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The impact of output volatility on CO2 emissions in Turkey: testing EKC hypothesis with Fourier stationarity test 全文
2022
Genç, Murat Can | Ekinci, Aykut | Sakarya, Burçhan
This study uses the output volatility–augmented environmental Kuznets curve (EKC) model to determine the dynamic short- and long-term impacts of the volatility of economic growth (VOL) on carbon dioxide (CO₂) emissions in Turkey from 1980 to 2015. The results of the autoregressive distributed lag (ARDL) approach indicate that there is a long-run relationship between CO₂, per capita real GDP, per capita energy use, and VOL. The coefficients obtained from the ARDL estimation indicate that economic growth and energy use increase CO₂ emissions, while VOL decreases CO₂ emissions in the long run. Moreover, the coefficients obtained from the ARDL error correction model show that VOL decreases CO₂ emissions in the short run, as well. We also find that the EKC is valid in Turkey. This implies for the Turkish case that achieving macro-stability under a “just transition” is key for achieving both economic and environmental benefits from ratifying international agreements such as Paris Agreement and EU Green Deal.
显示更多 [+] 显示较少 [-]How will Chinese cities reduce their carbon emissions? Evidence from spatial differences 全文
2022
Yan, Junna | Zhang, Zhonghua | Chen, Mingli | Lin, Tao | Yuan, Ke
Urban regions are the dominant carbon emitter in China. Although the role of urban regions is a crucial concern in peaking China’s carbon emission in 2030 or earlier, there were little focus set to the driving factors among urban regions from spatial differences. To excavate more effective abatement strategies to China’s cities, this paper improved the environmental Leontief and Ghosh input–output models and structural decomposition analysis to investigate the driving factors of the spatial differences in the CO₂ emissions among four municipalities. The results released that the increasing enlarged spatial differences of CO₂ emission were significant. In general, the spatial differences were dramatically influenced by the per capita final demand level from the demand perspective and the sectoral energy intensity from the supply perspective. In particular, the structural factors presented an increasingly critical role. Inspired by the results, the city level “common but distinct” policy implications were formulated.
显示更多 [+] 显示较少 [-]Environmental courts and foreign direct investments: evidence from China 全文
2022
Huang, Xiaoqi | Liu, Wei | Cao, Zhi
As China’s pollution problems worsen, environmental disputes are increasing rapidly. However, only 1% of environmental disputes can be resolved via judicial channels. Based on the establishment of environmental courts since 2007, we employ the multi-period DID approach to investigate the impact of environmental courts on foreign direct investments. We find that (1) compared with cities without environmental courts, FDI of cities with environmental courts would drop by 3.32% from the average, which is consistent with the pollution haven hypothesis. Besides, we verify the credibility of the conclusion through detailed endogeneity discussions, placebo tests, and robustness tests. (2) The negative effect of environmental courts on foreign direct investments is more salient in the east, regions with higher historical environmental investment, and regions with more serious local protectionism. (3) There are two channels. The greater risks of environmental litigation and stricter environmental public supervision brought by environmental courts would lead to additional environmental violation costs, thereby inhibiting foreign direct investments. Our findings provide new causal evidence for the pollution haven hypothesis from the perspective of intensive environmental justice.
显示更多 [+] 显示较少 [-]Diazinon pesticide photocatalytic degradation in aqueous matrices based on reductive agent release in iodide exciting under UV Irradiation 全文
2022
Azarpira, Hossein | Rasolevandi, Tayebeh | Mahvi, Amir Hossein | Karimy, Mahmood
Regarding the cost-effective degradation of diazinon (DIZ), the present study was conducted to develop and UV/iodide process in a photo catalyst reactor. CCD modeling applied and the results shows that the highest R-squared value (adjusted R-squared: 0.9987), the lowest P-value (2.842 e − 10), the lowest AIC (14.54), and the most insignificant lack-of-fit (0.73) belonged to the second-order model. Based on second-order model, the stationary points for time, iodide: DIZ (molar ratio %), DIZ concentration, and pH were 6.99 min, 80.15% iodide: DIZ (molar ratio %), 3.34, mg L⁻¹, and pH 7.34 (− log₁₀[H⁺]), respectively. The maximum reduction efficiency of 97.22% was obtained at the experimental conditions. The LC–MS analyses from optimal condition implied that all the DIZ molecules and its intermediates breaking to simple compounds during 15 min of processing. The data shown UI process reduced the BOD and COD levels by about 66% and 86.29% within 80 min of photoreaction, respectively. Furthermore, in kinetic investigation, with the increase in DIZ concentration, kₒbₛ and rₒbₛ increased and secondly, the conventional and PCBR reactor kₒbₛ increased by about respectively 17% and 50% with an increase in DIZ concentration from 5 to 15 mgL⁻¹. Additionally, when the DIZ concentration increase from 5 to 15 mg L⁻¹, rₒbₛ increased in the conventional and PCBR reactors respectively about 4.9 and 6 times. Figure-of-merit EEₒ changed from 12.66–17.41 to 7.26–10.15 kWhm³ for the conventional reactor, and 8.66–13.61 to 5.24–8.12 kWhm³ in PCBR, when the DIZ concentration increasing from 5 to 15 mg L⁻¹. Consequently, in the PCBR reactor, the energy consumption reduced by 14% at 5 mg L⁻¹ DIZ concentration and by 60% at 15 mg L⁻¹ DIZ concentration. Also, total cost of the system (TCS) decreases from 4.52 to 1.46 $ in conventional reactor and 1.47 to 0.42 $ in PCBR reactor when the DIZ concentration increase from 5 to 15 mg L⁻¹.
显示更多 [+] 显示较少 [-]Effective removal of Sb(V) from aqueous solutions by electrocoagulation with composite scrap iron-manganese as an anode 全文
2022
Zhou, Yongchao | Zheng, Wenxin | Zhang, Wenming | Zhang, Yiping | Fang, Lei
Improving the removal rate of pentavalent antimony (Sb(V)) by electrocoagulation (EC) is of great significance to the environment. In this paper, the EC with composite scrap iron and manganese filings as an anode (Fe–Mn EC) was investigated for the high-efficiency elimination of Sb(V). The results showed that Fe–Mn EC can enhance the removal of Sb(V) by 11.18–17.36% compared with the traditional iron electrocoagulation (Fe EC). Meanwhile, Sb(V) removal increased with the growth of current concentration as well as Mn content in the anode. However, the Sb(V) removal rate was inhibited when Mn content exceeded 20%. Moreover, the flocs generated during the Fe and Fe–Mn EC (Fe flocs and Fe–Mn flocs) were analyzed both structurally and theoretically using XRD, SEM, BET, and adsorption experiment. The results indicated that the components of Fe–Mn flocs were mostly Mn-substituted FeOOH, which appeared as the structure of nanometer flakes and large internal surface areas. Meanwhile, the Fe–Mn flocs had the ability of much faster Sb(V) adsorption rate; its Sb(V) adsorption capacity was 2.5 times more than that of the Fe flocs. The thermodynamics constants of both Fe and Fe–Mn flocs proved that adsorption was associated with monolayer physical adsorption. To the best of our knowledge, this is the first report of the electrocoagulation with composite scrap iron-manganese as an anode to remove Sb, which provide a new idea and potential technical support for the removal of Sb(V).
显示更多 [+] 显示较少 [-]Physalis pubescens L. alleviates testicular disruptions associated with streptozotocin-induced diabetes in male Wistar rats, Rattus norvegicus 全文
2022
Ali, Atef Abdel-Moneem | Essawy, Ehab Abdel-Raouf | Mohamed, Noha Sayed | Abdel Moneim, Ahmed E. | Attaby, Fawzy Ali
Testicular impairment is a serious complication of diabetes that is mediated by oxidative stress and inflammation. Physalis has antioxidative and anti-inflammatory actions. Thus, the present study investigated the ameliorative role of Physalis juice (PJ) prepared from the fruits against testicular damages in streptozotocin (STZ)-induced diabetic rats. Adult male Wistar rats were divided randomly into five groups (n=6): control, orally administered 5 mL PJ/kg daily (PJ), injected intraperitoneally with a single dose of 55 mg STZ/kg without treatment (STZ), or treated daily with PJ (STZ+PJ) or with 500 mg metformin/kg (STZ+Met), for 28 days. The STZ group showed a marked elevation in the blood glucose level by 230%, whereas remarkable declines in the serum levels of testosterone (44%), follicle-stimulating hormone (FSH) (48%), and luteinizing hormone (LH) (36%), as compared to controls. In comparison to controls, the testis of the STZ group showed remarkable declines in the testis weight (15%), the glutathione (GSH) content (45%), mRNA and protein levels of B-cell lymphoma-2 (Bcl-2) (48 and 35%), mRNA and activities of superoxide dismutase (SOD) (63 and 40%), catalase (CAT) (56 and 31%), glutathione peroxidase (GPx) (51 and 44%), and glutathione reductase (GR) (62 and 43%), whereas marked elevations in the levels of interleukin-1 beta (IL-1β (169%), tumor necrosis factor-alfa (TNFα) (85%), nitric oxide (NO) (96%), malondialdehyde (MDA) (83%), mRNA and protein levels of Bcl-2-associated X protein (Bax) (400 and 61%), and mRNA level of caspase-3 (Cas-3) (370%). Some histopathological alterations were observed in the testicular tissue of the STZ group. In contrast, PJ markedly alleviated all the abovementioned disturbances. In conclusion, PJ at a dose of 5 mL/kg attenuated the diabetes-associated testicular impairments, which may be due to its antioxidative, anti-inflammatory, and antiapoptotic actions.
显示更多 [+] 显示较少 [-]Reducing the negative impact of ceftriaxone and doxycycline in aqueous solutions using ferrihydrite/plant-based composites: mechanism pathway 全文
2022
Olusegun, Sunday J. | Mohallem, Nelcy D. S. | Ciminelli, V. S. T.
The adsorption of ceftriaxone (CET) and doxycycline (DOX) from aqueous solution using ferrihydrite/plant-based composites (silica rice husk) to reduce their negative impact on the ecosystem was adequately studied. On the other hand, phosphate and humic acid are often found in water and soil; in view of this, their effects on the adsorption of CET and DOX were investigated. The results showed that the removal of ceftriaxone decreased with an increase in pH, while that of doxycycline did not. Ferrihydrite with 10% silica rice husk (Fh-10%SRH) has the highest maximum adsorption capacity of 139 and 178 mg g⁻¹ for CET and DOX, respectively, at room temperature based on Liu’s adsorption isotherm. This implies that the presence of silica rice husk increases CET and DOX uptake due to an increase in the pore volume of FH-10%SRH. The results showed that phosphate had a significant inhibition role on CET adsorption and minor on DOX, whereas humic acid salt affected neither case. Increase in temperature up to 333 K favored the adsorption of both contaminants. The proposed adsorption mechanisms of ceftriaxone are electrostatic interaction, n-π interaction, and hydrogen bond, while that of DOX entails n-π interaction and hydrogen bond.
显示更多 [+] 显示较少 [-]Assessing the influence of intertropical discontinuity on total column ozone variation over West Africa 全文
2022
Arowolo, Ayomide Victor | Oluleye, Ayodeji
The focus of this study is to evaluate the influence of intertropical discontinuity (ITD) on the variation of total column ozone (TCO). Relevant information is supplied on the temporal and spatial variability of TCO along the ITD zone, which is an important factor influencing the earth’s atmosphere. Several studies over the years have established the relationship and have influence several atmospheric processes on TCO. However, the relationship between intertropical discontinuity and TCO over West Africa has a gap. This study tends to examine the influence ITD has on TCO variation using the West African region as a case study. The study used wind, ozone, and dewpoint temperature data for the period between 1980 and 2019. To assess the variability and trend over the study region, several statistical methods were used, including Pearson correlation, Mann–Kendall, and linear regression model. The Mann–Kendall test shows an increasing trend throughout the months over the study region. Spatial analysis also revealed that regions north of the ITD have a higher concentration of TCO than the southern region of the ITD between April and September. However, ITD influence was more visible during the wet months of June to August (JJA) as the highest concentration of TCO was observed during this period across all latitude, but more deviation was observed between latitude 10 to 18° N, while the least occurrence is observed when ITD is at its minimum position in the month of December to February (DJF). The ACRV shows that 14° N exhibit the highest variation with a value of 4.84, while the deviation is also at its highest with value of 13.65. The monthly position of ITD for 40 years was also analysed to observe the monthly deviation along the ITD region 40 years, and the spatial distribution of TCO was analysed from January to December. It is of note that during the cause of this study, low-ozone values of 220DU are not found in the study region. The highest and the lowest value of TCO is 295 DU and 227 DU, respectively, with an average range of 68DU.
显示更多 [+] 显示较少 [-]Spatial distribution of trace elements in surface sediments of Hooghly (Ganges) river estuary in West Bengal, India 全文
2022
Trifuoggi, Marco | Ferrara, Luciano | Toscanesi, Maria | Mondal, Priyanka | Ponniah, Jonathan Muthuswamy | Sarkar, Santosh Kumar | Arienzo, Michele
The spatial distribution of trace elements in surface sediments of the Hooghly estuary was studied over the monsoons in 2014–2017. As, Cd, Ni, Pb and U were two- to sixteen-fold the crust means with increasing levels toward the estuary, with Ni peak during the post-monsoon. Pearson’s correlation matrix, cluster analysis, enrichment factors and pollution index revealed the anthropic source and association of trace elements with Fe, Mn and Al and of Pb with U. Geoaccumulation index revealed for Ni an extremely contaminated situation at the estuary water during monsoon and for Cd a heavily contaminated situation at freshwater location. The potential contamination index was >6; thus, sediments were very severely contaminated by As, Cd and Ni with worst situation for As and Cd at fresh and brackish water and during post-monsoon. The overall ecological risk was severe, 300≤RI<600 at all sites and seasons, especially after the monsoon, at fluvial and brackish locations.
显示更多 [+] 显示较少 [-]Impacts of horseradish peroxidase immobilization onto functionalized superparamagnetic iron oxide nanoparticles as a biocatalyst for dye degradation 全文
2022
Keshta, Basem E. | Gemeay, Ali H. | Khamis, Abeer A.
To enhance the dye removal efficiency by natural enzyme, horseradish peroxidase (HRP) was immobilized onto amine-functionalized superparamagnetic iron oxide and used as a biocatalyst for the oxidative degradation of acid black-HC dye. The anchored enzyme was characterized by vibrating sample magnetometry, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetry, scanning electron microscopy, Brunauer–Emmett–Teller and Barrett–Joyner–Halenda methods, nitrogen adsorption–desorption measurements, Zeta potential, energy dispersive X-ray spectroscopy, and transmission electron microscopy. The Michaelis constant values of free and immobilized HRP were determined to be 4.5 and 5 mM for hydrogen peroxide and 12.5 and 10 mM for guaiacol, respectively. Moreover, the maximum values of free and immobilized HRP were 2.4 and 2 U for H₂O₂, respectively, and 1.25 U for guaiacol. The immobilized enzyme was thermally stable up to 60°C, whereas the free peroxidase was stable only up to 40°C. In the catalytic experiment, the immobilized HRP exhibited superior catalytic activity compared with that of free HRP for the oxidative decolorization and removal of acid black-HC dye. The influence of experimental parameters such as the catalyst dosage, pH, H₂O₂ concentration, and temperature on the removal efficiency was investigated. The reaction followed second-order kinetics, and the thermodynamic activation parameters were determined.
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