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11.
Mohammad Wasim Mohammad Arif Sajid Iqbal Muhammad Daud 《Geostandards and Geoanalytical Research》2013,37(1):87-93
The International Atomic Energy Agency (IAEA) organised a proficiency test (PT), IAEA‐CU‐2010‐02, for the determination of elements in sewage sludge. The PT sample was analysed by semi‐absolute standardless k0‐instrumental neutron activation analysis (k0‐INAA). Results for seven elements (As, Co, Cr, Fe, Hg, Se, Zn) were submitted to the IAEA by our laboratory. All of our results were scored ‘acceptable’ by the ‘result evaluation criteria’ adopted by the IAEA. The same analytical methodology produced quantitative results for twenty‐six additional elements. In total, thirty‐six elements were determined with uncertainty varying from 4 to 11%. This paper presents the provisional mass fractions of twenty‐six additional elements (Ag, Al, Br, Ca, Ce, Cl, Dy, Eu, Ga, Hf, I, K, La, Mg, Mn, Na, Rb, Sb, Sc, Sm, Ta, Tb, Th, V, U, W) not reported by the IAEA. The analytical methodology was discussed with important sources of spectral, nuclear and fission‐product interferences. It was shown that the important components of uncertainties were the k0 factor, Q0 factor, detector efficiency, mass and counting statistics. The methodology was validated by analysing the IAEA‐S7 reference material. 相似文献
12.
A. Ugur Ozcan Gunay Erpul Mustafa Basaran H. Emrah Erdogan 《Environmental Geology》2008,53(8):1731-1741
The universal soil loss equation (USLE) is an erosion model to estimate average soil loss that would generally result from
splash, sheet, and rill erosion from agricultural plots. Recently, use of USLE has been extended as a useful tool predicting
soil losses and planning control practices by the effective integration of the GIS-based procedures to estimate the factor
values on a grid cell basis. This study was performed for five different lands uses of Indağı Mountain Pass, Cankırı to predict
the soil erosion risk by the USLE/GIS methodology for planning conservation measures in the site. Of the USLE factors, rainfall-runoff
erosivity factor (USLE-R) and topographic factor (USLE-LS) were greatly involved in GIS. These were surfaced by correcting
USLE-R site-specifically using DEM and climatic data and by evaluating USLE-LS by the flow accumulation tool using DEM and
watershed delineation tool to consider the topographical and hydrological effects on the soil loss. The study assessed the
soil erodibility factor (USLE-K) by randomly sampled field properties by geostatistical analysis. Crop management factor for
different land-use/land cover type and land use (USLE-C) was assigned to the numerical values from crop and flora type, canopy
and density of five different land uses, which are plantation, recreational land, cropland, forest and grassland, by means
of reclassifying digital land use map available for the site. Support practice factor (USLE-P) was taken as a unit assuming
no erosion control practices. USLE/GIS technology together with the geostatistics combined these major erosion factors to
predict average soil loss per unit area per unit time. Resulting soil loss map revealed that spatial average soil loss in
terms of the land uses were 1.99, 1.29, 1.21, 1.20, 0.89 t ha−1 year−1 for the cropland, grassland, recreation, plantation and forest, respectively. Since the rate of soil formation was expected
to be so slow in Central Anatolia of Turkey and any soil loss of more than 1 ton ha−1 year−1 over 50–100 years was considered as irreversible for this region, soil erosion in the Indağı Mountain Pass, to the great
extent, attained the irreversible state, and these findings should be very useful to take mitigation measures in the site. 相似文献
13.
14.
Miraj Khan Mohammad Arif Nowrad Ali Mohammad Yaseen Ammar Ahmed Syed Mamoon Siyar 《Arabian Journal of Geosciences》2016,9(5):425
The Eocene rock units of the Qadirpur field, Central Indus Basin (Pakistan), are investigated petrophysically for their detailed reservoir characterization. The different petrophysical parameters determined include the following: true resistivity, shale volume, total porosity, effective porosity, density and neutron porosity, water and hydrocarbon saturation, bulk volume of water, lithology, gas effect, P-wave velocity, movable hydrocarbon index and irreducible water saturation and integrated with different cross-plots. The Eocene reservoirs are excellent with high effective porosity (2–32 %) and hydrocarbon saturation (10–93 %). Among these, the Sui Upper Limestone is an overall a poor reservoir; however, it has some hydrocarbon-rich intervals with high effective porosity and better net pay. All the net pay zones identified show low and variable shale volume (5–30 %). The secondary porosity has added to the total and effective porosities in these reservoirs. The main contributors to the porosity are the chalky, intercrystalline and vuggy/fracture types. The thickness of the reservoirs zones ranges from 4.5 to 62 m. These reservoirs are gas-producing carbonates with almost irreducible water saturation (0.002–0.01) and are likely to produce water-free hydrocarbons. The lower values of moveable hydrocarbon index (0.07–0.9) show that the hydrocarbons are moveable spontaneously to the well bore. The proposed correlation model shows that the reservoirs have an inclined geometry and are a part of an anticlinal trap. 相似文献
15.
Inclusion of synthetic fibers is becoming a routine task in soil reinforcement. The ability of synthetic fibers in controlling the shrinkage cracks in concrete is the main drive to consider its benefits in clay and other soil materials. The polypropylene fibers are nonbiodegradable and can perform well even in aggressive chemical exposure conditions. The direct shear testing is a popular geotechnical approach to assess the shearing strength for a range of soils. This study is aimed at investigating the effect of fiber inclusion on the direct shear response of semi-arid clay soils. This research is conducted using two different types of polypropylene fibers, viz., Fibercast and Fibermesh, having different surface properties on the shear strength envelope and parameters (angle of internal friction and cohesion). The aspect lengths were varied as 6 and 12 mm, and the dosages were varied as 0.2, 0.4, and 0.6 % by weight of the soil. The results were viewed in relation to the fiber type, size, and dose. The soil response and shear resistance measured in consolidated undrained direct shear test is presented for the targeted doses, and the results revealed useful insight compared to unreinforced. The Fibermesh material proved to be the more appropriate fiber additive to typical semi-arid clay soils. The data provides helpful guide for the design geotechnical engineers. 相似文献
16.
This article aims to analyze how private property regimes can co-exist with common property regimes in a coastal area. The case study shows how the dynamics of private property and common property right holders is in creating commitment to make symbiosis in resource use. This is based on a case study in two villages in West Lombok, Indonesia, where pearl-culture as a private property resource exists in a common property regime. This is a successful story in dealing with the tragedy of property rights in the country wherein established institutional arrangement is still absent. Nevertheless, this may be site specific, and fragile if there is no institutional arrangement combining formal and informal rules and involving both formal and informal authorities. To make a robust solution, multilevel solution must be considered: national, local, and community level, with reference to Japan case. 相似文献
17.
This paper is concerned with the modeling of particle transport at the Safaniya sea area. It presents the modeling aspects of a marine environment impact study at the Safaniya offshore facility. The offshore facility has continuous discharges of hypochlorite concentration, sanitary waste water, oily water, brine, and sea cooling water. The dispersion of pollutants in the Safaniya sea area is analyzed with the aid of a particle dispersion model. The dispersion of a continuous discharge from the offshore platform is simulated for typical meteorological conditions during the seasons of winter, spring, summer, and fall. Maximum average pollutant concentrations are obtained at various depths. A time series of pollutant concentration near the location of the discharge is constructed. The sea areas affected by the discharge are computed. The dispersion of a hypochlorite concentrate with concentration of 2 ppm is analyzed. Results indicate that the average chlorine concentration has a maximum of 0.27 × 10−2 ppm. 相似文献
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19.
Toulier Alix Lachassagne Patrick Hendrayana Heru Fadillah Arif Jourde Hervé 《Hydrogeology Journal》2023,31(3):849-851
Hydrogeology Journal - 相似文献
20.
There is growing concern that increasing concentrations of greenhouse gases in the atmosphere have been responsible for global warming through their effect on radiation balance and temperature. The magnitude of emissions and the relative importance of different sources vary widely, regionally and locally. The Indus Basin of Pakistan is the food basket of the country and agricultural activities are vulnerable to the effects of global warming due to accelerated emissions of GHGs. Many developments have taken place in the agricultural sector of Pakistan in recent decades in the background of the changing role of the government and the encouragement of the private sector for investment in new ventures. These interventions have considerable GHG emission potential. Unfortunately, no published information is currently available on GHG concentrations in the Indus Basin to assess their magnitude and emission trends. The present study is an attempt to estimate GHG (CO2, CH4 and N2O) emissions arising from different agro-ecosystems of Indus Basin. The GHGs were estimated mostly using the IPCC Guidelines and data from the published literature. The results showed that CH4 emissions were the highest (4.126 Tg yr^-1) followed by N20 (0.265 Tg yr^-1) and CO2 (52.6 Tg yr^-1). The sources of CH4 are enteric fermentation, rice cultivation and cultivation of other crops. N2O is formed by microbial denitrification of NO3 produced from applied fertilizer-N on cropped soils or by mineralization of native organic matter on fallow soils. CO2 is formed by the burning of plant residue and by soil respiration due to the decomposition of soil organic matter. 相似文献