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71.
The title compound, C20H19NO2S2, is formed by a palladium–copper‐catalyzed reaction between 4‐methyl‐N‐[2‐(prop‐2‐ynyl­sul­fanyl)­phenyl]­benzene­sul­fon­amide and p‐iodo­toluene. The mol­ecules contain three essentially planar parts, namely an amino­thio­phenol moiety (A), a toluene­sulfone moiety excluding the oxo ligands (B) and a tolyl group (C), approximately orthogonal to each other; the dihedral angles A/B, A/C and B/C are 111.6 (1), 89.3 (1) and 101.4 (1)°, respectively. Intermolecular N—H?O hydrogen bonds link the mol­ecules into infinite one‐dimensional chains.  相似文献   
72.
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74.
We present a detailed study of Raman spectroscopy and photoluminescence measurements on Li‐doped ZnO nanocrystals with varying lithium concentrations. The samples were prepared starting from molecular precursors at low temperature. The Raman spectra revealed several sharp lines in the range of 100–200 cm?1, which are attributed to acoustical phonons. In the high‐energy range two peaks were observed at 735 cm?1 and 1090 cm?1. Excitation‐dependent Raman spectroscopy of the 1090 cm?1 mode revealed resonance enhancement at excitation energies around 2.2 eV. This energy coincides with an emission band in the photoluminescence spectra. The emission is attributed to the deep lithium acceptor and intrinsic point defects such as oxygen vacancies. Based on the combined Raman and PL results, we introduce a model of surface‐bound LiO2 defect sites, that is, the presence of Li+O2? superoxide. Accordingly, the observed Raman peaks at 735 cm?1 and 1090 cm?1 are assigned to Li? O and O? O vibrations of LiO2.  相似文献   
75.
In this paper, we consider the New Agegraphic Dark Energy (NADE) model interacting with pressureless Dark Matter (DM) in the framework of generalized uncertainty principle. We consider different expressions of the scale factor a(t) pertaining to the emergent, the intermediate and the logamediate scenarios of the universe. We have derived the expressions for various cosmological parameters in all the three cases and plotted the equation of state (EoS) parameter ω D and squared speed of the sound $v_{s}^{2}$ to check the stability of the model in each case. We have observed that for emergent and intermediate cases, the EoS parameter has a quintom-like behavior and in the logamediate case it has quintessence-like behavior. The negative squared speed of sound in all of the three cases has indicated that the model is classically unstable for each choice of scale factor.  相似文献   
76.
Conditions for the total reflection x‐ray fluorescence (TXRF) analysis of real uranium samples for low atomic number elements using vacuum chamber TXRF spectrometer were optimized. It was observed that for analysis of low atomic number elements, almost complete removal of uranium matrix is required. Two certified reference materials of uranium containing trace elements in different concentrations were dissolved in minimum amount of high purity nitric acid. The uranium matrix from these solutions was separated by solvent extraction using tri‐n‐butyl phosphate as extracting reagent. Low atomic number elements in TXRF spectrum of the aqueous phase could be seen only after six tri‐n‐butyl phosphate equilibrations in extraction. The TXRF determinations of the certified low atomic number elements Mg and Al were made in these aqueous solutions after addition of Sc as an internal standard. The TXRF determined values for Mg were in good agreement with the certified values, whereas TXRF determined Al values differed from the certified values appreciably, probably due to the interference of Al Kα peak with escape peak of U Mα and the neighboring Si Kα peak. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
77.
In this paper, we consider a particular class of variational relation problem namely linear variational relation problem wherein the sets are defined by linear inequalities. The purpose is to study the existence of the solution set and its nature for this class of problem. Using these results, we provide algorithms to obtain the solutions of the problem based on which we present some numerical illustrations.  相似文献   
78.
Living anionic polymerization has been utilized to synthesize hydroxy end-functionalized PMMA macromonomers with styryl or allyl functionalities as the polymerizable end-groups. Protected hydroxy-functionalized alkyl lithium initiators have been used to initiate anionic polymerization of MMA. Subsequently the living chains with protected hydroxyl function have been terminated using 4-vinylbenzyl chloride (4-VBC) or allyl methacrylate (ALMA) to form α-hydroxy-ω-styryl and α-hydroxy-ω-allyl PMMA, respectively. These protected hydroxy-functionalized PMMA macromonomers have been characterized by GPC and 1H-NMR. Termination using 4-VBC led to 50% functionalization, whereas that using allyl methacrylate led to 100% functionalization of the hydroxy-PMMA.  相似文献   
79.
Multicellular tumor spheroid (MCTS) mimics microenvironment for tumor formation and provides predictive insight for in vivo tests. The hanging drop (HD) method of spheroid generation is cost effective, but it is limited by a long time duration for spheroid development and a low rate of formation of larger spheroids. Toward addressing those limitations, thermoresponsive copolymers with poly(N‐isopropylacrylamide) (p(NIPA)) backbone are developed, to be used as additives in the MCTS formation via HD method. Upon investigation it is found that in the presence of the polymer, robust and compact spheroids are formed in a short duration of 48 h. Larger spheroids (350–600 µm) can be formed by increasing the number of cells. Spheroids are characterized for their 3D shape and different cellular layers, and drug uptake study is done to prove the efficacy of the spheroids generated in drug screening.  相似文献   
80.
Relatively light sneutrinos which are experimentally allowed and are not theoretically disfavoured may significantly affect the currently popular search strategies for supersymmetric particles by decaying dominantly into an invisible channel. In certain cases the second lightest neutralino may also decay invisibly leading to two extra carriers of missing energy (in addition to the lightest supersymmetric particle (LSP))—the virtual LSPs (VLSPs). The lighter charginos which would be produced in pairs with reasonably large cross-sections at TEVATRON energies, decay dominantly into the hadronically quiet lepton+sneutrino (E T ) modes with large branching ratios leading to interesting unlike sign dilepton events which are not swamped by the standard model background. The kinematical cuts required to eliminate the backgrounds from WW, Drell-Yan and τ pair production are discussed in detail. With 100pb ?1 luminosity 10–35 background free events can be found in a large region of the SUSY parameter space.  相似文献   
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