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161.
162.
The Fu?ík spectrum for systems of second order ordinary differential equations with Dirichlet or Neumann boundary values is considered: it is proved that the Fu?ík spectrum consists of global C1 surfaces, and that through each eigenvalue of the linear system pass exactly two of these surfaces. Further qualitative, asymptotic and symmetry properties of these spectral surfaces are given. Finally, related problems with nonlinearities which cross asymptotically some eigenvalues, as well as linear-superlinear systems are studied. 相似文献
163.
164.
Eugenio Frola 《Annali di Matematica Pura ed Applicata》1937,16(1):165-182
Continuazione della Parte I, pubblicata collo stesso titolo a p. 127 di questo volume degli ? Annali di Matematica ?. 相似文献
165.
Giovanni Caprioli Gloria Cristalli Eugenio Ragazzi Laura Molin Massimo Ricciutelli Gianni Sagratini Roberta Seraglia Yanting Zuo Sauro Vittori 《Rapid communications in mass spectrometry : RCM》2010,24(19):2843-2848
Matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS) was used in this study to obtain protein fingerprints of seven different lentil varieties, to characterize their differences and similarities. Two different matrices have been tested in order to obtain reproducible and significant mass spectra. Extraction with water containing 0.1% of trifluoroacetic acid has been used as preparative step to obtain hydrophilic protein samples of lentil seeds. The obtained MALDI protein profiles identified clear differences between the seven studied lentil varieties. Moreover, considering the high complexity of the obtained MALDI spectra, multivariate techniques of data analysis were employed to find further classification details. These multivariate analyses confirmed the possibility of a clear classification of the seven lentil varieties, indicating that the proposed procedure can be a valid taxonomic tool, and a method to certify the origin of lentils, useful for high added value lentils (Italian lentils). Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
166.
Antonio Doménech‐Carbó Eugenio Coronado Pilar Díaz Antonio Ribera 《Electroanalysis》2010,22(3):293-302
Electrochemical characterization of palladium nanoparticles surrounded by a palladium oxide shell (Pd@PdO) is described from a combination of voltammetry plus electrochemical quartz crystal microbalance experiments at nanoparticle deposits on graphite electrodes in contact with aqueous H2SO4 and NaOH solutions. A method for determining the metal core size and oxide shell thickness of the Pd@PdO nanoparticles, based on a combination of conventional voltammetry of nanoparticles in DMSO solution and voltammetry of nanoparticle deposits in contact with 0.10 M aqueous NaOH solution, is described. 相似文献
167.
Vivian C. Selma Luís H. B. Cotrim José A. D. Rodrigues Suzana M. Ratusznei Marcelo Zaiat Eugenio Foresti 《Applied biochemistry and biotechnology》2010,162(8):2365-2380
The effect of organic matter and fill time on anaerobic sequencing batch reactor (5 L, 30°C, 8-h cycles, 50 rpm) efficiency
has been analyzed. Organic matter was increased by the influent concentration. Fill times investigated were in the batch mode
and fed-batch followed by batch. In the batch mode organic matter removal were 93%, 81%, and 66% for influent concentration
of 500, 1,000, and 2,000 mgCOD/L (0.6, 1.29, and 2.44 gCOD/L.d), respectively. At 3,000 mgCOD/L (3.82 gCOD/L.d) operational
stability could not be achieved. Removal efficiency was improved by increasing the fill time, and was 85% for the 1,000 mgCOD/L
condition and fill times of 2 and 4 h, and 80 and 77% for the 2,000 mgCOD/L condition and fill times of 2 and 4 h, respectively.
Hence, gradual feeding seemed to improve and to smooth the profiles of organic matter and volatile acids along the cycle with
78 to 96 NmLCH4/gCOD. 相似文献
168.
169.
Clemente-León M Coronado E Soriano-Portillo A Colacio E Domínguez-Vera JM Galvez N Madueño R Martín-Romero MT 《Langmuir : the ACS journal of surfaces and colloids》2006,22(16):6993-7000
Magnetic Langmuir-Blodgett films of four ferritin derivatives with different iron contents containing 4220, 3062, 2200, and 1200 iron atoms, respectively, have been prepared by using the adsorption properties of a 6/1 mixed monolayer of methyl stearate (SME) and dioctadecyldimethylammonium bromide (DODA). The molecular organization of the mixed SME/DODA monolayer is strongly affected by the presence of the water-soluble protein in the subphase as shown by pi-A isotherms, BAM images, and imaging ellipsometry at the water-air interface. BAM images reveal the heterogeneity of this mixed monolayer at the air-water interface. We propose that the ferritin is located under the mixed matrix in those regions where the reflectivity is higher whereas the dark regions correspond to the matrix. Ellipsometric angle measurements performed in zones of different brightness of the mixed monolayer confirm such a heterogeneous distribution of the protein under the lipid matrix. Transfer of the monolayer onto different substrates allowed the preparation of multilayer LB films of ferritin. Both infrared and UV-vis spectroscopy indicate that ferritin molecules are incorporated within the LB films. AFM measurements show that the heterogeneous distribution of the ferritin at the water-air interface is maintained when it is transferred onto solid substrates. Magnetic measurements show that the superparamagnetic properties of these molecules are preserved. Thus, marked hysteresis loops of magnetization are obtained below 20 K with coercive fields that depend on the number of iron atoms of the ferritin derivative. 相似文献
170.
Gómez-García CJ Coronado E Curreli S Giménez-Saiz C Deplano P Mercuri ML Pilia L Serpe A Faulmann C Canadell E 《Chemical communications (Cambridge, England)》2006,(47):4931-4933
The novel paramagnetic and chiral anion [Fe(C5O5)3]3- has been combined with the organic donor BEDT-TTF (= ET = bis(ethylenedithio)tetrathiafulvalene) to yield the first chirality-induced alpha phase and a paramagnetic metal. 相似文献