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This work describes the development of an urban vehicle emissions inventory for South America, based on the analysis and aggregation of available inventories for major cities, with emphasis on its application in regional atmospheric chemistry modeling. Due to the limited number of available local inventories, urban emissions were extrapolated based on the correlation between city vehicle density and mobile source emissions of carbon monoxide (CO) and nitrogen oxides (NOx). Emissions were geographically distributed using a methodology that delimits urban areas using high spatial resolution remote sensing products. This numerical algorithm enabled a more precise representation of urban centers. The derived regional inventory was evaluated by analyzing the performance of a chemical weather forecast model in relation to observations of CO, NOx and O3 in two different urban areas, São Paulo and Belo Horizonte. The gas mixing ratios simulated using the proposed regional inventory show good agreement with observations, consistently representing their hourly and daily variability. These results show that the integration of municipal inventories in a regional emissions map and their precise distribution in fine scale resolutions are important tools in regional atmospheric chemistry modeling.  相似文献   
3.
The removal of trans-chlordane (C(10)H(6)Cl(8)) from aqueous solutions was studied using UV, UV/H(2)O(2), UV/H(2)O(2)/Fe(2+), UV/TiO(2), or UV/TiO(2)/H(2)O(2) treatment using either UV/Vis blue lamps or UVC lamps (254 nm). H(2)O(2), FeSO(4) and TiO(2) were added at 1700, 456, and 2500 mgL(-1), respectively. trans-Chlordane was not significantly removed in non-irradiated controls and in samples irradiated with UV/Vis. It was also not removed in the absence of surfactant Triton X-114 added at 250 mgL(-1). In the presence of the surfactant, trans-chlordane concentration was reduced by 95-100% after 48 h of UVC and UVC/H(2)O(2) treatments and 70-80% after UVC/H(2)O(2)/Fe(2+), UVC/TiO(2) and UVC/H(2)O(2)/TiO(2) treatments. Based on these results, UVC, UVC/H(2)O(2) and UVC/TiO(2) treatments were further investigated. UVC treatment supported the highest pollutant removal (100% in 48 h), dechlorination efficiency (81% in 48 h), and detoxification to Lepidium sativum seed germination and activated sludge respiration although irradiated samples remained toxic to Chlorella vulgaris. Biodegradation of the UVC irradiated samples removed the source of algae toxicity but this could not be clearly attributed to the removal of trans-chlordane photoproducts because the surfactant interfered with the chemical and biological assays. Evidence was found that trans-chlordane was photodegraded through photolysis causing its successive dechlorination. trans-Chlordane removal was well described by a first order kinetic model at a rate of 0.21±0.01h(-1) at the 95% confidence interval.  相似文献   
4.
Abstract

Land disposal of olive oil wastewater using it as a soil amendment requires a knowledge of the effects that its application may produce on the status of the mineral nutrients in the plant‐soil system. A pot experiment using calcareous soil was performed in a growth chamber to examine the effects of olive oil wastewater on the availability and postharvest soil extractability of K, Mg and Mn. The experiment included 6 treatments: two rates of olive oil wastewater, two mineral fertilizer treatments containing K (which supplied K in amounts equivalent to the K supplied by the olive oil wastewater treatments), a K‐free mineral fertilizer treatment, and a control. The pots were sown with ryegrass as the test plant, harvesting 3 times at intervals of one month. Olive oil wastewater has demonstrated a considerable capacity for supplying K that can be assimilated by the plant, tending in fact to surpass the mineral potassium fertilizer tested. The application of olive oil wastewater tends to reduce the concentration of Mg in the plant, similarly to the effect of adding mineral potassium fertilizer. An enhancement of Mn availability takes place in the soil amended with olive oil wastewater, which on occasion has produced Mn concentrations in plant that could be considered phytotoxic or at least excessive. After harvesting, we observed an increase in the amount of exchangeable K in soil with added industrial wastewater. However, these increases are lower than those in soil treated with mineral potassium fertilizer. The levels of exchangeable, carbonate‐bound, organic‐bound and residual Mg in soil were higher in treatments incorporating olive oil wastewater than in those with added mineral K, with the opposite tendency occurring in the amount of Fe‐Mn oxides‐bound Mg in soil. Treatments based on olive oil wastewater, especially in high doses, increased the amount of exchangeable and carbonate‐bound Mn in soil, in comparison with treatments adding mineral fertilizers with or without K. In contrast, the addition of industrial wastewater caused a drop in the amount of Fe‐Mn oxides‐bound and organic‐bound Mn in soil.  相似文献   
5.
The present study was undertaken to determine the effects of both extracapsular oxygen concentration and temperature on embryonic development in Chorus giganteus. In normoxia increasing water temperature from 12°C to 18°C reduced by 15 days the median time required for the capsules to hatch. Hypoxia (oxygen content at 50% of air saturation) generated a low development rate and totally prevented both shell secretion and larval hatching from the egg capsule. Experimental transfer at weekly intervals, from normoxia to hypoxia and vice versa, induced a decrease and increase in the embryonic ash content, respectively, but did not affect the number of hatched larvae. Such an effect was more pronounced at 12°C than at 15°C or 18°C. The embryonic inability to produce a shell under hypoxia is likely to be a result of the low intracapsular oxygen concentration (IPO2) generated as the combined effect of a low extracapsular oxygen concentration (environmental) added to the intracapsular embryonic oxygen demands, which lowers the IPO2 still further. Under such conditions, a decrease in intracapsular pH is likely to take place, and, if so, embryos might divert carbonates away from shell calcification to balance such changes in pH.  相似文献   
6.
Oviposition and embryonic-larval development are described for the muricacean snail Thais (Stramonita) chocolata from the Southeast Pacific coast. As with numerous other muricacean snails, this species engages in communal egg laying, with females depositing egg capsules in clusters on subtidal rocks. Each cluster of capsules contains 100–150 pedunculate, ampulliform egg capsules, with each capsule containing an average of 2,600 small (130 m) eggs. Intracapsular development was followed using light and scanning electron microscopy to describe the successive embryonic stages of the species. Free-swimming veliger larvae of about 225 m length were released from capsules after 49 days incubation at 13.6°C. The planktotrophic larvae were cultured in seawater aquaria by feeding with pure cultures of phytoplankton, recording growth and form of the larvae. Larvae reached competence after 4 months at 22°C, at 1,450–1,740 m in size, and a few larvae were observed through metamorphosis and early definitive growth. The embryonic-larval development of T. chocolata coincides with the general characteristics of the ontogeny observed in other Thais species as well as of other genera of the Rapaninae such as Concholepas. This lent support to grouping these genera into a single clade. The lack of knowledge of the development of free larvae of Thais spp. means that we do not know whether these similarities also include an extensive larval phase as generally characteristic of other members of the clade. The mode of development may be useful in characterizing some clades of this family. Thus for example, the transference of some Thais to the genus Nucella (Subfamily Ocenebrinae) is supported by differences in the mode of embryonic development, which differentiates these subfamilies. Paleobiological data reported for Neogastropoda allow postulation of primitiveness in planktotrophic larval development compared to more recent developmental strategies such as direct development of different types, which characterize various clades of this family.Communicated by O. Kinne, Oldendorf/Luhe  相似文献   
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8.
In this study, spent compact fluorescent lamps were characterized to determine the distribution of mercury. The procedure used in this research allowed mercury to be extracted in the vapor phase, from the phosphor powder, and the glass matrix. Mercury concentration in the three phases was determined by the method known as cold vapor atomic absorption spectrometry. Median values obtained in the study showed that a compact fluorescent lamp contained 24.52±0.4ppb of mercury in the vapor phase, 204.16±8.9ppb of mercury in the phosphor powder, and 18.74±0.5ppb of mercury in the glass matrix. There are differences in mercury concentration between the lamps since the year of manufacture or the hours of operation affect both mercury content and its distribution. The 85.76% of the mercury introduced into a compact fluorescent lamp becomes a component of the phosphor powder, while more than 13.66% is diffused through the glass matrix. By washing and eliminating all phosphor powder attached to the glass surface it is possible to classified the glass as a non-hazardous waste.  相似文献   
9.
In Chinquihue Bay, a sheltered locality in Southern Chile, female Crepidula dilatata Lamarck brood egg masses which differ in intracapsular development. In some, all eggs develop and are hatched as free veliger larvae (indirect development). In others, only some of the eggs develop and hatch as young adults (direct development), the rest being consumed as nurse eggs. Two possible interpretations are considered: intrapopulation variation of developmental pattern in a species, and the coexistence of two sibling species. Stages of the intracapsular development are described and illustrated. Fecundity varies according to size of the female. For females brooding eggs with indirect development it is estimated at between 3840 and 85575 embryos per spawn; for females with eggs undergoing direct development, embryo production per egg mass is estimated at between 70 and 812. A comparison is made between females brooding the two kinds of egg masses. Minor differences exist in adult coloration, shape of egg capsules, egg diameters, spawning season and their abundance and distribution in the intertidal. Brooding females with eggs displaying indirect development are significantly larger than those with eggs of direct development. The latter females form chains subtidally but not intertidally as do females bearing eggs with indirect development. On these females with pelagic larvae, chains frequently include sedentary males which reach large sizes. On basal females with direct development, chains contain mostly other females, suggesting that matings are temporary and by errant males. These results are compared with existing information in the literature for other species both in this genus and in other marine invertebrates. It is concluded that two sympatric sibling species with different modes of development are present in the morphospecies C. dilatata Lamarck in Southern Chile.Devoted to Dr. E.F. Kilian, Zoologisches Institut der Universität Gießen, FRG.  相似文献   
10.
This study integrates procedures of ISO14001 and port state control to establish environmental performance indicators (EPIs), specific to industrial ports and estates. Industrial Estate Authority of Thailand (IEAT), an owner of Map Ta Phut industrial port and estate, was used as a case study. Twelve EPIs were developed to assess 5 environmental management aspects being success, awareness, determination, preparedness, and environmental policy coverage. IEAT's deficiencies in managing the environment were identified for each management aspect. At the end of the study, suggestions on how to improve IEAT's environmental performance were recommended.  相似文献   
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