014120   Ananthkrishnan N;Sinha N K (NO, , B-257, Indian Institute of Technology campus Powai, Mumbai-400 076, Email: dr.akn.19@gmail.com) : Why birds and airplanes need no vertical tail. J Aerospace Sci Technol 2014, 66(1), 21-7.

Question of why airplanes need a vertical tail whereas birds seem to do very well without one has been longstanding. Some have suggested that it is a matter of scale; that the rationale for a vertical tail disappears when coming down the scale from the regime of "full" scale aircraft to bird/ small scale flight regime. This hypothesis has now been debunked. This paper shows that the lateral-directional modal dynamics and stability criteria remain unchanged over the relevant range of flight Reynolds numbers. It conclusively establishes that a vertical tail is not essential for directional or lateral stability at any scale from that of bird flight to "full" scale airplane flight.

2 illus, 16 ref

014119   Anand Raji R;Regu Kumar A P;Purohit S;Lakshmi T;Dwivedi V;Keshari Kumar (NO, Defence Avionics Research Establishment, Bangalore-560 075, Email: anandraji@dare.drdo.in) : Advanced mission management system for unmanned aerial vehicles. Def Sci J 2014, 64(5), 438-44.

Paper presents advanced mission management system (MMS) for unmanned aerial vehicles, based on integrated modular avionics (IMA) architecture. IMA architecture enables the MMS to host high end functions for autonomous navigation and attack. MMS is a collection of systems to execute the mission objectives. The system constitutes mission computer (MC), sensors and other sub-systems. The MMS-MC needs to execute advanced algorithms like terrain referenced navigation, vision-aided navigation, automatic target recognition, sensor fusion, online path planning, and tactical planning for autonomy and safety. This demands high-end architecture in terms of hardware, software, and communication. The MMS-MC is designed to exploit the benefits of IMA concepts such as open system architecture, hardware and software architecture catering for portability, technology transparency, scalability, system reconfigurability and fault tolerance. This paper investigates on advanced navigation methods for augmenting INS with terrain-referenced navigation and vision-aided navigation during GPS non-availability. This paper also includes approach to implement these methods and simulation results are provided accordingly, and also discusses in a limited way, the approach for implementing online path planning.

9 illus, 24 ref

014118   Amiri O;Salavati-Niasari M;Mousavi-Kamazani M;Ghanbari D;Sabet M;Saberyan K (Young Researchers Club, Kashan Branch, Islamic Azad Univ, Kashan, Iran, Email: salavati@kashanu.ac.ir) : New sonochemical method for preparation of different morphologies of CuInS₂ nanostructures. Bull Mater Sci 2014, 37(5), 1079-85.

CuInS₂ nanostructures were synthesized by sonochemical route using (bis(salicylate)copper(II)) as a new copper precursor. The effects of different parameters such as sulphur source, solvent, power of irradiation and reaction time on the morphology of the products were investigated. Nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), photoluminescence (PL) and Fourier transform infrared (FT-IR) spectroscopy. CuInS₂ nanostructures paste was prepared by doctor's blade technique on the transparent conductive oxide (TCO). The fill factor (FF), open circuit voltage (V_oc), and short circuit current (I_sc) were obtained by I-V characterization.

12 illus, 1 table, 19 ref

014117   Al Rawi O;Al Ani R;Yousef Z A (NO, , ) : Causes of inefficient site cost management systems in Arabian gulf construction companies. J Constr Engng Technol Mgmt 2014, 4(3), 31-45.

Cost of construction projects has a long history of exceeding the planned cost. At the project level, this is termed as "Project Cost over Run". This research reviews the main causes of the inefficiency in the existed cost management systems applied by the Arabian Gulf Contracting Companies at the construction stage. The requirements of having an efficient cost management system (recording, monitoring and controlling functions) have been collected from previous researches to be used in a field survey on the construction companies in the Arabian Gulf to highlight the main causes behind inefficient management functions (monitoring and controlling of site costs in the construction projects in the region. This research is the first part of a M.Sc. research work which has been taken place on Saudi Arabian and Bahraini contracting companies to identify the efficiency of existed cost monitoring and control methods applied by these companies in their projects. The highlighted causes will assist project management of the construction companies in the Arabian Gulf region, as well as the other contracting companies, in evaluating and improving their monitoring and controlling their site cost at the construction stage.

014116   Akinwumi I I (Civil Engineering Dep, Covenant University, P. M. B. 1023, Ota, Nigeria, Email: isaac.akinwumi@covenantuniversity.edu.ng) : Earth building construction processes in Benin City, Nigeria and engineering classification of earth materials used. Indian J Tradl Knowledge 2014, 13(4), 686-90.

Villages in Oka, Use and Uselu were visited and interviews of earth constructors in these locations were conducted to determine their mud house construction techniques. Earth building materials were also taken from these villages and laboratory tests were conducted on the soil samples in order to classify them. Natural moisture content, sieve and hydrometer analyses, and Atterberg limits tests were performed in the laboratory. The interaction between the culture, tradition and earth construction technique of the Benin people was revealed from the interview sessions. The soil samples at the three locations were suitable for mud house construction, based on the results of laboratory tests. It was revealed from the interview sessions that the construction technique widely used in these locations is similar in procedure to that of cob construction, except that straws are not added. The soil samples from the three villages were classified as silty, clayey sand (SC-SM), according to Unified Soil Classification System. According to American Association of State Highway and Transportation Officials, soil samples from Use, Uselu and Oka were classified as A-4, A-6 and A-7, respectively. The soil samples taken from Use and Uselu were found to be more suitable for mud house construction than that from Oka, based on the results of laboratory tests.

5 illus, 16 ref

014115   Ahuja A K;Chakka R (NO, Meerut Institute of Engineering and Technology (MIET), Meerut-250005, Email: ramchakka@yahoo.com) : Analysis of the performance-improvement due to a new receiver for baseband telecommunications, and development of a fast predictive model. J scient ind Res 2014, 73(9), 577-87.

Extensive simulation study of the TTS-MF receiver (reported in1) is performed in order to investigate the dependence of the achieved performance-improvement over the classical receiver, for p-q signals, for an extensive range of signal parameters p,q and SNR. Results obtained show an interesting dependence of the performance-improvement on the sum p+q, which we term in this paper as the "p+q statistic". This important discovery is made use of to develop fast prediction-models for the performance-improvement, as closed form functions of one parameter of the signal which is the p+q statistic at a given SNR. These models are then tested and evaluated extensively, for accuracy, in a systematic way. Such fast prediction-models are highly useful for telecom design, operation, maintenance and enhancement.

4 illus, 1 table, 22 ref

014114   Adhikari D;Bhattacharya C (NO, Symbiosis Institute of Technology, Pune-412 115, Email: adhikaridebashis@gmail.com) : Performance analysis of ultra wideband multiple access time hopping-pulse shape modulation in prsence of timing jitter. Def Sci J 2014, 64(5), 464-70.

In short-range networks such as wireless personal area networks (WPAN), multiple user wireless connectivity for surveillance would require a wireless technology that supports multiple streams of high-speed data and consumes very little power. Ultra wideband (UWB) technology enables wireless connectivity across multiple devices (users) addressing the need for high-speed WPAN. Apart from having a distinct advantage of higher data rate over Bluetooth v4.0 (24 Mbps), the UWB technology is also found to be tolerant to frequency-selective multipath fading. In this paper authors discuss a time-hopping pulse shape modulation UWB signalling scheme for ad-hoc high bit rate wireless connectivity for defence applications. Authors analyse multiple access interference for both Gaussian channel and frequency selective multipath fading channel to compare the effects of timing jitter on two types of pulse shapes, namely modified Hermite pulse (MHP) and prolate spheroidal wave functions (PSWF). Authors make a comparative analysis of the system performance with respect to PSWF and MHP to ascertain robustness to timing jitter. In the process, authors introduced a new metric of decision factor in timing jitter analysis.

7 illus, 18 ref

014113   Adediji A T;Mandeep J S;Ismail M (Electrical Dep, Electronic & Systems Engineering, Faculty of Engineering & Built Envir, Bangi, Malaysia, Email: kunleadediji2002@yahoo.co.uk) : Meteorological characterization of effective earth radius factor (k-Factor) for wireless radio link over akure, Nigeria. MAPAN 2014, 29(2), 131-41.

The propagation loss on a terrestrial line-of-sight wireless link is influenced by atmospheric and seasonal conditions. The reliability of the link is also affected by k-factor values which is usually taken as 4/3 in regions where there is dearth of data; however, this value can only be used for gross planning. Therefore, it is important to determine its average and effective value for adequate path engineering because its value depends on local climatic conditions and it is terrain specific. In this study, k-factor values for the entire seasonal cycle within 2007-2009 in Akure are analyzed. The work is aimed at observing the distribution of k-factor and its influence on terrestrial point to point, line-of-sight radio link over Akure, south western Nigeria. From the study therefore, an average value of -63.22 N-units/km and 1.50 were obtained for refractivity gradient and k-factor respectively. Also, super-refractive condition was deduced to be mostly prevalent at higher antenna heights of 100-150 m.

11 illus, 3 tables, 23 ref

014112   Abraham L;Sasikumar M (NO, Lal Bahadur Shastri Institute of Technology for Women, Trivandrum, Kerala) : Analysis of satellite images for the extraction of structural features. IETE Tech Rev 2014, 31(2), 118-27.

The development of high-resolution satellite imaging sensors has enhanced the collection of remotely sensed data and offers a cost-effective way to obtain information over large areas. The main structural features that are to be detected through satellite imaging are roads, buildings, and bridges. Detection of clouds and shadows supports the extraction of these features. However, the type of satellite images provided by different imaging sensors varies widely depending on spatial and spectral resolutions, which makes the process of feature extraction more complicated. This paper presents a detailed analysis of different algorithms developed to extract structural features using a variety of satellite images available for a single region. A comparative study of various techniques is done to justify the best method for the extraction of each feature.

12 illus, 2 tables, 20 ref

014111   Abareshi M;Zebarjad S M;Goharshadi E K (Chemistry Dep, Payame Noor Univ, 19395-3697 Tehran, Iran, Email: maryamabareshi@yahoo.com) : Non-isothermal crystallization kinetics of polyethylene-clay nanocomposites prepared by high-energy ball milling. Bull Mater Sci 2014, 37(5), 1113-21.

Non-isothermal crystallization kinetics of pure medium density polyethylene (MDPE) and MDPE-clay nanocomposites have been investigated by differential scanning calorimeter. The modified Avrami, Ozawa, Liu and Ziabicki equations have been applied to describe non-isothermal crystallization process. The results of Avrami analysis showed a very complicated crystallization mechanism. Although, Ozawa equation failed to provide an adequate description for non-isothermal crystallization process, Liu equation could describe it well. The data showed the crystallization rate of MDPE and nanocomposites raises with increasing cooling rate and the crystallization rate of nanocomposite is faster than that of MDPE at a given cooling rate. Ziabicki's kinetic crystallizability index showed that clay can increase the ability of MDPE to crystallize, when it is cooled at unit cooling rate. The activation energy of samples has been evaluated by Kissinger method. The results showed that the activation energy of nanocomposite was lower than that of MDPE.

8 illus, 6 tables, 28 ref

013094   Zielinska B (Institute of Chemical and Environment Engineering, West Pomeranian Univ of Technology, Szczecin, Pulaskiego 10, 70-322 Szczecin, Poland, Email: bzielinska@zut.edu.pl) : Photocatalytic hydrogen generation with Ag-loaded LiNbO₃. Bull Mater Sci 2014, 37(4), 911-16.

In this contribiution LiNbO₃ and Ag-loaded LiNbO₃ photocatalysts were tested in the reaction of hydrogen evolution. The silver modified samples contained different loading of co-catalyst in the range of 0.5-4 wt%. It was essential to optimize the sample composition to achieve an efficient hydrogen evolution. The optimal sample contained 2 wt% of silver. The detailed analysis indicated that silver was deposited on the surface of LiNbO₃ in the form of Ag₂O. Therefore, it is supposed that Ag₂O was responsible for the enhanced photocatalytic activity in the studied reaction. The crystallographic phases and optical and vibronic properties were examined by X-ray diffraction (XRD) and diffuse reflectance (DR) UV-Vis and resonance Raman spectroscopic methods, respectively. Morphology of the produced samples were studied using a high-resolution transmission electron microscope (HRTEM).

8 illus, 24 ref

013093   Zhang P;Ya Nan Z;Fu Qing L;Tain Hang Z;Wang P (NO, School of Water Conservancy and Environment Engineering Zhengzhou Univ, Zhengzhou-450 001, Email: zhangpeng8008@gmail.com) : Mechanical properties of fly ash concrete composite reinforced with nano SiO₂ and steel fibre. Curr Sci 2014, 106(11), 1529-37.

Parametric experimental study has been conducted to study the effect of nano-SiO₂ particles and steel fibres on the mechanical properties of the concrete composite containing fly ash. Five different nano-SiO₂ contents (1%, 3%, 5%, 7% and 9%) and five different steel fibre contents (0.5%, 1%, 1.5%, 2% and 2.5%) were used. The results indicate that addition of nano-SiO₂ and steel fibres decreases the slump and slump flow of the fresh concrete composite containing fly ash, and both the slump and slump flow decrease gradually with the increase in nano-SiO₂ and steel fibre content. The addition of nano-SiO₂ improves the mechanical properties of concrete composites containing fly ash. There is an increase in the compressive strength and compressive modulus of elasticity with increase of nano-SiO₂ content when it is below 5%, while they begin to decrease after the nano-SiO₂ content is beyond 5%. Steel fibres help improve the mechanical properties of concrete composite containing fly ash and nano-particles. With the appropriate fibre content, the reinforcement of steel fibres on the compressive strength and compressive modulus of elasticity of the concrete composite becomes more obvious as the fibre content increases.

6 illus, 5 tables, 43 ref

013092   Zandvliet C;Bandyopadhyay N R;Ray D (School of Materials Science and Engineering, Indian Institute of Engineering Science and Technology, Shibpur, Howrah-711 103, Email: zandvlietclio@yahoo.fr) : Water absorption of jute/polylactic acid composite intended for an interior application and comparison with wood-based panels. J Instn Engrs : Ser D 2014, 95(1), 49-55.

Jute/polylactic acid (PLA) composite is of special interest because it is entirely from renewable resources with high mechanical properties. Thus, it could be a more eco-friendly alternative to the conventional wood-based panels made of formaldehyde resin which is asserted to be carcinogenic. Yet the water affinity of the natural fibres and susceptibility of polylactic acid towards hydrolysis raise a question about the water resistance of such composites in service condition. In this work, the water absorption behaviour of jute/PLA composites, jute/ maleated polypropylene was investigated with regard to interior applications following the standard test method in accordance to ISO 16983:2003 'Wood-based panels-determination of swelling in thickness after immersion in water' and compared to standard of wood-based panels. Untreated and treated jute/PLA composites exhibited a superior water resistance property compared to particle-board, MDF and hardboard and they are by far, below the minimum requirement of the ISO standard 16983.

4 illus, 19 ref

013091   Yuan-Shyi P C;Mei-Fang W;Feng-Tsung C; Ming-Hon H (Industrial Engineering & Management Dep, Chaoyang Univ of Technology, Taiwan, Email: hwangmh@cyut.edu.tw) : Replenishment lot sizing with failure in rework and an enhanced multi-shipment policy. J scient ind Res 2014, 73(10), 648-52.

This study determines the optimal replenishment lot size for a manufacturing system with failure in rework and an enhanced multi-shipment policy. An economic lot size problem incorporated a multi-delivery policy and quality assurance was examined in a recent study^{1, with the primary intention of reducing a producer's inventory holding cost, this paper formulated an enhanced multi-shipment distribution policy to improve the solution for such a specific problem. With a help of mathematical modelling and optimization technique, the optimal replenishment lot size for the proposed system is obtained. As a result, not only the holding cost but the entire expected system cost per unit time is minimized. A numerical example was provided to show practical applicability of the obtained results and to demonstrate significant savings in a producer's stock holding cost.}

2 illus, 32 ref

013090   Xu J;Yang Z;Wang H;Zhang X (School of Material Science and Engineering, Shaanxi Normal Univ, Xi'an 710062, China, Email: yangzp@snnu.edu.cn) : Structural evolution, electrical and optical properties of AZO films deposited by sputtering ultra-high density target. Bull Mater Sci 2014, 37(4), 895-902.

Aluminum-doped zinc oxide (AZO) target was fabricated using AZO nanopowders synthesized by co-precipitation method and then the AZO films with different thicknesses were deposited on glass by d.c. magnetron sputtering at room temperature. AZO target is nodules free and shows homogeneous microstruc-ture, ultra-high density and low resistivity. ZnAl₂O₄ phase appears in AZO target and disappears in AZO films. All AZO films show c-axis preferred orientation and hexagonal structure. With increasing film thickness from 153 to 1404 nm, the crystallinity was improved and the angle of (002) peak was close to 34.45°. The increase in grain size and surface roughness is due to the increase in film thickness. The decrease of resistivity is ascribed to the increases of carrier concentration and Hall mobility. The lowest resistivity is 9.6 x 10^{-4 Ω.cm. The average transmittance of AZO films exceeds 80%, and a sharp fundamental absorption edge with red-shifting is observed in the visible range. The bandgap decreases from 3.26 to 3.02 eV.}

10 illus, 31 ref

013089   Wen Z;Yin X;Jiang Z (School of Mechatronics Engineering, Zhengzhou Institute of Aeronautical Industry Management, Zhengzhou 450015, China, Email: levinzhwen@126.com) : Applications of electrostatic sensor for wear debris detecting in the lubricating oil. J Instn Engrs : Ser C 2013, 94(3), 281-6.

In this study, an advanced monitoring technology has been presented based on the electrostatic induction principle to monitor timely wear fault on-line. The paper begins with the principle of the electrostatic monitoring technology, then we focus on the electrostatic sensor, the most important component in the electrostatic monitoring system, establish a measurement model for an electrostatic sensor with the given structure parameters. Based on the measurement model, we use the finite element method to analyze the characteristics of an electrostatic sensor for wear debris detecting in lubricating oil. Lastly we build an experiment platform to validate the feasibility of the electrostatic monitoring method. The experiment results show, to some extent, that the electrostatic signal can reflect the relative density of wear debris, and the sensor proposed can satisfy the primary demand of wear debris on-line monitoring.

8 illus, 13 ref

013088   Wang X;Qian H (NO, Changshu Institute of Technology, Jiangsu, Changshu-215500, China) : Enhanced inter-domain mobile protocol for IPv6-based wireless networks. IETE J Res 2014, 60(4), 288-95.

This paper proposes an enhanced inter-domain mobile protocol for IPv6-based wireless networks. In this protocol, the domain-based architecture is proposed and the IPv6 address structure is presented. In this architecture, a wireless network is made up of multiple global domains, and a global domain consists of multiple local domains. Based on this architecture, the inter-domain handover algorithm is proposed. In this algorithm, a mobile node is always identified by its home address during its life time, the handover in the link layer and the one in the network layer are performed in parallel, and a mobile node always receives data from the same border mobile access gateway. Moreover, a mobile node uses the channel information to directly perform the handover in the link layer. Therefore, the handover delay is shortened and the packet loss is lowered. This paper evaluates the performance parameters of this scheme, and the data results show that this scheme lowers the handover delay and packet loss.

9 illus, 2 tables, 12 ref

013087   Wang W;Song Y;Liu Q;Yang K (College of Chemical Engineering, Inner Mongolia Univ of Technology, Huhhot 010051, P.R. China, Email: yangkeli@imut.edu.cn) : Facile synthesis and catalytic properties of silver colloidal nanoparticles stabilized by SDBS. Bull Mater Sci 2014, 37(4), 797-803.

A facile method was explored to prepare stable silver colloidal nanoparticles (AgCNPs) in water. Sodium dodecyl benzene sulfonate (SDBS) was used as the stabilizing agent, without addition of any co-surfactant. The reaction was rapid and the product prepared at different conditions was measured by transmission electron microscopy (TEM) and UV-Vis spectroscopy. The results showed that AgCNPs stabilized by SDBS was stable in water with narrow size distribution (1-5 nm). The amount of surfactant has great influence on the products. When the molar ratio of Ag^{+ to SDBS increased to 1:4, AgCNPs can be obtained with high dispersion (2-3 nm), which has high catalytic activity on reduction of 4-nitrobenzoic acid to 4-aminobenzoic acid.}

11 illus, 28 ref

013086   Wan Q;Li P;Li Y;Zhai F;Zhang W;Cui L;Volinsky A A;Qu X (Institute for Advanced Materials and Technology, Univ of Science and Technology, Beijing, Beijing 100083, China, Email: ustbliping@126.com) : CO impurities effect on LaNi_4.7Al_0.3 hydrogen storage alloy hydrogenation/dehydrogenation properties. Bull Mater Sci 2014, 37(4), 837-42.

LaNi_4.7Al_0.3 alloy was prepared by vacuum induction melting in high purity helium atmosphere, and the ingot was pulverized into 200-400 mesh powder after annealing. X-ray diffraction (XRD) and scanning electron microscopies (SEM) were utilized to study the alloy morphology and phase structure. X-ray photoelectron spectroscopy (XPS) was used for surface analysis. The poisoned alloy was tested at 30 °C in the mixture gas by thermogravimetric and differential thermal analyses (TG + DTA). The hydrogen storage properties were studied by the pressure-composition-temperature test. The activated sample was completely deactivated after only 3 hydriding/dehydriding cycles in hydrogen containing 300 ppm CO at 30 °C, but hydrogen storage capacity did not degrade when tested at 80 °C. Additionally, two different steps appeared in the absorption processes. Combined with XRD, XPS and TG + DTA results, an explanation for this phenomenon is given.

9 illus, 36 ref

013085   Verma R S;Jo M A;Deora A S (Mechanical Engineering Dep, Army Institute of Technology, Dighi Hills, Alandi Road, Pune-411 015, Email: adityakrishna121@gmail.com) : Forced convection across horizontal hot cylinder using slotted deflector plate. J Instn Engrs : Ser C 2013, 94(3), 275-9.

According to Kirchoff-Helmhotlz solution for flow across a horizontal cylinder, the boundary layer sep-arates at an angle of 55° from horizontal plane, so due to this separation phenomenon of boundary layer, the heat transfers from the upper side of a hot cylinder is minimum. Heat transfer from upper side can be increased by pre-venting the separation of boundary layer. Here we delay the separation of boundary layer by using a slotted deflector plate. Due to this accelerated air passes over upper side of the cylinder. The optimum distance at which the plate is to be kept from the cylinder is found out through this experiment. This experiment is also carried out by varying the width of the slot, the heat input to the cylinder and the velocity of flow of the air. We find that this method is more effective at higher temperatures and the highest temperature difference achieved was 20% which is significant for cooing industrial equipments.

6 illus, 2 tables, 11 ref

013084   Verma D;Gope P C;Shandilya A (NO, College of Engineering Roorkee, Roorkee, Uttarakhand, Email: dverma.mech@gmail.com ) : Evaluation of mechanical properties and morphological studies of bagasse fibre (chemically treated/untreated)-CaCO₃ epoxy hybrid composites. J Instn Engrs : Ser D 2014, 95(1), 27-34.

In past few years natural fibre composites have become very important part of research as potential structural material. The present study deals with a new class of chemically treated/untreated natural fibre and calcium carbonate reinforced composites. In the present investigation composites of bagasse fibre (10% w/w) and calcium carbonate powder of size ≤30 μm (2 and 4% w/w) with epoxy resin have been examined. The lengths of bagasse fibre have been varied from 1 to 5 mm. The fibres were chemically treated with NaOH (5% w/v). Morphological changes of the fibres were observed under the scanning electron microscope. Addition of calcium carbonate showed increased mechanical properties of the developed composites like, flexural strength, compression strength. The composites reinforced with chemically treated fibres show better mechanical properties as compared to the composites reinforced with untreated fibres.

8 illus, 7 tables, 14 ref

013083   Venkateswara Rao A;Veeraiah V;Prasada Rao A V;Kishore Babu B;Swarna Latha B;Rama Rao K (Physics Dep, Andhra Univ, Visakhapatnam-530 003, Email: avrtoavr@gmail.com) : Structural, spectroscopic and electrochemical study of V<. Bull Mater Sci 2014, 37(4), 883-8.

Vanadium substituted LiTi₂(PO₄)₃ (LTP) samples of composition of Li_1-x[Ti_2-xV_x(PO₄)₃ (x = 0.0, 0.05, 0.10 and 0.15) have been prepared by solid-state reaction method. XRD data for these compositions indicated the formation of phase pure materials of rhombohedral structure with space group R3c (167). Microstructural studies by scanning electron microscope indicated particle size in the range of 0.5-1 μm. Electrochemical impedance studies showed that ionic conductivity is high for x = 0.10 composition, a.c. and d.c. conductivity results up to 573 K are in accordance with the Jonscher's power law. Cyclic voltammetry study showed its electrochemical stability in the voltage range from 0.5 to 3.5 V.

7 illus, 2 tables, 20 ref

013082   Trivedi S;Sharma S C;Harsha S P (Vibration and Noise Control Lab, Mechanical & Industrial Engineering D, Indian Institute of Technology Roorkee, Roorkee-247 667, UK, Email: surajfme@iitr.ac.in) : Dynamic analysis of single walled boron nitride nanotube reinforced composite based nanomechanical resonator. J Instn Engrs : Ser D 2014, 95(1), 7-18.

Boron nitride nanotubes (BNNTs) possess extremely high stiffness and strength and may provide the ultimate reinforcing materials for the development of nanocomposites. In this paper, the Young's modulus of BNNT based composites are evaluated using a 3-D nano-scale representative volume element based on continuum mechanics (CM) and using the finite element method (FEM). Additionally, the suitability of the BNNTs reinforced polymeric composites as nanomechanical resonators, using CM based approach and FEM is illustrated in this paper. Analytical formulas based on CM are used to examine the mass sensitivity of single walled BNNT (SWBNNT) reinforced composite considered as a thin wall BNNT for different aspect ratios and volume fractions of BNNT in composites. The FEM analysis, considering SWBNNT as a transversely anisotropic material is performed and results are compared with the CM based approach. The results indicated that the mass sensitivity of SWBNNT reinforced composite based nanomechanical resonators can reach 10^{-3 fg and a logarithmically linear relationship exists between the resonant frequency and the attached mass, when mass is larger than 10-3 fg. The simulation results which have been obtained based on FEM are found to be in good agreement with the analytical approach used in this paper.}

16 illus, 6 tables, 43 ref

013081   Thirumalai T;Subramanian R;Kumaran S; Dharmalingam S;Ramakrishnan S S (Metallurgical Engineering Dep, PSG College of Technology, Coimbatore, Email: thirumalaimet@gmail.com) : Production and characterization of hybrid aluminum matrix composites reinforced with boron carbide (B₄C) and graphite. J scient ind Res 2014, 73(10), 567-70.

Aluminum matrix composites have been reinforced with Boron carbide (B₄C) and Graphite (Gr) for increasing mechanical properties and wear resistance. Additions of Boron carbide (B₄C) improves both strength and wear resistance of composites, but addition of B₄C alone in higher amounts makes the composite brittle and machining difficult. Thus, B₄C can be advantageously used as a reinforcement to overcome the problem of strength reduction in Gr reinforced composites, resulting in hybrid composites. Aluminum matrix composites reinforced with up to 12 wt % B₄C and 3 wt % Gr particulates are investigated in the present study. Hybrid composites exhibit better wear characteristics compared to aluminium alloy. Wear tests were carried out with loads varying from 10 to 40 N and sliding distances of 500 and 1000 m with a constant sliding speed of 1m per second. An interaction between load and sliding distance was observed in the composites which may be attributed to the presence of Gr particulates. Decrease in wear with an increase in speed and vice versa were observed with both load and sliding distance. Hardness of the composites measured using Vicker's Hardness Tester indicated that hardness increased with increasing percent of B₄C reinforcement while addition of Gr imparted the lubrication effect in the composites.

4 illus, 3 tables, 17 ref

013080   Tahir M;Siddiqi M U (Electrical and Computer Engineering Dep, International Islamic Univ, Malaysia, Selangor, Malaysia) : Hybrid scheme for wireless physical layer security based on encryption and channel pre-compensation. IETE J Res 2014, 60(4), 267-75.

In this paper, a hybrid scheme to provide wireless physical layer security based on encryption and wireless channel pre-compensation is presented. The physical layer security is provided by converting the signal constellation into a higher order constellation by using conventional encryption (symmetric key encryption) and then using channel state information (i.e. amplitude and phase variation), which is location specific, to further encrypt the constellation before transmission. Since detection and demodulation are based upon the known signal constellation, which is not known in advance in our case, it becomes difficult for the eavesdropper to determine the original signal constellation. The data intercepted by the eavesdropper is unintelligible due to the combined effect of encryption and pre-compensation. Using bit error rate (BER) as performance metric, it is found that the eavesdropper suffers from high BER as compared to its legitimate counterpart hence providing secure communication. The developed scheme was tested with existing wireless communication standard IEEE 802.11 to show the practical application of the scheme.

8 illus, 1 table, 20 ref

013079   Song M Y;Kwak Y J;Lee S H;Park H R (Advanced Materials Engineering Div, Hydrogen & Fuel Cell Research Centre, Engineering Research Institute,, 567 Baekje-daero Deokjin-gu Jeonju 561-756, South Korea, Email: songmy@jbnu.ac.kr) : Comparison of hydrogen storage properties of pure Mg and milled pure Mg. Bull Mater Sci 2014, 37(4), 831-5.

Hydrogen storage properties of pure Mg were studied at 593 K under 12 bar H₂. In order to increase the hydriding and dehydriding rates, pure Mg was ground under hydrogen atmosphere (reactive mechanical grinding, RMG) and its hydrogen storage properties were subsequently investigated. Pure Mg absorbed hydrogen very slowly. At the number of cycles (n) of 1, pure Mg absorbed 0.05 wt% H for 5 min, 0 08 wt% H for 10 min and 0.29 wt% H for 60 min at 593 K under 12 bar H₂. Activation was completed at the fifth cycle. At n = 6, pure Mg absorbed 1 76 wt% H for 5 min, 2.17 wt% H for 10 min and 3.40 wt% H for 60 min. The activation of pure Mg after RMG was completed at the sixth cycle. At n = 7, pure Mg after RMG absorbed 2 57 wt% H for 5 min, 3.21 wt% H for 10 min and 4.15 wt% H for 60 min.

8 illus, 23 ref

013078   Shinde P S;Tripathi V K;Singh K K;Sarkar P K; Kumar P (Mechanical Engineering Dep, College of Engineering, Pune, Pune, Maharashtra, Email: prkumar@iitk.ac.in) : Reduction in stress intensity factor of a compact tension specimen by bonding symmetrical GFRP patches. J Instn Engrs : Ser C 2013, 94(3), 239-44.

Reduction in stress intensity factor (SIF) of an acrylic compact tension (CT) specimen is studied by symmetrical bonding of glass fiber reinforced plastic (GFRP) patches on both sides of the specimen. The CT specimen was designed and developed to satisfy all dimensional constraints for plane strain condition. A suit-able load fixture using dead weight for higher accuracy was designed for the purpose. The numerical and experimental analysis of CT specimen with varying geometry of the GFRP patches was carried out to analyze their effect on SIF of the specimen. The strain near the crack tip was measured by bonding a small strain gauge to estimate the equivalent SIF of the CT specimen. The test data was compared with the results of numerical analysis carried out using ANSYS software. The variation in strain value determined through theoretical analysis, numerical evalu-ation and experimental measurement is within 7%. The equivalent SIF was found to be drastically reduced after bonding the CT specimen with GFRP patches.

6 illus, 17 ref

013077   Roy S;Shome S N;Nandy S;Ray R;Kumar V (NO, CSIR-Central Mechanical Engineering Research Institute, Durgapur-713 209, Email: sroy002@gmail.com) : Trajectory following control of AUV: a robust approach. J Instn Engrs : Ser C 2013, 94(3), 253-65.

Robust control technique based on the second method of Lyapunov is proposed in this paper for accurate trajectory tracking of autonomous underwater vehicles (AUVs). The difficulty in control of AUVs not only resides in the highly non-linear and coupled dynamics but is enhanced by modeling errors, parametric uncertainty and payload variations depending on application requirements. Environmental hazards such as ocean currents sometimes dominate and render the control of underwater systems more challenging. The proposed control technique addres-ses the design of a robust controller for AUVs incorporating the effects of the aforementioned uncertain paradigms with known bounds. The controller performance is verified using the real-life parameters of an operational AUV considering a few uncertainties.

5 illus, 3 tables, 15 ref

013076   Reddi P D;Mukhopadhyay N K;Majumdar B;Singh A K;Meena S S;Yusuf S M;Prasad N K (Metallurgical Engineering Dep, Indian Institute of Technology, Banaras Hindu Univ, Varanasi-221 005, Email: nandkp.met@itbhu.ac.in) : Synthesis of Fe-Si-B-Mn-based nanocrystalline magnetic alloys with large coercivity by high energy ball milling. Bull Mater Sci 2014, 37(4), 815-21.

Alloys of Fe-Si-B with varying compositions of Mn were prepared using high energy planetary ball mill for maximum duration of 120 h. X-ray diffraction (XRD) analysis suggests that Si gets mostly dissolved into Fe after 80 h of milling for all compositions. The residual Si was found to form an intermetallic Fe₃Si. The dissolution was further confirmed from the field emission scanning electron microscopy/energy dispersive X-ray analysis (FE-SEM/EDX). With increased milling time, the lattice parameter and lattice strain are found to increase. However, the crystallite size decreases from micrometer (75-95 μm) to nanometer (10-20 nm). Mossbauer spectra analysis suggests the presence of essentially ferromagnetic phases with small percentage of super paramagnetic phase in the system. The saturation magnetization (M_s), remanance (M_r) and coercivity (H_c) values for Fe-OMn sample after 120 h of milling were 96.4 Am^{2/kg, 11.5 Am2/kg and 12.42 k Am-1, respectively. However, for Fe-10Mn-5Cu sample the M_s, H_c and M_r values were found to be 101.9 Am2/kg, 10.98 kA/m and 12.4 Am2/kg, respectively. The higher value of magnetization could be attributed to the favourable coupling between Mn and Cu.}

9 illus, 2 tables, 27 ref

013075   Rashad M M;Ibrahim I A;Osama I;Shalan A E (NO, Central Metallurgical Research and Development Institute (CMRDI), P.O. Box 87, Helwan, Cairo, Egypt, Email: a.shalan133@gmail.com) : Distinction between SnO₂ nanoparticles synthesized using co-precipitation and solvothermal methods for the photovoltaic efficiency of dye-sensitized solar cells. Bull Mater Sci 2014, 37(4), 903-9.

Nanocrystalline SnO₂ powders prepared by solvothermal and co-precipitation pathways have been characterized using XRD, TEM, UV-Visible absorption, BET specific surface area (S_BET) method, EIS and J-V measurements. The obtained powders have a surface area and size of 38.59 m^{2/g and 10.63 nm for the SnO₂ powders synthesized solvothermally at a temperature of 200 °C for 24 h, while the values were 32.59 m2/g and 16.20 nm for the formed hydroxide precursor annealed at 1000 °C for 2 h by co-precipitation route. The microstructure of the formed powders appeared as tetragonal-like structure. Thus, the prepared SnO₂ nanopowders using two pathways were applied as an electrode in dye-sensitized solar cell (DSSC). The photoelectrochemical measurements indicated that the cell presents short-circuit photocurrent (J_sc), open circuit voltage (F_oc) and fill factor (FF) were 7.017 mA/cm2, 0.690 V and 69.68%, respectively, for solvothermal route and they were 4.241 mA/cm2, 0.756 V and 66.74%, respectively, for co-precipitation method. The energy conversion efficiency of the solvothermal SnO₂ powders was considerably higher than that formed by co-precipitation powders; <126>3.20% (solvothermal) and 2.01% (co-precipitation) with the N719 dye under 100 mW/cm2 of simulated sunlight, respectively. These results were in agreement with EIS study showing that the electrons were transferred rapidly to the surface of the solvothermal-modified SnO₂ nanoparticles, compared with that of a co-precipitation-modified SnO₂ nanoparticles.}

5 illus, 2 tables, 22 ref

013074   Mohan V;Dey N C (NO, Bengal Engineering and Science Univ, Shibpur, Howrah, West Bengal, Email: vijayant245singh@gmail.com) : Assessment of ground vibration and plotting of contour map of surface mine blasting. J Instn Engrs : Ser D 2014, 95(1), 1-6.

In recent days, due to increase in demand of coal and minerals, the use of explosives has increased much due to which many adverse impacts can be seen on the structures. This also deteriorates the surrounding environment. Out of various hazards of surface mine blasting ground vibration and air over-pressure are the most damaging ones. The peak particle velocities in respect of charge per delay and distances, play a very important role. Apart from assessment of ground vibration, plotting of contour map of PPVs seems to be very important for the mine operators.

3 illus, 5 tables, 10 ref

013073   Meenakshi K;Srinivasa Rao C;Satya Prasad K (E.C.E, Dep, JNTU, Kakinada, Andhra Pradesh) : Scene based video watermarking using slant transform. IETE J Res 2014, 60(4), 276-87.

Due to the explosion of Internet and multimedia copyright protection has gained utmost importance. Digital watermarking is found to be a solution for digital copyright protection. In this paper, a robust video watermarking based on slant transform is presented. The video is partitioned into frames and owner's identity watermark is embedded in slant transform domain by modifying the transform coefficients. The transparency of the watermarked image is enhanced by embedding the watermark in selected positions based on the human visual system (HVS) weightage matrix. The robustness of the proposed algorithm is examined by subjecting the algorithm to various compressional and signal processing attacks. Peak signal to noise ratio and normalized cross correlation are computed to prove that the proposed algorithm is more imperceptible and robust.

10 illus, 2 tables, 24 ref

013072   Manivel A;Asiri A M;Alamry K A; Lana-Villarreal T;Anandan S (Nanomaterials and Solar Energy Conversion Lab, Chemistry Dep, National Institute of Technology, Tiruchirappalli-620 015, Email: sanand99@yahoo.com) : Interfacially synthesized PAni-PMo12 hybrid material for supercapacitor applications. Bull Mater Sci 2014, 37(4), 861-9.

The concept of interfacial polymerization is utilized for the synthesis of polyaniline-phospho-molybdate (PAni-PMol2) molecular hybrids and it is well characterized. The electrical conductivity of the synthesized hybrid materials increases with increase in PMo12 wt%. The synthesized hybrid materials are evaluated as the active electrode materials for supercapacitor application. Cyclic voltammetric studies of the hybrid-modified electrode shows broad parallelogram-shaped peak as an evidence for pseudo-capacitive behaviour. The galvanostatic charge-discharge studies enlighten that interfacially synthesized hybrid materials loaded with PMol2 show relatively enhanced specific capacitance values than PMo12 free samples.

7 illus, 45 ref

013071   Mandal M;Singh D;Gouthama;Murty B S;Sangal S; Mondal K (Materials Science and Engineering Dep, Indian Institute of Technology Kanpur, Kanpur-208 016, Email: kallol@iitk.ac.in) : Porous copper template from partially spark plasma-sintered Cu-Zn aggregate via dezincification. Bull Mater Sci 2014, 37(4), 743-52.

Present work deals with the preparation of spark plasma-sintered Cu-Zn aggregate (5, 10 and 20 wt% Zn) with interfacial bonding only starting from elemental powders of Cu and Zn (99.9% purity) and subsequently making of porous template of Cu by dezincification. Sintering is done so as to achieve only inter-facial bonding with the aim to maintain maximum potential difference between the Cu and Zn particles during dezincification process in various solutions, viz. 1 N HC1 and 3.5 wt% NaCl solutions. X-ray diffraction, optical microscopy and SEM-EDS are carried out to examine microstructural evolution and subsequent changes in hardness with sintering temperatures and different Zn percentages. Dezincification and pore formation are conducted on sintered 0.5 mm thick 12 mm diameter disc samples. The size, distribution and nature of pores in porous templates of Cu are then investigated using optical microscopy and SEM-EDS analysis.

11 illus, 2 tables, 26 ref

013070   Maity S R;Chakraborty S (Production Engineering Dep, Haldia Institute of Technology, East Midnapore, Haldia-721 657, Email: schakraborty@production.jdvu.ac.in) : Visual decision aid for gear materials selection. J Instn Engrs : Ser C 2013, 94(3), 199-212.

Materials play an important role during the entire design process and the designers need to identify materials with specific functionalities in order to find out feasible design concepts. While selecting materials for engineering designs from an ever-increasing array of alter-natives, with each having its own characteristics, applica-tions, advantages and limitations, a clear understanding of the functional requirements for each individual component is required and various important criteria need to be con-sidered. Although various approaches have already been adopted by the past researchers to solve the material selec-tion problems, they all require profound knowledge in mathematics from the part of the designers for their imple-mentation. This paper proposes the application of an inte-grated preference ranking organization method for enrichment evaluation and geometrical analysis for inter-active aid method as a visual decision aid for material selection. Two real time gear material selection problems are solved which prove the potentiality and usefulness of this combined approach. It is observed that Nitralloy 135M and Nylon glass fiber reinforced 6/6 are respectively the choicest metallic and non-metallic gear materials.

8 illus, 6 tables, 42 ref

013069   Londhe S D;Rao C G (Mechanical Engineering Dep, National Institute of Technology, Warangal-506 004, Email: cgr_gcr@yahoo.co.ini) : Mixed convection with conduction and surface radiation from a vertical channel with discrete heating. J Instn Engrs : Ser C 2013, 94(3), 213-23.

Numerical investigation into fluid flow and heat transfer for the geometry of a vertical parallel plate channel subjected to conjugate mixed convection with radiation is attempted here. The channel considered has three identical flush-mounted discrete heat sources in its left wall, while the right wall that does not contain any heat source acts as a sink. Air, assumed to be a radiatively non-participating and having constant thermophysical properties subject to the Boussinesq approximation, is the cooling agent. The heat generated in the left wall gets conducted along it and is later dissipated by mixed convection and radiation. The governing equations, considered in their full strength sans the boundary layer approximations, are converted into vorticity-stream function form and are then normalized. These equations along with pertinent boundary conditions are solved through finite volume method coupled with Gauss-Seidel iterative technique. The effects of modified Richardson number, surface emissivity, thermal conductivity and aspect ratio on local temperature distri-bution along the channel, maximum channel temperature and relative contributions of mixed convection and radia-tion have been thoroughly studied. The prominence of radiation in the present problem has been highlighted.

10 illus, 19 ref

013068   Linares C F;Ocanto F;Bretto P;Monsalve M (Unidad de Sintesis de Materiales y Metales de Transicion, Facultad de Ciencias y Tecnologia Departmento de Quimica, Universidad, Valencia, Ed. Carbobo, Apartado Postal 3336, Venezuela, Email: clinares@uc.edu.ve) : Study of as-synthesized and calcined hydrocalumites as possible antacid agents. Bull Mater Sci 2014, 37(4), 941-4.

A hydrocalumite-type solid was synthesized by the homogeneous co-precipitation method by using Ca and Al nitrate solutions in a basic medium (NaOH). This solid was calcined at 700 and 900 °C, respectively. Then, solids were characterized by X-ray diffraction, FT-IR spectroscopy and BET surface area measurements. Finally, these solids were tested as antacids by using a synthetic gastric juice. Results showed that calcined samples were able to neutralize the synthetic gastric juice in more extension as an as-synthesized hydrocalumite; however, the last solid showed better conditions as a potential antacid.

3 illus, 1 table, 14 ref

013067   Kundu A;Gupta B (Electronics and Telecommunication Engineering Dep, Jadavpur Univ, Kolkata, WB 700 032) : Comparative SAR analysis of some Indian fruits as per the revised RF exposure guideline. IETE J Res 2014, 60(4), 296-302.

Specific absorption rate (SAR) is used as the measure of rate at which radio frequency (RF) energy is absorbed by an object when exposed to an electromagnetic field. The word "SAR" is usually associated with the human exposure to RF/microwave energy from different electromagnetic sources and, therefore, SAR limits have been defined only for human by the government of India. ICNIRP (International Commission on Non-Ionizing Radiation Protection) RF exposure guideline was maintained in India up to 31 August 2012, and thereafter Indian government has reduced the maximum permissible RF exposure levels to one-tenth of ICNIRP guideline with effect from 1 September 2012. On the other side, the whole plant kingdom gets exposed to continuous RF electromagnetic field (24 x 7 x 365 hours a year) from cell phone towers that transmit high RF/microwave power for radio coverage. High permittivity and loss parameters are observed in most plants, fruits and vegetables due to high water content and ionic concentration. Therefore, it is strongly expected that the plants, fruits and vegetables are also absorbing a huge amount of RF/microwave energy which might have some effects on their growth. Hence, the prime objective of this research is to find out the RF power absorption level in terms of SAR evaluation of some native fruits as per the revised Indian RF exposure guideline, particularly in GSM 900 and GSM 1800 MHz bands along with Wi-Fi 2400 MHz band at public exposure zone.

5 illus, 7 tables, 8 ref

013066   Kruthiventi S;Basavakumar K G;Nambala S; Subramanyacharyulu G (NO, L.B. Reddy College of Engineering, Mylavaram, Andhra Pradesh, Email: satyasai222@gmail.com) : Influence of heat treatment on microstructural and mechanical properties of nodular cast iron. J Instn Engrs : Ser D 2014, 95(1), 75-9.

Spheroidal Graphite Iron (SG Iron) is popularly known as ductile iron or nodular cast iron which is a special case of cast iron having carbon content of more than 3 wt% in volume and graphite is in the form of spherical tiny sized particles. Since the last three decades, the demand for SG Iron has been increasing due to its superior mechanical properties such as high strength and toughness, this nature leads to the usage of SG Iron in numerous industrial applications. From the earlier studies, it has been proved that addition of alloying elements to SG Iron leads to change in properties such as increased tensile strength and hardness. Heat-treatment of alloys is one of the valuable methods to achieve better properties. In the present study, the microstructures and mechanical properties of SG Iron were studied after various heat treatments beyond the limits, and tests were done to measure its mechanical properties like tensile strength, hardness, impact strength. Digital microphotographs, scanning electron microphotographs were analysed before and after the heat treatment. Results indicated great change in mechanical properties after the heat-treatment. From the results it can be concluded that the heat treatment of SG Iron results in changed composition of alloys, which also leads to economical growth of SG Iron.

10 illus, 3 tables, 9 ref

013065   Jinnah M A (NO, Islamic Univ of Technology (IUT), BoardBazar, Gazipur 1704, Bangladesh, Email: jinnah@iut-dhaka.edu) : Numerical simulation of shock induced turbulence in a nozzle flow. J Instn Engrs : Ser C 2013, 94(3), 229-37.

In the present paper, a study has been conducted to investigate the shock induced turbulent flow fields and shock/turbulent-boundary layer interaction at the nozzle divergent. Experimental photographs and numerical images are used to investigate on laminar flow structures, transition phenomena, flow separation line as well as vis-cous boundary layer separation, turbulence structure development and shock/turbulent-boundary layer interac-tion. It is observed that transition from laminar to turbulent flow separation is shown earlier at the nozzle divergent for the weaker shock wave propagation and the fully devel-oped turbulence is appeared with unsteady flow fluctua-tions at the end of the nozzle divergent. It is found that the pressure downstream of the separation point showed an unsteady behavior with strong oscillations, and finally jumped to values quite above the ambient pressure. By solving the 2D Navier-Stokes equations with k-ε turbulence model, all turbulent parameters are determined at the end of the nozzle divergent and it is observed that turbulence intensities are almost uniform at the end of the nozzle divergent where slight decay phenomena are appeared along the downstream direction. The skewness of the velocity fluctuations indicates that the present flow appears to be isotropic at the end of the nozzle divergent.

8 illus, 25 ref

013064   Jagdeep Kaur;Sharma M;Pandey O P (School of Physics and Materials Science, Thapar Univ, Patiala-147 004, Email: oppandey@thapar.edu) : Synthesis, characterization, photocatalytic and reusability studies of capped ZnS nanoparticles. Bull Mater Sci 2014, 37(4), 931-40.

This paper presents results of a study on the structural and morphological properties of 2-mercaptoethanol (2-ME) capped ZnS nanoparticles (NPs). The photocatalytic and reusability study of the synthesized NPs to degrade dyes was also done. ZnS semiconductor NPs were synthesized via chemical precipitation route using 2-ME as a stabilizing agent. The as-prepared NPs were characterized by X-ray diffraction (XRD) technique to confirm the nanometer sized particle formation. Morphological features of capped ZnS NPs were determined by transmission electron microscopy (TEM). Dynamic light scattering (DLS) technique was used to determine the hydrodynamic size of capped ZnS NPs. UV-Vis studies were done to determine the absorption edge and bandgap of the capped ZnS NPs. Fourier transform infrared spectro-scopy (FT-IR) studies were done to confirm the presence of 2-ME on the surface of NPs. Photocatalytic studies of the as-prepared ZnS NPs were done by taking Ponceau S and crystal violet dyes as model pollutants. Their comparative degradation behaviour has been discussed. Reusability study of ZnS NPs was done to ensure its applicability as recycled catalyst in photocatalysis. The result showed photocatalytic enhancement of reused catalyst. Possible reason has been discussed in this work.

13 illus, 2 tables, 34 ref

013063   Hari Gopi K;Gouse Peera S;Bhat S D;Sridhar P; Pitchumani S (NO, CSIR-Central Electrochemical Research Institute-Madras Unit, CSIR Madras Complex, Chennai-600 113, Email: sdbhatcecri@gmail.com) : 3-methyltrimethylammonium poly(2,6-dimethyl-1,4-phenylene oxide) based anion exchange membrane for alkaline polymer electrolyte fuel cells. Bull Mater Sci 2014, 37(4), 877-81.

Hydroxyl ion (OH) conducting anion exchange membranes based on modified poly (phenylene oxide) are fabricated for their application in alkaline polymer electrolyte fuel cells (APEFCs). In the present study, chloromethylation of poly(phenylene oxide) (PPO) is performed by aryl substitution rather than benzyl substitution and homogeneously quaternized to form an anion exchange membrane (AEM). ^{1H NMR and FT-IR studies reveal successful incorporation of the above groups in the polymer backbone. The membrane is characterized for its ion exchange capacity and water uptake. The membrane formed by these processes show good ionic conductivity and when used in fuel cell exhibited an enhanced performance in comparison with the state-of-the-art commercial AHA membrane. A peak power density of 111 mW/cm2 at a load current density of 250 mA/cm2 is obtained for PPO based membrane in APEFCs at 30 °C.}

4 illus, 1 table, 23 ref

013062   Gupta R C;Gupta A K;Shrivastava R K (Civil Engineering Dep, Govt. Polytechnic College, Ujjain, Madhya Pradesh) : Water quality modelling of a stretch of river kshipra (India). Nat Envir Pollut Technol 2013, 12(3), 511-16.

River Kshipra is receiving a large volume of untreated sewage daily in its stretch of Ujjain city and the status of water is pathetic during low flow season. A stream water quality model QUAL-2Kw was used in the present study to simulate the contributions from different sources and sinks of dissolved oxygen and to understand the interactions among them. The model was calibrated and validated and the simulated results are in general agreement with measured water quality in River Kshipra. It was established through this study that the QUAL-2Kw model can be used for future river water quality management options for River Kshipra with reasonable accuracy.

6 illus, 1 table, 16 ref

013061   Guchhait S K;Dewan S;Saha J K;Mitra P K (Metallurgical & Material Engineering Dep, Jadavpur Univ, Kolkata-700 032, Email: sujitguchhait.chem@gmail.com) : Recreation of marine atmospheric corrosion condition on weathering steel in laboratory. J Instn Engrs : Ser D 2014, 95(1), 43-7.

Salt spray test, autoclave corrosion test, SO₂ salt spray test, and Relative humidity test are generally used to assess atmospheric corrosion in laboratories at accelerated rates. However, no test can absolutely simulate the service condition. One can get only approximate corrosion rates using the aforesaid tests which serve as an indicative of corrosion behavior of the material in a service condition. The present work is aimed at creating specific environmental condition in laboratory to get the corrosion test done in short duration to compare with on field exposure test which would otherwise take years to complete. In this work recreation of atmospheric environment of Digha was tried and it was simulated in such a manner that the results of laboratory test could be compared with long time field exposure at Digha. Weathering steel (WS) was taken for experimentations. Potentiostatic electrochemical tests route was adopted to simulate atmospheric condition of Digha. Laboratory test results compared well with 18 month field exposure data in terms of corrosion rate, SEM arid Ramon Spectroscopy matching.

8 illus, 5 tables, 16 ref

013060   Gitizadeh M;Ghavidel S;Aghaei J (Electronics and Electrical Engineering Dep, Shiraz Univ of Technology, Shiraz, Iran) : Using SVC to economically improve transient stability in long transmission lines. IETE J Res 2014, 60(4), 319-27.

The aim of this paper is to select the optimal size, location, and parameter setting of static var compensator (SVC) to improve power system stability in long transmission lines. Two objectives are considered in this paper to improve both the transient stability of the system and the SVC investment cost. In this study, the actual model of the long transmission line is considered to accurately determine the SVC location. By using the actual model of the line for long transmission lines, the SVC investment cost is reduced and the results have more accuracy than that found when the simplified model was used. In addition to placement of SVC for improving the system transient stability, an extra controller is used and adjusted to enhance the performance of the SVC. The problem is formulated as a form of multi-objective function and then multi-objective particle swarm optimization (MOPSO) is used to solve the problem and find the solution. In this research, results are presented as a set of responses to help the decision maker choose the appropriate response. A two-area test system with long transmission line is used to show the effectiveness and efficiency of the proposed method. The results of the non-linear simulation show that the optimum sizing, siting, and parameter setting of SVC can improve greatly the system's transient stability and reduce the SVC investment cost.

8 illus, 1 table, 30 ref

013059   Ghosh D;Shukla A K;Roy H (NDT & Metallurgy Group, CSIR-Central Mechanical Engineering Research Institute, Durgapur-713 209, Email: dghosh@cmeri.res.in) : Nano structured plasma spray coating for wear and high temperature corrosion resistance applications. J Instn Engrs : Ser D 2014, 95(1), 57-64.

Nano structured coating is a major challenge today to improve the different mechanical properties, wear and high temperature corrosion resistance behaviour of different industrial alloys. This paper is a review on synthesis of nano powder, plasma spraying methods, techniques of nano structured coating by plasma spray method, mechanical properties, tribological properties and high temperature corrosion behaviour of nano structured coating. Nano structured coatings of ceramic powders/composites are being developed for wide variety of applications like boiler, turbine and aerospace industries, which requires the resistance against wear, corrosion, erosion etc. The nano sized powders are subjected to agglomeration by spray drying, after which nano structured coating can be successfully applied over the substrate. Nano structured coating shows improved mechanical wear resistance and high temperature corrosion resistance. The significant improvement of wear and corrosion resistance is mainly attributed to formation of semi molten nano zones in case of nano structured coatings. The future scope of application of nano structured coating has also been highlighted in this paper.

4 illus, 62 ref

013058   Gazanfari M;Karimzadeh M;Ghorbani S;Sadeghi M R;Azizi G;Karimi H;Fattahi N;Karimzadeh Z (Chemistry Dep, Imam Hossein Univ, P.O. Box 16535-187, Tehran, Iran, Email: morteza.karimzadeh@ch.iut.ac.ir) : Synthesis of aluminium nanoparticles by arc evaporation of an aluminium cathode surface. Bull Mater Sci 2014, 37(4), 871-6.

Aluminium nanoparticles (Al Nps) are synthesized using arc discharge method by applying direct current between aluminium electrodes in liquid environment without any use of vacuum equipment, heat exchangers, high temperatures furnaces and inert gases. After synthesis of Al Nps, in situ coating process on the nanoparticles was performed immediately. The effects of media on the yield and morphology of aluminium nanoparticles were investigated. Analysis result of the samples indicated that particle size was less than 30 nm, when 120 A/cm^{2 arc current was used. In addition, coating agent can affect arc velocity, arc stability, morphology and composition of the nanoparticles. Resultant nanoparticles were identified using X-ray powder diffraction (XRD), also their surface morphology was studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and finally the accuracy of coating was assessed with infrared (IR) spectroscopy.}

9 illus, 21 ref

013057   Garay-Reyes C G;Hernandez-Santiago F; Cayetano-Castro N;Martinez-Sanchez R;Hernandez-Rivera J L; Dorantes-Rosales H J;Cruz-Rivera J J (Universidad Autonoma de San Luis Potosi, Instituto de Metalurgia, Sierra leona 550, Col. Lomas 2 seccion, 78210 SLP, Mexico, Email: garay_820123@hotmail.com) : Analysis of ostwald ripening in Ni-rich Ni-Ti alloys by diffusion couples. Bull Mater Sci 2014, 37(4), 823-9.

The coarsening kinetics of γ' precipitates in Ni-rich Ni-Ti alloys are studied using a Ni-11.5 wt% Ti and pure Ni diffusion couple. The formed concentration gradient allowed to study the aging process at 1023 K (750 °C) in Ni-rich Ni-Ti alloys with Ti content from 8.62 to 11.15 wt% Ti. In general, during the coarsening of γ precipitates, the experimental coarsening kinetics do not fit well to the LSW or TIDC theoretical models and anomalous behaviour of coarsening rate constant (k_r) associated with γ' volume-fraction is confirmed at high values.

6 illus, 1 table, 44 ref

013056   Gangele A;Ahmed S (NO, Maulana Azad National Institute of Technology, Bhopal, Madhya Pradesh, Email: aparna.gangele@gmail.com) : Modal analysis of S809 wind turbine blade considering different geometrical and material parameters. J Instn Engrs : Ser C 2013, 94(3), 225-8.

In recent years wind energy has been the world's fastest growing source of energy. The wind turbine industry is booming and is spending a lot on research for improving the performance of its present machines and increasing their capacity. The purpose of this paper is to investigate the dynamic behavior characteristic of 1.5 MW wind turbine system (WTS) and carries out the analysis considering different geometrical and material parameters. Vibration of the blade of the WTS on the flap and edge section of the blade that is one of the most important elements of dynamic characteristic of WTS is evaluated. Natural frequency and mode shape are calculated by the finite element analysis, with commercial program (ANSYS). The results are compared which are performed by the finite element analysis with commercial FEM program (ANSYS) on the basis of the natural frequency and mode shape.

6 illus, 4 tables, 8 ref

013055   Fu F;Zhai J;Xu Z;Shen B;Yao X (NO, Luoyang Institute of Science and Technology, Luoyang 471023, China, Email: apzhai@tongji.edu.cn) : Grain growth kinetics of textured-BaTiO₃ ceramics. Bull Mater Sci 2014, 37(4), 779-87.

Textured BaTiO₃ (BT) ceramics were fabricated by templated grain growth method. Effects of sintering conditions on the grain growth process of textured-BT ceramics were investigated. Orientation degree increased initially and then decreased with increasing soaking time. The ceramics were composed of equiaxed matrix grains and brick-like template particles. The brick-like particles aligned parallel to the casting direction by observing from SEM images. A (h00)-preferred orientation was confirmed by SAED and XRD patterns. Mechanism of grain growth in textured-BT ceramics was studied. Both consumption of matrix by templates and grain growth of templates determined the orientation degree of ceramics. The kinetic mechanism for grain orientation was also discussed by the simplified phenomenological kinetic equation. The average activation energies were 364 kJ/mol for matrix grain and 918 kJ/mol for template particle, respectively. Finally, a dense ceramic with 85% grain orientation was obtained after sintering at 1400 °C for 2 h.

13 illus, 2 tables, 31 ref