Absorption saturation and self-action processes under resonant excitation of the basic exciton transition in CdSe/ZnS colloidal quantum dots

The revealed absorption saturation and Fresnel diffraction of ultrashort laser pulses under resonant excitation of the basic exciton transition in CdSe/ZnS quantum dots (a strongly absorbing colloidal solution) have been explained by the processes of filling of states of a two-level system with the excited-state lifetime dependent on the light intensity and self-diffraction of the laser beam due to the formation of the transparency channel and the induced diaphragm.     

Synthesis and cytotoxicity of novel γ-piperidone-containing dibenzo-1,7-diaza-14-crown-4 ethers

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Hybrid Projection Algorithm for Two Finite Families of Asymptotically Quasi ϕ-Nonexpansive Mappings in Reflexive Banach Spaces

In this paper, we introduce a hybrid projection algorithm for two finite families of asymptotically quasi ?-nonexpansive mappings to establish a convergence theorem in smooth, strictly convex, and reflexive Banach spaces. As applications, we state the convergence of hybrid projection algorithm for two finite families of asymptotically quasi-nonexpansive mappings in Hilbert spaces and the convergence for a system of equilibrium problems.     

Convergence of a hybrid viscosity approximation method for finding zeros of m-accretive operators

Numerical Algorithms - For finding a zero of an m-accretive operator in a real Banach space, we consider an implicit hybrid viscosity approximation method and show that its explicit variant...     

On contraction of nonlinear difference equations with time‐varying delays

General nonlinear difference equations with time‐varying delays are considered. Explicit criteria for contraction of such equations are presented. Then some simple sufficient conditions for global exponential stability of equilibria and for stability of invariant sets are derived. Furthermore, explicit criteria for existence, uniqueness and global exponential stability of periodic solutions are derived. Finally, the obtained results are applied to time‐varying discrete‐time neural networks with delay.     

Parallel methods for regularizing systems of equations involving accretive operators

In this paper, two parallel methods for solving systems of accretive operator equations in Banach spaces are studied. The convergence analysis of the methods in both free-noise and noisy data cases is provided.     

A new shrinking gradient-like projection method for equilibrium problems

The paper proposes a new shrinking gradient-like projection method for solving equilibrium problems. The algorithm combines the generalized gradient-like projection method with the monotone hybrid method. Only one optimization program is solved onto the feasible set at each iteration in our algorithm without any extra-step dealing with the feasible set. The absence of an optimization problem in the algorithm is explained by constructing slightly different cutting-halfspace in the monotone hybrid method. Theorem of strong convergence is established under standard assumptions imposed on equilibrium bifunctions. An application of the proposed algorithm to multivalued variational inequality problems (MVIP) is presented. Finally, another algorithm is introduced for MVIPs in which we only use a value of main operator at the current approximation to construct the next approximation. Some preliminary numerical experiments are implemented to illustrate the convergence and computational performance of our algorithms over others.     

Facile synthesis and antibacterial activity of silver nanoparticles-modified graphene oxide hybrid material: the assessment,utilization, and anti-virus potentiality

The present work reported the one-pot preparation of silver nanoparticles doped with graphene oxide (Ag@GO), using glucose as an eco-friendly reducing agent. The effects of synthesis conditions on the introduction of AgNPs onto graphene oxide sheets were confirmed by modern analytical techniques and antibacterial assays. Results showed that the Ag@GO-4 sample prepared with glucose:AgNO₃:GO mass ratio of 1:1:1 at 60 °C for 60 min exhibited an appropriate one for further studies with AgNPs sizing of 16.66 ± 3.73 nm. The Ag@GO-4 effectively inhibited the development of S. enterica, P. aeruginosa, and S. aureus with the 50 % inhibitory concentration at 14.5, 0.9, and 6.8 μg/mL, respectively. The simultaneous effects of Ag@GO concentration, pH, interaction time, annealing temperature, and bacterial density on the antibacterial activity of Ag@GO-4 were also investigated by Plackett-Burman and Box-Behnken design. The optimal values deducing for Ag@GO-4 concentration, pH, and bacterial density were 40 μg/mL, 5.5, and 5.1 × 10⁶ CFU/mL, respectively, which could impressively reach 99.99 % of S. enterica elimination in practice. The interaction time and annealing temperature implied a negligible effect on the antibacterial activity of Ag@GO-4. All results of the present study affirmed the future use of Ag@GO not only as an efficient antibacterial agent but also potentially as a novel anti-virus method of treatment.