IAEA-CU-2006-06 (ancient Chinese ceramic) has been analyzed by k0-INAA and the results for 31 elements are reported. Measurement on Si was done via the (n,p) reaction. The results of 23 elements are within ±10% of the target values and for 2 elements data are reported as information values. The results produce lower relative deviation if compared with the mean reported concentration values submitted by the laboratories participating in the proficiency test. The analysis involves full peak efficiency calibration of the HPGe detector for all counting geometries and characterization of neutron flux at the irradiation channel by determining thermal to epithermal flux ratio and epithermal flux shape factor using Au and Zr flux monitors. The u-score is less than 1 for majority of the elements.
A field trial was conducted in Pindi Bhattian area on sandy loam soil (EC 4.85 dSm-1; pH 7.95; hydraulic conductivity 3.92 cm h-1; bulk density 1.42 g cm-3) to evaluate the growth performance of ten commercially cultivated sunflower genotypes under saline conditions. Ten sunflower genotypes were sown in plots (2.25 m x 15 m) according to a randomized complete block design (RCBD) in three replicates keeping the line-to-line distance of 75 cm and the plant-to-plant distance of 30 cm. The P2O5 (60 kg ha-1) and K2O (100 kg ha-1) fertilizers were applied as SSP and SOP, respectively, at the time of sowing, while N (60 kg ha-1) was applied in two equal splits (one half at sowing time and the other half at first irrigation). Five plants from each plot were randomly selected at maturity to get data on plant height (cm), shoot fresh weight (g), head fresh weight (g), and head diameter (cm). The upper fully matured leaves along with petiole (each from five plants) were collected for leaf area (cm2). Sodium, K, Ca and Mg were analyzed in digested samples using an atomic absorption spectrophotometer. Maximum shoot fresh weights by DK-3915, PARSUN-1 and CRN-1435 closely followed by PARC-9707 were 695.9, 682.3, 669.9 and 578.4 g per plant, respectively. Head fresh weights were highest in CRN-1435, 6451 and DK-3915. The cultivar 6451 produced a comparatively low shoot fresh weight but was significantly (p<0.0001) superior in seed yield (2475 kg ha-1) that was 47% higher than the maximum shoot biomass producing variety DK-3915. The cultivars CRN-1435 and HU-777 were also among the highest seed yielding genotypes. K+ concentrations in leaves, petiole and stem of the genotype Super-25 and cultivar 6451 were maximum compared with the other genotypes. Generally, the cultivars having high concentration of K+ maintained a low concentration of Na+ in its leaves. The high potassium concentrations in leaves, petioles and stems suppressed the detrimental effect of Na+ ions on 1000-grain weight and percentage of oil. High Ca2+ concentrations were observed in leaves, petioles and stems of PARC-9707 and PARC-9706.
Drought stress is limiting global crop production more seriously than ever because of rapid change in global climate. Present investigations were made with a view to understand the traits which can be used as selection criteria for drought tolerance in maize at seedling stage. For this purpose twenty-five maize inbred lines were evaluated under water deficit conditions for traits like fresh shoot weight, fresh shoot length, fresh root length, fresh root weight, leaf venation, stomatal frequency and epidermal cell size. Significant differences were found among the genotypes for various physio-genetic traits. The genotypes 20P2-1, L5-1, 150P2-1, 70NO2-2, 150P1 and L7-2 were found good performer and may be exploited for developing drought tolerant synthetics and hybrids. Fresh shoot length and fresh root weight found overall direct and indirect contributor in fresh shoot weight and they were positive and significantly correlated with fresh shoot weight. Stomatal frequency and epidermal cell size had significantly decreasing direct and indirect effects on fresh shoot weight and significant genetic correlation with it. These results suggested that fresh shoot length and fresh root weight (Increased) stomatal frequency and epidermal cell size (decreased) might be used as selection criterion while selection for high fresh shoot yield under drought conditions.
The intensified stiffness and lightweight structural designed components such as glass fibre-reinforced plastic (GFRP) composites are becoming an alternative to metallic materials to improve the performance of aircraft, shipbuilding and automobiles. Machining damages on the machined texture or subsurface due to the catastrophic nature of composites result in rejection of components at the last stage of production cycle, and necessitate the minimization of such damages by improving the manufacturing quality in secondary manufacturing process. In this chapter, various fibre orientation (FO) angled GFRP workpieces were milled with different tool rake angles (RA) of end milling cutters. Random experiments were done to test the effects of important milling parameters, such as spindle speed, depth of cut (DOC), FO angle and tool’s RA. The machined wall surface and subsurface were thoroughly analyzed by scanning electron microscope. A reasonable reduction in subsurface damages was observed when using the DOC is low (1 mm) and FO angle of workpiece is less than 90°. At this instance, the machining force and the surface roughness are increased proportionally to a DOC, FO angle of the workpiece and tool RAs, where the surface damages were found to be more. It has also been observed that the damage mechanisms of GFRP composite laminates were dominated by their FO angle.