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It is also found that the mixing of CF4 makes insulating mixtures depend more linearly on the proportions of buffer gas than CO2 and N2.As a widely used insulating medium, sulfur hexafluoride (SF6) is a greenhouse gas with very high global warming potential (GWP).
The global warming potential of CH4 is known to be 23 times more than that of carbon dioxide, resulting in it being a significant role player in the greenhouse gas family.
As HFC-134a is a potent greenhouse gas, this increasing concentration has implications for climate change.
Traces of C2H6 with microbial CH4 and a range of C and H isotopic compositions of CH4 indicate gases of different origins are mixing in sub-surface pathways; gas mixtures are present in groundwater.
Thus CO 2 , a greenhouse gas, is contributing to global warming and should be reduced.
Theoretically, combustion or gasification of biomass could provide more CO2 for greenhouse enrichment than propane or natural gas per unit of energy.
The high yield of C2H6 formed from the low-temperature tunneling reaction suggests the occurrence of efficient conversion of C2H4 into C2H6 on the cold dust grains.
Open accessJournal ArticleDOI
01 Jan 2016
5 Citations
The experimental results showed implement of SF 6 /N 2 mixed gas with 30% SF 6 supersedespure SF 6 gas, could effectively reduce the consume of SF 6 , and remit greenhouse efect.
The greenhouse with CO2 supplied from bottles turns out to be superior to tthe greenhouse with CO2 supplied by burning gas.
Journal ArticleDOI
28 Feb 1997-Science
35 Citations
(p. 1288) suggesting that C2H6 may be produced by high-pressure chemical reactions deep within the planet.

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What are the short-term and long-term effects of acid rain on the quality and availability of freshwater resources?
5 answers
To produce heat with biomass what is the conversion efficiency?
5 answers
The conversion efficiency of biomass into heat varies depending on the method used. Biomass gasification can achieve efficiencies of up to 86%, while a biomass gasifier system demonstrated an efficiency of 75% with a gas heating value of 6MJ/Nm^3. Additionally, a biomass energy conversion device utilizing biological fermentation units and combustion heat exchange units ensures high microorganism organic fermentation efficiency and high biomass energy utilization rates. Furthermore, a method involving a catalytic cracking device in a petroleum processing process allows for efficient biomass conversion into high-quality fuel oil, eliminating the need for a separate biomass pyrolysis device and reducing production costs. Overall, various technologies and systems exist to convert biomass into heat with notable efficiency levels.
How do acid rains form ?
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Acid rain forms primarily due to the emission of sulfur dioxide (SO2) and nitrogen oxide (NOx) from various human activities like industrial processes, vehicle emissions, and power plants. These pollutants react with water vapor in the atmosphere to create sulfuric acid (H2SO4) and nitric acid (HNO3), resulting in acidic precipitation in the form of rain, fog, or snow. The acidity of acid rain is typically between pH 4.2 and 4.4, significantly lower than the normal rain pH of 5.6. Acid rain poses severe environmental risks, impacting ecosystems, aquatic environments, soil, vegetation, buildings, and human health. To mitigate the effects of acid rain, reducing sulfur dioxide and nitrogen oxide emissions, transitioning to renewable energy sources, conserving energy, and following regulations are crucial steps.
How to compare heavy metals in leachated from a soil column study?
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To compare heavy metals in leachates from a soil column study, various leaching agents and techniques can be employed. Different studies have investigated the effectiveness of chemical leaching agents like FeCl3, Fe(NO3)3, KCl, KNO3, HCl, citric acid, iron nitrate, and polyepoxysuccinic acid in removing heavy metals such as Cd, Pb, Cu, and Zn from contaminated soil. Additionally, dynamic leaching tests have been conducted to explore the leaching characteristics of Pb and Cd in mining soil, evaluating pollution using Risk Index (RI) and Assessment Code (RAC). The leaching behavior of heavy metals can vary based on factors like pH, leaching solution composition, and particle size, influencing the dissolution and removal efficiency of heavy metals from the soil. By considering these factors and employing suitable leaching agents, the comparison of heavy metals in leachates from a soil column study can be effectively conducted.
What is the average gas yield in biomass gasification in m^3/kg?
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The average gas yield in biomass gasification typically ranges from about 0.60 to 1.87 m^3/kg of biomass consumed. Various studies have reported different gas yields based on different operating conditions and biomass types. For instance, a study on cherry wood gasification in a lab-scale rotary kiln gasifier found hydrogen yields of 2-4% and carbon monoxide varying between 8-21%. In another study using interconnected fluidized beds, a maximum syngas yield of 1.87 m^3/kg was achieved at a gasifier temperature of 820 ℃. Additionally, experiments with a fixed-bed downdraft biomass gasifier showed an average syngas yield of 1.77 Nm3 per kg of wood waste consumed. These findings collectively indicate the variability in gas yields in biomass gasification processes.
What is the average gas yield of gasifier propotypes in m³/kg?
4 answers
The average gas yield of gasifier prototypes ranges from 0.74 m³/kg to 1.87 m³/kg. Specifically, a study on a bubbling fluidized bed reactor achieved a gas yield rate of 0.74 m³/kg, while another study on interconnected fluidized beds reported a maximum syngas yield of 1.87 m³/kg. Additionally, a pilot scale fixed-bed downdraft biomass gasifier experiment showed an average syngas yield of 1.77 m³/kg. These results highlight the variability in gas yield depending on the type of gasifier and operational conditions, emphasizing the importance of optimizing gasification processes for efficient syngas production from biomass.
How does the extreme phenomena afect to the chemical composition of rain water?
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Extreme phenomena such as hurricanes, haze episodes, and sandy dust events significantly impact the chemical composition of rainwater. During hurricanes like Irene, rainwater composition changes with wind direction and speed, containing marine salts initially and transitioning to terrestrial components as the storm progresses. Haze episodes, caused by biomass burning, lead to acidic rainwater with lower sulfate and nitrate deposition rates compared to mineral components. Additionally, sandy dust events affect rainwater chemistry by increasing anions and cations concentrations, with principal compounds like (NH4)2SO4, CaSO4, NaCl, and MgCl2 being prominent. These extreme events alter the pH, ion concentrations, and overall chemical makeup of rainwater, highlighting the diverse sources and processes influencing rainwater quality during such occurrences.
What is the status of air quality in the world?
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Air quality globally remains a significant concern due to its adverse impacts on human health and the environment. Studies show that air pollution is a longstanding threat, with historical records dating back to ancient times, culminating in severe events like the London smog in 1952. In 2019, air pollution was responsible for 7 million premature deaths worldwide, affecting regions like Europe, North America, and East Asia, while also contributing to climate change. Recent data indicates that fine particulate matter (PM 2.5) poses a substantial risk, with over 96% of days exceeding WHO guidelines in 2020, leading to an estimated 4.2 million premature deaths globally. The outbreak of COVID-19 in 2019 prompted industrial shutdowns, resulting in reduced emissions and improved air quality in major cities, showcasing the direct link between human activities and air pollution-related mortality rates.
Can inert gases be used to purge catalysts such as indium oxide?
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Inert gases, such as nitrogen, can indeed be utilized for purging purposes in various applications involving catalysts like indium oxide. For instance, inert gas purge systems are designed to enhance efficiency and throughput by reducing purge times. Additionally, inert gas purge stations are implemented to prevent oxidation on semiconductor materials by filling pods with inert gas, showcasing the protective role of inert gases in sensitive processes. Moreover, inert gases are employed in exposure apparatuses to maintain controlled environments during substrate exposure, highlighting their crucial role in ensuring optimal conditions for catalytic reactions. Overall, the use of inert gases for purging catalysts, including indium oxide, is a common practice in various industrial and semiconductor processes, contributing to improved performance and product quality.
What are the various factors that influence the cost of pyrolisis?
5 answers
Various factors influence the cost of pyrolysis, including equipment capital costs, process design constraints, impregnation of biomass with metal precursors, pyrolysis temperature, and biomass material used. Equipment capital costs play a significant role, while impregnating biomass with metals like iron and nickel can reduce tar content and enhance catalytic effects, affecting overall costs. Additionally, the choice of biomass material, such as wood sawdust or straw, impacts the pyrolysis process and product yields. Labor and capital equipment costs are crucial in determining system viability, with economies of scale playing a key role in improving economic feasibility. Understanding these factors is essential for assessing the economic viability and cost-effectiveness of pyrolysis processes.
What is the construction risk at facade?
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