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The contents of Li, V, P2O5, and Al2O3 in marls and mudstones collected from three different formations, cropping out in northern Iraq, showed that the ratios of Li/Al2O3, V/Al2O3, and P2O5/Al2O3 in these rocks can be used to discriminate environments of deposition of these formations. Relatively high values of the above ratios characterize the deep marine Shiranish environment while lowest values characterize freshwater environment of deposition of the Injana rocks. Despite that marls of the Fatha formation were deposited in marine lagoonal environment, the ratios P2O5/Al2O3 and V/Al2O3 could not be discriminated from the freshwater Injana mudstones. The well-known phenomenon that marine surface water and down to a depth of 50 m almost lacks soluble P explain this behavior. In such water, almost all the soluble P is consumed by surface organism rendering it unavailable for adsorption by the sediments. The high salinity of the lagoonal environment prevented adsorption of soluble V on clay minerals because of its inability to compete with other species of much higher concentrations. 相似文献
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Taura Usman H. Mahzari Pedram Sohrabi Mehran Al-Wahaibi Yahya Farzaneh Sayyed Amir 《Computational Geosciences》2022,26(5):1207-1222
Computational Geosciences - In heavy oil displacement by fluid injection, severe instability can occur due to the adverse mobility ratio, gravity segregation or compositional effects. However, when... 相似文献
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This paper is a presentation of three sources of artifact‐quality chert in Central Anatolia. A previous dearth of research focused on locating and characterizing such raw material sources has incorrectly colored our view of prehistoric economic practices. To remedy this situation, we have conducted a survey of various locales within Central Anatolia to test for the presence of artifact‐quality materials. We make use of Individual Attribute Analysis (IAA) and Energy Dispersive X‐ray Fluorescence (EDXRF) analysis to discriminate among these materials, and suggest their use by the Neolithic occupants of Çatalhöyük through similar analyses of artifactual materials. We argue that the presence and characterization of these new sources allows us to better understand the intricacies of Neolithic practices by illustrating the ways in which the consumption of these materials was variably entwined with the exploitation of other resources, as well as embedded within social relations outside of Central Anatolia. © 2013 Wiley Periodicals, Inc. 相似文献
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Elshafie A AlKindi AY Al-Busaidi S Bakheit C Albahry SN 《Marine pollution bulletin》2007,54(11):1692-1696
Ten fungal species isolated from tar balls collected from the beaches of Oman were tested for their abilities to grow and degrade n-alkanes and crude oil. The abilities of Aspergillus niger, A. ochraceus and Penicillium chrysogenum to degrade n-alkanes (C13-C18), crude oil were compared and their mycelial biomass was measured. Significant differences were found in the utilization of C15, C16, C17 and C18 by the three fungi. Similarly, significant differences we found in the amount of biomass produced by the three fungi growing on C13, C17, C18 and crude oil. The correlation coefficient of biomass and oil utilization was not statistically significant for Aspergillus niger, significant for Aspergillus terreus and highly significant for P. chrysogenum. 相似文献
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Xiaojuan Zou Haifeng Gao Yinsheng Zhang Ning Ma Jianfeng Wu Suhaib Bin Farhan 《水文研究》2021,35(4):e14145
Ice reserve estimates is a fundamental prerequisite for water resources management. We selected the UIB (upper Indus river basin) as study area because it contains the most abundant mid-latitude glaciers outside the polar region, however, the ice reserve estimates remain unclear due to the harsh topography. In this study, we validated the parameters of the GlabTop2 model (Glacier Bed Topography version 2) using the ice thickness measured by GPR (ground-penetrating radar) and compared the “GPR-measured ice thickness and ice bed elevation” versus “the estimated results obtained from GlabTop2.” Integrated with IDW (inverse distance weighted) interpolated results of glaciers of various sizes, a reasonable parametric scheme (τ = 120 kPa and f = 0.8) of GlabTop2 was applied on vast amounts of glaciers in the UIB region. The GlabTop2 estimates indicated that the ice thickness of the UIB varied from 0 to 736.0 ± 110.0 m, with an average value of 74.5 ± 11.2 m. A significant spatial heterogeneity exists in the sub-basins. The Shyok, Shigar and Hunza that contain the most abundant ice reserve. Lesser quantities are stored in the Western Himalaya and Hindu Kush ranges, which account for 11.3 % and 6.7 % of the total ice reserve in the UIB, respectively. A total volume of 1162.4 ± 175.1 km3 of glacier can be converted to 1046.2 ± 157.6 Gt ice reserve; this is 13.6 times the annual average discharge obtained from the outlet of the Besham hydrological station. We aim to present estimates that can provide the baseline information for glaciology study of the Indus river. 相似文献
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Muhammad Nauman Malik Mehdi Murtuza Iqbal Asif Bakar Muhammad Saifullah Abu Brahim Aissa Dk Nur Afiqah Jalwati Puteri Amer Farhan Rafique 《地下水科学与工程》2014,7(4):373-382
In many circumstances involving heat and mass transfer issues, it is considered impractical to measure the input flux and the resulting state distribution in the domain. Therefore, the need to develop techniques to provide solutions for such problems and estimate the inverse mass flux becomes imperative. Adaptive state estimator (ASE) is increasingly becoming a popular inverse estimation technique which resolves inverse problems by incorporating the semi-Markovian concept into a Bayesian estimation technique, thereby developing an inverse input and state estimator consisting of a bank of parallel adaptively weighted Kalman filters. The ASE is particularly designed for a system that encompasses independent unknowns and /or random switching of input and measurement biases. The present study describes the scheme to estimate the groundwater input contaminant flux and its transient distribution in a conjectural two-dimensional aquifer by means of ASE, which in particular is because of its unique ability to efficiently handle the process noise giving an estimation of keeping the relative error range within 10% in 2-dimensional problems. Numerical simulation results show that the proposed estimator presents decent estimation performance for both smoothly and abruptly varying input flux scenarios. Results also show that ASE enjoys a better estimation performance than its competitor, Recursive Least Square Estimator (RLSE) due to its larger error tolerance in greater process noise regimes. ASE’s inherent deficiency of being slower than the RLSE, resulting from the complexity of algorithm, was also noticed. The chosen input scenarios are tested to calculate the effect of input area and both estimators show improved results with an increase in input flux area especially as sensors are moved closer to the assumed input location. 相似文献
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Understanding factors influencing groundwater chemistry in regional groundwater basins is important to prevent groundwater pollution especially in arid areas where rainfall is low and water resources are limited. The present study assesses such factors in the regional, geologically diverse, groundwater basin of Wadi Umairy in Oman. The basin is composed of five different lithostratigraphic units with different hydraulic properties. Water samples (41) have been collected from the different units and analyzed for the major ions. Factor analysis and conventional hydrochemical methods were used to define the factors that have significant impact on the aquifer's hydrochemistry. It was found that evaporation and mineral weathering/dissolution are the main factors defining the groundwater chemistry along the flow path from recharge to discharge zones, whereas anthropogenic activities and alkalinity are found to be of lesser effect, and the latter prevails when the rocks are predominantly monomineralic. It was concluded that in regional groundwater basins, recharge/discharge relations together with the flow scale control the hydrochemistry irrespective of lithological variation in the basin. 相似文献
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Indonesia as an archipelagos country consisting of more than 17,508 islands has a challenging problem in terms of island management and the provisional ocean services to the coastal community. The population growth (especially in coastal areas) followed by declining natural resources caused by overfishing and overexploitation is one of the biggest concerns both for the central and the local governments in Indonesia. Integrated Coastal Zone Management (ICZM) is one of the attempted solutions to overcome these difficulties, however, it is known to be unsatisfactory even after several programs under ICZM have been developed and implemented. Therefore, further facilitation of ICZM programs is necessary in order to benefit to Indonesian governmental management of their islands, coastal areas and oceans. In doing so, ICZM will also make a significant contribution towards the implementation of the Indonesia Global Ocean Observing System (INA-GOOS). This paper aims to review ICZM activities in Indonesia to obtain a better understanding of, and the need for ICZM implementations in support of their policy, sustainability and decision-making process in the direction of INA-GOOS. It is expected that the ICZM implementations will have a high impact on INA-GOOS programs. 相似文献