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排序方式: 共有192条查询结果,搜索用时 296 毫秒
1.
Radhakrishnan M. Packianathan C. Sankaran B. Kandavelu P. Rosen B. P. 《Crystallography Reports》2021,66(7):1311-1315
Crystallography Reports - Exposure to environmental arsenic is associated with serious of health issues such as cancer, diabetes and developmental delays in infants and children. In human liver,... 相似文献
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Ponnusamy Kanchana Venkatesan Hemapriya Natarajan Arunadevi Sankaran Shanmuga Sundari Ill-Min Chung Mayakrishnan Prabakaran 《印度化学会志》2022,99(10):100679
Green synthesis of nanoparticles by eco-friendly methods is a recent technique which draws the attention of researchers because of the reward over many conventional chemical methods. The present work focuses on aqueous Limonia acidissima leaf extract in synthesizing silver nanoparticles and its applications in a simple way. The silver nanoparticles formed were characterized by Infrared, Ultra violet-visible, X-ray diffraction, transmission electron microscopic, and atomic force microscopic techniques. The powder X-ray diffraction studies and transmission electron microscopic images reveal that the silver nanoparticles synthesized were approximately 10–40 nm and have a spherical structure. The nanoparticles were assayed for their antibacterial, antifungal and antioxidant activity. The antimicrobial studies for the silver nanoparticles show a maximum zone of inhibition of 8.8 mm for Bacillus subtilis bacteria and 8.5 mm for Candida albicans fungi at 3 and 1 μg/mL respectively. In-silico ADMET studies reveal that the toxicity, bioactivity, pharmacokinetics and drug-likeness properties of Limonia acidissima leaf extract is good. The molecular docking studies show that the microbial activity is high for Bacillus subtilis and Candida albicans showing the coincidence of the in silico and in vitro studies as expected. The free radical scavenging activity of nanoparticles is 80 for 100 μg/mL. The 50% of inhibition of silver nanoparticles against human breast cancer cell lines is 18 μg/mL. It is evident that silver nanoparticles would be helpful in treating cancer cell lines and have great perspectives in the biomedical sector. 相似文献
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J.D. Eshelby (1957, 1959) has calculated the deformation field associated with an ellipsoidal inclusion in a state of homogeneous strain within an infinite matrix. Since most real precipitates occur with facets, the strain within such an inclusion is not uniform. Thus, plate precipitates of θ′ in Al-Cu and η in Al-Au have coherent broad faces with mismatches of 1.34 and 4.95 % respect- ively and semicoherent or disordered interfaces at the edges with residual mismatches of about ?4.3 and ?1.00% normal to the broad faces. The deformation field in the matrix around such precipitates has been calculated using Kelvin's (1848) result for the stress field due to a point force. The calculations show the existence of high stresses near the edges of the precipitates where they have an appreciable misfit. Unlike the case of an ellipsoidal inclusion, the stress fields of these precipitates have dilatational components which can affect the diffusion of solute atoms to them and, thus, the kinetics of interface migration. The behavior of alloys containing these precipitates indicates that the moduli of the precipitates are somewhat greater than those of the matrices. The present calculations, based on the assumption that the two moduli are the same, underestimate the actual deformation field in the matrix. In real systems, therefore, the effects of the deformation field on misfit dislocation nucleation and kinetics of interface migration are likely to be somewhat greater in general. 相似文献
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Chandraprakash Kumarasamy Amsaveni Sundarasamy Sankaran Mathan Uvarani Chokkalingam Ata Athar Mohan Palathurai Subramaniam Suresh Thangaraj 《Journal of heterocyclic chemistry》2019,56(11):2986-2992
A one‐pot, multicomponent, convergent microwave synthesis of some new pyranyl‐ and chromenyl‐substituted quinolines has been reported. Twenty compounds were prepared by the reaction of 2‐methoxy‐3‐formyl quinoline ( 1a‐d ), malononitrile ( 2 ), and kojic acid ( 4a‐d )/1,3‐cyclohexadione or dimedone ( 6a ‐ h )/α‐ or β‐naphthol ( 8a ‐ d , 8e ‐ h ). The structures were confirmed by infrared (IR), 1H nuclear magnetic resonance (NMR), 13C NMR, mass, and single‐crystal X‐ray analyses. On comparison with the use of conventional Lewis acid catalysts and various metal triflates under microwave conditions, the latter contributed to good yields, in specific use of the recyclable Yb(OTf)3 catalyst attributed to high yields of the desired product. The protocol reported herein is solvent free, cost effective, and eco‐friendly. 相似文献
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S. Maji Satendra Kumar K. Sankaran 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(3):1277-1281
A fluorescence based method has been developed for the determination of trace amounts of uranium in thorium matrix using a mixture of phosphoric acid (H3PO4) and sulfuric acid (H2SO4), as fluorescence enhancing reagent for uranyl (UO2 2+) ion fluorescence. Synthetic samples mimicking the composition of ThO2 fuel were prepared and the concentration of U(VI) was estimated. Satisfactory results are obtained when uranium is present at a concentration of 10 ppm in solid thorium samples with good precision. 相似文献
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K. Jeevarenuka G. Sankaran Pillai P. Shahul Hameed R. Mathiyarasu 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(1):245-252
The activity concentrations and absorbed gamma dose of primordial radionuclides 238U, 232Th and 40K were determined employing γ-ray spectrometry in 31 soil samples from the land area earmarked for house construction in Perambalur district and 14 rock samples from quarries that supply stones for the entire district. The soil samples registered relatively a higher mean value of 13.2 Bq kg?1 for 238U, 66 Bq kg?1 for 232Th and 340.3 Bq kg?1 for 40K as compared to mean values for rock samples (238U—8.0 Bq kg?1; 232Th—65.1 Bq kg?1; 40K—199.1 Bq kg?1). The mean absorbed gamma dose rate for soil (61.4 nGy h?1) marginally exceeded the prescribed limit of 55 nGy h?1 while, rocks registered the mean absorbed gamma dose rate of 10.4 nGy h?1. The mean radium equivalent activity was distinctly higher in soil (130.6 Bq kg?1) than in rock (20.0 Bq kg?1). However, these values were lower than the limit (370 Bq kg?1) set by OECD for building materials. It is evident from the data that the soil and rocks do not pose any radiological risk for house constructions in Perambalur district. 相似文献
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A. Stephen K. Hashmi Prof. Dr. Christian Lothschütz Dipl.‐Chem. Martin Ackermann Dipl.‐Chem. René Doepp Dipl.‐Chem. Sankaran Anantharaman Benjamin Marchetti Dipl.‐Chem. Helmut Bertagnolli Prof. Dr. Frank Rominger Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(27):8012-8019
Gold complexes were prepared and investigated as catalysts for the oxidative esterification of aldehydes. Stabilisation by pyridine ligands gave good conversions and the in situ extended X‐ray absorption fine structure (EXAFS) study of the reactions indicated that the reaction mixtures contained only mononuclear gold species. Thus, this is the first proof for a homogeneous gold‐catalysed oxidation reaction; the presence of nanoparticles could be excluded experimentally. 相似文献
10.
S.J. Kamkar A.M. Wissink V. Sankaran A. Jameson 《Journal of computational physics》2011,230(16):6271-6298
We develop locally normalized feature-detection methods to guide the adaptive mesh refinement (AMR) process for Cartesian grid systems to improve the resolution of vortical features in aerodynamic wakes. The methods include: the Q-criterion [1], the λ2 method [2], the λci method [3], and the λ+ method [4]. Specific attention is given to automate the feature identification process by applying a local normalization based upon the shear-strain rate so that they can be applied to a wide range of flow-fields without the need for user intervention. To validate the methods, we assess tagging efficiency and accuracy using a series of static vortex-dominated flow-fields, and use the methods to drive the AMR process for several theoretical and practical simulations. We demonstrate that the adaptive solutions provide comparable accuracy to solutions obtained on uniformly refined meshes at a fraction of the computational cost. Overall, the normalized feature detection methods are shown to be effective in driving the AMR process in an automated and efficient manner. 相似文献