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The control of carbon emissions from agriculture is imperative in addressing the challenges posed by the greenhouse effect. China must develop a specific pathway for reducing its agricultural carbon emissions, accounting for its unique circumstances and considering the impacts of trade liberalization. (1) The study revealing that agricultural trade liberalization (ATL) has a marked effect on lowering China's agricultural carbon emission intensity (ACEI), with robustness and endogeneity tests supporting these findings. (2) In the pursuit of emissions reduction, the crucial role of technology spillovers (TS) and the optimization of industrial structure (OIS) are essential. (3) The reduction in ACEI is particularly notable in coastal regions, areas with low environmental regulations and during periods characterized by more stable agricultural tariffs. This study shows a synergistic association between ATL and ACEI, indicates the potential for a mutually beneficial situation with advantages in both economic and environmental aspects. • Agricultural product trade helps to expand agricultural carbon emission reduction. • The paths of agricultural carbon emission effects in different characteristic contexts are explained. • The carbon emission reduction effect of agricultural trade is stronger in coastal areas. • The results of this study have significant implications for sustainable development. [ABSTRACT FROM AUTHOR]

The development of digital finance provides new opportunities for improving energy efficiency and promoting green development. This paper calculates green total factor energy efficiency (GTFEE) using the super-efficiency SBM model and examines the impact of digital finance on GTFEE. Digital finance has a significant positive impact on GTFEE. Under a bank-dominated financial structure, the positive impact of digital finance on GTFEE is quite significant. In regions with intense banking competition, a large amount of green credit, and lower resource dependence, digital finance is conducive to enhancing GTFEE. Optimizing the allocation efficiency of production factors is an essential mechanism for digital finance to encourage improvements in GTFEE. Digital finance alleviates distortions in factor markets and enhances the matching of the marginal output and the price of capital, labor, and energy factors, thereby facilitating improvements in GTFEE. Further analysis indicates that digital finance has a significant, positive spatial spillover effect on GTFEE, enhancing GTFEE levels in both local and neighboring regions. This study enriches the research on the relationship between digital finance and energy efficiency and provides theoretical foundations and policy references for how digital finance can better serve the green transition of the economy. • This paper analyzes the impact of digital finance on green total factor energy efficiency (GTFEE). • Digital finance alleviates distortions in factor markets, thereby promoting GTFEE. • Digital finance's impact on GTFEE depends on financial structure, banking competition, green credit and resource dependence. • Digital finance has a significant positive spatial spillover effect on GTFEE. [ABSTRACT FROM AUTHOR]

This study conducts conventional and advanced exergy, exergo-economic, and exergo-environmental analyses and comparisons of two tri-generation systems driven by solid oxide fuel cells (SOFCs) and gas turbines (GTs). The proposed systems mainly consist of SOFC, GT, heat recovery steam generator (HRSG), (organic) Rankine cycle, and heat exchanger. The analysis results indicate that the biggest cost rates of exergy destruction and component in both systems appear in SOFCs being 4.4333 $/h and 4.2760 $/h, while the highest environmental impact rates combined with exergy destruction and component in systems 1 and 2 are found in afterburner and HRSG, which are 645.9569 mPts/h and 849.2659 mPts/h. Compared to the conventional analyses, the advanced analyses demonstrate that air compressors own the largest avoidable-endogenous parts of cost rates, while HRSG of system 1 and steam turbine (ST) of system 2 own the highest avoidable-endogenous parts of environmental impact rates being 165.8482 mPts/h and 115.2299 mPts/h. • Two novel tri-generation systems driven by solid oxide fuel cells are proposed. • Conventional and advanced exergy-based analyses are performed and compared. • The biggest cost rates of exergy destruction and component appear in SOFCs. • The advanced exergo-economic and exergo-environmental factors are improved. [ABSTRACT FROM AUTHOR]

The Qinghai-Tibetan Plateau and its surrounding areas have a long and complex tectonic evolutionary history. Cratons and blocks, such as northern India, Lhasa, Qiangtang, Qaidam and Central Qilian, and their in-between orogenic belts constitute the main part of the Qinghai-Tibetan Plateau. During the Cambrian Period, most of these cratons and blocks were on the northwestern periphery of Gondwana, and were associated with the surrounding blocks, e.g. Arabian, Central Iran, Afghanistan, Tarim, Alxa, North China, South China and Sibumasu through the Proto-Tethys Ocean. The Cambrian stratigraphic sequences on these stable blocks are composed of mixed siliciclastic and carbonate rocks deposited in the shallow-water marine environments, and contain the trilobite assemblages of shelf facies. The Cambrian stratigraphic sequences in the Qilian tectonic belts, however, are characterized by the intermediate-basic igneous rocks and silicates formed in the Proto-Tethys Ocean, and contain the trilobite assemblages of deep-water slope facies. Combining with previous data, field observations and newly discovered fossils through funding by the Second Tibetan Plateau Scientific Expedition and Research, the general characteristics of the Cambrian strata in different tectonic units of the Qinghai-Tibetan Plateau and its surrounding areas have been summarized in this paper. Furthermore, efforts have been made to subdivide and correlate the Cambrian strata across these areas by utilizing available biostratigraphic and geochronological data. As a result, a comprehensive litho- and biostratigraphy chart has been compiled. Finally, from the biogeographic perspective, this paper also provides a brief overview of the Cambrian paleogeographical reconstruction of the major tectonic blocks, and discusses the problems associated with the evolution of the Proto-Tethys tectonic belt. [ABSTRACT FROM AUTHOR]

The complex evolutionary history of the Qinghai-Tibetan Plateau and its surrounding areas, including the continental blocks (Indian, Lhasa, South Qiangtang, Tarim, Olongbuluk, Central Qilian, Alxa, North China, Yangtze, Central Iran and Oman) and the orogenic belts between them, has long been the frontier in Earth science research. The Cryogenian and Ediacaran strata are extensively distributed in these blocks. Specifically, relatively complete Cryogenian and Ediacaran successions have been discovered in Oman, Indian, Yangtze, and Tarim blocks, while only the Ediacaran successions have been reported in Iran, the South Qiangtang, Central Qilian, Alxa, and North China blocks. Based on previous studies together with the integration of new materials and advancement obtained through the Second Tibetan Plateau Scientific Expedition and Research, this review aims to synthesize a correlative stratigraphic framework of the representative Cryogenian and Ediacaran sequences from the Qinghai-Tibetan Plateau and its surrounding areas. Furthermore, the Cryogenian and Ediacaran biotas and major geological events in these areas are comprehensively discussed in aspects of current research status. The results indicate that, in general, Ediacaran fossils of each area exhibit distinct features in preservation and assemblage composition, but the typical late Ediacaran fossils Cloudina and Shaanxilithes have been reported from most of these areas. In addition to the two global Cryogenian glaciations, late Ediacaran glaciogenic deposits are extensively recorded in the areas within and around the northern Qinghai-Tibetan Plateau (including the North China, Alxa, Central Qilian, Olongbuluk, and Tarim blocks, and the North Qilian Accretionary Belt), as well as central and southern Iran. However, further research is required to determine the age, distribution, and origin of these late Ediacaran glaciogenic deposits. Meanwhile, the middle Ediacaran DOUNCE/Shuram Excursion is widely documented in the Qinghai-Tibetan Plateau and its surrounding areas. The available data show that, after the break-up of the Rodinia supercontinent, most of the continental blocks in the areas were located along the northern margin of East Gondwana and a few (such as North China) were located between the Gondwana and Laurentia. In general, the paleogeographic evolution of most of these blocks during the Cryogenian and Ediacaran remains disputatious, necessitating further research to resolve the controversies surrounding their paleogeographic reconstruction models during this critical time interval. [ABSTRACT FROM AUTHOR]

The reactivity-controlled compression ignition (RCCI) engines fueled with polyoxymethylene dimethyl ethers (PODE n) and hydrogen (H 2) demonstrate great potential in enhancing engine performance because of the beneficial fuel properties of PODE n. This study comprehensively investigates the performance of H 2 /PODE n RCCI at medium load with the gross indicated mean effective pressure of roughly 6 bar in a single-cylinder light-duty compression-ignition engine. The results showed that H 2 /PODE n RCCI has a more retarded ignition timing than that of H 2 /diesel RCCI under the same premixed energy ratio because the higher heat of absorption of PODE n reduces the bulk-gas temperature during the evaporation process owing to its higher latent heat of vaporization and lower heating value. Moreover, the combustion of H 2 shifts from flame propagation in H 2 /diesel RCCI to spontaneous auto-ignition dominated by the reactivity stratification in H 2 /PODE n RCCI, because the higher fuel reactivity and greater volatility of PODE n enhance the mixing of direct-injection PODE n and premixed H 2 , and promote the auto-ignition reactivity of the H 2 /air mixture. Overall, H 2 /PODE n RCCI exhibits a greater advantage in the ignition control than H 2 /diesel RCCI to achieve successive ignition and reduce heat release rate due to its higher sensitivity of combustion to fuel reactivity gradient. Based on this benefit, H 2 /PODE n RCCI considerably improves engine thermal efficiency and simultaneously reduces peak pressure rise rate and soot emissions, in particular realizing an order of magnitude decrease in nitrogen oxides emissions compared to H 2 /diesel RCCI. [Display omitted] • The combustion characteristics of H 2 /PODE n RCCI were extensively investigated. • The auto-ignition/flame propagation mechanism for H 2 combustion was identified. • The H 2 combustion in H 2 /PODE n RCCI is governed by multi-point auto-ignition. • H 2 /PODE n RCCI is able to significantly enhance thermal efficiency. • H 2 /PODE n RCCI can substantially reduce NO x emissions. [ABSTRACT FROM AUTHOR]

Among many technical routes in solving the SCR (Selective Catalyst Reduction) deposition problem, a good mixer design can greatly improve the NO x conversion efficiency of the exhaust after-treatment system while avoiding urea deposition failures. This paper presents an anti-deposition mixer with novel conception which was optimized through CFD method, the more layers of wire mesh plates, the lower the evaporation efficiency is affected by the increase in injection volume. The new mixer with three layers of wire mesh plate shows better deposition resistance performance below 250℃through urea deposits boundary experiment, and it reduces the NO x emission value by 9.5% than conventional scheme under WHTC (Word Harmonized Transient Cycle) and WHSC (Word Harmonized Steady-state Cycle) test. By using the new mixer scheme in the after-treatment system, the problem of deposition under a variety of low emission temperature can be solved. • A new conception mixer make SCR system avoiding from urea deposition. • The new mixer scheme improve the engine emission limit of NO x by 9.5%. • The new mixer has excellent urea deposition resistance performance below 250 ℃. [ABSTRACT FROM AUTHOR]

• Palynological investigation of late Paleoproterozoic Chuanlinggou Formation from North China is performed. • The iconic spinose eukaryote Tappania plana is first reported here in Yanliao Basin. • Diverse prokaryotic filaments dominated the Tappania -containing microfossil assemblage. The first radiation of eukaryotic life in Earth history began at least by the late Paleoproterozoic as evidenced by complex organic-walled microfossils from North China, India and Australia. However, among these oldest eukaryotic fossils, the spinose Tappania plana Yin, 1997 , which has been reported from the late Paleoproterozoic to early Mesoproterozoic sediments worldwide, is strangely absent in the well-known microfossil assemblages from the coeval strata in the Yanliao Basin, North China. Here we report the new finding of T. plana and associated microfossils from ∼ 1.64 Ga Chuanlinggou Formation in the eastern Yanliao Basin. T. plana occurs in the assemblage from the upper Chuanlinggou Formation and exhibits typical irregularly distributed tubular processes and neck-like extensions. The assemblage is dominated by a wide variety of filamentous microfossils likely representing cyanobacterial or other bacterial sheaths and trichomes, and includes 21 species (belonging to 10 genera) and 3 unnamed forms. In contrast, the assemblage from the lower Chuanlinggou Formation is composed of only simple spheroidal (Leiosphaeridia) and fusiform (Schizofusa) morphotypes, distinct from those of the upper assemblage. This taxonomic discrepancy likely resulted from different paleoenvironments. Overall, the occurrence of T. plana in the Yanliao Basin expands its paleographic distribution and further reinforces its stratigraphic potential as an index fossil for the late Paleoproterozoic and early Mesoproterozoic strata. Furthermore, the microfossil assemblages reported here document a microbiota overwhelmingly dominated by prokaryotic organisms, which is consistent with the hypothesis that eukaryotes likely constituted as marginal groups in ancient ecosystems during mid-Proterozoic. [ABSTRACT FROM AUTHOR]