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Abstract A large-scale, high-speed, long-runout landslide occurred in Xinmo Village, Maoxian, Sichuan Province, China, on June 24, 2017. It was characterized by fast sliding speed, rapid volume growth, and large impact area. The dynamic process of such landslides and the influence of erosion on the dynamic process are studied by field investigation, numerical inversion and simulation. The results showed that entrainment erosion was a major factor of landslide volumetric change and a salient feature of the landslide process. An exponential equation relating the erosion rate and the deposition volume was established. Moreover, the study found that a slight change of the erosion rate (1e-4) also had a significant impact on the lateral spreading, longitudinal runout, and vertical erosion. As the erosion rate increased, the lateral spreading, longitudinal runout, and vertical erosion of this type of landslide became more obvious. By using the coefficient of variation method, it was obtained that the erosion rate had a greater influence on the vertical erosion than on the lateral spreading and longitudinal runout. In the study of the velocity of the rock avalanche under different erosion conditions, it was found that the erosion amount and the landslide velocity were not strictly linearly related. This study has important significance for understanding the dynamic process and erosion effect of rock avalanche, and provides useful references and insights for future research in related fields.

The access methods for terminal communication on the distribution network side are diverse. However, due to the lack of complete interconnection among various communication methods, the reliability of communication is compromised. Therefore, it is of great significance to realize automatic switching of various communication access modes and multi-network integration of terminals to improve the reliability of distribution communication network. Based on the research on the wide application of mature technologies such as bidirectional forwarding detection (BFD) link bidirectional monitoring, single-pole double-throw isolation, Bypass technology and tunnel technology in communication networks, the key technologies and integration methods to improve the reliability of distribution network were put forward， and the feasibility of the proposed scheme was verified by building a physical simulation environment. The simulation results show that the proposed scheme can be well applied to the complex distribution network, so as to improve its self-healing ability, meet the requirements of physical isolation and service transmission delay, and improve the reliability of the entire distribution network.

To address the issue of large data flow of 5G channel for differential protection of distribution lines， a 5G-based scheme for differential protection for distribution lines considering data flow control is proposed. This scheme optimizes transmission strategy， streamlines data formats， and boosts message efficiency by focusing on the transmission frequency， message content， and message types of differential protection data. Furthermore， it enhances the data synchronization scheme for differential protection and refines the logic for saturation discrimination of current transformer （CT）， significantly reducing data flow without compromising the performance of differential protection. Through experiments， the scheme’s viability for practical applications has been confirmed， offering valuable insights for the real-world deployment of 5G-enabled differential protection for distribution networks.

Although the market for NFT digital products in China is still in its early stages of development, a myriad of young individuals have recently become interested in purchasing the recently trendy virtual clothes. In order to probe deep into the value components of virtual products, the author wishes to utilize virtual clothes as a starting point to examine motivations for purchasing virtual products. On the basis of 35 consumer interviews, this study analyzed and offered nine vital motivations for people purchasing virtual clothes. It summarized these reasons as virtual clothes’ hedonic, social, and functional value. In accordance with the study, enhancing social display and interactive elements should be a top priority to make virtual products trade more popular in the future. This research hopes to optimize the design of virtual products, push NFT digital product market ahead and bring value to practitioners and academics.

Because of their high energy density, high voltage platform, extended cycle life, lack of memory effect, low self-discharge rate, environmental friendliness, and quick charging, lithium-ion batteries, or LIBs, are a vital component of contemporary electronic gadgets. Temperature has a complicated and wide-ranging effect on lithium-ion batteries, though. Lithium-ion batteries will have much-reduced performance, particularly in low-temperature conditions. The total performance of batteries is significantly impacted by the quality and performance of electrolytes in China. In particular, the electrolyte’s purpose in lithium-ion batteries is primarily to convey lithium ions; the battery’s ability to function at low temperatures is greatly influenced by the electrolyte’s ion conductivity and SEI film-forming capabilities. Thus, this article begins by providing an overview of the fundamental composition and properties of lithium-ion batteries. The impact of low-temperature circumstances on lithium ion performance was then discussed. Lastly, many modification techniques were suggested from the electrolyte’s point of view to enhance lithium-ion battery performance in low-temperature settings.

Objective In this study, we aimed to identify long non-coding RNAs (lncRNAs) that play important roles in starvation stress, analyze their functions, and discover potential molecular targets to alleviate starvation stress to provide a theoretical reference for subsequent in-depth research. Methods We generated a piglet starvation stress animal model. Nine Yorkshire weaned piglets were randomly divided into a long-term starvation stress group (starved for 72 h), short-term starvation stress group (starved for 48 h), and the control group. LncRNA libraries were constructed using high-throughput sequencing of piglet ileums. Results We obtained 11,792 lncRNAs, among which, 2,500 lncRNAs were novel. In total, 509 differentially expressed (DE)lncRNAs were identified in this study. Target genes of DElncRNAs were predicted via cis and trans interactions, and functional and pathway analyses were performed. Gene ontology functions and Kyoto encyclopedia of genes and genomes analysis revealed that lncRNA-targeted genes mainly participated in metabolic pathways, cellular processes, immune system processes, digestive systems, and transport activities. To reveal the mechanism underlying starvation stress, the interaction network between lncRNAs and their targets was constructed based on 26 DElncRNAs and 72 DEmRNAs. We performed an interaction network analysis of 121 DElncRNA–DEmRNA pairs with a Pearson correlation coefficient greater than 0.99. Conclusion We found that MSTRG.19894.13, MSTRG.16726.3, and MSTRG.12176.1 might play important roles in starvation stress. This study not only generated a library of enriched lncRNAs in piglets, but its outcomes also provide a strong foundation to screen key lncRNAs involved in starvation stress and a reference for subsequent in-depth research.

The debris flows in the Taihang Mountain region in North China are basically triggered by rainstorms. Firstly, the debris flow susceptibility of the Shaling Gully, Lingshou County, Hebei Province, China was analyzed in this paper to evaluate its hazard and effect on the downstream proposed structures. Secondly, the maximum flow depth and velocity of the potential debris flow in Shaling Gully were numerically simulated based on the FLO-2D model, and the simulation results indicate that the flow depths under the 50-year and 100-year rainstorms will have some effect on the downstream proposed structures. With debris flow intensity classification, the hazard of potential debris flow in Shaling Gully was classified. According to the flow depths and velocities simulated by FLO-2D model, the ARCGIS10.8 software was adopted to optimize the hazard zones, and therefore the hazard zonation map was established. With consideration of simulation results under natural conditions and other factors such as gully feature, a 4 m high and 40 m wide retaining dam was designed. The numerical simulation results show that the retaining dam may decrease the debris flow hazard to a negligible level, which offers some beneficial reference to the subsequent engineering design for Shaling Gully.

Photoelectric properties of all-inorganic perovskite quantum dots (IPQDs) highly depend on their synthetic route. However, current synthetic processes of IPQDs are widely facing potential unsustainable issues of containing nonreusable and high-cost auxiliary materials. In this work, full-visible-spectrum IPQDs were successfully synthesized by an environmentally friendly ion-exchange approach with a renewable and low-cost anion exchange resin. Introducing anion exchange resin brings the improvement of both optical performance and surface morphology of the prepared IPQDs. The emission wavelength of IPQDs can be precisely controlled without changing their inherent crystal phase, and those IPQD’s single crystals with poor morphology and unstable structure are selectively removed. The photoluminescence quantum yield (PLQY) and the fluorescence lifetime of the three-primary-color IPQDs can be dramatically improved to 93.69, 89.99, and 65.03% and 71.3 ns, 22.2 ns, and 13.2 ns, respectively. Notably, the red-emitting PQDs at 622 nm exhibit a record high PLQY. By using the prepared IPQDs for photoluminescent color conversion, the three-primary-color light-emitting diodes (LEDs) provided high brightness and wide color gamut simultaneously. This study provides new ideas for the environmentally friendly and sustainable synthesis route of IPQDs, and it is expected to show great ambitions in the display field.

Abstract Background Salinization damages the health of soil systems and reduces crop yields. Responses of microbial communities to salinized soils and their functional maintenance under high salt stress are valuable scientific problems. Meanwhile, the microbial community of the salinized soil in the plateau environment is less understood. Here, we applied metagenomics technology to reveal the structure and function of microorganisms in salinized soil of the Tibetan Plateau. Results The diversity of composition and function of microbial community in saline soil have changed significantly. The abundances of chemoautotrophic and acidophilic bacteria comprising Rhodanobacter, Acidobacterium, Candidatus Nitrosotalea, and Candidatus Koribacter were significantly higher in saline soil. The potential degradation of organic carbon in the saline soil, as well as the production of NO and N2O via denitrification, and the production of sulfate by sulfur oxidation were significantly higher than the non-saline soil. Both types of soils were rich in genes encoding resistance to environmental stresses (i.e., cold, ultraviolet light, and hypoxia in Tibetan Plateau). The resistance of the soil microbial communities to the saline environment is based on the absorption of K+ as the main mechanism, with cross-protection proteins and absorption buffer molecules as auxiliary mechanisms in our study area. Network analysis showed that functional group comprising chemoautotrophic and acidophilic bacteria had significant positive correlations with electrical conductivity and total sulfur, and significant negative correlations with the total organic carbon, pH, and available nitrogen. The soil moisture, pH, and electrical conductivity are likely to affect the bacterial carbon, nitrogen, and sulfur cycles. Conclusions These results indicate that the specific environment of the Tibetan Plateau and salinization jointly shape the structure and function of the soil bacterial community, and that the bacterial communities respond to complex and harsh living conditions. In addition, environmental feedback probably exacerbates greenhouse gas emissions and accelerates the reduction in the soil pH. This study will provide insights into the microbial responses to soil salinization and the potential ecological risks in the special plateau environment.

Understanding the spatial distribution pattern, species characteristics of moss taxa, and their relationship with heavy metals is important for biodiversity conservation and heavy metals pollution management in manganese mining areas. Characteristics of moss species in four functional areas, including, Mine entrance, Waste rock area, Transportation line, Manganese ore storage, were explored using abundance index, α diversity indices, and β diversity indices. Distance-based Redundancy Analysis was used to explore the relationship between changes in moss β-diversity and soil heavy metals. Multivariate-Regression-Trees were used to determine moss indicator species. A total of 22 species of mosses, comprising 14 genera from 7 families, were identified in the study area. The most dominant families were Bryaceae and Pottiaceae. Soil heavy metals were significantly affected species diversity, species replacement (R2adj = 0.495, P = 0.001), and species richness (R2adj = 0.667, P = 0.001). In functional areas with low levels of heavy metals, moss species diversity was high, probability of species replacement was low, and variation in species richness was low. On the contrary, in functional areas with high heavy metal content, moss species diversity was low, probability of species replacement was high, and variation of species richness was high. The classification results of the sampling plots showed presence of six indicator species (Brachymeniopsis gymnostoma, Funaria attenuata, Trichostomum brachydontium, Encalypta ciliata, Molendoa sendtneriana, and Plagiobryum zieri) in the Mine entrance whereas no indicator species were observed in the Transport line. In addition, only one indicator species (Barbula subcontorta) was observed in the Waste rock area, and five indicator species (Bryum blindii, Physcomitrium repandum, Philonotis secunda, Brachymenium exile, and Syrrhopodon prolifer) were present in the Manganese ore storage. These findings show that more indicator species occur in areas with relatively high or low heavy metals content, whereas fewer indicator species occur in areas with relatively moderate-heavy metals content.

BACKGROUND Accelerator mass spectrometry (AMS) is the most popular technique for radiocarbon analysis. However, yielding high precision and low background 14C data by AMS is hindered by sample preparation. Therefore, improving the stability of graphitization and reducing the carbon contamination in the background helps to produce high quality 14C data and break through the 14C dating upper limit (about 50000ya), further broadening the application range of 14C chronology and isotope tracer. OBJECTIVES To provide basic reference for beginners or more experienced scientists who are going to set up a radiocarbon sample preparation vacuum line and methods. METHODS The development of graphite preparation technology with respect to sample preparation vacuum line apparatus and the underlying principle of H2/Fe, Zn/Fe and Zn-TiH2/Fe methods were reviewed. The advantages and drawbacks of these methods were also discussed. Additionally, the optimization of experimental conditions from the perspective of reductant, catalyst and graphitization temperature, accompanied by the inner relationship with the graphite yield, isotope fractionation and beam performance were emphatically discussed. The sources of carbon contamination and suitable control technology were also argued. RESULTS The optimized graphitization conditions by H2/Fe method was H2/CO2=2-2.5 (V/V), -325 meshes ion powder derived from hydrogen reduction with Fe/C=2-5 (m/m), and graphitization temperature of 500-550℃, while by Zn/Fe method it was Zn/C=50-80 (m/m), -325 meshes ion powder derived from hydrogen reduction with Fe/C=2-5 (m/m), and graphitization temperature of 400-450℃ for Zn reaction tube and 500-550℃ for Fe reaction tube. The carbon contamination originated from each step in the sample preparation procedure, which could be either reduced by high-temperature bake or calibrated by mathematical model, but it required more detailed study to strengthen our knowledge and eliminate the effects on results. CONCLUSIONS Both of the sample preparation methods used and the optimum of graphitization conditions are critical for good performance of the graphite target and the final precision and accuracy of the measurement, especially for ultra-small size samples. However, these effects could be reduced or even eliminated by optimizing the experimental procedures and the graphitization conditions or subtracting by mathematical models.

BACKGROUND The technical keys of high-quality 14C-Accelerator Mass Spectrometry (AMS) analysis with low-background is the sample preparation method and the vacuum line rigs. However, the development of the graphite target preparation method is impeded by extraneous source carbon contamination, unsteady graphitization yield and isotope fractionation. OBJECTIVES To reduce the requirement of the traditional on-line method on the long-term statical vacuum performance of the sample preparation line, solve the problem of CH4 produced in the Zn-TiH2/Fe sealed tube method, while improving the stability of graphitization, and control carbon contamination. METHODS 14C sample preparation vacuum system and graphite preparation method based on Zn/Fe flame sealing method was established. The effects on the beam current and values of graphite (prepared from OXⅡ and blank samples) between the Zn/Fe on-line method and the Zn/Fe flame sealed tube method were compared. The precision of the Zn/Fe flame sealed tube method was checked with OXⅡ as the unknown sample. Two 'in-house' blank standards IHEG-Cal and IHEG-Coal were used to evaluate the chemical procedure background of both methods. The other 'known-value' reference materials of IAEA C2, C3, C5, C7, C8 and C9 were used to validate the accuracy of the Zn/Fe flame sealed tube method. RESULTS Zn/Fe on-line method can obviously overcome the air leakage, which yields a lower chemical process background (0.24-0.32pMC) and higher ultimate radiocarbon age (47000-48000ya) observed in Zn/Fe flame sealed tube method with long-term stable beam current output. It was demonstrated that Zn/Fe sealed tube method was more suitable for graphite target preparation than Zn/Fe on-line method. The results illustrated that the Zn/Fe flame sealed tube method had good reproducibility (RSD=0.35%, n=20, OXⅡ), and high accuracy for a variety of natural samples ranging from dead carbon samples to modern carbon samples (linear fitting formula y=0.9969x+0.0013, R2=1) with a low background (radiocarbon age of blank 46296±271ya for inorganic carbon and 48341±356ya for organic carbon). CONCLUSIONS The graphite sample preparation vacuum system and the Zn/Fe flame sealing method have the characteristics of excellent graphite quality, low chemical procedure background, high accuracy and high precision, and meet the sample preparation requirements of high-precision and low-background 14C-AMS determination for graphite.

In view of problem that magnetic signal propagation had significant directionality, but effect of antenna position and angle on transmission performance in magnetic communication had not been fully considered by current researches, magnetic signal transmission characteristics of three kinds of antenna models of underground magnetic induction communication were researched including double-coil array and four-coil array in 2D antenna array and 3D coil model. Firstly, expressions of corresponding magnetic induction intensity and mutual inductance between sending coil and receiving coil were given according to mathematical models of the three antennas. Secondly, magnetic induction intensity was simulated and analyzed. Position and angle of receiving antenna were optimized according to magnetic field distribution. Finally, transmission performances of the three antenna models were compared, and influences of offset of each sending coil and vertical distance between sending coil plane and receiving coil plane on magnetic induction intensity were given. The research results are as follows: ① Magnetic induction intensity of 2D antenna array model and 3D coil model has symmetry and directionality. ② Transmission direction of 2D antenna array model changes from multiple directions to one direction as the vertical distance increases. ③ When parameters of sending coils are as the same, transmission distance of 2D antenna array model is greater than that of point-to-point communication system and 3D coil model. The more the number of sending coils, the farther transmission distance of 2D antenna array model is. But magnetic induction intensity rapidly decreases as the vertical distance increases. ④ 3D coil model has the same distribution of magnetic induction intensity in three coordinate axes. Magnetic field of 3D coil model is the most widely distributed, but norm of magnetic induction intensity is less than the one of 2D antenna array model.

How to scientifically reflect the soil environmental quality of a large area through limited soil point monitoring is a major direction of current research. The Huaihe River Basin in Anhui Province was selected as the study area and soil environmental quality monitoring for five major soil pollution types during five consecutive years was conducted. The monitoring project includes Cd, Hg, As, Pb, Cr, Cu, Zn and Ni in the soil. The single pollution index and Nemerow pollution index methods were used to evaluate 426 monitoring sites. The Kriging interpolation method was used to plot the distribution of heavy metal elements in regional soil. In general, the soil environmental quality of the Anhui section of the Huaihe River Basin is relatively safe according to the evaluation results. 96.48% of the surveyed sites belong to clean and relatively clean levels, but some sites were severe. According to the distribution of heavy metal elements in the evaluation area, the overall content is low and the local area is slightly higher. The method of special type monitoring was applied and the characteristics of regional distribution through soil point monitoring results are discussed. The proposed method has great application potential. This method is suitable for preliminary investigation and research of large-scale environmental quality of soil.

The research measures the driving force of innovation in economic structure transition. In order to change the pattern of economic development, China is implementing a strategy of innovation-driven development. China’s capacity of innovation has been increasing, especially since 2012, and China’s innovations have taken a leap-forward development. Nowadays, innovation has become a main driving force in China’s economic development and hi-tech industries particularly make a great contribution. Although China’s tertiary industry has been dominant and its share in three industrial sectors has been exceeding 50% since 2015, a problem still exists in China’s economy that the proportions of primary and secondary industries are relatively higher compared with developed countries. In this paper we use PLSR model to measure the impact of innovation on China’s economic structure transition. It is found that innovation can expand the tertiary industry through shrinking the proportions of primary and secondary industries, transforming China’s economic structure into a more advanced pattern. Additionally, China is also devoting itself to the “Belt and Road Initiative”, which should be combined with China’s domestic innovation-driven development and realize sustainable development of economy worldwide.

Research status of existing wireless through-the-earth communication was comprehensively analyzed, performances of ground electrode, elastic wave and magnetic induction communication were compared, and result was got that performance of the magnetic induction communication is better than the other two kinds of communication methods. The magnetic induction communication model was emphasized, and on this basis, key technical problems and feasible solutions of the magnetic communication were put forward. Besides, design schemes of existing magnetic communication transmitter and receiver were elaborated. The future research directions of through-the-earth communication was put forward considering current studies and popular applications: large magnetic signal fading is a key factor which restricts further development of the magnetic induction communication; transmitter, receiver and transmission mechanisms of the magnetic induction communication need to be improved; through-the-earth communication system used in underground mine not only needs to control transmission power in safety range, consider compromise relationship between communication distance and transmission power, but also needs to consider how to suppress complex underground electromagnetic interference.

Identification of porosity in shale is of great significance for exploring mechanism of shale gas. Porosity properties of the shale samples from the Ordos Basin were characterized by multiple techniques including Scanning Electron Microscope(SEM), Mercury Intrusion Porosimetry(MIP), and nitrogen gas adsorption-desorption. Results showed that the shales contained abundant pores that include dissolution pore, microfracture pore, and intergranular pore. The pore sizes range from several to several hundred nanometers. The total surface area ranges from 5.06 to 19.32 m2/g and pore volume has a range of 0.01-0.03 cm3/g. Results indicate that the OrdosBasin Shale develops pores of various types and sizes. The main type of pore is the nano-pore, which is beneficial for the storage of shale gas. Micro-cracks are beneficial for the transportation of shale gas. These results suggest that the basic environment of the Ordos Basin is suitable for the storage of shale gas and that the Ordos Basin may be rich in shale gas.