001698   Babanejhad A;Hashemi M;Rahmatallahpur Y;Nozad S A (NO, Material Research School, Bonab, Iran, Email: ababanejhad@bnrc.ir) : Effect of lactic acid on nucleation morphology and surface roughness of electroless Ni-P deposition in nanoscale. Bull Mater Sci 2012, 35(4), 561-6.

The present work aims to study effect of lactic acid concentration as complexing agent on surface roughness and nucleation morphology of electroless N-P deposition. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) have been used to study nucleation morphology and surface roughness of deposition. Deposition process started at some initial priority growing centres independently distributed on the substrate. We found that the morphology and surface roughness of deposition strongly depends on the complexing agent concentration. Morphology of initial deposited centres with no concentration of lactic acid was in coniform structure. By increasing the complexing agent concentration, the structure of initial growing centres changed from coniform to nodular shape and the surface roughness of depositions decreased.

5 illus, 2 tables, 10 ref

001697   Ashfaq A;Maheshwari S (Faculty of Engineering & Technology, AMU, Aligarh, Email: ahmad_ashfaq76@yahoo.com) : Potential of hydropower and its utilization for the conservation of environment. Ecol Envir Conserv 2011, 17(3), 567-70.

As energy becomes the current catchphrase in business, industry, and society, energy alternatives are becoming increasingly popular. The inherent technical, economic and environmental benefit of hydroelectric power makes it an important contributor to the future world energy mix, particularly in the developing countries. These countries have a great and ever-intensifying need for power and water supplies and they also have greatest remaining hydro potential. Hydroelectricity exists as one option to meet the growing demand for energy and is discussed in this paper.

4 tables, 5 ref

001696   Ashfaq A;Khatoon A (Faculty of Engineering & Technology, Aligarh Muslim Univ, A.M.U., Aligarh, Email: ahmad_ashfaq76@yahoo.com) : Utilization of wind power as a renewable source of energy for conservation of environment. Ecol Envir Conserv 2011, 17(3), 531-4.

Electricity shortages are common these days and a significant part of the population has no access to electricity at all in India. The best solution lies in the use of renewable sources of energy. Wind power is the world fastest growing energy resources, at the rate of 27% per year. It is gaining popularity due to various environmental benefits like reduction in emission of CO₂, it is environment friendly, emits no pollutant or waste heat and needs no cooling water, and it is one of the renewable means of electricity generation. The paper discusses the present scenario of wind energy in India and its future. It deals with the technical details and principles involved in the extraction of energy from wind.

8 ref

001695   Anjum M I (NO, Ghousia College of Engineering, Ramanagaram, Karnataka, Email: anjum61@rediffmail.com) : Adopting appropriate gradation in design of bituminous concrete mixes at constant combined index determined corresponding to actual aggregate size. J Constr Engng Technol Mgmt 2013, 3(2), 1-4.

MoRTH in India specifies gradation tables for preparing bituminous mixes with desirable range of aggregates passing for each aggregate fraction. Conventionally, the mix is designed by adopting midpoint of the specified range of aggregates passing, anticipating a satisfactory mix and avoid several trials required to arrive at the best gradation within the specified range. In this approach, the aggregate shape factors expressed as combined index being the sum of flaky and elongation indices of aggregates in the mix, are determined using conventional instruments. The limitation is that the slot sizes available on instruments are not the same as the sieve sizes in gradation tables. In spite of this, the shape factors determined are still assumed to be approximately the same as those for the actual aggregates sizes, example available is 25-20 mm while size required is 26.5-19 mm. As such, an attempt was made to determine the shape factors for the actual aggregates sizes and ascertain if the midpoint gradation approach is still valid. Bituminous concrete mixes were prepared corresponding to the midpoint (MG) as well as the lower (LG) and higher (HG) limits besides the mid points of lower - mid point (LMG) and higher - mid point (HMG) gradations by using same aggregates. All the other materials and their properties were maintained uniform. The Marshall Test properties of bituminous concrete mix-grade 1, at these five gradations were compared. It was noted that the conventional midpoint gradation does not produce the most satisfactory mix.

7 illus, 3 tables, 7 ref

000501   Zamani M (Technology and Engineering Dep, Yasouj Univ, Daneshjoo Avenue, Moallen Square, Yasouj, Iran) : Investigation of hydraulic conductivity determination for anisotropic soils. Oriental J Chem 2012, 28(1), 491-7.

One of the important parameters for determining the discharge through the subsurface system in groundwater engineering is hydraulic conductivity coefficient. This parameters the factor of oil skeleton and fluid properties. The horizontal and vertical components of saturated hydraulic conductivity coefficient can be obtained from the laboratory and field testing methods. Those are usually constant and variable head tests. In this research the three-dimensional ellipsoid of hydraulic conductivity coefficients is obtained. Using the hydraulic conductivity ellipsoid it is possible of obtain the permeability of soil in any direction. The above model has the effective application for calculation of one, two and three-dimensional fluid flow in the anisotropic porous media. The accuracy of thehydraulic conductivity obtained by the model can be checked by laboratory tests. The model is applied for the calculation of infiltration from the natural or man-made surface channels, also exfilitration from the subsurface water resources.

6 illus, 7 ref

000500   Yazici S;Arel H S (Civil Engineering Dep, Engineering Faculty, 35100 Izmir, Turkey, Email: semsiyazici@gmail.com) : Effects of fly ash fineness on the mechanical properties of concrete. Sadhana 2012, 37(3), 389-403.

Study reviews the effects of fly ash fineness on the comp-ressive and splitting tensile strength of the concretes. A fly ash of lignite origin with Blaine fineness of 2351 cm²/g was ground in a ball mill. As a consequence of the grinding process, fly ashes with fineness of 3849 cm²/g and 5239 cm²g were obtained. Fly ashes with three different fineness were used instead of cement of 0%, 5%, 10%, and 15% and ten different types of concrete mixture were produced. In the concrete mixtures, the dosage of binder and water/cement ratio were fixed at 350 kg/m³ and 0.50, respectively. Slump values for the concretes were adjusted to be 100 ± 20 mm. Cubic samples were cast with edges of 100 mm. The specimens were cured in water at 20°C. At the end of curing process, compressive and splitting tensile strengths of the concrete samples were determined at 7, 28, 56, 90, 120 and 180 days. It was observed that compressive and splitting tensile strength of the concretes was affected by fineness of fly ash in short-and long-terms. It was found that compressive and tensile strength of the concretes increased as fly ash fineness increased. It was concluded that Blaine fineness value should be above 3849 cm²/g fineness of fly ash to have positive impact on mechanical properties of concrete. The effects of fly ash fineness on the compressive and splitting tensile strength of the concretes were remarkably seen in the fly ash with FAC code with fineness of 5235 cm²/g.

8 tables, 12 illus, 12 ref

000499   Venkatraman B;Menaka M (NO, Indira Gandhi Centre for Atomic Research, Kalpakkam-603 102, Email: bvenkat@igcar.gov.in ) : Non-destructive evaluation of welds - an overview. Indian Weld J 2011, 44(3), 71-80.

13 illus, 4 ref

000498   Vadiraj A;Kamaraj M;Sreenivasan V S (Advanced Engineering Dep, Ashok Leyland Technical Centre, Vellivoyalchvadi, Chennai-600 103, Email: aravind.vadiraj@ashokleyland.com ) : Effect of solid lubricants on friction and wear behaviour of alloyed gray cast iron. Sadhana 2012, 37(5), 569-77.

Friction and wear behaviour of MoS₂, boric acid, graphite and TiO₂ at four different sliding speeds (1.0,1.5,2.0,2.5 m/s) has been compared with dry sliding condition. MoS2 and graphite show 30 to 50% reduction in mass loss compared to other lubricants at all sliding speeds. Friction coefficient reduces with increase in sliding speeds for all the conditions. Friction coefficient of dry as well as lubricant coated samples varies from 0.2 to 0.55 with MoS₂ showing the lowest value (0.2). Boric acid and TiO₂ coated samples show high friction coefficients at higher sliding speeds due to poor lubricity and adherence. This could also be due to sliding resistance offered by lubricant coated samples with predominant asperities interaction. MoS₂ and graphite coated samples also generated lowest frictional temperature compared to other conditions.

6 illus, 21 ref

000497   Turkel S;Aksin E (Civil Engineering Dep, Dokuz Eylul Univ, Izmir, 35160, Turkey, Email: selcuk.turkel@deu.edu.tr) : A comparative study on the use of fly ash and phosphogypsum in the brick production. Sadhana 2012, 37(5), 595-607.

Over 15 million tons of fly ash (FA) and 3 million tons of phospho-gypsum (PG) are produced in Turkey every year. The utilization of these industrial by-product materials is important in terms of environmental and economical issues are concerned. The main purpose of this study is to evaluate the technical possibilities of incorporating FA and PG in production of building blocks. Various mixtures were prepared by incorporating these industrial wastes by replacing clay with seven different weight proportions (0%, 5%, 10%, 15%, 20%, 25% and 30%). All specimens were fired at 1000°C peak temperature. The physical and mechanical properties of all specimens such as; unit weight, compressive strength, flexural strength, dimensional stability and water absorption values were recorded. The effect of PG incorporation on the properties of samples seems to be more dominant than the effect of FA incorporation. The test results showed that; PG incorporation increased the unit weight and mechanical strength values while lowering the water absorption values. Utilization of these wastes additives is not only for conservation of clay resources, but also an alternative solution to a difficult and expensive waste disposal problems.

13 illus, 2 tables, 30 ref

000496   Thangarasu A;Murugan N;Dinaharan I;Vijay S J (Mechanical Engineering Dep, Sri Ramakrishna Institute of Technology, Coimbatore-641 010, Email: dinaweld2009@gmail.com) : Microstructure and microhardness of AA1050/TiC surface composite fabricated using friction stir processing. Sadhana 2012, 37(5), 579-86.

Friction stir processing (FSP) has been developed by several researchers to produce an upper surface modification of metallic materials. The fabrication of TiC particulate (~2 μm) reinforced aluminum matrix composite (AMC) using FSP is studied in this paper. The measured content of TiC powders were compacted into a groove of 0.5 mm x 5.5 mm. A single pass FSP was carried out using a tool rotational speed of 1600 rpm, processing speed of 60 mm/min and axial force of 10 kN. A tool made of HCHCr steel, oil hardened to 62 HRC, having a cylindrical profile was used in this study. The microstructure and microhardness of the fabricated AMC were analysed. Scanning Electron Microscope (SEM) micrographs revealed a uniform distribution of TiC particles which were well-bonded to the matrix alloy. The hardness of the AMC increased by 45% higher than that of the matrix alloy.

1 table, 8 illus, 18 ref

000495   Suneesh P U;Jayaprakashm R;Arunkumar T;Sanjay Kumar (Research and Development Centre, Bharathiyar Univ, Coimbatore, Tamil Nadu, Email: jprakash_jpr@rediffmail.com) : Experimental studies on V-type solar still with flat wick absorber. J Envir Res Dev 2012, 6(4), 1083-6.

Solar still distillation is a natural phenomenon on earth. Solar energy heats water in the seas and lakes, evaporating and condensing it as clouds to return to earth as rainwater. Basin type solar still systems replicate this natural phenomenon on small scale and are the most common method for solar water distillation. An experimental investigation on V-typc wick solar still with flat absorber is presented in this paper. A two segment still of 1.5 m² is constructed. The performance of solar still was experimentally tested on typical summer days. Experimental investigations on productivity, efficiency, internal heat transfer are analyzed. It is found that the role of the absorber wick kept has a greater effect in distillate output. A significant aspect of the still observed from the study is low mass flow rate and minimal overflow of saline water as compared to the conventional wick type stills. The fabrication is easy and economical and can be promoted for the rural people.

^ssc4 illus, 7 ref

000494   Suneel Kumar;Vijayalakshmi M R;Ravidutta B V; Sreedhar S (NO, Gas Turbine Research Establishment, GTRE, DRDO, Bangalore, Email: suneelpandit@gtre.drdo.in) : Role of metrology during aero engine component testing. Mfg Technol Today 2012, 11(3), 19-22.

Metrology plays a vital role in any field of research and development. The precise and accurate measurement of the measured entity is crucial during the testing of hardware of an aero engine. Aero engine components go under rigorous testing of safety and life related tests before being certified for the flight application. So accurate tests results will only be possible if the measurements are accurate. Thus, it becomes extremely essential for the measurement system to support the accurate results. The current paper discusses about the metrology aspects involved during the life related cyclic tests of aero engine components like shafts. In this paper a case study explains about the dimensional metrology involved during the torsional fatigue testing on the aero engine components. Paper gives a brief account about the certain measurements like twist and a way of measuring it. Measurement involves use of coordinate measuring machine and conventional instruments as well. It also discusses about the importance of dimensional metrology involved during the testing.

4 illus, 2 tables, 6 ref

000493   Sundaresan S (NO, M. S. Univ, Baroda) : Welding research in Indian universities. Indian Weld J 2011, 44(3), 86-90.

000492   Subbaiah K;Geetha M;Shanmugarajan B;Koteswara Rao S R (NO, Sri Sivasubramaniya Nadar College of Engineering, Chennai-603 110, Email: subbaiahk@ssn.edu.in) : Comparative evaluation of tungsten inert gas and laser beam welding of AA5083-H321. Sadhana 2012, 37(5), 587-93.

In this study, the bead-on-plate welds were made on AA5083-H321 alloy plates using both tungsten inert gas (TIG) welding and laser beam (LB) welding processes to study the enhancement of mechanical properties such as weld yield strength and hardness. The low heat input of laser beam welding effectively reduced the size of the fusion zone and heat affected zone compared to tungsten inert gas welding process. High speed LB welding and fast heating and cooling of LB welding process hinders grain growth compared to TIG welding process. The effect of vapourization of volatile alloying elements is also considered. It seems that magnesium evaporation is relatively less in LB welding compared to TIG welding. Tensile testing of the welded joints revealed that LB welding results in superior mechanical properties. It is concluded that LB welding process is more suitable to join AA5083-H321.

5 illus, 2 tables, 14 ref

000491   Smallbone;Chris (NO, Welding Technology Institute of Australia, Sydney, Australia) : Welding in the world and the future. Indian Weld J 2011, 44(3), 26-37.

Since its establishment 60 years ago, the International Institute of Welding (IIW) has had numerous successes that have helped the world. With world population predicted to top 7 billion in 2011 and 9 billion by 2045, the pressures on manufacturing, infrastructure, power generation etc. not to mention basic needs such as food, water, shelter and education, will become enormous common challenges. In 2006, the IIW introduced a major project entitled "To Improve the Global Quality of Life Through Optimum Use of Welding Technology". Many of the initiatives implemented will be of benefit to many countries and regions, particularly with such significant global growth taking place throughout the world. It is estimated that during this next decade, many trillions of US dollars will be spent on infrastructure projects in the energy and processing industry, in this truly global world. Besides the normal fabrication, construction and maintenance work within countries, the additional infrastructure projects will create challenges for welding technology. Such challenges include the fabrication, construction, maintenance, inspection and testing of trillions of components whilst ensuring that they are made efficiently and cost effectively, in an environmentally friendly manner and have high integrity and reliability in service. In most industrialised countries, much equipment is aging and plant life is pushed well beyond original design considerations. Much plant is now required to operate at extremely high levels of availability with very limited time available for inspection and maintenance. This is a recipe for disaster. It is predicted that in five years' time the world will see an increasing number of failures such as these, possibly resulting in death, injury, environmental damage and lost production. The subsequent economic impact will be enormous. This paper gives an overview of the work of IIW internationally, in various regions of the world and industry sectors utilizing welding, the challenges being faced, opportunities available, and probable requirements for the successful introduction and optimum use of welding technology. Successful models used in other countries, particularly for technology diffusion to industry, education and training, improving the image of welding and the use of appropriate technologies will be highlighted. Examples of how the elements of such models could be used will be given. The involvement of industry and governments across the world in conjunction with the work of IIW and its 54 member countries is critical to the success of such initiatives.

22 ref

000490   Sarkar B P (Publisher, 'Steel Tech' Journal, Kolkata, Email: sarkar.bp@gmail.com) : Demand of steel in India - evolving scenario. Indian Weld J 2011, 44(3), 51-7.

Present production of steel in India is about 65 million tones and the per capita consumption of finished steel is 47.8 kg which is much below the world average of 180 kg. The rural consumption is abysmally low at 2 to 3 kg. However, India is now at the threshold of a significant increase in steel production and demand. India is now the happening place in the eyes of the outside world. It has huge resources of raw material for iron and steelmaking, enough skilled manpower, and labour cost is low. It has the potential of becoming the steel producer at lowest cost. The sharp hike in demand for steel is arising from the larger disposable income of a large section of people, huge investments by the Govt. of India to improve the infrastructure and massive investments by both Indian and foreign companies to make India as the manufacturing hub for steel related items. If India can produce steel at lowest cost, there is huge scope for increasing exports. The crude steel production target announced in 2006 by the Govt. of India was 110 Mt by 2010 and later revised it. Experts predict that the production by 2012 will be around 100 to 120 Mt and by 2020, it will be 180 to 250 Mt. The production of special steels like Stainless Steels, high strength steels, etc. will also increase proportionately for the automobile sector, consumer goods and construction. The demand of steel is predicted to grow at the rate of 10% each year from now onwards. The present low per capita consumption of steel, the aspirations of people for higher standard of living, its raw material resources, export opportunities, etc. will make India surely the second highest steel producer in a short time which may not be comparable to China but implies significant achievement compared to the present position.

7 tables

000489   Sadeghi J;Ahangar M (NO, , Sistan and Baluchestan, Iran, Univ, Email: jsadeghi@hamoon.usb.ac.ir) : Methanol separation columns control. Oriental J Chem 2012, 28(1), 229-35.

The design, optimization and better control of refinery processes becomes possible via dynamic simulation. In this article, a methanol distillation unit consisting of three columns has been simulated in order to separate methanol from water, dissolved gasses and heavy hydrocarbons in steady and dynamic states by using Aspen Dynamic and Aspen Plus softwares. Morover, the present study investigates, using simulink/matlab software, the effect of variable changes such as methanol concentration of feed and feed flow rate on the performance of the controllers and the rate of purity of the product methanol flow and water in the bottom of the columns. This system has thermal integration property so that the condenser of the second column acts as the reboiler of the third column and these two thermal loads are considered equal in the flow sheeting equation section of the Aspen Plus software. Then, in dynamic environment, by installing level pressure controllers, the flow rate of feed and product for the three columns, the performance of the unit and the purity of the product will be controlled. The number of the stages (trays) of these three columns is high and shows that there is apparently no need to install thermal temperature controller. Whereas by installing a temperature controller for the first and second column and temperature regulation with reboiler Q (thermal load), as well as cascading control of the third column temperature by means of cascade flow controller in the bottom of this column, the results show high degree of seperation of methanol distillation product. The findings of the research also show that, with the increase of feed flow rate, the purity rate of methanol products will increase, while the purity rate of water flow will decrease. In addition, the increase of feed methanol composition is ineffective on the purity of methanol flows but it has increased the rate of water flow purity. Such a good separation, in turn, is the result of temerature controller instalation. Meanwhile, the increase and reduction of the feed stage position of the first column does not affect the purity of the three product flows.

8 illus, 5 ref

000488   Reddy K N;Narayanan N;Shashi Kumar P V; Jambagi S C (Micro Engineering & Nano Technology Dep, Technology Institute, Tumkur Road, Bangalore, Email: mnt@cmti_india.net) : Establishment of optimum number of scanning points for a scanning feature using ultra precision CMM. Mfg Technol Today 2012, 11(3), 23-6.

Coordinate measuring machine (CMM) is a measuring system with a movable probing system and capability to determine spatial coordinates on a work piece surface, that can be further analyzed to arrive at the required parameters. As geometry of feature is not ideal, the number of points, their distribution and their computation method have an effect on the results of dimension, form and position and therefore on also coordinate system. Discrete point probing uses only few points to calculate the ideal circle; the outcome of this is incorrect information on form shape. For features having functional requirement like assembly, running accuracy form is critical and true shape of the feature is required. Hence, CMMs are developed with scanning feature; which supplies the large data quantities for evaluation. The optimization of scanning parameters like number of points for a feature is one of the important parameters in the coordinate metrology. The aim of the paper is to describe the effect of number of points for scanning a feature and optimization of this scanning parameter and to adopt the optimized scanning data to the discrete point probing system.

7 illus, 3 tables, 7 ref

000487   Rawat M K;Das L G;Chattopadhyay H;Neogi S (NO, Central Mechanical Engineering Research Institute (CSIR-CMERI), Durgapur, Email: m_rawat@cmeri.res.in) : Experimental investigation on thermoelectric refrigerations system: a potential green refrigeration technology. J Envir Res Dev 2012, 6(4), 1059-65.

Conventional refrigeration systems use ChloroFluoro Carbons (CFCs) and Hydro Chlorofluorocarbons (HCFCs) as heat carrier fluids. Use of such fluids in conventional refrigeration systems has a great concern of environmental degradation and resulted in extensive research into development of novel refrigeration technologies. Thermoelectric Refrigeration (TER) has emerged as a promising refrigeration technology due to their distinct advantages. The research and development work carried out by different researchers on novel TER system is thoroughly reviewed in this paper. The present group of authors is also conducting research for development of thermoelectric refrigeration system powered by solar photo voltaic (PV) cell generated DC voltage which will be suitable for Indian climate conditions and applicable for rural health centres. Researchers developed first prototype of TER system with a refrigeration space of 1000 cubic centimeter (1 Liter) by using four numbers of Peltier module (Q_max = 19W) and four numbers of Heat sink fan assembly with thermal resistance of 0.50 ρC/W to increase heat dissipation rate. Experiments were conducted on developed prototype of thermoelectric refrigeration system and result shows a temperature reduction of 11.5ρC in refrigeration space with respect to 30ρC ambient temperature.

5 illus, 2 tables, 9 ref

000486   Rama Raju K;Cinitha A;Iyer N R (NO, CSIR-Structural Engineering Research Centre, CSIR Campus, Taramani, Chennai-600 113, Email: krraju@serc.res.in) : Seismic performance evaluation of existing RC buildings designed as per past codes of practice. Sadhana 2012, 37(2), 281-97.

Assessing the capacity of existing building as per the present codes of practice is an important task in performance-based evaluation. In order to enhance the performance of existing buildings to the present level of ductile design prescribed by present codes and find the retrofit or design a rehabilitation system, there is an urgent need to assess accurately the actual lateral load resistance and the potential failure modes. In this paper, a typical 6-storey reinforced concrete (RC) building frame is designed for four design cases as per the provisions in three revisions of IS: 1893 and IS: 456 and it is analysed using user-defined (UD) nonlinear hinge properties or default-hinge (DF) properties, given in SAP 2000 based on the FEMA-356 and ATC-40 guidelines. An analytical procedure is developed to evaluate the yield, plastic and ultimate rotation capacities of RC elements of the framed buildings and these details are used to define user-defined inelastic effect of hinge for columns as P-M-M and for beams as M3 curves. A simplified three parameter model is used to find the stress-strain curves of RC elements beyond the post yield region of confined concrete. Building performance of structural components in terms of target building performance levels are studied with the nonlinear static analysis. The possible differences in the results of pushover analysis due to default- and user-defined nonlinear component properties at different performance levels of the building are studied.

8 illus, 5 tables, 17 ref

000485   Raghunath R;Reddy N R;Ceena S;Datta N;Rao B S;Murali P V;Venugopal (ISTRAC, Indian Space Research Organization, Bangalore, Email: rag.istrac@gmail.com) : Profile measurement technique of 32 meter antenna reflector for Indian deep space network system. Mfg Technol Today 2012, 11(3), 11-14.

ISRO ambitious program "Chandrayaan mission" initiated the establishment of a ground station for Telemetry and Tracking of chandryaan satellite. The ground station was configured with a 32 meter antenna system capable to meet chandryaan mission and also having capability of telemetry and tracking deep space objects. The antenna system is designed, manufactured, tested and successfully installed at Byalallu village near Bangalore with public and private industrial participation. One of the major challenges in this project was to realize a reflector of 32 meter diameter in size having a profile accuracy of 0.3mm rms. The challenge was in terms of manufacturing and measurement techniques used to measure with close tolerances of large surface area. This paper deals with the measurement techniques of antenna reflector surface using a laser tracker instrument.

8 illus, ref

000484   Pishnamazi M;Marjani A;Shirazian S; Samipurgiri M (Petroleum Engineering Dep, Iranian Central Oil Fields Company (ICOFC), Tehran, Iran, Email: shirazian@iust.ac.ir) : Mathematical modeling and numerical simulation of wastewater treatment unit using CFD. Oriental J Chem 2012, 28(1), 51-8.

This paper presents mathematical modeling and numerical simulation of hydrodynamics of a mixer used for wastewater treatment. The simulation is based on solving conservation equations for mixer. Swirl flow is considered for flow behavior in the mixer. The geometry of mixer was divided in to subdomains including fixed and mobile parts. Impeller was considered as mixing device. The model equations are solved by using computational fluid dynamics (CFD) techniques. Velocity distributions were obtained through solving the governing equations. The simulations results showed that there are some dead zones which reduce the efficiency of the mixing process. The modeling findings also revealed that velocity of impeller is a key parameter for increasing mixing efficiency.

6 illus, 10 ref

000483   Pinar A M;Gullu A;Taskin S (Mechanical and Metal Technologies Dep, Celal Bayar Univ, 45400 Turgutlu-Manisa, Turkey, Email: ahmet.pinar@cbu.edu.tr) : Statistical investigation of hydraulic driven circular interpolation motions. Sadhana 2012, 37(5), 557-68.

In this study, a twin-axis gantry has been structured to examine hydraulic driven positioning skills of the curvilinear motions based on ISO 230-4 standard entitled 'Circular tests for numerically controlled machine tools'. The system is controlled by a path and position control module of a PLC device. As a result of the experiments conducted based on the full factorial design, the effects of piston diameter, feed rate, radius and their two-way interactions on the circularity error are determined through analysis of variance. Accordingly, minimum circularity error is obtained with the piston diameter of 63 mm, inertia load of 12:5 kg, radius of 5 mm and feed rate of 50 mm/min as 0.345 mm. Circularity error increases with the increase of inertia load, radius and feed rate, and declines with the increase of piston diameter. Lastly, piston diameter has the greatest effect on the circularity error change and followed by radius, feed rate, piston diameter-radius, radius-feed rate, piston diameter-feed-rate, inertia load, piston diameter-inertia load, and inertia load-radius factors and interactions.

7 illus, 3 tables, 23 ref

000482   Paul A K (1602 Fiona, Hiranandani Estate, G. B. Road, Patlipada, Thane-400 607, Email: arunp_26@vsnl.net) : Qualitative study of status of indigenous arc welding equipments in India. Indian Weld J 2011, 44(3), 58-66.

Energy contributes to less than 2% of arc welding process cost. However, the way energy is controlled dynamically in the weld gap, its role becomes catalytic in nature to the whole process, beyond weld gap. In open or close loop, manual, semi-automatic or automatic mode of operation, power source is lone actuating element in the whole arc welding process influencing not only output characteristics, but also on other input elements. Welding equipment together with efficient method converts arc welding process load as efficient in electrical energy domain. Matching of power source and equipment is essential. However, in many developing countries in the world the matching is yet to take place causing a lot of all round concerns, wastage and productivity are a few of them. Concern is, India being a large size large growing country, also falls in that category. Indian process is heavily inclined to SMAW process using old fashioned equipments. Among population of arc welding equipments, CC power sources are dominant. This makes, ironically enough, data generation and its analysis easy. As it is difficult to have direct and correct statistical data, this article takes the route of qualitative analysis on the status of arc welding equipments in India.

4 illus, 7 tables, 23 ref

000481   Pascual B;Adhikari S (School of Engineering, Swansea Univ, Singleton Park, Swansea SA2 8PP, UK, Email: S.Adhikari@swansea.ac.uk) : Reduced plynomial chaos expansion method for the stochastic finite element analysis. Sadhana 2012, 37(3), 319-40.

Stochastic finite element analysis of elliptic type partial differential equations is considered. A reduced method of the spectral stochastic finite element method using polynomial chaos is proposed. The method is based on the spectral decomposition of the deterministic system matrix. The reduction is achieved by retaining only the dominant eigenvalues and eigenvectors. The response of the reduced system is expanded as a series of Hermite polynomials, and a Galerkin error minimization approach is applied to obtain the deterministic coefficients of the expansion. The moments and probability density function of the solution are obtained by a process similar to the classical spectral stochastic finite element method. The method is illustrated using three carefully selected numerical examples, namely, bending of a stochastic beam, flow through porous media with stochastic permeability and transverse bending of a plate with stochastic properties. The results obtained from the proposed method are compared with classical polynomial chaos and direct Monte Carlo simulation results.

19 illus, 3 tables, 40 ref

000480   Paliwal N;Sharma R;Chand M;Ojha V N (NO, National Physical Laboratory (CSIR), Dr K. S. Krishnan Marg, New Delhi, Email: rina@nplindia.org) : Surface preparation of crystal and characterization of surface roughness using power spectral density analysis. Mfg Technol Today 2012, 11(3), 5-10.

In the present paper authors report crystal surface preparation and analysis of optical surface finish of the Lithium Niobate (LiNbO3) crystal. For preparation of crystals fine abrasive powders (aluminum oxide) of different grain size were used in smoothing and polishing processes. Surface characterization was carried out by imaging the crystal surface with traceable optical profiler in vertical scanning interferometry at magnification objective 2.5X with VisionTM software. The analysis of surface roughness using power spectral density (PSD) function has been carried out and an attempt has been made to correlate PSD analysis with roughness profiles of optical surfaces.

12 illus, 3 tables, 4 ref

000479   Pal P K;Sakrikar R;Sarngadharan P V;Sharma S; Shrivastava V K;Dave V;Singh N;Das A P (Division of Remote Handling and Robotics, Bhabha Atomic Research Centre, Mumbai-400 085, Email: pkpal@barc.gov.in) : Development of an AGV-based intelligent material distribution system. Curr Sci 2011, 101(8), 1028-35.

Material distribution is a special case of the more general requirement for material transfer in a manufacturing environment, and as such it permits simpler solutions. The present article describes an implemented solution for the material distribution problem in the machining shop of an automotive factory using automated guided vehicles (AGVs). We briefly describe the AGV and its associated material handling system, and then describe the intelligent components and their underlying algorithms, which, when put together, create an intelligent distribution system that autonomously assesses demands for materials and accordingly plans, prioritizes and executes deliveries. The system has been tested extensively in a mock environment in our laboratory, the results for which have been reported here.

8 illus, 14 ref

000478   Padhee S;Nayak N;Panda S K;Dhal P R;Mahapatra S S (Manufacturing Science and Technology Dep, Veer Surendra Sai Univ of Technology, Sambalpur-768 018, Email: soymyakantpadhee2011@gmail.com) : Multi-objective parametric optimization of powder mixed electro-discharge machining using response surface methodology and non-dominated sorting genetic algorithm. Sadhana 2012, 37(2), 223-40.

Powder mixed electro-discharge machining (EDM) is being widely used in modern metal working industry for producing complex cavities in dies and moulds which are otherwise difficult to create by conventional machining route. It has been experimentally demonstrated that the presence of suspended particle in dielectric fluid significantly increases the surface finish and machining efficiency of EDM process. Concentration of powder (silicon) in the dielectric fluid, pulse on time, duty cycle, and peak current are taken as independent variables on which the machining performance was analysed in terms of material removal rate (MRR) and surface roughness (SR). Experiments have been conducted on an EZNC fuzzy logic Die Sinking EDM machine manufactured by Electronica Machine Tools Ltd. India. A copper electrode having diameter of 25 mm is used to cut EN 31 steel for one hour in each trial. Response surface methodology (RSM) is adopted to study the effect of independent variables on responses and develop predictive models. It is desired to obtain optimal parameter setting that aims at decreasing surface roughness along with larger material removal rate. Since the responses are conflicting in nature, it is difficult to obtain a single combination of cutting parameters satisfying both the objectives in any one solution. Therefore, it is essential to explore the optimization landscape to generate the set of dominant solutions. Non-sorted genetic algorithm (NSGA) has been adopted to optimize the responses such that a set of mutually dominant solutions are found over a wide range of machining parameters.

8 illus, 5 tables, 41 ref

000477   Mukherjee D;Rao B N;Prasad A M (Structural Engineering Division. Civil Engineering Dep, Indian Institute of Technology Madras, Chennai-600 036, Email: bnrao@iitm.ac.in) : Cut-HDMR-based fully equivalent operational model for analysis of unreinforced masonry structures. Sadhana 2012, 37(5), 609-28.

Mesoscale models are highly competent for understanding behaviour of unreinforced masonry structures. Their only limitation is large computational expense. Fully Equivalent Operational Model forms an equivalent mathematical model to represent a particular phenomenon where explicit relationship between inputs and outputs are unknown. This paper explores the ability of a major variant of High Dimensional Model Representation (HDMR) technique, namely Cut-HDMR, to construct the most efficient Fully Equivalent Operational Model for nonlinear finite element analysis of mesoscale model of an unreinforced masonry structure. Conclusions are reached on various aspects such as, suitability of interpolation schemes and order of Cut-HDMR approximation.

11 illus, 7 tables, 22 ref

000476   Moona G;Chaudhary K P (Standards of Dimension, National Physical Laboratory (CSIR), Dr. K. S. Krishnan Marg, New Delhi, Email: girijamoona1@gmail.com) : Stylus bending effects on CMM measurements and its stylus characterisation. Mfg Technol Today 2012, 11(3), 27-30.

Coordinate Measuring Machines (CMMs) are widely used for a large range of precise measurement tasks. These tasks are expected to be carried out with increasing accuracy, speed and flexibility, as well as the ability to operate under shopfloor conditions. CMM Probe is the interface between coordinate measuring machine and work piece and it is responsible for the coordinate measurement accuracy. The CMM probe acts as a switch by stopping the movement of CMM and freezes the dimensional values as the contact between work piece and probe is made. One of the more prevalent kinds of CMM probes is the Touch Trigger Probe (TTP). TTPs work by sensing the impact of the stylus tip with the work piece. The aim of this study is to determine whether various probe head configurations and probing forces would have an effect on the CMM's ability to repeatedly measure a dimensional feature. During this study it was realized that probing force, stylus shaft length and stylus tip roundness plays a crucial role in measurement. Relevant data from the study is presented.

5 illus, 13 ref

000475   Mohite A S;Nanavati J I;Patel P V (Mechanical Engineering Dep, Faculty of Technology and Engineering Baroda Univ, Baroda, Email: mohit21@yahoo.com) : Energy efficient design of mechanical exhaust system. J Envir Res Dev 2012, 6(4), 1072-7.

This work presents optimum design of exhaust system used for fumes and smoke generated by various processes, which carry with them acidic droplets. This system is also used for circulation and ventilation of the fresh air in the industrial sheds and building. It is used as HVAC (Heating Ventilating and Air Conditioning Applications). This system is designed with compact assembly of impeller, casing and motor. It is made with customized specification to meet the requirement of different industries. It is designed with variable speed, so that it can be used to control the combustion, guide waste exhaust gases, coarse dust or chips, mixed dust with large shavings or lighter amounts of fine dust. Experimentally, we have studied the flow conditions at various locations and with different types of fumes and smoke. As a result, we reached the conclusion that it is a very efficient exhaust system which makes the environment clean and free from fumes and smoke. The portability of this system makes it a multi usage system.

6 illus, 17 ref

000474   Meenal M;Eldho T I (Civil Engineering Dep, Indian Institute of Technology Bombay, Mumbai-400 076, Email: meenal@iitb.ac.in) : Simulation-optimization for groundwater contamination remediation using Meshfree point collocation method and particle swarm optimization. Sadhana 2012, 37(3), 351-69.

Remediation of the groundwater contamination problem is a tedious, time consuming and expensive process. Pump and treat (PAT) is one of the commonly used techniques for groundwater remediation in which the contaminated groundwater is pumped, treated and put back to the aquifer system or other sources. Developing simulation-optimization (S/O) model proved to be very useful in the design process of an effective PAT system. Simulation models help in predicting the spatial and temporal variation of the contamination plume while optimization models help in minimizing the cost of pumping. Generally, grid or mesh based models such as Finite Difference Method (FDM) or Finite Element Methods (FEM) is used for the ground-water flow and transport simulation. But it is found that grid/mesh generation is a time consuming process. Therefore, recently Meshfree (MFree) based numerical models are developed to avoid this difficulty of meshing and remeshing. MFree Point Collocation Method (PCM) is a simple meshfree method used for the simulation of coupled groundwater flow and contaminant transport. For groundwater optimization problems, even though number of methods such as linear programming, nonlinear programming, etc. are available, evolutionary algorithm based techniques such as genetic algorithm (GA) and particle swarm optimization (PSO) are found to be very effective. In this paper, a simulation model using MFree PCM for confined groundwater flow and transport and a PSO based single objective optimization model are developed and coupled to get an effective S/O model for groundwater remediation using PAT. The S/O model based on PCM and PSO is applied for a polluted hypothetical confined aquifer and its performance is compared with Finite Element Method-Binary Coded Genetic Algorithm (FEM-GA) model. It is found that both the models are in good agreement with each other showing the applicability of the present approach. The PCM-PSO based S/O model is simple and more effective in groundwater contamination remediation design using PAT.

12 illus, 3 tables, 26 ref

000473   Leena G;Ray G (Electrical and Electronics Engineering Dep, Faculty of Engineering and Technology, Manav Rachna International Univ, Faridabad-121 003, Email: leenagjeevan@rediffmail.com ) : Set of decentralized PID controllers for an n-link robot manipulator. Sadhana 2012, 37(3), 405-23.

Class of stabilizing decentralized proportional integral derivative (PID) controllers for an n-link robot manipulator system is proposed. The range of decentralized PID controller parameters for an n-link robot manipulator is obtained using Kharitonov theorem and stability boundary equations. Basically, the proposed design technique is based on the gain-phase margin tester and Kharitonov's theorem that synthesizes a set of PID controllers for the linear model while nonlinear interaction terms involve in system dynamics are treated as zero. The stability analysis of the composite system with the designed set of decentralized PID controllers is investigated by incorporating bounding parameters of interconnection terms in LMI formulation. From the range of controller gains obtained by the proposed method, a genetic algorithm is adopted to get an optimal controller gains so that the tracking error is minimum. Simulation results are shown to demonstrate the applicability of the proposed control scheme for solution of fixed as well as time-varying trajectory tracking control problems.

13 illus, 1 table, 23 ref

000472   Lakshmana Rao C (Applied Mechanics Dep, Indian Institute of Technology Madras, Chennai-600 036, Email: rajeshpnair@gmail.com) : Simulation of depth of penetration during ballistic impact on thick targets using a one-dimensional discrete element model. Sadhana 2012, 37(2), 261-79.

One-dimensional discrete element model for the ballistic impact is used to determine the depth of penetration of a bullet on a thick target. Discrete Element Method (DEM) is a numerical tool where a continuum is modelled as a network of masses connected by normal springs. A one-dimensional discrete element model is developed to obtain the displacements and forces associated with the ballistic impact on a thick target. The depth of penetration of the penetrator into the target is calculated from these DEM results. The simulated results of depth of penetration are found to be in reasonable agreement with the simulation results of other numerical approaches that are available in the literature.

11 illus, 1 table, 22 ref

000471   Kusano H (NO, Changer & Dresser, Inc., Anniston, Ala, Email: hiro@changer-dresser.com) : Electrode dressing makes a better spot weld. Indian Weld J 2011, 44(3), 110-14.

10 illus, 1 table

000470   Hashemi-Dehkordi S M;Abu-Bakar A R;Mailah M (Applied Mechanics Dep, Faculty of Mechanical Engineering, Univ Teknologi Malaysia, 81310 Skudai, Johor, Malaysia, Email: s.mahdi.hashemi.d@gmail.com) : Reducing friction-induced vibration using intelligent active force control (AFC) with piezoelectric actuators. Sadhana 2012, 37(6), 637-55.

In this paper, a novel approach to reduce the effect of mode coupling that causes friction induced vibration (FIV) is proposed by applying an intelligent active force control (AFC)-based strategy employing piezoelectric actuators with hysteresis effect to a simplified two degree-of-freedom mathematical model of a friction-induced vibration system. At first, the model is simulated and analysed using a closed loop pure Proportional-Integral-Derivative (PID) controller. Later, it is integrated with the intelligent AFC with fuzzy logic (FL) estimator and simulated under similar operating condition. After running several tests with different sets of operating and loading conditions, the results both in time and frequency domains show that the PID controller with the intelligent AFC is much more effective in reducing the vibration compared to the pure PID controller alone.

1 table, 28 illus, 26 ref

000469   Harris I D (NO, Edison Welding Institute, Columbus, Ohio, Email: iharris@ewi.org) : Welding advances in tube and pipe applications. Indian Weld J 2011, 44(3), 104-9.

11 illus, 4 ref

000468   Gupta M;Monga I;Garg H C (Mechanical Engineering Dep, U.I.E.T., Kurukashetra) : Experimental set-up for a channel having heated plate with inclined blocks and equilateral traingles as an obstacle. J Envir Res Dev 2012, 6(4), 1078-82.

Heat transfer enhancement is the process of improving the performance of heat exchanger systems. Large numbers of attempts have been made to reduce the size and cost of the heat exchangers. Compact heat exchangers are widely used in many industries like chemical, electronics, aerospace, HVAC, process industry etc. So the improvement in their performance with respect to reducing manufacturing costs by using less material or lowering operating cost by reducing energy loss is of great technical, economical, and, not least ecological importance. The performance improvement is necessary in heat exchangers having gases as one of the fluid because the thermal resistance of gases is about 10-50 times as large as of liquids. Achieving higher heat transfer rates through various augmentation techniques can result in substantial energy savings, more compact and less expensive apparatus with higher therrnal efficiency. This paper suggests a way to enhance the heat transfer rate by using a heated plate with inclined blocks in a channel along with equilateral triangles as obstacle.

1 illus, 11 ref

000467   Gupta A;Kundra T K (Mechanical and Automation Engineering Dep, Maharaja Agrasen Institute of Technology, Sector-22, Rohini, Delhi-110 086, Email: anil_gupta10@hotmail.com) : Review of designing machine tool for leanness. Sadhana 2012, 37(2), 241-59.

As an ideology, Leanness is not a new concept but still researchers strive for developing new methods to reduce almost all kinds of identified wastages at almost every stage and in every activity - right from design till delivery of final product to the end-customer. Newly developed manufacturing ideologies, paradigms and systems are always critically examined from the point of view of leanness. In other words, leanness is becoming an important evaluation tool to compare the recently developed/pioneered approaches. There has been a gradual evolution of the leanness over the years from the shop floor level of a manufacturing (automobile) organization to almost every operational and management aspect now. The Leanness has undergone and still is undergoing a process of continuous and never-ending evolution due to its inherently built dynamic concept of continuous improvement. Although in the literature a lot of work has been reported to the application of lean tools, principles, theories and methodologies to production systems, but a very few is evident in the area of Lean design process of a product and machine tool. For this reason an attempt is being made here to focus a significant proportion of this paper on evolutionary aspect of leanness from manufacturing to design stage. Also, this paper reviews the concepts and practices being followed till date by the industrialists, researchers and academicians in applying lean tools and techniques in the design of product and machine tools along with the methods to measure the lean improvements in the systems.

3 illus, 78 ref

000466   Ghosh A;Pratihar D K;Amarnath M V V;Dittrich G;Mueller J (NO, Bengal Engineering and Science Univ, Howrah-711 103, Email: dkpra@mech.iitkgp.ernet.in) : Fuzzy clustering of mechanisms. Sadhana 2012, 37(5), 539-66.

During the course of development of Mechanical Engineering, a large number of mechanisms (that is, linkages to perform various types of tasks) have been conceived and developed. Quite a few atlases and catalogues were prepared by the designers of machines and mechanical systems. However, often it is felt that a clustering technique for handling the list of large number of mechanisms can be very useful, if it is developed based on a scientific principle. In this paper, it has been shown that the concept of fuzzy sets can be conveniently used for this purpose, if an adequate number of properly chosen attributes (also called characteristics) are identified. Using two clustering techniques, the mechanisms have been classified in the present work and in future, it may be extended to develop an expert system, which can automate type synthesis phase of mechanical design. To the best of the authors' knowledge, this type of clustering of mechanisms has not been attempted before. Thus, this is the first attempt to cluster the mechanisms based on some quantitative measures. It may help the engineers to carry out type synthesis of the mechanisms.

2 illus, 2 tables, 23 ref

000465   Gaidhane V H;Hote Y V;Vijander Singh (Instrumentation and Control Engineering Dep, Netaji Subhas Institute of Technology, Delhi Univ, New Delhi-110 078, Email: vilasgd612@gmail.com ) : An efficient similarity measure technique for medical image registration. Sadhana 2012, 37(6), 709-21.

In this paper, an efficient similarity measure technique is proposed for medical image registration. The proposed approach is based on the Gerschgorin circles theorem. In this approach, image registration is carried out by considering Gerschgorin bounds of a covariance matrix of two compared images with normalized energy. The beauty of this approach is that there is no need to calculate image features like eigenvalues and eigenvectors. This technique is superior to other well-known techniques such as normalized cross-correlation method and eigenvalue-based similarity measures since it avoids the false registration and requires less computation. The proposed approach is sensitive to small defects and robust to change in illuminations and noise. Experimental results on various synthetic medical images have shown the effectiveness of the proposed technique for detecting and locating the disease in the complicated medical images.

5 illus, 4 tables, 16 ref

000464   Datta G L (NO, K L Univ, Guntur-522 502, Email: gldatta_05@yahoo.co.in) : Present status of and future direction for welding technology in India. Indian Weld J 2011, 44(3), 81-5.

2 illus, 2 tables

000463   Das R;Das B K;Shukla R;Prabaharan T;Anurag Shyam (Energetics and Electromagnetics Division, Bhabha Atomic Research Centre, Autonagar, Visakhapatnam-530 012, Email: rashmita78@gmail.com) : Analysis of electrical explosion of wire systems for the production of nanopowder. Sadhana 2012, 37(5), 629-35.

Nanoscience and nanotechnology continue to grow as fields of scientific research and commercial development as many fundamental properties are size dependent on the nano scale. There are so many techniques for the production and characterization of various ultra fine powders. To gain a fundamental understanding of size dependant properties of matter in the nanometer size regimes and to develop nanoscale materials into useful devices to benefit society requires detailed study of the experimental methods, better methods of sample preparation of mono dispersed material in large quantities, and development of nanoparticles characterization methods. Exploding wire method is one such method for the production of metal and metal oxide nanoparticles capable of producing bulk amount of metal nanoparticles at low cost. With the intention of developing better exploding wire system for the production of nanoparticle and to understand the nanoparticle formation process, we have developed two systems in the way of optimization of the experimental set-up for final production of nanoparticles. The detail analysis of the systems and its effect on the nanoparticles has been described.

7 illus, 7 ref

000462   Biyikoglu A;Oztoprak H (Mechanical Engineering Dep, Faculty of Engineering, Gazi Univ, Celal Bayar Boulevard, 06570 Maltepe, Ankara, Turkey, Email: abiyik@gazi.edu.tr) : Enhancement of cell characteristics via baffle blocks in a proton exchange membrane fuel cell. Sadhana 2012, 37(2), 207-22.

In this study, the effects of baffle blocks located in the flow channel on fuel cell characteristics were investigated. The higher current densities were obtained from the cells with blockage than without blockage. It was observed that the gap between the tip of the baffle block and the channel wall had a significant effect on the current density produced and on the convergence of solutions. The number and the size of blocks that are providing the highest current density from the cell were determined. No significant effects were observed in the polarization curves for cells with more than four blocks and gap ratio of 0.3. A parametric study was conducted to investigate the effect of the relative humidity and velocity of inlet gases on cells with four blocks and gap ratio of 0.3. It was concluded that the current density is strongly dependent on the relative humidity for low inlet velocities and on the other hand, on the inlet velocity for low relative humidities.

10 illus, 7 tables, 14 ref

000461   Bhatnagar G;Raman B (Electrical and Computer Engineering Dep, Windsor Univ, Windsor-N9C 1M2, ON, Canada, Email: goravb@uwindsor.ca) : Wavelet packet transform-based robust video watermaking technique. Sadhana 2012, 37(3), 371-88.

In this paper, a wavelet packet transform (WPT)-based robust video watermarking algorithm is proposed. A visible meaningful binary image is used as the watermark. First, sequent frames are extracted from the video clip. Then, WPT is applied on each frame and from each orientation one sub-band is selected based on block mean intensity value called robust sub-band. Watermark is embedded in the robust sub-bands based on the relationship between wavelet packet coefficient and its 8-neighbour (Dg) coefficients considering the robustness and invisibility. Experimental results and comparison with existing algorithms show the robustness and the better performance of the proposed algorithm.

17 illus, 3 tables, 25 ref

000460   Barman S;Chatterjee S;Naskar S K;Sen R (NO, Central Mechanical Engineering Research Institute (CMERI), Durgapur-713 209, Email: sbarman@cmeri.res.in) : Performance verification of high resolution angle measuring equipment by laser interferometry technique. Mfg Technol Today 2012, 11(3), 15-18.

At present manufacturing sectors are capable to produce complex components within small tolerance zone in the tune of nano-range at one machining center due to vast advancement of digital electronics and microprocessor. To measure those components high resolution measuring equipment are needed both for linear and angular measurement. For small angle measurement, in the sub-second range, micro-optic auto-collimator or micro-optic angle dekker are used. The performance of these measuring systems are not perfectly accurate due to the error in measuring scale which will change over time to time due to wear, damage and effect of environmental conditions. Analysis of these errors using a laser measurement system provides the user with a way to achieve better accuracy and hence higher quality output from measuring process. In this communication, an innovative technique to measure the angular scale error of auto-collimator and angle dekker by a laser interferometer calibration system has been discussed and the performance accuracy of those equipment has been verified.

4 illus, 5 ref

000459   Ayesha A;Abubacker M N;Rampradheep G S; Sivaraja M (Civil Engineering Dep, Kongu Engineering College, Perundurai, Erode, Tamil Nadu, Email: abubacker_nct@yahoo.com) : Bacterial mineral precipitation to enhance serviceability of concrete. Biosci Biotechnol Res Asia 2012, 9(2), 789-94.

Concrete is found to be an essential building material. Though concrete is quite strong mechanically, it suffers from several drawbacks, such as low tensile strength, permeability to liquids, corrosion of reinforcement, susceptibility to chemical attack. Consequently concrete develops cracks affecting the durability of the structure. Modifications have been made from time to time to overcome such drawbacks of concrete all of which are not easy and result oriented. Therefore bacterial concrete technique is developed using some bacterial species like Bacillus subtilis, B. pasteruii and Pseudomonas aeruginosa. The aim of this study is to use B. subtilis bacterial culture to produce microbial concrete. Bacterial concrete is a novel technique in which the bacterial enzymes induce carbonate precipitation resulting from metabolic activities of B. subtilis in concrete to improve the overall behaviour of concrete. The microbial induced calcium carbonate precipitation (MICCP) involves a series of biochemical reactions in which the microbe B. subtilis produces urease, which catalyzes urea to produce CO₂ and ammonia, resulting in an increase of pH in the microbial concrete during which the ions Ca₂⁺ and Co₂^-3 precipitate out as calcium carbonate in the form of calcite (CaCO₃) which in turn has crack healing properties. This study is focused on the compressive strength, water absorption rate, split tensile strength of cement mortar (bacterial concrete), urease production capacity of B. subtilis bacteria as well as the evaluation of calcite mineral producing capacity by standard methodology. The development of the bacterial concrete using B. subtilis will provide the basis for an alternative and high quality concrete which will be environmentally safe, improve the resistance to cracks and enhance the durability of building materials induce carbonate precipitation resulting from metabolic activities of B. subtilis in concrete to improve the overall behaviour of concrete in compressive strength of cement mortar. The bacterial induced calcium carbonate precipitation (MICCP) involves a series of biochemical reactions in which B. subtilis produce urease, which catalyzes urea to produce CO₂ and ammonia, resulting in an increase of pH in the bio cement where ions Ca⁺ and CO³ precipitate calcium carbonate in the form of Calcite (CaCO₃) which in turn has crack healing properties.

3 illus, 4 tables, 12 ref

000458   Ahmad R R (Ocean Engineering Dep, Amir Kabir Technology Univ, 15914 Tehran, Iran, Email: rahbar@aut.ac.ir) : Plastic collapse load of corroded steel plates. Sadhana 2012, 37(3), 341-9.

Corrosion is one of the detrimental phenomena which reduces strength of structures. It is common practice to assume a uniform thickness reduction for general corrosion. Since the actual corroded plate has rough surfaces, to estimate the remaining strength of corroded structures, typically a much higher level of accuracy is required. The main aim of present work is to study plastic collapse load of corroded steel plates with irregular surfaces under tension. Non-linear finite element method by using computer code ANSYS was employed to determine plastic collapse load. By comparing the results with uniform thickness assumption, a reduction factor was proposed. It is found that by uniform thickness assumption, plastic collapse load of corroded plates are overestimated.

4 illus, 6 tables, 7 ref

000457   Affandi A;Husain M (Elect. & Comp. Eng. Dep, King Abdul Aziz Univ, Jeddah, Saudi Arabia, Email: adnanaffandi@yahoo.co.uk) : Frequency selective (tuning using varactor diode) doppler signal detection using negative resistance diode. Invertis J Sci Technol 2013, 6(3), 140-9.

Theory is presented for the Doppler signal detection with a negative-resistance diode oscillator operating simultaneously as a signal source and Doppler signal detector. The theory is based on a realistic model of the oscillator, including an object passing in front of an antenna, and includes the previous treatments as the limiting cases. The effect of the bias circuit taking out the Doppler signal on the RF operation of the oscillator is taken into account self-consistently. The frequency down-conversion with a free-running oscillator is also investigated. Conversion gain is demonstrated by the experiment using a Gunn oscillator with a movable load. In this paper we are presenting a technique to improve the existing paper technique with the help of a varactor diode which electronically tunes the Negative Resistance Diode and hence makes the system frequency selective.

6 ref

024784   Zou Z L;Li N;Li D Y (Chemistry Dep, School of Chemical Engineering & Technology, Harbin Institute of Techn, Harbin, P.R. China, Email: lininghit@yeah.net) : Conversion coating treatment of zinc surface by a vanadate solution. Asian J Chem 2011, 23(3), 1104-6.

Chemical conversion coating on zinc surfaces was performed by immersion in a solution containing vanadate. Corrosion behaviour of zinc surfaces was investigated using electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy. According to the results, the vanadium-treated layer significantly improved the corrosion resistance of zinc surfaces in contact with 3.5% NaCl solution. In comparison of the chromium-treated layer, the vanadium-treated layer also exhibits better corrosion resistance. The treated zinc surface mainly consists of vanadium and oxygen, which mainly exist as V₂O₅, VO₂, and its hydrates.

2 illus, 1 table, 9 ref