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Traditionally, cellulose nanofiber (CNF) production has primarily relied on virgin cellulose sources. Yet, the shift to using paper mill sludge (PMS) as a source for CNF underscores the significance of reusing and recycling industrial byproducts. PMS contains significant amounts of cellulose that can be extracted as a raw material. The purpose of present study is to provide a sustainable approach to PMS utilization as a paper coating additive in the cellulose nanofibrils (CNFPMS) form via simply scalable wire-wound rod coating method. The effect of CNFPMS additive amounts at two coating layers on microstructure and surface properties of coatings such as porosity, air permeability surface roughness and optical properties such as brightness, gloss and CIE L*a*b* is studied, which they can also provide insight for the eventual print performance. Results indicated that the obtained CNFPMS in paper coating shows 52% decrease in porosity, presenting significant improvement in the coating microstructure. The marginal increase in permeability coefficient and surface roughness, 54% and 10%, respectively, suggests improving color reproduction and preventing color density losses. Optical analysis showed slight decrease in brightness and gloss, as was expected. Notably, the lightness was improved, which also indicates increasing color gamut volume in printing applications. As a result, the current work offers a sustainable approach to manage PMS for use in paper coatings as a high-value-added material. [ABSTRACT FROM AUTHOR]

Paper-based electrochemical sensors provide the opportunity for low-cost, portable and environmentally friendly single-use chemical analysis and there are various reports of surface-functionalized paper electrodes. Here we report a composite paper electrode that is fabricated through designed papermaking using cellulose, carbon fibers (CF), and graphene oxide (GO). The composite paper has well-controlled structure, stable, and repeatable properties, and offers the electrocatalytic activities for sensitive and selective chemical detection. We demonstrate that this CF/GO/cellulose composite paper can be reduced electrochemically using relatively mild conditions and this GO reduction confers electrocatalytic properties to the composite paper. Finally, we demonstrate that this composite paper offers sensing performance (sensitivity and selectivity) comparable to, or better than, paper-based sensors prepared by small-batch surface-modification (e.g., printing) methods. We envision this coupling of industrialized papermaking technologies with interfacial engineering and electrochemical reduction can provide a platform for single-use and portable chemical detection for a wide range of applications. [ABSTRACT FROM AUTHOR]

A high-performance electromagnetic interference (EMI) shielding material based on carbon nanofiber (CNF) and cellulose filter (CF) paper has been fabricated by a cost-efficient and convenient dip-coating method. The EMI shielding performance of the CF papers with micron level thickness tolerance (2.5-12.7 µm) have been explored by considering the microstructure, serviceability, electrical conductivity, and number of dip-coating cycles. Field emission scanning electron microscopy of the surface and edge of the composites support the good electrical conductivity, which showed distinct increment in electrical conductivity from 6.6 × 10 to 0.85 S/cm. The number of dip-coating cycles have a significant impact on electrical conductivity, and this has also been studied and inferred after alteration of dipping cycles. The electromagnetic shielding efficiency of CNF-coated CF paper exhibits 24.6 dB with only 25 dip coating cycles. Moreover, from commercially viable points of view, extensive study has been executed to investigate CNF-coated CF papers in the simulated ageing environments viz. water, thermal ageing, and thermo-degradability over a wide range of temperature (ambient to 600 °C). All the environmental factors have been simulated on a laboratory scale. The CNF-coated CF papers possess significantly higher mechanical properties than pure CF paper. This type of conductive CNF-coated CF paper is a promising candidate to be used as highly flexible, lightweight, and cost-efficient EMI shielding material in advanced multifunctional application areas. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate how a wide range (10–100%) of cellulose nanofiber (CNF) addition affects the mechanical properties of paper sheets. Young's modulus and tensile strength in the dry and wet states were measured and compared. In the dry state, the Young's modulus increased with the increase of CNF addition. However, the dry specific Young's modulus was constant for all CNF additions, which was one interesting result. The tensile strength increased as the CNF addition increased to 70%; however, there was no further improvement when the CNF addition was greater than 70%, which was another interesting finding. In the wet state, although the Young's modulus decreased when the CNF addition was greater than 20%, the wet tensile strength of the sheets increased almost linearly with increasing CNF addition up to 50%, followed by a slight decline. The maximum wet strength retention reached nearly 10% with 40% CNF addition, despite the higher water uptake (108%). One of advantages of utilizing CNFs as reinforcement agent in paper is that they can improve the wet strength while making paper sheets maintain a higher moisture content. [ABSTRACT FROM AUTHOR]

Patients with hypertension are seriously affected by Parkinson's disease than patients with normal blood pressure. Thus, early detection of hypertension and Parkinson disease by monitoring subtle changes in specific biomarkers from body fluids can minimize the risk. This paper proposes a flexible, portable paper-based sensor for simultaneous electrochemical sensing of dopamine and uric acid, using differential pulse voltammetry and electrochemical impedance spectroscopy on electrodeposited Prussian blue on carbon dots@graphite paper. The characteristic peaks of dopamine and uric acid in the differential pulse voltammogram are well separated. Further surface characterization of Prussian blue/carbon dots@graphite paper was carried out by Raman Spectra and Scanning Electron Microscope (SEM). The proposed sensor promoted the fast electrochemical detection of dopamine and uric acid with the linear response for concentrations from 0.2–920.0 μM with a limit of detection 0.015 μM, respectively in an aqueous sample. Excellent flexing stability is demonstrated by the proposed sensor, which can maintain its initial current after being bent more than 300 times. [ABSTRACT FROM AUTHOR]

The production of high filler-loaded recycled papers is often affected by high values of linting and low values of strength. In the first case, the accumulation of lint particles from paper’s surface on the printing blanket affects the quality of the printed paper and the pressroom’s productivity. In the second case, increasing the use of fillers and recycling cycles lead to poor paper strength. Cellulose nanofibers (CNFs) are receiving a great deal of attention due to their potential as a reinforcement aid for high filler-loaded papers through filler–fiber interaction and interfiber bonding. It is already proven that high quality CNFs can reduce linting, although their industrial application is limited by their high production cost. The objective of this research is, therefore, to quantify the effect of applying lower grade, more sustainable CNFs on linting phenomena and on the mechanical properties of recycled papers. Eucalyptus, pine and triticale residues were used as cellulose sources, and the CNFs were produced minimizing the chemical pretreatment before homogenization. Addition of 3 wt% of CNFs from pine residues into the recycled paper with 15.7 wt% of total filler reduced linting by 40% and increased tensile strength by 15.1%; further improvements on linting and mechanical properties were achieved at 5 wt%. Moreover, the increase in drainage time can be overcome by the addition of a retention aid, in this case a coagulant-cationic polyacrylamide-bentonite system, commonly used in paper mills. [ABSTRACT FROM AUTHOR]

The microencapsulation of flame retardants can avoid the problems of water absorption and loss. In this paper, hydrophobic microcapsule-encapsulated ammonium polyphosphate (HMAPP) was prepared by ion exchange and Stöber method and applied to the preparation of hydrophobic flame-retardant kraft paper by impregnation. The microscopic morphology and element analysis of the hydrophobic microcapsules tested by TEM and SEM showed that nano-scale particles with a size of about 100 nm have been successfully prepared, and the core–shell structure has been formed. HMAPP constructed a rough structure with low surface energy on the surface of kraft paper and provided the kraft paper with hydrophobic property. The water contact angle of kraft paper reached 122.7 ° after treated by HMAPP, while it also enhanced the physical strength of the paper. Kraft had the self-extinguishing phenomenon after treated by HMAPP, which attached to the surface of kraft paper were heated and melted to release ammonia to dilute combustible gas and oxygen, and formed a flame-retardant layer containing SiO2 particles, phosphoric acid, metaphosphoric acid, pyrophosphoric acid, and carbon flakes on the fiber surface. There were C–C, C–O–C bonds in the carbon layer after flame-retardant treatment, indicating that the pentose contained in fiber has not been completely destroyed. In addition, the presence of Si and P elements in the residual carbon indicates that the decomposed flame retardant adheres to the surface of the fiber to block the heat transfer and flame spread. [ABSTRACT FROM AUTHOR]

Increasingly popularity of electronic devices and wireless apparatus requires advanced materials to cope with severe electromagnetic wave pollution. Herein, magnetic EM wave shielding material, Ti3C2Tx/Fe3O4/aramid nanofibers composite paper, composed of low-dimensional Ti3C2Tx flakes and carboxylation Fe3O4 nanoparticles, was developed via vacuum-assisted filtration. At the meanwhile, uniform dispersion of components was achieved to overcome magnetic through ingenious electrostatic force regulation originated from negative functional groups. The Ti3C2Tx/Fe3O4/aramid nanofibers composite paper exhibited suitable magnetic performance, outstanding electrical conductivity, and excellent electromagnetic interference shielding performance. Moreover, the Ti3C2Tx/Fe3O4/aramid nanofibers composite paper demonstrated favorable mechanical properties, whose tensile strength and Young's modulus reached 132.2 ± 2.1 MPa and 5.23 ± 0.14 GPa, respectively. The combination of electromagnetic shielding capacity (derived from Ti3C2Tx flakes, carboxylation Fe3O4 nanoparticles) and mechanical properties (derived from aramid nanofibers) provided feasible strategy in fabricating advanced EMI shielding composite with astonishing comprehensive performance. [ABSTRACT FROM AUTHOR]

A composite formed of NiO nanoflakes assembled on carbonized filter paper (CFP) has been successfully synthesized by a hydrothermal route with subsequent annealing. The CFP substrate presented a three-dimensional (3D) network structure. The composite electrode demonstrated high capacity and good cyclic and rate capabilities. It delivered a capacity of 724 mA h g−1 at current density of 100 mA g−1 after 100 cycles without apparent capacity fading during cycling. It delivered a capacity of 446 mA h g−1 even at high current density of 1000 mA g−1. The composite achieves better battery performance through ZnCl2 activation compared with conventional HNO3 activation. [ABSTRACT FROM AUTHOR]

Importantly, trends and developments of this interaction found in both biosensors and bioassays have opened new perspectives in the sensing field and are therefore also of great interest to the sensor community. (i) Biosensors are chemical sensors in which the recognition system utilizes a biochemical mechanism for the interaction process in/at the recognition layer. [Extracted from the article]

In response to food packaging improvements, this study investigates changes in mechanical and thermal barrier properties of pigment-based paper coatings when cellulose nanocrystals (CNC) and cellulose nanofibers (CNF) are added to the formulation. Stable dispersions of all coating components were formed between pH 7–9 (zeta potential > |30 mV|) except CNF, which favored stable dispersions at higher pH. Hydrodynamic diameters (Dh) of CNC and CNF decreased when interacting with calcium carbonate ions (Ca2+ and CO32-); however, latex binder and dispersant diameters were unaffected by the presence of CaCO3 in solution. Thermal barrier performance was quantified by measuring ΔT across coated samples, with and without nanoparticle additives. Both CNC and CNF additives significantly contributed to the ΔT measured, with the best result recorded for 2 wt% CNF, pH 7, and a drying rate of 25 °C/min. This sample recorded 37 ± 6 °C higher than the ΔT for baseline coatings (without additive). Dynamic mechanical analysis (DMA) showed a higher storage modulus for all samples containing CNC and/or CNF compared with the baseline coating, suggesting a material with greater resistance to deformation from applied load. Higher dissipation energy was also observed; however, lower tan delta values suggest improved mechanical properties with both additives. [ABSTRACT FROM AUTHOR]

Carbonization of biomasses is an effective and important approach to recycle biomass waste. The tissue papers are one of the most common household trash and waste lots of natural resources and energies. Herein, the one-step carbonization and activation treatment was applied on two kinds of tissue papers to transform them into porous carbons. It was found the precursor structure and composition as well as the calcination temperatures play key roles to control the pore structures. As the active materials of supercapacitor electrodes, the resultant porous carbons obtained from different paper precursors and calcination temperatures (700–900 °C) presented different electrochemical performances. The microporous carbons derived from the 700 °C calcination of the tissue paper using the wood pulp as the raw material showed high capacitance up to ~ 200 F/g, providing a simple but effective way to recycle biomasses. [ABSTRACT FROM AUTHOR]

A novel cellulose substance (ordinary laboratory filter paper) derived hierarchical carbon/tin-oxide/molybdenum-dioxide (carbon@SnO2@MoO2) ternary nanoarchitectonic was fabricated by the self-assembly process and subsequent carbonization treatment. The resultant nanocomposite was composed of thin tin oxide layer sandwiched between the porous carbon nanofibers and the external molybdenum dioxide coating layer, where the thickness of the molybdenum dioxide coating layer was controlled facilely. As being utilized as an anodic material for lithium-ion batteries, the nanocomposite displayed high reversible capacity and good rate performance that are superior to those of the carbon@MoO2 hybrid without SnO2. The good electrochemical performance of the anode was benefited from the sophisticated multi-level structures of the composite, small sizes of the tin oxide (ca. 5 nm) and molybdenum dioxide (ca. 6 nm) nanocrystallites contained therein, and the synergistic interactions between the tin oxide layer, the outer molybdenum dioxide coating layers, as well as the porous carbon buffering matrix. For such a composite with MoO2 and SnO2 contents of 20 and 10%, respectively, by weight, it delivered a specific capacity of 608.1 mAh g−1 after 100 discharge/charge cycles at the current rate of 100 mA g−1. The current work presents a facile and cost-effective pathway to synthesize bio-substance derived nanocomposite materials for energy applications. [ABSTRACT FROM AUTHOR]

Entire carbon nanofiber mats (carbon nanofiber paper) based on polyacrylonitrile pyropolymer composite were prepared by the preliminary oxidation (stabilization) of the initial polymer at 250-350°C in air and following pyrolysis at 800-1200°C under vacuum. The mats were tested as cathodes in a fuel cell on polybenzimidazole membrane. Properties of the pyropolymers which were obtained by polymer carbonization could be significantly changed by the addition of specific additives to polyacrylonitrile and also by changing thermal treatment. Particularly, the addition of Ketjen Black® or Vulcan® XC72 carbon blacks and polyvinyl pyrrolidone during electrospinning step resulted in increase of material electrical conductivity and inner porosity, which is important for improving fuel cell performance. Depending on oxidation and pyrolysis temperature, the physical properties of platinated carbon nanofiber paper and the efficiency of a fuel cell on polybenzimidazole membrane significantly change. [ABSTRACT FROM AUTHOR]

In the recent years, several methods for producing cellulose nanofibers (CNF) have appeared. Depending on the type of treatment and its conditions, the source of cellulose and the fibrillation method, different properties and characteristics can be obtained. TEMPO-mediated oxidation has been extensively used for CNF production and it is considered as one of the most suitable treatments to obtain high-performance CNF with superior properties and reduced size. However, the recovery of the catalyst and its cost is still a challenge. In the recent years, the oxidation by means of ammonium persulfate (APS) has appeared as a potential alternative, although it is commonly used for cellulose nanocrystals production. The present work aims at comparing the properties of CNF obtained by means of TEMPO-mediated oxidation (TOCNF) and ammonium persulfate oxidation (APSCNF). For this, a similar oxidation degree was selected, adjusting the treatment conditions of both oxidative methods. The obtained results exhibited that similar properties can be obtained with different production costs associated. In addition, the APSCNF exhibited a significantly lower degree of polymerization and slightly higher transmittance, indicating the presence of higher crystalline regions. Finally, both types of CNF were tested over a recycled paper substrate, revealing that both APSCNF and TOCNF significantly increased the mechanical properties of paper with low effect on pulp drainability, representing a great advantage for the paper industry. [ABSTRACT FROM AUTHOR]

This paper adopts the "baseline scenario method" to construct a comprehensive model for calculating and reducing carbon emissions generated by employee travel, including the accounting of carbon emissions from commuting and business travel, as well as the assessment of green travel for carbon reduction. The study employs methods such as questionnaires and on-site interviews to collect travel data from employees of a research institute in Beijing as a case study. The results show that employees' commuting methods are diverse, with the subway being the primary mode of travel; however, business travel generates higher carbon emissions, particularly among employees with higher education levels. The research concludes that the model proposed in this paper provides a framework for preliminary carbon emission estimation, but to improve the accuracy of the estimates, more variables and factors need to be considered, and the limitations of the model are pointed out. The research findings have significant implications for policy and institutional practices, suggesting the adoption of more targeted measures to reduce the use of high-carbon-emission travel methods and to encourage the use of green travel options. With the continuous advancement of data collection technologies in the future, it will be possible to further establish a more refined carbon emission accounting model and obtain more accurate and comprehensive travel data, thereby providing solid data support for the development of more effective carbon reduction strategies and policies. [ABSTRACT FROM AUTHOR]

This paper investigates how National Eco-industrial Demonstration Parks (NEDP) in China affects carbon emission efficiency. The difference-in-differences (DID) strategy is used for analysis. This paper finds that the construction of NEDP is conducive to the improvement of carbon emission efficiency, and the findings remain robust through placebo tests and propensity score matching. Heterogeneity analysis shows NEDP construction has greater utility on carbon efficiency in non-resource-based cities as well as in environmentally friendly cities. The mechanism analysis found that green technology innovation, industrial restructuring, and the relocation of industrial enterprises are effective ways to improve carbon efficiency in NEDP. Finally, this paper finds that the construction of NEDP has obvious spatial spillover effects on carbon efficiency, which can effectively heighten the carbon efficiency level of this locality and nearby areas. [ABSTRACT FROM AUTHOR]

The marine ecological compensation (MEC) policy is a scheme for protecting and restoring marine ecology. The previous studies have verified that the policy has improved the marine environment, ignoring the comprehensive performance of the economy and environment. Is the MEC policy actually effective for reducing marine carbon emission considering resource input and economy output? To address the question, this paper evaluates the impact of MEC policy on marine carbon emission efficiency by introducing the multi-stage difference-in-difference with propensity score matching. The results show that the MEC policy significantly improves marine carbon emission efficiency, and the positive effects dynamically enhance over time. Low-carbon technology innovation is confirmed to play a mediating role by which the MEC policy improves marine carbon emission efficiency. Therefore, gradually popularizing the MEC policy and accelerating low-carbon technology innovation are crucial measures to improve marine carbon emission efficiency and achieve sustainable marine development. [ABSTRACT FROM AUTHOR]

Four-layer multiwalled carbon nanotube (MWNT) thin films were deposited via dropcasting (1 mg/mL MWNTs and 10 mg/mL SDBS) onto filter papers that vary in pore size (1, 5, 25, and 40 µm) to determine the effect of the underlying substrate structure on the in-plane properties of the films. The films (<100 nm thick) were dried using vacuum filtration, and drying in a 65 °C heater with and without a ceramic heating board. DC resistance of the films ranged from 6 × 103 to 9.3 × 109 Ω. Impedance spectroscopy analysis revealed a low and a high frequency inductive response and two parallel R–C circuits for the more conducting thin films. High resistance films were fit by a single RC circuit with a constant-phase element. The differences in the in-plane electrical responses of the different MWNT films can be explained by the degree of carbon nanotube surface coverage, obtained as a result of using different pore size filter papers. The drying method utilized also affected the CNT network formation and its resultant electrical properties. [ABSTRACT FROM AUTHOR]

The carbon emission trading pilot policy is an important initiative to achieve synergistic economic-environmental development. Based on the data of 268 cities in China from 2006 to 2020, this paper analyzes the impact of carbon emission trading pilot policy on urban innovation capacity by using a time-varying difference-in-difference model. The study shows that, first, the implementation of the CETP improves the innovation capacity of cities, and the robustness test confirms the above findings. Second, the effect of the policy on enhancing urban innovation capacity is heterogeneous between the type of innovation and city type: the promotion of innovation capacity is stronger for utility model patents and non-capital cities. Third, there is a positive spillover effect of the implementation of the CETP on the promotion effect of the urban innovation capacity, which can lead to the improvement of the innovation capacity of neighboring cities. This paper has some reference value for building a unified carbon emission trading market and promoting low-carbon economic development within China. [ABSTRACT FROM AUTHOR]

An effective and just industrial transition is necessary both to mitigate climate change and protect jobs, and as a precursor to enable other sectors to decarbonise. Activity is at an early stage and examples of successful sector-wide interventions to decarbonise industry do not yet exist. Governments of industrialised countries are beginning to develop policy and provide funding to support deployment of carbon capture and low-carbon hydrogen infrastructures into high-emitting industrial clusters, but options for sites outside of clusters, denoted here as 'dispersed sites', are also required. This paper takes a mixed methods approach to provide the first analysis of the issues facing dispersed industrial sites on their route to decarbonisation and to suggest solutions to the challenges they face. Using the UK as a case study, it first characterises dispersed sites in terms of location, emissions released, sectors involved, and size of companies affected. It then shows how these features mean that simply expanding the geographical scope of the present UK decarbonisation strategy, which focuses on the provision of carbon capture and low-carbon hydrogen, would face a number of challenges and so will need to be broadened to include a wider range of abatement options and other considerations to meet the needs of dispersed sites. While the solutions for each place will be different, these are likely to include some combination of the expansion of shared infrastructure, the development of local zero-carbon hubs, research into a wider range of novel abatement technologies and facilitating local participation in energy planning. The paper concludes with a discussion of remaining knowledge gaps before outlining how its findings might apply to industrial decarbonisation strategies in other countries. [ABSTRACT FROM AUTHOR]

The construction of high-speed railways and the smart city pilot (HSR-SCP) demonstrates the synergy of traditional and new infrastructure upgrades, which has a significant influence on the economic transition and green economic growth. However, little study has been conducted on the impact of HSR-SCP synergy on carbon emissions. Applying China's prefecture-level panel data, this paper, therefore, attempts to investigate the effect of HSR-SCP on carbon emissions and uncover its in-depth mechanism through the multi-period difference-in-differences model. Notably, an appropriate instrumental variable for HSR-SCP is introduced to address possible endogeneity. The main conclusions indicate that the construction of HSR-SCP plays an essential role in cutting carbon emissions, which is still valid after adopting the instrumental variable method and some robustness tests. Furthermore, green technology innovation plays a crucial intermediary role in that relationship. Finally, the carbon reduction effect of HSR-SCP is significant in Mid-Eastern China and cities with high population sizes and administrative levels, but not in other cities or regions. The research conclusions demonstrate the significant synergy of traditional and new infrastructure upgrades on carbon reduction and provide an empirical foundation for developing countries to realize low-carbon development through optimizing smart infrastructure and promoting green technology innovation. [ABSTRACT FROM AUTHOR]

How the transformation of trade patterns affects carbon emissions is an important topic in the field of trade and the environment. Based on the panel data of Chinese cities from 2000 to 2016, this paper uses fixed effect model, instrumental variable model and threshold estimation model to investigate the impact of the transformation of export trade patterns on carbon emissions and its internal mechanism. We find that during the investigation period, the transformation of export trade pattern has a significant "U"-shaped nonlinear impact on carbon emissions, and the research results still hold after a series of robustness checks and instrumental variable estimation; through the mechanism analysis of the threshold effect, it is found that in the process of the impact of trade patterns transformation on carbon emissions, there are double thresholds for energy structure transition; the nonlinear impact of export trade pattern transformation on carbon emissions has significant heterogeneity in different regions, city categories, and different periods; the mechanism analysis results show that industrial structure upgrading, industrial co-agglomeration, and green technology innovation are the main paths that the transformation of export trade patterns affects carbon emissions. Under the dual goals of fulfilling China's commitment to "carbon peak in 2030 and carbon neutrality in 2060" and implementing corporate social governance to promote green and sustainable development, this paper will provide suggestions for realizing the goal of low-carbon emission reduction from the perspective of the transformation of export trade patterns. [ABSTRACT FROM AUTHOR]

This paper examines whether financial technology (FinTech) development affect household energy consumption. The proposed point that FinTech can reduce household energy consumption is theoretically discussed and empirically tested using data from the 2017 Digital Financial Inclusion Index, the 2018 China Family Panel Studies (CFPS), the 2018 China Environmental Statistical Yearbook and the 2018 China Science and Technology Statistical Yearbook. The results show that FinTech contributes to reducing household energy consumption. Several retests, including the instrumental variable, replacement sample and propensity score matching methods, prove its robustness. Mechanism tests show that investment in environmental governance and technological innovation promotion are the two main transmission channels. We also find that the reducing effect is more significant in the following groups: the low-middle income level classes, the eastern regional residents, those with bachelor's degrees and above, the those aged over 60 and rural residents. The outcomes of this paper call for government departments to positively guide FinTech development to reduce household energy consumption. From another perspective, the conclusions drawn from our analysis make a great reference value for countries and provide new ideas for Chinese carbon peaking and carbon neutralisation goals. [ABSTRACT FROM AUTHOR]

Whether the market-based environmental regulation policy can achieve a win–win situation of economic growth and carbon emission reduction has always been an academic controversial topic. Taking the pilot policy of energy-consuming right trading (ECRT) of China in 2016 as a quasi-natural experiment, this paper uses the difference-in-differences (DID) method to investigate the policy impact of ECRT on the economic performance and carbon emissions of firms. An economy-environment composite index has been conducted for testing double dividend effect of ECRT. The empirical results show that ECRT can improve the economic performance and reduce carbon emissions of firms significantly. The double dividend effect is more significant in high-carbon emission firms, non-state-owned firms and prior to COVID-19 pandemic. ECRT policy has Porter innovation mechanism, in which innovation input is the main contribution of economic dividend effect and green technology innovation is the main contribution of environmental dividend effect. The conclusions of this paper provide empirical evidence and policy implications for realizing the common development of economy and environment, accelerating the process of emission reduction and building a national energy trading market. [ABSTRACT FROM AUTHOR]

The impact of the carbon emission trading system (ETS) on firms' market competitiveness has been a controversial issue with no consistent theoretical conclusions. The aim of this paper is to explore the impact of the carbon emission trading system on firms' markups using the latest robust staggered difference-in-difference estimation method. The results show that China's carbon emission trading system greatly contributes to the enhancement of firms' market power, as evidenced by a series of robustness tests. In addition, the analysis of the impact mechanism shows that the carbon emission trading system enhances the market power of firms through the low-carbon innovation effect and the market integration effect, while the impact of the environmental cost effect is not obvious. Moreover, the heterogeneity analysis shows that the impact of China's carbon trading system policy on firms' market power is more pronounced, especially for those firms that are actively involved in low-carbon transformation and upgrading, have a stronger cost-shifting capacity, and are more efficient in production. This study provides empirical evidence on how environmental regulations affect firms' market power and offers theoretical guidance for the construction of China's carbon market. [ABSTRACT FROM AUTHOR]

As the problems of "valuing compliance over trading" and quota over-allocation seriously affect the effectiveness of China's national carbon emission trading (CET) market, the quota auction mechanism will be introduced timely to solve these problems. Since implementing the quota auction means reduced free quotas, regulated enterprises are more motivated to pursue low-carbon technology innovation (L-CTI). On these grounds, by establishing a system dynamics model of the national CET market and designing seven scenarios for simulation analysis, this paper investigates the impact of quota auction and L-CTI on the emission reduction effectiveness and cost effectiveness of the national CET market. The results indicate that for the national CET market, introducing quota auction is conducive to decreasing the CET price and improving its liquidity and emission reduction effectiveness, which is one of the quota allocation mechanisms to improve the CET market effectiveness at present. However, the quota auction will increase the abatement cost and reduce the cost effectiveness. Therefore, to improve the institutional performance of China's CET system, it is necessary to conduct L-CTI to alleviate the increasing abatement cost caused by quota auction, and thus improve the emission reduction effectiveness and cost effectiveness of the national CET market. [ABSTRACT FROM AUTHOR]

Coordinated efforts to reduce haze and carbon emissions are important in promoting global climate governance and sustainable development. In this paper, based on prefecture-level data of China from 2005 to 2019, we investigate the impact of environmental regulatory intensity on the emissions of the concentration of PM2.5 and carbon dioxide (CO2). The research indicates that environmental regulation facilitates synergistic governance for PM2.5 reduction and carbon mitigation. Green technological advancement emerges as the primary mechanism through which environmental regulation achieves haze reduction and carbon mitigation. This conclusion remains robust after a series of robustness tests. Furthermore, the results from quantile regression reveal that the haze reduction and carbon mitigation effects of environmental regulation are subject to certain conditional dependencies. Environmental regulation exhibits a significant negative impact on carbon emissions across various quantile points. However, their influence on different quantile levels of PM2.5 concentration displays an asymmetric pattern. Finally, threshold regression findings suggest that there is no significant threshold effect of environmental regulation on CO2 emissions, but there are dual threshold effects on the PM2.5 concentration. Therefore, it is recommended that local governments judiciously implement environmental regulatory intensity, establish interregional policies for haze reduction and carbon mitigation, and fully harness the driving force of green technology to promote a comprehensive green transformation of economic and social development. [ABSTRACT FROM AUTHOR]

Solar vapor generation shows the great potential to produce clean water from salinity water. Efficient solar absorber plays a key role for high efficient solar vapor generator. Carbon materials have been utilized as solar absorber layer and show promising potentials. In this work, we prepared hierarchical porous carbon membranes (HPCM), comprising carbon nanofiber stringed porous carbon polyhedrons layer anchored on a carbonized filter paper (CFP), from a cellulose nanofiber (CNF) stringed metal organic framework (MOF) (HKUST-1) polyhedrons thin film grown on a filter paper by thermal carbonization. The resulted HPCM with hierarchical porous structures demonstrates different hydrophilicity between the carbon nanofiber stringed porous carbon polyhedrons top layer and bottom CFP layer, which not only ensures enough water supply to surface layer but also prevents excessive bulk water contacting with evaporating surface of higher temperature. When used as solar absorber for solar vapor generation, this HPCM exhibits an optimal water evaporation rate of 1.33 kg m−2 h−1 and solar vapor efficiency of 84.3%. This may provide a facile way to prepare high-performance, low-cost, light weight carbon membranes with flexible and reusability hierarchical porous structure for solar vapor generation. [ABSTRACT FROM AUTHOR]

Carbon emission trading has been actively applied in many countries, and its operational effect has received widespread attention. However, previous studies mostly focused on single environmental effect, and the investigation of the comprehensive environmental effect needs to be further supplemented. Based on this, this paper explores the comprehensive environmental effect of carbon emission trading with eco-efficiency as the starting point. First, this paper measures eco-efficiency using the super-efficient minimum distance to strong efficient frontier (MinDS) model with undesirable outputs. Second, this paper uses the propensity score matching difference in difference (PSM-DID) model to quantify the effect of carbon emission trading on eco-efficiency. Finally, this paper examines the mediating mechanism of the effect of carbon emission trading on eco-efficiency based on the mediating effect model. The results show that carbon emission trading can improve the level of urban eco-efficiency. Energy savings and increased efficiency effectively mediate the promoting effect of carbon emission trading on eco-efficiency. The mediating push effect of R&D innovation and industrial structure restructuring has not yet appeared. This paper can not only provide policy basis for the improvement of carbon emission trading market but also provide reference for the construction of carbon emission trading market in developing countries. [ABSTRACT FROM AUTHOR]

This paper conducts quasi-experiment design with Chinese listed companies microdata to investigate the effect and mechanism of corporate participation in carbon emission trading market on firm financial performance by using the staggered difference-in-differences method. We show that: a) corporate participation in carbon emission trading market can enhance firm financial performance; b) an increase in green innovation ability and a decrease in strategic choice variance both partially mediate the relationship between carbon emission trading and firm performance; c) executive background heterogeneity and external environmental uncertainty moderate the relationship between carbon emission trading and firm performance in different directions; d) our further study indicates that carbon emission trading pilot policy has a spatial spillover effect on firm financial performance in the neighboring provinces. Therefore, we recommend that the government and enterprises make an effort to further stimulate the vitality of corporate participation in carbon emission trading market. [ABSTRACT FROM AUTHOR]

Improving total factor carbon emission efficiency (TCE) is the key to achieving carbon emission reduction targets while ensuring economic growth. In this paper, the global Malmquist index based on the SBM model is used to measure TCE of 283 cities in China from 2011 to 2019. On this basis, this paper uses the spatial econometric model and intermediary effect model to empirically analyze the impact of industrial co-agglomeration on TCE and its transmission mechanism. Furthermore, considering the differences in geographical location and resource endowment among regions, this paper analyzes the heterogeneous effect of industrial collaboration agglomeration on TCE in different regions and cities. The results show that: (1) Industrial co-agglomeration can improve TCE, and its main transmission channel is technological innovation. (2) Industrial co-agglomeration has a positive spatial spillover effect. Industrial co-agglomeration in one region can improve the TCE in the surrounding regions. (3) Industrial co-agglomeration of cities with different geographic locations and resource endowments has a heterogeneous effect on TCE. Regarding geographical heterogeneity, the industrial co-agglomeration in the eastern region has the greatest promoting effect on TCE, followed by the central region. However, the impact of industrial co-agglomeration in the western region on TCE is not significant. Regarding resource endowment heterogeneity, the industrial co-agglomeration in non-resource-based cities has a greater promoting effect on TCE than that in resource-based cities. [ABSTRACT FROM AUTHOR]

This paper explores the spatial impact effects and spatio-temporal heterogeneity of the digital economy on urban carbon emissions (CO2). Specifically, firstly, the Digital Economy Index (DEI) system of 285 cities in China was constructed and the Global Principal Component Analysis (GPCA) was applied to evaluate the digital economy level of Chinese cities. Based on spatial correlation and spatial heterogeneity, the paper explores the global spatial impact and spatio-temporal heterogeneity of the impact of digital economy on CO2 using spatial Durbin model (SDM) and geographic time-weighted regression (GTWR), respectively. And the mechanism variables are used to further demonstrate the mechanism effect and nonlinear characteristics of the impact of digital economy on CO2. The findings indicate that (1) the advancement of the digital economy is beneficial for achieving carbon abatement goals, and the impact of the digital economy on CO2 mitigation remains stable across several robustness tests. (2) The spatial spillover effect of the digital economy on the impact of carbon reduction is not significant. And there is significant temporal and spatial heterogeneity in the impact of the digital economy on carbon emissions. (3) According to the mechanism analysis, the digital economy reduces carbon emissions by encouraging the development of green technologies and promoting the modernization of industrial structures. And there are non-linear characteristics of this effect. This study concludes that the digital economy can support China's goal of achieving "carbon peak and carbon neutrality." However, it is important to consider the differences in urban development over time and space. Leveraging the city's strengths to develop a digital economy in a unique way that will help achieve China's carbon reduction goals. [ABSTRACT FROM AUTHOR]

As the digital economy grows rapidly around the world, how would it impact carbon emissions? This paper discusses this issue from the perspective of heterogeneous innovation. Based on the panel data of 284 cities in China from 2011 to 2020, this paper empirically examines the impact of the digital economy on carbon emissions as well as the mediating and threshold effects of different innovation modes. The study finds that the digital economy can significantly reduce carbon emissions; this conclusion holds after a series of robustness tests. Independent innovation and imitative innovation are important channels through which the digital economy affects carbon emissions, but technological introduction is not an effective way. For regions with high levels of financial investment in science and innovative talents, the reduction in carbon emissions from the digital economy is more significant. Further research shows that the effect of the digital economy on carbon emissions has a threshold feature, with an inverted U-shaped relationship between the two, and that an increase in autonomous innovation and imitation innovation can enhance the digital economy's carbon reduction effect. Therefore, it is necessary to strengthen the capacity of independent innovation and imitation innovation to exploit the carbon-cutting effect of the digital economy. [ABSTRACT FROM AUTHOR]

This paper constructs a novel stress measurement system of carbon market from the perspective of trading, emission reduction, and external shocks and simulates the stress indices of national and pilot carbon markets of China with the methods of functional data analysis and criteria importance through intercriteria correlation. It concludes that the overall carbon market stress is in the shape of "W" and still at a high level, with frequent fluctuations and an upward trend. In addition, the stress of Hubei, Beijing, and Shanghai carbon market fluctuates and rises, while the stress of Guangdong carbon market decreases. Moreover, carbon market stress mainly comes from trading and emission reduction. Furthermore, stress fluctuation of Guangdong and Beijing carbon market is more prone to "big waves," indicating that the two markets are sensitive to big events. Finally, the pilot carbon markets are divided into stress-driven and stress-release market and the type of which keeps change in different period. [ABSTRACT FROM AUTHOR]

The serious consequences of climate warming have increasingly become a globe agenda in recent decades. China has been actively participating in various initiatives to address global climate change and has made commitments to reduce carbon emissions. Although the logistics industry is regarded as the "new driving force of national economic development", its carbon intensity is relatively high. Therefore, whether the logistics industry can develop in a green and low-carbon way is very crucial. This paper takes the green logistics efficiency of China's provincial logistics industry as the research object. The Super-SBM model is used to measure the China's green logistics efficiency, then the general dynamic characteristics is depicted by kernel density analysis. With the GML (Global Malmquist-Luenberger) index model, the reasons for the changes in green logistics efficiency are explained. Finally, Moran's I index is used to analyze the spatial correlation of green logistics efficiency in each province. The results show that the green logistics efficiency in China is at a low level, but with an upward trend. China's green logistics efficiency has a significant positive spatial correlation, showing a zonal pattern of high in the east and low in the west, and a polarization phenomenon. In addition, the bottleneck of the overall development of green logistics efficiency in China depends on the level of green technology. Furthermore, the results also imply that green technology advancement is an inherent key factor for green logistics efficiency to achieve growth. [ABSTRACT FROM AUTHOR]

The carbon emissions trading scheme (CETS) in China is an important market-based environmental policy mechanism for decreasing carbon emissions. This paper calculates the total factor carbon productivity (TFCP) based on data from 275 cities in China from 2007 to 2020 using the DEA method and investigates the impact of the CETS on regional TFCP using the differences-in-differences (DID) method, all against the backdrop of carbon peaking and carbon neutrality. The research findings reveal that CETS has consistently improved TFCP in pilot cities, and this conclusion has held up following a number of robustness tests. Temporal heterogeneity experiments demonstrate that as implementation time increases, the enhancing effect takes on an inverted "U-shaped" structure with a 7-year effective lifetime. Spatial heterogeneity studies reveal that as one moves away from the pilot cities, the policy effect on surrounding cities' TFCP is inhibited, followed by facilitation. CETS policies can influence regional TFCP through the effects of green innovation and industry upgrading, according to mediation mechanism testing. We present policy recommendations based on the research findings for meeting the "dual" carbon goals and strengthening the carbon trading mechanism. [ABSTRACT FROM AUTHOR]

This paper investigates the relationship between digital finance and carbon emissions and explores the ecological effects of digital finance. Based on a panel data of 256 cities in China from 2011 to 2018, this paper investigates the impact of digital finance on carbon emissions and its intrinsic mechanisms. First, digital finance significantly suppresses the intensity of regional carbon emission, and the breadth of coverage, depth of use, and degree of digital support of digital finance together curb regional carbon emissions, with the strongest suppressive effect being the breadth of coverage. In addition, the regression results remain significant after a series of robustness tests. Second, it reveals the potential mechanism of digital finance to curb urban carbon emissions. These mechanisms include the three channels: promoting industrial advancement, green technology innovation, and optimizing labor resource allocation. Third, the heterogeneity test finds that the energy saving and emission reduction effects of digital finance are significantly stronger in non-low-carbon pilot cities with low urbanization rates, confirming the emission reduction utility of digital finance development. Therefore, we should take advantage of digital finance to improve the green development of financial services and adopt diverse policy measures according to local conditions to maximize the ecological effects of digital finance on energy saving and emission reduction. In the context of the development strategy of "carbon peaking and carbon neutral," this study has some implications for management in developing a regional green development system supported by digital finance. [ABSTRACT FROM AUTHOR]

The intelligent city pilot policy is a major measure in China to promote urban development from factor driven and investment driven to innovation driven. Intelligent city construction can effectively coordinate specialized production factors and information sharing mechanism, promote digital information technology innovation, promote smart industry cluster, and expand ecological scenarios of clean industry application, so as to reduce carbon emissions. This paper reveals the internal mechanism of intelligent city construction to promote carbon emission reduction. Based on the quasi-natural experiments carried out in three batches of pilot construction of intelligent cities since 2012, the difference-in-difference model (DID) is used to identify its impact on urban carbon emissions. The research results show that the pilot construction of intelligent cities is conducive to reducing carbon emissions, which is still robust under multiple scenarios such as placebo test and endogenous test. Heterogeneity analysis shows that the pilot policies have a more significant carbon emission reduction effect on the Beijing-Tianjin-Hebei urban agglomeration, non-resource-based cities, and non-old industrial bases. After further quantitative analysis of 917 pilot policy texts based on Simhash algorithm, Jieba word segmentation, and word frequency statistics, it is found that intelligent industry policies reduce carbon emissions by driving data elements agglomeration and optimizing industrial structure, while intelligent government and intelligent people's livelihood policies improve energy efficiency and reduce carbon emissions through green technological innovation. Counterfactual tests using machine learning algorithms show that the later the pilot batch, the better the sustainable carbon emission reduction effect of intelligent city pilot policies. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to quantify the level of new-type urbanization and unravel the spatial and nonlinear effects of new-type urbanization and technological innovation on industrial carbon emissions. Although the impact of traditional urbanization levels on carbon emissions has been widely studied, there is still a huge room for optimization, and the impact of new-type urbanization on carbon emissions has not yet been clarified. Selecting 37 cities in the Yangtze River Delta as a research sample, this paper measures the new-type urbanization based on an evaluation system we build. Consequently, we assess the spatial and nonlinear effects of new-type urbanization and technological innovation on carbon emissions by the spatial Durbin model and non-parameter addictive model, respectively. The results indicate that the new-type urbanization and low-carbon city pilot policy have significant spatial spillover effects on reducing carbon dioxide emissions, while the economic growth plays a positive role in increasing carbon emission. As for nonlinear effects, there is a significant inverted "N"-shaped relationship between the level of new-type urbanization and carbon dioxide emissions, while the nexus between technological innovation and carbon emissions is an inverted "U"-shaped relationship. This paper provides a new perspective for confirming the mechanism of the new-type urbanization on carbon emissions. Meanwhile, these findings are of significance for the relevant authorities in China to develop appropriate policy in carbon dioxide emission reduction. [ABSTRACT FROM AUTHOR]

These authors contributed equally: Alexandre Poulin and Xavier Aeby. Correction to: I Scientific Reports i https://doi.org/10.1038/s41598-021-03075-4, published online 10 December 2021 The Acknowledgments section in the original version of this Article was omitted. [Extracted from the article]

From the perspective of configuration, this paper takes the region of manufacturing efficiency as the explanatory variable, selects eight antecedent conditions, and applies fuzzy set qualitative comparative analysis (fsQCA) to study the paths and methods of improving manufacturing emission efficiency. The results of the study show that there are two configuration paths of carbon emission efficiency in manufacturing industry, namely, research frontier and technological innovation level and labour force structure, R&D investment, science and technology innovation level, manufacturing output value, and environmental regulation synergistic path. [ABSTRACT FROM AUTHOR]

The interactive behaviors, such as competition and learning between local and neighboring cities, can lead to spatial spillover effects in policy implementation. Estimating the direct, indirect, and total effects of the carbon emission trading scheme (CETS) on green innovation is crucial to clarify its role and mechanisms. This paper applies the spatial difference-in-differences model to estimate these effects using data from 278 cities in China from 2009 to 2019. The results demonstrate that the CETS implementation catalyzes green innovation in pilot cities, which supports the Porter hypothesis. However, it has a negative impact on green innovation in neighboring cities of pilot cities, with this negative impact diminishing as distance increases. Notably, the total effect of the CETS is significantly negative, indicating that the CETS's average impact on green innovation in all cities is negative. Mechanism analysis reveals that the direct and indirect effects of the CETS on green innovation are strengthened in cities with higher levels of financial development, lower financial pressure, and easier economic growth targets. Notably, in cities with high-level industrial structures, the CETS not only enhances its contribution to green innovation but also mitigates its negative impact on neighboring cities. Furthermore, this paper explores the heterogeneous effects of the CETS from the perspective of its implementation measures. [ABSTRACT FROM AUTHOR]

Chemical molecular structures are a direct and convenient means of expressing chemical knowledge, playing a vital role in academic communication. In chemistry, hand drawing is a common task for students and researchers. If we can convert hand-drawn chemical molecular structures into machine-readable formats, like SMILES encoding, computers can efficiently process and analyze these structures, significantly enhancing the efficiency of chemical research. Furthermore, with the progress of educational technology, automated grading is gaining popularity. When machines automatically recognize chemical molecular structures and assess the correctness of the drawings, it offers great convenience to teachers. We created ChemReco, a tool designed to identify chemical molecular structures involving three atoms: C, H, and O, providing convenience for chemical researchers. Currently, there are limited studies on hand-drawn chemical molecular structures. Therefore, the primary focus of this paper is constructing datasets. We propose a synthetic image method to rapidly generate images resembling hand-drawn chemical molecular structures, enhancing dataset acquisition efficiency. Regarding model selection, the hand-drawn chemical molecule structural recognition model developed in this article achieves a final recognition accuracy of 96.90%. This model employs the encoder-decoder architecture of EfficientNet + Transformer, demonstrating superior performance compared to other encoder-decoder combinations. [ABSTRACT FROM AUTHOR]

In order to deal with severe problems such as environmental pollution and climate change, the Chinese government has proposed the goal of carbon neutrality in 2030 and carbon peak in 2060. Strategic emerging industries have become key areas of high-quality growth of green economy. In order to solve the practical problems of insufficient funds and financing constraints, this paper empirically measures the financing efficiency of strategic emerging industries. Based on the Super Slack-Based Measure model, this paper selects the data analysis of listed companies in Beijing, Tianjin and Hebei from 2011 to 2020. At the same time, this paper systematically combs the index system that affects financing efficiency based on grounded theory. Based on the binary relation and structural level of adjacent matrix and reachable matrix, the explanatory analysis is carried out. On this basis, a systematic GMM model is established to explore the significance of different factors influencing financing efficiency. The research shows that the strategic emerging industry is still in the initial stage, the financing efficiency is not high and the financing output is insufficient. The factors affecting financing efficiency can be divided into 6 dimensions, 20 indicators in total and 5 multipole hierarchical levels. Credit financing, equity financing, financing constraints, technological innovation and government support are the important factors affecting financing efficiency. [ABSTRACT FROM AUTHOR]

China needs to achieve its carbon peaking target with minimal economic costs. This paper proposes a framework for achieving the carbon peaking target that emphasizes economic effects. Based on the prediction, the parametric directional distance function (DDF) is adopted to calculate the total factor carbon emission efficiency and marginal carbon abatement cost in each region of China before 2030, and the allocation scheme of the abatement tasks necessary for carbon peaking is optimized from the perspective of least cost. The empirical results show the following: (1) The predicted rapid growth of China's economy from 2020 to 2030 will lead to a rapid increase in marginal abatement costs, with the average marginal carbon abatement cost increasing from 8,833 yuan/ton to 15,077 yuan/ton. The cost of carbon emission reduction in the future is very expensive. (2) The measured marginal abatement costs in China are positively correlated with carbon emission efficiency. In order to ensure economic development, developed regions should try to maintain the development trend, while the central and western regions take on more emission reduction tasks. (3) The emission efficiency is improved by optimizing the allocation scheme of the abatement tasks required to reach the peak, and the scientific and orderly path to reach the peak of each province and the corresponding lowest economic cost are obtained. This paper are of great theoretical and practical significance for the initial quota allocation in carbon trading market and ensuring the achievement of carbon peaking target under economic effect. [ABSTRACT FROM AUTHOR]

It is essential to predict carbon prices precisely in order to reduce CO2 emissions and mitigate global warming. As a solution to the limitations of a single machine learning model that has insufficient forecasting capability in the carbon price prediction problem, a carbon price prediction model (GWO–XGBOOST–CEEMDAN) based on the combination of grey wolf optimizer (GWO), extreme gradient boosting (XGBOOST), and complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) is put forward in this paper. First, a random forest (RF) method is employed to screen the primary carbon price indicators and determine the main influencing factors. Second, the GWO–XGBOOST model is established, and the GWO algorithm is utilized to optimize the XGBOOST model parameters. Finally, the residual series of the GWO–XGBOOST model are decomposed and corrected using the CEEMDAN method to produce the GWO–XGBOOST–CEEMDAN model. Three carbon emission trading markets, Guangdong, Hubei, and Fujian, were experimentally predicted to verify the model's validity. Based on the experimental results, it has been demonstrated that the proposed hybrid model has enhanced prediction precision compared to the comparison model, providing an effective experimental method for the prediction of future carbon prices. [ABSTRACT FROM AUTHOR]

One essential component that reflects the development of society and the economy of most countries is life expectancy (LEXP). Nevertheless, LEXP can be influenced by varying factors, including socioeconomic and medical factors. Therefore, this analysis's focal point and motivation is to explore how socioeconomic factors such as economic growth, technological innovation, carbon emission, human capital, and renewable energy affect LEXP. The study utilized panel data from 1990 to 2020 from the North American Free Trade Agreement (NAFTA), which consists of the USA, Mexico, and Canada. The initial test confirmed that the research series were stationary and cointegrated. Therefore, the research applied the cross-sectional autoregressive distributed lag (CS-ARDL) model to predict the paper's short- and long-term estimates. The empirical estimated model concluded that human capital, renewable energy, technological innovation, and economic growth boost life expectancy. Contrarily, the outcome espoused that carbon emission has an inverse association with LEXP. The causality test confirmed a unidirectional interaction between human capital, economic growth, technological innovation, and life expectancy. On the other hand, there is a bidirectional connection between carbon emission, renewable energy, and life expectancy. The research suggests that stakeholders and policy-makers strengthen and enforce air quality standards to reduce pollution from industrial emissions and vehicle exhaust and encourage using cleaner technologies to promote LEXP. The research outcome is empirically and theoretically consistent, providing an essential breakthrough for environment-health-energy and economic development policies. [ABSTRACT FROM AUTHOR]

Against the backdrop of low-carbon development, it is imperative to cultivate a modernized industrial system and new development model. Industrial collaborative agglomeration (ICA) between manufacturing and producer services may offer an opportunity to aid carbon reduction in this scenario. Using balanced panel data of China's 30 provinces and municipalities from 2008 to 2019, this paper attempts to investigate the influences of ICA on carbon emission efficiency (CEE), its heterogeneous effects, impact mechanisms, and spillover effects. Our main findings can be concluded as follows: (1) There is a U-shaped relationship between ICA and CEE; namely, ICA will inhibit first and then promote CEE. (2) The heterogeneity results further indicate that this U-shaped relationship is significant in the eastern area while there exists an inverted U-shaped relationship between ICA and CEE in the western area; however, the influence of ICA on CEE is not significant in the central area. (3) More deeply, the mechanism identification uncovers that industrial structure upgrading and green technological innovation are important channels through which ICA affects CEE. (4) Importantly, we unfold that ICA in the local area has spatial spillover effects; namely, it will influence CEE in neighboring areas, which also presents a U-shaped relationship. These findings provide not only new insights into understanding the environmental effects of ICA but also helpful inspiration for regional policymakers to scientifically formulate industrial development policies and effectively implement carbon emission control actions. [ABSTRACT FROM AUTHOR]

Agricultural carbon emission reduction is an important issue in environmental protection and development in China and the world. The farmland spatial transition is an important path for agricultural modernization in developing countries such as China. How can farmland spatial transition promote agricultural carbon emission reduction? This paper aims to explore the mechanisms and spatial-temporal effects of farmland spatial transition on agricultural carbon emission density. To study the mechanisms and effects, we establish the random effect model, the threshold model, and the GTWR model with 2018 counties in China from 2000 to 2020. The research shows the farmland spatial transition mainly promotes agricultural carbon emission reduction through the interaction mechanism of large-scale production and specialized production, intermediary, and threshold mechanisms of agricultural technology. The result also shows that specialized farmland management is the main driving force of agricultural carbon emission reduction for farmland spatial transition. Moreover, the impact of farmland spatial transition on agricultural carbon emission reduction has significant spatial and temporal differences. The most significant regions are located in the middle and lower reaches of the Yangtze River plain, while the least are the north and southwest. Besides, the impact of the farmland spatial transition on agricultural carbon emissions reduction has a "V" shape over time, indicating China's agricultural carbon emission reduction is facing enormous economic and social development challenges. Our research reveals the various mechanisms and spatial-temporal effects of the transition of farmland spatial morphology on agricultural carbon emission with an evaluation framework, which is crucial to low-carbon agriculture with proper farmland use. [ABSTRACT FROM AUTHOR]