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Green synthesis of zinc oxide nanoparticles loaded on activated carbon prepared from walnut peel extract for the removal of Eosin Y and Erythrosine B dyes from aqueous solution: experimental approaches, kinetics models, and thermodynamic studies Full text
2022
Rashtbari, Yousef | Afshin, Shirin | Hamzezadeh, Asghar | Gholizadeh, Abdolmajid | Ansari, Farshid Jaberi | Poureshgh, Yousef | Fazlzadeh, Mehdi
Water contamination due to release of dye containing effluents is one of the environmental problems of serious concern today. The present study investigate the green synthesis of zinc oxide nanoparticles (ZnO-NPs) doped on activated carbon (AC) prepared from walnut peel extract and to estimate its efficiency in the removal of Eosin Y (Eo-Y) and Erythrosine B (Er-B) from its aqueous solution. The synthesized AC-ZnO was identified by field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and the Brunauer–Emmett–Teller. The influence of various parameters such as pH, dosage of AC-ZnO, contact time, and concentrations of Eo-Y and Er-B was also studied. The pH 3 was observed as the optimum pH while the equilibrium was noticed to reach in 30 min at dosage of 1 g/L and initial concentration 100 mg/L for Eo-Y and Er-B adsorption onto AC-ZnO. The maximum adsorption capacity of Eo-Y and Er-B onto AC-ZnO was found to be 163.9 and 144.92 mg/g (and removal efficiencies of 95.11 and 98.31 %), respectively. The process of Eo-Y and Er-B adsorption on AC-ZnO was observed to be depended on the pseudo-second-order kinetic model which indicates chemisorption processes. Langmuir adsorption isotherm model test described the removal of Eo-Y and Er-B on AC-ZnO. The thermodynamic data indicated that the adsorption was endothermic process. Also, the values, SBET and VTOTAL, for the AC-ZnO were equal to 725.65 m²/g and 0.6004 cm³/g, respectively. The results of this study exhibited that AC-ZnO was a very effective method that can be used for the removal of Eo-Y and Er-B from aqueous solutions.
Show more [+] Less [-]Promotional effect of ZrO2 and WO3 on bimetallic Pt-Pd diesel oxidation catalyst Full text
2022
Fan, Rongrong | Li, Zhaoqiang | Wang, Yu | Wang, Yan | Ding, Zhan | Zhang, Cheng | Kang, Na | Guo, Xin | Wang, Rong
Diesel oxidation catalysts Pt-Pd-(y)ZrO₂-(z)WO₃/CeZrOₓ-Al₂O₃ with total Pt & Pd loading of only 0.68 wt.% were prepared and investigated for oxidation activity and stability of CO, C₃H₆, and NO. Introduction of ZrO₂ greatly improved low-temperature activities and retained stability especially for CO and C₃H₆ oxidation after treated at 800 °C. With the optimal loading amount of 6 wt% ZrO₂, 2 wt% WO₃ was introduced to the system and showed higher activity. Reaction temperature for 50% CO and C₃H₆ conversion declined to 160 and 181 °C, and the maximal NO conversion increased to 50%. By using XRD, TEM, CO chemisorption, XPS, and H₂-TPR analysis, it was found that ZrO₂ could inhibit aggregation of Pt and Pd, improve metal dispersion, and increase surface-chemisorbed oxygen after high-temperature treatment, accounting for promoted performance. Also, there were more reducible oxide species in ZrO₂-doped catalysts. ZrO₂ could induce reduction of noble metal oxides and surface ceria by weakening Pt-O-Ce interaction, which increased the ability to dissociate H₂ and spillover effect of dissociated hydrogen to ceria. Doping WO₃ increased metal dispersion of fresh samples and brought more Pt⁰ species that were active sites for oxidation reactions. Thus, ZrO₂ and WO₃ could be effective additives for oxidation catalysts to synergistically improve their activities and thermal stability.
Show more [+] Less [-]Transboundary watershed pollution control and product market competition with ecological compensation and emission tax: a dynamic analysis Full text
2022
Yi, Yongxi | Ding, Caini | Fu, Chunyan | Li, Yuqiong
Product competition and pollution control are closely related to watershed environmental management, but existing literature rarely investigates them in an identical framework. Therefore, this paper develops a multiple differential game model to analyze product market competition and ecological compensation games between watershed regions based on the assumption that a region can choose four strategies to regulate its manufacturers while cooperating with other regions in the basin. Then, we solve the model and obtain a simultaneous equilibrium between the governments and manufacturers for the first time. The results show that the combination of emissions tax and ecological compensation results in the highest social welfare and water ecology for all regions in a basin. Furthermore, the ecological compensation rate independent of emissions tax policy and ecological compensation does not shift investment from downstream to upstream, but it can induce the upstream region to increase investment in management. In addition, if the governments impose an emissions tax, manufacturers’ output in both regions decreases, and the upstream region is higher than in the downstream region.
Show more [+] Less [-]The relationship between energy consumption, natural resources, and carbon dioxide emission volatility: empirics from G-20 economies Full text
2022
Yu-Ke, Chen | Awan, Rehmat Ullah | Aziz, Babar | Ahmad, Ishtiaq | Waseem, Sarah
The present study investigates the causality between energy consumption, natural resources, and carbon emissions volatility. For empirical results, the study analyzed panel data of a Group of Twenty (G-20) countries from 1995 to 2018. The results of Pooled Mean Group (PMG) showed that the consumption of conventional energy sources increases the carbon emissions in the region under consideration. The results also showed that economic growth and carbon emissions are associated with each other according to the Environmental Kuznets Curve hypothesis. The findings showed that rent on mineral resources, oil resources, and forest rent have a positive and significant impact on carbon emissions in G-20 countries. The findings of this study show the complex nature of the relationship between natural resources consumption and carbon dioxide emissions. The study suggests a three-dimensional policy framework for the group of twenty countries of economic cooperation to address the environmental issues with a special focus on natural resources preservation and green economic growth.
Show more [+] Less [-]Remediation of diesel-contaminated soil by alkoxyethanol aqueous two-phase system Full text
2022
Shang, Zhijie | Xu, Pan | Yue, Haoyu | Feng, Dongyue | Zhu, Taohua | Li, Xinxue
The increasing diesel pollution accidents pose a serious threat to the ecological environment and human health. Remediation of diesel-contaminated soil (DCS) has attracted widespread attention during the past few decades. This work proposed an approach for the remediation of DCS by alkoxyethanol aqueous two-phase extraction (ATPE), which was an application of this small molecule aqueous two-phase system (ATPS). In addition, the influence of temperature, stirring speed, stirring time, and solid–liquid ratio on the removal of diesel was explored respectively. The removal efficiency of diesel could reach more than 97.18% in 18 min. Meanwhile, ATPS had high reusability, and the removal efficiency remained above 85.17% in the reuse process. Alkoxyethanol ATPE could effectively remove diesel hydrocarbons with different carbon chain lengths and the remediation process hardly caused residual organic solvents on the soil surface according to the analysis of gas chromatography-mass spectrometry (GC–MS) and Fourier transforms infrared (FT-IR), which could be regarded as the distinct advantage compared to the traditional surfactant washing method and organic solvent extraction method. The study of soil physicochemical properties and wheat germination proved that the soil structure and properties changed little after ATPE remediation. And finally, the mechanism of alkoxyethanol ATPE was intensively discussed according to the remediation characteristic. This work provided an efficient method for the remediation of DCS and widened the application fields of alkoxyethanol ATPS as well.
Show more [+] Less [-]Nexus between indigenous ecological knowledge and ecosystem services: a socio-ecological analysis for sustainable ecosystem management Full text
2022
Das, Manob | Das, Arijit | Seikh, Selim | Pandey, Rajiv
The well-being of the human society cannot be ensured and sustainable unless the flow of Ecosystem Services (ESs) would be matching with their consistent demand. The consistent flow of ESs required sustainable management of ecological resources of the ecosystem. The management of ecosystem can be ensured with variety of approaches. Integration of indigenous ecological knowledge (IEK) in management prescription with the view that IEK-based extraction of ESs ensures removal of resources from the ecosystem within the limit thereby ensuring the sustainability of ecosystem. The present study is an evaluation to understand the nexus between ESs and IEK for sustainable environmental management. The focus of the study was a tribal dominated socio-ecological patch of Barind Region of Malda district, Eastern India. The assessment of ESs and IEK was based on the data collected from the randomly selected tribal households following the pre-tested questionnaire containing questions on ESs as per millennium ecosystem assessment. The data were analyzed following social preference approach, and statistical tests (Kruskal-Wallis and Mann-Whitney). General linear model (GLM) has also been used to examine the impact of socio-demographic attributes on the perceived valuation of ESs. The results revealed that the provisioning ESs (such as water, fuel wood, medical plants) were most preferred followed by cultural and regulating ESs by tribal. Differential importance of ESs was observed among tribal and accounted by gender, education as well as age of the tribe. A gap between the actual accessibility and evaluation of ESs by the tribal communities was also apparent. The socio-demographic attributes have an immense impact on the valuation of ESs and also governed based on the IEK. Various types of indigenous ecological belief systems were closely linked with conservation of ecosystem and sustainable supply of ESs. The present study can contribute to understand socio-ecological nexus with the lens of IEK in tribal dominated ecological landscapes for improved ecosystem and environmental management besides ensuring sustainability of flow of ESs.
Show more [+] Less [-]Air pollution increased risk of reproductive system diseases: a 5-year outcome analysis of different pollutants in different seasons, ages, and genders Full text
2022
Li, Ya | Du, Juan | Lin, Shanshan | He, Huihui | Jia, Rui | Liu, Weihong
Air pollution remains a serious environmental problem worldwide, and the effects of air pollutants with reproductive system diseases have already attracted extensive attention. The present study investigated the risk of air pollutants on reproductive system diseases, based on daily medical visits (DMV) of the past 5 years in central China. Data of DMV outpatients with reproductive system diseases were obtained from a general hospital in Zhengzhou, October 28, 2013 to May 31, 2018, as well as atmospheric pollutants data. Correlation of air pollutants and DMV was analyzed with distributed lag nonlinear model (DLNM), including total cases of reproductive system diseases, and in different seasons (spring, summer, autumn, and winter), genders (male and female), and age groups (<26, 26–35, and >35 years old). A total of 374,558 visits were included. NO2 was most closely relevant to incidence risk of total cases analysis with each increased interquartile ranges (IQRs) in the 6 pollutants, with 30-day lag. Relationship to pollutants was more sensitive in fall, >35 years old, and male groups than in other seasons, ages, and females, and NO2 had the highest risk on reproductive diseases. Air pollution increased risk of reproductive system diseases, and different pollutants played different roles in different seasons, ages, and genders. The results of this study will provide evidence for effective air quality controlling and human reproductive protection.
Show more [+] Less [-]The impact of COVID-19 on the sustainability of the environment, animal health and food security, and safety [Erratum: October 2022, v.29(47); p.70832] Full text
2022
Alshubaith, Ibrahim H. | Alhajri, Salah | Alhajri, Ahlam | Alsultan, Raed A. | Azhar, Esam I. | Alhussaini, Bakr Hussain | Al Solami, Lafi S. | de Oliveira, Maria Cristina | Khafaga, Asmaa F. | Alqurashi, Adel D. | Attia, Youssef A.
COVID-19 pandemic influenced the environment, animal health, and food security. Due to reduced human mobility, the air and water quality increased. Other environmental consequences were the personal protective types of equipment and their haphazard disposal. Atmospheric pollution could be a cofactor leading to an increased COVID-19 mortality rate. Lockdown, however, caused a reduction in air and water pollution. Noise pollution affects the health of individuals and communities in terms of cardiovascular disorders and sleeping problems. Meanwhile, the COVID-19 lockdown controls human activities that reduce noise pollution. Municipal waste affects the environment. Recycling has been reduced in some countries but not in Saudi Arabia. COVID-19 had a drastic effect on livestock production on national, regional, and global levels, affecting countries’ capacities to prevent and control diseases of animals and increasing global poverty, becoming a threat to the sustainability of global food security and safety. Many lessons have been learned from the COVID-19 pandemic, so it is wise to study and analyze the previous lessons and shed some light on past pandemics such as the Spanish flu to understand the readings and earn experiences. This paper is focused on the interaction between the pandemic and environmental health from the public health concern rather than other health classifications.
Show more [+] Less [-]Reflection on the joint prevention and control of air pollution from the perspective of environmental justice—insights from a two-stage dynamic game model Full text
2022
Du, Juan | Sun, Liwen
The practices of the joint prevention and control of air pollution (JPCAP) present two disadvantages: the low enthusiasm of governance subjects and an unsatisfactory governance effect. Revealing the existing problems and exploring their causes has been a key issue for promoting JPCAP. Given this, we especially establish a two-stage dynamic game model for air pollution control to explore the advantages and dilemmas of JPCAP by analyzing changes in environmental tax rate and social welfare. The results show that the unfair distribution of social welfare among cities is a key reason for the unsatisfactory effect of JPCAP. Therefore, we improve JPCAP by considering both production-oriented and consumption-oriented pollutions based on environmental justice. In the improved JPCAP mode, the social welfare of each city is higher than that of non-joint control of air pollution (NJCAP), in which the increased degree is positively related to the city’s negotiation ability. In addition, the consumption tax rate is negatively correlated with the negotiation ability of the central city and the trade transfer coefficient. This study not only provides a theoretical and methodological reference for formulating effective planning and compensation scheme for JPCAP but also can be extended to the practice and theoretical analysis of other cross-regional public issues.
Show more [+] Less [-]China’s Jinshan Yinshan sustainability evolutionary game equilibrium research under government and enterprises resource constraint dilemma Full text
2022
Li, Cai | Firdousi, Saba Fazal | Afzal, Ayesha
This paper is based on analyzing the process of green innovation inspiration and green innovation compensation effect after the implementation of environmental regulations by the Chinese Government. This paper tests the hypothesis using the evolutionary game model and studies the underlying behavioral characteristics of the government, enterprises, and the relevant influencing factors. These influencing factors further aid in examining the evolution law applicable on both sides, which are aligned with the dynamic replication equation and evolutionary equilibrium states under different situations. The key variables used in this study include the concentration of government’s environmental regulation, the cost of the regulations, economic penalties, enterprise’s green innovation-related income, expenditures, and the enterprise’s performance appraisal. Moreover, the results of this study reflect the system stability and equilibrium strategy on the proportion of retained earnings spent by enterprises on green innovation activities and the Government’s strict environmental regulations. In the process of game strategy selection between the government and enterprises, the net income and weight of eco-efficiency indicators of the enterprises actively carrying out green innovation activities play a decisive role. Moreover, there should be reduced weight of economic benefits and increase the economic sanctions and innovation subsidies of enterprise pollution behaviors. Furthermore, reduced cost of regulations and innovation expenditures help guide enterprises to rationally allocate superior resources to enhance green enterprise innovation and take the level of innovation to the point that it achieves a win-win green sustainable development of economic performance and environmental performance.
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