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961.
Environmental Geochemistry and Health - Unfortunately, in the original publication of the article, Prof. Yong Sik Ok’s affiliation was incorrectly published. The author’s affiliation is...  相似文献   
962.
This paper focuses on the spatial distributional profiles of different species of the important micronutrient element, nitrogen (nitrite, nitrate and total nitrogen) in various coral-reef sedimentary environment of Lakshadweep Archipelago. The relative abundance of the three forms of nitrogen was in the order, total-N???nitrate-N???nitrite-N. Relatively very low levels of nitrite in the different microenvironments of the islands are an indication of a higher rate of nitrification, so as to produce thermodynamically most stable form of nitrogen, namely nitrate under the condition of well-oxygenated shallow coastal/lagoon waters. A lagoon-ward enrichment pattern of total nitrogen in the lagoon transects of Agathy, Minicoy, Kadamath and Kiltan Islands also reflected the fact that the rate and space available for nitrogen fixation in shallow zones of the lagoon are high. Further, the nitrogenous waste materials produced from the reefs and surrounding environments have limited exchange with the sea, and all these factors, together with the organic nitrogen retention capacity of sediment types, contribute to total nitrogen.  相似文献   
963.
Many advancements have been introduced to tackle spatial and temporal structures in data. When the spatial and/or temporal domains are relatively large, assumptions must be made to account for the sheer size of the data. The large data size, coupled with realities that come with observational data, make it difficult for all of these assumptions to be met. In particular, air quality data are very sparse across geographic space and time, due to a limited air pollution monitoring network. These “missing” values make it difficult to incorporate most dimension reduction techniques developed for high-dimensional spatiotemporal data. This article examines aerosol optical depth (AOD), an indirect measure of radiative forcing, and air quality. The spatiotemporal distribution of AOD can be influenced by both natural (e.g., meteorological conditions) and anthropogenic factors (e.g., emission from industries and transport). After accounting for natural factors influencing AOD, we examine the spatiotemporal relationship in the remaining human influenced portion of AOD. The presented data cover a portion of India surrounding New Delhi from 2000–2006. The proposed method is demonstrated showing how it can handle the large spatiotemporal structure containing so much missing data for both meteorologic conditions and AOD over time and space.  相似文献   
964.
The transportation of hazardous materials by road is an utmost necessity of the world for the societal benefits, but at the same time the activity is inherently dangerous. Incidents involving hazardous material (hazmat) cargo particularly the class-2 materials can lead to severe consequences in terms of fatalities, injuries, evacuation, property damage and environmental degradation. The rationale behind considering class-2 hazmats is that they pose the greatest danger to the people and property along the transport route because of their storage condition on the transport vessel. They are stored either in pressurized vessels or in cryogenic containers. Any external impact due to collision may cause catastrophic failure of transport vessels, known as BLEVE (Boiling Liquid Expanding Vapour Explosion) with devastating consequences. Further, any continuous release from containment may cause what is known as ‘Unconfined Vapour Cloud Explosion’ (UVCE). Historically frequency of BLEVE occurrence is of the order of 1 × 10−6 per year or less, but other release scenarios e.g. a large vapour or liquid leaks are more probable and could also have devastating effects on the surrounding population. As such, the paper discussed various event scenarios and the consequences taking examples of a class-2.1 material (1,3 butadiene) and another class-2.3 (ammonia) hazmat. Comparative analysis suggests that per ton basis a rupture of ammonia tanker gives rise to larger impact areas and poses larger lethality risks compared to 1,3 butadiene as far as toxic effects are concerned. Besides, from fireball fatality on similar basis propylene causes higher consequence distance than LPG followed by ethylene oxide and 1,3 butadiene. The impact zone study results may be utilized as inputs for identifying the potential vulnerable area on a GIS enabled map, along a designated State highway route passing through an important industrial corridor in western India.  相似文献   
965.
Environmental Science and Pollution Research - Soil contamination by heavy metals is one of the major abiotic stresses that cause retarded plant growth and low productivity. Among the heavy metals,...  相似文献   
966.
Environmental Science and Pollution Research - This study intends to examine the impact of ICT diffusion, globalization, financial development, government effectiveness, and economic growth on...  相似文献   
967.
ABSTRACT

Vertical axis wind turbine (VAWT) is an economic and widely used energy converter for converting wind energy into useful form of energy, like mechanical and electrical energy. For efficient energy conversion in low wind speed and to have improved power coefficient of asymmetric blade VAWT, selection of optimum blade thickness is needed thus entailing its detailed investigation with respect to different operating wind speed conditions. Present study methodically explores the impact of thickness to chord (t/c) ratio on aerodynamic performance of a three bladed asymmetrical blade H-Darrieus VAWT at different low wind speed conditions by using 2D unsteady CFD simulations. The optimal t/c is obtained on the basis of maximum power coefficient and average moment coefficient of the turbine. The aerodynamic performance curves are obtained at different operating and t/c conditions and the performance insights are corroborated with the findings from the flow physics study to come to some concrete conclusions on the effects of the thickness to chord ratio. The present study identifies large blade curvature to create a large diverging passage on the blade suction surface as the prominent reason for aerodynamic performance drop at a high t/c ratio.  相似文献   
968.
Global scarcity of freshwater has been gearing towards an unsustainable river basin management and corresponding services to the humans. It needs a holistic approach, which exclusively focuses on effective river water quality monitoring and quantification and identification of pollutant sources, in order to address the issue of sustainability. These days, rivers are heavily contaminated due to the presence of organic and metallic pollutants released from several anthropogenic sources, such as industrial effluents, domestic sewage, and agricultural runoff. It is astonishing to note that even in many developing countries, most of these contaminants are carried through open drains, which enter river premises without proper treatment. Such practice not only devastates riverine ecosystem but also gives rise to deadly diseases, such as minimata and cancer in humans. Considering these issues, the present study develops a novel approach towards simultaneous identification of major sources of pollution in the rivers, along with critical pollutants and locations using an advanced hierarchical cluster and multivariate statistical analysis. A systematic approach has been developed by agglomerating both R-mode and Q-mode analysis, which develops monoplots, two-dimensional biplots, rotated component matrices, and dendrograms (using “SPSS” and “Analyse It” software) to reveal relationships among various quality parameters to identify the pollutant sources along with clustering of critical sampling sites and pollutants. A case study of the Ganges River Basin of India has been considered to demonstrate the efficacy and usefulness of the model by analyzing 85 open drains. Both organic and metallic pollutants are analyzed simultaneously as well as separately to get a holistic understanding of all the relationships and to broaden the perspective of water characterization. Results provide a comprehensive guidance to the policy makers and water managers to optimize corrective efforts, minimize further damage, and improve the water quality condition to ensure sustainable development of the river basin.  相似文献   
969.
Rising global population would force farmers to amplify food production substantially in upcoming 3–4 decades. The easiest way to increase grain production is through expanding cropping area by clearing uncultivated land. This is attained by permitting deadly loss of carbon (C) stocks, jeopardizing ecosystem biodiversity and deteriorating environmental quality. We aim to propose key agronomical tactics, livestock management strategy and advance approaches for aquaculture to increase productivity and simultaneously reduce the environmental impacts of farming sector. For this, we considered three major sectors of farming, i.e. agriculture, fishery and dairy. We collected literatures stating approaches or technologies that could reduce GHG emission from these sectors. Thereafter, we synthesized strategies or options that are more feasible and accessible for inclusion in farm sector to reduce GHG emission. Having comprehensively reviewed several publications, we propose potential strategies to reduce GHG emission. Agronomic practices like crop diversification, reducing summer fallow, soil organic carbon sequestration, tillage and crop residue management and inclusion of N2-fixing pulses in crop rotations are some of those. Livestock management through changing animals’ diets, optimal use of the gas produced from manures, frequent and complete manure removal from animal housing and aquaculture management strategies to improve fish health and improve feed conversion efficiency could reduce their GHG emission footprint too. Adapting of effective and economic practices GHG emission footprint reduction potential of farming sector could make farming sector a C neutral enterprise. To overcome the ecological, technological and institutional barriers, policy on trade, tax, grazing practice and GHG pricing should be implemented properly.  相似文献   
970.
Journal of Material Cycles and Waste Management - In this study, we developed a one-pot wet ball-milling method for the recovery of highly pure copper wire, poly(vinyl chloride) (PVC) coating, and...  相似文献   
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