2016年8月22日星期一
What is Trifluralin,and for sale
Trifluralin, a pre-emergence soil applied herbicide and incorporated ground, working since 1963 in environmental chemistry and fate of dinitroaniline in agriculture, including trifluralin has been extensively studied in agricultural soils. Probst et al. (1975) and Helling (1976) summarized on mobility, persistence pre-1975 data and degradation or metabolism of dinitroaniline as a group. Since then, many studies on the fate of dinitroanilines have been conducted, especially trifluralin to understand the environment, their continued degradation in soil, the potential of mobility and persistence and concentration of the environment in water and air. This report briefly summarizes the historical data, mainly focuses on the post-1975 data on degradation, mobility and persistence of trifluralin in soils and possible concentrations in water and air. Trifluralin is easily degraded by sunlight in all media, with half-lives (t1 / 2) minutes to several months, depending on the substrate. In addition, other derivative processes such as microbial and chemical, are also effective in the soil, water and sediment. was identified and characterized several trifluralin degradation products, both. under photolysis and follows the aerobic and anaerobic metabolism in the soil systems and water-sediment The differences between the different channels of trifluralin appear to be more quantitative qualitative, eventually leading to the same final products are subjected the obligation or the mineralization time. The general lack of accumulation of trifluralin degradation products indicates that this product. Furthermore, in the same mechanisms of degradation than the parent compound Trifluralin has a solubility in water and low is strongly bound to soil particles; Koc mean values are 4000-13000. Once applied and incorporated into the soil, trifluralin remains relatively motionless with little or no possibility of contamination of groundwater in or near the treated areas. trifluralin residues in soil layers are subject to loss by transport in runoff or volatilization into the air. seasonal losses in runoff are applied consistently within 0.5% of the quantities, with concentrations in runoff Edge-of-the-box <typically 1.0 microgram L-1. Therefore trifluralin is rarely detected in the surface water and, if necessary, usually occurs below the quantization level. seasonal trifluralin losses applied to that in the atmosphere of 25% to be as high. Maximum concentrations of trifluralin residues in the air over the treated areas are within 2-3 micrograms m-3 after application of the area decreases to <100 ng m-3 in ambient air of intensive use, display on the rapid degradation of the air. were reported trifluralin residues to <100 pg m-3 in the atmosphere in remote areas, the long-term non-use transportation potential for acceptance. However, there is a general lack of understanding of the mechanisms controlling their potential for long-distance transport in particular, reflect the rapid photodegradation of steam and state solution. The persistence of trifluralin in agricultural soil after installation varies, depending on various factors such as the depth of the installation, soil moisture, soil temperature, soil gas and content soil organic matter. half-life estimation under a variety of agronomic conditions ranging from 25 to> 201 d, so perseverance of "average" to "persistent" to categorize. The half-life of estimated data for trifluralin in the agricultural, but can not be extrapolated to other scenarios, such as dissipation in non-target areas where trifluralin residues, if any, are deposited mainly on surfaces. Surface deposits on non-target areas, as opposed to soil residues incorporated, would be subject volatilization and photolysis and therefore short-lived.
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