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41.
Sugar production is a major agro-based industry in India that generates various solid wastes viz. sugarcane trash, bagasse, press mud and bagasse fly ash. This work examines the state-of-the-art in innovative value added products that can be obtained from the transformation of these wastes. Challenges in implementing these waste valorization solutions are also highlighted. It is observed that the extent of research and adoption of these solutions vary considerably. Both industry involvement as well as government encouragement is required in translating the research findings into commercial products.  相似文献   
42.
Large-scale ecosystem restoration efforts, such as those in the Florida Everglades, can be long-term and resource intensive. To gauge success, restoration efforts must have a means to evaluate positive or negative results of instituted activities. Edaphic properties across the Everglades landscape have been determined to be a valuable metric for such evaluation, and as such, a baseline condition from which to make future comparisons and track ecosystem response is necessary. The objectives of this work were to document this baseline condition in the southern most hydrologic unit of the Everglades, Everglades National Park (ENP), and to determine if significant eco-partitioning of soil attributes exists that would suggest the need to focus monitoring efforts in particular eco-types within the ENP landscape. A total of 342 sites were sampled via soil coring and parameters such as total phosphorus (TP), total nitrogen (TN), total carbon (TC), total calcium, total magnesium, and bulk density were measured at three depth increments in the soil profile (floc, 0-10 cm, and 10-20 cm). Geostatistical analysis and GIS applications were employed to interpolate site-specific biogeochemical properties of soils across the entire extent of the ENP. Spatial patterns and eco-type comparisons suggest TC and TN to be highest in Shark River Slough (SRS) and the mangrove interface (MI), following trends of greatest organic soil accumulation. However, TP patterns suggest greatest storages in MI, SRS, and western marl and wet prairies. Eco-partitioning of soil constituents suggest local drivers of geology and hydrology are significant in determining potential areas to focus monitoring for future change detection.  相似文献   
43.
Journal of Material Cycles and Waste Management - The utilization of recycled aggregate (RA) extracted from construction and demolition (C&D) waste contributes to reducing the usage of...  相似文献   
44.
With large influx of freshwater that decreases sea-surface salinities, weak wind forcing of <10 m s−1 and almost always warm (>28°C) sea-surface temperature that stratifies and shallows the mixed layer leading to low or no nutrient injections into the surface, primary production in Bay of Bengal is reportedly low. As a consequence, the Bay of Bengal is considered as a region of low biological productivity. Along with many biological parameters, bacterioplankton abundance and production were measured in the Bay of Bengal during post monsoon (September–October 2002) along an open ocean transect, in the central Bay (CB, 88°E) and the other transect in the western Bay (WB). The latter representing the coastal influenced shelf/slope waters. Bacterioplankton abundances (<2 × 109cells l−1) were similar to those reported from the HNLC equatorial Pacific and the highly productive northern Arabian Sea. Yet, the thymidine uptake rates along CB (average of 1.46 pM h−1) and WB (average of 1.40 pM h−1) were less than those from the northwestern Indian Ocean. These abundances and uptake rates were higher than those in the oligotrophic northwestern Sargasso Sea (<7 × 108 cells l−1; av 1.0 pM h−1). Concentrations of chlorophyll a (chl a), primary production rates and total organic carbon (TOC) were also measured for a comparison of heterotrophic and autotrophic production. In the WB, bacterioplankton carbon biomass equaled ∼ 95% of chl a carbon than just 31% in the CB. Average bacterial:primary production (BP:PP) ratios accounted for 29% in the CB and 31% in the WB. This is mainly due to lower primary productivity (PP) in the WB (281 mg C m−2 d−1) than in the CB (306 mg C m−2 day−1). This study indicates that bacteria–phytoplankton relationship differs in the open (CB) and coastal waters (WB). Higher abundance and contrastingly low bacterial production (BP) in WB may be because of the riverine bacteria, brought in through discharges, becoming dormant and unable to reproduce in salinities of 28 or more psu. Heterotrophic bacteria appear to utilize in situ DOC rather rapidly and their carbon demand is ∼50% of daily primary production. It is also apparent that allochthonous organic matter, in particular in the western Bay, is important for meeting their carbon demand.  相似文献   
45.
Theprevalence and seasonal variation of bacterial indicators of faecal pollution such as total coliform bacteria, faecal coliform bacteria, Escherichia coli and faecal streptococci were investigated in samples of water and beach sand from the four fish landing centres of Thoothukudi. Further the samples were screened for Salmonella to study the reliability of faecal indicator bacteria as an index of human pathogenic bacteria. Total coliform bacteria, faecal coliform bacteria and Escherichia coli were isolated from all four landing centres from undetectable to the maximum detectable level of over Most Probable Number 140 throughout the year with no obvious seasonal variation. Faecal streptococci were also detected in most samples. There was no discernable relationship between faecal indicators and physical parameters. The relationship between faecal indicators and Salmonella was not significant (p > 0.05). The results showed that the coastal waters along Thoothukudi is polluted and presents a potential risk to public for recreational and fishing activities.  相似文献   
46.
The present study deals with the assessment of ambient air quality with respect to respirable suspended particulate matter (RSPM or PM10 < or = 10 microm) and trace metals (Fe, Zn, Cu, Cr Ni, Cd, Mn and Pb) concentrations in RSPM at five locations of Renukoot, an industrial area of Eastern Uttar Pradesh. The 24 hr mean concentrations of PM10 ranged between 69.3 to 118.9 microg m(-3), which is well within the permissible limit (150 microg m(-3)) of national ambient air quality standards (NAAQS) but found higher than the prescribed annual daily limit of US EPA (50 microg m(-3)). The ambient air was mostly dominated by the Fe and least by the Cd among the metal analysed. Murdhawa, a commercial place influenced by vehicular population, is found to be the most polluted area of Renukoot and Dongia nalla (forest area) the least. The ambient air of Murdhawa is rich in Cu and Ni, indicating contribution of mobile sources. The Rammandir a residential place near the industry, is rich in Cd and Cr suggesting contribution of point sources. The Ni concentration is found to be alarmingly high in the air at all the locations except Dongia nallah, when compared with the EC (European Commission) limit (20 ng m(-3)). The Cd concentration is found to be higher only at Rammandir as compared with the EC limit (5 ng m(-3)). Mean concentrations of Zn, Pb and Mn are found to be almost equal in the ambient air of all the locations, suggesting the significance of sources contributing to presence of these metals. Zn, Cu, Pb and Ni having a significant correlation with PM10 indicate the same source contributing these metals as well as PM10. The present study has focused on the quantitative variation in different metals in the PM10, which is extremely harmful due to their toxic and carcinogenic nature.  相似文献   
47.
Journal of Material Cycles and Waste Management - Fused filament fabrication (FFF) based additive manufacturing (AM)&nbsp;process is a widely used and emerging manufacturing process for...  相似文献   
48.
"二噁英"是指一类化学结构和生物特征均有某些相似之处的化合物.这些有毒化合物有几百种,可分为相关的三大类:氯代二苯并-对-二噁英(CDDs),氯代二苯并呋喃(CDFs)和某些多氯代联苯(PCBs).CDDs和CDFs并非与生具有,而是由于人类活动不注意而生成的.天然过程也会产生CDDs和CDFs.  相似文献   
49.
Environmental Science and Pollution Research - Efficient nutrient cycling and adequate sediment bioavailable nutrient supply are considered to be the two most important factors regulating the high...  相似文献   
50.
Environmental Science and Pollution Research - Although water occupies 75% of the earth’s surface, only 0.0067% of the total water is available for human activities. These statistics further...  相似文献   
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