005383   Tyagi G K;Sharma D (The Technological Institute of Textile & Sciences, , Bhiwani-127 021) : Low stress characteristics of polyester cotton MVS yarn fabrics. Indian J Fibre Text Res 2005, 30(1), 49-54.

The effects of some jet spinning parameters on the low-stress characteristics of scoured and finished fabrics woven. with polyester-cotton jet-spun yarns have been studied. It is observed that the compressional energy, shear energy and coefficient of friction of MVS yarn fabrics decrease initially when the twisting jet pressure is increased from 4 kg/cm² to 5 kg/cm² and increase thereafter with the further increase in twisting jet pressure. An increase in nozzle distance on the MVS spinner, on the other hand, causes a significant decrease in these properties. Furthermore, the use of fine yarns decreases compressional energy and coefficient of friction, and the fabrics made from yarn spun with higher jet pressure and wider nozzle distance have higher bending rigidity. The chemical finishing significantly decreases the compressional energy, shear energy, coefficient of friction and bending rigidity.

4 illus, 4 tables, 12 ref

005382   Subramanian S;Peer Mohamed A (Department of Textile Technology, A C College of Technology, Chennai-600 025) : Studies on combined effect of heating of roving and space between the aprons of ring frame drafting system on yarn quality. Indian J Fibre Text Res 2005, 30(1), 94-8.

The combined effect of heating of roving at the break draft zone and space between the aprons of ring frame drafting system on yarn quality has been studied. Heating of roving at the break draft zone of ring frame reduces the friction between the drafting fibres which can be advantageously utilized by reducing the spacing between the aprons, thereby improving the control over the floating fibres. It is observed that the yarn imperfections, faults and elongation - at - break are affected by the heating of roving at the break draft zone and varying the space between the aprons.

^ssc4 tables, 5 ref

005381   Shukla S R;Jajpura L (Department of Fibres and Textile Processing Technology, Institute of Chemical Technology, University of Mumbai, Matunga, Mumbai-400 019) : Immobilisation of amylase by various techniques. Indian J Fibre Text Res 2005, 30(1), 75-81.

The enzyme alpha-amylase was subjected to immobilisation by entrapment and covalent binding methods. Calcium alginate gel entrapment technique was used for the enzyme entrapment. Nylon 6 beads and knitted fabric were the support chosen for the covalent bonding technique using glutaraldehyde with and without chitosan. The characteristics of the immoblised enzyme have been discussed. Covalent bonding gave stability and reusability of the immobilised enzyme than the calcium alginate bead entrapment.

9 illus, 22 ref

005380   Radetic M;Joice D;Jovancic P (Textile Engineering Department, Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11120 Belgrade, Serbia and Mon, ) : Recycled wool-bassed nonwoven material for sorption of acid dyes. Indian J Fibre Text Res 2005, 30(1), 82-7.

The possibility of using a nonwoven material based on recycled wool for sorption of acid dyes from wastewater has been studied. To improve its sorption properties, the recycled wool-based nonwoven material was treated with low-temperature air plasma and/or biopolymer chitosan. These treatments introduced new favourable functional groups and increased the active surface area. Sorption capacity, sorption kinetics as well as the influence of electrochemical properties of fibre, initial dye concentration, pH and temperature on the sorption have been studied. It is observed that the nonwoven recycled wool-based material can be used as an efficient sorbent for removal of acid dyes. Chitosan and plasma+chitosan treatments of the material remarkably improved the sorption properties for AR88 and AR27 dyes, likely because of the increase in amino groups originating from chitosan that are the main sites for binding of dye anions. However, no significant positive effect of low-temperature plasma and/or chitosan treatment of material on sorption of AB113 dye was observed.

4 illus, 2 tables, 27 ref

005379   Prabaharan M;Carneiro N (Polymer Engineering Dep, University of Minho, Guimaraes 4800 058, Portugal) : Effect of low temperature plasma on cotton fabric and its application to bleaching and dyeing. Indian J Fibre Text Res 2005, 30(1), 68-74.

The effect of plasma discharge on the properties of grey cotton fabric has been studied by varying power discharge and number of discharges. To obtain the desired properties of fabric with minimum mechanical and chemical damage to cellulose, the process parameters have been optimized. It is observed that the desired properties can be achieved if the fabric is treated with higher power discharge and for minimum number of discharges. To achieve a high degree of whiteness, a two-stage process is suggested wherein the plasma discharged fabric is further treated with hydrogen peroxide. An acceptable degree of whiteness for dyeing and optical brightening agent (OBA) treatment can be obtained by a two-stage process with the additional benefits of savings in time, thermal energy, water and chemicals. The dyeing property of two-stage processed fabric has also been evaluated and compared with that of the fabric bleached with hydrogen peroxide by the conventional method. The fabric treated with plasma followed by hydrogen peroxide shows excellent dye adsorption even on using very low quantity of salt and a low dyeing temperature.

5 illus, 2 tables, 31 ref

005378   Palaniswamy N K;Peer Mohamd A (Department of Textile Technology, A C College of Technology, Anna University, Chennai-600 025) : Balanced two-ply cotton yarn. Indian J Fibre Text Res 2005, 30(1), 32-6.

The twist set in the cotton single yarn and amount of doubling twist required to produce balanced two-ply yarn have been determined by wet relaxing the yarn from torsional stress and strain. Irrespective of the amount of single yarn twist the amount of twist set in the single yarn is about 45% of the original twist. Balanced two-ply yarn can be produced by giving half of single yarn twist as ply twist in the direction opposite to that of the.single yarn twist.

4 illus, 3 tables, 7 ref

005377   Nair P;Shukla R N (Department of Applied Chemistry, Samrat Ashok Technological Institute, Vidisha-464 001, Email: nandupreeti@yahoo.co.in) : Ipomoea carnea Jacq-A promising non wood source for pulp and paper making. Indian J appl pure Biol 2004, 19(2), 189-95.

Ipomoea cornea Jacq., a shrub that is widely distributed in India, as a useful fibre source for paper making. Initially the raw material was tested for its proximate chemical analysis. The study includes pulping runs by soda and soda anthraquinone process to judge the suitability of the raw material. The investigation evaluates the effect of four additives in soda pulping of I. carnea. The additives used are quinone based additives. The new raw material fiber sources were found to be worthwhile and can be used to produce paper. The effect of additives on the pulping is different with various raw material. The mechanism of pulping differs from process to process. Addition of additives to soda liquor enhances strength properties.

5 tables, 12 ref

005376   Malik S K;Kadian S;Sushil Kumar (Department of Textiles, The Technological Institute of Textile & Sciences, Bhiwani-127 021) : Advances in ink-jet printing technology of textiles. Indian J Fibre Text Res 2005, 30(1), 99-113.

A brief account of various paths used in the development of ink-jet printing for textiles has been reported. This technology has achieved considerable success till the production stage and a lot of R & D work is being done to improve it further. It is a clean and environment-friendly process that reduces printing duration and costs by increasing productivity of pre-production in printing process. The potential applications of ink-jet technology emerged in the past few years have also been presented.

^iia19 illus, 2 tables, 50 ref

005375   Majumdar A;Majumdar P K;Sarkar B (NO, College of Textile Technology, Serampore-742 101) : Application of linear regression, artificial neural network and neuro-fuzzy algorithms to predict the breaking elongation of rotor-spun yarns. Indian J Fibre Text Res 2005, 30(1), 19-25.

The breaking elongation of rotor-spun yarns has been predicted by using linear regression, artificial neural network and neuro-fuzzy models. Cotton fibre properties measured by high volume instrument and yarn count have been used as inputs to the prediction models. Prediction accuracy is found to be better for artificial neural network and neuro-fuzzy models than that for regression model. The relative importance of yam count and cotton fibre properties to rotor yarn elongation has also been studied. Yarn count and cotton fibre micronaire are found to be dominant input factors influencing the breaking elongation of rotor-spun yarns.

4 illus, 5 tables, 24 ref

005374   Lukic S;Asanovic K;Milutinovic Nikolic A (Department of Textile Engineering, Faculty of Technology and Metallur, University of Belgrade, Karnegijeve 4, 11000 Belgrade, Serbia) : Influence of heat treatment on mechanical and sorptional properties of viscose-based nonwovens. Indian J Fibre Text Res 2005, 30(1), 55-9.

The influence of heat treatment on sorptional and mechanical properties of viscose: polypropylene (90:10) blend nonwoven fleeces has been studied. It is observed that the heat treatment improves mechanical properties (rupture resistance and tensile strength) and slightly decreases sorptional properties (degree of water retention and rate of water absorption) of cloths. The-optimum heat-treatment temperature needed to obtain the highest breaking force and water absorption of nonwovens is found to be 165-170°C. Microstructural analysis proves that the nonwovens have the point bonding form of web when heat treatment is performed at optimum temperature.

7 illus, 1 table, 16 ref

005373   Koh J (Department of Textile Engineering, Konkok University, Seoul 143-701, South Korea) : Dyeing properties of a mixed bi-functional reactive dye on a novel regenerated cellulosic fibre. Indian J Fibre Text Res 2005, 30(1), 88-93.

A mixed bi-functional reactive dye has been applied to the regular viscose rayon and the new regenerated cellulosic fibre (enVix®), prepared from cellulose acetate by the hydrolysis of acetyl groups, and their dyeing and fastness properties compared. It is observed that the enVix® exhibits better dyeability than the regular viscose rayon as explained by the differences in the supramolecular structure of these two fibres.

7 illus, 1 table, 11 ref

005372   Kan C W;Chan K;Yuen C W M (Institute of Textiles and Clothing, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China) : Influence of plasma gas on surface composition of low-temperature plasma-treated wool fibre. Indian J Fibre Text Res 2005, 30(1), 60-7.

Wool fibres have been treated with low-temperature plasma (LTP) with oxygen, nitrogen and gas mixture (25:75 hydrogen/nitrogen). It is observed that the chemical composition of wool fibre surface varies differently with the different plasma gases used. The surface chemical composition of the different LTP-treated wool fibres has also been evaluated with FTIR-ATR, XPS and saturated adsorption value. The results reveal that the surface chemical and physical compositions of wool fibre change on LTP treatment. The change in compositions might affect the wool dyeing and finishing processes such as shrinkproofing treatments.

8 illus, 3 tables, 24 ref

005371   Ishtiaque S M;Salhotra K R;Das A;Sukhadeva N S (Department of Textile Technology, Indian Institute of Technology, New Delhi-110 016) : Study on fibre opennes - Its impact on roving drafting force and yarn quality. Indian J Fibre Text Res 2005, 30(1), 26-31.

A detailed analysis on the effect of fibre-to-fibre friction along with the carding parameters on the openness of fibre has been carried out. The fibre openness has been correlated with the drafting force of rovings and properties of silver, roving and yarn. It is observed that the fibre-to-fibre friction has significant influence on the fibre openness. The increase in fibre openness results in decrease in roving drafting force. The nep count and short fibre content of card silver, mass irregularity of card silver, draw frame silver, roving and yarn, total imperfections and yarn tenacity are significantly influenced by the fibre openness.

7 illus, 4 tables, 12 ref

005370   Ghosh S;Amidei C (Eastern Michigan University, , Ypsilanti, Michigan, USA) : Development of a sensor-embedded flexible textile structure for apparel or large area applications. Indian J Fibre Text Res 2005, 30(1), 42-8.

Various optical sensors have been embedded into the flexible textile structures and then attached to the connectors to determine the noise level during demodulation due to the interlacement of the fiber in the fabric structure. These optical sensors, such as Extrinsic Fabry-Perot Interferometer (EFPI), Fiber Bragg Grating (FBG) and Long Period Grating (LPG), are capable of measuring strain and temperature of the devices to which they are attached. LPG sensor can be configured as a chemical sensor. Reflected spectrum from the sensor has been produced by injecting light into the fiber to check the functionality of the sensor. Both EFPI and FBG sensors, successfully embedded into the fabric without any damage, have been found to be functional when demodulated. A brief description of the optical frequency domain reflectometry (OFDR) demodulation method has also been provided.

14 illus, 8 ref

005369   Dutt D;Malik R S;Upadhaya J S;Tyagi C H; Upadhaya M K (Department of Paper Technology, Indian Institute of Technology Roorkee, Saharanpur Campus, Saharanpur-247 001, Email: dutt_dharm@yahoo.com) : Studies on effect of topology on pulp and paper characteristics of Eucalyptus camaldulenosis. Indian J chem Technol 2005, 12(3), 332-40.

Seedlings of Eucalyptus camaldulenosis of same genotype were grown at different geographical locations having distinct pre and post-monsoon ground water levels. It is observed that as the ground water level recedes, balloon like structures known as tyloses develop, which affect the plant anatomy, physico-chemical and pulp and paper making characteristics of E. camaldulenosis. The aging of E. camaldulenosis has marked adverse impact on morphological, physico-chemical composition, pulping and black liquor characteristics along with mechanical strength properties of paper.

5 illus, 7 tables, 28 ref

005368   Canbaz Karakas H;Dayioglu H (Textile Engineering Department, Faculty of Mechanical Engineering, Istanbul Technical University, 34439 Istanbul, Turkey) : Influency of false-twist texturing parameters on teh structural properties of polyester yarn. Indian J Fibre Text Res 2005, 30(1), 37-41.

Structural changes of polyester yarn with false-twist draw texturing parameters have been studied using a high-temerature heater, high texturing speeds, short residence time in the heater and a short yarn path. The dependence of three structural parameters, viz. crystalline orientation, crystal size and birefringence, on texturing tempenuure, yarn residence time in the heater and draw ratio has also been studied. At high texturing speeds, the crystalline orientation and crystal size decrease due to low thermal input. Crystalline orientation tends to increase at high texturing temperatures and draw ratios.

5 fig, 2 plates, 12 ref

005367   Bhattacharya S;Gupta B;Mukherjee A K; Vardarajan R (Department of Textile Technology, Indian Institute of Technology, New Delhi-110 016) : Hydrolytic modification of acrylic fibre-influence of reaction conditions. Indian J Fibre Text Res 2005, 30(1), 13-8.

The chemical modification of acrylic fibre was carried out by alkaline hydrolysis under different reaction conditions. The partial conversion of nitrile groups into carboxylic acid groups was studied as a function of the time and temperature of the reaction. It was found that the hydrolysis reaction is a complex process where side reactions involving the cyclization of hydrolyzed groups become a dominant factor. The formation of various products during the process of hydrolysis was ascertained by infrared spcctroscopy. The crystalline changes and mechanical strength of the fibres as a function of the reaction conditions were also evaluated. The modified fibre showed excellent water retention in deionized and saline water.

11 illus, 16 ref

004304   Varghese T;Manjunath (Harihar Polyfibers and Grasilene Div, Grasim Industries Ltd, Kumarapatnam-581 123) : State-of-the-art technologies and approach to improve chemical recovery efficiency. IPPTA Jl 2005, 17(2), 93-6.

High chemical recovery efficiency of plus 98<37> and almost selfsufficiency in energy with implementation of state-of-the-art cleaner technologies have been dealt with. Some of the major cleaner technologies implemented are Black liquor crystallization in evaporator, High dry solids firing in recovery boilers, Continuous up-gradation of recovery boilers combustion technology, Slow motion slaking in causticizing, Modified lime mud clarification, Two stage sedimentation type dregs washing system, Four stage counter current brown stock washing, Closed compact pressure knotter, Micro processor based electro static precipitator for soda recovery boilers and lime kiln, Process automation with DCS and Conductivity controlled recovery pits.

3 illus, 1 table, 6 ref

004303   Van Wyk B J;Mullen T;Kulkarni S (NO, Air Products South Africa (Pty) Ltd, ) : Investigation into the effect of using oxidized white liquor (Thiosulphate) in the E stage of the bleach plant on the chloride and potassium concentrations in the recovery circuit of the mill. IPPTA Jl 2005, 17(2), 41-7.

The reported mill was experiencing corrosion in the super heater section of the recovery boiler due to high concentrations (1 Wt<37> black liquor solids) of chlorides (CI) and potassium (K) found in the recovery circut. A high concentration of these substances in the black liquor fired to the boiler lowers the first melting point temperature of carryover in the recovery furnace. This can cause acceleration in the fouling rate of the boiler as well as the potential to increase the corrsion rate. The mill does not have a specific method to control chlorides and potassium levels. A purge of the Electrostatic Precipitator catch was carried out at various times to control the sulphur balance. This material has a higher concentration of potassium and chlorides as compared to black liquor. Chlorides and Potassium are purged from the liquor cycle through loses in the recovery circuit due to liquor spills and evaporator wash downs, and through the brown stock washers. As the mill reduces these losses, there will be a further increase in the concentrtaion of these chemicals and another purge method will need to be found. The use of Oxidized White Liquor, where the Na₂S has been oxidized to thiosulphate "OWL(T)", in the Eo stage as a means of effectively purging chlorides and potassium from the recovery cycle has been investigated. A coin GEMS analysis was carried out on a generic mill to calculate the impact on a mill using OWL(T). The data showed that replacing the Eo stage caustic with OWL(T) can reduce the mill's operating coasts and effectively remove chlorides and potassium from the liquor cycle.

8 illus, 1 table, 8 ref

004302   Tara M K;Reddy K P;Jain R (NO, Abhishek Industries Ltd, PCD, Barnala, Punjab) : Chemical recovery in agro residue based mill. IPPTA Jl 2005, 17(2), 103-8.

Wheat Straw, an Agro Residue, is the raw material used for paper manufacture in has been installed based on a conventional Chemical Recovery Unit with 165 TPD of Black Liquor Solids handling capacity in the year 1998, in view of their Corporate commitment for providing a cleaner environment to the society. The efforts were always on to improve continuously the Chemical Recovery operations in tackling the serious technical / operational problems arising out of high Silica, Chlorides and Potassium present in the Wheat Straw Black Liquor. Paper dwells on the issues, remedial actions and best practices implemented to achieve the best Chemical Recovery Efficiency in Wheat Straw based integrated Pulp and Paper Mills.

6 illus, 6 tables

004301   Suresh Khanna S;Ram Kumar;Rao N J;Kanna Babu (NO, Alfa Laval India Ltd, Pune) : Energy conservation approaches in digester house. IPPTA Jl 2005, 17(2), 117-23.

The potential for energy conservation measures in digester house of pulp mill without affecting production, yield of quality has been studied. Energy conservation measures in the pulp mill are discussed. The digester house is a major consumer of energy in terms of steam. The energy consumption in the pulp mills is around 1.6 tonne per tonne of unbleached pulp as steam and 7.0 kWh per tonne of unbleached pulp as electrical energy. There are various possible measures in pulp mill to conserve energy, there are: Indirect steaming of digesters. Optimize digesetrs scheduling by proper control on various parameetrs. Recover heat from continuous relief vapor from digesters. Steam packing of digesters. Two stage steaming of digesters. Recover blow heat from the digesters by suitable displacement of cold blow technique. Use of continuous digesters. Modified/new cooking proess (use of Rapid Displacement Heating).

3 illus, 4 tables, 2 ref

004300   Subramanian S;Vijayakumar T;Singh R; Sankaralingam P;Narayanamurty C H (NO, Tamil Nadu Newsprint and Papers Limited, Kagithapuram-639 136) : Improvement of hardwood pulp quality: optimisation of process and automisation. IPPTA Jl 2005, 17(2), 49-57.

Systematic identification of bottlenecks in hardwood pulping and measures taken to eliminate them are discussed. The major modifications, like, digester automatio, on line Brightness sensor in chlorination stage were carried at the plant, which resulted in substantial improvement in yield and quality of the hardwoord pulp. Other process problems, such as blow delay, reblow, effect of chlorination and cooking variables such as cooking temperature, wood chips charge, cooking time and its impact on pulp properties with respect to quality improvement are discussed.

13 illus, 6 tables, 7 ref

004299   Sharma S K;Verma P;Tiwari K N (NO, Shreyans Industries Ltd, Unit Shreyans Paper, Ahmedgarh, Punjab) : Oxidative alkali extraction in an agro pulp mill. IPPTA Jl 2005, 17(2), 83-6.

Results of plant scale operation of alkali extraction in an Agro based pulp mill employing wheat straw at E, Ep, Eo and Eop stages are discussed. Reduction in chlorinated pulp K. No. at E stage was 38<37>, Ep stage 42<37>, Eo stage 43<37> and Eop stage 58<37> respectively. Gain in alkali extracted pulp brightness over CE stage was 3.2 point at CEp, 3.5 point at CEo and 11.7 point at CEop stages respectively. Gain in final bleached pulp brightness over CEHH was 2 points both in case of CEpHH and CEoHH stages of bleaching at the extra cost of Rs. 328/T and Rs. 70/ T respectively, whereas 4 point gain was found in case of CEopHH at Rs. 214/T extra cost. BOD, COD and colour reduction over CE stage remained between 15 to 20<37>. Whiteness and brightness stability was improved in Oxidative alkali extraction.

2 illus, 2 tables

004298   Ray A K;Vivek Kumar;Dutt D;Mittal K C; Upadhyay J S (Paper Technology Dep, Indian Institute of Technology, Roorkee, Saharanpur Campus, Saharanpur-247 001) : Comparison of ECF bleaching sequences of bagasse. IPPTA Jl 2005, 17(2), 77-82.

Experiments were conducted on bleaching of bagasse pulp using two prospective sequences namely, DED and DEpD. Studies were also made with CEH bleaching sequence for merely comparison purpose. Partially depithed bagasse obtained from a mill were subjected to combination depithing and then separately soda and soda-oxygen pulping were carried out in the laboratory 15 liter Weverk rotating digester. The conditions for soda-oxygen pulp were selected based on earlier findings. The resulting soda pulps were treated with traditional bleaching sequence to be used as a base. The soda-oxygen pulps were treated with short sequence ECF bleaching sequences DED and DEpD- the most economically viable sequences in the ECF bleaching process. On the basis of pulp quality in terms of kappa number, the chemical doses were fixed in all the cases. EDTA was added to stabilize peroxide in peroxide reinforced extraction stage of DEpD sequence. Total twentysix experiments were conducted including two tests with CEH sequences and the rest twelve each on DED and DEpD. The quality of bleached pulp in terms of brightness, yield and tensile index from all the sequences were compared. Finally COD values of the combined effluent were measured to assess the amount of pollutants generated.

12 illus, 4 tables, 10 ref

004297   Ravi K;Rambabu Y;Venkataramanan L;Mutsaddi N; Udupi K M (NO, The Mysore Paper Mills Ltd, Bhadravathi, Karnataka) : Developmental needs of chemical recovery system. IPPTA Jl 2005, 17(2), 87-91.

Chemical Recovery System in The Mysore Paper Mills Ltd., is a conventional one. Technologically the system is old and absolete. With increase in energy cost and environmental restrictions, it is imperative to upgrade the recovery plant with energy efficient and environmental friendly technology. The scheme for the use of falling film evaporation technology in the evaporation process and removal of DCE and augmentation of economiser in Recovery Boiler has been described. The advantages expected are, Energy savings, Increased captive pulp production, Reduced TRS emissions and increased life of ESP and Reduction in furnace all consumption.

2 illus, 3 tables, 2 ref

004296   Rajesh K S;Narasimhan K;Narayanamurty;Mani R (NO, Tamil Nadu Newsprint and Papers Ltd, Kagithapuram, Karur, Tamil Nadu) : A cost beneficial approach to improve hardwood Kraft pulp productivity. IPPTA Jl 2005, 17(2), 59-63.

Improving productivity through low cost solutions is the key for the industry to improve upon its performance so as to meet the global competitiveness. Improving the productivity of hardwood Pulp Street, through a cost beneficial approach has been discussed. The usage of Digester additives on a regular basis has improved the hardwood pulp productivity, with the existing plant facilities. Plant scale trials conducted in hardwood Kraft pulping have been discussed. Different additives were tried and trials were taken under varying conditions, to evaluate their potential in improving the productivity. Active alkali reduction, reduction in knots generation and cost reduction were noticed, in addition to absorbing the cost of the additive. The results are expected to help other Kraft mills in improving production without additional investments.

4 tables, 4 ref

004295   Norden S;Carre G;Lundahl Y;Jain N K (NO, Metso Paper, Sweden) : New bleaching processes and fibreline with state-of-the-art technology. IPPTA Jl 2005, 17(2), 29-34.

Many Indian mills are bleaching the pulp with the sequences CEH or CEHH. The effluent from such a bleach plant contains substantial amounts of color, AOX, and COD and the effluent volume is large. Today more and more stringent environmental demands as well as demands for higher efficiency and larger production levels imply that substantial changes in fibreline technology are necessary. Introduction of zone bleaching according to Metso's ZeTrac^TM process and bleaching the pulp in a light ECF sequence, like (Ze) DP or (Ze) DD, or a TCF sequence, like ZQ (PO), will dramatically reduce the effluent load from bleaching. Ozone bleaching is also cost effective compared with other ECF bleaching sequences, like D(EOP)D, as large amounts of chlorine dioxide and/or peroxide can be replaced with moderate amounts of ozone. Bleaching with the sequence (Ze) DP will generate very small amounts of AOX. The usage of ozone will also make it possible to produce a pulp with a very low OX (organic chlorine) content. The OX content has become more and more important to certain paper grades, especially for those used in the food industry. Laboratory bleaching trials of pulps from Indian raw materials have been presented.

11 illus, 9 tables, 2 ref

004294   Mullen T;Van Wyk B;Kulkarni S (NO, Air Products and Chemicals Ins, USA) : Increased recovery boiler capacity through black liquor oxidation. IPPTA Jl 2005, 17(2), 35-9.

The production rate of a Kraft pulp mill is often limited by the capacity of the mills' recovery boiler. The recovery boiler burns black liquor, a byproduct of the Kraft process, in a water-walled furnace. The inorganic chemicals in the luquor are recovered as a smelt and the heat from the combustion of the organic material produces steam. The capacity of the boiler can be limited by Excessive fouling of the pendant heat transfer surfaces. The maximum acceptable steam production rate, TRS emissions, Excessive corrosion in the lower furnace due to high temperature and Particulate emissions in the flue gas. A mill has various options to alleviate these limitations, including, Air Flow optimization, Oxygen enrichment, High solids firing and Equipment upgrades. One further alternative is to oxidize the black liquor. Black liquor oxidation is an established technology originally used to control Total Reduced Sulfur (TRS) emissions from a direct contact evaporator. However, the process can also be used to relieve a number of boiler capacity limitations. The Riapsa Inc. Kraft mill in Americana Brazil operated an Air Products black liquor oxidation system to increase the capacity of their Low Odor recovery boilers. Previous to its installation, the boilers were at their maximum steaming rate and had a fouling problem. Additionally, the multiple effect evaporator set was at its liquor-processing limit. Results are presented which show a 30 mt/d pulp production increase and a net steam savings of 165 mt/day. The initial capital investment was returned within the first four months of operation.

7 illus

004293   Dhar T R;Kekre P V;Raghuveer (NO, ITC Ltd, Bhadrachalam) : New pulp technology fibreline. IPPTA Jl 2005, 17(2), 125-8.

Elemental Chlorine Free (ECF) bleaching for pulp and paper Industry, based on chlorine dioxide, offers a number of fundamental benefits over traditional methods. Today, Indian Pulp and Paper Industry realises the importance of ECF bleaching along with oxygen delignification. The new fiberline at ITC Ltd, PSPD, unit Bhadrachalam has been described. It is reported to have eliminated elemental Chlorine in its process of bleaching. It is claimed to be the only one of its kind in the country conforming to world class environmental standards. The unit has adopted hot screening, Oxytrac, new genertaion presses both in washing and bleaching supplied by M/s Metso. Oxytrac delignification process is unique in its features to remove 45-50<37> of the remaining lignin after cooking.

5 illus, 4 tables, 6 ref

004292   Chauhan V N;Darab Khan;Padmanabhan N A (JK - CPM, , Fort Songadh) : New chemical recovery boiler. IPPTA Jl 2005, 17(2), 109-15.

Central Pulp Mills Ltd. (CPM) was taken over by JK Group in 1992 and has made steady progress. JK - CPM gradually improved its pulping capacity from 38,000 TPA to 44,000 TPA with addition of one digester and installing BSW IV. For handling equivalent BL solids JK - CPM had a renovated and upgraded Recovery Boiler of 250 TPD BLS firing capacity. With some minor modifications / improvements in Pulp Mill JK - CPM felt that pulp production can further be increased to 48,000 TPA but Recovery Boiler was one of the major constraint. Also after pulp mill modernisation by installing ODL plant, pulp production is expected to touch a figure of 50,000 TPA. Hence, a need of a new Chemical Recovery Boiler was urgently felt to avail the benefits of higher pulp production. Order was placed on Enmas Andritz Pvt Ltd (EAPL), Chennai for supply of a 335 TPD BLS firing capacity Recovery Boiler of single drum (outside of gas path) design with membrane wall of furnace, decantation type hearth, panel type boiler bank and economiser. A state of art of techology Recovery Boiler was designed, supplied, erected and commissioned in a record time of 14 months and 28 days. This was achieved due to one team working and not distinguishing as customer - supplier relationship. All activities were carried out in coordinated way rather than conventionally, thus achieving Boiler commissioning in record time of 14 months and 28 days. This was achieved due to one team working and not distinguishing as customer - supplier relationship. All activities were carried out in coordinated way rather than conventionally, thus achieving Boiler commissioning in record time of 14 months and 28 days. In addition to record time, boiler was stabilized in first start up with 80<37> MCR firing within 72 hours and continued to run for 3 months. A pillar "Early Management" of total Productive Maintenance (Japanese Concept) played remarkable role in this challenging achievement. Various abnormalities / deficiencies and improvements in technology were taken care in TPM methodology. Total 78 fuguais (abnormalities / deficiencies / improvements) were focused during design, manufacture, installation and test run stage. Major advantages achiebved are increase in reduction efficiency, steam generation, boiler runnability and decrease in boiler cleaning time.

2 illus

004291   Bajpai P;Sanjay Kumar;Mishra S P;Mishra O P; Bajpai P K;Varadhan R;Shenoy S C;Mukherjee B (NO, Thapar Centre for Industrial Research and Development, Patiala) : Improving digester prformance through the use of surfactants and AQ. IPPTA Jl 2005, 17(2), 65-75.

The effects of adding AQ and surfactants individually and in combination in Kraft pulping of mixture of hardwoods and bamboo were studied in the lab and process scale studies were also conducted. With addition of combination of surfactant DA-1 and AQ, the AA charge to maintain the constant kappa number reduced by 7.6<37>, pulping rejects reduced by 30<37> and the DCM extractives reduced by 20<37>. The yield increase was 1.5<37> over the control. The combination program resulted in higher kappa reductions (3.4 points) (cooking at the same chemical charge) when compared to use of either surfactant or AQ alone. Pulps produced with pulping additives showed higher unbleached and bleached viscosity and better bleaching response as compared to the referernce pulps. The reduction in AA and increase in yield reduced both the organic and inorganic solids loading in recovery per tonne of pulp production. In process scale trial, about 8.2<37> reduction in AA was obtained besides 23<37> reduction in knotter rejects.

11 tables, 12 ref

004290   Anuradha V J;Singh M P;Thapliyal B P;Mathur R M;Kulkarni A G (NO, Central Pulp and Paper Research Institute, P.O. Box 174, Saharanpur-247 001) : Trobleshooting of the Kraft recovery system using modern analytical tool. IPPTA Jl 2005, 17(2), 97-101.

With the closure of the recovery cycle, the presence of non-process elements in black liquors have assumed greater significance. Elements that were relatively benign have became potential source of deposit formation and corrosion in partially or completely closed cycles. Na₂ SO₄ Na₂ SO₃,Na₂,S₂O₃ and oxalates in black liquors contribute to the build-up of dead load in the recovery boilers and lead to deposit problems in the digesters and evaporators while chlorides lower the smelting temperature and cause corrosion problems. It is therefore necessary to incorporate a rapid process-monitoring tool for the analysis of such ions that are detrimental to the recovery operations. Literature has long demonstrated the use of Ion Chromatography for the speedy analysis of Kraft black liquor anions. Despite the several advantages like simplicity of operation, speed and selectivity of analysis offered by ion chromatography, the technique has not been adopted as routine method of analysis. Ion Chromatographic analysis of Kraft black liquor anions was carried out to gain insight into the practical aspects of the technique and to establish it as an alternative to conventional wet chemical analysis that is cumbersome and time consuming. It incorporates the optimization studies carried out for the analysis of Kraft black liquor and the drawbacks associated with the ion chromatographic technique.

5 illus, 4 tables, 5 ref

003226   Khare R N (Dep of Civil Engng, BIT, Durg, Chhattisgarh-491 001, Email: rn_khare@rediffmail.com) : Application of geotextiles. Res Link 2005, 4(21), 134-5.

Deals with Maintenance of the qualify system according to the ISO 9001:2000. Stringent quality standards are required to maintain during all stages of the manufacture of woven Geotextiles. The in-house test facility is required for testing the various physical, mechanical and hydraulic characteristics of the geotextiles in accordance with the relevant ASTM and IS standards. Therefore, all products are subjected to quality control tests on a regular basis. Geotextiles are permeable fabrics used in a wide range of Civil Engineering applications to perform various functions like separation, filtration, drainage, reinforcement and protection etc.

2 illus, 8 ref

003225   Alamgir Kabir M;Huque M M;Rabiul Islam M (Dep of Chem, Jahangirnagar Univ, Savar, Dhaka, Bangladesh) : Modification of jute fibre by bifunctional diazonium salts in the presence of various mordants. Biosci Biotechnol Res Asia 2004, 2(2), 79-84.

Jute Fibre was treated with bifunctional diazonium salts under the influence of some mordants (copper sulphate, nickel sulphate, potassium dichromate and potassium permanganate) in acidic and basic media. The formation of complex in the polymer system (complexed fibre) has been observed by the infrared spectra and nitrogen content estimation. The physico-mechanical properties, viz. tensile strength, tenacity, elongation at break, moisture regain, shrinkage and loss in weight of jute fibre has been studied. The tensile strength, tenacity, elongation at break and moisture regain properties of the treated (dyed) fibre are found lower in comparison with those of raw (control) fibre. However, higher tensile strength and tenacity of the complexation fibre in comparison to diazonium salts treated fibre are observed. The dyed fibre in basic media shows higher fibre strength as compared to the fibre which dyed in acidic media. The nature of the shades developed on jute fibre is also reported.

4 tables, 19 ref

002131   Venugopal S;Sivaprasad P V;Mannan S L (Metallurgy and Mater Grp, Indira Gandhi Cent for Atom Res, Kalpakkam-603 102, Email: venu@igcar.ernet.in) : Optimisation of workability and control of microstructure during deformation processing of various grades of austenitic stainless steels. Trans Indian Inst Metals 2005, 58(1), 1-17.

The paper discusses the "safe" processing windows for austenitic stainless steels type AISI 304L, 316L, 304 and a 15Cr-15Ni-2.3Mo-titanium modified steel in the temperature range of 600°C to 1200°C and strain-rate range of 0.001 s^-1 to 100 s^-1. The processing microstructure property relationships during hot working of these steels are established. The technique adopted for the study of constitutive behaviour is through establishing processing maps and instability maps, and interpreting them on the basis of dynamic materials model (DMM). The "safe" processes such as dynamic recrystallisation (DRX) and dynamic recovery (DRY) that constitute processing window are identified for above-mentioned materials. In certain regimes of temperature and strain rate, these austenitic stainless steels exhibited flow localisation and these "unsafe" domains need to be avoided during mechanical working. These predictions based on the processing maps are further validated employing large-scale experiments using rolling, forging and extrusion processes. The "safe" processing regime predicted by processing maps has been further refined using the values of apparent activation energy during deformation. The validity and the merit of this refining procedure have been demonstrated with an example of press forging trials on stainless steel 316L. The paper also discusses a model for microstructural evolution during hot working and the model has been validated for achieving a desired final grain size in extrusion by optimising the ram velocity, temperature and die profile.

^iia15 illus, 2 tables, 34 ref

002130   Tripathy A K;Misra V N (Regional Res Lab, , Bhubaneswar-751 013) : Statistical design of experiments in briquette making of steel plant waste. Trans Indian Inst Metals 2005, 58(1), 109-14.

With changing environmental regulations, land-fill costs are increasing and sinter plants are becoming more difficult to operate within a newly established emission control standard. Alternate ways must be developed to dispose of, or recover, the valuable iron contained in the revert materials generated in the steel and iron making process. These materials are flue dust, mill scale, iron ore fines and coke breeze, etc. Technologies have been developed to recover these materials. One of these technologies is cold briquetting. Hence, R&D studies have been undertaken to develop a suitable binder combination for producing briquettes from these wastes which can be charged into the blast furnace. The purpose of the present study is to determine the influence of the briquetting parameters on the quality of the product by means of experiments with a factorial design. A series of tests were carried out with different types of inorganic binders to determine their effects on briquette quality. In the study, a full, two-level factorial experimental design was used to investigate the effect of three variables on the failure load of briquettes : amount of binder, briquetting pressure and amount of water addition. For three factors, the number of experiments required was 8 excluding replicates. A multi-linear mathematical model was successfully developed to predict the failure loaded briquettes with correlation coefficient 'F' <62> 0.05 (where F = Fisher's coefficient). Abrasion tests established that the briquettes produced were sufficiently strong for handling outside storage and transportation. This was done in a rotating cylindrical drum containing four lifters which was used to determine abrasion indices of briquettes. Experimental evidence and mathematical analysis showed that the briquetting pressure and the amount of binder had marked effect on the strength of the briquettes.

6 tables, 7 ref

002129   Srivastava V C;Schneider A;Uhlenwinkel V;Ojha S N (Metal Extraction & Forming Div, Natn Metall Lab, Jamshedpur, Email: vcsrivas@yahoo.com) : Microstructural characteristics of spray formed Al-SiC_p composites. Trans Indian Inst Metals 2005, 58(1), 91-102.

Aluminium alloy (AA2014) based metal matrix composites were produced by spray atomization and co-deposition process. Various sizes of SiC_p (6 to 58 μm) were used as reinforcement with different volume fractions. Microstructures of deposits as well as overspray powder particles were examined. Porosity and SiC_p content were measured at different positions in the sprayed billet. An increase in the incorporated SiC_p volume fraction leads to an increase in the porosity. The SiC_p volume fraction showed its nearly uniform distribution along the billet radius. The microstructure of composites showed a uniform distribution of particles. The grain size decreases with increase in the volume fraction of reinforcement particulates and is sensitive to the paniculate size. Microstructural examination of overspray powder particles shows that the basic mechanism for the incorporation of smaller particles is the collision between reinforcement particles and the liquid droplets during flight. Numerical calculations, based on interfacial energy balance, showed that the large size particle can be easily incorporated but smaller ones require a high relative velocity to penetrate into the droplet.

1 illus, 11 tables, 21 ref

002128   Shaikh H;Poonguzhali A;Khatak H S (Corros Sci and Technol Div, Indira Gandhi Cent for Atom Res, Kalpakkam-603 102, Email: hasan@igcar.ernet.in) : Analysis of fatigue failures in a pharmaceutical plant. Trans Indian Inst Metals 2005, 58(1), 71-8.

A pharmaceutical plant experienced fatigue failures in two of its comonents. In one of the reactors, where two fluids were mixed, a thermowell failed because of fatigue loading caused by reverse bending. The stresses were imparted onto the freely suspended thermowell because of the violent stirring of the fluid. Amongst the recommendation suggested was change in design of suspension of the thermowell. In another failure, a bolt used to lock the fluid coupling fitted on a vertically mounted 15 hp, 1440 rpm motor, which drives the centrifuge through belt drive, gave way during operation in a pharmaceutical plant. The failure occurred due to torsional fatigue with rotary bending stresses being superimposed. Fractographic evidences suggested low nominal stresses on the bolt but high stress concentration. To avoid/delay future failures, it was recommended that high strength steel, preferably with case hardening, be used as the bolt material for this application.

13 illus, 1 table, 2 ref

002127   Selvan K;Swaminathan K;Rasappan K;Rajendran R;Michael A;Pattabi S (Biotechnology Dep, PSG Coll of Arts and Sci, Coimbatore-641 014) : Deinking of waste papers by white rot fungi Fomes luvidus, Thelephora sp. and Trametes versicolor. Nat Envir Pollut Technol 2005, 4(3), 399-404.

White rot fungi Fomes lividus, Thelephora sp. and Trametes versicolor were collected from Western Ghats area Tamil Nadu, and studied for deinking with respect to kappa number and brightness of paper produced. The isolates and their enzymes such as lignin peroxidase (LiP), manganese dependent peroxidase (MnP), laccase and mixture of these enzymes were used for the deinking of waste papers (ink papers, photocopy paper). In ink paper treatment with F. lividus and T. versicolor the maximum reduction in the kappa number was 66.7%, and increase in brightness was 45.1% (Thelephora sp.). In photocopy paper treatment, kappa number was reduced to 55.6% in Thelephora sp. and T. versicolor, while white brightness was increased to 75.8% with F. lividus after 5 days. In newspaper, the kappa number was reduced to the maximum of 66% in T. versicolor, and brightness was increased to 17.2% with F. lividus. When enzymes were employed for deinking of ink paper with T. versicolor kappa number was reduced to 75% and brightness was increased to 14.6% in mixture of these enzymes (LiP, MnP and laccase). In phtocopy paper treatment with T. versicolor laccase treatment was more than other enzymes. Overall, laccase of three fungi was more effective than other enzymes.

1 illus, 2 tables, 16 ref

002126   Selvakumar N;Narayanasamy R (Dept of Mechanical Engg, Mepco Schlenk Engg. college, Virudhunagar-626 005, Email: narayan@nitt.edu) : Deformation behaviour of cold upset forged aluminium-iron cylinders. Trans Indian Inst Metals 2005, 58(1), 19-28.

Cold upsetting experiments were carried out on sintered aluminium-iron preforms in order to evaluate their deformation characteristics. The effects of iron content and initial fractional density of the preforms, deformation behaviour have been investigated thoroughly by using graphite as lubricant. Cylindrical preforms of aspect ratio 0.75, with different initial theoretical densities were prepared using a suitable die and punch assembly. In general, each compact was subject to compressive loading in steps of 0.005 MN until fine cracks appeared on its free surface. Analysis of the experimental data has shown that the exponential law relationship between fractional theoretical density (ρ_f/ρ_th) and (ε_z-ε_θ) has been established. This remained valid for 0-8 percent iron content and all initial preform densities. Further it was found that the preforms of higher iron content show higher poission's ratio than preforms with less or no iron.

6 illus, 1 table, 19 ref

002125   Sahu A K;Biswal S K;Reddy P S R;Parida A; Misra V N (Regional Res Lab, , Bhubaneswar-751 013, Email: aksahu@rrlbhu.res.in) : A study on dynamic stability of medium in air dense medium fluidised bed separator. Trans Indian Inst Metals 2005, 58(1), 103-7.

The air dense medium separation uses a dense fluidised medium of air and fine magnetite particles for beneficiation of any material. Depending on the differences in the density of heavier and lighter solids with respect to the density of the medium, separation takes place. For dry separation, creating and sustaining the air dense medium is a complex process which requires intensive investigation. The dynamic stability of the medium plays the important role in the sharpness of the separation and the system operates under particulate fluidisation system. The different geometrical dimension of laboratory models were fabricated for this study. The magnetite powder below 45-micron size was used as solid medium. The compressed air at different airflow rate was used as fluid medium. Dense medium was created by suspending solid particles in an upward direction of flow of air. The study on dynamic stability of medium was determined by the values of the following physical parameters i.e., harmonic mean diameter of particles size distribution, true and bulk density of magnetite powder, porosity of the bed, pressure drops at the air distributor and bed density of the fluidised bed. Based on experimental data, four dimensionless groups i.e., Froude number, Reynolds number, ratio of density of fluid and solids and aspect ratio of the system are used to characterise the quality of fluidisation.

7 illus, 4 tables, 5 ref

002124   Rao G V S N;Rao M H;Rao G S (Dep of Metall and Mater Engng, Natn Inst of Technol, Warangal-506 004, Email: gvsnr@nitw.ernet.in) : Influence of fluidized bed nitrocarburising on tribological and mechanical properties of En-8, En-19 and En-24 steels. Trans Indian Inst Metals 2005, 58(1), 79-89.

The case characteristics of the fluidized bed nitrocarburised En-8, En-19 and En-24 steels, in an atmosphere of ammonia, air and LP gas, have been examined by metallography and X-ray diffraction. The nature of the compound layer and the structure of the diffusion zone are observed to be dependent on atmospheric composition and mode of cooling respectively. Specimens quenched in oil after ferritic nitrocarburising showed higher fatigue strength compared to air-cooled specimens. Substantial improvement in the wear resistance has been observed after ferritic nitrocarburising. Better case characteristics are obtained in ferritic nitrocarburised specimens with respect to microhardness, fatigue strength, wear resistance and corrosion resistance.

11 illus, 3 tables, 14 ref

002123   Goel a;Mishra A (Govind Ballabh Pant Univ of Agric and Technol, , Pantnagar-263 145) : Physical properties of woollen fibres of Uttaranchal. Indian Fmg 2004, 54(1), 5-8.

Wool fibres and Angora hair possess good physical properties, which are compatible for blending. Good quality apparel can be prepared from the yarn obtained after blending of Angora hair and Merino wool fibre. Nepali and Rambouillet wool fibres can also be blended together to prepare sweaters, mufflers or other knitted items. Quality of the end products is dependent on physical properties of fibre used. Therefore, knowledge about these properties will help people to decide right combination of blend, which in turn, will increase the utility of the wool available in Uttaranchal.

9 illus, 1 table

002122   Ghosh P K;Balaram M (Dep of Metall & Mater Engng, Indian Inst of Technol Roorkee, Roorkee-247 667, Email: pkgfmt@iitr.ernet.in) : Improvement in spot weld properties of steel sheet by weldbonding using particulate composite adhesive. Trans Indian Inst Metals 2005, 58(1), 115-31.

Lap joints of 1.0 mm thick structural steel sheet were prepared by adhesive bonding, conventional resistance spot welding and weldbonding processes. The adhesive bonding and weldbonding were prepared by using the conventional adhesive and two types of composite adhesives reinforced with different amount of Al and Al₂O₃ particles. Adhesive lap joining of two pieces of mechanically polished surface of the substrate followed by resistance spot welding gave rise to weldbonding and final curing at 120°C for 60 minutes. The bond line thickness of all types of adhesive layers resulting maximum shear-tensile strength of the joint was optimised. The size of weld nugget, infrastructures of the weld and HAZ and hardness of the nugget and HAZ, resulted from different welding parameters (current and time), in both the resistance spot-welds and weldbonds were studied. The ultimate shear-tensile load bearing capacity of the resistance spot-welds and weldbonds are also compared and correlated with the welding parameters. The fatigue properties of the resistance spot weld and weldbond, having maximum strength, were also tested. The fracture behaviour of all the three types of joints was studied under optical stereomicroscope. The weldbonds prepared at optimum process parameters were found to have superior mechanical properties than those of the conventional resistance spot welds, especially under dynamic loading. The suitability of metallic or non-metallic particulate reinforcement of adhesive in preparation of weldbonding has been analysed with respect to their affinity of interaction with gases and electrical charging behaviour respectively during welding.

23 illus, 2 tables, 25 ref

002121   Chatterjee S;Pal T K (Res Scholar Weld Technol Cent, Metall Engng Dep Jadavpur Univ, Kolkata-700 032, Email: t_k_pal@yahoo.com) : Study on microstructure and abrasive wear of hardfacing deposits on cast iron. Trans Indian Inst Metals 2005, 58(1), 49-60.

Microstructures of Fe-Cr-C base hardfacing deposits with varying percentage of carbon and chromium as well as addition of niobium and molybdenum deposited on gray cast iron under different welding procedure were studied and abrasive wear behaviour of those deposits was evaluated using the dry sand rubber wheel abrasion test. Welding procedure exerts significant variation on deposit chemistry and hence microstructure particularly volume fraction of carbides. Again, volume fraction of carbide is also dependent on Cr/C ratio. For a given chromium and carbon content, addition of niobium and molybdenum further modified the microstructure. Abrasive wear resistance of Fe - Cr - C based hardfacing deposits is found to improve with increase in volume fraction of carbides upto a certain value (^<126>35%), and further improvement is obtained by refining the carbides as well as strengthening the matrix with the addition of Nb and Mo.

8 illus, 4 tables, 16 ref

002120   Bhide k;Dhokey N B (Dep of Metall Engng, Pune Inst of Engng and Technol, Pune-411 005, Email: nbdhokey@yahoo.co.in ) : In-situ Cr₂Nb precipitation in copper alloys by a powder metallurgy route. Trans Indian Inst Metals 2005, 58(1), 137-40.

The attempt was made to manufacture copper alloy containing 6.52%Cr and 5.81 % Mb (by wt) by a powder metallurgy route. The decomposition temperature of Cr₂Nb precipitate is 1770°C. and therefore the presence of such precipitates enhances the stability and mechanical properties of copper alloys at elevated temperatures. This alloy has been found useful in aerospace applications. The fine powders of copper, chromium, aluminum and niobium pentaoxide were blended in specially designed powder blending set-up. The blended powders were cold compacted to make compacts of 10mm diameter and 10mm height and then sintered in argon atmosphere in tubular silicon carbide heating furnace at 900°C for 2 hours. The thermodynamic calculation was done to calculate adiabatic temperature developed during sintering. Similarly free energy calculation indicated the spontaneity of the reaction. Microstral analysis and XRD analysis confirmed the presence of Cr2Nb precipitate in the sintered copper matrix.

4 illus, 1 table, 9 ref

002119   Bhargava A K;Tiwari A N (Dep of Metall Engng, Malaviya Natn Inst of Technol, Jaipur-302 017, Email: akmt@rediffmail.com) : Some microstructural aspects of melt-spum D2 steel. Trans Indian Inst Metals 2005, 58(1), 41-7.

Commercial D2 steel has been rapidly solidified using melt spinning technique. Effect of substrate velocity (V_s) on ribbon thickness (t) has been examined and found to follow the empirical relationship t = K V_s^-b. Microstructure of melt-spun ribbons was examined along the length and width across the thickness of the ribbon. The morphological features have been observed to vary from cellular to dendritic depending upon the cooling rate which in turn varies from melt-wheel contact surface to air side surface of the ribbons. TEM study of the as-spun ribbon sample revealed M₇C₃ type carbide in the interdendritic region of metastable austenite.

6 illus, 21 ref

002118   Bhakat C;Sahani M S (Natn Res Cent on Camel, , Jorbeer, PB 07, Bikaner-334 001) : Pattern of utilization and potentiality of camel skin. Indian Fmg 2004, 52(2), 3-5, 23.

Today camel skin are utilized for preparation of a variety of consumer goods in few regions of Rajasthan (Jaisalmer, Barmer) and Gujarat but in olden days camel hide were popularly utilized for storing ghee and oil under village conditions. Skin of young calves are useful for making fur and those of adults for leather. The epidermis of camelid is usually composed of stratum corneum, s. lucidum, s. granulosum, s. spinosum and s. germinativum. The dermis consist of superficial layer, mid-dermis and hypodermis. Flaying of camel hides is generally done manually to get raw hide which are mostly cured by air-drying. The semi-dried camel calf skins have to pass through some chemical and mechanical treatments before they get actually converted into a fur, viz. soaking, removal of flesh, pickling, tanning, fatliquored and finally washed and dried. Additional operations in making leather are treatments of cured camel hides with liming process, bating process, dyeing and lacquer finishing. There is a great potentiality of utilization of camel skin as furs. The cost of small article varies from Rs 500 to Rs 3 000, whereas the cost of big item varies from Rs 10 000 to Rs 12 000. Attention has also been paid to explore the possibilities for modern use with the help of newer technology, in addition to the traditional uses too.

4 illus

002117   Basu J;dey G K;Banerjee S;Ranganathan S (Dep of Metallurgy, Indian Inst of Sci, Bangalore-560 012, Email: surya@platinum.met.iisc.ernet.in) : Phase evolution in quaternary Zr-Cu-Ni-Al and quinary Zr-Cu-Ni-Al-Pd bulk metallic glass forming alloys. Trans Indian Inst Metals 2005, 58(1), 61-70.

Inhomogeneous deformation tendency and the unhindered flow of shear bands in bulk metallic glasses, leading to catastrophic failure, can be mitigated by partial crystallisation or reinforcement by second phase particles in the amorphous matrix. Quaternary Zr₅₅Al₁₀Ni₅Cu₃₀ and quinary Zr₆₀Al₁₀Ni₁₀Cu₁₅Pd₅ alloys have been cast in a copper mould in the form of 3 mm diameter rods. Though the alloys are multicomponent in nature with widely different atomic size of the constituent elements and with high negative heat of mixing, a change in the processing conditions results in partial crystallisation of the alloys while casting. cF96 NiZr₂ and oC68 (Cu, Ni)₁₀Zr₇ phases are observed after casting and crystallisation. The nature of the crystallising phases indicates that polytetrahedral units exist in the amorphous alloys, which can be explained in terms of Bernal deltahedra and Frank-Kasper polyhedra. Pseudo-ternary composition plot of the alloys indicates that the alloy compositions are very close to the anti-Laves composition in the relevant system. The phase evolution in the alloys has been explained in terms of enthalpy of mixing, atomic radii mismatch and the structure of the crystalline phases.

10 illus, 1 table, 28 ref

001022   Tarafder N;Sett S K;Das A (NO, Govt College of Engg & Textile Technology, Serampore, 12, William Carey Road, Serampore, Hooghly-712 201) : Experimental study on water repellent plain woven umbrella cloth. II. Man Made Text India 2005, 48(2), 69-74.

6 tables, 22 ref