potential energy available at the mesoscale fronts that are present most of the year. Atmospheric forcings are the main energy source behind submesoscale formation, but mostly indirectly through mixed layer deepening. The mixed layer instability scaling suggested in the (Fox-Kemper et al., J Phys Oceanogr 38:1145–1165, 2008) parametrization appears to hold, indicating that the parametrization is appropriate even in this complex and mesoscale dominated area. 相似文献
29.
Fen ecosystem responses to water‐level fluctuations during the early and middle Holocene in central Europe: a case study from Wilczków,Poland 
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下载免费PDF全文 Mateusz Płóciennik Andrzej Kruk Jacek Forysiak Dominik Pawłowski Kamila Mianowicz Scott Elias Ryszard K. Borówka Marek Kloss Milena Obremska Marek Krąpiec Piotr Kittel Sławomir Żurek 《Boreas: An International Journal of Quaternary Research》2015,44(4):721-740
This paper presents a palaeoenvironmental reconstruction of the Wilczków fen (central Poland). The fen developed in an inactive valley at the onset of the Holocene (~11 ka BP) and peat accumulation lasted until 5.7 ka BP. Multi‐proxy reconstructions were made on the basis of palaeobotanical, cladoceran, chironomid, beetle and geochemical analyses. A Kohonen self‐organizing map (SOM, unsupervised artificial neural network) of the biotic sequence distinguished four stages of fen history. Stage X1 (11.0–10.7 ka BP) was relatively wet and cool. Organic matter started to accumulate but the habitat conditions remained unstable. Moss, sedge and fern communities then developed. Sedimentary changes reveal an intensive groundwater supply at that time. Numerous and diverse chironomid and cladoceran subfossils indicate nearly permanent aquatic conditions. During stage Y1 (10.6–9.2 ka BP) conditions were dry and the upper peat layer desiccated. Cladocera nearly disappeared whereas chironomids were represented by semi‐terrestrial and predatory (Tanypodinae) species. Conditions started to be more reducing. All the remaining samples belonged to the interweaving stages X2 and Y2. Stage Y2 (mostly 9.1–7.3 and 6.0–5.7 ka BP) was also dry but humidity increased towards the top. Oxidizing conditions occurred and the pH became more alkaline, favouring Cladium mariscus. The basin received mostly allochthonous matter input at that time. Stage X2 (mostly 6.8–6.1 ka BP) was humid and warm. The groundwater supply remained low but there was an increase in precipitation, changing local conditions to ombrotrophic. Species‐rich chironomid and cladoceran communities were associated with temporary pools. Finally, conditions returned to those characteristic of stage Y2. The presented reconstruction documents long‐term abiotic and biotic changes determined by water supply, including groundwater outflow, which have rarely been detected at a multi‐proxy scale. We show that inactivated valley fens are sensitive to climate‐driven hydrological fluctuations. Kohonen neural networks appear to be a promising method for analysing variability in multi‐proxy data. 相似文献
30.
High resolution Vp and Vp/Vs tomography of the Campi Flegrei caldera is obtained using active and passive seismic data. We find a continuous ring of high Vp anomaly that defines the caldera rim associated to the last collapse. A sharp Vp/Vs decrease is observed between 2 and 4 km depth, suggesting the absence of magmatic fluids and the presence of rock volumes with over‐pressured gas within the source region of uplift. Atmospheric water penetrating within the caldera and deep CO2 fluids are presumably heated by a magmatic body located at depth greater than 4 km nested within the limestone layer. Along the fractures bordering the shallow high Vp rim, deep gas and CO2 fluids up‐raise and are released in the Pozzuoli solfatara. We hypothesize that the past unrest episode is more likely due to pressure changes within the shallow geothermal reservoir located at the top of the magma intrusion. 相似文献