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Framework and implementation of a fuzzy logic filter—an optimization strategy for the BWMS based on stakeholders’ perspectives Полный текст
2020
da Silva Jorge, Sara | Satir, Tanzer
The International Convention for the Control and Management of Ships’ Ballast Water and Sediments (IMO 2018 Edition) was adopted in 2004 and came into force on 8 September 2017, aiming to introduce global regulations to control the transfer of potentially invasive species. Large efforts have been made by the maritime industry in creating reliable strategies for the installation of systems on board (Register 2014). Environmental considerations (INTERTANKO 2018) and optimization for the management systems (IMO 2017 Report) are factors broadly considered to tackle this matter. A consistent implementation strategy must be stated before the ballast water management system (BWMS) installation project starts—the management of stakeholders (e.g. ship owners, classification societies, administration, shipyards) is an important aspect of this process. This relies on their expertise, which in turn results in a high level of engagement and supports the implementation plan into the organizations. The creation of a framework for the optimization process, considering the implementation project of a BWMS on board of oil tankers, is the first part of this research. The use of fuzzy logic principles in the second part—as an evaluation instrument from a ranking obtained by multicriteria principles—sums up the aim of this paper, where the peculiarities about oil tankers’ modelling will be discussed throughout the analysis of 2 optimization cases (Suezmax and Aframax).
Показать больше [+] Меньше [-]Facile synthesis of a novel Ag3PO4/MIL-100(Fe) Z-scheme photocatalyst for enhancing tetracycline degradation under visible light Полный текст
2020
Xu, Jun | Xu, Jinmei | Jiang, Qishao | Cao, Yu | Xu, Kailin | Zhang, Qiuya | Wang, Liping
In this work, a novel visible light–driven heterostructure Ag₃PO₄/MIL-100(Fe) composite photocatalyst was successfully synthesized via facile chemical deposition method at room temperature. Especially when the mass ratio of Ag₃PO₄ was 20% of MIL-100(Fe) (APM-2), it displayed the best photocatalytic performance, for which the degradation rate of tetracycline (TC) in conventional environment was 6.8 times higher than that of bare MIL-100(Fe). In addition, the effects of the initial concentration and pH of the solution on the degradation of tetracycline were also studied, and the results showed that the degradation of tetracycline was more favorable in a weakly alkaline environment. The excellent performance of Ag₃PO₄/MIL-100(Fe) composites was attributed to the fact that on the basis of having adequate photocatalytic active sites, modifying MIL-100(Fe) with an appropriate amount of Ag₃PO₄ particles can more effectively separate photogenerated electron–hole pairs. Five cycles of experiments showed that APM-2 has good photostability. Lastly, it was proved through quenching experiments that •O₂⁻, h⁺, and •OH all played corresponding roles in the degradation process, and a possible Z-scheme heterostructure photocatalytic degradation mechanism was proposed.
Показать больше [+] Меньше [-]Dynamics of soil organic carbon in Typic Torripsamment soils irrigated with raw effluent sewage water Полный текст
2020
Elcossy, Salah A. E. | Abbas, Mohamed H. H. | Farid, Ihab M. | Beheiry, Gamal Gh. S. | Abou Yuossef, Mohamed F. | Abbas, Hassan H. | Abdelhafez, Ahmed A. | Mohamed, Ibrahim
The current research aimed at collecting detailed information about the consequences of cropping history on the accumulation of soil organic carbon (SOC) within different soil depths, i.e., 0–10, 10–20, 20–30 and 30–60 cm. The study site is located at El Gabal El Asfar area (Egypt) whose soils were irrigated with raw sewage effluent as a sole source of irrigation for different periods extended up to 80 years. SOC increased progressively with increasing cropping time, and on the other hand, decreased noticeably with increasing soil depth. The increases significantly correlated with both of the silt and clay contents in soils which increased with time. Soil bulk density and the hydraulic conductivity significantly and negatively correlated with SOC, respectively. Fractions of SOC, i.e., water soluble C, hot water C and soil biomass C in the surface soil layer (0–10 cm), increased progressively with increasing time of land use. Such pools significantly correlated with SOC on one hand and with each other on the other hand. Active (labile) organic carbon fraction increased with time. This fraction also significantly correlated with the different C pools. In conclusion, the hypothesis that SOC is physically protected against soil microbes within the soil requires more investigations to clarify such results obtained herein because this study highlighted the presence of a dynamic equilibrium among the different fractions or pools of the SOC.
Показать больше [+] Меньше [-]Association of tobacco smoke–infused water (tuibur) use by Mizo people and risk of Helicobacter pylori infection Полный текст
2020
Mukherjee, Subhajit | Madathil, Sreenath Arekurnnath | Ghatak, Souvik | Jahau, Lalrintluanga | Pautu, Jeremy L. | Zohmingthanga, John | Pachuau, Lalawmpuii | Nicolau, Belinda | Kumar, Nachimuthu Senthil
The study aims to understand the influence of environmental and lifestyle factors and more specifically the role of tobacco smoke–infused water (tuibur) on Helicobacter pylori infection. It was a cross-sectional study to measure the epidemiological risk factors associated with H. pylori infection among the tribal population in Northeast India. Endoscopic samples were collected from the antrum region of the stomach from 863 participants with gastritis. H. pylori infection was confirmed in 475 samples by the rapid urease test and PCR-based methods. Information on demographic and lifestyle factors was collected using a validated and standardized questionnaire. Logistic regression was used to estimate odds ratio (OR) and 95% confidence interval (CI) for the association between the various factors and H. pylori. The use of tuibur was associated with an increased OR of H. pylori infection (OR = 3.32, 95% Cl = 1.95–5.83). Tobacco chewers (OR = 1.49, 95% Cl = 1.06–2.09), smokers (OR = 1.81, 95% Cl = 1.26–2.61), and alcohol consumers (OR = 1.81, 95% Cl = 1.19–2.76) were also infected with H. pylori. The results were not attenuated after adjusting for major well-known risk factors of H. pylori infection. The habit of tuibur consumption may be a contributing factor to the high prevalence of H. pylori infection and in turn, may contribute to the high prevalence of gastritis among the Mizo population.
Показать больше [+] Меньше [-]Analysis of the PM2.5 emission inventory and source apportionment in Jilin City, Northeast of China Полный текст
2020
Fang, Chunsheng | Wang, Liyuan | Gao, Hanbo | Wang, Ju
This study collected and compiled statistical data on atmospheric pollution in Jilin City, China during 2013–2014, using models and methods to calculate the source proportion of PM₂.₅ emitted by various sources. The statistical activity levels and emission factors of various pollution sources were found to be key parameters for obtaining the total amount of PM₂.₅ in the exhaust gas emitted from all types of pollution sources using an emissions model. In this study, relevant data were collected by the top-down method, and pollutant emission was calculated by the emission factor method to establish the PM₂.₅ pollution emission inventory of Jilin City. The source apportionment was calculated using the Chemical Mass Balance (CMB) model. Industrial process source and fixed combustion source are the largest sources of PM₂.₅ emission from all sources, respectively. Among the two calculation results, the results of pollution emission inventory are more accurate. The PM₂.₅ emission inventory in Jilin was established and countermeasures were proposed focused on the coordinated control of air pollution and the prevention and control of industrial dust pollution sources, as well as environmental management and impact assessment.
Показать больше [+] Меньше [-]Electrical energy efficiency of China and its influencing factors Полный текст
2020
Guang, Fengtao
Due to the implementation of “electrical energy substitution” strategy in China, the proportion of electrical energy in terminal energy consumption is increasing. The improvement of electrical energy efficiency could increase overall energy efficiency. Thus, a special attention should be paid on electrical energy efficiency. An input-oriented epsilon-based measure-DEA (data envelopment analysis) model was used to measure electrical energy efficiency from the perspective of total factor, and the spatial-temporal variability of electrical energy efficiency was investigated. Results draw that the overall electrical energy efficiency is relatively low and shows a downward trend. The eastern region has the best scores of electrical energy efficiency, followed by the central region and then the western region. Furthermore, the main associated determinants were investigated by panel Tobit regression model. It was found that the effect of industrial structure and economic opening degree on electrical energy efficiency is positive on the whole country level, whereas the effect of government intervention and urbanization is negative. From a regional perspective, there are great differences in the effect of each influencing factors. Some corresponding policy recommendations are given.
Показать больше [+] Меньше [-]The role of ICT in energy consumption and environment: an empirical investigation of Asian economies with cluster analysis Полный текст
2020
Arshad, Zeeshan | Robaina, Margarita | Botelho, Anabela
The development of societies has led information and communication technology (ICT) to play a gradually important role in people’s lives, transforming the way societies and economies function. ICTs are often associated with the path to reducing CO₂ emissions; however, do they lead to that path? Or are they themselves a growing source of energy consumption and emissions? The current study estimates the effect of ICT, trade, economic growth, financial development, and energy consumption on carbon emissions in South and Southeast Asian (SSEA) region for the period of 1990–2014. Moreover, the study also tried to validate the environmental Kuznets curve (EKC) hypothesis between GDP per capita and CO₂ emissions. Cluster analysis was used to identify two groups (potential and advanced countries) based on their social development score. The long-run connection between the variables was examined and the long-run elasticities of ICT, financial development, energy consumption, trade, and economic growth with respect to CO₂ emissions were estimated. Besides, individual country-wise long-run coefficients were found. Results show that financial development and ICT deteriorated the environment quality in the SSEA region, suggesting ICT goods and services are not energy-efficient in both potential and advanced countries and that most of the financial investment was made in non-friendly environmental projects, in potential countries. On the contrary, in advanced countries, financial development mitigates CO₂ emissions. In addition, results also confirmed an inverted U-shaped relationship for all the considered three panels such as potential, advance, and full-countries panels, confirming EKC. Causality findings showed a bidirectional causality between CO₂ emissions and energy consumption as well as unidirectional causality from trade, economic growth, financial development, and ICT to CO₂ emissions. Policymakers should be aware of the ICT impact on energy consumption and strengthen the regulation of their manufacture to facilitate the integration of energy efficiency into user routines. Due to the increasing use of standby mode and Wi-Fi assistive devices, the rapid implementation of legislation regulating these technologies to make them more efficient is recommended.
Показать больше [+] Меньше [-]Correction to: High efficiency inactivation of microalgae in ballast water by a new proposed dual-wave UV-photocatalysis system (UVA/UVC-TiO2) Полный текст
2020
Lu, Zheng | Zhang, Kun | Liu, Xiaolei | Shi, Yue
In the third paragraph of Introduction, the sentence “Few scholars have conducted static studies on dual-wavelength UV photocatalytic technologies (Ma 2018)”.
Показать больше [+] Меньше [-]The potential persistence of abundant submerged macrophyte and phytoplankton in a shallow system at very high nutrients loading: results from a mesocosm study Полный текст
2020
Zhu, Mingming | Zhang, Xiufeng
Shallow lakes are typically either in a clear water state with high abundance of submerged macrophytes or in a turbid state dominated by phytoplankton. A 10-week mesocosm experiment was set up to test the hypothesis that in a very shallow aquatic ecosystem impacted by very high nutrient loading, both submerged macrophytes and phytoplankton may be abundant. Nutrient levels, phytoplankton biomass (measured as chlorophyll a, Chl a), total suspended solids (TSS), inorganic suspended solids (ISS), and submerged macrophyte biomass were measured in three different treatments: DH (deep (1 m) water with very high nutrient loading), SH (very shallow (0.5 m) water with very high nutrient loading), and SL (very shallow (0.5 m) water with low nutrient loading). Of the three treatments, the DH mesocosms exhibited the highest nutrient, the TSS and ISS levels, the highest phytoplankton biomass, and the lowest submerged macrophyte biomass, while the lowest nutrient, the TSS and ISS levels, the lowest phytoplankton biomass, and the highest submerged macrophyte biomass were observed in the SL treatment. All measured parameters exhibited intermediate levels in the SH treatment. Our study demonstrates that in very shallow aquatic ecosystems with very high nutrient loading, submerged macrophytes and phytoplankton may persist in an intermediate but potentially unstable state with medium water clarity. These findings may contribute to the understanding of the mechanisms involved in regime shifts in shallow lakes.
Показать больше [+] Меньше [-]Copper-induced oxidative stress and biomarkers in the postlarvae of Penaeus indicus Полный текст
2020
Thatipaka, Samuel David Raj | Paila, Rupa Vani | Polaki, Suman
The objective of the present research is to study the levels of reactive oxygen species (ROS) and protein carbonyl (PC) and the functional protein levels of metallothioneins (MT) in Penaeus indicus postlarvae (PL) upon sublethal copper exposure and to determine the biomarkers. The PL were exposed to sublethal copper of 0.164 ppm. The experiments were carried out in the laboratory over a period of 30 days with sampling intervals of 24, 48, and 96 h and 10, 20, and 30 days. The present study confirms that high oxidative stress can be induced from 24 h onwards upon sublethal exposure to copper in P. indicus PL. This is evident from the increasing levels of ROS in the exposed PL during both short-term and long-term exposures to sublethal copper. Since variability in metallothionein levels from 24 h through 30 days of experimental period was observed, metallothioneins cannot be regarded as a good biomarker as far as copper toxicity with respect to P. indicus PL is concerned. The effect of copper on protein carbonyl seems to be very rapid and consistent. The results suggest that protein carbonyl in P. indicus PL is significantly induced in a time-dependent manner upon copper exposure even at sublethal dose, and it seems reasonable to support that protein carbonyl could be used as a biomarker to copper toxicity.
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