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Das Pritam Kumar Mallik Arnab Kumar Molla Altaf Hossain Santra Apurba Kumar Ganguly Ranjan Saha Abhijit Kumar Sugam Aswal V. K. 《Journal of Thermal Analysis and Calorimetry》2022,147(10):5617-5635
Journal of Thermal Analysis and Calorimetry - Nanofluids have gained recent attention because of their potential applications in diverse engineering fields like enhancing thermal transport,... 相似文献
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We quantify the long-time behavior of solutions to the nonlinear Boltzmann equation for spatially uniform freely cooling inelastic Maxwell molecules by means of the contraction property of a suitable metric in the set of probability measures. Existence, uniqueness, and precise estimates of overpopulated high energy tails of the self-similar profile proved in ref. 9 are revisited and derived from this new Liapunov functional. For general initial conditions the solutions of the Boltzmann equation are then proved to converge with computable rate as t → ∞ to the self-similar solution in this distance, which metrizes the weak convergence of measures. Moreover, we can relate this Fourier distance to the Euclidean Wasserstein distance or Tanaka functional proving also its exponential convergence towards the homogeneous cooling states. The findings are relevant in the understanding of the conjecture formulated by Ernst and Brito in refs. 15, 16, and complement and improve recent studies on the same problem of Bobylev and Cercignani(9) and Bobylev, Cercignani and one of the authors.(11) 相似文献
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Ahlen S Ambrosio M Antolini R Auriemma G Baker R Baldini A Bam BB Barbarino GC Barish BC Battistoni G Bellotti R Bemporad C Bernandini P Bilokon H Bisi V Bloise C Bower C Bussino S Cafagna F Calicchio M Campana D Campana P Carboni M Cecchini S Cei F Chiarella V Cormack R Corona A Coutu S De Cataldo G Dekhissi H De Marzo C De Vincenzi M Di Credico A Diehl E Erriquez O Favuzzi C Ficenec D Forti C Fusco P Giacomelli G Giannini G Giglietto N Giubellino P Grassi M Green P Grillo A Guarino F 《Physical review letters》1994,72(5):608-612
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Multi-ligand self-assembly to attain the AgI-N-heterocyclic carbene (NHC)-built hexanuclear organometallic cages of composition [Ag6( 3 a , b )4](PF6)6 from the reaction of benzimidazole-derived tris(azolium) salts [H3- 3 a , b ](PF6)3 with Ag2O was achieved. The molecular structures of the cages were established by X-ray diffraction studies along with NMR and MS analyses. The existence of a single assembly in solution was supported by diffusion-ordered spectroscopy (DOSY) 1H NMR spectra. Further, transmetalation reactions of these self-assembled complexes, [Ag6( 3 a , b )4](PF6)6, with CuI/AuI-ions provided various coinage metal-NHC complexes having diverse molecular compositions, which included the first example of a hexanuclear CuI-dodecacarbene complex, [Cu6( 3 b )4](PF6)6. 相似文献
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Arnab Chatterjee Satyanshu Kumar Sunil K. Chattopadhyay 《Biomedical chromatography : BMC》2013,27(12):1720-1725
A simple, rapid, accurate and reproducible reverse‐phase HPLC method has been developed for the identification and quantification of two alkaloids ephedrine and cryptolepine in different extracts of Sida species using photodiode array detection. Baseline separation of the two alkaloids was achieved on a Waters RP‐18 X‐terra column (250 × 4.6 mm, 5 µm) using a solvent system consisting of a mixture of water containing 0.1% Trifluoroacetic acid (TFA) and acetonitrile in a gradient elution mode with detection at 210 and 280 nm for ephedrine and cryptolepine, respectively. The calibration curves were linear in a concentration range of 10–250 µg/mL for both the alkaloids with correlation coefficient values >0.99. The limits of detection and quantification for ephedrine and cryptolepine were 5 and 10 µg/mL and 2.5 and 5 µg/mL, respectively. Relative standard deviation values for intra‐day and inter‐day precision were 1.22 and 1.04% for ephedrine and 1.71 and 2.06% for cryptolepine, respectively. Analytical recovery ranged from 92.46 to 103.95%. The developed HPLC method was applied to identify and quantify ephedrine and cryptolepine in different extracts of Sida species. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Calixarenes are known to form host–guest complexes and supramolecular nanoassemblies with well-defined architectures. However, the use of these materials in conjunction with drug moieties is still under explored. One reason is the insufficient biocompatibility studies. Our present study represents a systematic in vitro investigation of the cytotoxicity associated with C-methylresorcin[4]arene, C-methylpyrogallol[4]arene, p-phosphonated calix[8]arene and a metal-seamed calixarene–copper(II) complex, using human HEK293 and rat C6G cell lines and two different cell viability assays (MTT and CellTiter-Glo) to avoid species-biased results. All compounds showed low to moderate toxicity. The trend in the CC50 values indicated that the suppression of the coordination ability and the presence of phosphonate groups decrease the overall cytotoxicity of the compounds. The results of this study not only establish calixarenes and their immediate families as potential drug carriers and drug modifiers, but also reveal a pathway for fine-tuning their toxicological behaviour by appropriate chemical modification. 相似文献