A generic approach for embedded catalyst-supported vertically aligned nanowire growth

We demonstrate a general approach for growing vertically aligned, single-crystalline nanowires of any material on arbitrary substrates by using plasma-sputtered Au/Pd thin films as a catalyst through the vapor-liquid-solid process. The high-energy sputtered Au/Pd atoms form a reactive interface with the substrate forming nanoclusters which get embedded in the substrate, thus providing mechanical stability for vertically aligned nanowire growth. We demonstrate that our approach for vertically aligned nanowire growth is generic and can be extended to various complex substrates such as conducting indium tin oxide.     

Size-dependent surface-induced heterogeneous nucleation driven phase-change in Ge2Sb2Te5 nanowires

By combining electron microscopy and size-dependent electrical measurements, we demonstrate surface-induced heterogeneous nucleation-dominant mechanism for recrystallization of amorphous phase-change Ge2Sb2Te5 nanowires. Heterogeneous nucleation theory quantitatively predicts the nucleation rates that vary by 5 orders of magnitude from 190 to 20 nm lengthscales. Our work demonstrates that increasing the surface-to-volume ratio of nanowires has two effects: lowering of the activation energy barrier due to phonon instability and providing nucleation sites for recrystallization. The systematic study of the effect of surface in phase-change behavior is critical for understanding nanoscale phase-transitions and design of nonvolatile memory devices.     

Correction to: A Micellar Liquid Chromatographic Method for the Determination of Azosemide in Solubilized System

In the original publication of the article, the corresponding author's name was incorrectly published. The corresponding author's name should appear as Ashok Kumar.     

Bayesian network modelling for supply chain risk propagation

Supply chain risk propagation is a cascading effect of risks on global supply chain networks. The paper attempts to measure the behaviour of risks following the assessment of supply chain risk propagation. Bayesian network theory is used to analyse the multi-echelon network faced with simultaneous disruptions. The ripple effect of node disruption is evaluated using metrics like fragility, service level, inventory cost and lost sales. Developed risk exposure and resilience indices support in assessing the vulnerability and adaptability of each node in the supply chain network. The research provides a holistic measurement approach for predicting the complex behaviour of risk propagation for improved supply chain risk management.     

A metamaterial hepta‐band antenna for wireless applications with specific absorption rate reduction

Present article embodies the design and analysis of slotted circular shape metamaterial loaded multiband antenna for wireless applications with declination of SAR. The electrical dimension is 0.260 λ × 0.253 λ × 0.0059 λ (35 × 34 × 0.8 mm³) of proposed design, at lower frequency of 2.23 GHz. The antenna consists of circular shape rectangular slot as the radiation element loaded with metamaterial split ring resonator (SRR) and two parallel rectangular stubs, etched rectangular single complementary split‐ring resonator (CSRR) and reclined T‐shaped slot as ground plane. Antenna achieves hepta bands for wireless standards WLAN (2.4/5.0/5.8 GHz), WiMAX (3.5 GHz), radio frequency identification (RFID) services (3.0 GHz), Upper X band (11.8 GHz—for space communication) and Lower K_U band (13.1 GHz—for satellite communication systems operating band). Stable radiation patterns are observed for the operating bands with low cross polarization. The SRR is responsible for creating an additional resonating mode for wireless application as well as provide the declination in SAR about 13.3%. Experimental characteristic of antenna shows close agreement with those obtained by simulation of the proposed antenna.     

A heuristic SVM based pedestrian detection approach employing shape and texture descriptors

Multimedia Tools and Applications - Pedestrian detection is a vital issue in various computer vision applications such as smart security system, driverless car, smart traffic management system and...     

Implementation of hybrid fractal metamaterial inspired frequency band reconfigurable multiband antenna for wireless applications

In the present paper authors propose the design and analysis of a hepta band metamaterial inspired octagonal shape antenna using hybrid fractals for wireless applications. Multiband characteristics in the designed antenna is accomplished by introducing of slotted octagonal shape radiating part with hybrid fractal form of Moore curve and Koch curve and two SRR cells. The frequency band reconfigurability is obtained with aid of PIN diodes placed inside the strips connected between Moore curve (fused with centered Koch curve) and feedline. During ON mode of PIN diode antenna operates at seven microwave frequency S‐band WiMAX (3.4~3.69 GHz—IEEE 802.16e)/Lower C‐band terrestrial fixed and mobile broadband application (4.25~4.76 GHz)/C‐band WLAN (5.15~5.35/5.75~5.825 GHz—IEEE 802.11a] (5.4~5.9 GHz)/Lower X‐band Earth exploration‐satellite service ITU region 2 (7.9~8.4 GHz)/Upper X‐band Amateur satellite operating band (10.45~10.50 GHz)/Lower Ku‐band Radar communication application (13.25~13.75 GHz)/Middle Ku‐band Geostationary satellite service (14.2~14.5 GHz) covering various wireless applications. Proposed design exhibit hexa/hepta band features during OFF/ON mode of PIN diode. An acceptable gain, stable radiation characteristics, and good impedance matching are observed at all the resonant frequencies of the proposed structure.     

MAI Mitigation in MC-CDMA Systems Using Social Impact Based Wireless Communication Algorithm

Wireless Personal Communications - In this paper a novel optimization technique i.e. Social Impact based Wireless Communication Algorithm (SIWCA) has been applied on multi-carrier code division...     

Wireless Robotics: Opportunities and Challenges

Wireless robotics is one of the emerging fields in the world of automation. In-spite of research and standardization efforts around the world, the definition of the term “Robot” is still evolving. Robots have found application in many domains including home automation, industrial automation, health-care, surveillance, reconnaissance, planetary exploration or rescue missions. This paper addresses some of the opportunities, research challenges and standardization issues in wireless robotics with the focus on wireless and networking aspects.     

Sorptive sequestration of 2‐chlorophenol by zeolitic materials derived from bagasse fly ash

BACKGROUND: Water pollution by toxic organic compounds is of great concern and increasingly there are demands for effective sorbents to remove them. Bagasse fly ash, a sugar industry solid waste with disposal problems, was utilized as a source for the synthesis of zeolitic material. The efficiency of virgin and synthesized material was examined for the sorption of 2‐chlorophenol. RESULTS: Zeolitic materials have been synthesized by alkaline hydrothermal and fusion methods. Zeolite P and Analcime were the major components of the zeolitic material. These materials were characterized by XRF, PXRD, FTIR and SEM and were found to have improved morphology with new crystalline phases. Batch sorption experiments for the removal of 2‐chlorophenol by virgin and zeolitic materials were carried out to evaluate isotherm capacities and kinetics of sorption processes. The Langmuir isotherm better fits the equilibrium data which concur with physical sorption. Kinetic studies showed better correlation coefficients for pseudo‐second‐order and intraparticle diffusion model, confirming that the sorption rate was controlled by film diffusion followed by pore diffusion. Desorption studies were performed to regenerate the activity of the spent sorbents. The practical utility of sorbents was tested by column study. CONCLUSION: Bagasse fly ash, readily available at very low cost was successfully converted into zeolitic material. The synthesized zeolitic material showed enhanced capacities for the sorption of 2‐chlorophenol and can be utilized as a low cost sorbent for treatment of phenolic waste‐water. Copyright © 2011 Society of Chemical Industry