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Huzhou, China

Mei Z.,Huzhou Teachers College | Korotkova O.,University of Miami
Optics Letters

Two classes of scalar, stochastic sources are introduced, each capable of producing far fields with intensities forming rings. Although the Bessel-Gaussian and the Laguerre-Gaussian Schell-model sources are described by two different math models, the behavior of their degrees of coherence and, hence, the shapes of their far fields are qualitatively similar. The new beams are of importance for optical methods of particle manipulation. © 2013 Optical Society of America. Source

Mei Z.,Huzhou Teachers College | Korotkova O.,University of Miami
Optics Letters

We introduce a new class of partially coherent sources of Schell type with cosine-Gaussian spectral degree of coherence and confirm that such sources are physically genuine. Further, we derive the expression for the cross-spectral density function of a beam generated by the novel source propagating in free space and analyze the evolution of the spectral density and the spectral degree of coherence. It is shown that at sufficiently large distances from the source the degree of coherence of the propagating beam assumes Gaussian shape while the spectral density takes on the dark-hollow profile. © 2013 Optical Society of America. Source

A class of random sources producing far fields self-splitting intensity profiles with variable spacing between the x and y directions is introduced. The beam conditions for ensuring the sources to generate a beam are derived. Based on the derived analytical expression, the evolution behavior of the beams produced by these families of sources in free space and turbulence atmospheric are explored and comparatively analyzed. By changing the modulation parameters n and m, the degree of coherence of Gaussian Schell-model source in the x and y directions are modulated respectively, and then the number of splitting beams and the spacing between splitting beams can be adjusted. It is illustrated that the selfsplitting intensity profile is stable when beams propagate in free space, but they eventually transformed into a Gaussian profiles when it passes at sufficiently large distances from its source through the turbulent atmosphere. © 2014 Optical Society of America. Source

A novel superabsorbent hydrogel has been synthesized with the crosslinking graft copolymerization of acrylic acid (AA) and acrylamide onto the chain of silk sericin. Potassium persulfate (KPS)-sodium sulfite (NaHSO3) as redox initiation system and N,N′-methylenebisacrylamide (MBA) as crosslinker were used. The structure of the product characterized by Fourier transform infrared absorption spectroscopy and the surface morphology of the hydrogel were observed by scanning electron microscopy. The certain parameters of the graft copolymerization including the monomer, the initiator, the crosslinker concentration, neutralization degree of AA, reaction temperature, and time weresystematically optimized to achieve a hydrogel with maximum swelling capacity (2150 g/g).The optimal conditions were initiator 8 mmol/L, MBA 2.5 mmol/L, neutralization degree of AA 75%, reaction temperature 55 C, and time 6 h. The swelling ratio in salt solutions was also determined(in 0.9% NaCl aqueous solution: 98 g/g). In addition, the swelling capability of the hydrogel was measured insolutions with pH ranged from 1 to 13. The synthesized hydrogel exhibited a pH-dependent character. Waterabsorbency of the product in aqueous chloride salt solutions has the Na+>Ca2+>Mg 2+>Al3+> order in the investigated concentration. © Springer-Verlag 2010. Source

Ouyang Y.,Huzhou Teachers College
Information Sciences

Fuzzy implication operators play important roles in both theoretical and applied aspects of fuzzy sets theory. Many papers investigated various properties of different types of implications and the interrelationships among these properties. In this paper, we exploit the minimal conditions which must be satisfied for a binary operation A to generate a residual implication with additional properties. It includes several examples to clarify the situation. © 2011 Elsevier Inc. All rights reserved. Source

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