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Wetland ecosystems store large amounts of carbon, and CO 2 and CH 4 fluxes from this ecosystem receive the double impact of climate change and human activities. Nonetheless, research on how multi-gradient warming and nitrogen and phosphorus additions affect these wetland greenhouse gas emissions is still limited, particularly in alpine wetland ecosystems. Therefore, we conducted a field experiment on the Tibetan Plateau wetlands, investigating the effects of warming and nitrogen and phosphorus additions on the CO 2 and CH 4 fluxes in alpine wetlands. Results indicated that warming enhanced the CO 2 absorption and CH 4 emission in the alpine meadow ecosystem, possibly related to changes in plant growth and microbial activity induced by warming, while we noticed that the promotion of CO 2 uptake weakened with the increase in the magnitude of warming, suggesting that there may be a temperature threshold beyond which the ecosystem's capacity for carbon sequestration may be reduced. Nitrogen addition increased CH 4 emission, with the effect on CO 2 absorption shifting from inhibition to enhancement as the amount of applied nitrogen or phosphorus increased. The interaction between warming and nitrogen and phosphorus additions further influenced CH 4 emission, exhibiting a synergistic enhancement effect. This study deepens our understanding of the greenhouse gas responses of alpine wetland ecosystems to warming and nitrogen and phosphorus additions, which is significant for predicting and managing ecosystem carbon balance under global change.

This decoupling between carbon dioxide emissions and the heavy industry is one of the main topics of government managers. This paper uses the quantile regression approach to investigate the carbon intensity of China's heavy industry, based on 2005-2019 panel data. The main findings are as follows: (1) incentive-based environmental regulations have the greater impact on the carbon intensity in Jiangsu, Shandong, Zhejiang, Henan, Liaoning, and Shaanxi, because these provinces invest more in environmental governance and levy higher resource taxes; (2) the impact of mandatory environmental regulations on carbon intensity in Beijing, Tianjin, and Guangdong provinces is smaller, since these three provinces have the fewest enacted environmental laws and rely mainly on market incentives; (3) conversely, foreign direct investment has contributed most to carbon intensity reduction in Tianjin, Beijing, and Guangdong provinces, because these three have attracted more technologically advanced foreign-funded enterprises; (4) technological progress contributes more to the carbon intensity in the low quantile provinces, because these provinces have more patented technologies; (5) the carbon intensity of Shaanxi, Shanxi, and Inner Mongolia provinces is most affected by energy consumption structures because of their over-reliance on highly polluting coal.

It is of pivotal significance to explore robust photocatalysts to promote the photoreduction of CO 2 into solar fuels. Herein, an intelligent metal-insulator-semiconductor (MIS) nano-architectural photosystem was constructed by electrostatic self-assembly between cetyltrimethylammonium bromide (CTAB) insulator-capped metal Ni nanoparticles (NPs) and covalent triazine-based frameworks (CTF-1). The metal-insulator-CTF composites unveiled a substantially higher CO evolution rate (1254.15 μmol g -1  h -1 ) compared with primitive CTF-1 (1.08 μmol g -1  h -1 ) and reached considerable selectivity (98.9 %) under visible-light irradiation. The superior photocatalytic CO 2 conversion activity over Ni-CTAB-CTF nanoarchitecture could be attributed to the larger surface area, reinforced visible-light response, and CO 2 capture capacity. More importantly, the Ni-CTAB-CTF nanoarchitecture endowed the photoexcited electrons on CTF-1 with the ability to tunnel across the thin CTAB insulating layer, directionally migrating to Ni NPs and thereby leading to the efficient separation of photogenerated electrons and holes in the photosystem. In addition, isotope-labeled ( 13 CO 2 ) tracer results verified that the reduction products come from CO 2 rather than the decomposition of the photocatalysts. This study opens a new avenue for establishing a highly efficient and selective artificial photosystem for CO 2 conversion., (© 2022 Wiley-VCH GmbH.)

It is of pivotal significance to explore robust photocatalysts to promote the photoreduction of CO2 into solar fuels. Herein, an intelligent metal‐insulator‐semiconductor (MIS) nano‐architectural photosystem was constructed by electrostatic self‐assembly between cetyltrimethylammonium bromide (CTAB) insulator‐capped metal Ni nanoparticles (NPs) and covalent triazine‐based frameworks (CTF‐1). The metal‐insulator‐CTF composites unveiled a substantially higher CO evolution rate (1254.15 μmol g−1 h−1) compared with primitive CTF‐1 (1.08 μmol g−1 h−1) and reached considerable selectivity (98.9 %) under visible‐light irradiation. The superior photocatalytic CO2 conversion activity over Ni‐CTAB‐CTF nanoarchitecture could be attributed to the larger surface area, reinforced visible‐light response, and CO2 capture capacity. More importantly, the Ni‐CTAB‐CTF nanoarchitecture endowed the photoexcited electrons on CTF‐1 with the ability to tunnel across the thin CTAB insulating layer, directionally migrating to Ni NPs and thereby leading to the efficient separation of photogenerated electrons and holes in the photosystem. In addition, isotope‐labeled (13CO2) tracer results verified that the reduction products come from CO2 rather than the decomposition of the photocatalysts. This study opens a new avenue for establishing a highly efficient and selective artificial photosystem for CO2 conversion. [ABSTRACT FROM AUTHOR]

Across Canada's boreal forest, disturbances from in situ oil sands mining, including well‐pads, significantly impact vast areas of the landscape. The creation of well‐pads requires removal of vegetation and placement of mineral fill, which essentially stops any carbon (C) sequestration on the once peatland ecosystem. It is important that, once no longer in use, these well‐pads are restored as long‐term C (peat) accumulation is what defines peatland ecosystem. However, little is known about the recovery of greenhouse gas exchange post‐restoration of these features. We studied a decommissioned well‐pad located in a treed poor fen that was restored using three soil adjustment treatments (SATs): (1) complete mineral fill removal (Peat‐Dec); (2) partial pad removal and burial under peat layer (BUPL); and (3) mixing mineral and peat by inversion (Mixed‐P‐M). The recreated peat surface was revegetated with donor peatland species using the moss layer transfer technique (MLTT). The objectives of this paper were to (1) quantify plot‐scale seasonal carbon dioxide (CO2) and methane (CH4) exchange of the SATs, 2–4 years post‐restoration compared to reference sites and (2) determine the influence of several environmental variables on CO2 and CH4 exchange. All SATs proved effective in recreating a soil surface needed to support peatland vegetation as shown by similar rates of net ecosystem exchange (NEE). Equally, both types of vegetation reintroduced led this site on a trajectory toward functioning as a net C sink. [ABSTRACT FROM AUTHOR]

The development of effective photocatalysts for CO 2 photocatalytic reduction is a crucial step in resolving environmental and energy-related problems. The Schottky heterostructure of Ag/C 3 N 5 has been constructed to improve its photocatalytic activity by utilising the surface plasmon resonance effect of Ag. Notably, Ag/C 3 N 5 exhibited a remarkable 100% selectivity for CH 4 without the use of any sacrificial reagents under the condition of visible light, and the productivity reached 1.1 μmol·g−1·h−1 as compared with 0.4 μmol·g−1·h−1 for pure C 3 N 5. Experiments and density functional theory (DFT) calculations have proven that when Ag and C 3 N 5 come into contact, the Schottky junction formed between them promotes the aggregation of photogenerated electrons to the Ag surface, which is favourable to the efficiency of electron–hole separation. Simultaneously, Ag acts as the active site of the reaction to promote CH 4 generation. We expect that this simple method based on low-cost C 3 N 5 can be extended to the preparation of metal–C 3 N 5 heterojunctions and applied to CO 2 photocatalytic reduction processes with high product selectivity. [Display omitted] ● Ag/C 3 N 5 Schottky heterojunctions were prepared by a baking method. ● Ag/C 3 N 5 shows 100% selectivity of CH 4 for CO 2 photocatalytic reduction. ● The active site of the reaction was identified using density functional theory calculations. [ABSTRACT FROM AUTHOR]

Photocatalytic CO2 reduction into carbonaceous feedstock chemicals is a promising renewable energy technology to convert solar energy and greenhouse gases into chemical fuels. Here, a covalent triazine‐based framework (CTF) is demonstrated as an efficient cocatalyst to reduce CO2 under visible‐light irradiation. The nitrogen‐rich triazine moieties in CTF contribute to CO2 adsorption, while the periodical pore structure of CTF favors the accommodation of CO2 and electron mediator. Immobilization of cobalt species onto CTF promotes the photocatalytic activity with a 44‐fold enhancement over pristine CTF and the optimal CO production rate of the obtained Co/CTFs was up to 50 μmol g−1 h−1. The results of solid‐state UV‐vis diffuse reflectance spectra (UV‐vis DRS), CO2 adsorption and electrochemical impedance spectroscopy (EIS) illustrated that the increased activity was ascribed to the enhanced CO2 capture capacity, improved absorption of visible‐light and facilitated the transfer of charge from CTF to CO2 molecules. The CTF not only serves as a substrate for active Co species, but also bridges the photosensitizer with cobalt catalytic sites for the efficient transfer of photoexcited electrons. This work highlights the capability and ease of fabricating covalent organic framework‐based photocatalytic systems that are potentially useful for energy‐conversion applications. [ABSTRACT FROM AUTHOR]

Across Canada's boreal forest, linear disturbances, including cutlines such as seismic lines and roads, crisscross the landscape to facilitate resource exploration and extraction; many of these linear disturbances cross peatland ecosystems. Changes in tree canopy cover and the compression of the peat by heavy equipment alter local thermal, hydrological, and ecological conditions, likely changing carbon exchange on the disturbance, and possibly in the adjacent peatland. We measured bulk density, water table, soil temperature, plant cover, and CO2 and CH4 flux along triplicate transects crossing a winter road through a wooded fen near Peace River, Alberta, Canada. Sample plots were located 1, 5, and 10 m from the road on both sides with an additional three plots on the road. Productivity of the overstory trees, when present, was also determined. The winter road had higher bulk density, shallower water table, higher graminoid cover, and thawed earlier than the adjacent peatland. Tree productivity and CO2 flux varied between the plots, and there was no clear pattern in relation to distance from the road. The plots on the winter road acted as a greater CO2 sink and greater CH4 source compared to the adjacent peatland with plots on the winter road emitting on average (standard error) 479 (138) compared to 41 (10) mg CH4 m−2 day−1 in the adjacent peatland. Considering both gases, global warming potential increased from 70 to 250 g CO2e m−2 year−1 in the undisturbed area to 2100 g CO2e m−2 year−1 on the winter road. Although carbon fluxes on any given cutline through peatland will vary depending on level of compaction, line width and vegetation community shifts, the large number of linear disturbances in Canada's boreal forest and slow recovery on peatland ecosites suggest they could represent an important anthropogenic greenhouse gas source. [ABSTRACT FROM AUTHOR]

The mass transfer performance of CO2 absorption into blended N,N-diethylethanolamine (DEEA)/ethanolamine (MEA) solutions was investigated using a lab-scale absorber (H = 1.28 m, D = 28 mm) packed with Dixon ring random packing. The mass transfer coefficient KGav, the unit volume absorption rate Φ, outlet concentration of CO2 (yCO2), and the bottom temperature Tbot of CO2 in aqueous DEEA/MEA solutions were determined over the feed temperature range of 298.15-323.15 K, lean CO2 loading of 0.15-0.31 mol/mol, over a wide range of liquid flow rate of 3.90-9.75 m3/m2-h, by using inert gas flow rate of 26.11-39.17 kmol/m2-h and 6-18 kPa CO2 partial pressure. The results show that liquid feed temperature, lean CO2 loading, liquid flow rate, and CO2 partial pressure had significant effect on those parameters. However, the inert gas flow rate had little effect. To allow the mass transfer data to be really utilized, KGav and yout correlations for the prediction of mass transfer performance were proposed and discussed. © 2017 American Institute of Chemical Engineers AIChE J, 63: 3048-3057, 2017 [ABSTRACT FROM AUTHOR]

Currently, global warming, frequent occurrence of extreme weather and air pollution are common problems facing the international community. Carbon dioxide emissions are the root causes of these environmental and climate issues. Due to rapid industrialization and urbanization, China has become the world's largest energy consumer and carbon dioxide emitter. Moreover, the manufacturing industry is highly energy-consuming and pollution-intensive, accounting for nearly 60% of China's total energy consumption and over 50% of total carbon dioxide emissions. Thus, identifying the main drivers of the industry's carbon dioxide emissions is vital for China's emission reduction and global efforts to enhance environmental protection. This study uses Vector Autoregressive model to analyze the influencing factors of the changes in carbon dioxide emissions in the industry. The results show that energy efficiency plays a dominant role in reducing carbon dioxide emissions. Urbanization also has significant effect on carbon dioxide emissions because of large-scale real estate construction and high rate of vehicle ownership. Energy structure has higher impact on emission reduction than industrialization due to massive coal consumption and industrial structure optimization. Therefore, the Chinese government should increase investment in energy-saving technology, optimize energy structure, promote the production and use of new energy and hybrid vehicles. [ABSTRACT FROM AUTHOR]

Novel rare earth metal–zinc heterotrinuclear complexes have been synthesized, which showed high efficiency and selectivity in initiating the copolymerization of CO2 and cyclohexene oxide under mild conditions. Significant cooperation between rare earth metal and zinc centres that account for the good performance is observed. Copolymers of high polycarbonate content (up to 99%) as well as high molecular weight (up to 295 800 g mol−1) were obtained at 25 °C under 0.7 MPa pressure of CO2. [ABSTRACT FROM AUTHOR]

Air quality inside transportation carriages has become a public concern. A comprehensive measurement campaign was conducted to examine the commuters’ exposure to PM 2.5 (d p ⩽ 2.5 μm) and CO 2 in Shanghai metro system under different conditions. The PM 2.5 and CO 2 concentrations inside all the measured metro lines were observed at 84 ± 42 μg/m 3 and 1253.1 ± 449.1 ppm, respectively. The factors that determine the in-carriage PM 2.5 and CO 2 concentrations were quantitatively investigated. The metro in-carriage PM 2.5 concentrations were significantly affected by the ventilation systems, out-carriage PM 2.5 concentrations and the passenger numbers. The largest in-carriage PM 2.5 and CO 2 concentrations were observed at 132 μg/m 3 and 1855.0 ppm inside the carriages equipped with the oldest ventilation systems. The average PM 2.5 and CO 2 concentrations increased by 24.14% and 9.93% as the metro was driven from underground to overground. The average in-carriage PM 2.5 concentrations increased by 17.19% and CO 2 concentration decreased by 16.97% as the metro was driven from urban to the suburban area. It was found that PM 2.5 concentration is proportional to the on-board passenger number at a ratio of 0.4 μg/m 3 ·passenger. A mass-balance model was developed to estimate the in-carriage PM 2.5 concentration under different driving conditions. [ABSTRACT FROM AUTHOR]

Energy saving and carbon dioxide emission reduction in China is attracting increasing attention worldwide. At present, China is in the phase of rapid urbanization and industrialization, which is characterized by rapid growth of energy consumption. China's transport sector is highly energy-consuming and pollution-intensive. Between 1980 and 2012, the carbon dioxide emissions in China's transport sector increased approximately 9.7 times, with an average annual growth rate of 7.4%. Identifying the driving forces of the increase in carbon dioxide emissions in the transport sector is vital to developing effective environmental policies. This study uses Vector Autoregressive model to analyze the influencing factors of the changes in carbon dioxide emissions in the sector. The results show that energy efficiency plays a dominant role in reducing carbon dioxide emissions. Private vehicles have more impact on emission reduction than cargo turnover due to the surge in private car population and its low energy efficiency. Urbanization also has significant effect on carbon dioxide emissions because of large-scale population movements and the transformation of the industrial structure. These findings are important for the relevant authorities in China in developing appropriate energy policy and planning for the transport sector. [ABSTRACT FROM AUTHOR]

The heavy industry is the main source of CO 2 emissions. Examining the influencing factors of the heavy industry's CO 2 emissions is essential for this industry to achieve a low-carbon transition. Existing research literature often assumes that the relationship between the influencing factors and CO 2 emissions is linear. In fact, most economic phenomena are characterized by fluctuations, due to the influence of business cycles. This often leads to more likely nonlinear relationships between economic variables. This paper uses nonparametric additive regression model to investigate CO 2 emissions from China's heavy industry. The empirical findings show that economic growth, urbanization, and energy efficiency exert a "first promotion, then restriction" inverted "U-shaped" nonlinear effect on CO 2 emissions. To complicate matters further, energy consumption structure and export dependence have an "N-shaped" nonlinear effect on CO 2 emissions. Therefore, in the early stage, the government should actively optimize the industrial structure, strengthen the management of the real estate industry, and expand R&D investment. In the long run, the government should subsidize the heavy industry to expand clean energy consumption, and provide tax incentives to support the export of high-tech industrial products. • This article examines CO 2 emissions in China's heavy industry. • Economic growth exerts an inverted "U-shaped" effect on CO 2 emissions. • Energy consumption structure has an "N-shaped" effect on CO 2 emissions. • Energy efficiency produces an inverted "U-shaped" effect on CO 2 emissions. [ABSTRACT FROM AUTHOR]

• Novel biphasic solvent based on polyamine was developed for CO 2 capture. • Microcalorimetry strategy was used to directly measure the CO 2 absorption heat. • The energy consumption of this absorbent was 32.6 % lower than that of 5 M MEA. • This biphasic solvent has superior phase-splitting behavior. • The salting-out effect was the main reason for the phase-splitting behavior. The CO 2 phase change absorbents(CPCAs) formed by introducing phase-splitting agents have attracted increasing attention because of their great energy-saving potential. However, the volatilization problem of the phase-splitting agents and the high viscosity of the solution affect the application of CPCAs. In this work, a novel CPCAs based on 2-Methylpiperazine (2MPRZ)/H 2 O was established by introducing triethylene glycol monobutyl ether (TGBE) with a high boiling point as a phase-splitting agent, and the 2MPRZ/H 2 O/TGBE system exhibited low volatility and low viscosity. The CO 2 capture performance of the novel CPCAs with different ratios was investigated in this work. The best CO 2 absorption rate was achieved by 2.5 M 2MPRZ/H 2 O/TGBE. The viscosity of this system before and after the CO 2 absorption process was merely 7.68 mPa·s and 11.64 mPa·s, respectively, and no volatilization of the phase-splitting agent was observed simultaneously. A convenient and rapid titration method was employed to determine the distribution of the 2MPRZ products in the two phases, which showed that 98 % of the 2MPRZ products were located in the CO 2 -rich phase. In addition, the CO 2 -rich phase captured 99 % of the total CO 2 , indicating that this system has superior phase-splitting behaviors. The regeneration energy consumption of this biphasic absorbent was 2.59 GJ/t CO 2 , which was 32.6 % lower than that of traditional MEA. Furthermore, the salting-out effect was proved to be the cause of the phase-splitting behavior by 13C NMR analysis. [ABSTRACT FROM AUTHOR]

• Water markedly affected phase change behaviors of anhydrous biphasic absorbents. • The presence of water was negative for CO 2 absorption but beneficial to desorption. • The main CO 2 -product was HCO 3 - in the presence of water rather than carbamate. • Effect of water on CO 2 absorption mechanism of [N 1111 ][Gly]/ethanol was clarified. The ionic liquids (ILs)-based biphasic absorbents are viewed as promising substitutes for CO 2 capture due to their remarkable CO 2 absorption performance, excellent stability and low energy requirement for regeneration. Further decreasing the regeneration heat requirement can be achieved by utilizing ILs-based anhydrous biphasic absorbents, whose solid CO 2 -rich phase contained small volume and low specific heat capacity. Given the high hygroscopicity of ILs and the water present in the flue gas, comprehending the effect of water is crucial for post-combustion carbon capture using ILs-based anhydrous biphasic absorbents. In this work, the effect of water on CO 2 absorption by an anhydrous biphasic absorbent, tetramethylammonium glycinate ([N 1111 ][Gly])/ethanol, was studied. The experimental results demonstrated that the CO 2 loading and absorption rate were decreased in the presence of water, but the CO 2 desorption efficiency was enhanced. Besides, the presence of water slightly reduced the reaction heat of CO 2 absorption by [N 1111 ][Gly]/ethanol to 69.48 kJ/mol CO 2 , which was 20% lower than that of monoethanolamine (MEA) absorbent. Furthermore, the 13C NMR results indicated that the primary CO 2 -product was bicarbonate in the presence of water rather than carbamate. There were three possible pathways for bicarbonate generation: zwitterion hydrolysis, carbamate hydrolysis, and base-catalyzed CO 2 hydration. Water and ethanol competed to react with carbamate. When a large amount of water was present (≥70 wt%), the reaction of ethanol with the carbamate hardly occurred. [ABSTRACT FROM AUTHOR]

The mass transfer performance of CO 2 absorption into blended DEEA/MEA solutions was investigated in a lab-scale absorber packed with Sulzer DX structured packing using a standard orthogonal array with an L 25 (5 6 ) matrix. The volumetric overall mass transfer coefficient (K G a V ) was evaluated at various key operating conditions over a amine concentration range of 2.00–5.00 kmol/m 3 , CO 2 lean loading of 0.15–0.35 mol CO 2 /mol amine, over a wide CO 2 partial pressure range of 6–18 kPa, a liquid feed temperature range of 303.15–343.15 K, with liquid flow rate 3.90–11.70 m 3 /m 2 ·h, and 30.47–47.87 kmol/m 2 ·h inert gas flow rate. The results show that these key operating parameters have significant effects on K G a V . Also, based on orthogonal analysis, it was clear that the order of importance for the contribution to K G a V of the six investigated factors was as follows: CO 2 lean loading > CO 2 partial pressure > Liquid feed temperature > Amine concentration > Liquid flow rate > Inert gas flow rate and the optimization of the experimental combination was B 1 C 1 D 2 A 3 E 3 F 2 . [ABSTRACT FROM AUTHOR]

• Three possible pathways for bicarbonate generation were investigated based on DFT. • Base-catalyzed CO 2 hydration is dominant in [N 1111 ][Gly]/EtOH aqueous system. • Water effect on phase change behavior is analyzed from hydrogen bonding view. • Water content of 5 wt% promotes products aggregation in favor of phase change. Ionic liquids-based anhydrous biphasic absorbents have the potential to lower the energy consumption for CO 2 capture. Recent experimental studies have revealed that the presence of water in [N 1111 ][Gly]/EtOH system leads to generation of a new CO 2 -product – bicarbonate and affects the phase change behavior. However, the reaction pathway for bicarbonate formation remains unclear. In this work, the reaction pathways were investigated in depth through quantum chemical calculations employing density functional theory, with reaction rate constants determined via transition state theory. Among the three possible reaction pathways, the base-catalyzed CO 2 hydration reaction prevailed, i.e. a one-step reaction involving [Gly]-, H 2 O, and CO 2. An H atom in H 2 O was transferred to [Gly]-'s amino group, forming protonated [Gly]-, and hydroxide combined with CO 2 to generate bicarbonate. Additionally, molecular dynamics simulations were conducted to understand the phase change behaviors with varying water content. When water content exceeded 5 wt%, an increased water content led to reduced hydrogen bonding among products and enhanced hydrogen bonding of products-solvent with the solvent, diminishing product self-aggregation. No phase change behavior were observed at water contents up to 80 wt%. This study could well explain the experimental phenomena of water effect on CO 2 absorption in [N 1111 ][Gly]/EtOH, providing theoretical references for application of ILs-based anhydrous biphasic absorbent. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mo-based MXene is first applied as a cathode catalyst for Li-CO 2 batteries. • An innovative surface modification strategy, mild oxidation by CO 2 , is employed. • The catalyst optimizes the growth and decomposition of discharge products. • This MoO 2 @Mo 2 C-based Li-CO 2 battery outperforms most other MXene-based catalysts. The lithium-carbon dioxide (Li-CO 2) batteries hold promise for energy storage, given their capacity to capture and convert carbon dioxide (CO 2). However, the practical application of Li-CO 2 batteries continues to face substantial obstacles caused by sluggish CO 2 reduction/evolution kinetics, resulting in high overpotential and short lifespan. This work presents the fabrication of a highly effective MoO 2 @Mo 2 C heterostructure hybrid catalyst using a CO 2 oxidation strategy. This strategy integrated (in-situ) MoO 2 onto the surface of two-dimensional (2D) Mo 2 C MXene, enhancing catalytic activity while preserving 2D electron/ion pathways. As a result, the MoO 2 @Mo 2 C, when used as a catalyst in Li-CO 2 battery showcased a discharge capacity of 20790.8 mAh g−1 at a current density of 200 mA g−1. Notably, it achieved a long cycling life of 230 cycles at a cutoff capacity of 1000 mAh g−1 with a voltage gap as low as 1.85 V, which was significantly superior to that of a pristine Mo 2 CT x catalyst (3.61 V after twenty cycles). This work provides critical insights into the design of MXenes-based high-performance catalysts for advanced Li-CO 2 batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel cerium-based MOFs crystal with pyrene-based organic structure is obtained by solvothermal treatment firstly. • The high efficiency of charge separation and transfer can realize the collaborative improvement of redox activity. • A π-conjugated construction is beneficial for the generation of electronic localization as well abundant superoxide radicals. A novel cerium-based metal–organic framework crystal (Ce-TBAPy) was developed via a one-pot solvothermal method. Interestingly, the Ce-TBAPy photocatalyst material demonstrated an enhanced collaborative photoredox performance in terms of acetaldehyde degradation and water reduction, and the photoreaction rates of Ce-TBAPy shown about 5.06-times and 3.94-times higher, respectively, than those when untreated H 4 TBAPy was used. A significant finding is that the apparent quantum efficiency value of Ce-TBAPy for CO 2 generation from CH 3 CHO decomposition performs 5.12% at 420 nm. The accumulation of abundant separated holes on the pyrene macrocycles could oxidize CH 3 CHO to CO 2 easily. Meanwhile, cerium integration with TBAPy4− ligands to form a π-conjugated construction further resulted in sufficient photoinduced electrons and exhibited effective interfacial charge separation, which harvesting the reduction of H 2 O to H 2 efficiently. The electronic localization influence arising from the formation of –COO-Ce functional groups in Ce-TBAPy and the direction of electron migration in the photocatalytic system were further confirmed by DFT calculation. This work provides an effective strategy to obtain rare earth-based MOF photocatalysts with dual redox functions and holds promise for advancing the prospect of using MOF materials to convert solar energy into chemical energy. [ABSTRACT FROM AUTHOR]

Based on China's 30 provinces penal data, from 1990 to 2017, this paper uses the quantile regression model to estimate the impact of fossil energy abundance and clean energy abundance on economic growth and carbon dioxide (CO 2) emissions. The findings show that fossil energy abundance exerts a greater impact on economic growth in the intermediate quantile provinces such as Hebei, Jilin, Liaoning, and Shandong because these provinces have larger petroleum processing and coal gas production industries. The CO 2 emissions in the upper 90th quantile provinces such as Liaoning, Shanxi, and Shandong, receive the biggest impact from fossil energy abundance because these provinces consume more coal and oil. However, the impacts of renewable energy abundance on economic growth in the 50th-75th, upper 90th, and 75th-90th quantile groups are greater, since their renewable energy industry is growing faster. The influence of renewable energy abundance on CO 2 emissions in all quantile groups is positive, meaning it does not play a prominent role in mitigating CO 2 emissions. Therefore, each quantile province should formulate specific policies to promote the growth of renewable energy and actively develop strategic emerging industries. • Fossil energy contributes more to economic growth in the middle-level quantiles. • The impact of fossil energy on emissions in the upper 90th quantiles is the strongest. • Renewable energy abundance does not play a prominent role in reducing emissions. [ABSTRACT FROM AUTHOR]

Conventional wisdom advises keeping windows and doors closed in air-conditioned or mechanically-ventilated space. However, this guideline often proves challenging in high-occupancy offices, where the constant influx and egress of individuals, coupled with a strong inclination toward open windows, trigger occupant-induced ventilation (OV) that can affect indoor air quality (IAQ) and energy consumption. To address this, we explored using portable air cleaners (PACs) as a cost-effective ventilation strategy to replace mechanical ventilation (MV) while maintaining IAQ and respecting occupant freedom. We conducted a single-blind trial in a 100 m2 office in Shanghai from December 2020 to March 2021, measuring 857 h of indoor and outdoor temperatures, CO 2 and PM 2.5 concentrations, and occupant behaviors. We obtained 618 valid subjective responses and conducted a 14-day test to measure possible by-products, such as O 3 , formaldehyde, and VOCs, during the operation of PACs. The results showed that, first, although MV achieved 2–3 times higher air change rates than PACs, indoor CO 2 concentrations remained below 1000 ppm, the commonly accepted threshold, using PACs in the presence of OV. Second, PACs effectively reduced PM 2.5 levels during outdoor PM 2.5 peaks. Third, occupants' perceived IAQ did not differ between the use of PACs and MV (p >0.05), although individuals with PACs in the afternoon reported slightly increased sleepiness (p <0.05). Fourth, in the presence of OV, PACs demonstrated significant energy-saving potential in improving IAQ. Our study showed PACs can be a cost-effective method to replace MV while maintaining IAQ and preserving occupant freedom. • Deploy portable air cleaners (PACs), enabling window and door opening by occupants. • A randomized, single-blind trial was conducted for two winters in an open office. • PACs can control indoor PM 2.5 in the presence of occupant-induced ventilation (OV). • Indoor CO 2 concentrations remained below 1000 ppm using PACs due to OV. • Measurements confirmed low risks associated with by-products of PACs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Excellent activity and selectivity of CO 2 -to-CH 4 conversion is realized by MIS. • The ultrathin insulator layer significantly expedites the interfacial electrons tunneling. • The MIS promotes rate-determining step from *COOH to *CO to produce CH 4. A metal–insulator-semiconductor (MIS) ternary photo-system was intricately crafted through precise amalgamation polyvinylpyrrolidone (PVP)-capped metal Cu with typical covalent triazine framework CTF-1 via electrostatic self-assembly. The 2 % Cu-PVP-CTF exhibited an impressive CH 4 yield of 80.7 μmol·g−1·h−1 with selectivity of 96.8 % under visible light, representing a 2.3-fold and 112-fold improvement over Schottky-type Cu-CTF and pristine CTF-1, respectively. In-situ XPS and VASP-diff calculations unfolded that the ultrathin PVP insulating layer significantly expedited interfacial charges tunneling, corroborated by smaller lifetime τ 2 determined via femtosecond transient absorption spectroscopy. The intermediates of paramount importance in CO 2 reduction like *COOH and *HCHO were meticulously monitored by in-situ Fourier infrared spectroscopy. DFT calculations elucidated that Cu-PVP-CTF was notably more adept at facillitating the rate-determining step (*COOH → *CO) to produce CH 4 than Cu-CTF. This work tamps the groundwork for conceptional roadmap in designing novel MIS photo-system for CO 2 conversion. [ABSTRACT FROM AUTHOR]

Converting CO 2 into carbon-based fuels via the photoelectrochemical (PEC) approach is considered as an one-stone-two-birds strategy for alleviating the greenhouse effect and energy crisis. Here, we report a novel two-step strategy to integrate uniform Au NPs with controllable Au(111)/Au(200) boundaries on p-Si photocathodes for efficient and selective PEC CO 2 conversion to CO. Theoretical calculations suggest that the Au(111)/Au(200) boundaries significantly reduce the energy barrier for forming the *COOH intermediate during CO 2 reduction. Moreover, we discover that embedding the Au NPs into Si surface can not only further improve the PEC activity and selectivity but also significantly boost the operational stability of Si photocathodes, because of the ameliorated interfacial contact between the Au NPs and Si substrate. Eventually, the optimized Au/p-Si photocathode demonstrates a great CO selectivity of 82.2 % and an impressive operational stability of over one week, which offers critical insights into the design of photocathodes for solar fuel production. [Display omitted] • Uniform Au NPs with controllable Au(111)/Au(200) boundaries were successfully integrated on p-Si photocathodes. • Au(111)/Au(200) boundaries significantly reduce the energy barrier for forming the *COOH intermediate • Embedding the Au NPs into Si surface can boost the operational stability of Si photocathodes • A great CO selectivity of 82.2 % and stability of over one week outperforms almost all the Si based photoanodes [ABSTRACT FROM AUTHOR]

The most critical challenge in the noodle industry is ensuring the development of various high-quality products. Dough mixing is a very important initial stage in the development of noodles, which has a major impact on the preparation and quality of the noodles. The mixing process helps to form a dough as a single homogenous substance and develops certain rheological characteristics that provide the optimum flow of all technical processes in the next production stages. The mixing process is impacted by the raw and auxiliary materials used (the quality of flour, the amount of water added, the amount of salt and alkali added), the performance of the mixing equipment, and the mixing process parameters (mixing time, mixing speed, water addition, water temperature, and dough temperature). Proper management of the mixing process and implementation of enhancement techniques can greatly improve the dough rheology and noodle quality. This review paper describes the available mixing information and details the influence of various mixing characteristics on dough rheology and noodle quality. Techniques to improve the mixing process and equipment are provided. • Mixing process results on dough rheology and noodle quality were reviewed. • The addition of CO 2 snow during mixing maintained the dough's low temperature. • The dough obtained by adding water in stages was superior to adding water one time. • Vacuum mixer enhanced mixing performance and compactness of the dough structure. • Mixing enhancements must start with proper management of main parameters. [ABSTRACT FROM AUTHOR]

Transition metal boride enable applications in fields of cutting tools as the hard phase, but their fabrication suffers from shortcomings in high temperature for binary and hard/soft phase balance. Here, we leveraged a WCoB-Co cermets prepared by using elemental powders of W, Co and B powders via in situ synthesis method and investigated the microstructure evolution of a composite structure of WCoB/Co. The phase evolution, microstructure evolution and mechanical properties were investigated using X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS). The complete sintering process consist of three solid-phase reaction stages and one liquid-phase sintering stage. The solid-phase reaction stage includes the following three reactions: B + 2Co → Co 2 B, 11 W +15 Co 2 B → 9WCoB + W 2 Co 21 B 6 , and 14 W + 2W 2 Co 21 B 6 → 12WCoB + 23Co + Co 7 W 6. The eutectic liquid phase, essential for the densification, forms at 1323 °C. The Rockwell hardness and density value reach 87.5HRA and 12.11 g/cm3, respectively. At 1380 °C, the traverse rupture strength (TRS) reaches the peak value of 1495 MPa. Moreover, the results show that transgranular fracture is the main fracture mode. The densification stage was completed at ~1400 °C. In particular, Co 7 W 6 phase was discovered during the study of the evolution of WCoB-Co cermets. An increase of the B content was found to be beneficial to eliminate the Co 7 W 6 phase that proved to be detrimental to mechanical properties. • WCoB-Co cermets were prepared using elemental powders. • The paper focuses on phase evolution and microstructure evolution. • Increasing the content of B element can improve the mechanical properties and eliminate Co 7 W 6 phase. [ABSTRACT FROM AUTHOR]