At each site, three to five 5 cm de

At each site, three to five 5 cm deep samples were taken
and mixed evenly. Then the samples saved in prepared brown
glass bottles were sent back to the laboratory within 24 hr and
frozen in order to avoid contamination of the samples.
Geographical information of the samples was recorded by
the Global Positioning System (GPS) (Table 1).
All the collected samples were freeze-dried, crushed, and
then sieved through a 100-mesh sieve. Approximately 0.5 g
dried surface sediment samples were digested in 5 mLaqua
regia(HNO3:HCl = 1:3) and heated at 140°C until the samples
turned grey. Then 3 mL HClO4 was added into the cooled
samples (Qiao et al., 2011). The residues were diluted with
deionized water to 25 mL for determining concentrations of
heavy metals. Sample solutionswere stored in the refrigerator
at 4°C and then were analyzed for the main heavy metals
including Cr, Cd, Cu, Pb, Zn, Ni and As with an inductively
coupled plasma–optical emission spectrometer (ICP-OES,
Teledyne Leeman Labs, Hudson, NH, USA).

ผลลัพธ์ (อังกฤษ) 2:

At each Site, Three to Five samples were taken 5 cm Deep
and mixed evenly. Then the samples Saved in prepared Brown
Glass bottles were sent back to the Laboratory Within 24 HR and
Frozen in Order to Avoid contamination of the samples.
Geographical information of the samples was Recorded by
the Global Positioning System (GPS) (Table 1).
All. Collected samples were the freeze-Dried, crushed, and
then sieved Through a 100-mesh Sieve. Approximately 0.5 G
Dried surface sediment samples were digested in 5 MLaqua
Regia (HNO3: HCl = 1: 3) and heated at 140 ° C until the samples
turned Grey. Then 3 mL HClO4 was added Into the cooled
samples (Qiao et al., Two thousand and eleven). The residues were diluted with
deionized Water to 25 mL for determining concentrations of
Heavy Metals. Sample Solutionswere stored in the Refrigerator
at 4 ° C and then were analyzed for the Main Heavy Metals
including Cr, Cd, Cu, Pb, Zn, Ni and As with an inductively
coupled Plasma-Optical emission Spectrometer (ICP-OES,
Teledyne Leeman Labs. , Hudson, NH, USA).