Adaptive stabilization of an incommensurate fractional order chaotic system via a single state controller

In this paper, we investigate the stabilization of an incommensurate fractional order chaotic systems and propose a modified adaptive-feedback controller for the incommensurate fractional order chaos control based on the Lyapunov stability theory, the fractional order differential inequality and the adaptive control theory. The present controller, which only contains a single state variable, is simple both in design and in implementation. The simulation results for several fractional order chaotic systems are provided to illustrate the effectiveness of the proposed scheme.

Influence of time-periodic potentials on electronic transport in double-well structure

Within the framework of the Floquet theorem, we have investigated single-electron photon-assisted tunneling in a double-well system using the transfer matrix technique. The transmission probability displays satellite peaks on both sides of the main resonance peaks and these satellite peaks originate from emission or absorption photons. The single-electron resonance tunneling can be controlled through changing the applied harmonically potential positions, such as driven potential in wells, in barriers, or in whole double-well systems. This advantage should be useful in the optimization of the parameters of a transmission device.

Adaptive lag synchronization and parameter identification of fractional order chaotic systems

This paper proposes a simple scheme for the lag synchronization and the parameter identification of fractional order chaotic systems based on the new stability theory. The lag synchronization is achieved and the unknown parameters are identified by using the adaptive lag laws. Moreover, the scheme is analytical and is simple to implement in practice. The well-known fractional order chaotic L/i system is used to illustrate the validity of this theoretic method.

Adaptive synchronisation of fractional-order chaotic systems

A new stability theory of nonlinear dynamic systems is proposed, and a novel adaptive synchronisation method is presented for fractional-order chaotic and hyperchaotic systems based on the theory described in this paper. In comparison with previous methods, not only is the present control scheme simple but also it employs only one control strength, converges very fast, and it is also suitable for a large class of fractional-order chaotic and hyperchaotic systems. Moreover, this scheme is analytical and simple to implement in practice. Numerical and circuit simulations are used to validate and demonstrate the effectiveness of the method.

A single adaptive controller with one variable for synchronization of fractional-order chaotic systems

In this paper we investigate the synchronization of a class of three-dimensional fractional-order chaotic systems. Based on the Lyapunov stability theory and adaptive control technique, a single adaptive-feedback controller is developed to synchronize a class of fractional-order chaotic systems. The presented controller which only contains a single driving variable is simple both in design and in implementation. Numerical simulation and circuit experimental results for fractional-order chaotic system are provided to illustrate the effectiveness of the proposed scheme.

Chaos in fractional-order generalized Lorenz system and its synchronization circuit simulation

The chaotic behaviours of a fractional-order generalized Lorenz system and its synchronization are studied in this paper. A new electronic circuit unit to realize fractional-order operator is proposed. According to the circuit unit, an electronic circuit is designed to realize a 3.8-order generalized Lorenz chaotic system. Furthermore, synchronization between two fractional-order systems is achieved by utilizing a single-variable feedback method. Circuit experiment simulation results verify the effectiveness of the proposed scheme.

Photon-assisted and spin-dependent shot noise in magnetic-field tunable ZnSe/Zn1-xMnxSe structures

We have investigated the photon-assisted shot noise properties in the magnetic field tunable heterostructures. Transport properties of the model structure are strongly dependent on the oscillatory field and the magnetic field. In this structure,electrons can absorb or emit one or multi-photons to reach the quasi-bound state. As a result, the transmission properties are affected considerably by photon-assisted tunneling and these features cause the nontrivial variations in the shot noise and Fano factor. It is found that the shot noise becomes spin-dependent and can be modulated not only by the magnetic field, but also by the oscillatory field. Both the spin-up and spin-down components of the shot noise can be greatly suppressed by the magnetic field, and can also be drastically enhanced by the harmonically driven field. Furthermore,with increasing external magnetic field, it is important to note that the enhanced intensity is decreased, even suppressed.These results suggest another method to suppress the shot noise via modulating the oscillatory field at a diluted-magneticsemiconductors/semiconductor structure.

H_(2)S-releasing adhesive hydrogel as oral radioprotectant for gastrointestinal tract radioprotection

Radiation damage can cause a series of gastrointestinal(GI)tract diseases.The development of safe and effective GI tract radioprotectants still remains a great challenge clinically.Here,we firstly report an oral radioprotectant Gel@GYY that integrates a porous gelatin-based(Gel)hydrogel and a pH-responsive hydrogen sulfide(H2S)donor GYY4137(morpholin-4-ium 4 methoxyphenyl(morpholino)phosphinodithioate).Gel@GYY has a remarkable adhesion ability and long retention time,which not only enables responsive release of low-dose H2S in stomach and subsequently sustained release of H2S in the whole intestinal tract especially in the colon,but also ensures a close contact between H2S and GI tract.The released H2S can effectively scavenge free radicals induced by X-ray radiation,reduce lipid peroxidation level,repair DNA damage and recover vital superoxide dismutase and glutathione peroxidase activities.Meanwhile,the released H2S inhibits radiation-induced activation of nuclear factorκB(NF-κB),thus reducing inflammatory cytokines levels in GI tract.After treatment,Gel@GYY displays efficient excretion from mice body due to its biodegradability.This work provides a new insight for therapeutic application of intelligent H2S-releasing oral delivery system and potential alternative to clinical GI physical damage protectant.

Supramolecular assembly of Keggin polyoxomolybdate and 2,2'-bipyridine generated in situ from a decarboxylation coupling reaction

An assembly of Keggin polyoxomolybdate and organic substrate （Hbipy）3[PM01204o] （1, bipy = 2,2＇- bipyridine） was synthesized and characterized by elemental analysis, infrared spectrum, and single- crystal X-ray analysis. The ligand bipy of compound 1 was generated by a decarboxylation coupling reaction of H2pdc （H2pdc = pyridine-2,6-dicarboxylic acid） in situ under hydrothermal reaction conditions and the control experiments illustrate that La（NO3）3 or Ce（NO3）3, which does not appear in the final structure, is necessary for the decarboxylation coupling reaction. Moreover, compound 1 displays strong photoluminescence property in the solid state at room temperature.

Silver nanocubes monolayers as a SERS substrate for quantitative analysis

Surface-enhanced Raman scattering(SERS)is a powerful spectroscopic tool in quantitative analysis of molecules,where the substrate plays a critical role in determining the detection performance.Herein,a silver nanocubes/polyelectrolyte/gold film sandwich structure was prepared as a reproducible,highperformance SERS substrate by the wate r/oil inte rfacial assembly method.In addition to the hot spots on the nanocubes surface,the edge-to-edge interspace of the Ag nanocubes led to marked enhancement of the SERS intensity,with a limit of detection of 10~(11)mol/L and limit of quantitation of 10~(10)mol/L for crystal violet.When rhodamine 6 G and crystal violet were co-adsorbed on the Ag nanocube surfaces,the characteristic SERS peaks of the two molecules remained well resolved and separated,and the peak intensities varied with the respective concentration,which could be exploited for concurrent detection of dual molecules.Results from this work indicate that organized ensembles of Ag nanocubes can serve as effective SERS substrate can for sensitive analysis for complex molecular systems.

Mn^(2+)-doped ZrO_(2)@PDA nanocomposite for multimodal imaging-guided chemo-photothermal combination therapy

Developing low toxicity and multifunctional theranostic nanoplatform is the key for precise cancer diagnosis and treatment.Herein,an inorganic-organic hybrid nanocomposite is designed by modifying zirconium dioxide(ZrO_(2)) with polydopamine(PDA) followed by doping Mn^(2+) ions and functionalizing with Tween 20(Tween-ZrO_(2)@PDA-Mn2+) for multimodal imaging and chemo-photothermal combination therapy.The as-prepared nanocomposite exhibits good biocompatibility in vitro and in vivo.Specifically,it can be employed as a multifunctional platform not only for computed tomography(CT)imaging and T1-weighted magnetic resonance(MR) imaging,but also for efficient chemotherapeutic drug doxorubicin hydrochloride(DOX) loading.Importantly,because of the pronounced photothermal conversion performance and controllable DOX release ability triggered by the near-infrared(NIR)irradiation and acidic pH,the synergistic effect between photothermal the rapy and chemotherapy results in an enhanced cancer treatment efficacy in vivo.Our work provides a high-performance inorganicorganic hybrid nanotheranostic platform for chemo-photothermal cancer therapy guided by CT and MR imaging.