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Effects of government regulations on Manufacturer’s behaviors under carbon emission reduction 全文
2019
Feng, Wei | Ji, Guojun | Pardalos, Panos M.
This paper shifts the discussion of low-carbon technology from science to the economy, especially the reactions of a manufacturer to government regulations. One major concern in this paper is uncertainty about the effects of government regulation on the manufacturing industry. On the trust side, will manufacturers trust the government’s commitment to strictly supervise carbon emission reduction? Will a manufacturer that is involved in traditional industry consciously follow a low-carbon policy? On the profit side, does equilibrium between a manufacturer and a government exist on deciding which strategy to undertake to meet a profit maximization objective under carbon emission reduction? To identify the best solutions to these problems, this paper estimates the economic benefits of manufacturers associated with policy regulations in a low-carbon technology market. The problem of an interest conflict between the government and the manufacturer is formalized as a game theoretic model, and a mixed strategy Nash equilibrium is derived and analyzed. The experiment results indicate that when the punishment levied on the manufacturer or the loss to the government is sizable, the manufacturer will be prone to developing innovative technology and the government will be unlikely to supervise the manufacturer.
显示更多 [+] 显示较少 [-]First occurrence and composition assessment of microplastics in native mussels collected from coastal and offshore areas of the northern and central Adriatic Sea 全文
2019
Gomiero, Alessio | Strafella, Pierluigi | Øysæd, Kjell Birger | Fabi, Gianna
In recent years, the occurrence of microplastics in the aquatic environment has gathered increasing scientific interest. Several studies have shown that the ingestion of microplastics may negatively influence the physiology of marine organisms having different feeding strategies, particularly in those species which cannot discriminate between food sources. Recent studies highlighted the potential for such particles to accumulate in the food web, posing risks to human health via the consumption of seafood. Furthermore, early findings also indicated the role of microplastics as vectors of chemical pollutants either used as additives during synthesis of the plastics or adsorbed directly from seawater, i.e., PAHs, PCB, and surfactants. Despite the importance of microplastics in adsorption and transport of hydrophobic pollutants, little is known about their distribution and accumulation in marine food webs, or their direct and indirect harmful effects. The Adriatic Sea represents a semi-enclosed basin with a low water recirculation rate and high anthropogenic pressures associated with unsustainable fishing and inputs of contaminants. The body burden, accumulation rates, polymer composition, and recurring morphotypes of microplastics in native blue mussels (M. galloprovincialis) were examined. Organisms collected offshore were compared to those collected in coastal areas. Microplastics were recovered from the soft tissues of all analyzed mussels. Coastal organisms showed a load of 1.06–1.33 fragments g⁻¹ (wet weight) and 0.62–0.63 fibers g⁻¹ (wet weight) while offshore organisms showed an accumulation of 0.65–0.66 fragments g⁻¹ (wet weight) and 0.24–0.35 fibers g⁻¹ (wet weight). The size class distribution revealed a marked prevalence of smaller particles (20 μm to 40 μm range) and the most recurring polymer type in analyzed organisms was PE followed by PP, PET, and equal amounts of PS, PLY, and PVC. A significant site-, time-, and oceanographic-related distribution trend was observed. Based on the findings presented here, there is a clear need to implement a seafood safety monitoring program to better understand actual human health–related risks.
显示更多 [+] 显示较少 [-]Enzyme and pH dual-responsive avermectin nano-microcapsules for improving its efficacy 全文
2019
Liu, Guanghua | Lin, Guanquan | Lin, Xida | Zhou, Hongjun | Chen, Huayao | Haoli, | Zhou, Xinhua
The overdosage use of pesticide was harmful to the environment and human health, which was mainly caused by the low utilization rate of the pesticide. However, the pesticide microcapsule with sustained-release and stimulating response properties could effectively solve this problem. Preparation of carboxymethyl cellulose grafting dimethyldiallylammonium chloride (CMC-g-PDMDAAC) through grafting polymerization and trapping as well as encapsulation of avermectin (AVM) via electrostatic interactions resulted in the formation of AVM/CMC-g-PDMDAAC microcapsules. The results showed that the particle size was 200~300 nm. The encapsulation efficiency was as high as 72.06%. Furthermore, the remaining rate of encapsulated AVM increased from 50.0 to 81.60% after UV irradiation for 359 min. The microcapsules exhibited significant enzyme and pH stimuli responsiveness. Finally, CMC-g-PDMDAAC had no significant difference effect on the toxicity of AVM, AVM could be found, and DMDAAC featured a synergistic effect on the toxicological effects of AVM. Graphical abstract
显示更多 [+] 显示较少 [-]Cadmium overload modulates piroxicam-regulated oxidative damage and apoptotic pathways 全文
2019
Abdeen, Ahmed | Abou-Zaid, Omayma A. | Abdel-Maksoud, Hussein A. | Aboubakr, Mohamed | Abdelkader, Afaf | Abdelnaby, Amany | Abo-Ahmed, Ahmed I. | El-Mleeh, Amany | Mostafa, Ola | Abdel-Daim, Mohamed | Aleya, Lotfi
Cadmium (Cd) is a common environmental pollutant that threatens humans’ and animals’ health. Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used drugs due to their wide therapeutic action; however, they have significant side effects. Since, under many circumstances, humans and animals may be co-exposed to Cd and NSAIDs, the current investigation was assigned to explore the intertwining relationship between Cd and NSAIDs. Four groups of male Wister rats were used: control group: rats received saline; Cd group: rats received cadmium (Cd, 2 mg/kg) orally; Px group: rats received a NSAID (piroxicam, Px, 7 mg/kg, i.p.); and Cd+Px group: rats received both Cd+Px. All treatments were given once a day for 28 consecutive days. Then, blood samples, stomach, liver, and kidney tissues were collected. The results indicated that Px provoked gastric ulcer indicated by high ulcer index, while Cd had no effect on the gastric mucosa. In addition, treatment with Cd or Px alone significantly induced liver and kidney injuries indicated by serum elevations of AST, ALT, ALP, ALB, total protein, creatinine, and urea along with histopathological alterations. Significant increases in malondialdehyde and reduction in GSH and CAT contents were reported along with up-regulated expression of Bax and Bcl-2 after Cd or Px exposure. However, when Cd and Px were given in a combination, Cd obviously potentiated the Px-inflicted cellular injury and death in the liver and kidney but not in the stomach when compared to their individual exposure. This study concluded that oxidative stress mechanisms were supposed to be the main modulator in promoting Cd and Px toxicities when given in combination.
显示更多 [+] 显示较少 [-]Pollutants from fish feeding recycled for microalgae production as sustainable, renewable and valuable products 全文
2019
Chan, Hing
Trash fish feeding of cage fish can result in marine pollution. Whole and chopped trash fish can leach pollutants such as ammonia, phosphate and protein into surrounding waters. Reduction of pollution can be achieved by recycling the wastewater generated from trash fish feeding for cultivation of microalgae. Microalgae are potent candidates for the production of renewable and sustainable products such as feed and food, health and pharmaceutical, cosmeceutical, industrial products, and biofuel. Two microalgae, Chlorella saccharophila and Nannochloropsis sp., have the potential to produce high amounts of polyunsaturated fatty acids. Furthermore, high oil content ranging from 10.7 to 13.6% is found in Chlorella saccharophila and up to 9.3% for Nannochloropsis sp. Moreover, these microalgae can also be utilized as a biofuel to give a mean calorific value of 5364 Cal/g which is higher than that of wood for Chlorella saccharophila and 6132 Cal/g which is equivalent to that of coal for Nannochloropsis sp. An alternative biofuel derived from microalgae is feasible due to the fact that they do not compete for arable land for cultivation and land crops for feed and food. This study discusses the synergistic coupling of microalgae mass production with wastewater treatment and carbon sequestration potential for mitigation of environmental impacts and a technically viable alternative energy resource. Additionally, the de-oiled biomass byproduct after oil extraction or its whole biomass can be converted into sustainable and renewal industrial products such as bioplastic, biopaint, bioasphalt, and biobuilding components.
显示更多 [+] 显示较少 [-]Assessment of areal water and tillage erosion using magnetic susceptibility: the approach and its application in Moroccan watershed 全文
2019
Bouhlassa, Saidati | Bouhsane, Naima
Soil erosion constitutes a serious threat for sustainable agriculture in many countries. Magnetic susceptibility of soil is a fast, cheap, and non-destructive technique that could be used to quantify soil erosion or soil redistribution on a long-term scale. This study attempts to analyze the variation of magnetic susceptibility in soil profiles having the same lithology and climatic conditions, but different land uses and slope gradients in a subcatchment in northern Morocco. Soil cores were collected on forested, cultivated, and pasture lands. Each core was associated to a field unit (also called a homogeneous unit) characterized by a set of four cited erosion factors. The samples were measured for mass–specific low-frequency magnetic susceptibility (χₗf) and frequency-dependent magnetic susceptibility (χfd). The linear correlation of χₗf and χfd indicates the homogeneity of magnetic population in soil. It supports the use of empirical models based on comparisons of χₗf to predict the value of magnetic parameter after tillage homogenization and removal of soil material from the surface, and to estimate soil erosion or redeposition. The study built a methodology improving these empirical models and enabling a quantitative approach of the phenomenon. Two models, namely “tillage homogenization” (as improved in this study) and the proposed “simple correlation” result in globally similar estimates of erosion, while another model, the “simple proportional” model, underestimates it. The results give an estimate of long-term erosion (deposition) in sampled units and allow drawing of an areal soil redistribution map in the watershed.
显示更多 [+] 显示较少 [-]Environmental factors affecting the frequency of road traffic accidents: a case study of sub-urban area of Pakistan 全文
2019
Hammad, Hafiz Mohkum | Ashraf, Muhammad | Abbas, Farhat | Bakhat, Hafiz Faiq | Qaisrani, Saeed A. | Mubeen, Muhammad | Shah, Fahad | Awais, Muhammad
Road traffic accidents (RTAs) are among the life-threatening issues facing rural as well as sub-/urban communities. Several factors contribute to RTAs ranging from human to technical and natural/environmental impacts. Anthropogenic air pollution and corresponding environmental factors also increase the probability of RTAs. Current study reports the relationship of the weather conditions to RTAs. The study establishes the relevancy of different weather conditions like rainfall, temperature, fog, and wind storm with the incidences of RTAs in rural and urban settings of Vehari, Punjab—Pakistan. The results of the study showed that rainfall, severe coldness, fog, and heat conditions were directly related with the occurrence of RTAs. The percentage of RTAs which occurred due to fog, rainfall, temperature, and other weather-related factors was 34, 25, 21, and 20%, respectively. The age of the driver significantly correlated (R² = 0.60) with RTAs; the drivers in the age group 40–60 years caused the least RTAs during their drive. Since the smaller vehicles were involved in maximum RTAs, it relates negatively (R² = 0.82) to vehicles power. Among different vehicles motor bikes were involved in most (42%) of the reported RTAs. Therefore, during severe weather conditions, vehicles with smaller size and young drivers must be dealt with carefully while interacting (crossing, overtaking, and maneuvering) on the roads regardless of rural or urban conditions. Factors including civic sense, traffic education, vehicle size, drivers’ maturity, road conditions, and environmental impacts may be considered while designing traffic rules and traffic aware campaigns specific for developing countries such as Pakistan.
显示更多 [+] 显示较少 [-]Empirics on influencing mechanisms among energy, finance, trade, environment, and economic growth: a heterogeneous dynamic panel data analysis of China 全文
2019
Ahmad, Munir | Zhao, Zhen-Yu | Irfan, Muhammad | Mukeshimana, Marie Claire
The current study empirically examines the influencing mechanisms among energy consumption, financial development, international trade, environment, and economic growth for 29 Chinese provinces and cities for periods 1997 to 2016. A new augmented growth model has been developed, introducing financial development as a shift factor of aggregate production, international trade as determinant of total factor productivity, and energy consumption as input of production function. The key empirical findings include (1) financial development exposed dual nature in terms of its influence on energy consumption and carbon emissions. Banking-based financial development is revealed to add in energy consumption and carbon emissions, while stock market–based financial development curtailed energy consumption and mitigated the carbon emissions, improving the environmental quality, (2) GDP growth is uncovered to add to international trade with varying magnitudes in all samples; however international trade imparted negative to neutral to positive influence on GDP growth in W-region, C-region, and E-region, respectively. It is named as competitiveness driven growth deceleration/neutrality/acceleration influence. It states that as regions/countries develop, the domestic industry gets competitive in international trade markets; consequently, the influence of international trade on economic growth transforms from negative to neutral to positive, (3) both type of financial development measures imparted significant positive influence on GDP growth which confirms the Schumpeterian view to be valid in regional China, (4) based on causality from quadratic terms of GDP, international trade, and financial development ratio to carbon emissions growth confirm the existence of conventional EKC as well as international trade and financial development based EKC in all regions except W-region for which conventional EKC and international trade based EKC are not confirmed. Finally, based on empirical influencing mechanisms, the relevant policies are recommended.
显示更多 [+] 显示较少 [-]Does macroeconomic instability cause environmental pollution? The case of Pakistan economy 全文
2019
Khan, Muhammad
This study aims to investigate the relationship between carbon dioxide (CO₂) emissions, macroeconomic instability, real output (GDP), the square of real output (GDP²), and financial development in Pakistan using the annual dataset over the period 1971–2016. The long-run analysis is based on the ARDL bound testing approach to cointegration, whereas the short-run dynamics are observed using error correction model. The results of the bound testing approach indicate that there exists a long-run relationship between the selected variables and macroeconomic instability increases pollution emissions. In addition, the study supports the presence of environmental Kuznets curve (EKC) hypothesis for Pakistan economy where, in low-income regime, an increase in GDP causes more emissions and, in high-income regime, the relationship between GDP and CO₂ emissions becomes negative. Finally, financial development variables exert a positive impact on environmental degradation. Based on these findings, our study supports a strong role of macroeconomic stability in achieving the targets of pollution reductions.
显示更多 [+] 显示较少 [-]Impact assessment of land use change on surface temperature and agricultural productivity in Peshawar-Pakistan 全文
2019
Khan, Imran | Javed, Tehseen | Khan, Ahmad | Lei, Hongdou | Muhammad, Ihsan | Ali, Imad | Huo, Xuexi
The profound appreciation of urban expansion and land use change (LUC) considerably influences the ecosystem functions, services, and biodiversity along with the local and regional climate. Land use has undergone an awful transformation due to rapid urbanization and population growth, which in turn increased land surface temperature (LST) in district Peshawar, Pakistan. The current study tends to capture the influence of land use on LST and agricultural productivity by employing multi-temporal, multispectral satellite data and agricultural production data during the selected years, i.e., 1996, 2003, and 2016. The results demonstrated that barren land considerably decreased while the urban area increased over time in all three phases. Furthermore, significant LST difference was found in different land cover units; e.g., barren land and urban area have the maximum, while water bodies followed by vegetation retain minimum LST in all three phases, i.e., 1996, 2003, and 2016. Similarly, the results from agricultural production revealed that except for wheat crops, which decreased by 7.54% during 1999–2003, the production of all major food crops increased during the selected years. However, the production of sugar cane and barley experienced considerable reduction during the selected years, except for barley, which increased by 22.86% during 2003–2016. The finding of this study provides guidance, policy recommendations, and reference for future researchers. Graphical abstract .
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