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Poly(styrene-b-butadiene-b-styrene) (SBS) triblock copolymer templates which present an in-plane cylinder pattern have been prepared by controlling the solvent evaporation rate. Then silver clusters have been deposited onto the SBS copolymer templates by low energy clusters beam deposition (LECBD) apparatus. The morphology of the sample has been characterized by AFM with tapping-mode. It is shown that silver clusters aggregate into nanoparticle chains onto the template at about 100% coverage. Optical absorption spectra reveal that the surface plasmon resonance (SPR) of silver nanoparticle chains occurs at 550 nm, being a red shift of -85 nm compared to silver nanoclusters deposited on the fused quartz substrate, and the width of SPR peak broadens.

This paper presents some interesting image processing applications with the mutually coupled two-layer Cellular Neural Networks (CNNs). We found that the two-layer CNNs are very useful compared to single layer CNNs in some applications such as center point detection, skeletonization, and so on. We also focus our discussions on both their transients and operations. In addition, the stability of the two-layer CNNs with mutually coupled symmetric templates is also discussed based on those of decoupling CNN technique.

Visual illusion is the fallacious perception of reality or some actually existing object. In this paper, we imitate the mechanism of Ehrenstein illusion, neon color spreading illusion, watercolor illusion, Kanizsa illusion, shifted edges illusion, and hybrid image illusion using the Open Source Computer Vision Library (OpenCV). We also imitate these illusions using Cellular Neural Networks (CNNs). These imitations suggest that some illusions are processed by high-level brain functions. We next apply the morphological gradient operation to anomalous motion illusions. The processed images are classified into two kinds of images, which correspond to the central drift illusion and the peripheral drift illusion, respectively. It demonstrates that the contrast of the colors plays an important role in the anomalous motion illusion. We also imitate the anomalous motion illusions using both OpenCV and CNN. These imitations suggest that some visual illusions may be processed by the illusory movement of animations.

We present a simplified treatment of templates used to summarize the topological properties of chaotic attractors bounded by a genus-1 torus. The reduction is based on determinism and flow continuity, which impose tight relations between torsions of each branch, rotations between pairs of branches and the order in which they join at the branch line. This way, the number of integer parameters necessary to characterize a template can be reduced. Apart from the purely theoretical interest, the new treatment simplifies the procedure for template determination starting from a time series, with a consequential save in computation time.

The topological analysis of chaotic attractor by means of template is rather well established for simple attractors as solution to the Rössler system. Lorenz-like attractors are already slightly more complicated because they are bounded by a genus-3 bounding torus, implying the necessity to use a two-component Poincaré section. In this paper, we enriched the concept of linking matrix to correctly describe an algebraic template for an attractor with (g - 1) components of Poincaré section and whose bounding torus has g interior holes aligned. An example with g = 5 — a multispiral attractor — is explicitly treated.

A chaotic attractor solution of the Lorenz system [Lorenz, 1963] with foliated structure is topologically characterized. Its template permits to both summarize the organization of its periodic orbits and detail the topology of the solution as a branched manifold. A template of an attractor solution of the Chen system [Chen & Ueta, 1999] with a similar foliated structure is also established.

The purpose of this study was to demonstrate the accuracy of a novel, surgically useful guide that could place a drill or pin within the femoral head. The radiolucent guide for attachment to the lateral femoral cortex was tested for reproducibility on cadaveric specimens simulating a surgical procedure. The guide allows selection of the three-degree freedom angle of insertion of a drill or pin via two circular channels allowing anterior–posterior or superior–inferior adjustment. The guide can accurately place a pin tip within 2.5–3.8 mm of a desired location. We conclude this guide could be used to accurately place a fibular graft in an osteonecrotic lesion, or place pins or nails during many different surgical procedures such as fractures or slipped capital femoral epiphysis.

Ordered Au/Ni multilayer nanowire arrays have been fabricated into the pores of anodic aluminum oxide (AAO) templates by pulse DC electrodeposition. Structural parameters, such as nanowire length and layer thickness can be controlled by changing the deposition time and the pulse width. The magnetic measurement results indicate that these Au/Ni multilayer nanowire arrays have small coercivity and perpendicular magnetic anisotropy, which the easy axis is parallel to the nanowires. These Au/Ni multilayer structures are expected to be found potential applications in AC inductors or magnetic shielding.

Coping with geometrical attacks in transform domain is crucial when we design a robust image watermarking scheme. In this paper, a novel contourlet-domain image watermarking scheme, which is robust to common signal processing and geometrical attacks, is proposed. First, the region with maximum energy in the directional subbands is considered for watermarking, i.e. the watermark can be embedded into the significant region as well as highly textured region of the host image. Then, for each coefficient of the selected subband, the strength factor was adaptively adjusted in terms of the energy of its parent and neighbor coefficients. Consequently, the tradeoff between the transparency and robustness of watermark can be achieved. Furthermore, the robust feature points, which can survive various signal processing and affine transformation, are extracted by using the Harris–Laplace detector. In watermark detection, the geometrical distortion of image is identified by using the feature template constructed during embedding phase, i.e. watermark resynchronization is performed. Experimental results show that the proposed watermark scheme is invisible and robust against common signal processing such as median filtering, sharpening, noise adding and JPEG compression, etc and geometrical attacks such as rotation, translation, scaling, row or column removal, shearing and local random bend, etc.

Current tendency of electromyography (EMG)-based prosthetic hand is to enable the user to perform complex grasps or manipulations with natural muscle movements. In this paper, empirical copula-based templates; including the unified motion template and the state-based motion template, are introduced to identify the naturally contracted surface EMG (sEMG) patterns for hand motion recognition. The unified motion template utilizes a dependence structure as a motion template, which includes one-to-one correlations of the SEMG feature channels with all the sampling points, while the state-based motion template divides the sampling points into different states and takes the union of the dependence structures of the different states. Comparison results have demonstrated that the proposed Empirical Copula-based methods can successfully classify different hand motions from different subjects with better recognition rates than Gaussian mixture models (GMMs). In addition, the state-based motion template has a better performance than the unified motion template especially for the complex hand motions.

Porous poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) membranes were successfully prepared using dibutyl phthalate (DBP), polyvinylpyrrolidone (PVP-K30), polyethylene glycol 200 (PEG200) as templates. SEM was used to examine the morphology of the PVDF-HFP porous membranes. It was found that these membranes have an asymmetric structure and the blends of PVDF-HFP/DBP formed nanoporous membranes, whereas the blends of PVDF-HFP/PVP-K30 formed "sponge-like" and microporous membranes. Moreover, the average pore size and porosity was about 0.3 μm and 48.7%, respectively. The crystallinity, thermal stability and mechanical strength of membranes were characterized by XRD, DSC, TGA and stress-strain tests. The results showed that the membranes are α crystals with excellent thermal stability. It was an effective way to regulate pore size and morphology of the PVDF-HFP membranes.

A novel method to prepare crosslinked polyethyleneimine (CPEI) hollow nanospheres was reported. Uniform silica nanospheres were used as templates, 3-aminopropyl trimethoxysilane (APS) was immobilized on the surface of silica nanospheres as couple agent. Aziridine was initiated ring-opening polymerization with the amino groups in APS to form polyethyleneimine (PEI) shell layer. 1,4-Butanediol diacrylate was utilized to crosslink PEI polymeric shell. The silica nanospheres in core were etched by hydrofluoric acid to obtain hollow CPEI nanospheres. The hollow nanospheres were characterized by X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA).

The development of novel nanomaterials has been in the fore front of research in recent years due to the unusually outstanding properties of such materials. Metallophthalocyanines are well known to be of very good use in a wide range of applications. Nanomaterials based on this class of compounds could potentially have better qualities than the "parent" molecules. The electrochemical synthesis of cobalt phthalocyanine nanowires and the characterization using scanning electron microscope are presented. This is the first step towards a move to harnessing the potential of this class of nanomaterials for a wide range of new possible applications.

Porphyrins and metalloporphyrins are one of the most widely studied platforms for the construction of supramolecular structures. These compounds have an extended aromatic system that allows $\pi$–$\pi$ stacking interactions which, together with hydrogen bonds, electrostatic forces and the formation of inter-metallic complexes arising from peripheral groups, offer a versatile platform to control the self-assembly mechanism. In this work, we present the study of nanostructures formed by self-assembly of the water-soluble porphyrins meso-tetra($N$-methyl-4-pyridyl)porphyrin (TMPyP) and meso-tetra(4-sulfonatophenyl)porphyrin (TPPS) in the presence of hard nanotemplates. Different nanoparticles (silica, gold, and polystyrene), concentrations and synthetic procedures were explored. The obtained materials were characterized by SEM and AFM microscopies, UV-vis absorption spectroscopy and dynamic light scattering measurements. A clear modification of the SiO₂ NP surface roughness using one-pot synthesis was observed. The results were variable depending on the porphyrin–surface interactions and concentrations used. At lower porphyrin concentrations, a shift of the Soret band was observed, while at higher concentrations, free NS were formed. This reflects a competition between surface and solution directed self-assembly.

The copper nanoparticle chains have been synthesized through a self-assembly process with sodium polymethacylic acid as the template. The resulted nanoparticle chains were 0.8–1.5 μm long, and the composed nanoparticles were about 30 nm in diameter. The self-assembly formation mechanism has been proposed.

The conversion from one assembly structure to other composite assembly structures is valuable to both theoretical research and actual application in the nano/micromaterials science. In this paper, firstly, the flower-like calcium oxalate assembly structure was synthesized using a supramolecule template; then, through a facile process, the calcium oxalate was converted to a sphere-cluster-like core/shell CaC₂O₄/CaWO₄ nanocomposite assembly structure. The converted product remained the basic structure of original product, and possessed some new optical properties such as fluorescence, etc.

In the present study, Ni/Fe nanoparticles were synthesized using bound micelles as a template and 3, 3^′, 4, 4^′-tetrachlorobiphenyl (PCB77) as the target contaminant. The dual bound micelles, which are composed of polyvinylpyrrolidone (PVP) and sodium dodecyl sulfate (SDS), were found to be superior to single-component templates for the dispersion of metallic ions and thus directed the synthesis of Ni/Fe nanoparticles with improved properties. After characterization of the different nanoparticles, it was found that the sustained effectiveness of PVP–SDS bound micelles afforded specialized structures with two gradations of Ni/Fe nanoparticles, correlating to more active sites and higher activity. The improved activity of the Ni/Fe nanoparticles was finally exhibited by the higher ratio (99.3% in 72 h) and efficiency (k_obs of 0.0674 h^-1) of PCB77 removal. Herein, the utilization of PVP–SDS bound micelles is proposed as a template for the improvement of iron-based nanoparticles and correlated research.

Hydroxyapatite (HAP) with multiform morphologies, such as hollow dandelion-like bundles and nanoparticles with a diameter of 50nm, was prepared using natural rosin-based surfactant dehydroabietyl phosphate diester (DDPD) as phosphorus source, crystal growth control agent, and template simultaneously by a facile hydrothermal method. Samples were obtained and characterized by X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Results showed that DDPD and pH value of solution were the key factors for the morphology of HAP. Hollow dandelion-like bundles HAP, containing the Ca-monodehydroabietyl phosphate (PM-Ca) organic metal compounds, were formed at pH$=$3 without acid-base regulation, and nanoparticles were obtained at pH$=$12. SEM exhibited that the hollow dandelion-like bundles HAP are of 10$\mu$m (outer) and 1$\mu$m (inner) diameter, respectively. Cell viabilities are above 95% when the cells are co-cultured with all HAP samples at concentrations in the range of 250–1000$\mu$g/ml. It indicated that the prepared HAP with PM-Ca has a good cytocompatibility without apparent toxicity. Finally, the possible formation mechanism of the HAP microstructures was discussed in detail.

Developing nonmetal-doped mesoporous TiO₂ is highly attractive for preparing semiconductor visible photocatalyst with high activities. Here, we prepare N/F co-doped mesoporous TiO₂ with high vis-photocatalytic activities by a simple liquid phase deposition process followed by annealing in air using C${}_{16}$TAB as a bi-functional template (forming mesoporous and providing dopants). N₂ adsorption isotherms, low-angle X-ray diffraction (XRD) and transmission electron microscopy (TEM) indicate the formation of wormhole-like mesoporous structure. Wide-angle XRD and high-resolution TEM demonstrate the presence of anatase TiO₂ mesopore wall. XPS analyses reveal that N is doped into TiO₂ lattice in the forms of substitutional and interstitial N species, and that F is doped into the TiO₂ lattice in the form of interstitial F. The mesopore-forming and doping mechanisms are thoroughly discussed based on the bi-function of C${}_{16}$TAB template. Mesoporous structure results in a high BET surface area of TiO₂. High-concentration nitrogen species in anatase lattice and mesoporous structure remarkably increase the visible absorption of TiO₂. As a result, the reaction rate constant of MB degradation catalyzed by N/F co-doped mesoporous TiO₂ photocatalysts is about 7 times that by P25.

Highly ordered mesoporous iron oxide (α-Fe₂O₃) material has been successfully obtained from mesoporous silica template, KIT-6 (3-D Cubic Ia3d symmetry), through nano-replication method. The mesoporous α-Fe₂O₃ material thus obtained exhibits well-defined mesopores (2.7 nm in diameter), high surface area (148 m²/g), high pore volume (0.47 cm³/g) and crystalline frameworks. The morphology of the mesoporous α-Fe₂O₃ material is very uniform in spherical shape of which the average particle size is about 100 nm in diameter.