scholarly journals Concentrations of heavy metals in water from the Southern coast of Vietnam

2018 ◽  
Vol 17 (06) ◽  
pp. 42-49
Author(s):  
Tu P. C. Nguyen
Keyword(s):  
Heavy Metals ◽  
Particulate Matters ◽  
Southern Coast ◽  
Aquatic Life ◽  
Quality Guidelines ◽  
Linear Relationships ◽  
Suspended Particulate ◽  
Coast Of Vietnam ◽  
Total Concentrations ◽  
Suspended Particulate Matters

Concentrations of heavy metals (As, Cd, Pb and Hg) in water collected from seven coastal provinces between December 2012 and December 2015 were evaluated. The average total concentrations (μg/L) of As, Cd, Pb and Hg in water ranged from 2.90 to 6.38, < 0.039 to 0.322, 4.26 to 10.5 and < 0.01 to 0.118, respectively. The average concentrations (μg/L) of As, Pb and Hg in suspended particulate matters (SPM) ranged from 0.392 to 7.32, 0.365 to 18.7 and < 0.01 to 0.038, respectively, whereas Cd concentrations were not detected in most of SPM samples. There were positive linear relationships between concentrations of heavy metals in water and SPM, except for Cd. The results showed that the concentrations of metals analyzed in water remained below quality guidelines for the protection of aquatic life recommended by the international and Vietnamese organizations. However, As levels in 2/103 and 5/103 of water samples exceeded the QCVN 10:2015/BTNMT for maximum permitted level using for aquaculture and aquatic life protection (20 μg/L) and the Canadian water quality guidelines for the protection of aquatic life (12.5 μg/L), respectively.

Inorganic and organic chemical characteristics and sources of suspended particulate matters in Ulaanbaatar, Mongolia

2020 ◽  
Vol 54 (4) ◽  
pp. 267-276
Author(s):  
Koshi Yamamoto ◽  
Yuta Suzuki ◽  
Gochoobazar Oyunjargal ◽  
Hiroyuki Fukuda ◽  
Munkhtsetseg Oidov ◽  
...  
Keyword(s):  
Organic Chemical ◽  
Chemical Characteristics ◽  
Particulate Matters ◽  
Suspended Particulate ◽  
Suspended Particulate Matters ◽  
Inorganic And Organic

scholarly journals Biophysical flocculation of suspended particulate matters in Belgian coastal zones

2018 ◽  
Vol 567 ◽  
pp. 238-252 ◽  
Author(s):  
Xiaoteng Shen ◽  
Erik A. Toorman ◽  
Byung Joon Lee ◽  
Michael Fettweis
Keyword(s):  
Particulate Matters ◽  
Coastal Zones ◽  
Suspended Particulate ◽  
Suspended Particulate Matters

Reduction Effects of Suspended Particulate Matters in Air by Thermal Moisture Swing Method

2011 ◽  
Author(s):  
Nagisa Onoda ◽  
Shota Ishiguchi ◽  
Osamu Nakabeppu
Keyword(s):  
Particle Size ◽  
Energy Consumption ◽  
Simple Model ◽  
Experimental Result ◽  
Particulate Matters ◽  
Removal Mechanism ◽  
Air Cleaning ◽  
Suspended Particulate ◽  
Suction Flow ◽  
Suspended Particulate Matters

We are studying the effects of thermal moisture swing air-cleaning method on removal of suspended particulate matter, SPM. This method continuously humidifies sample air with heating and dehumidifies it by cooling, in a channel. It was experimentally demonstrated that the thermal moisture swing method reduces SPM suspended in sample air. The experimental result showed reduction of SPM above 10 nm in particle size, and the removal ratio increased with intensifying the thermal moisture swing. The SPM removal mechanism of this method was theoretically estimated. The estimation suggests that the reasons for the SPM reduction are suction flow accompanying condensation and thermophoresis. These phenomena would transport SPM to cooling wall of the dehumidifier. Also, diffusional deposition and gravitational sedimentation would transport SPM to the wall of the channel. And, the transported particles are separated from the air with adhering on the wall. We estimated the effects of these phenomena on SPM removal using simple model and energy consumption. The estimation qualitatively agreed with the experimental result.

scholarly journals Distribution of heavy metals in sediment along the Southern coast of Vietnam

2020 ◽  
Vol 589 ◽  
pp. 012014
Author(s):  
Nguyen P C Tu ◽  
Nguyen N Ha ◽  
Nguyen N Tri ◽  
Nguyen V Dong
Keyword(s):  
Heavy Metals ◽  
Southern Coast ◽  
Coast Of Vietnam

Variation in Size Distribution of Suspended Particulate Matters in Air With Humidity Swing Operation

2010 ◽  
Author(s):  
Nagisa Onoda ◽  
Osamu Nakabeppu
Keyword(s):  
Particulate Matters ◽  
Nuclear Condensation ◽  
Cleaning Method ◽  
Air Cleaning ◽  
Submicron Size ◽  
Suspended Particulate ◽  
Spm Concentration ◽  
Suction Flow ◽  
Nano Size ◽  
Suspended Particulate Matters

The aim of this study is to develop a new air cleaning method being applicable to suspended particulate matters (SPM) of wide sizes. We experimentally studied about the effects of a humidity swing operation where sample air is continuously humidified with heating and dehumidified with cooling. The total of SPM concentration of sample air decreased with the humidity swing operation; however, the concentration of SPM from 0.3 to 1 μm markedly increased. Suction flow accompanying condensation, cohesion and thermophoresis were considered as the SPM reduction effects. It would appear that the nano-size SPM grew to submicron size by nuclear condensation and submicron size SPM increased. The experimental results showed that the SPM concentration of 0.3 μm or less decreased by 89% and the total of that decreased by 80%. The applicability of the humidity swing operation to removal of SPM including nano size SPM was shown by the results. Also, exponential reduction of the SPM concentration was demonstrated with applying the repeated humidity swing operation in a circulation air-cleaning apparatus. This method is expected to become effective air cleaning method applicable to wide size range of SPM.

Sign in / Sign up

Export Citation Format

Share Document