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931.
Landfill leachates are not adequately treated in traditional wastewater treatment plants, on account of their problematic peculiarities: i.e., dark colour, high concentration of recalcitrant pollutants and COD, and high toxicity. In this work, 19 biomasses (15 autochthonous and 4 allochthonous) were exploited in biosorption treatment for the remediation of a leachate (influent) and the effluent coming from the biological oxidation with activated sludge and nitrification–denitrification treatment. The effects of the initial pH, the biomass amount, and the medium for the biomass pre-culture were considered. The best configuration was: pH 5, 5 g L??1 biomass cultivated on STY medium. Eventually, the two most effective biomasses, Cunninghamella bertholletiae MUT 2861 and Aspergillus fumigatus MUT 4050, were used in consecutive 2 h cycles in a batch biosorption experiment. The effectiveness of the treatment decreased in subsequent cycles in terms of decolourisation (31–15%). COD, Cl?, SO42?, total N, and toxicity were removed mainly in the second cycle of treatment (up to ??36, ??12, ??15, ??17 and ??49%, respectively). The results suggest that the effluent toxicity was basically due to uncoloured substances, which were mainly removed after coloured molecules.  相似文献   
932.
Education infrastructure issues have been one of the most important topics in developing countries that have difficulty reserving money for education infrastructure needs, especially Turkey. Development plans have a crucial role in meeting school infrastructure needs in Turkey. Generally, the expropriation method has been used for land transitions from private to public ownership. However, scarcity of monetary resources for such land transitions and legal/technical deficiencies delays the process. The main objectives of this paper are to respond to the need of the education sector by using land management tools and to identify the most suitable land management tool for allocating basic and primary school lands free of charge. Current trends, education indicators, management responsibility and financial resources, statistical and economical information, education infrastructure needs, and qualitative-quantitative characteristics of the pupils in the Turkish education system are analyzed based on national and international reports. Then, the property right problems experienced in the process of allocating school lands are defined. Methods of transferring school lands to public ownership are examined, and the benefit-cost relationships are revealed. Land readjustment (LR) would make an important contribution to planning decisions and the implementation stage in the sustainable management of school lands.  相似文献   
933.
Atmospheric dust is considered to be the major cause of poor air quality due to its contribution to high particulate levels, but their interaction with the acidic gases helps in controlling the level of SO2 and NO2 through ambient neutralization reactions. In the present study, the interaction of acidic gases such as SO2 and NO2 with alkaline dust was investigated during October, 2013–July, 2014 at a site named as Babarpur located at the Trans-Yamuna region of Delhi. The concentration of SO2 ranged from 10 to 170 μg/m3 with an average of 36 μg/m3 while that of NO2 ranged from 15 to 54 μg/m3 with an average of 26?±?8 μg/m3. The results were observed to be well within the National Ambient Air Quality Standard (NAAQS) limits prescribed by the Central Pollution Control Board (CPCB). The average concentrations of SO2 during day and night time were recorded as 31?±?18 and 43?±?53 μg/m3 respectively while the mean concentrations of NO2 during day and night time were recorded as 26?±?7 and 27?±?12 μg/m3 respectively. A positive correlation between SO42? and NO3? was also observed indicating their secondary aerosol formation. In aerosol phase, average concentrations of SO42? during day and night time were 3.9?±?0.3 and 6.5?±?2.3 μg/m3 respectively while that of NO3? were 9.5?±?1.5 and 7.3?±?0.5 μg/m3 respectively. Molar ratios of Ca2+/SO42?, NH4+/SO42?, and NH4+/NO3? were observed as 8, 5, and 1.7 during daytime and 1.5, 0.4, and 0.8 during nighttime respectively. Such molar ratios confirmed high concentrations of sulphate (SO4)2? and low concentrations of nitrate (NO3?) during night time, thereby indicating different pathway of aerosol formation during day and night time. Surface morphology and elemental composition of aerosol samples showed various oval, globular, and platy shapes where the diameter varied from few nm to ~5 μm depending on their precursors. There were certain shapes like grossularite, irregular aggregate, grape-like, triangular, and flattened which indicate the crustal origin of aerosols and their possible role in SO2 and NO2 adsorption.  相似文献   
934.
Haryana plain is the drainage divide between the Ganga plain in the east and the Indus plain in the west. Being a part of the Himalayan foreland, its geomorphology, sedimentation processes, and tectonism are broadly controlled by the Himalayan tectonics. Soil and geomorphological mapping in Haryana plain bring out geomorphic features such as paleochannels, various active drainage patterns, and landforms such as old fluvial plains, floodplains, piedmonts, pediments, terminal fans, and eolian plains. Based on the degree of soil development, and Optical stimulated luminescence (OSL) ages, the soil-geomorphic units were grouped into six members (QIMS-I to VI) (Quaternary Indus Morphostratigraphic Sequence) of a morphostratigraphic sequence: QIMS-VI 9.86–5.38 Ka, QIMS-V 5.38–4.45 Ka, QIMS-IV 4.45–3.60 Ka, QIMS-III 3.60–2.91 Ka, QIMS-II <?2.91–1.52 Ka, and QIMS-I <?1.52 Ka. OSL chronology of different geomorphic features suggests six episodes of tectono-geomorphic evolution in the region since 10 Ka. Neotectonic features such as nine faults, two lineaments, and five fault-bounded tectonic blocks have been identified. Independent tilting and sagging of the blocks in response to neotectonics have resulted in modification of landforms, depositional processes, and hydro-geomorphology of the region. Major rivers like the Yamuna, the Ghaggar, and the Sutlej show different episodes of shifting of their courses. Lineament controlled few extinct channels have been recorded between 20 and 25 m depth below the surface in the ground-penetrating radar (GPR) profiles. These buried channels are aligned along the paleo-course of the Lost Saraswati River interpreted from the existing literature and hence are considered as the course of the lost river. Seven terminal fans have been formed on the downthrown blocks of the associated faults. The Markanda Terminal Fan, the first of such features described, is indeed a splay terminal fan and was formed by a splay distributary system of the Markanda River. Association of three terminal fans of different ages with the Karnal fault indicates the segment-wise development of the fault from west to east. Also, comparison with other such studies in the Ganga plain to further east suggests that the terminal fans formed by streams with distributary drainage pattern occur only in semiarid regions as in the present area and thus are indicators of semiarid climate/paleoclimate. Though the whole region is tectonically active, the region between the Rohtak fault and Hisar fault is most active at present signified by the concentration of earthquake epicenters.  相似文献   
935.
Fracture is one of the most important factors through the whole process of low-permeability reservoir development. Biandong oilfield is a typical low-permeability fractured sandstone reservoir, and has stepped into high water cut stage; thus, the waterflooding effect is poor. Therefore, many contradictions such as high moisture content, decreasing production speed, and low recovery efficiency are becoming increasingly prominent, which have seriously hindered the sustainable development, and need to be solved urgently. However, few such studies on reservoir characterization in low-permeability fractured sandstone reservoir have been conducted in China. In this study, through comprehensive analysis on reservoir characterization and sedimentary environment, significant results are achieved. Three types of fracture occurrence are identified; they are high-angle fracture, low-angle fracture, and horizontal fracture, respectively. Two types of reservoir pore (primary porosity and secondary porosity) are recognized based on thin-section observation and analysis. The diagenetic stage of Biandong oilfield are divided into three stages, early A, early B, and late A, respectively. Finally, a regional discrete fracture network model is established with Fisher’s algorithm based on three-dimensional geological model. All the research results presented above can make a significant instructing function for making reservoir development plan and improving recovery efficiency.  相似文献   
936.
The provenance of the Upper Cretaceous Nubia sandstones from four vertical sections along Qena-Safaga and Qena-Quseir roads in central Eastern Desert of Egypt was investigated based on their modal composition and geochemical data. The Nubia sandstone samples are abundant in quartz content with low feldspar and lithic fragments. Their average modal composition (Q94.2F1.3R4.5) classifies them as quartz arenites with subordinate quartz wackes which is consistent with geochemistry data. The average CIA, CIW, PIA, and Th/U ratio values revealed that the intensity of weathering in the studied areas was similar, varying from moderate to intensive weathering, and may reflect low-relief and warm humid climatic conditions in the source area. The ICV (<?1) and SiO2/Al2O3 ratio (>?5) indicate that the Nubia sandstones are texturally and mineralogically mature. The petrographical and geochemical analyses suggest that the Nubia sandstones were mainly derived from felsic (granitic) and/or recycled sand sources. The major element-based multidimensional tectonic discrimination diagrams suggested the Nubia sandstones were deposited in a passive continental margin of a syn-rift basin. This result agreed with the general geology of central Eastern Desert of Egypt during the Upper Cretaceous.  相似文献   
937.
Modulus of subgrade reaction is one of the required design parameters in any structural analyses of shallow foundations. However, the constant values of modulus of subgrade reaction that are determined from either from literature studies or the results of plate load tests, regardless of magnitude of soil’s displacement under design loads, have been used in structural designs of foundations. In this study, the results of 43 published full-scale field plate load tests in cohesionles soils were gathered to expose any variation in the values of modulus of subgrade reaction as soil’s displacement increases. Extensive finite element (FE) analyses were carried out while the results of FE analyses were compared with actual measured results of field load tests. The results of analyses indicated that both the modulus of subgrade reaction decrease with increase in magnitude of displacement of soils and internal forces of a design of structural frame is higher with the values of modulus of subgrade reaction that are sensitive to soil’s displacement are implemented into analyses. Therefore, structural dimensions of any structure with the constant values of modulus of subgrade reaction would not be a precise engineering solution.  相似文献   
938.
This research is conducted as part of a Spanish International Cooperation Agency project with the aim to investigate the sustainable protection of Tunisian coastal zones, as in the case of Beni Khiar and Dar Chaabane coasts (Hammamet Gulf) separated by Oued El Kebir river. The sedimentary dynamic of these beaches is studied in order to identify the main causes responsible for their erosion by the use of different approaches of in situ measurements and numerical methods. Geophysical surveys and sedimentary analyses have demonstrated that sediments are finer and less carbonated from Beni Khiar to Dar Chaabane. Then, the shoreline mapping of several missions of aerial photos has illustrated a mean shoreline retreat between 3 and 4 m/year. In terms of sand volume, a sediment loss more than 30,000 m3/year at Dar Chaabane has been observed since the hill lake structures were built within Oued El Kebir river in 1996. Finally, modelled hydrodynamic and sedimentary patterns have illustrated the refraction of waves in deep water close to shoals and a high-energy concentration along Dar Chaabane coast. The sediment transport direction is mainly of NE-SW induced by ESE-SE wave-driven alongshore current. Results provided by these approaches have shown the importance of Oued El Kebir sediment yield in supplying the neighbouring beaches. Changes in sedimentary dynamics are affected by the modification of hydrodynamic patters caused by the presence of hydrological dams and the implementations of hotels close to the shoreline. This finding underlines the key role of Oued El Kebir fluvial activity in controlling the equilibrium of beaches and their sensitivity to coastal managements induced by man activities, as in the case of the most Mediterranean beaches.  相似文献   
939.
Previous studies showed that the climatic processes drive the streamflow of the inland river in Northwest China. However, it is difficult to quantitatively assess the climatic-hydrological processes in the ungauged mountainous basins because of the scarce data. This research developed an integrated approach for multi-temporal scale modeling the climatic-hydrological processes in data-scarce mountain basins of Northwest China by combining downscaling method (DM), backpropagation artificial neural network (BPANN), and wavelet regression (WR). To validate the approach, we also simulated the climatic-hydrological processes at different temporal scales in a typical data-scarce mountain basin, the Kaidu River Basin in Northwest China. The main results are as follows: (i) the streamflow is related with regional climatic change as well as atmosphere-ocean variability, (ii) the BPANN model well simulated the nonlinear relationship between the streamflow and temperature and precipitation at the monthly temporal scale, and (iii) although the annual runoff (AR) appears to have fluctuations, there are significant correlations among AR, annual average temperature (AAT), annual precipitation (AP), and oscillation indices, which can be simulated by equations of WR at different temporal scales of years.  相似文献   
940.
This work depends on integrated high-resolution calcareous plankton nannofossil and foraminiferal biostratigraphic analyses for three Upper Cretaceous-Lower Paleogene successions at Farafra-Abu Minqar area, Western Desert, Egypt. These sections are distributed in a north-south geologic profile as follows: El Aqabat, North Gunna, and Abu Minqar. Lithostratigraphically, four formations are recorded in the study area, namely, Khoman (at base), Dakhla, Tarawan, and Esna (at top). In the north at El Aqabat section, Khoman Formation (carbonate facies) is only represented which changes partially toward the south to Dakhla Formation (siliciclastic facies). In the extreme south at Abu Minqar section, it changes completely into siliciclastic facies of Dakhla Formation. Biostratigraphically, seven calcareous nannofossil and eleven planktonic foraminiferal zones represent the Late Cretaceous-Early Paleogene are identified. Based on the occurrence or missing of these zones accompanied with the field criteria resulted in detecting four tectonic events. These tectonic events took place at the Cretaceous/Paleogene (K/Pg), the Danian/Selandian (D/S), the Selandian/Thanetian (S/T), and the Paleocene/Eocene (P/E) boundaries. These tectonic events are related to the impact of the Syrian Arc System. Four sequence boundaries (SB1, SB2, SB3, and SB4) are defined in the Late Cretaceous-Early Paleogene sequence in the Farafra-Abu Minqar area.  相似文献   
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