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991.
Climate adaptation is a complex task surrounded by uncertainty. To support climate adaptation policies, a new scenario approach is pursued to explore possible discontinuous future developments of societal perspectives on climate adaptation issues. The scenario approach was tested for a case study on Dutch river management. In a series of scenario development workshops, a select group of stakeholders explored the perspectives on the management of the River Meuse in the past, present, and future. The process was supported by an analytical perspectives mapping tool to illustrate and analyze the development of perspectives over time. The process and analytical tools contributed to insight into the drivers of perspective change for the case study at hand. Moreover, the stakeholders highlighted the potential of the approach for water management policy for creating awareness about the plurality of perspectives and the dynamics of perspective change, monitoring perspectives and perspective change as part of a flexible policy approach, and anticipating on the occurrence of shock events. Further work is required to better represent the social dynamics of perspectives change, to better empirically ground the perspective change model, and to apply integrated water models in the scenario development process to assess water–society interactions.  相似文献   
992.
Renewable energy is considered an indispensable basis of sustainable energy systems as electricity generation from renewable sources results in low emissions of greenhouse gases compared to fossil fuel based electricity and contributes to sustainable development. However, effective strategies and conducive institutional settings are needed for advancement of such clean electricity systems. Although Thailand, as a nation, has a huge potential for renewable energy utilization, its total amount of electricity generation from renewables is relatively small and could be enlarged substantially. Lack of policy mechanisms, institutional development and financing exist as major barriers for Thailand in this regard. Investigation of the nation’s current energy strategy implementation shows that relevant energy and development policies are at different stages of implementation and institutional settings are continuously evolving. This paper argues that further significant efforts could be made towards advancement of renewable electricity and thus achievement of energy sustainability in Thailand. Resource planning, effective policy and institutions, focussed planning for energy sustainability and implementation of the Clean Development Mechanism (CDM) under the Kyoto Protocol could facilitate further advancement of renewables for the nation.  相似文献   
993.
Starch nanocomposites have been prepared using mineral clay. Montmorillonite, kaolin and a surface-modified montmorillonite by dimethyl (hydrogenated tallow alkyl) ammonium cation were used. Starch-g-PCL nanocomposites have been prepared with graft polymerization through in situ ring-opening polymerization of ε-caprolactone in the presence of starch, Sn(Oct)2 (Tin(II) 2-ethyl hexanoate) as an initiator/catalyst and silicate layers. In fact, the related composites were prepared in solution method, bulk polymerization and in situ polymerization methods with introducing the mineral clay. The effect of kind of clay on d-spacing of silicate layers was investigated and the obtained nanocomposites were analyzed using X-ray diffraction. The obtained compounds were characterized by Fourier transform infrared (FT-IR). Morphology of the prepared nanocomposites was investigated using scanning electron microscopy and DSC enhanced the study of thermal behaviour of the prepared composite compounds.  相似文献   
994.
Effective handling of municipal digested sludge requires that the product cake have low water content. To this end, we investigated the change in sludge dewaterability after the addition of fly ash to municipal digested sludge, dewatering of which is difficult because of its high organic content. The performance of the dewatering is compared with that of electroosmotic dewatering (EDW) and conventional mechanical dewatering (CMD). Fly ash classified by sieving to the size of 25–75 μm and >75 μm is added to the municipal digested sludge by 10, 20, and 50 wt% by wet base. When adding fly ash particles to municipal digested sludge, dewatering efficiency improved with smaller fly ash particle size and with increase in the amount. When sludge was dewatered using an electroosmotic dewatering method, the dewatering efficiency is improved about 40% by adding fly ash of 25–75 μm particle size with 20 wt% when compared with conventional mechanical dewatering method without adding the fly ash. It is concluded that fly ash particles rich in inorganic material are helpful in the dewatering process when added to municipal digested sludge and EDW is more effective than CDW.  相似文献   
995.
The biodegradability, morphology, and mechanical properties of composite materials made of Poly(butylene adipate-co-terephthalate) (PBAT) and sisal fiber (SF) were evaluated. Composites containing acrylic acid-grafted PBAT (PBAT-g-AA/SF) exhibited noticeably superior mechanical properties due to greater compatibility between the two components. The dispersion of SF in the PBAT-g-AA matrix was highly homogeneous as a result of ester formation between the carboxyl groups of PBAT-g-AA and hydroxyl groups in SF and the consequent creation of branched and cross-linked macromolecules. Each composite was subjected to biodegradation tests in Rhizopus oryzae compost. Morphological observations indicated severe disruption of film structure after 60 days of incubation, and both the PBAT and the PBAT-g-AA/SF composite films were eventually completely degraded. Water resistance of PBAT-g-AA/SF was higher than that of PBAT/SF, although weight loss of composites buried in Rhizopus oryzae compost indicated that both were biodegradable, even at high levels of SF substitution. The PBAT-g-AA/SF films were more biodegradable than those made of PBAT, implying a strong connection between these characteristics and biodegradability.  相似文献   
996.
Regional landscape ecological security is an important issue for ecological security, and has a great influence on national security and social sustainable development. The Pearl River Delta (PRD) in southern China has experienced rapid economic development and intensive human activities in recent years. This study, based on landscape analysis, provides a method to discover the alteration of character among different landscape types and to understand the landscape ecological security status. Based on remotely sensed products of the Landsat 5 TM images in 1990 and the Landsat 7 ETM+ images in 2005, landscape classification maps of nine cities in the PRD were compiled by implementing Remote Sensing and Geographic Information System technology. Several indices, including aggregation, crush index, landscape shape index, Shannon’s diversity index, landscape fragile index, and landscape security adjacent index, were applied to analyze spatial–temporal characteristics of landscape patterns in the PRD. A landscape ecological security index based on these outcomes was calculated by projection pursuit using genetic algorithm. The landscape ecological security of nine cities in the PRD was thus evaluated. The main results of this research are listed as follows: (1) from 1990 to 2005, the aggregation index, crush index, landscape shape index, and Shannon’s diversity index of nine cities changed little in the PRD, while the landscape fragile index and landscape security adjacent index changed obviously. The landscape fragile index of nine cities showed a decreasing trend; however, the landscape security adjacent index has been increasing; (2) from 1990 to 2005, landscape ecology of the cities of Zhuhai and Huizhou maintained a good security situation. However, there was a relatively low value of ecological security in the cities of Dongguan and Foshan. Except for Foshan and Guangzhou, whose landscape ecological security situation were slightly improved, the cities had reduced values in landscape ecological security, with the most decreased number 0.52 in Zhaoqing. Results of this study offer important information for regional eco-construction and natural resource exploitation.  相似文献   
997.
This study investigated the presence of total mercury (Hg) and organic mercury levels in the muscle of 19 common fresh water fish species captured from river Ganges, West Bengal, India. The total mercury level found in our study may not cause any toxic effect, but the methyl mercury (MeHg) level in some freshwater fish species was surprisingly very high and toxically unacceptable. The results of mercury analysis in various specimens indicated that some fish muscles tended to accumulate high levels of Hg, and approximately 50–84% of Hg was organic mercury. A strong positive correlation between mercury levels in muscle with food habit and fish length (age) was found. Wallago attu possessed the highest amount of organic mercury in their muscle tissues, and it was 0.93 ± 0.61 μg Hg/g of wet weight. Whereas in small-sized fishes Eutropiichthys murius, Puntius sarana, Cirrhinus mrigala, Mystus vittatus or Mystus gulio, and Tilapia mossambicus, it was below the detection limit. Contamination in Catla catla (0.32 ± 0.11), Anguilla bengalensis bengalensis (0.26 ± 0.07 μg Hg/g), Chitala chitala (0.25 ± 0.18), Rita rita (0.34 ± 0.14), and Ompok pabda (0.26 ± 0.04) was also above the 0.25 μg Hg/g of wet weight, the limit set by the PFA for the maximum level for consumption of fish exposed to MeHg. Though in Labeo rohita (0.12 ± 0.03), Mastacembelus armatus (0.17 ± 0.02), Pangasius pangasius (0.12 ± 0.16), Bagarius bagarius (0.12 ± 0.01), and Clupisoma garua (0.1 ± 0.01), concentration was below the recommended level, in Lates calcarifer (0.23 ± 0.0) and Mystus aor (0.23 ± 0.1), it was threatening. Interestingly, a low concentration of Hg was found in post-monsoon samples.  相似文献   
998.
When agricultural lands are no longer used for agriculture and allowed to recover its natural vegetation, soil organic carbon can accumulate in the soil. Measurements of soil organic carbon and aggregate stability changes under various forms of land use are needed for the development of sustainable systems. Therefore, comparison of soil samples taken from both agricultural and nearby area close to land-mined fields where no agricultural practices have been done since 1956 can be a good approach to evaluate the effects of tillage and agriculture on soil quality. The objective of this study was to compare tillage, cropping and no tillage effects on some soil-quality parameters. Four different locations along the Turkey–Syria border were selected to determine effects of tillage and cropping on soil quality. Each location was evaluated separately because of different soil type and treatments. Comparisons were made between non-tilled and non-cropped fallow since 1956 and adjacent restricted lands that were tilled about every 2 years but not planted (T) or adjacent lands tilled and planted with wheat and lentil (P). Three samples were taken from the depths of 0–20 and 20–40 cm each site. Soil organic carbon (SOC), pH ,electrical conductivity, water soluble Ca++, Mg++, CO3-2{\rm CO}_{3}^{-2} and HCO3-{\rm HCO}_{3}^{-}, extractable potassium (K+) and sodium (Na+), soil texture, ammonium (NH4+{\rm NH}_{4}^{+}–N) and nitrate (NO3–N), extractable phosphorous and soil aggregate stability were determined. While the SOC contents of continuous tillage without cropping and continuous tillage and cropping were 2.2 and 11.6 g kg−1, respectively, it was 30 g kg−1 in non-tilled and non-planted site. Tillage of soil without the input of any plant material resulted in loss of carbon from the soil in all sites. Soil extractable NO3−N contents of non-tilled and non-cropped sites were greatest among all treatments. Agricultural practices increased phosphorus and potassium contents in the soil profile. P2O5 contents of planted soils were approximately 20 to 39 times greater than those of non-tilled and non-cropped soils at different sites. FTIR spectra showed that never tilled sites had greater phenol, carboxylic acid, amide, aromatic compounds, polysaccharide and carbohydrates than other treatments.  相似文献   
999.
Awareness of farm animal welfare issues is growing in Canada, as part of a larger food movement. The baseline Canadian standards for farm animal welfare—the Recommended Codes of Practice for the Care and Handling of Farm Animals—are up for revision. The success of these standards will depend in part on perceived legitimacy, which helps determine whether voluntary code systems are adopted, implemented, and accepted by target audiences. In the context of the Codes, legitimacy will also hinge on whether the standards-developers marshal narratives about farm animals that accord with their audiences’ expectations. The aim of this paper is to catalogue factors that influence legitimacy in farm animal welfare standard-setting, including which narratives of animal welfare are emphasized by standard-setters. Drawing upon the example of the baseline Canadian standards, and the National Farm Animal Care Council, the paper will present a theoretical and methodological framework for analyzing legitimacy in the context of animal welfare standards-development and discuss associated policy considerations.  相似文献   
1000.
Blends of water—soluble polymers based on Poly vinyl alcohol (PVA) and Polyethylene glycol (PEG) have been prepared by the solution casting technique. The effect of various doses of γ-radiation on the structural properties of PVA/PEG polymer blends with all its compositions has been investigated. From the visual observation of all the blend compositions, it was found that, the best compatibility of the blend is up to 40% PVA/60%PEG. The structure–Property behavior of all the prepared blends before and after γ-irradiation was investigated by IR Spectroscopy, thermogravimetric analysis (TGA), mechanical properties and Scanning electron microscope (SEM). The gel content and the swelling behavior of the PVA/PEG blends were investigated. It was found that the gel content increases with increasing irradiation dose and PVA concentration in the blend. Swelling percent increased as the composition of PEG increased in the blend. The results obtained by FTIR analysis and SEM confirm the existence of possible interaction between PVA and PEG homopolymers. TGA of PVA/PEG blend, before and after γ-irradiation, showed that the unirradiated and irradiated PVA/PEG blends are more stable against thermal decomposition than pure PVA. Improvement in tensile mechanical properties of PVA/PEG blends was occurred.  相似文献   
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