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911.
van Wezel AP Morinière V Emke E ter Laak T Hogenboom AC 《Environment international》2011,37(6):1063-1067
The application of engineered nanomaterials increases strongly. Development of analytical techniques and their application to environmental samples is essential for human and environmental risk assessment of the nanoparticles. The objective of this study was to develop a sensitive analytical method to quantify nC(60) in water, using accurate mass screening liquid chromatography-hybrid linear ion trap Orbitrap mass spectrometry. nC(60) can be transformed by oxidation, reduction and photochemical reaction. Therefore, the formation of some transformation products of nC(60) was studied as well. Finally, the developed analytical method was applied to surface water samples from several locations in the Netherlands. The developed method enabled to detect and quantify aqueous concentrations of the summed nC(60) and its transformation products as low as 5 ng/L. It was observed that nC(60) transformation products exceed quantities of the parent C(60). Despite the high sensitivity of the developed method, no nC(60) or transformation products were detected in an array of Dutch surface waters. This might be due to low emissions, losses in the aqueous phase by sedimentation, sorption or further transformation processes. 相似文献
912.
de Nazelle A Nieuwenhuijsen MJ Antó JM Brauer M Briggs D Braun-Fahrlander C Cavill N Cooper AR Desqueyroux H Fruin S Hoek G Panis LI Janssen N Jerrett M Joffe M Andersen ZJ van Kempen E Kingham S Kubesch N Leyden KM Marshall JD Matamala J Mellios G Mendez M Nassif H Ogilvie D Peiró R Pérez K Rabl A Ragettli M Rodríguez D Rojas D Ruiz P Sallis JF Terwoert J Toussaint JF Tuomisto J Zuurbier M Lebret E 《Environment international》2011,37(4):766-777
913.
Baeza A Vallejo I Guillén J Salas A Corbacho JA 《Journal of environmental radioactivity》2011,102(3):311-315
Adequate radioprotection of the environment requires the identification of biomonitors sensitive to the variation of its radionuclide content. Due to the chemical similarities between calcium and strontium, calcified tissues of mammals are considered to be good 90Sr biomonitors. This work considered Cervus elaphus antlers which, being shed annually, can give information about the importance of radiostrontium contamination in an ecosystem in the time period required for the growth of the antler. The samples were collected at various points of W and SW Spain. The mean value of their 90Sr content was (70 ± 43 (S.D.)) Bq/kg d.w., range (16-218) Bq/kg d.w., and the radionuclide was evenly distributed in the different parts of the antler. There was a good correlation between the antlers’ 90Sr content and the 90Sr deposited in the soil. The antlers’ content of 226Ra (from the natural uranium series) and the contents of some stable elements (Ca, Mg, Sr, and K) were also determined. The values for these stable elements were practically constant in the analyzed samples, and the concentrations measured decreased in the following order:Ca » Mg > K > Sr » 90Sr > 226Ra 相似文献
914.
Jiménez MA Martín-Valdepeñas JM García-Talavera M Martín-Matarranz JL Salas MR Serrano JI Ramos LM 《Journal of environmental radioactivity》2011,102(11):995-1007
In the frame of an epidemiological study carried out in the influence areas around the Spanish nuclear facilities (ISCIII-CSN, 2009. Epidemiological Study of The Possible Effect of Ionizing Radiations Deriving from The Operation of Spanish Nuclear Fuel Cycle Facilities on The Health of The Population Living in Their Vicinity. Final report December 2009. Ministerio de Ciencia e Innovación, Instituto de Salud Carlos III, Consejo de Seguridad Nuclear. Madrid. Available from: http://www.csn.es/images/stories/actualidad_datos/especiales/epidemiologico/epidemiological_study.pdf), annual effective doses to public have been assessed by the Spanish Nuclear Safety Council (CSN) for over 45 years using a retrospective realistic-dose methodology. These values are compared with data from natural radiation exposure. For the affected population, natural radiation effective doses are in average 2300 times higher than effective doses due to the operation of nuclear installations (nuclear power stations and fuel cycle facilities). When considering the impact on the whole Spanish population, effective doses attributable to nuclear facilities represent in average 3.5 × 10−5 mSv/y, in contrast to 1.6 mSv/y from natural radiation or 1.3 mSv/y from medical exposures. 相似文献
915.
Silvana Kuhtz 《Environment, Development and Sustainability》2011,13(1):79-85
Climate is one of the more complex physical systems in nature, its behaviour being fundamentally non-linear and chaotic. In
assessing the potential risks from climate change and the costs of averting it, researchers and policymakers encounter pervasive
uncertainty. Sceptics demand to get rid of the inherent uncertainties, and some experts, on the other end, keep sending out
messages of catastrophic scenarios hoping that this will increase people’s awareness of the danger we face. The recent admission
of a mistake in IPCC’s Climate change 2007 report (promptly broadcast by all the major media groups and newspapers from Jan. 20th 2010 onwards) made by the head of
the Intergovernmental Panel on Climate Change—that Himalayan glaciers could melt away by 2035 (the IPCC claim of 2035 is wrong
by over 300 years.)—has already brought a damage to the IPCC’s reputation that is likely to be considerable. But in this paper,
perhaps risking being provocative and paradoxical, instead of looking for the right answers to what we think are inevitable uncertainties, we intend to search for new questions that may lead to a new way of
thinking and may bring about new lifestyles and behaviour for citizens and firms. 相似文献
916.
Thaddeus Chidi Nzeadibe Chukwuedozie K. Ajaero 《Environment, Development and Sustainability》2011,13(1):163-177
Solid waste management (SWM) in many low- and middle-income countries is sometimes driven by the informal sector. Unfortunately,
contributions of the sector to SWM are not acknowledged in many developing countries. This situation often arises from inadequate
awareness and lack of advocacy for these development contributions. This article reports on the impact of a study conducted
by final-year geography undergraduates on the informal waste management sector in Nsukka urban area, Nigeria. The purposes
of this exercise were to stimulate development intervention on behalf of the sector to improve perceptions, attitudes and
performance, to impart a range of development research skills and to expose the students to the business opportunities provided
by SWM and recycling. Informal waste sector workers and government officials responsible for SWM were interviewed, and some
commercial data on recycling operations were collected. Findings of this study indicate that such advocacy initiatives were
effective in increasing students’ awareness of opportunities and interest in working in the informal waste sector to promote
better SWM and development in Nigeria. Lessons from this university case study are also drawn for other developing countries
struggling to achieve the poverty reduction and job creation Millennium Development Goals (MDGs). 相似文献
917.
Julius H. Kotir 《Environment, Development and Sustainability》2011,13(3):587-605
Sub-Saharan Africa has been portrayed as the most vulnerable region to the impacts of global climate change because of its
reliance on agriculture which is highly sensitive to weather and climate variables such as temperature, precipitation, and
light and extreme events and low capacity for adaptation. This article reviews evidence on the scope and nature of the climate
change challenge; and assesses the impact of climate change on agriculture and food security in Sub-Saharan Africa. From the
review, it is apparent that the climate in Africa is already exhibiting significant changes, evident by changes in average
temperature, change in amount of rainfall and patterns and the prevalence of frequency and intensity of weather extremes.
The review also revealed that although uncertainties exist with regards to the magnitude of impacts, climate will negatively
affect agricultural production in Sub-Saharan Africa. Specifically, as result of current and expected climate change, the
area suitable for agriculture, the length of growing seasons and yield potential, particularly along the margins of semi-arid
and arid areas, are expected to decrease. These impacts will affect all components of food security: food availability, food accessibility, food utilisation and food stability and hence increase the risk of hunger in the region. The review thus confirms the general consensus that Sub-Saharan Africa
is the most vulnerable region to climate change. It suggests that, policymakers and development agencies should focus on formulating
and implementing policies and programmes that promote farm level adaptation strategies currently being practiced by farmers
across the region. 相似文献
918.
Colin Thor West 《Environment, Development and Sustainability》2011,13(1):217-235
The Arctic is a region of the world experiencing extremely rapid climatic and social change. Indigenous communities have faced
similar challenges for millennia and have historically demonstrated remarkable resilience to socioecological perturbations.
In contemporary contexts, however, it appears that the pace and extent of change is overwhelming the adaptive capacities of
many indigenous communities. Scholars recently completed a survey of living conditions spanning the circumpolar Arctic to
quantitatively document the impacts of social and ecological stress across regions. The database they created is called the
Survey of Living Conditions in the Arctic or SLiCA. This article explores the utility of using this dataset to compare livelihood
systems across three sub-regions of Alaska and four sub-regions within the Chukotka Autonomous Okrug of the Russian Federation.
The results point out that livelihood systems in Chukotka have a substantially lower level of sustainability than in Northwest
Alaska due to the high prevalence of vulnerable households. 相似文献
919.
Masahiko Matsuda 《Environment, Development and Sustainability》2011,13(1):51-64
This study aims to estimate the intensification of rice farming in Myanmar particularly due to chemical fertilizer application,
using farm-level data obtained from field surveys conducted in the 2000s. Relatively high-input rice farming was found in
dry season crop in the delta zone and the double crop in well-irrigated lowlands of the central dry zone. The chemical fertilizer
used there was about 88–159 kg NPK (nitrogen, N; phosphate, P2O5; and potash, K2O) ha−1 (76–110 kg nitrogen (N) ha−1), and the average paddy yield ranged from 2.8 to 3.5 ton ha−1. On the other hand, nutrient input in survey sites of rain-fed lowland was between 11 and 53 kg NPK ha−1 (5 and 36 kg N ha−1), and the yield ranged from 1.1 to 2.3 ton ha−1. The national average of paddy yield and nutrient input of fertilizer was roughly estimated to be around 2.4 ton ha−1 and 60 kg NPK ha−1, respectively. A gap was observed between these calculated values and the official statistics. A comparison of fertilizer
use efficiency for rice production in Myanmar with that in China and Vietnam has shown that the efficiency in Myanmar has
not declined to an inappropriate level even in its intensive ones. Rice production in Myanmar has room for increasing the
yield by capital intensification. Nevertheless, considering its sustainability as well as productivity, further intensification
in rice farming technology in irrigated lowlands of Myanmar may neither be the best nor the only way. 相似文献
920.
Renewable energy sources are mainly used in the electrical sector. Electricity is not a storable commodity. Hence, it is necessary
to produce the requested quantity and distribute it through the system in such a way as to ensure that electricity supply
and demand are always evenly balanced. This constraint is actually the main problem related to the penetration of new renewables (wind and photovoltaic power)
in the context of complex energy systems. The paper analyzes some aspects in connection with the problem of new renewable
energy penetration. The case of Italian scenario is considered as a meaningful reference due to the characteristic size and
the complexity of the same. The various energy scenarios are evaluated with the aid of a multipurpose software taking into
account the interconnections between the different energetic uses. In particular, it is shown how the penetration of new renewable
energies is limited at an upper level by technological considerations and it will be more sustainable if an integration of
the various energy use (thermal, mobility and electrical) field will be considered. 相似文献