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In this paper, a new technology is proposed to research the problem of the synchronization transmission of spiral wave and turbulence between uncertain time-delay neuronal networks with different node numbers and topologies. In order to construct the Lyapunov–Krasovskii functional of the network, a special function is designed. According to our scheme, the uncertain time-delay neuronal network can transfer synchronously the spiral wave and turbulence, especially the chattering near the synchronization target can also be eliminated, which indicates that the synchronization performance of the network is more stable. At the same time, the recognition law of the network coupled matrix element is also designed to replace effectively the uncertain coupled matrix element in the network.

A new strategy is designed to research the synchronization transmission of laser pattern signals between uncertain networks constructed by Gibbs laser spatial expanded models. First, we introduce the output characteristics of the Gibbs laser spatial expanded model and show the typical spatiotemporal patterns. Furthermore, we select Gibbs laser spatial expanded models to constitute the laser networks and to realize the synchronization transmission of the laser signals between the networks. The synchronization strategy allows the existence of uncertain or unknown parameters in the network and these parameters can be replaced by the designed identification law. At the same time, the synchronization performance of the networks is not affected by the network topology and the number of nodes. Especially, the structure of the designed network controller is simple, which is very convenient for practical application.

Natural water evaporation (NWE) is spontaneous and ubiquitous process that absorbs ambient thermal energy. Scavenging ambient thermal energy into electricity by NWE provides a promising approach to supply power for self-powered and low-cost devices and systems. Suitable materials and techniques are required to use this ubiquitous natural process for electricity generation. Herein, a continuous NWE-driven flexible generator is fabricated by painting Ni-Al layered double hydroxide (LDH) on a polyethylene terephthalate substrate at room temperature. The generator operates through an NWE-driven gradient of water that flows across the naturally formed surface-charged nanochannels between Ni-Al LDH flakes; i.e., the streaming potential mechanism. The output electrical characteristics of the device can be controlled by adjusting the environmental moisture and wind velocity. Continuous electricity output with a comparatively high power density of 16.1 μW cm−3 is achieved from a generator. The generator can maintain a stable output power under deformation. The output power of the generator can be scaled up to continuously power integrated circuit devices such as a digital calculator. Given the easy fabrication process of this flexible NWE-driven generator using an environmentally friendly LDH and its continuous electricity output with relatively high power density, this generator represents an important step towards practical green ambient energy harvesting.

We investigate the cluster synchronization in uncertain network with nonidentical nodes based on adaptive pinning control. In this synchronization technology, the network can be arbitrarily divided into several clusters. And the network parameters can be uncertain and they follow a kind of the identification law. By utilizing pinning control strategy, cluster synchronization criterion for the uncertain network has been established. Finally, the numerical simulation is provided to prove the effectiveness of proposed pinning control strategy.

In this paper, the problem of exponential synchronisation between time-delay spatiotemporal network and target system is studied. Based on the Lyapunov stability principle, the Lyapunov–Krasovskii generic function with exponential form is designed, and the form of the synchronisation controller is determined, so that the exponential synchronisation is realised between the time-delay spatiotemporal network and the target system. In simulation, Fisher–Kolmogorov system is further selected as the network node to verify the rationality of synchronisation scheme. This technology fully considers the effect of time delay on network synchronisation performance, making the synchronisation scheme more practical. In addition, exponential synchronisation technology can effectively adjust the rate of network synchronisation.

Quantum systems can display the quantum chaos characteristics under non-rotating wave approximation. Because of the complex multi-body effect, the inevitability of coupling with the environment and the existence of uncertainty relation, some parameters in quantum system are often uncertain. In order to determine the properties of quantum system, we need to accurately measure any parameters in the system. In this work, we first analyse the characteristics of quantum bits interacting with a single-mode radiation field. On this basis, we design a unique technique to accurately measure the uncertain parameter in the quantum bits. Finally, we complete the synchronization transmission of signal in quantum bits based on the sliding mode control technology.

In this paper, the problem of finite-time synchronisation of uncertain delay spatiotemporal networks via unidirectional coupling technology is investigated. Based on Lyapunov theorem and finite-time stability theory, an effective finite-time synchronisation scheme is designed to achieve finite-time synchronisation between uncertain delay spatiotemporal networks, and adaptive estimations of coupling coefficient, unknown parameter and uncertain network topology are realised. Then, the Fisher–Kolmogorov spatiotemporal model is used as the state equation of the network node for numerical simulation. The simulation results show that the finite-time synchronisation scheme is effective.

In this work, the synchronization between uncertain time-delayed networks with multi-link and different topologies is investigated. We design the suitable identification laws to tackle the uncertain parameters in the drive and response networks. And we also design the adaptive laws to determine the configuration matrix elements of the networks. This synchronization strategy allows the driver and response networks to have different topologies. And it is unnecessary to solve the eigenvalues of the network node equations.

We investigate outer synchronization between uncertain networks with adaptive scaling function and different node numbers. In designed synchronization strategy, the drive and response networks may differ in the node numbers and the network topologies. Moreover, the adaptive scaling function can be replaced by the adaptive law. The uncertain adjustment parameter and the uncertain coupling matrix element are identified simultaneously in the process of synchronization. Finally, the numerical example is exploited to illustrate the effectiveness of the proposed synchronization criteria.

We concentrate on the synchronization problem of the uncertain time-delayed network with multi-link. In this work, we design a novel technology to obtain the network synchronization condition so that we do not need to solve the Jacobi matrices of the state equations at the network nodes. Moreover, the uncertain parameters in state equations at the network nodes can also be identified simultaneously in the process of synchronization. Finally, a numerical example is given to demonstrate the effectiveness of the proposed approach. Our results are suitable for the multi-link network with arbitrary topology. And the dynamical network with single-link can be considered as a special case of dynamical network with multi-link.

We research cluster synchronization transmissions of different external signals in discrete uncertain network. Based on the Lyapunov theorem, the network controller and the identification law of uncertain adjustment parameter are designed, and they are efficiently used to achieve the cluster synchronization and the identification of uncertain adjustment parameter. In our technical scheme, the network nodes in each cluster and the transmitted external signal can be different, and they allow the presence of uncertain parameters in the network. Especially, we are free to choose the clustering topologies, the cluster number and the node number in each cluster.

We research outer synchronization between uncertain time-varying networks with different node number. Based on the Lyapunov theorem, some new sufficient synchronization criteria are proposed. Further, we design the adaptive laws of the time-varying coupling matrix element and the adjustment parameter. And the designed controller can ensure that outer synchronization between uncertain time-varying networks with different node number can be achieved perfectly. At last, numerical examples are illustrated to demonstrate the efficiency of the proposed scheme.

A photo-detector with n-ZnO nano-arrays/p-NiO film structure was synthesized on flexible Ni foil substrate. In contrast to conventional detectors that detect only the photon energies greater than the band gap of working materials, the visible light with smaller photon energies (3.0 eV) than the band gap of both ZnO (3.3 eV) and NiO (3.7 eV) can be sensitively detected by this detector due to the spatially indirect type-II transition between ZnO nano-arrays and NiO film. The increase in output currents of the photo-detector with illumination density was observed at both forward and reverse bias, and it can be further enhanced by exerting external compressive strain along the c axis of ZnO nano-arrays by piezo-phototronic effect. A maximum enhancement of 1020% of the responsivity (R) was achieved under external compressive strain. The similar behaviors were demonstrated at four different excitation wavelengths (325, 365, 388 and 405 nm), providing compelling evidence that the responses performance of the photo-detector can be effectively enhanced using piezo-phototronic effect. Moreover, the piezo-phototronic effect enhanced performance can be well elucidated by the corresponding energy band diagram.

A series of Zn2GeO4:Tb3+ nanophosphors have been prepared by the high temperature solid state method. The XRD patterns of samples are basically consistent with Zn2GeO4 standard card and the influence of Tb3+ ion on the peak shift is discussed detailedly. The SEM results show that the average sizes of all nanophosphors, whether undoped or doped, are about 50 nm except that some particles in Zn2GeO4 nanophosphor doped with 0.7 mol% terbium take on the cubic structure and the maximum size are about 130 nm. Under 265 nm excitation, there exists a broad blue emission belonging to Zn2GeO4 host. Moreover, the intense photoluminescence peaks at 490, 550 nm and weak peaks at 585, 622 nm of Tb3+ ions are obtained, and optimum Tb3+ doping concentration is 0.7 mol%. The decay curves of host emissions with the varied Tb3+ concentrations are measured, and the mechanisms of photoluminescence and energy transfer from Zn2GeO4 host to Tb3+ ions are analyzed systematically.

We research synchronization of uncertain time-varying network based on sliding mode control technique. The sliding mode control technique is first modified so that it can be applied to network synchronization. Further, by choosing the appropriate sliding surface, the identification law of uncertain parameter, the adaptive law of the time-varying coupling matrix element and the control input of network are designed, it is sure that the uncertain time-varying network can synchronize effectively the synchronization target. At last, we perform some numerical simulations to demonstrate the effectiveness of the proposed results.

We propose a new technology for synchronization transmission of laser pattern signal within uncertain network with controllable topology. In synchronization process, the connection of dynamic network can vary at all time according to different demands. Especially, we construct the Lyapunov function of network through designing a special semi-positive definite function, and the synchronization transmission of laser pattern signal within uncertain network with controllable topology can be realized perfectly, which effectively avoids the complicated calculation for solving the second largest eignvalue of the coupling matrix of the dynamic network in order to obtain the network synchronization condition. At the same time, the uncertain parameters in dynamic equations belonging to network nodes can also be identified accurately via designing the identification laws of uncertain parameters. In addition, there are not any limitations for the synchronization target of network in the new technology, in other words, the target can either be a state variable signal of an arbitrary node within the network or an exterior signal.

We modify sliding mode control technique from the synchronization of a single dynamic system to the synchronization of complex network. Projective synchronization of uncertain scale-free network is investigated based on modified sliding mode control technique. Further, the sliding surfaces, the identification laws of uncertain parameters and the control inputs are designed, and the condition of realizing projective synchronization of uncertain scale-free network is obtained. Finally, the Logistic systems with chaotic behavior are taken as nodes to constitute the scale-free network and the synchronization target. The simulation results show that the synchronization mechanism is effective.

We consider the synchronization transmission problem of spiral wave and turbulence within the uncertain switching network. Through constructing reasonably the Lyapunov function of the network, the uncertain switching network not only can transfer synchronously the spiral wave and turbulence originated from the synchronization target, but also the chattering near the synchronization target can be eliminated, which indicates that the synchronization performance of the network is more stable. At the same time, the adaptive laws of the uncertain parameters are designed and the uncertain parameters in the switching network nodes are replaced effectively.

We propose a new technique for the cluster synchronization between uncertain networks with different dynamics. Based on the Lyapunov theorem and Lipschitz condition, the network controllers and the identification laws of uncertain parameters are designed, and they are efficiently used to achieve the cluster synchronization and the identification of uncertain parameters. Particularly in our work, the dynamics of nodes in different clusters can be different. And there are not any limitations for the division of the clusters, the number of nodes in each cluster and the connections between nodes.

The piezo-phototronic effect has drawn great interest recently due to its improvement of optoelectronic devices performance by effectively controlling the carrier generation, separation, transport, and/or recombination at the interface/junction of the p–n junction. In this study, a compact sensitivity controllable pressure sensor with the n -ZnO nano-arrays/ p -Cu 2 O film structure is synthesized on flexible Cu foil substrate, and the improved performance due to piezo-phototronic effect is characterized systematically. The heterostructure shows a nearly ideal rectifying behavior with substantial forward current of more than 1 mA (at 3 V) under pressure free and dark conditions, indicating excellent p - n junction was formed at the n -ZnO nano-arrays/ p -Cu 2 O film interface. The linear dependence of switch ratio ( SR ) ( I/I 0 ) on the applied pressure and response time of ~1 s were observed in the pressure sensor. The linear dependence can be further improved and a value up to 376% is reached by the illumination radiation of the 405 nm violet light emitting diodes (LEDs), which had been tactfully embedded within the device. The advantages of embedding LEDs in the sensor lie in reducing of device volume as well as preventing influence of environment light on the sensor performance. Furthermore, a substantial enhancement in the sensitivity ( I-I 0 /I 0 / ∆ P ) of the pressure sensor is achieved by adjusting the illumination intensity, which reaches 918% at the illumination intensity of 11.7 mW/cm 2 . The piezo-phototronic effect enhanced performance can be well elucidated by the corresponding energy band diagram. Our achievement provides a very promising method to improve the SR and sensitivity controllability of pressure sensor using piezo-phototronic effect.

In this work, we design a novel synchronization technique to realize the synchronization of the network group which is constituted by some uncertain discrete networks with diverse structures. Based on Lyapunov theorem, the selection principle of the control inputs and identification law of uncertain parameters in networks are determined, and the synchronization conditions of network group are obtained. Finally, numerical simulations using one-dimensional convective equations with spatiotemporal chaos behaviors illustrate the performance of the synchronization scheme. The research results show that our synchronization technique can be suitable for the network connecting arbitrarily, and not only the network number but also node number in each network can also be chosen freely.

In this paper, we propose a novel synchronization technique to investigate the projective synchronization of a class of uncertain network. First, the sliding mode control technique is modified. Then, the sliding surface between each node of the network and the synchronization target and the control input of the network are designed, and the uncertain parameter in the network can be effectively identified using the identification law of the uncertain parameter. In the end, a numerical example is given to illustrate the effectiveness of the synchronization technique proposed in our work. Copyright © 2016 John Wiley & Sons, Ltd.

Some typical dual-ring erbium-doped fiber lasers with hyperchaos behaviors are taken as nodes to construct two kinds of small-world networks—NW and WS networks. Based on Lyapunov stability theorem, the appropriate controllers are designed and the outer synchronization between the small-world networks with diverse structures and different node numbers is further investigated. The simulation results show that the perfect synchronization between the complex small-world networks is realized, which is of potential application for all optical communication network.

We design a novel synchronization technique to research the synchronization of network group constituted of uncertain networks with different structures. Based on Lyapunov theorem, the selection principles of the control inputs and the parameter identification laws of the networks are determined, and synchronization conditions of the network group are obtained. Some numerical simulations are provided to verify the correctness and effectiveness of the synchronization technique. We find that the network number, the number of network nodes and network connections indeed will not affect the stability of synchronization of network group.

We propose a new technology to synchronize the uncertain dynamical network with the switching topology. In this new technology, we construct the Lyapunov function of network through designing a special function to obtain the network synchronization condition, which effectively avoids the complicated calculations for solving the second largest eigenvalue of the coupling matrix of the dynamical network. At the same time, the uncertain parameters in state equations at network nodes can also be identified accurately by the designed identification laws of uncertain parameters. Our results are universal without assumption about the symmetry of the coupling matrix in network, which can be widely used to research various topologies, no matter whether they are undirected or directed, weighted or unweighted, time-invariant or switching. And there are not any limitations for the synchronization target of network.

Self-assembled mono- and bi-nuclear complexes of Cd(II) (1), Co(II) (2), Zn(II) (3), Ni(II) (4) and Cu(II) (5) were synthesized via the reaction of 5-methyl-1-(4-carboxylphenyl)-1H-1,2,3-triazole-4-carboxylic acid (H2L) and the corresponding metal salt under hydrothermal conditions. All complexes were characterized using elemental analysis, IR spectroscopy, UV-vis spectroscopy, PXRD analysis, thermogravimetry and single-crystal X-ray diffraction. Structural analyses show that the H2L ligand exhibits diverse coordination modes: μ2-η1O-η1O-η1O-η1N for 1, μ2-η1O-η1O-η1N for 2–4 and μ3-η1O-η1O-η1N-η1O for 5. Based on the various structures and the luminescent response of xanthine (3,7-dihydro-purine-2,6-dione), a new experiment for exploring the interaction between transition metal complexes and luminescent xanthine was performed for the first time. The results show that the luminescence response of xanthine depends on the concentration of metal complex.

We have prepared a flexible natural water evaporation (NWE) driven silicon carbide (SiC) nano-generator on the polyethylene terephthalate (PET) substrate. When the water driven by evaporation flows through the surface of SiC material, the solid-liquid interaction between water and SiC will induce continuous electricity output. The detail mechanism of the solid-liquid interaction is discussed in this paper. The open circuit voltage (Voc) and short circuit current (Isc) are nearly proportional to the evaporation height and evaporation width of the generator, respectively. Moreover, the Voc and Isc of the generator can be finely controlled by regulating the relative humidity, air flow and photo-thermal energy assistant technique.

The CaSrSiO4 nanophosphor-doped 0.7 mol% Tb3+ ions have been prepared by the high-temperature sintering method. XRD pattern is consistent with the standard card of CaSrSiO4 host, and the average particle size of CaSrSiO4:0.7Tb is about 50 nm. There exist intense green (544, 552 nm) and weak blue (485, 488 nm), yellow (588 nm), and red (625 nm) emissions under the excitation of 325 nm He–Cd laser, corresponding, respectively, to the transitions of Tb3+ ions from 5D4 and its splitting to 7F5,4,6,3,2 energy levels. The low-temperature photoluminescence characteristics of the sample are measured in the range of 290–10 K. The relationship between fluorescence intensity ratio and temperature is FIR = 0.895 + 0.469exp(− 145.8/T) and the maximum value of sensitivity is 17.6 × 10− 4 K− 1 at 70 K, indicating that CaSrSiO4:Tb3+ nanophosphor is a promising sensing material for low-temperature measurement.

A new synchronization technique of inner and outer couplings is proposed in this work to investigate the synchronization of network group. Some Haken–Lorenz lasers with chaos behaviors are taken as the nodes to construct a few nearest neighbor complex networks and those sub-networks are also connected to form a network group. The effective node controllers are designed based on Lyapunov function and the complete synchronization among the sub-networks is realized perfectly under inner and outer couplings. The work is of potential applications in the cooperation output of lasers and the communication network.