002789   Singh D;Agerwal R K (Mechanical Engineering Dep, KITE College, Sitapura, Jaipur) : Exhaust of a diesel engine thermal storage. Int J latest Technol Engng Mgmt appl Sci 2012, 1(10), 115-44.

Exhaust gas which occurs as a result of the combustion of fuels such as natural gas, gasoline/petrol, diesel, fuel oil or coal. It is discharged into the atmosphere through an exhaust pipe or flue gas stack. The main objective of the proposed project is to utilize heat from the exhaust gases of a diesel engine and convert heat to useful work. Energy supplied to an engine is the heat value of the fuel consumed. But only a part of this energy is transferred into useful work. From heat balance sheet of a typical CI engine we find out that the total heat loss is around 33-45, of which 33 is due to exhaust gases and the rest is lost to the surroundings. Reducing this figure to 10, then it will be a substantial contribution.

9 illus, 3 tables, 10 ref

002788   Shaktawat N;Sharma M;Chaudhary A K (EEE Dep, M.I.T., Mandsaur, Madhya Pradesh, Email: neha.shaktawat18@gmail.com) : Modeling & simulation of passive shunt filter for power quality improvement using TCR and TSC combination by MATLAB/simulink. Int J latest Technol Engng Mgmt appl Sci 2012, 1(10), 65-71.

Power system harmonics are a menace to electric power system with disastrous consequences. The line current harmonics causes increase in losses, instability, and also voltage distortion. This paper presents the combination of passive shunt filters with Thyristors-Controlled Reactor (TCR) and Thyristor Switch Capacitor (TSC) using MATLAB /Simulink are designed and analyzed to improve the power quality at AC mains. Both passive and active filters have been used near harmonic producing loads or at the point of Common coupling to block current harmonics. Shunt filters still dominate the harmonic compensation at medium/high voltage level, whereas active filters have been proclaimed for low/medium voltage ratings. With diverse applications involving reactive power together with harmonic compensation, active filters are found suitable. One of the way out to resolve the issue of reactive power would be using filters and TCR, TSC with combination in the power system.

15 illus, 2 tables, 11 ref

002787   Shabanlou S;Rajabai A (Water Engineering Dep, Kermanshah Branch Islamic Azad Univ, 8247901, Kermanshah, Iran, Email: saeid.shabanlou@gmail.com) : Evaluation of empirical relationships to estimate instantaneous peak flood discharge in Iran. Ecol Envir Conserv 2011, 17(2), 183-90.

One of the most important parameters in design of hydraulic structures is the instantaneous peak discharge. In this research, 20 empirical formulae that have been developed all over the world to estimate the peak discharge are use in some hydrologic stations of western watersheds of Iran. Concurrent peak discharge data during a 42 years period at some stations were selected, flood frequency analysis was performed on these peak discharges by 8 probability distribution functions and after the best fit test, the peak discharges with return periods of 2, 5,10, 25, 50,100, 500 and 1000 year were estimated by Log Pierson type 3 distribution. By comparing the coefficient of determination, standard error, mean error and residuals graph for each return period, the best formula was recommended. The comparison between estimated and measured peak discharges showed that model no. 2 has the maximum error (114.75%) and model no. 12 has the minimum error (22.58%). For the recommended models, the mean error for 2 to 1000-year return periods was between 21.67% to 34.67%.

2 illus, 3 tables, 26 ref

002786   Samimi A (Young Researchers Club, Central Tehran Branch, Islamic Azad University, Tehran, IRAN, Email: amirsamimi1161@gmail.com) : Investigation of corrosion metal in oil industry in Iran. Bull pure appl Sci-Sect D 2012, 31(2), 225-31.

Erosion is one of the important unlikely problems in oil refining industry that produces many damages and values to refining parts. In other part stop of refining operation for repairing is very expensive. Many erosions are happened in refining operations when equipments are placed to atmosphere, Powerful acids, eruption gases, hydrocarbon vampires and high temperature make very complex situation in oil refining industry, Monotonous erosion, cavity erosion rubbing erosion, stress split are more common erosions in oil refining systems that will be search in this survey.

17 ref, 3 illus

002785   Saltik M B;Giri D K (Electrical and Electronics Engineering Dep, Middle East Technical University, Ankara, Turkey, Email: judipakkumar@gmail.com) : Design and simulation of LQR controller with the double inverted pendulum driven by linear induction motor. Int J Comp Applic 2011, 6(1), 61-6.

Proposes a design and simulation of LQR controller for a double inverted pendulum system, consisting of a two-link pendulum mounted on a cart. The cart is moved by a linear induction motor. The controller achieves the aim by moving the cart the back and forth on a rail on limited length by applying the appropriate of force. It is shown that the angles of double inverted pendulum turns back to its upright position and also at the same time the cart displacement will be at zero position with the appropriate disturbance force. The expectations are agrees with our simulation results. The simulation results shows that the double inverted pendulum mounted on a cart can be controlled with the designed LQR controller.

5 illus, 1 table, 11 ref

002784   Razmara P;Shabanlou S (Civil Engineering Dep, Hamdan Branch Islamic Azad Univ, Iran) : Estimation of erosion intensity and sediment yield in the gorganrood watershed. Ecol Envir Conserv 2011, 17(4), 803-9.

For Estimation of erosion and its potential of sedimentation in basin without data, several models have been presented. One of these models that have more application with appropriate result in IRAN is the MPSIAC model. In the Recent models the role and impact of 9 important and effective factors in water erosion were assessed and rated and finally a total score was obtained by affecting factors on erosion (degree of sedimentation) in each unit (geomorphology) and total areas of research, Sedimentation rate in the basin be estimated with revised MPSIAC model. In most cases, in Iran imported model without applying the regional coefficients are used. In this study it is to compare estimated sediment using MPSIAC model and observational method, the rate of accuracy and applicability of model in Golestan watershed. The result of this calculation shows that Gholi Tape sub-basin has minimum and Gorganrood sub-basin to Hajighoshan sediment survey station has maximum sediment load.

2 illus, 3 tables, 6 ref

002783   Prasad D;Asim Kumar;Pathak K K;Madan Jee (M I T, , Muzaffarpur, Bihar, India) : Magnetic properties of azafullerence C_59> polymes and the single wall carbon nanotubes. Bull pure appl Sci-Sect D 2012, 31(2), 187-9.

Author theoretically studied that the impurity state lies in the middle of the gap of the azafullerence C₅₉₅₉N by electron spin resonance, which showed that the spin density does not decrease monotonically with distance from N. The spin density due to the lone orbital was not well localized to the nearest C. In the case of dimer the N atoms were found to be trans to each other.

5 ref, 2 illus

002782   Parvishi A;Musavi Jahromi S H;Shafal Bajestan M (Agriculture and Natural Resources Dep, Islamic Azad Univ, Science and Research Branch, Tehran, Iran, Email: a.parvishi@gmail.com) : Evaluation of scour below ski jump bucket of spillway in submerged condition. Ecol Envir Conserv 2011, 17(4), 661-4.

The paper briefly explains the effect of hydraulic conditions of flow and lip angle on depth of scour. The obtained results show that the depth of scour affect greatly by the rate of the discharge and the depth of tail water. The lip angle plays an important role in characteristics of the occurred scour. Experimental results showed that the lip angle of 450 is the optimum angle which gives minimum longitudinal area of the scour hole. Also, validation of selected equations for predicting maximum scour depth at below of the ski jump bucket of spillway showed that the equation proposed by Schoklitsch gave minimum error (35%).

8 illus, 2 tables, 10 ref

002781   Pareek M (NO, ARCO Industries, Mumbai, Email: pareekmanish2@gmail.com) : Solar photovoltaic cell. Int J latest Technol Engng Mgmt appl Sci 2012, 1(10), 184-9.

Concentrating solar power (CSP) is a power generation technology that uses mirrors or lenses to concentrate the sun's rays and, in most of today's CSP systems, to heat a fluid and produce steam. The steam drives a turbine and generates power in the same way as conventional power plants. Other concepts are being explored and not all future CSP plants will necessarily use a steam cycle.

9 ref

002780   Narshimhan H S;Patil V P (Civil Engineering Dep, Hassan Malnad College of Engineering Hassan, Karnataka, Email: narashimhan_hs@yahoo.co.in) : Analytical response of concrete filled steel tubular column under axial loads. Int J Envir Dev 2012, 9(2), 175-83.

The constitutive model in this paper addresses the behavior of Concrete filled steel tubular column on the compressive response due to axial loads. Three-dimensional nonlinear finite element models are developed to study the force transfer between steel tube and concrete core. The nonlinear finite element program ABAQUS 6.8 is used. The interaction between steel tube and concrete core is the discussing issue for understanding the behavior of concretefilled steel tube columns (CFST). The elasro-plastic model is based on the Drucker-Prager yield criterion. A comparison of experimental failure loads with the predictedfailure loads in accordance with the method described in Euro code Part-4 showed good agreement for axially loaded columns.

5 illus, 14 ref

002779   Munirathnam N R;Srinivasa Rao K;Prakash T L (Centre for Materials for Electronics Technology (C-MET), IDA Phase-III, Cherlapally, HCL (P.O.), Hyderabad-500 051, Email: rathnam1960@gmail.com) : Purification of cadmium by selective volatilization in vacuum in presence of oxide phase on its melt. Bull Mater Sci 2012, 35(2), 163-7.

Purification of cadmium in the presence of a thin (<126>0.001 mm) oxide layer on the surface of the molten metal was carried out using a simple system designed and fabricated locally. The analytical results revealed that the distillation through oxide layer gave better separation for Co, Ni, Cu, Zn, Ag, Sn, Hg and Tl, when compared to the distillation without oxide layer. This was attributed due to the impurity metal oxide phases formation on the surface of the molten metal. The influence of oxygen flow time on the distillation rate of cadmium was established. There was no excess oxygen (O) retained in the distillate after two consecutive vacuum distillations through oxide route. The experiments were conducted at the level of nearly 1.5 kg a batch to study the impurities behaviour due to upscaling. The detailed chemical analysis of 58 impurity elements in Cd in presence and absence of oxide layer was carried out by glow discharge mass spectrometry (GDMS).

2 illus, 2 tables, 13 ref

002778   Mukherjee S;Roy S;Sayantani A;Chayan B (Automobile Engineering Dep, MCKV Institute of Engineering, Kolkata, Email: sayantan.akash@gmail.com) : Embedded system based multi-purpose helmet technology. Int J Comp Applic 2011, 6(1), 7-13.

Mobility is an essential requirement for any type of meaningful involvement in our modern society. Intelligent Transportation Systems (ITS) improve transportation safety & mobility to enhance productivity through the use of advanced communication technologies and their integration into the transportation infrastructure and in vehicles. The significant rise in the number of two wheelers is happened during last decade in turn, increased the number of accidents involving two-wheelers. The most striking thing researchers have found studying the vehicle crash statistics and motorcycle injuries is that a large number of motorcycle accidents occurred due to the road user's fault viz. the lesser use of helmets, drunk driving, drowsy biking, inattentive biking etc. The paper aims to suggest an Intelligent Transportation System for two wheelers. A technology is embedded in an ordinary full faced helmet that makes helmet wearing a must. Additionally it helps in alerting drowsy, inattentive two-wheeler drivers, minimizes to some extent fuel wastage and rash driving.

9 illus, 27 ref

002777   Mukherjee S (Geography Dep, Nafar Ch. Academy, Howrah, West Bengal) : Growing need of risk assessment and its implication in Eastern coalfields. Indian J Landsc Syst ecol Stud 2012, 35(2), 148-56.

Coal mining is a dangerous business, but Burning coal generates about half of the country's electricity. Coal was also a major factor in catapulting the nation into the Industrial Age, However, over the years miners have often suffered injury and even death from the many hours of hard labor and dangerous working conditions. Mining is much safer today than it used to be. Mining is a perilous occupation to pursue because the miners are sometimes killed by the pestilential air which they breathe; sometimes their lungs rot away; sometimes the men perish by being crushed in masses of rock; sometimes falling from ladders into the shafts, they break their arms, legs, or necks; and it is added, there is no compensation which should be thought great enough to equalize the extreme dangers to safety and life. From the decision to invest in a new mine to the decision to go underground to work in an operating mine, there is risk. The main purpose of risk assessment is to determine whether planned or existing control measures and adequate. The intention is that risks should be controlled before harm could occur. For many years risk assessments have been carried out mainly on an informal basis. It is now recognized that risk assessments are the keys foundation for management and systematic procedures are necessary to ensure their success.

3 illus, 2 table, ref

002776   Moyra S K (NO, Jangipara M.N. Mahavidyalaya, West Bengal) : Review of engine van industry related problems- a case study on Ganeshbati mouja, Jangipara block, Hugli district, West Bengal. Indian J Landsc Syst ecol Stud 2012, 35(2), 198-204.

Now a day's a peculiar looking transport vehicle is easily noticeable if someone go a little bit away from the main cities and towns of West Bengal. The suburban and rural roads are very quickly crowding with such illegal vehicle, locally named as Engine van. These vehicles are manufactured from various workshops, manufacturing units and engineering industries scattered in the important rural market areas of south Bengal. Present study is undertaken on one of such rural market area. Prime purpose of this study is to identify various problems associated with the emergence of such typical, non government permitted, highly profit making Engine van industry. It is also to find out the major linkages and interactions of such industry with its place of existence. Socio-economic status of the people of the study area is also depicted during the course of making this paper. An attempt has been also made to bring out the disparity in the distribution of profit. Promotion of this industry is admirable only when it is legally sanctioned by government.

2 illus, 5 ref

002775   Mhaisagar Y S;Joshi B N;Mahajan A M (Electronics Dep, North Maharashtra Univ, Jalgaon-425 001, Email: ammahajan@nmu.ac.in) : Surface texture modification of spin-coated SiO₂ xerogel thin films by TMCS Silylation. Bull Mater Sci 2012, 35(2), 151-5.

The SiO₂ xerogel thin films were deposited successfully by sol-gel technique via the acid-catalyzed hydrolysis and condensation of tetraethylorthosilicate (TEOS) with ethanol as a solvent. Further, the deposited thin films were treated wet chemically by trimethylchlorosilane (TMCS) and hexane solution with 10% and 15% volume ratio to remove the hydroxyl groups from the surface of deposited SiO₂ thin films. These as deposited and surface-modified films were characterized by ellipsometer, Fourier transform infrared (FTIR) spectrometer and contact angle meter. The presence of 2900 and 850 cm^-1 peaks of CH₃ vibrations in FTIR spectra of surface-modified films confirms the hydrphobisation of SiO₂ surface. The maximum contact angle of 108-7° was observed for the surface-modified film at 10% TMCS.

6 illus, 2 tables, 13 ref

002774   Meena R;Shukla S (NO, Regional College for Education Research & Technology, Jaipur) : Backstepping controller for magnetic levitated ball siso system and inverted pendulum mimo system using kalman filter approach. Int J latest Technol Engng Mgmt appl Sci 2012, 1(10), 97-101.

In this paper, the nonlinear backstepping design controller with a velocity observer is proposed for trajectory tracking control of magnetic ball and stabilized the inverted pendulum, where only the position measurement is available for control. Therefore, k-filter, a velocity observer is employed to compensate the external disturbance and model mismatch and estimate the unknown state variables of the system. The inverted pendulum is a highly nonlinear and open-loop unstable system. This means that standard linear techniques cannot model the nonlinear dynamics of the system therefore backstepping technique is used to control the inverted pendulum. The design uses the backstepping nonlinear control to make the ball able to track an output signal, a vertical position from some reference point, to a continuous twice differentiable positive reference signal r, asymptotically. Furthermore, some simulation results are given to illustrate the excellent performance of the backstepping control design scheme applied to SISO and MIMO systems.

7 illus, 10 ref

002773   Malik H;Jarial R K;Husain Z (Electrical Engineering Dep, NIT Hamirpur-177 005, , Email: hasmat.malik@gmail.com) : Investigating causes detection of failures in transformers. Int J Comp Applic 2011, 6(1), 67-74.

A transformer is the most important equipment for power supply to consumers. For uninterrupted power supply to consumers proper maintenance particularly preventive maintenance is very much necessary. The failure in magnetic, electric and dielectric circuits as well as structural failure may cause extensive damage to the equipment and surroundings. Proper operation and maintenance procedure may help to prevent failure and extend life of operation of the transformer. Continuous monitoring to health of the transformer and analyzing the history of past failures may indicate the type of maintenance required & facilitate identifying incipient faults. An overview of recently developed mythologies has been covered in the present paper along with planned strategy for curbing catastrophic failures creeping In service- transformers. The methods suggested in the paper are helpful in reducing failure and extending life of both the power transformers & distribution transformers.

5 illus, 1 table, 18 ref

002772   Maity J;Chattopadhyay B C;Mukherjee S P (NO, Meghnad Saha Institute of Technology, Kolkata-700 150) : Behaviour of different types of sand randomly mixing with various Natural Fibers. J Instn Engrs : Ser A 2013, 93(2), 97-104.

For rapid expansion in transportation sector in India, a huge amount of construction of roads are being made through different schemes, Such constructions require massive quantity of conventional good bricbats for sub-base construction, But due to scarcity of raw materials for construction of good bricks and dearness of energy to make bricks, use of alternate materials for making sub-base is becoming more obligatory. In such condition, use of natural sands is being advocated, To improve the properties of such sands, to suit subbase characteristics, some natural fibers like jute, coif or Sabai grass can be used in random mixing with these sands, with the aim to increase the strength and decrease in deformability of the laid subbase layer. This work highlights the usefulness of construction of sub-base with sand and natural fibers composite system, as alternate material of construction.

20 illus,4 tables, 17 ref

002771   Madan Ananda Kumar L;Lopoyetum S K (Mechanical Engineering Dep, K.Ramakrishnan College Engineering, Samayapuram, Tiruchirappalli-621 112, Email: madan324@gmail.com) : CFD analysis of solar chimney for enhanced ventilation in summer and winter. Ecol Envir Conserv 2011, 17(1), 153-62.

Today in India and the entire world, electrical energy utilization in space ventilation dominate the fields of commercial and House hold utilities. HVAC system consumes more electrical energy, and it is believed that electrical energy will be costly and scarce in the near future. Therefore alternative energy sources use will become mandatory and even more common in the coming decades. Here, Energy reforms is the need of the hour. Subsequently, solar energy is a completely natural, renewable energy applicable in all most where electrical energy is used. Furthermore, solar energy utilization is actually reducing major greenhouse gases in the atmosphere. Hence, it is a boon in mitigating global warming and creates carbon free economy. This study is concerned with the design of a solar chimney to induce ventilation in a building by using CFD model. In this study CFD (GAMBIT and FLUENT) techniques were utilized to assess the impact of inclination angle and gap between glass cover and insulated absorber. It was found that, for a south-facing chimney, an inclination angle of 50ø from the horizontal was optimum for the location of Tiruchirappalli (Longitude +78.69E, Latitude +10.81) giving greater efficiency than the vertical chimney by using a Black coated aluminum wall surface. In both summer and winter seasons comparing with vertical chimney the height of inclined chimney is having 25% less structure height and there is no variation in efficiency between them.

4 illus, 4 tables, 6 ref

002770   Lodhi S S;Singhal P K (Electronics Dep, Madhav Institute of Technology and Science, Gwalior, Madhya Pradesh, Email: sslodhi1988@gmail.com) : Design of triple band microstrip yagi uda antenna. Curr Trends Inf Technol 2013, 3(2), 7-10.

Microstrip yagi uda antenna with triple band is proposed in this paper. The design antenna consists of CPW feeding in which the ground plane and the yagi antenna are on the same plane. The resonating frequency of design antenna is 6.29, 7.97 and 9.26 GHz. The antenna had achieved the directivity of 5.232, 5.704 and 6.062 dBi. The impedance of antenna is completely matched at all the three resonating frequency. The triple band microstrip yagi uda antenna was simulated by Computer simulation technique (CST) MW studio software.

6 illus, 1 table, 7 ref

002769   Kusre B C;Shyamjai Singh (College of Agricultural Engineering and Post Harvet Technology, Central Agricultural University, Ranipool, Gangtok-737135, Email: kusrebharat@gmail.com) : Frequency analysis of different time series rainfall at Kohima, Nagaland, India. J Instn Engrs : Ser A 2013, 93(2), 105-9.

Present study was taken up with the objective of identifying suitable probability distribution function for estimating the rainfall amounts for different return period and probabilities for Kohima station in Nagaland. Five different distribution functions were selected for different data series. The distribution functions considered were normal, log normal, gumbel, log logistic and exponential. The criteria for selecting the distribution functions were coefficient of determination (R2) and Chi square values. The data series considered were annual, maximum weekly (29th calendar week), maximum monthly (July), minimum monthly (December) and monsoon season (June-September). The study revealed that log logistic distribution function was fitted well for annual, July month and monsoon season data series where as exponential data series fitted well for maximum weekly and December data series. Based on the identified frequency distribution function rainfall amounts for different return periods and probabilities were estimated.

1 illus, 5 tables, 14 ref

002768   Kothai V;Rajeev Ranjan (Materials Engineering Dep, Indian Institute of Science, Bangalore-560 012, Email: rajeev@materials.iisc.ernet.in) : Synthesis of BiFeO₃ by carbonate precipitation. Bull Mater Sci 2012, 35(2), 157-61.

Magnetoelectric multiferroic BiFeO₃ (BFO) was synthesized by a simple carbonate precipitation technique of metal nitrate solutions. X-ray powder diffraction and thermo-gravimetric analysis (TGA) revealed that the precipitate consists of an intimate mixture of crystalline bismuth carbonate and an amorphous hydroxide of iron. The precipitate yielded BiFeO₃ at an optimal calcination temperature of <126>560°C. Energy dispersive X-ray (EDX) analysis showed 1:1 ratio between Bi and Fe in the oxide. X-ray photoelectron spectroscopy (XPS) studies confirmed that Fe to be in +3 oxidation states both in the precipitated powder and BiFeO₃. The synthesized BFO exhibits a very weak ferromagnetic correlation at room temperature and the degree of which increases slightly on cooling down to 10 K suggesting alteration in the long range spatial modulation of the spins arrangement as compared to the bulk BiFeO₃.

8 illus, 21 ref

002767   Khan P;Singh H (Electrical Engineering Dep, MITS, Gwalior, Email: parvejkhan4834@gmail.com) : Power flow comparisons in a transmission line with UPFC and SSSCs devices. Int J latest Technol Engng Mgmt appl Sci 2012, 1(10), 102-7.

The device SSSCs work in the same way as the STATCOM. It has a voltage source converter (VCS) connected in series to the transmission line through a transformer. It required an energy source to provide a continuous voltage through a condenser and to compensate the losses of the VSC. A SSSC is able to exchange active and reactive power with the transmission system. In this case the serial injected voltage can delay or advanced the line current. This means that the SSSC can be uniformly controlled in any value. In this paper the result thus we obtained by modeling a transmission system in MATLAB SIMULINK by using UPFC and SSSCs (static synchronous series compensator) in first case the upfc is connected to bus B3 and in second case upfc is replaced by sssc and the result obtained from these two case is compared. From these two simulink results we conclude that the sssc gives more suitable results as compared to UPFC.

4 illus, 11 ref

002766   Kavitha A;Rajamani V;Anandha Kumar P (NO, PSNA College of Engineering and Technology, Dindigul-624 622, Email: kavivenkat99@gmail.com) : Performance eveluation of delay in optical packet switching using various traffic patterns. Curr Sci 2011, 101(11), 1462-7.

Delay is an important parameter in optical packet switching networks and it affects the performance of the network. In this communication, a mathematical analysis is carried out to evaluate the delay. Delay values are analysed for variable length packets for various traffic patterns, viz. non-uniform, Poisson and ON-OFF traffic patterns for various service classes using reservation bit algorithm. The results of the class-based models are compared with the existing port-based first-fit wavelength assignment algorithm. Delay values are reduced by 29% in the class-based model than in the port-based model. Furthermore, packet transmission rate in class-based model is higher by 15.4% than port-based model.

7 illus, 13 ref

002765   Kamble R K;Panvalkar G A;Bhowmick S (NO, Central Water & Power Research Station, Khdakwasla, Pune-411 024, Email: rkkamble@gmail.com) : Electrical resistivity logging for assessing nature of foundation at kaiga nuclear power plant. J Indian Geophys Union 2012, 16(4), 161-7.

The electrical resistivity logging technique is required for assessing the nature of foundation of large power projects. The parameters determined by electrical logging serve as essential input for the design of foundation. The construction of units 3 and 4 of Kaiga Nuclear Power Plant (KNPP) was founded on granitic gneiss of lower and middle Dharwar group overlain by laterites and humus soil. Assessment on nature of the sub-surface formation was required for the design of the foundation on critical structures like turbo-generator and reactor buildings of KNPP. This paper deals with potential of electrical resistivity logging in assessing the nature of the foundation strata at KNPP and its utility of providing parameters for deciding design of the foundation of the structure.

5 illus, 4 tables, 9 ref

002764   Jindal N;Surmeet Kaur;Puneet Kumar;Arora N (CSE, Lovely Professional Univ, Phagwara, Email: nikita.jindal17@gmail.com ) : Forest sort: implementation and performance analysis. Res Rev: J embedded syst Applic 2013, 1(1), 19-23.

New technique has been introduced for sorting a large number of data set. Technique is known as Forest sort. It comprises of 3 steps-(I) a forest of binary trees has been made using hashing (2) In order traversal of each tree has been carried out concurrently (3) Merge sort has been applied to the resulting lists in (2) in a concurrent manner. A comparison has also been made with Quick Sort and in order Binary Sort. Results have proved that the performance of forest sort is far better.

1 illus, 1 table, 15 ref

002763   Izadbakhsh M A;Jahromi H M;Bajestan M S; Khosrojerdi A (Water Engineering Dep, Research Branch Islamic Azad Univ, Tehran, Iran, Email: maizadbakhsh@gmail.com) : Evaluation of hydraulic efficiency of the trapezoidal labyrinth weirs. Ecol Envir Conserv 2011, 17(2), 227-33.

Making use of the labyrinth weirs is an appropriate choice, especially for the weirs which have some inadequacies in terms of conveying the maximum probable flood. These weirs decrease considerable costs resulting from static head changes on the crest in time of strong fluctuations in the current flow of water. Understanding fully how the weirs function can reduce the weir construction costs to a considerable amount. The purpose of the present paper is to discuss the hydraulic efficiency of the labyrinth weirs by considering the discharge coefficient. Methods used in this paper are mathematical model and, flow 3D software. The models used are trapezoidal with two cycles with the width of 60 cm. Because of mixed three dimensional flows on these weirs, the flow is supposed to be turbulent. Vertical Aspect Ratio (W/P) and Head Ratio (HO/P) are chosen among all the dimensionless parameters having effects upon the labyrinth weir functions. By introducing the initial and boundary conditions and by choosing the volume of fluid model (VOF), both the position and the flow free surface came to be known. Finally, the resulting output was compared to the Tullis method known as a famous one. The result showed that firstly the vertical aspect ratio (W/P) increases in proportion to the Head Ratio (HO/P) and begins to decrease after reaching the maximum point in all the available weirs. In addition, by heightening the weirs, the discharge coefficient would increase in a specific water head. In sum, it was concluded that using a mathematical model to design such weirs can be suitable and there is no need to use designing curves.

7 illus, 6 tables, 10 ref

002762   Habibullah M;Rafiq M A;Ghosh B C (Electrical and Electronic Engineering Dep, Khulna University of Engineering and technology (KUET), Bangladesh, Email: mhueeekuet@gmail.com) : Voltage vector based torque controlled SVM controller for high performance induction motor drive. Int J Comp Applic 2011, 6(1), 15-20.

Proposes a new controller for Roly hase induction motor drive. The control principle is voltage vector based irect torque control (DTC) with .space vector modulation (SVM) technique. The torque control of DTC is implemented through the torque control loop that enhances robustness of the control system. The SVM reduces the torque ripples and improve steady state performance. On the other hand, fast dynamic speed response is obtained through maintaining the rotor flux constant as in the case qf field orientation control. A new correlated real time recurrent learning (CRTRL) algorithm bas~d recurrent neural network (RNN) is used to estimate rotor flux and torque. It is observed that the proposed control methodology provides faster speed response with reduced torque ripple than the classic DTC.

7 illus, 11 ref

002761   Habibullah M;Halder K K;Rafiq M A;Ghosh B C (Electrical and Electronic Engineering Dep, Khulna Univesity of Engineering and Technology, Bangladesh, Email: mhueeekuet@gmail.com) : A DTC based 4-switch 3-phase VSI fed high performance induction motor drive. Int J Comp Applic 2011, 6(1), 1-6.

A direct torque control methodology (DTC) for 4-switch 3-phase (4S3P) voltage source inverter (VSI) fed high performance induction motor (1M) drive is presented. In the proposed approach, instead of a conventional6-switch 3-phase inverter (6S3P) a 4S3P inverter is utilized. This reduces the cost of the inverter, the switching losses, and the complexity of the control board for generating pulse width modulated (PWM) signals. Furthermore, the proposed control approach reduces the computation for real time implementation. A proportional plus integral (PI) controller is used to process the speed error for generating reference torque to the IM. Two hysteresis controllers are used for torque and flux loops. The output of these hysteresis controllers with stator flux angle drives the switches into on or off state. Closed-loop control of the stator flux magnitude and the electromagnetic torque of the motor with Clarke's transformation are used in this study. The robustness of the drive system is tested for different perturbed operating conditions and found to work acceptably under these conditions.

6 illus, 1 table, 11 ref

002760   Habibullah M;Ghosh B C (Electrical and Electronic Engineering Dep, Khulna University of Engineering and Technology (KUET), Bangladesh, Email: mhueeekuet@gmail.com) : Quantum-inspired evolutionary algorithm based PI controller tuning for high performance induction motor drive with improved flux estimator. Int J Comp Applic 2011, 6(1), 55-60.

Quantum-Inspired Evolutionary Algorithm (QEA) is a novel algorithm for parameter optimization problems. Presents a QEA based PI controller tuning for high performance induction motor drive. An adaptive Recurrent Neural Network (RNN) with Correlated Real Time Recurrent Learning (CRTRL) algorithm is proposed to estimate rotor flux. An online tuning scheme to update the weight of RNN is presented to overcome stator and rotor resistance variation problem. This tuning scheme requires torque estimator to calculate the torque error. Space vector modulation (SVM) technique is used to produce the motor input voltage. Simulation tests have been conducted to study the dynamic performances of the drive system for both the classical PI and QEA based PI controllers.

10 illus, 15 ref

002759   Gheidari M H N (Civil Engineering Dep, Zanjan Branch Islamic Azad Univ, Zanjan Branch, Iran, Email: noorigheidari@gmail.com) : Multifractal method to estimate design probable maximum precipitation in basin of Bakhtiari dam. Ecol Envir Conserv 2011, 17(2), 177-82.

The probable maximum precipitation which is defined as the maximum precipitation at a particular location for a given duration is used as a design criterion for major dams. The assumptions of deterministic consideration and an upper limit to probable maximum precipitation have been repeatedly criticized by hydrologists. Nowadays, multifractal method which strongly contains physical bases can be used to improve the probable maximum precipitation. In this research, the universal multifractal model was used to estimate the design probable maximum precipitation for specified exceedence probability in basin of Bakhtiari Dam, southwest Iran. These results indicated that the multifractal method can be used to reasonably estimate the probable maximum precipitation.

3 illus, 1 table, 24 ref

002758   Figen A K;Piskin S (Chemical Engineering Dep, Yildiz Technical Univ, Istanbul, Turkey, Email: piskin@yildiz.edu.tr) : Mechanism for formation of NaBH₄ proposed as low-pressure process for storing hydrogen in borosilicate glass-sodium solid system: a hydrogen storage material. Bull Mater Sci 2012, 35(2), 203-09.

The mechanism for the formation of sodium borohydride (NaBH4) was investigated for its ability to store hydrogen in the borosilicate glass-sodium (BSG-Na) solid system under low hydrogen pressure. BSG, which was prepared by melting borax with silica, was used as the starting material in the BSG-Na system that would be prepared to store hydrogen. It was observed that the mechanism for storing hydrogen in the BSG-Na solid system consisted of six steps and when the BSG-Na system was heated under a pressure of 4 atm, which was created through the use of hydrogen atmosphere, the storage of hydrogen occurred at nearly 480° C for approximate duration of 200 min, with the excellent yield (97%). In addition, the hydrogen storage capacity of the NaBH₄sample was measured using the Au-PS structure, which was designed as a mini-hydrogen cell. It was determined that the minimum amount of NaBH₄ to generate the maximum volume of hydrogen gas was 12 mg/ml at 270 mV.

7 illus, 3 tables, 21 ref

002757   Eshaghi A;Eshaghi A (Faculty of Materials Science and Engineering, Maleke Ashtar Technology Univ, Isfahan, Shahinshahr, Iran, Email: eshaghi.akbar@gmail.com) : Investigation of superhydrophilic mechanism of titania nano layer thin film- silica and indium oxide dopant effect. Bull Mater Sci 2012, 35(2), 137-42.

In this paper, TiO2-SiO2-In2O3 nano layer thin films were deposited on glass substrate using sol-gel dip coating method. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and water contact angle measurements were used to evaluate chemical structure, surface composition, hydroxyl group contents and superhydrophilicity of titania films. FTIR result indicated that Si-O-Si, Si-O-Ti and Ti-O-Ti bands formed in TiO₂-SiO₂-In₂O₃ sample. According to XPS, the hydroxyl content for TiO₂, TiO₂-SiO₂ and TiO₂-SiO2-In2O3 films was calculated as 11-6,17-1 and 20-7%, respectively. The water contact angle measurements indicated that silica and indium oxide dopant improved the superhydrophilicity of titania nano film surface especially in a dark place. The enhanced superhydrophilicity can be related to the generation of surface acidity on the titania nano film surfaces. In the present state, superhydrophilicity is induced by the simultaneous presence of both Lewis and Bronsted sites.

4 illus, 1 table, 28 ref

002756   Czyzewski A;Karolczyk J;Usarek A;Prezepiorski J (Institute of Chemical and Environmental Engineering, West Pomeranian Technology Univ, ul. Pulaskiego 10, 70-322 Szczectin, Poland, Email: czyzewski_adam@zut.edu.pl) : Removal of two ionic dyes from water by MgO-loaded porous carbons prepared through one-step process from poly(ethylene terephthalate)/magnesium carbonate mixtures. Bull Mater Sci 2012, 35(2), 211-19.

Mixtures of poly(ethylene terephthalate) and magnesium carbonate at different weight ratios were heated up to 850° C in argon atmosphere. During heating, components of the initial mixtures underwent thermal decomposition yielding porous carbon materials loaded with different amounts of magnesium oxide. Structural characteristics of the prepared materials were determined from adsorption/desorption isotherms of nitrogen, measured at 77 K. For reference, portions of the products obtained were acid-washed to obtain MgO-free carbons. Pore structures of the prepared materials were strongly dependent on the quantitative compositions of starting mixtures. As a rule, specific surface areas determined for acid-washed materials were much higher than those for MgO-loaded carbons. The adsorption abilities of obtained materials towards cationic (Basic Red 18) and anionic (Reactive Red 198) dyes as model contaminants were examined. Surprisingly, in spite of relatively low specific surface areas, substantially high adsorption of the dyes on MgO-loaded carbons was observed. An influence of specific surface area and the role of magnesium oxide presence on the adsorption capacity of the acquired sorbents were studied.

7 illus, 4 tables, 34 ref

002755   Chen X;Chen Y;Tang Y (School of Materials Science and Engineering, Sichuan Univ, Chengdu-610 065, PR China, Email: ygchen60@yahoo.com.cn) : Phase relation of LaFe_11.6Si_1.4 compounds annealed at different high-temperature and the magnetic property of LaFe_11.6-xCo_xSi_1.4 compounds. Bull Mater Sci 2012, 35(2), 175-82.

LaFen_11.66Si_1.4 compounds are annealed at different high temperatures from 1323 to 1623 K. The powder X-ray diffraction patterns show that large amount of NaZn13-type phase begins to be observed in LaFen_11.6Si_1.4 compound after being annealed at 1423 K for 5 h. In the temperature range from 1423 to 1523 K, the α-Fe and LaFeSi phases rapidly decrease to form 1:13 phase. LaFeSi phase is rarely observed in the XRD pattern in the LaFen_11.6Si_1.4 compound annealed at 1523 K (5 h). With annealing temperature increasing to 1573 K and 1673 K, La₅Si₃ phase is detected, and there is a certain amount of LaFeSi phase when the annealing temperature is 1673 K. The amount of impurity phases in the LaFen_11.6Si_1.4 compound annealed by the two-stage annealing consisting of high temperature (<62>1523 K) and 1523 K is larger than that of the single stage annealing at 1523 K under the same time. According to the results of different high-temperature annealing, LaFe_11.6-xCo_xSi_1.4 (0.1 ≤ x ≤ 0.8) compounds are annealed at 1523 K (5 h). The main phase is NaZnl3-type phase, and the impurity phase is a small amount of α-Fe in LaFe_11.6-x Co_xSi_1.4 compounds. With increase in Co content from x = 0.1 to 0.8, the Curie temperature TC, goes up from 207 to 285 K. The introduction of Co element weakens the itinerant electron meta-magnetic transition, and also results in the change of magnetic transition type from first to second order at about x = 0-5. The magnetic entropy change decreases from 19.94 to 4.57 J /kg K with increasing Co concentration at a low magnetic field of 0-2 T. But the magnetic hysteresis loss around T_C reduces remarkably from 26.2 J /kg for x = 0.1 to 0 J /kg for x = 08.

9 illus, 1 table, 23 ref

002754   Chaurasia S K;Ujjwal Prakash;Misra P S; Chandra K (Metallurgical and Materials Engineering Dep, IIT Roorkee, Uttarakhand-247 667, Email: ujwalfmt@iitr.ernet.in) : Development of P/M Fe-P soft magnetic materials. Bull Mater Sci 2012, 35(2), 191-6.

Phosphorous is treated as an impurity in conventional steels owing to segregation of phosphorous and formation of brittle phosphides along the grain boundaries. It is responsible for cold and hot shortness in wrought steels. In conventional powder metallurgy, involving compaction and sintering, high phosphorous content (up to 0.7%) in Fe-based alloys exhibit attractive set of mechanical and magnetic properties. These powder-processed alloys suffer from increasing volumetric shrinkage during sintering as phosphorous is increased beyond 0.6%. Thus both cast as well as conventional powder metallurgy routes have their own limitations in dealing with iron-phosphorous alloys. Hot-powder forging was used in the present investigation for the development of high-density soft magnetic materials containing 0.3-0-8% phosphorous to overcome these difficulties. It was observed that phosphorous addition improves the final density of the resulting product. It was further observed that hot-forged iron-phosphorous alloys have excellent hot/cold workability and could be easily shaped to thin strips (0.5-1-0 mm thick) and wires (0.5-1-0 mm diameter). The powder hot-forged alloys were characterized in terms of microstructure, porosity con-tent/densification, hardness, soft magnetic properties and electrical resistivity. Magnetic properties such as coercivity 0 35-1 24 Oe, saturation magnetization 14145-17490 G and retentivity 6402-10836 G were observed. The obtained results were discussed based on the microstructures evolved.

5 illus, 3 tables, 12 ref

002753   Chandak N R (Civil Engineering Dep, G H Raisoni Institute of Engineering & Management, Jalgaon-425 002) : Response spectrum analysis of reinforced concrete buildings. J Instn Engrs : Ser A 2013, 93(2), 121-8.

In this work, a parametric study on reinforced concrete (RC) structural walls and moment resisting frames building representative of structural types using response spectrum method is carried out. Here, the design spectra recommended by Indian Standard Code [1] and two other well known codes (Uniform Building Code, Euro Code 8) have been considered for comparison. The main objective of this study is to investigate the differences caused by the use of different codes in the dynamic analysis of multistoried RC building. Three different floor plans that are symmetric (SB), monosymmetric (ME), and un symmetric (UB) with torsional irregularity are taken as sample buildings. To evaluate the seismic response of the buildings, elastic analysis was performed by using response spectrum method using the computer program SAP2000. Periods, base shears, lateral displacement and interstory drift, torque located at code defined ground type are comparatively presented. It is observed from the comparative study that the base shear using IS code is higher in all the three buildings, when compared to that of with other codes.

7 illus, 5 tables, 8 ref

002752   Bhardwaj A G;Chauhan B R S;Kalyani V L (Elecronics & Communication Engineering Dep, Government Women Engineering College, Nasirabad Road, Ajmer, Email: gwecaexam@gmail.com) : Theory & applications of discrete time signal processing. Int J latest Technol Engng Mgmt appl Sci 2012, 1(10), 216-22.

DSP is concerned with the representation of the signals by a sequence of numbers or symbols and the processing of these signals. Digital signal processing and analog signal processing are subfields of signal processing. DSP includes subfields like: audio and speech signal processing, sonar and radar signal processing, sensor array processing, spectral estimation, statistical signal processing, digital image processing, signal processing for communications, biomedical signal processing, seismic data processing, etc.

7 ref

002751   Ashwani Kumar;Nayyar P (NO, IITT College of Engineering, Pojewal, Nawanshar, Punjab, Email: tyagi.ashwani523@gmail.com ) : Digital image watermaking using discrete cosine transform. Res Rev: J embedded syst Applic 2013, 1(2), 17-22.

Digital image processing is a growing field. Digital image processing operations are mainly divided into three major categories: Image enhancement, Image compression and Image segmentation. Digital Watermarking comes under image segmentation. The present paper proposes the technique for the digital watermarking for digital multimedia. The growth in e-world which is coupled with computer network, world wide web and more over exponential advancement in computer performance. All these technologies has facilitated the distribution of data such as digital image, digital multimedia. The digital watermarking schemes have been proposed to resilience these kinds of unauthorized access of digital multimedia data. At initial stage, eneryption and control access techniques are used to copyright protection, content authentication and ownership protection. But now days, the digital watermarking techniques are used to keep digital multimedia secure. Although significant progress has been made in digital watermarking of digital multimedia, but still there are many challenges in practical world application. Watermarking is an effective way to secure the digital multimedia products by embedding the watermark into the target multimedia product to prove the copyright protection, owner's authentication on the product. In this report it will analyze all the aspects of digital watermarking technique to protect the digital multimedia content authentication and copyright and new scheme is proposed for watermarking technique.

4 illus, 1 table, 15 ref

002750   Arunkumar R;Jothiprakash V (Civil Engineering Dep, Indian Institute of Technology, Bombay, Email: arunkumar.r@iitb.ac.in) : Optimal reservoir operation for hydropower generation using non-linear programming model. J Instn Engrs : Ser A 2013, 93(2), 111-20.

Hydropower generation is one of the vital components of reservoir operation, especially for a large multi-purpose reservoir. Deriving optimal operational rules for such a large multi-purpose reservoir serving various purposes like irrigation, hydropower and flood control are complex, because of the large dimension of the problem and the complexity is more if the hydropower production is not an incidental. Thus optimizing the operations of a reservoir serving various purposes requires a systematic study. In the present study such a large multi-purpose reservoir, namely, Koyna reservoir operations are optimized for maximizing the hydropower production subject to the condition of satisfying the irrigation demands using a non-linear programming model. The hydropower production from the reservoir is analysed for three different dependable inflow conditions, representing wet, normal and dry years. For each dependable inflow conditions, various scenarios have been analyzed based on the constraints on the releases and the results are compared. The annual power production, combined monthly power production from all the powerhouses, end of month storage levels, evaporation losses and surplus are discussed. From different scenarios, it is observed that more hydropower can be generated for various dependable inflow conditions, if the restrictions on releases are slightly relaxed. The study shows that Koyna dam is having potential to generate more hydropower.

11 illus, 2 tables, 35 ref

002749   Ansari J A;Kamakshi;Singh A;Mishra A;Yadav N P (Electronics & Communication Dep, University of Allahabad, Allahabad-211 002, Email: kamakshi_teri_el@yahoo.co.in) : Analysis of L-strip fed rectangular patch antenna with U_slot. Int J Comp Applic 2011, 6(1), 27-31.

A wide-band L-strip fed U_Slot loaded rectangular microstrip patch antenna is proposed and investigated both theoretically and simulated. Antenna shows an impedance bandwidth of 42.8% with operational frequency band ranging from 2.9 GHz to 4.55GHz and good agreement is obtained between theoretically and simulated results. The effects of the geometric parameters of the L-strip like length and Width of the strip are investigated. It is easy to adjust the higher and lower Resonance frequency band by changing the dimensions of L-strip. It is found that the resonance frequency also depends on the slot dimenSions. The theoretical results are compared with IE3D simulation results which are in good agreement. It is found that the antenna attains 43.5% (Theoretically) impedance bandwidth and 42.8% (Simulated) for optimized antenna design.

9 illus, 1 table, 18 ref

002748   Anburaj R;Udayaprakash J;Ezilarasan C (Mechanical Engineering Dep, Indian Institute of Technology, Madras, Email: ranburaj@iitm.ac.in) : Investigation effectc of the machining parameters on the material removal rate in the wedm of AISI D3 tool steel. Mfg Technol Today 2012, 11(6), 5-14.

Tool steel, AISI D3, is widely used in tool and die making industries due to its high strength and toughness. In this article, an attempt has been made to investigate the effect of the machining parameters, such as pulse on time (T_on), pulse off time (T_off), gap voltage (v) and wire tension (WT) on the material removal rate (MRR) in the WEDM of AISI D3 tool steel, to improve the machining rate in manufacturing industries. The experiments were conducted using Taguchi's experimental design. An orthogonal array L₁₆ was used to conduct the experiments. The effect of the machining parameters on the material removal rate is evaluated. Experimental data are analyzed with the analysis of variance (ANOVA). A second order response surface model has been established between the machining parameters and the MRR, using response surface methodology. The experimental results indicate that the pulse off time (T_off) significantly affects the MRR, followed by pulse on time (T_on) and gap voltage (v). The predicted values are very close to the experimental values.

8 illus, 4 tables, 18 ref

002747   Ali A;Agarwal V;Birla D K (NO, , ) : Modeling simulation and performance analysis of D-STATCOM at the time of voltage sag. Int J latest Technol Engng Mgmt appl Sci 2012, 1(10), 163-7.

The project focuses on the behavior of power system. Author found out how the quality of power corrects by using facts devices. The power system getting overloaded due to increasing load demand, steep growth of national economics and restructuring of power system. This naturally demands more optimal and profitable operation of the power system with respect to generation, transmission, and distribution. To achieve both operational reliability and financial profitability, it has become necessary to utilize and control the existing transmission system more efficiently. The development of the modern power system has led to an increasing complexity in the study of power systems, and also presents new challenges to power system stability, and in particular, to the aspects of transient stability and small-signal stability. Transient stability control plays a significant role in ensuring the stable operation of power systems in the event of large disturbances and faults, and is thus a significant area of research.

5 illus, 12 ref

002746   Ahmed M G;Khan N Z (Electronics & Telecommunication Engineering Dep, Dr. N.P. Hirani Institute of Polytechnique, Pusad, Affiliated to MSBTE, Mumbai, Maharashtra) : Design of microcontroller based automated power saving system for classrooms. Res Rev: J embedded syst Applic 2013, 1(2), 9-16.

Present scenario of energy crisis not only demands to increase generation of energy but also to utilize it as per legitimate requirement to conserve at public places like educational institutes, where the users are more and no one cares to switch OFF appliances when not required. The aim of this project is to design cost effective automated system which can he easily incorporated in academic institution especially in the class rooms to conserve the energy. Lights and fans switched ON and OFF as per requirement for number of students entered in the class room through person counting subsystem. The implementation is made simpler by using sensor to detect person and compact circuitry built around 8051 microcontroller programs. Through this system, the author wishes to inculcate discipline in the students by giving no option but to occupy the front row first and so on and back benchers to come in front and then only have the comfort of light and fan and at the same time want to help academic institutes to save money on their power bills and. contribute in reducingthe emission of green house gases in environment.

3 illus, 2 tables, 7 ref

002745   Ahamd F;Jamil M;Jeon Y J;Woo L J;Jung J E; Jang J E (Chemistry Dep, Konkuk Univ, Seoul-143 701, Korea, Email: yjjeon@konkuk.ac.kr) : Investigation of nonionic diazo dye-doped polymer dispersed liquid crystal film. Bull Mater Sci 2012, 35(2), 221-31.

Sudan black B (SBB) was used to investigate as the nonionic diazo dye-doped in polymer dispersed liquid crystal (PDLC) display, by polymerization-induced phase separation (PIPS) method. The maximum absorbance, contrast ratio, dichroic ratio and the order parameter of nonionic diazo dye in nemetic host (TL203) were investigated using UV-Vis polarized spectroscopy. The orientation of the dye molecules was controlled by electric field, which enabled the contrast ratio of the dye to be obtained by electrically switching. The change occurring on droplet morphologies and electro-optical properties of PDLC film with the change in contents of Sudan black dye and liquid crystals (LC) contents was investigated. We found an increase in LC droplet sizes with the increase of diazo dye and LC contents. Moreover the addition of small amount of nonionic diazo dye reduced the threshold voltage (V_th), increased off-state transmittance, enhanced the contrast ratio and decreased the response time of dye-doped PDLC. Additionally the change in transition temperature of LC and changes in LC droplet morphologies with the addition of dye were also observed. Such changes were observed with the images taken by polarized optical microscope (POM). The detail discussions on such behaviours were also made.

10 illus, 2 tables, 39 ref

001753   Zamiri R;Azmi B Z;Ahangar H A;Zamiri G;Husin M S;Wahab Z A (Physics Dep, Faculty of Science, Putra Malaysia Univ, 43400 UPM, Serdang, Selangor, Malaysia, Email: azmizak@gmail.com) : Preparation and characterization of silver nanoparticles in natural polymers using laser ablation. Bull Mater Sci 2012, 35(5), 727-31.

In this paper we have done a comparative study on efficiency of natural polymers for stabilizing silver nanoparticles (Ag-NPs) prepared by laser ablation technique. The selected polymers are starch (St), gelatin (Gt) and chitosan (Ct). The fabrication process was carried out through ablation of a pure Ag plate by nanosecond Q-switched Nd-Yg pulsed laser (λ = 532 nm, 360 mJ/pulse). The stability of the samples was studied by measuring UV-visible absorption spectra of the samples one month after preparation. The result showed that the formation efficiency of NPs in St were highest and also the prepared NPs in St solution were more stable than other polymers during one month storage.

4 illus, 17 ref

001752   Zakeri M;Ahmadi M (Ceramic Dep, Materials and Energy Research Centre, P.O. Box 31787/316, Tehran, Iran, Email: M_zakeri@merc.ac.ir) : Effect of starting composition on formation of MoSi₂-SiC nanocomposite powder via ball milling. Bull Mater Sci 2012, 35(4), 533-8.

MoSi₂-SiC nanocomposite powders were successfully synthesized by ball milling Mo, Si and graphite elemental powders. Effects of milling time and annealing temperature were also investigated. The composite formation and phase transformation were monitored by X-ray diffraction. The microstructure of milled powders was studied by SEM, TEM and XRD peak profile analysis. Formation of this composite was completed after 10 and 20 h of milling for 25%SiC and 50%SiC, respectively. High temperature polymorph (HTP) of MoSi2 was obtained at the end of milling (20 h). On the other hand, annealing led to transformation of HTP to low temperature polymorph (LTP) of MoSi2. Mo₅Si₃ was formed during annealing as a product of a reaction between MoSi₂ and excess graphite. Mean grain size <60>50 nm was obtained for 20 h milled sample on the basis of peak profile analysis and TEM images.

7 illus, 2 tables, 20 ref

001751   Yang Y J (School of Chemistry and Chemical Engineering, Xuchang Univ, Xuchang, China, Email: yangyujun@yahoo.com) : Morphological and compositional engineering of Ni/carbon nanotube composite film via a novel cyclic voltammetric route. Bull Mater Sci 2012, 35(4), 513-7.

Ni/multi-walled carbon nanotubes (MWCNTs) composite films were deposited on the glassy carbon electrode (GCE) by a Ni plating bath containing homogeneously dispersed MWCNTs using polyvinylpyrrolidone (PVP) as dispersion additive. Incorporation of MWCNTs into Ni matrix was greatly enhanced by the application of cyclic voltammetric (CV) deposition technique. The structure and nature of the Ni/MWCNT were characterized by field emission scanning electron microscope (FE-SEM) and X-ray diffraction (XRD). The results show that the content of MWCNT and the morphology of the deposited Ni/MWCNT composite film can be controlled by selecting the appropriate electroplating conditions. Further study indicates that the obtained Ni/MWCNT showed excellent electro-catalytic activity for the oxidation of ethanol in alkaline solution.

7 illus, 22 ref

001750   Yang C (Materials Science and Engineering Dep, Fujian Technology Univ, Fuzhou-350 108, China, Email: lambmeo@163.com) : Enhanced physicochemical properties of collagen by using EDC/NHS-crosslinking. Bull Mater Sci 2012, 35(5), 913-8.

Collagen-based scaffolds are appealing products for the repair of cartilage defects using tissue engineering strategies. The present study investigated the collagen scaffolds with and without l-ethyl-3-(3-dimethyl amino-propyl) carbodiimide (ED/N-hydroxysuccinimide (NHS)-crosslinking. Crosslinking density, matrix morphology, swelling ratio shrinkage temperature and resistance against collagenase digestion were determined to evaluate the physicochemical properties of the collagen matrices with and without crosslinking. The results conformed that the porous structure of collagen was largely preserved and adjusted by crosslinking treatment. Furthermore, crosslinked collagen samples showed significantly reduced swelling ratio and increased resistance against thermal treatment and enzymatic degradation compared to non-crosslinked samples. An in vitro evaluation of MC3T3-E1 cells seeded onto the crosslinked and non-crosslinked collagen matrix indicated that crosslinked collagen was nontoxic and improved cell proliferation. Through this work, it was shown that an osteoconductive collagen matrix with optimized properties used as bioactive and bioresorbable scaffolds in bone tissue engineering could be fabricated through the EDC/NHS-crosslinking method.

7 illus, 1 table, 16 ref

001749   Xu Q;Gong Y;Fang Y;Jiang G;Wang Y;Sun X;Wang R (Materials Engineering Dep, College of Materials and Textile Zhejiang Sci-Tech Univ, Hangzhou-310 018, Email: polymer_jiang@hotmail.com ) : Straightforward synthesis of hyperbranched polymer/graphene nanocomposites from graphite oxide via in situ grafting from approach. Bull Mater Sci 2012, 35(5), 795-800.

The grafting of graphite oxide (GO) with cyclic ether monomers, directly affords grafting with hyper-branched polymers. The resulting nanocomposites show good solubility in the solvents of polymers, exfoliation of graphene in the polymer matrix and excellent mechanical properties and robustness under bending.

4 illus, 33 ref