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Yu Xinran Ahmadinia Masoud Shariatipour Seyed M. Lawton Don Osadetz Kirk Saeedfar Amin 《Natural Resources Research》2020,29(4):2735-2752
Natural Resources Research - Carbon capture and storage is part of Canada’s climate change action plan to reduce greenhouse gas emissions. The Containment and Monitoring Institute Field... 相似文献
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A. Mahmood M.Sc. Ph.D. M. Athar M.Sc. M.Phil. Ph.D. D.Sc. 《International Journal of Environmental Science and Technology》2008,5(1):135-139
Cross-inoculation experiments were conducted in the greenhouse to test the rhizobia isolated from nodules of seven tree legumes for their effectiveness in Vigna mungo plants. The tree legumes included Albizia lebbeck, Dalbergia sissoo, Leucaena leucocephala, Pithecellobium dulce, Prosopis cineraria, Prosopis glandulosa and Prosopis juliflora, all growing under arid environment. Rhizobia from these legumes formed nodules on the roots of Vigna mungo except isolates from Albizia lebbeck. Dry weight and nitrogen contents of Vigna mungo plants increased significantly (P<0.05) in response to cross inoculation as compared to uninoculated control. Rhizobia from Leucaena leucocephala and Prosopis glandulosa showed significant increase in dry weight (P<0.05) and nitrogen contents (P<0.05) than other inoculated treatments. The natural rhizobia of wild tree legumes growing under arid environment show higher tolerance to prevailing adverse conditions like salt stress, elevated temperatures and drought. These rhizobia may be used to inoculate wild as well as crop legumes cultivated in reclaimed desert lands. These rhizobia may have specific traits that can be transferred to other rhizobia through genetic engineering tools. The cross infection of agriculturally important legumes with isolates from wild legumes may prove a useful means of increasing nitrogen contents within these plants. 相似文献
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S. Mahmood A. Ahmed A. Hussain M. Athar 《International Journal of Environmental Science and Technology》2005,2(3):193-199
Variability among populations was analyzed in five provenances of Acacia nilotica from spatially variable habitats. Populations of A. nilotica developed in response to their habitat conditions. The level of variability was significantly high among the populations. Phenotypic variability was extremely high for leaf and stipular spine characteristics. The nature of morphological variability for vegetative traits appeared environmentally controlled. The differentiation of leaf and stipular spine expression seems to have an adaptive significance for the species in terms of water economy. Although, seed and pod characteristics are genetically controlled showing a lower proportion of variability but these traits supported r and k-selection that may allow the species to survive under a wide array of contrasting habitats. The study suggested that populations of A. nilotica are differentiated in relation to the heterogeneity of environment. These populations became adapted to their habitat through the variability of morphological expressions. The morphologically differentiated populations of the species had allowed them to maintain themselves in a wide array of environmental situations enabling A. nilotica to occupy ample ecological ranges. 相似文献
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Tensionless–frictionless interaction of flexible annular foundation with a transversely isotropic multi‐layered half‐space 下载免费PDF全文
Morteza Eskandari‐Ghadi Ghasem Gorji‐Bandpey Azizollah Ardeshir‐Behrestaghi Seyed Masoud Nabizadeh 《国际地质力学数值与分析法杂志》2015,39(2):155-174
A transversely isotropic multi‐layered half‐space, with axis of material symmetry perpendicular to the free surface, supports a flexible either annular or solid circle foundation. The contact area of the foundation and the half‐space is considered to be both frictionless and tensionless. The foundation is assumed to be affected by a vertical static axisymmetric load. Detailed analysis of the interaction of these two systems with different thickness of layers is the target of this paper. With the use of ring load Green's functions for both the foundation and the continuum half‐space, an integral equation accompanied with some inequalities is introduced to model the complex BVP. With the incorporation of ring‐shape FEM, we are capable of capturing both regular and singular solution smoothly. The validity of the combination of the analytical and numerical method is proved with comparing the results of this paper with a number of benchmark cases of both linear and nonlinear interaction of circular and annular foundation with half‐space. Some new illustrations are presented to portray the aspect of the anisotropy and layering of the half‐space. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Hamid Geranian Seyed Hassan Tabatabaei Hooshang H. Asadi Emmanuel John M. Carranza 《Natural Resources Research》2016,25(2):145-159
In this contribution, we used discriminant analysis (DA) and support vector machine (SVM) to model subsurface gold mineralization by using a combination of the surface soil geochemical anomalies and earlier bore data for further drilling at the Sari-Gunay gold deposit, NW Iran. Seventy percent of the data were used as the training data and the remaining 30 % were used as the testing data. Sum of the block grades, obtained by kriging, above the cutoff grade (0.5 g/t) was multiplied by the thickness of the blocks and used as productivity index (PI). Then, the PI variable was classified into three classes of background, medium, and high by using fractal method. Four classification functions of SVM and DA methods were calculated by the training soil geochemical data. Also, by using all the geochemical data and classification functions, the general extension of the gold mineralized zones was predicted. The mineral prediction models at the Sari-Gunay hill were used to locate high and moderate potential areas for further infill systematic and reconnaissance drilling, respectively. These models at Agh-Dagh hill and the area between Sari-Gunay and Agh-Dagh hills were used to define the moderate and high potential areas for further reconnaissance drilling. The results showed that the nu-SVM method with 73.8 % accuracy and c-SVM with 72.3 % accuracy worked better than DA methods. 相似文献
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Emad Zolqadr Seyed Shahaboddin Yasrobi Mohammad Norouz Olyaei 《Geomechanics and Geoengineering》2016,11(1):1-12
This study surveys the performance of temporary soil nail walls with a maximum height of 29.3 m in the Yas project, located in Tehran. Some numerical models, with various modelling approaches, were developed using finite element software and the proper modelling approaches were specified and verified.The modelling results were analysed and compared with the in situ monitored data. The results demonstrate the model’s horizontal deformations are generally greater than the in situ monitored values. To decrease the differences between models and monitored results, the effect of variations of the soil parameters had been surveyed and the limits of needed variations were specified. 相似文献
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