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As the world No.1 emitter of carbon dioxide (CO2), China has made up its mind to act on climate change. After trials in six pilot regions- Shenzhen, Shanghai, Beijing, Guangdong, Tianjin, Hubei, and Chongqing- a nationwide ETS has been established and implemented in line with the Thirteenth Five-Year Plan period (2016–2020). This paper simulates the effect of a national ETS in China using GTAP 9.1 database and a revised GTAP-E model. The simulation results show that the ETS is very effective in emissions reduction but will cause a mild economic contraction. At the sectoral level, the energy and resource sectors and energy intensive sectors are to be hit hard while most other sectors are affected negatively but insignificantly. [ABSTRACT FROM AUTHOR]

Lime is a product derived from the thermal decomposition of limestone (mainly calcium carbonate, CaCO3) into quicklime (CaO) and carbon dioxide (CO2), also called calcination. Controlled reaction with water is used to manufacture hydrated lime (Ca(OH)2) products. Lime is used in a wide variety of applications: metals industry, construction materials sector, civil engineering, environmental protection, agriculture, and chemical industry. Lime production is one of the sources of anthropogenic CO2 emissions resulting in global warming and ocean acidification. However, a proportion of the CO2 emitted during the calcination is reabsorbed by the lime during the product life within its different applications. This process called carbonation is thermodynamically favoured because it is exothermal. It allows permanent CO2 storage in a stable product since the lime combines with gaseous CO2 reforming CaCO3. This paper reports a comprehensive literature review on the carbonation potential of lime in different applications. The total carbonation potential is assessed as carbonation rate, i.e. the ratio between the CO2 reabsorbed through carbonation during the operational life of lime and the CO2 emitted during limestone calcination. This study provided preliminary evidence that, based on the current EU market, on average 23–33% of lime process emissions are carbonated during the use phase. Carbonation over time is also analysed for the lime applications where information is available. For three applications, namely water, flue gas cleaning and pulp and paper, the carbonation reaction is instantaneous. Up to 22% of the calcination emissions are absorbed within five years based on the current EU market. [ABSTRACT FROM AUTHOR]

As the industrial revolution progresses, carbon dioxide (CO2) and sulfur dioxide (SO2) are major concerns because they are the main contributors to greenhouse gases. The concentration of these harmful gases in the industry is very high, which is emitted by workers and industrial materials. Therefore, it is required to maintain a safe percentage of CO2, SO2, and other harmful gases in the air of industry and ensure safety from fire accidents. This paper presents a compressor driven system that could capture harmful gases including CO2 and SO2 from the polluted air of different industries and households. The captured and separated CO2 works as a fire extinguishing agent to safeguard fire accidents for large industries and households. Thus, this system ensures a protected working place and a healthy atmosphere for industrial workers. Besides, this system can be applied in place of the exhaust gas recirculation (EGR) system in small industries and for a four-wheeler, internal combustion engine, as this system could capture and separate the harmful carbon dioxide and sulfur dioxide. This paper also presents a developed model of different polymeric membranes to simulate the separation of carbon dioxide after the post-combustion process. Computational Fluid Dynamics (CFD) has been performed by COMSOL 5.5 to observe the carbon dioxide separation by polymeric membranes like polycarbonate (0.07 mol/m3) and polytetrafluoroethylene (0.1 mol/m3) polymeric membranes for specific pore sizes which is comparable to experimental data (0.05 mol/m3). [ABSTRACT FROM AUTHOR]

Sweep efficiency of stagnant and poorly drained reservoir zones is extremely relevant task during gas and chemical flooding of hard-to-recover reserves. The paper presents the results of the field implementation of the in-situ CO2 generation technology to recovery of residual oil reserves and increase the sweep efficiency factor. The article presents the results of theoretical and laboratory studies, as well as field cases of an energy- and resource-saving method for oil recovery increase and improving oil production. The results of the reservoir stimulation confirmed the increase in the total incremental oil production after treatment operation on recovering residual oil reserves on. [ABSTRACT FROM AUTHOR]

Reducing greenhouse gas emissions or collecting and converting existing greenhouse gases has become a global concern. One of the most effective methods of utilizing CH4 and CO2 resources is the dry reforming of methane (DRM). Transition metal carbide catalysts have attracted wide attention because of their excellent catalysis performance and carbon deposition resistance. However, pure-phase carbides are easily oxidized and deactivated at atmospheric pressure in DRM reactions. There is a problem of poor dispersion (Mo2C 17 m² /g). Therefore, this paper summarizes the effects of adding active sites and supported carbides on the DRM reaction, discusses the role of active sites and supports in the catalyst, and introduces the different preparation methods of transition metal carbides. This paper also reviews the catalyst mechanism of transition metal carbides in DRM reactions. Nevertheless, the current research in this field needs to be deepened. Therefore, it is necessary to strengthen the exploration of various catalyst preparation methods and mechanisms, so as to realize future improvement in this field. [ABSTRACT FROM AUTHOR]

Negative emissions technologies (NETs) for carbon dioxide removal (CDR) are increasingly important responses to achieve global climate change targets, but to date, there has been insufficient attention to land-based NETs (including afforestation, biochar, and other measures) as an agrarian challenge for the global South. This paper explores the implications of different NETs for land, labor, capital, and politics in rural spaces and contributes to articulating agrarian climate justice by demonstrating the potentially unjust implications of many NETs. The paper concludes with how these measures might be designed to be less negative for rural peoples in future implementation. [ABSTRACT FROM AUTHOR]

This paper examines the environmental Kuznets curve (EKC) hypothesis in Nordic countries (Denmark, Finland, Iceland, Norway and Sweden) over the period 1981–2018. The link between economic growth and carbon dioxide (CO2) emissions is analysed. The study includes causality analysis and controls for cross-sectional dependence (CSD), slope heterogeneity, stationarity and cointegration patterns. Estimations validate the EKC hypothesis for Denmark and Iceland, but not for Norway and Sweden. Finland data show no significantly visible trend. [ABSTRACT FROM AUTHOR]

This paper addresses the impact of political regimes on carbon emissions (CO2) from a historical perspective, covering the period of 1970–2015. Our sample consists of 153 countries that we follow for 20 years before the transition (1970–1990) and 26 years after it (1990–2015). During transition, post-Communist states experienced a decline in CO2, when controlling for economic variables. Transition had a positive impact on the environment only in cases when it was associated with democratization. When transition has led to consolidation of autocratic regimes, CO2 has increased. [ABSTRACT FROM AUTHOR]

The paper reviewed the current perspectives on the development of carbon dioxide (CO2) sequestration through its process conversion into calcite. The process occurs in either geological or biological systems. However, geological sequestration is an expensive process, which is slow in comparison to bio-sequestration. Recently, the bio-sequestration of atmospheric CO2 into the soil using microorganisms such as algae has been investigated. However, the algae cannot be used in the bio-concrete due to their nature as phototrophic organisms. In contrast, bacteria are the most potent organisms in bio-concrete technology. The use of bacterial species in the bio-aerated concrete bricks (B-ACB) and its potential to bio-sequestrate CO2 represents a future strategy to reduce high CO2 pollution. Bacterial cells can capture CO2 by accelerating the carbonation processes, which convert CO2 into calcium carbonate (CaCO3) via carbon anhydrase and urease enzymes. The present paper aimed to highlight and discuss the applicability of bacteria in the B-ACB for capturing and storing CO2. It is evident from the literature that the new trends to use bio-concrete might contribute to the reduction of CO2 by accelerating the carbonation process and strengthening the B-ACB. [ABSTRACT FROM AUTHOR]

Due to the Coronavirus 2019 (COVID-19) pandemic social distance became a necessary strategy adopted in order to curb the fast-rise of infection. However, this strategy adopted by the government has impacted the socio-economic activities and lives of citizens as such new adaptive measures had to be put in place to cope with the pandemic. Accordingly, this study explores the relationship between the current COVID-19 pandemic on hydropower and energy sector in relation to Carbon dioxide (CO2) emission reduction. This paper employs a systematic review of secondary data grounded from document reports and existing literature to explore the trend of COVID-19 pandemic on hydropower and energy sector in relation to CO2 emission reduction. Findings from this article offer empirical evidence toward the impact of COVID-19 on hydropower and energy sector in relation to CO2 emission decrease during the pandemic. More importantly, findings from this study discuss the relationship of COVID-19 on energy sector, impact of COVID-19 on the hydropower sector in comparison to other renewables, impact of COVID-19 and oil demand, and connection of COVID-19 on CO2 emission reduction during the lockdown. Finally, implications are provided to guide policy makers in making decision toward sustainable energy production and CO2 emission reduction. [ABSTRACT FROM AUTHOR]

Taking the Yangtze River Delta (YRD) of China as the research area, this paper studies the influence of freight structure adjustment and energy intensity on carbon dioxide (CO2) emission from the transportation industry. Sample data from 1990 to 2019 are selected, and co-integration analysis is performed using three independent variables: energy intensity, turnover ratio of railway to highway (R/H), and turnover ratio of railway to waterway (R/W). Then, an autoregressive distribution lag-error correction model (ARDL-ECM) is established to estimate the long-run and short-run relationships among the variables through unit root test, autoregressive distributed lag (ARDL) boundary test, and Granger test. The results show that in the long run, the growth of energy intensity leads to the long-term growth of CO2 emission in the transportation sector of the YRD, and R/W and R/H have a suppressive effect on CO2 emission. Granger causality indicates that there is a bidirectional causal relationship between energy intensity and CO2 emission. This work can be a reference for government departments to formulate policies related to carbon emissions in the transportation industry. [ABSTRACT FROM AUTHOR]

Energy generation and pollutant emissions are two faces of the same coin, as the current energy sources i.e., fossil energy, are still considered to be major sources of greenhouse gases (GHG). Therefore, shifting to cleaner energy sources imposes itself as an inevitable solution to reduce this environmental cost. In this paper, a hybrid system based on the multi-agent approach and Long Short-Term Memory (LSTM) neural networks to forecast the energy production and its carbon dioxide (CO2) emissions and simulate the potential emission reduction in case of switching to renewable energy sources is presented. The proposed system's architecture consists of combining LSTM models with the agent-based technology, where multiple LSTM forecasting models were trained to forecast the production of each type of the studied energies and then estimate the equivalent emitted CO2 and calculate the influence of the renewable energy inputs on the carbon emissions and the fossil fuels consumption. The simulation process consists of two phases: firstly, each forecasting agent uses a specific LSTM model to forecast short-term energy production. Secondly, these agents send the forecasted values to the coordination agent who is responsible for calculating the total CO2 emissions and the benefits of the renewable energy inputs. [ABSTRACT FROM AUTHOR]

The experiments on microwave pyrolysis of soybean straw are studied to produce hydrogen-rich gas under CO2 atmosphere in this paper. The microwave power has an important effect on the temperature. The final temperature increases and the time to obtain the highest temperature is shortened with the power increasing. The gas yield, H2 yield and potential H2 yield increase rapidly with the power increasing, and the gaseous yield at CO2 atmosphere is up to 55.70% at 1000 W, and it is higher than N2 atmosphere. The main components of microwave pyrolysis gas product are H2 and CO, the content of syngas (H2+ CO) at CO2 atmosphere is 84.19% at 1000 W, which is more than N2 atmosphere. However, H2/CO ratio is about 0.80 at CO2 atmosphere, which is lower than N2 atmosphere, and H2/CO ratio at CO2 atmosphere is not suitable for the requirements of chemical synthesis. If it is used to synthesize liquid fuels, H2/CO ratio must be adjusted. [ABSTRACT FROM AUTHOR]

Supercritical carbon dioxide fracturing can effectively relieve the environmental pressure caused by in-situ production of oil shale. In order to study the process of fracture propagation during supercritical carbon dioxide fracturing, a fracture propagation model of supercritical carbon dioxide fracturing is established in this paper, and an unsteady temperature field model is introduced. Based on the discrete fracture model, the fluid temperature field in one-dimensional fracture is coupled with the temperature field of two-dimensional reservoir rock. The new model also takes into account the real-time variation of carbon dioxide physical parameters, which are calculated by Span-Wagner and Vesovic equations. Based on this model, the influencing factors of fracture propagation in supercritical carbon dioxide fracturing are analyzed. The results show that the leak-off coefficient has an obvious effect on fracture propagation, so an additive needs to be developed to reduce the leak-off. Since carbon dioxide is a compressible fluid, the reservoir temperature and the original in-situ stress also have a significant impact on the fracture propagation. The temperature of carbon dioxide at the bottom of the well has no significant effect on fracture propagation, because carbon dioxide will quickly reach reservoir temperature when it enters the formation. Comprehensive considering the fracture length, width, filtration, and potential effect on proppant transport during supercritical carbon dioxide fracturing, the injection rate should be as high as possible. [ABSTRACT FROM AUTHOR]

Satellites provide global long-time series of spatio-temporal continuous CO2 observations. However, it is difficult to be applied to the study of small-scale carbon cycle because of its low spatial resolution. In this paper, the Greenhouse Gases Observing SATellite (GOSAT) XCO2 data are super-resolution reconstructed using bicubic interpolation, which improved the spatial resolution from 2.5o to 0.5o. CO2 measurements from ten selected TCCON sites are used to compare with the reconstructed GOSAT. Further, the high accuracy Orbiting Carbon Observatory-2 (OCO-2) data analysed by the combination of geographical grid statistics and kriging is used to evaluate the reconstructed data. The results show that compared with the original GOSAT data, the reconstructed GOSAT data not only improves the spatial resolution but also has little loss of the average accuracy. The mean error of original data has significant seasonal fluctuations with a peak from February to March and a trough from June to July [ABSTRACT FROM AUTHOR]

The CO2-containing natural gas is increasing, and there is an urgent need for green treatment of natural gas containing CO2 to realize the utilization of natural gas. Conventional natural gas decarbonization methods have drawbacks such as non-environmental friendliness, and the low-temperature condensation separation of carbon dioxide (snowing-separation) method as a green method of carbon capture is proposed in this paper. Aiming at the characteristics of CO2 condensation in the snowing-separation process, the growth process of CO2 crystals is obtained by simulation using the CA (Cellular Automata) method and finds that the effect of supersaturation on the growth of CO2 crystals is exponential. The snowing-separation process at .5 MPa is analyzed, and it is found that the condensation range is 158.51 K–173.86 K, the upper limit of CO2 mole fraction in natural gas is 10.1%, and the minimum separation time is 8.65 × 10−8s. Analyzing the influencing factors of CO2 separation efficiency, combining the simulation results with the experimental results, the maximum relative error is 13.93%, which can better predict the snowingseparation technology of CO2 in natural gas, and then promote the development of efficient low-temperature carbon capture process. [ABSTRACT FROM AUTHOR]

Instead, we'd be investing that wood fiber - that biomass - into wood products with a long shelf life, which leads to much bigger carbon emission reductions than what happens when you turn that fiber into wood pellets for bioenergy. Our trees had removed that carbon from the atmosphere and locked it up in the form of wood, but the actual accounting benefits will go to Drax, Britain, because they are the ones who are considered to have I replaced i the burning of fossil fuel with the burning of wood. Biomass, bioenergy, carbon dioxide, climate change, forestry, wood combustion, Drax, sustainable forestry. [Extracted from the article]

The reduction of CO2 into clean energy through electro catalytic technology provides a promising solution to alleviate energy shortages. In this paper, the graphitised material-supported metal dimer used for electro catalytic reduction of CO2 was proposed, and the reduction reaction mechanism was explored by density functional theory. The results indicate that the hydrogenation reduction of CO2 tends to occur preferentially, and it was found that improving the stability of catalyst structure can reduce the free energy of reaction and improve the adsorption effect of reactants, which significantly increase the conversion efficiency of CO2. The activation of CO2 on the catalyst surface is closely related to the binding of O atoms on the metal sites, the main reduction products and their reaction pathways were clarified. The reduction over potentials of CuCo-C, CuRh-C, CuZn-C and ZnCu-C were 0.915, 0.820, 0.774, and 0.354 V, respectively, thus ZnCu-C had a lower reduction over potential and higher catalytic efficiency. [ABSTRACT FROM AUTHOR]

This paper introduces the Fleet Size and Mix Vehicle Routing Problem with Synchronized Visits (FSM-VRPS), an extension of the Vehicle Routing Problem with Synchronization (VRPS), where a mixed fleet composed of electric and conventional bikes, and passenger cars having different acquisition costs are considered. The problem consists of planning a set of different vehicle routes to serve a set of clients who may require more than one visit by different healthcare specialists, and some of these visits should be synchronized. Moreover, each client must be visited within a specified time window. In addition, the problem uses bikes to reduce Carbon Dioxide (CO2) emission for environmentally cleaner routing operations. This problem has many real-life applications, such as the scheduling of visits for homecare givers in the healthcare sector. We present a mixed integer linear-programming formulation and develop a Multi-Start Adaptive Large Neighborhood Search with Threshold Accepting algorithm. The results showed that our algorithm is highly effective on the FSM-VRPS, as well as on the heterogeneous VRPS. We also demonstrate the advantage of adopting different types of vehicles in terms of reducing the number of vehicles and costs. The analysis of the results also indicated that the new components added to the standard Adaptive Large Neighborhood Search algorithm enhanced intensification and diversification mechanisms during the search process. [ABSTRACT FROM AUTHOR]

Ventilation plays an important role in mitigating the risk of airborne virus transmission in university classrooms. During the early phase of the COVID-19 pandemic, methods to assess classrooms for ventilation adequacy were needed. The aim of this paper was to compare the adequacy of classroom ventilation determined through an easily accessible, simple, quantitative measure of air changes per hour (ACH) to that determined through qualitative "expert judgment" and recommendations from the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), and the American Conference of Governmental Industrial Hygienists (ACGIH)®. Two experts, ventilation engineers from facilities maintenance, qualitatively ranked buildings with classrooms on campus with regard to having "acceptable classroom ventilation." Twelve lecture classrooms were selected for further testing, including a mix of perceived adequate/inadequate ventilation. Total air change per hour (ACH) was measured to quantitatively assess ventilation through the decay of carbon dioxide in the front and rear of these classrooms. The outdoor ACH was calculated by multiplying the total ACH by the outdoor air fraction. The classrooms in a building designed to the highest ASHRAE standards (62.1 2004) did not meet ACGIH COVID-19 recommendations. Four of the classrooms met the ASHRAE criteria. However, a classroom that was anticipated to fail based on expert knowledge met the ASHRAE and ACGIH criteria. Only two classrooms passed stringent ACGIH recommendations (outdoor ACH > 6). None of the classrooms that passed ACGIH criteria were originally expected to pass. There was no significant difference in ACH measured in the front and back of classrooms, suggesting that all classrooms were well mixed with no dead zones. From these results, schools should assess classroom ventilation considering a combination of classroom design criteria, expert knowledge, and ACH measurements. [ABSTRACT FROM AUTHOR]

The impact on the use of carbon dioxide (CO2) as a diluent in the fuel and oxidizer streams on the formation and evolution of precursor nanoparticles and soot in axisymmetric ethylene laminar coflow diffusion flames is experimentally explored using optical diagnostics in this paper. The optical diagnostics employed are based on temporally and spectrally resolved point measurements of laser-induced fluorescence, elastic scattering, and laser-induced incandescence. The measurements provide insight to indicative structure and concentration of precursor nanoparticles, and enable the determination of volume fraction and mean diameter of soot. Previous studies have indicated that the use of CO2 as a diluent compared to nitrogen can reduce soot formation through both chemical and thermal effects. However, the effect of CO2 addition on precursor nanoparticles' concentrations and structure is not well understood, hence exploring the impact of CO2 on precursor nanoparticles is one of the primary aims of this study. Flames with CO2 as a diluent in the jet only, coflow only, and both streams are identified and investigated. For the flames studied with respect to the replacement of N2 with CO2: i), the soot volume fraction and mean soot diameter is reduced, and ii) precursor nanoparticles concentration is reduced, and the structural transformation is delayed. [ABSTRACT FROM AUTHOR]

Rotary drying is one of the most common unit operations in industries. It is a complex nonlinear process, and it is difficult to control with conventional methods. In this paper, a fuzzy multivariable controller is designed for an industrial rotary drying system. This fuzzy controller is applied to a fertilizer production unit to save energy and improve its performance. Based on the dryer operating conditions, the proposed control system aims to keep the exhaust gas temperature at the dryer outlet as close as possible to the optimum value. Thus, a reduction in energy consumption is achieved without losing the quality of the final product. Practical aspects of the industrial reality, such as the plant lacking an online moisture measurement instrument, are considered. The results prove that the proposed fuzzy control is able to reduce biomass consumption by 9%, which represents an annual reduction of 648 tons of carbon dioxide (CO2) emissions to the atmosphere. [ABSTRACT FROM AUTHOR]

In recent years, China's air quality problem is very serious. Among them, carbon dioxide emissions have been high, which has caused a series of ecological and environmental problems. In order to deeply study the relevant problems, this paper selects the information priority damping gray model to study and predict the carbon emissions of thirty-one provinces and municipalities in China. The model can give priority to new information and adjust the prediction trend, the accuracy of the model is verified by several cases. Through the data collection and data analysis of relevant provinces and cities, it is concluded that a total of twenty-one provinces and municipalities can reach the carbon peak in 2030, of which the carbon dioxide emission of Beijing is expected to drop to 51.3774 million tons by 2030. Ten provinces will not be able to reach the carbon peak by 2030. Among them, by 2030 the carbon dioxide emission of Jiangsu Province is expected to increase to 84.4668 million tons, but the growth rate is declining. The research results can be used as a reference for relevant departments. [ABSTRACT FROM AUTHOR]

For a smart grid system operating with clustered generating units, the challenge usually lies in the optimal scheduling of energy resources. Thus, the improvement of a unit commitment problem gains importance in the present power network. In this paper, a novel probability algorithm is proposed for solving the unit commitment problem, in which five separate units from a four-cluster group are operated for one day. This is done with the aim of optimizing the characteristics such as optional units, generation, operating, and marginal cost. Being a multi-objective function, the other factors such as cost response, unit commitment of supply clustering units, clustering of combined operational units, and CO2 emissions are also included. For this study, an RLC load is mathematically modeled in the cluster system, whereas the Unit Control is provided by a Converter and Battery Management Unit. The clustering model developed along with the Unit demand aims to increase the optional units (from 20 to 100 units), decrease the average demand (from 99 to 93 percentage), and lower the generating and marginal costs (from Rs.23,881 to Rs.21,079, Rs.43,082 to Rs.42,111, Rs.71,162 to Rs.64,955, Rs.83,169 to Rs.81,694, Rs.104,104 to Rs.102,928). The suggested algorithm is simulated for a comprehensive smart grid system and the response for marginal cost, CO2 emissions are obtained. In comparison to conventional schemes, the results of the proposed optimization approach show a reduction in the Carbon dioxide emission (in the range of 100 to 400 kg) and in the losses after adding working units with cluster spans of 0.5 to 1.5 kW. [ABSTRACT FROM AUTHOR]

To reach the short-term targets of the carbon dioxide limit, measures such as carbon capture and storage are necessary. The objective of this paper is to assess some low-temperature post-combustion technologies for the capture of CO2 from combustion gases. Two methods for the liquefaction and separation of CO2 are discussed: The use of the low-temperature exergy of liquefied natural gas (LNG), while regasifying the LNG, and a refrigeration cycle with helium as the working fluid. Each of these methods is evaluated at three CO2 concentrations: 30%, 13%, and 4%. The results showed that an increase in the concentration of CO2 in the combustion gases causes a large increase in the overall exergetic efficiency and a large decrease in the cost of CO2 capture and energy penalty of the capture process. In addition, these advantages can be seen when the liquefaction method is changed from helium refrigeration cycle to LNG regasification. For a 30% CO2 concentration using LNG, the overall exergetic efficiency is 41.2%, and the cost of CO2 capture is 45.5 $/tCO2 with a CO2 capture rate of 96.3%. [ABSTRACT FROM AUTHOR]

In the face of mounting global climatic pressures, negative emission technologies (NETs) for carbon dioxide removal (CDR) are increasingly proposed as necessary for meeting climate targets. While initial work has identified the potential of terrestrial NETs, a diverse set of marine/ocean-based NETs are gaining new and particular attention. Emerging studies on the feasibility of marine NETs are urgently needed, especially to explore the logics that public groups use to judge different approaches, and to ensure that design and governance of these technologies align with public values and priorities. This study explores factors of interest in understanding public views on four marine NETs, both perceptions of climate severity and urgency, and beliefs about marine environments. It uses a quantitative survey to explore how a representative sample of people in British Columbia, Canada and Washington state, United States evaluate four marine NETs: coastal restoration; ocean alkalinity enhancement; ocean fertilization; and offshore direct air carbon capture and storage. We find that perceived severity and urgency of climate change predicts greater comfort with all NETs studied, and views of marine environments as adaptable, fragile and manageable vary in predicting both greater and lesser comfort. Drawing upon these insights, the paper offers reflections on the conditional thinking linked with emerging views of marine NETs, concluding with methodological suggestions for future research on public perceptions as concerns the deployment of ocean-based CDR near and long term. Incorporating these insights into policy for ocean-based CDR will be important to ensuring responsible governance of these technologies. Key policy insights Incorporating research on public perceptions will be important to the design of marine NETs and accompanying policies. Public groups in both British Columbia and Washington expressed high levels of comfort with coastal restoration, some comfort with offshore direct air carbon capture and storage, and some discomfort with ocean alkalinity enhancement and ocean fertilization. Perceived severity and urgency of climate change predicted greater comfort with all approaches; this evidence aligns with a small but growing body of scholarship indicating openness to environmental intervention amongst public groups concerned with climate impacts. Beliefs about marine environments, namely whether they are 'adaptable', 'manageable' or 'fragile', also predicted comfort, suggesting that CDR in ocean contexts requires further examination regarding public perceptions. [ABSTRACT FROM AUTHOR]

Post-harvest loss of agriproducts is a major issue of concern not only for the farmers but also for the distributors, sellers, and consumers as it significantly affects the economic aspects associated with the large-scale agriproduct industry. This loss is mainly due to the attack of various pathogens, and contact with various chemicals or gases present in the atmosphere such as oxygen, carbon dioxide, water, etc. leading to a loss of visual appeal, nutritional content, and quality along with a reduction in the shelf life of products. The use of nanotechnology has provided innovative solutions to this problem with the application of nanomaterials such as nanoparticles, nanocomposites, and nano-films in coating, packaging, and diagnostics. This paper highlights the role of nanotechnology to enhance the shelf life, visual appeal, and nutritional value of agriproducts by protecting them from the harmful environment and other agents. In this regard, the in-vivo and in-vitro studies conducted for the antimicrobial potential of nanoparticles have been explored for various pathogens. The use of nano-coatings and nanosensors in active packaging has been discussed. Biodegradable packaging, the need of the hour in the context of environmental issues has also been explored. [ABSTRACT FROM AUTHOR]

China's numerous resource-based cities have confronted severe environmental and economic problems, which were substantial impediments to the regional sustainable development. In 2013, China started to implement its 'National Sustainable Development Plan of Resource-Based Cities', in order to transform the previous development patterns. This study employs the difference-in-differences (DID) method to evaluate the policy's impact on the city-level carbon dioxide (CO2) emission intensity. CO2 intensity is defined as the scale of CO2 emitted per unit of GDP. The research sample covers 326 Chinese cities during 2008—2017. Research results indicate that the policy significantly increased the CO2 intensity in resource-based cities. Moreover, it is found that the policy dampened resource-based cities' innovation levels and these cities did not strengthen their environmental regulations, which can be provided as the explanations of why the policy effect on carbon intensity was positive. Furthermore, this study reports the discrepancies in policy effects when cities have different development stages, spatial locations and marketization levels. Overall, this research discovers an undesirable policy effect. More actions should be taken to reduce the carbon intensity during the structural transformation in resource-based cities. [ABSTRACT FROM AUTHOR]

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Exposure to air can cause amine solutions in CANada Deuterium Uranium (CANDU) reactor secondary coolant circuit feed tanks to absorb carbon dioxide (CO2). Likewise, carbon dioxide can be absorbed directly into the amine-containing secondary coolant by air ingress during shutdown, lay-up, and startup. Sampling operations, including transferring the sample to the laboratory and subsequent analyses, can also provide opportunities for CO2 contamination. This paper reports the results of laboratory and chemical modeling studies to examine the effects of CO2 contamination on aqueous morpholine solutions. The chemistry of CO2 uptake by feed tanks containing up to 50 wt% (11.5 mol·kg-1) morpholine at 25°C was modeled using the OLI Studio 9.5.2 chemical equilibrium model, and the speciation was confirmed by 13C nuclear magnetic resonance spectroscopy (NMR) measurements. The effects of CO2 contamination on the pH of the secondary coolant containing 60 ppm (0.006 wt%, 7.00 × 10-4 mol·kg-1) morpholine and the resulting effects on the solubility of magnetite and nickel oxide from 25°C and 250°C at steam saturation were modeled as a function of CO2 loading using the Electrical Power Research Institute chemical modeling software MULTEQ v.8. The chemical modeling calculations show that concentrated alkaline morpholine solutions at room temperature and pressure would be expected to have a strong tendency to absorb CO2 and have additional uptake abilities due to the formation of morpholine carbamates. For dilute morpholine solutions at room temperature and pressure, the solutions are still sufficiently alkaline to absorb enough CO2 to cause a measurable change in the pH of the secondary coolant. This effect was shown to be negligible under reactor operating conditions. The absorption of CO2 would potentially have the most effect on either unprotected feed tanks or during lay-up conditions in the steam generators, as it could depress the pH of the lay-up solution and adversely affect the rate of corrosion in the internal components of the steam generators (e.g., carbon steel materials). The 13C NMR measurements on samples of 50 wt% aqueous morpholine solutions from feed tanks at the Ontario Power Generation's Pickering Nuclear Generating Station found that CO2 was below the 0.02 wt% detection limit, and suggest that the procedures used to avoid CO2 contamination in feed tanks are effective. The 13C NMR was shown to be an effective tool for monitoring CO2 uptake by morpholine solution in the feed tanks under conditions in which they may have undergone abnormal exposure to air. [ABSTRACT FROM AUTHOR]

This study investigates two configurations of novel solar energy-assisted combined cooling, heating and power (CCHP) systems suitable for the dairy industry. The system uses carbon dioxide (CO2) as the working fluid. The cooling and heating outputs were used for the simultaneous chilling and pasteurization of milk. The electrical power produced in the turbine is used to run the compressor and cater to the miscellaneous electrical demands of the dairy farm, thereby achieving grid independence. A detailed thermodynamic analysis was performed on the two configurations (with and without reheating) to identify the impact of various independent parameters on system performance. In addition, an irreversibility analysis was performed on the components in both configurations to obtain an idea of the losses occurring in the system. It is observed that the addition of the reheater provides a better specific net power output by approximately 4% over a variation of 6000 kPa in the cycle maximum pressure. [ABSTRACT FROM AUTHOR]

The diffusion of molecules on interstellar grain surfaces is one of the most important driving forces for the molecular complexity in the interstellar medium. Due to the lack of laboratory measurements, astrochemical modeling of grain surface processes usually assumes a constant ratio between the diffusion energy barrier and the desorption energy. This over-simplification inevitably causes large uncertainty in model predictions. We present a new measurement of the diffusion of CO $ _2 $ 2 molecules on the surface of non-porous amorphous solid water (np-ASW), an analog of the ice mantle that covers cosmic dust grains. A small coverage of CO $ _2 $ 2 was deposited onto an np-ASW surface at 40 K, the subsequent warming of the ice activated the diffusion of CO $ _2 $ 2 molecules, and a transition from isolated CO $ _2 $ 2 to CO $ _2 $ 2 clusters was seen in the infrared spectra. To obtain the diffusion energy barrier and pre-exponential factor simultaneously, a set of isothermal experiments were carried out. The values for the diffusion energy barrier and pre-exponential factor were found to be $ 1300\pm 110 $ 1300 ± 110 K and $ 10^{7.6\pm 0.8} $ 10 7.6 ± 0.8 s $ ^{-1} $ − 1 . A comparison with prior laboratory measurements on diffusion is discussed. [ABSTRACT FROM AUTHOR]

This study provides scientific evidence for the process of denim biodegradation and the viability of including denim waste in large scale composting facility feedstock streams. Fourteen samples of denim using different dyes and dye processes provided by Cotton Incorporated as well as worn and unworn whole and scrap denim fabric were incorporated into a manure/bedding and food scrap windrow at the Cornell composting facility and in a bench scale laboratory trial. Grab samples of compost were analyzed for compost parameters, metals and PFAS. Visual observation of decomposition of denim showed polyester blended denim degraded at a slower rate than non-blended denim. However, after four months of hot composting, most of the denim had decomposed into organic matter, leaving only small pieces of the polyester thread, labels, and pockets. Bench scale degradation, tracked by carbon dioxide evolution and mass difference showed significant degradation at the macro and microscopic levels at day 75. Composting denim fabric has no detrimental effect on the composting process, nor on the quality of the resulting compost and thus can be used to grow cotton and other crops, reducing the carbon footprint, and contributing to the circular economy. [ABSTRACT FROM AUTHOR]

The main goal of this research was to evaluate the capability of chitosan (CS)-lightweight expanded clay aggregate (Leca) composite as a green adsorbent for efficient capture of carbon dioxide (CO2). The adsorption process was modelled by response surface methodology (RSM). The composite was recognised by BET, SEM, EDX, XRF, XRD, TGA, XPS and FTIR analysis. It was evidenced the CS-Leca properties attributing to its adsorption ability were eminently improved as compared to pristine Leca. Maximum removal efficiency of CO2 (91.59%) was achieved at 40°C, 40 mL/min gas flow rate and 5% moisture content. Under aforementioned provisions, the actual CO2 removal percentage was found to be 90.4%. According to uptake isotherm studies, the Toth model indicated good affinity between the sorbent and sorbate. This model declares adsorption of CO2 onto CS-Leca involves a heterogeneous and uneven adsorption behaviour. The monolayer adsorption capacity (qm) was determined to be 351.24 mg/g. The outcomes of thermodynamic studies displayed that the adsorption was physical and exothermic in nature. The exothermic isosteric heat of adsorption (IHA) was found as 37.1–48.3 kJ/mol which represented weak chemical interactions between CS-Leca and CO2 molecules. Adsorption mechanism studies revealed that multiple mechanisms are involved in the adsorption reaction of CO2. Regeneration tests of CS-Leca exhibited multiple potential applications. All these results enlightened that the CS-Leca, due to its grafting polymer, can be applied as a potential sorbent to the recycle of CO2 and other acidic gases. [ABSTRACT FROM AUTHOR]

Carbonic anhydrases (CAs) are a zinc metalloenzymes that catalyse the reversible hydration of carbon dioxide to bicarbonate and proton, pivotal for a wide range of biological processes. CAs are involved in numerous pathologies and thus represent valuable drug targets in the treatments of several diseases such as glaucoma, obesity, tumour, neuropathic pain, cerebral ischaemia, or as antiinfectives. In the last two decades, several efforts have been made to achieve selective CA inhibitors (CAIs) employing different drug design approaches. However, N-substitutions on primary sulphonamide groups still remain poorly investigated. Here, we reported for the first time the co-crystallisation of a N-nitro sulphonamide derivative with human (h) CA II pointing out the binding site and mode of inhibition of this class of CAIs. The thorough comprehension of the ligand/target interaction might be valuable for a further CAI optimisation for achieving new potent and selective derivatives. [ABSTRACT FROM AUTHOR]

Urease is a kind of nickel-dependent metalloenzyme, which exists in the biological world widely, and can catalyse the hydrolysis of urea into ammonia and carbon dioxide to provide a nitrogen source for organisms. Urease has important uses in agriculture and medicine because it can catalyse the production of ammonia. Therefore, in this review, metal-based inhibitors of urease will be summarised according to different transition metal ions. Including the urease inhibition, structure–activity relationship, and molecular docking. Importantly, among these reviewed effective urease inhibitors, most of copper metal complexes exhibited stronger urease inhibition with IC50 values ranging from 0.46 μM to 41.1 μM. Significantly, the collected comprehensive information looks forward to providing rational guidance and effective strategies for the development of novel, potent, and safe metal-based urease inhibitors, which are better for practical applications in the future. [ABSTRACT FROM AUTHOR]

Acute respiratory failure (ARF) is a common clinical critical syndrome with substantial mortality. Extracorporeal carbon dioxide removal (ECCO2R) has been proposed for the treatment of ARF. However, whether ECCO2R could provide a survival advantage for patients with ARF is still controversial. Electronic databases (PubMed, Embase, Web of Science, and the Cochrane database) were searched from inception to 30 April 2022. Randomized controlled trials (RCTs) and observational studies that examined the following outcomes were included: mortality, length of hospital and ICU stay, intubation and tracheotomy rate, mechanical ventilation days, ventilator-free days (VFDs), respiratory parameters, and reported adverse events. Four RCTs and five observational studies including 1173 participants with ARF due to COPD or ARDS were included in this meta-analysis. Pooled analyses of related studies showed no significant difference in overall mortality between ECCO2R and control group, neither in RCTs targeted ARDS or acute hypoxic respiratory failure patients (RR 1.05, 95% CI 0.83 to 1.32, p = 0.70, I2 =0.0%), nor in studies targeted patients with ARF secondary to COPD (RR 0.80, 95% CI 0.58 to 1.11, p = 0.19, I2 =0.0%). A shorter duration of ICU stay in the ECCO2R group was only obtained in observational studies (WMD −4.25, p < 0.01), and ECCO2R was associated with a longer length of hospital stay (p = 0.02). ECCO2R was associated with lower intubation rate (p < 0.01) and tracheotomy rate (p = 0.01), and shorter mechanical ventilation days (p < 0.01) in comparison to control group in ARF patients with COPD. In addition, an improvement in pH (p = 0.01), PaO2 (p = 0.01), respiratory rate (p < 0.01), and PaCO2 (p = 0.04) was also observed in patients with COPD exacerbations by ECCO2R therapy. However, the ECCO2R-related complication rate was high in six of the included studies. Our findings from both RCTs and observational studies did not confirm a significant beneficial effect of ECCO2R therapy on mortality. A shorter length of ICU stay in the ECCO2R group was only obtained in observational studies, and ECCO2R was associated with a longer length of hospital stay. ECCO2R was associated with lower intubation rate and tracheotomy rate, and shorter mechanical ventilation days in ARF patients with COPD. And an improvement in pH, PaO2, respiratory rate and PaCO2 was observed in the ECCO2R group. However, outcomes largely relied on data from observational studies targeted patients with ARF secondary to COPD, thus further larger high-quality RCTs are desirable to strengthen the evidence on the efficacy and benefits of ECCO2R for patients with ARF. ECCO2R therapy did not confirm a significant beneficial effect on mortality. ECCO2R was associated with lower intubation and tracheotomy rate, and shorter mechanical ventilation days in patients with ARF secondary to COPD. An improvement in pH, PaO2, respiratory rate, and PaCO2 was observed in ECCO2R group in patients with COPD exacerbations. Evidence for the future application of ECCO2R therapy for patients with ARF. The protocol of this meta-analysis was registered on PROSPERO (CRD42022295174). [ABSTRACT FROM AUTHOR]

The warming impact of methane (CH4) emissions calculated using the metrics proposed by the Intergovernmental Panel on Climate Change (IPCC), which measure its global warming potential in 100 years (GWP100) expressed as carbon dioxide equivalents (CO2e), accounts for the greatest impact in animal production chains. This work uses the new metrics, proposed to consider the difference between short living climate pollutants (SLCP), such as CH4, and long living climate pollutants (LLCP), such as carbon dioxide (CO2), which measure the warming equivalent (we) effect relative to that of CO2 in a given time frame (GWP*) and expressed as CO2we. The GWP* was applied to CH4 emissions from all Italian livestock supply chains and compared with GWP100 for annual and cumulative assessment from 2010 to 2020 of the impact of this gas on climate change. Using official data published by Istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA) from 1990 to 2020, almost all species, except for buffalo (+272.6% of emissions calculated with the new metrics), revealed lower CH4 emissions with the greatest re-dimensioning for non-dairy cattle (-53786 kt of CO2we of calculated with GWP* compared to +66437 kt of CO2e estimated with the GWP100 method). The total cumulative contribution of Italian livestock production to global warming over the past 10 years, including the nitrous oxide (N2O) emissions, has been greatly negative (-48759 kt of CO2we) compared to the data calculated using the GWP100 method (+206091 kt of CO2e). In conclusion, the application of GWP* metric to CH4 emissions of all Italian livestock supply chains allowed to better identify the role of Italian livestock on climate change. Over the 2010–2020 time frame, the Italian animal supply chains reduced the warming impact related to its CH4 emission, with the ruminants (expect buffaloes) being the major contributor to this positive effect. The application of GWP* metric reduced the warming impact of CH4 emissions of Italian dairy cattle, non-dairy cattle, sheep, goats, poultry and rabbits. The reduction of CH4 emission from the major ruminant species is the major contributor to the positive effect on climate change detected over 2010–2020 time frame. The application of GWP* metric to CH4 emissions of all Italian livestock supply chains allowed to better identify the role of Italian livestock on climate change. [ABSTRACT FROM AUTHOR]

The EU, UK, US, and other nations consider wood to be a carbon neutral fuel, ignoring the carbon dioxide emitted from wood combustion in their greenhouse gas accounting. Many countries subsidize wood energy – often by burning wood pellets in place of coal for electric power – to meet their renewable energy targets. But can wood bioenergy help cut greenhouse emissions in time to limit the worst damage from climate change? The argument in favor seems obvious: wood, a renewable resource, must be better than burning fossil fuels. But wood emits more carbon dioxide per kilowatt-hour than coal – and far more than other fossil fuels. Therefore, the first impact of wood bioenergy is to increase the carbon dioxide in the atmosphere, worsening climate change. Forest regrowth might eventually remove that extra carbon dioxide from the atmosphere, but regrowth is uncertain and takes time – decades to a century or more, depending on forest composition and climatic zone – time we do not have to cut emissions enough to avoid the worst harms from climate change. More effective ways to cut greenhouse gas emissions are already available and affordable now, allowing forests to continue to serve as carbon sinks and moderate climate change. [ABSTRACT FROM AUTHOR]

Compared with the production of ordinary Portland cement (OPC) with large carbon emissions, biological carbon sequestration to prepare low-carbon cement can effectively decrease carbon dioxide (CO2) emissions, which can reduce the greenhouse effect, thereby reducing the frequency and intensity of climate disasters. Carbon-capturing bacteria (CCB) can capture atmospheric CO2 and convert it into bicarbonate ions, which can be combined with calcium ions to form CaCO3 cement that can partially replace OPC for dust control. This study compared the ability of two CCBs (Paenibacillus mucilaginosus and Streptomyces microflavus) to capture CO2. The biomineralization efficiency of CaCO3 for P. mucilaginosus (39.34%) was much higher than that for S. microflavus (7.38%) in a Ca(NO3)2 solution in the concrete-curing room environment. The decomposition temperature of the CaCO3 crystals in DI was slightly higher than that of P. mucilaginosus and significantly higher than that of S. microflavus. When the spraying time was equal to three, 10% carbide sludge (CS) content was optimal according to the surface hardness (HD) of the consolidation layer of the sand samples. The CaCO3 mineralized by CCBs can be used to consolidate desert sand and dust in practical engineering applications. [ABSTRACT FROM AUTHOR]

Waste tires are also known as "black pollution", and pose significant risks to human health and ecosystems. The pyrolysis process can recover valuable products such as natural gas, oil, and pyrolysis carbon black (CBp), with CBp being the most important one. However, CBp from waste tires has a high degree of particle aggregation and low oil absorption value, making it difficult to further utilize. In this work, we propose a novel method to activate CBp by simulated fuel gas, which fully utilizes exhaust gas resources and enables the reuse of resources. The simulated fuel gas, composed of a mixture of N2 and CO2, was used to investigate the effects of activation temperature (700–1000 °C), activation time (2–5 h), flow rates (30–50 mL·min−1), and the content of CO2 in the simulated fuel gas (10%-90% (volume)) on increasing the specific surface area. The samples were analyzed using XRD, SEM, N2 adsorption/desorption, and Raman shift. The results indicate that the hybrid atoms and carbon atoms in CBp can absorb enough energy to open the closed pores, allowing the activator to fully react with CBp. This work demonstrates a feasible approach to improve the high value-added utilization of cracked carbon black. [ABSTRACT FROM AUTHOR]

This work aims to assess whether there is a convergence in the emission of Greenhouse Gases (GHG) in the states of Brazil. To achieve this objective, the Phillips and Sul (2007) time series methodology was employed, testing the hypothesis of global (or common) convergence, using data from the Greenhouse Gas Emissions and Removal Estimation System (Sistema de Estimativas de Emissões e Remoções de Gases do Efeito Estufa - SEEG), for the period of 1989–2018, which provides the emission, in tons, of Carbon Monoxide (CO) in agriculture and livestock, as well as of Carbon Dioxide (CO2), for changes in land and forest use. Among the main results, the formation of different convergence clubs is suggested, rejecting the hypothesis of global convergence, and thus presenting four convergence clubs for the CO pollutant and three clubs for the CO2, with two divergent states. When analysing the convergence clubs, it was found that there was a significant reduction in CO emissions in all clubs, and while analysing the CO2, only two of the clubs, which were clubs 3 and 4, managed to reduce their emissions. [ABSTRACT FROM AUTHOR]

Sulfur-containing ABA-type polycarbonate triblock copolymers were synthesized via sequential copolymerization of propylene oxide (PO) and carbon dioxide (CO2), followed by propylene oxide (PO) and phthalic thioanhydride (PTA) in the presence of water and Salen-Metal catalysts. The reaction was catalyzed using Salen-Co(III)-Cl/[PPN]Cl and Salen-Cr(III)-Cl/[PPN]Cl catalyst systems. The content of thioester units in the copolymer chain could be adjusted by varying the feed ratios of PTA. These triblock polymers displayed a higher refractive index, reaching up to 1.561. [ABSTRACT FROM AUTHOR]

Natural zeolite is among the low-cost materials that can be used to remove contaminants in biogas. The cleaning of biogas increases its energy density and reduces possible negative effects. The current study aimed to upgrade biogas using natural zeolites. The activation of natural zeolite was done using sodium hydroxide. The adsorbent samples were characterised using an XRF machine, while the biogas samples were analysed using Shimadzu gas chromatography and a portable digital gas detector. The effect of zeolite-to-water ratio on the carbonation process was investigated. In addition, the effects of biogas flow rate, adsorbent dose and contact time on the dry adsorption process were studied. The maximum CO2 uptake of zeolite was 4.8 and 0.2 mmol/g by dry adsorption and wet carbonation process, respectively. The results indicate that surface adsorption favoured by a low Si2O3/Al2O3 ratio was more prominent than carbonation that requires high basic oxides. The results showed that an increase in the dose of activated clay from 2.5 to 35 g increased the removal efficiency of CO2 from 11.2% to 79.8%, while the CO2 uptake decreased from 4.8 to 2.5 mmol/g. Furthermore, the experimental data fitted best to pseudo-first-order kinetics and the Bohart-Adams model for the breakthrough curve. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) can reduce cognitive abilities at higher concentrations. CO2 can be used as a proxy for gas transport in an indoor environment and as an index to determine Indoor Air Quality (IAQ). In the present work, CO2 transport inside a real university classroom has been analysed experimentally and numerically. The main novelty is related to the experimental characterization of the airflow, boundary conditions for swirl diffusers and CO2 transport occurring in an actual university classroom equipped with a Turbulent Mixing Airflow (TMA) system. The numerical methodology, validated against the experimental measurements performed by the authors, has been used to identify the most suitable turbulence model for both thermo-fluid dynamic and CO2 transport simulations. Three different RANS k-ε turbulence models have been compared: the Standard k-ε, the RNG k-ε and the Realizable k-ε. Moreover, the evacuation time and the effects of turbulent diffusivity have been analysed. [ABSTRACT FROM AUTHOR]

The ability to accurately estimate and identify the hotspots (top influencing factors) of freight embodied carbon dioxide (CO2) emissions is essential for introducing efficient control strategies. However, most existing studies ignore the life cycle and secondary activities of CO2 emissions in freight transportation. This research gap hinders policy makers from having a more complete understanding of hotspots, which should be focused upon to efficiently reduce CO2 emissions. Hence, a generalized framework for the complete estimation and hotspot identification of freight embodied CO2 emissions is constructed. This framework is also applicable to different regions and countries. Then, the proposed framework is applied to the Yiwu-Ningbo case, and the results indicate that: (1) the studied road transportation chain generates 9.25% higher embodied CO2 emissions than the studied rail transportation chain when transporting one container, indicating the small marginal influence of modal shift measures in terms of reducing embodied CO2 emissions. (2) Supply-side hotspots, especially the direct CO2 emissions of road transportation, should be focused upon, in order to effectively reduce embodied CO2 emissions. (3) To effectively reduce the embodied CO2 emissions of a freight corridor, the effectiveness and implementability of reduction measures should be considered in a balanced manner. [ABSTRACT FROM AUTHOR]

For inland cities with high concentration of carbon dioxide in the air, the seismic performance of RC structures deteriorates over time. In this study, a previously developed concrete carbonation and corrosion model was introduced to the framework of seismic fragility analysis to investigate the effects of environmental factors on the seismic performance of RC structures, considering carbon dioxide, humidity, and temperature. An approach to quantify the effects of these environmental effects on the time-dependent fragility of deteriorated RC buildings in the inland atmosphere environment was proposed. A four-story three-bay RC structure was analysed as a case study. Pushover analysis was performed to identify the damage limits of the structure as a function of the exposure time (0, 25, 50, 75 and 100 years). Fragility curves of the structure at different exposure times were developed based on the time-dependent seismic demands and predefined limit states. The results show that the structure deteriorates when exceeding the design life of durability. In general, the damage to the deteriorated structure increases with time and intensity of ground motions. In particular, the margin between severe damage and collapse decreases significantly over time. This means that aging structures are likely to collapse suddenly after severe damage occurs. Therefore, the time-dependent seismic performance of the aging structures in the inland cities should be carefully considered. [ABSTRACT FROM AUTHOR]

Lithium orthosilicate (Li4SiO4) has the highest carbon dioxide (CO2) absorption capacity among the other lithium-based ceramic materials and is also suitable for high-temperature application for CO2 absorption. In this work, lithium orthosilicate pebbles of 1.0 mm size with 20% excess lithium carbonate were synthesized and fabricated by using Solid State Reaction Process (SSRP) and experiments were carried out to study the effect of various process parameters on its adsorption capacity of CO2 from air-CO2 mixture at elevated temperatures. The various process parameters studied were: operating gas flow rate, bed wall temperature and CO2 concentration in air on which very limited works have been reported. Effects of operating temperature, flow rate and inlet concentration of CO2 on absorption capacity have been studied to develop break through curves. The cyclic tests have been carried out with 15% CO2 concentration in air at 400°C and 200 LPH flowrate using the same material and carried out 135 consecutive absorption-desorption experimental runs. It was found that the CO2-absorption capacity of Li4SiO4 pebbles at 400°C and 200 LPH flowrates is about 31% for 30% carbon dioxide concentration in air and 22% for 15% carbon dioxide concentration in air. Moreover, no reduction in CO2-absorption capacity of the material was observed even after 135 consecutive absorption-desorption cycles. [ABSTRACT FROM AUTHOR]

The localized forced ignition and subsequent flame propagation have been analyzed for stoichiometric biogas-air mixtures ( C H 4 / C O 2 / a i r blend) with different spatial distributions (uniform, Gaussian and bimodal) and mean levels of C O 2 dilution (i.e. mole fraction of C O 2 ) for different flow conditions (e.g. quiescent laminar condition and different turbulence intensities) using three-dimensional Direct Numerical Simulations. A two-step chemical mechanism with sufficient accuracy is used to capture the effects of C O 2 dilution on the laminar burning velocity of the b i o g a s − a i r m i x t u r e . A parametric analysis in terms of the mean, standard deviation and integral length scale of the initial Gaussian and bimodal distributions of spatial C O 2 dilution in the unburned gas has been conducted. Qualitatively similar behavior has been observed for all three initial spatial distributions of C O 2 . A departure from uniform conditions was found to increase the range of reaction rate magnitudes of C H 4 , which impacts the burned gas volume and, in turn, increases the variability of the outcomes of the ignition event (successful thermal runaway and subsequent self-sustained propagation or misfire). Turbulence intensity and the mean level of dilution were found to have significant impacts on the outcome of the localized forced ignition, and an increase of either quantity acts to reduce the burned gas volume irrespective of mixture composition due to the enhancement of heat transfer from the hot gas kernel, and the heat sink effects of C O 2 , respectively. An increase of the integral length scale l ψ for the spatial distribution of C O 2 dilution increased the probability of a successful outcome of the ignition event. A uniform initial spatial distribution was found to be optimal, and in the case of a departure from non-uniform conditions, larger variability in the outcome are obtained for a Gaussian initial distribution of C O 2 dilution than a bimodal one. The variance of the C O 2 dilution distribution has been found to have a negligible impact on the outcomes observed, as it was dominated by the effects arising from turbulence intensity, nature of initial C O 2 distribution and integral length scale of C O 2 dilution. [ABSTRACT FROM AUTHOR]

The injected fluid can chemically react with reservoir rocks and fluids, which changes the properties of petroleum and rocks. Consequently, oil recovery rates are subject to change during the EOR process. Therefore, the study of chemical reactions during EOR process is important. During the CO2 injection, the deposition of asphaltene, and the change of minerals, dissolution and deposition can occur at the same time. Dissolution of rock minerals can increase permeability and effective porosity, but precipitation of asphalt and deposition of these minerals can have the opposite effect. This study investigates the CO2 flooding process in heavy oil reservoirs containing highly permeable sandstone and assesses the effect of orientation on oil recovery and rock-fluid interactions. The results show that due to the gravitational stability in the vertical configuration, there is more oil recovery, mineral solution, and asphaltene sedimentation in the vertical configuration compared to the horizontal configuration. The percentage of asphaltene in the sandpacket model was 1.92 weight percent vertically and 1.18 weight percent horizontally. The increase in porosity for vertical was 2.6% and 1.1% for horizontal infusion. From this it can be concluded that the dissolution of minerals is higher with vertical injection than with horizontal injection. [ABSTRACT FROM AUTHOR]