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Monitoring Methods of Marine Pollution Range Based on Big Data Technology Texte intégral
2021
Q. Zhong and X.M. Liu
With the development of big data technology, traditional monitoring methods for the scope of marine pollution can no longer meet the current needs of accuracy and timeliness. In light of the outstanding topic, this study proposed to use big data technology to monitor the scope of marine pollution. The intelligent digital remote sensing technology was used for multi-dimensional monitoring of ocean water quality and completed the calculation of data collected by water quality sensors through the improved big data comparative analysis method. Finally, the scope of pollution monitoring was realized. The results verified that the proposed monitoring method could achieve high-precision and time-sensitive monitoring of the range of marine pollutants, and could identify the basic information of pollutants.
Afficher plus [+] Moins [-]Environmental Efficiency of Construction Industry with onsiderations to Carbon Emission: A Case Study in Henan, China Texte intégral
2021
Xin Youyang, Li Xiuzhong and Shang li
Low energy utilization is observed in China due to the extensive economic growth mode, which further leads to considerable energy wastes and environmental pollution. The construction industry plays an important role in the national economic development of China and consumes tremendous materials; thus, this industry discharges abundant CO2. The energy consumption growth rate of the construction industry in China is far higher than the national energy consumption growth rate, resulting in the prominent situation of high energy consumption and low yield. A case study based on Henan Province, China, was conducted to further analyze the environmental efficiency of the construction industry. An index system was established by using the Super-slack-based model (Super-SBM). This system chooses the following: labor, energy, capital, and technology of the construction industry as the input variables, economic output as the output variable, and carbon emissions as the unexpected output. This system was also used to investigate the energy efficiency of the construction industry in Henan Province from 2008 to 2019. Results demonstrated that the construction industry in Henan Province has failed to eliminate the extensive development mode thus far. The environmental efficiency of the construction industry presents a fluctuating growth with a mean of 1.048, which generally remains at a relatively low level. The numbers of construction machines and enterprises in the construction industry have redundancy in approximately 50% of the years. Thus, this study can provide some positive references to enrich the evaluation index system and estimation model of energy efficiency of the construction industry, which includes unexpected output. Moreover, the current study can provide a comprehensive understanding of the environmental efficiency of the construction industry in a province in China and realize reasonable allocation of construction industrial resources.
Afficher plus [+] Moins [-]Adsorption Behavior of Hydroquinone by Diatomite-based Porous Ceramsite Texte intégral
2021
Ruqin Gao, Lu Pan, Yingrui Huang, Zhaoyang Wu and Bingtao Liu
Diatomite-based porous ceramsite is a new kind of environmental material. In this study, ceramsite was prepared by wet grinding, a rolling-ball method, and high temperature-calcination using diatomite as the main raw material with the addition of a pore-forming agent and sintering assistant. X-ray diffraction, scanning electron microscopy, and mercury injection, were used to analyze the structure and characteristics of the prepared materials. Using hydroquinone as the target pollutant, the adsorption behavior of diatomite-based porous ceramsite was investigated. Results indicated that the diatomite-based porous ceramsite had a pore size ranging from 500 to 3000 nm, a specific surface area of 6.14 m2.g-1, and a porosity of 47.8%. When pH was 7, the removal rate and adsorption capacity of the hydroquinone by the diatomite-based porous ceramsite was 91.2% and 4.56 m2.g-1, respectively. In the adsorption process of hydroquinone by diatomite-based porous ceramsite, the diffusion of a liquid membrane was dominant, which could be better described by the quasi-first-order kinetic equation. The Langmuir and Koble-Corrigan equations had a higher fitting degree of data for the adsorption isotherms. The adsorption characteristics of the diatomite-based porous ceramsite are in accordance with the fixed-point adsorption of a single molecular layer and belong to a heterogeneous composite adsorption system. The correlation coefficient R2 and k value of hydroquinone adsorption by the diatomite-based porous ceramsite determined by the liquid film diffusion model were 0.848 and 0.0417, respectively.
Afficher plus [+] Moins [-]Advances in Microfiltration and Ultrafiltration Technology for Greywater Treatment: A Review Texte intégral
2021
Joaquin Ortiz
Advances in microfiltration and ultrafiltration technology for the treatment of greywater are important today because everything surrounding the use and preservation of water is an issue that increases in importance over the decades, and our planet will be seriously affected by the consequences of climate change, making water availability uncertain. Hence, wastewater recycling and its cyclical use have become a major topic in the scientific and engineering communities. The objective of this research is focused on compiling and updating all the advances in wastewater treatment, with emphasis on Greywater, in which components have a lower pollutant load than the rest of wastewater. In addition, microfiltration and ultrafiltration technologies were the technology selected to investigate in this investigation because they have the local potential for a second use of the wastewater before the discharge of contaminated water to the sanitation network. This research was carried out using words related to the exposed topic, such as “microfiltration”, “ultrafiltration”, “cleaning wastewater” and “greywater” in the search for documents in scientific search engines, selecting those that covered the topic and could be used to create this document. The results that were developed in this investigation, indicate that there is no generalized consensus on how to treat this greywater, nor how to qualify it. Additionally, it is important to note that despite the fact that urban greywater treatments have given good results, with the widespread use of bioreactors for this task, and the existence of various treatment alternatives for liquid waste that have shown good price-value ratio, studies related to greywater treatments using porosities are still in the incipient stages.
Afficher plus [+] Moins [-]Biosorption of Cu(II) from Aqueous Solutions by a Macrofungus (Ganoderma lobatum) Biomass and its Biochar Texte intégral
2021
Silin Yang, Yan Wang and Yungen Liu
The sorption capacities of the macrofungus viz. Ganoderma lobatum (C0) and its biochar (C400) were evaluated for the biosorption of Cu(II) from aqueous solution under different conditions, including adsorbent doses, pH of the solution, contact time and initial Cu(II) concentration. The results showed that Ganoderma lobatum could be used as an efficient biosorbent for the removal of Cu(II) ions from an aqueous solution. The desired biosorbent dose in the case of C0 and C400 for Cu(II) adsorption was 4 g/L, and the optimal pH value for biosorption was 8 for Cu(II). The Freundlich isotherm model fitted the absorption data of Cu(II) for both C0 and C400 better than the Langmuir isotherm model, and the adsorption capacity of C0 was better than C400. Our results indicate that C0 has a higher removal efficiency than C400 in adsorbing Cu(II) ions from aqueous solution. Biosorption kinetics were also studied using pseudo-first-order and pseudo-second-order models, which showed that the biosorption processes of Cu(II) ions based on C0 and C400 were in accordance with the pseudo-second-order kinetics.
Afficher plus [+] Moins [-]Evaluation of Fluoride Contamination Using GIS in Thirukkazhukundram Block, Tamil Nadu, India Texte intégral
2021
A. Amuthini Sambhavi, K. Nagamani and B. Gowtham
The presence of fluoride in the groundwater in the Thirukkazhukundram Block in south India is now becoming an increasingly alarming issue. With the semi-arid climatic conditions, charnockite and gneiss rocks form the basement, contributing to the geology of the study area. The pre-monsoon (August 2016) and post-monsoon (February 2017) fluoride concentrations have an average output of 1.3 mg.L-1 and 0.72 mg.L-1 respectively. As of date, only in Neikuppi, the fluoride contamination is found to be 2 mg.L-1 in pre-monsoon which is beyond the accepted limit as per the WHO standards. Other 29 locations taken up for study have fluoride value fluctuation from 1 mg.L-1 to 2 mg.L-1 in the pre-monsoon and from 0 to 1.5 mg.L-1 in the post-monsoon. The main factor responsible for this fluoride contamination lies in the study area’s hydro-geological condition which must be attended to immediately to prevent a public health problem in the future.
Afficher plus [+] Moins [-]Health and ecotoxicological risk assessment for human and aquatic organism exposure to polycyclic aromatic hydrocarbons in the Baiyangdian Lake Texte intégral
2021
Wang, Yizhen | Liu, Mingzhe | Dai, Yi | Luo, Yang | Zhang, Shilu
Seasonal and regional distributions of 17 polycyclic aromatic hydrocarbons (PAHs) in surface waters from four different main water functional regions of the Baiyangdian Lake were analyzed through GC/MS/MS during spring and summer season. The aim was to identify their possible pollution sources and evaluate their health risk for human and ecotoxicological risk for aquatic organisms. Results showed that the range of total PAH concentration is 35.38–88.06 ng/L (average 46.57 ng/L) in spring and 25.64–301.41 ng/L (average 76.23 ng/L) in summer. PAH contamination was observed slightly lower in the summer season from the pollution characteristics of water bodies in most areas of the Baiyangdian Lake, and the levels of PAH pollution in the water body of urban residential regions and rural residential regions were relatively higher than those in tourist regions and low human disturbance regions. Source analysis based on diagnostic ratios confirmed that combustion sources and petroleum sources were two main sources for PAHs entering into the waters of the Baiyangdian Lake. Human health risk assessment showed that PAHs in surface waters from the Baiyangdian Lake will not cause a potential non-carcinogenic risk to local residents and the carcinogenic risk could mostly be accepted, but the potential lifetime carcinogenic risk for infants in rural residential regions should be concerned about. Urban residential regions and rural residential regions were subject to higher cumulative non-carcinogenic and carcinogenic risk when compared to the other functional regions. Ecotoxicological risk assessment found a moderate risk to aquatic organisms presented by individual PAH and a low risk by total PAHs, and PAHs in the water body of urban residential regions and rural residential regions also have relatively higher harm effects to aquatic organisms compared with the other two functional regions. This study revealed the pollution characteristics of PAHs and their possible sources in waters of the Baiyangdian Lake, clarified its correlation to regional anthropogenic activities, and provided corresponding risk management strategies for human and aquatic organisms.
Afficher plus [+] Moins [-]Habitat differences affect the nuclear morphology of the erythrocytes and the hepatic melanin in Leptodactylus fuscus (Anura) in the Brazilian Cerrado savanna Texte intégral
2021
Assis, Rhayane Alves | Rezende, Wadson Rodrigues | dos Santos, Cirley Gomes Araújo | Benvindo-Souza, Marcelino | Amorim, Nathan Pereira Lima | Borges, Rinneu Elias | Franco-Belussi, Lilian | De Oliveira, Classius | de Souza Santos, Lia Raquel
The sensitivity of anuran to the effects of habitat destruction and contamination has led to a preoccupying global decline in their populations. Morphological biomarkers such as micronuclei and other erythrocyte nuclear abnormalities (ENAs), as well as the occurrence of hepatic melanin, can be used to evaluate the effects of habitat impacts. In the present study, these two parameters were combined for the in situ assessment of the effects of soybean cultivation on the grassfrog, Leptodactylus fuscus. Specimens were also collected from a protected area to provide a reference site (non-agricultural environment). The frequency of some of the nuclear abnormalities in the animals from the soybean plantation was much higher than that recorded at the reference site, in particular micronuclei, which were 3.6 times more frequent in the plantation, lobulated nuclei (3.4 times more frequent), and reniform nuclei, which were four times more common than at the reference site. The combined analysis of all the ENAs together also revealed a frequency approximately 1.4 times higher in the animals from the soybean plantation, in comparison with the protected area. Smaller areas of hepatic melanin were observed in the specimens from the soybean plantation. These results provide further evidence of the sensitivity of anurans to habitat impacts and indicate that animals found in soybean plantations are susceptible to systematic alterations of their cells.
Afficher plus [+] Moins [-]Optimal allocation of CO2 emission quotas at the city level in Bohai Rim Economic Circle based on multi-objective decision approach Texte intégral
2021
Li, Zhiyuan | Chen, Huadun | Wang, Juan | Zhao, Tao
As the most developed city circle in northern China, allocating CO₂ emission quotas at the Bohai Rim Economic Circle (BREC) city level is essential for developing specific abatement policies. Thus, with reflecting multi-principles (fairness, efficiency, sustainability, and feasibility), this paper formulates the CO₂ emission quota allocation among cities in BREC in 2030 based on the multi-objective decision approach. We first propose three allocation schemes based on the principles of fairness, efficiency, and sustainability, which are conducted by entropy method, zero-sum gains data envelopment (ZSG-DEA) model, and CO₂ sequestration share method, respectively. Then, the CO₂ allocation satisfaction is defined and used to measure the feasibility principle which is integrated as the objective function of the multi-objective decision model together with three allocation schemes to obtain the optimal allocation results. The results show that Beijing, Tianjin, Dalian, Shijiazhuang, Yantai, Weifang, and Linyi enjoy the largest CO₂ emission quotas, having 1179.94 Mt in total and accounting for 31%. Beijing has the highest quotas, and Laiwu has the lowest emission quotas. Cities with large energy consumption and less CO₂ sequestration capacity, such as Tianjin, Handan, and Tangshan, experience a decrease in the emission quota shares from 2017 to 2030, indicating that these cities would undertake large emission reduction obligations. Sensitivity analysis shows that Beijing, Zibo, and Jinan are more sensitive to minimum satisfaction changes, and the total satisfaction experiences an increase first and declines thereafter. Based on the results above, cities with large pressure to reduce CO₂ emissions should not only promote economic development but also improve the capacity of CO₂ sequestration by enhancing environmental protection to realize emission reduction targets.
Afficher plus [+] Moins [-]Development of the Diatom Ecological Quality Index (DEQI) for peri-urban mountain streams in the Basin of Mexico Texte intégral
2021
Salinas Camarillo, Victor Hugo | Carmona Jiménez, Javier | Lobo, Eduardo A.
In the Basin of Mexico, one of the most important economic regions in the country with over 22 million inhabitants, peri-urban streams have been transformed into sewers, drains, and pipes to avoid flooding or unsanitary conditions; the change affects not only the ecosystem’s goods and services but also the aquatic communities that support the natural ecological processes. We aimed to develop a diatom-based diagnosis of the ecological quality of these aquatic ecosystems through the study of epilithic diatom response to regional environmental gradients. Samples of epilithic diatoms and water were collected in 45 sites representing 12 perennial streams, and multivariate analyses were performed on environmental and biological data. The ecological quality gradient to which diatoms responded was related to oxygen saturation, soluble reactive phosphorous, dissolved inorganic nitrogen, and hydromorphological quality. Three species groups were recognized according to their ecological preferences along CCA1 axis, indicators of high and low ecological quality, and tolerant species. By assigning an indicator value to each species group, we calculated the DEQI using the formula adapted from Pantle and Buck, indicating five different ecological quality classes. This index is proposed for complementing the ecological quality evaluation as a biological metric that responds to multiple regional stressors of the structure and function of these peri-urban streams in the Basin of Mexico.
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