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1.
根据C_3植物和C_4植物对高浓度CO_2的不同反应,评述了富CO_2大气对生态系统的影响。结论是大气CO_2浓度增加将导致生态系统发生一系列变化,包括生物多样世的减少、营养循环受阻、虫灾发生和温室效应加剧等。  相似文献   

2.
ZrO2负载过渡金属氧化物催化剂对CO+NO(O2)反应的影响   总被引:6,自引:0,他引:6  
王月娟  周仁贤 《环境化学》1999,18(5):432-436
本文运用固定床微反技术考察了Cu,Fe,Mn,Cr,Co和Ni负载(ZrO2载体)氧化物对CO+NO(O2)反应的催化活性。研究了NO和CO在不同比例时,催化剂对N2O和N2生成的影响。结果表明,在NO+CO反应中,NO和CO的比例对催化剂活性和N2O,N2生成均有明显的影响,CuOx/ZrO2催化剂的活性最高;N2O是NO+CO反应的中间产物,低温或NO过量时有利于生成N2O,高温或NO不足时有  相似文献   

3.
O(^1D)与CF2ClBr的反应研究   总被引:3,自引:0,他引:3  
于勇  潘循皙 《环境化学》1999,18(5):414-421
本文研究了CF2ClBr-O3体系在253.7nm紫外光照下所引发的O(^1D)与CF2ClBr的反应。O(^1D)与CF2ClBr反应的最终产物为CF2O,Cl2,B2r;实验中得到O(^1D)与CF2ClBr的反应速率常数为1.01×10^-10cm^3·molecule^-1·s^-1,并且对O(^3P)与CF2LlBr的反应可能性以及O(^1D)与CF2ClBr的反应机理进行了讨论。  相似文献   

4.
过渡金属催化剂上CO还原NO反应性能的研究   总被引:3,自引:0,他引:3  
罗孟飞  朱波 《环境化学》1996,15(4):296-300
在一系列负载型过渡金属催化剂上考察了CO-NO和CO-O2的反应性能。结果表明,催化剂的CO-O2反应活性高于CO-NO反应,催化剂表面NO解离是CO-NO反应的速率控制步骤。低温反庆有利于N2O的生成,高温有利于N2的生成。  相似文献   

5.
黄君礼  程丽华 《环境化学》1999,18(4):373-379
本文对以稳定剂H2O2和Na2CO3与ClO2制备的所谓“稳定性二氧化氯”溶液的UV吸收光谱、纸层析特性、微观结构及离子色谱进行了分析,并与纯NaClO3及ClO2溶液做了对比。  相似文献   

6.
三株分别属于光合细菌三个主要类群(紫无硫细菌、紫硫细菌和绿硫细菌)的菌种和两种产甲烷细菌进行了混合培养试验,结果表明,自养生长的光合细菌减少了产甲烷菌有CH4生成,而异养生长时紫无硫细菌Rhodopseulomous palustris能利用乙酸放出CO2供产甲烷菌利用。在光照厌氧条件下,三株光合细菌的生长培养物和静止细胞都能利用有机酸产氢,有时还伴随着CO2产出。同时试验了不同pH值、温度和光照  相似文献   

7.
黄君礼  程丽华 《环境化学》1999,18(4):366-372
本文并以稳定剂H2O2和Na2CO3与ClO2制备的所谓“稳定性二氧化氯”溶液中ClO2存在型体及碳酸盐存在型进行了分析。  相似文献   

8.
二氧化氯对水中酚类化合物的去除效果   总被引:11,自引:0,他引:11  
黄君礼  李春兰 《环境化学》1998,17(2):174-179
本文采用模拟水厂混凝沉淀-过滤处理工艺,进行了ClO2投量和投加点对水中酚类化合物的去除效果试验研究,并与液氯做了对比,结果表明,ClO2对酚类化合物的去除效果优于液氯,且后投ClO2的效果好于中间投和预投ClO2,双层滤料过滤好于单层滤料,这为ClO2在饮用水中的应用提供了科学依据。  相似文献   

9.
氧化热处理对活性炭纤维吸附转化SO2能力的影响   总被引:5,自引:0,他引:5  
李开喜  凌立成 《环境化学》1999,18(3):210-215
本文研究了经O2,空气或HNO3氧化后,高温下热处理改性的活性炭纤维(ACF)在O2和水蒸气存在下脱除SO2的能力。结果表明,氧化热处理改性后,ACF的脱硫能力都有明显提高,其中O2改性的ACF脱硫活性最高,HNO3改性的ACF最低,空气改性的ACF居中。并对改性ACF具有不同脱硫活性的原因进行了分析。TPD实验表明,H2SO4从O2改性ACF上脱除最容易。  相似文献   

10.
H2O2对抗旱性不同玉米品种愈伤组织抗氧化系统的影响   总被引:1,自引:0,他引:1  
两个玉米品种愈伤组织经10-4molL-1、10-3molL-1和10-2molL-1H2O2处理3h后,电解质泄漏率加大;H2O2和MDA含量增加;AsA和CAR含量的减少.10-4molL-1的H2O2处理对愈伤组织产生的氧化伤害较小.抗旱性较强品种PAN6043愈伤组织的抗氧化酶(SOD、POD、AP和GR)活性高于抗旱性较弱品种SC701,AsA和CAR含量的下降程度低于SC701.PAN6043愈伤组织具有较强的抗H2O2能力,与含高活力抗氧化系统密切相关  相似文献   

11.
In 2017 the paper ‘The Sustainable Development Oxymoron: Quantifying and Modelling the Incompatibility of Sustainable Development Goals’ was published, showing that there is a conflict between socio-economic development goals and ecological sustainability goals using cross-country time-series data. The authors looked at production-based CO2 emissions to measure and model the 13th SDG goal addressing climate change. Their models showed that production-based CO2 emissions were stalling or even decreasing in rich countries, which suggests that other countries are also likely to see stalling and decrease in their CO2 emissions once they become rich. However, this conclusion can be challenged when accounting for consumption-based CO2 emissions rather than production-based CO2 emissions. In this follow-up paper, we re-run some of the analyses performed in the original paper making use of consumption-based CO2 emissions. The analysis confirms the inherent SDG conflict between socio-economic and ecological SDGs. But, this new analysis demonstrates that from a consumption perspective the trend of stalling or decreasing CO2 emissions is reversed, with natural depletion costs being exported to poorer countries. Despite this new perspective on CO2 emissions, the conflict between SDG goals can still be avoided by making investments in public health, education and renewable energy, as suggested in the original paper.  相似文献   

12.
中国能源消费导致的CO2排放量的差异特征分析   总被引:6,自引:0,他引:6  
主春杰  马忠玉  王灿  刘子刚 《生态环境》2006,15(5):1029-1034
运用一种不产生残差的方法——对数平均迪氏指数法LMDI(logarithmicmeanDivisiaindex),对中国部分省份、区域能源消费导致的二氧化碳排放量进行了分解分析。将二氧化碳排放总量的变化分解成五个主要影响因素,即化石燃料的排放系数、能源消费结构、能源强度、人均GDP和人口总数。研究表明我国各省(地区)的二氧化碳排放量在1996年后呈现零(或负)增长趋势,主要影响因素是能源强度的提高;各省(地区)的二氧化碳排放量地区差异显著。因此,要在全国实现二氧化碳排放量的总体减排,应从提高能源利用效率,调整产业结构,消除地区发展的不平衡,逐步改善能源消费结构等方面考虑。  相似文献   

13.
This paper examines long-run and short-run dynamics of renewable energy consumption on carbon dioxide (CO2) emissions and economic growth in the European Union. This study employs cointegration tests, Granger causality tests and vector error correction estimates to examine the direction of Granger causality, the long-run dynamics of economic growth and energy variables on carbon emissions. This study analyses time series data from the World Development Indicators over the period from1961 to 2012. The results of this study support a link between renewable energy consumption, economic growth, industrialization, exports and CO2 emissions in the long-run and short-run. The results support that the sign of the long-run dynamics from the endogenous variables to the CO2 emissions variable is negative and significant, which implies that the energy and environmental policies of the European Union aimed at curbing CO2 emissions must have been effective in the long-term. Furthermore, renewable energy consumption and exports have significant negative impact on CO2 emissions in the short-run. However, industrialization and economic growth have positive impact on CO2 emissions in the short-run. The results suggest that both economic growth and industrialization must have been achieved at the cost of harming the environment. The finding suggests that the increasing consumption of renewable energy tends to play an important role in curbing carbon emissions in the region.  相似文献   

14.
In a parsimonious two-sector general equilibrium model, we challenge the widely-held tenet that within a cap-and-trade system renewable energy policies have no effect on carbon emissions. If the cap does not capture all sectors, we demonstrate that variations of a renewable energy subsidy change aggregate carbon emissions through an inter-industry leakage effect. We decompose this effect into intuitively intelligible components that depend in natural ways on measurable elasticity parameters. Raising the subsidy always reduces emissions if funded by a lump-sum tax, reinforcing recent findings that tightening environmental regulation can cause negative leakage. However, if the subsidy is funded by a levy on electricity, it can increase emissions. These results provide a valuable basis for an informed design of renewable energy policies and an accurate assessment of their effectiveness. We highlight how a state-of-the-art statistic used by governments to gauge such effectiveness, “virtual emission reductions”, is biased, because inter-industrial leakage effects are not captured.  相似文献   

15.
Background, aim and scope During the last years, climate change mitigation has become the most important issue in environmental policy. Objectives of achieving a 20?% use of renewable energies by 2020 are set up. In Germany, the highest share in renewable energies is biomass. Because of the increasing relevance of bioenergy, the German advisory council on the environment (SRU) worked on a special report in 2007 (SRU 2007). This article summarises the main features of this report. Main features The biomass potential in Germany is discussed as well as the impact of biomass use on the natural environment and its potential in saving greenhouse gas emissions. Furthermore, the actual political strategy on biomass utilisation in Germany is reported. Results While the energetic use of biogenic waste is mostly reasonable, the energetic use of raw materials is in direct competition with the use of food or products. This leads to an increasing demand and thus to increasing impacts on the natural environment. Moreover, there is not enough arable land available for the cultivation of energy crops to achieve political targets. The ambitious targets thus promote the import of biomass and biogenic energy carriers, especially from non-European countries. The various biomass utilisation pathways have different potentials on saving greenhouse gas emissions. While biofuels appear to have a low potential, the highest greenhouse gas savings can be achieved by decreasing the generation of electricity plus heat. Discussion and conclusions The production of biogenic raw materials and biogenic waste is not sustainable in itself. Political targets are to be challenged, particularly concerning the international perspective. Regarding climate change mitigation, the priority of the targets must be discussed, in particular with regard to biofuels. Recommendations and perspectives Due to the ambitious targets, the optimal way in mitigating climate change as well as a framework for the environmentally friendly cultivation of energy crops should be the key tasks of the political strategy. Biomass should not be considered isolated from other energy sources. From the long-term perspective, a cross-sectoral emission-trading scheme should be realised.  相似文献   

16.
The ability to store excess intermittent renewable electricity is increasingly being seen as a key option for integrating large quantities of renewable capacity. However, intermittent energy sources currently account for very small amounts of total generation. Despite this fact, policymakers have begun implementing requirements that will dramatically increase the amount of bulk storage capacity. This paper examines the social benefits provided by bulk storage in the Texas electricity market, which has a large amount of renewable capacity relative to other states, but still quite limited renewable penetration. We focus on the impact of arbitraging electricity across time—a major service of bulk storage. Using current storage technologies, we demonstrate that electricity arbitrage will increase daily CO2 emissions by an average of 0.19 tons for each MWh stored. In addition, daily SO2 emissions will increase by an average of 1.89 pounds/MWh while NOX emissions will fall by an average of 0.15 pounds/MWh.  相似文献   

17.

Energy derived from fossil fuels contributes significantly to global climate change, accounting for more than 75% of global greenhouse gas emissions and approximately 90% of all carbon dioxide emissions. Alternative energy from renewable sources must be utilized to decarbonize the energy sector. However, the adverse effects of climate change, such as increasing temperatures, extreme winds, rising sea levels, and decreased precipitation, may impact renewable energies. Here we review renewable energies with a focus on costs, the impact of climate on renewable energies, the impact of renewable energies on the environment, economy, and on decarbonization in different countries. We focus on solar, wind, biomass, hydropower, and geothermal energy. We observe that the price of solar photovoltaic energy has declined from $0.417 in 2010 to $0.048/kilowatt-hour in 2021. Similarly, prices have declined by 68% for onshore wind, 60% for offshore wind, 68% for concentrated solar power, and 14% for biomass energy. Wind energy and hydropower production could decrease by as much as 40% in some regions due to climate change, whereas solar energy appears the least impacted energy source. Climate change can also modify biomass productivity, growth, chemical composition, and soil microbial communities. Hydroelectric power plants are the most damaging to the environment; and solar photovoltaics must be carefully installed to reduce their impact. Wind turbines and biomass power plants have a minimal environmental impact; therefore, they should be implemented extensively. Renewable energy sources could decarbonize 90% of the electricity industry by 2050, drastically reducing carbon emissions, and contributing to climate change mitigation. By establishing the zero carbon emission decarbonization concept, the future of renewable energy is promising, with the potential to replace fossil fuel-derived energy and limit global temperature rise to 1.5 °C by 2050.

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18.
• Mitigating energy utilization and carbon emission is urgent for wastewater treatment. • MPEC integrates both solar energy storage and wastewater organics removal. • Energy self-sustaining MPEC allows to mitigate the fossil carbon emission. • MPEC is able to convert CO2 into storable carbon fuel using renewable energy. • MPEC would inspire photoelectrochemistry by employing a novel oxidation reaction. Current wastewater treatment (WWT) is energy-intensive and leads to vast CO2 emissions. Chinese pledge of “double carbon” target encourages a paradigm shift from fossil fuels use to renewable energy harvesting during WWT. In this context, hybrid microbial photoelectrochemical (MPEC) system integrating microbial electrochemical WWT with artificial photosynthesis (APS) emerges as a promising approach to tackle water-energy-carbon challenges simultaneously. Herein, we emphasized the significance to implement energy recovery during WWT for achieving the carbon neutrality goal. Then, we elucidated the working principle of MPEC and its advantages compared with conventional APS, and discussed its potential in fulfilling energy self-sustaining WWT, carbon capture and solar fuel production. Finally, we provided a strategy to judge the carbon profit by analysis of energy and carbon fluxes in a MPEC using several common organics in wastewater. Overall, MPEC provides an alternative of WWT approach to assist carbon-neutral goal, and simultaneously achieves solar harvesting, conversion and storage.  相似文献   

19.
Chu  Mingna  Li  Yang  Cui  Kai  Jian  Jiahuang  Lu  Songtao  Gao  Peng  Wu  Xiaohong 《Environmental Chemistry Letters》2022,20(2):999-1007
Environmental Chemistry Letters - Carbon dioxide (CO2) emissions and rising fossil fuel consumption have already resulted in global warming and energy crisis. Therefore, conversion of CO2 into...  相似文献   

20.
● Methanol effectively reduces CO, HC, CO2, PM, and PN emissions of gasoline vehicles. ● Elemental composition of methanol directly affects the reduction of emissions. ● Several physicochemical properties of methanol help reduce vehicle emissions. The transport sector is a significant energy consumer and a major contributor to urban air pollution. At present, the substitution of cleaner fuel is one feasible way to deal with the growing energy demand and environmental pollution. Methanol has been recognized as a good alternative to gasoline due to its good combustion performance. In the past decades, many studies have investigated exhaust emissions using methanol-gasoline blends. However, the conclusions derived from different studies vary significantly, and the explanations for the effects of methanol blending on exhaust emissions are also inconsistent. This review summarizes the characteristics of CO, HC, NOx, CO2, and particulate emissions from methanol-gasoline blended fuels and pure methanol fuel. CO, HC, CO2, particle mass (PM), and particle number (PN) emissions decrease when methanol-blended fuel is used in place of gasoline fuel. NOx emission either decreases or increases depending on the test conditions, i.e., methanol content. Furthermore, this review synthesizes the mechanisms by which methanol-blended fuel influences pollutant emissions. This review provides insight into the pollutant emissions from methanol-blended fuel, which will aid policymakers in making energy strategy decisions that take urban air pollution, climate change, and energy security into account.  相似文献   

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