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排序方式: 共有4915条查询结果,搜索用时 15 毫秒
541.
Paula Paíga Kaline Amaral Wanderley Severino Alves Júnior C.M. Delerue-Matos 《毒物与环境化学》2015,97(6):687-699
Carbamate compounds are an important group of cholinesterase inhibitors. There is a need for creating awareness regarding the risks of the inadequate carbamate use in the residential areas due to potential adverse human effects. Carbaryl is a commonly used pesticide worldwide. A simple, fast, and high-throughput method was developed employing liquid chromatography with fluorescence detector to determine carbaryl residues in rat feces. The extraction was performed by using a rapid, easy, cheap, effective, reliable, and safe (QuEChERS) method, using acetonitrile as the extracting solvent. The parameters for the performance of the extraction method were optimized, such as ratio of mass of sample per volume of extraction solvent, QuEChERS content, and cleanup columns. Linear response was obtained for all calibration curves (solvent and matrix-matched) over the established concentration range (5–500 μg/L) with a correlation coefficients higher than 0.999. The achieved recovery was 97.9% with relative standard deviation values of 1.1% (n = 4) at 167 μg/kg fortified concentration level and the limits of detection and quantification were 27.7 and 92.3 µg/kg, respectively. 相似文献
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In situ soil water extraction: a review 总被引:4,自引:0,他引:4
Weihermüller L Siemens J Deurer M Knoblauch S Rupp H Göttlein A Pütz T 《Journal of environmental quality》2007,36(6):1735-1748
The knowledge of the composition and fluxes of vadose zone water is essential for a wide range of scientific and practical fields, including water-use management, pesticide registration, fate of xenobiotics, monitoring of disposal from mining and industries, nutrient management of agricultural and forest ecosystems, ecology, and environmental protection. Nowadays, water and solute flow can be monitored using either in situ methods or minimally invasive geophysical measurements. In situ information, however, is necessary to interpret most geophysical data sets and to determine the chemical composition of seepage water. Therefore, we present a comprehensive review of in situ soil water extraction methods to monitor solute concentration, solute transport, and to calculate mass balances in natural soils. We distinguished six different sampling devices: porous cups, porous plates, capillary wicks, pan lysimeters, resin boxes, and lysimeters. For each of the six sampling devices we discuss the basic principles, the advantages and disadvantages, and limits of data acquisition. We also give decision guidance for the selection of the appropriate sampling system. The choice of material is addressed in terms of potential contamination, filtering, and sorption of the target substances. The information provided in this review will support scientists and professionals in optimizing their experimental set-up for meeting their specific goals. 相似文献
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This report summarizes the results of two studies of electricity supply for Europe (EU), the Middle East (ME) and North Africa
(NA) up to the year 2050. It shows that a transition to competitive, secure and sustainable supply of electricity and water
is possible using renewable energy sources, efficiency gains and fossil fuel backup for balancing power. A strong cooperation
between the EU and MENA for the market introduction of renewable energy and the interconnection of the electricity grids by
high-voltage direct-current transmission are keys to the success and survival of the whole region. However, the necessary
measures will take at least two decades to become effective. Therefore, adequate policy and economic frameworks for their
realization must be introduced immediately. The importance of sustainable energy for the security of freshwater supplies in
MENA is also described.
相似文献
Hans Müller-SteinhagenEmail: |
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Roland Axt-Fliedner Andrii Kurkevych Maciej Slodki Maria Respondek-Liberska Katarzyna Zych-Krekora Rüdiger Stressig Jochen Ritgen Guiseppe Rizzo Martin Krapp Luc de Catte Gunther Mielke Stephan Bosselmann Mathias Meyer-Wittkopf Andreea Kawecki Aline Wolter Marios Mamalis Christian Enzensberger 《黑龙江环境通报》2017,37(8):812-819
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Diana Sietz Sabino Edgar Mamani Choque Matthias K. B. Lüdeke 《Regional Environmental Change》2012,12(3):489-505
Smallholder livelihoods in the Peruvian Altiplano are frequently threatened by weather extremes, including droughts, frosts and heavy rainfall. Given the persistence of significant undernourishment despite regional development efforts, we propose a cluster approach to evaluate smallholders’ vulnerability to weather extremes with regard to food security. We applied this approach to 268 smallholder households using information from two existing regional assessments and from our own household survey. The cluster analysis revealed four vulnerability patterns that depict typical combinations of household attributes, including their harvest failure risk, agricultural resources, education level and non-agricultural income. We validated the identified vulnerability patterns by demonstrating the correlation between them and an independently reported damage: the purchase of food and fodder resulting from exposure to weather extremes. The vulnerability patterns were then ranked according to the different amounts of purchase. A second validation aspect accounted for independently reported mechanisms explaining smallholders’ sensitivity and adaptive capacity. Based on the similarities among the households, our study contributes to the understanding of vulnerability beyond individual cases. In particular, the validation strengthens the credibility and suitability of our findings for decision-making pertaining to the reduction of vulnerability. 相似文献