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491.
Mohd Kafeel Ahmad Ansari Hong‐Bo Shao Shahid Umar Altaf Ahmad Shahid Hussain Ansari Muhammad Iqbal Gary Owens 《洁净——土壤、空气、水》2013,41(2):195-201
Ten Indian mustard (Brassica juncea L.) genotypes were screened for their phytoremediation potential for arsenic (As) contaminated water under laboratory‐controlled conditions. The genotypes were grown in a hydroponic chamber for 20 days in 250‐mL beakers containing As‐contaminated water. During plant development, changes in plant growth, biomass, and total As were evaluated. Of the 10 genotypes (Pusa Agrani, BTO, Pusa Kranti, Pusa Bahar, Pusa Bold, Pusa Basant, Pusa Jai Kisan, Arka Vardhan, Varuna, and Vaibhav) Pusa Jai Kisan was the most effective in phytoremediating As‐contaminated water under hydroponic conditions. This will provide new information for Indian mustard genotypes for phytoremediating As‐contaminated soils. 相似文献
492.
Current Status of Textile Industry Wastewater Management and Research Progress in Malaysia: A Review
Textile industry is one of the fastest growing industries and significantly contributes to the economic growth in Malaysia. However, this industry also has high water consumption and subsequently produces high discharge rate of wastewater with high load of contaminants. The release of dyes into the environment during textile fiber dyeing and finishing processes is a main source of water pollution. Individual wastewater treatment through physical, biological, or chemical method is often very costly and results in large amount of sludge. Thus, there is a need to look for alternative treatment processes that covers from pre to post wastewater treatment stage. This paper reviews the current scenario with respect to textile industry effluent in Malaysia and technologies available for the treatment of the effluent. Prospects, challenges, and recommendations for future direction as well as on‐going research works dedicated to the treatment of textile wastewater are also reviewed in detail. 相似文献
493.
Mahtab Ahmad Deok Hyun Moon Kyoung Jae Lim Christopher L. Shope Sang Soo Lee Adel R. A. Usman Kwon-Rae Kim Jeong-Hun Park Seung-Oh Hur Jae E. Yang Yong Sik Ok 《Environmental Earth Sciences》2012,67(4):1023-1031
Military shooting range soils contaminated by heavy metals have been subjected to remediation efforts to alleviate the detrimental effects of exposure on humans and the surrounding environment. Waste materials can be used as cost-effective soil amendments to immobilize heavy metals in contaminated soils. In this study, naturally occurring lime-based waste materials including egg shells, oyster shells, and mussel shells were assessed for their effectiveness toward heavy metal immobilization in military shooting range soil in Korea. Soil was treated in batch leaching experiments with 0, 2.5, 5, 10, and 15% of each lime-based waste material. The results showed that the lime-based waste materials effectively reduced water-soluble Pb at an application rate of 2.5% by weight of the soil. Increase in soil pH from 6.6 to 8.0 was considered to be the main chemistry of Pb immobilization, which was supported by the formation of insoluble Pb species at high pH values as confirmed by the visual MINTEQ thermodynamic model. In contrary, water-soluble Cu was increased in the lime-based waste material-treated soils when compared to the untreated soil. This was likely attributed to the formation of soluble Cu?CDOC (dissolved organic carbon) complexes as all lime-based waste materials applied increased DOC contents in the soil. Therefore, care must be taken in selecting the appropriate amendment for immobilizing metals in shooting range soils. 相似文献
494.
The Kirsh gneiss dome: an extensional metamorphic core complex from the SE Arabian Shield 总被引:1,自引:1,他引:0
Ahmad M. Al-Saleh 《Arabian Journal of Geosciences》2012,5(2):335-344
A number of gneiss-cored domes and antiforms are exposed along the regional strike-slip Najd fault system in the Arabian Shield and the eastern desert of Egypt. The mode of origin is still controversial, although plausible comparisons with modern metamorphic core complexes were made in some well-studied areas. The Kirsh dome is located within the major Ar Rika shear zone and consists of a core of orthogneiss/migmatite and an envelope of paragneisses with locally abundant kyanite-bearing quartzites. The dome is surrounded by the low-grade metasediments of the Murdama Group and is bound from the south by a low-angle dip-slip fault. Beyond the southern strand of the Ar Rika Fault is the Kibdi Basin which hosts unmetamorphosed sediments belonging to the Jibalah Group; this group occupies scattered pull-apart basins closely associated with releasing bends along the Najd fault system. Little dating has been done on the gneiss domes of the Arabian Shield; however, recent dates from similar structures in the eastern desert and Sinai range from 580 to 620?Ma. A similar, albeit younger 40Ar/39Ar age of 557?±?15?Ma was obtained from a biotite paragneiss south of Jabal Kirsh; this age difference probably represent the time interval it took the Kirsh rocks to cool below the biotite closure temperature and would place a lower age limit for the dome. The Kirsh dome occupies an extensional zone between left-stepping faults; movement within this zone might have caused enough decompression to trigger fluid-absent melting in the middle crust especially as the rocks cross the biotite dehydration solidus. Diapiric ascent aided by strike-slip dilatancy pumping led to the emplacement of the Kirsh rocks in their present position within the Murdama Group metasediments. 相似文献
495.
Omar Alkouri Husaini Omar Mohammed Abu Shariah Ahmad Rodzi Shattri Mansor Zainuddin Md. Yusof 《Journal of the Geological Society of India》2012,79(5):515-524
Limestone bedrock topography has complex phenomena and highly relief subsurface topography due to the presence of karstic
features. Geotechnical and environmental problems arise whenever foundations are established on the surface of the limestone
bedrock or within the overburden soils. Geographical information system (GIS) and remote sensing are emerging as powerful
techniques widely applicable in natural resources management to detect land use changes and devise strategies based on these
changes. The study focuses on using aerial photography for the detection of changes and effects of mining on geomorphology,
especially the use of sequential images that allows to detect changes taken place from time to time, by using. Volumetric
Surface Movement Spatiotemporal Data Model (VSMSDM) application has been employed to create karst terrain surface movements
and visualized 3D information in the Virtual Geographical Information Systems (VGIS). VSMSDM application was implemented by
developing prototype of visualization system using with integrated time in the TIN structure. The data have been collected
from aerial photography in 1981 and 2004, and the results displayed that the proposed data model is able to view the changing
in karst topography to detect significant landscapes and landforms changes. 相似文献
496.
We study the motions of an infinitesimal mass in the Sitnikov four-body problem in which three equal oblate spheroids (called primaries) symmetrical in all respect, are placed at the vertices of an equilateral triangle. These primaries are moving in circular orbits around their common center of mass. The fourth infinitesimal mass is moving along a line perpendicular to the plane of motion of the primaries and passing through the center of mass of the primaries. A relation between the oblateness-parameter ‘A’ and the increased sides ‘ε’ of the equilateral triangle during the motion is established. We confine our attention to one particular value of oblateness-parameter A=0.003. Only one stability region and 12 critical periodic orbits are found from which new three-dimensional families of symmetric periodic orbits bifurcate. 3-D families of symmetric periodic orbits, bifurcating from the 12 corresponding critical periodic orbits are determined. For A=0.005, observation shows that the stability region is wider than for A=0.003. 相似文献
497.
Ahmad Pouya 《Comptes Rendus Geoscience》2005,337(6):581-588
In an earlier paper, it has been shown that for a heterogeneous block of finite size, under linear boundary pressure conditions, a symmetric and positive definite tensor, denoted here by , exists, which relates the mean flux to the mean gradient of pressure in the block. In this paper, the conditions of constant boundary flux are first defined. Then it is shown that, under these conditions also, a symmetric and positive definite tensor, denoted , exists, which relates the mean flux to the mean pressure gradient. It is then shown that and respectively give the equivalent permeability in the direction of mean gradient and of mean flux. The directional permeability values given by are shown to be smaller than . To cite this article: A. Pouya, C. R. Geoscience 337 (2005). 相似文献
498.
Three polar plumes were studied using Skylab Mg x and O vi data. The plumes lie within the boundaries of a polar coronal hole. We find that the mean temperature of the plumes is about 1.1 × 106 K and that they have a small vertical temperature gradient. Densities are determined and found consistent with white light analyses. The variation of density with height in the plumes is compared with that expected for hydrostatic equilibrium. As is the case for other coronal features, polar plumes will be a source of solar wind if the magnetic field lines are open. On the basis of the derived plume model and estimates of the numbers of plumes in polar coronal holes, it appears that polar plumes contain about 15% of the mass in a typical polar hole and occupy about 10% of the volume.Skylab Solar Workshop post-doc appointee 1975–1976. The Skylab Solar Workshops are sponsored by NASA and NSF and managed by the High Altitude Observatory, National Center for Atmospheric Research. 相似文献
499.
Chee Kong Yap Ahmad Ismail Abdul Rahim Ismail Soon Guan Tan 《湿地科学》2006,4(4):247-252
The distribution and concentrations of Cd, Cu, Pb and Zn were determined in the gills and remaining soft tissues of Perna viridis collected from 12 geographical sites ( 10 from the west and 2 from the east coastal waters) of Peninsular Malaysia. All samples showed that the levels of Cd, Pb and Zn were generally higher in the gill than those in the remaining soft tissues. These results could be due to the fact that gills are the first organ of metal accumulation and larger surface area with mucus sheets in the organ. Since the mussel gill is a better accumulator of Cd, Pb and Zn of ambient seawater than remaining soft tissue, it is a potential indicator of ambient levels of dissolved metals in the ambient seawater. However, further validations based on laboratory conditions are needed. 相似文献
500.