017628   Ozolcer I H;Komurcu M I (Civil Engineering Dep, Zonguldak Karaelmas University, 67100 Zonguldak, Turkey, Email: ozolcer@hotmail.com) : Effects of straight groin parameters on amount of accretion. Indian J Mar Sci 2007, 36(3), 173-82.

Various types of structures are used in shore protection and littoral sediment trapping. Groins are one of these structures. The main hydraulic function of the groin is to control the long shore current and littoral sediment transport. The effects of various groin parameters (length and spacing) and wave parameters (wave height, wave period and wave angle) on the accretion of the area protected by straight groin were studied in a physical model. The model studies were performed using regular waves in a basin. A numerical model which depends primarily on a CERC model is employed to examine the effects of some of the above parameters. Good agreement was found in the results of physical and numerical models. The results of a numerical model are compared with field data that were obtained by deep sounding measurements at Carsibasi coasts, Trabzon Province, Turkey. The important outcome from this study may be employed in designing of straight groins.

017627   Oestges C (NO, Microwave Laboratory, 3 place du Levant, Universit‚ catholique de Louv, , Email: oestges@emic.ucl.ac.be) : Propagation channel, capacity and error probability for dual-polarized wireless transmissions. Indian J Radio Space Phys 2007, 36(5), 411-17.

Use of dual-polarized arrays in multiple-input multiple-output (MIMO) systems is addressed in this paper. A new and simple analytical model of dual-polarized Rayleigh and Ricean fading channels is taken, which relies on a limited number of physical parameters, such as the spatial correlations, the co-polar gain imbalance and the cross-polar discrimination. Then, the multiplexing advantage of dual-polarized transmissions is investigated through the evaluation of the ergodic mutual information. Finally, the performance of two space-time coding schemes (Alamouti O-STBC and un-coded Spatial Multiplexing) is evaluated via a detailed analysis of the pair-wise error probability (PEP).

017626   Kuniyal J C;Rao P S P;Momin G A;Safai P D; Tiwari S;Ali K (NO, G B Pant Institute of Himalayan Environment and Development, Himachal, Mohal-Kullu-175 126, Email: kuniyaljc@yahoo.com) : Trace gases behaviour in sensitive areas of the northwestern Himalaya-a case study of Kullu-Manali tourist complex, India. Indian J Radio Space Phys 2007, 36(3), 197-203.

Surface concentration of the three important trace gases, ozone (O₃), nitrogen dioxide (NO₂) and sulphur dioxide (SO₂) were measured at three different tourist locations, namely Kullu, Manali and Kothi in the northwestern Himalayan region, which are located at 1220 m, 2050 m and 2530 m above the mean sea level mainly to asses the anthropogenic impact. The surface O₃ was monitored for four years during the period 1998 - 2002 and 2004 at the time of peak tourist season (May-June), and SO₂ and NO₂ were measured during the entire period in 2003. The peak O₃ concentrations reached close to 50 ppb level, while the annual mean concentrations of O₃, SO₂ and NO₂ remained within the United States Environmental Protection Agency's (USEPA's) National Ambient Air Quality Standards (NAAQS). The peak hourly average values of O₃ was 44 ppb at Manali and 32 ppb at Kothi during evening (1700 hrs IST), while that at Mohal (near Kullu) was 32 ppb in the afternoon (1500 hrs IST) period. The seasonally average value of maximum concentration of NO₂ was 3.8±0.6 μg m^-3 at Kothi and 7.6±1.0 μg m^-3 at Mohal in autumn (October-November), while that of SO₂ was 21.4±1.8 μg m^-3 at Kothi and 18.8±1.3 μg m^-3 at Mohal during the monsoon (July-September) and summer (April-June) periods, respectively. Vehicular emissions and biomass burning for heating and cooking during the winter period (especially when power failure is common) as well as during forest fires could be the major contributors for increased emissions of these trace gases. However, the influence of long-range transport may also be important.

017625   Jhunjhunwala A (Electrical Engineering Dep, Indian Institute of Technology, Chennai-600 036, Email: ashok@tenet.res.in ) : Next generation wireless for rural areas. Indian J Radio Space Phys 2007, 36(3), 165-7.

Following a spectacular growth of telecommunication in India, the country is focusing on the technology to provide broadband connections to its rural areas. Broadband wireless technologies are emerging to enable this to happen. Four such technological efforts are on the horizon. The paper looks at the four initiatives and what they could deliver to Indian rural areas in the next few years.

017624   Iyer S (KR School of Information Technology, Indian Institute of Technology, POWAI, Mumbai-400 076, ) : Rural radio communications: Services and applications. Indian J Radio Space Phys 2007, 36(3), 192-3.

The internet has enormous power to transform rural communities. Internet based services can mitigate the gap between urban and rural areas in terms of access to various services, such as health-care, domain consultancy and education. It can also provide new avenues of income generation to rural areas. This paper gives an overview of some existing internet based services and applications for rural India and presents a case study of one application in Education.

017623   Batllori E;Febles J L (Human Ecology Dep, CINVESTAV, Research and Advanced Studies Center of I.P.N., Km 6 Antigua Carretera a Progreso, A.P. 73, Cordemex, Merida, 97310, Yucatan, Mexico, Email: batllori@mda.cinvestav.mx) : Changes in the hydrological characteristics of Chabihau coastal wetlands, Yucatan, Mexico, associated with hurricane Isidore impact. Indian J Mar Sci 2007, 36(3), 183-92.

Describes changes in the hydrologic behavior of Chabihau coastal lagoon, Yucatan, Mexico, associated with the impact of Hurricane Isidore (2002) and the construction of hydraulic infrastructure in coastal highways, through the spatiotemporal analysis of the water physicochemical variables, from the 1999 flood season to the 2005 dry season. The coastal wetlands were subdivided into three areas: San Crisanto swamp in the west, Chabihau lagoon in the center, and Santa Clara swamp in the east. After the hurricane impact and construction of bridges in the coastal dune, stronger tide's ebb into the Chabihau lagoon was recorded, changing it from a hyperhaline system to an euryhaline one. On the other hand, changes to hyperhaline conditions were observed in Santa Clara swamp during dry and flood seasons. After the hurricane, negative redox values were recorded throughout the entire Chabihau wetlands, in addition to a reduction in dissolved oxygen and pH, during both dry and flood seasons. This situation determined dominance of reductive processes in the three areas, with low temporal variability. If the salinization process continues in the Santa Clara swamp, changes may occur in the structure and composition of the mangrove forest.

017622   Bandyopadhyay L K;Mishra P K;Kumar S; Selvendran D;Chaulya S K (NO, Central Institute of Mining & Fuel Research, Dhanbad 826 001, Email: laxmikb@yahoo.com) : Studies on radio frequency propagation characteristics for underground coalmine communications. Indian J Radio Space Phys 2007, 36(5), 418-22.

Basic understanding of the behaviour of electromagnetic wave propagation through strata is the fundamental requirement to design a suitable wireless communication system for underground mines. Background information on radio propagation and its limitations, in a particular confined space can be known only after the measurement. Both electromagnetic propagation studies and modelling of propagation coverage, ultimately help in selecting the best suitable frequency and designing appropriate wireless communication system for underground mine. Discusses different aspects for propagation modelling and the experiment conducted in the laboratory to understand the propagation characteristics through coal. It is found that 6 MHz frequency is the best suitable frequency for propagation of electromagnetic wave through coal.

017621   Anil Kumar;Sarkar S (Radio and Atmospheric Sciences Div, National Physical Laboratory, New Delhi-110012, Email: sksarkar@mail.nplindia.ernet.in) : Cloud attenuation and cloud noise temperature over some Indian eastern stations for satellite communication. Indian J Radio Space Phys 2007, 36(5), 375-8.

Cloud characteristics in relation to radio wave propagation over some selected locations in different geographical region in eastern India have been presented. It is seen that low cloud occurrence over Patna, Bhubaneswar and Ranchi is quite significant. The performance of radio systems deteriorates due to cloud attenuation as well as due to cloud noise temperature. Based on the cloud attenuation results, the total atmospheric noise temperature including the noise contribution from cloud for different months during different times for different cloud thicknesses at 10 GHz, 18 GHz, 32 GHz, 44 GHz and 70 GHz has been determined for the aforesaid stations. The results, presented are useful to design future earth- space communication links over these aforesaid locations in India.

016578   Yogesh P;Kannan A (Computer Sci Engng Dep, Coll of Engng, Anna Univ, Chennai, Email: yogesh@annauniv.edu) : Modified combined-metrics culster based service oriented architecture with improved quality of service for as hoc networks. Int J mathl Sci 2007, 6(3-4), 305 17.

Both wired and wireless networks are based on the best-effort model of the IP networks. IP networks are not able to provide any guarantee about the offered services to the users. In wireless scenario, providing Quality of Service (QoS) in Ad-Hoc networks is more difficult than in networks with access points because of the lack of infrastructure. difficulty in the prediction of the location of nodes, power requirements in the nodes and the necessity of every node functioning like a router. Existing routing protocols suffer from large amount of overhead involved especially in high-density high-mobility scenario. Overheads involved in Route discovery and Route maintenance of both reactive and proactive routing protocols is very high. Propose a method to enhance the performance of reactive routing protocol and thereby to improve the Quality of Service provided by the Mobile Ad hoc Network (MANET). In this work, empower reactive routing protocol with a clustering layer to reduce the overhead involved. We implement the cluster heads with a specific service. Compare the performance of reactive routing protocol without clustering and the performance of reactive protocol with clustering. We create the hierarchy in MANET using Modified Weighted Clustering Algorithm (MWCA). Modified protocol along with clustering improves the QoS in terms of packet delivery ratio, end-to-end delay and throughput.

2 illus, 2 tables, 14 ref

016577   Suresh Babu A V;Rao V V;Muralikrishna I V (Space Dep, Water Resoures Div, National Remote Sensing Agency, Hyderabad-500 037, Email: sureshbabu_av@nrsa.gov.in) : Satellite remote sensing derived spatial water utilisation index (Wui) for benchmarking of irrigation systems. J Indian Soc Remote Sens 2007, 35(1), 81-91.

Water Utilisation Index (WUI) defined as area irrigated per unit volume is a measure of water delivery performance and constitutes one of the important spatial performance indicators of an irrigation system. WUI also forms basis for evaluating the adequacy of seasonal irrigation supplies in an irrigation system (inverse of WUI is delta, i.e. depth of water supplied to a given irrigation unit). In the present study WUI and adequacy indicators were used in benchmarking the performance of Nagarjunasagar Left Canal Command (NSLC) in Andhra Pradesh. Optimised temporal satellite data of rabi season during the years 1990-91 and 1998-99 was used in deriving irrigated crop areas adopting hierarchical classification approach. Paddy is the predominant crop grown and cotton, chillies, sugarcane etc. are the other crops grown in the study area. Equivalent wet area (paddy crop area) was estimated using the operationally used project specific conversion factors. WUI was estimated at disaggregated level viz., distributary, irrigation block, irrigation zone level using the canal discharge data. At project level, WUI estimated to be 65 ha/MCM and 92 ha/MCM during rabi season of 1990-91 and 1998-99 years respectively. A comparison of total irrigated area and discharges corresponding to both the years indicate that irrigation service is extensive and sub optimal during 1998-99 and it is intensive and optimal in 1990-91. It was also observed that WUI is lesser in blocks of with higher Culturable Command Area (CCA) compared to the blocks of lower CCA. All the disaggregated units were ranked into various groups of different levels of water distribution performance. The study demonstrates the utility of WUI as spatial performance indicator and thus useful for benchmarking studies of irrigation command areas. The WUI together with satellite data derived spatial irrigation intensity, crop productivity constitutes important benchmarking indices in irrigation command areas.

5 illus, 1 table, 20 ref

016576   Singh O P;Satish Chand (Mechanical & Production Engg Dep, Beant Coll of Engg & Tech, Gurdaspur-143 521, Email: ompal@lycos.ecom) : Ranking of decision making units: a review and development of new model using data envelopment analysis approach. Opsearch 2007, 44(3), 185-201.

A key limitation of Data Envelopment Analysis (DEA) models are their inability to rank the decision making units (DMUs) particularly efficient ones. In this paper a systematic review of literature concerned to ranking of DMUs is presented. Thereafter a new model has been developed by extending the DEA model using merger methodology. According to this methodology in a set of n DMUs, one DMU is merged in another DMU simply by adding their inputs and outputs linearly while keeping the inputs and outputs of unmerged DMUs unaltered. These DMUs are then reanalyzed to get the relative efficiency of newborn DMU (achieved by merging two DMUs) and revised efficiencies of unmerged DM Us. Thereafter the same merging process is iterated for all possible combinations of mergers in a systematic manner. By doing this process author obtained ¹¹C₂ total number of efficiencies for each DMU. Qut of this set of results the frequency of occurrences of 100% efficiency for each DMU is counted. The DMU which has the maximum frequency of such occurrence has been assigned the top rank and others are put under lower rankings in order of occurrence of frequencies. In this approach maximum numbers of DMUs are assigned the ranking except few DMUs where there is a tie in the frequency. The ranking of such DMUs is decided on the basis of frequency of occurrences of higher efficiency scores.

7 ref

016575   Shirahatti M S;Itnal C J;Mallikarjunappa Gouda D S (Agric Engng Dep, Regional Agric Res Station, Bijapur-586 101) : Impact of differential methods of irrigation on yield levels of cotton in red soils. Karnataka J agric Sci 2007, 20(1), 96-8.

Field experiment was conducted at Agricultural Research Station, Hanumanmatti for comparing the drip and furrow irrigation methods on the hybrid cotton yields in the red sandy loam soil of northern Karnataka. The results of the experiment indicated that by applying same quantity and 50 per cent of water as of surface irrigation (control), the yield was increased by 28 and 10 per cent respectively. When the water applied in the drip irrigation was 25 per cent of the control, the yield was reduced by just 2.5 per cent, but in this case highest water use efficiency was observed. The soil moisture distribution along the vertical direction increased and laterally it was decreased.

2 tables, 6 ref

016574   Sarma J N;Borah D;Goswami U (Applied Geology Dep, Dibrugarh Univ, Dibrugarh-786 004, Email: jnsdu@yahoo.com) : Change of river channel and bank erosion of the burhi dihing river (Assam) assessed using remote sensing data and GIS. J Indian Soc Remote Sens 2007, 35(1), 93-100.

The Burhi Dihing river flows in a meandering course for about 220 km through alluvial plains of Assam including a short rocky and hilly tract in between. Sequential changes in the position of banklines of the river due to consistent bank erosion have been studied from Survey of India topographic maps of 1934 and 1972, and digital satellite data of 2001 and 2004 using GIS. Two broad kinds of changes have been observed, e.g. alteration of direction of flow due to neck cut-off and progressive gradual change of the meander bends that accounts for translational. lateral, rotational, exiensional and other types of movement of the meander bends. Study of bankline shift due to the bank erosion has been carried out for the periods 1934-1972. 1972-2001. 2001-2004 and 1934-2004 at 13 segments spaced at 5' longitude interval (average 15 km) as the river course trends nearly east to west. The amounts of the bank area lost due to erosion and gained due to sediment deposition are estimated separately. The total area eroded in both banks during 1934-1972 was more (26.796 km²) as compared to sediment deposition (19.273 km²). whereas total sediment deposition was more (34.61 km²) during 1972-2001 as compared to erosion (23.152 km²). Erosion was again more in 2001-2004 (7.568 km²) as compared to sediment deposition (2.493 km²). During the entire period (1934-2004) of study the overall erosion on the both banks was 31.169 km² and overall sediment deposition was 30,101 km². The highest annual rates of bank erosion as well as bank building of the river are 21055.47 m₂km in 2001-2004 and 9665 81 m²/km in 1972-2001. respectively Similarly the highest average annual rates of erosion as well as sediment deposition in both banks are observed during 2001-2004 and 1972-2001. respectively. The hard rocks of the hilly tract situated in between result in development of entrenched meandering and this tract has suffered minimum bank erosion.

4 illus, 1 table, 12 ref

016573   Sambasiva Rao V;Pal S (Communication Systems Group, ISRO Satellite Centre, Airport Road, Bangalore-560 017, Email: vssrao@gmail.com) : Insight into the factors affecting high bit rate data transmission from satellite to ground stations. J Coop Univ Res Ind Enterpr 2008, 1(2), 33-40.

Transmission of higher and higher bit rate data from remote sensing satellites is becoming essential due to the increasing demand for sub meter resolution imageries. Various techniques to conserve spectrum and utilize onboard power efficiently are explored for transmitting very high bit rate data from satellites. Quite a few factors are limiting the utilization of spectrum and onboard power for transmission of higher bit rate data from remote sensing satellites. Discusses the issues related to the transmission of increasing high bit rate data from satellites.

6 illus, 1 table, 7 ref

016572   Ravi Kumar Y;Rao C S P;Janardhan Reddy T A (Mechanical Engg Dep, National Institute of Technology, Warangal, Email: raviykumar@yahoo.com) : Design of experimental approach to determine the effect of process parameters on strength of SLS parts. Mfg Technol Today 2007, 6(2), 20-4.

Rapid prototyping (RP) technique has come to stay as one of the promising techniques for cutting down product development time by way of realizing a touch and feel prototype or a prototype, component that can be directly used in assemblies, product testing, or tooling for short or medium run production. Selective Laser Sintering (SLS) is a leading process for developing rapid prototype objects by selectively fusing layers of powder according to numerically defined cross sectional geometry. The parts produced by SLS have lower strength than the parts produced by conventional techniques like injection moulding. The part strength is affected by the various process parameters used in SLS process. Three parameters, namely, laser power, scan spacing and part orientation were identified and the range of the parameters for the present investigation. In the present work an attempt has been made to study the affect of these parameters on part strength. Taguchi method of experimental design is used to plan the experiments. The experiments were conducted by using DuraForm PA (polyamide) powder on a DTM Sinter station 2500^plus SLS rapid prototyping machine. The experimental results are summarized by using the analysis of variance (ANOVA) method where significant main factors and their interactions are identified. The relationship plots between the part strength and process parameters are obtained by using MATLAB 6.0 software. This paper gives the results of the study and the conclusions drawn from it.

4 illus, 10 tables, 7 ref

016571   Ramamurti V;Jayadurga G (NO, , 2 Fourth Main Road, Kasturibai, Chennai-600 020) : Efficient algorithm for solving cyclic symmetric problems. Proc Indian Natn Sci Acad 2007, 73(4), 209-19.

Egant approach to solve all the problems connected with cyclic symmetric structures is presents. The presentation includes static, Eigen value and dynamic analyses. All the three types of elements viz beam, shell and brick are used. All the associated source codes have been developed. Two typical applications in mechanical engineering viz wheels with spokes and gear teeth are used as examples to establish the efficacy of this approach. Emphasis has been on the memory needed to store the information and time needed to solve the problems.

22 illus, 3 tables, 18 ref

016570   Rajesh Kumar;Singh R (Mechanical Engg Dep, R.I.E.I.T., Railmajra, Distt Nawanshahr-144 553, Email: rupindersingh78@yahoocom) : New role for micro-alloyed steels: adding economic value. Mfg Technol Today 2007, 6(3), 12-16.

Micro-alloyed (MA) steels have matured during the past 40 years into an important class of high strength structural materials. Their cost-effectiveness has been enhanced by the growth of steel making electric-are-furnace (EAF) and the thin-slab-casting process. A recent project involving an ultra-light-steel auto body (ULSAB) concluded that high-strength-steels are the materials of choice for the automotive industry. This study showed that replacing cheaper carbon steels with high-strength steels allowed automakers to reduce the weight of an auto body at the same or at potentially lower costs. The same economic principles can be applied to other applications. The strengthening effects of vanadium make microalloyed steels particularly suited for highstrength-steel applications. By effectively combining grain refinement and precipitation hardening, vanadium maximises the strengthening process and is compatible with current steel-processing technology. To dramatise the cost effectiveness of these high-strength-steels in potentially new applications, a series of demonstration projects are needed involving the co-operation of steel producers, fabricators, and users. In many applications, the decision to replace plain-carbon steel with higher strength vanadium-bearing microalloyed steel can be shown to improve the profitability of both the steelmaker and the steel user.

6 illus, 17 ref

016569   Rajesh Kumar;Rupinder Singh (Mechanical Engineering Dep, R.I.E.I.T., Railmajra, Distt. Nawanshahr-144 553, Email: rupindersingh78@yahoo.com) : Effects of process variables on HAZ in submerged arc welds of structural steel pipes. Mfg Technol Today 2007, 6(4), 23-30.

In submerged arc welding (SAW), selection of appropriate values of process variables is essential in order to control heat-affected zone (HAl) dimensions and to get the required bead size and quality. Also, conditions must be selected that will ensure a predictable and reproducible weld bead, which is critical for obtaining high quality. In this investigation, mathematical models were delleloped to study the effects of process variables and heat input on various metallurgical aspects, namely, the widths of the HAl, weld interface, grain growth and grain refinement regions of the HAl. The color metallographic technique and response surface methodology were used for analysis. Direct and interaction effects of the process variables and heat input on the characteristics of the HAl were presented in graphical forms. The study revealed that heat input and wire feed rate have a positive effect, but welding speed has a negative effect on all HAl characteristics; secondly width of grain growth and grain refinement zones increased and weld interface decreased with an increase in arc voltage; and width of HAl is maximum (about 2.2 mm) when wire-feed rate and welding speed are at their minimum limits.

14 illus, 5 tables, 15 ref

016568   Prabu T;Rudramoorthy R (School of Energy, PSG Coll of Technol, Coimbatore, Email: prabuvel@yahoo.com) : Optimization of centrifugal pump impeller. Int J mathl Sci 2007, 6(3-4), 497-505.

Power to drive the pump is always greater than the output power of the fluid being pumped. The power loss inside the pump is mainly due to hydraulic, volumetric and mechanical losses and depends to a larger extent on the design of the impeller. The main objective of this work is to optimise the design of the impeller of a centrifugal pump using the inverse design approach. The impeller of a commercial centrifugal pump was analysed using a Computational Fluid Dynamics (CFD) package and the pressure distribution at various locations on the blade curvature were determined. Pressures at different locations are expressed in terms of the design variable. Development of an ideal pressure distribution, which when obtained on the impeller blade curvature will ensure the maximum efficiency of the pump. This target pressure was obtained by using the steady flow energy equation along the impeller blade curvature, with the assumption of inviscid fluid without eddy formation and flow separation. The actual pressure distribution in the impeller of the pump and the target pressure distributions are compared to set an objective function, which when minimized gives the optimum for the design.

5 illus, 3 tables, 7 ref

016567   Noorul Haq A;Tamizharasan T (Production Engg Dep, National Institute of Technology, Thiruchirappalli-620 015, Email: anhaq@nitt.edu) : Investigation of the effect of workpiece hardness on flank wear, energy consumption and surface roughness in dry turning. Mfg Technol Today 2007, 6(4), 9-14.

The effect of workpiece hardness on flank wear of cutting tool, electrical energy consumption and roughness of machined surface in dry turning operation at two different cutting speeds are experimentally investigated. The dry turning experiments are conducted with coated carbide inserts. The workpieces are selected with ten different hardness values ranging from 10 to 55HRC. The two levels of cutting speed selected are 100m/min. and 50m/min. and the other parameters such as feed rate and depth of cut are maintained constant at O.3mm/rev. and O.5mm respectively Each experiment is conducted for an experimentally determined duration of 31 minutes and at the end of each experiment, the flank wear, electrical energy consumption and arithmetic average surface roughness of machined surface are measured and recorded. The flank wear is significantly affected by the hardness of workpiece and cutting speed. This analysis provides guidelines on tool and workpiece material selection in finish dry turning operations for minimizing tool wear and energy consumption by maintaining the surface roughness value at the desired level.

13 illus, 1 table, 18 ref

016566   Natarajan A;Venkata Rao R (Mechanical Engng Dep, Sri Krishna Coll of Engng and Technol, Coimbatore-641 008) : Design of cellular manufacturing systems using a genetic algorithm method. Opsearch 2007, 44(2), 137-46.

Cellular Manufacturing (CM) is an important application of group technology in which sets or families of parts are produced in manufacturing cells or a group of various machines, which are physically close together and can process a family of parts. The identification of part families and machine groups in the design of cellular manufacturing systems is commonly referred to as cell design or cell formation. The cells are formed to capture the inherent advantages of group technology such as reduced setup times, reduced in-process inventories, improved product quality, shorter lead time, reduced tool requirements, improved productivity etc. This paper presents the design of cellular manufacturing systems using a genetic algorithm method considering maximization of flexibility and efficiency. An example is included to illustrate the approach.

1 illus, 3 tables, 12 ref

016565   Nalawade S M;Gajakos A V;More L D (Agricultural Engineering Dep, College of Agricultural Engineering and Technology, Dapoli, Ratnagiri, Maharashtra) : Performance evaluation of tie-ridger. Agric Update 2008, 3(1-2), 66-8.

Research experiment on testing of tractor-operated tie-ridger for the evaluation of its performance was carried out at M. P. K. V. Rahuri (M. S.). The tractor-operated tie-ridger was tested in laboratory as well as in the field. In laboratory testing checking for the material of construction and the adjustments was done. Tie-ridger was operated in field with different field conditions to collect data viz., working width, effective field capacity and field efficiency which found to be 2.94 m, 0.545 ha/hr and 54.6% respectively at corresponding average forward speed of 3.5 km/hr. The basin formation requires well-pulverized soil with leveled field. In spite of some limitations and drawbacks, it is observed that tie-ridger can be used for basin formation (6m x 3m size) with some modifications.

2 tables, 5 ref

016564   Mohamed Ameen A;Sivakumar K (NO, J.J. College of Engineering and Technology, , Email: engineer_ameen@yahoo.co.in) : Optimization of tolerance allocation of machine elements using non-conventional technique. Mfg Technol Today 2007, 6(2), 25-9.

Development in the tolerance allocation in machine components have undergone significantChanges in the last few years, and these changes may provide new opportunities for getting more profit and to use modern techniques with no compromise in the standard quality. Though there are so many techniques and procedures to maintain quality and to improve quality. Tolerance allocation is an effective tool to allocate the tolerances for the components in the assembly without affecting the functional requirements with the minimum machining cost. It requires the information about individual parts production characteristics, including material cost, production cost and mean shift. Traditionally tolerance allocation in an assembly is obtained by trial and error method. A more scientific approach is often desirable for better performance. In this work, tolerance design optimization of machine elements is taken for analysis. This single objective, non-linear and constrained problem is solved with the new non-conventional technique called Genetic Algorithm (GA). The results are compared with conventional techniques and the performance is analyzed.

1 illus, 2 tables, 11 ref

016563   Manoj Kumar;Sharma S C;Jain A K (Electronics and Computer Science Discipline, DPT, IIT, Roorkee) : Analysis and effect of delay and throughput in mobile ad-hoc networks (IEEE 802.11b) for AODV protocol. J Coop Univ Res Ind Enterpr 2008, 1(2), 16-22.

Reports the simulation results of four different scenarios for MANET having thirty nodes. The performances of proposed networks are evaluated in terms of number of hops per route, delay and throughput with the help of OPNET simulator. Channel speed 2 Mbps and simulation time 600 sim-seconds were taken for all scenarios. The average throughput obtained after simulation from the above data (four scenario) are compared. The average media access delay at node_24 for two routes and at node_22 for four different scenario are compared. It is observed that the throughput will degrade, when it will follow different hops for same source to destination (i.e. it has dropped from 1.45Mbps to 1.32 Mbps which is around 8.9%, and then dropped to 0.48 Mbps which is around 33%). For the above analysis AODV routing protocols have been used. OPNET simulator for design & comprehensive analysis of the MANET with different network scenarios has been used. This can be useful for the people who are working in research laboratory, industry & education in the field of WLAN and wish to use OPNET as a simulator tool to design and analyses the performances of Wireless networks.

6 illus, 3 tables, 8 ref

016562   Kolgane B T;Ankulwar B N (Extension Education Dep, College of Agriculture, Latur, Maharashtra) : Extent of adoption of water management technologies by the beneficiaries and non-beneficiaries of water management project. Agric Update 2008, 3(1-2), 74-8.

Adoption of improved water management practices increases significant saving of water. Keeping this in view, the study was conducted to find out the extent of adoption of selected recommended water management technology by the beneficiaries and non beneficiaries. The study was carried out in Parbhani District of Marathwada region of Maharashtra state. 120 respondents were selected from purposively selected four villages under Operational Research Project area. The data were collected personally with the help of interview schedule. Most of the respondents (75.00 percent of beneficiaries and 66.66 percent of non beneficiaries) belonging to medium level of adoption of water management technologies. Adoption of water management technologies by non beneficiaries was less than beneficiaries. Most of the beneficiaries and non beneficiaries were found lacking in adoption of irrigation schedule and layout, water management at critical stages of crops.

4 tables, 3 ref

016561   Khambalkar V P;Karale D S;Dahatonde S (Non-conventional Energy Soruces and Electrical Engineering Dep, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola, Maharashtra) : Operational characteristics of windmill. Agric Update 2008, 3(1-2), 37-40.

Research work is the analysis of the power curve characteristics of windmill. Turbine power output was observed and analyzed for the actual output of the wind turbine. The various parameter involving in the determination of the power curve of the 1 MW turbine were studied. Power coefficient of the wind turbine was found maximum i.e., 0.42 at the wind speed of 9 m/s. At the rated wind speed (11 m/s) of wind turbine this performance coefficient (Cp) was found to be 0.36. The efficiency at various stages of energy generation was determined for the operation from the power curve.

4 illus, 2 tables, 8 ref

016560   Jadhav H T;Chandiwade U N (Agricultural Engineering Dep, College of Agricultural Engineering and Tehcnology, Dr. Balasaheb Sawa, Dapoli, Ratnagiri, Maharashtra) : Performance testing of box type solar cooker in Konkan region of Maharashtra, India. Agric Update 2008, 3(1-2), 64-5.

In most of developing and under developed countries, different fuels are used for cooking purpose. Free and abundantly available solar energy can be utilized for cooking by solar cooker. The box type solar cooker is the most viable option for cooking different types of food materials. The acceptability of solar cooker depends on various factors. The time required to cook the food material plays an important role in its acceptability in a particular region. In this context performance testing of box type solar cooker was carried at Dapoli in Konkan, a humid and tropical region of Maharashtra. The cooker was tested to cook rice, lantin dal and to boil water simultaneously in three aluminum pots of one-liter capacity each. The average time required to cook 200 gm rice and 100 gm lantin dal were 2 hr 50 minutes and 3 hr 30 minutes respectively. The water boiled in 2 hr. and 30 minutes. The quality of cooked rice and dal were found acceptable for human consumption.

1 table, 3 ref

016559   Gopala Krishna A (Mechanical Engg Dep, J.N.T. University, College of Engineering, Kakinada, Email: agopalakrishna@rediffmail.com) : Global optimization approach to select design and manufacturing tolerances of a mechanical assembly. Mfg Technol Today 2007, 6(3), 27-31.

Allocation of dimensional tolerances directly influences the manufacturing cost and functionality, of a product. The work reports on a procedure to allocate both design and manufacturing tolerances based on the minimum total manufacturing cost of an assembly. The optimization model for tolerance design is a non-linear multivariable problem with multiple constraints. Since such problem may have a noisy surface. there is a need to apply an efficient global optimization technique. In the present work, Scatter search, one of the recently emerged optimization techniques in the area of metaheuristics, is applied successfully to determine . the optimal tolerances. An example is taken from the literature to explain the proposed methodology.

2 illus, 5 tables, 12 ref

016558   Gopal T V;Rajmohan B (School of Mechanical Engg, S.R.M. Institute of Science and Technology, Kattankulathur-603 203, Email: gopaltv@hotmail.com) : Application of ordering genetic algorithm for a milti-criteria optimisation of robotic assembly sequences. Mfg Technol Today 2007, 6(4), 4-8.

Attempts to use the Ordering Genetic Algorithm to generate the optimized sequence for robotic assembly with the following five-optimization criteria: (i) Geometrical Constraints (ii) Number of reorientations (iii) Gripper changes (iv) Subassembly formation (v) Manipulability. The assembly sequence along with the direction of insertion, grippers and subassembly is represented as an individual chromosome in this work. The fitness function is obtained as a weighted sum of the penalties assigned for every poor or undesirable assembly sequence. The idea of penalties allows many criteria to be considered simultaneously. Moreover this notion of penalty will allow one to transform a multi objective optimization problem to a single objective optimization problem. Starting from a randomly initialized population the next generation is evolved using the genetic operators like the modified version of partially matched crossover and mutation. The evolution of subsequent generations converges towards a near-optimal solution. The effectiveness of the proposed method is demonstrated using an example.

3 illus, 5 tables, 9 ref

016557   Fateh Bahadur;Usha Singh (Chemistry Dep, K.N. Govt P.G. College, Gyanpur, Sant Ravidas Nagar, Bhadohi) : Kinetics and mechanism of corrosion of brass in aqueous chlorine solutions. Acta Cienc Indica-Chem 2007, 33(2), 191-6.

Mechanism of Brass corrosion in aqueous solutions containing different concentrations of sodium chloride at 25°C, 35°C and 45°C has been studied by weight loss method in 1 to 3% NaCl solutions for the time of exposure 24 to 168 hours. An attempt has been made to elucidate the mechanism of corrosion by using potentiostatic polarization.

5 illus, 3 tables, 6 ref

016556   Elayaperumal A;Navaneetha Krishnan P; Sivakumar S (Mech Engg Dep, College of Engineering, Anna University, Guindy, Chennai, Email: ep_mal@yahoo.co.in) : Performance analysis and design of plastic chain drive wheel for bicycles. Mfg Technol Today 2007, 6(2), 15-19.

Chain wheel currently being used for bicycles are made up of hot rolled steel and the crank is made up of forged steel, which leads to increase in cost of the product due to rise in market of steel materials. The manufacturing cost is also more because it incorporates lot of machining operations to maintain dimensional accuracy. If the chain-wheels are manufactured with plastic, the productivity can be increased as plastic molding is done for the development. Moreover, the usage of plastic reduces the weight of the component and the dimensional stability can be easily maintained. The model of the plastic chain wheel is developed for analysis. Pro/E is selected for the modeling the Gomponent because it provides an entry-level software solution that lays the perfect groundwork for effective replacement of components. Analysis of a model is carried out to determine the functional parameters like deflection, stress and strain before developing the prototype. ANSYS is a used to analyze the model created by Pro/E tool. After analysis using ANSYS, the model is also analyzed using Pro/E plastic advisor to simulate the flow pattern and enable easy analysis to study the distribution of temperature, pressure drop, fill time and other parameters for the required flow lines and conditions. In-order to increase the productivity, Injection moulding process is selected. Using the Pro/E model the mould is designed. Finally a prototype is developed using Fusion Deposition Modeling (FDM) machine.

13 illus, 1 table, 6 ref

016555   Doloi B;Mitra N S;Mete A K;Bhattacharyya B (Production Engg Dep, Jadavpur University, Kolkata-700 032, Email: bdoloionline@rediffmail.com) : Travelling wire electrochemical discharge machining system development for precision machining of non-conducting materials. Mfg Technol Today 2007, 6(4), 18-22.

Traveling Wire Electrochemical Discharge Machining (TW-ECDM) System has great potential to cut non-conducting engineering hard materials such as ceramics and composites etc. There is also an urgent need for precision machining of engineering ceramics and composites with the development of these materials. Several non-conventional machining processes are available but all of them have inherent difficulties. The traditional method of slicing glass and ceramics, quartz etc. is limited mainly due to high cutting force and requirement of utra-hard tool materials. Hence there is a need to develop an efficient 1!Iethod of cutting and slicing non-conducting engineering materials. Traveling Wire Electrochemical Discharge Machining (TW-ECDM) is an important useful process for this purpose. Present research paper includes the design and development of the experimental setup of total TW-ECDM system which consists of main machining chamber, mechanical hardware modules, electrolyte flow control units and electrical pulsed dc power supply unit. The operation of the developed TWECDM System has been tested after carrying out some experimentation on cutting of Silicon Nitride.

7 illus, 12 ref

016554   Datta S;Bandyopadhyay A;Pal P K (Mechanical Engg Dep, B.P. Poddar Institute of Management & Technology, Kolkata, Email: s_bppimt@yahoo.com) : Mathematical modeling for determining the effects of welding voltage, current, wirefeed rate and traverse speed on bead volume of bead-on-plate weldment in submerged arc. Mfg Technol Today 2007, 6(3), 22-6.

Nonlinear mathematical model has been aimed to develop to reveal the effects of welding voltage, current, wirefeed rate and traverse speed on bead volume of bead-an-plate weldment in submerged arc welding (SAW). Experiments were conducted with different levels of process parameters on M.S. plates to obtain bead-an-plate weld. Important bead geometry parameters like bead width, bead height, and depth of penetration have been measured for each experimental runs. Assuming unit length of the job and bead cross sectional area to be in the form of an circular sector, approximate bead volume has been calculated. All these data have been utilized to develop mathematical model for prediction of bead volume. Multiple linear regression method has been employed to calculate the coefficients of the model. The significance of the coefficients for each of the factors in the models has been calculated by Analysis of Variance Method (ANOVA). The relevant model statistics are also shown. The predictions as given by the model haven been represented graphically to show the influence of the selected process control parameters on bead volume associated with submerged arc weldment.

11 illus, 1 table, 18 ref

016553   Das V J;Vikash Chandra (NO, Vellore Institute of Technology, , Email: vishal.masterbrain@gmail.com) : Study of the effect of weighted exponent on the fuzzy clustering of machine cells. Mfg Technol Today 2007, 6(3), 17-21.

Grouping of machine cells on the basis of parts similarity has been a subject of considerable research interest. Various mathematical modeling and heuristic methods and other clustering methods has been applied. Fuzzy logic in grouping of machines cells is needed when the degree of uncertainaity in placing machine in a particular cell is very high. Fuzzy clustering uses membership values which decide the presence or the degree of membership in a particular cell. This paper investigates the effect of weighted exponent (degree of fuzziness) in using fuzzy clustering algorithm for formation of machine cells. This paper also shows the result of varying the weighted exponent on the robustness of the algorithm.

2 illus, 12 ref

016552   Chakraborty S;Banik D (Production Engg Dep, Jadavpur University, Kolkata-700 032) : Selection of optimal inventory control policy using analytic hierarchy process. Mfg Technol Today 2007, 6(3), 4-11.

Attempt to describe the key features of inventory control system and report a study that utilises the analytic h'ffirarchy process (AHP) technique to evaluate the best policy of inventory control. The study reviews the most important criteria and sub-criteria affecting the selection of the optimal inventory control policy and determines their respective priority values imposing the AHP methodology. Five most popularly used inventory control policies are considered based on knowledge and experience and then subsequently ranked using the AHP under a multi-criteria environment. These considerations together with pair-wise comparison matrices and evaluating methodology lead to prioritize the conflicting criteria for selecting the optimal policy. Sensitivity analysis is also performed to search out the most critical and robust criteria in the inventory control policy selection problem.

3 illus, 11 tables, 10 ref

016551   Bhagyawant R G;Digrase L N;Jadhav S B;Khodke U M;Rautmare L V (NO, College of Agricultural Engineering and Technology, Marathwada Krishi, Parbhani-431 402) : Hydraulic studies of raingun irrigation. Karnataka J agric Sci 2007, 20(2), 446-7.

2 tables

016550   Balasivanandha Prabhu S;Karunamoorthy L (Mechanical Engineering Dep, CEG, Campus, Anna University, Chennai-600 025, Email: sivananda@annauniv.edu) : Influence of sic particle size and solution treatment on properties of al-si based metal matrix composite. Mfg Technol Today 2007, 6(2), 5-9.

Reports the influence of particle size and heat treatment (T6) on some mechanical properties of Al-Si alloy based SiC particulate composites. The T6 heat treatment was carried out to improve the mechanical properties. The heat treatment consists of solution treatment and quenching followed by artificial ageing. After solution treatment and quenching, copper and magnesium rich compounds dissolve in aluminium matrix. The composites produced by stir casting technique were solution treated isothermally at 538°C for 8 hrs to dissolve the precipitates. An electric furnace with a temperature control of ±3°C was used for solution treatment. Ageing was carried out at 155°C for 5 hrs. The mechanical properties such as hardness, tensile strength, failure strain and compressive behaviour have been studied for 9, 11, 15, 40 and 60-micron size particulate added Al-Si (A384) alloy. The fracture behaviour and microstructural aspects were studied from microstructure and SEM photograph.

10 illus, 3 tables, 12 ref

015750   Yiping H;Xiaorong L;Yang C;Yuan H;Guangmei C (Chemical Engineering Dep, Anhuli Univ, Hefei-230 039, Email: chen_gm168@yahoo.com.cn) : Morphology and compatibility in blends of poly(vinyl methyl ether) and poly(ε-caprolactone-block-butadiene) copolymer. Asian J Chem 2007, 19(3), 2107-16.

The morphology and compatibility of the poly(vinyl methyl ether) (PVME) with poly(e-carpolactone-block-butadiene) copoly-mer (PCL-b-PB) have been studied by polarized light microscope (PLM), differentia! scanning calorimetry (DSC) and Fourier transform infrared (FTIR). In the PVME/PCL-b-PB blends, ring-banded spherulites have been observed at various compositions and crystallization temperatures from 33 to 42øC. The FTIR studies revealed that some weak interaction existed between PVME and the PCL-b-PB. The thermal analysis displayed the blends presented , a single glass transition temperature (Tg) at each composition. The fraction of PCL that crystallized in the blends increased with increasing the PVME content up to about 40 wt<37<>F255> of PVME. The crystallization ability of PCL block in the blends was affected by PVME content. The dSC results indicated that PVME was partially compatible with the PCL-b-PB. The existence of some weak interaction and partial compatibility in the PVME/PCL-b-PB blends had influence on the formation of PCL ring-banded spherulites. Moreover, the existence of PB block affected the crystallization behaviour of PCL.

4 illus, 1 table, 12 ref

015749   Yalcin M G;Ucgun F;Unal B (Geological Engineering Dep, Faculty of Engineering and Architecture, Nigde Univ, 51200 Nigde, Turkey) : Application of an artifical intelligence to the estimation of water quality parameters: water quality of Nigde creek water, Turkey. Asian J Chem 2007, 19(3), 2325-34.

Artificial intelligence is used for the estimation of water quality parameters of N'igde creek in the central part of Turkey. Nigde creek basin contains the two largest region of Turkey which is Nigde city and Bor district. Moreover, it is the major agricultural area in the region as well as highly agricultural and industrialized. In this study, analyses have been conducted on water samples taken from five stations located along the Nigde creek. Hydro-chemical analyses have been conducted on the water samples, the results have been evaluated according to water quality parameters. The laboratory data with an artificial neural network computer program called clean water quality program-CWQP, which is designed according to water quality parameters, its place has been defined among the classifications of water quality. Quality parameters used have been prepared in compliance to the In-continent surface water classification as stated in the regulation of water pollution and checking for Turkey. Accordingly, water quality has been classified in four groups as Quality I, II, III and IV. Selection of appropriate input parameters to estimate another one is key to use ANN. This is essential to obtain maximum success with minimum error. The input parameters selected must be those which affect most the output one. In this study, therefore, water quality at five stations has been determined to be of Class IV water quality with CWQP. Furthermore, lead has stepped up as the most important polluter in the analyses, which has the negative effects on water quality in all stations and precautions are needed to be taken to protect Nigde creek. Results obtained from the CWQP have been discovered to be indifferent from the ones obtained through the classical methods, implying their availability for use comfortably in water pollution areas. This program has ensured rapid results and non-specialized study in determining the water quality.

6 illus, 1 table, 16 ref

015748   Tandon K M;Gupta M K;Gupta S N (Shriam Fertilisers and Chemicals, , Shriram Nagar, Kota-324 004) : Ammonia synthesis converter repair and catalyst replacement at SFC, Kota. Indian J Fertil 2007, 3(3), 61-7.

Ammonia Synthesis Converter is a critical equipment for the ammonia plant. The internals of the converter are subjected to high temperature and nitriding atmosphere during operation. These are severe conditions of operation leading to accelerated failure of thinner parts of the converter basket. Describes the problems faced during the recent catalyst change out in Aug.l Sep. '06 and the repairs carried out in the basket.

11 illus, 1 ref

015747   Sinha A K;Misra A;Shah C N (NO, Indian Farmers Fertiliser Cooperative Ltd., Kalol Unit, P.O. Kasturinagar, Distt Gandhinagar-382 423) : Experiences of the energy saving project at IFFCO Kalol. Indian J Fertil 2007, 3(3), 45-51.

Keeping abreast of technological advancements through plant upgrades has been the key to IFFCO's success. Modernisation of all its plants for improving energy efficiency, productivity, safety and operating reliability has been a continuous process at IFFCO. In 2003, IFFCO embarked on an ambitious Energy Saving Project (ESP) in its five Ammonia Plants at Kalol, Phulpur and Aonla. This paper illustrates the plan and successful commissioning of the envisioned energy saving revamp project of the 1974-vintage Ammonia Plant at IFFCO Kalol Unit, and highlights the experiences of implementa tion of the selected energy saving schemes in phased manner.

4 illus, 6 tables

015746   Sham Sundar K M;Manjunath N T (Studies in Civil Engng, Univ B.D.T. Coll of Engng, Davangere-577 004) : Phenomenon of granulation process in UASB reactor. J envir Prot 2007, 27(9), 775-81.

The aim of this study is to examine sludge granulation during the anaerobic treatment of wastewater. The wastewater used is diluted molasses, to a value ranging between 1250 to 12.500 mg/L. Flocculated sludge, cultivated on distillery wastewater in an anaerobic digester with TS content 137.75 g/L and VS of 81.23 g/L is used as a seed. Percentage VS content in general increased and maximum value of 65.57% is observed on 79th day. An UASB reactor was operated at a constant HRT, of 20 h, while the OLR ranged between 1.51 to 15.05 kg-COD/m3.d. The granules of spherical shape of size of about 3 mm was observed after 80 days of operation at an OLR of 15 kg-COD/m3.d. The maximum COD removal of 73.25% was observed at a maximum OLR of 15 kg COD/m3.d.

12 illus, 4 tables, 16 ref

015745   Rezai B;Pazoki A (Mining Dep, Metallurgy and Petroleum Engng, Amirkabir Univ of Technol) : Agitation leaching of gold with thiourea and cyanidation methods. Indian Mineralogist 2007, 41(1), 84-9.

The preliminary laboratory tests to identify the relative agitation leaching response to cyanidation and thiourea leaching of an oxidized ore have been carried out. The ore deposits of Neishaboor area in Iran with gold grade of 4 ppm are rich enough for beneficiation studies. Charecterization studies show that, the ore is oxidized and gold is present partly in the form of solution in quartz veins as well as in the form of free particles in iron hydroxide specially haematite which is the product of pyrite oxidation. Quartz, haematite, calcite and feldspar are the main minerals present in the order of abundance. Sieve analysis and distribution of gold particles in different sieve fractions show gold particles are distributed below 2000 microns. Based on characterization studies, the potential of an alternative lixiviant like thiourea and cyanide leach have been determined and found that under optimized conditions thiourea leaching of the ore performs (extraction of 96.7% after l6 hours) is better than cyanide leaching (extraction of 47.3 after 16 hours).

3 illus, 6 tables, 6 ref

015744   Reshma S;Prakasam V R (Envir Sci, Univ of Kerala, Kariavattom, Thiruvananthapuram-695 581) : Potability of tube wells of Mayyanad panchayat of Kerala. Indian J envir Prot 2007, 12(11), 1015-18.

In Mayyanad panchayat of Kerala, drinking water is supplied by Kerala Water Authority through pipelines from 8 tube wells drilled for the purpose. An analysis of water quality showed that the mean water pH was 6.72, the colour and the iron content were above desirable limit and the total and faecal coliform counts were above desirable.limit and permissible limits. But the water was partially clean, as indicated by the WQI. Steps should be, however, taken to remove the coliforms and excess iron.

2 tables, 8 ref

015743   Pathak S S;Sharma A;Jha B K;Khanna A S (Metallurgical Engineering & Materials Science, Indian Institute to Technology, Bomay, Powai-400 076, Email: sspathak@iitb.ac.in) : Novel waterborn nanostructured coatings. Asian J expl Sci 2008, 22(2), 187-8.

Use of nanostructure sol-gel coating and their further modification with organic polymer have to be regarded as a consistence further development of the new innovative sol-gel technology which is characterized by the combination of novel and conventional method of the formulation of coatings. These coatings are environmentally-friendly coatings of a new era of high technology for protection of material from environmental stresses and to get preferred properties.

^ssc

015742   Nijagunappa R;Shekhar S;Gurugnanam B;Raju P L;De P (Studies and Res Envir Sci Dep, Gulbarga Univ, II Floor, Karya Soudha, Gulbarga-585 106, Email: nijagunappa123@rediffmail.com) : Road network analysis of Dehradun city using high resolution satellite data and GIS. J Indian Soc Remote Sens 2007, 35(3), 267-74.

4 illus, 11 ref

015741   Nigam N C;Maheshwari A K;Puri R (Indian Farmers Fertiliser Coop Ltd., , Aonia Unit, PO Iffco Township, Paul Pothen Nagar, Bareilly-243 403) : Energy saving project in ammonial-II plant at IFFCO Aonla unit. Indian J Fertil 2007, 3(3), 71-6.

IFFCO, a premier fertiliser company has implemented energy saving schemes in ammonia plant-II at IFFCO Aonla unit for reducing the energy consumption under energy saving project. Describes the experience of IFFCO Aonla unit for implementation of the energy saving project, from conceptualisation up to successful commissioning of the schemes.

6 illus, 1 table

015740   Nagarajan P;Isaiah S;Viji Saral Elezabeth D (PG and Res Chem Dep, Bishop Heber Coll, Trichy-620 017) : Pseudo second order model for cadmium ion sorption from aqueous solutions on to leucaena glauca benth. J envir Prot 2007, 27(9), 789-98.

The acid processed Leucaena Glauca Benth was successfully utilized for the removal of cadmium (II) from aqueous solution. The adsorbent was characterized by FT IR, SEM, X ray florescence spectrometer. The sorption data have been analyzed and fitted to linearised isotherms of the Freundlich, Langmuir and Redlich -Peterson models. The batch sorption kinetics have been tested for pseudo first order, second order reaction models. The rate constants of adsorption for these kinetic models and also the intra particle diffusion parameters were calculated. Film diffusion coefficient and pore diffusion coefficient calculated indicates that the film diffusion was the rate limiting step.

6 illus, 4 tables, 38 ref

015739   Muthu Manoharan R;Senthil Nayagam P (Southern Petrochemical Industries Corpn, , Spicnagar, Tuticorin-628 005) : Debottlenecking of a vintage phos acid plant to improve the reliability and reduce energy. Indian J Fertil 2007, 3(3), 39-42.

Conventional practice followed for augmentation of the plant is to go for change in technology with the help of the process licensor. Considering the huge capital cost required for such a revamp, it was decided to retain the same technology and take up debottlenecking of identified systems and equipments as and when opportunity arises. After a series of brainstorming sessions, the targeted plant capacity was fixed as 500 mt/day, without compromising on P₂O₅ recovery efficiency. The paper explains the milestones crossed and future road map to achieve the targeted capacity.

3 illus

015738   Kumbhar N T;Bhanumurthy K (Materials Science Div, Bhabha Atomic Research Centre, Trombay, Mumbai-400 085) : Friction stir welding of Al 6061 alloy. Asian J expl Sci 2008, 22(2), 63-74.

Friction stir welding, a solid state joining technique, is widely being used for joining Al alloys for aerospace, marine automotive and many other applications of commercial importance. FSW trials were carried out using a vertical milling machine on AI 6061 alloy. The tool geometry was carefully chosen and fabricated to have a nearly flat welded interface. Important process parameters that control the quality of the weld are a) axial force b) rotation speed (rpm) c) traverse speed (mm/min) and d) tool tilt angle and these process parameters were optimized to obtain defect free welded joints. It is observed that, during the friction stir welding, extensive deformation is experienced at the nugget zone and the evolved microstructure strongly affects the mechanical properties of the joint. The present studies aimed to understand the microstructural changes and the associated mechanical properties during the FSW and also after post weld heat treatment (PWHT). The resultant microstructure was characterized using electron probe microanalysis (EPMA), secondary electron microscopy (SEM) and orientation imaging microscopy (OIM). This paper presents the optimization of process parameters and also highlights the influence of PWHT on the microstructure, composition variation across the interface and mechanical properties of FSW 6061 Al alloy.

7 illus, 2 tables, 19 ref