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Heavy Metals Pollution on the Environment: A Case Study of Seafood and Humans
Susan Okparanta,
Victoria Daminabo
Issue:
Volume 2, Issue 4, December 2018
Pages:
49-55
Received:
15 November 2018
Accepted:
3 December 2018
Published:
26 December 2018
DOI:
10.11648/j.ajese.20180204.11
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Abstract: Heavy metals pollution on the environment (seafood and humans) is a global problem. The concentrations of copper, cadmium and chromium in prawns, periwinkle and croaker fish from Aba area of Abia State were determined using Atomic Absorption Spectrophotometric (AAS) techniques. The values of copper in periwinkle, prawns and croaker fish were 19.22±8.36mg/kg, 2.78± 3.34 mg/kg and 0.6± 0.07 mg/kg respectively whereas the World Health Organization (WHO) limit is 0.5mg/kg for copper in sea food and all samples examined had results which exceeded the WHO acceptable limits in seafood. Cadmium levels was high in croaker fish (1.10± 0.47)mg/kg compared to the WHO limit of 0.5−1.0 mg/kg of cadmium in food and the concentration of cadmium in prawns (0.74±0.5)mg/kg and periwinkle (0.34±0.28)mg/kg were within the WHO acceptable limit of cadmium. The values of chromium levels in periwinkle, prawns and croaker fish were 5.42±3.79 mg/kg, 26.16±2.85 mg/kg and 9.28±8.4 mg/kg respectively and these samples exceeded the WHO acceptable limits of 2.0mg/kg set for chromium in seafood. The results obtained from this study show that periwinkle and prawns bioaccumulated cadmium.
Abstract: Heavy metals pollution on the environment (seafood and humans) is a global problem. The concentrations of copper, cadmium and chromium in prawns, periwinkle and croaker fish from Aba area of Abia State were determined using Atomic Absorption Spectrophotometric (AAS) techniques. The values of copper in periwinkle, prawns and croaker fish were 19.22±...
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The Effect of Mass Transfer Resistance on the Adsorption Rate of Phenol in Soil Sediments
Eugene Ehidiamhen Yakubu,
Chiedu Owabor
Issue:
Volume 2, Issue 4, December 2018
Pages:
56-64
Received:
12 November 2018
Accepted:
27 November 2018
Published:
14 January 2019
DOI:
10.11648/j.ajese.20180204.12
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Abstract: This study was aimed at evaluating the effect of mass transfer resistance to the transport of phenol in soil sediments. Batch adsorption experiments were conducted using phenol in homogenous soil sediments (clay and sand). The Physico-chemical properties of the soil sediments were determined and sorption behaviour kinetically modelled using the Pseudo-first order, Pseudo-second order, Intra-particle, Elovich, and Power function models. The sorption behaviour was best modelled with the intra-particle model (R2 ˃ 0.9628). The rate limiting step and mass transfer resistance were determined by the Boyd plot, Homogenous pore diffusion model (HPDM) and the modified Furusawa -Smith equation. The Boyd plots indicated external mass transfer as the rate-determining step for the phenol/clay and phenol/sand systems; the HPDM model gave a poor fit (R2 ≈ 0.6) for the phenol sorbate systems, corresponding with projections from the Boyd plots. From the results of the study, the rate controlling step for phenol sorption in the sediments was predominantly due to external mass transfer resistance. A comparative analysis between the two sediments using the Furusawa -Smith equation gave the mass transfer coefficients for clay and sand to be 2.09205E-14 m s−1 and 4.17537E-12 m s−1 respectively, showing that as the particle size decreased, the more significant the effect of external mass transfer effect on the sorption rate.
Abstract: This study was aimed at evaluating the effect of mass transfer resistance to the transport of phenol in soil sediments. Batch adsorption experiments were conducted using phenol in homogenous soil sediments (clay and sand). The Physico-chemical properties of the soil sediments were determined and sorption behaviour kinetically modelled using the Pse...
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Quantitative Analysis of Influencing Factors of Air Pollution and Evolution Law of Nitrogen Oxide Distribution in Beijing, Tianjin and Hebei
Zuo Zhengdong,
Wan Guangcai,
Huang Xiaohui,
Shao Zhichao
Issue:
Volume 2, Issue 4, December 2018
Pages:
65-71
Received:
19 August 2018
Accepted:
7 December 2018
Published:
15 January 2019
DOI:
10.11648/j.ajese.20180204.13
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Abstract: Nowadays, the continuous fog and haze weather has made people more and more concerned about air pollution.And the air pollution problem in the Beijing-Tianjin-Hebei region is the highest in China. The high-density population distribution, crowded urban traffic and large-scale heavy industry bases are the main reasons for this phenomenon.This study analyzes the problem of air pollution sources and changes on gradient of air concentrations. Based on quantitative analysis, variable control, linear fit and two order parabolic partial differential equation,the principal component analysis model and Single Gaussian plume diffusion sources model are developed. Coupled with these models, MATLAB and Microsoft Excel are also further made use of to analyze the gradient of pollutant concentration around the plant at different time and judge the air quality level.Finally, it can be concluded that the main sources are industrial emissions, fuel combustion, vehicle exhaust and industrial waste water as well as the main influencing parameters are PM2.5 and PM10.0. And the farther away from the chimney, the lower the concentration of Nitrogen oxides was.The model is suitable for analyzing the influence of pollutants emitted from plant chimneys on the surrounding area.It can also help the Environmental Protection Department to formulate emission standards to promote sustainable economic development.
Abstract: Nowadays, the continuous fog and haze weather has made people more and more concerned about air pollution.And the air pollution problem in the Beijing-Tianjin-Hebei region is the highest in China. The high-density population distribution, crowded urban traffic and large-scale heavy industry bases are the main reasons for this phenomenon.This study ...
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Preliminary Bioleaching of Heavy Metals from Contaminated Soil Applying Aspergillus niger F2
Deng Xinhui,
Chen Runhua,
Shi Yan,
Zhuo Shengnan
Issue:
Volume 2, Issue 4, December 2018
Pages:
72-78
Received:
23 November 2018
Accepted:
8 December 2018
Published:
22 January 2019
DOI:
10.11648/j.ajese.20180204.14
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Abstract: A new strategy of heavy metal biobleaching was proposed based a fungal strain identified as Aspergillus niger and named F2. F2 displayed great ability of heavy metal resistance and organic acid production. The temperature, pH, carbon source, and nitrogen source have great influences on the heavy metal bioleaching from contaminated soil by F2. The optimum temperature and pH for biobleaching were 30°C and 5.0, respectively. The total heavy metal bioleached by F2 with sucrose, glucose, maltose, lactose and starch as carbon source were 69.86%, 66.57%, 64.59%, 0.92%, and 69.01%, respectively, while the total heavy metal bioleached by F2 with NaNO 3, NH4NO3, peptone, and yeast extract as nitrogen source were 64.10%, 64.05%, 65.87% and 66.27% individually. Our finding provided a new perspective for the treatment of heavy metal contaminated soil.
Abstract: A new strategy of heavy metal biobleaching was proposed based a fungal strain identified as Aspergillus niger and named F2. F2 displayed great ability of heavy metal resistance and organic acid production. The temperature, pH, carbon source, and nitrogen source have great influences on the heavy metal bioleaching from contaminated soil by F2. The o...
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Study on the Characteristics of Unorganized Emission of Volatile Organic Compounds in Chemical Industry--Taking Tianjin Chemical Enterprises as an Example
Xie Tian,
Yang Wen,
Guo Ting,
Bai Zhipeng,
Tang Jiayi
Issue:
Volume 2, Issue 4, December 2018
Pages:
79-84
Received:
22 November 2018
Accepted:
17 December 2018
Published:
22 January 2019
DOI:
10.11648/j.ajese.20180204.15
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Abstract: In order to study on the unorganized emissions characteristics of volatile organic compounds (VOCs) of Tianjin chemical industry, three plants located in a chemical park in Tianjin were chosen. Air samples on the plant boundary and within the enterprise were collected through air bag, and the VOCs emission levels and component characteristics were measured using proton transfer reaction time of flight mass spectrometer (PTR-TOF-MS). The analysis results showed that, (1) the emission level of VOCs of three plants were different. The level of VOCs in tank area was directly related to the tank type, and the level in storage tank area was related to whether it was sealed, (2) the components of VOCs emitted from unorganized sources mainly were saturated alkanes represented by C2, C2, C8, C9 and C11 and oxygenated volatile organic compounds (OVOCs) represented by CH4O, (3) it was found that alkane substance was a large class of VOCs component in chemical industry plant, so alkanes should be controlled in priority.
Abstract: In order to study on the unorganized emissions characteristics of volatile organic compounds (VOCs) of Tianjin chemical industry, three plants located in a chemical park in Tianjin were chosen. Air samples on the plant boundary and within the enterprise were collected through air bag, and the VOCs emission levels and component characteristics were ...
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