Twinning‐, Polytypism‐, and Polarity‐Induced Morphological Modulation in Nonplanar Nanostructures with van der Waals Epitaxy

Twinning, polytypism, and polarity are important aspects in nanostructural growth since their presence can affect various properties of the as‐grown products. The morphology of nanostructures grown via van der Waals epitaxy is shown to be strongly influenced by the twinning density and the presence of polytypism within the nanostructures, while the growth direction is driven by the compound polarity. With ZnTe as the model material, vertically aligned nanorods are successfully produced with variable cross‐section and branched crystals (tripods and tetrapods) on only a single type of substrate. Van der Waals epitaxy contributes by relaxing the lattice‐mismatch requirements for epitaxial growth and by enabling a variety of crystal planes in the initial stages of the growth to be interfaced to the substrate, regardless of the polarity of the epitaxial material. These results may provide more flexibility in tuning rationally the morphology of epitaxial nanostructures into other shapes with higher complexity by routine adjustment of growth environment.     

Analysis of phytohormones and phosphate solubilization in Photorhabdus spp.

Bacteria of the genus Photorhabdus are nematodes (Heterorhabditidae) symbiont and highly entomopathogenic in nature. Present study was concerned to investigate the effects of Photorhabdus temperata M1021 and Photorhabdus luminescens TT01 on plant morphology and physiology (‘Dongjin-beyo’ and ‘waitoc’). A significant (p<0.05) increase in the plant growth attributes including total plant length, root length, biomass, and chlorophyll contents were observed after treatment with culture extracts. Moreover indole-3-acetic acid (IAA) production by respective bacteria was confirmed by GCMS analysis. IAA production through tryptophan independent pathway was confirmed in P. temperata M1021 and P. luminescens TT01. Phosphate solubilization capability was also investigated by growing them on pikovskaya (PVK) agar as well as on PVK liquid medium with pH 7 at 28±2°C for 14 days. IAA production and phosphate solubilization capability of these bacteria could be the potential factors for plant growth promotion.     

A Filter Bank Based Approach for Rotation Invariant Fingerprint Recognition

This paper presents a systematic approach for image-based fingerprint recognition. The proposed method first enhances an input fingerprint image using a contextual filtering based method in the frequency domain. Complex filters are used for the detection of the core point, and a region of interest (ROI) of a predefined size centered at the detected core point is extracted. The resulting ROI is rotated based on the angle of the detected core point to ensure rotation invariance. Subsequently, the proposed system extracts the average absolute deviation (AAD) from the outputs of a Gabor filter bank. To reduce the dimensionality of the extracted features whilst generating more discriminatory representation, this paper compares the unsupervised Principal Component Analysis (PCA) and the supervised Linear Discriminant Analysis (LDA) methods for dimensionality reduction. User-specific thresholding schemes are investigated to improve the verification performance. The effectiveness of the proposed method is demonstrated through extensive experimentation on the FVC2002 set_a public database, in both identification and verification scenarios.     

Vibration characteristics of FGM circular cylindrical shells using wave propagation approach

In this paper, the wave propagation approach is employed to study the vibration characteristics of functionally graded material circular cylindrical shells. Axial modal dependence is approximated by exponential functions. This is a very simple and easily applicable technique. This avoids a large amount of algebraic manipulations. A theoretical analysis of shell natural frequencies are conducted for various boundary conditions. Validity and accuracy of the present method are confirmed by comparing the present results with those available in the literature. A good agreement is observed between the two sets of the results.     

Prediction of in-service microstructural degradation of A106 steel using eddy current technique

In-service microstructural degradation of ASTM A106 steel occurs by the spheroidising and coarsening of pearlite. The specimens of the A106 have been exposed at 710 °C for different durations to simulate service conditions. The resultant pearlite coarsening was evaluated by measuring eddy current inductive reactance and resistance; phase angles were measured using these values and compared with results of optical microscopy, image analysis and resistivity measurements. It was observed that the eddy current phase angle has a linear relation with pearlite variations. It can further be used for in-situ eddy current evaluation of microstructural degradation of pipes or steel vessels. A mathematical model has been proposed to assist such field investigations.     

Intermediate state of hexagonal close-packed structure to face-centered cubic structure transformation:Direct evidence for basal-type face-centered cubic phase via partial dislocation in zirconium

1.Introduction Zirconium(Zr)and its alloys show great applications in nu-clear and chemical industry thanks to their appropriate me-chanical properties,low ther...     

Comment on 'Active simulation of grounded inductors with CCII+ s and grounded passive elements'

This comment shows that circuits for active simulation of grounded inductors with plus-type second-generation current-conveyors (CCII + s) and grounded passive elements can be systematically derived from Sedra-Smith gyrator realization. In addition to the available realizations, new circuit topologies are presented. Some of the new topologies can yield inductance forms which are not realizable using the available topologies. Also, a new topology for realizing pure inductance without recourse to element matching conditions is presented.     

Large signal analysis of the SiGe HBT translinear harmonic mixer

Analytical expressions are obtained for the amplitudes of the desired output components of a SiGe translinear harmonic mixer excited by large-amplitude local oscillator and radio-frequency signals. Comparison with previously published calculated and simulated results is included.