U–Pb geochronology,Sr–Nd isotopic compositions,geochemistry and petrogenesis of Shah Soltan Ali granitoids,Birjand, Eastern Iran     

Mohammad Hassan Karimpour  Azadeh Malekzadeh Shafaroudi  José Francisco Santos  Ryan Mathur  Sara Ribeiro 《Chemie der Erde / Geochemistry》2018,78(3):299-313

The Shah Soltan Ali area (SSA) is located in the eastern part of the Lut Block metallogenic province. In this area different types of sub-volcanic intrusions including diorite porphyry, monzonite porphyry and monzodiorite porphyry have intruded into basaltic and andesitic rocks. Zircon U–Pb dating and field observations indicate that intermediate to mafic volcanic rocks (38.9 Ma) are older than subvolcanic units (38.3 Ma). The subvolcanic intrusions show high-K calc-alkaline to shoshonitic affinity and are metaluminous. Based on mineralogy, high values of magnetic susceptibility [(634 to 3208) × 10^?5 SI], and low initial ⁸⁷Sr/⁸⁶Sr ratios, they are classified as belonging to the magnetite-series of oxidant I-type granitoids and are characterized by an enrichment in LREEs relative to HREEs, with negative Nb, Ti, Zr and Eu anomalies. These granitoids are related to volcanic arc (VAG) and were generated in an active continental margin. Low initial ⁸⁷Sr/⁸⁶Sr ratios (0.7043 to 0.7052) and positive εNd values (+1.48 to +3.82) indicate that the parental magma was derived from mantle wedge. Parental magma was probably formed by low degree of partial melting and metasomatized by slab derived fluids. Then assimilation and fractional crystallization processes (AFC) produced the SSA rocks. This magma during the ascent was contaminated with the crustal material.All data suggest that Middle-Late Eocene epoch magmatism in the SSA area, occurred during subduction of Neo-Tethys Ocean in east of Iran (between Afghan and Lut Blocks).  相似文献   

Feasibility study of waste (d) potential: co-digestion of organic wastes,synergistic effect and kinetics of biogas production     

K. Paritosh  S. Mathur  N. Pareek  V. Vivekanand 《International Journal of Environmental Science and Technology》2018,15(5):1009-1018

The present study investigated the synergistic effect of co-digesting food and green waste from institute campus for enhanced biogas production in different ratios in batch tests (37 ± 1 °C, 90 rpm, 45 days). The results showed that blending improved the biogas production significantly, with highest biogas yield (660 ± 24 mL g^?1 volatile solids) that was achieved at 75:25 of food and green waste ratio on volatile solids basis. The yield was 1.7- and 1.9-fold higher than the mono-digestion of food and green waste (370 ± 34; 342 ± 36 mL g^?1 volatile solids), respectively. The increase in biogas production may be attributed to optimum carbon to nitrogen ratio resulting in higher yield. The addition of TiO₂ nanoparticles showed virtually no effect on biogas production. Characterization was carried out to gain an insight of feedstocks. Modified Gompertz and logistics models were applied for kinetic study of biogas production where modified Gompertz model showed goodness of fit (R ² = 0.9978) with the experimental results.  相似文献   

Mo isotope fractionation during hydrothermal evolution of porphyry Cu systems   总被引：3，自引：0，他引：3  

Behnam Shafiei  GholamHossein Shamanian  Ryan Mathur  Hassan Mirnejad 《Mineralium Deposita》2015,50(3):281-291

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Mobile livelihoods among ethnic minorities in China: Insights from Yunnan     

Yunxian Wang  Kyoko Kusakabe  Ragnhild Lund  Smita Mishra Panda  Qun Zhao 《Norsk geografisk tidsskrift. Norwegian journal of geography》2013,67(4):187-199

Ethnic minority populations in Yunnan have had diverse mobility patterns since the advent of globalized production and developmental programmes. The article presents insights into the various mobility patterns and their effects in Yunnan and contributes to an understanding of the present economic and social processes of mobilities and changes in China as a whole. The analysis is based on an empirical study conducted in the years 2010–2011 by the authors together with local researchers in Yunnan. The results revealed that the mobilities practised among members of the ethnic minority groups in Yunnan included not only outmigration but also cross-border cultivation of plantations, daily and circular mobility, inflows of labour and investors, and involuntary relocation. Although some mobilities may have been conducive to livelihoods and capabilities due to the income-earning and profit-making opportunities arising from the acquisition and appropriation of land and capital, they have also resulted in differentiation processes that confirm the counter-geographies of production, survival, and profit-making. The authors conclude that mobilities do not just concern physical location, but as a social process, mobilities have reconstituted relational references and networks in terms of ethnic and cultural identity, gender relations, labour division, and locality and community integration.  相似文献   

Biotransformation of amide using Bacillus sp.: isolation strategy, strain characteristics and enzyme immobilization     

M. Sogani  N. Mathur  P. Bhatnagar  P. Sharma 《International Journal of Environmental Science and Technology》2012,9(1):119-127

Amidase hydrolases/acyltransferases are of considerable industrial interest due to potential applications in the production of useful hydroxamic acids. The test strain, capable of acetamide degradation, was isolated by an enrichment technique with acetamide as sole source of nitrogen. Based on morphology, physiological tests and biochemical tests, this isolate was identified as Bacillus sp. and on the basis of 16S Ribosomal ribonucleic acid sequence, a phylogenetic tree was drawn and was identified as Bacillus megaterium. Resting cells containing active acyltransferase enzyme were prepared and immobilized in the gel beads of sodium alginate, agar, polyacrylamide and polyvinyl alcohol?Calginate. The beads were tested for acyltransferase using Iron (III) chloride reagents at 55°C and were found to be affected by substrate concentration, type of buffer, buffer pH and reaction temperature. These factors were optimized using sodium alginate immobilized beads. This study proved useful in understanding the technique of immobilization of acyltransferase enzyme, its operational stability and its importance in the synthesis of hydroxamic acid.  相似文献   

Geomagnetic field variation during winter storm at localized southern and northern high latitude     

Babita Devi  Smita Dubey  Shailendra Saini  Rajni Devi  Rashmi Wahi  Ajay Dhar  S. K. Vijay  A. K. Gwal 《Journal of Astrophysics and Astronomy》2008,29(1-2):275-280

This paper presents the effect of geomagnetic storm on geomagnetic field components at Southern (Maitri) and Northern (Kiruna) Hemispheres. The Indian Antarctic Station Maitri is located at geom. long. 66.03° S; 53.21° E whereas Kiruna is located at geom. long. 67.52° N; 23.38° E. We have studied all the geomagnetic storms that occurred during winter season of the year 2004–2005. We observed that at Southern Hemisphere the variation is large as compared to the Northern Hemisphere. Geomagnetic field components vary when the interplanetary magnetic field is oriented in southward direction. Geomagnetic field components vary in the main phase of the ring current. Due to southward orientation of vertical component of IMF reconnection takes place all across the dayside that transports plasma and magnetic flux which create the geomagnetic field variation.  相似文献   

Effect of interplanetary magnetic field and disturb storm time on H component     

Rajni Devi  Smita Dubey  Shailendra Saini  Babita Devi  Ajay Dhar  S. K. Vijay  A. K. Gwal 《Journal of Astrophysics and Astronomy》2008,29(1-2):281-286

A fluxgate digital magnetometer is used to study the variation of magnitude of H component during geomagnetic storm events of April, July and November 2004 at southern subauroral localized region at “MAITRI” (geom. lat. 62°S, long. 52.8°E). We also study the effect of vertical component of interplanetary magnetic field (IMF) on the variation of the magnitude of H component during storm time of April, July and November 2004. Results show that before sudden storm commencement (SSC) time magnitude of H component and IMF show smooth variation but after SSC of first storm of 22 July 2004, the magnitude of the H component shows fluctuations and at 09:00 UT it increases, but during second storm of 24 July 2004, the magnitude of H component indicates large fluctuations and it increases rapidly at 04:00 UT.  相似文献   

Discovery of animal eggs and embryos from the Ediacaran (Terminal Proterozoic) Chambaghat Formation,Krol Group,Himachal Lesser Himalaya     

V. K. Mathur  V. P. Mishra  Shambhu Nath 《Journal of the Geological Society of India》2009,74(4):498-502

The globular to suboval microfossils with distinctively ornamented outer coverings interpreted as animal eggs and embryos have been discovered from the black phosphatic chert lentils of the Ediacaran (Terminal Proterozoic) Chambaghat Formation (Krol sandstone), Krol Group, Himachal Lesser Himalaya, India. Similar animal eggs and embryos have earlier been recorded only from the phosphorites of the uppermost Neoproterozoic Doushantuo Formation (Ca. 570±20 Ma) exposed at Weng’an, South China. Present record of eggs and embryos is comparable with extant eggs and embryos of cnidarians and bilaterians like molluscs, annelids and arthropods. The eggs and embryos from the Terminal Proterozoic rocks of India are the only one recorded from the equivalent stratigraphic horizon outside China. This discovery of eggs and embryos adds to the understanding the evolutionary trends in the Proterozoic metazoan life.  相似文献   

Hydrochemical characterization and suitability assessment of groundwater in Baga–Calangute stretch of Goa,India     

A. K. Haritash  Karamveer Mathur  Priyanka Singh  S. K. Singh 《Environmental Earth Sciences》2017,76(9):341

The present study is the first attempt to determine the suitability of groundwater for drinking and irrigation in the Baga–Calangute stretch of Goa. The suitability of groundwater for potable use was assessed by comparing observed values against standards prescribed by the Bureau of Indian Standards, and the quality was classified based on the Weighted Arithmetic Water Quality Index. Most of the groundwater samples (90%) were found to be suitable for drinking except for hardness, chlorides, and nitrates. The percent sodium (%Na), residual sodium carbonate, soluble sodium percentage, sodium adsorption ratio, Kelly’s ratio, and Permeability Index were found to be within the prescribed limits for irrigation purposes. The major mechanism controlling groundwater chemistry, i.e., rock–water interaction, was also studied, and it was found that silicate weathering plays a major role in the dissolution of minerals. Based on the hydrochemical characterization, the water was observed to be of the Ca–Na–SO₄ composition type except for one sample which was of the Na–Cl composition type. Classification of the meteoric genesis suggested that the groundwater in surficial aquifers in the region had a deep meteoric percolation, and its chemistry is regulated by rock–water interaction.  相似文献   

The Raghunathpura iron meteorite from Alwar,India     

V. S. Bapna  P. N. Sharma  M. D. Sathe  K. N. Mathur  G. L. Dwivedi 《Meteoritics & planetary science》1991,26(1):65-67

Abstract— The Raghunathpura iron meteorite fell on 20 November 1986 around 8 p.m.; it weighed 10.2 kg. It is a group IIA hexahedrite based on metallographic, x-ray diffraction and chemical studies. Eighteen major, minor and trace elements were determined using classical, atomic-absorption spectrometry and semiquantitative spectrographic procedures.  相似文献