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21.
Jeon IeR Ababei R Lecren L Li YG Wernsdorfer W Roubeau O Mathonière C Clérac R 《Dalton transactions (Cambridge, England : 2003)》2010,39(20):4744-4746
In an attempt to develop novel coordination networks of SMMs, a Cu(II) picolinate complex has been used to coordinate S(T) = 9 tetranuclear Mn-based SMMs resulting in an intriguing 2D framework exhibiting a magnet-like behavior at low temperature. 相似文献
22.
The microstructure of water soluble nanoaggregates based on polyelectrolyte complex formed by the cationic comb-type copolymer
poly(acrylamide -co-[3- (methacryloyl-amino)propyl] trimethylammonium chloride)-graft- polyacrylamide [P(AM-co-MAPTAC)-g-PAM]
and the anionic linear polyelectrolyte sodium polyacrylate (NaPA) was investigated using the fluorescence probe technique.
The fluorescence probe were 1-anilinonaphthalene-8-sulfonic acid (ANS), pyrene (Py) and 1,10-bis(1-pyrene) decane (PD). The
fluorescence properties in polyelectrolyte complex solutions, which are sensitive to either micropolarity (ANS, Py) or microviscosity
(PD), were related to the quantities obtained in different pure or mixed solvents. Micropolarities were quantified utilizing
the polarity common index (Reichardt) E
T(30). ANS and Py showed a variation of the micropolarity with the charge ratio of the two polymers, with the lowest polarity
reached at the complex neutralization. The PD probe, by its excimer-to-monomer fluorescence intensities ratio, enabled us
to evidence the effect of the composition and the comb-type copolymer grafting density on the microviscosity of the interpolyelectrolytes
aggregates. It has been found that the microviscosity increased with the density of the grafting PAM chains. 相似文献
23.
The paper analyses the effect of normal contact with friction on the generation of full band-gaps in sonic composites. The behavior of contact interfaces are computed by using LISA (local interaction simulation approach). LISA is an efficient tool for numerical simulation of the acoustic wave propagation in heterogeneous material specimens, in particular those with contact interfaces between different materials, like in sonic composites. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Experimental results for the temperature dependence of density at normal pressure for two compositions of sodium lauryl sulphate/decanol/water solutions, exhibiting either a calamitic or a discotic lyotropic nematic phase at room temperature, are presented. Within the limits of experimental precision (±1 ×10-5 g cm-3), the systems show no jump in density at the nematic to isotropic phase transition. Over the studied temperature range, the mean thermal expansion coefficients were also evaluated. 相似文献
27.
Tree-connected peer group situations and peer group games 总被引:2,自引:0,他引:2
28.
Petre Ionita Vasile Dinoiu Cornel Munteanu Ioana Maria Turcu Victorita Tecuceanu Traian Zaharescu Eliza Oprea Cornelia Ilie Dan Anghel Gabriela Ionita 《Chemical Papers》2015,69(6):872-880
The rosemary extract was encapsulated in polyethylene or in covalently-based network gels. The covalent gels were obtained by the reaction of isocyanate end-capped polyethylene glycol (PEG) with β-cyclodextrin or glycerol. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay was used to evaluate the antioxidant activity (AA) of rosemary extract entrapped in polymeric structures and in ethanol or water solutions. The AA of the rosemary extract was determined using a DPPH radical for samples prepared in ethanol, and a water-soluble derivative, the sulphonated DPPH radical (DPPH-SO3Na), for the rosemary extract in water. Formulation of the rosemary extract in polymeric gels ensures a rapid release which determines the AA values similar to those in solution. 相似文献
29.
Alessandro Fonda Rodica Toader 《Nonlinear Analysis: Theory, Methods & Applications》2011,74(7):2485-2496
We prove the existence of infinitely many periodic solutions for radially symmetric systems with a singularity of repulsive type. The nonlinearity is assumed to have a linear growth at infinity, being controlled by two constants which have a precise interpretation in terms of the Dancer-Fu?ik spectrum. Our result generalizes an existence theorem by Del Pino et al. (1992) [4], obtained in the case of a scalar second order differential equation. 相似文献
30.
Rodica Olar Mihaela Badea Dana Marinescu Larisa Calu Cristina Bucur 《Journal of Thermal Analysis and Calorimetry》2011,105(2):571-575
Novel complexes of type [M2LCl4]·nH2O ((1) M:Ni, n = 5; (2) M:Cu, n = 0 and (3) M:Zn, n = 2; L: ligand resulted from 1,2-phenylenediamine, 3,6-diazaoctane-1,8-diamine and formaldehyde template condensation) were
synthesised and characterised. The features of complexes have been assigned from microanalytical, IR and UV–Vis data. The
thermal analyses have evidenced the thermal intervals of stability and also the thermodynamic effects that accompany them.
Processes as water or hydrochloric acid elimination as well as oxidative degradation of the organic ligand were observed.
Complexes display a different thermal behaviour as result of dissimilar chemical interaction of metal ions with chloride anions.
The final product of decomposition was metal(II) oxide as powder X-ray diffraction indicated. 相似文献