Riaz Ahmad

Development of energy consumption map for orthogonal machining of Al 6061-T6 alloy:

The major source of environment and economic impact of machine tools has been attributed to their energy consumption. This article, therefore, proposes a novel energy mapping approach to evaluate specific cutting energy consumption with respect to cutting parameters. Unlike the studies presented earlier, which are machine-tool-specific, this study focuses on the basic tool–workpiece interaction for energy consumption analysis. The presented energy map reveals different energy consumption regions at varying machining parameters (feed and speed) during orthogonal machining of Al 6061-T6 alloy. The chip formation analysis indicates a strong correlation with the different energy consumption regions identified on the energy map. It has been observed that feed is the major contributing factor towards shear plane angle during chip formation as compared to cutting speed. Therefore, increasing feed results in a higher shear angle and consequently lowering the specific cutting energy as indicated on the energy map. Selection of machining parameters corresponding to the lowest specific cutting energy consumption region, as identified on the energy map, can result in energy savings up to 27% per kg of material removed. The developed map can be used for selection of suitable energy-efficient cutting parameters.

Agronomic Biofortification of Fodder Sorghum with Zinc under Different Levels of Nitrogen

Zinc (Zn) deficient soil prevails throughout the world and it has become the bottleneck in achieving production potential and quality of crops. The negligible use of micronutrients along with irregular use of macronutrients is practised for fodder production in Pakistan. Varying levels of zinc (0, 5, 10 and 15 kg ha-1) and nitrogen (0, 60, 120 and 180 kg ha-1) were evaluated for their effect on yield, quality and zinc uptake on fodder sorghum (variety Hegari) in a field experiment for two consecutive years (2014 and 2015). Data were analysed by using Fishers’ analysis of variance (at p<0.05) and response surface methodology (RSM). Correlation between different parameters was also studied. Application of zinc and nitrogen improved the plant height, leaf area plant-1, green fodder yield, dry matter yield, crude protein percentage and zinc content of plant but decreased the neutral detergent fiber, acid detergent fiber and ash percentage. Values for different parameters recorded at second and third levels of zinc and nitrogen were remained at par with each other. Application of 10 kg ha-1 zinc and 120 kg ha-1 nitrogen showed an average increase of 7.3 and 18.6% in green fodder yield while 12.1 and 15.8% in dry matter yield, respectively. Similarly 6.1 and 7.5% increase in crude protein was noted over control. Correlation between NDF and ADF was negative with rest of the studied parameters. In conclusion, Zn2 and N2 gave the best results in term of yield and quality of fodder sorghum.

Influence of Different No-till Techniques at Varying Heights of Standing Rice Stubbles on the Wheat Performance

In rice-wheat cropping system of Punjab, Pakistan, seeding directly into the standing rice stubbles is gaining popularity. This study was conducted to develop the most favorable and economical no-till technique for wheat sowing in combine-harvested paddy fields with different residue conditions. The experiment was comprised of three no-till techniques viz. (1) turbo seeder, (2) happy seeder and (3) zone disk tiller. There were four heights of standing rice stubbles viz. (1) 15 cm, (2) 30 cm, (3) 45 cm, and (4) 60 cm. Different no-till techniques at various heights of standing rice stubbles significantly affected the stand establishment and yield related traits of wheat during both growing seasons. Turbo seeded plot showed 12‒14% more total soil porosity in comparison with zone disk tiller sown field. Conversely, wheat plots sown by zone disk tiller exhibited 8% more soil bulk density than turbo seeder sown field. Better stand establishment and grain yield were observed in turbo seeded wheat in comparison with happy seeder and zone disk tiller sown wheat. Among the stubble heights, wheat crop sown in standing rice stubbles at 45 cm height performed the best with maximum germination, 1000 grain weight and grain yield. Furthermore, turbo seeder in standing rice stubbles at 45 cm height significantly produced 32‒35% more benefit cost ratio than zone disk tiller at 15 cm stubble height during both years of experiment. In crux, direct drilling of wheat by turbo seeder in rice field combine harvested at 45 cm stubble height is the most viable technology for rice-wheat cropping system.