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Highly (001)-textured antimony telluride films were fabricated using molecular beam epitaxy (MBE) on Si (111) substrate at 280 °C. X-ray diffraction analysis implying the samples have good crystalline quality, simultaneously, the grain sizes coarsening with increasing thickness. The results of Hall coefficient measurement demonstrated that the carrier concentration and mobility are strongly affected by grain boundaries and microcrystalline internal defects. It was found that the grain boundaries play a primary factor influencing the carrier concentration in thinner film. At room temperature, the results in a maximum mobility value of 305 cm²=Vs for 121-nm-thick film, and the electrical conductivity increased from 425.7 S/cm to 1036 S/cm as the thickness varied from 28 nm to 121 nm. In the range of room temperature to 150 °C, the resistivity almost linearly increased with increasing temperature. This may be explained by low concentration of impurities or defects and shallow impurity band. For difference thickness films, temperature coefficients of resistivity are substantially equal, and the values are about 3~4 µΩ ⋅ cm=K. [ABSTRACT FROM AUTHOR]

In this paper, we illuminated the observation of asymmetric ferroelectric switching phenomena in fatigued P(VDF-TrFE) copolymer films. Two types of asymmetric switching were observed: one was the occurrence of switching dual peaks obtained from films with asymmetric electrode structure and the other was the jump of remanent polarization during fatigue process, as was obtained mostly from films with asymmetric electrodes and occasionally from films with symmetric electrodes. No evidence indicated the dependence between the switching dual peaks and the jump of remanent polarization. The possible mechanism of such asymmetric phenomena was also discussed. [ABSTRACT FROM AUTHOR]

This letter studies the multistability analysis of delayed recurrent neural networks with Mexican hat activation function. Some sufficient conditions are obtained to ensure that an n-dimensional recurrent neural network can have 3k15k2 equilibrium points with 0 ≤ k1 + k2≤ n, and2k13k2 of them are locally exponentially stable. Furthermore, the attraction basins of these stable equilibrium points are estimated. We show that the attraction basins of these stable equilibrium points can be larger than their originally partitioned subsets. The results of this letter improve and extend the existing stability results in the literature. Finally, a numerical example containing different cases is given to illustrate the theoretical results. [ABSTRACT FROM AUTHOR]

In this work, gold nanoparticles (Au NPs) were distributed on an n-Ge substrate using the colloidal NP deposition method to form Au NP/Ge Schottky diodes (SDs), and the current transport properties of these nano-SDs were studied. The current density-voltage (J-V) characteristics were measured on each nanometer-sized Au particle using a conducting atomic force microscope (C-AFM). These Au NP/Ge diodes showed a rectifying behavior. According to the thermionic emission (TE) model, the effective Schottky barrier height (SBH) and ideality factors n were obtained. The SBH for the Au NP/Ge diodes ranges from 0.22 to 0.30 eV and the ideality factor ranges from 3.8 to 8.6. The current density and the barrier height increase while the ideality factor decreases with increasing Au NP diameters. This indicates that the tunneling effect is enhanced because of the narrowed depletion width and decreased size of the Au NP/Ge SDs. To compare the electrical behavior with Au NP/Ge diodes, the Au thin film/Ge diodes were also prepared and their SBHs were much larger because of the image-charge lowering effect and the tunneling effect in Au NP/Ge diodes. [ABSTRACT FROM AUTHOR]

Twenty arylsulfonamide derivatives containing 2-arylamino-4(3H)-quinazolinone were synthesized and evaluated for their bioactivities. 4-Fluoro- N-(2-(4-oxo-2-(4-(trifluoromethoxy)phenyl)amino)quinazolin-3(4H)-yl)ethyl benzenesulfonamide, showed excellent activity both against Ralstonia solanacearum and Gibberella zeae with the inhibition rates of 100% (200 mg/L) and 95% (100 mg/L), and 69% (50 mg/L), respectively, exceeding that of the assigned commercial bactericide (thiodiazole-copper) and fungicide (hymexazol). The preliminary structure activity relationships (SAR) showed that both benzene rings of arylamino and arylsulfonamido moieties containing electron-withdrawing substitutes may be preferable for improving the bioactivity of target compounds. [ABSTRACT FROM AUTHOR]

Recent research in memristor-CMOS neuromorphic learning systems has led to the practical realization of neuro-inspired learning architectures. At present, the deep understanding of nonlinear dynamical mechanisms governing memristive neural systems is still an open issue. In this paper, the global exponential stability problem is investigated for a class of memristive neural systems with time-varying delays. By employing comparison principle, some novel global exponential stability results are derived. These stability conditions also improve upon some existing results. In addition, the obtained results are convenient to estimate the exponential convergence rate. These theoretical studies are very useful in analyzing the composite behavior of complex memristor circuits. [ABSTRACT FROM AUTHOR]

This paper presents a design method for synthesizing associative memories based on discrete-time recurrent neural networks. The proposed procedure enables both hetero- and auto- associative memories to be synthesized with high storage capacity and assured global asymptotic stability. The stored patterns are retrieved by feeding probes via external inputs rather than initial conditions. As typical representatives, discrete-time cellular neural networks (CNNs) designed with space-invariant cloning templates are examined in detail. In particular, it is shown that procedure herein can determine the input matrix of any CNN based on a space-invariant cloning template which involves only a few design parameters. Two specific examples and many experimental results are included to demonstrate the characteristics and performance of the designed associative memories. [ABSTRACT FROM AUTHOR]

In this letter, some sufficient conditions are obtained to guarantee recurrent neural networks with linear saturation activation functions, and time-varying delays have multiequilibria located in the saturation region and the boundaries of the saturation region. These results on pattern characterization are used to analyze and design autoassociative memories, which are directly based on the parameters of the neural networks. Moreover, a formula for the numbers of spurious equilibria is also derived. Four design procedures for recurrent neural networks with linear saturation activation functions and time-varying delays are developed based on stability results. Two of these procedures allow the neural network to be capable of learning and forgetting. Finally, simulation results demonstrate the validity and characteristics of the proposed approach. [ABSTRACT FROM AUTHOR]

In this paper, the multiperiodicity of a general class of discrete-time delayed neural networks (DTDNNs) is formulated and studied. Several sufficient conditions are obtained to ensure n-neuron DTDNNs can have 2n periodic orbits and these periodic orbits are locally attractive. In addition, we give the conditions for a periodic orbit to be locally or globally attractive when the periodic orbit locates in a designated region. As two typical representatives, the Hopfield neural network and the cellular neural network are examined in detail. These conditions improve and extend the existing stability results in the literature. Simulations results are also discussed in three illustrative examples. [ABSTRACT FROM AUTHOR]

This paper presents new theoretical results on global exponential stability of recurrent neural networks with bounded activation functions and time-varying delays. The stability conditions depend on external inputs, connection weights, and time delays of recurrent neural networks. Using these results, the global exponential stability of recurrent neural networks can be derived, and the estimated location of the equilibrium point can be obtained. As typical representatives, the Hopfield neural network (HNN) and the cellular neural network (CNN) are examined in detail. [ABSTRACT FROM AUTHOR]

We show that an n-neuron cellular neural network with time-varying delay can have 2n periodic orbits located in saturation regions and these periodic orbits are locally exponentially attractive. In addition, we give some conditions for ascertaining periodic orbits to be locally or globally exponentially attractive and allow them to locate in any designated region. As a special case of exponential periodicity, exponential stability of delayed cellular neural networks is also characterized. These conditions improve and extend the existing results in the literature. To illustrate and compare the results, simulation results are discussed in three numerical examples. [ABSTRACT FROM AUTHOR]

The Lagrangian formalism defined by Scherpen et al.for (switching) electrical circuits, is adapted to the Lagrangian formalism defined on Lie algebroids. This allows us to define regular Lagrangians and consequently, well-defined Hamiltonian descriptions of arbitrary LC networks. The relation with other Hamiltonian approaches is also analyzed and interpreted. [ABSTRACT FROM AUTHOR]

In this work, we mainly characterize stochastic bifurcations and tipping phenomena of insect outbreak dynamical systems driven by α-stable Lévy processes. In one-dimensional insect outbreak model, we find the fixed points representing refuge and outbreak from the bifurcation curves, and carry out a sensitivity analysis with respect to small changes in the model parameters, the stability index and the noise intensity. We perform the numerical simulations of dynamical trajectories using Monte Carlo methods, which contribute to looking at stochastic hysteresis phenomenon. As for two-dimensional insect outbreak system, we identify the global stability properties of fixed points and express the probability density function by the stationary solution of the nonlocal Fokker-Planck equation. Through numerical modelling, the phase portrait makes it possible to detect critical transitions among the stable states. It is then worth describing stochastic bifurcation associated with tipping points induced by noise through a careful examination of the dynamical paths of the insect outbreak system with external forcing. The results give new insight into the sensitivity of ecosystems to realistic environmental changes represented by stochastic perturbations. [ABSTRACT FROM AUTHOR]

Molybdenum (Mo) isotope ratios provide a potential means of tracing material recycling involved in subduction zone processes. However, the geochemical behavior of Mo in subducted oceanic crust remains enigmatic. We analyzed Mo isotope ratios of arc and back-arc basin lavas from the Mariana subduction zone (western Pacific Ocean), combining newly obtained element and Sr-Nd-Pb-Li isotope data to investigate subduction zone geochemical processes involving Mo. The Mo isotope ratios (δ98/95MoNIST3134; U.S. National Institute of Standards and Technology [NIST] Mo standard) of the volcanic rocks showed clear across-arc variations, decreasing with increasing depth to the Wadati-Benioff zone. The high δ98/95Mo values in the Mariana Islands (-0.18‰ to +0.38‰) correspond to high 87Sr/86Sr, low 143Nd/144Nd, and radiogenic Pb isotope ratios, suggesting that altered upper oceanic crust played an important role in the magma source. The low δ98/95Mo values in the Central Mariana Trough (-0.65‰ to -0.17‰) with mantle-like Sr-Nd-Pb but slightly low δ7Li values provide direct evidence for the contribution of deep recycled oceanic crust to the magma source of the back-arc basin lavas. The isotopically light Mo magmas originated by partial melting of a residual subducted slab (eclogite) after high degrees of dehydration and then penetrated into the back-arc mantle. This interpretation provides a new perspective with which to investigate the deep recycling of subducted oceanic lithosphere and associated magma petrogenesis. [ABSTRACT FROM AUTHOR]

An introduction to the journal is presented in which the editor discusses a study on particle swarm optimization with diversive curiosity, article on a proposed novel intelligent identification method, and a discussion on the structure of fault information fusion system.

The community structure and vertical distribution of prokaryotes in a deep-sea (ca. 3,191 m) cold sediment sample (ca. 43 cm long) collected at the East Pacific Rise (EPR) ∼13°N were studied with 16SrDNA-based molecular analyses. Total community DNA was extracted from each of four discrete layers EPRDS-1, -2, -3 and -4 (from top to bottom) and 16S rDNA were amplified by PCR. Cluster analysis of DGGE profiles revealed that the bacterial communities shifted sharply between EPRDS-1 and EPRDS-2 in similarity coefficient at merely 49%. Twenty-three sequences retrieved from DGGE bands fell into 11 groups based on BLAST and bootstrap analysis. The dominant groups in the bacterial communities were Chloroflexi, Gamma proteobacteria, Actinobacterium and unidentified bacteria, with their corresponding percentages varying along discrete layers. Pairwise Fst ( F-statistics) values between the archaeal clone libraries indicated that the archaeal communities changed distinctly between EPRDS-2 and EPRDS-3. Sequences from the archaeal libraries were divided to eight groups. Crenarchaea Marine Group I (MGI) was prevalent in EPRDS-1 at 83%, while Uncultured Crenarchaea group II B (UCII B) abounded in EPRDS-4 at 61%. Our results revealed that the vertically stratified distribution of prokaryotic communities might be in response to the geochemical settings and suggested that the sampling area was influenced by hydrothermalism. The copresence of members related to hydrothermalism and cold deep-sea environments in the microbial community indicated that the area might be a transitional region from hydrothermal vents to cold deep-sea sediments. [ABSTRACT FROM AUTHOR]