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Abstract: Vacuum Arc Degassing (VAD) ladle covers are a vital item for steel production through VAD units. Under prevailing operating conditions of VAD, ladle cover refractories need to sustain high thermal shock and a corrosive environment. Their operational conditions and lining patterns also demand a high volume stability of the refractory material. A composition of a high alumina castable suitable for the manufacture of pre-cast blocks was designed to obtain the desired properties. It was found that castables with an optimum amount of Cr2O3 in combination with the proper deflocculant and dispersing agents were the most suitable. Based on the study, pre-cast blocks were manufactured with the castable developed and tried in VAD ladle covers of ASP, SAIL. It was observed that pre-cast blocks of VAD ladle covers were highly stable under the severe VAD operating conditions and have the potential to result in a good lining life. [ABSTRACT FROM AUTHOR]

Abstract: 60 % Al2O3-based high alumina bricks are used in different areas of steel plants. In the Rourkela Steel plant, these bricks are used in the working lining of reheating furnaces and sinter plant furnaces. The primary requirement of the refractory is high thermal shock resistance in these areas. A laboratory investigation was carried out to study the influence of andalusite on the thermo-mechanical properties of 60 % Al2O3-based bricks. The effects of the amount of andalusite on the phase composition and microstructure of the refractory were investigated by XRD and FESEM. The results revealed that a higher percentage of andalusite provides better physical properties because of the higher mullite content in it. Phase analysis by XRD and microstructure analysis by FESEM proved the presence of mullite as major phase in the end product. [ABSTRACT FROM AUTHOR]

Abstract: Reheating furnaces are used in steel plants for the heating of billets, blooms and slabs. Sometimes steel plants opt for a more costly/higher grade refractory in the preheating-zone hearth of the furnace to match the hearth life with other zones of the furnace. Keywords: high-alumina brick, reheating furnace, preheating-zone hearth brick The cost of these developed bricks is also much lower as compared to the existing refractory being used for the lining of the preheating-zone hearth of the reheating furnace at Merchant Mill. [Extracted from the article]

Plastic refractory properties were studied by synthesizing two different binders in the laboratory. Liquid phosphate binders from different sources, a sol-gel bonding system, organic plasticizers, water retention agent and deflocculating agent were optimally mixed using different techniques for binder synthesis. The stability of the thixotropic behaviour of the binders varied with different compositions and techniques. Plastic refractory products were manufactured in the laboratory with an identical raw material composition and particle size distribution. Plastic refractory products with different binders were characterized based on the workability index of green mass, bulk density, cold crushing strength, modulus of rupture and permanent linear change of fired samples at 850 °C and 1200 °C. Phase and micro-structure analysis was in line with the thermo-mechanical properties of end products. The plastic refractory prepared with Binder B-1 was found to be optimal in terms of workability and thermo-mechanical properties. [ABSTRACT FROM AUTHOR]

Abstract: Genetic relatedness was estimated among 30 genotypes of two populations of Mystus cavasius i.e., Gandhisagar reservoir (n =15) and Bansagar reservoir (n =15) using 5 random amplified polymorphic DNA (RAPD-PCR) markers. Ten primers were primarily scored of which, 05 primers showed polymorphism and these were selected for polymerase chain reaction (PCR) to be used in the final molecular analyses. 64 scorable loci were generated in genotypes from Gandhisagar reservoir of which 62 loci (70.45%) were polymorphic; whereas, 108 loci were obtained in genotypes from Bansagar reservoir out of which 87 (98.86%) were polymorphic. RAPD analysis showed that the Bansagar reservoir population had higher genetic polymorphism than the Gandhisagar reservoir population. Analysis of Molecular Variance (AMOVA) indicated low genetic diversity (Hpop=0.2017±0.1836; I =0.312±0.2599) and relative genetic differentiation among the populations (Gst=0.2052) and restricted gene flow (N m =1.9369). The phylogenetic tree constructed by un-weighted pair-group method of analysis (UPGMA) showed that all genotypes formed two major clusters representing their respective geographical locations i.e., Gandhisagar reservoir population and Bansagar reservoir population. Present investigation elucidates effectiveness of balancing approaches to make polymorphism as descriptive and determined for optimum genetic amelioration and successful conservation of its genotypic variability. This study also showed high levels of morphometric and genetic variation in Bansagar reservoir population indicated dynamic evolution as revealed by genetic variations in genotypes. [Copyright &y& Elsevier]

Investigations were carried out at seven underground coal mines in India to characterise the responses of roof and pillars of underground workings to the vibrations induced by adjacent open-pit blasting. The roof rocks of the selected underground instrumented panels were having RMR between 36.7 to 57. Monitoring of strata behaviour was carried out before and after blasts. Arrangements were made to mount the transducers of seismographs in roof and pillars to monitor the vibration. Attempts were made to monitor the vibration simultaneously, for a blast, in the pillar and at the junction of the roof or away from the junction in the gallery. 102 sets of such vibration data were recorded in the underground mines. It was observed that the roof of underground roadways vibrated with higher peak particle velocity (PPV) compared to pillars. The amplification of vibration in the roof compared to pillars, away from the junction, was 1.02 to 2.58 times whereas at the junctions, it was 2.04 to 5.57 times. [ABSTRACT FROM AUTHOR]

At present, testing for distinctness, uniformity and stability (DUS) of crop varieties relies on a set of morphological characters. These characters suffer from the limitations of number, interaction with the environment in which the variety grows and subjectivity in decision-making. The potential of DNA-based markers such as sequence tagged microsatellite site (STMS), for establishing DUS merits investigation. In the present study, a set of 55 mapped STMS markers, selected from 12 linkage groups of rice genome, was used to examine distinctness of 23 aromatic rice genotypes including the commercially important Basmati varieties. Forty-one of these markers (74.5%) showed polymorphism between the varieties. The number of alleles per locus ranged from 2–4 with an average of 2.3. The polymorphism information content (PIC) of the markers varied from 0.083 to 0.665 with an average of 0.338. All the varieties could be differentiated from each other at a low probability (0.07×10-13) of identical match by chance. The marker-based clustering of the varieties corresponded with the known phenotypic classification, thereby providing confidence in the distinctness established by the mapped STMS markers. The utility of these markers to study uniformity and stability was analysed using a commercially important crossbred Basmati rice variety Pusa Basmati 1 (IET-10364) that contributes about 40–50% of Basmati rice export from India. Genotyping of twenty individual plants, grown from the nucleus, breeder, foundation, certified and farmer's saved seed samples using all the 55 markers revealed no variation among the plants. These observations suggested that the set of mapped markers employed in this study could be further used for establishing distinctness of aromatic rice varieties and for studying DUS of the important commercial variety Pusa Basmati 1. [ABSTRACT FROM AUTHOR]

Segregation for salinity tolerance and ISSR markers based molecular polymorphism were investigated in a F3 plant population raised via single-seed descent method from a cross between salt-tolerant indica rice variety CSR10 and salt-susceptible premium traditional Basmati rice variety Taraori Basmati HBC19. A total of 130 F3 plants were evaluated individually for salinity tolerance on 1–9 scale on the basis of seedling growth parameters; the average score ranged between 1.7 to 8.3. Frequency distribution curve obtained using the salinity tolerance data of F3 population and a chi-square analysis, showed a good fit to a normal distribution. Eleven plants each in the category of salt-tolerant and salt-susceptible were selected from the segregating F3 population for ISSR marker analysis. A total of 149 bands (4–11 bands per primer) ranging from 200 to 3530 bp were scored for the two rice varieties and the selected CSR10 × HBC19 segregating F3 plants using 26 ISSR primers. Of these, 89 were monomorphic and 60 were polymorphic. Of the 60 polymorphic bands, 36 and 20 bands were specific to CSR10 and HBC19 respectively. The remaining four bands were amplified using UBC primers 810, 848, 853 and 886 and present in only some of the CSR10 × HBC19 F3 plants. Notably, ISSR primers with dinucleotide repeat motif and 5'-anchored end amplified more number of bands (7.0 bands/primer) compared to 3'-anchored dinucleotide primers (5.4 bands/primer), but 3'-anchored dinucleotide primers revealed higher level of polymorphism (2.6 polymorphic bands/ primer) compared to 5'-anchored dinucleotide primers (1.43 polymorphic bands/ primer). While distribution of majority of the polymorphic bands were more or less in the expected ratios in salt-tolerant and/or salt-sensitive F3 segregating plants, but some of the bands amplified using UBC ISSR primers 823, 825, 826, 849, 853, 864, 866 and 884 showed highly skewed distribution. Such polymorphic bands stand greater chances of having a linkage with the genes/ QTLs for salinity tolerance and shall be the target for further studies. [ABSTRACT FROM AUTHOR]

A panel of 38 monoclonal antibodies (MAbs) that react with outer membrane proteins (OMPs) of Salmonella enteritidis was produced. On the basis of their binding pattern in ELISA, the MAbs were divided into three groups. The first group, consisting of 15 MAbs, was found to be Salmonella-specific as they did not cross-react with Escherichia coli or Pasteurella multocida. The second group of 15 MAbs cross-reacted with E. coli but not with P. multocida, reflecting the closer antigenic relationship of E. coli with Salmonella. The third group of 8 MAbs cross-reacted with both E. coli and P. multocida, indicating that the antigenic determinants identified by these MAbs are conserved in all the three genera. The antigenic relationship of the Salmonella serovars ( S. enteritidis, S. gallinarum, S. typhimurium, S. dublin, S. agona, S. indiana and S. choleraesuis) was studied using OMPs prepared from them and the anti- S. enteritidis MAbs. Three MAbs appeared to be specific for S. enteritidis as they did not cross-react with any of the other Salmonella serovars. Twelve of the 38 MAbs cross-reacted with all the serovars tested. Six of these were specific to the Salmonella genus as they did not cross-react with any of the other Gram-negative bacteria tested. The reactivity pattern of the other MAbs indicated that S. gallinarum was antigenically close to S. enteritidis, followed in order by S. dublin, S. agona, S. typhimurium and S. indiana, whereas S. choleraesuis seemed to be antigenically quite distant from S. enteritidis. [ABSTRACT FROM AUTHOR]

A number of breeding institutions developed a project to assess importance of participatory plant breeding approaches for rainfed rice improvement in eastern India. The results of the first two years of participatory varietal selection are reported here. The objective was to evaluate the respective effects of participation of farmers in varietal evaluation and decentralization of varietal testing from breeding stations to farmers' fields on varietal ranking. Fields representing various hydrological situations were chosen in two to three villages at four rainfed lowland sites and one upland site. Sets of 15 to 25 varieties were tested both in farmers' fields and on-station in 1997 and 1998 and ranked by both farmers and breeders. The effect of participation was judged by comparing the rankings attributed by farmers and breeders to a given set of material in a given trial. The effect of decentralization was determined through comparisons between individual breeders' rankings across trials. Farmers' rankings were not randomly allocated, but agreement within the farmers' group was not always very strong. Except at one site, concordance among breeders' ranking was high, but, because of the limited number of breeders involved, it was seldom significant. In about two-thirds of the trials, there was a good agreement between farmers' and breeders' mean rankings. The consensus was particularly strong when severe constraints induced contrasting behavior in the genotypes. The decentralization effect appeared to be moderate, but variations due to a breeder effect were recorded. The part of genotype by environment interactions for grain yield due to location within one site and year was evaluated through various methods, showing more effect of G × E interactions at some sites than at others. Crossover interactions inducing changes in ranks represented a limited part of the yearly G × E interactions at all sites. Both farmer participation and decentralization of varietal testing in farmers' field would help in best matching the varieties to the needs, although their combined contribution would be more useful in some sites than in others. [ABSTRACT FROM AUTHOR]

A simple method for the rapid detection of rabies virus was developed employing a single-tube reverse transcription–polymerase chain reaction (RT-PCR). The method utilized a single buffer system for both RT and PCR and was performed without interruption as a single thermal cycling programme. Two primer sets within the genes coding for rabies nucleoprotein and glycoprotein were used to amplify a 533 bp and a 406 bp amplicon, respectively. The amplified products were detected with a challenge virus strain (CVS) of rabies. There was no amplified product with uninfected mouse or dog brain. The method was applied to detect rabies virus in 10 mouse inoculation test (MIT)-positive and three MIT-negative brain tissue samples. The amplified product was found only in the MIT-positive samples. The amplified product was confirmed by restriction endonuclease analysis using Hinf1. The results from RT-PCR correlated well with the results from MIT. This indicates that the single-tube RT-PCR may be a useful method for detecting rabies virus in brain tissue samples from suspected cases of rabies. [ABSTRACT FROM AUTHOR]

Diamond coatings on porous silicon (PS) samples have been obtained by the hot-filament chemical vapor deposition(CVD) technique. We focused our attention on the coating morphology, showing experimentally that high quality diamond coatings may be produced with the PS sample kept at 710°C. The deposited patterns consist of polycrystalline grains with a plane interface with the PS layer.At 790°C, the quality of the coating is improved but the PS layer becomes damaged, and at 650°C the coating consists of diamond-like carbon particles. Besides the temperature, other factors such as the porosity, roughness and chemical activity of the PS layer deserve attention. We observed that one of the limiting factors of the deposition process was the high nucleation time. Two nucleation mechanisms are involved in the growth process. The first nucleation mechanism occurs on the top of the sharp PS features, subsequently to the nucleation a superficial film, and then a second nucleation mechanism occurs over this surface, which allows the growth process to continue. We also observed the presence of ablue-shift in the luminescence spectra following the coating. [ABSTRACT FROM AUTHOR]

The total genomic DNAs from Trypanosoma evansi isolates of bubaline, equine and cameline origin were amplified by polymerase chain reaction using eight arbitrarily selected 10-base primers. Informative band patterns were obtained for all isolates analysed. Depending upon the T. evansi isolate–primer combination, between 1 and 11 reproducible DNA fingerprints of 205 to 3016 bp were amplified, suggesting minor and major differences in their RAPD (random amplified polymorphic DNA) profiles. [ABSTRACT FROM AUTHOR]

Abstract. The microstructure and properties of barium strontium titanate (BST) thin films grown by an in situ ultraviolet-assisted (UV-assisted) pulsed laser deposition (UVPLD) technique are reported in this paper. In comparison with BST films grown by conventional pulsed laser deposition (PLD) under similar conditions, but without UV illumination, the UVPLD-grown films exhibited improved structural, electrical, and optical properties. X-ray photoelectron spectroscopy showed that when exposed to atmosphere, Ba atoms from the outermost layers formed a thin layer of barium carbonate, which negatively affects the film electrical characteristics. UVPLD-grown films exhibited a smaller amount of Ba atoms within the carbonate layer, resulting in better electrical characteristics. The dielectric constant of 40-nm-thick films deposited at 650 Celsius by UVPLD and PLD were determined to be 281 and 172, respectively. The leakage current density of the UVPLD-grown films was in the mid-10[sup -8] A/cm[sup 2] range, a factor of 2 lower than that obtained from PLD-grown films. [ABSTRACT FROM AUTHOR]

Abstract. ZnO thin films have been grown on thin Si[sub 3]N[sub 4] membranes and (001) sapphire substrates by an ultraviolet-assisted pulsed laser deposition (UVPLD) technique. The microstructure of the films grown on Si[sub3]N[sub 4] membranes, investigated by transmission electron microscopy, showed that crystalline and textured films can be grown by UVPLD at a substrate temperature of only 100 Celsius. For deposition temperatures higher than 400 Celsius, ZnO films grown on sapphire substrates were found to be epitaxial by Rutherford backscattering (RBS) and X-ray diffraction measurements. The minimum yield of channeling RBS spectra recorded from films deposited at 550 Celsius was around 2% and the FWHM of the rocking curve for the (002) diffraction peak was 0.17 Degrees; these values are similar to those recorded from ZnO layers grown by conventional PLD at 750 Celsius. [ABSTRACT FROM AUTHOR]

Abstract. Thin Y[sub 2]O[sub 3] films have been grown on (100) Si using an in-situ ultraviolet-assisted pulsed laser deposition (UVPLD) technique. When compared to conventional pulsed laser deposited (PLD) films under similar conditions, the UVPLD-grown films exhibited better structural and optical properties, especially those grown at lower substrate temperatures, from 200 Celsius to 400 Celsius. X-ray diffraction investigations showed that the films grown were highly crystalline and textured. According to X-ray photoelectron spectroscopy and Rutherford backscattering spectrometry investigations, UVPLD-grown Y[sub 2] O[sub 3] films have a better overall stoichiometry and contain less physisorbed oxygen than the conventional PLD-grown films. The refractive index values, measured in the range 300-750 nm by using variable-angle spectroscopic ellipsometry, were similar to those of a reference Y[sub 2]O[sub 3] film. [ABSTRACT FROM AUTHOR]