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Temporal Monitoring and Effect of Precipitation on the Quality of Leachate from the Greater Casablanca Landfill in Morocco Полный текст
2022
Zaki, Khadija | Karhat, Youness | El Falaki, Khadija
A monthly temporal monitoring of the physico-chemical parameters of the leachate from the Greater Casablanca “Mediouna” open-air landfill in Morocco over a period of 13 months was carried out to show their variability over time. This monitoring also highlights the effect of rainfall on leachate quality through fluctuations observed in wet and dry periods. Indeed, the leachate was sampled from a collector that drains a mixture of young and mature leachate. Several physico-chemical parameters were studied: pH, temperature, conductivity, organic matter (BOD5 and COD), total matter (TS, TVS), nitrogen (N-NO2-, N-NO3-, N-NH4+, TKN), total phosphorus (Tp), salts (Cl-, SO42-) and metals (Cd, Co, Cr, Ca, Cu, Fe, K, Mg, Mn, Ni, Pb, Zn). As a result, significant concentrations were recorded throughout the monitoring for the majority of the parameters, showing a high aggressiveness of the leachate. Also, statistically significant relationships were observed between the different parameters. On the other hand, the leachate pollution index (LPI) was calculated to determine the overall potential of leachate pollution. The identification and study of the behaviour of the physico-chemical parameters is very useful for the design of an adequate leachate treatment plant for the Greater Casablanca landfill "Mediouna", taking into consideration the extreme values recorded during the monitoring period, in order to avoid any malfunctioning due to an underestimation of the pollution.
Показать больше [+] Меньше [-]Distribution Features of Microplastic Particles in the Bolshiye Koty Bay (Lake Baikal, Russia) in Winter Полный текст
2022
Karnaukhov, Dmitry | Biritskaya, Sofya | Dolinskaya, Ekaterina | Teplykh, Maria | Ermolaeva, Yana | Pushnica, Victoria | Bukhaeva, Lidiya | Kuznetsova, Iya | Okholina, Anastasia | Silow, Eugene
The problem of pollution of aquatic ecosystems with microplastics has been actively studied by the world scientific community. Most of this research has been devoted to marine ecosystems, whereas scant research has been conducted on fresh water bodies. Lake Baikal (Russia) is a unique natural reservoir. Previous studies devoted to the amount of microplastics in the waters of Lake Baikal were carried out singularly and were not of a systemic character; therefore, previously obtained data does not reflect a complete picture of the state of the lake. Within the framework of this study, our goal was to study the composition and morphological structure of microplastic particles in the ice of Lake Baikal at different distances from the coastline. To do this, a number of ice samples were taken from the upper and lower sides at five different points in South Baikal opposite the village of Bolshiye Koty. Later these samples were analyzed for the types of microplastics and their amount. In the samples taken, two types of microplastics were found—fragments and fibers—with fibers being predominant. The median values of the number of microplastics particles are higher in samples taken at the interface between water and ice, compared to samples taken from the ice surface. Presumably, main part of microplastic fibers found opposite the village of Bolshiye Koty were brought in by a constant circular current from the opposite east coast. In turn, the low number of fragments in the samples may be due to the freezing of the coastline.
Показать больше [+] Меньше [-]Assessment of Urban Growth and Variation of Aerosol Optical Depth in Faridabad District, Haryana, India Полный текст
2022
Ranjan, Kumar | Sharma, Vipasha | Ghosh, Swagata
Sustainable urbanization under sustainable development goals requires quantitative information on urban landscape. Despite having the fastest growth of urban area and poor air quality, Faridabad, a constituent district of National Capital Region, fails to gain much research attention. Present study based on multi-temporal; freely available satellite image has indicated 3% increase in the built-up against 2% decrease arable land from 2008 to 2018. Further, spatial metrics (Shanon’s entropy, class area (CA), number of patches (NP), largest patch index (LPI)) has indicated scattered development of built-up. Increase CA (11470 ha in 2008 and 13806 ha in 2018) and NP (221 in 2008 and 476 in 2018) have indicated isolated development of built-up with small area coverage. Increase in LPI (12.5% in 2008 and 13.5% in 2018) of built up indicated compact growth of dense built-up in the southern and eastern side leading to the vertical expansion of the city area. Linear expansion of the residential built-up, industrial, and commercial area along the highways, roads and railways and vehicular emission has contributed to the high aerosol concentration. While, in the rural region the high aerosol loading has also been observed because of the extensive use of fertilizer and stubble burning. Present research on land-use land cover changes and its impact on air quality could be contributed significantly in urban policy making for climate change adaptation and mitigation strategies.
Показать больше [+] Меньше [-]Analysis of Surface Water Quality using Multivariate Statistical Approaches: A case study in Ca Mau Peninsula, Vietnam Полный текст
2022
Giao, Nguyen Thanh
The study was conducted to assess surface water quality in Ca Mau peninsula using multivariate statistical analysis. Fifty-one water samples with the parameters of pH, dissolved oxygen (DO), total suspended solids (TSS), biochemical oxygen demand (BOD5), chemical oxygen demand (COD), ammonium (N-NH4+), orthophosphate (P-PO43-) and total coliform were used in the evaluation. Water quality is assessed using national standard and water quality index (WQI). The methods of cluster (CA), discriminant (DA), principal component analysis (PCA) were used to analyze the variation patterns of water quality. The surface water was contaminated with organic matters, suspended solids, nutrients, and microorganisms. DA revealed that DO, TSS, BOD5 and pH contributed 76.91% to the seasonal variation of water quality. Water quality is classified from bad to heavily polluted. CA grouped water quality into 7 clusters and DO, TSS, BOD5, COD and coliform of the clusters 1-3 were significantly higher than those of the clusters 4-7. PCA presented that PC1-PC3 was the main sources affecting water quality, explaining 85.45% of the variation in water quality. The sources of pollution can be human (domestic wastewater, waste from agriculture, fisheries, industry, landfills), natural (hydrological regime, rainwater overflow, river bank erosion). pH, DO, BOD5, COD, TSS, N-NH4+, P-PO43- and coliform have an impact on water quality and need to be continuously monitored. However, for the multivariate statistical method to be more effective, an initial data set with several water quality parameters sampling locations is needed. The current results provide scientific information and support local water quality monitoring activities.
Показать больше [+] Меньше [-]Air Pollution Tolerance Index (APTI) and Expected performance index (EPI) of Selected Plants at RGSC, (BHU), Mirzapur, India Полный текст
2022
M D, Anil | Pandey, Kumar | Krishna, Vijai | Kumar, Manish
This study carries the evaluation of tolerance of sixteen plants against pollution. These plants have been selected and assessed for several phyto-socio-economic (tree height, canopy, type of tree, laminar structure, hardiness and economic value) and biochemical qualities (pH, Relative water content (R), Ascorbic acid (AA), Chlorophyll a (Chl a), (Chl b), Carotenoids (Car) and total Chlorophyll (TC)) and tested for Air pollution tolerance index (APTI) and Expected performance Index (EPI) and then EPI score used as grades of plants (Not Recommended, Very poor, Poor, Moderate, Good, Very good, Excellent and Best Plus Plant). Statistical analysis tool like correlation matrix among plant parameters and ANNOA test has been applied to understand the relationship among plant parameters and plant species. The best EPI score means best suited plant for the area for plantation and green belt development while plant with lower EPI may be used as bioindicators for the pollution because they are very sensitive for the air pollution.
Показать больше [+] Меньше [-]Physico-Chemical and Microbiological Assessment of Soils from Dumpsites for Plastic Degrading Microorganisms Полный текст
2022
Emmanuel-Akerele, Hilda Abiola | Akinyemi, Priscilla Oluwatomi
Plastic pollution is a threat to the environment because of its slow degradation rate and high usage. The aim of this study is to isolate plastic degrading microorganisms from soils. The soil samples used for this study were collected from dumpsites filled with plastic and plastic materials and the effectiveness of the degradation of plastic materials was studied over a period of six (6) weeks in broth and agar culture under laboratory conditions by weight determination method. Physicochemical and microbiological analysis was carried out on the various soil samples using standard protocols. The biodegradation of polyvinylchloride (PVC) was done in-vitro using the microorganisms isolated from the soil. Microorganisms that were able to degrade a higher percentage of the plastic materials were; Staphylococcus aureus, Streptococcus sp, Bacillus sp, Escherichia coli Aspergillus niger, Aspergillus flavus and Trichoderma viridae. The total viable count for bacteria and fungi were within the range of 11.8x105 CFU/g to 2.0x1010 CFU/g and 3.3x105 CFU/g to 0.1x1011 CFU/g respectively. Staphylococcus aureus, Streptococcus sp, Bacillus sp, Micrococcus sp, Aspergillus niger, Aspergillus flavus, and Trichoderma viridae, degraded plastic up to 25%, 31.2%, 25% 31.2%, 12%, 10% and 10% respectively. These isolates may be used to actively degrade plastics, thereby reducing the rate of plastic pollution in our ecosystem.
Показать больше [+] Меньше [-]Household Dust from a City in Morocco: Characterization by Scanning Electron Microscopy Полный текст
2022
Bouchriti, Youssef | Kabbachi, Belkacem | Ait Haddou, Mohamed | Achbani, Abderrahmane | Amiha, Rachid | Gougueni, Hicham
Exposure to household dust is a common occurrence in all countries and causes various diseases. This study provided information on the number, shape, size distribution, and elemental composition of household dust particles collected in urban homes in Agadir city in Morocco. Moreover, a potential human health risk of exposure has been identified based on current research. Samples were analyzed using computer-controlled scanning electron microscopy and ImageJ image processing program. A total of 3296 particles were analyzed for their size, and 76 particles were classified according to their size and elemental composition. Household dust particles were classified in six types: micro-aggregates (31.6%), biogenic (5.3%), spherical (17.1%), subrounded (7.9%), subangular (11.8%), and angular (26.3%). These particles were determined to have originated from a distant source (Trask classification index between 1 and 2.5). They were large (Skewness asymmetry coefficient > 1), and ranged from 0.2 to 363 µm with an average value of 22.8 ± 0.6 µm in diameter. Dust particles with diameters of 5-10 µm and 10-20 µm were the most abundant, while dust diameters of 10-20 µm, 20-30 µm, and > 100 µm were the highest in volume. The domestic dust deposition rate was 19.8 ± 7.4 g/m2 per year. Household dust is one of the major sources of PM10 in the residential environment (44.6% of the total number of particles), and the studied properties of house dust are highly related to human health. Household dust is a critical element to be considered in the occurrence of respiratory and cardiovascular infections.
Показать больше [+] Меньше [-]Impact of Cobalt Oxide Nanoparticles Dispersed in Water in Diesel Emulsion in Reduction of Diesel Engine Exhaust Pollutants Полный текст
2022
M. D., Anil | Hemadri, Vinayak | Swamy, Mrityunjaya
The present work is aimed at decreasing pollutants emitted by diesel engine exhaust tailpipe and enhancing performance by incorporating cobalt oxide nanoparticles in water emulsified diesel. Water concentration of 5% and 10% is used to prepare various WD emulsion blends, with nano particle dosage levels of 50PPM and 100PPM. High speed homogenizer and ultrasonicator devices are used to disperse water droplets in diesel. Surfactant mixture of span80 and tween20 is used to achieve long term stability of emulsified fuel. The functional groups of emulsified fuel are analysed using FTIR spectroscopy. The characterization of cobalt oxide nanoparticles is carried using scanning electron microscope. Physiochemical properties such as calorific value, density, viscosity of emulsion blends and pure diesel are determined and compared. Experimental results reveal that addition of cobalt oxide nanoparticles in emulsified fuel with increased dosage of 100PPM shows 23%, 33.3%, 25%, and 44.6% reduction in NOX, HC, CO and smoke emission compared to pure diesel. The improvement in BTE and BSFC were observed for all emulsion blends.
Показать больше [+] Меньше [-]Myco-remediation of Dairy Wastewater by Naturally Attenuated Aspergillus sp. Responsible for Sulfate Reduction Полный текст
2022
Sharma, Neha | Meher, Alok Kumar | Bhagwani, Harshita | Chahar, Darshan | Yadav, Neetu | Kohli, Vipra | Shourie, Bhavyam | Arunachalam, Kalirajan | Siankuku, Munaska
Dairy industries generate enormous volumes of waste water which are significantly rich in organic compounds; contributing to high BOD, COD and sulfates. As a mandate to ‘treat’ effluents generated by different unit operations in a dairy industry, current treatment methods rely on physico-chemical, mechanical and conventional biological interventions. This approach remains unviable because of cost intensiveness and excessive energy usage. Additionally, the significant lowering of pollution indicators remains a daunting task with inlet and outlet parameters. With these identifiable gaps, our study was aimed to screen bio-efficacious, naturally attenuated fungal isolates to lower exceeding levels of sulfate in effluents released by dairy industry. Effluent samples were collected from Effluent Treatment Plant (ETP) of Jaipur Dairy, Rajasthan Dairy Co-operation Limited (RCDF), Jaipur. For mycological investigations, qualitative screening was carried out in Potato Dextrose Agar (PDA) supplemented with Calcium Sulfate (CaSo4) (0.1g/L). The most promising fungal isolates belonging to Aspergillus sp. was characterized based on its cultural and microscopic characteristics. Microcosm study was conducted by supplementing Aspergillus sp. in Untreated Dairy Effluent (UDE) for a period of 7 days at Room Temperature (RT) under static conditions. Following the incubation phase, mycelial mesh (plug) was indicative of exponential fungal growth. Effluent seeded with Aspergillus sp. and abiotic controls were spinned at 5000 rpm for 15 minutes to eliminate biomass. Sulfate estimation was carried out in Cell Free Extract (CFE) of both experimental and control group. A significant reduction of 67.3% was observed (p<0.05) with respect to positive control and 8.4% when contrasted with abiotic control.
Показать больше [+] Меньше [-]Potential Application of Synchronous Fluorescence Spectroscopy to Identification of PAHs in Airborne PM2.5 Полный текст
2022
Sharma, Homdutt | Jain, Vinod Kumar | Khan, Zahid Husain
A simple and rapid method for the highly sensitive determination of polycyclic aromatic hydrocarbons (PAHs) from airborne fine particulate matter (PM2.5) in an urban environment of Delhi was developed. The target compounds were 10 of the 16 United States Environmental Protection Agency (US-EPA) priority PAHs: fluoranthene, pyrene, chrysene, benzo(a)anthracene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo[a]pyrene, dibenzo(ah)anthracene, benzo(ghi)perylene, indeno(1,2,3-cd)pyrene. For collecting the samples, the following two locations in Delhi (India) were chosen: ITO and Okhla Industrial Area. Two sets of samples at these locations of were collected for the purpose of investigation. The fine particulate matter samples were collected on glass fiber filter papers for 24h, from which the PAHs were extracted using dichloromethane (DCM) and hexane using ultrasonication method. Comparison of the characteristic emission of spectra of PAHs with standard spectra indicated the degree of condensation of aromatic compounds present in the investigated mixtures. However, this identification could be more effective with the use of the respective values of Δλ parameter for each particular component of the mixture. It has been found that the concentration of the PAHs is maximum during the winter season and minimum during the summer and monsoon seasons at both the locations.
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