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Rishi Madhuri S. Keesari Tirumalesh Sharma Diana A. Pant Diksha Sinha Uday K. 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(3):1937-1945
A hydrochemical study was undertaken in uranium impacted districts of southwest Punjab for evaluating the spatial and vertical trends as well as correlations with other hydrochemical parameters. Results infer that U is present in all samples (12.2–621 µg l−1) and 90% are contaminated. Contour diagram depicts contamination in entire region excepting some pockets in central part of the study area. Shallow zones (<50 m bgl) show higher U compared to deeper ones. Hydrochemistry infers a common source of U for both shallow and deep zones and alkalinity as the governing factor for U mobilization from the sediments.
相似文献2.
Thakur Nandini Rishi Madhuri Keesari Tirumalesh Sharma Diana Anoubam Sinha Uday Kumar 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(3):1217-1225
Journal of Radioanalytical and Nuclear Chemistry - Environmental stable and radioisotope data of springs located in Kullu region of Himachal Pradesh are interpreted to identify the recharge source... 相似文献
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Prof. Dr. Sambasivarao Kotha Ramakrishna Reddy Keesari 《European journal of organic chemistry》2023,26(18):e202300106
Herein, a short synthetic approach to linearly fused tricyclic enone 1 and cis-anti-cis type hydroxy-triquinane 2 has been described in an efficient manner by employing tandem-metathesis as a key step. The triquinane-based enone 1 is prepared by a Babler–Dauben oxidation of hydroxy-triquinane 2 , which is assembled by following a three-step sequence involving a regio- and stereoselective allylation, vinyl Grignard addition, and tandem-metathesis. Our strategy relies on exo-tricyclic ketone, which is derived from readily available exo-dicyclopentadiene-1-one. The newly synthesized molecules were identified and characterized by nuclear magnetic resonance spectroscopy (NMR), and high-resolution mass spectrometry (HRMS) data. It is worth mentioning that tricyclic enone 1 is present as a core unit of many naturally occurring polyquinanes, particularly xeromphalinone family members. Hence, our approach may be useful in the synthesis of such bioactive molecules. 相似文献
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Pant Diksha Keesari Tirumalesh Roy A. Sinha U. K. Singh Manveer Jain S. K. Tripathi R. M. 《Journal of Radioanalytical and Nuclear Chemistry》2019,320(1):165-177
Journal of Radioanalytical and Nuclear Chemistry - Herein, a practical and simple reduction method was used to prepared the nanoscale composites of hydroxyapatite (HAP) coated with zero valent iron... 相似文献
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Tirumalesh Keesari Hemant V. Mohokar Bijay Kumar Sahoo G. Mallesh 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(3):1391-1398
The objective of this work was to determine the radioactive element concentrations in groundwater in parts of the Nalgonda district. Results indicate that 222Rn activity is present in significant levels in deep groundwater compared to shallow groundwater and tank water. An increasing 222Rn activity trend is noticed along the well depth while electrical conductivity, uranium, and alkalinity levels showed inverse trends. Environmental tritium data indicates modern recharge to groundwater. Inter-elemental correlations suggest that high dissolved uranium is associated with high alkalinity and high electrical conductivity groundwater. The study also infers recharge sources and mechanisms to shallow and deep groundwater. 相似文献
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Tirumalesh Keesari U. P. Kulkarni Ajay Jaryal G. N. Mendhekar K. N. Deshmukh A. G. Hegde S. N. Kamble 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(1):1-6
This paper presents application of a radiotracer technique in coastal groundwater for assessing the aquifer dynamics, which is very crucial for understanding flow conditions of an aquifer and its vulnerability to salinity and other contamination. Groundwater dynamics in shallow and deep zones of Palghar Taluk located in west coast of Thane district were studied using point dilution method. 82Br in the form of NH4Br solution was used as the radiotracer and loggings were carried out by NaI (Tl) scintillation detector. From the analysis of the radiotracer activity loggings, it is found that shallow groundwater is relatively dynamic as compared to deeper groundwater at the two studied sites. The groundwater velocity is about 40–50 cm/day in the shallow zone while it is in the range of 4–40 cm/day in the deep zone. High salinity in deeper parts could be due to seawater intrusion through fractured basalt, which is diluted/flushed in the shallow zone by rain and river water. These findings are helpful in assessing groundwater dynamics in shallow and deep zones of this region and also on the impact of pumping activity on groundwater dynamics. 相似文献
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Prof. Dr. Sambasivarao Kotha Ramakrishna Reddy Keesari Dr. Ongolu Ravikumar 《European journal of organic chemistry》2023,26(9):e202201448
Here, we report a new synthetic approach to a highly strained 1,3-fused cis-cis-cis-5/5/6 tricyclic system that appeared among the presilphiperfolanol analogues. The cis-fusion of six-membered ring to a diquinane moiety is accomplished by substrate-controlled regio- and stereoselective epoxidation, and ring-rearrangement metathesis (RRM) sequence. In this regard, both early-, and late-stage epoxidation and RRM reactions were studied. The target compound, cis-cis-cis-5/5/6 tricyclic ketone with an α,β-oxirane ring can serve as a key building block to produce various presilphiperfolanol analogues. The cis-cis-cis-5/5/6-tricyclic-α,β-epoxyketone can also act as masked enone and therefore useful for various chemical transformations in organic synthesis. The short synthetic sequence disclosed here may be useful to design various biologically important molecules. The newly reported molecules are well-characterized by NMR, HRMS, and IR spectral data. 相似文献
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Sharma Diana Anoubam Keesari Tirumalesh Rishi Madhuri Thakur Nandini Pant Diksha Mohokar Hemant Vasant Jaryal Ajay Kamble Suryakant Namdeo Sinha Uday Kumar 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(3):1257-1267
Journal of Radioanalytical and Nuclear Chemistry - A study was undertaken to measure the dissolved radon (222Rn) concentration in parts of western India (Southwest Punjab) in order to evaluate its... 相似文献
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Keesari Tirumalesh Chatterjee Sitangshu Pant Diksha Kumar Mukund Sakhare Vishal Sinha Uday Kumar Mohokar Hemant Jaryal Ajay Roy Annadasankar Maitra Asmita 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(3):1227-1235
Journal of Radioanalytical and Nuclear Chemistry - In this study environmental radioisotopes of water (3H and 14C) were used to determine the residence time of thermal waters. The temperature of... 相似文献
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Diana A. Sharma Madhuri S. Rishi Tirumalesh Keesari Diksha Pant Rakhi Singh Nandini Thakur Uday K. Sinha 《Journal of Radioanalytical and Nuclear Chemistry》2017,313(3):625-633
This paper presents the isotope hydrochemical results of groundwaters from southwest Punjab for assessing the uranium contamination and evaluating the factors leading to elevated uranium concentration. A total of 35 samples covering shallow and deep zones were collected for hydrochemistry and isotopes. Uranium concentration ranges between 2.3 and 357 µg L?1 and 66% of the samples are contaminated. Both shallow and deep zones show U contamination but high incidences are noticed in shallow zone. Hydrochemical correlations infer geological sources rather than anthropogenic sources responsible for U contamination. Isotopically there is no clear distinction between high and low U groundwater. 相似文献
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