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The water vapor in the atmosphere is mainly formed through the vaporization of water from oceans, open land water sources, and transpiration through forests and agricultural crops. In the present study, our aim was to formulate a mathematical model to see the effect of transpiration from agricultural crops on rainfall. In the model formulation, it is assumed that clouds are formed in the atmosphere through the transpiration of agricultural crops proportional to the crops apart from the oceans and other sources (assumed constant). It is observed that in the presence of agriculture crops, the average rainfall increases. In the presence of clouds, cloud seeding techniques (use of conducive aerosols) are used to stimulate rainfall, which increases the agricultural crops with saturated type functional form. To capture the impact of environmental fluctuations, the stochastic version of the proposed model is also studied. The analysis of the model reveals that cloud seeding not only increases the rainfall, but it also increases the agricultural crops and clouds in the atmospheric environment. [ABSTRACT FROM AUTHOR]

negative carbon isotope excursion at Paleocene-Eocene boundary in Jaisalmer Basin has been recognized for the first time. Besides excursion at P-E transition, short but significant negative carbon isotope shift has also been observed preceding the Paleocene-Eocene thermal maximum (PETM). The study discusses the possible mechanism for PETM and pre-CIE warm conditions in Jaisalmer Basin, India. [ABSTRACT FROM AUTHOR]

57Fe Mössbauer Spectroscopy study was carried out on the samples collected from different depth interval of a representative well K-263 of the North Cambay basin (India). The results obtained were compared with the basins already studied. Comparison show that general trend of relative distribution of iron containing minerals as a function of depth for well K-263 is more or less similar to that reported for Eastern Krishna Godavari Basin. Interestingly both these basins have similar hydrocarbon prospecting (hence nature of organic content) also. On the other hand we found that distribution pattern of iron minerals of Cambay basin is markedly different from the basins (viz North Sea and Jaisalmer) having different prospecting and organic properties in comparison to Cambay Basin. So some correlation exists between distribution of iron minerals and prospects of a basin. [ABSTRACT FROM AUTHOR]

In nature, the mineral ‘Cubanite’ with composition CuFe2S3 occurs in orthorhombic structure in the matrix of chalcopyrite and pyrrhotite. Synthesis of this mineral in the laboratory conditions has not been reported yet. An attempt to synthesize the orthorhombic Cu–Fe–Sulfide (cubanite) by resistive as well as microwave heating technique is reported. MW-heated sample shows the presence of orthorhombic component along with isocubanite and pyrrhotite. The synthesized samples were studied in details through XRD and Mössbauer spectroscopy. The synthesis process, responsible for different proportions of the minerals, may indicate the conditions of their genesis in nature. Formation of isocubanite (cubic cubanite) seems unavoidable under the conditions of synthesis. The striking indistinguishable character of cubanite and chalcopyrite could be challenged through Mössbauer hyperfine parameter—the hyperfine field of chalcopyrite (~37 T) being quite different from that of cubanite (~33 T). [ABSTRACT FROM AUTHOR]

A sample of an ordinary chondrite fall, Didwana-Rajod, Rajasthan, India which was shown to be largely unweathered, was exposed to weathering in laboratory conditions. Wet and dry cycle of different strengths (0.01 and 0.1 M) of sodium sulfate solution was applied for different periods of time (maximum of 140 days). An attempt was made to simulate meteorite weathering more or less analogous to environmental exposure in desert-like conditions. It is found that lower concentration of the attacking ions is more effective in weathering the meteorite. Kamacite is affected in early cycles of weathering more than any other mineral. The olivine to pyroxene ratio is much less affected. [ABSTRACT FROM AUTHOR]

Mössbauer spectroscopic studies of two sedimentary layers from Petriccio section in Gubbio formation are presented. It is found that these layers have almost the same iron phases nanophase hematite and phyllosilicate and with the same compositions as those in the Cretaceous-Tertiary Boundary (KTB) in Petriccio. The two layers also show enhancement in the siderophile elements such as Cr, Ni, Fe, Ca etc. to that found in the KTB layer. The two layers are well separated from the KTB layer, 128 and 149 cm below this layer, and show no enhancement of iridium. From the data it is suggested that the two layers also represent some kind of impact by extraterrestrial (ET) bolides. [ABSTRACT FROM AUTHOR]