Increment Of Emissions Research Articles

Evidences of the structures controlling the unrest in Campi Flegrei, Italy; Joint interpretation of ambient noise and local earthquake tomography

Campi Flegrei is one of the largest active calderas exhibiting several episodes of unrest since historical times. These episodes are characterized by numerous earthquakes and significant soil uplifts, often reaching several centimeters or even meters within each cycle. Seismicity in this region rises substantial concern, as it is a primary precursor to potential volcanic eruptions. Additionally, the intense urbanization of the area amplifies the seismic and volcanic risk increasing the population concern. The last unrest phase began in 2006 and is still ongoing. It is accompanied by a large number of earthquakes mainly concentrated beneath the Solfatara-Pisciarelli system, accompanied by the increment of gas emission in Pisciarelli and significant variations in geochemical and geophysical parameters.In this study we present two classes of seismic models generated using passive methods employing earthquakes recorded from 2005 to November 2023 and continuous ambient noise recorded at 20 stations between 2012 and 2021. These models reveal the existence of high P-wave velocity bodies within the caldera: one onshore, located between the port of Pozzuoli and Solfatara, and another offshore, located a few kilometers south of Pozzuoli. The body beneath Pozzuoli and Solfatara lies at 3.0 km deep, exhibiting high Vp/Vs ratios suggesting it is rich in fluids and possibly contributing to the current unrest. Ambient noise tomography shows that both anomalous bodies are linked to the structures at the edge of the resurgence block forming the central part of the coast of the Pozzuoli Gulf, which is responsible for the uplift of the marine terraces. These findings suggest that the peripheral structures may influence the upward fluid migration, playing a role in the sustaining the ongoing unrest.

Effect of ignition timing on combustion characteristics and emissions of an X-type rotary engine with the high efficiency hybrid cycle

X-type rotary engines (XREs), using the high efficiency hybrid cycle, possess advantages of simple structure, high power-to-weight ratio, and high theoretical efficiency, making XREs as potential power sources in hybrid vehicles and small unmanned aerial vehicles. Typically, ignition timing has a promising potential to improve the combustion performance of spark ignition engines. In this work, the effects of ignition timing on flame propagation, combustion characteristics, and pollutants formation were studied adopting a three-dimensional simulation method. The results showed that at different engine speeds, significantly different flow forms and flow velocities in the larger chamber recess of the XRE were formed, resulting in large differences in flame propagation velocities at leading side and trailing side of the combustion chamber. Advancing ignition timing increased the flame propagation velocity at the given engine speed. Ignition timing had a more significant effect on peak pressure at medium-high speeds compared to low engine speeds. At 3000 RPM and 5000 RPM, the peak pressure was increased significantly with advancing ignition timing, but when ignition timing was advanced to -30 °CA, the increment in the in-housing pressure was minimal. As ignition timing was retarded, the ignition delay was slowly reduced. The effect of ignition timing on ignition delay was more significant for low speeds than for medium-high speeds. However, the influence of ignition timing on combustion duration showed the opposite trend. Delayed ignition showed a slight increase in indicated thermal efficiency and indicated mean effective pressure at low speeds, while the opposite was true at medium-high speeds. Nevertheless, the effect of ignition timing and engine speed on indicated specific fuel consumption is opposite to the trend of the above laws. With the increase of ignition timing, the NOx mass fraction first increased and then decreased at low speeds, with the maximum occurred at -30 °CA, but the NOx mass fraction continued to increase at high speeds. Soot and CO productions were slightly affected by ignition timing. To sum up, this XRE, setting the ignition timing of -30 °CA, achieved better flame propagation and engine performance at the price of a smaller increment of NOx emissions.

Climate adaptation through crop migration requires a nexus perspective for environmental sustainability in the North China Plain.

Crop migration can moderate the impacts of global warming on crop production, but its feedback on the climate and environment remains unknown. Here we develop an integrated framework to capture the climate impacts and the feedback of adaptation behaviours with the land-water-energy-carbon nexus perspective and identify opportunities to achieve the synergies between climate adaptation and environmental sustainability. We apply the framework to assess wheat and maize migration in the North China Plain and show that adaptation through wheat migration could increase crop production by ~18.5% in the 2050s, but at the cost of disproportional increment in land use (~19.2%), water use (~20.2%), energy use (~19.5%) and carbon emissions (~19.9%). Irrigation and fertilization management are critical mitigation opportunities in the framework, through which wheat migration can be optimized to reduce the climatic and environmental impacts and avoid potential carbon leakage. Our work highlights the sustainable climate adaptation to mitigate negative environmental externalities.

Deterioration and age governed greenhouse gas emissions from the product itself: an optimum inventory control problem

Greenhouse gas emissions contribute significantly to global warming. This occurs during various operations, including the production, storage, and transportation of an inventory, but in some cases, the inventory itself becomes the emission source. Emissions from cattle dunk cakes, livestock slurry, manure, crude oil, and gasoline can be considered examples of this type of emissions. This paper proposes a mathematical formulation for a deteriorating inventory model utilizing the inventory as a source of emissions. The model is developed under inflation. Other activities, such as energy consumption for warehousing, are considered to be contributing to greenhouse gas emissions here. The rate of emissions from the product is exponentially governed by the rate of deterioration and the age of the material. The trapezoidal-type demand rate is considered using the Heaviside step function. Shortages are permitted but partially backlogged, and the backlogging rate is supposed to be decreasing exponentially with the increased waiting time. The numerical illustration of the model is provided to illustrate the mathematical expressions, and the effect of parametric variation is reported to give managerial insights. The results reveal that the greenhouse gas emissions are proportional to the variable rate of emissions cost and the deterioration rate. However, the increment in total emissions with respect to variable emissions cost increases with the deterioration rate. If the deterioration rate is negligible, total carbon emissions do not fluctuate much, but it increases rapidly if it is relatively high. The preservation technology is used to reduce deterioration and helps reduce emissions.

How do fintech, digitalization, green technologies influence sustainable environment in CIVETS nations? An evidence from CUP FM and CUP BC approaches.

The natural resource curse highlights the paradox that nations with enormous reserves endure slower economic expansion than those with limited resources. On the other hand, fintech is revolutionizing the business community while setting the basis for long-lasting growth in CIVETS nations. The ongoing analysis analyzes the topic of ample natural resources promoting economic expansion. The ongoing analysis illuminates the case for CIVETS nations by applying the novel panel data models, the CUPFM and CUPBC tests, through which the analysis authenticates those natural resources augment carbon dioxide emissions. The analysis has taken the period 2000 to 2022. Policy practitioners discover the linkage very inspiring. Natural resources expedite an increment in carbon dioxide emissions in the selected panel. In addition, digitalization and fintech abate the emissions, whereas green technologies must be promoted in these nations for environmentally friendly development. Regarding the outcomes, think tanks should formulate policies encouraging sustainable environment. It incorporates the sustainable usage of natural resources and financing in and boosting fintech. Furthermore, it is mandatory to encourage digitalization and green technologies in the observed nations.

Behavior analysis of Low-Heat Rejection engine powered by biodiesel under varied exhaust gas recirculation ratios

ABSTRACT The key focus areas of the internal combustion engine architecture are energy effectiveness and greater thermal efficiency since 1/3 of the produced heat energy vanishes on the way to the atmosphere and the coolant. Experiments have looked into the viability of using tamanu biodiesel in a thermally insulated diesel engine. The engine was first put through its paces on regular diesel fuel as a comparison baseline. After that, the piston, exhaust, intake valve and cylinder head surfaces were coated with partially stabilized zirconia (PSZ) to act as thermal insulation for the engine. The engine coating was developed to improve the efficiency of the engine’s use of biodiesel blends by decreasing heat loss through the chamber walls with a thickness of 200 micrometers (µm). In addition, mixes of Tamanu biodiesel with diesel fuel were tested, including B10, B20, B30, and B100, to examine how these mixtures would influence the performance of the ceramic-coated low heat rejection (LHR) engine compared to the performance of the base diesel engine. Additionally, the impacts of different exhaust gas recirculation (EGR) ratios on the operation of biodiesel-powered LHR engines were analyzed. The zirconia insulated LHR engine running on B20 performed the best, with a thermal efficiency of 28.57% and a brake specific energy consumption that was considerably lower than that of the baseline diesel engine. In addition, the LHR engine for B20 reduces carbon monoxide (CO) and smoke emissions by 17% and 21.4%, respectively, compared to the B20-powered base diesel engine, although nitrogen oxide (NOx) emissions slightly increase. However, the addition of 15% EGR to the B20-LHR engine produced a minor increment in hydrocarbon (HC), CO and smoke emissions, corresponding to 19.7% and 25.4%, respectively. By implementing 15% EGR with B20-LHR, the NOx level is reduced by 25.4% due to diluting the air-fuel mixture. The combination of 15% EGR with B20 for a thermal barrier-coated engine offers significant improvement by increasing engine performance and reducing emission characteristics.

European CH4 inversions with ICON-ART coupled to the CarbonTracker Data Assimilation Shell

Abstract. We present the first application of the ICOsahedral Nonhydrostatic model with Aerosols and Reactive Trace gases (ICON-ART) in inverse modeling in inverse modeling of greenhouse gas fluxes with an ensemble Kalman smoother. For this purpose, we extended ICON-ART to efficiently handle gridded emissions, generate an ensemble of perturbed emissions during runtime and use nudging on selected variables to keep the simulations close to analyzed meteorology. We show that the system can optimize total and anthropogenic European CH4 fluxes on a national scale in an idealized setup using pseudo-observations from a realistic network of measurement stations. However, we were unable to constrain the sum of the natural emission sources of comparatively low magnitude. Also regions with low emissions and regions with low observational coverage could not be optimized individually for lack of observational constraints. Furthermore, we investigated the sensitivities towards different inversion parameters and design choices with 15 sensitivity runs using the same idealized setup, demonstrating the robustness of the approach when regarding some minimal requirements of the setup (e.g., number of ensemble members). Subsequently, we applied the system to real in situ observations from 28 European stations for three years, 2008, 2013 and 2018. We used a priori anthropogenic fluxes from the EDGARv6 inventory and a priori natural fluxes from peatlands and mineral soils, inland waters, the ocean, biofuels and biomass burning, and geology. Our results for the year 2018 indicate that anthropogenic emissions may be underestimated in EDGARv6 by ca. 25 % in the Benelux countries and, to a smaller degree, in northwestern France and southern England. In the rest of the domain, anthropogenic fluxes are corrected downwards by the inversion, suggesting an overestimation in the a priori. For most countries, this means that the a posteriori country-total anthropogenic emissions are closer to the values reported to the United Nations Framework Convention on Climate Change (UNFCCC) than the a priori emissions from EDGARv6. Aggregating the a posteriori emissions across the EU27 + UK results in a total of 17.4 Tg yr−1, while the a priori emissions were 19.9 Tg yr−1. Our a posteriori is close to the total reported to the UNFCCC of 17.8 Tg yr−1. Natural emissions are reduced from their a priori magnitude almost everywhere, especially over Italy and Romania–Moldova, where a priori geological emissions are high, and over the United Kingdom and Scandinavia, where emissions from peatlands and wetlands were possibly unusually low during the hot and dry summer of 2018. Our a posteriori anthropogenic emissions for the EU27 + UK fall within the range estimated by global top-down studies but are lower than most other regional inversions. However, many of these studies have used observations from different measurement stations or satellite observations. The spatial pattern of the emission increments in our results, especially the increase in the Benelux countries, also agrees well with other regional inversions.

Assessing climate/air quality synergies and cost-effectiveness for Beijing transportation: Insights into sustainable development

CO2 emission reduction policies can simultaneously reduce air pollutant emissions in the transport sector, but the extent of their cost-effective is under-evaluated. To explore sustainable transportation in a mega-city, the potential synergies and cost-effectiveness of CO2 and air pollutant emission reductions in Beijing transportation are quantitatively evaluated by radar chart analysis, total cost of ownership (TCO) and marginal abatement cost curves (MACC) under various mitigation measures. The findings show that the adoption of electric light-duty vehicles can achieve a significant synergistic effect and cost-effectiveness of emission reductions, and would be implemented as a high priority. Moreover, improving emission standards and fuel economy have an obvious cost-effectiveness and effective mitigation for air pollutants, but with poor synergies due to low CO2 mitigation. In contrast, the clean energy for large and heavy vehicles, and bio-fuel for aviation are essential measures for achieving carbon neutrality, but with high costs. Furthermore, changes of transport modes have good cost-effectiveness, but there are no synergies due to the emission increments of PM2.5 and NOx. Given that transportation plays a crucial role in achieving carbon neutrality and enhancing air quality, more stringent and effective environmental policies targeting emission reduction can expedite the sustainable transition in Beijing transportation.

Investigation on the Engine Parameters of a DI Diesel Engine using Diesel and Canola Biodiesel-blended Fuel with 1-4 Dioxane Additive

The present work investigates the effect of 1-4 dioxane (10 ml) as additive to the diesel and blend of canola biodiesel (CABD20) on the performance of a diesel engine. The physiochemical properties of diesel, CABD20, diesel+1-4 dioxane and CABD20+1-4 dioxane fuels were measured and improved fuel properties were identified with the additive based fuels. From the experimental results, BTE was enhanced (by 1.9-2.2%) with additive based fuel over both the diesel and CABD20 fuels. The presence of HA, CO and smoke emissions were decreased in the exhaust emissions for CABD20 fuel with a marginal increment of NOx emissions. Furthermore, adding 1-4 dioxane to diesel and CABD20 fuel significantly reduced the exhaust emissions. From the observations, it is concluded that better engine performance can be obtained with the use of additives in the diesel and the blend of biodiesel.

Impacts of aboveground litter and belowground roots on soil greenhouse gas emissions: Evidence from a DIRT experiment in a pine plantation

Plant detritus alteration may influence soil greenhouse gas emissions, but the direction, extent and mechanisms remain uncertain. Here we conducted a DIRT (Detritus Input and Removal Treatment) experiment in a Pinus sylvestris var. mongolica plantation in Saihanba (Hebei Province, China), manipulating aboveground litter (L-: litter removal, L: normal litter, L+: litter doubling) and belowground roots (R-: root removal, R: with root) resulting in six treatments. We measured CO2, N2O, and CH4 fluxes during 2019 and 2020 growing seasons, along with soil physicochemical, enzymatic and microbial variables. Our findings revealed that soil CO2 and N2O emissions increased with litter input, while CH4 uptake decreased. The absence of roots decreased soil CO2 emission and CH4 uptake but increased N2O emission. Aboveground litter enhanced the carbon cycling variables, such as extractable organic carbon (EOC), the ratio of soil extractable organic carbon to extractable total nitrogen (EOC:ETN), soil carbon mineralization rate (Cmin), and peroxidase activity (PER), resulting in increased CO2 emission. In contrast, the absence of roots increased the nitrogen cycling variables, such as soil extractable total nitrogen (ETN), nitrate nitrogen content (NO3−-N), the ratio of soil extractable organic carbon to extractable total nitrogen (EOC:ETN), soil net nitrogen mineralization rate (Nmin), and the abundance of ammonia-oxidizing bacteria (AOB), leading to increased N2O emission. Moreover, soil CH4 uptake was mainly influenced by soil microclimate: aboveground litter input reduced CH4 uptake by lowering soil temperature, while belowground roots benefited CH4 uptake via reducing soil moisture by water uptake. Taken together, our study suggests that soil CO2, N2O, and CH4 emissions (or uptake) are influenced by both aboveground and belowground plant inputs through various pathways. While aboveground litter input promotes the emissions of greenhouse gasses, the mitigating effect of belowground roots on N2O and CH4 partially offsets the increment of CO2 emission in this plantation.

Introducing new green machining technology to enhance process performance and reduce environmental pollution in the metal processing industry.

The pursuit of enhanced cooling and lubrication methods for machining processes that are energy-efficient, environmentally friendly, and cost-effective is receiving significant attention from both academia and industry. The reduction of CO2 emissions is closely tied to electrical and embodied energy consumption. This study introduces a novel LN2 oil-on-water (LNOoW) cooling/lubrication (lubricooling) approach for the machining of Ti-6Al-4V alloy. Machinability aspects, energy-related aspects, environmental-related aspects, and economic aspects are measured and compared. More specifically, surface quality, electrical energy, cutting forces, and tool wear were measured in machinability aspects. Similarly, specific total energy and specific cumulative Energy Demand (S_CED), specific carbon emission, and production costs were measured to investigate the energy and environmental and economic aspects, respectively. The LNOoW provided the best machinability results compared with other approaches. Result found that LNOoW produced 37.5% better surface quality, removed 159.17% more material, and reduced 50.56% specific cutting energy and 53.63% specific costs as compared to traditional dry cutting conditions. The 39% increment in specific carbon emissions observed in the LN2 oil-on-water (LNOoW) approach in comparison to the dry-cutting method can be mitigated through the implementation of sustainable practices in the production of liquid nitrogen (LN2). The information provided in this study serves as a valuable resource for the development of environmentally friendly machining processes. The study also helps get the sustainable development goals (SDGs) of the United Nations.

Global Scale Inversions from MOPITT CO and MODIS AOD

Top-down observational constraints on emissions flux estimates from satellite observations of chemical composition are subject to biases and errors stemming from transport, chemistry and prior emissions estimates. In this context, we developed an ensemble data assimilation system to optimize the initial conditions for carbon monoxide (CO) and aerosols, while also quantifying the respective emission fluxes with a distinct attribution of anthropogenic and wildfire sources. We present the separate assimilation of CO profile v9 retrievals from the Measurements of Pollution in the Troposphere (MOPITT) instrument and Aerosol Optical Depth (AOD), collection 6.1, from the Moderate Resolution Imaging Spectroradiometer (MODIS) instruments. This assimilation system is built on the Data Assimilation Research Testbed (DART) and includes a meteorological ensemble to assimilate weather observations within the online Community Atmosphere Model with Chemistry (CAM-chem). Inversions indicate an underestimation of CO emissions in CAMS-GLOB-ANT_v5.1 in China for 2015 and an overestimation of CO emissions in the Fire INventory from NCAR (FINN) version 2.2, especially in the tropics. These emissions increments are consistent between the MODIS AOD and the MOPITT CO-based inversions. Additional simulations and comparison with in situ observations from the NASA Atmospheric Tomography Mission (ATom) show that biases in hydroxyl radical (OH) chemistry dominate the CO errors.

Examination of the effect on the engine of diesel-nanoparticle mixture with natural gas addition

Diesel engines have a broader application area and have a significant share in the transportation sector. Although there are restrictions on producing within the scope of emission standards, diesel fuel will remain important in heavy-duty vehicles for some time. Therefore, studies continue for environmentally friendly combustion and low emissions in diesel fuel. This paper reveals the results of using nanoparticle fuel with natural gas (NG) on diesel engine emissions and performance. In the experiments, the motor load was adjusted from no to full load by increasing it at 25% intervals. Three different diesel-nanoparticle blends containing 25 ppm, 50 ppm and 75 ppm carbon nanotube (CNT) were prepared and each of these blends was tested both with and without NG. In light of the test results, it has been seen that the D75ppmCNT + NG mixture is the best fuel mixture compared to both diesel and nanoparticle-added diesel since it provides the highest value in brake thermal efficiency (BTE) and the lowest value in brake specific fuel consumption (BSFC) at full load conditions. In the case of using a D75ppmCNT mixture, around 29% decrease in BSFC and about 28% increase in BTE were observed according to the diesel fuel use. In terms of emissions, when NG is added to the D + CNT fuel mixtures, there is an increment in CO and HC emissions and a slight reduction in NOx emissions at low and medium load.

Experimental study on the effect of limestone on SO2 and NO emission characteristics during coal/coke combustion

Adding limestone to coal combustion reduces SO2 emissions but sometimes increases NO emissions, posing a challenge for synergistic SO2 and NO control in circulating fluidized bed (CFB) boilers. Limestone in the CFB furnace can participate in the conversion of sulfur and nitrogen compounds from coal and its devolatilized coke. This study compared the effects of limestone on SO2 and NO emission characteristics during coal/coke combustion to explore the potential for controlling both emissions. Combustion experiments were conducted in a fixed-bed reactor under different reaction parameters including Ca/S mole ratio, oxygen concentration, and temperature. Results showed that SO2 emissions decreased and NO emissions increased with increasing Ca/S mole ratio for both fuels. Comparing the emissions from fuels with and without limestone addition, a lower oxygen concentration decreased the desulfurization efficiency and the increment of NO emissions caused by limestone for both fuels. Temperature had opposite effects of limestone on coal or coke combustion. For coke, higher temperatures improved desulfurization efficiency and decreased the increment of NO emissions caused by limestone. For coal, the effects were reversed. To explain the impact of temperature, the sulfur and nitrogen migration paths affected by limestone were analyzed based on the XPS results of the fuels. Thiophene-S and N-Q became the main sulfur and nitrogen components in coke at high temperatures. The conversion of thiophene-S into SO2 is slow, and the limestone is calcined more fully during coke combustion, improving the utilization rate of limestone. N-Q tends to be converted into NH3. Further, NO is reduced by NH3 over the catalyze of CaO at low oxygen conditions. This reaction process decreases the increment of NO emissions caused by limestone.

Decoupling CO2 Emissions from Economic Growth in China’s Cities from 2000 to 2020: A Case Study of the Pearl River Delta Agglomeration

As one of the most densely populated, economically developed, and outwardly open urban agglomerations in China, the Pearl River Delta (PRD) urban agglomeration is a key player in achieving China’s carbon peak and carbon neutrality targets. This study analyzes low-emission development by examining the evolutionary patterns of carbon dioxide (CO2) emissions and the decoupling relationship between economic growth and CO2 emissions, using the latest available data from 2000 to 2020. Here are the main findings: (1) We found a significant fluctuation in the decoupling statuses between economic advancements and CO2 emissions within the PRD domain. Predominantly, a weak decoupling scenario was observed, where economic proliferations were paralleled by nearly equivalent increments in CO2 emissions. (2) The growth rate of carbon emissions increased significantly relative to economic expansion during 2015–2020, especially pronounced in cities such as Guangdong, Zhuhai, Foshan, and Dongguan. This delineates the persistent challenges in steering towards a pathway of energy conservation and emission abatement in the region. (3) Furthermore, a differential role of elasticity factors was noted across cities: Guangzhou and Shenzhen witnessed a significant influence of energy-saving elasticity in fostering a decoupling between economic surge and CO2 emissions, whereas in other cities, the emphasis shifted towards emission-reduction elasticity as a more vital determinant. The results of this study are of great significance for guiding policy makers and stakeholders in urban clusters across China and in similar regions globally to achieve low carbon development goals.

Estimation of Air Pollutant Emissions by Tractor Utilization in Korea

The utilization of tractors is essential because of both the shortage of agricultural labor forces and the rapid aging of farmers in Korean agriculture. Tractors can be classified into two types: a walking tractor called as a power tiller, and a riding tractor. In this study, diesel emission inventories of tractors were established and variations of air pollutants were analyzed with each other using 2011 and 2019 survey data in Korea. Agricultural tractors including walking and riding types, which were categorized into three levels via the rated output power, were the main sources of diesel emissions. The emission inventory including CO, NOx, SOx, TSP(PM10), PM2.5, VOCs, and NH3 were established using a Tier 3 methodology. The total amount of emissions using agricultural tractors was decreased by about 13% from 2011 to 2019. The number of walking tractors were decreased by about 19% in 8 years; on the other hand, that of riding tractors were increased by about 12%. However, the emission reduction is about 48% for walking tractors, and the emission increment is about 5% for riding tractors. Thus, the total emission from agricultural tractors was decreased by about 16% in those periods. It is due to the decrease of 21% and 15% in the hours of use of walking and riding tractors, respectively, in 2019. Walking tractors mainly emit air pollutants from spraying and transporting. Riding tractors emit about 61% of the total air pollutants mainly from soil preparation and transporting operations. The geographic information system (GIS) was used to visualize the distribution of air pollutants in Korea. High-emission generating regions and the changes of emissions over 8 years were clearly seen in the GIS analysis. High air-pollutant emitting regions are mainly located in the western and southern regions of Korea, which have plenty of arable areas compared to other regions in Korea.

Double-edged sword of technological progress to climate change depends on positioning in global value chains.

Technological progress (TP) is a double-edged sword to global climate change. This study for the first time reveals rebound and mitigation effects of efficiency-related TP in global value chains (GVCs) on greenhouse gas (GHG) emissions. The integrated effects of TP depend on the positioning of sectors in GVCs. The cost-saving TP in upstream sectors would stimulate downstream demand. This produces stronger rebound effects than mitigation potentials and leads to global GHG emission increments (e.g. TP in the gas sector of China and petroleum and coal products sector of South Korea). In contrast, sectors located in the trailing end of GVCs have greater potentials for GHG emission mitigation through TP, mainly due to the reduction of upstream inputs. (e.g. the construction sector of China and dwelling sector of the United States). Global GHG emissions and production outputs can be either a trade-off or a win-win relationship on account of TP than rebound effects, because TP in different sectors could possibly increase or decrease the emission intensity of GVCs. This study could recognize the most productive spots for GHG emission mitigation through efficiency-related TP. It provides a new perspective for international cooperation to promote global GHG emission mitigation.

Performance and life cycle assessment of pillow plate heat exchanger utilizing microencapsulated phase change material slurry

The pillow plate heat exchanger is a promising and relatively new heat exchanger design that enhances heat transfer by augmenting flow turbulence. This study focuses on further enhancing the heat exchanger’s performance by utilizing Microencapsulated Phase Change Material (MPCM) slurry which increases the heat capacity of the working fluid. So, the heat transfer characteristics, flow performance, and life cycle assessment of the pillow plate heat exchanger when employing MPCM slurry with varying particle concentrations are evaluated. The investigation takes into account the intricate phenomenon of conjugate heat transfer between channels, enabling a comprehensive analysis of the system's behaviour. To avoid modelling errors, a lab-scale heat exchanger is simulated instead of using periodic boundary conditions to capture the effects of both developing and fully developed regions. The results showed that temperature distribution in the heat exchanger is highly affected by developing regions in both inner and outer channels. Meanwhile, by adding MPCM, a better cooling performance with a lower temperature variation in cold temperatures is provided at the cost of a higher pressure drop. However, 6.2% enhancement in the heat transfer rate is achieved by using a 15% MPCM concentration which is a considerable amount in thermal management systems in industries requiring efficient heat dissipation, such as electronics cooling. The Life Cycle Assessment indicated that although there is a slight increment in emissions as the concentration of MPCM increases, the overall impact is minimal on the environment.

Nanomolar “Turn-On” Hg2+ detection by a fluorescein based fluorescent probe: DFT calculations, bioimaging and on-site assay kit studies

Sensitive yet rapid methodologies for efficient recognition of toxic heavy metals, like Hg2+, would avert the poisonous impacts of these elements on the environment and human health. Herein, we present a highly selective fluoresceine-based fluorogenic probe FP for Hg2+ recognition with quick response, an impressive LOD of 67.1 nM, high sensitivity, and a linear emission increment relationship with Hg2+ concentration (0–20.0 μM). FP could specifically recognize Hg2+ and it exhibited a 250-fold emission enhancement at 515 nm to Hg2+, but no response to other common cations. The mechanism for FP-Hg2+ was completely examined through FTIR, 1H NMR, TOF-MS, and density functional theory (DFT) calculations. To examine naked-eye recognition of Hg2+, the FP-coated silica plates, and cotton swabs were productively manufactured for the sensing of Hg2+. Besides, FP was able to recognize Hg2+ in biological systems with excellent efficiency. Overall, ultra-fast recognition property of FP for Hg2+, high sensitivity, and selectivity of FP against Hg2+ could be conveniently utilized to prevent the toxicity of Hg2+.

Impacts of forest cover change on carbon stock, carbon emission and land surface temperature in Sor watershed, Baro Akobo Basin, Western Ethiopia

Abstract Human-induced actions aggravate forest degradation and result in carbon emissions. Increment of carbon emission raises land surface temperature (LST) and contributes to climate change. The aim of this study was to assess the impacts of forest cover change on carbon stocks, carbon emissions and LST over the period 1992–2022 using geospatial techniques in the Sor watershed, Western Ethiopia. The results revealed that forest land declined by 336.6 km2 due to the expansion of agricultural land with an area of 274.9 km2. Results show a decline in carbon stock of 58,883.4 tons/km2 while annual carbon emission exhibited an increasing trend of 2,418,083.91 tons to the atmosphere over the past three decades. As vegetation declined, LST increased by an average of 3.7 °C over the past three decades. All actors, including government and non-governmental organizations, should contribute to tree planting and reafforestation programmes to minimize the increasing trend of LST and carbon emissions. Furthermore, we need to build a climate-resilient green economy to protect people from the negative impacts of climate change.