This research studied a new spectrophotometric method for measuring the chemical oxygen demand (COD) of seawater. In this method, the COD was measured using a spectrophotometer instead of titrating with sodium thios...This research studied a new spectrophotometric method for measuring the chemical oxygen demand (COD) of seawater. In this method, the COD was measured using a spectrophotometer instead of titrating with sodium thiosuiphate. The measuring wavelength was selected to be 470 nm, and the COD of three standard glucose solutions (COD = 0.5, 1.5 and 2.5 mgL^-1, respectively) and two seawater samples (from the South Yellow Sea and Jiaozhou Bay) were measured using the spectrophotometric method and titrimetric method respectively. The results showed that the spectrophotometric method was somewhat better than the titrimetric method. The relative standard deviation (RSD) of the spectrophotometric method was less than 2.7%, and the recovery of seawater samples ranged from 96.3% to 103.8%. In addition, the spectrophotometric method has other advantages such as expeditiousness, operation simplicity, analysis automatization, etc. Therefore the spectrophotometric method can be used to measure the COD of seawater with satisfactory results.展开更多
A field trial was carried out in Ferk6 2 Sugar mill located in northern Ivory Coast, in order to study sugarcane growth and yield response to deficit irrigation imposed over the yield formation stage. The crop used wa...A field trial was carried out in Ferk6 2 Sugar mill located in northern Ivory Coast, in order to study sugarcane growth and yield response to deficit irrigation imposed over the yield formation stage. The crop used was a first ratoon Co 957, a non flowering late season sugarcane variety. The experiment was completely randomized following a one-factor design with 4 water deficit treatments in 3 replicates. It came out that the optimum water deficit treatment reached 20%, i.e., 80% of crop water requirements were satisfied through irrigation. That treatment gave 7.9 kg cane/m3 or 0.98 kg sugar/m3 as irrigation water use efficiency. Relatively low crop growth rates (0.2-0.4 cm/day) as well as low cane yields (24.5-78.4 t/ha) were obtained as a result of an intensive and persistent dry season occurred over the yield formation stage. In line of prevailing climatic conditions, cane juice quality measured was particularly high on Co 957 which used to be a moderately performing variety in Ferk6 2 sugar mill.展开更多
文摘This research studied a new spectrophotometric method for measuring the chemical oxygen demand (COD) of seawater. In this method, the COD was measured using a spectrophotometer instead of titrating with sodium thiosuiphate. The measuring wavelength was selected to be 470 nm, and the COD of three standard glucose solutions (COD = 0.5, 1.5 and 2.5 mgL^-1, respectively) and two seawater samples (from the South Yellow Sea and Jiaozhou Bay) were measured using the spectrophotometric method and titrimetric method respectively. The results showed that the spectrophotometric method was somewhat better than the titrimetric method. The relative standard deviation (RSD) of the spectrophotometric method was less than 2.7%, and the recovery of seawater samples ranged from 96.3% to 103.8%. In addition, the spectrophotometric method has other advantages such as expeditiousness, operation simplicity, analysis automatization, etc. Therefore the spectrophotometric method can be used to measure the COD of seawater with satisfactory results.
文摘A field trial was carried out in Ferk6 2 Sugar mill located in northern Ivory Coast, in order to study sugarcane growth and yield response to deficit irrigation imposed over the yield formation stage. The crop used was a first ratoon Co 957, a non flowering late season sugarcane variety. The experiment was completely randomized following a one-factor design with 4 water deficit treatments in 3 replicates. It came out that the optimum water deficit treatment reached 20%, i.e., 80% of crop water requirements were satisfied through irrigation. That treatment gave 7.9 kg cane/m3 or 0.98 kg sugar/m3 as irrigation water use efficiency. Relatively low crop growth rates (0.2-0.4 cm/day) as well as low cane yields (24.5-78.4 t/ha) were obtained as a result of an intensive and persistent dry season occurred over the yield formation stage. In line of prevailing climatic conditions, cane juice quality measured was particularly high on Co 957 which used to be a moderately performing variety in Ferk6 2 sugar mill.