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241.
Nasution MA Yaakob Z Ali E Tasirin SM Abdullah SR 《Journal of environmental quality》2011,40(4):1332-1339
Palm oil mill effluent (POME) is highly polluting wastewater generated from the palm oil milling process. Palm oil mill effluent was used as an electrolyte without any additive or pretreatment to perform electrocoagulation (EC) using electricity (direct current) ranging from 2 to 4 volts in the presence of aluminum electrodes with a reactor volume of 20 L. The production of hydrogen gas, removal of chemical oxygen demand (COD), and turbidity as a result of electrocoagulation of POME were determined. The results show that EC can reduce the COD and turbidity of POME by 57 and 62%, respectively, in addition to the 42% hydrogen production. Hydrogen production was also helpful to remove the lighter suspended solids toward the surface. The production of Al(OH)XHO at the aluminum electrode (anode) was responsible for the flocculation-coagulation process of suspended solids followed by sedimentation under gravity. The production of hydrogen gas from POME during EC was also compared with hydrogen gas production by electrolysis of tap water at pH 4 and tap water without pH adjustment under the same conditions. The main advantage of this study is to produce hydrogen gas while treating POME with EC to reduce COD and turbidity effectively. 相似文献
242.
Carrying Capacity of the Environment (CCE) provides a useful measure of the sustainable development of a region. Approaches that use integrated assessment instead of measurement can lead to misinterpretation of sustainable development because of confusion between Environmental Stress (ES) indexes and CCE indexes, and the selection of over-simple linear plus models. The present paper proposes a comprehensive measurement system for CCE which comprises models of natural resources capacity, environmental assimilative capacity, ecosystem services capacity, and society supporting capacity. The corresponding measurable indexes are designed to assess CCE using a carrying capacity surplus ratio model and a vector of surplus ratio of carrying capacity model. The former aims at direct comparison of ES and CCE based on the values of basic indexes, and the latter uses a Euclidean vector to assess CCE states. The measurement and assessment approaches are applicable to Strategic Environmental Assessment (SEA) and environmental planning and management. A case study is presented for Ningbo, China, whereby all the basic indexes of ECC are measured and the CCE states assessed for 2005 and 2010. 相似文献
243.
Khan MA Ram M Jha P Ahmad MM Alam P Kamaluddin Ali A Kiran U Abdin MZ 《Journal of environmental biology / Academy of Environmental Biology, India》2011,32(1):51-55
A broad screening protocol, covering the most general phytochemical groups of compounds, was developed on the basis of high performance thin layer chromatography (HPTLC). A total of six TLC systems, comprising three derivatization reagents, two stationary phases and two mobile phases, were included. The screening method was applied for the identification of biomarkers in the chickpea plant exposed to cadmium and chromium. The biomarkers were selected on the basis of significant changes (0.26-4.6 fold) in concentration levels of phytochemicals. Totally, five different amino acids, three organic acids, one sulphur containing compound and one sugar were identified as biomarkers in chickpea exposed heavy metal. 相似文献
244.
Simon W. Townsend Markus Zöttl Marta B. Manser 《Behavioral ecology and sociobiology》2011,65(10):1927-1934
Socio-demographic factors, such as group size and their effect on predation vulnerability, have, in addition to intrinsic
factors, dominated as explanations when attempting to understand animal vigilance behaviour. It is generally assumed that
animals evaluate these external factors visually; however, many socially foraging species adopt a foraging technique that
directly compromises the visual system. In these instances, such species may instead rely more on the acoustical medium to
assess their relative risk and guide their subsequent anti-predator behaviour. We addressed this question in the socially
foraging meerkat (Suricata suricatta). Meerkats forage with their head down, but at the same time frequently produce close calls (‘Foraging’ close calls). Close
calls are also produced just after an individual has briefly scanned the surrounding environment for predators (‘Guarding’
close calls). Here, we firstly show that these Guarding and Foraging close call variants are in fact acoustically distinct
and secondly subjects are less vigilant (in terms of frequency and time) when exposed to Guarding close call playbacks than
when they hear Foraging close calls. We argue that this is the first evidence for socially foraging animals using the information
encoded within calls, the main adaptive function of which is unrelated to immediate predator encounters, to coordinate their
vigilance behaviour. In addition, these results provide new insights into the potential cognitive mechanisms underlying anti-predator
behaviour and suggest meerkats may be capable of signalling to group members the ‘absence’ of predatory threat. If we are
to fully understand the complexities underlying the coordination of animal anti-predator behaviour, we encourage future studies
to take these additional auditory and cognitive dimensions into account. 相似文献
245.
Osborne TZ Bruland GL Newman S Reddy KR Grunwald S 《Environmental monitoring and assessment》2011,183(1-4):395-408
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
246.
Al-Mutairi NZ Al-Attar MA Al-Rukaibi FS 《Environmental monitoring and assessment》2011,183(1-4):65-75
This study was carried out in metropolitan Kuwait with a sound level meter to assess peak hour and off-peak hour noise level. In local/collector streets, noise ranged between 56.0 to 79.2 dBA and 55.3 to 76.4 dBA; in arterial streets, 62.3 to 89.2 dBA and 59.6 to 78.9 dBA; and in freeways, 66.7 to 94.8 dBA and 64.9 to 89.1 dBA during peak and off-peak hour respectively. Values were higher than their prescribed standards which may pose a significant impact on quality of life. Findings of this research have shown that the level of traffic-generated noise pollution in Kuwait urban area is high enough to adversely affect the human health and well-being of its residents. Over 1,400 subjects responded to a randomly administered survey that assessed the physical health, personal well-being, and mental health. People residing in neighborhoods exposed to higher noise levels have significantly higher stress and noise annoyance levels and also adversely affected their sense of well-being. In the responder analysis, those people living in quiet neighborhoods had significantly higher mean scores in general health (35 points higher, p < 0.05), sense of vitality (30 points higher, p < 0.05), and mental health (20 points higher, p < 0.05) when compared to the other group. In addition, the component scores of stress and noise sensitivity for the participants living in quiet neighborhoods had significantly lower values (30 points lower and 59 points lower, respectively) than that of the participants living in noisy neighborhood. With the rapid expansion of the infrastructures in metropolitan Kuwait, it is virtually definite that traffic noise will shortly assume a dangerous dimension, and will be a ground of escalating fear for both the public and liable policy-makers. The quality of life in metropolitan Kuwait will certainly be negatively affected. 相似文献
247.
Rubenstein LZ Vivrette R Harker JO Stevens JA Kramer BJ 《Journal of Safety Research》2011,42(6):493-499
Background
Falls are a common, serious, and often unrecognized problem facing older adults. The objective of this study was to provide an initial clinical and statistical validation for a public health strategy of fall risk self-assessment by older adults using a Fall Risk Questionnaire (FRQ).Methods
Adults age 65 + (n = 40) were recruited at a Los Angeles Veterans Affairs (VA) medical facility and at a local assisted living facility. Participants completed the FRQ self-assessment and results were compared to a “gold standard” of a clinical evaluation of risks using the American/British Geriatrics Society guidelines to assess independent predictors of falls: history of previous falls, fear of falling, gait/balance, muscle weakness, incontinence, sensation and proprioception, depression, vision, and medications. For the comparison, we used an iterative statistical approach, weighing items based on relative risk.Results
There was strong agreement between the FRQ and clinical evaluation (kappa = .875, p < .0001). Individual item kappa values ranged from .305-.832. After dropping one FRQ item (vision risk) because of inadequate agreement with the clinical evaluation (kappa = .139, p = .321), the final FRQ had good concurrent validity.Conclusions
The FRQ goes beyond existing screening tools in that it is based on both evidence and clinical acceptability and has been initially validated with clinical examination data. A larger validation with longitudinal follow-up should determine the actual strength of the FRQ in predicting future falls. 相似文献248.
A. Grov H.E.Z. OpsvikR.K. Eckhoff 《Journal of Loss Prevention in the Process Industries》2011,24(5):552-557
Electrical apparatus for use in the presence of explosive gas atmospheres has to be specially designed to prevent the apparatus from igniting the gas. Flameproof design is one of several options, and one requirement is then that any holes and slits in the enclosure wall be designed to prevent a possible gas explosion inside the enclosure from being transmitted to an explosive gas cloud outside it. Current standards (IEC) require that joint surfaces have a surface roughness of <6.3 μm. Any damaged joint surface has be restored to this quality. The present investigation has demonstrated that flame gap surfaces in flameproof electrical apparatuses can suffer considerable mechanical and corrosive damage before the flame gaps no longer function satisfactorily. In some cases very significant mechanical surface damage in fact improves the gap performance. This indicates that current high costs of repairing and replacing flameproof electrical apparatus in process plants offshore and onshore can be reduced considerably without any increase of the explosion risk. 相似文献
249.
Forensic fingerprinting and source identification of the 2009 Sarnia (Ontario) oil spill 总被引:2,自引:0,他引:2
Wang Z Yang C Yang Z Sun J Hollebone B Brown C Landriault M 《Journal of environmental monitoring : JEM》2011,13(11):3004-3017
This paper presents a case study in which integrated forensic oil fingerprinting and data interpretation techniques were used to characterize the chemical compositions and determine the source of the 2009 Sarnia (Ontario) oil spill incident. The diagnostic fingerprinting techniques include determination of hydrocarbon groups and semi-quantitative product-type screening via gas chromatography (GC), analysis of oil-characteristic biomarkers and the extended suite of parent and alkylated PAH (polycyclic aromatic hydrocarbon) homologous series via gas chromatography-mass spectrometry (GC-MS), determination and comparison of a variety of diagnostic ratios of "source-specific marker" compounds, and determination of the weathering degree of the spilled oil, and whether the spilled oil hydrocarbons have been mixed with any other "background" chemicals (biogenic and/or pyrogenic hydrocarbons). The detailed chemical fingerprinting data and results reveal the following: (1) all four samples are mixtures of diesel and lubricating oil with varying percentages of diesel to lube oil. Both samples 1460 and 1462 are majority diesel-range oil mixed with a smaller portion of lube oil. Sample 1461 contains slightly less diesel-range oil. Sample 1463 is majority lubricating-range oil. (2) The diesel in the four diesel/lube oil mixture samples was most likely the same diesel and from the same source. (3) The spill sample 1460 and the suspected-source sample 1462 have nearly identical concentrations and distribution patterns of target analytes including TPHs, n-alkane, PAHs and biomarker compounds; and have nearly identical diagnostic ratios of target compounds as well. Furthermore, a perfect "positive match" correlation line (with all normalized ratio data points falling into the straight correlation line) is clearly demonstrated. It is concluded that the spill oil water sample 1460 (#1, from the water around the vessel enclosed by a boom) matches with the suspected source sample 1462 (#3, from the vessel engine room bilge pump). (4) From the n-alkane and PAH analysis, it appears that the oil in the spill sample 1460 is slightly more weathered in comparison with sample 1462. The minor differences in fingerprints of two samples were most likely caused by weathering effects. (5) Sample 1461 (#2, from the vessel engine room bilge) and sample 1463 (#4, from the vessel bilge waste collection tank) demonstrated significantly different fingerprints and diagnostic ratios of target compounds from that of spill sample 1460. This was caused most likely by percentages of diesel to lube oil in these two samples different from that in spill sample 1460. 相似文献
250.
Ivonne Bedei Karl-Philipp Gloning Luc Joyeux Matthias Meyer-Wittkopf Daria Willner Martin Krapp Alexander Scharf Jan Degenhardt Kai-Sven Heling Peter Kozlowski Kathrin Trautmann Kai M. Jahns Annegret Geipel Ismail Tekesin Michael Elsässer Lucas Wilhelm Ingo Gottschalk Jan-Erik Baumüller Cahit Birdir Andreas Schröer Felix Zöllner Aline Wolter Johanna Schenk Tascha Gehrke Alicia Spaeth Roland Axt-Fliedner 《黑龙江环境通报》2023,43(2):183-191