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141.
We consider a nonlinear nonvariational periodic problem with a nonsmooth potential. Using the spectrum of the asymptotic (as |x| →?∞) differential operator and degree theoretic methods based on the degree map for multivalued perturbations of (S)?+? operators, we establish the existence of a nontrivial smooth solution. 相似文献
142.
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144.
Ana Maria Titoiu Roxana Porumb Pablo Fanjul‐Bolado Petru Epure Medana Zamfir Alina Vasilescu 《Electroanalysis》2019,31(11):2262-2273
In this work we investigate the performance of a simple, disposable electrochemical aptasensor for lysozyme and its usefulness for monitoring the allergen risk along wine production. The sensor relies on screen‐printed gold electrodes modified with gold nanoparticles as the electrochemical transducer, with detection by cyclic voltammetry. This simple method is characterized by a detection limit of 0.32 μg.mL?1 lysozyme and a linear range of 1–10 μg.mL?1, being appropriate for the analysis of lysozyme‐treated wines. Several white wines where sulphur dioxide was partially replaced by lysozyme were produced and analyzed with the aptasensor at critical stages during wine production. The results obtained with the aptasensor were moreover compared with those recorded in parallel by a standard method, high performance liquid chromatography (HPLC). The specific advantages brought by the use of nanomaterial and the limitations of the sensor are discussed. The sensor allowed evaluating the effect of various technological steps along wine production on the content of lysozyme. 相似文献
145.
Holló Berta Barta Petruševski Vladimir M. Kovács Gréta Bettina Franguelli Fernanda Paiva Farkas Attila Menyhárd Alfréd Lendvay György Sajó István E. Nagy-Bereczki Laura Pawar R. P. Szilágyi Imre Miklós Bódis Eszter Kótai László 《Journal of Thermal Analysis and Calorimetry》2019,138(2):1193-1205
Journal of Thermal Analysis and Calorimetry - A simple synthetic method was developed to prepare 4[Agpy2ClO4]·[Agpy4]ClO4 in a low-temperature decomposition process of [Agpy4]ClO4. A detailed... 相似文献
146.
Petru Jitaru Marco Roman Giulio Cozzi Paola Fisicaro Paolo Cescon Carlo Barbante 《Mikrochimica acta》2009,165(3-4):319-327
Silica gel and nanometer SiO2 modified with 4-(2-aminoethylamino)-N-(2-(2-aminoethyl amino)ethyl)butanamide (SG-AAEB and nanometer SiO2-AAEB), which were prepared based on chemical immobilization, were used as sorbents for the solid phase extraction of Cu(II), Fe(III), and Pb(II) prior to their determination by inductively coupled plasma optical emission spectrometry. Adsorption efficiencies of the two sorbents towards metal ions were investigated by batch and column procedures. For both sorbents the preconcentration conditions of analytes including effects of pH, shaking time, sample flow rate and adsorption capacity, were investigated and compared. The differences of silica gel and nanometer SiO2 in sizes and surface structures resulted in distinct chemical activity and selectivity toward metals. At pH 4, the adsorption capacity of SG-AAEB was found to be 12.2, 14.5 and 9.8 mg g?1 for Cu(II), Fe(III), and Pb(II), respectively. In comparison, nanometer SiO2-AAEB showed a high selectivity toward Pb(II) and has a much larger adsorption capacity (22.3 mg g?1). Furthermore, the application of SG-AAEB and nanometer SiO2-AAEB for simultaneous preconcentration of trace Cu(II), Fe(III), and Pb(II) from natural samples was performed with satisfactory results. 相似文献
147.
Wakeham D Niga P Ridings C Andersson G Nelson A Warr GG Baldelli S Rutland MW Atkin R 《Physical chemistry chemical physics : PCCP》2012,14(15):5106-5114
The nanostructure of the ethanolammonium nitrate (EtAN)-air surface has been investigated using X-ray reflectometry (XRR), vibrational sum frequency spectroscopy (VSFS) and neutral impact collision ion scattering spectroscopy (NICISS). The XRR data decays more rapidly than expected for a perfectly sharp interface, indicating a diffuse electron (scattering length) density profile. Modelling of the XRR data using three different fitting routines produced consistent interfacial profiles that suggest the formation of interfacial EtAN clusters. Consistent with this, VSFS reveals that the EtAN surface is predominantly covered by -CH(2)- moieties, with the -NH(3)(+) and -OH groups of the cation buried slightly deeper in the interface. The elemental profiles determined using NICISS also show enrichment of carbon relative to nitrogen and oxygen in the outermost surface layer, which is consistent with the surface cation orientation deduced from VSFS, and with the presence of EtAN aggregates at the liquid surface. 相似文献
148.
Let X be a reflexive and smooth real Banach space which has a weakly sequentially continuous duality mapping. In this paper, we consider the following viscosity approximation scheme xn+1=λn+1f(xn)+(1−λn+1)Tn+1xn (where f is a generalized contraction mapping) for infinitely many nonexpansive self-mappings T1,T2,T3,… in X. We establish a strong convergence result which generalizes some results in the literature. 相似文献
149.
Sakat E Vincent G Ghenuche P Bardou N Collin S Pardo F Pelouard JL Haïdar R 《Optics letters》2011,36(16):3054-3056
We present the experimental study of a free-standing metallic guided-mode resonant structure, for bandpass filtering applications in the mid-IR wavelength range. Structure consists of a subwavelength gold grating with narrow slits deposited on a silicon nitride membrane. High optical transmission is measured with up to 78% transmission at resonance. Angularly resolved spectra are presented revealing Fano-type resonance. 相似文献
150.
This paper deals with a method for approximating a solution of the following problem: find hierarchically a common fixed point
of a finite family of nonself nonexpansive mappings with respect to a nonexpansive self mapping on a closed convex subset
of a smooth and reflexive Banach space X, which admits a weakly sequentially continuous duality mapping. First, we prove a weak convergence theorem which extends
and improves one recent result proved by Yao and Liou (see Inverse Problems 24 (2008), doi:). Secondly, when the self mapping is a contraction, we prove, under different restrictions on parameters, a strong convergence
result which generalize some recent results in the literature. 相似文献