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281.

This paper analyzes the impact of international oil price uncertainty on the different economic sectors (primary, secondary, and tertiary) in Mexico in the period 1993:1–2020:4 through a bivariate structural vector autoregressive (VAR) model with a generalized autoregressive conditional heteroskedasticity (GARCH) in mean to capture the impact of oil volatility on economic growth at the sectoral level of economic activity. The results show that the uncertainty of the international price of oil has a differentiated effect on the different sectors of economic activity in Mexico since it does not influence the primary sector; it negatively impacts the secondary sector, and there is mixed evidence in the tertiary sector. Additionally, evidence is provided that both positive and negative shocks to the international oil price have asymmetric effects at the sectoral level in Mexico. The results highlight the need to implement public policies, at the country level, that help mitigate the effect of uncertainty in the oil market and promote economic stability at the sector level.

  相似文献   
282.
Environmental Science and Pollution Research - China, being the world’s largest exporter, has now certain environmental commitments such as to achieve carbon neutrality before 2060. These...  相似文献   
283.
Environmental Science and Pollution Research - Global warming and climate change have become one of the most embarrassing and explosive problems/challenges all over the world, especially in...  相似文献   
284.
Environmental Science and Pollution Research - This paper investigates the effect of different categories of essential COVID-19 data from 2020 to 2021 towards stock price dynamics and options...  相似文献   
285.
Environmental Science and Pollution Research - In the contemporary era, it is evident that consumption-based carbon emissions (CCO2e), adjusted for international trade, are a more accurate and...  相似文献   
286.
Environmental Modeling & Assessment - Analyzing the geographical distribution of carbon dioxide (CO2) is essential for understanding the influence and structural nature of area-specific...  相似文献   
287.
Journal of Polymers and the Environment - Recently, the advantages of biopolymers over conventional plastic polymers are unprecedented, provided that they are used in situations in which they raise...  相似文献   
288.
Journal of Polymers and the Environment - Modification of cellulose with silver nanoparticles produces various nanocomposites with significantly developed properties. This work aims to prepare a...  相似文献   
289.
Trichloroethene (TCE) degradation by Fe(III)-activated calcium peroxide (CP) in the presence of citric acid (CA) in aqueous solution was investigated. The results demonstrated that the presence of CA enhanced TCE degradation significantly by increasing the concentration of soluble Fe(III) and promoting H2O2 generation. The generation of HO? and O2-? in both the CP/Fe(III) and CP/Fe(III)/CA systems was confirmed with chemical probes. The results of radical scavenging tests showed that TCE degradation was due predominantly to direct oxidation by HO?, while O2-? strengthened the generation of HO? by promoting Fe(III) transformation in the CP/Fe(III)/CA system. Acidic pH conditions were favorable for TCE degradation, and the TCE degradation rate decreased with increasing pH. The presence of Cl-, HCO3-, and humic acid (HA) inhibited TCE degradation to different extents for the CP/Fe(III)/CA system. Analysis of Cl- production suggested that TCE degradation in the CP/Fe(III)/CA system occurred through a dechlorination process. In summary, this study provided detailed information for the application of CA-enhanced Fe(III)-activated calcium peroxide for treating TCE contaminated groundwater.  相似文献   
290.
Concentrations of ten metals (As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn and Hg) in the edible muscle of Arius maculatus captured from eight different near‐shore and off‐shore sites off the south west coast of the Arabian Sea, Pakistan, were determined by atomic absorption spectrophotometry. Relevant water and sediment samples from the sites were also analysed for the metals. Zinc showed the highest metal concentration (6.763 μg/g, wet weight) in the muscle of the fish, while Mn and Hg showed lowest level (0.019 μg/g, wet weight). Of all the metals investigated, largest scatter (measured as σ) was observed for Zn = 2.058 /μg/g) in fish muscle, for Fe and Mn in sediment (σ = 27481 and 44.50 μg/g) and for As in water (σ = 0.270 μg/L). The metal distribution data pertaining to water, fish and sediment were examined on the basis of simple metal correlations. The statistical study revealed that Ni, Cr, Pb and Cu had significant positive correlations (r > 0.830 at ρ = 0.01). The finding substantiated a trace metal concentration gradient in the area, thereby indicating that the local marine environment is contaminated by anthropogenic sources.  相似文献   
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