Determination of economic injury level of Lipaphis erysimi (Hemiptera: Aphididae) on canola var. Hayola 401 in Khuzestan

Canola, an oil seed with high contents of oil, is a major farming in Khuzestan province, where there is an increase over its cultivation year by year. One of the canola key pests is mustard aphid (Lipaphis erysimi Kalt.) in this province. However, there was not available information on the economic injury level (EIL) of the pest that is much vital for correct decision making on pest control. Therefore, a study on EIL was conducted through complete randomized block design with 5 replications and 11 treatments (0, 5, 10, 15, 20, 25, 30, 35, 40, 45, and 50 aphid per central stem of Hayola 401 variety of canola) inside a netted cage. This research was conducted in Behbahan Agricultural Research Station during 2004-2006. The average of seed yield and also the yeild components was analyzed with Duncanâs multiple range tests. The damage of the aphid was estimated by regression equation. The injury level was estimated by Grain threshold method. The results indicated that EIL was 7.53 and 2.49 cm aphid per central stem of canola in Behbahan region in 2004-2005 and 2005-2006, respectively. Economic threshold (ET) was 5.65 and 1.87 cm2 aphid per central stem of canola

Opportunities and challenges in the use of coal fly ash for soil improvements – a review

Coal fly ash (CFA), a by-product of coal combustion has been regarded as a problematic solid waste, mainly due to its potentially toxic trace elements, PTEs (e.g. Cd, Cr, Ni, Pb) and organic compounds (e.g. PCBs, PAHs) content. However, CFA is a useful source of essential plant nutrients (e.g. Ca, Mg, K, P, S, B, Fe, Cu and Zn). Uncontrolled land disposal of CFA is likely to cause undesirable changes in soil conditions, including contamination with PTEs, PAHs and PCBs. Prudent CFA land application offers considerable opportunities, particularly for nutrient supplementation, pH correction and ameliorating soil physical conditions (soil compaction, water retention and drainage). Since CFA contains little or no N and organic carbon, and CFA-borne P is not readily plant available, a mixture of CFA and manure or sewage sludge (SS) is better suited than CFA alone. Additionally, land application of such a mixture can mitigate the mobility of SS-borne PTEs, which is known to increase following cessation of SS application. Research analysis further shows that application of alkaline CFA with or without other amendments can help remediate at least marginally metal contaminated soils by immobilisation of mobile metal forms. CFA land application with SS or other source of organic carbon, N and P can help effectively reclaim/restore mining-affected lands. Given the variability in the nature and composition of CFA (pH, macro- and micro-nutrients) and that of soil (pH, texture and fertility), the choice of CFA (acidic or alkaline and its application rate) needs to consider the properties and problems of the soil. CFA can also be used as a low cost sorbent for the removal of organic and inorganic contaminants from wastewater streams; the disposal of spent CFA however can pose further challenges. Problems in CFA use as a soil amendment occur when it results in undesirable change in soil pH, imbalance in nutrient supply, boron toxicity in plants, excess supply of sulphate and PTEs. These problems, however, are usually associated with excess or inappropriate CFA applications. The levels of PAHs and PCBs in CFA are generally low; their effects on soil biota, uptake by plants and soil persistence, however, need to be assessed. In spite of this, co-application of CFA with manure or SS to land enhances its effectiveness in soil improvements

Synthesis and Characterization of Polyurethane– Organoclay Nanocomposites Based on Renewable Castor Oil Polyols

In this study, castor oil-based polyurethanes–organoclay (COPUs-Cloisite 30B) nanocomposites are synthesized by mixing polypropylene glycol polyol and dehydrated castor oil (15 %), enforced with C30B nanofillers, at different weight percentages. The physico-chemical behaviors were evaluated by Fourier transform infrared spectroscopy, Fourier scanning electron microscopy, scanning electron microscopy and X-ray diffraction. Thermal stability was found improved up to ~30 °C in the sample with 5 wt% of C30B. Tensile properties depicted an improvement of ~240 % in tensile strength and decrease of ~30 % in elongation with 5 wt% organoclay, respectively. Improved physico-chemical properties of COPUs-C30B signify the usage of COPUs-C30B in the industrial and commercial applications, i.e. coatings, adhesives and automotive applications

Pure Polyurethane and Castor Oil Based Polyurethane: Synthesis and Characterization

In this study, the physico-chemical properties of high performance polyurethane synthesized from poly propylene glycol (PPG) in comparison with a combination of PPG and castor oil, is studied using the in-situ polymerization technique. The variations in properties of both types of polyurethanes are evaluated by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD) and the thermogravimetric analysis (TGA) technique. Tensile strength properties were investigated by film tensile testing equipment. The results indicated the presence of large -CH stretching in the castor oil mixed polyurethane with a larger oxidative thermal stability over pure PPG polyurethanes. The tensile properties were found to be almost comparable in pure and mixed polymers, signifying the usage of mixed polymers in the future to overcome the environmental and economic crisis in polyurethane synthesi

Effect of Potassium Permanganate on Tensile Properties of Sugar Palm Fibre Reinforced Thermoplastic Polyurethane

Background: The high-performance engineering products derived from natural resources are in great demand worldwide, based on renewability and environmental problems. Method: The outcome of Potassium Permanganate (KMnO4) treatment on the tensile behaviours of treated Sugar Palm Fibre (SPF) with 6% NaOH reinforced thermoplastic polyurethane composites was investigated. The sugar palm fibres were treated by 6% NaOH solution, followed by KMnO4 surface treatment of the alkali treated sugar palm fibres. Three different concentrations of KMnO4 (i.e. 0.033, 0.066, and 0.125 %) were applied in the treatment. The extruder and hot press machines were used to mix the sugar palm fibres and polyurethane resin, to get the desired polyurethane composites. Tensile behaviours including (tensile strength and modulus, and the elongation at break) were investigated by following the ASTM D-638 standard. Findings: The highest tensile strength recorded was 8.986 MPa with KMnO4 concentration of 0.125 %, with 6 % alkali pre-treatment. Therefore, the KMnO4 concentration ∼0.125 % exhibited best results for tensile test. Improvements: This study aids an improvement in the alkaline activation method for the TPU/SPF composite fabrication