Related Emissions Research Articles

Role of sustainable management policy and carbon neutral processes in improving sustainable performance: Study of China's aluminium sector

Aluminium industry is considered as one of the leading natural resource industries. This industry provides one of the crucial inputs for technological development, including green energy technology which contributes almost 3% to global carbon emissions. This study explores the role of sustainable management policy, one of the significant stressors for carbon neutrality, on sustainable performance of firm in aluminium sector. This study also explores the role of energy related inflation in the association between sustainable management policy and sustainable performance. Further, we argue that sustainable management policy can help improve carbon neutrality of processes, which in turn, improves sustainable performance of firm. The focus of the study is China's aluminium sector. China is the world's leading aluminium producer, with around 59% share in global production in 2022. The data is taken from the aluminium sectors. Data was collected using a close ended questionnaire. We employed component based-SEM in two steps for analysis of modelled relationship. The empirical results highlight an instrumental role of sustainable management in adopting the sustainable performance in aluminium sector. Our results also show that sustainable management policy can reduce the process related carbon emissions, further leading to improve the sustainability of a firm. The empirical results also reveal a negative role of energy related inflation, in the association between sustainable management policy and sustainable development. It hampers the effect of sustainable management policy on sustainable performance.

Fossil Fuel Subsidy Inventories vs. Net Carbon Prices

Price incentives for reducing fossil fuel related carbon emissions are an important component of effective and efficient climate policy. Current incentives stem from a mixture of energy taxes and carbon pricing (incentivizing less emissions) and diverse support measures for fossil fuels (incentivizing more emissions). We develop a net carbon price indicator that complements existing subsidy and carbon pricing indicators. It can be calculated on different aggregation levels and compared across countries. We calculate the different components and our aggregate indicator for the year 2018 and for eight countries including the worlds’ six largest emitters. Our analysis reveals large differences in net carbon prices across countries and across sectors within countries. We argue that the sectoral differences can inform about adequate national policy reforms while the aggregate national indicator can be useful for international negotiations about comparable national efforts.

Temporal variations, sources, and regional transport of carbonaceous species in PM2.5 in a northern China city: the role of domestic heating

Domestic heating is an important source of carbonaceous aerosols in northern China in winter. The seasonal variations, sources, and regional transport of carbonaceous species in PM2.5 in Yuncheng in the winter and summer of 2020–2021 were investigated in this study, with a particular focus on the role of domestic heating. Meanwhile, the pollution characteristics of carbonaceous aerosols in Beijing in winter were also investigated for comparison. The mass concentrations of organic carbon (OC) and elemental carbon (EC) and their contributions to PM2.5 were significantly enhanced during the heating period compared to other sampling periods in Yuncheng, however, no obvious differences were observed before and during the heating periods in Beijing. Source apportionment results showed that the heating related emission (50.9%) was the dominant source of total carbon in Yuncheng in the heating period, while vehicular emission (49.6%) was dominant in summer. Combing the positive matrix factorization (PMF) and potential source contribution function (PSCF) analysis, it was concluded that both local and regional heating activities contributed highly to carbonaceous aerosols in Yuncheng. It would be therefore of great environmental benefits to promote the clean residential heating transition in Yuncheng and other similar cities.Graphical

Exploration of microbial signature and carbon footprints of the Nilgiri Hill Region in the Western Ghats global biodiversity hotspot of India

Land use change (LUC), alters the multifarious biodiversity hotspots directly and indirectly through the loss of soil quality. A comparative study on soil carbon status and soil microbiome in undisturbed natural forest ecosystems with that of other land uses which gradually altered over time can serve as a suitable indicator for understanding LUC impact on carbon cycles. With this aim, the current investigation was initiated to infer the cyclic effects of LUC on the soil carbon status under six major ecosystems viz., cropland (CL), deciduous forest (DF), evergreen forest (EF), forest plantation (FP), scrubland (SL) and tea plantation (TP) of the Nilgiri Hill Region (NHR) (India's first biosphere reserve). The total organic carbon (TOC) and carbon stocks were highest in evergreen forest (10.25 %, 322.06 t ha−1) and they decreased with increasing depth of the soil profile across the pools of varying carbon lability. The proportion of active carbon pools (AP) in total carbon was higher in crop land and tea plantation (57.47 %, 58.38 %), however, in the case of evergreen forest, deciduous forest, forest plantation and scrub land the passive carbon pools (PP) (54.99 %, 61.28 %, 59.43 % and 60.70 %) was higher. We discovered LUC has altered the proportion of soil carbon pools, and the efficiency of soil microbiome and has resulted in higher carbon dioxide (CO2) emissions in tea plantation (71.87 t ha−1) and crop land (82.39 t ha−1). However, the native ecosystems (evergreen forest and deciduous forest) with higher recalcitrant carbon pools (46.96 g kg−1 and 34.89 g kg−1) prevent such carbon degradation and thereby hinder the soil carbon emissions as recorded in evergreen forest (48.43 t ha−1) and deciduous forest (56.47 t ha−1). Conclusively, our study demonstrates that LUC has substantially influenced the carbon cycle by altering the carbon stocks and CO2 emissions in relation to soil microbes. Henceforth, in order to maintain carbon footprints and attain carbon net neutrality under the current climate change scenario, suitable carbon management measures must be implemented in carbon-degraded ecosystems (crop land and tea plantation) of NHR.

Surface Activated Pyrolytic Carbon Black: A Dual Functional Sustainable Filler for Natural Rubber Composites.

The significant rise in end-of-life tires (ELTs) globally poses immediate environmental and human health risks. Therefore, to promote ELTs recycling and to reduce tire industry carbon emissions, herein we present a facile approach for fine-tuning the interfacial interactions between pyrolytic carbon black (P-CB) obtained from ELTs and natural rubber (NR) matrix using phosphonium-based ionic liquid (PIL). The reinforcing effect of PIL-activated P-CB was studied by replacing the furnace-grade carbon black (N330-CB) with varying PIL and P-CB loadings. Adding PIL improved the filler dispersion and the cross-linking kinetics with a substantially reduced zinc oxide (ZnO) loading. Considering the cross-linking and viscoelastic properties, it was concluded that the composite, P-CB/N330-CB-PIL (1.5)+ZnO (1) with half substitution of N330-CB with P-CB synergistically works with 1.5 phr PIL and 1 phr of ZnO resulting in improved dynamic-mechanical properties with a minimal loss tangent value at 60 °C (tanδ=0.0689) and improved glass transition temperature (Tg =-38 °C) compared to control composite. The significant drop (~29 % lower) in tanδ could reduce fuel consumption and related CO2 emissions. We envisage that this strategy opens an essential avenue for "Green Tire Technology" towards the substantial pollution abatement from ELTs and reduces the toxic ZnO.

21 Beef Cattle and Global Warming

Abstract Beef cattle production is an important contributor to global warming both nationally and globally. Through a national life cycle assessment, we have determined that the production of beef cattle in the U.S. produces about 243 Tg of carbon dioxide equivalents (CO2e) in global warming with an intensity of 21 kg CO2e/kg of carcass weight. This is about 3.5% of the national inventory of greenhouse gas (GHG) emissions. Globally, the Food and Agriculture Organization (FAO) estimates the direct GHG emissions from all cattle other than dairy and their manure to be about 2,260 Tg or about 4.5% of the total global GHG emission. An important consideration in calculating the contribution of beef cattle is the assumed global warming potentials (GWP) used to relate the warming effect of methane and other compounds to that of CO2. Recommended values have varied over the past 20 years as we learn more about the warming potential of various gases. Values assumed affect published assessments, so it is important to consider the GWP values used when comparing studies. Methane is unique among the major compounds affecting global warming because it has a relatively short life in the atmosphere (half-life of about 8 years). Methane released by cattle and their manure oxidizes in the atmosphere returning the carbon originally fixed by growing plants back to CO2 completing a natural cycle. To better represent the warming effect of methane in the atmosphere, a model called GWP* has been introduced. To use this model, the change in emission rate over time must be quantified. Compared with 50 years ago in the U.S., we are now producing 20% more meat using about 15% fewer cattle. We estimate that the GHG intensity in cattle production has decreased 34%, and the total GHG emission related to beef cattle production has decreased 21% over this period. Considering the change that has occurred, using the GWP* model reduces the global warming impact of U.S. beef cattle by over 50% relative to the use of the commonly accepted current GWP factors. Global change is more difficult to quantify. The FAO estimates that over the past 50 years, the global number of non-dairy cattle has increased about 39% with a 78% increase in meat production and 36% increase in related methane emissions. Applying these data indicates that use of the GWP* model decreases the warming effect of global cattle by about 20%. When making policy decisions to mitigate GHG emissions, it is important to properly represent the relative warming effect of the important greenhouse gases.

Trading activity and market liquidity in tradable mobility credit schemes

The interest in tradable mobility credits (TMC) is growing steadily. Compared to existing instruments, its cap-and-trade design for the demand side ensures that a limited quantity, e.g., traffic and related emissions, can by design not be exceeded. However, most TMC schemes are market-based financial instruments that can only be successful, if the market ensures the most efficient allocation of resources and if one can rely on the price. Hence, TMC schemes require trading activity and a liquid market that only emerges when participants are able and willing to trade. In this paper, we systematically review the TMC literature for aspects of trading activity and market liquidity, summarize the literature streams, and discuss determinants of participants’ ability and willingness to trade TMCs. During the literature review we separate those into demand-side, supply-side, and market regulation factors. This first coherent discussion of creating liquid TMC markets with substantial trading activity challenges the instrument and allows us to draw valuable conceptual implications for the TMC scheme design, but also implications for stakeholders beyond concept. Generating trading activity and liquid markets is thoroughly possible, but robustly achieving it can be challenging.

Seasonal Disparities of Human Health Risk and Particle-Bound Metal Characteristics Associated with Atmospheric Particles in a Fishery Harbor.

The effects of atmospheric pollution from ship emissions have been considered for several harbors worldwide. The health risk assessment and source apportionment of particle-bound metals in a fishery harbor were investigated in this study. The most abundant metal elements in particulate matter (PM) on all sampling days in three seasons were Fe (280.94 ± 136.93 ng/m3), Al (116.40 ± 71.25 ng/m3), and Zn (110.55 ± 26.70 ng/m3). The ratios of V/Ni were 1.44 ± 0.31, 1.48 ± 0.09 and 1.87 ± 0.06 in PM10, PM2.5, and PM1, respectively. Meanwhile, the ratios higher than 1 indicated that fuel oil combustion from ship emission in fishery harbor. The highest deposits of total particle-bound metals in the human respiratory tract were in the head airway (HA), accounting for 76.77 ± 2.29% of the total particle-bound metal concentration, followed by 5.32 ± 0.13% and 2.53 ± 0.15% in the alveolar region (AR) and tracheobronchial (TB) region, respectively. The total cancer risk (CR) of inhalation exposure to local residents exceeded 10-6. Mean total CR values followed the sequence: autumn (1.24 × 10-4) > winter (8.53 × 10-5) > spring (2.77 × 10-6). Source apportionment of related metal emissions was mobile pollution emissions (vehicle/boat) (37.10-48.92%), metal fumes of arc welding exhaust (19.68-34.42%), spray-painting process (12.34-16.24%), combustion emissions (6.32-13.12%), and metal machining processes (9.04-16.31%) in Singda fishing harbor. These results suggest that proper control of heavy metals from each potential source in fishing harbor areas should be carried out to reduce the carcinogenic risk of adverse health effects.

The influence of relative humidity and emission source location on the migration regularity of bioaerosols in a typical urban environment

The influence of relative humidity and emission source location on the migration regularity of bioaerosols in a typical urban environment

From certificate to physics - Paths to net-zero compatible buildings

The role of heat pumps in a decarbonised (thermal) energy system is pivotal. This technology is often in competition with other technologies such as district heating or boilers. When comparing different heating technologies in respect to their CO2 footprint and their costs, the calculation method of future greenhouse gas emission factors of the different energy carriers and energy prices is decisive. Emission factors need to be based on technical and physical fundamentals as (international) green certificates are not a satisfactory proxy for physical emissions, especially for the case of electricity. Currently the Swiss electricity generation system is mostly decarbonised with its high share of hydropower and nuclear energy. However, Switzerland, located in the heart of Europe, has the highest relative shares of cross border capacities, which are relevant for energy trading. In a still fossil dominated European power system, the high volatility of wholesale power prices is entailing a high (temporal) volatility of power related emissions. Thus, the overall carbon footprint of consumed electricity changes significantly over time. Heating demand also shows a dynamic behaviour. It is therefore likely, that a CO2 footprint based on annual averages in heating demand and emission factors could lead to significant errors. The aim of the research was to draw a comparison of the resulting annual CO2 emissions applying different time step aggregation levels (yearly, monthly, typical days) with the results calculated based on a complete year in hourly resolution. The aim was to determine the relative error made through aggregation.

A Low-Cost Wireless Sensor Network for Barn Climate and Emission Monitoring—Intermediate Results

A barn’s climate is vital for animal welfare and emissions control, including greenhouse gases like methane (CH4) and carbon dioxide (CO2) and environmental gases like ammonia (NH3). The goal of this study was to investigate a developed low-cost online tool for monitoring barn climate and air pollutant emissions (OTICE) in naturally ventilated barns. OTICE employed a wireless sensor network with low-cost sensors for gases and climate variables, allowing scalable use across multiple barns. We evaluated the sensors for CO2, NH3, and CH4 for accuracy, both in controlled lab conditions and in a dairy barn in Germany, where measurements were carried out continuously for a duration of 12 days. For the averaged concentration levels over the measurement period, the low-cost sensors agreed well with the reference system, with relative deviations lower than 7% for all three gases, with maximum peak deviations up to 32% for CO2, 67% for NH3, and 65% for CH4, with strong Spearman correlations for CO2 and NH3 (ρCO2 = 0.8, ρNH3 = 0.68) and a rather weak correlation for CH4 with ρCH4 = 0.24. Further calibration and stability investigations are required, especially for CH4 sensing. However, the overall good results for NH3 and especially CO2 measurements indicate a huge potential of the low-cost system as a valuable tool for monitoring relative NH3 emission levels and the measurement of air exchange rates in naturally ventilated barns.

A Life Cycle Assessment to Evaluate the Environmental Benefits of Applying the Circular Economy Model to the Fertiliser Sector

In recent years, the world has witnessed one of the most severe raw material crises ever recorded, with serious repercussions for maintaining its agri-food supply chain. This crisis risks dramatically impacting the poorest areas of the planet and poses profound reflections on global food security. In this complex geopolitical context, the recovery and recycling of renewable resources have become an obligatory path and, today, more than ever, essential in the fertiliser industry. To achieve these objectives, TIMAC AGRO Italia S.p.A. has undertaken a research activity to review the formulation of fertilisers by diversifying the raw materials used and introducing recycled raw materials. This article carried out a life cycle assessment (LCA) on four fertilisers to identify and quantify whether the changes influenced the environmental impacts, highlighting how applying the circular economy within industrial processes can reduce the pressure on natural resources. The results demonstrate that the global warming potential (GWP) impacts of the different reformulated fertilisers show a considerable variation of 4.4–9.2% due to the various raw materials used, the nitrogen content, and related emissions deriving from environmental dispersion. This study shows the importance of the LCA methodology to analyse and quantify the impact categories generated on the life cycle of fertiliser production and to identify the optimal by-products and end-of-waste for the fertiliser industry to find a synergy between environmental and agronomic performance. It also highlights the relevance of the transition to circular production and consumption systems to reduce environmental pressures and their effects on communities and ecosystems without compromising yields. Finally, the positive results encourage accelerating the circular transition and finding alternatives to virgin-mined raw materials.

An Environmental Evaluation of Ventilation Systems Aimed at Reducing Indoor Radon Concentration

The primary measures against radon in buildings are a tight contact structure or venting the subsoil beneath the building. In many cases, ventilation systems used in buildings to ensure good indoor air quality can also be used to reduce the radon concentration. This study aims to evaluate the environmental impacts of residential ventilation systems for their ability to lower the concentration of this gas. The life cycle assessment methodology was used to assess two kinds of ventilation systems. The results indicate that 95% of environmental impacts are associated with operational emissions, while 5% are associated with embodied ones. Moreover, an increase in radon supply rates resulted in an increase in energy consumption and related emissions, for example, the operational energy of an exhaust ventilation system aimed for a reduction to 200 Bq/m3 in a 9/15 cyclic mode range from 9.69 for a radon supply rate of 50 Bq/m3h to 32.27 for 200 Bq/m3h. These simulations show that ventilation systems cannot be considered universally suitable measures to reduce the radon concentration because they may become very energy demanding, and their environmental impact may be significant even considering the type of energy source. Based on this study, we can determine whether it makes sense for a given radon supply rate and energy source to use a ventilation system to reduce the radon concentration in residential buildings.

Time for change: compliance with RCS green theatre checklist-facilitators and barriers on the journey to net zero.

Climate change is an era-defining health concern, with healthcare related emissions paradoxically compounding negative impacts. The NHS produces 5% of the UK's carbon footprint, with operating theatres a recognised carbon hotspot. NHS England aims to become Net Zero by 2045. Consequently, UK Royal Colleges of Surgery have published guidance to foster an evidence-based sustainable transformation in surgical practice. A single-centre quality improvement project was undertaken, aiming to provide an overview of sustainable practice locally. The Intercollegiate "Green Theatre Checklist" was taken as an audit standard, focusing on "preparing for surgery" and "intraoperative equipment" subsections. Any general surgical procedure was eligible for inclusion. Usage of reusable textiles, non-sterile gloves, catheters, antibiotics, alcohol vs. water-based scrub techniques, skin sterilisation choices, and skin closure materials were recorded. Baseline data collection occurred over a 3 week period, followed by dissemination of results locally via clinical governance meetings and poster displays. A re-audit of practice was conducted using the same methodology and duration. Datasets 1 (n = 23) and 2 (n = 23) included open (n = 22), laparoscopic (n = 24), elective (n = 22) and non-elective (n = 24) cases. Good practice was demonstrated in reusable textiles (trolley covers 96%, 78%, drapes 100%, 92%) however procurement issues reduced otherwise good reusable gown use in Dataset 2 in (90%, 46%). No unnecessary catheter use was identified, and loose skin preparations were used unanimously. Uptake of alcohol-based scrubbing techniques was low (15%, 17%) and unnecessary non-sterile glove use was observed in >30% of procedures. All laparoscopic ports and scissors were single use. Carbon footprints were 128.27 kgCO2e and 117.71 kgCO2e in datasets 1 and 2 respectively. This project evidences good practice alongside future local focus areas for improved sustainability. Adoption of hybrid laparoscopic instruments, avoiding unnecessary equipment opening, and standardising reusable materials could reduce carbon and environmental impact considerably. Successful implementation requires considered procurement practices, improved awareness and education, clear leadership, and a sustained cultural shift within the healthcare community. Collaboration among professional institutions and access to supporting evidence is crucial in driving engagement and empowering clinicians to make locally relevant changes a reality.

Game and multi-objective optimization of configurations for multiple distributed energy systems considering building users’ demands and satisfaction degrees

Sustainable building energy supply is crucial to the sustainable development of society, and replacing the separation production energy system with a hybrid renewable energy distributed energy system (DES) can help achieve this goal. However, there are challenges to the application of such building DES, such as collaboration between multiple DESs, conflicts between DESs and users, and user energy management/evaluation. While existing works rarely consider them simultaneously. Therefore, this work presents a two-stage collaborative optimization model to solve these issues. The first-stage optimizes the structures and capacities of DESs and the electricity and heat interchanges between DESs to maximize energy, economic, and emission performances. Based on user energy consumption elasticity, the second-stage evaluates DES revenue and user energy consumption utility/satisfaction to perform a multi-leader and multi-follower game. The interactive game determines energy prices and manages the hourly building user demands. A case study shows the validation of the proposed method. The results indicate that from the initial stage to reaching game equilibrium, the revenue of DESs decreases by approximately 11.2 % due to the declined energy prices, which increase users' hourly loads. Then, users’ utility can be increased by 7.0 % due to satisfaction improvement. Moreover, the renewable energy penetration rate in DESs is increased by 7.1 %, and the relative energy, economic, and emission performances (the baseline is traditional separation production system) of DESs are increased by 5.9 %, 0.5 %, and 4.5 %, respectively. The proposed framework helps to design/manage clean and efficient building energy systems and formulate reasonable energy prices, favoring DES development and carbon neutrality goals.

Agriculture related methane emissions embodied in China's interprovincial trade

Given that agriculture is the predominant source of anthropogenic methane, evaluating the spatio-temporal trends of agriculture related CH4 emissions embodied in trade and the related drivers is an important prerequisite for climate goals. This study first adopted the IPCC tier 2 method to account agriculture related methane emissions, by taking China as a case. The embodied CH4 emissions in the interprovincial trade were then explored by employing multiregional input-output analysis. Socioeconomic factors impacting embodied emissions were uncovered. The results show that the direct CH4 emissions from agriculture in China decreased from 15.50 Tg in 2010 to 12.49 Tg in 2020, mainly contributed by the decrease from livestock production. The direct emissions were dominated by Hunan, Sichuan and Jiangxi broken down by provinces, and rice cultivation and enteric fermentation by process. Total amount of embodied CH4 emissions increased from 11.36 Tg in 2012 to 12.10 Tg in 2015, and decreased to 11.48 Tg in 2017. Shandong had the largest embodied CH4 net inflow, while Heilongjiang had the largest embodied CH4 net outflow. The significant increases in embodied CH4 net outflow of Western China transferred from North were found. GDP per-capita and food production per unit GDP had the most positive and negative contributions to the embodied emissions, respectively. Reliability of the results was further demonstrated by using sensitivity analysis and comparing with similar studies. Finally, implications were raised, including reducing the direct emission intensities, bringing embodied CH4 emission into decision making and setting the interprovincial cooperation mechanisms.

Parametrized passive house standard compliance energy analysis of three exemplary carbon neutral hybrid timber technology-based building renovations in the Republic of Korea

So-called Passive House (PH) and near net Zero Energy Building (nZEB) concepts have become standards for energy-efficient building renovations with low greenhouse gas (GHG) emissions. Minimizing building service energy demand related GHG emissions requires detailed specification and assessment of energy-efficient renovation measures and user behavior prediction. This study examines the compliance with the PH-standard of three exemplary carbon neutral hybrid-timber technology-based building renovations in the Republic of Korea. The simulation of assessment indicators employed a parametric design system to automate exporting data from building models to the PH Planning Package. Calculations were compared with threshold values for the PH-standard to evaluate compliance. The results showed that thermal bridge compensation contributed to the reduction of heating- and cooling-associated primary energy demand. The residential buildings (apartment and multi-unit) achieve the passive house standard, while the renovated mixed-use building does not achieve the standard due to high user and process loads. The parametric design facilitates the evaluation of multiple design options with variable user behavior. Integration of heating, cooling, mechanical ventilation, hot water production, and user behavior related to passive ventilation and the shading of transparent components were found to be critical factors in achieving passive house standard thresholds.

Driving factors of energy related CO2 emissions at a regional level in the residential sector of Iran

Iran has increased its CO2 emissions significantly during the past few decades. The household sector in Iran contributes one of the largest sectors of CO2 emissions. Despite this significant contribution, the existing policies have predominantly concentrated on large-scale initiatives while overlooking the regional role in shaping and implementing these plans. Therefore, this study investigates the relationship between CO2 emissions and the efficient factors in three major groups including energy, climate, and household socio-economic factors. This study aims to address regional carbon emissions and develop CO2 reduction policies tailored to each region's specific circumstances. It focuses on planning strategies at the regional level to effectively tackle CO2 emissions. Household panel data of 28 provinces of Iran are employed by using both static and dynamic panel models for the years 2001 to 2019. Static estimation includes Fixed Effect (FE), Random Effect (RE) and pooled Partial least squares (PLS), Dynamic estimation includes difference Generalized Method of Moments (GMM) and system Generalized Method of Moments (GMM). The empirical result of the static method showed positive dependence of household CO2 emissions on Heating Degree Days (HDD), Cooling Degree Days (CDD), precipitation level, oil consumption, gas consumption, household income, size of household, and also building stocks. In more detail, educational rate, dummy variable (removal of energy subsidy), and oil price reveal the greatest negative impact on the emissions with elasticities of − 0.428, − 0.31, and − 0.15; It represents 1% increase causes − 0.428, − 0.31, − 0.15, decrease CO2 emissions, respectively. however, household size, gas consumption, and oil consumption show the most significant positive effects on CO2 emissions with 1 percent increase causes CO2 emissions increases by 0.1, 0.044, and 0.026, respectively. Regarding the impact of climate factors, a 1% increase in Heating Degree Days, Cooling Degree Days, and precipitation level causes CO2 emissions increase by 0.024%, 0.004%, and 0.011% respectively, due to an increase in fossil energy demand. Results of the dynamic method of the system Generalized Method of Moments are similar to the static estimation results, except for that household size and urbanization are not significant. Also, removing the energy subsidy for fossil fuels due to substantial subsidy in fossil fuels in Iran or implementing a re-pricing energy policy can be a beneficial way to control carbon emissions from households within the provinces of the country. However, it is important to consider that this shift could potentially transfer subsidies to investments in the private sector for renewable energies.

Acoustic emission characteristics of recycled brick-concrete aggregate concrete under freeze-thaw-load coupling action and damage constitutive model

Replacing natural aggregate with construction waste to prepare concrete is an effective way of its resource utilization, which is in line with China 's " carbon peaking and carbon neutrality " strategy and the green development needs of the construction industry. Due to the existing technology is difficult to completely separate waste bricks and waste concrete, this paper mixes recycled brick aggregate and recycled concrete aggregate in a ratio of 1:1 into a mixture, and replaces the natural aggregate with a replacement rate of 30% to prepare Recycled Brick-Concrete Aggregate Concrete (RB-CAC). Concrete in northern China is often subjected to freeze-thaw and load coupling, which accelerates the damage degradation of RB-CAC. Therefore, it is necessary to study its damage constitutive model. In this paper, the effects of different stress levels (0%, 20%, 40%, 60% of flexural strength) and freeze-thaw cycles (0 times, 40 times, 80 times, 120 times, 160 times) on the apparent morphology, mass loss, relative dynamic elastic modulus and acoustic emission characteristics of RB-CAC were analyzed by freeze-thaw-load coupling test, constitutive relation test under uniaxial compression and acoustic emission characteristic test. The dynamic evolution of its frost resistance and damage process was analyzed and evaluated. Finally, combined with the knowledge of damage mechanics, the elastic modulus is defined as the damage variable generated by the freeze-thaw-load coupling effect. Based on the mesoscopic damage theory, the ratio of the number of failure interfaces to the total number of interfaces is defined as the damage variable generated by uniaxial pressure. The damage evolution equation of RB-CAC and the damage constitutive model of freeze-thaw times and stress level are established.

Source function from two-particle correlation through deblurring

In heavy-ion collisions, low relative-velocity two-particle correlations have been a tool for assessing space-time characteristics of particle emission. Those characteristics may be cast in the form of a relative emission source related to the correlation function through the Koonin-Pratt (KP) convolution formula that involves the relative wave-function for the particles in its kernel. In the literature, the source has been most commonly sought by parametrizing it in a Gaussian form and fitting to the correlation function. At times the source was more broadly imaged from the function, still employing a fitting. Here, we propose the use of the Richardson-Lucy (RL) optical deblurring algorithm for deducing the source from a correlation function. The RL algorithm originally follows from probabilistic Bayesian considerations and relies on the intensity distributions for the optical object and its image, as well as the convolution kernel, being positive definite, which is the case for the corresponding quantities of interest within the KP formula.