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A novel, simple, fast, and efficient ionic liquid‐based dispersive liquid–liquid extraction (IL‐DLLE) has been applied to extract and remove Congo Red (CR; a carcinogenic textile dye) from aqueous solutions. In this methodology a binary solution, containing the extraction solvent (1‐hexyl‐3‐methylimmidazolium bis(trifluormethylsulfonyl) imid) and a suitable disperser solvent, was rapidly injected into the water sample containing CR dye. Therewith, a cloudy solution was formed, and most of the dye molecules were extracted into fine IL droplets and removed from aqueous phase. The effects of pH, type, and amount of IL, initial concentration of the dye, type and volume of the dispersant, and concentrations of salt on the extraction of the dye were studied. Experimental surveys were also accomplished for recovery of the IL by applying a reverse dispersive liquid–liquid extraction using acidic stripping solutions.  相似文献   
2.
This paper presents a neural network approach to determine 2D inverse modeling of a buried structure from gravity anomaly profile. The results of the applied neural network method are compared with the results of two other methods, least-squares minimization and the simple method. Sphere, horizontal cylinder and vertical cylinder and their gravity effects are considered as the synthetic models and the synthetic data, respectively. The synthetic data are also corrupted with noise to evaluate the capability of the methods. Then the Dehloran bitumen map in Iran is chosen as a real data application. Anomaly value of the cross-section, which is taken from the gravity anomaly map of Dehloran bitumen, is very close to those obtained from these methods.  相似文献   
3.
This paper describes the application of magnetotelluric (MT) method to investigate Björkö impact structure located at west of Stockholm, Sweden. This structure has formed in crystalline rocks ca. 1.2 Ga ago and located relatively close to the district heating infrastructure of the Stockholm region, as the largest district heating system in Europe. Since impact structures mostly contain fractured rock volumes in the form of breccia formations, the occurred brecciation zones in this region are more favorable potential targets for geothermal investigations. The main objective is evaluating the capability of the study area to have potential for geothermal resources by mapping the subsurface structure. To image electrical characteristic of underground layers, 1D and 2D bimodal inversions of TE and TM modes of MT data are performed. The results are also compared with the outputs of the inversion of the determinant data (yielding a direction-independent average of the subsurface conductivity) along the same profiles, proving good accordance of the outputs. The processed resistivity sections at depth along with measuring various rock physical properties across two drilled boreholes at Björkö and Midsommar islands localized two conductors at depths of 1 km and from 2.5 to 4.5 km, which may be attributed to be a potential zone for geothermal energy retrieval.  相似文献   
4.
A harmonic wave group single run seakeeping procedure is developed, validated and compared with regular wave and transient wave group procedures, using an unsteady Reynolds averaged Navier–Stokes solver, although all procedures can be also implemented using experiments or potential flow. Incoming waves are generated by linear superposition of potential solution for a number of component waves. The regular wave procedure requires multiple runs, whereas single run procedures obtain the response amplitude operators (RAO) for a range of frequencies at a fixed speed, assuming linear ship response. The transient wave group procedure provides continuous RAO curves, while the harmonic wave group procedure obtains discrete transfer functions without focusing. Results are presented for heave and pitch response amplitudes and phases for the DTMB model 5512 in head waves. Verification and validation studies are performed for the transient wave group procedure. Validation is achieved at the average interval of 9.54 (%D). Comparisons of the procedures show that the harmonic wave group procedure is the most efficient, saving 75.8% on the computational cost compared with the regular wave procedure. Error values from all procedures are similar at 4 (%D). Harmonic wave group results are validated for a wide range of the Froude numbers, with satisfactory results.  相似文献   
5.
The central Iranian volcanic-sedimentary belt in Kerman province of Iran that is located within the Urumieh-Dokhtar magmatic arc zone is chosen to integrate diverse evidential layers for mineral potential mapping. The studied area has high potential of mineral occurrences especially porphyry copper, and the prepared potential maps aim to outline new prospect zones for further investigation. Two evidential layers including the downward continued map and the analytic signal of filtered magnetic data are generated to be used as geophysical plausible traces of porphyry copper occurrences. The low values of the resistivity layer acquired from airborne frequency domain electromagnetic data are also used as an electrical criterion in this study. Four remote sensing evidential layers including argillic, phyllic, propylitic, and hydroxyl alterations are extracted from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) images in order to map the altered areas associated with porphyry copper deposits. The Enhanced Thematic Mapper Plus (ETM+) images are used as well to prepare iron oxide layer. Since potassic alteration is generally the mainstay of copper ore mineralization, the airborne potassium radiometry data is used to explore both phyllic and potassic alteration. Finally, the geochemical layers of Cu/B/Pb/Zn elements and the main geochemical component responsible for ore mineralization extracted from principal component analysis are included in the integration process to prepare final potential maps. The conventional and the extended version of VIKOR method (as a well-known algorithm in multi-criteria decision making problems) produced two mineral potential maps, and the results were compared with the ones acquired from prevalent methods of the index overlay and fuzzy logic operators of sum and gamma. The final mineral potential maps based upon desired geo-data set indicate adequately matching of high potential zones with previous working and active mines of copper deposits.  相似文献   
6.
Nowadays, one of the most important methodologies to reduce the destructive effects of severe earthquakes on structures is the use of energy dissipation devices (EDDs). In this paper, a new configuration of special truss moment frame (STMF) systems including EDDs is theoretically proposed to improve their seismic performance. Such an improvement is achieved by provision of bending performance in these frames. For this purpose, the devices called buckling resistant braces (BRBs) are located at the side of beam‐column connections as the top and bottom members of truss‐girders. In this context, a five‐bay nine‐story STMF is designed using the damage and energy concepts recently proposed in the literature. To show the effectiveness of the proposed system with respect to the similar recently presented STMFs, this frame is then subjected to non‐linear static and non‐linear time‐history analyses under several ground motion records in order to survey on its seismic performance. Subsequently, such engineering demand parameters as lateral displacement, inter‐story drift ratio, overturning moment and shearing forces of stories, residual deformations and maximum time‐history displacement at roof level, as well as the process of plastic hinges formation are investigated. The results show the effectiveness of proposed configuration of EDDs used to improve the seismic safety of STMFs. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
7.
Arabian Journal of Geosciences - This paper describes a general framework of incorporating magnetic data as prior information in the modeling of an iron deposit based on sparse drilling boreholes....  相似文献   
8.
This paper describes the application of the knowledge-based fuzzy logic method to integrate various exploratory geo-dataset in order to prepare a mineral prospectivity map (MPM) for copper exploration. Different geophysical layers which are derived from the magnetic and the electrical surveys, along with the ones extracted from the background geology (i.e., lithology, fault and alteration) and geochemical data are incorporated in such process. Seridune copper deposit located in the Kerman province of Iran is the case study to delineate its high potential zones of Cu-bearing mineralization for drilling additional boreholes. Four layers from the magnetic data involving upward continuation, analytic signal, reduced to pole and pseudo gravity are assigned in the multi-disciplinary geo-dataset to locate the intrusive complexes responsible for Cu mineralization. The apparent resistivity, chargeability and sulfide factor layers acquired from geo-electrical data are also included in the final preparation of MPM. Then the normalized weights of seven geophysical, three geological and one geochemical evidential layers as main criteria are determined based upon the knowledge of expert decision makers. Fuzzy operators (i.e., Sum and Gamma) are applied to integrate these exploratory features. To evaluate the performance and applicability of the approach, the productivity of the drilled boreholes (Cu concentration multiplied by ore thickness) are used to validate the produced MPMs. It is shown that an optimum correlation coefficient of 0.86 exists between the MPM values and Cu productivity criterion along drilled boreholes.  相似文献   
9.
Natural Resources Research - In this work, a quantifier-guided ordered weighted averaging (OWA) method was employed for mineral potential mapping (MPM) in Nowchun Cu–Mo prospect, SE Iran. The...  相似文献   
10.
This paper describes the usage of clustering methods including self-organizing map (SOM) and fuzzy c-means (FCM) which are applied to prepare mineral prospectivity map. Different evidential layers, including geological, geophysical, and geochemical, to evaluate Now Chun copper deposit located in the Kerman province of Iran are used. Clustering approaches are used to reduce the dimension of 13 feature vectors derived from different layers. At first, Geospatial Information Systems (GIS) is employed to analyze and integrate different layers, and the area under study is prioritized to five classes. Then, the SOM as an unsupervised classification method is carried out to classify this area into five clusters. Produced clusters are compared with GIS prospect map, while the SOM results are matched with the GIS output. The main reason to use the FCM is that a vector belongs simultaneously to more than one cluster so that membership values of each cluster can be mapped. As a consequence, clusters generated by the SOM and FCM are considerably matched with five-class-map of the GIS approach. The chosen cluster as a high potential location to additional drilling is matched to the main alteration and faults zone. To validate generated clusters for mineral potential mapping, geological matching of study area and selected proper cluster can be a satisfactory way. Finally, clustering methods can be a very fast approach to interpret the area under study.  相似文献   
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