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Rapid increases of energy consumption and human dependency on fossil fuels have led to the accumulation of greenhouse gases and consequently, climate change. As such, major efforts have been taken to develop, test, and adopt clean renewable fuel alternatives. Production of bioethanol and biodiesel from crops is well developed, while other feedstock resources and processes have also shown high potential to provide efficient and cost-effective alternatives, such as landfill and plastic waste conversion, algal photosynthesis, as well as electrochemical carbon fixation. In addition, the downstream microbial fermentation can be further engineered to not only increase the product yield but also expand the chemical space of biofuels through the rational design and fine-tuning of biosynthetic pathways toward the realization of "designer fuels" and diverse future applications.
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Biocombustíveis/análise , Desenvolvimento Sustentável , Vias Biossintéticas , Ciclo do Carbono , Humanos , Lignina/metabolismo , ResíduosRESUMO
The Na3 [Ru2 (µ-CO3 )4 ] complex is acting as a water oxidation catalyst in a homogeneous system. Due to the significance of heterogeneous systems and the effect of bicarbonate on the kinetic, we studied the bicarbonate effect on the heterogeneous electrocatalyst by entrapping the Na3 [Ru2 (µ-CO3 )4 ] complex in a sol-gel matrix. We have developed two types of sol-gel electrodes, which differ by the precursor, and are demonstrating their stability over a minimum of 200 electrochemical cycles. The pH increases affected the currents and kcat for both types of electrodes, and their hydrophobicity, which was obtained from the precursor type, influenced the electrocatalytic process rate. The results indicate that NaHCO3 has an important role in the catalytic activity of the presented heterogeneous systems; without NaHCO3 , the diffusing species is probably OH- , which undergoes diffusion via the Grotthuss mechanism. To the best of our knowledge, this is the first study to present a simple and fast one-step entrapment process for the Na3 [Ru2 (µ-CO3 )4 ] complex by the sol-gel method under standard laboratory conditions. The results contribute to optimizing the WSP, ultimately helping expand the usage of hydrogen as a green and more readily available energy source.
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International demand for wood and other forest products continues to grow rapidly, and uncertainties remain about how animal communities will respond to intensifying resource extraction associated with woody bioenergy production. We examined changes in alpha and beta diversity of bats, bees, birds, and reptiles across wood production landscapes in the southeastern United States, a biodiversity hotspot that is one of the principal sources of woody biomass globally. We sampled across a spatial gradient of paired forest land-uses (representing pre and postharvest) that allowed us to evaluate biological community changes resulting from several types of biomass harvest. Short-rotation practices and residue removal following clearcuts were associated with reduced alpha diversity (-14.1 and -13.9 species, respectively) and lower beta diversity (i.e., Jaccard dissimilarity) between land-use pairs (0.46 and 0.50, respectively), whereas midrotation thinning increased alpha (+3.5 species) and beta diversity (0.59). Over the course of a stand rotation in a single location, biomass harvesting generally led to less biodiversity. Cross-taxa responses to resource extraction were poorly predicted by alpha diversity: correlations in responses between taxonomic groups were highly variable (-0.2 to 0.4) with large uncertainties. In contrast, beta diversity patterns were highly consistent and predictable across taxa, where correlations in responses between taxonomic groups were all positive (0.05-0.4) with more narrow uncertainties. Beta diversity may, therefore, be a more reliable and information-rich indicator than alpha diversity in understanding animal community response to landscape change. Patterns in beta diversity were primarily driven by turnover instead of species loss or gain, indicating that wood extraction generates habitats that support different biological communities.
Conservación de la Diversidad Alfa y Beta en Paisajes de Producción Maderera Resumen La demanda internacional de madera y otros productos forestales sigue creciendo rápidamente mientras permanecen las incertidumbres sobre cómo responderán las comunidades animales a la intensificación de la extracción de recursos asociada con la producción de bioenergía leñosa. Examinamos los cambios en la diversidad alfa y beta de murciélagos, abejas, aves y reptiles en los paisajes de producción maderera en el sureste de los Estados Unidos, un punto caliente de biodiversidad y una de las fuentes principales de biomasa leñosa a nivel mundial. Muestreamos a lo largo de un gradiente espacial de usos de suelo forestales emparejados (representando la pre- y postcosecha) que nos permitió evaluar los cambios en las comunidades biológicas resultantes de varios tipos de recolección de biomasa. Las prácticas de corta rotación y de eliminación de residuos después de la tala estuvieron asociadas con la reducción de la diversidad alfa (−14.1 y −13.9 especies, respectivamente) y una diversidad beta más baja (es decir, diferencia de Jaccard) entre los pares de uso de suelo (0.46 y 0.50, respectivamente), mientras que el raleo de rotación media incrementó la diversidad alfa (+3.5 especies) y beta (0.59). Durante la duración de una rotación permanente en una sola ubicación, la cosecha de biomasa generalmente derivó en menos biodiversidad. La respuesta de los taxones a la extracción de recursos estuvo muy mal pronosticada por la diversidad alfa: la correlación de las respuestas entre los grupos taxonómicos fue altamente variable (−0.2 a 0.4) con muchas incertidumbres. Como contraste, los patrones de diversidad beta fueron fuertemente coherentes y predecibles en todos los taxones, mientras que la correlación de las respuestas entre los grupos taxonómicos siempre fue positiva (0.05 a 0.4) con incertidumbres más limitadas. Por lo tanto, la diversidad beta puede ser un indicador más confiable y rico en información que la diversidad alfa para entender las respuestas de la comunidad animal a los cambios en el paisaje. Los patrones de la diversidad beta estuvieron impulsados principalmente por la rotación en lugar de la pérdida o ganancia de especies, lo que indica que la extracción de madera genera hábitats que mantienen a diferentes comunidades biológicas.
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Conservação dos Recursos Naturais , Madeira , Animais , Biodiversidade , Ecossistema , FlorestasRESUMO
Despite multiple approaches over the last several decades to harmonize conservation and development goals in the tropics, forest-dependent households remain the poorest in the world. Durable housing and alternatives to fuelwood for cooking are critical needs to reduce multi-dimensional poverty. These improvements also potentially reduce pressure on forests and alleviate forest degradation. We test this possibility in dry tropical forests of the Central Indian Highlands where tribal and other marginalized populations rely on forests for energy, construction materials, and other livelihood needs. Based on a remotely sensed measure of forest degradation and a 5000 household survey of forest use, we use machine learning (causal forests) and other statistical methods to quantify treatment effects of two improved living standards-alternatives to fuelwood for cooking and non-forest-based housing material-on forest degradation in 1, 2, and 5 km buffers around 500 villages. Both improved living standards had significant treatment effects (-0.030 ± 0.078, -0.030 ± 0.023, 95% CI), respectively, with negative values indicating less forest degradation, within 1 km buffers around villages. Treatment effects were lower with increasing distance from villages. Results suggest that improved living standards can both reduce forest degradation and alleviate poverty. Forest restoration efforts can target improved living standards for local communities without conflicts over land tenure or taking land out of production to plant trees.
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Ambient pressure hydro-deoxygenation (HDO) of the phenolic-rich pyrolysis liquid fraction is a complex task due to the presence multiple phenolic compounds and light oxygenates. The phenolic-rich fraction differs from the overall pyrolysis liquid, known to be prone to re-polymerization and coking in the reactor or of the catalyst. In the present research, hydro-deoxygenation of oxygen-containing compounds in the phenolic fraction over Mo-based catalysts was carried out for the first time. It was found that Mo-based catalysts can successfully upgrade the phenolics into aromatics, the conversion rate was nearly 100%. The small amount of light oxygenates in the phenolic-rich fraction had no obvious effect on the hydro-deoxygenation reaction, the phenolic conversion was more than 95%. After assessing the performance for a representative phenolic model compound, the reaction was also successfully carried out on the phenolic fraction of the real pyrolysis liquid. It can be concluded that the catalysts can also be used for the HDO of the real pyrolysis liquid fraction at atmospheric pressure.
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Coque , Pirólise , Pressão Atmosférica , Biomassa , Catálise , Temperatura Alta , FenóisRESUMO
Our paper proposes a novel measure of global energy market uncertainty and studies its impact on oil prices. The current literature primarily relies on a single or small number of observable variables, or general macroeconomic uncertainty (JLN) and economic policy uncertainty (EPU) indices to reflect energy market uncertainty. Using a Factor Augmented Vector Autoregression model (FAVAR), we construct time-varying global energy market uncertainty in a data-rich environment. Our estimates show variations from JLN and EPU proxies. The results reveal that real oil prices respond strongly to our proposed aggregate energy market uncertainty shocks. We also find heterogeneous responses to different types and magnitudes of uncertainty shocks. The real price of oil is affected the most under unexpected strong demand for alternative energy sources scenario.
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Petróleo , IncertezaRESUMO
The production of chemicals and fuels from renewable biomass with the primary aim of reducing carbon footprints has recently become one of the central points of interest. The use of lignocellulosic biomass for energy production is believed to meet the main criteria of maximizing the available global energy source and minimizing pollutant emissions. However, before usage in bioenergy production, lignocellulosic biomass needs to undergo several processes, among which biomass pretreatment plays an important role in the yield, productivity, and quality of the products. Acid-based pretreatment, one of the existing methods applied for lignocellulosic biomass pretreatment, has several advantages, such as short operating time and high efficiency. A thorough analysis of the characteristics of acid-based biomass pretreatment is presented in this review. The environmental concerns and future challenges involved in using acid pretreatment methods are discussed in detail to achieve clean and sustainable bioenergy production. The application of acid to biomass pretreatment is considered an effective process for biorefineries that aim to optimize the production of desired products while minimizing the by-products.
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Biocombustíveis , Lignina , Biomassa , Fontes Geradoras de EnergiaRESUMO
The use of heating systems for new-born piglets can prevent major losses in the first 5 weeks of life. The present study had the objective of evaluating three heating systems in creeps for new-born piglets, being: floor-heated floor with circulating water (HF), incandescent lamp type SPOT 40 W (L) and incandescent lamp type SPOT 40 W plus black metal plate (LP). The variables evaluated were piglet performance (total weight gain and mortality), bioclimatic data (temperature and relative air humidity), animal behaviour and economic revenue. Bioclimatic data were recorded in the external environment, in the maternity and in the interior of each shelter/creep for 21 days, three times a day, as well as the capture of photographic images for analysis of the animals' disposal. The mean temperature of the retractors, the weight at weaning and the weight gain were higher in the HF treatment. Treatment HF improved the percentage of dispersed animals and provided the best thermal environment and the highest revenue at the time of the commercialization of the piglets.
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Calefação , Aumento de Peso , Animais , Animais Recém-Nascidos , Peso Corporal , Feminino , Humanos , Gravidez , Suínos , Temperatura , DesmameRESUMO
We use dip-pen nanolithography to accurately pattern Ni(OH)2 nanoclusters on a metachemical surface with an exceptionally large surface area. The distance between the nanoclusters can be manipulated to control the oxygen-evolution reaction current and overpotential, thereby improving the efficiency of the water-splitting process while using minute amounts of the catalyst.
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Hidróxidos/química , Níquel/química , Água/química , Nanopartículas/ultraestrutura , Oxirredução , Tamanho da Partícula , Propriedades de SuperfícieRESUMO
Fabric-based microfluidic fuel cells (MFCs) serve as a novel, cost-efficient alternative to traditional FCs and batteries, since fluids naturally travel across fabric via capillary action, eliminating the need for an external pump and lowering production and operation costs. Building on previous research with Y-shaped paper-based MFCs, fabric-based MFCs mitigate fragility and durability issues caused by long periods of fuel immersion. In this study, we describe a microfluidic fabric-based direct formate fuel cell, with 5 M potassium formate and 30% hydrogen peroxide as the anode fuel and cathode oxidant, respectively. Using a two-strip, stacked design, the optimized parameters include the type of encasement, the barrier, and the fabric type. Surface contact of the fabric and laminate sheet expedited flow and respective chemical reactions. The maximum current (22.83 mA/cm2 ) and power (4.40 mW/cm2 ) densities achieved with a 65% cotton/35% polyester blend material are a respective 8.7% and 32% higher than previous studies with Y-shaped paper-based MFCs. In series configuration, the MFCs generate sufficient energy to power a handheld calculator, a thermometer, and a spectrum of light-emitting diodes.
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Fontes de Energia Elétrica/tendências , Formiatos , Microfluídica/instrumentação , Têxteis , Fontes de Energia Elétrica/economia , Desenho de Equipamento , Peróxido de Hidrogênio/química , Microfluídica/métodos , PapelRESUMO
Mitigation translocation of nuisance animals is a commonly used management practice aimed at resolution of human-animal conflict by removal and release of an individual animal. Long considered a reasonable undertaking, especially by the general public, it is now known that translocated subjects are negatively affected by the practice. Mitigation translocation is typically undertaken with individual adult organisms and has a much lower success rate than the more widely practiced conservation translocation of threatened and endangered species. Nonetheless, the public and many conservation practitioners believe that because population-level conservation translocations have been successful that mitigation translocation can be satisfactorily applied to a wide variety of human-wildlife conflict situations. We reviewed mitigation translocations of reptiles, including our own work with 3 long-lived species (Gila monsters [Heloderma suspectum], Sonoran desert tortoises [Gopherus morafkai], and western diamond-backed rattlesnakes [Crotalus atrox]). Overall, mitigation translocation had a low success rate when judged either by effects on individuals (in all studies reviewed they exhibited increased movement or increased mortality) or by the success of the resolution of the human-animal conflict (translocated individuals often returned to the capture site). Careful planning and identification of knowledge gaps are critical to increasing success rates in mitigation translocations in the face of increasing pressure to find solutions for species threatened by diverse anthropogenic factors, including climate change and exurban and energy development.
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Conservação dos Recursos Naturais/métodos , Espécies em Perigo de Extinção , Répteis/fisiologia , Animais , Arizona , Crotalus/fisiologia , Lagartos/fisiologia , Tartarugas/fisiologiaRESUMO
OBJECTIVE: This study examined the effects of substituting winged bean tuber steam (WBTS) modified starches for cassava chips (CSC) in the concentrate diet on rumen fermentation, nutrient utilization, and blood metabolites in Thai-native beef cattle. METHODS: Four Thai-native bulls were assigned randomly as a 4×4 Latin square design, which represents the amount of CSC replaced with WBTS in the concentrate mixture diets at 0%, 10%, 20%, and 30%. RESULTS: Increasing levels of WBTS replacement for CSC in the concentrate diets had a quadratic effect on total dry matter (DM) intake (p<0.05). Replacement of WBTS at 20% and 30% for CSC did not alter total DM intake compared to 0% WBTS, whereas 10% WBTS replacement could significantly increase total DM intake by 0.41 kg DM/d compared to the control group. In addition, neutral detergent fiber (NDF) digestibility showed a quadratic increase (p<0.05) when CSC was substituted at various levels of WBTS in the concentrate diet (p<0.05). Replacement of CSC with WBTS at 10% and 20% showed higher NDF digestibility when compared to 0% replacement. There was a quadratic increase in blood glucose at 4 h post-feeding, and the average blood glucose value was significantly lower (p<0.01) when substituting CSC with WBTS. Substituting WBTS for CSC at 10% in the concentrate diet showed the highest blood glucose concentration when compared to other treatments. Replacing CSC with WBTS at 10% and 20% shows a higher concentration of C3 than those of other treatments (0% or 30%). The nitrogen (N) intake increased linearly (p<0.05) when substituting WBTS for CSC at all levels in the diet. Additionally, N retention and the ratio of N retention to N intake increased (p<0.05) when substituting WBTS for CSC at 10%, 20%, and 30% compared to 0%. The gross energy intake (GEI), digestible energy intake (DEI), and energy efficiency (DEI/GEI) were quadratically increased when substituted with various levels of WBTS for CSC in the concentrate diet. CONCLUSION: The findings indicate that substituting 10% of CSC in the concentrate diet with WBTS may be sufficient as an alternative feed resource for improving nutrient utilization and metabolic efficiency in beef cattle diets.
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Greenhouse gases (GHGs) are the primary drivers of global climate change. Human activities, particularly those related to energy production, transportation, and industry, have long contributed to the escalating levels of GHGs in the Earth's atmosphere. Recognizing the significance of this issue, universities, including Thammasat University, play a vital role in Greenhouse gas (GHG) emissions research and education, carrying a responsibility to address the matter. This study is aimed aims to assess the greenhouse gas emissions and mitigation measures at Thammasat University (Lampang campus), Thailand. The emissions are categorized into 3 types: (1) direct GHG emissions; (2) energy-related indirect GHG emissions; and (3) other indirect GHG emissions. Activity data from the years 2019 to 2022 was used for the calculations, resulting in GHG emissions of 1051.70, 778.28, 558.64, and 1034.531 tons of carbon dioxide equivalent. Among these emissions, energy-related indirect GHG emissions from electricity purchases represent the majority, accounting for approximately 78.55% of the total emissions. Consequently, implementing mitigation strategies, such as solar panel installations and solid waste reduction (combined scenario), has the potential to reduce GHG emissions by up to 57.78%. Furthermore, the university should actively promote GHG emissions reduction through the enactment of energy-saving policies and the adoption of energy-efficient technologies to reduce reliance on energy purchases.
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Nanotechnology has emerged as a revolutionary technology that has been applied in the oil and gas industry for over a decade, spanning the upstream, midstream, and downstream sectors. Nanotechnology has made significant contributions to the exploration of crude oil and natural gas, both in underground and deep-water environments. It has also played a crucial role in improving the drilling process, enabling the extraction of oil and gas resources from beneath the Earth's surface. Nanoparticles, with their unique physical and chemical properties, such as high specific surface area, high pore volume, and small size, have demonstrated considerable potential in the oil industry. Extensive research has been conducted to explore various types of nanoparticles for advanced applications, including oil exploration, drilling, production, and enhanced oil recovery (EOR). Moreover, nanomaterials have found applications in downstream and intermediate sectors, such as crude oil refining, natural gas processing, and transportation and storage of petroleum products. Ongoing advancements in nanomaterial synthesis methods, the exploration of new nanomaterial uses, and understanding the remarkable properties of nanomaterials will continue to make them increasingly valuable in the oil and gas sector. The oil and gas industry recognises the potential of nanotechnology and nanoparticles and is investing significantly in research and development in this area. This comprehensive review aims to summarise successful applications of nanotechnology while addressing associated challenges. It serves as a valuable resource for future research and application endeavours in the field, highlighting the potential of nanotechnology in the oil and gas industry.
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Nanoestruturas , Petróleo , Gás Natural , Indústrias , TecnologiaRESUMO
ß-hydroxybutyrate (BHB) is a ketone body that serves as an alternative energy source for various tissues, including the brain, heart, and skeletal muscle. As a metabolic intermediate and signaling molecule, BHB plays a crucial role in modulating cellular and physiological processes. Notably, BHB supplementation offers a novel and promising strategy to induce nutritional ketosis without the need for strict dietary adherence or causing nutritional deficiencies. This review article provides an overview of BHB metabolism and explores its applications in age-related diseases. This review conducted a comprehensive search of PubMed, ScienceDirect, and other relevant English-language articles. The main findings were synthesized, and discussed the challenges, limitations, and future directions of BHB supplementation. BHB supplementation holds potential benefits for various diseases and conditions, including neurodegenerative disorders, cardiovascular diseases, cancers, and inflammation. BHB acts through multiple mechanisms, including interactions with cell surface receptors, intracellular enzymes, transcription factors, signaling molecules, and epigenetic modifications. Despite its promise, BHB supplementation faces several challenges, such as determining the optimal dosage, ensuring long-term safety, identifying the most effective type and formulation, establishing biomarkers of response, and conducting cost-effectiveness analyses. BHB supplementation opens exciting avenues for research, including investigating molecular mechanisms, refining optimization strategies, exploring innovation opportunities, and assessing healthspan and lifespan benefits. BHB supplementation represents a new frontier in health research, offering a potential pathway to enhance well-being and extend lifespan.
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Wind energy appears to place global environmental benefits against local human health, particularly sleep. The result is a significant challenge to wind-energy development for the achievement of large-scale alternative energy. Our purpose is to examine noise from wind turbines and its potential to disrupt sleep, to examine the human health literature addressing these concerns, and to provide insight into how developers and communities can employ these concepts to pursue wind energy without impacting human health. The latest and most rigorous research on noise from wind turbines points to healthy sleep, when turbines are sited reasonably. This includes audible noise, low-frequency noise, and infrasound. Recent advances in acoustical standards provide practical methods to ensure adherence to these scientific findings. There now exist key data concerning wind-turbine noise, and its impact on sleep. Knowing that information, and how to deploy it with modern engineering standards should simultaneously facilitate wind development and protect human health.
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Ruído , Transtornos do Sono-Vigília , Humanos , Ruído/efeitos adversos , Sono , AcústicaRESUMO
The renewable-energy-based water-energy nexus is a promising approach that contributes to climate change mitigation. Increasing concerns on GHG emission and energy demand, policies have been implemented in many countries to make use of renewable energy as much as possible. Renewable energy technologies can be directly employed in desalination processes, including membrane-based (e.g., reverse osmosis (RO) and membrane distillation (MD)) and thermal-based (e.g., multistage flash distillation (MSF) and multieffect distillation (MED)) technologies. Although the production capacities of fossil-based desalination processes (RO, MD, and MED) are higher than those of renewable-energy-based desalination processes, most latter desalination processes have lower specific energy consumption than conventional processes, which may offer potential for the implementation of renewable energy sources. In addition to the direct application of renewable energy technology to desalination, biofuels can be produced by converting algal lipids obtained from the growth of algae, which are associated with wastewater bioremediation and nitrogen and phosphorus removal during wastewater treatment. Salinity gradient power can be harvested from brine originating from desalination plants and freshwater driven by pressure-retarded osmosis or reverse electrodialysis. This study provides an overview of these approaches and discusses their effectiveness. It not only offers insights into the potential of applying renewable energy technologies to various water treatment processes but also suggests future directions for scientists to further enhance the efficiency of renewable energy production processes for possible implementation.
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Energia Renovável , Purificação da Água , Purificação da Água/métodos , Biocombustíveis , Osmose , Salinidade , Águas Residuárias/químicaRESUMO
The world faces several problems related to natural gas resource rents and energy production from renewable sources. One of the main problems is the influence of energy imports, manufacturing exports, and alternative energy sources on natural gas and electricity production from renewable sources. Energy imports, manufacturing exports, and alternative energy sources can impact natural gas and electricity production. This paper examines natural gas resource rents and electricity production from renewable sources nexus from 1971 to 2021, using energy imports, manufacturer's exports, and alternative energy sources in China. Electricity production from renewable sources and manufacturing exports are negatively associated with natural gas resource rents. Energy imports and alternative energy sources positively relate to natural gas resource rents in China. These results suggest that the energy sector in China is highly interconnected and that policies that seek to promote renewable energy sources and other alternatives can positively affect natural gas resource rents. China needs to develop an energy policy considering the policy implications of energy imports and natural gas resource rents. Such a policy should focus on increasing domestic production, reducing energy imports, and ensuring adequate revenue from natural gas resource rents. Additionally, regulations could be implemented that support the development of alternative energy sources, such as requiring utilities to purchase a certain percentage of their power from renewable sources.
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Eletricidade , Gás Natural , Energia Renovável , China , Energia NuclearRESUMO
The global community is concerned about several environmental changes. Climate change, desertification, destruction of tropical rainforests, erosion of coastal ecosystems, soil resource loss, overfishing, species extinction, and loss of biodiversity are all contributing factors. Many commentators contend that these issues make up a cumulative, sustained human impact on the environment that has profoundly changed the surface of the Earth. We explore the effects of alternative energy sources, natural resources, and government consumption expenditures on French environmental sustainability from 1990 through 2018 under the environmental Kuznets curve (EKC) framework. We apply advanced econometric methodologies for empirical analysis. Our long-run estimates indicate that alternative and nuclear energy, natural resources, and government final consumption expenditures are negatively associated with CO2 emissions, while economic growth is positively related to CO2 emissions. CO2 emissions are negatively correlated with the square root of economic growth (EKC), thereby supporting EKC. As economic growth increases, environmental sustainability deteriorates. Eventually, EKC will make a positive contribution to environmental improvement. Future research directions, research limitations, and policy implications are discussed.
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Conservação dos Recursos Naturais , Ecossistema , Humanos , Dióxido de Carbono/análise , Gastos em Saúde , Pesqueiros , Desenvolvimento Econômico , França , Energia Renovável , Recursos Naturais , GovernoRESUMO
Global warming is pressuring policymakers to change climate policies in shifting the global economy onto a net-zero pathway. While financial assets are responsive to policy changes and development, climate change policies are becoming increasingly unpredictable, making policy decision less certain. This study investigates connectedness and spillover effects of US climate policy uncertainty on energy stocks, alternative energy stocks, and carbon emissions futures. We analyzed spillover and connectedness before and after the Paris Agreement. We employed monthly frequency data from August 2005 to March 2021 and applied DY (2012) method and MGARCH approach. We found that world energy stocks and carbon emissions futures are connected to US climate policy uncertainty. Uncertainty in climate policy and world energy stocks act as information transmitters in return spillover, while global alternative energy and carbon market are shock receivers. On volatility spillover, climate policy uncertainty, energy stocks, and carbon emissions future are shocks transmitters, while alternative energy stocks are receivers. We observe increase in connectedness following the Paris Agreement suggesting strengthened global efforts in tackling climate change. DCC and ADCC estimations revealed spillover effects of climate policy on futures returns and volatilities of world energy stocks and carbon emissions futures and the shocks could be transmitted through to the energy sector. During period of uncertainty in US climate policy, carbon allowances can potentially serve as a safe haven for energy stocks and provide downside protection for alternative energy stocks, hence hedging against climate transition risks.