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Objective Study of the Quaternary stratigraphical characteristics of the eastern Songnen Plain is of particular importance for gaining an understanding of regional climate change and the evolution of sedimentary environments. To data, however, there has been comparatively little research focusing on the Quaternary strata in this area, which has accordingly limited our comprehension of the mechanisms underlying changes in the regional climate and environment. Methods In this study we focused on the borehole WKZK01 in the eastern Songnen Plain. On the basis of lithological characteristic analysis, we obtained dating, sedimentary environment evolution, and climatic evolution information using optically stimulated luminescence, palynology, and laser grain size analytical methods, and based on comparisons with the results obtained from a typical Huangshan section, Harbin, we discuss the Quaternary stratigraphy of the borehole and the sedimentary environments it reflects. Results The Quaternary strata in Wangkui county are divided from old to new as follows: the middle Pleistocene Huangshan Formation, the middle Pleistocene Harbin Formation, and the upper Pleistocene Guxiangtun Formation, with an absence of a Holocene Tantu Formation. The Huangshan Formation is 13.05 m thick, with a median grain size (Md) ranging from 7.77 μm to 11.84 μm, and an average value of 9.62 μm. Pollen zone I-1 is dominated by xerophytic herbaceous pollen, with small amounts of mixed coniferous and broadleaf woody plant pollen, although lacks pollen derived from hydrophilic herbaceous plant. The Harbin Formation is 24.05 m thick, with a median grain size (Md) ranging from 9.67 μm to 14.98 μm, and an average value of 11.74 μm. Pollen zone I-2 is still dominated by xerophytic herbaceous pollen, with that derived from mixed coniferous and broadleaf woody plants as the secondary component, and the appearance of hydrophilic herbaceous plant pollen. The Guxiangtun Formation is 15.6 m thick, with a median grain size (Md) ranging from 11.61 μm to 19.91 μm, and an average value of 14.12 μm. Compared with the earlier stages, pollen zone II has a less abundant pollen content, although is characterized by an increase in hydrophilic herbaceous pollen, and a marked decline in the content of pollen derived from xerophytic woody and herbaceous plants. Conclusion The Huangshan Formation represents lacustrine deposits, with pollen zone I-1 providing evidence of a cool and dry climate during the early Middle Pleistocene. The Harbin Formation also comprises lacustrine deposits, with the pollen record in zone I-2 indicating a cool and humid climate during the late Middle Pleistocene. The Guxiangtun Formation comprises fluvial deposits, with pollen zone II recording a cold and wet climate during the Late Pleistocene. Significance The borehole WKZK01 provides a record of the environmental evolution of a small lake adjacent to the large Songnen paleolake, revealing a transition from the lake center to the margin and eventually disappearing with the formation of rivers.

Based on the physical parameters of the rocks (ores) and the genetic types of ore deposits, the geophysical exploration models have met issues of multiple solutions for deep prospecting prediction. It is necessary to find recognizable geological targets with high precision by geophysical methods. The ore prospecting practice over past years has demonstrated that the ore field tectonic deformation lithofacies belt is an outstanding target and significant prospecting results have been achieved. At present, the geophysical exploration work of large-scale mining area is heavy, while that of medium-scale ore field is limited, and both of them lack the strategic guidance at different levels. In order to establish the geophysical identification mark of the tectonic deformation lithofacies belt in ore field, it is necessary to clarify the complex time-space relationship between geology and geophysics, and strengthen the connection between geomechanics and geophysical exploration methods. In this paper, a method of processing and interpreting geophysical information at different levels is proposed. According to the "✳-shaped" structural features of the tectonic traces in the study area and the characteristics of the periodic development of the tectonic system, the geophysical exploration data of different scales and dimensions are analyzed from the two levels of ore field and deposit, and the information of tectonic deformation lithofacies belts is extracted. The specific operation procedures are as follows: (1) Making an area geophysical exploration within the scope of the ore field, interpreting the "✳-shaped" fault structure system, and then selecting the tensional and tension-torsional ore-bearing fault structures and predicting the prospecting direction; (2) Laying out large-deep geophysical profiles in the ore-bearing fault zone, analyzing the denudation degree and burial depth, and delineating the location of prospecting targets based on the geochemical exploration information. The application results of this method in the Chaihulanzi gold field in Chifeng, Inner Mongolia is introduced. The "✳-shaped" distribution of structural traces of the Neocathaysian tectonic system are interpreted from the geophysical data of the ore field, and then it is confirmed that the NNW and NWW trending tectonic deformation lithofacies belts are the main ore-bearing structural belts and there is a spatio-temporal sequential relationship between them in the two mining areas. These findings, provides a basis for deep ore prospecting and prediction.

Aiming at the shear failure of drilling casing, based on the movement law of overlying strata in coal seam mining, the finite element model of shear deformation of drilling casing is established by ANSYS numerical simulation software, and the effect of different strata dip angles on the stress distribution in the shear deformation area of drilling casing is simulated and analyzed. The results show that after shear deformation of casing, the shear plane changes from original circular to elliptical, and the end point of elliptical long axis is the stress concentration area of shear stress. Increasing the dip angle of strata will result in the increase of the stress concentration area of casing shear stress, and the maximum shear stress in the stress concentration area also gradually increases.

Cost-effective strategies for enhancing performance of lithium metal batteries (LMB) are in high demand. Herein, we propose and demonstrate that applying an external acoustic field can significantly enhance LMB performance, offering a novel approach to advancing battery technology. Long-term electrochemical stability tests, along with SEM and XPS characterization, reveal that this enhancement may result from the increased lithium-ion diffusion at slip lines and kinks, which can enable a more uniform solid electrolyte interphase (SEI) layer. Without the acoustic field, lithium ions exhibit slower conduction through thicker SEI regions, influenced by slip lines and kinks. In contrast, the application of an acoustic field facilitates more uniform ion diffusion, thereby enhancing overall performance. This approach provides a valuable pathway for advancing battery technology beyond the traditional focus on material innovation. [ABSTRACT FROM AUTHOR]

Sodium metal batteries (SMBs) are cost-effective and environmentally sustainable alternative to lithium batteries. However, at present, limitations such as poor compatibility, low coulombic efficiency (CE), and high electrolyte cost hinder their widespread application. Herein, we propose a non-flammable, low-concentration electrolyte composed of 0.3 M NaPF6 in propylene carbonate (PC), fluoroethylene carbonate (FEC), and 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether (TTE). This low-concentration electrolyte not only reduces cost but also delivers rapid ion diffusion and superior wetting properties. While the Na||FePO4 system with this electrolyte demonstrates slightly reduced performance at room temperature compared to standard-concentration formulations (S-PFT), it excels at both high (55 °C) and low (−20 °C) temperatures, showcasing its balanced performance. At 0.5 C (charge)/1 C (discharge), capacity retention reaches 92.8% at room temperature and 98.5% at elevated temperature, with CE values surpassing 99% and 99.63%, respectively, and significant performance sustained at −20 °C at 0.2 C. This electrolyte development thus offers a well-rounded, economically viable path to high-performance SMBs for diverse environmental applications. [ABSTRACT FROM AUTHOR]

The severe service environment of steel bridges put forward strict requirements for the deck pavement, especially the flexibility of paving materials. In this study, a new super tough resin-based concrete (STRC) was introduced and a comparative study of STRC and epoxy asphalt concrete (EAC) performance was conducted. Specifically, the high-temperature stability, low- and intermediate-temperature flexibility, fracture resistance, and fatigue properties were characterised by the dynamic creep test, beam bending test, semi-circular bending test, and semi-circular fatigue test, respectively. According to the results, at 70°C, the cumulative strain after 10,000 cycles of loading is about 2700μϵ and 900μϵ for STRC and EAC, respectively. At −10°C, the maximum tensile strain of EAC is only 2419 μϵ, which is significantly lower than that of STRC (17000 μϵ). For the cracking resistance, STRC exhibits larger total fracture energy, pre-peak and post-peak fracture energies, which indicates the excellent cracking resistance of STRC. Furthermore, the fatigue life and accumulated dissipated energy of STRC are higher than that of EAC. Besides, the tensile strain growth rate of EAC is significantly greater than that of STRC, which implies a lower crack propagation rate and better fatigue resistance of STRC. [ABSTRACT FROM AUTHOR]

In the rapid development of urbanization, the sustained and healthy development of transportation infrastructure has become a widely discussed topic. The inspection and maintenance of asphalt pavements not only concern road safety and efficiency but also directly impact the rational allocation of resources and environmental sustainability. To address the challenges of modern transportation infrastructure management, this study innovatively proposes a hybrid learning model that integrates deep convolutional neural networks (DCNNs) and support vector machines (SVMs). Specifically, the model initially employs a ShuffleNet architecture to autonomously extract abstract features from various defect categories. Subsequently, the Maximum Relevance Minimum Redundancy (MRMR) method is utilized to select the top 25% of features with the highest relevance and minimal redundancy. After that, SVMs equipped with diverse kernel functions are deployed to perform training and prediction based on the selected features. The experimental results reveal that the model attains a high classification accuracy of 94.62% on a self-constructed asphalt pavement image dataset. This technology not only significantly improves the accuracy and efficiency of pavement inspection but also effectively reduces traffic congestion and incremental carbon emissions caused by pavement distress, thereby alleviating environmental burdens. It is of great significance for enhancing pavement maintenance efficiency, conserving resource consumption, mitigating environmental pollution, and promoting sustainable socio-economic development. [ABSTRACT FROM AUTHOR]

Electron donor–acceptor (D–A) molecules are emerging tools for designing sensitive luminogens, attracting significant research attention. However, due to poor quantum yields under certain conditions, current D–A fluorophores often suffer from fluorescence quenching in practical applications. Developing new D–A dyes and functional composites is crucial for expanding their applications. Here, a novel donor–acceptor type flavonoid dye molecule, namely “AFL”, exhibiting both polarity‐dependent fluorescence emission wavelength shift and viscosity‐dependent intensity change, for polarity measurement and temperature sensing is designed and synthesized. Because the intramolecular charge transfer (ICT) can be enhanced by a decrease of excited state energy caused in high‐polarity organic solvents, AFL undergoes fluorescence emission wavelength shift that shows fluorescence color response to solvents of different polarities and hence differentiates between them. Moreover, the actual temperature can be monitored by the as‐designed AFL@tetradecanoic acid (AFL@TA) sensor. By combining with TA, viscosity sensitively changes upon the temperature change of insoluble composites, thus realizing the fluorescence intensity response to temperature. Remarkable recyclable performance and satisfactory mechanical properties are integrated. This study provides a promising approach to developing a new D–A fluorescent probe and furnishes perspectives on the potential of such D–A type flavonoid material in stimuli‐responsive systems with a focus on visualization sensing technology. [ABSTRACT FROM AUTHOR]

Background: Dengue, a mosquito-borne viral disease, has occurred in many cities in China, and it tends to spread to higher latitudes (Huang et al., 2023). Xi'an, situated in central-west China, has witnessed an increase imported cases in the past few years, raising concerns of local dengue transmission. It is crucial to investigate the population density of Aedes albopictus and its insecticides resistance to enhance early warning of dengue fever. Methods: Eight sampling sites in eight counties (YT, BL, WY, CH, YL, LN, LT, ZZ) of Xi'an city were surveyed by larval dipping and human-baited double net trap biweekly from June 2021 to September 2022. The Breteau Index (BI, number of positive containers per 100 houses) and Container Index (CI, the percentage of containers containing larvae or pupae) were used to assess larval density, and the human-baited double net trap (HDN, the number of Ae. albopictus females collected per person per hour) to indicate human bating rate (HBR). Meanwhile, the association between the meteorological factors and mosquito density was analyzed. The Ae. albopictus adult insecticides resistance was evaluated by the World Health Organization (WHO) standard resistance bioassay. Adult females were exposed to insecticide-impregnated paper for 1 h, then transferred to the recovery tube, and mortality rate was calculated after 24 h. According to the Implementation Plan for National Vector Surveillance (2016), resistance status was classified into three levels based on mortality: <80% mortality as resistant, between 80% and 98% mortality as possibly resistant, and >98% mortality as sensitive. Results: From June 2021 to September 2022, a total of 1,065 houses were surveyed for water holding containers, and 99 of 430 water holding containers were checked to be positive for Ae. albopictus larvae and pupae. A total of 1,048 Ae. albopictus females were collected. The average BI, CI and HBR were 10.39, 21.41, and 11.20 female/man/hour in 2021 and 8.86, 20.86, and 11.63 f/m/h in 2022, respectively. The findings showed that the BI exceeded 5 in most months and reached above 20 in specific months. The CI varied in different months and monitoring sites, with the highest CI in August 2021 and July 2022. The discarded tires had the highest positivity rate, with up to 40.32% testing positive for Ae. albopictus larvae. The monthly average temperature showed a positive correlation with CI (r = 0.77), and the monthly BI was positively associated with CI (r = 0.93). The BI, CI, and HBR were significantly higher in the rainy season than other seasons. The bioassay results showed that the mortality rate of Ae. albopictus at the YT monitoring site was 76.92%, indicating resistance to deltamethrin. The mortality rate of Ae. Albopictus at BL, WY, CH, YL, LN, LT, and ZZ sampling sites were varying from 81.25%∼100%, suggesting possibly resistant or still sensitive to beta-cypermethrin, alpha-cypermethrin, malathion, chlorpyrifos, and propoxur. [ABSTRACT FROM AUTHOR]

Cyclotides are plant cyclic peptides with exceptional stability and diverse bioactivity, making them promising candidates for biomedical applications. Therefore, the study of cyclotides has attracted increasing attention in recent years. However, the existing cyclotide detection methods face limitations in sensitivity, accuracy, and reliability. To address these challenges, we developed an integrated strategy using a combination of strong cation exchange chromatography techniques for removing interfering small molecules, Orbitrap Exploris 480 mass spectrometry (OEMS); this is a detection and database searching-based method for cyclotide verification, which greatly improved the sensitivity, accuracy, and reliability of cyclotide identification. This strategy was subsequently employed for cyclotide mapping in Viola with a minute amount of starting tissue, resulting the identification of 65 known and 18 potentially novel cyclotides, which is the largest dataset of cyclotides for Viola philippica. This strategy provided valuable insights into the cyclotide diversity and distribution in V. philippica, with potential applications in drug discovery and other biomedical fields. [ABSTRACT FROM AUTHOR]