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Prefabrication decisions of the construction supply chain under government subsidies Texte intégral
2022
Du, Qiang | Hao, Tingting | Huang, Youdan | Yan, Yunqing
Prefabrication has been generating increasing interest as a cleaner production strategy to promote sustainable development. Alongside this trend, various subsidies have been set to improve prefabrication levels. This paper evaluates the prefabrication levels of buildings through the assembly rate. A series of models are established to investigate the optimal assembly rate under various government subsidies. The optimal assembly rate and subsidy revenue-sharing coefficient are analyzed in both decentralized and centralized scenarios. By comparing the optimal decisions in these two scenarios, a transfer payment contract is proposed that enables the overall coordination of the prefabricated construction supply chain (PCSC). The results show that the optimal assembly rate in the centralized scenario is higher than that in the decentralized one. When the revenue-sharing coefficient is 100%, the subsidy revenue-sharing contract can coordinate the PCSC system and realize the Pareto improvement. When certain conditions are satisfied in the transfer payment contract, business profits can achieve Pareto optimality. This research provides a reference for construction enterprises making decisions to promote the development of PCSC.
Afficher plus [+] Moins [-]ZnCo2O4/g-C3N4/Cu nanocomposite as a new efficient and recyclable heterogeneous photocatalyst with enhanced photocatalytic activity towards the metronidazole degradation under the solar light irradiation Texte intégral
2022
Jahanshahi, Roya | Mohammadi, Alieh | Doosti, Mohammadreza | Sobhani, Sara | Sansano, José Miguel
In this study, ZnCo₂O₄/g-C₃N₄/Cu is synthesized as a new and highly effectual solar light-driven heterogeneous photocatalyst. The prepared photocatalyst is characterized using FT-IR, XRD, XPS, DRS, FESEM, TEM, EDS, and elemental mapping techniques. The performance of ZnCo₂O₄/g-C₃N₄/Cu is studied towards the metronidazole (MNZ) degradation under solar light irradiation. The kinetics of MNZ degradation and efficacy of the operational parameters comprising the initial MNZ amount (10–30 mg L⁻¹), photocatalyst dosage (0.005–0.05 g L⁻¹), pH (3–11), and contact time (5–30 min) on the MNZ degradation process are investigated. Surprisingly, the ZnCo₂O₄/g-C₃N₄/Cu nanocomposite presents a privileged photocatalytic performance towards the MNZ degradation under solar light irradiation. The enhanced photocatalytic activity of this photocatalyst can be ascribed to the synergistic optical effects of ZnCo₂O₄, g-C₃N₄, and Cu. The value of band gap energy for ZnCo₂O₄/g-C₃N₄/Cu is estimated to be 2.3 eV based on the Tauc plot of (αhν)² vs. hν. The radical quenching experiments confirm that the superoxide radicals and holes are the principal active species in the photocatalytic degradation of MNZ, whereas the hydroxyl radicals have no major role in such degradation. The as-prepared photocatalyst is simply isolated and recycled for at least eight runs without noticeable loss of the efficiency. Using the natural sunlight source, applying a very low amount of the photocatalyst, neutrality of the reaction medium, short reaction time, high efficiency of the degradation procedure, utilizing air as the oxidant, low operational costs, and easy to recover and reuse of the photocatalyst are the significant highlights of the present method. It is supposed that the current investigation can be a step forward in the representation of an efficacious photocatalytic system in the treatment of a wide range of contaminated aquatic environments.
Afficher plus [+] Moins [-]On the dynamic return and volatility connectedness of cryptocurrency, crude oil, clean energy, and stock markets: a time-varying analysis Texte intégral
2022
Attarzadeh, Amirreza | Balcılar, Mehmet
The high energy consumption of cryptocurrency transactions has raised concerns about the environment and sustainability among green investors and regulatory authorities. The current study examines the connectedness among clean energy, Bitcoin, the stock market, and crude oil empirically. The time-varying parameter vector autoregression (TVP-VAR) is used to estimate the dynamics of connectedness in a daily dataset spanning the period November 11, 2013 to September 30, 2021. We find that the clean energy and traditional stock markets transmit shocks to Bitcoin and oil in terms of return, and they receive shocks in terms of volatility from Bitcoin and oil. Additionally, Bitcoin and other financial markets are only tenuously linked during non-crisis periods. Nonetheless, their connection strengthens substantially during times of crisis, such as the great cryptocurrency crash of 2018 and the COVID-19 pandemic of 2020. We believe that these findings can help explain how clean energy and cryptocurrency markets are linked during times of crisis.
Afficher plus [+] Moins [-]Bioactivity of Deverra tortuosa essential oil, its nanoemulsion, and phenylpropanoids against the cowpea weevil, a stored grain pest with eco-toxicological evaluations Texte intégral
2022
Almadiy, Abdulrhman A. | Nenaah, Gomah E. | Albogami, Bader Z.
The essential oil (EO) was hydrodistilled from of Deverra tortuosa aerial parts. Fifty-six components amounting 99.3% were identified in EO through using gas chromatography–flame ionization detection (GC–FID) and (GC–MS). Phenylpropanoids, dillapiole (41.6%), elemicin (7.3%) and myristicin (5.1%), and the monoterpene, sabinene (4.2%) were identified as the major terpenes. An oil-in-water nanoemulsion (particle size 70.3 nm) was developed from EO adopting a low-energy method. The EO products showed insecticidal and biochemical effects against the cowpea weevil Callosobruchus maculatus. Based on a 48-h exposure period, the oil nanoemulsion exhibited a superior contact bioactivity (LC₅₀ = 10.3 µg/cm²), followed by EO (LC₅₀ = 23.1 µg/cm²), dillapiole (LC₅₀ = 27.8 µg/cm²), and myristicin (LC₅₀ = 37.1 µg/cm²). Upon fumigation, nanoemulsion and EO were superior as fumigants (LC₅₀ after 48 h were 6.9 and 14.3 µl/l, respectively). Test materials showed a residual bioactivity against C. maculatus, where EO, dillapiole, and myristicin showed the strongest grain protecting activity. EO products significantly inhibited acetylcholinesterase (AChE) activity of C. maculatus adults. Test products were safe toward the non-target earthworms and did not alter the viability of cowpea seeds. There are evidences for the potential of using EO of D. tortuosa and its nanoemulsion and phenylpropanoids as natural grain protectants against C. maculatus.
Afficher plus [+] Moins [-]How green finance and financial development promote green economic growth: deployment of clean energy sources in South Asia Texte intégral
2022
Sadiq, Muhammad | Amayri, Moataz Ahmad | Paramaiah, Ch | Mai, Nguyen Hong | Ngo, Thanh Quang | Phan, Thị Thu Hiền
A major issue for governments in the past few decades has been environmental deterioration caused by economic activity. Researchers are increasingly interested in the factors that contribute to environmental deterioration. This research fills the empirical gaps by looking at the influence of carbon footprints of growth and R&D investment on green finance development of renewable energy. Ordinary least square (OLS) is used in this work to assess the long-term connection between chosen variables in South Asia from 1995 to 2018. The importance of green finance, clean energy, and green financial instability have been identified as major variables. According to the study’s overall findings, clean energy, green finance, and sustainable economic growth are all important and positive indicators of a composite assessment of sustainable practices. Green bonds, reducing greenhouse gas emissions, and green economic development all play an important part in green finance development and renewable energy production. The research also found that R&D expenditures had a positive and substantial influence on green finance development in South Asia, with a 1% increase in R&D expenditures lowering the sustainability of the environment by 0.070% and 0.080%. Other practical consequences for South Asia include a more suitable path toward a greener economy, as suggested by the projected findings.
Afficher plus [+] Moins [-]Histological Biomarkers and Protein Expression in Hyphessobrycon eques Fish Exposed to Atrazine Texte intégral
2022
Brunetti, Isabella Alves | Pereira, Pâmela Castro | Oliveira, Danilo Sagrillos | Silva, Viviane Aline Oliveira | Reis, Rui Manuel | Américo-Pinheiro, Juliana Heloisa Pinê | da Cruz, Claudinei
Pesticides are one of the main sources of pollution on the planet, affecting different environments. The aim of the study was to evaluate the chronic effect of atrazine (ATZ) on brain, gill, and liver histology and the clinical signs of intoxication in Hyphessobrycon eques fish and to determine the effect on the expression of proteins related to proliferation, damage, death, and cellular stress pathways. The chronic toxicity test was performed during 30 days of exposure to ATZ. Concentrations of 0.57, 1.14, 5.74, and 11.50 mg L⁻¹ were applied and there was a control. Aquariums with a capacity of 5 L of water were used with aeration pumps containing 5 animals per replica, weighing between 1.0 ± 0.2 g per organism. At the end of the chronic toxicity tests of ATZ for H. eques, samples of the gills, brain, and liver were collected for histological analysis. The same organs were collected and stored in cryogen tubes in liquid nitrogen until the moment of extraction and then massaged mechanically for the Western-blot technique. In the histopathological analyses, the gills showed the greatest changes in relation to the other organs, such as the loss of support of the secondary lamellae, and the fish also showed a loss of swim bladder capacity. In conclusion, ATZ in the environment, in long-term exposure, can cause histological and biochemical effects, affecting the survival and proliferation of cell pathways.
Afficher plus [+] Moins [-]Mixed effects of perfluoroalkyl and polyfluoroalkyl substances exposure on cognitive function among people over 60 years old from NHANES Texte intégral
2022
Weng, Xueqiong | Liang, Huanzhu | Tan, Yuxuan | Chen, Jingmin | Fei, Qiaoyuan | Liu, Shan | Guo, Xinrong | Wen, Lin | Wu, Yingying | Jing, Chunxia
The relationship between perfluoroalkyl and polyfluoroalkyl substances (PFAS) and cognitive function are inconsistent, and the mixed effects of PFAS on cognitive function are still unclear. We aimed to evaluate the joint effects of PFAS on cognitive function assessed using four tests as follows: the Consortium to Establish a Registry for Alzheimer’s Disease Immediate Recall Test (IRT), Delayed Recall Test (DRT), the Animal Fluency Test (AFT), and the Digit Symbol Substitution Test (DSST) in the US elderly. A total of 777 individuals aged ≥ 60 from the National Health and Nutrition Examination Survey (NHANES) 2011–2014 were included in this study. Multivariable logistic regression and Bayesian kernel machine regression (BKMR) were constructed to estimate the overall and the individual effects of PFAS exposure on cognitive function. There were 21.36%, 22.65%, 21.62%, and 21.24% participants with cognitive decline in IRT, DRT, AFT, and DSST, respectively. After multivariable adjustment, perfluorooctanoic acid (PFOA) was inversely associated with cognitive decline in IRT, DRT, and AFT, while no significant association was observed between any other PFAS and cognitive decline. Compared with the lowest quartile, the adjusted odds ratio of cognitive decline with a 95% confidence interval (CI) for the highest quartile of PFOA was 0.33 (95% CI: 0.15–0.69) in IRT, 0.50 (0.26–0.96) in DRT, and 0.45 (0.21–0.95) in AFT. In BKMR analysis, the overall effect of mixtures was significantly protective on cognitive decline in IRT, of which PFOA made the greatest contribution. The consistent protective effect in DRT and DSST was observed when all the chemicals were at their 50th percentile or below it. No significant interaction was observed among PFAS for cognitive function. These findings suggested that PFAS mixture at a low level of current exposure of the US population may have a protective effect on cognitive function.
Afficher plus [+] Moins [-]Spatial and temporal variability and sources of dissolved trace elements in the Sava River (Slovenia, Croatia) Texte intégral
2022
Lučić, Mavro | Mikac, Nevenka | Vdović, Neda | Bačić, Niko | Nava, Veronica | Vidmar, Janja | Milačič, Radmila
The spatial and temporal variability of dissolved trace elements (Al, As, Ba, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb, Sb, Sr, Ti, U, V and Zn) in the upper and middle reaches of the Sava River during two campaigns (2007/2008 and 2017/2018) was examined. The study also included important tributaries and wastewater effluents. No crucial change in metal concentrations in the Sava River water between the two sampling periods was detected. Elements Co, Cr, Cu, Fe, Sb and Zn had higher concentrations at several sites in the first period, whereas Ba, Cd and Pb in the second period. The influence of wastewater discharges proved to be negligible. The highest levels of potentially toxic metals (Cd, Cr, Cu, Sb, V and Zn) were found downstream of the industrial town of Sisak. Concentration–discharge relationship of dissolved elements showed a chemostatic behaviour for As, Cr, Cu, Sr and V and chemodynamic behaviour for all other elements. The UNMIX model, used to identify and quantify metal sources, indicated that soil weathering was the main source of most elements (Al, As, Ba, Co, Cu, Fe, Li, Ni, Sb, Sr and V), with an anthropogenic contribution for Cd, Mo, Pb, Ti and Zn, while Mn and U were associated with colloid formation. The Sava River was defined as moderately polluted regarding metals, whose water quality meets environmental quality standards (EQS). These results may help to better understand the behaviour of dissolved metals in rivers under anthropogenic pressure and to control pollution in the Sava River Basin.
Afficher plus [+] Moins [-]Toxicokinetic of cyphenothrin in rabbits Texte intégral
2022
Özen, Ferhat | Eraslan, Gökhan
Type II pyrethroids, including cyphenothrin, have a wider efficacy and spectrum of action because they have a killing effect rather than a knockdown effect on pests. For this reason, they are among the most widely used pyrethroid groups today. In addition, this group also has repellent activity. Thus, cyphenothrin is a commonly used pyrethroid, which poses an exposure/toxicity risk for living organisms. Toxicokinetic studies have an important place in predicting the toxicity risks of compounds and evaluating viable treatment options. In this study, the toxicokinetics of cyphenothrin were investigated in rabbits. The animal material of the study comprised 6-month-old female 14 New Zealand rabbits, each weighing 2–2.5 kg. The animals were randomly assigned to two groups, each of 7 animals. The rabbits in group 1 were administered a single dose of 2.5 mg/kg bw cyphenothrin in dimethyl sulfoxide as an intravenous bolus, while the rabbits in group 2 were administered a single dose of 2.5 mg/kg bw cyphenothrin in the same vehicle as an oral bolus. Following the administration of cyphenothrin, blood samples were taken at certain intervals from the auricular vein into heparinized tubes. Plasma cyphenothrin levels were determined by gas chromatography, using a capillary column and a micro-electron capture detector. For orally administered cyphenothrin, the plasma maximum concentration (Cₘₐₓ), time to reach the maximum value (tₘₐₓ), half-life (t₁/₂ᵦ), mean residence time (MRT), area under the curve (AUC₀→∞), and bioavailability (F) values were determined as 172.28 ± 47.30 ng/ml, 1.07 ± 0.42 h, 12.95 ± 1.11 h, 17.79 ± 1.69 h, 2220.07 ± 572.02 ng/h/ml, and 29.50%, respectively. For intravenous cyphenothrin, the t₁/₂ᵦ, MRT and AUC₀→∞ values were ascertained as 7.66 ± 0.74 h, 9.28 ± 0.62 h, and 7524.31 ± 2988.44 ng/h/ml, respectively. Although the bioavailability of cyphenothrin was limited when taken orally, its half-life and mean residence time in the body were found to be long. This suggests that high doses of this pesticide may pose a poisoning risk.
Afficher plus [+] Moins [-]Striving towards sustainable development: how environmental degradation and energy efficiency interact with health expenditures in SAARC countries Texte intégral
2022
Zhong, Ruoyu | Ren, Xuedi | Akbar, Muhammad Waqas | Zia, Zeenat | Sroufe, Robert
The previous studies focused on environmental issues, identifying their root causes, urging prompt action to reduce environmental degradation. In this context, the current article extends the literature by incorporating the ecological impacts on the health sector and the role of sustainable development. The present study adds to the body of knowledge by examining the relationship between CO₂ emissions, sustainable development, energy efficiency, energy intensity, and health expenditures for SAARC countries from 2000 to 2020. Fully modified OLS (FMOLS) and dynamic OLS (DOLS) are used and diagnostic tests to check the association between the variables. The empirical analysis validated the long-run impact of the examined factors on health expenditures. The results show that energy efficiency and sustainable development have a statistically significant negative effect on health expenditures, vice-versa for CO₂ emission. Energy efficiency, energy intensity, and CO₂ emissions have been shown to have a one-way causative relationship with health expenditures, but sustainable development and economic growth have a two-way causation relationship. The better health status of the SAARC economies necessitates the establishment of long-term development strategies, environmental sustainability, and an examination of the energy sector. This work’s conceptual and empirical advances have significant policy ramifications for this part of the globe and its efforts to improve sustainability.
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