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Journal of Algebraic Combinatorics - The symbolic powers, in general, are not equal to the ordinary powers. Therefore, one interesting question here is for what classes of ideals ordinary and... 相似文献
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Rahul S. Patil Dr. Debasis Banerjee Cory M. Simon Prof. Jerry L. Atwood Dr. Praveen K. Thallapally 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(36):12618-12623
Separation of xenon and krypton is of industrial and environmental concern; the existing technologies use cryogenic distillation. Thus, a cost‐effective, alternative technology for the separation of Xe and Kr and their capture from air is of significant importance. Herein, we report the selective Xe uptake in a crystalline porous organic oligomeric molecule, noria, and its structural analogue, PgC‐noria, under ambient conditions. The selectivity of noria towards Xe arises from its tailored pore size and small cavities, which allows a directed non‐bonding interaction of Xe atoms with a large number of carbon atoms of the noria molecular wheel in a confined space. 相似文献
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Superperiodicity, chaos and coexisting orbits of ion-acoustic waves (IAWs) are studied in a multi-component plasma consisting of fluid ions, q -nonextensive cold and hot electrons and Maxwellian hot positrons. The significant impacts of the system parameters on superperiodic and nonlinear periodic IAWs are presented. Considering an external periodic perturbation various types of quasiperiodic and chaotic features for IAWs are studied in different parametric ranges through time series’ plots, phase spaces and Lyapunov exponents. It has been observed that there exist some coexisting orbits for IAWs. Coexisting orbits for IAWs in a classical electron–positron–ion plasma system are reported. 相似文献
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Molecular Diversity - Quantitative structure–activity relationship (QSAR) and read-across techniques have recently been merged into a new emerging field of read-across... 相似文献
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Dey Chaudhuri S. Banerjee D. Bhattacharjee T. Wasim Raja Sk Acharya R. Pujari P. K. 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(2):829-835
Journal of Radioanalytical and Nuclear Chemistry - Performance of 1″?×?1″ LaBr3 (5% Ce) scintillator coupled to Hamamatsu R2083 PM Tube has been investigated for the... 相似文献
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Johannes Maschita Dr. Tanmay Banerjee Gökcen Savasci Dr. Frederik Haase Prof. Christian Ochsenfeld Prof. Bettina V. Lotsch 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(36):15880-15888
Covalent organic frameworks (COFs) are an extensively studied class of porous materials, which distinguish themselves from other porous polymers in their crystallinity and high degree of modularity, enabling a wide range of applications. COFs are most commonly synthesized solvothermally, which is often a time-consuming process and restricted to well-soluble precursor molecules. Synthesis of polyimide-linked COFs (PI-COFs) is further complicated by the poor reversibility of the ring-closing reaction under solvothermal conditions. Herein, we report the ionothermal synthesis of crystalline and porous PI-COFs in zinc chloride and eutectic salt mixtures. This synthesis does not require soluble precursors and the reaction time is significantly reduced as compared to standard solvothermal synthesis methods. In addition to applying the synthesis to previously reported imide COFs, a new perylene-based COF was also synthesized, which could not be obtained by the classical solvothermal route. In situ high-temperature XRPD analysis hints to the formation of precursor–salt adducts as crystalline intermediates, which then react with each other to form the COF. 相似文献
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This study encompasses the synthesis and characterization of organotin(IV) derivatives of non-steroidal anti-inflammatory drug ibuprofen (IBF), viz. [(Me3Sn)(IBF)] ( 1 ), [(Bu3Sn)(IBF)] ( 2 ), [Ph3Sn(IBF)] ( 3 ), {[Me2Sn(IBF)]2O}2 ( 4 ) and [Bu2Sn(IBF)2] ( 5 ). The crystal structure of complex 3 , [Ph3Sn(IBF)], indicates a highly distorted tetrahedral (td) geometry with anisobidentate mode of coordination of the carboxylate group with tin atom, and a similar structure has been proposed for other two triorganotin(IV) derivatives. Moreover, the DFT (density functional theory) calculation and other studies have verified a dimer distannoxane type of structure for complex 4 , {[Me2Sn(IBF)]2O}2. Complex 5 has been found to exhibit a highly distorted octahedral geometry around the tin atom. To investigate the DNA binding profile of the synthesized complexes, viscosity measurement, UV–vis and fluorescence titrations were performed, which revealed an intercalative type of binding with DNA for IBF and complex 5 and external binding in case of the complexes 1 and 2 ; complexes 3 and 4 could not be studied owing to their insufficient solubility in tris buffer. Plasmid DNA fragmentation studies of IBF and complexes 1 , 2 and 5 indicate that they cleaved the pBR322 plasmid potentially. Further, the drugs IBF {2-[4-(2-methylpropyl)phenyl]propanoic acid}, MESNA (sodium 2-mercaptoethane-sulfonate), warfarin [2H-1-benzopyran-2-one,4-hydroxy-3-(3-oxo-1-phenylbutyl)], sulindac (2-{5-fluoro-1-[(4-methanesulfinylphenyl) methylidene]-2-methyl-1H-inden-3-yl}acetic acid) and their corresponding organotin(IV) complexes 1–19 (complexes 6–19 were synthesized/reported previously) were screened in vitro for cytotoxicity against human cancer cell lines viz. DU145 (prostate cancer), HCT-15 (colon adenocarcinoma), Caco-2 (colorectal adenocarcinoma), MCF-7 (mammary cancer), LNCaP (androgen-sensitive prostate adenocarcinoma) and HeLa (cervical cancer), through MTT reduction assay and the cause of cell death was investigated through acridine orange/ethidium bromide staining of cells and DNA fragmentation assay. The probable structure–cytotoxicity relationship is also discussed. The major role of apoptosis along with small necrosis was also validated by flow cytometry assay using annexin V–fluorescein isothiocyanate and propidium iodide analysis. 相似文献