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991.
Environmental Science and Pollution Research - Cold plasma has been a potent energy-efficient and eco-friendly advanced oxidation technology which has gained attention in recent decades as a...  相似文献   
992.
High speed machining (HSM) of tool steels in their hardened state is emerging as an attractive approach for the mold and die industry due to its potential for significant cost savings and productivity improvement. An experimental study was conducted to investigate the tool wear mechanism and surface integrity in high speed ball nose end milling of hardened AISI A2 tool steel using coated tungsten carbide and polycrystalline cubic boron nitride (PCBN) tools. It is found that coated carbide tools can only be used at low speed (120 m/min) while high content PCBN tools are suitable for HSM range (470 m/min). PCBN tools produce a damage free workpiece with better surface finish and less work hardening. Despite the higher tool cost, HSM with PCBN tools lead to reduction in both total cost and production time per part.  相似文献   
993.
The differentiation between mono- and dichorionic placentation in twin pregnancies is of clinical importance because of the significant difference in perinatal morbidity and mortality between the two, and the increased surveillance indicated in monochorionic gestations. Application of ultrasonography has enabled very precise prenatal determination of chorionicity. While this is best performed in the first trimester when accuracy approaches 100%, even in the third trimester, using a composite cascade of available sonographic features, accuracy has been reported to approach 97%. While two clearly separate placentae or discordant fetal gender conform to dichorionicity, in most twin pregnancies other features need to be assessed to determine chorionicity. The presence of the ‘lambda’ or the ‘T’ sign in the presence of a single placenta, best determined in the first trimester, is the most reliable indicator of chorionicity, with measurements of the inter-twin membrane thickness and counting of the membrane layers being less reliable. In this article, we review the sonographic features that help in the accurate depiction of chorionicity. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
994.
995.
This paper deals with effects of sheep and goat grazing on plant species diversity, species richness and species composition in two important conservation areas of the Western Himalaya; the Valley of Flowers (VOF) National Park and the Great Himalayan National Park (GHNP). The VOF is a completely Protected Area as it is devoid of livestock grazing whereas, 20,000 sheep and goats annually graze in GHNP. Both the National Parks possess sub-alpine and alpine vegetation that is distributed in 13 major habitat types. Present investigations indicate that all the habitat types in VOF are higher in plant species diversity and richness compared to habitat types in GHNP. Similarly, all three eco-climatic zones in VOF are higher in species diversity and richness compared to GHNP. Species diversity also decreases with increasing altitude in both the National Parks. The findings of this study are discussed in the light of the management and conservation of alpine meadows of the Western Himalayas.  相似文献   
996.
A novel single cathode chamber and multiple anode chamber microbial fuel cell design(MAC-MFC)was developed by incorporating multiple anode chambers into a single unit and its performance was checked.During 60 days of operation,performance of MAC-MFC was assessed and compared with standard single anode/cathode chamber microbial fuel cell(SC-MFC).The tests showed that MAC-MFC generated stable and higher power outputs compared with SC-MFC and each anode chamber contributed efficiently.Further,MAC-MFCs were incorporated with different wastewaters in different anode chambers and their behavior in MFC performance was observed.MAC-MFC efficiently treated multiple wastewaters simultaneously at low cost and small space,which claims its candidature for future possible scale-up applications.  相似文献   
997.
Environment, Development and Sustainability - Despite a large number of studies examining the relationship between corporate social responsibility disclosure (CSRD) and corporate financial...  相似文献   
998.
Environment, Development and Sustainability - Urbanization plays a crucial role in the urban landscape dynamics, contributing to numerous ecosystems and urban climate changes. Diurnal variation of...  相似文献   
999.
Instantaneous measurements of equilibrium equivalent concentration of radon (EEC(Rn)) were taken over a period of 1 year in 2004 in a typical house at Amritsar city, located in the northwest part of India. A method based on absolute beta counting subsequent to grab aerosol sampling was used. During that year, EEC(Rn) varied between 1.56B qm(-3) and 22.77B qm(-3) with average value of 8.76Bb qm(-3). EEC(Rn) decreased with the transition from winter to summer and vice versa, having a negative correlation with outdoor temperature. The use of mechanical ventilation, under normal living conditions during summer, caused an extra decrease in the concentrations. The variations with temperature and mechanical ventilation are discussed. Some major issues related to the uncertainties in dose calculations caused by the lack of knowledge of equilibrium factor and ignoring the effect of life style on the radon and its progeny concentrations are discussed.  相似文献   
1000.
Nano silver (Agn) is employed as an active antimicrobial agent, but the environmental impact of Agn released from commercial products is unknown. The quantity of nanomaterial released from consumer products during use should be determined to assess the environmental risks of advancement of nanotechnology. This work investigated the amount of silver released from three different types of fabric into water during washing. Three different types of fabric were loaded with chemically synthesized Ag nanoparticles and washed repeatedly under simulated washing conditions. Variable leaching rates among fabric types suggest that the manufacturing process may control the release of silver reaching the waste water treatment plants. In an attempt to recover the Agn for reutilization and to save it from polluting water, the effluents from the wash were efficiently treated with bacterial strains. This treatment was based on biosorption and was very efficient for the elimination of silver nanoparticles in the wash water. The process ensured the recovery of the Agn leached into the effluent for reutilization, thus preventing environmental repercussions.  相似文献   
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