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Sampling and analysis of litterfall 全文
2010
Pitman , Rona | Bastrup-Birk , Anne-Marie | Breda , Nathalie (INRA , Champenoux (France). UMR 1137 Ecologie et Ecophysiologie Forestières) | Rautio , Pasi
Implementation of the selective collection in small villages of less than 50 inhabitants in Cantabria region (Spain): Preliminary viability study 全文
2010
Margallo Blanco, María | Aldaco García, Rubén | Bala Gala, Alba | Fullana i Palmer, Pere | Irabien Gulías, Ángel | Universidad de Cantabria
This project develops an algorithm for allowing municipalities of dispersed villages of Cantabria, an Autonomous Community situated in the north coast of Spain, to check the environmental feasibility of extending the selective collection in their municipalities. The algorithm will allow these municipalities to introduce their own data and compare two waste management systems (Scenario A and B). Scenario A is referred to the current waste management system in which no selective collection is being carried out. Consequently, light packaging material (LP) and paper and cardboard (P/C) are collected together with the municipal solid wastes (MSW), following the same path. Scenario B is the hypothetic new waste management system in which selective collection is introduced. To determine the environmental preference of these scenarios, an algorithm based on Life Cycle Assessment (LCA) has been developed. Only if environmental impacts in Scenario B are lower than in A when running the model the extension of the selective collection for each individual municipality should be recommended.
显示更多 [+] 显示较少 [-]Impact analysis of the Spanish electric energy market liberalization on Chlor-alkali industry 全文
2010
Aldaco García, Rubén | Onandía de Dios, Raquel | Irabien Gulías, Ángel | Universidad de Cantabria
A sodium chloride solution is decomposed electrolytically to generate gaseous chlorine, sodium hydroxide and hydrogen. Electricity accounts for about 50 % of total production cost. In Spain, the Electrical Sector Act 54/1997 commenced the electric market liberalization, with the introduction into national laws the provisions contained in European Directive 96/92/EC. In July 2008, tariffs disappear for industry consumers. Hourly discrimination complement, given by tariffs, it has been an important energy costs optimization way for chlor-alkali industry and now it is not so evident the modulation advantage. This article tries to analyze impacts in chlor-alkali industry of this new electric markett.
显示更多 [+] 显示较少 [-]Desulfurization behaviour of CaCO3 added during the calcination of wastewater sludge at 900º C: reuse of the ash after reactivation 全文
2010
Renedo Omaechevarría, Josefina | Fernández Ferreras, Josefa | Universidad de Cantabria
In the present work dry sewage sludge from a local municipal wastewater plant, has been incinerated at 900 º C with CaCO3 added at two sludge/CaCO3 ratios: 10 sludge /1 CaCO3 or 10 sludge /10 CaCO3 in weight. The ability of this salt to capture the SO2 produced during the incineration is studied. The SO2 captured is quantified as mole SO2 / mole of Ca. Results shows that the amount of SO2 captured /mole of CaCO3, is much higher at the 10 sludge /1 CaCO3 ratio. With the resulting ashes, reactivated at different ways, desulfurant sorbents were prepared and essayed in a desulfurization process at low temperature. Results of the process at low temperature showed that the highest value of SO2 captured was found with the sorbent coming from the ashes obtained from the mixture 10 sludge /1 CaCO3 and reactivated by hydration at room temperature.
显示更多 [+] 显示较少 [-]Photovoltaic Solar Electrochemical Oxidation (PSEO) for lignosulfonate waste water treatment 全文
2010
Domínguez Ramos, Antonio | Aldaco García, Rubén | Irabien Gulías, Ángel | Universidad de Cantabria
Under the current global energy scenario, the need of self-sustainable processes is encouraged. A process of Photovoltaic Solar powered Electrochemical Oxidation (PSEO) has been developed to remove the organic matter from lignosulfonate waste water. Experimental results show that the process is able to oxidize the organic matter up to removal yields around 90% of Total Organic Carbon (TOC) under the described operating conditions, demonstrating the technical suitability of the PSEO process.
显示更多 [+] 显示较少 [-]Regulated metal levels in particulate matter in the Cantabria region (Northern Spain) using multivariate linear regression (MLR) 全文
2010
Arruti Fernández, Axel | Fernández Olmo, Ignacio | Irabien Gulías, Ángel | Universidad de Cantabria
The levels and chemical composition of the particulate matter (PM) are linked to the effects of this atmospheric pollutant on human health. An assessment of the PM levels and its constituents present in the atmosphere is an important requirement of the air quality management and air pollution abatement. Taking into account that (i) EC Directives allow the Regional Government to assess the air quality by objective estimation and modelling techniques and (ii) the experimental effort required in the analysis of heavy metals in air, the present work aims to estimate the annual levels of the heavy metals regulated by the EC Directives (Pb in 1999/30/EC, and As, Ni and Cd in 2004/107/EC) in PM10 by means of multivariate linear regression (MLR). The main results show that although important deviations are found for individual measurements, the 2008 annual average metal concentrations are well estimated by the MLR technique at the studied areas. So, these estimations may be used by Regional Governments for the level assessment of regulated metals when their concentrations are below the lower assessment threshold | The authors would like to thank the Spanish Ministry of Education and Science (CTM2006-00317) and the Government of Cantabria (“Actions for improving the air quality and its diagnosis in Cantabria”) for their funding.
显示更多 [+] 显示较少 [-]Recovery from Mercury Contamination in the Second Songhua River, China 全文
2010
Zhang, Z. S. | Sun, X. J. | Wang, Q. C. | Zheng, D. M. | Zheng, N. | Lv, X. G.
Mercury pollution in the Second Songhua River (SSR) was serious in the last century due to effluent from a chemical corporation. Effects of riverine self-purification on mercury removal were studied by comparing monitoring data of mercury concentrations varieties in water, sediment, and fish in the past, about 30 years. The present work suggested that a river of such a size like the SSR possessed the potential ability to recover from mercury pollution under the condition that mercury sources were cut off, though it needs a very long time, which might be several decades or even a century of years. During the 30 years with no effluent containing mercury input, total mercury (T-Hg) of water and sediment in some typical segments, mostly near the past effluent outlet, had decreased radically but still higher than the background values, though the decrease amplitudes were over 90% compared with that in 1975. T-Hg had decreased by more than 90% in most fishes, but some were still not suitable for consumption. Methylmercury concentrations (MeHg) of water, sediment, and fish were higher or close to the background levels in 2004. In the coming decades, the purification processes in the SSR would be steady and slow for a long period.
显示更多 [+] 显示较少 [-]Ecological Restoration of Polluted Plain Rivers Within the Haihe River Basin in China 全文
2010
Wang, W. | Tang, X. Q. | Huang, S. L. | Zhang, S. H. | Lin, C. | Liu, D. W. | Che, H. J. | Yang, Q. | Scholz, Miklas
The Haihe River basin is located in the north of China and has an area of 318,000 km². The region is politically important and economically advanced. For example, the Haihe River basin sustains a population of more than 120 million and generates a gross domestic production of approximately 2,600 billion Chinese Yuan. The ecological health of plain rivers within the Haihe River basin of China is questionable because of severe water shortages, considerable water, soil and air pollution, and the destruction of the natural river morphologies. It is therefore necessary to establish a generic and theoretical restoration methodology to guide river ecological restoration efforts in the future. Thirteen methodologies and technologies were selected from an existing suit of ecosystem restoration techniques currently applied to the Haihe River catchment. These technologies were further divided into three types: water quantity adjustment, water purification, and habitat improvement. The most suitable ecological restoration techniques were selected as a function of all three types. However, direct methods of addressing water quantity and quality problems were identified as critical for the success of future restoration efforts. Examples of the application of the conceptual ecological restoration model for the representative plain rivers Beiyunhe, Yongding and Wei, all located within the Haihe River Basin, are also assessed. The conceptual model provides practical solutions to pollution problems, is generic in nature, and could therefore be applied to other polluted watercourses in densely populated regions in the developed and developing world.
显示更多 [+] 显示较少 [-]Effects of Enhanced UV-B Radiation on N₂O Emission in a Soil-Winter Wheat System 全文
2010
Hu, Zhenghua | Jiang, Jingyan | Chen, Shutao | Liu, Qiaohui | Niu, Chuanpo
An outdoor pot experiments was conducted to investigate the effects of enhanced ultraviolet-B (UV-B) radiation on nitrous oxide (N₂O) emissions from soil-winter wheat systems. The enhanced UV-B radiation treatments were simulated by 20% increase in its intensity. N₂O fluxes were measured with a static opaque chamber-gas chromatograph method. The results showed that enhanced UV-B radiation did not change the seasonal patterns of N₂O emissions. Compared to the controls, the enhanced UV-B radiation reduced N₂O fluxes by 16.4% (p = 0.015) during the elongation-booting stage, while it had no significant effects on N₂O fluxes in the turning-green and heading-maturity phases. During the turning green-overall heading span, the accumulative N₂O was largely decreased by the enhanced UV-B radiation (p < 0.05). From the overall heading to maturity, however, the effects of enhanced UV-B on N₂O emissions were not pronounced (p > 0.10). At the elongation-booting stage, enhanced UV-B increased soluble proteins content in leaves, NO ₃ ⁻ -N and NO ₄ ⁺ -N content in rhizosphere soil, and soil microbial biomass C (C mic) and N (N mic; p < 0.05), as well as microbial biomass C:N ratio changing from 5.0 to 6.8. Our findings suggest that the effects of enhanced UV-B radiation on N₂O emissions differed with winter wheat developmental stages. To assess the overall effects of enhanced UV-B radiation on N₂O emissions from agroecosystems, nevertheless, more field measurements deserve to be carried out in various cropping systems.
显示更多 [+] 显示较少 [-]Atmospheric Deposition of Nitrogen and Sulfur in the Yellow Sea Region: Significance of Long-Range Transport in East Asia 全文
2010
Kim, J (Jin-Yong) | Ghim, Y. S. | Lee, S. B. | Moon, K. C. | Shim, S.-G. | Bae, G. N. | Yoon, S.-C.
The amounts of nitrogen and sulfur deposited in the region of the Yellow Sea in both dry and wet forms were estimated focusing on the period between 1999 and 2000. Dry deposition fluxes were obtained using concentrations from ground stations on both Korean and Chinese sides and from shipboard and aircraft measurements. Wet deposition fluxes were determined at ground stations on the Korean side. The dry deposition flux over the Yellow Sea was much greater than those for other world oceans. As a whole, the amounts of wet depositions of nitrogen and sulfur were 1.9 and 1.5 times larger than the amounts of respective dry depositions. Substantial influence from China caused by high emissions in East China and westerly wind was possibly suggested. However, the influence from nitrogen emission in Korea was also confirmed.
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