Search Results
You are looking at 1 - 6 of 6 items for
- Author or Editor: Ali Salem x
- Refine by Access: All Content x
Water stress is a severe limitation for crop growth especially in arid and semi-arid regions of the world, as it has a vital role in plant growth and development at all growth stages. The aim of the present study was to evaluate the differential responses of twelve sunflower genotypes to three levels of water supply and select the most suitable one for such conditions. Two field experiments were conducted under adequate (7140 m3/ha), moderate (4760 m3/ha) and severe (2380 m3/ha) water regimes to evaluate the chlorophyll index, transpiration rate, leaf water content, plant height, head diameter, seeds/head, 1000-seed weight, seed and oil yield of the genotypes. Moderate and severe levels of drought had a significant impact on the transpiration rate, leaf water content, yield-contributing characters and oil yield of all the sunflower genotypes. However, the sunflower genotypes showed different responses to the different water regimes. The highest seed and oil yields were attained in L990 and Giza 102 in the case of adequate water supplies, while L38 was the best under moderate and severe drought conditions. On the basis of the results, sunflower genotype L990 could be recommended for growing when adequate water supplies are available, and L38 under moderate and severe water regimes to obtain high seed and oil yields.
Abstract
Oil shale is the most abundant fossil energy resource discovered in Jordan, ranking third after the USA and Brazil in terms of oil shale reserves. This asset is considered to be Jordan's most extensive domestic fossil-fuel source. The identified reserves of this oil shale are huge and sufficient to satisfy the national energy needs for hundreds of years. Numerous geologic studies have shown that the country contains several oil shale deposits. These deposits are regarded as the richest in organic bituminous marl and limestone that occur at shallow depth. Jordanian oil shale is generally of a good quality, with relatively low ash and moisture contents, a gross calorific value of 7.5 MJ/kg, and an oil yield of 8 to 12%. The spent shale has residual carbon content that may be burned to produce further energy, and ash that can be used for cement and building materials. The current study summarizes the results of the former feasibility studies and discuses the scope of future usage of Jordanian oil shale. The value of this oil shale and its associated products is highlighted herein.
Abstract
Steel fibers recovered from recycled tires were considered for use as reinforcement in concrete to improve the tensile properties of concrete as well as being an economically viable and environmentally friendly alternative. This paper investigates the effect of purified and non-purified recycled tire steel fiber in concrete with a constant fiber proportion of 30 kg m−3 to determine properties in fresh and hardened concrete. The results indicate that concrete with purified tire fibers have better tensile properties than those with non-purified tire fibers. Density, strength, and toughness significantly increase but workability tends to decrease when using recycled tire steel fiber as reinforcement in concrete.
Abstract
Kits were developed-for the sterile labelling of phytate with99mTc. The effect of molar ratio of phytate to stannous chloride, pH, dilution of the Sn-phytate with99mTc-generator eluate, time of incubation, the shelf life of99mTc-phytate and the storage time of Sn-phytate on the labelling yield of phytate with99mTc was investigated using paper chromatography and gel chromatography column scanning method (GCS). Organ distribution was performed in rabbits and mice. Excellent human liver scans were obtained.
In order to breed rice cultivars for resistance to the brown planthopper, Nilaparvata lugens Stål (BPH) in Bangladesh, were evaluated for resistance in greenhouse screening tests. Over a period of six years (2005–2010), 1,767 entries/cultivars were screened using the plant hopper screening (PHS) system. The results showed 87 donors possessing different levels of resistance to the BPH. One exotic cultivar was highly resistant to the BPH and 86 materials showed medium resistance (tolerance) to the BPH. The rest of the materials including germplasm, F2, exotic, IRBPHN (International Rice Brown Planthopper Nursery) and advanced lines were susceptible. Most of entries coming from the International Rice Research Institute (IRRI) via the IRBPHN were moderately resistant.
Abstract
Concrete is the most widely used construction material in the world. Over ten billion tons of concrete are being produced each year resulting in exhaustion of natural materials and an enormous carbon footprint. One of the primary goals of concrete technology today is to reduce the use of Portland cement and natural fine aggregates by partially replacing them with various waste materials and by-products of industrial processes. The paper summarizes the results of a study where the partial replacement of river sand and Portland cement was successfully applied using steel slag aggregate, silica fume and glass waste.