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131.
Among the difficulties found in the implementation of ISO 14001 systems, resistance to change can always be found. It is mainly a consequence of the hurry to change, loss of focus, concentration of decision making at the level of top management, arbitrary imposition of objectives and results, faulty communication, and the absence of motivational and financial incentive for change.Therefore, the main objective of this paper is to present best practices with respect to the management of organizational change due to the implementation of ISO 14001 norms in two industrial companies in the Midwest region of the State of São Paulo – Brazil.  相似文献   
132.
We studied issues of organophosphorus agents’ analysis. Immobilised enzyme–inhibitors complexes (e.g. acetylcholinesterase-organophosphate nerve agent) were studied with modified Ellman’s biochemical method utilised for assessment of acetylcholinesterase activity. Biochemical reactions are widespread and they are the most frequent used analytical methods for determination of nerve agents. This modified method is based on the nucleophilic reactions of mono- and bispyridinium aldoximes of a type 2-PAM, MMB-4 and HI-6, their homologues and isomers with enzyme–inhibitor complexes. The procedure for a gradual analysis of G and V type, Sarin, Cyclohexylsarin, Soman, Tabun, agent VX and R-33 was proposed in terms of studied nucleophilic substitution reactions quantification results. This method enables selective determination of these chemical warfare agents. A gradual analysis was evaluated by statistic method of probabilistic calculus. This type of analysis can be used for assessment of acetylcholinesterase inhibitors in very low concentrations close to hygienic limits.  相似文献   
133.
Potentiometric mass titration (PMT) technique has been adapted to determine the pH pzc of four vegetable wastes: grape stalks, cork, yohimbe bark and olive stones wastes used for Cu(II) removal. The pH at the point zero charge (pH pzc), determined by PMT, are compared with that obtained by two classical techniques: mass titration (MT) and immersion technique (IT). PMT has been found to be an easy and appropriate technique to determine pH pzc of the studied materials. From the results, the knowledge of sorbents pH pzc provides information about the possible attraction and repulsion between sorbent and sorbate but in any case enables to ensure that electrostatic force is one of the mechanisms that takes place in metal sorption.  相似文献   
134.
Rainfall trends in twentieth century over Kerala,India   总被引:1,自引:0,他引:1  
Attempts were made to study temporal variation in monthly, seasonal and annual rainfall over Kerala, India, during the period from 1871 to 2005. Longterm changes in rainfall determined by Man-Kendall rank statistics and linear trend. The analysis revealed significant decrease in southwest monsoon rainfall while increase in post-monsoon season over the State of Kerala which is popularly known as the “Gateway of summer monsoon”. Rainfall during winter and summer seasons showed insignificant increasing trend. Rainfall during June and July showed significant decreasing trend while increasing trend in January, February and April. Hydel power generation and water availability during summer months are the concern in the State due to rainfall decline in June and July, which are the rainiest months. At the same time, majority of plantation crops are likely to benefit due to increase in rainfall during the post-monsoon season if they are stable and prolonged.  相似文献   
135.
As part of the tier 2 of a site-specific risk assessment, this study was the first reporting an intensive in situ application of the bait-lamina assay; two exposure periods (7 and 14 days) were tested during four seasons in ten different sites, within a uranium mine area and at two different depths. The most contaminated sites (by deposition of sludge from the effluent treatment pond) were discriminated after 14 days of exposure because extremely low percentages of feeding activity were recorded. Previous sub-lethal ecotoxicological assays, already had demonstrated that the habitat function of these soils is compromised. Nevertheless, seasonality has proved to have a significant influence on responses. Thus to strength conclusions about the impact of contaminants, the in situ bait-lamina assay should be performed on different annual seasons, at least for temperate regions. It was also found that some environmental parameters (e.g. soil moisture and litter) can act as confounding factors in the bait-lamina assay.  相似文献   
136.
One-year quantitative chemical data set consisting of water-soluble constituents (NH4+, Na+, K+, Mg2+, Ca2+, Cl?, NO3?, SO42? and HCO3?), crustal and trace elements (Al, Fe, Ca, Mg, K, Mn, Zn, Pb) and carbonaceous species (OC, EC) in ambient aerosols, collected over an urban site located in a high-dust semi-arid region of western India, reveals excellent linear relationship (r2 = 0.92; slope = 0.96 ± 0.05) between gravimetrically assessed TSP (total suspended particulates) and chemically analyzed aerosol mass. The TSP abundance ranging from 60 to 250 μg m?3, over a period of 12 months (January–December), is dominated by mineral dust (~70%); whereas contribution from sea-salts, anthropogenic and carbonaceous species exhibits significant temporal variability depending upon the wind regimes. The mineral dust is enriched in Ca, Mg and Fe with respect to upper continental crust (UCC); whereas Zn and Pb exhibit a characteristic anthropogenic source and high enrichment factors. The carbonaceous species show significant seasonality; with dominance of OC (range: 4.6–28 μg m?3; average: 12.8 μg m?3; SD: 6.8) and minor contribution from EC (range: 0.3–4.4 μg m?3; average: 2.4 μg m?3; SD: 1.4). The observed concentrations are significantly lower than those reported for the metro cities in South Asia but the OC/EC ratios (range: 4.3–35; average: 8.3; SD: 5.7) are significantly higher than the characteristic ratio (~2–4) reported for the urban atmosphere. Such quantitative chemical characterization of aerosols is essential in assessing their role in atmospheric chemistry and climate change. This study could also be useful in understanding the physical and optical aerosol properties documented from the same site and thus, in validating regional climate models.  相似文献   
137.
在政策支持和实际需求的驱动下,可能会导致县级地区垃圾焚烧项目迅速增多,且带来潜在的环境监管压力和环境社会风险,需要给予持续的特别关注,并对地方做好环境监管和风险管控的指导。本文基于全国精细化的生活垃圾焚烧处理设施、生活垃圾产生量、网络舆情等数据,通过构建泰森多边形等空间分析方法进行了焚烧处理设施的服务范围识别及负荷率计算,通过自然语言处理技术进行了关于生活垃圾焚烧处理设施的情感分析。在此基础上,基于焚烧处理设施的负荷率和负面舆情比例,对31个省份环境社会风险进行定量的评估分析并提出对策建议,一是平衡解决“缺口大”和“吃不饱”问题,合理规划布局县级地区生活垃圾焚烧处理设施;二是聚焦负面舆情高发领域、区域,积极防范县级地区生活垃圾焚烧处理设施环境社会风险。  相似文献   
138.
139.
Local, regional, and global extinctions caused by habitat loss, degradation, and fragmentation have been widely reported for the tropics. The patterns and drivers of this loss of species are now increasingly well known in Amazonia, but there remains a significant gap in understanding of long‐term trends in species persistence and extinction in anthropogenic landscapes. Such a historical perspective is critical for understanding the status and trends of extant biodiversity as well as for identifying priorities to halt further losses. Using extensive historical data sets of specimen records and results of contemporary surveys, we searched for evidence of local extinctions of a terra firma rainforest avifauna over 200 years in a 2500 km2 eastern Amazonian region around the Brazilian city of Belém. This region has the longest history of ornithological fieldwork in the entire Amazon basin and lies in the highly threatened Belém Centre of Endemism. We also compared our historically inferred extinction events with extensive data on species occurrences in a sample of catchments in a nearby municipality (Paragominas) that encompass a gradient of past forest loss. We found evidence for the possible extinction of 47 species (14% of the regional species pool) that were unreported from 1980 to 2013 (80% last recorded between 1900 and 1980). Seventeen species appear on the International Union for Conservation of Nature Red List, and many of these are large‐bodied. The species lost from the region immediately around Belém are similar to those which are currently restricted to well‐forested catchments in Paragominas. Although we anticipate the future rediscovery or recolonization of some species inferred to be extinct by our calculations, we also expect that there are likely to be additional local extinctions, not reported here, given the ongoing loss and degradation of remaining areas of native vegetation across eastern Amazonia. Doscientos Años de Extinciones Locales de Aves en la Amazonia Oriental  相似文献   
140.
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