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Studying Some Blood Parameters of Otolithes ruber (Schneider, 1801) in Cold and Warm Seasons as an Indicator of Pollution in Musa Creek
2021
Ghasemi, Hamideh | Abdi, Rahim | Doraghi, Abdulmajed | Salamat, Negin | Salari-Aliabadi, Mohammad Ali
The present study attempts to investigate some blood parameters of Otolithes ruber during different seasons in terms of both temperature and pollution. For so doing it uses 10 specimens, for each station and season, collected from 5 polluted stations, including Petrochemical, Ghanam, Zangi, Douragh, Patil, and Sajafi as the control group, away from pollution in Musa Creek. The fish are anesthetized with 1ml of clove extract per liter. Their blood samples are taken immediately from the caudal vein, using a heparinized syringe. Afterwards, the serum is separated in a centrifuge with a speed of 6000 rpm for 2 minutes. The desired factors are measured by the Mindray BS200 auto-analyzer and the total protein level, by Bradford's usual laboratory methods. Results show that AST, ALT, ALP, Glucose, and Triglycerides have increased in more polluted stations (P≤0.05). In sheer contrast, total protein and Albumin have decreased as pollution grows (P≥0.05). According to this study, environmental water pollution of the fish has a large impact on the concentration of measured blood parameters, whereas the influence of seasonal changes on most of them is low.
Mostrar más [+] Menos [-]Batch and Column Studies on Nickle and Cadmium Removal Using Iranian Clay-based Geopolymer
2021
Bakhtiari, Somayeh | Zeidabadinejad, Asma | Abbaslou, Hanieh | Ghanizadeh, Alireza
The production rate of industrial and agricultural waste is increasing due to population growth. Soil is the most important receiver of industrial and agricultural waste. Contaminants such as heavy metals in various waste after reception by the soil, immediately become part of the cycle that has different impacts on the environment. Geopolymer, as a chemical stabilizer has the potential to stabilize heavy metals in the soil. In this research, several geopolymers for the stabilization of heavy metals in soil were synthesized. Silicon dioxide (SiO2) and aluminosilicate (Al2SiO4) must be used to produce the geopolymers. Rice husk ash was used as the SiO2 source. Also, Iranian zeolite and sepiolite, and red clay soil were utilized as the source of Al2SiO4. The synthesized geopolymers were investigated for the adsorption of nickel and cadmium. Also, batch and column studies of using geopolymers for the chemical stabilization of heavy metals in soil were conducted. The results revealed a high adsorption capacity of the geopolymers. The zeolite, sepiolite, and red clay geopolymer-soil samples adsorbed 100% of the heavy metals (i.e., Ni and Cd) at a concentration of 100 ppm. The zeolite geopolymer adsorbent adsorbed 57% and 96% of Ni and Cd at a concentration of 1000 ppm, respectively. In general, it was concluded that the use of geopolymer compounds in soils with high heavy metal adsorption capacity could be an efficient approach to prevent groundwater resource pollution.
Mostrar más [+] Menos [-]Extraction of Keratin from Human Hair Waste as Adsorbent: Characterization, Thermodynamic and Kinetic Study for Removal of Chromium (VI) ions
2021
Abbasi, Fereshteh | Farrokhnia, Abdolhadi | Abbasi, Zahra
In this paper, human hair, as a waste material, was utilized in order to prepare keratin nanoparticles. The characterization of keratin nanoparticles was performed applying Transmission electron microscopy (TEM), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR) and X-Ray diffraction (XRD). The average diameter of keratin nanoparticles was found to be 63.7 nm, using particle size analyzer. Subsequently, the keratin nanoparticles were employed for Cr (VI) ions adsorption. The batch experiment was carried out to find the optimum conditions; i.e. contact time, pH, adsorbent dose and initial concentration of Cr (VI) ions. The adsorption capacity was extremely pH-dependent, and the maximum adsorption of Cr (VI) happened in the acidic pH range. The results demonstrated that the maximum adsorption capacity, obtained in acidic pH, was 161.29 mg/g. The equilibrium data were well fitted by Freundlich isotherm. The kinetic studies were performed with the Lagergren’s first-order, Pseudo-second order, Elovich, and Intra-particle diffusion models. In this sense, in order to describe kinetic data, we came to this understanding that Pseudo-second order model was the best choice. The thermodynamic parameters of the adsorption process indicated that the Cr (VI) adsorption on keratin nanoparticles is endothermic and spontaneous.
Mostrar más [+] Menos [-]No Seasonal Differences in the Emission of Microplastics from an Urban Wastewater Treatment Plant on the Southern Coast of the Caspian Sea
2021
Alavian Petroody, Somayye Sadat | Hashemi, Seyed Hossein | van Gestel, Cornelis A.M.
This paper is the first to report on the role of a wastewater treatment plant (WWTP) in Sari, as a source of microplastics (MPs) in the Caspian Sea. Composite 270-liter/24-hour samples were taken the treated effluent of the WWTP in winter and spring, two seasons with different levels of human activity. The effluent contained 380±52.5 and 423±44.9 MPs/m3 in winter and spring, respectively, with the total numbers of MPs/m3 not differing between the two seasons. The dominant type of MPs in the effluent was microfibers with 237±68.7 and 328±33.4 per m3 in winter and spring, respectively. In both seasons, fiber sizes of
Mostrar más [+] Menos [-]Water Quality Assessment in Urban Wetlands and Suitability for Fish Habitat: A Case Study
2021
Dixit, Arohi | Siva Siddaiah, Neelam | Singh Chauhan, Jogindar | Ullah Khan, Waseem
In this study, water from three urban wetlands of Gurugram – Sultanpur (WS), Damdama (WD), and Basai (WB), was studied for various physicochemical parameters to assess their suitability for the healthy survival of fishes and the results were compared with the limits of these parameters for fish farming. The parameters studied were colour, temperature, pH, alkalinity, hardness, Ca2+- Mg2+ ratio, NO3-, Cl-, SO42-, PO43-, and heavy metals (Fe, Mn, Cr, Cu, Zn, Ni and Pb). The results of the study indicate the majority of studied parameters are beyond the desirable limits in WB; thus, water is most unsuitable for fishes in WB. WB is unsuitable for parameters: colour, alkalinity, hardness, Ca -Mg ratio, NO3-, Cl-, SO42-, PO43-, Cr, Cu, Fe, Mn, Ni and Zn. WS needs consideration for temperature, NO3-, Cu, Ni and Zn, whereas WD needs improvement in temperature, TDS, NO3-, Cr, Cu, Fe, Mn, Ni and Zn concentration for better fish growth. Most of the parameters are high in summer as compared to winter, which is due to the dilution after rainfall. Hence, we recommend timely action for effective measures to improve the water quality of wetlands and their regular monitoring for improved fish habitat.
Mostrar más [+] Menos [-]Assessment of Groundwater Based Public Drinking Water Supply System of Kamrup District, Assam, India using a Modified Water Quality Index
2021
Goswami, Jayanta | Bhattacharjya, Rajib Kumar
This work aims to assess the Water Quality Index (WQI) of the groundwater-based public drinking water supply system of Kamrup District (Rural) of Assam, India. For assessing WQI, water samples have been collected, both raw water and treated water, from seventy-eight public drinking water supply projects over the district for comprehensive physicochemical analysis. The WQI was calculated based on the weightage derived from the literature survey and based on the doctors’ weightage. The derived WQI showed that the water quality falls from poor to very poor quality. However, the concentration of the water quality parameters except Iron, Fluoride, and Manganese are within the permissible limit in all the water supply projects. It shows that the WQI calculated based on the weightage derived, as stated above, is not displaying the actual water quality of the supplied water. As such, a modified method is proposed to calculate the WQI of the supplied water considering the permissible limit of the parameters in deriving the weightage for the parameters. The WQI values calculated using the modified method falls in the range of good water quality to poor water quality and shows the true water quality of the supplied water. The statistical analysis of the water quality parameters and WQI shows that the WQI has a very high correlation with Manganese with a coefficient of correlation value of 0.86, followed by 0.4 with Chloride and 0.34 with Fluoride.
Mostrar más [+] Menos [-]Trace Metals Distribution and Fractionation in Soils Around the Abandoned “Ichmoul” Pb-Zn Mill-Mine, North-East of Algeria
2021
Bouzid, Khadidja | Boutaleb, Abdelhak | Toumi, Mohamed
In order to assess the environmental impact of soil polluted with trace metals, representative soils were collected surrounding the abandoned Pb–Zn mine mill (SM soils), and the new temporary ore storage site (SS soils), which are located in the vicinity of Medina (Aures), North-east of Algeria. Total digestion has been used to determine the total content of Zinc, Copper, Lead, Cadmium, and Arsenic, then it was analysed by inductively coupled plasma atomic emission spectrometry (ICP-AES). The sequential extraction Tessier scheme was also used to extract the chemical forms of Zn, Cu, and Pb, and their concentrations in each fraction were analyzed by atomic absorption spectrometry. Lead was the most abundant trace metals, its concentration in mg.kg-1 ranged between (67.20 – 46000), followed by Zinc (26 - 1853), Copper (32 – 495), Arsenic (8 – 116), and Cadmium (0.3 - 7.30). Sequential extraction shows that Zinc was mainly associated with reducible and residual fractions. Copper was bound predominantly with the minerals in the residual fraction, followed by the organic matter. Lead was bound mainly with carbonate fraction in SM soils, while Pb in the SM soils was mainly associated with the reducible fraction. The Pb, Zn, Cu mobility factor was significantly higher in SM soils than in SS soils. These results indicate that anthropic activities related to ore concentration and mining process lead to increased concentration of trace metals in surrounding soils, hence their mobility and bioavailability, this consists a potential risk to the environment and biota.
Mostrar más [+] Menos [-]Sustainability-based Conservation Approach to Assess the Health and Quality Condition of Aquatic Ecosystems using bed Sediment Oxygen Demand Rate and its Associated Factors (Case study: Darreh-rood River, Aras Basin, Moghan Region, NW-Iran)
2021
Ashayeri, Azim | Mehrdadi, Nasser | Nabi Bidhendi, Gholamreza
Bed Sediment is a dynamic and complex material that plays an important role in the aquatic ecosystems and provides habitat from a highly various community of organisms. To address the major issue, this study, which its substantive subject done for the first time in Iran, aimed to assess the current status of Darreh-rood river's health and quality using SOD rate and its associated factors including Texture, fine-PSD, TOC and TP of bed sediments along with some basic field parameters of river-water. All required samples were collected from 10 sampling points in due course. SOD data with regard to related factors were calculated and analyzed. The rates of SOD ranged from 0.69 to 1.57 g O2/m2/day. Moreover, this index was classified in varied quality domains. Afterwards, a predictive equation was determined among SOD rate and its associated parameters using MATLAB software. Finally, the Results showed that the river quality and health suitability in research area are in categories slightly clean and slightly degraded, in targeted zones during the study period. Also, the increase in TOC and TP concentrations together with a decrease in sediment particle size was led to an increase in SOD-rate accordingly. In conclusion, the consequences of this study under Survivability-based Adaptive Management (SAM) perspective can be used as a rapid diagnostic tool to support water policy decision-makers and other stakeholders to promote the best practices for protecting the health conditions of riverine systems, focusing on selecting the appropriate points for discharging the wastewaters into the receiving water-bodies.
Mostrar más [+] Menos [-]Examining the Environmental Kuznets Curve in Sweden to Assess the Nexus of Economic Sectors
2021
Pakrooh, Parisa | Brännlund, Runar
To support the fulfillment of Sweden’s targets in term of climate change and economic growth, we need to do a distinct study to show the Environmental Kuznets Curve (EKC) pattern in different sector of the economy, as the GDP allocation, energy intensities, GHG emission, and technological development are different between sectors. This kind of study helps to figure out how the different sectors contribute to climate change and could appoint more particular and effective environment-energy policies. For this aim, we analyzed the existence of the EKC by implementing the ARDL Bound test approach in the whole and individual sectors of Sweden’s economy throughout 1990-2019. Our results indicated the contribution of a particular sector on total GHG emissions per capita. Results of the whole economy confirmed the EEKC hypothesis with a turning point in 1996, in which the AFF sector, unlike industry and service, had increased GHG emissions. Disaggregated sectoral analysis showed various results. The industry sector had efficient energy improvement. Policymakers should pay attention to AFF’s GHG emissions, as different sources of energy consumption had not impressive impact in both the short and long term. Also, effective fossil-related policies are necessary for the service sector due to the main contribution to transportation.
Mostrar más [+] Menos [-]Investigation of Suspended Particle Concentrations (PM10, PM2.5, TSP) in Tehran Subway Line one Stations in the Spring and Autumn
2021
Mousavi Fard, Zahra Sadat | Asilian Mahabadi, Hassan | Khajehnasiri, Farahnaz
Today, indoor air pollution is a major concern. So far, many quantitative and qualitative studies have been conducted on particulate matter pollution in closed environments, but not much research has been done to measure air pollution in subway station. In this study, we have investigated the concentrations of PM10, PM2.5 and TSP particles in 12 underground stations on the oldest and main Tehran metro line, in two seasons, autumn and spring. For sampling suspended particles, we have used a portable direct reading device for monitoring suspended-particles (HAZDUST EPMA5000). We also used Pair T- test to compare the particle concentrations in different modes of the ventilation system (on, off, and inlet air) and Three-way variance analyze. According to the results, the mean concentrations of PM2.5-PM10 - TSP values in line-1 on the station platforms are significantly higher in spring than in autumn, off state of the ventilation system than on state of the ventilation system (P <0.001). Also, the concentration of particles measured in the air of subway stations is higher in the off state of ventilation systems, compared to Inlet air to stations (P<0.001). There is a correlation between concentration of particles measured in different sampling season, condition of the ventilation mode (on, off, inlet air) (P<0.001). Improving the efficiency of ventilation systems (equipped with a suitable filter) and fan in stations is suggested as one of the factors to reduce the concentration of particles, especially in spring.
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