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81.
Irina Georgescu 《Fuzzy Optimization and Decision Making》2007,6(4):367-389
In this paper we study two rationality indicators and two normality indicators of a fuzzy choice function. They express the
degree of rationality or normality of this fuzzy choice function. This way we can establish a hierarchy in a given family
of fuzzy choice functions with respect to their degree of rationality. 相似文献
82.
Rodica Olar Florentina Pătraşcu Mariana Carmen Chifiriuc Emilia Elena Iorgulescu Coralia Bleotu Luminiţa Măruţescu Veronica Lazar Dana Marinescu Nicolae Stanică Mihaela Badea 《Journal of Thermal Analysis and Calorimetry》2014,118(2):1159-1168
New species of type [MLCl2]·nH2O (M:Ni, n = 0; M:Cu, n = 1 and M:Zn, n = 0; L: 1,3,5,8,11-pentaazacyclotridecane-3-yl-(pyrid-3-yl)-methanone resulted by N,N’-bis(2-aminoethyl)ethane-1,2-diamine, nicotinamide and formaldehyde) were synthesised by one-pot condensation. Chemical analysis, ESI–MS, IR, 1H NMR, 13C NMR, UV–Vis–NIR, EPR spectroscopy as well as magnetic data at room temperature were used in order to characterise the compounds. The data provided by IR, ESI–MS and NMR spectra are consistent with the macrocycle formation. Electronic spectra indicate that both Ni(II) and Cu(II) adopt an octahedral stereochemistry data furthermore confirmed by magnetic moments and EPR spectrum at room temperature. The electrochemical behaviour of the compounds was investigated by cyclic voltammetry. Processes as water and chloride elimination as well as oxidative degradation of the macrocyclic ligand were observed by simultaneously TG–DTA measurements. The final residue as the most stable metallic oxide was identified by X-ray powder diffraction. The compound [CuLCl2]·H2O (2) exhibits fungicidal and anti-biofilm activity on Candida albicans strains. The complexes exhibit a low cytotoxicity on HEp 2 cells, except for Cu(II) species that induce the cellular cycle arrest in the G2/M phase. 相似文献
83.
Stig E. Friberg Qi Yin Florentina Pavel Raymond A. Mackay John D. Holbrey Kenneth R. Seddon 《Journal of Dispersion Science and Technology》2013,34(2):185-197
The amphiphilic association structures were determined in the system; water, Laureth 4 (approximately C12(EO) 4), and the ionic liquid l-butyl-3-methylimidazolium hexafluorophosphate ([bmim[PF6]), using visual observation and small angle x-ray diffraction. The system showed a lamellar liquid crystal solubilizing the ionic liquid ([bmim[PF6]) to a maximum of 15%, an isotropic surfactant solution dissolving the ionic liquid to a maximum of 39%, an isotropic ionic liquid solution with less than 0.5% of water and surfactant and finally, an aqueous solution with only traces of surfactant and ionic liquid. The small angle x-ray diffraction results showed the ionic liquid to be solubilized into the lamellar liquid crystal without changing the dimensions of the amphiphile layer or the interlayer spacing dependence on the water content. 相似文献
84.
V. Cojocaru D. I. Strumińska B. Skwarzec A. Pantelică E. Pincovschi I. I. Georgescu 《Journal of Radioanalytical and Nuclear Chemistry》2006,268(1):71-78
Summary Elemental concentrations of soil samples collected in the vicinity of a Romanian fertilizer plant were determined by EDXRF
and long half-life INAA. Lower limits of detection, obtained for various elements in soil by EDXRF technique with radioactive
excitation sources (238Pu and 241Am) and a HPGe detector are presented. Spurious effects characteristic for Ge detector X-ray spectrometry are evaluated and
discussed, and methods to overcome this drawback are suggested. Special care was taken to subtract from the spectra the Ge
Ka 相似文献
85.
86.
87.
We study spectral properties of a hamiltonian by analyzing the structure of certain C
*-algebras to which it is affiliated. The main tool we use for the construction of these algebras is the crossed product of
abelian C
*-algebras (generated by the classical potentials) by actions of groups. We show how to compute the quotient of such a crossed
product with respect to the ideal of compact operators and how to use the resulting information in order to get spectral properties
of the hamiltonians. This scheme provides a unified approach to the study of hamiltonians of anisotropic and many-body systems
(including quantum fields).
Received: 5 November 2001 / Accepted: 10 March 2002 相似文献
88.
The variational Gaussian wavepacket (VGW) approximation provides an alternative to path integral Monte Carlo for the computation of thermodynamic properties of many-body systems at thermal equilibrium. It provides a direct access to the thermal density matrix and is particularly efficient for Monte Carlo approaches, as for an N-body system it operates in a non-inflated 3N-dimensional configuration space. Here, we greatly accelerate the VGW method by retaining only the relevant short-range correlations in the (otherwise full) 3N × 3N Gaussian width matrix without sacrificing the accuracy of the fully coupled VGW method. This results in the reduction of the original O(N(3)) scaling to O(N(2)). The fast-VGW method is then applied to quantum Lennard-Jones clusters with sizes up to N = 6500 atoms. Following Doye and Calvo [JCP 116, 8307 (2002)] we study the competition between the icosahedral and decahedral structural motifs in Ne(N) clusters as a function of N. 相似文献
89.
M. Ulmeanu M. Filipescu N. D. Scarisoreanu G. Georgescu L. Rusen M. Zamfirescu 《Applied Physics A: Materials Science & Processing》2011,104(1):247-255
The selective removal and patterning of a typical pseudo-spin-valve structure, consisting of a Co(20 nm)/ Cu(6 nm)/Co(3 nm)
trilayer, by femtosecond laser has been examined in terms of irradiation parameters and layer structure. Ablation thresholds
of the individual Co and Cu thin films and the SiO2/Si substrate have been measured for single-shot irradiation with a 200 femtosecond (fs) laser pulses of a Ti:sapphire laser
operating at 775 nm. Ablation of the entire trilayer structure was characterized by a sequential removal of the layers at
a threshold level of fluence of 0.28 J/cm2. Atomic Force Microscopy, optical microscopy, profilometry and Sputtered Neutral Mass Spectroscopy were employed to characterize
the laser-induced single-shot laser selective removal and patterned areas. As a result, two phenomena were found to characterize
the laser process: (i) selective removal of the Co and Cu layer due to the change of the laser fluence and (ii) regular pillars’
area of Co/Cu/Co could be achieved in a regular manner with the lowest pillar width size of 1.5 μm. Ablation through the layers
was accompanied by the formation of bulges at the edges of the pillars, which was the biggest inconvenience in lowering the
pillar size through the femtosecond laser process. 相似文献
90.
Tinca Buruiana Violeta Melinte Florentina Jitaru Emil C. Buruiana Lavinia Balan 《Journal of polymer science. Part A, Polymer chemistry》2012,50(5):874-883
This work reports on the synthesis of three acid oligosiloxane‐urethane dimethacrylates and their use to obtain hybrid nanocomposite films, in which the presynthesized silver nanoparticles (NPs) were incorporated before photopolymerization, or produced via in situ photoreduction of the silver nitrate (AgNO3) precursor into the formulation, without any conventional reducing agent. All samples were characterized by 1H NMR, FT‐infrared and UV spectroscopies, photodifferential scanning calorimetry (photo‐DSC), transmission electron microscopy (TEM), and energy‐dispersive X‐ray (EDX) analysis. Fourier transformed infrared spectroscopy and photo‐DSC results showed that dimethacrylates having hydrophilic segment of poly(ethylene oxide) type in structure are more reactive than the acid oligosiloxane dimethacrylate. When another urethane dimethacrylate is taken as a comonomer, the photopolymerization rate (0.112–0.132 s?1) and the degree of conversion (82–93%) significantly increased. Experimental evidence of the existence of nanosilver into the polymer matrix generated upon UV irradiation has been supported by UV spectroscopy, EDX and TEM analysis, the last allowing a visualization of the formation of silver NPs with size between 2 and 15 nm. Mechanical parameters and wettability of the photocrosslinked films are also discussed in the prospect of further potential applications in the biomedical field. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献