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21.
Photodissociation of styrene oxide at 193 nm in gas phase generates OH, as detected by laser-induced fluorescence technique. Under similar conditions, OH was not observed from ethylene and propylene oxides, primarily because of their low absorption cross-sections at 193 nm. Mechanism of OH formation involves first opening of the three-membered ring from the ground electronic state via cleavage of either of two CO bonds, followed by isomerization to enolic forms of phenylacetaldehyde and acetophenone, and finally scission of the COH bond of enols. Ab initio molecular orbital calculations support the proposed mechanism.  相似文献   
22.
Journal of Radioanalytical and Nuclear Chemistry - Individual separation of rare earth isotopes from lanthanum to lutetium has been carried out using reverse phase partition chromatography and...  相似文献   
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Journal of Radioanalytical and Nuclear Chemistry - We measured excitation functions for the production of the 108m,108g,109g,110m,110g,111gIn, the 109g,111mCd, and the 105g,106m,110m,111gAg in...  相似文献   
24.
Pursuing our recent interest regarding antimicrobial and anti-inflammatory activities of coumarin derivatives, we have synthesized a series of coumarin-linked pyridopyrimidinones by using Baylis Hillman adduct in aqueous condition with high purity. Pyrido[1,2-a]pyrimidin-2-ones are important class of heterocyclic compounds because of their use in medicinal and agro chemistry as active agents. All these newly synthesized compounds were evaluated for their antimicrobial and anti-inflammatory activity. Coumarin pyridopyrimidinones showed excellent anti-inflammatory activity against both MMP-2 and MMP-9 gelatinase zymography, whereas considerable good activity against Gram-positive and Gram-negative bacterial strains; however, antifungal activity observed in these series is more or less inactive. The active compounds of these series would be promising structural templates for the development of novel and more efficient anti-inflammatory agent.  相似文献   
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Ramesh Naik 《合成通讯》2013,43(10):1723-1726
Dimethylsulfoxide (DMSO) oxidizes benzyl ethers into corresponding benzaldehydes at 110°C; the reaction is accelerated by 49% aq. HBr. The conditions work well for different aryl‐substituted benzyl ethers. This protocol is inert toward dialkyl ethers.  相似文献   
27.
The production cross-section of the medical isotope, 99Mo from the enriched 100Mo(n,2n) reaction with the average neutron energies of 21.9 and 26.5 MeV has been determined for the first time by using an off-line γ-ray spectrometric technique. The average neutron energies were generated by using the 9Be(p,n) reaction with the proton energies of 35 and 45 MeV from the MC50 cyclotron of the Korea Institute of Radiological and Medical Sciences (KIRAMS) at Seoul, South Korea. The 100Mo(n,2n) reaction cross-section as a function of neutron energy was also calculated theoretically by using the computer code TALYS-1.8 and EMPIRE-3.2 Malta. The experimental results are in close agreement with the theoretical values from TALYS-1.8. However, the present data at the neutron energy of 21.9 MeV is slightly lower and at 26.5 MeV is higher than the values from EMPIRE-3.2 Malta.  相似文献   
28.
Mononuclear divalent complexes of Co, Ni, Cu and Zn derived from a benzofuran‐based novel hydrazone tridentate ligand were synthesized and characterized using various spectroscopic methods. Elemental analysis reveals that the metal‐to‐ligand ratio is 1:2 which is supported by mass spectrometry results. Conductivity measurements suggest that all the complexes are non‐electrolytic in nature. The ligand and complexes were evaluated for their antimicrobial potency. Bioassay of all hydrazone chelates shows enhanced activity as compared to that of the ligand. The complex with cobalt ion as the metal centre shows better activity against fungi than the standard. Also, ligand and complexes were screened for antituberculosis activity; some analogues (Ni, Cu, Zn) are eight times more active than the standard. Both ligand and complexes show moderate ability to cleave calf thymus DNA. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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This article reviews static and dynamic models of information aggregation in the literature. It highlights the key assumptions these models make, the results they obtain and the issues that still need to be explored to further our understanding of information aggregation in financial markets.  相似文献   
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