The global shift from a fossil fuel-based to an electrical-based society is commonly viewed as an ecological improvement. However, the electrical power industry is a major source of carbon dioxide emissions, and incorporating renewable energy can still negatively impact the environment. Despite rising research in renewable energy, the impact of renewable energy consumption on the environment is poorly known. Here, we review the integration of renewable energies into the electricity sector from social, environmental, and economic perspectives. We found that implementing solar photovoltaic, battery storage, wind, hydropower, and bioenergy can provide 504,000 jobs in 2030 and 4.18 million jobs in 2050. For desalinization, photovoltaic/wind/battery storage systems supported by a diesel generator can reduce the cost of water production by 69% and adverse environmental effects by 90%, compared to full fossil fuel systems. The potential of carbon emission reduction increases with the percentage of renewable energy sources utilized. The photovoltaic/wind/hydroelectric system is the most effective in addressing climate change, producing a 2.11–5.46% increase in power generation and a 3.74–71.61% guarantee in share ratios. Compared to single energy systems, hybrid energy systems are more reliable and better equipped to withstand the impacts of climate change on the power supply.
相似文献Traditional fertilizers are highly inefficient, with a major loss of nutrients and associated pollution. Alternatively, biochar loaded with phosphorous is a sustainable fertilizer that improves soil structure, stores carbon in soils, and provides plant nutrients in the long run, yet most biochars are not optimal because mechanisms ruling biochar properties are poorly known. This issue can be solved by recent developments in machine learning and computational chemistry. Here we review phosphorus-loaded biochar with emphasis on computational chemistry, machine learning, organic acids, drawbacks of classical fertilizers, biochar production, phosphorus loading, and mechanisms of phosphorous release. Modeling techniques allow for deciphering the influence of individual variables on biochar, employing various supervised learning models tailored to different biochar types. Computational chemistry provides knowledge on factors that control phosphorus binding, e.g., the type of phosphorus compound, soil constituents, mineral surfaces, binding motifs, water, solution pH, and redox potential. Phosphorus release from biochar is controlled by coexisting anions, pH, adsorbent dosage, initial phosphorus concentration, and temperature. Pyrolysis temperatures below 600 °C enhance functional group retention, while temperatures below 450 °C increase plant-available phosphorus. Lower pH values promote phosphorus release, while higher pH values hinder it. Physical modifications, such as increasing surface area and pore volume, can maximize the adsorption capacity of phosphorus-loaded biochar. Furthermore, the type of organic acid affects phosphorus release, with low molecular weight organic acids being advantageous for soil utilization. Lastly, biochar-based fertilizers release nutrients 2–4 times slower than conventional fertilizers.
相似文献Microplastic pollution is becoming a major issue for human health due to the recent discovery of microplastics in most ecosystems. Here, we review the sources, formation, occurrence, toxicity and remediation methods of microplastics. We distinguish ocean-based and land-based sources of microplastics. Microplastics have been found in biological samples such as faeces, sputum, saliva, blood and placenta. Cancer, intestinal, pulmonary, cardiovascular, infectious and inflammatory diseases are induced or mediated by microplastics. Microplastic exposure during pregnancy and maternal period is also discussed. Remediation methods include coagulation, membrane bioreactors, sand filtration, adsorption, photocatalytic degradation, electrocoagulation and magnetic separation. Control strategies comprise reducing plastic usage, behavioural change, and using biodegradable plastics. Global plastic production has risen dramatically over the past 70 years to reach 359 million tonnes. China is the world's top producer, contributing 17.5% to global production, while Turkey generates the most plastic waste in the Mediterranean region, at 144 tonnes per day. Microplastics comprise 75% of marine waste, with land-based sources responsible for 80–90% of pollution, while ocean-based sources account for only 10–20%. Microplastics induce toxic effects on humans and animals, such as cytotoxicity, immune response, oxidative stress, barrier attributes, and genotoxicity, even at minimal dosages of 10 μg/mL. Ingestion of microplastics by marine animals results in alterations in gastrointestinal tract physiology, immune system depression, oxidative stress, cytotoxicity, differential gene expression, and growth inhibition. Furthermore, bioaccumulation of microplastics in the tissues of aquatic organisms can have adverse effects on the aquatic ecosystem, with potential transmission of microplastics to humans and birds. Changing individual behaviours and governmental actions, such as implementing bans, taxes, or pricing on plastic carrier bags, has significantly reduced plastic consumption to 8–85% in various countries worldwide. The microplastic minimisation approach follows an upside-down pyramid, starting with prevention, followed by reducing, reusing, recycling, recovering, and ending with disposal as the least preferable option.
相似文献Burning fossil fuels account for over 75% of global greenhouse gas emissions and over 90% of carbon dioxide emissions, calling for alternative fuels such as hydrogen. Since the hydrogen demand could reach 120 million tons in 2024, efficient and large-scale production methods are required. Here we review electrocatalytic water splitting with a focus on reaction mechanisms, transition metal catalysts, and optimization strategies. We discuss mechanisms of water decomposition and hydrogen evolution. Transition metal catalysts include alloys, sulfides, carbides, nitrides, phosphides, selenides, oxides, hydroxides, and metal-organic frameworks. The reaction can be optimized by modifying the nanostructure or the electronic structure. We observe that transition metal-based electrocatalysts are excellent catalysts due to their abundant sources, low cost, and controllable electronic structures. Concerning optimization, fluorine anion doping at 1 mol/L potassium hydroxide yields an overpotential of 38 mV at a current density of 10 mA/cm2. The electrocatalytic efficiency can also be enhanced by adding metal atoms to the nickel sulfide framework.
相似文献This work was focused on evaluating the suitability of replacing Portland cement (PC) by 5, 10 and 15 mass % of activated alum sludge waste (AAS) as a pozzolanic material. Exploitation of low-cost nanocomposite for bolstering the physical, mechanical, and stability against firing of PC–AAS-hardened composites was inspected. CuFe2O4 spinel nanoparticle with average particle size (~ 50 nm) was prepared. Inclusion of CuFe2O4 spinel in different PC–AAS-hardened composites bolsters their physicomechanical features at almost normal curing ages as well as their stability against firing. The positive impact of synthesized CuFe2O4 spinel was affirmed via TGA/DTG and XRD techniques, which indicated the presence of diverse hydration yields such as CSHs, CASHs, CFSH, and CuSH that enhance the overall physicomechanical characteristics and thermal stability of various PC–AAS-hardened composites. The composite containing (90 PC–10 AAS waste–2 CuFe2O4) offers many benefits from the economic and environmental view.
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