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Biomonitoring of Water Bodies in Metro Manila, Philippines Using Heavy Metal Analysis and Erythrocyte Micronucleus Assay in Nile Tilapia (Oreochromis niloticus) Texte intégral
2019
Zeba F. Alam, Charilen Kei V. Concepcion, Johnray D. Abdulrahman and Miguel Alvaro S. Sanchez
Environmental biomonitoring of water bodies is routinely done to assess the ecological state of aquatic systems by detecting the hazardous and genotoxic pollutants. In this study, a combination of atomic absorption spectroscopy and the fish micronucleus assay was used to determine and compare the genotoxic potential of water bodies specifically the two Esteros namely, Estero de Vitas and Estero de Paco, which are part of the Pasig River System, Philippines. As part of the strategy, the Esteros are being rehabilitated to control pollution in the river systems whereby Estero de Paco was recently rehabilitated, whereas, Estero de Vitas is still largely neglected. The elevated levels of micronuclei and nuclear abnormalities were observed in the erythrocytes of the genetic model, the Nile tilapia (Oreochromis niloticus) exposed to water samples from the two sources tested when compared to a control group indicating the presence of genotoxic and hazardous pollutants in the water bodies of Estero de Paco and Estero de Vitas. Further, the water samples from Estero de Vitas were found to be far more genotoxic as compared to the water samples from Estero de Paco (p<0.05). The observed genotoxic effects of the water samples appeared to be related to the physico-chemical characteristics studied using atomic absorption spectroscopy, which showed the presence of heavy metals in the water samples from both the sources. The AAS results also confirm the presence of heavy metals in the fish tissue exposed to the water samples from the two locations. Hence, the tilapia fish (a component of Filipino diet) should be consumed with precautions as it can absorb the heavy metals present in ecosystems. The results establish that the fish micronucleus test is an effective assay for environmental biomonitoring. The lower genotoxicity potential of Estero de Paco clearly demonstrates that the restoration of the Esteros can be an effective approach to control pollution of the water bodies, especially the Pasig river system.
Afficher plus [+] Moins [-]Vertical Distribution of Microplastics in Coastal Sediments of Bama Resort, Baluran National Park, Indonesia Texte intégral
2019
Muhammad A. Asadi, Yody A.P. Ritonga, Defri Yona and Asus M.S. Hertika
Microplastic pollution is widely reported in different marine environments from shorelines to seabed of deep seas which pose an emerging threat to entire marine ecosystems. As the world’s secondlargest microplastics polluter, an understanding of the distribution of this type of pollution is important for the measurement of the magnitude of environmental risk. In the present study, the abundance and distribution of microplastics in coastal sediments of Bama Resort, Baluran National Park were measured at depths of 0-10 cm, 10-20 cm, and 20-30 cm. Microplastics characterization was performed using a modified flotation method while a sieve analysis was used to assess the particle size of the sediments. Results showed that there were 484 particles with a total average abundance of 116.41 ± 80.78 particles kg-1 DW. Fibres shared 37.8% of the total microplastics found with overall average of 43.71 ± 36.52 particles kg-1 DW. Overall, Tukey’s multiple comparisons test showed significant differences (P< 0.01) in vertical distribution of microplastics in which 55.46% of particles were found at the depths of 0-10 cm, whereas at the depths of 20-30 cm, the proportion was only 15.95%. There were two types of sediments, sandy gravel and gravelly sand in which the former type of sediments holds higher microplastic particles due to its grain dominance in upper sediments. These results imply that microplastics pollute coastal sediments of Bama Resorts, BNP, and their deposition increase over time as greater microplastics frequencies were observed in upper and more recent sediment.
Afficher plus [+] Moins [-]Estimation of Wood Residues Generation from Sawmilling Activities and Energy Potential in Kwara State, Nigeria Texte intégral
2019
E. A. Alhassan, J. O. Olaoye, T. A. Adekanye and C. E. Okonkwo
The global concerns about the rise in anthropogenic gases have resulted in alternative clean energy sources. Biomass is one of the most prominent renewable energy sources, which can be found in wood and wood wastes, agricultural crops and their waste byproducts, municipal solid waste (MSW), animal wastes, food processing, aquatic plants and algae. Wood and by-products obtained from forest biomass stand at the centre of Renewable Energy Source (RES) due to its availability and usefulness in most developing countries. Sawdust is one of the wood processing residues that is in excess of local demand because of the near absence of its industrial demand in Kwara State. Data relating to its availability, industrial usage and energy potential are rarely available in this study area. This study investigates its availability and inherent energy potential that can be a vital tool for energy policy, planning and development. Wood wastes generated in the state were estimated to be 8012.8 m3/yr with inherent energy potential of 31298 GJ. By putting sawdust, seen as wastes in most wood processing plants, into efficient use will help reduce the competition for wood as a source of heat for cooking and heating.
Afficher plus [+] Moins [-]Simultaneous Reduction of Smoke and NO Emission Using Lower Order Alcohols in a Jatropha Methyl Ester Fuelled Compression Ignition Engine Texte intégral
2019
Venkatesan Rajasekar, Varuvel Edwin Geo, Leenus Jesu Martin and Beddhannan Nagalingam
The objective of this work is to experimentally study the consequence of blending lower order alcohol (methanol and ethanol) with jatropha oil methyl ester (JOME) in a single cylinder, four stroke and watercooled CI engine. 70% JOME blended with 30% methanol (J70M30) and 70% JOME blended with 30% ethanol (J70E30) are the two blends prepared to operate the engine. Experiments were conducted from 0 to 100% load at a fixed engine speed of 1500 rpm and the results were compared with base fuels. Due to the inferior physical properties of JOME, brake thermal efficiency (BTE) decreases compared to diesel at maximum load. Also, NO emissions increased by 4% and smoke opacity decreases by 10% while operating the engine with JOME compared to diesel. Simultaneous reduction of NO and smoke is achieved by blending lower order alcohol with JOME and a slight improvement in BTE is observed.
Afficher plus [+] Moins [-]Antibiotic Resistance of Pseudomonas aeruginosa in Well Waters in Irrigated Zone (Middle Atlas-Morocco) Texte intégral
2019
Fatima Zahra Hafiane, Latifa Tahri, Najia Ameur, Rajaa Rochdi, Karim Arifi and Mohammed Fekhaui
Pseudomonas aeruginosa is a bacteria which can live in freshwater, soil and plants. It is a commensal of the digestive tube, slightly abundant in human body. Its presence in wells water is a result of current anthropogenic activity and pollution loads. It is an important nosocomial pathogenic agent characterized by an intrinsic resistance to multiple antimicrobial agents which can develop high-level multidrug resistance. To assess the contamination of these well waters by this pathogenic germ, two hundred samples were collected for four seasonal campaigns between March 2017 and May 2018 with a rate of forty three (43) samples per season in an irrigated zone. The samples were analysed to identify P. aeruginosa, then the isolated serotypes were determined by slid agglutination test using four pools and 20 monovalent Antisera. The detected P. aeruginosa were tested for susceptibility to 18 antibiotics. A total of (n=85/139) isolated strains were identified as P. aeruginosa representing 61.15 % of prevalence among Pseudomonas spp. Antimicrobial resistance revealed that 68% of them are multidrug resistant, while15.09 % of strains resist at least to 7 antibiotics, 30.19% resist at least to 11 antibiotics, 13.21% resist at least to 12 antibiotics, 5.66% resist at least to 13 antibiotics, and 3.77% resist at least to 14 antibiotics. The high level resistance of P. aeruginosa is observed with piperacillin tazobactam (100/10μg) (84.91%), ciprofloxacin (5μg) (79.25%), imipenem (10μg) and ceftazidime (30μg) (37.58%). The resistance of phenotypes of P. aeruginosa strains allowed to identify (n=20/85) ESBL, (n=31/85) oxacillinase broad spectrum ES-OXA, (n=5/85) phenotype of impermeability to imipenem, (n=12/85) cephalosporinase AMPC, and (n=17/85) wild type. The results showed the high antibiotic resistance levels of P. aeruginosa strains from well water samples against antibiotics. Furthermore, based on the results, these well waters can be a source of P. aeruginosa and human and animal susceptibility to other opportunistic pathogens.
Afficher plus [+] Moins [-]Diversity and Seasonal Variations of Plankton Communities After Major Flash Flood in the River Mandakini of Garhwal Himalaya Texte intégral
2019
Deepak Singh and Gunjan Goswami
Plankton diversity acts as an ecological indicator of aquatic ecosystems due to their rapid response to environmental changes. Plankton samples were collected monthly for a period of 24 months. A total of 35 genera of phytoplankton belonging to three classes, Bacillariophyceae (21 genera), Chlorophyceae (9 genera) and Cyanophyceae (5 genera) were found. The abundance of phytoplankton was in the order, Bacillariophyceae (83%) followed by Chlorophyceae (9%) and Cyanophyceae (8%). Maximum phytoplankton density in winter season was attributed to the low water temperature, gentle water velocity, high transparency, availability of sufficient nutrients and most stable substratum. Eight genera of zooplankton belonging to three major groups, Protozoa (2 genera), Rotifera (5 genera) and Copepoda (1 genus) was recorded. Shannon-Wiener diversity index of phytoplankton and zooplankton was computed maximum to be 2.61 and 1.56 respectively in the winter season. PCA indicates Cymbella, Navicula, Synedra, Cocconeis, Achnanthidium, Amphora, Nitzschia, Tabellaria, Fragilaria, Ulothrix, Spirogyra and Phormidium to be most dominant genera in the Mandakini river. Total alkalinity, water temperature, transparency, velocity, dissolved oxygen, free carbon dioxide, turbidity, phosphate and nitrate were found to be the most important factors affecting plankton diversity in the Mandakini river.
Afficher plus [+] Moins [-]Preparation of New Surfactant and Study on its Application in Ultra-low Emission of Flue Gas Texte intégral
2019
Zhang Lei, Jia Yang, Zhang Lei, Zeng Tianyou, Wen Xin and Kong Tingting
In this paper, with different types of optimal surfactant monomers and potentiators mixed, the optimum formula of the new surfactant was obtained. The new surfactant with low toxicity, low cost and good dust removal effect was developed by the simulated flue gas experiment and verified the removal efficiency of the new surfactant on the particulate matter in the flue gas. It provided a reference for the industrial application in ultra-low emission of coal smoke. The results showed that the new surfactant could effectively reduce particulate matter in the simulated flue gas, and be the best to the dust particle size less than or equal to 1 micron. The optimum formula was worked out to be: anionic surfactant sodium dodecylbenzene-sulfonate (SDBS) 0.06%, anionic surfactant rapid penetrant T 0.06% and inorganic salt NaCl 1%.
Afficher plus [+] Moins [-]Detection of Sewage Discharge by Density Peak Search and Differential Expression Analysis Texte intégral
2019
Weiguo Sun, Xudong Zhao and Hong Chen
Nowadays, water pollution is a part of the major environmental problems. Industrial sewage that does not meet the emission standards will pollute the surface water and groundwater when it is discharged into water bodies, causing serious adverse impacts on human beings and environment. In view of industrial sewage privately discharged without properly monitoring, we present a method for detection of sewage discharge using clustering and differential analysis on image sequences derived from satellite photos taken when focusing on a certain place. The proposed method helps to indicate key images containing sewage, make the sewage area and leave evidence for the retrospective incident. Clustering based on the search of fast density peaks is used for detecting images containing sewage. In addition, two sample’s t-test and Fisher linear discriminant analysis are combined to extract the key pixels representing the area of sewage discharge. Experiments were made on 200 images corresponding to a certain area at different times of the day and 25 key frames with areas labelled to be sewage discharge were extracted, which indicated the effectiveness of this method.
Afficher plus [+] Moins [-]Degradation of Dye C.I. Reactive Red 15 in Aqueous Solution by Kaolinite Supported Zero Valent Iron Texte intégral
2019
Sheng Fang, Ningcan Yang, Muqing Qiu and Chengcai Huang
Dyes are important source of water pollution and their degradation products may be carcinogens and toxic to mammals. For evaluation of oxidative degradation of dye wastewater, the kaolinite supported zero valent iron were synthesized. The surface morphology of kaolinite and kaolinite supported zero valent iron were observed with scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The degradation of dye C.I. Reactive Red 15 in aqueous solution by kaolinite supported zero valent iron was investigated in details. The effects of the dosage of kaolinite supported zero valent iron, pH in solution, reaction time and the initial dye concentration on the degradation were studied. The results showed that the pH value, the dosage of kaolinite supported zero valent iron and the initial dye concentration had an important impact on dye degradation. Under these conditions, such as 80 mg/L dye C.I. Reactive Red 15, 20 min of reaction time, 0.5 g kaolinite supported zero valent iron particles, pH value of 2.0, temperature of 308 K and 120 rpm respectively, the degradation rate of dye C.I. Reactive Red 15 reached 82.3%.
Afficher plus [+] Moins [-]Energy Efficiency and Energy Conservation in China’s Transportation Industry: A Three-stage Data Envelopment Analysis Approach Texte intégral
2019
Cheng Zhang and Zhaoyu Yu
China’s transportation industry holds high energy consumption. The energy consumption of China’s transportation industry climbs up gradually with progress in urbanization and growing volume of passenger and freight traffic, which causes heavy environmental pollution. Improving energy efficiency is an important factor and management goal that influences the sustainable development of the transportation industry. In this study, an energy efficiency evaluation system of transportation industry was initially constructed, and the three-stage data envelopment analysis (DEA) model was adopted to estimate the energy efficiency of China’s transportation industry during 2001-2016. Subsequently, environmental variables were introduced to further perfect the calculation results. Results demonstrate that the technical efficiency (TE) of China’s transportation industry is 1 in 6 years during the study period in the traditional DEA model, reaching the technological frontier level. TE still has a large potential for improvement. The input redundancy of energy efficiency in China’s transportation industry may increase as per capita gross domestic product increases. However, such input can be effectively decreased by increasing the total export-import volume and total retail sales of consumer goods. After eliminating environmental and random factors, the low energy efficiency of China’s transportation industry is mainly caused by scale inefficiency. Conclusions in this study can provide theoretical references to understand and improve the energy efficiency of the transportation industry and thus formulate effective transportation energy and environmental policies.
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