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Singh  Sonal  Patra  Nihar Ranjan 《Acta Geotechnica》2020,15(6):1619-1636
Acta Geotechnica - This paper presents a procedure for evaluating the load–displacement behavior of tapered piles under static axial compressive loads. The response of tapered piles under...  相似文献   
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The Paleogene sections of Kutch are the reference for the regional chronostratigraphic units of India. The ages of these dominantly shallow marine carbonates are mainly based on larger benthic foraminifera (LBF). The taxonomic revisions of the LBF and the progressively refined shallow benthic zonations (SBZ) have necessitated the present study on updating the stratigraphy of the area. The sedimentation in Kutch commenced with the deposition of volcaniclastics in terrestrial environments in the Paleocene. The marine transgression in SBZ 5/6 deposited finer clastics and carbonates, designated as Naredi Formation, in early Eocene. There is no evidence of marine Paleocene in Kutch. A major hiatus spanning SBZ 12 to SBZ 16 was followed by the development of a carbonate platform and deposition of Harudi Formation – Fulra Limestone during the Bartonian, SBZ 17. The hiatus corresponds to a widespread stratigraphic break in Pakistan and India to Australia, referred as the ‘Lutetian Gap.’ The Maniyara Fort Formation is assigned to SBZ 22 B and SBZ 23, and its age is revised to Chattian. Climate played a major role in building up of the Paleogene stratigraphic succession of Kutch, the carbonates formed during the warming intervals and the stratigraphic gaps were in the intervening cooling periods.  相似文献   
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This paper presents the effect of initial placement conditions and flooding stress (vertical compressive stress at flooding) on the collapse potential of remoulded loess. Compacted specimens of loess were tested in a one-dimensional consolidometer to study the collapse behaviour. Initial water content, dry unit weight and flooding stress were varied. Collapse potential was found to be dependent on initial water content, initial dry unit weight and flooding stress. Partial collapse was studied by allowing measured increments of water into the specimens.  相似文献   
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The present work demonstrates the applicability of ferrites as photo‐Fenton catalysts for deterioration of different phenolic derivatives. To analyze optimal reaction conditions, experiments are performed with four magnetic spinel ferrites MFe2O4 (M = Co, Cu, Ni, and Zn) and two inorganic oxidants, i.e., hydrogen peroxide (HP) and potassium peroxymonosulfate (PMS). The reactions are performed using p‐nitrophenol as phenolic probe. CuFe2O4 and CoFe2O4 possessed excellent ability to activate HP and PMS, respectively, among all four synthesized catalysts. A noteworthy aspect of two oxidizing agents is that the concentration of PMS used during the reaction is four times less than HP. Further, the broad pH activity of PMS provides a significant advantage over HP. The optimal reaction conditions, when HP is the oxidant in the photo‐Fenton degradation, are 0.50 g L?1 MFe2O4, pH 2.5, and 8.8 mM HP. Although PMS is active in a wide pH range (2–10), adequate reaction conditions are 0.50 g L?1 MFe2O4, natural pH, and 2.2 mM PMS. The photo‐Fenton activity of ferrites is extended to the degradation of different nitro‐ and chloro‐analogs of phenol (2‐nitrophenol, 3‐nitrophenol, 4‐nitrophenol, 2,4‐dinitrophenol, 2,4,6‐trinitrophenol, 2‐chlorophenol, 3‐chlorophenol, 4‐chlorophenol, 2,4‐dichlorophenol) with only two ferrites (CuFe2O4 and CoFe2O4). A comparative study is performed with the two oxidants (HP and PMS) with positive results. Finally, stability and reusability of magnetic ferrites as catalysts are also studied to prove their use in phenolic solution treatment.  相似文献   
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Geochemical data are presented for primitive alkaline rocks from the Kutch region, north–northwest of Deccan Volcanic Province (DVP) of west central India, which is generally regarded as related to the Reunion Plume. The trace element systematics of these rocks are similar to those of ocean-island basalts, but there is considerable compositional variation, which is related to a strong overprint from the lithosphere on plume-derived magmas. This subcontinental lithospheric mantle (SCLM) component has geochemical characteristics that overlap those observed in spinel lherzolite xenoliths entrained in these rocks. Phlogopite and apatite in the SCLM are of metasomatic origin attributed to the infiltrating fluids and/or melts derived from rising mantle plume material. The composition of the alkaline rocks is consistent with a regional upwelling of deep mantle related to marginal rifting and with OIB-type geochemical characteristics. Thermal inhomogeneities within such plume swath resulted in small diapirs, which may have undergone melt segregation at the base of the lithosphere (100 km) and incorporated varying amounts of SCLM during ascent.  相似文献   
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The major oil and gas producing fields in Gujarat are found in Cambay basin. It is known that a huge amount of water is produced with oil and gas production which is called produced oilfield water. Some useful elements (iodine, lithium and strontium) are present with this oilfield water which may be extracted in case of their abundance. The investigation of iodine, lithium and strontium concentrations in produced oilfield water was accomplished by Ion chromatography while for other cations ICP instrument was used. In oilfield water, iodine content ranges from 0.08 to 1.89 mg/l, lithium content ranges from 0.06 to 2.90 mg/l and strontium content ranges from 0.24 to 73.5 mg/l. In addition to above element, Na, Mg, K, Ca, Al, Ba, Fe, Se, Cu, Zn, As, Cd and Hg were also analyzed. The pH and TDS of all the samples were also measured. There is considerable variation in iodine, lithium and strontium in oilfield water samples collected from oil and gas producing fields of Gujarat. There is no definite pattern of variation in iodine, lithium and strontium content.  相似文献   
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Middle Eocene Fulra Limestone and Oligocene Maniyara Fort Formation represent platform carbonate deposits of Kutch at the north-western margin of India. These carbonates contain larger benthic foraminifera, including Alveolina, Assilina, Discocyclina, Lepidocyclina, Miogypsina, Nummulites and Spiroclypeus. This study presents paleodepositional and paleobathymetric interpretations for both formations using benthic foraminifera in combination with lithological association, sedimentary structures and early diagenetic features. The six carbonate facies comprising the Fulra Limestone indicate a depositional spectrum ranging from bar-lagoon to mid-ramp depositional conditions. It records several shallowing upward cycles, leading to emergence and formation of paleokarst. The four carbonate facies of the Maniyara Fort Formation represents deposition within the inner ramp setting in bar-lagoon and patch-reef environment, while intervening fine siliciclastics correspond to episodes of relative sea level fall. Nummulitic accumulations form low-relief bars within the fair weather wave base in both the formations. The depositional setting of the Paleogene carbonate in Kutch broadly resembles Eocene platformal deposits in the circum-Tethys belt.  相似文献   
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