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51.
Meyerheim HL Sander D Popescu R Pan W Popa I Kirschner J 《Physical review letters》2007,99(11):116101
The x-ray structure analysis of the oxygen-surfactant-mediated growth of Ni on Cu(001) identifies up to 0.15 monolayers of oxygen in subsurface octahedral sites. This questions the validity of the general view that surfactant oxygen floats on top of the growing Ni film. Rather, the surfactant action is ascribed to an oxygen-enriched zone extending over the two topmost layers. Surface stress measurements support this finding. Our results have important implications for the microscopic understanding of surfactant-mediated growth and the change of the magnetic anisotropy of the Ni films. 相似文献
52.
Smaranda Iliescu Lavinia Macarie Adriana Popa Aurelia Visa Bianca Maranescu 《Phosphorus, sulfur, and silicon and the related elements》2014,189(7-8):992-1003
AbstractTwo new series of solid polymer electrolytes (SPEs) based on phosphorus containing (co)polyesters (PPE) and Lithium triflate were obtained. PPEs are composed of phosphonate moeties (cyclohexyldichlorophosphonate (CHDP)) as linking agent and two diols: PEG (6000) and poly(tetramethylene glycol) (PTMG) in PPE I, and PEG (6000) and 4,4′-cyclohexylidenebisphenol (bisphenol Z, BZ) in PPE II. Polycondensation was carried out in solution in the presence of triethylamine (TEA) as scavenger of HCl side product (PPE I–IIa) and in the absence of any acid acceptor (PPE I–IIb). The Limiting Oxygen Index (LOI) and thermal analysis were performed both on polymers and membranes. The ionic conductivity of SPE membranes based on PPE-salt complexes, with various salt concentrations, was investigated at different temperature and ionic transference numbers were determined. Optimum composition was obtained for the polymer which contains in structure only alkyl units and 15% Lithium triflate. 相似文献
53.
Cristina Bucur Mihaela Badea Mariana Carmen Chifiriuc Coralia Bleotu Emilia Elena Iorgulescu Irinel Adriana Badea Maria Nicoleta Grecu Veronica Lazăr Oana-Irina Patriciu Dana Marinescu Rodica Olar 《Journal of Thermal Analysis and Calorimetry》2014,115(3):2179-2189
Novel complexes of M2LCl4·nH2O type (M:Ni, n = 4; M:Cu, n = 3 and M:Zn, n = 0; L: ligand resulted from 1,4-phenylenediamine, 3,6-diazaoctane-1,8-diamine and formaldehyde one-pot condensation) were synthesized and characterised by microanalytical, ESI–MS, IR, UV–Vis, 1H NMR and EPR spectra, magnetic data at room temperature and molar conductivities as well. The electrochemical behaviour of complexes was investigated by cyclic voltammetry. Simultaneous TG/DTA measurements were performed in order to evidence the thermal behaviour of the obtained complexes. Processes such as water elimination, fragmentation and oxidative degradation of the organic ligand as well as chloride elimination occurred during thermal decomposition. The antimicrobial assays demonstrate that the compounds exhibited good antibacterial activity, especially against S. aureus and E. coli strains, the most active being the copper(II) complex, which also exhibited the most prominent anti-biofilm effect, suggesting its potential use for the development of new antimicrobial agents. The biological activity was correlated with log P ow values. All complexes disrupt the membrane integrity of HCT 8 tumour cells. 相似文献
54.
Mihaela Badea Larisa Calu Mariana Carmen Chifiriuc Coralia Bleotu Alexandra Marin Sebastian Ion Gabriela Ioniţă Nicolae Stanică Luminiţa Măruţescu Veronica Lazăr Dana Marinescu Rodica Olar 《Journal of Thermal Analysis and Calorimetry》2014,118(2):1145-1157
A series of complexes of type [ML(CH3COO)(OH2)2] (M: Co, Ni; HL: 2-[(E)-1H-1,2,4-triazol-3-ylimino)methyl]phenol)) and [M2L2(CH3COO)2(OH2)n] (M: Cu, n = 2; M: Zn, n = 0) were synthesised by template condensation. The compounds were characterised with microanalytical, ESI–MS, IR, electronic, EPR spectra and magnetic data at room temperature. Based on the IR and ESI–MS spectra, a dinuclear structure with the acetate as bridge was proposed for Cu(II) and Zn(II) complexes. The dinuclear structure of Cu(II) complex is also consistent with both magnetic behaviour and EPR spectrum. The thermal analyses have evidenced processes as water elimination, acetate decomposition, as well as oxidative degradation of the Schiff base. The final decomposition product was the most stable metal oxide as indicated by powder X-ray diffraction. The cobalt and copper compounds exhibited a broad spectrum of antibacterial activity towards both planktonic and biofilm-embedded cells. The complexes exhibit a low cytotoxicity except for Cu(II) species that induces the early apoptosis for the HEp 2 cells. 相似文献
55.
Preparation of organic polymer monolithic columns in fused silica capillaries was aimed at fast gradient separation of proteins. For this purpose, polymerization in situ procedure was optimized, using ethylene dimetacrylate and butyl metacrylate monomers with azobisisobutyronitrile as initiator of the polymerization reaction in presence of non-aqueous porogen solvent mixtures composed of 1-propanol and 1,4-butanediol. The separation of proteins in totally monolithic capillary columns was compared with the chromatography on a new type of "hybrid interparticle monolithic" capillary columns, prepared by in situ polymerization in capillary packed with superficially porous spherical beds, 37-50 microm. The "hybrid" columns showed excellent stability and improved hydrodynamic flow properties with respect to the "totally" monolithic capillary columns. The separation selectivity is similar in the two types of columns. The nature of the superficially porous layer (bare silica or bonded C18 ligands) affects the separation selectivity less significantly than the porosity (density) of the monolithic moiety in the interparticle space, controlled by the composition of the polymerization mixture. The retention behaviour of proteins on all prepared columns is consistent with the reversed-phase gradient elution theory. 相似文献
56.
Mihaela Badea Rodica Olar Dana Marinescu Gina Vasile 《Journal of Thermal Analysis and Calorimetry》2008,92(1):209-214
A series of new complexes with mixed ligands of the type [ML(C3H3O2)2]·nH2O (((1)
M=Mn, n=1; (2)
M=Co(II), n=2; (3)
M=Ni(II), n=4; (4)
M=Cu(II), n=1.5; (5)
M=Zn(II), n=0; L=3-amino-1,2,4-triazole and (C3H3O2)=acrylate anion) were synthesized and characterised by chemical analysis and IR data. In all complexes the 3-amino-1,2,4-triazole
acts as bridge while the acrylate acts as bidentate ligand except for complex (5) where it is found as unidentate. The thermal behaviour steps were investigated in nitrogen flow. The thermal transformations
are complex processes according to TG and DTG curves including dehydration, acrylate ion and 3-amino-1,2,4-triazole degradation
respectively. The final products of decomposition are the most stable metal oxides, except for complex (4) that leads to metallic copper. 相似文献
57.
Dana J. DiScenza 《Supramolecular chemistry》2016,28(11-12):881-891
Reported herein is the selective detection of aliphatic alcohols using cyclodextrin-promoted, proximity-induced fluorescence modulation of a high-quantum yield fluorophore. This fluorescence modulation occurred when the analyte was held in close proximity to the fluorophore via non-covalent cyclodextrin–analyte–fluorophore interactions, and led to unique modulation responses for each analyte, fluorophore and cyclodextrin investigated. These changes in fluorescence were used for the generation of an array using linear discriminant analysis that successfully generated unique pattern identifiers for 99% of the investigated analytes, and could detect alcohols at micromolar concentrations. These results represent a fundamentally new detection approach for these challenging analytes, and have significant potential in the development of novel detection schemes. 相似文献
58.
59.
Christopher G. Hamaker Oksana S. Maryashina Dana K. Daley Andrew L. Wadler 《Journal of chemical crystallography》2010,40(1):34-39
Abstract
The crystal structures of the new compounds 5-bromo-N-[2-(methylthio)-phenyl]salicylaldimine (1), and 3,5-dichloro-N-[2-(methylthio)phenyl]salicylaldimine (2) were obtained by single crystal X-ray diffraction. Compound 1 crystallizes in the monoclinic space group P21/c with a = 14.1479(14) ?, b = 5.3058(3) ?, c = 19.104(3) ?; β = 106.218(10)°; and Z = 4. Compound 2 crystallizes in the triclinic space group $ P\bar{1} $ P\bar{1} with a = 11.2249(10) ?, b = 13.863(2) ?, c = 13.9055(9) ?; and α = 99.378(15)°, β = 102.866(7)°, γ = 91.375(11)°; and Z = 6. Details of the synthesis, structures, and spectroscopic properties of the new compounds are discussed. 相似文献60.
Dontchev et al. [4] introduced the notion of ℐ-g-closed sets. In [16], the further properties of ℐ-g-closed sets are investigated. In this paper, we introduce the notion of ℐ-mg-closed sets and obtain the unified characterizations for certain families of subsets between *-closed sets and ℐ-g-closed sets in an ideal topological space. 相似文献