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991.
By employing the generalized Riccati transformation technique, we will establish some new oscillation criteria and study the
asymptotic behavior of the nonoscillatory solutions of the second-order nonlinear neutral delay dynamic equation
, on a time scale . The results improve some oscillation results for neutral delay dynamic equations and in the special case when = ℝ our results cover and improve the oscillation results for second-order neutral delay differential equations established
by Li and Liu [Canad. J. Math., 48 (1996), 871–886]. When = ℕ, our results cover and improve the oscillation results for second order neutral delay difference equations established
by Li and Yeh [Comp. Math. Appl., 36 (1998), 123–132]. When =hℕ, = {t: t = q
k
, k ∈ ℕ, q > 1}, = ℕ2 = {t
2: t ∈ ℕ}, = = {t
n
= Σ
k=1
n
, n ∈ ℕ0}, ={t
2: t ∈ ℕ}, = {√n: n ∈ ℕ0} and ={: n ∈ ℕ0} our results are essentially new. Some examples illustrating our main results are given.
相似文献
992.
The existence of multiple positive solutions is presented for the singular second-order boundary value problems
using the fixed point index, where f may be singular at x = 0 and x′ = 0.
The project is supported by the fund of natural science of Shandong Province. 相似文献
993.
Wang X Lu D Austin R Agarwal A Mueller LJ Liu Z Wu J Feng P 《Langmuir : the ACS journal of surfaces and colloids》2007,23(10):5735-5739
Herein we report a new strategy for protein refolding by taking advantage of the unique surface and pore characteristics of ethylene-bridged periodic mesoporous organosilica (PMO), which can effectively entrap unfolded proteins and assist refolding by controlled release into the refolding buffer. Hen egg white lysozyme was used as a model protein to demonstrate the new method of protein refolding. Through loading of denatured proteins inside uniform mesoporous channels tailored to accommodate individual protein, protein aggregation was minimized, and the folding rate was increased. Poly(ethyleneglycol) (PEG)-triggered continuous release of entrapped denatured lysozyme allowed high-yield refolding with high cumulative protein concentrations. The new method enhances the oxidative refolding of lysozyme (e.g., over 80% refolding yield at about 0.6 mg/mL). 相似文献
994.
We report our studies on the refractive indices and twist viscoelastic coefficient of novel thiol terminated alkoxy-cyanobiphenyl nematic liquid crystals. Dynamic light scattering (DLS) was employed to measure the twist viscoelastic coefficient as a function of temperature and the length of alkoxy chain. Our studies show that the twist viscoelastic coefficient is about three times smaller than that of the ordinary alkoxy-cyanobiphenyl nematic liquid crystals. DLS experiments carried out on this system with applied electric field show that the director relaxation frequency increases. These measurements yield the ratio of dielectric anisotropy to twist viscosity. We have also estimated the activation energy corresponding to twist viscosity. 相似文献
995.
Some new criteria for the oscillation of fourth-order nonlinear functional differential equations of the form
are established.
Published in Ukrains’kyi Matematychnyi Zhurnal, Vol. 59, No. 3, pp. 291–313, March, 2007. 相似文献
996.
The relationship between structural order metrics and the excess entropy is studied using the transferable rigid ion model (TRIM) of beryllium fluoride melt, which is known to display waterlike thermodynamic anomalies. The order map for liquid BeF2, plotted between translational and tetrahedral order metrics, shows a structurally anomalous regime, similar to that seen in water and silica melt, corresponding to a band of state points for which average tetrahedral (q(tet)) and translational (tau) order are strongly correlated. The tetrahedral order parameter distributions further substantiate the analogous structural properties of BeF2, SiO2, and H2O. A region of excess entropy anomaly can be defined within which the pair correlation contribution to the excess entropy (S2) shows an anomalous rise with isothermal compression. Within this region of anomalous entropy behavior, q(tet) and S2 display a strong negative correlation, indicating the connection between the thermodynamic and the structural anomalies. The existence of this region of excess entropy anomaly must play an important role in determining the existence of diffusional and mobility anomalies, given the excess entropy scaling of transport properties observed in many liquids. 相似文献
997.
Ravi P. Agarwal Ghaus Ur Rahman Muhsina 《Mathematical Methods in the Applied Sciences》2023,46(2):2801-2839
In this article, we formulate fractional differential inclusion of pantograph type (IFDIP), incorporating impulsive behavior of the solution. The boundary conditions taken into account are nonlocal in nature. We will consider the convex problem and prove the Filippov–Wazewski-type theorem. Moreover, existence of solution, uniqueness of a solution, and the topological properties of the solution's set will be examined for the problem under consideration. In the second part, the study will be confined to the second-order impulsive fractional differential equation of pantograph type. For certain geometric characteristics of the solution's set, Aronszajn–Browder–Gupta-type results will be explored for the newly introduced differential equation. Also, it will prove the existence of solution for the first-order fractional differential equation of pantograph type having impulsive behavior of the solution. 相似文献
998.
999.
Antimicrobial sutures were prepared by the radiation grafting of acrylonitrile monomer onto polypropylene (PP) monofilament. The grafted sutures were subsequently hydrolyzed to transform nitrile groups into carboxylic groups for the immobilization of antimicrobial drug, tetracycline hydrochloride (TC). The modified sutures show continuous release of drug for a period of 4–5 days. The antimicrobial activity of the sutures was determined against both Gram positive and Gram negative bacteria by the zone of inhibition technique. Zone of inhibition was observed around the drug‐containing sutures in the plate inoculated with Escherichia coli (E. coli), Klebsiella pneumonea (K. pneumonea), and Staphylococcus aureus (S. aureus). The results of infection studies in albino rats against S. aureus showed no infection even after fourth postoperative day of surgery. This is because of the release of the TC drug at the site of injury, which inhibits the bacterial growth. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
1000.
Integral transform and fractional derivative formulas involving the extended generalized hypergeometric functions and probability distributions
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H. M. Srivastava Ritu Agarwal Sonal Jain 《Mathematical Methods in the Applied Sciences》2017,40(1):255-273
In the present paper, our aim is to establish several formulas involving integral transforms, fractional derivatives, and a certain family of extended generalized hypergeometric functions. As corollaries and consequences, many interesting results are shown to follow from our main results. A probability density function involving the extended generalized hypergeometric function is introduced, and its properties are studied. The corresponding properties of some of the classical probability distributions and their associated probability density functions are easily derivable as special cases of our general results. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献