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41.
The present study were made to estimate the avian fauna in terms of species richness and diversity and guild structure in forest habitats of Nainital district of Uttarakhand (350–2.450 m asl; 29° N). Field studies were conducted during January 2007 to December 2008. Total 43, 62 and 42 species were recorded from, Haldwani, Bhowali and Nainital forest habitats. Results indicate the species relationship between Bird species richness (BSR) and elevation sections (forest habitats) was not decline simultaneously along elevation; it shows hump shaped. BSR varied considerably along elevational gradient (43 to 62 species), was highest (62 species) at mid elevation (Mixed pine forest, 1.350–1.700 m asl) and decreased (20 species) at high elevation (Conifer forest, 1900–2450 m asl). It seems that mid altitude bulge is not caused by the presence of a group of mid altitude specialists but rather that there is an overlap in the distribution of low land and high elevation specialists at this altitude. A checklist of 79 avian species has also produced of Nainital district forest habitats. It is suggested that this study provide a base line structure for further study on species distribution in different forest habitats and along different elevation section in Western Himalayas (India).  相似文献   
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This article reports the results of an experimental study undertaken to investigate the effect of spatial arrangement of assembly board and parts bin in the normal work area on work-cycle time in manual assembly tasks. Operator performance was measured in terms of average work-cycle time taken to complete a laboratory-simulated manual assembly task. Results showed that both location and distance factors had significant effects on work-cycle time. Effect of the size of parts was also investigated in the study. Average observed work-cycle times were compared with the methods–time measurement (MTM) values. Repetitive manual assembly tasks are common in industry and are thought to lead to musculoskeletal disorders. The results of this research are important for ergonomic design of the workplace for assembly tasks, which would help to enhance operators’ efficiency.  相似文献   
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Environmental Science and Pollution Research - Environmental pollution caused by carbon emissions is an emerging issue to study among researchers. The nexus between environmental pollution and...  相似文献   
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Environmental Science and Pollution Research - In this work, waste cooking palm oil (WCPO)-based carbon nanotubes (CNTs) with encapsulated iron (Fe) nanoparticles have been successfully produced...  相似文献   
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Lignin and its effects on litter decomposition in forest ecosystems   总被引:1,自引:0,他引:1  
Lignin is a major component of plant litter. In this review, we found lignin comprises a complex class of organic compounds whose concentration differs greatly both between and within plant species. There are many analytical methods for detecting the composition and structure of lignins. As lignins are enormously complex compounds, chemical assay is difficult and different methods vary with the results. Lignin plays a significant role in the carbon cycle, sequestering atmospheric carbon into the living tissues of woody perennial vegetation. It has also great effects on nitrogen dynamics of forest ecosystems as well as other ecological processes. Lignin is one of the most slowly decomposing components of dead vegetation, contributing a major fraction of the material that becomes humus as it decomposes. Lignin is highly correlated with decomposition of litter. Thus, there is evidence that the lignin concentration is a more influential factor than the other chemical concentrations, in determining the rate of leaf litter decomposition of different forest ecosystems. Although a great number of researchers have addressed lignin's role in litter decomposition, still there are many aspects of lignin biogeochemistry that are not known. This lack of information hinders complete amalgam of lignin effects on litter decomposition processes and dynamics of nutrient cycling.  相似文献   
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This article proposed and tested a multilevel and interactional model of individual innovation in which weekly moods represent a core construct between context, personality, and innovative work behavior. Adopting the circumplex model of affect, innovative work behavior is proposed as resulting from weekly positive and high‐activated mood. Furthermore, drawing on the Big Five model of personality and cognitive appraisal theory, openness to experience and support for innovation are proposed as individual and contextual variables, respectively, which interplay in this process. Openness to experience interacts with support for innovation leading to high‐activated positive mood. Furthermore, openness interacts with these feelings leading to greater levels of innovative work behavior. Overall, the model entails a moderated mediation process where weekly high‐activated positive mood represents a crucial variable for transforming contextual and individual resources into innovative outcomes. These propositions were tested and supported using a diary methodology and multilevel structural equation modeling, on the basis of 893 observations of innovative work behavior and moods nested in 10 weekly waves of data. This information was collected from 92 individuals of diverse occupations employed in 73 distinct companies. Theoretical and practical implications are discussed. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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Phytoaccumulation of heavy metals by aquatic plants   总被引:14,自引:0,他引:14  
Three aquatic plants were examined for their ability to remove heavy metals from contaminated water: parrot feather (Myriophylhum aquaticum), creeping primrose (Ludwigina palustris), and water mint (Mentha aquatic). The plants were obtained from a Solar Aquatic System treating municipal wastewater. All the three plants were able to remove Fe, Zn, Cu, and Hg from the contaminated water. The average removal efficiency for the three plant species was 99.8%, 76.7%, 41.62%, and 33.9% of Hg, Fe, Cu, and Zn, respectively. The removal rates of zinc and copper were constant (0.48 mg/l/day for Zn and 0.11 mg/l/day for Cu), whereas those of iron and mercury were dependent on the concentration of these elements in the contaminated water and ranged from 7.00 to 0.41 mg/l/day for Fe and 0.0787 to 0.0002 mg/l/day for Hg. Parrot feather showed greater tolerance to toxicity followed by water mint and creeping primrose. The growth of creeping primrose was significantly affected by heavy metal toxicity. The selectivity of heavy metals for the three plant species was the same (Hg>Fe>Cu>Zn). The mass balance preformed on the system showed that about 60.45-82.61% of the zinc and 38.96-60.75% of the copper were removed by precipitation as zinc phosphate and copper phosphate, respectively.  相似文献   
50.
Environmental Chemistry Letters - Metal nanoparticles have found applications in many fields such as molecular diagnostics, electronic devices and environmental remediation. Nonetheless,...  相似文献   
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