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[Introduction] In order to test the applicability of sea surface wind field data set in Yangjiang offshore wind farm area, this paper tests and evaluates the 10 m wind field of daily gridded advanced scatterometer (DASCAT), European centre for medium-range weather forecasts reanalysis v5 (ERA5) and final reanalysis data (FNL). [Method] The research was based on the 10 m wind fields at four sites in the Yangjiang offshore wind farm area in Guangdong province. [Result] The results demonstrate five pionts: (1) The wind speed correlations are above 0.8, with ERA5 the highest. The RMSE of wind speed are within 2.6 m/s, with DASCAT being the best in SWZ and ERA5 being the best in DWZ. Both FNL and ERA5 show significant underestimation of wind speed in SWZ, while DASCAT has smaller mean wind speed deviation than those of FNL and ERA5, and ERA5 mean wind speed is closer to those of observation. (2) The wind direction correlation reaches more than 0.75, with ERA5 being the highest in SWZ and FNL being the highest in DWZ. The RMSE of wind direction are within 35°, and ERA5 errors are the minimum. However, DASCAT and FNL are both closer to the observed predominant wind direction. (3) The statistics of the RMSE of wind speed in each wind speed period show that FNL is the minimum in the low wind speed period while DASCAT is the minimum in the medium and high wind speed periods in SWZ. ERA5 is the minimum in all wind speed period in DWZ. In both SWZ and DWZ, ERA5 has the highest wind speed correlation in both the low and medium wind speed periods, and FNL has the highest wind speed correlation in the high wind speed period. (4) The monthly wind speed errors of DASCAT and ERA5 are small and distributed relatively close to each other in SWZ, with peaks in April-May and October; ERA5 errors are smallest in DWZ, with a peak in July and a trough in December-January of the following year. (5) The distribution characteristics of the multi-year average wind speed for 10 m show that the wind speed increases from north to south and from west to east, and the wind speed gradient is large in SWZ. [Conclusion] Overall, the 10 m sea surface wind field data set of ERA5 performs better in the study area, and the deficiency of its systematic low mean wind speed can be corrected by DASCAT.

In order to reduce the cost of roadside filling and ensure the stability of the retained roadway system, the 150202 fully mechanized mining face of Shenlei Coal Mine is taken as the background, and the roadside filling body is made of coal gangue and fly ash as the base material, through orthogonal experiments, theoretical analysis, numerical simulation, on-site measurement and other research methods, the optimal ratio of filling materials and the laws of yield stress and deformation of roadway surrounding rock with different filling widths are studied. The results show that the optimal ratio of gangue filling body is water cement ratio 1∶1.85, fly ash replacement cement ratio of 20%, fine coarse aggregate ratio of 35∶65, and sodium silicate content of 6%; the larger the width of the roadside filling body next to the gob-side entry retaining, the lower the deformation of the surrounding rock and the vertical stress of the coal wall; by comprehensively comparing the stress and displacement of surrounding rock under different widths, it is concluded that the reasonable width of the roadside filling body next to gob-side entry retaining is 1.2 m.

Immunotherapy, represented by immune checkpoint inhibitors, may lead to immune-related adverse events (irAEs) while demonstrating favorable efficacy in patients with malignant tumors. Many domestic and international guidelines or consensus have been established to assist clinicians in effectively managing the majority of irAEs. However, further exploration about irAEs is required regarding the definition and determination, temporal patterns, individual variances, utilization of hormones and immunosuppressants, correlation between irAEs and therapeutic outcomes, immune reactivation, and special populations. The identification and management of severe, refractory, and multiple irAEs necessitate additional solutions. This paper aims to clarify 10 prominent issues concerning irAEs individually and provide assistance for clinicians.

In this work, molten salt method was used to prepare highly dispersed graphitic carbon nitride(WSGCN), and chemical reduction method was used to load Cu nanoparticles on WSGCN to prepare Cu-WSGCN composites. FTIR, XRD, XPS, TEM, SEM, ICP-AES, UV-vis DRS, PL spectroscopy, ESR and EIS characterization methods were carried out to investigate the structure and photoelectric properties of the photocatalyst. The results show that compared with WSGCN, Cu-WSGCN has a larger light absorption range and a narrower band gap. In addition, the presence of Schottky barriers at the interface between Cu nanoparticles and WSGCN promotes charge transfer and separation of photogenerated carriers, which improves the photocatalytic ability. The uranium removal rate of Cu-WSGCN composite is relatively high(81.07 %) when the load of Cu nanoparticles is 1%. After three cycles of photocatalytic uranium reduction experiments, the uranium removal rate by 1%Cu-WSGCN can still reach 75.96%, which provides a useful reference for the development of novel materials with high efficiency photocatalytic removal of uranium.

In order to optimize the fermentation process conditions of mulberry leaf tea and explore the changes in antioxidant activity of mulberry leaf tea after fermentation. This experiment used response surface analysis to determine the optimal process conditions for fermenting mulberry leaf tea under three variable conditions: Fermentation temperature, fermentation time, and inoculation amount of Aspergillus niger. The content of bioactive substances and antioxidant properties in fermented mulberry leaf tea were determinated. The findings indicated that 5 days and 16 hours of fermentation duration, 30 ℃ of fermentation temperature, and 16.55% of inoculation amount were the ideal process parameters, and that the fermented mulberry leaf tea scored as high as 90 on the sensory scale under these conditions. In addition, the content of total flavonoids, total polysaccharides, polyphenols, free amino acids, rutin, and quercetin in fermented mulberry leaf tea increased by 14.39%, 12.67%, 2.90%, 3.46%, 81.13%, and 19.35%, respectively, compared to mulberry leaf green tea. Tea brown pigment with a content of 7.55%±0.37% was also detected in fermented mulberry leaf tea. In addition, the scavenging rate of hydroxyl radicals, DPPH radicals, superoxide radicals and the chelating rate of divalent iron ions of fermented mulberry leaf tea at the concentration of 1/1000 (g/mL) were 1.16, 1.07, 1.06 and 0.82 times higher than that of mulberry leaf green tea, respectively. The results of this study provide theoretical basis and references for further development and application of mulberry leaf in the future.

In order to sort out the research process and hotspots of honey safety, this paper was based on the China national knowledge infrastructure (CNKI) database and the Web of Science (WOS) core collection, utilizing CiteSpace software to analyze and visualize publication trends, journals, authors, institutions, countries (regions), keywords, and other relevant information. The aforementioned databases yielded a total of 169 Chinese and 281 English literatures. The analysis revealed that the number of publications in Chinese literature on honey safety had been steadily increasing since 2011. The number of publications in English literature had displayed an oscillating upward trend since 2007, with a higher volume of publications in English literature over the past fifteen years compared to Chinese literature. ZHANG Q and GUNDUZ A were the most prolific authors in Chinese and English literature, respectively. While there were established cooperative relationships between researchers in both fields, collaborations between different groups remained relatively limited. Journal of Bee and Food Chemistry were the leading journals for publications on honey safety in English and Chinese, respectively. Both English and Chinese publishing journals primarily focused on the food industry. Yunnan Province Center for Disease Control and Prevention and Karadeniz Technical University were the research institutions with the highest publication output in Chinese and English, respectively. However, there was limited collaboration between research institutes in China. Turkey was the most influential country among the study countries (regions), followed by China, Poland, and New Zealand. During the initial stages of research, Chinese literature primarily explored topics such as "botulinum toxin" "pollen plants" "Triperygium wilfordii Hook. f." and "honey poisoning". However, after 2000, advancements in technologies such as chromatography, spectroscopy, and scanning electron microscopy led to the emergence of new keywords like "melissopalynology" and "gas chromatography". Consequently, gas chromatography, liquid chromatography, liquid-mass spectrometry, and scanning electron microscopy gained popularity as methods for detecting honey safety in research. During the early stages of research, English literature primarily delved into topics such as "pyrrolizidine alkaloids" "mad honey" "grayanotoxin" and "natural toxicants". This indicates that during this time, the primary emphasis was on studying toxic honey and natural toxins found in honey, specifically pyrrolizidine alkaloids and grayanotoxin. As technologies such as chromatography advanced, keywords like "mass spectrometry" began to emerge. It could be seen that the research in Chinese and English literature was focused on similar topics, such as toxic honey, honey poisoning, and the detection and tracing of toxic components in honey. However, there were slight differences in emphasis. In China, the main toxic nectar plants were Triperygium wilfordii Hook. f., Gelsemium elegans (Gardn. & Champ.) Benth. and Macleaya cordata (Willd.) R. Br., while the main toxic components detected in honey were triptolide and koumine. In foreign countries, honey poisoning incidents were mostly caused by grayanotoxin, pyrrolizidine alkaloids or tutin. This study provides reference for analyzing the research content and development process of honey safety and identifying research hotspots.

To optimize the resource utilization of walnut green husk and investigate the impact of grinding treatment on walnut green husk powder, this experiment was carried out to investigate the physical characteristics (particle size distribution, filling, flowability, water-holding capacity, oil-holding capacity, swelling capacity, and microstructure) and functional characteristics (active substance content, and antioxidant activity) in walnut green husk powders with varying particle sizes. The results demonstrated that the particle size of walnut green husk powder exhibited a significant difference (P

In order to study the effective method of the enrichment and purification of anthocyanin in black wolfberry and mulberry, and identify the structure of anthocyanin, the black wolfberry and mulberry extracts were purified by macroporous resins. The adsorption and desorption abilities of different types of the resins for anthocyanins were compared. LX-20SS was optimized as the resin for the purification of anthocyanins from black wolfberry. The purification conditions were as follows: The mass ratio of resin to crude anthocyanin powder of black wolfberry was at 10:1, and the elution concentration of ethanol was 70%, and the flow rate was 3 mL/min. After the purification, the content of anthocyanin reached 144.18±3.40 mg/g. DM-21 was optimized as the resin for the purification of mulberry anthocyanin. The purification conditions were as follows: The mass ratio of resin to crude anthocyanin powder of mulberry was at 20:3, and the elution concentration of ethanol was 30%, and the flow rate was 1 mL/min. The content of anthocyanin reached 112.44±2.24 mg/g after purification. High performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) analysis for anthocyanin structures in black wolfberry and mulberry showed that the main anthocyanin in black wolfberry was petunidin-3-O-rutinose (p-coumaroyl)-5-O-glucoside, which accounted for more than 95% of the total anthocyanin. In addition, there are two main types of anthocyanins in mulberry, corresponding to cyanidin-3-glucoside and cyanidin-3-rutinoside, which accounted for 63.58% and 36.42% of the total anthocyanins respectively. The results provided references for the development of black wolfberry and mulberry.

The occurrence mechanism of coal and gas outburst disasters is still unclear. According to the rheological hypothesis, gas-bearing coal and rock may enter the “strength limit neighborhood” under long-term load, and it is more likely to be destroyed by external impact disturbance. The “strength limit neighborhood” of gas-bearing coal rock under different loading conditions is studied to find the influence law of entering this state, and the corresponding micro-discrimination criteria are established,” using the self-developed triaxial test system of rock rheological disturbance effect and the seepage experimental device of coal rock rheological disturbance effect, the rheological disturbance experiment of gas-bearing coal rock under different confining pressures, different gas pressures and axial pressures was carried out. The coal rock before and after rheological disturbance was analyzed and compared by means of nuclear magnetic resonance, and the T2 spectrum curve, porosity and pore size distribution under different loading conditions were obtained. The test results show that: ① In the rheological process of coal rock under different loading conditions, there is a critical value for the sensitivity of external disturbance. When the applied force is less than this critical value, after the impact disturbance, the porosity of coal rock decreases and the specimen is compressed closely. When the force is greater than this critical value, after the impact disturbance, the large pore size of coal rock increases obviously, the T2 spectrum curve shifts to the right, and the peak height increases, It shows that the stress threshold is the key to determine whether the coal rock enters the “strength limit neighborhood”. ② Confining pressure and gas pressure have opposite mechanical properties to coal rock. It is shown in the compressive capacity, damage degree, long-term strength and “strength limit neighborhood”. Among them, the greater the confining pressure, the earlier the coal rock enters the “strength limit neighborhood;” The greater the gas pressure, The greater the gas pressure, the earlier the coal rock enters the neighborhood. ③ the pore size distribution and T2 spectrum curve of coal rock can directly reflect the internal and external micro-variation characteristics of rock’s “strength limit neighborhood.” ④The constitutive equation of axial pressure, confining pressure and gas pressure determined by the porosity of coal rock can be used to judge the timing of coal rock entering the “strength limit neighborhood” under different loading conditions. As a criterion for entering the “strength limit neighborhood,” the greater the confining pressure, the greater the stress threshold when entering the “strength limit neighborhood,” the greater the gas pressure, and the smaller the stress threshold when entering the “strength limit neighborhood.”

ObjectiveThe study in this paper aims to investigate the impacts of cabin atmosphere quality on the comfort and the work efficiency of crew member aboard the ship, thereby the degree of thermal comfort of ship air conditioning system can be improved.MethodAirpak software is used to simulate and analyze the temperature, relative humidity, PMV-PPD and air age in the four air supply and return modes of a typical single-occupant cabin of a ship, namely ‘different side up and down cycles’, ‘same side up and down cycles’, ‘different side down and up cycles’, and ‘same side down and up cycles’. ResultsThe simulation results show that the temperature in the cabin can be kept constant at 24℃, humidity can be maintained at about 50% and the humidity field distribution can be more uniform, while PMV (predicted mean vote) distribution is more uniform with its value tending to zero, and the air age PPD (predicted percentage of dissatisfied) distribution is more uniform with a very low value in the cabin.ConclusionUsing the optimization principle of lattice order theory, the air supply and return mode of ‘different side up and down cycles’ is the optimal scheme for a single-occupant cabin of a ship.

Starch was the main source of carbohydrates in people's daily diet, and its digestibility was an important factor affecting the body's postprandial blood glucose level. In this paper, the effect of xylose on the in vitro digestive properties of corn starch and its mechanism of action were investigated. The in vitro digestibility of starch was evaluated by an in vitro simulated digestion system after different additions of xylose (5%, 10%, and 15%), and the mechanisms of xylose on α-amylase and α-glucosidase, as well as its effect on blood glucose fluctuation through enzyme inhibition kinetics, molecular docking, and human glycemic index (GI) tests. The results showed that the digestive hydrolysis of corn starch was inhibited by different amounts of xylose, and the IC50 values of xylose on α-glucosidase and α-amylase were 205.35 and 4.75 mg/mL, respectively, which belonged to the mixed type inhibitors. Xylose interacted with amino acid residues of α-glucosidase and α-amylase through hydrogen bonding with binding energies of −3.05 and −5.30 kcal/mol, respectively. Additionally, the GI value of plant-based peptidoglycan milk decreased from 58 to 45 after the addition of xylose, which demonstrated that xylose was effective in decreasing the fluctuation of postprandial blood glucose. The results could provide scientific data to support the research and application of xylose in nutritional and health foods.

ObjectiveTo analyze the prevalence of pertussis in Hangzhou city from 2010 to 2022 and predict its incidence rate using an autoregressive integrated moving average (ARIMA) model, with the goal of improving prevention and control measures. MethodsThe reported pertussis incidence data and population data of Hangzhou city from 2010 to 2022 were collected through the infectious disease surveillance system in the Chinese Disease Prevention and Control Information System and the Statistical Yearbooks published by the Hangzhou Statistics Bureau (http://tjj.hangzhou.gov.cn/), respectively, to analyze the epidemiological characteristics. The collected data was used to construct an ARIMA model for predicting pertussis incidence rates in the city for 2023 and 2024. ResultsA total of 2 484 pertussis cases were reported in Hangzhou city over a 13-year period, with a male-to-female ratio of 1.03 : 1 and an average annual incidence rate of 2.49 per 100 000 population. The majority of pertussis cases occurred during the summer season, with the highest monthly incidence observed in June each year. Three districts within the city exhibited high rates of pertussis incidence. Approximately half (47.34%) of the reported cases involved children aged 0 – 4 years old. Based on the optimal ARIMA(0,1,2)(0,1,1)12 model analysis results, a projected decrease in annual incidence rates is expected for both 2023 and 2024 compared to that of 2022. ConclusionThe incidence of pertussis in Hangzhou has been increasing from 2010 to 2022, and the ARIMA model can provide predictions for the incidence trend of pertussis in the city.

The integration of underground coal gasification (UCG) and carbon emission reduction is expected to become an excellent green energy technology during the transitional stage from the current to the arrival of carbon neutrality, and even play an important role in the longer history of carbon neutrality in the future. Looking back at the research history and current situation, the systematic strategy for UCG emission reduction has been basically formed, which can be summarized into five specific approaches. Among them, the targeted underground in-situ regulation can reduce the CO2 release and promote the quality and yield increase of UCG synthesis gas, and the relevant strategies and approaches can be summarized as the Carbon Regulation and Reduction (CRR). There are many research achievements on the supercritical gas storage of UCG-CO2 in underground space, mainly focusing on storage media, storage space, storage capacity, etc., with some discussions for storage mechanisms. The mineralization and storage of UCG-CO2 in underground space are not constrained by the harsh conditions of geological stability and sealing, and there is a potential dual effect of both carbon sequestration and gas conversion, but there are not many research results yet. The previous exploration of UCG-CO2 reinjection, utilization and storage focuses on two aspects, such as enhancing coalbed methane production and improving the production of UCG synthesis gas, and a series of explorations have been initiated for the emission reduction and utilization of CO2 from the tail gas of UCG hydrogen production in recent years. The CRR, as an active emission reduction strategy, targetedly reduces the CO2 concentration in the UCG synthesis gas by adjusting the gasifying agent and its injection method, and there are many theoretical achievements and preliminary on-site verification, which are expected to become a practical clean coal technology that integrates clean energy production and carbon reduction. Reviewing the progress and analyzing the shortcomings, the scientific and technological research for UCG carbon emission reduction has made many substantial achievements, but also still faces some challenges of sustainable development, and the future study should focus on four aspects. One is to prioritize the development of UCG-CO2 underground conversion and utilization technology with a focus on the UCG-CRR based on feasibility. The second is to focus on the shortcomings and to strive for the breakthrough of the collaborative mechanism and key technological bottlenecks of both UCG emission reduction and synthesis gas quality improvement. The third is to make solid progess and promote the prior implementation of UCG-CRR pilot tests and engineering demonstrations for the achievement of practical results step by step. The fourth is to ensure the implementation and establishment of the “trinity” policy support system for the UCG emission reduction consisting of carbon neutrality and management strategy, special science and technology action plans, and professional talent training.

In the ever-changing marine environment, the key to the optimal design of the towed cable and the precise control of the towed body in the underwater towing system is the quantification of uncertainty at the end of the towed cable. The Monte Carlo(MC) method, a traditional uncertainty quantification method, has high computation costs and low accuracy. In view of this, a method of uncertainty quantization at the end of a towed cable based on polynomial chaos(PC) was proposed. Latin hypercube sampling was used to obtain sample sets of the towed cable parameters, and the sample sets were substituted into the lumped-mass method model to obtain the coordinate of the end position of the towed cable. A proxy model of the end response of the towed cable was generated by the PC method, and the uncertainty of the end was quantified according to the characteristics of the orthogonal polynomials. At the same time, the results of the PC method were compared with those of the MC method. The results show that compared with the MC method, the PC method has a faster convergence speed in terms of sample size and higher accuracy. The uncertainty of motion response is approximately proportional to the axial length of the towed cable; the increase in cable length leads to the increase in uncertainty at the end, and the increasing trend is gradually flattened. When the uncertainty of the towed cable parameters is constant, increasing the speed of the mother ship helps to improve the stability of the towed body at height. The accuracy and efficiency of the PC method have been verified. Meanwhile, the quantitative analysis results of the uncertainty at the end of the towed cable guide engineering problems.

The security of underwater acoustic communication networks is an important guarantee for information sharing and cooperative operation of underwater communication. Existing technologies mainly study authentication protocol and data encryption, focusing on improving the security of the network but ignoring the efficiency and energy consumption of the network. To avoid network congestion caused by the above methods, this paper, inspired by research in mobile smart devices and other fields, proposed to integrate voiceprint authentication into the identity authentication system of underwater communication networks, and it designed a recognition method based on voiceprint features of communication payloads. This method used the attention mechanism and merged nonlinear cepstrum features and phase spectrum features to reduce the influence of complex marine environment noise. In addition, it identified the target through the AlexNet network. To verify the effectiveness of this method, this paper collected underwater acoustic communication signals, verified the difference and effectiveness of the proposed voiceprint feature recognition, and demonstrated the feasibility and reliability of the proposed method. The research in the paper provides a new idea for solving the identity authentication of underwater acoustic communication networks, which serves as a reference for enhancing security and realizing high-quality information sharing and high-efficiency cooperative control of underwater acoustic communication networks.

ObjectiveTarget tracking is an important application of unmanned surface vehicles (USVs). This study proposes a relative time-varying tracking position (RTTP) strategy to improve the tracking stability and address the problem that the reference trajectory obtained by the relative fixed tracking position (RFTP) strategy contains inflection points and leads to tracking instability.MethodsA first-order hysteresis filter is used to process the target USV's heading variation. The time-varying tracking position is then designed according to the filtered data, the target tracking problem is transformed into a trajectory tracking problem and the reference trajectory is obtained. Finally, model predictive control (MPC) is used to achieve the tracking of the target USV.ResultsThe simulation experimental results show that the tracking effect of the USV under the RTTP strategy is more stable with the root mean square error (RMSE) of the tracking distance decreased by 28.06% and the energy consumption reduced by 5.93%. It also has advantages in the smoothness of the control volume.ConclusionsCompared with the traditional RFTP strategy, the proposed RTTP strategy can effectively improve the stability of USV target tracking, giving it practical significance for the target tracking of USVs.

The Bohai Bay Basin is one of the key areas for the exploration of buried hill oil and gas resources in China. In order to create a new prospect for the exploration of the Archaean buried hills in this area, the reservoir-forming laws and main controlling factors of the Archaean buried hill reservoir in the Liaodong Bay area were studied. Based on drilling data such as stratum, logging, and seismic data, this paper classified the lithology and distribution patterns of Archean buried hills in the Liaodong Bay area, and analyzed the dominant reservoir space types and controlling factors. The results show that the Archean buried hills in the Liaodong Bay area are composed of schist, metamorphic granite and cataclastic rocks, with schist being the predominant lithology. The current structure is high in the south and low in the north. The strata are relatively intact in the north, while the upper part of the strata in the south shows evidence of denudation. The proportion of igneous rocks increases gradually from north to south. The metamorphic rocks are dominated by fracture reservoirs. The content of mafic minerals is inversely correlated with the brittleness of rocks. Tectonic deformation led to fracture development. Three sets of structural fractures were developed in the Archean buried hills of the Bohai Bay Basin, i.e., NNE shear fractures and SN tensile fractures were developed in the stress directions of NE strong shear and SN strong compression in the early Yanshanian period, NE shear fractures and NE tensile fractures were developed in the stress directions of NW strong extension and NE weak shear in the early Himalayan period, and EW tensile fractures and NE and NW conjugate shear fractures were developed in the stress directions of NE strong shear and NW weak extension in the late Himalayan period. The degree of regional tectonic activity controlled the effectiveness of the fractures. The Yanshanian movement was the main stage of fracture formation in metamorphic rock reservoirs. During the Himalayan period, fractures were mainly filled and semi-filled with calcite, and effective fractures could be formed through dissolution in the later stage.

The low security and poor privacy of the data in edge computing restrict the development of edge computing.Block chains can provide security for data in edge computing using their own tamper resistance, while protecting privacy by use of traceability.But the bottleneck of blockchain's scalability has become a barrier to their application in the field of edge computing.To solve the problem that blockchain can not meet the needs of a large number of nodes to process data at the same time when applied to edge computing, a two-layer sharding scheme was presented, which meets the needs of edge computing scenarios.Geographic location-based partitioning of nodes was implemented using the improved K-means algorithm, and a local blockchain network consensus (LBNC) algorithm was designed based on the idea of delegated proof of stake (DPoS) and practical Byzantine fault tolerance (PBFT).Simulation results show that the proposed scheme has less delay and higher throughput than those of PBFT, and the total throughput increases with the number of shards.

In order to meet the unmanned needs of thin coal seam fully mechanized mining faces and address the issue of requiring dedicated personnel to monitor the cables of existing coal mining machines, an automatic cable dragging system for coal mining machines has been designed, The system has a rated power of 15 kW, a maximum length of 400m for the working face, and is suitable for a maximum speed of 30 m/min, This article focuses on the overall design, parameter design, and adaptation design of the automatic cable dragging system for coal mining machines, It elaborates in detail on four key technologies: the design of the cable chain transmission system based on dynamic simulation analysis, the track floating alignment technology suitable for complex working faces, the self adaptive control technology based on speed and torque, and the fast cable disassembly and assembly technology. The system design, mechanical structure, control strategy, fault protection, and other difficulties have been solved, It solves the problems of system design, mechanical structure, control strategy, and fault protection, and achieves that the cable clamp is always in a slightly tensioned state, Engineering application was carried out in the 14301 working face of Zhangjiamao Coal Mine, achieving adaptive and normalized operation of the entire working face, with a follow-up rate of 94.7%, The system has a reasonable structure, high reliability, convenient disassembly and maintenance, and can be retrofitted on existing working faces, It has strong scalability and promotes the progress of unmanned mining technology in thin coal seams.

This is an essay in the field of mining engineering. In the current new energy development strategy under the new situation, lithium is an indispensable key raw material to support the development of the new energy vehicle industry and promote the new energy revolution. It is positioned as one of China's 24 national strategic mineral resources, and its strategic position is extremely important. The safety of lithium resources and the continuous supply of lithium mineral products are related to the healthy and stable development of many industries and the national economy in China. China is rich in lithium resources. However as the world's largest consumer of lithium resources and producer of lithium batteries, lithium is highly dependent on foreign countries, and there are hidden dangers in the supply system. It is urgent to improve the safety and security of China's lithium resources. Based on the combing and research on the distribution of lithium resources at home and abroad and the supply and demand situation of lithium mineral products, this paper analyzes and elaborates on the main problems and causes faced by China's lithium resources. This paper analyzes the main problems faced by China's lithium resources and their causes, and puts forward opinions and suggestions on the development and utilization, scientific and technological research, industrial structure, institutional mechanism, personnel construction, market regulation, overseas strategy and other aspects in order to increase production of lithium resources and maintain supply and stability, which provides useful reference for ensuring the safety and stability of China's lithium resources and the healthy and orderly development of lithium mining industry.

Marine stock enhancement is not only commonly reported to amplify the target species production but also induces some potential threats or effects at multiple ecological levels in the receiving ecosystem. Studies on the interaction between released and naturally occurring organisms are necessary to avoid or minimize the adverse impacts of invasive species from stock enhancement in the receiving system. Chinese shrimp Fenneropenaeus chinensis, are an important stock enhancement species, and in recent years approximately 10 billion have been released annually into the coastal waters of China. Owing to fishing pressure and the ecological complexity of the open sea, the interaction between the released shrimp and native species may be weak and undetectable. Studies on the ecological impacts of such intensive releasing activities are limited. Therefore, in this study, an in-situ mesocosm experiment was carried out to determine if the released shrimp altered the relative composition and niche characteristics of fish, the results of which could serve as a reference to the local risk management of the species stock enhancement. The mesocosm was located in the shrimp-releasing channel of Weihe, Laizhou Bay, from April to September 2019. A cross design of four treatments with three replicates was conducted in the mesocosm. The habitats were homogenized across the replicates by mixing substrates and filtering seawater with a 0.28 cm sieve. The number of individual shrimp larvae released into net enclosures in each of the four treatments were: A) 2 400, B) 1 800, C) 1 200, and O) 0. The treatments were designed to represent the release of 1 billion, 750 million, 500 million, and no shrimp larvae (none-releasing) in the coastal waters of Laizhou Bay, respectively. The released shrimp larvae had an average body length of (1.63±0.18) cm and an average body width of (0.38±0.12) cm. At the end of the experimental period in September, shrimp and fishes were recaptured and their Levin's niche breadth and overlap indices were examined in each enclosure. Results indicated that within the enclosures of the four treatments, the recapture rates of shrimp ranged from 8.16% to 12.69% and had an average value of 9.87%. The number of recaptured shrimp increased with the number released, and had the highest value in enclosure A. However, the total biomass, average individual mass, and recapture rate of shrimp did not show a similar pattern among enclosures. The recapture rate of shrimp was significantly different among the treatments and had the highest value in enclosure C. The fish species composition was similar across all four treatment enclosures and included six species with three different feeding habits: Omnivores (Konosirus punctatus and Liza haematocheila), zooplanktivores (Thryssa mystax and Sardinella zunasi), and fish/shrimp predators (carnivores) (Acanthogobius sp. and Sparus microcephalus czerskii). Of the fish species, Acanthogobius sp. dominated in all enclosures, while S. m. czerskii occurred in only a few. There was no significant difference in the number and biomass of total fishes and carnivorous fishes among enclosures. There were more omnivorous fishes in the released enclosures A–C, while the number of zooplanktivorous fishes decreased when shrimp were released and had the highest number and biomass in the non-released enclosure O. Moreover, fishes with different feeding habits had variable niche breadths among the four treatment enclosures. Most fish species had a wider niche breadth in enclosures with released shrimp (enclosure A–C) than in enclosure O. Both the fish´s niche overlap indices and the species pairs with high niche overlap (> 0.75) decreased in the order non-released enclosure O > released enclosure B > enclosure C > enclosure A. The carnivorous fish Acanthogobius sp. had more pairs with niche overlap indices (> 0.75) in the non-released enclosure O than in the other three treatments. A similarity analysis and multidimensional plot indicated that enclosures A and O could be differentiated by the relatively long similarity distance and little overlap area. The results of the experiment suggest that the shrimp recapture efficiency did not increase when shrimp were released. In the waters of the study area, released shrimp could have a positive effect on the total output of both shrimp and fish, especially for omnivorous and carnivorous fishes, as the shrimp could share predation pressure and provide food for them. In addition, the shrimp release may affect the relative composition and niche characteristics of fish by increasing their niche breadth and reducing the overlap between fishes with different feeding habits, and the impacts may be more detectable as the shrimp number increases.

The microphysical characteristics is important for the formation mechanism of rainstorm which is the result of multi-scale conditions and the interactions of macro and micro physical processes.From 15:25 （Beijing Time， the same as after） to 17:27 on July 20， 2021， a strong mesoscale convective system affected Zhengzhou， and the accumulated precipitation was 312.1 mm， which was referred to as extreme rainstorm.Excluding the period of extremc rainstorm， from 08:00 to 20:00 on the July 20， the accumulated precipitation was 183.4 mm， which is referred to as rainstorm.Based on the observations data of disdrometer at Zhengzhou station， the characteristics of raindrop size distributions（DSDs） and integral parameters of extreme rainstorm and rainstorm are analyzed.The results showed that： （1）In rainstorm， the average DSDs increased with the increase of rain rate.The concentrations of diameter less than 1 mm increased less， and concentrations of large diameter which is greater than 2 mm increased faster.In extreme rainstorm， the average DSDs increased with the increase of rain rate， and the concentrations of each diameter increased significantly.Meanwhile， the differences between the concentrations of average DSDs at different rain rate were complex.Somewhile there were distinct differences in the concentrations of small raindrops， and there were also great differences in the concentrations of large raindrops.The differences of average DSDs of different rain rate categories lead to different parameters variation with the increase of rain rate.For rainstorm， the Dm increased with the increase of rain rate， while lgNw increased slightly， indicating that the main source for the increase of rainstorm intensity was the increase of particle diameter， and the secondary factor was increase of particle concentrations.For extreme rainstorm， when the rain rate was between 50 and 100 mm·h-1， Dm（lgNw） increased （decreased） with the increase of rain rate， while the rain rate was greater than 100 mm·h-1， Dm and lgNw increased slightly with the increase of rain rate， suggesting that the formation mechanisms of DSD in different rain rate categories of extreme rainstorm may be different.（2）The distribution of lgNw-Dm showed that the DSDs of rainstorm were mainly continental-like， and its formation mechanism was mainly warm-ice mixture process and a small amount of ice-based process.The scatter plot of lgNw-Dm ofextreme rainstorm with rain rate less than 100 mm·h-1 mainly clustered on the upper and right side of the continental-like area， and the formation mechanism of extreme rainstorm was mainly warm-ice mixture process and ice-based process； the scatter plot of lgNw-Dm of extreme rainstorm with rain rategreater than 100 mm·h-1were mainly distributed on the upperside of the continental -like area， and the formation mechanism was mainly warm-ice mixture process.（3）There were a small proportion（about 2.8%）of the equilibrium raindrop size distribution（EDSD） and a large proportion （about 60.5%）of transition DSDs in rainstorm.There was no EDSD in the extreme rainstorm， while the transition DSDs had a very high proportion （about 83.9%）， indicating that the breakup process played a much more role in the extreme rainstorm.

The traditional analytical method greatly underestimates the throughput capability of the system in low beam density scenario, and cannot reveal the capacity saturation phenomenon in high beam density scenario.To overcome the preceding problems, a new system simulation method was proposed to accurately evaluated the capacity density indicator of satellite constellation network and integrated satellite and terrestrial network, Based on this method, first, the capacity density of different longitude and latitude regions of the earth was evaluated.It could be observed that the capacity density of the same region varies greatly with the movement of the satellite, and the maximum capacity density was twice the minimum.Then, areas with higher visibility usually had higher capacity density.In high-frequency scenarios, the impact of atmospheric attenuation on capacity density could not be ignored.Finally, for the integrated satellite and terrestrial network, the evaluation results showed that the capacity density of cellular coverage and satellite coverage could differ by four orders of magnitude.In order to improved the capacity density of satellite constellation network, two technical paths were attempted: increasing the maximum number of illuminated beams and increasing the satellite scale.The results showed that the performance was better when the constellation scale was increased when the total beams of the constellation were the same.However, the two ways to increase the total number of beams in a constellation had an upper bound on capacity, and the marginal effect decreased significantly.Finally, a scheme to increase the gain of satellite antenna was proposed.The simulation results showed that the proposed scheme could significantly increase the capacity density of constellation.

Biodiversity loss is one of the major crises facing humanity today, and with none of the biodiversity targets represented by the Aichi Biodiversity Targets being met, there is an urgent need to promote transformative change to halt and reverse the trend of biodiversity loss. Nature-based solutions (NbS) have emerged as an important way to address the global crisis due to its inherent principles involving holistic and systemicness, diversity, stability, sustainability, trade-offs, and compatibility. The relationship between biodiversity and NbS is analyzed from a mechanistic and functional perspective, and the pathway of NbS as a proxy for biodiversity conservation is revealed by restoring of ecosystem complexity and trophic levels to put nature on the path. We here propose the dual intensions of promoting NbS for biodiversity conservation, as (1) the goal aimed at enhancing diversity, stability, and sustainability of ecosystem, and (2) the tool involves use natural processes. Based on the above understanding of the link between NbS and biodiversity, this paper further compares the conceptual connotation of NbS with the consistency of biodiversity conservation, as well as the NbS methods for biodiversity conservation including natural, agricultural and urban area. Practical cases of NbS for biodiversity conservation or synergy of NbS for biodiversity are summarized in align with differentiated typical ecosystems. The multiple benefits of NbS for biodiversity conservation, climate change and sustainable development are discussed. The vision of integrating NbS into strategic planning for biodiversity conservation is presented to provide a reference for promoting the implementation of Kunming-Montreal Global Biodiversity Framework and the mainstreaming of NbS in biodiversity conservation.

Haloxyfop-R-methyl (HPME) is a selective herbicide for gramineous plants and has a removal effect on the coastal invasive organism Spartina alterniflora. In order to assess the risks of HPME on marine organisms in the governance process of Spartina alterniflora, this paper used the static-test method to evaluate the acute toxicity of HPME on four marine organisms. The results showed that four test organisms all showed muscle relaxation, decreased exercise capacity, and slow response under HPME exposure. As the test time prolonged, the mortality rate gradually increased, indicating that HPME had neurotoxicity and cumulative toxic effect on marine organisms. The 96 h median lethal concentration (LC50) of HPME for Mactra veneriformis、Apostichopus japonicus larvae、Cynoglossus semilaevis fry and Assiminea. lutea were were 0.888 mg/L, 1.382 mg/L、0.656 mg/L and 8.674 mg/L, respectively. The safe concentrations (SC) were 0.088 8 mg/L, 0.138 2 mg/L, 0.065 6 mg/L and 0.867 4 mg/L. According to the environmental safety assessment test guidelines for chemical pesticides, HPME was highly toxic to Cynoglossus semilaevis fry and Mactra veneriformis, and was moderately toxic to Apostichopus japonicus larvae and Assiminea. lutea. The results provided a reference for HPME in the elimination of Spartina alterniflora.

Due to the complex environment and ground stress at depth, and the various cross-sectional shapes and sizes, the damage types of deep roadways are diversified. The maximum ground stress, maximum compressive strength, and the corresponding support methods are compared by systematically analyzing the influence of high stress and dynamic pressure on the deep weak surrounding rock of roadways. And the stress intensity ratio is proposed to evaluate the support difficulty of surrounding rock of roadways. Then, the concept of active-passive full space collaborative control is proposed, and the core of the concept is to control the deformation of the roadway through active support methods such as destressing, grouting and bolt-cable to bring the self-supporting capacity of the surrounding rock of roadway into play, forming an active support body, and restoring its partial bearing capacity. Using passive support methods such as concrete-filled steel tube sets and U-shaped steel sets with high support resistance to form a passive support ring to assist or mobilize the bearing capacity of the rock surrounding roadways. Additionally, the mechanical mechanism of the collaborative support for concrete-filled steel tube sets and bolt-cable were analyzed, and the active-passive full space collaborative control technology and construction technique were developed and applied in the field. The study shows that the bolt-cable can reduce the bending moment and shear force of the concrete-filled steel tube sets, while reducing the axial force of the support and protecting the steel tube and the core concrete with poor tensile properties. The active-passive full space cooperative control technology has been successfully applied in deep roadway subjected to dynamic pressure and weak rock roadway in Jincheng Hudi Coal Mine and Yangquan Xinyuan Coal Mine, which has further developed the theory and technology of equal-strength support in deep roadway.

A method was established to determine 22 free amino acids in food for special medical purposes by ultra-performance liquid chromatography. After extraction with sulfosalicylic acid and derivation with 2,4-dinitrofluorobenzene (DNFB), the samples were eluted with acetonitrile water-ammonium formate as mobile phase. Amino acids were separated by HSS T3 column and detected with diode-array detector by external standard method. Results showed that, the 22 amino acids were linear in the range of 2~100 µg/mL with correlation coefficients higher than 0.99. The limits of detection (S/N≥3) were 10 mg/100 g, and the limits of quantification (S/N≥10) were 25 mg/100 g. The recoveries were in the range of 90.1% and 109.1% with relative standard deviation (RSD) from 0.8% to 6.9%. This method was simple, efficient, accurate and reproducible. It was suitable for determination of 22 free amino acids in food for special medical purposes, which could provide technical support to ensure the quality and safety.

Objective To explore the influencing factors of herpes zoster neuralgia in order to provide reference for the diagnosis and the treatment of this disease. Methods We retrospectively analyzed 89 cases of craniofacial herpes zoster and 168 cases of non-craniofacial herpes zoster hospitalized in the First Affiliated Hospital of Wannan Medical College from January, 2019 to December, 2019. The demographic and clinical characteristics were compared between these two groups. Pearson analysis was used to determine the correlation between NLR and pain score and severity score of the skin lesions. Logistic regression was used to analyze the risk factors for herpes zoster neuralgia. Results There were no significant differences in age, gender, pain score and severity of skin lesions between the two groups when admitted to hospital. Patients with craniofacial herpes zoster had a higher rate of pustules, blood blister and necrosis than that with non-craniofacial herpes zoster (25.84% vs. 15.48%, χ2=4.05, P=0.044). Moreover, the NLR were higher in patients with craniofacial herpes zoster than that with non-craniofacial herpes zoster (4.11±1.62 vs. 2.35±1.51, t=6.27, P

Eight samples of No.11 coal in Sangshuping Mine were used for organic geochemical study, Gas chromatography-mass spectrometry (GC-MS) and X-ray fluorescence spectrometry (XRF) were combined with the test results of proximate analysis, sulfur forms and random vitrinite reflectance, the organic matter sources and coal-forming environment of No.11 coal from the Sangshuping mine, Shaanxi Province were comprehensively analyzed. The results indicate that the total sulfur content of the coal sample is 3.29%, and the mean vitrinite oil-leaching reflectance is 2.01%, which is high-sulfur lean coal. The phase parameters of major elements indicate that the coal samples are mainly formed in reductive sedimentary environment. There are two types of carbon number distribution of n-alkanes in saturated hydrocarbon: the front peak type main carbon peak is C16, and the back peak type is main carbon C26; Combined with the distribution characteristics of ∑C22−/∑C23+、(C21+C22)/(C28+C29)、Pr/nC17、Ph/nC18 indicated that the parent material of organic matter come from aquatic organisms and higher plants. The OEP value was between 0.49 to 1.05,with an average value of 0.84, indicating that No.11 coal of Sangshuping has undergone different degrees of biodegradation. In the analysis of saturated hydrocarbon steroidal terpanes, the ratio of w(Ts)/w(Tm) is between 0.83-1.21 and w(Ts)/[w(Ts)+w(Tm)] is between 0.45-0.55, indicating that the thermal evolution degree of coal sample is high. In the analysis of aromatic compounds, the methyl rearrangement of trimethylnaphthalene and the distribution characteristics of methyl phenanthrene index are correlated with the high thermal evolution degree of coal samples. The aromatic hydrocarbons were dominated by naphthalene, phenanthrene and biphenyl series, and the sulfur-containing compounds in the trifluorene series (oxygen-fluorene, sulfur-fluorene, fluorene) are obviously higher than the oxygen-containing compounds, which also indicates the coal-forming environment under higher salinity partial reduction conditions.

Based on the previous study on the long-term rise of water level in Bengbu monitoring center well, we analyze 59 short-time rises of the water level in Bengbu monitoring center well from 2017 to 2020. By selecting rainfall parameters in different periods andestablishing multiple regression equations, the results show that there is a certain relationship between 59 short-term rise of water level and some rainfall parameters. According to the analysis results of earthquake cases above ML2.0 and 13 non rainfall events around Bengbu, the surrounding area of Bengbu is mainly affected by ML2.0—3.0 earthquakes, with slightly weaker crustal stress release and minimal impact on underground fluids in Bengbu. Earthquakes above ML3.0 mainly occurred in the west of Anhui Province and near the Tanlu fault zone, with strong seismic activity. The observation data of underground fluid in Bengbu changed greatly and lasted longer. It is concluded that the short-time rise of water level is related to the change of crustal stress in Bengbu area while excluding the influence of rainfall. It can be seen that Bengbu monitoring center well has a certain prediction efficiency, which can reflect the changes of seismic stress field around Bengbu, and is of great significance for the analysis and prediction of earthquake precursor observation data.

Underground coal gasification (UCG) is the inevitable choice for China’s energy development and driven by the strategy of the development of efficient coal energy structure. The industrialization process needs to be promoted by all parties in coordination, and the making of industrial policy is the first to bear the brunt. Based on the background and extensive investigation on relevant situations at home and abroad, the difficulties faced by the making of industrial policies for UCG are analyzed and demonstrated, and the countermeasures and suggestions to solve the difficulties are put forward from four aspects, including the strategic value of UCG industrialization, market access and legal status of UCG projects in relevant countries, method of filing and approval of UCG projects in China, and the thinking on the making of UCG industrial policies. It is shown that the UCG project involves coal, oil and natural gas in the management of mineral resources. From the perspective of environmental protection management, it involves groundwater, soil and surface ecology, atmosphere and many other aspects. The management responsibility belongs to multiple government departments, and the application and approval process is very complex. Although relevant countries have made many attempts in the making of UCG industrial policies, there is no current and sustainable policy for improving UCG industry, which has become a “short board” for the promotion of UCG industrialization. Foreign experts have suggested to their own governments to launch the UCG technology as soon as possible through the policy and regulatory framework, and to eliminate social concerns about the environmental safety of UCG. For a long time, China has adopted the “one case, one discussion” method for the filing and approval of UCG projects. It is difficult for some UCG projects to be approved, which has greatly restricted the industrialization process of UCG. Based on the above difficulties, it is suggested that the government should formulate and issue an operable UCG industrial policy system, focusing on five directions: establishing a UCG project market access and approval system, clarifying the use of mineral resources and fiscal and tax preferential policies for UCG projects, bringing UCG scientific and technological innovation into the national major science and technology plan, building a UCG scientific and technological innovation platform system, and creating a high-quality professional talent training base of UCG. The purpose is to provide legal guarantee for promoting the industrialization of UCG in China.

The landslides induced by typhoons and rainstorms in Southern China are often shallow, fluidized and clustered. A large number of investigations have shown that vegetation infiltration has a significant impact on the formation of granite residual soil landslides. However, most of the current studies have focused on the effect of vegetation roots on soil infiltration. The influence mechanism of vegetation infiltration enhancement effect on shallow landslides has not been revealed. Therefore, the mass landslide disaster on September 9, 2019 in Longchuan County in Guangdong is taken as an example, and a large number of landslide site investigations are made to identify the geological environment conditions and vegetation development in the landslide area and analyze the infiltration effect of vegetation on shallow landslides. The “double-ring method” is used to measure infiltration rate of different vegetation types, and to analyze the infiltration process and infiltration law of different vegetation types. A typical landslide profile is selected to establish a geological model, and the Geo-Studio software is used to simulate the seepage law of shallow landslide and the stress-strain characteristics of the soil under heavy rainfall conditions (250 mm/d). Finally, combined with the simulation results and field investigations, the infiltration effects of vegetation and their response mechanisms to shallow landslides under heavy rainfall are analyzed. The results show that vegetation can effectively enhance the permeability of soil, and the order of permeability is coniferous forest land, shrub forest land and bare land. Under the influence of vegetation infiltration effect, rainwater infiltration to the bottom of the root-soil composite layer will cause water stagnation, the shallow soil tends to be saturated rapidly, the pore water pressure and seepage force in the soil increase instantaneously, the soil is saturated with water, the residual soil softens, and the weight of the slope increases, which eventually leads to the overall instability of the slope. The research results explain the formation mechanism of granite residual soil landslide in high vegetation covered area under heavy rainfall in Southern China, and provide scientific basis for early warning and prediction of such disasters, which are of great significance.

[Objective] The factors influencing landslide potential of loess terraces and the associated landslide formation mechanisms were studied in order to provide a scientific basis for the prevention and control of loess terrace landslides. [Methods] With data from the Google Earth Engine cloud computing platform for Pengyang County, Ningxia Hui Autonomous Region, we used the random forest algorithm to extract terrace distribution information in the study area. Based on the overlay analysis method, the high and extremely high susceptibility zones of potential loess terrace landslides in the study area were determined. Eight influencing factors were selected, and the certainty factor method was used for analysis. [Results] ① The terrace area in the study area accounted for 47.28% of the total area of the county. There were 86 potentially unstable slopes, and there were no deforming areas within the influence range of terraces. ② The high and extremely high susceptibility zones for potential landslides of loess terraces accounted for 46.68% of the total area of high and extremely high susceptibility zones in the study area (27.64% of the total area of terraces in the study area). ③ Rainfall, stratum lithology, gully density, and slope direction had strong controlling effects on the spatial distribution of potential landslides of loess terraces in the study area. [Conclusion] The main controlling factors for potential landslides of loess terraces in the study area were rainfall and stratum lithology, especially in the area where the annual rainfall was more than 450 mm and there were Quaternary stone loess with paleosol strata.

In recent years, fishery species have decreased in size and quality in the Yellow River estuary seas due to the effects of climate change and human activities, such as water and sediment regulation of the Yellow River, overfishing, and sewage discharge, among others. At the same time, the fishery resource structure has changed greatly: Small-sized fish with low value, shrimps and crabs became the main catches. To conserve natural resources and maintain local fishery harvests, conservation efforts such as stock enhancement and fishing quotas have been employed. Research on the biological characteristics of important fish can provide a scientific basis for the rational utilization and stock enhancement of fishery resources in the future, and it can also offer support for making relevant fishery policies.Liza haematocheila is an economically important fishery species in the Yellow River estuary and mainly feeds on zooplankton, phytoplankton, and organic detritus, which limits eutrophication and promotes energy and carbon cycling at the ecosystem level. The species plays an important role in ecosystem function and the maintenance of biodiversity. This study investigated the biological characteristics of L. haematocheila to provide a scientific basis for its conservation and rational utilization in the Yellow River estuary. Furthermore, it can provide basic biological data for the study of ecological restoration in the Yellow River estuary.This study evaluated the distribution of body length and weight, the relationship between body length and weight, reproduction, growth, death, and development. All of the analyses were based on sampling data from set nets between April and November 2020.The body length range of L. haematocheila was 45~460 mm, the average body length was 149 mm, and the modal body length range was 55~185 mm. The body weight range was 2~1100 g, the average body weight was 83 g, and the modal body weight range was 2~80 g. Both the average body length and body weight were the highest in May and the lowest in September. Overall, small individuals were the most common, and individuals with a body length of less than 200 mm accounted for more than 78%. Analysis of variance showed significant monthly differences in both average body length and weight of L. haematocheila. The relationship between body length and body weight showed a strong correlation within and between months [W=3.17×10‒5L2.82, (R2=0.980 5, n=984)]. The growth of L. haematocheila was negatively allometric, with the growth of body length being faster than that of body weight.The body condition of L. haematocheila decreased with time, though it increased in July and fluctuated with a downward trend from July to November. The nadir body condition was observed in June (1.102±0.173) and the peak body condition was observed in July (1.535±0.467).The rate of gonadal development varied from month to month, and the proportion of individuals who did not reach gonadal maturity was large, with an undeveloped gonad proportion of more than 50% per month. There was a peak spawning period from April to May.The growth curve of L. haematocheila was fitted, and its growth parameters were estimated using the ELEFAN method. The total death coefficient of the population was estimated using a length-converted catch curve, the natural death coefficient was estimated using the empirical formula of Pauly, and the population development rate was calculated. The results indicated that the asymptotic length (L∞) of L. haematocheila was 608 mm, the growth rate (K) was 0.31 a−1, total death coefficient (Z) was 1.42 a−1, natural death coefficient (M) was 0.51 a−1, fishing death coefficient (F) was 0.91 a−1, and its population development rate (E) was 0.64. The L. haematocheila resource was overfished in the shallow coastal waters of the Yellow River estuary, and its open fishing length (L50) was only 57.4 mm in this production survey.Fixed-net harvesting led to overfishing in the Yellow River estuary from April to November 2020, with juvenile fish and supplementary stocks experiencing the greatest impact. We should reconsider the management strategies for L. haematocheila in the Yellow River estuary, and promote stock enhancement at the same time. Artificial propagation technology for L. haematocheila should be considered for supplementing L. haematocheila in the Yellow River estuary seas. Research on the release time, release of krill size, population characteristics, growth, and development should be addressed to provide an informed and scientific basis for stock enhancement.

The Yellow River estuary is one of the three largest estuaries along the coastal waters of China, along with the Yangtze and Pearl River estuaries. Its adjacent seawaters are rich in biological resources, with abundant fish habitat, spawning grounds, and migration channels in the Bohai Sea and the Yellow Sea. However, as the waters are too shallow for a survey ship, data was insufficient for research in the intertidal zone of the salt and freshwater interchange. Instead, by interviewing and analyzing the daily catches by the set net of the local fishermen, this study explored the fishery biodiversity in the intertidal zone of the Yellow River estuary from April to November 2020. Yellow River estuary is rich in fishery resources, especially small fishery organisms and fish recruitment stocks. There were monthly variations in the dominant species composition and biodiversity index. A total of 61 species were recorded, most of which were fish and crustaceans. The diversity, evenness, and species richness index increased in summer (July and August) and decreased in autumn (October and November). By cluster analysis of the species compositions, the surveyed months can be divided into two groups: May to September, and October to November. Lateolabrax maculatus and Liza haematocheila were the most common and dominant species in all surveyed months. The main contributors to the catch of each month were: snails from April to July, snails and fish in August, fish in September, and crabs from October to November. Catches by the set net were mainly composed of individuals with body mass < 2 g from April to September. From body mass-frequency distributions, fish with body mass < 10 g were the main contributors to total catches from April to September. The mean body mass of fish in all surveyed months was 13 g/ind.. The dominant fish species with body mass with < 20 g were: Gobioidei in April; L. maculatus in May; Konosirus punctatus in June; Pennahia argentata, Gobioidei, and L. haematocheila in June to August; and Sardinella zunasi, Thrissa kammalensis, T. mystax, Sillago sihama, Tylosurus melanotus, Gobioidei, and L. haematocheila in September. From the above results, the local set net fishery survey proved to be an effective method of collecting fishery data in the intertidal zone and can be incorporated in studies considering the distribution of fishery resources and breeding grounds in the seawaters adjacent to estuaries. In addition, this study provided clear evidence that set net fishing practices could severely impact the natural recruitment and stock enhancement of fish resources due to the low selectivity of nets and the overlap with larval fish migration channels. The number of larval fish captured by the set net fishery was, roughly estimated, several times higher than the local enhancement released. To minimize the effects of net mesh size, considering the spatial-temporal distributions of fish larvae, set net fishing practices should be concentrated to summer and early autumn, though further research is required to comprehensively account for both the protection of fishery resources and livelihoods.

Two kinds of composite mineral admixtures were prepared by grinding iron tailings powder and silicon powder in the ratios of 3∶2 and 4∶1, respectively to substitute cement for the preparation of mortar and concrete samples. The basic properties of iron tailings-silica fume composite mineral admixture mortar and concrete have been studied through microstructure analysis, strength and durability analysis. Results show that: as the content of the composite mineral admixture increases, the heat of hydration reaction, compressive strength, split tensile strength and freeze-thaw durability of the sample gradually decrease; and adding iron tailings powder can increase the pore structure of the hardened mortar test block, which reduces the compressive strength and freeze-thaw durability of the concrete. However, increasing the amount of silica fume can increase the strength of the hydration reaction of the sample, and increasing the silica fume can reduce the content of Ca(OH)2. The CSH gel produced by the hydration reaction of silica fume can also refine the pore structure, thereby improve the microscopic properties, compressive strength, split tensile strength and freeze-thaw durability of concrete; make up for the negative impact of iron tailings powder on concrete performance. On the whole, the compressive strength of modified concrete is more than 85% of that of ordinary concrete, which can meet engineering requirements.

The geomorphology of southern Ningxia is dominated by loess hills, with gullies and well-developed small landslides in the area, making surface deformation monitoring difficult. To explore the identification method of geological hazards in the loess hilly area, Jingyuan district in the city of Guyuan in Ningxia Huizu Zizhiqu is taken as the study area, and the SBAS-InSAR technology is applied to process a total of 11 periods of ascending L-band ALOS-2 data collected from July 2016 to May 2021 to obtain the deformation rate of the Jingyuan district. Combined with high-resolution optical images, a comprehensive analysis is carried out according to factors such as deformation rate, deformation scale, slope, and disaster-bearing body. A total of 27 suspected hidden dangers are identified. After field verification, 22 of them show obvious signs of deformation and have clear hazard-bearing bodies. The time-series deformation analysis of the typical hidden danger points shows that these areas have continuous and significant surface deformation during the monitoring period, and the maximum subsidence rate reaches 91.53 mm/a. The results show that the combined L-band SAR and high-definition optical image data and the application of the integrated remote sensing identification method are highly accurate and are of high applicability in the area. The next step is to collect L-band data on a combination of ascending and descending orbits and to conduct in-depth research on the basis of LiDAR data from drones in order to further improve the accuracy of geological hazard identification and to provide technical support for the precise prevention and control of geological hazards.

In order to improve the mechanical properties of the metal matrix composite, the copper-graphene composites were prepared by FSP (friction stir processing) method. The samples were analyzed through the metal microstructure observation test and mechanical test, the effects of agitation speed and the amount of graphite on the microstructure and tensile strength of the composites were investigated, and the strengthening mechanism of the composites was studied. The results show that the effect of graphene on copper matrix is mainly reflected in load transfer and hindering dislocation movement and grain boundary growth in copper matrix. With the introduction of graphene, the grain in the nugget area has been significantly refined. The reason for grain refinement is the mechanical stirring of the stirring head and the obstruction of graphene to grain growth during recrystallization. The tensile strength of the copper-graphene composites is 5% higher than that of the base metal, up to 27749 MPa. The copper-graphene composites with good properties and uniform distribution of graphene can be prepared by FSP method, which can effectively improve the mechanical properties of copper alloy and provide theoretical basis and technical reference for its wide application.

Multi-sensor multi-target tracking is a popular topic in the field of information fusion. It improves the accuracy and stability of target tracking by fusing multiple local sensor information. By the fusion system, the multi-sensor multi-target tracking is grouped into distributed fusion, centralized fusion, and hybrid fusion. Distributed fusion is widely applied in the military and civilian fields with the advantages of strong reliability, high stability, and low requirements on network communication bandwidth. Key techniques of distributed multi-sensor multi-target tracking include multi-target tracking, sensor registration, track-to-track association, and data fusion. This paper reviews the theoretical basis and applicable conditions of these key techniques, highlights the incomplete measurement spatial registration algorithm and track association algorithm, and provides the simulation results. Finally, the weaknesses of the key techniques of distributed multi-sensor multi-target tracking are summarized, and the future development trends of these key techniques are surveyed.

The occurrence of time delayed rockburst usually has strong randomness and will pose a great threat to construction safety. Excavation disturbance and blasting disturbance will have impact of varying degrees on the potential time delayed rockburst area. It is of great significance to carry out studies of the characteristics and mechanism of time delayed rockburst in a TBM tunnel under the blasting disturbance. Based on a TBM headrace tunnel, five time delayed rockburst occurred in K54+000—K54+700 section during demolition tunnel blasting excavation are studied by using theoretical analysis and comparative analysis method. The results show that (1) strong and medium rockburst areas are located near gentle dip faults. Short and small concealed joints and fine joints with filling are developed in surrounding rocks. The slight rockburst is far from the fault or near the normal fault. Except for the fine joints with filling, at least one steep structural plane with filling tendency and dipping in SW direction is developed. (2) The time delayed rockburst of the TBM tunnel has longer delay blasting time and longer lag working face distance, and the disturbance effect of blasting on the TBM tunnel is relatively small. (3) Blasting disturbance makes it easy for the surrounding rock instability in the potential time delayed rockburst area, which accelerates the process of time delayed rockburst. The research results can provide a useful reference for the early warning and prevention of time delayed rockburst in TBM tunnels.

Bamboo and wood products for food contact are widely used in our family and working life, such as disposable chopsticks and chopping boards. Due to the special texture of bamboo and wood, some fungicides could be used to ensure their effects of application and to extend the storage period. There is a growing concern of whether residual fungicides in treated bamboo and wood products will migrate into foods to be harmful to human body. Furthermore, the methods of detecting residual fungicides are also focused as research hotspots. Based on the domestic and foreign research progress of fungicides in bamboo and wood products, this paper reviews the classification, application, limit standards and detection methods of fungicides in bamboo and wood products, and summarizes the migration rules of fungicide in systems of food simulation, which provid references for the analysis of fungicides. Finally, the problems of existing detection and migration study about fungicides in bamboo and wood products for food contact are summarized, and the research prospects are discussed.

The Yellow River Basin has active geological structure, rapid geomorphic evolution and significant regional differentiation of climate, resulting in many types of major disasters in the basin, wide distribution and strong paroxysm. Taking the Loess Hilly Region in the south of Ningxia as the research area, this paper introduces the concept of loess potential landslide of terrace. By combining historical data collection, remote sensing image interpretation, field investigation and mathematical statistics, it analyzes the development characteristics and distribution rules of loess potential landslide of terrace, and analyzes its formation reasons. The results show that: （1）There are 26 loess potential landslide of terrace in the study area, which are mainly distributed in the Quaternary loess, with a larger number of medium and long slopes, mainly loess potential landslide of terrace of shallow and middle-level, and the scale is mainly small. （2）The loess potential landslide of terrace are mainly distributed in loess hilly areas and large undulating mountain areas, the elevation interval of 1 800~2 000 m, and the slope direction is southeast, South and southwest in space; It is mainly distributed in rainy season or seismicity period in time. （3）Topography, stratum lithologic, rainfall, surface water and human engineering activities are the main factors for the loess potential landslide of terrace. The research results have guiding and reference significance for the risk identification and risk management of loess potential landslide of terrace in the Loess Hilly Region in Southern Ningxia and the Yellow River Basin.

In order to address the problem that the dynamic decay of shear strength of expansive soil in the process of rainfall infiltration cannot be considered in the traditional slope stability analysis of expansive soil, indoor direct shear test was carried out to systematically study the influence of dry density and water content on the indicators of shear strength of expansive soil, viz., cohesion and internal friction angle. At the same time, the stability analysis of the expansive soil slope based on the strength reduction method was carried out with the shear strength testing results, and the change law of slope stability with the dynamic decay of shear strength was obtained. The results show that the increase of water content and the decrease of dry density will cause the decay of cohesion and internal friction angle of expansive soil, and the decay of cohesion is significant, while the decay of internal friction angle is less; the stability of expansive soil slope is mainly controlled by the water content of weathering layer, and with the increase of water content of expansive soil, the slope gradually evolves from stable state to unstable state, while the influence of dry density on the stability of expansive soil slope is relatively small.

The Weibei Oil Field of the Ordos Basin has reservoirs of ultra-low permeability with small pores and complex pore throat structures. Imbibition is obvious at the early stage of water injection, which improved the effect of oilfield development. However, the characteristics of imbibition and the extent of EOR by imbibition are not clear. By collecting core samples from the third member of the Triassic Yanchang Formation in the Weibei Oil Field, physical property test, cast thin section observation, scanning electron microscope test, high pressure mercury injection and various imbibition experiments were carried out to study the reservoir physical properties and pore throat structure characteristics of the study samples, and to make imbibition experiments under different media types and different oil saturation. Three types of pores were discovered in the study area, namely, dissolution pore, intergranular pore and intergranular pore. The pore throat structure corresponding to different pore types are largely different. Pore throat structures of the reservoirs dominated by dissolution pores and intergranular pores gradually deteriorates. The oil displacement efficiency of fractured reservoir is higher than that of matrix reservoir with the values of 34.8% and 23.2%, respectively. The imbibition experiment under residual oil saturation shows that imbibition can improve the displacement efficiency of reservoir, but the increase is limited (5.3%-6.7%). The main factors affecting oil displacement efficiency are physical property, pore throat structure, medium type and oil saturation. When the reservoir physical property is higher, the pore throat structure is better and the oil saturation is relatively lower, the reservoir imbibition is relatively weak and the imbibition displacement efficiency is relatively low.

Extreme heavy precipitation in the Yellow River basin mainly occurred between June and August in summer. It is of great significance for improving climate prediction and preventing and reducing disaster events to study the characteristics of synoptic conditions of extreme heavy precipitation in summer in this basin. Using the daily precipitation data in summer at the 247 ground-based meteorological stations in the Yellow River basin from 1961 to 2017, we first analyze the distribution characteristics of regional extreme heavy precipitation events in this basin. Second,according to the dominant circulation systems at 500 hPa,the typical circulation patterns affecting regional extreme heavy precipitation in summer in this basin are classified into the blocking type,the low-trough type,and the typhoon-peripheral type. The characteristics of extreme heavy precipitation,water vapor transport and evolution,and circulation under the blocking type and low-trough type of synoptic conditions before the events are analyzed. The results show that (1) the thresholds of extreme heavy precipitation in summer in the Yellow River basin gradually increase from the east to the west and from the north to the south during past 57 years. The frequency of extreme heavy precipitation in the upstream area is higher than that in other areas. (2) The distribution characteristics of zonal wind anomalies at 200 hPa are similar for the blocking-type and low-trough type synoptic conditions,whose anomalies show a "- + -" pattern in the range of 20°-55°N from the north to the south. Their circulation patterns at 500 hPa vary greatly,with the low-trough type dominated by the zonal circulation and the blocking type dominated by the meridional circulation in the mid- and high- latitudes of Eurasia. The former has many small troughs and ridges in the range of 30°-65°N,while the latter is controlled by positive geopotential height anomalies in the low latitudes. (3) The water vapor of blocking-type synoptic condition mainly comes from the Indian Ocean and the Pacific Ocean,while that of the low-trough type mainly comes from the Pacific Ocean and the South China Sea. (4) The blocking high that causes extreme heavy precipitation mainly develops locally,and the signal of its development can be captured 1-2 weeks before its occurrence. The trough that causes extreme heavy precipitation mainly moves,and its initial signal and strong signal appear about 7 d and 2-3 d before the occurrence of extreme heavy precipitation,respectively.

The research progress of isotopic fractionation in the process of shale gas/coalbed methane migration has been reviewed from three aspects: characteristics and influencing factors, mechanism and quantitative characterization model, and geological application. It is found that the isotopic fractionation during the complete production of shale gas/coalbed methane shows a four-stage characteristic of “stable-lighter-heavier-lighter again”, which is related to the complex gas migration modes in the pores of shale/coal. The gas migration mechanisms in shale/coal include seepage, diffusion, and adsorption/desorption. Among them, seepage driven by pressure difference does not induce isotopic fractionation, while diffusion and adsorption/desorption lead to significant isotope fractionation. The existing characterization models of isotopic fractionation include diffusion fractionation model, diffusion-adsorption/desorption coupled model, and multi-scale and multi-mechanism coupled model. Results of model calculations show that the isotopic fractionation during natural gas migration is mainly controlled by pore structure, adsorption capacity, and initial/boundary conditions of the reservoir rock. So far, the isotope fractionation model has been successfully used to evaluate critical parameters, such as gas-in-place content and ratio of adsorbed/free gas in shale/coal etc. Furthermore, it has shown promising application potential in production status identification and decline trend prediction of gas well. Future research should focus on: (1) the co-evolution of carbon and hydrogen isotopes of different components during natural gas migration, (2) the characterization of isotopic fractionation during the whole process of gas generation-expulsion-migration-accumulation-dispersion, and (3) quantitative characterization of isotopic fractionation during natural gas migration in complex pore-fracture systems and its application.

In order to avoid softening and improve the mechanical properties of the aluminum alloy welded joints,the butt test of 5A06 aluminum alloy was carried out with FSW,and the welded joints were processed into metallographic samples and tensile samples of a certain size under the conditions of a rotating speed of 1 200 r/min and a welding speed of 150 mm/min,the effect of deep cryogenic treatment (DCT) time on microstructure and mechanical properties of friction-stir-welded joints of 5A06 aluminum alloy was investigated.The experiments were carried out by microstructure observation test,micro-hardness test and tensile test to characterize and analyze the joint organization and mechanical properties.The experiment results show that DCT can refine the grain and promote the precipitation of the second phase,thus the mechanical properties of the joints are improved.The tensile strength and elongation of the joints can reach 385.3 MPa and 17.2% respectively,which are increased by 7.4% and 23.7%,respectively after 12 h DCT compared with the joints without DCT.Therefore,DCT can effectively improve the mechanical properties of aluminum alloy joints and provide theoretical and technical basis for its application.

Under the vision of carbon neutrality, the energy structure in China will change tremendously, and the tasks of the oil & gas storage and transportation discipline will also change inevitably. In the context of realizing the carbon peaking and carbon neutrality goals, the mid-term and long-term forecasts of the energy demand and carbon emissions were made, the new tasks of the oil & gas storage and transportation discipline were analyzed systematically, and the development directions of this discipline were pointed out, including the pipeline transportation of high pour-point and viscous crude oil, the optimized operation of natural gas pipeline network, the efficiency and net zero emission of oil & gas storage and transportation, the construction of smart energy system, and the storage and transportation of new media such as carbon dioxide and hydrogen. Meanwhile, the development requirements for integrating the oil & gas storage and transportation discipline into the modern energy systems were proposed, so that the oil and gas storage and transportation industry could play a greater role in guaranteeing the energy security and achieving the "dual carbon" goal in China.

【Objective】With the implementation of "plastic ban" in Hainan Province, the traditional plastic bandage of rubber tree bud grafting can no longer be used, and it is urgent to use degradable materials as bandage in the process of rubber tree bud grafting.【Method】With Badi degradable bandage grafted by different workers as budding bandage, the effects of traditional plastic bandage and Badi degradable bandage on the survival rate, sprouting rate and growth potential of mini-seedling buddings and young seedling buddings of rubber tree were compared.【Result】The survival rate of mini-seedling buddings with traditional bandage was 47.33%-70.70% and the sprouting rate was 90.00%-99.53%, while the survival rate of buddings with Badi degradable film was 35.32%-57.00% and the sprouting rate was 86.18%-92.56%, indicating that the survival rate and sprouting rate of buddings with the traditional bandage were significantly higher than those with Badi bandage. In the first leaf whorl, the leaf whorl distance with the traditional bandage (19.24 cm) was significantly higher than that with the Badi degradable film (18.06 cm), and there was no significant difference in other growth indexes. In the second leaf whorl, the stem diameter of traditional bandage (4.62 mm) was significantly higher than that of Badi degradable film (4.06 mm), while the whorl distance of Badi degradable film (11.27 cm) was significantly higher than that of traditional bandage (9.88 cm), but there was no significant difference in the growth indexes of other scions. Among the young seedling buddings, the survival rate of traditional bandage treatment was 92.70%-98.09% and the sprouting rate was 93.64%-99.75%, while the survival rate of Badi degradable film treatment was 73.33%-86.67% and the sprouting rate was 92.50%-96.85%, indicating that the budding survival rate of the traditional bandage treatment was significantly higher than Badi bandage treatment, and the sprouting rates were above 90%, there was no significant difference in the growth indexes of scions.【Conclusion】The budding survival rates of mini-seedlings and young seedlings were significantly reduced by the Badi degradable film, and the sprouting rate of mini-seedlings and the growth potential of scions were significantly affected, but the growth potential of young seedling budding was not significantly affected. The bud grafting skill of the graft worker was also one of the key factors affecting the budding survival rate. Therefore, Badi degradable film could not be widely used in the mini-seedling buddings, but could be properly used in the young seedling budding of rubber tree.

The external excitation caused by random wind load can greatly affect the fatigue life of the wind power transmission system. A four-component model considering the wake effect is used to simulate the random wind speed of a wind farm， and combined with the finite element method， the fatigue life of the wind power planetary gear train is obtained. On this basis， the influence of the depth， length and extension angle of the sun gear single-tooth and double-tooth root cracks on the fatigue strength of wind power planetary gear trains is studied based on the sub-model method. Finally， it is found that the influence degree of the crack size parameters on the fatigue life of the wind power planetary gear train is: crack depth> crack length> crack extension angle. The effect of double root cracks on fatigue life is much greater than that of single root cracks， the fatigue life of the first-engaged tooth in the double-root crack state is much shorter than that of the single-root crack state， and the fatigue life of the later-engaged tooth is slightly larger than that of a single-tooth root crack state. Related research provides a theoretical basis for optimizing the service performance of wind turbines.