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The association between the diesel exhaust particle exposure from bus emission and the tubular epithelial cell deformation of rats Texte intégral
2020
Wardoyo, Arinto Yudi Ponco | Juswono, Unggul Pundjung | Noor, Johan Andoyo Effendi
The diesel vehicle emissions regarding particles have become a problem due to human health adversely. Especially ultrafine particles (diameter ≤ 100 nm) can deeply penetrate the human body leading to cell deformation. Investigation of the diesel ultrafine particle exposure to the cell deformation has become a challenge to build up understanding the impacts of ultrafine particles on human health. Moreover, the relationship between high exposure to diesel ultrafine particles and the deformation of the rat’s tubular epithelial cells is not clear. In this study, we investigated the impact of the diesel ultrafine particle exposure to the rat’s tubular cells. Three diesel busses were used as the sources of the particles, while 50 rats were used as the experimental animals. The diesel emission was filtered using an N95 particulate filter and a suction pump. The rats were exposed to the diesel ultrafine particle emission for 100 s with three different concentrations C₁, C₂, and C₃ for eight consecutive days. All rats were sacrificed on the day after exposures to examine the histological images. The results showed that the deformation level of the tubular epithelial cells was positively associated with the concentration of the ultrafine particles.
Afficher plus [+] Moins [-]Experimental investigation of biodiesel production from Madhuca longifolia seed through in situ transesterification and its kinetics and thermodynamic studies Texte intégral
2020
Mani, Yuvarani | Devaraj, Thiruselvi | Devaraj, Kubendran | AbdurRawoof, Salma Aathika | Subramanian, Sivanesan
The present investigation aims to develop simultaneous extraction and conversion of inedible Madhuca longifolia seed oil into biodiesel by one-step acid-catalyzed in situ transesterification/reactive extraction process. Six different types of pretreatment were used to assess maximum yield of biodiesel. The maximum yield of 96% biodiesel was acquired with ultrasonic pretreatment at 1% moisture content, 0.61 mm seed grain size, 55 °C temperature, 400 rpm stirring speed, 15 wt% catalyst (H₂SO₄) concentration, and with 1:35 seed oil to methanol ratio in a time period of 180 min. This reaction kinetics precedes first order also the finest value of rate constant and activation energy were calculated as 0.003 min⁻¹ and 14.840 kJ mol⁻¹. The thermodynamic energy properties ΔG, ΔH, and ΔS are computed as 96457.172 J/mol, 12121.812 J/mol K, and − 257.12 J/mol K correspondingly. The enumerated outcome illustrates a heat absorb non-spontaneous/endergonic and endothermal reaction. The result of proposed work unveils ultrasonic pretreatment escalates the biodiesel efficiency and reactive extraction exemplifies the clean, cost-effective single-step approach for production of biodiesel from non-edible sources.
Afficher plus [+] Moins [-]Evaluation of the radiological quality of water released by a uranium mining in Brazil Texte intégral
2020
de Souza Pereira, Wagner | Kelecom, Alphonse | Lopes, Jose Marques | do Carmo, Alessander Sá | de Azevedo Py Júnior, Delcy | da Silva, Ademir Xavier
A mine in an area of naturally occurring radioactive materials (NORM), characterized by acid mine drainage, generates effluents with natural radionuclide concentrations, usually above the limits authorized by the regulator. The plant exploiting NORM controls the water quality and discharges it into the aquatic environment after meeting technical requirements. Downstream, water usage is unrestricted. In order to reach activity concentrations in the released effluents below the authorized values, the facility applies a chemical treatment to the effluent. Then, to ensure the effectiveness of the treatment, the facility performs sampling of treated effluent and determines the activity concentration of natural radionuclides (Uₙₐₜ, ²²⁶Ra, and ²¹⁰Pb from the uranium series and ²³²Th and ²²⁸Ra from the thorium series). In the current study, the proportion and distribution of these radionuclides between the soluble and particulate fractions were determined. The measured activity concentrations were compared with the values proposed by the World Health Organization and Brazilian legislation, as well as other authorities, as regards the potable use from the radioprotection point of view. It was observed that the radionuclides are not in secular equilibrium. The fractions contribute differently to the total release of radionuclide, and there is no linear relationship between the fractions. The average activity concentrations did not result in radiological restrictions to water use, and the committed effective dose due to ingestion was estimated at 0.06 mSv y⁻¹. Therefore, there is no radiological restriction to water use, since the dose which was found was below the constraint value for the public.
Afficher plus [+] Moins [-]Application of agronomical approaches to rehabilitating territories of the Republic of Belarus affected by the Chernobyl disaster Texte intégral
2020
Radziuk, Hanna | Shapsheeva, Tatiana
The environmental radiation pollution resulting from the Chernobyl nuclear disaster in 1986 is one of the main factors limiting agriculture in the eastern regions of Belarus. In the first decade after the accident, the need to mitigate the effects of radiation had a key role in the implementation of countermeasures. As a result, there are widespread areas of high soil fertility potential in the contaminated zone. Today there is a possibility to include new crops (e.g. sugar beet [Beta vulgaris L.]) into regular crop rotation to increase the effectiveness of agriculture and to use the accumulated soil fertility potential. The article discusses a possible agronomic approach to estimating specific fields (working plots) at the scale of agricultural enterprises for placement of sugar beet. The territory of the Mahilyow region of the Republic of Belarus was examined from the perspective of soil suitability to the cultivation of sugar beet. Along with estimating radionuclide accumulation by sugar beet roots, the areas of soils suitable for sugar beet within agricultural enterprises were calculated for selected districts. It was revealed that sugar beet has low ability to absorb radiocaesium and radiostrontium from soils. The contamination density does not restrict the possibility for placement of sugar beet. Instead, soil fertility, specifically content of plant-available phosphorus and boron, was the limiting factor in that. Based on data from field experiments and soil fertility data, a number of enterprises were selected where sugar beet could be included into crop rotations to high economic effect.
Afficher plus [+] Moins [-]A novel hydroxofluorographene-coated melamine foam for efficient and repeatable oil removal from water Texte intégral
2020
Zhou, Xinyi | Li, Yi | Zhang, Chi | Wang, Yuming | Lu, Yumiao
With the frequent occurrence of oil spill accidents and the continuous discharge of oily water during oil production and transportation, effective oil removal from environmental water by adsorption still faces severe challenges. Here, a novel absorbent hydroxofluorographene-coated melamine foam, namely G(OH)F@MF, with high affinity to oils was fabricated via stepwise assembly. The G(OH)F@MF absorbent achieved effective removal of various oils within 1 min with relatively high adsorption capacities for petrol (89.34 g/g), lubricating oil (89.60 g/g), and peanut oil (104.79 g/g). Furthermore, it could be regenerated by simply squeezing and reused for more than 10 times with an adsorption capacity exceeding 37.12 g/g. In addition, the results indicated that the G(OH)F@MF absorbent was suitable for oil cleanup at a wide range of pH values (4–12) and temperatures (5–45 °C). The adsorption performance of the material was stable in the presence of natural organic matter and even in different water environments. This study can provide a novel sorbent and method for the green, rapid, recyclable, and stable removal of oils from environmental water.
Afficher plus [+] Moins [-]Treatment efficiency of iron-rich acid mine drainage in a tri-unit pilot system Texte intégral
2020
Genty, Thomas | Bussière, Bruno | Benzaazoua, Mostafa | Neculita, Carmen Mihaela | Zagury, Gérald J.
Treatment efficiency of iron-rich acid mine drainage (AMD; pH 3, and 2 and 4 g/L Fe) was tested in a laboratory tri-unit pilot-scale reactor (2.65 m³) for 1 year. The first unit consisted of a passive biochemical reactor (PBR1), filled with reactive mixture (50% of manure, sawdust, maple chips, compost, urea, sediment, and sand; 50% of calcite), with the aim to neutralize acidity and to partially remove metals. The second unit contained wood ash and acted as neutralizer and iron retention filter (by sorption and precipitation). The last unit was a second polishing PBR2, filled with reactive mixture (98% of manure, sawdust, maple chips, compost, urea, sediment, and sand; 2% of calcite), which aim was to remove the residual metals. The results showed that pH increased to about 6 and redox potential decreased significantly (from 550 mV to −100 mV). Iron, the most challenging metal in the AMD, decreased from 4 g/L (the highest tested concentration) to approximately 100 mg/L. The performance of the multistep treatment system was controlled by the capacity of the wood ash to immobilize iron.
Afficher plus [+] Moins [-]Mercury bioaccumulation in zooplankton and its relationship with eutrophication in the waters in the karst region of Guizhou Province, Southwest China Texte intégral
2020
Yao, Cong | He, Tianrong | Xu, Yiyuan | Ran, Shu | Qian, Xiaoli | Long, Shengxing
Zooplankton play an important role in the transfer of mercury (Hg) from the lower to upper trophic positions in the food chain. In this study, total mercury (THg) and methylmercury (MeHg) levels were measured in three size fractions of zooplankton collected from three reservoirs (Hongfeng, Baihua, and Aha Reservoir) and one wetland in karst areas to understand mercury accumulation in zooplankton from alkaline environments. The results showed that the alkaline waters had lower zooplankton MeHg levels (0.1 to 66.8 ng g⁻¹) than most of the acidic waters reported. However, the zooplankton THg levels (6.3 to 494.9 ng g⁻¹) were comparable. The macro-zooplankton (> 500 μm) had significantly higher THg and MeHg levels than meso-zooplankton (116 to 500 μm) in the three reservoirs at all seasons, which showed biomagnification of mercury in the food chain. The correlation between Hg in water and zooplankton and Hg in zooplankton of different sizes indicated that THg bioaccumulation in zooplankton was related to the THg levels in water; however, MeHg bioaccumulation in zooplankton was controlled by many other factors, such as their feeding and living habits. In the three reservoirs, the THg and MeHg concentrations in zooplankton decreased with increasing eutrophication. However, compared with the three reservoirs, Caohai Wetland, with large amounts of aquatic plants, had a much lower trophic level and higher MeHg content in water but much lower zooplankton MeHg levels and bioaccumulation factors (BAFs). The large amounts of plant residue might dilute mercury in the food chain, revealing that high primary production could result in lower Hg bioaccumulation, rather than only being influenced by nutrient levels.
Afficher plus [+] Moins [-]A preliminary study of heavy metals pollution in the sandy dust storms and its human risk assessment from middle and south of Iraq Texte intégral
2020
Kadhum, Safaa Abdalzahra
Sandy dust storms in Iraq represented a serious problem for human health, not only in Iraq but also extended to be in other countries. Therefore, this study has assessed five heavy metals (Cd, Ni, Zn, Pb, and Fe) in the sandy dust storms from ten locations in the middle and south of Iraq. Contamination levels in the dust were evaluated by using various pollution indices. Heavy metals recorded a high pollution load index (PLI) that considered as baseline pollution in the dust. The geo-accumulation index (Igeo) values were moderately contaminated for Cd, and Pb, in case of potential ecology risk ([Formula: see text]), was a considerable risk for Cd. Based on multivariate analysis which is performed by principal component analysis (PCA), correlation analysis (r²) and cluster analysis (CA) revealed that heavy metals in sandy dust storms were possible from anthropogenic activities. The Cd, Ni, Zn, and Fe were from the same pollution sources, while Pb element was from the different pollution sources. Therefore, this data will be useful as sources to the Quality Control Department in Iraq to establish perfect qualitative standards and also to acquire a better quality of the atmosphere in Iraq and the region.
Afficher plus [+] Moins [-]Surfactant-modified titania for cadmium removal and textile effluent treatment together being environmentally safe for seed germination and growth of Vigna radiata Texte intégral
2020
Das, Paromita | Bahadur, Nupur | Dhawan, Vibha
The present work describes synthesis, detailed characterization, and application of bare and surfactant-modified titania nanomaterials (NMs) for various wastewater treatment applications as individual cases like cadmium (Cd) removal, methylene blue (MB) dye degradation, and treatment of real textile and dyeing industry effluent. These NMs are used as adsorbents and photocatalysts in an indegenously developed end-to-end treatment process and a photocatalytic reactor for treatment of textile wastewater. The used NMs are suitably filtered and recovered for reuse; however, still this work focusses on the extent of potential risk and environmental safety of these engineered NMs towards seed germination and plant growth, in the event they escape wastewater treatment plants and reach out to natural water bodies and soil systems, accumulate over a period of time, and comes in contact with plant species. For synthesis, sol-gel method was utilized; cetyltrimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) were used as cationic and anionic surfactants, respectively, to act as particle growth templates and improve surface morphology. Detailed characterization involved XRD (X-ray diffraction), FTIR (Fourier-transform Infrared Spectroscopy), SEM (Scanning Electron Microscopy), TEM (Transmission Electron Microscopy), EDX (Energy Dispersive X-ray analysis), and BET (Brunauer-Emmett-Teller) surface area analysis. Improved morphology and surface properties, from irregular shape in Bare TiO₂ to spherical shape in surfactant-modified titania, led to enhanced Cd removal and MB dye degradation efficiency. Bare TiO₂ was used for complete treatment of textile wastewater, which took 5 h in achieving water quality, which is safe for discharge and reuse as per norms of Central Pollution Control Board (CPCB), Govt. of India. Phytotoxicity studies of these NMs at a wide concentration range (0–1000 mg L⁻¹⁾ were undertaken towards Vigna radiata, and 500 mg L⁻¹ concentration was found to be optimally safe for seed germination and plant growth.
Afficher plus [+] Moins [-]Influence of Pseudomonas japonica and organic amendments on the growth and metal tolerance of Celosia argentea L Texte intégral
2020
Iqbal, Ameena | Mushtaq, Muhammad Umair | Khan, Aqib Hassan Ali | Nawaz, Ismat | Yousaf, Sohail | Zeshan, | Iqbal, Mazhar
In this study, a pot experiment was piloted in a greenhouse to evaluate the potential of Celosia argentea var. cristata L. for tolerating/accumulating heavy metals in synthetic wastewater in the presence of Pseudomonas japonica and organic amendment, i.e., moss and compost. Two-week-old seedlings were transferred to pots, and after 4 weeks, the bacterial strain was inoculated, then watered with synthetic wastewater for 5 weeks and harvested after 9 weeks. After harvesting, physiological and biochemical parameters, as well as metal contents of plants, were quantified. The results indicated highest growth and biomass production in moss- and compost-associated plants while highest metal uptake has been found in the presence of P. japonica and synthetic wastewater–irrigated plants. Synthetic wastewater–irrigated plants have shown highest Pb uptake of 2899 mg kg⁻¹ DW, while with P. japonica in soil those plants have shown highest Cd, Cu, Ni, and Cr uptake of 962, 1479, 1042, and 956 mg kg⁻¹ DW, respectively. The production of antioxidant enzymes, i.e., catalase (CAT), ascorbate peroxidase (APX), guaiacol peroxidase (GPX), and glutathione-s-transferase (GST), was high in P. japonica–amended plants because of increased uptake of metals. It is concluded that moss and compost have improved growth while P. japonica improved metal accumulation and translocation to aerial parts with little involvement in plant growth.
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