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451.
Environmental Science and Pollution Research - This study quantifies the effect of real income, financial development, trade openness, and renewable energy consumption on the ecological footprint...  相似文献   
452.
Environmental Science and Pollution Research - The advanced oxidation processes (AOPs), especially sulphate radical (SO4•−)–based AOPs (SR-AOPs), have been considered more...  相似文献   
453.
Environmental Science and Pollution Research - This paper investigates the impact of economic growth, energy consumption, tourism, trade openness, and population density on the ecological...  相似文献   
454.
Seven representative sampling stations were selected from Indus Delta comprising of (1) Keti Bander, (2) Darya Peer, (3) Kharo Chanr, (4) Jati, (5) Shah Bander, (6) Nariri Dhand and (7) Left Bank Outfall Drain (LBOD) near Rupa Mari. The sampling scheme was repeated seven times during 2014–2015 for 1 year. The samples were analysed for temperature, conductivity, pH, hardness, chloride, alkalinity, dissolved oxygen, biological oxygen demand, chemical oxygen demand, sulphate, orthophosphate-P, nitrite-N, nitrate-N, Na, K, Fe, Ni, Cr, Co, Cd, Zn, Cu, Pb and As. The analysis was carried out using standard analytical procedures. A number of parameters crossed the WHO permissible limits and water quality guidelines for aquatic life and indicated pollution within coastal region. Coefficient of correlation (r) among physicochemical parameters and metal ions were examined and a number of parameters did not correlate positively and did not indicate natural origin and may indicate their presence due to human activity. The samples were examined for cluster analysis, and principal component analysis. The samples also indicated the presence of Presumptive Coliform, Faecal coliform and E. coli.  相似文献   
455.
Complex industrial discharges pose certain risks to the ecosystem. This study was aimed at identifying acute and sub-chronic toxicological effects of the textile industry wastewater. The textile wastewater was evaluated for the metals and organic pollutants by atomic absorption spectrophotometer and GC-MS respectively. In vitro genotoxicity and mutagenicity were assessed by Comet assay in peripheral lymphocytes isolated from Ovis aries and Ames test in Salmonella typhimurium strains TA-100 and 102 respectively. Physiological and behavioral changes along with systemic toxicity were determined in Rattus norvegicus albinus following acute and sub-chronic exposure. High amount of heavy metals such as Cr, Pb, Hg, As, and Cd were detected in textile wastewater. Organic pollutants such as 25-deacetoxy cucurbitacin-b, E-14-Hexadecenal, 11-Tricosene, and phthalates were also found. In vitro genotoxicity assessment in lymphocytes showed statistically significant DNA damaging potential of textile wastewater. Textile wastewater also showed significantly higher (p? 0.05) mutagenic potential in Salmonella TA-100 and TA-102 strains than sodium azide and 2-amino anthracycline. Acute exposure of textile wastewater to Rattus norvegicus was associated with several physiological changes and behavioral symptoms. Sub-chronic exposure of textile wastewater in Rattus norvegicus instigated the degeneration and necrosis of epithelial cells in renal tubules, hydropic degeneration and necrosis of hepatocytes, peri-bronchiolar infiltration and emphysema of the alveoli, and the degradation of myocardial cells. This study concludes that the textile wastewater may cause genotoxicity and mutagenicity, result in physiological and behavioral changes upon acute exposure, and inflict various pathological lesions upon sub-chronic exposure.  相似文献   
456.
The combination of nitrogen and plant population expresses the spatial distribution of crop plants. The spatial distribution influences canopy structure and development, radiation capture, accumulated intercepted radiation (Sa), radiation use efficiency (RUE), and subsequently dry matter production. We hypothesized that the sunflower crop at higher plant populations and nitrogen (N) rates would achieve early canopy cover, capture more radiant energy, utilize radiation energy more efficiently, and ultimately increase economic yield. To investigate the above hypothesis, we examined the influences of leaf area index (LAI) at different plant populations (83,333, 66,666, and 55,555 plants ha?1) and N rates (90, 120, and 150 kg ha?1) on radiation interception (Fi), photosynthetically active radiation (PAR) accumulation (Sa), total dry matter (TDM), achene yield (AY), and RUE of sunflower. The experimental work was conducted during 2012 and 2013 on sandy loam soil in Punjab, Pakistan. The sunflower crop captured more than 96% of incident radiant energy (mean of all treatments), 98% with a higher plant population (83,333 plants ha?1), and 97% with higher N application (150 kg ha?1) at the fifth harvest (60 days after sowing) during both study years. The plant population of 83,333 plants ha?1 with 150 kg N ha?1 ominously promoted crop, RUE, and finally productivity of sunflower (AY and TDM). Sunflower canopy (LAI) showed a very close and strong association with Fi (R 2 = 0.99 in both years), PAR (R 2 = 0.74 and 0.79 in 2012 and 2013, respectively), TDM (R 2 = 0.97 in 2012 and 0.91 in 2013), AY (R 2 = 0.95 in both years), RUE for TDM (RUETDM) (R 2 = 0.63 and 0.71 in 2012 and 2013, respectively), and RUE for AY (RUEAY) (R 2 = 0.88 and 0.87 in 2012 and 2013, respectively). Similarly, AY (R 2 = 0.73 in 2012 and 0.79 in 2013) and TDM (R 2 = 0.75 in 2012 and 0.84 in 2013) indicated significant dependence on PAR accumulation of sunflower. High temperature during the flowering stage in 2013 shortened the crop maturity duration, which reduced the LAI, leaf area duration (LAD), crop growth rate (CGR), TDM, AY, Fi, Sa, and RUE of sunflower. Our results clearly revealed that RUE was enhanced as plant population and N application rates were increased and biomass assimilation in semi-arid environments varied with radiation capture capacity of sunflower.  相似文献   
457.
This study was undertaken to develop and validate direct competitive ELISA for the determination of chloramphenicol residues in bovine milk. Antisera and an enzyme-tracer for chloramphenicol were prepared and used to develop an ELISA with inhibition concentrations, IC20 and IC50, of 0.09 and 0.44 ng mL?1, respectively. Milk samples were spiked with standards equivalent to 0, 0.2, 0.3, 0.5, 1.0 &; 1.5 ng mL?1 and extracted in methanol. The mean recoveries were found to be 73–100% with coefficient of variance 7–11%. The decision limit (CCα) and detection capability (CCβ) were calculated as 0.10 and 0.12 ng mL?1, respectively. The results were found comparable with the commercial ELISA, having recoveries of 87 to 100%, CCα 0.09 ng mL?1 and CCβ 0.12 ng mL?1. As per Commission Decision 2002/657/EC, in-house ELISA was further validated by using LC-MS/MS. Mass spectral acquisition was done by using electrospray ionization in the negative ion mode applying single reaction monitoring of the diagnostic transition reaction for CAP (m/z 152, 194 and 257). The calibration curve showed good linearity in concentrations from 0.025 to 1.6 ng mL?1 with correction coefficient 0.9902. The mean recoveries were found to be 88 to 100%. The CCα was calculated as 0.057 ng mL?1 and CCβ 0.10 ng mL?1. Since CCα and CCβ are less than half of the MRPL (0.15 ng mL?1), the test was found suitable for screening and quantification of CAP residues in bovine milk samples. Results of surveillance studies indicated that out of 31 analyzed milk samples, 12.9% samples were found with CAP residues but only 3.2% samples were declared positive with maximum concentration 0.31 ng mL?1, slightly above the MRPL.  相似文献   
458.

Conventional weed management systems have produced many harmful effects on weed ecology, human health and environment. Biological control of invasive weeds may be helpful to minimize these harmful effects and economic losses incurred to crops by weeds. In our earlier studies, plant antagonistic bacteria were obtained after screening a large number of rhizobacteria for production of phytotoxic substances and effects on wheat and its associated weeds under laboratory conditions. In this study, five efficient strains inhibitory to broad-leaved dock and non-inhibitory to wheat were selected and applied to broad-leaved dock co-seeded with wheat both in pot trial and chronically infested field trial. Effects of plant antagonistic bacteria on the weed and infested wheat were studied at tillering, booting and harvesting stage of wheat. The applied strains significantly inhibited the germination and growth of the weed to variable extent. Similarly, variable recovery in losses of grain and straw yield of infested wheat from 11.6 to 68 and 13 to 72.6% was obtained in pot trial while from 17.3 to 62.9 and 22.4 to 71.3% was obtained in field trial, respectively. Effects of plant antagonistic bacteria were also evident from the improvement in physiology and nutrient contents of infested wheat. This study suggests the use of these plant antagonistic bacteria to biologically control infestation of broad-leaved dock in wheat under field conditions.

  相似文献   
459.
In this study water soluble sodium carboxymethyl cellulose (CMC) was blended with high density polyethylene (HDPE) by peroxide-initiated melt compounding technique. The compatibility of the blended polymers were carried out by silane crosslinking agent. A series of blends were prepared by varying the CMC contents up to a maximum of 50 phr. The physical properties of non-crosslinked and crosslinked blends were investigated in detail. FTIR analysis of crosslinked blend confirmed the presence of Si–O–Si and Si–O–C absorption peaks at 1050 and 1159 cm?1. Thermal stability of crosslinked blends improved as compared to its non-crosslinked congener. Rheological study of crosslinked blends illustrated high complex viscosity and dynamic shear storage modulus. The tensile strength of virgin polyethylene was 8.1 MPa whereas the maximum tensile strength of 19.6 MPa was observed in crosslinked blend. Similarly lower deformation was observed in crosslinked blends under static load. Scanning electron microscopy of crosslinked formulations also showed strong adhesion between the polymers interface. The compatibility of HDPE and CMC is attributed to both free radical and condensation reactions.  相似文献   
460.
Journal of Material Cycles and Waste Management - This paper focuses on the performance of oil palm empty fruit bunch (EFB) gasification using a medium-scale downdraft gasifier for power...  相似文献   
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