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China’s agricultural and rural greenhouse gas emissions account for about 15% of its total emissions. Studying how to reduce China’s agricultural carbon emissions (ACEs) is of great strategic significance. Based on the panel data of 31 provinces (cities) in China from 2007 to 2020, this paper empirically tests the impact of fiscal environmental protection expenditure (FEPE) on ACEs. The results reveal that: FEPE has significant negative impacts on ACEs; FEPE has a heterogeneous impact on ACEs in different regions, which shows that it has a significant impact on the eastern and central regions and provinces with relatively “high” carbon emissions, while it has no significant impact on the western regions and provinces with relatively “low” carbon emissions; Further the results of mechanism analysis show that the impact of FEPE on ACEs is mainly manifested in its inhibiting effect on agricultural diesel, fertilizer and film use of carbon emissions. In light of these findings, it is imperative for the government to ensure steady and substantial investments in environmental protection. Moreover, implementing region-specific measures is essential to effectively curbing ACEs. The findings of this study offer invaluable insights that can guide the formulation of policies aimed at effectively reducing ACEs.

The marine carbonate reef–shoal reservoirs in the gentle slope platform margin of the M block, eastern Sichuan Basin, were well developed during the Changxing Period in late Permian and represent a favorable carbonate reservoir play for petroleum exploration. The lack of effective research methods has hindered the analysis of their unique sedimentary characteristics and controlling factors. Based on cores, thin sections, well logs, testing analyses, and high-resolution 3D seismic data, this study analyzes the lithological associations, microfacies types, reservoir physical properties, and seismic reflection characteristics of reef–shoal reservoirs. On this basis, the reef–shoal sedimentary characteristics and controlling factors were analyzed. The main conclusions are as follows: (1) Two major categories and eight subcategories of petrography were identified in marine carbonate reef–shoals, and five microfacies were identified: reef base, reef core, reef flank, reef-top–shoal, and inter-reef sea. Among these, the reef-top–shoal constitutes the optimal reservoir, while the reef flank develops secondary reservoirs. (2) The reef–shoals exhibit an external mound or wedge-shaped reflection, with internally discontinuous or chaotic reflections. Discontinuous reflections are observed at the top, while onlap terminations are present on its flanks. (3) The vertical accretion of the marine reef–shoals is small, but the platform margin belt is wide in planar, multiple rows reef–shoal bodies are identified, reflecting their small scale, discrete planar distribution, rapid lateral migration, and diverse stacking patterns. (4) The regional gentle slope marine platform margin geological setting, tectonic paleogeomorphology, and high-frequency sea level fluctuation collectively control the sedimentary structure and the formation of high-quality reservoirs of the marine reef–shoal complex. This research provides guidance for petroleum exploration and favorable reservoir prediction in the marine carbonate reservoirs of the Sichuan Basin.

Improving energy utilization efficiency is an essential way to save energy and reduce emissions. This article collects data from 3,164 samples in China and uses the SBM-DEA method to calculate energy utilization efficiency. Then, we construct the DID model based on China’s New-Energy-Demonstration-City (NEDC) policy to test the impacts of local government intervention on energy utilization efficiency (EUE). The following conclusions can be drawn. Firstly, the NEDC policy can still significantly improve EUE. Secondly, heterogeneity analysis shows that the NEDC policy is beneficial for enhancing urban EUE, whether for traditional industrial bases or non-traditional industrial bases. The impact on non-traditional industrial bases is greater. The NEDC policy can significantly promote EUE in the eastern cities and high economic development areas. In contrast, its impact on EUE in the central and western cities or low economic development areas is insignificant. Finally, mechanism analysis shows that NEDC policy can promote energy utilization efficiency through industrial structure adjustment and green innovation.

The development pattern of the high-quality reservoir in the Changxing Formation in the Wolonghe-Yangduxi area of southeastern Sichuan is complex. To clarify its evolution, genetic mechanisms, and distribution patterns, this study integrates data from profiles, cores, thin sections, and well logs. It reveals the distribution mechanisms of the bio-reef and shoal reservoirs in the Changxing Formation and discusses the controlling effects of tectonic, sedimentary, and diagenetic processes on reservoir development. The results show the following: (1) The Changxing Formation mainly develops open platform facies, platform margin facies, and slope-basin facies, which can be further subdivided into subfacies of platforms, intra-platform depressions, intra-platform depressions marginal reefs, and intra-platform depressions marginal shoals. The intra-platform margin reefs and the reefs at the edge of the platforms are favorable microfacies for reservoir development. (2) The high-quality reservoirs of the Changxing Formation are dominated by medium-thick-layered biogenic reef limestone and bioclastic limestone, with secondary porosity as the main reservoir space. (3) Sedimentary conditions, sea level fluctuations, and diagenesis are crucial factors for reservoir development. Paleogeomorphological conditions provide the foundation for reservoir development, while sea level fluctuations control the internal structure of the reef–shoal and the cyclical variations in the reservoir.

In order to clarify the controlling effects of tectonic activity on hydrocarbon migration efficiency in the Permian–Triassic strata of the Luzhou area, Sichuan Basin, this study takes faults as the research objective. Using 3D seismic data, tectonic evolution records, and single-well test data, we systematically analyze the geometric characteristics, activity phases, classification by grade and type, and reservoir-controlling effects of faults. The results show that a total of 843 reverse faults have been identified in the study area. The major faults are distributed in a NE-SW trend, with eight planar combination styles developed, and the main cross-sectional styles are back-thrust and “Y”-shaped types. The faults experienced four phases of tectonic activity: Caledonian, Hercynian, Indosinian, and Yanshan–Himalayan. Among these, the Indosinian phase is the key formative phase, effectively connecting the source rocks and reservoirs. The faults are classified into three grades and four categories: source-connected faults, reservoir-modifying faults, damaging faults, and source-connected and damaging faults. Migration efficiency is jointly controlled by fault grade, activity phases, and the penetrated formations. Among them, third-order source-connected faults formed during the Indosinian phase exhibit the highest migration efficiency, while first-order damaging faults formed during the Yanshan phase tend to cause hydrocarbon dissipation. This study can provide a reference for hydrocarbon exploration and the prediction of favorable areas in the Luzhou area.

Quantum-state manipulation through coherent interaction with a radiation field is a fundamental process with broad implications in quantum optics and quantum information processing. However, current quantum control methods are limited by their operation at Rabi frequencies below the gigahertz range, which restricts their applicability to systems with long coherence times. To overcome this limitation, alternative approaches utilizing ultrafast driving lasers have garnered great interest. In this work, we demonstrate two-photon Rabi oscillations in the excited states of argon operating at terahertz frequencies driven by ultrafast laser pulses. Leveraging quantum-path interferometry, we are able to measure and manipulate both the amplitudes and phases of the transition dipoles by exploiting the intensity and polarization state of the driving laser. This precise control enables femtosecond population transfer and coherent accumulation of geometric phase. Our findings provide valuable insights into the all-optical manipulation of extreme-ultraviolet radiations and demonstrate the possibility of ultrafast quantum control through interferometric multiphoton transitions. Quantum control with coherent radiation fields typically operate at Rabi frequencies below the GHz, limiting the applicability of this scheme to systems with long coherence times. Via quantum path intereferometry, the authors overcome this limitation and control two-photon Rabi oscillations between excited states driven by femtosecond laser pulses.

The provenance of the Upper Carboniferous Benxi Formation in North China Craton (NCC) has been considered as the northern margin of the NCC, not the North Qinling Orogenic Belt. To understand the provenance and the tectonic-sedimentary evolution during the sedimentary period of the Benxi Formation, the zircon U–Pb geochronology analysis was conducted on eleven clastic sandstone samples. The south of the NCC received clastic sediments from the North Qinling Orogenic Belt. The orogenic movements around the NCC in the Late Carboniferous period had significant impacts on the changes in paleotopography. During the early sedimentary period of the Hutian member of the Benxi Formation, the north of the Qinling Orogenic Belt was rapidly uplifted, and paleotopography was south-uplifting and north-dipping; thus, the clastic source was the North Qinling Orogenic Belt. From the late sedimentary period of the Benxi Formation Hutian member to the sedimentary period of the Jinci member, paleotopography was reversed. The northern margin of the NCC quickly uplifted, and paleotopography was north-uplifting and south-dipping. Two distinct provenances were present in the sediments of the Benxi Formation. The sediments were supplied predominately by the provenance in the north.

We theoretically develop and experimentally demonstrate a holographic method for imaging cold atoms at the diffraction and photon shot noise limits. Aided by a double point source reference field, a simple iterative algorithm robustly removes the twin image of an 87Rb cold atom sample during the image reconstruction. Shot-noise limited phase shift and absorption images are consistently retrieved at various probe detunings, and during the laser cooling process. We consistently resolve less than 2 mrad phase shift ( attenuation) of the probe light, outperforming shot-noise limited phase-contrast (absorption) imaging by a factor of 4 or more if the same camera is used without pixel saturation. We discuss the possible extension of this work for precise phase imaging of dense atomic gases, and for off-resonant probing of multiple atoms in optical lattices.

In situ U-Pb dating of carbonates is very common in the fields of mining and petroleum geology. However, carbonate minerals generally have low U, high common Pb, multiple generations, and uneven elemental distribution, often resulting in relatively low dating precision. Hence, the success rate in U-Pb dating of carbonates by the traditional spot analysis method is generally low. This paper, through combining a mapping method for U-Pb dating with a proprietary visualization and analysis software, ChronoVA, conducted a comparison of the data obtained by both the spot analysis and the mapping method for 3 carbonate standards and 2 unknown natural geological samples. We successfully developed a U-Pb dating method for carbonate rocks via LA-SF-ICP-MS elemental mapping and discussed the advantages and limitations of this method. Results show that in comparison with the traditional spot analysis method, the mapping approach has the following advantages: (1) reducing the downhole fractionation effect; (2) simplifying the analytical processes; (3) the elemental imaging data can help to identify multi-generation and mineral inclusions, ensuring the obtained carbonate U-Pb age having an interpretable geological meaning; (4) a large amount of mapping data can significantly improve the accuracy of the dating results. Despite these advantages, in carbonate samples with extremely high common Pb content and high Pb/U ratio, it might be difficult to obtain reliable ages even via the mapping method. In addition, it was understood that the carbonate standard WC-1, which is the most commonly used at present, could be inhomogeneous, and on occasion does not satisfy the SK model in spot analysis.