007889   Bishnoi N R;Khumukcham R K;Rajender Kumar (Dep of Envir Sci and Engng, Guru Jambheshwar Univ, Hisar-125 001, Email: nrbishnoi@gmail.com) : Biodegradation of pulp and paper mill effluent using anaerobic followed by aerobic digestion. J envir Biol 2006, 27(2), 405-8.

Degradability of black liquor of pulp and paper mill wastewater for biomethanogenesis in continuous stirred tank reactor (CSTR) and followed by activated sludge process (ASP) has been carried out. Continuous stirred tank reactor was used in study for anaerobic digestion of black liquor, while completely mixed activated sludge system was used for aerobic digestion. A maximum methane production was found upto 430ml/day, chemical oxygen demand was reduced upto 64% and total volatile fatty acid increased upto 1500mg/l from 975mg/l at 7.3 pH, 37 °C temperature and 8 days hydraulic retention time during anaerobic digestion. In activated sludge process (aerobic digestion) chemical oxygen demand and biological oxygen demand reduction were 81% and 86% respectively at 72 hr hydraulic retention time.

5 tables, 15 ref

007888   Bhattacharya D (Div of Electroceramics, Cent Glass and Ceram Res Inst, Kolkata-700 032, Email: dipte@ncgcri.res.in ) : Magnetoresistivity in solids. Trans Indian Ceramic Soc 2006, 65(1), 1-16.

Phenomenon of magnetoresistivity is known since the days of Michael Faraday when he observed nearly 1-2% change in electrical resistivity under a magnetic field in glassy materials. Over the years, while new materials with varying degrees of magnetoresistivity have been developed, the quest for unearthing the mechanism, side by side, led to the formulation of new theories for more complex materials with complicated electronic band structure courtsey local magnetic interaction and strong correlation. Following Kramer's concept of indirect magnetic exchange interaction, the formulation of double exchange interaction theory in the 1950s, by Zener, Anderson, and de Gennes, created a perspective for analyzing the correlation between metallic charge conduction and ferromagnetism and hence a sizable magnetoresistivity - observed in a series of transition metal oxides with different crystallographic structures. During the last one and a half decade, a series of unusual and unexpected observations have been made in different compounds - (a) giant negative magnetoresistivity in magnetic multilayers, (b) even higher and therefore colossal magnetoresistivity in single phase doped LaMnO₃ based compounds, (c) melting of a certain charge state under a magnetic field, (d) magnetic field driven structural phase transition and a large change in resistivity thereby, to name just a few. This review discusses the traditional concepts starting from classical Hall effect to domain boundary interaction to Ruderman-Kittel-Kasuya-Yosida (RKKY) mechanism and places the more recent developments against the backdrop of old concepts. It also looks beyond double exchange plus Jahn-Teller effect into the modern theory of finer scale intrinsic phase separation and percolation conduction as the most probable scenario for describing the magnetoresistivity in various transition metal oxides. The limited application potential of magnetoresistivity seems to have now become unlimited with the jump in the magnitude of magnetoresistivity. This review presents a few glimpses of new possibilities and future scopes.

^iia13 illus, 78 ref

007887   Athar M (Dep of Civ Engng., Z.H. Coll of Engng. and Tech. A.M.U., Aligarh) : Discharge equations for uncalibrated sharp edged orifice plates. ISH J Hydraul Engng 2006, 12(1), 1-12.

The experimental results about the discharge equations developed for uncalibrated sharp edged orifice plates in a closed conduit have been presented. The data collected in the laboratory for various shapes of the orifice plates with varying area ratios have been analyzed to yield discharge equations. The discharges computed with developed discharge equations are compared with the measured discharge in the laboratory and it is found in a good agreement.

12 illus, 13 ref

007886   Alkan G B (Dep of Maritime Transp and Mgmt Engng Fac of Engng, Istanbul Univ, Istanbul, Turkey, Email: ilginkur@istanbul.edu.tr) : Impact of caspian crude oil on turkish straits. Asian J Chem 2006, 18(3), 2047-60.

The Turkish Straits, for the last 10 years at least, have turned into one of the key shipping foci of the world seaborne oil trade, such as the Suez Canal, the Strait of Malacca and the Strait of Dover. It was previously the same in 1892. In that year, oil cargoes loaded in the Black Sea port Batumi were delivered by tankers to their customers in the Far East destination(s), all passing through the Turkish Straits. Nearly 123 million tons of oil passed through the Strait of Istanbul in 2002, representing 5 per cent of the oil traded by sea. The number of crude carriers that passed through the Strait for that period, up or down, was 6022. In other words, 15 crude oil carriers a day sailed through the Bosphorus, laden or in ballast. Similarly, 1330 tankers carrying LPG and chemicals also used the Strait, meaning 4 additional but smaller size tankers a day on top of the above figure. Shipping traffic in the Strait was 4125 transits in the year 1841 and almost tripled in 1856, during the Crimean War. There are now an average of 25.000 transits per year in each direction including, inter alia, tankers, chemicals, product tankers, LNG and LPG carriers-the largest size passing through being 150 to 160.000 tonners fully laden or vessels of around 300 m in length partly laden. Almost one-third of the total transits are the local ships passing through the Strait. Also provides an overview of the impact of Caspian crude on Turkish Straits and also explains the geographical location of Turkish Straits and includes lines that connect to Caspian crude.

3 illus, 5 tables, 9 ref

007885   Alam J (Dep of Civ Engng, Zakir Hussain Coll of Engng and Technol AMU, Aligarh) : Seepage and strength characteristics of fly-ash sand mixtures: an experimental study. ISH J Hydraul Engng 2006, 12(1), 52-9.

An effort has been made to produce a low permeable mass by mixing fly-ash and sand in different proportions. Present paper is an attempt to study the effect of fly-ash in reducing the permeability of sand beds. The sand beds are highly permeable as compared to fly-ash (Parua, P. K., 1996). As a case study fly-ash has been collected from Dadri thermal power station situated in U.P. In an attempt to increase the seepage resistivity of sand beds, the fly-ash has been mixed in various percentages (0-100%) with fine sand and coarse sand. The study reveals that in case of fine sand minimum permeability is observed at 80% fly-ash, whereas in case of coarse sand it occurs at 60% fly-ash for a constant porosity of 40%. However, the minimum value of permeability achieved in case of coarse sand at 60% fly-ash is 21% less than the minimum permeability achieved in case of fine sand at 80% fly-ash.

5 illus, 1 table, 11 ref

006763   Ziliukas A (Dep of Mechanics of Solids, Kaunas Univ of Technol, Kestucio str. 27, Kaunas LT-44025, Lithuania, Email: antanas.ziliukas@ktu.lt) : Strength criterion of unidirectional composite. Indian J Engng Mater Sci 2006, 13(6), 520-4.

Large number of experimental data is required to assess the strength of composite materials in respect to their anisotropy level and impact of complex stressed state, especially when the values of this parameter are defined in different directions. An attempt has been made to reduce the number of testing methods for plain composite elements. The later simplification follows from the theoretical interpretation of stress tensor.

2 illus, 3 tables, 9 ref

006762   Zaimoglu Z (Dep of Envir Engng, Univ of Cukurova Fac of Engineering-Arch. 01330, Balcali-Adana, Turkey, Email: zeynepz@cu.edu.tr) : Treatment of campus wastewater by a pilot-scale constructed wetland utilizing Typha Latifolia, Juncus Acutus and lris versicolor. J envir Biol 2006, 27(2), 293-5.

Constructed wetland is a popular treatment method for different sources of wastewaters, being an alternative to conventional wastewater treatment methods that have operational and financial restrictions, especially for decentralized wastewater systems. A pilot-scale, continuous flow, subsurface flow wetland was constructed at the Cukurova University in Adana, Turkey. The system works on a multi-culture planting texture employing Typha latifolia, Junkus acutus and Iris versicolor. Removal efficiency of the system was observed for approximately one year with 1.2 m³/h steady inflow rate. Removal rates of 89.0 ± 10.6%, 76.7 ± 8,3% and 68.8 ± 5.9% were achieved for TSS, COD and BOD₅, respectively. A high removal (95.4 ± 8.3%) for fecal coliform was also observed. The obtained results imply that constructed wetlands are suitable for treatment of wastewaters originating from campuses in arid climate.

3 illus, 2 tables, 17 ref

006761   Yildirim S (Dep of Mechanical Engng Fac of Engng, Erciyes Univ, 38039, Kayseri, Turkiye, Email: sahiny@erciyes.edu.tr) : Four legged walking robot control using neural networks. J scient ind Res 2006, 65(11), 887-93.

Neural network (NN) control of planar four-legged walking robot has been presented. The control system consists of a neural controller, standard PD controller and walking robot. Proposed NN is employed as an inverse controller of the robot. In addition to feedforward connections from the input layer to the hidden layer and from the hidden layer to the output layer, there is also feedback connection from the output layer to the hidden layer and from the hidden layer to itself. The reason to use hybrid layer is that robot's dynamics consists of linear and non-linear parts. The results show good performance of the proposed neural and control schemes.

8 illus, 2 tables 8 ref

006760   Wang X;Wang C;Jin S;Chen H (Coll of Chem Engng, Qingdao Univ of Sci and Technol, Qingdao, 266042, China, Email: dawazm@sohu.com) : Optimal operating conditions for reactor-separator-recycle system. J scient ind Res 2006, 65(11), 867-72.

Characteristic equation (CE) for the Reactor-Separator-Recycle (RSR) system is obtained using geometrical methods. Total yield is selected as the objective function of the complex reaction in two-dimensional concentration space. CE for RSR system can be separated into Plug Flow Reactor (PFR) and Continuous Stirred-Tank Reactor (CSTR) based CEs. By combining CE curves of RSR system with the attainable region boundary curves, optimal operating conditions of RSR system for maximal total yield can be conveniently determined. Besides consecutive reaction, application of CE for RSR system can also be extended to other kinds of complex reaction processes.

8 illus, 2 tables, 12 ref

006759   Vijayakumar B;George T;Rajan P S;Kumar M; Rajan M P (Bhabha Atom Res Cent Envir Surv Lab Kudankulam Nuclear Pwr Project Hlt, , Anu Vijay Township-627 120) : Fluidized bed bio reactor sewage treatment system and wastewater quality at Kudankulam. Indian J envir Prot 2006, 26(5), 419-24.

With the availability of fresh water becoming exiguous in certain coastal belts, it has become imperative to manage water resources in a resourceful and judicious manner. The focus has also shifted to minimum or zero tolerance from existing waste treatment plants so as not to contaminate or pollute the already shrinking drinking water resources. Many of the modern waste treatment approaches are already aiming at zero discharge with a view to conserving the ecological balance and to protect the rich bio diversity, flora and fauna. Describes one scuh domestic sewage treatment system called Fluidized Bed Bio Reactor operating in the residential colony and plant site area of Kudankulam Nuclear Power Project. Wastewater quality of the resulting effluent water has also discussed.

2 illus, 3 tables, 6 ref

006758   Verma A K;Singh S N;Seshadri V (Dep of Civ Engng, Kamla Nehru Inst of Technol, Sultanpur-228 118, Email: sidhnathsingh@hotmail.com) : Pressure drop for the flow of high concentration solid-liquid mixture across 90degree horizontal conventional circular pipe bend. Indian J Engng Mater Sci 2006, 13(6), 477-83.

Pressure drop across a 90° horizontal bend for fly ash slurry at high concentrations is reported. The pressure drop across the bend has been measured at five concentrations in the range of 50-65% (by weight) and the data has been analyzed to obtain the relative pressure drop, bend loss coefficient and permanent pressure loss. Measurements show that the relative pressure drop across the pipe bends increases with increase in concentration at low velocity. However, at any given concentration relative pressure drop is independent of velocity over the range tested. The bend loss coefficient at any velocity increases with increase in concentration. The permanent pressure loss increases marginally with concentration and velocity. The contribution of disturbed flow conditions downstream of the bend to the total pressure loss is much less in the case of highly concentrated slurries as compared to that in water.

9 illus, 1 table, 13 ref

006757   Venkateswara Rao V (Natn Metall Lab, , Jamshedpur-831 011, Email: vvrao_ind@rediffmail.com) : A structural study of copper-43at% cadmium alloy. Indian J Engng Mater Sci 2006, 13(6), 531-4.

Cu-43at%Cd alloy was solidified at different cooling rates ranging from 10⁰ to 10⁶ K/s. For rapid solidification, (cooling rate <126>10⁶ K/s), a modified gun splat cooling technique was employed. Metastable crystalline and amorphous phases were obtained. Solid-state transformation of the alloy into equilibrium Cu₄Cd₃ was accelerated on increasing the cooling rate.

5 illus, 1 table, 13 ref

006756   Vasudevan P;Padmavathy V;Dhingra S C (Cent for Rur Dev and Technol, Indian Inst of Technol Delhi, New Delhi-110 016, Email: padmav10@hotmail.com) : Cadmium (II) ion and nickel (II) ion biosorption on yeast: application of equilibrium model. J scient ind Res 2006, 65(12), 1013-17.

Experimental data on cadmium (II) and nickel (II) ion sorption on deactivated protonated yeast over a wide range of sorbent and initial metal concentrations, were analyzed by an equilibrium model based on a thermodynamics approach. Model describes relationships between the equilibrium concentration of metal, metal sorption per unit biomass dosage and concentration of sorbent and initial metal concentrations at constant pH and temperature. It is not found possible to reasonably fit the sorption data for cadmium (II) and nickel (II) ion on deactivated protonated yeast, to a unique isotherm curve when both initial metal ion concentration and biomass concentration are varied at a particular pH. Model fits the data well for the sorption of nickel (II) ion onto deactivated protonated yeast at pH 6.75. However, model could be applied only for a given substrate concentration for sorption of cadmium (II) ion onto sodium form of deactivated protonated yeast at pH 6.5.

4 illus, 2 tables, 14 ref

006755   Ucbeyiay H;Ozkan A (Dep of Min Engng, Selcuk Univ, Konya, Turkey, Email: alpozkan@selcuk.edu.tr) : Hydrophobic flocculation characteristics of calcite and effects of some inorganic dispersants. Indian J chem Technol 2006, 13(5), 448-54.

Hydrophobic flocculation characteristics of calcite mineral were investigated using sodium dodecyl sulphate (SDS) and Aero 845. Calcite suspensions could be flocculated by these anionic surfactants in the pH range of 9.3-11.5. Especially SDS was more effective on the calcite suspensions at pH values lower than 10.5. The flocculation of calcite with SDS and Aero 845 increased rapidly with increasing surfactant concentration. However, it started to decrease at concentrations higher than 30 mg/L for Aero 845 and 50 mg/L for SDS. It was found that the maximum aggregation degree of calcite particles could be achieved with a stirring speed of 500 rpm and a flocculation time of 3 min. The effects of sodium silicate, sodium polyphosphate and sodium phosphate, used as inorganic dispersants, on the flocculation of calcite were also studied. In the presence of sodium silicate and sodium polyphosphate, the flocculation power values obtained with both surfactants decreased with increasing dispersant concentration till approximately 0.5 and 1 g/L concentrations, respectively. Also, the flocculation of calcite with Aero 845 and SDS decreased towards 0.5 and 1 g/L concentrations of sodium phosphate, respectively. At higher dispersant concentrations, these power values remained relatively constant for sodium silicate, and different effects were also observed for other dispersants depending on surfactant type used in the experiments. In addition, it was found that sodium silicate was more effective to disperse the calcite suspensions with SDS and Aero 845.

8 illus, 29 ref

006754   Suresha B;Chandramohan G;Sadananda Rao P R; Sampathkumaran P;Seetharamu S;Venkateswarlu V (Dep of Mechanical Engng, PSG Coll of Technol, Coimbatore-641 004, Email: sureshab2004@yahoo.co.in) : Friction and slide wear characteristics of glass-epoxy and glass-epoxy filled with SiCp composites. Indian J Engng Mater Sci 2006, 13(6), 535-41.

Highlights the friction and wear behaviour of glass-epoxy (G-E) composites with and without silicon carbide particles (SiCp) filler content as a function of sliding distance, keeping the sliding velocity and applied load constant it is seen that the wear rate increases with increasing sliding distance, but the gradient is not maintained the same all through. An attempt has also been made to correlate the wear loss of the worn surfaces using scanning electron microscopic (SEM) observations. The coefficient of friction is found to be almost same over a wide range of sliding distance employed. Further, the study indicates that the SiCp-G-E composites show lower coefficient of friction and lower slide wear loss compared to G-E composites irrespective of the sliding distance employed. It is found that during the running in wear, the wear of the resin mix as well as very few broken fibers are noticed. The breakage of fibers, the matrix debris formation and interface separation take place at a much later stage (i.e., in the severe wear region). In the steady state region some of the broken fibers are getting disoriented in the matrix and also agglomerations of the debris are seen. Other interesting SEM features have been noticed and discussed taking into account the addition of SiCp filler content (2.5 and 5.0 wt. %).

16 illus, 3 tables, 20 ref

006753   Srinath A;Rao A C (Mechanical Engng, P.V.P. Sigghardha Inst of Technol, Kanuru, Vijayawada, A.P., Email: sssit@rediffmail.com) : Susceptibility of planetary gear trains to clearances and misalignments. Indian J Engng Mater Sci 2006, 13(6), 489-93.

Clearances and misalignments alter the performance of kinematic chains and gear trains. Errors are usually classified as position error and transmission error, position error is the error in angular position with respect to the ideal position. Backlashes in gear trains and joint clearances in linkages produce position error while the transmission error is caused by the misalignment. The gear trains may have self-locking tendencies (similar to singular positions in linkages). There are a huge number of distinct linkages and planetary gear trains with specified number of links and degree-of-freedom. Hence, it is necessary to compare them in order to select the best possible chains or gear trains. An attempt is made to compare distinct gear trains from the view points of position and transmission errors.

4 illus, 8 ref

006752   Singhai J;Singhai R (Electron Dep, MANIT, Bhopal, Email: j_singhai@rediffmail.com) : MSVQ: A data compression technique for multimedia applications. J scient ind Res 2006, 65(12), 982-5.

Data compression is one of the enabling technologies for the application of communication technology with ever growing Internet, explosive development of mobile communication and the ever-increasing impact of. video communication to store the data in a compact way for minimum cost of storage and transmission. There are various compression techniques available which are capable of application specific large compression ratios. The Multi Stage Vector Quantization (MSVQ) based on LBG algorithm and Partial Distance Search (PDS) method, which is most suitable for faster encoding required in multimedia applications.

5 illus, 4 tables, 7 ref

006751   Singh S N;Seshadri V;Singh R K;Mishra T (Dep of Appl Mechanics, IIT, New Delhi-110 016, Email: sidhnathsingh@hotmail.com) : Flow characteristics of an annular gas turbine combustor model for reacting flows using CFD. J scient ind Res 2006, 65(11), 921-34.

Computational Fluid Dynamics (CFD) approach can reduce the expenses as well as time to provide an insight into the characteristics of flow and combustion process inside combustion chamber at design stage. Geometry of combustor simulated for present investigation is a 45° sector of an annular combustor. Primary, secondary and dilution holes are simulated on the inner and outer liner walls with swirler being placed at the center of the liner dome. Flow has been analyzed in the annulus region. The results are fed as input for the flow analysis in the liner. Uniform velocity distribution is obtained in the annulus passage around the liner. For the liner flow, it is observed that on moving axially from nozzle to outlet, velocity and temperature contours become more uniform and symmetric in circumferential plane. Mass fraction of CH₄ and O₂ decreases whereas concentration of CO₂, NO and H₂O increases in the axial direction (nozzle to outlet).

12 illus, 1 table, 21 ref

006750   Singh K;Acharya S A;Bhoga S S (NO, Amaravati Univ, Amaravati-444 602, Email: saha275@yahoo.com) : Glycine-nitrates combustion synthesis and properties of nano-sized Ce_1-x Gd_xO₂-delta solid solution for solid oxide fuel cell viewpoint. Indian J Engng Mater Sci 2006, 13(6), 525-30.

Nanocrystalline gadolinium-doped ceria powders for solid electrolytes have been successfully prepared via glycine nitrate combustion synthesis and characterized by TGA/DTA, XRD) and SEM. Using these powders; highly dense ceramics have been prepared by sintering at 1100°C which is much lower temperature than 1600°C usually required for ceria solid electrolytes prepared by conventional ceramic technique. The effect of compositions on structure and conductivity has also been studied.

8 illus, 1 table, 23 ref

006749   Shrivastava G P;Shukla J P;Gupta M (NO, Lucknow Univ, Lucknow) : Variation of dielectric constant and emissivity of soil with temperature. Ultra Scient phys Sci 2006, 18(1), 59-64.

Dielectric constant of soil varies with the moisture content present in the soil and also with the variation in temperature. Natural objects, such as soil at absolute temperature are capable of emission and absorption. The emitted radiation from the soil depends on its dielectric constant, surface roughness, physical temperature and angle of observation. The emissivity of soil also varies with the moisture content. Values of dielectric constant would help in calculating the emissivity and also in development of active and passive remote sensing sensors. Characteristics of soil at sub-zero temperature change and create a frost in the soil. The occurrence of frost in the ground depends on large number of interrelations between air temperature, soil type, moisture content, vegetation cover, snow and other factors. Dielectric measurements have been carried out for dry and wet soil. The dielectric constant has been found to increase with moisture content and temperature. At sub zero temperature, some ice particles have been observed at the surface of the soil sample. Emissivity can be evaluated with the help of dielectric constant for the dry and wet soil.

3 illus, 15 ref

006748   Sharma R;Chhalotra G P;Tiwary S K;Chhalotra N (NO, Royal Bhutan Inst of Technol Phuentsholing, Bhutan, Email: drvavindrasharma@yahoo.com) : A study of electroluminescent materials and their reliability attributes under their applications. Ultra Scient phys Sci 2006, 18(1), 15-24.

Electroluminescent materials have several applications in Electrical and Electronic Engineering. It is essential to collect information on these materials and devices: thin film, single crystal and semiconductors diodes. A general study of Electroluminescent materials is made to find their reliability and applicability. A list of references is collected to review them and analysis is made on them on the ground of theoretical models of material parameters. The merit of such devices is that they can work, on 2V supply at a current of 1 AMP/cm. The life may be equal to a fluorescent tube light of the order of 1000 hours. Large number of statements and experiment results are collected to verify them in the fuzzy space and their fuzzy grades of truth are represented. The failure rates are estimated. The risk, hazard, danger, calamity or disaster may be found in the complementary space of the reliability. This study is made in nine tables forming fuzzy sets and their complementary fuzzy set to discuss the union and intersection and fuzziness in the devices. The devices are not reliable and have a short life with a great hazard and danger due to light emitting systems.

2 illus, 9 tables, 17 ref

006747   Sengupta R N;Kaur J;Jagdish Kumar (Cent, Scientific Instruments Organisation, Sector 30, Chandigarh-160 030, Email: jaspreet_k123@rediffmail.com) : Design and development of microcontroller based human airway pressure measurement system with real time graphical display for anaesthesia ventilator. J scient ind Res 2006, 65(12), 986-91.

Microcontroller based hardware design and system software associated with the graphical visualization or the airway pressure data acquisition system has been designed and developed, and successfully incorporated in indigenous prototype of anaesthesia ventilator. An inexpensive airway pressure monitoring system based around 80C31 microcontroller with RAM, EPROM, AD574 ADC, peripheral interface devices and graphical LCD etc., is a module of the indigenously developed instrument. What has been envisaged here is to get a real time pressure waveform on LCD. Air pressure changes over a " respiratory cycle. This makes anaesthetist to have a feeling of how air pressure in the tract changes with time. An accurate and sensitive piezoresistive type of air pressure sensor has been used outside the mouth and inside the piping.

6 illus, 1 table, 8 ref

006746   Rao H S;Ramesh Babu B (Dep of Civ Engng, JNTU Coll of Engng, Anantapur-515 002, Email: hanchate123@yahoo.co.in) : Optimized column design using genetic algorithm based neural networks. Indian J Engng Mater Sci 2006, 13(6), 503-11.

In the structural design of columns, the dimensions of the column and reinforcement are initially assumed and then the interaction formula is used to verify the suitability of chosen dimensions and reinforcement. This approach necessitates few trials for coming up with an economical and safe design. Demonstrates the applicability of artificial neural networks (ANN) and genetic algorithms (GA) for the design of short columns under biaxial bending. A hybrid neural network model that combines the features of feed forward neural networks and genetic algorithms has been developed for the design of short column subjected to biaxial bending. The network has been trained with design data obtained from design experts in the field. The hybrid neural network model learned the design of column in just 1800 training cycles. After successful learning, the model predicted the percentage of steel required for new problems with good accuracy satisfying all design constraints. The results of the hybrid network model are compared with the solution of an optimizer, which uses the interior penalty function method. The various stages involved in the development of genetic algorithm based neural network model are addressed.

6 illus, 3 tables, 28 ref

006745   Ramarethinam S;Anitha G R;Latha K (NO, The United Nilgiri Tea Estates Co Ltd., Race Course, Coimbatore-641 018, Email: untea@vsnl.com) : Standardization of conditions for effective clarification and concentration of green tea extract by membrane filtration. J scient ind Res 2006, 65(10), 821-5.

Clarification of tea extracts with membrane filters was carried out, as a mode of concentration, of the soluble components of tea, prior to drying to reduce creaming in tea based products. The reduction of flux rate was high in reverse osmosis membranes microfiltration compared to ultrafiltration and prefiltration enabled removal of mainly particulate components of the tea. Catechin content was high in the retentate under 1000 Kpa pressures in all types of nitration process as compared to the original content in the fresh green tea leaves. Alkali and enzyme treatments of the precipitate for maximum recovery of catechins that developed on chilling after filtration improved the solubility of the extract. A partial reduction in the pectin content in the retentales with a concomitant increase in carbohydrates, protein, turbidity, catechins was noted with ullrafiltered and microfiltered extracts. Ultrafiltration caused a rejection of 24% pectin, 23.40% catechins in permeate, and 18.11% caffeine in the green tea extract.

2 illus, 1 table, 11 ref

006744   Qin Y;Shi B;Liu J (The Biochem Mater Res and Dev Cent, Jiaxing Coll, Jiaxing-314 001, Zhejiang Province, P.R. China, Email: yiminqin@hotmail.com) : Application of chitosan and alginate in treating wastewater containing heavy metal ions. Indian J chem Technol 2006, 13(5), 464-69.

Use of sodium alginate and chitosan in treating waste water containing heavy metal ions has been studied. The effect of the concentration and ratio of chitosan and sodium alginate, treatment temperature and time on the efficiency of Cu(II) ion removal was investigated. Results showed that when used in combination, sodium alginate and chitosan were effective in removing Cu(II) ions from waste water. The treatment was applied to other heavy metal ions such as cadmium, lead and silver ions, and the treatment efficiency was compared. Results showed that when used in combination, the separation of polymeric absorbents from waste water is better than when chitosan and sodium alginate are used alone.

2 illus, 5 tables, 9 ref

006743   Pradeep Kumar;Raghavendra P V K;Shri Chand (Dep of Chem Engng, Indian Inst of Technol Roorkee, Roorkee-247 667, Email: schanfch@iitr.ernet.in) : Catalytic wet air oxidation of carboxylic acid present in wastewater. J scient ind Res 2006, 65(10), 838-42.

Catalytic Wet Air Oxidation (CWAO) of acrylic acid, a representative of carboxylic acids, was carried out in a pressurized reactor at a partial pressure of air (4 kg/cm) and temperature (140-180°C) to reduce the COD of wastewater containing acrylic acid. Catalysts tested include both homogeneous (CuSO₄ and FeSO₄) and heterogeneous [Co: Bi (5:1) and Mn: Ce (1:1)] catalysts. Catalytic activity of Mn: Ce (1:1) at 5g/l was best with 86% COD reduction at 180°C and air partial pressure 4 kg/cm² in 6 h. Initial pH of the solution has strong effect on COD reduction. Reaction kinetics of wet air oxidation of acrylic acid fitted well a first order kinetics with respect to COD of acrylic acid. Catalysts activity was correlated in terms of the physical characteristics.

7 illus, 2 tables, 4 ref

006742   Ozalp A A;Umur H (Dep of Mechanical Engng, Uludag Univ, 16059, Gorukle Bursa, Turkey, Email: aozalp@uludag.edu.tr) : Optimum surface profile design and performance evaluation of inclined slider bearings. Curr Sci 2006, 90(11), 1480-91.

Aim of the present optimization study is to propose an innovative surface profile design by implementing a wavy form on the upper surface, without varying the physical limits of the complete slider-bearing structure. Differential equations governing the fluid-film mass, Reynolds and energy equations, are solved simultaneously by the iterative transfer matrix approach, which also takes into account the streamwise decrease of lubricant viscosity. Computations indicated that friction coefficient values decrease with wave amplitude in pad inclination ranges of 0-3.77°, 3.3-4.17° and 3.9-4.22° for inlet/exit pressure ratios of 1.01, 3.01 and 5.01 respectively. Wave number is determined to augment the complete pressure distribution inside the bearing and optimum wave number is evaluated as 25 for pressure management.

6 illus, 37 ref

006741   Oruc S;Celik F;Aksoy A (Dep of Civ Engng, Karadeniz Tech Univ, 61080 Trabzon, Turkey, Email: oruc@ktu.edu.tr) : Performance of cement modified dense graded cold mix asphalt and establishing mathematical model. Indian J Engng Mater Sci 2006, 13(6), 512-9.

Cold-mix asphalts have several advantages regarding economical, ecological and logistical aspects over hot-mix asphalt. But, cold-mix asphalts have poor performance and are deteriorated in case of additional external water entrance before mixture curing is completed. The study has been focused on to solve these problems and present an alternative to hot mixtures. Cold-mix asphalt specimens with dense graded aggregate were prepared according to Marshall method for emulsified asphalt-aggregate cold mixture design. Portland cement has been substituted for mineral filler in an increased percent, from 0% to 6%. Cold-mix asphalt specimens have been prepared with 4.2%, 5.2%) and 6.2% of residual asphalt contents. Indirect tensile test, static and repeated load asphalt creep tests, and water damage test have been performed on the specimens. In addition to these tests, the moisture losses of specimens that took place in time are also measured. Based on the experimental work, it has been concluded that dense graded cement modified emulsion mixtures are of great performance compared to hot mixtures with the same aggregate grading and bitumen content. A mathematical model has also been developed for determining the resilient modulus of cold-mix asphalt.

14 illus, 5 tables, 19 ref

006740   Narasimhan T N (Mater Sci and Engng Dep Envir Sci Policy and Mgmt, Univ of Calif at Berkeley, 210 Hearst Memorial Mining Building, Berkeley, Ca 94720-1760, USA, Email: tnnarasimhan@lbl.gov) : Coupled equations for transient water flow, heat flow, and deformation in hydrogeological systems. J Earth Syst Sci 2006, 115(2), 219-28.

Hydrogeological systems are earth systems influenced by water. Their behaviours are governed by interacting processes, including flow of fluids, deformation of porous materials, chemical reactions, and transport of matter and energy. Here, coupling among three of these processes is considered: flow of water, heat, and deformation, each of which is represented by a diffusion-type of partial differential equation. One side of the diffusion-type equation relates to motion of matter or energy, while the other relates to temporal changes of state variables at a given location. The coupling arises from processes that govern motion as well as those that relate to change of state. In the work, attention is devoted to coupling arising from changes in state. Partial derivatives of equations of state constitute the capacitance terms of diffusion-type equations. Of the many partial derivatives that are mathematically possible in physical systems characterized by several variables, only a few are physically significant. Because the state variables are related to each other through an equation of state, the partial derivatives must collectively satisfy a closure criterion. This framework offers a systematic way of developing the coupled set of equations that govern hydrogeological systems involving the flow of water, heat, and deformation. Such systems are described in terms of four variables, and the associated partial derivatives. The physical import of these derivatives are discussed, followed by a description of partial derivatives that are of practical interest. These partial derivatives are then used as the basis to develop a set of coupled equations. A brief discussion has been presented on coupled equations from a perspective of energy optimization.

1 table, 6 ref

006739   Narang B S;Sushil Kumar;Kumar R (Electl Engng Dep, Bhilai Inst of Technol, Bhilai House, Durg-490 001, Email: nrgbs@sancharnet.in) : Excitation control for synchronous machines by using Lyapunov design concept. Appl Sci Period 2005, 7(4), 220-6.

Excitation controller for synchronous machines has been presented. The control law is derived using the control Lyapunov function concept and an equilibrium tracking mechanism, resulting in a dynamic state feedback controller. Both damping improvement and the enlargement of the stability region are achieved, and the knowledge of the operating point is not required. Simulation results for a case study are presented showing the significant improvement obtained both in transient and dynamic performance.

3 illus, 10 ref

006738   Mathew M;Narayana B (Dep of Stud in Chem, Mangalore Univ, Mangalagangotri-574 199, Email: nbadiadka@yahoo.co.uk) : An easy spectrophotometric determination of selenium using azure B as a chromogenic reagent. Indian J chem Technol 2006, 13(5), 455-8.

Simple, rapid and sensitive spectrophotometric method has been developed for the determination of trace amounts of selenium in water samples, soil, plant materials and human hair. The proposed method is based on the reaction of selenium with potassium iodide in acidic medium to liberate iodine. The liberated iodine bleaches the violet colour of azure B, which is measured at 644 nm. This decrease in absorbance is directly proportional to selenium concentration. Beer's Law was obeyed in the range 2.0-10.0 μgmL^-1 of selenium. The molar absorptivity, Sandell,s sensitivity, quantitation limit and detection limit of the method were found to be 0.9473 x 10⁵ L mol^-1 cm^-1, 8.33 x 10⁴ μg cm^-2. 0.070 μgmL^-1 and 0.023 μgmL^-1, respectively. The proposed method has been successfully applied to the determination of selenium in various samples.

1 i, 2 t, 35 r, 1 Sch

006737   Mahapatra S S;Patnaik A (Dep of Mechanical Engng, Natn Inst of Technol, Rourkela-769 008, Email: mahapatrass2003@yahoo.com) : Optimization of wire electrical discharge machining (WEDM) process parameters using genetic algorithm. Indian J Engng Mater Sci 2006, 13(6), 494-502.

Wire electrical discharge machining (WEDM) is a special form of iraditional electrical discharge machining in which the electrode is a continuously moving conducting wire. The mechanism of metal removal in wire electrical discharge machining involves the complex erosion effect from electric sparks generated by a pulsating direct current power supply. The sparks generated between two closely spaced electrodes are immersed in dielectric liquid. However, dimensional accuracy and surface finish largely depend on process parameters such as discharge current, pulse duration, pulse frequency, wire speed, wire tension and dielectric flow rate. An experimental study has been carried out on a Robofil 100 WEDM machine to identify various significant control factors and their interactions that affect the machining performance such as metal removal rate (MRR) and surface finish (SF) based on Taguchi method. The relationship between control factors and responses like MRR and SF are established by means of non-linear regression analysis resulting in a valid mathematical model. Finally, genetic algorithm, a popular evolutionary approach, is used to optimize the wire electrical discharge machining process with multiple objectives. The study demonstrates that the WEDM process parameters can be adjusted to achieve better metal removal rate and surface finish simultaneously.

8 illus, 7 tables, 12 ref

006736   Kumaresan R;Viruthagiri T (Dep of Chem Engng, Mohamed Sathak Engng Coll, Kilakarai-623 806, Email: kumariisc@yahoo.co.in) : Simultaneous heat and mass transfer studies in drying ammonium chloride in a batch-fluidized bed dryer. Indian J chem Technol 2006, 13(5), 440-7.

Simultaneous heat and mass transfer occurs during drying. Fluidized bed drier, unlike other types of dryers is more sensitive to the variation of moisture content of the material being dried. Ammonium chloride is used. Heat and mass transfer studies were carried out using the experimental set up which consists of a well-insulated glass fluidized column with calming section and a fluidized section of height 435 mm and diameter 55 mm. Experiments were carried out with the variables- (i) size of ammonium chloride particles from 495 to 912 microns, (ii) inlet air velocity from 1.136 to 1.391 m/s, (iii) temperature of inlet air to the fluidized bed dryer from 60 to 75°C, (iv) initial moisture content of ammonium chloride to the fluidized bed dryer from 0.04 to 0.06 kg of water/kg of bone dry ammonium chloride, (v) bed hold of 0.090 to 0.130 kg. Humidity of the inlet air to the fluidized bed is determined by measuring the dry and wet bulb temperatures and using the psychrometric chart. Microsoft Excel spreadsheets are used for the calculations. A correlation between Nusselt number and Reynolds number was developed using the least square method. A simplified unsteady state mass transfer equation was developed to determine the diffusion coefficient.

1 illus, 2 tables, 7 ref

006735   Khare K;Singh R P;Khare N (Dep of Electron and Commun Engng, MANIT, Bhopal, Email: kavita_khare1@yahoo.co.in) : Comparison of pipelined IEEE-754 standard floating point multiplier with unpipelined multiplier. J scient ind Res 2006, 65(11), 900-4.

IEEE-754 standard floating point multiplier that provides highly precise computations to achieve high throughput and low area on the IC have been improved by insertion of pipelining technique. Floating point multiplier-using pipelining has been simulated, analyzed and its superiority over traditional designs is discussed. To achieve pipelining, one must subdivide the input process into sequence subtasks, each of which can be executed by specialized hardware stage that operates concurrently with other stages in the pipeline without the need of extra computing units. Detailed synthesis and simulation report operated upon Xilinx ISE 5.2i and Modelsim software is given. Hardware design is implemented on Virtex FPGA chips.

5 illus, 2 tables, 11 ref

006734   Keshavarz M H;Tehrani M K;Pouretedal H R; Semnani A (Dep of Chem, Malek-ashtar Univ of Technol, Shahin-shahr P.O. Box 83145/115, Islamic Republic of Iran, Email: mhkeshavarz@mut.es.ac.ir) : New pathway for quick estimation of gas phase heat of formation of non-aromatic energetic compounds. Indian J Engng Mater Sci 2006, 13(6), 542-8.

New theoretical approach is presented for calculation of gas phase heals of formation of non-aromatic energetic compounds. It is based on elemental composition and various functional groups of C_aH_bN_cO_d non-aromatic energetic compounds. Gas phase heats of formation for 85 non-aromatic energetic compounds are compared with experimental data as well as semi-empirical quantum mechanical PM3 prediction. Root mean square (rms) of deviation for some of them, where experimental data are available, shows 5.1 and 6.7 keal/mol for new and semi-empirical quantum mechanical PM3 methods respectively.

1 table, 27 ref

006733   Kar K K;Sharma S D;Behera S K;Prashant Kumar (Advd Nano Engng Mater Lab Dep of Mechanical Engng, Indian Inst of Technol, Kanpur-208 016, Email: kamalkk@iitk.ac.in) : Development of rubber pressure moulding technique using polybutadiene rubber to fabricate fibre reinforced plastic components based on glass fibre and epoxy resin. Curr Sci 2006, 90(11), 1493-9.

Rubber pressure moulding technique is developed to prepare fibre reinforced plastic components (FRP) using glass fibre and epoxy resin. The technique is based on the matching die set, where the die is made of hard metal like steel and the punch from flexible rubber-like materials. The use of flexible rubber punch helps to intensify and uniformly redistribute pressure (both operating pressure and developed hydrostatic pressure due to the flexible rubber punch) on the surface of the product. A split steel die and rubber punch were designed and fabricated to prepare the FRP components. The same split die was also used to cast the rubber punch. Polybutadiene rubber was used to prepare rubber punch in this investigation. Burn test, coin test, scanning electron microscopy and mechanical tests like interlaminar fracture toughness, interlaminar shear test, tension test, etc. were carried out to know the fibre content, void content, presence of delamination, bonding between fibre and resin, microstructure and mechanical properties of the composite materials. These properties were also compared with FRP components made by the conventional technique to evaluate their performances in structural applications.

7 illus, 3 tables, 13 ref

006732   Harapanahalli R;Lokeshappa B;Manjunath N T (NO, KLE Society's Coll of Engng and Technol, Udyambag, Belgaum-590 008) : Wastewater management for textile industries in common effluent treatment plant. Indian J envir Prot 2006, 26(5), 429-32.

Water bearing industries, like textile industries, tanneries, pulp and paper, etc., generate large quantity of wastewater with characteristics that affect the environment and receiving water bodies if discharged into them without adequate treatment. Even after treating the effluent, major problems faced by the treatment units include high total dissolved solids, chloride, sulphate and disposal of sludge, which are well above the permissible limits in context to pollution control board's regulations. Objectives and methodologies were defined to take the stock of existing waste management plans and to suggest the remedies there of. The high TDS concentration and presence of various metals in industrial effluent, makes the treatment of the wastewater specific and costly. However, it is an obligation of any industry to treat the waste and discharge the same after meeting the disposal standards. The small-scale industries (SSI) is unique feature of Indian industrial development in general and at Tiruppur in particular for testile industry. The chemicals used in treatment of these effluents increase the total dissolved solids in the treated effluent in turn increases the quantum of sludge generated. Highlights the wastewater management in common effluent treatment plant.

3 illus, 1 table, 5 ref

006731   Gaitonde V N;Karnik S R;Achyutha B T; Siddeswarappa B (Dep of Industrial & Production Engng, B V B Coll of Engng & Technol, Hubli-580 031) : Taguchi approach with multiple performance characteristics for burr size minimization in drilling. J scient ind Res 2006, 65(12), 977-81.

Application of Taguchi optimization method for simultaneous minimization of burr height and burr thickness influenced by cutting conditions and drill geometry has been presented. The approach of Taguchi design for multi-objective optimization problem is based on the introduction of a new concept of fitness function for each trial of orthogonal array. The fitness function is derived through mapping the objective functions of the drill optimization problem. In present work. optimal values of cutting speed, feed, point angle and lip clearance angle are determined for a selected drill diam to minimize burr height and burr thickness during drilling of AISI 316L stainless steel workpieces. The effectiveness of proposed method is demonstrated through simulation results and experimental verifications.

2 illus, 6 tables, 24 ref

006730   Gaitonde V N;Karnik S R;Achyutha B T; Siddeswarappa B (Dep of Industrial & Production Engng, B V B Coll of Engng & Technol, Hubli-580 031, Email: gaitondevn@yahoo.co.in) : Multi-response optimization in drilling using Taguchi's quality loss function. Indian J Engng Mater Sci 2006, 13(6), 484-8.

Exit burr formation in drilling is influenced by cutting conditions and drill geometry. Presents the application of Taguchi's analysis for simultaneous minimization of burr height and burr thickness. The approach of Taguchi design for multi-response optimization problem, is based on loss function of the quality characteristics. Optimal values of cutting speed, feed, point angle and lip clearance angle are determined to minimize bun-height and burr thickness during drilling has been investigated. The potential of the proposed methodology is demonstrated through a case study of drilling process using AISI 316L stainless steel workpieces.

1 illus, 6 tables, 16 ref

006729   Duhan M;Singh P (Dep of ECE, GJU, Hisar) : Comparative broughtouts with wavelength division multiplexing network for different sources. Ultra Scient phys Sci 2006, 18(1), 39-42.

Optical wavelengths division multiplexing offers several unique features that can be exploited to advantage in optical networks.

5 illus, 8 ref

006728   Debsarkar A;Mukherjee S N;Datta S (Envir Engng Div Civ Engng Div, Jadavpur Univ, Kolkata-700 032) : Performance of a laboratory-scale sequencing batch reactor (SBR) for combined COD and nitrogen removal. Indian J envir Prot 2006, 26(5), 411-18.

A laboratory-scale sequencing batch reactor (SBR) was operated under 2 different combinations of aerobic-anoxic sequence, namely (4+4) and (5+3) hr with input SCOD level varying from (1000±150) to (2500±100) mg/L and initial ammonia nitrogen from (40±5) to (180±5) mg/L as N. In case of (4+4) and (5+3) operating cycles, both from the view point of SCOD and NH₄⁺-N removal optimum values of initial SCOD/NH₄⁺-N ratio were found to be 28.31 and 24.83, respectively. The performance of the reactor was investigated under optimum initial SCOD/NH₄⁺-N ratio, a reduction of 90-95% and 100% of SCOD and NH₄⁺-N, respectively were achieved at the end of total batch reaction period. Denitrification efficiency in the tune of 78.06% and 62.07% as (NO₃^--N) reduction was achieved at the end of settle period for (4+4) and (5+3) operating cycles, respectivley.

7 illus, 10 ref

006727   Chen C K;Lo S L (NO, Grad Inst of Envir Engng Natn Taiwan Univ, 71, Chou-Shan Rd., Taipei, 106, Taiwan) : Treating restaurant wastewater using a combined activated sludge contact aeration system. J envir Biol 2006, 27(2), 167-73.

Combined activated sludge/contact aeration (AS/CA) system proposed herein involves both suspended and attached microorganisms. In an experiment over 7 days, and at 8 hr hydraulic retention time (HRT), the AS/CA system was able to treat restaurant wastewater of fluctuating quantity and quality, and reduce the standard deviations of COD and BOD5 from 115.8 and 158 to 40.5 and 8.8 mg/l, respectively. In a twenty-four hour experiment, the standard deviation of COD fell from 188.9 to 23.8 mg/l, showing a strong tolerance of environmental changes. In an analysis of composite samples collected over 1 day, the AS/CA effluent had 57.8 mg/l COD (84% removal rate), 21 mg/l BOD₅ (87% removal rate), 12 mg/l SS (86% removal rate), 6 mg/l oil and grease (0 and G) (90% removal rate), and a true color of 1 (80% removal rate). Denaturing Gradient Gel Electrophoresis (DGGE) analysis was performed on sludge samples taken from three treatment systems: the activated sludge system the contact aeration system and the AS/CA system for comparison. The results showed that the AS/CA system contained higher microbe quantity and diversity.

8 illus, 3 tables, 6 ref

006726   Chauhan M S;Dikshit A K (Cent for Envir Sci and Engng, Indian Inst of Technol, Powai, Mumbai-400 076) : Treatment options for decolourisation of distillery wastewater. Indian J envir Prot 2006, 26(5), 400-10.

Alcohol is produced in India by the fermentation of molasses, which the mother liquor left after the sugar production. Spent wash, the effluent from the fermentation process in distilleries, is characterized by high COD and dark brown colour. Almost all distilleries treat their spent wash by anaerobic digestion to reduce COD and to produce methane for energy recovery. The colour of the anaerobically treated distillery effluent is still high enough to severely affect the receiving stream, the groundwater or the land. To bring the colour down, tertiary treatment in the form of physico-chemical methods, such as coagulation, membrane filtration, ozonation and/or biological methods by different microorganisms is required. Discusses various technological options available for decolourisation of distillery wastewater. It has been found that although many physico-chemical and biological treatment options are available in literature of colour removal from post methanated effluent of distilleries, most of them could not find their application at the industry level for their technical limitation or cost effectiveness. Hence, further research is needed to evolve cost effective and feasible technologies for industrial applications.

1 illus, 4 tables, 31 ref

006725   Chandra Mouli K V V;Subbaiah K V;Acharyulu S G (Dep of Industrial Production Engng, Coll of Engng, GITAM, Visakhapatnam-530 045, Email: acharyulusg@rediffmail.com) : Optimal production planning under resource constraints. J scient ind Res 2006, 65(12), 966-69.

Production planning is meant to arrive at the framework of manufacturing operations during the period planned. The paper addresses the solution for finding an optimal production planning to minimize the total cost under the resource constraints taking overtime and subcontracting costs. A mathematical model is formulated and Genetic algorithms are implemented in constrained optimization to arrive an optimal solution.

1 illus, 6 tables, 11 ref

006724   Bishnoi N R;Rajender Kumar;Kamlesh (Envir Sci and Engng Dep, Guru Jambheshwar Univ, Hisar-125 001) : Characterization and anaerobic digestion of paper and pulp mill effluent - a lab scale study. Indian J envir Prot 2006, 26(5), 458-62.

Pulp and paper mill generates large volumes of highly heterogeneous wastewater containing compounds from wood or other raw material process chemical as well as compounds formed during processing. Characteristically, the wastewater would consist less toxic and easily amenable matter for the microorganism. Anaerobic treatment is an attractive treatment alternative for pulp and paper mill effluents and the organic load in the effluent could be recovered partially as methane, a valuable energy source. Experiments were conducted for the anaerobic biodegradation of the organic fraction of pulp and paper mill wastewater in a laboratory scale biodigester (5 L capacity) operated in semi-continuous mode in BOD incubator at 37°C and 25 day hydraulic retention time is reported. A satisfactory treatment was found by anaerobic digestion of pulp and paper mill wastewater. Overall percentage removal of COD was 69.45% and gas production was ranged from 110 to 160 mL/L/d. Anaerobic process is affected by different prarameters as pH, TVFA, COD and gas protection. Analysis of effluent for pH, total volatile fatty acids (TVFA), chemical oxygen demand (COD) and gas production were performed regularly to access digester performance during start-up and on stabilization of effluent.

4 illus, 1 table, 10 ref

006723   Azadeh M A;Keramati A;Mohammadfam I; Jamshidnedjad B (Dep of Industrial Engineering. Fac of Engng, Univ of Tehran, Tehran, Iran, Email: ali@azadeh.com) : Enhancing the availability and reliability of power plants through macroergonomics approach. J scient ind Res 2006, 65(11), 873-8.

Integrated macroergonomics model for operation and maintenance of power plants has been described. Statistical tests on questionnaire survey data shows the importance of total human factors on job pressure. An integrated approach based on interview methods, questionnaires, information flow analysis and anthropometric and environmental assessment is discussed. The integrated approach provides detailed knowledge about ergonomics, management and safety conditions of power plants. High lights the employment of a total system approach based on integration of the traditional human factors engineering and macroergonomics considerations. The approach of the study is applied to an advanced thermal power plant.

1 illus, 4 tables, 20 ref

006722   Ash B;Satapathy D;Mukherjee P S;Nanda B; Gumaste J L;Mishra B K (NO, Regional Res Lab, Bhubaneswar-751 013, Email: psmukherjee@rrlbhu.res.in) : Characterization and application of activated carbon prepared from waste coir pith. J scient ind Res 2006, 65(12), 1008-12.

Activated carbon (AC) has been prepared from raw coconut pith and coconut pith impregnated with H₃PO₄ and NaOH solutions separately. AC was characterized with SEM, particle size analyzer and proximate analyzer. Adsorption studies were carried out using UV and atomic absorption spectrophotometer to find its effectiveness. AC obtained from coconut pith treated with phosphoric acid was found comparable to the commercial grade samples.

3 illus, 2 tables, 16 ref

006721   Arora S;Dhaliwal S S;Kukreja V K (Dep of Math, Sant Longowal Inst of Engng and Technol, Longowal-148 106, Email: vkkukreja@lycos.com) : Modelling of the displacement washing of pulp fibre bed. Indian J chem Technol 2006, 13(5), 433-9.

Mechanism of the displacement washing of the bed of pulp fibres is mathematically modelled using a single parameter namely, Peclet number. The bulk fluid concentration is assumed to be the function of washing period and position in the bed. The effect of Peclet number on exit solute concentration is shown using the breakthrough curves. A non-linear adsorption isotherm (Langmuir) is used to describe the relationship between bulk fluid concentration and the concentration of solute accumulated on the particle surface. The validity of the model is shown using the literature data. A comparison of washing behaviour of pulp fibres and static bed of glass beads is also presented.

6 illus, 2 tables, 12 ref

005796   Yogendra Prasad (Natn Hydroelectric Pwr Corporation Ltd, , Sector 33, Faridabad, Haryana) : Impact of freaquency excursions. Wat Energy int 2006, 63(3), 32-7.

Expectations for quality power are great and are likely to remain so in future as well. Stability of the power system avoiding frequency excursions is essential for smooth operation and for reduction in various technical and commercial losses. Frequency excursions are not desirable as these have detrimental effects on efficiency and life of generating equipments. At times, these may turn out to be acutely hazardous leading to collapse of the whole system. Persistent efforts have been made to explore the new possibilities to keep the grid freaquency under check. Appropriate Hydro: Thermal mix and concept of energy storage can strengthen the system by instantly compensating for the generation/load imbalance and stabilizing the system. Proper power management and discipline adequately contributes towards accomplishign stability in the grid. Hydro and pumped storage schemes have vital role to play in maintaining a healthy power syste.

3 illus, 1 table

005795   Yildirim S;Eski I (Dep of Mechancial Engng Fac of Engng, Erciyes Univ, Kayseri, 38039, Turkey, Email: sahiny@erciyes.edu.tr) : Design of robust model based neural controller for controlling vibration of active suspension system. J scient ind Res 2006, 65(8), 646-54.

New robust model based neural controller (NC) for active suspension system (ASS)'s vibrations via feedback control approach. The proposed control system consists of a NC, a robust feedback controller, a third-order linear reference model and dynamics of ASS. The simulation examples with various standard input signals arc included to demonstrate the effectiveness of the proposed control method and show significant improvement over the existing PID controller method. The robustness of the proposed NC is also analyzed with white noise disturbances on the suspension system. It is shown that the control system is robustly stable for all road disturbances.

9 illus, 6 ref