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81.
This paper is focused on novel utilizations of the fundamental modes of deformation of tube end forming for assembling sheet panels to thin-walled tubular profiles.The objective is to present an innovative and environmental friendly joining technology built upon the combination of compression beading with tube inversion that can successfully eliminate currently available technologies based on mechanical fixing with fasteners, welding and structural adhesive bonding. The technology works at room temperature, is capable of ensuring significant economic and time savings and offers potential for opening new markets for the assembly of lightweight frame structures.The presentation is supported by experimentation and numerical modelling based on independently determined mechanical properties of the materials with the purpose of characterizing and evaluating the process feasibility limits as a function of the major operative parameters.The feasibility of joining sheet panels to tubular profiles by means of the proposed technology is demonstrated by presenting industrial applications and by evaluating the performance of a safety auto part in an operation failure test.  相似文献   
82.
83.
Heavy metal contamination of the environment is a public health problem and research to develop new tools for monitoring the environmental impact of these elements is necessary. This study describes the preparation of a rhodamine-based probe 1 and its potential applications for detecting mercuric ion [Hg(II)] in samples from a nutrition media containing Salvinia auriculata. It was observed that an excess of probe 1 led to quenching in the fluorescence/absorption response, which was evidenced by a decrease in the signal when the stoichiometry differed from 1:1. Consequently, this probe is not suitable for quantitative analysis of Hg(II). Also, probe 1 reacts with methylmercury (MeHg) with different stoichiometry than that observed for Hg(II). These results indicate the potential application of probe 1 for qualitative detection of Hg(II) and MeHg in environmental samples.  相似文献   
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85.
International retirement migration has become an increasing phenomenon in the Mediterranean region of Alicante, Spain. Through an interdisciplinary approach, relationships between the migration process, landscape change and environmental impacts are examined. Lifestyle-related perceptions and demands of UK retirees are studied as a major driving force of urbanisation. The extent and quality of the process is assessed by statistical and land use data analysis. Results reveal a distinctive spatial pattern of in-migration and the emergence of an archetypical landscape, consisting of a mosaic of remaining natural and urbanised landscape along the Mediterranean coast. The paper discusses the necessity of retirees' integration into sustainable planning and decision making.  相似文献   
86.
The Brazilian program of payment for environmental services (PES) is based on ranges of potential erosion decrease (ED) from soil and water conservation proposals estimated from the Universal Soil Loss Equation. Changes in land use and land cover (LULC) result in many alterations of the basin water balance. Therefore, to contribute to the methodological development of Brazilian PES, this paper proposes a quantification of hydrological benefits based on conservation measures. We propose basing the PES program on adding the potential water storage increase (WSI) parameter estimated from the runoff curve number model. Two LULC change scenarios were run considering conservation measures on degraded areas. We found that indicators of ED and WSI were compatible tools for driving the eligibility of soil and water conservation measures. However, the water storage parameter seems to be better at managing the PES mechanism because it is based on water prices and can contribute to appreciation of the efforts performed by the rural producers. The use of the SCS-CN method presents greater feasibility as a tool for the implementation of PES programs in ungauged basins. Thus, an analysis of the success of the innovation proposal of the Brazilian PES program allows inferences to be made about the quantification and financial valuation of hydrological benefits of the potential storage increase and current water price.  相似文献   
87.
Journal of Material Cycles and Waste Management - The massive generation of municipal solid waste (MSW) has become an essential social problem that not only damages the ecological environment but...  相似文献   
88.
Environmental Science and Pollution Research - Free-living birds play an important role as bioindicators in natural environments. In this study, we used the micronucleus test and nuclear...  相似文献   
89.
Environmental Science and Pollution Research - A new one-pot synthesis method optimized by a 23 experimental design was developed to prepare a biosorbent, sugarcane bagasse cellulose succinate...  相似文献   
90.
Alves C  Pio C  Carvalho A  Santos C 《Chemosphere》2006,63(1):153-164
A labour-intensive analytical technique was applied to atmospheric particulate matter samples collected in a German urban/industrial influenced grassland location (Melpitz) and in a Finnish forest area (Hyyti?l?) in order to achieve a detailed chemical speciation of the organic content. The representative nature of the solvent and water-extractable fractions was determined. The organic compounds identified in the solvent extracts are represented by primary compounds with both anthropogenic and biogenic origin, which mainly derive from the vegetation waxes and from petrogenic sources. Secondary products resulting from the oxidation of volatile organic compounds were also detected. The German meadow presented the highest levels of sugars and acidic compounds in the water extracts, whilst polyols were the most abundant class in the Finnish forest. The major compounds of these classes were malic acid, mannitol, arabitol, glucose and sucrose. Levoglucosan was also found in the water extract.  相似文献   
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