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Birds (433) were utilized for investigation at 7 weeks of age and at 45 weeks of age (119). The immunological traits measured included humoral response like HA, MER and MES; non-specific immune responses like CPW and APW complement and PI and CMI response. In two broiler lines, body weight at 6, 7, 8, 9 and 10 weeks of age were measured in addition to body weight at hatch and feed efficiency to 10 weeks of age. In rest of the genetic groups, the economic traits measured included day old body weight, body weight, shank length and keel length at 5, 10, 15 and 20 weeks of age, age at sexual maturity, egg production as number of eggs to 40 weeks of age, egg weight at 40 weeks of age, per cent mortality during different periods up to 20 weeks of age, feed consumption per day, and feed conversion ratio to produce a dozen of eggs or a kg of egg mass. All the traits were measured on individual birds except for per cent mortality and feed efficiency in broilers. For evaluation of humoral and nonspecific responses except PI, the birds were immunized with sheep red blood cells (SRBCS) by injecting 1 ml of 25% (v/v) SRBCs suspension in PBS intramuscularly in thigh muscle. The various components of immunocompetence parameters like humoral and nonspecific responses were measured on day 5, 12 and 19-post immunization. Natural antibodies for various immunocompetence traits were also measured on the day of SRBC injection. For evaluation of effect of age, birds of the Aseel, Kadakanath, Naked Neck and Frizzle were immunized against SRBCs at 45 weeks of age and immunocompetence traits were measured on day 0 and 7 p.i. CMI response was estimated by injecting 0.1 ml of PHA-P interdigitally (100 µg PHA-P/0.1 ml of PBS) between the 3rd and 4th toe of the right foot of each chicken as Foot index (FI) and was estimated by measuring the skin swelling. Data so collected were analyzed statistically utilizing appropriate statistical procedures to evaluate correlation coefficients among immunological and economic traits calculated as simple product moment correlation. HA was positively correlated with MER, CPW and APW and negatively correlated with FI and PI. The trend remained the same on all the days of study. The correlation of MER with CPW and APW were mostly positive and did not present any definite trend in both magnitude and direction with FI and PI. The correlations between CPW and APW were positive and highly significant. No definite trend was observed for the correlation between CPW with FI and PI. The trend remained the same for APW also. FI and PI were negatively correlated in indigenous breeds and broilers but positively correlated in Dahlem Red and White Leghorns. Irrespective of direction, all the estimates were small. HA was seen to be positively correlated with body weight, shank length, keel length, ASM and negatively correlated with egg production and mortality. MER was positively correlated with body weight, shank length, keel length and ASM and negatively correlated with egg production and mortality. The relationship of FI and PI with body weight, shank length, and keel length was negative. Relation between FI and egg production was negative. The relationship of immunocompetence traits with economic traits presented in the literature as well as realized in this study did not lead to any definite conclusion suggesting more study to quantify the magnitude and direction of relationship for their use in practical breeding programmes. [ABSTRACT FROM AUTHOR]

The article presents a drug profile of ethinyl estradiol/dienogest. Topics discussed include the bioavailability of ethinyl estradiol, the role of combined oral contraceptives (COCs) in inhibition of ovulation and effects of COCs on lipid metabolism such as increased levels of triglycerides, very low-density lipoprotein (VLDL) cholesterol and high-density lipoprotein (HDL) cholesterol.

From a sinter production point of view, it is important to optimise the sintering process with regard to both sinter quality and production rate. In sintering, airflow rate within the sinter bed decides the production rate and its physical and metallurgical properties. To study the influence of airflow rate (flame front speed) on sinter production and sinter quality, pot grate sintering experiments were conducted at sinter grate suction pressures ranging from 900 to 1700 mm water column over the sinter bed. During sintering, time-temperature data were recorded, and mineralogical studies were carried out. This study reveals that increase in sinter grate suction pressure through the sinter bed from 900 to 1700 mm water column significantly improved the sinter productivity from 34·37 to 48·90 t/m2/day; however, the physical and metallurgical properties of the sinter at higher suction pressure were not optimum with respect to blast furnace requirements. The maximum sinter productivity with desired physical and metallurgical properties was obtained at suction pressure 1300 mm water column. At this pressure, improvement in sinter quality was due to optimum firing temperature and enough retention time available for formation of mineral phases. At an airflow rate 1300 mm water column, sinter productivity was 41·0 t/m2/day, sinter strength (TI) was 73·10%, reduction degradation index was 25·0 and reducibility was 71·50%. [ABSTRACT FROM AUTHOR]

Iron ore sinter, constituting a major proportion of blast furnace burden, significantly impacts the blast furnace performance. The chemical composition of iron ore fines, particularly alumina, sinter basicity and sinter MgO together with the thermal conditions that sinter blends are subjected to play an important role in the formation of mineral phases in sinter. To increase the sinter proportion (70-80%) in blast furnace, lowering of CaO in sinter mix is a vital parameter to balance the flux supply without affecting the slag volume and productivity. At present, the alumina content in the sinter grade iron ore fines at JSW Steel varies from 4 to 6%. The quality of iron ore presently being used calls for extensive investigations to produce low basicity sinter with high alumina iron ore. Studies have been carried out on low and high alumina iron ore fines to know the influence of sinter basicity and fuel (coke breeze) addition on sinter mineralogy, properties and productivity. It is found that with increase in sinter basicity, sinter productivity and reduction degradation index (RDI) decreased and tumbler index (TI) increased for both low and high alumina sinter at coke breeze rate of 65 kg t−1 of sinter. The low alumina sinter showed higher productivity and strength, and lower RDI due to the presence of higher silico ferrites of calcium and aluminium (SFCA) and magnetite phase, and lower pore phase as compared to high alumina iron ore sinter. The sinter productivity decreased and physical and metallurgical properties improved with increase in coke breeze addition by increasing the sinter basicity for high alumina sinter. [ABSTRACT FROM AUTHOR]

The quality of iron ore sinter mainly depends on sinter mineralogy, which in turn depends on the chemical composition of the sinter mix. The reduction properties of the mineral phases formed in the sinter influences the sinter reducibility. MgO has a varying effect on sinter reducibility at different silica contents. A recent trend in blast furnace operation shows that there is a considerable increase in usage of dolomite as a basic flux either directly or through sinter. Recently the silica levels in the sinter product of Sinter plant 1(SP1) of JSW Steel Limited have been fluctuating in the range of 5·5-9·6% due to variation in silica content of iron ore fines. At the same time, as per blast furnace requirement, the addition of dolomite has been changed from 2·4 to greater than 3·0% at SP1, and the reducibility of the sinter decreased (<60·0%). Laboratory pot grate sintering experiments have been carried out to determine the influence of MgO addition on microstructure and reducibility of low and high silica sinter. MgO additions have been varied from 1·4 to 3·2% for low silica (4·5%), and high silica (6·3%) iron ore fines. From the studies it was found that the reducibility of both sinters decreased with increase in MgO addition due to an increase in magnetite/magnesio spinel phase and silicate/slag phase. Reducibility of low silica sinter was greater with high silica sinter. High silica with high MgO sinter had lower reducibility compared to low silica with low MgO/high MgO and high silica with low MgO sinter. [ABSTRACT FROM AUTHOR]

Fly ash (FA), a by-product of thermal power plants, with a pH of more than 9.0 and containing macronutrients including P, K, Ca, Mg and S and micronutrients Fe, Mn, Zn, Cu, B and Mo can be utilized to ameliorate acid lateritic soils to improve fertility and productivity. An experiment was conducted for two years commencing during 2003 to study the direct effect of FA, organic materials like farm yard manure (FYM), vermicompost (VC) and green manure (GM) and chemical fertilizers (CF) on sabai grass (Eulaliopsis binata) during wet season (rainy season) and residual effect on the same crop during dry season (rabi season) in sandy loam acid lateritic upland soil. Application of FA in combination with organic materials and CF recorded 20.2% higher yield over sole CF. Dry grass yield during dry season was also significantly higher under the residual effect of the former rather than the latter. Sabai grass yield was maximum under the direct effect of GM in combination with CF (14.2%). Uptake of N, P, K, Ca, Mg, Fe, Mn, Zn and Cu by sabai grass was significantly higher under the combined effect of CF, organic materials and CF than application of CF alone. Beneficial effect of integrated nutrient management was also apparent on residual soil fertility in terms of pH, organic carbon and available N, P and K status as compared to continuous use of only CF. [ABSTRACT FROM AUTHOR]

For better blast furnace performance, there has always been a need for better quality raw materials like sinter, lump ore, and pellets. Among these raw materials the usage of sinter in blast furnace is at higher side compared to other iron bearing materials. As the quality of sinter product improves, its usage in blast furnaces also increases. Iron ore fines are the main source for sinter making. To improve the sinter properties it is necessary to provide good quality of iron ore fines. Due to depletion of high grade iron ore resources, goethite and limonitic ore content in iron ore fines is expected to increase gradually. Usually limonitic and goethite ore are associated with higher alumina and LOI. The conventional sintering process is one of the well established processes for high quality hematite ore. It does not fully respond to the low grade iron ore associated with goethite and limonite. This has led to deterioration in sinter properties and productivity. In recent years the improvement in the quasi-particle structure with the granulation process is an effective method for improving sinter quality and productivity. To improve the sinter quality and productivity for low grade iron ore fines, different granulation processes like the conventional one, and other two advanced granulation processes like coke breeze, and flux & coke breeze coating granulation were studied in detail by conducting laboratory pot grate sintering experiments. From the test results it was found that sinter productivity, physical and metallurgical properties of the sinter improved with flux & coke breeze coating granulation process compared to conventional and coke breeze coating granulation process. Proper selection of the granulation time is very important to achieve the desired sinter properties. In the present work detailed laboratory experiments have been carried out by varying the coating time from 30s to 110s to study the influence of flux & coke breeze coating granulation time on mineralogy, productivity, physical, and metallurgical properties of sinter. With a coating granulation time of 50s, higher productivity, higher yield, and stronger sinter (higher T.I) with lower RDI and -5mm size sinter were achieved. [ABSTRACT FROM AUTHOR]

Iron ore fluxed sinter is the main ferrous burden of Jindal south west steel limited (JSWSL) blast furnaces. In sinter plant fluxes including limestone and dolomite are added to improve the sinter properties of iron ore and to provide an appropriate slag composition of the blast furnace. The raw material grain size affects the sinter process considerably because the sinter productivity and quality are strongly dependent on the green permeability of the bed, which is determined by the particle size distribution of the raw materials, the granulation effectiveness and by the sintering process itself. It is well-known that in fluxed sinter, the size of limestone affects productivity and physical and metallurgical properties of the sinter. It is therefore necessary to understand the role of limestone particle size on sinter properties and productivity. In the present work laboratory sintering experiments have been carried out with different levels of limestone mean particle size (from 0.14 to 1.83mm) to understand the influence of limestone particle size on mineralogy, productivity, physical and metallurgical properties of the sinter. Sinter productivity increased with increasing limestone mean particle size due to improved sinter bed permeability. Sinter with limestone mean particle size of 1.25 to 1.52 mm yielded better sinter strength and lower RDI compared to sinter with smaller or larger limestone mean particle size. Higher sinter strength is due to better and uniform distribution of limestone particles, and better bed permeability enabled easy assimilation and effective distribution of calcium ferrite phases. The improvement in sinter RDI is due to change in mineralogy of the sinter compared to coarser and finer limestone mean particle size. [ABSTRACT FROM AUTHOR]

The article presents a study on dolomite and dunite magnesium oxide (MgO) influence on sinter mineralogy, quality and productivity. Sintering experiments were carried out using different MgO levels to determine the influence of the oxide. The study reveals that there are greater hematite and less calcium feritite amounts on dunite sinter than in dolomite sinter, and dunite shelter shows better metallurgic properties while dolomite shelter exhibits better physical properties.

The article presents a study on the impact of iron ore pellet size on its properties and microstructure. It cites that pellets properties and microstructure depend on raw material mix proportion. Also, reduction and oxidation process occur under various conditions due to pellet size differences. Pellets size from +eight to -12 mm have good strength with lower reduction degradation index (RDI) which are significantly affected by hematite, magnetite, porosity, pore density and size and slag phase.

The article presents on a study on the effect of alumina in iron ore on sinter properties and productivity in the conventional and selective granulation sintering process. The selective granulation process was used with ore fines of different alumina levels while the conventional granulation process was used with the same levels. It was revealed that increase in alumina levels also increase the pore size and number of pores in both process but the conventional pore shape become more irregular.