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The regional imbalance in the Malaysian economy has long been recognised and continues to be a problem for development planning. The federal government has attempted to promote banking in the less developed regions in order to generate economic growth. Bank branches in Malaysia have increased in number and have also become regionally more dispersed. However, the regional concentration of bank branches is strongly associated with individual incomes. Hence, the growth of banking in Malaysia appears to be demand‐following rather than supply‐leading. Nevertheless, the intentional promotion of banking is continuing and beginning to produce some encouraging results. 相似文献
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Sedimentary geochemical record of historical anthropogenic activities affecting Guanabara Bay (Brazil) environmental quality 总被引:3,自引:2,他引:1
Fábio F. Monteiro Renato C. Cordeiro Ricardo E. Santelli Wilson Machado Heitor Evangelista Leonardo S. Villar Luis C. A. Viana Edison D. Bidone 《Environmental Earth Sciences》2012,65(6):1661-1669
A sediment core from Guanabara Bay (Brazil) was analyzed for 210Pb dating, grain size, total organic carbon (TOC) and total nitrogen, carbon stable isotope ratio (δ13C), nitrogen stable isotope ratio (δ15N) and the metals Fe, Mn, Ni, Co, Cu, Pb, V and Zn, to assess the influence of land use changes on the aquatic system in a
region for which large industrial and urban development is expected in the next few decades. To obtain baseline data for improving
the monitoring of the expected increase in anthropogenic impacts from surrounding drainage basins, a multivariate analysis
of data from different sediment layers was carried out to evaluate the dated sediment record. The geochemical data suggested
three different sedimentary phases along the last 200 years. Before the 1880s, the highest clay and TOC contents were observed,
where the C/N ratios and the δ13C values suggested a mixture of algal and terrestrial organic matter and the lowest concentrations of Co, Cu, Pb, V and Zn,
for which background levels were estimated (4.6, 2.7, 14.9, 24.3 and 70.2 mg kg−1, respectively). From the 1880s to the 1950s, the metal concentrations and sand particles increased, but no change in organic
matter quality was observed, reflecting a period of land use change, still without significant sewage input. After the 1950s,
the sedimentation rate increased from 0.42 to 0.77 cm year−1 and increasing urban sewage input was evidenced by lower C/N ratios, higher δ15N, decrease of Fe and Mn concentrations and increased fluxes of metals and TOC, which showed a good relationship with population
growth data. 相似文献
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Ricardo Cesar Marianna Silva Juan Colonese Edison Bidone Silvia Egler Zuleica Castilhos Helena Polivanov 《Environmental Earth Sciences》2012,66(8):2281-2292
The toxicity and potential bioavailability of heavy metals were studied in sewage sludge-amended ferralsols and chernosols, using bioassays with earthworms (Eisenia andrei). Acute toxicity tests and avoidance assays were performed according to standard protocols. Potentially bioavailable concentrations of heavy metals were estimated by quantifying their concentrations in tissues of survival earthworms. The results revealed that soil properties played an important role in the toxicity and bioavailability of heavy metals. In this respect, higher levels of toxicity were detected for the ferralsol. The abundance of 2:1 clay minerals, high fertility and more basic values of pH seem to be very important in the reduction of toxicity levels for earthworms. Organisms exposed to the chernosols were able to uptake higher amount of metals. In that case, higher contents of nutrients in chernosols may have influenced such bioavailability processes. Avoidance responses were the most sensible indicator of toxicity. In the near future, such data can subsidize the establishment of toxic reference concentrations able to reflect the characteristics of important tropical pedological occurrences, supporting the definition of sustainable indicators for using sewage sludge in the tropical agriculture. 相似文献
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Using the tunneling method we derive the Hawking temperature of the nonextremal rotating charged black hole in the Gödel universe of five-dimensional minimal supergravity theory found by Wu. We successfully recovered the tunneling probability of charged Dirac particles and the expected Hawking temperature of the black hole, which is exactly consistent with that obtained by other methods. 相似文献
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Jean-François Exbrayat Wouter Buytaert Edison Timbe David Windhorst Lutz Breuer 《Climatic change》2014,125(2):221-235
Future climate projections from general circulation models (GCMs) predict an acceleration of the global hydrological cycle throughout the 21st century in response to human-induced rise in temperatures. However, projections of GCMs are too coarse in resolution to be used in local studies of climate change impacts. To cope with this problem, downscaling methods have been developed that transform climate projections into high resolution datasets to drive impact models such as rainfall-runoff models. Generally, the range of changes simulated by different GCMs is considered to be the major source of variability in the results of such studies. However, the cascade of uncertainty in runoff projections is further elongated by differences between impact models, especially where robust calibration is hampered by the scarcity of data. Here, we address the relative importance of these different sources of uncertainty in a poorly monitored headwater catchment of the Ecuadorian Andes. Therefore, we force 7 hydrological models with downscaled outputs of 8 GCMs driven by the A1B and A2 emission scenarios over the 21st century. Results indicate a likely increase in annual runoff by 2100 with a large variability between the different combinations of a climate model with a hydrological model. Differences between GCM projections introduce a gradually increasing relative uncertainty throughout the 21st century. Meanwhile, structural differences between applied hydrological models still contribute to a third of the total uncertainty in late 21st century runoff projections and differences between the two emission scenarios are marginal. 相似文献