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In order to establish the standard preparation methodology for bioactive polysaccharide of fucoidan, this study carried out the research of preparation method of fucoidan from Saccharina japonica. Three extraction methods, high temperature pressure extraction (HPE), acid extraction (AE), and microwave extraction at 400 W (M400 W), 500 W (M500 W), and 600 W (M600 W) were selected. Subsequently, two precipitation methods, calcium chloride precipitation (CP) and ethanol precipitation (GAP) were used to remove alginate followed by finally precipitation of fucoidan with high concentration ethanol. Fucoidan extracts prepared in totally ten different conditions were collected, of which the contents of total sugar, total phenols, protein, uronic acid, and sulfate groups were analyzed. Meanwhile their antioxidant activities including Fe3+ reduction ability, ABTS+ and DPPH free radical scavenging ability were determined. The correlation analysis was conducted based on the above determined results to discover the relationship between preparation methods and fucoidan qualities. Accordingly, the preparation methods for fucoidan of high yield, high purity, and excellent antioxidant activities were selected. Results showed that the yields of fucoidan by acid extraction with calcium precipitation (AE-CP) and microwave extraction with calcium precipitation (M400 W-CP, M500 W-CP, M600 W-CP) were 3.821%, 3.516%, 3.376%, and 2.998%, respectively. Meanwhile, the sulfate content was 17.734%, 23.872%, 23.376%, and 22.149%, respectively. Their protein and total phenol content were below 1%, the uronic acid content was below 10%, and the Trolox equivalent (ABTS+ radical scavenging ability) was 5.637, 5.336, 6.567, and 5.616 μg/mg, respectively. Thus, the above four preparation conditions were ideal for processing of fucoidan, among which the method of microwave extraction followed by calcium precipitation showed advantages of short processing time and low solvent consumption that met the requirement of the environmental-friendly processing. This study systematically investigated the effects of preparation methods on the yield and quality of fucoidan, which provided a practical preparation methodology for fucoidan from Saccharina japonica with high yield, purity and antioxidant activity.

In order to study the mechanical properties and strain field evolution of gas-bearing coal under cyclic loading, the mechanical properties of gas-bearing coal under cyclic loading and unloading conditions were tested with the Rock Mechanics Test (MTS816) system and the independently developed gas-bearing coal gas-solid coupling device. The strength and deformation characteristics of coal samples under cyclic loading and unloading were analyzed, and the strain field evolution of gas-bearing coal was investigated with digital image correlation (DIC) technology. The results indicated that: ① Under the action of cyclic loading and unloading, the loading and unloading curves did not coincide with each other, forming a hysteresis loops. With the increase in the number of cycles, the area of the hysteresis loops gradually increased, and gradually moved towards the direction of increasing strain. Coal samples with varying gas pressures exhibited significant brittle failure under cyclic loading. ② Under the action of cyclic loading and unloading, the peak strength of coal samples decreased, and the loading and unloading deformation modulus increased with the increasing gas pressure. The unloading deformation modulus was always greater than the loading deformation modulus. As the number of cycles increased, the difference in deformation modulus gradually decreased and eventually fell within the range of 0 to 0.1 GPa. ③ Under cyclic loading and unloading conditions, the trend between the irreversible strain of coal samples and the number of cycles was a three-stage pattern of “initial, stable and accelerated expansion”, and the overall curve progressed from an L-shape to a U-shape. The trend between the cumulative irreversible strain and the number of cycles was rapidly increasing, slowly increasing and rapidly increasing, and both irreversible strain and cumulative irreversible strain increased with increasing gas pressure. ④ Under low gas pressure, the strain concentration area of coal samples was mainly a single vertical strain concentration zone. As the gas pressure increased, the local strain concentration zone gradually transitioned from vertical single to disordered and complex. The higher the gas pressure, the more pronounced the strain field fluctuation and the intensity was concentrated in the central region. At high gas pressures, the greater the number of peak points, the greater the strain with increasing gas pressure.

Pulverized fuel ash (PFA) is a by-product from coal-fired power plants. The generation of PFA is huge and increases yearly. A large amount of untreated PFA is harmful to the environment, and it is also a waste of resources. Recycling PFA as construction materials would improve resource utilization efficiency, reduce environmental risks, conform to the demand for high-efficient and low-carbon utilization of solid waste and help to achieve the national strategy goals of carbon peak and carbon neutrality. The utilization efficiency of PFA as construction materials could be improved by optimizing production processes and developing new technologies, which would promote its large-scale and high-value utilization. In this paper, the general situation and physical and chemical properties of PFA are summarized. Various value-added utilization technologies of PFA as construction materials, including raw materials for cement production, supplementary cementitious materials, bricks and blocks, artificial aggregates, glass-ceramic materials, fire-resistant insulation materials, and new intelligent construction materials are comprehensively reviewed. This paper also introduces the research status of the utilization of PFA in construction materials, analyzes the applicability of different technologies, summarizes the latest technologies for preparing the PFA-based green construction materials and challenges faced in future research, provides detailed introductions to the mechanism of PFA application, and proposes thoughts on the problems existing in the utilization of PFA as construction materials. Finally, the further perspectives of the development of the PFA-derived low-carbon construction materials are highlighted. The study suggests that the “traditional large-scale consumption of PFA” and “high-value utilization of PFA” should be researched in parallel, and theoretical research and engineering practice should support each other, which would provide some scientific references for the sustainable management of PFA.

CO2 adsorption causes damage degradation to the coal body and thus reduces its stability, challenging the long-term safety of CO2 sequestration, and it is important to clarify the role of CO2 degradation and establish an ontological model. The damage mechanics theory and statistical theory were used to derive the calculation formula that can comprehensively reflect the total damage variables of the coal body under CO2 adsorption and load coupling, and focusing on the influence of the pressure-tight section, the fine statistical damage ontological equation of the coal body under the action of CO2 was established by segmentation, and the method of determining each parameter of the model was clarified. Finally, the parameters of the constitutive model were determined by CT scanning experiment system and MTS 816 experiment system, and the uniaxial compression experiments of coal body under different CO2 pressures were carried out by the self-developed gas-solid coupling experiment system to verify the rationality of the model. The results show that: ① The damage variables under adsorption and loading were defined based on the fracture rate obtained from CT scanning and by applying the Weibull distribution theory, respectively, and the total damage variable under the coupling of the two was further obtained by combining the damage theory, and a fine-scale statistical damage constitutive model was established; ② Three-dimensional reconstruction of the fracture based on CT scanning technology realistically reflects the fracture extension characteristics before and after CO2 interaction， the higher the CO2 pressure, the fuller the fracture expansion, the greater the three-dimensional fracture parameters and damage variables of the coal samples, and the more complex the spatial fracture network formed; ③ CO2 had a significant deterioration effect on the physical properties of the coal body, and the compressive strength and modulus of elasticity of the coal body were both reduced by 49.78% and 22.63%, respectively, with the increase of CO2 pressure, and the combined effect of dissolution, plasticization and air wedge effect of CO2 on the coal body led to the reduction of the mechanical parameters; ④ The theoretical curves of the fine statistical damage model of the coal body under the action of CO2 have a high degree of agreement with the uniaxial experimental curves, which indicates that the present structural model can better reflect the damage degradation effect of CO2 on the physical properties of the coal body, and embodies the reasonableness and applicability of the constitutive model and the method for determining the model parameters.

Alzheimer's disease (AD) is a progressive neurodegenerative disease with insidious onset, commonly seen in the elderly and with increasing incidence, for which there is still no effective treatment. Medicinal and edible homologous substances refer to substances that are both food and traditional Chinese medicine, and have received widespread attention due to their safety and good therapeutic and health effects. This paper describes the pathogenesis of AD, and summarizes the anti-AD mechanism of medicinal and edible homologous substances from the aspects of slowing down the deposition of β-amyloid, inhibiting the over-phosphorylation of Tau protein, improving the cholinergic system, antioxidant, anti-inflammatory, and protection of neurons and synapses, so as to provide references for the development and application of medicinal and edible homologous substances products.

The evolution of fractures is affected by internal and external environments such as the distribution characteristics of mineral particles and confining pressure conditions. In order to explore the macro-meso evolution characteristics and influencing factors of fractures in fractured coal under different confining pressures, based on the industrial CT scanning system and its equipped triaxial loading system, the triaxial static load test of fractured coal was carried out. The interaction mechanism of internal and external conditions of primary fractures, mineral particles and confining pressure is reasonably explained by multi-angle joint characterization. the results showed：① The confining pressure will shift the significant area of the initial damage of the coal body, so that it transits from the fracture tip to the upper and lower ends of the coal body with the increase of confining pressure, and it is easier to connect between micropores and large-sized fractures than between micropores and micropores, and new macroscopic cracks are generated. ② The increase of confining pressure will lead to the change of three-dimensional dynamic fractal dimension from slow increase, rapid increase and steady increase to the development stage of steady increase, rapid increase and slow increase, which can be used to characterize the time evolution law of fractures. ③ The fractured coal body exhibits longitudinal tensile failure under uniaxial or low confining pressure. The high confining pressure will change its failure mode and tend to shear failure, and enhance the strength of the coal body through two ways. ④ The deviation between the theoretical value and the experimental value of the cracking angle increases with the increase of confining pressure, which is consistent with the discrete numerical relationship caused by the distribution of mineral particles in coal. ⑤ According to the stress composition of the fracture and the distribution characteristics of mineral particles, the fracture propagation behavior is divided into three types: direct drive, bypassing mineral particles and staggering mineral particles. The above propagation behavior depends on the confining pressure to change the force component of the crack. The cracks under the action of relative pure tensile stress, tensile-shear composite stress and relative pure shear stress correspond to the above three propagation behaviors, that is, the influence form of crack propagation is mainly confining pressure, supplemented by the occurrence form of mineral particles.

In order to study the ultrasonic propagation law and damage characteristics of the soft coal body, coal briquette is selected to replace raw coal, three wave propagation paths were set, and MTS rock mechanics experiment machine and PCI-II acoustic emission instrument were used to carry out the multi-path wave synchronization monitoring test of the coal body under the condition of uniaxial compression, and the anisotropy index was introduced to analyze the wave velocity evolution law. Three transverse and longitudinal sections were selected, and CT scanning equipment was used to carry out damage characterization experiments, reconstruct the micro-structure of the coal body after failure, and compare and study the differences in the distribution of the transverse and longitudinal fissures of two-dimensional slices, and to explore the relationship between the wave velocity and the three-dimensional volume of the fissures. Results show that: ① The parallel and vertical loading directions and the average wave velocity of the coal body show the basic law of smoothness followed by decrease and then smoothness with the increase of axial strain.The wave velocity anisotropy index has a smooth, then increasing and then smooth trend with the increase of axial strain, and the wave velocity in the vertical loading direction is the first to decrease, and the decrement is the largest. ② Compared with the vertical plane, the fracture spectral peak ratio and fractal dimension of the transverse plane of the damaged coal body are larger, the fracture density is higher, and the fracture morphology is also more complicated. ③ With the increase of fissure volume, the average wave velocity of the damaged coal body decreases roughly linearly, and the expansion of internal fissures in the coal body under uniaxial loading is dominated by the parallel loading direction, and the vertical linear expansion of the fissures is the main cause of the variability of the wave velocity in all directions and the damage characteristics of the transverse and longitudinal sections. ④ Compared with the parallel loading direction, the damage variables obtained by using the wave velocity in the vertical loading direction are larger and the evaluation of the damage state of the coal body is more reliable. When sound waves are used in the field to evaluate the damage state of coal , it is beneficial to improve the reasonableness of the prediction of instability accidents by making the sound wave propagation path perpendicular to the direction of the coal body loaded (maximum principal stress).

For the purpose of exploring the polysaccharide content, relative molecular mass, monosaccharide composition, as well as antioxidant activity in Ziziphus jujuba flesh polysaccharide (ZJFP) at distinct growth stages. The content, relative molecular weight, monosaccharide composition and free radical scavenging ability of ZJFP in wild-type and plant-type at different growth stages were studied by phenol-sulfuric acid assay, high performance gel chromatography, high performance ion chromatography, and DPPH free radical scavenging experiment. Moreover, the results determined that the polysaccharide content of ZJFP in both wild and plant types demonstrated a trend of first decreasing and consequently rising. Furthermore, the relative molecular mass of the two types of ZJFP gradually decreased with the development of the Ziziphus jujuba. During the initial stage of fruit development, the ZJFP exhibited the highest content of rhamnose, reaching 46.14 mg/g, followed by galactose up to 33.10 mg/g. Whereas, in the later stage of fruit development, the highest monosaccharide content in the two types of ZJFP was arabinose up to 60.30 mg/g, preceded by galacturonic acid up to 45.02 mg/g. Additionally, the trend of DPPH free radical scavenging capacity of ZJFP of the two types was identical to the trend of polysaccharide content in Ziziphus jujuba flesh. Plant-type and wild-type Ziziphus jujuba illustrated the identical trend regarding polysaccharide content, the relative molecular weight of polysaccharides, monosaccharide composition, as well as free radical scavenging ability, and both were of the type of fruit that reduces sugar accumulation. The research serve as a valuable reference for the future development and utilization of Ziziphus jujuba flesh resources.

Petrochemical wastewater contains heavy metals and petroleum-based pollutants and is a major environmental and biological health hazard. Zebrafish are sensitive to water quality changes and can be used as biological indicators for water quality monitoring. The type, concentration, and toxicity of pollutants in the water can be inferred by observing zebrafish survival, behavior, activity, and other parameters. However, the traditional method of monitoring zebrafish toxicity-response behavior by manual observation and analysis is subjective, labor-intensive, and inefficient. Therefore, automating the monitoring and identification of zebrafish toxicity-response behavior using computer vision technology is an important and challenging research goal. The common methods of computer vision technology in zebrafish toxicity-response behavior monitoring and recognition can be divided into three steps: Foreground extraction, target tracking, and behavior analysis. However, there are problems such as sensitivity to light changes, inability to deal with occlusion and overlapping phenomena, and low efficiency. Therefore, the aim of this study was to improve efficiency and detection accuracy in complex situations such as fish shading for the automated and real-time identification of zebrafish toxicity-response behavior. In this study, four typical pollutants (zinc, chromium, lead, and phenol) in petrochemical tail water were selected to experimentally observe the swimming behavior of zebrafish at different concentrations and exposure times. A multi-target tracking technique based on YOLOv8+ Bytetrack was used to extract the characteristic values of zebrafish movements (average velocity, maximum velocity, minimum velocity, and average number of collisions). YOLOv8 is a deep learning-based end-to-end target detection algorithm that enables efficient and accurate target detection. Bytetrack is a multi-target tracking algorithm based on target detection that can achieve real-time target tracking coupled with the use of low-scoring frames in the tracking algorithm for secondary matching, which can effectively optimize the problem of switching IDs due to occlusion in the tracking process. The convolutional neural network Resnet was used to analyze the motion trajectory maps of zebrafish. The bounding box and confidence level output from the YOLOv8 model were inputted into the algorithm to obtain a unique ID and trajectory for each zebrafish. Finally, zebrafish features such as position, speed, number of wall touches, and trajectory were extracted based on the tracking results. The experimental results showed that the algorithm's tracking accuracy, missing rate, and detection time (per 300 frames) reached 90.26%, 16.33%, and 0.19 min, respectively, which represented a considerable improvement in detection time and accuracy over those of traditional target-detection methods. The tracking accuracy of manual labeling was up to 100%, and the monitoring time was 125.62 min, which was 661.16 times greater than that of the multi-target tracking method in this study. Moreover, the detection times of the threshold segmentation-based Kalman filter, SOTMOT-based multi-target tracking, and FairMOT-based multi-target tracking were 3.59, 0.41, and 0.37 min, respectively, representing 18.89-, 2.16-, and 1.95-fold increases over that of the proposed method, and the tracking accuracies were 67.09%, 88.52%, and 90.10%, which represented only 74.32%, 98.07%, and 99.82%, respectively, of the accuracy of this method. Moreover, the missing detection rates were 72.80%, 20.69%, and 26.45%, which were 4.46, 1.27, and 1.62 times greater than the missing detection rate of this method. This method outperforms other multi-target tracking methods (SOTMOT and Deepsort) regarding target-tracking accuracy and precision. Meanwhile, the proposed method can accurately identify the corresponding movement status and trajectory changes in zebrafish based on specific pollutants. An increase and then a decrease in velocity were observed in zebrafish exposed to zinc sulfate and lead acetate as compared to that of the control group. A significant difference (P < 0.05) exists between the effects of zinc sulfate and lead acetate on the increase in velocity of zebrafish at the beginning of the exposure. The velocity of zebrafish in the potassium dichromate-exposed group showed a fluctuating trend, with values slightly lower than those of the control group. In contrast, the proportion of abnormal trajectories was significantly higher (P < 0.05) than that in the other experimental groups. Under phenol exposure conditions, the velocity of zebrafish tended to fluctuate over a wide range, while the number of wall touches was significantly higher than that in the other experimental groups (P < 0.05). At the late stage of exposure, the velocity of zebrafish in zinc sulfate, lead acetate, and potassium dichromate exposure groups gradually stabilized. The velocity of zebrafish under zinc sulfate and lead acetate exposure conditions tended to decrease significantly. In the potassium dichromate group, the velocity of zebrafish under 1 and 2 TU phenol exposure increased sharply and then fluctuated within a certain range, and 4 TU phenol exposure resulted in partial mortality of zebrafish. In summary, the multi-target tracking method can quickly identify the type of pollutant to which zebrafish are exposed by setting thresholds for the speed, number of wall touches, and percentage of abnormal trajectories in zebrafish behavior. This method is simple, effective, performs accurate identification, and determines real-time responses, making it highly valuable for reference in fish toxicity-response behavior identification.

Aiming at the frost heave characteristics of long-distance and large-section underground freezing projects in cities, the double-line tunnel of Shanghai Metro Line 18 undercrossing an operation station was select as an example,a three-dimensional numerical model was established by using finite element software based on the thermal-mechanical coupling equation. Combined with the physical parameters obtained from laboratory tests, the evolution law of frost heave displacement field of the project was studied, and the influence of measures such as the staggered peak freezing and the adjustment of brine temperature on the frost heave displacement field was explored. Under the experimental conditions, the results show that: ① the deformation of the station floor caused by frost heave which mainly occurs in the active freezing period. When the double-line tunnel is frozen at the same time, the vertical displacement of the station floor at 45days of freezing reaches 77.72% of the displacement at 90 days of freezing. ② When the freezing time reaches 90 days, compared with simultaneous freezing, the displacement of the station floor reduced by 7.7% under the condtion of staggered peak freezing. The superposition effect of frost heave in the same time period is effectively avoided, and the frost heave effect is reduced to a certain extent. ③ When the freezing time reaches 90 days, compared with simultaneous freezing, the displacement of the station floor reduced by 34.2% under the condtion of adjusting the brine temperature, it shown that the expansion rate and frost heave effect of frozen soil are effectively controlled. In engineering practice, measures such as staggered freezing and adjusting brine temperature are used together to control frost heave, and the maximum vertical deformation of the station floor is 25.41 mm. The deformation law of the station floor obtained by numerical simulation is basically consistent with the measured data, which effectively guided the construction of the project.

The coal industry is the ballast stone and stabilizer that supports the rapid development of China’s economy and society and ensures national energy security. It also undertakes the mission of ensuring energy supply and supporting the stable development of new energy. At present, the high-quality development of China’s coal industry has achieved some staged results, with remarkable achievements in energy supply, the continuous optimization of industrial structure, the significant improvement of scientific and technological innovation capabilities, and the continuous advance of green development and clean and efficient utilization. However, the current development level of the coal industry is far from meeting the national needs of Chinese-style modernization. The sustainable development is restricted by multiple factors. The digital technology and coal development and utilization have not yet been deeply integrated. The intelligent construction is still in the demonstration and cultivation stage. The green development is unbalanced and contradictory and prominent. The transformation and upgrading of the coal industry still has a long way to go. In view of the current development status and challenges of the coal industry, this paper proposes a synergistic development mode of digitalization, intelligentization and greenization (three -izations), clarifies the core connotation of new-quality coal productivity, constructs the overall framework of the synergistic development of new-quality coal productivity, and expounds the technical path for the transformation of the innovative allocation of production factors by digitalization, the breakthrough of key technologies led by intelligentization, and the deep transformation of traditional industries by greenization, i.e., by these three factors to generate new-quality coal productivity. Six major technical systems are proposed: through the research and development of the technical system of efficient data collection and in-depth governance of the whole industry chain, the data barriers among coal production, transportation, storage, marketing and use of the whole process are removed. Through the research and development of the knowledge map and intelligent decision-making and control technological system of the coal industry, the correlation relationship and value of the upstream and downstream business scenarios of the coal industry are deeply explored, so as to lay the foundation for the independent decision-making and intelligent control of the whole process of coal production and utilization. Also, the research should be carried out in terms of the intelligent-green-efficient development technological system of coal resources, the technical system of collaborative guarantee of safety in the coal industry, the technical system of ecological intelligent monitoring-early warning-restoration in mining areas, and the technical system of flexible development and clean and low-carbon utilization of coal, so as to realize the synergistic development of the whole industrial chain and the whole process of coal development and utilization, cultivate and form a new-quality coal productivity, and bring some fundamental changes and improvements to the overall image of the coal industry.

The mining industry is a sector aimed at the safe, efficient, green development, and clean, efficient, low-carbon utilization of mineral resources, serving as a foundational industry for economic and social development. In order to make mining development more economical, consider a more comprehensive range of factors, and optimize the design and development processes, in the late 1950s, operations research and computer technology were introduced into mining engineering, giving rise to a new discipline known as mining systems engineering. In its early stages, mining systems engineering primarily focused on the optimization of mining production processes and the use of computers in mine design, excavation planning, information processing, and application software development, with a predominant emphasis on open-pit mining as the research object. In recent years, research in mining systems engineering has closely integrated with big data, artificial intelligence, network technology, and has achieved fruitful results in areas such as mining information network construction, logistics systems, intelligent mining, equipment management, and safety management. This paper provides a detailed exposition of the origin and development process of mining systems engineering, with a chronological narrative based on international conferences on the application of operations research and computers in mining (APCOM), particularly the fifteen national conferences on mining systems engineering that have taken place. It objectively summarizes the developmental process and evolution of research content in mining systems engineering. Using the CNKI database as the data foundation, current research employs cluster analysis to study the publication volume, research objects, and their changes in mining systems engineering over the past 20 years. The future development of mining systems engineering should focus on the integration of systems science thinking with modern mining technology, establishing scientific systems and their boundaries, such as scientific mining systems, mine lifecycle systems, intelligent mine systems, and other eight major systems. The development of mining systems engineering will increasingly emphasize innovation and application in aspects such as digitization, intelligence, sustainable development, informatization, and automation, while continually expanding its application areas to achieve optimized, efficient, green, and low-carbon mining development.

The Yellow River Basin is an energy basin that has the dual responsibility of ecological environment governance and economic and social development. The precise and intelligent recognition of the categories, numbers and characteristics of coal-related industrial sites is a key basic issue for energy resources-low carbon development-ecological protection in the basin. This study integrated the multi-source data and deep learning algorithms to precisely analyze the characteristics of coal-based sites in 13 large-scale coal-fired power bases in the Yellow River Basin from the basin-base-site scale, obtained the high-precision and high-quality background information of coal-power bases, and proposed a new method of real-time real-scene intelligent recognition of spatial characteristics of coal-related industries. In this study, ① Multi-source data such as Google image, GF-6 image, Sentinel-2 image, etc. were collected as coal-based site samples from 13 large-scale coal-fired power bases to build four datasets of coal mine sites (open-pit), coal mine sites (underground), coal-power sites, and coal chemical sites, covering 21 categories of samples. According to each type of sample, 6×10 samples were set for each hexagonal cell, totaling 1260 site samples. The confidence interval of the optimal sample number-highest recognition efficiency-optimal recognition model was 80%−86%. ② A coal-based site classification quantitative model (CSCQM) and a coal-based site range characteristic model (CSRCM) were established. The average accuracy of the models was 0.837. The background information of coal-related industrial sites in the Yellow River Basin were clarified, and a high-precision site intelligent recognition method based on Google image base map overlaying site intelligent recognition model calculation results was proposed. ③ The precise background data of the Shendong coal-power industrial agglomeration area in the basin were analyzed. Analyzed by remote sensing based ecological index (RSEI), the surface ecological quality of the 2 km core area of coal-based sites was significantly affected by coal mine and coal-power industries, while the 5 km buffer zone was not significantly affected, and the 8 km control zone was basically not affected by coal mine and coal power industries. Thus, the low-carbon pathways such as dynamic remediation and key management by region and stage were proposed. ④ The precise background data of the Ningdong coal-power-chemical industrial agglomeration area in the basin were analyzed. In 2022, the area of coal mine sites covered an area of 17.81 km2, accounting for 34.1% of the total area, the area of coal chemical sites covered an area of 22.3 km2, accounting for 42.6% of the total area, and the area of coal-power sites covered an area of 12.2 km2, accounting for 23.3% of the total area. The area ratio was coal chemical sites > coal mine sites > coal-power sites. Then, using the PSR (Pressure-State-Response) model, the comprehensive score of risk management was obtained as 53.93 points, which was 27.2% higher than that in 2003. A zoning management mode of ecological maintenance zone, production monitoring and early warning zone, damage repair and reconstruction zone, and other regulation zone were implemented. The study provided some technical methods and practical support for the potential pollution control, site management and regional ecological restoration of coal-related industrial sites.

In order to improve the wear resistance and service life of mining sprockets, 40CrNiMoA sprockets cast by centrifugal electroslag casting were selected as the base material to study the effects of heat treatment processes on microstructure and mechanical properties of the alloy. The effects of different heat treatment processes on the mechanical properties of the steel, such as microhardness, friction and wear, and tensile strength were investigated with the orthogonal experiment method.The test results were analyzed by range analysis and comprehensive weighted scoring calculation to obtain the optimal heat treatment process parameters. Finally, experimental verification was conducted. The results show that the optimal heat treatment process obtained by the orthogonal test method is quenching at 880 ℃ for 0 .5 hours and high-temperature tempering at 600 ℃ for 2 hours. The microstructure of the sample after heat treatment is mainly tempered sorbite, with a Vickers hardness of 364 HV, a tensile strength of 1 166 MPa, and a wear rate of 0 .427×10-4 mm3/（N·m）. The validation test results are similar to the orthogonal experimental analysis, and the sample performance after heat treatment can meet the usage requirements. Therefore, the research results can provide a theoretical basis for the heat treatment process of mining sprocket parts, and are of great significance for effectively solving the wear resistance and service life of sprockets.

ObjectiveThis paper puts forward the “virtual wall method” as a novel formation approach intended to address such problems as the high communication volume, slow formation speed and inconvenient expansion of large-scale ship formation. MethodThe proposed method uses local communication, sets virtual force according to the rules of nature to drive the ships to the target positions, and adjusts the formation to completion through the virtual wall. ResultsThe results show that the ship formations can be completed quickly according to the proximity principle using the proposed algorithm, and the communication volume is low without changing with the formation size. The effectiveness of this algorithm is verified by static, dynamic, rotation, scaling and obstacle avoidance simulations of ship formations. ConclusionThe virtual wall method features low communication volume, fast formation speed and convenient expansion, giving it significant advantages in the large-scale formation of ships.

This paper mainly discusses the development status, pain points and future trend of China’s coal mine robot industry. In the context of the “robot +” era, this paper expounds the development of China’s robot industry from the aspects of the number of robot enterprises, regional distribution, industrial park construction, advantage track, national policy, etc., and expounds the changes and challenges brought by the domestic Internet and manufacturing enterprises. This paper focuses on the analysis of coal mine robot technology and industry pain points, and extracts three major capabilities that coal mine robot should have to realize intelligence. Strengthening the construction of supply chain and standard system is proposed. The classification standard of coal mine robot L0-L5 is introduced in detail.

This is an essay in the field of ceramics and composites.With the increasing demand for crude oil processing technology, China′s platinum rhenium catalyst industry is also developing. Catalyst is the core material of petroleum smelting, and impregnation method is the most important preparation method of reforming catalyst. Catalytic reforming catalysts generally refer to trace rhenium catalysts. The main research direction in the future is to increase the rhenium content of the catalyst and reduce the amount of platinum in the catalyst. The characteristics of platinum-rhenium catalysts are good stability, slightly poor selectivity, long-term stable operation, and regeneration cycle that can reach 3~5 years, which have been widely used in large-scale production of semi-regenerative reforming processes. Since the late 20th century, China′s refining catalyst market has formed a′Sinopec and PetroChina′s catalyst companies, supplemented by private catalyst companies′ market structure, catalyst demand is stable at more than 10 tons per year.

Objective: To express the protein HmpA of Salmonella paratyphi A in prokaryotes, and perform bioinformatics analysis on it to provide a theoretical reference for studying the effect of this protein on the nitric oxide (NO) signaling pathway in the host. Methods: The hmpA gene was amplified by PCR and subcloned into the T-vector. Then the expression vector pNdeI-hmpA was constructed and transformed into BL21 (DE3). After induced by IPTG, the recombinant protein expression form was assessed by SDS-PAGE. HmpA was purified using Histrap preload column and identified by Western blot. Bioinformatics technology was used to analyze the characteristics of HmpA. Results: The prokaryotic expression vector pNdeI-hmpA was successfully constructed. HmpA coexisted in the inclusion body and soluble forms under low temperatures after being induced with IPTG. The purified HmpA protein could be detected by the anti-His antibody. Bioinformatics analysis suggested that HmpA was a hydrophilic protein with no transmembrane structural domain or signal peptide. The secondary structure of this protein was mainly composed of α-helix with irregular convolutions, and the tertiary structure model was similar to a ring. The protein structural domain analysis showed that HmpA contains one functional structural domain belonging to the PRK13289 superfamily. There were 32 phosphorylation sites in HmpA. Associated with multiple Salmonella proteases or transcription factors that degrade nitrates and killer NO. Conclusion: This study successfully obtained Salmonella paratyphi A HmpA protein by genetic engineering technology and predicted part of its biological characteristics by bioinformatics methods, which would provide theoretical support for the subsequent uncovering of the influence of HmpA of Salmonella paratyphi A on the nitric oxide signaling pathway in the host.

High quality marine natural resource management cannot be achieved without the support of data and information. Given the unique nature of marine data, the processing of marine environmental data often involves long time series or large-scale processing work. For data processing work mainly focused on intensive computing, universal cloud platforms have prominent issues of low efficiency. Based on a comprehensive analysis of the native resource scheduling algorithms on the Hadoop platform and the characteristics of intensive computing in ocean data processing, this paper innovatively proposes a genetic algorithm task scheduling strategy based on a competitive model. The use of chaotic algorithm mechanism as the basis for genetic algorithm population initialization ensures that the solution space obtained during each initialization can be uniformly distributed, effectively solving the problem of genetic algorithm solving speed being greatly affected by the initialization population and population evolution measurement. In addition, in order to speed up rate of convergence, competition mechanism is introduced and an adaptive evolution model based on population competition is proposed. Through the actual verification and comparison of the built models, it is proved that the improved algorithm is superior to the traditional genetic algorithm in rate of convergence and stability of the convergence results, and has greatly improved the ability and efficiency of improving the resource scheduling of the ocean cloud platform.

Mastering fracture and movement of far-field high-position hard-and-thick strata plays an important role in safety prevention and control of disasters including severe surface subsidence and strong mine seismic events. The fracture mechanical model of high-position hard-and-hick strata is established based on the panels 2201 and 2202 in Yingpanhao Coal Mine. The fracture and movement of the Cretaceous sandstone formation and its influencing factors are analyzed by using the theory of Vlasov thick plate, which is verified and analyzed by surface subsidence and microseismic events. The conclusions are as follows: ①In view of the occurrence characteristics of Cretaceous sandstone group that is far away from the coal seam, with large thickness and good integrity, a high-position hard-and-hick strata fracture mechanical model is established. And the critical mechanical conditions for the first fracture of high-position thick-and-hard rock stratum are calculated by Vlasov thick plate theory. ② With the increase of tensile strength, the fracture overhang length of hard-and-hick stratum slowly grow, linearly grow, and exponentially grow; As the thickness of the stratum increases, the fracture overhang length of the thick and hard rock stratum increases exponentially; With the increase of the overhang length along the dip (width of panel), the fracture overhang length of thick and hard rock stratum increases first and then decreases. ③ During the extraction of panel 2201 in Yingpanhao Coal Mine, the hard-and-hick stratum did not break; And when the panel 2202 advanced about 960 m, the vertical "O-X" fracture occured; When the panel continues to advance about 188 m, the hard-and-hick stratum breaks periodically. ④ The monitoring results of surface subsidence show that the surface subsidence value of panel 2201 is small as a whole, and there are many small energy micro-seismic events. The surface subsidence of panel 2202 has experienced slow subsidence, rapid subsidence and stable stages in turn, and the frequency of high-energy mine seismic event has increased significantly. The location of the high energy mine seismic events and the area of the maximum surface subsidence are highly coincident, both in the O-X break area; The surface subsidence velocity reached the maximum of the 9.87 mm/d at 960 m away from the setup room, inducing the “6·8” strong mine seismic event. The above phenomenons verified the correctness of the far-field thick and hard rock stratum fracturing behavior. The research results of this paper have guiding significance for the study on the fracture of thick and hard rock stratum and disaster pre-control under similar engineering geological conditions.

In this study, the inhibitory effect of rape bee pollen polyphenols on pancreatic lipase was measured by enzyme kinetics method, and the interaction between pancreatic lipase and rape bee pollen polyphenol extracts was analyzed by the ultravilolet, fluorescence spectra and synchronous fluorescence spectra. The results showed that rape bee pollen polyphenols had a certain inhibitory effect on the activity of pancreatic lipase, and the half maximal inhibitory concentration (IC50) was 1.670±0.045 mg/mL. The inhibitory type was a mixed inhibition of reversible inhibition. Fluorescence spectra showed that the maximal fluorescence intensity of pancreatic lipase gradually decreased with the increasing of rape bee pollen polyphenols concentration, and the maximal fluorescence peak had a redshift from 341 nm to 349 nm. Synchronous fluorescence spectra showed that the hydrophobicity inside the enzyme decreased and the stretch of the peptide chain increased when polyphenols bind to pancreatic lipase. The fluorescence quenching mechanism showed that the quenching constant decreased from 0.1000 to 0.0743 with increasing temperature, and the binding process was static quenching with about one binding site. In conclusion, the rape bee pollen polyphenols could inhibit the pancreatic lipase activity by changing the enzyme conformation, which provided a certain theoretical basis for the mechanism of bee pollen lipid reduction.

The heat generation mechanism, wear behavior and quantitative relationship between cutting load and coal rock characteristics of the interaction between the cutting tool of mining machinery and coal rock mass, are the keys in solving the wear failure short life of the cutter, and realizing the safe and efficient heading. By comprehensively analyzing the impact of temperature on tool life, wear, and cutting efficiency, the temperature and wear distribution law of disc cutter in cutting coal rock are explored, and the heat generation mechanism and wear characteristics of disc cutter in cutting coal rock are revealed. Under the cutting conditions of non-vibration and axial excited vibration, the heat flux calculation formulas of the cutter wedge surface and the blade are established by friction work. Based on the semi-infinite heat transfer model under the condition of instantaneous point heat source and heat compensation principle, the heat transfer models of wedge irregular surface heat source and blade line heat source of disc cutter are given, and the temperature mathematical model of any point is established. Also, the influence of relevant parameters on the temperature field of cutter was solved and analyzed. Using the finite element ABAQUS, and discrete element EDEM software, the study simulates the temperature field and wear characteristics of disc cutter in cutting coal rock at different feed speeds, and sets up an experimental system for vibration cutting coal rock with disc cutter. Furthermore, the study tests the temperature characteristics of coal rock broken by disc cutter, and comprehensively investigates the distribution law of temperature and wear behavior characteristics of disc cutter in theory, simulation, and experiment. The results show that the characteristics of temperature variation of disc cutter are mainly concentrated on the blade, which decreases gradually from the blade to the wedge surface. The temperature distribution along the circumference of disc cutter is like a parabola, and the temperature decreases gradually from the middle blade to both sides. Under different feed speeds, the steady-state average maximum temperatures obtained by theoretical calculation (cutting time tends to infinity) of non-vibration and axial excited vibration are 374.76 ℃ and 245.72 ℃ respectively. The average maximum temperatures obtained by simulation (cutting time is about 3 s) are 80.13 ℃ and 73.60 ℃ respectively, and the average maximum temperature without vibration is 8.87% higher than that with vibration. And the experimental results (cutting time is about 3 s) are 72.56 ℃ and 66.99 ℃, and the average maximum temperature without vibration is 8.45% higher than that with vibration, the average error between simulation and experiment is 11.69%. In the experimental process of disc cutter in cutting coal rock, the circumferential spin phenomenon of the cutter is conducive to its evenly wear, and vibration cutting is more obvious than non-vibration. The temperature dissipation of the disc cutter blade presents a nonlinear downward trend, which is rapidly transferred from the blade to the wedge surface, its structural form can avoid aggravating the local wear of the cutter due to the accumulation and concentration of temperature. The disc cutter wear is concentrated at the blade, the relative wear along the circumference is a parabola distribution, the relative wear of the middle blade is larger, and the relative wear of the two side blades is gradually reduced. And the ABAQUS simulation combined the cutter wear model estimates the characteristic law of relative blade wear, which are the same as that obtained by EDEM simulation. The relative wear amount of disc cutter circumference is consistent with the temperature characteristic law, the correlation coefficients are higher than 0.90, cutting temperature can characterize the cutter wear. The internal connection between the temperature distribution characteristics of disc cutter in cutting coal rock and its wear law is obtained by comprehensive theory, simulation, and experiment, the three temperature variation laws are consistent, which verifies the accuracy and effectiveness of the cutter heat transfer model.

Edwardsiella tarda is a major causative pathogen of bacterial ascites in Japanese flounder, leading to massive economic losses, and the discovery of molecular markers linked to disease resistance is an effective strategy in resistance breeding programs. The Rho GTPase family comprises small proteins with a molecular weight of 20~30 kDa. Rho GTPase family members are involved in diverse cellular processes, such as cytoskeleton, cell adhesion, vesicle transport, and proliferation. In addition, they play pivotal roles in infection by different pathogens. Rho-related GTP-binding protein Rho6 (Rnd1), a member of the Rho-GTPase family, participates in various biological functions, including neural junction formation, axonal extension, tumorigenesis, neuronal function, and apoptosis. Some members of the Rho family, such as Rac1 and Rac2, regulate immune response in grass carp, large yellow croaker, zebrafish, and half-smooth tongue sole. However, the function of Rnd1 in fish is poorly understood. Japanese flounder (Paralichthys olivaceus) is greatly affected by E. tarda infections during the breeding process. In previous studies, whole-genome sequencing and assembly of Japanese flounder were performed, and subsequently, various disease resistance genes were screened to support the improvement of Japanese flounder germplasm resources. To study the role of Pornd1 in resistance against E. tarda infection in Japanese flounder, Pornd1 was cloned and identified using PCR. The full-length Pornd1 cDNA was 699 bp, containing an open reading frame encoding a 232-amino acid protein. The predicted molecular weight of PoRnd1 was 26 kDa. Sequence and homology analyses showed that the Rnd1 protein harbors a Rho-GTP superfamily structural domain, which is highly conserved in various species. PoRnd1 shares the highest homology with Rnd1 from Hippoglossus hippoglossus (98.28%). On phylogenetic tree, PoRnd1 was clustered with Rnd1 from other fish species. The single-nucleotide polymorphism (SNP) locus associated with E. tarda resistance is located at 4 575 720 bp on chromosome 14 of Japanese flounder. The frequency of the T allele in disease-resistant families (freqT=0.92) was significantly higher than that in susceptible families (freqT=0.20). The SNP was located at the 2nd intron of Pornd1. Real-time quantitative PCR was employed to characterize the expression profiles of Pornd1 in the tissues of healthy and E. tarda-infected fish. Pornd1 expression was the highest in the heart, followed by the liver, kidney, head kidney, and spleen, but its expression was low in the skin, blood, gills, and muscle. In E. tarda-infected fish, the expression of Pornd1 mRNA decreased after 6 h, then gradually increased, and subsequently reached the highest level after 48 h in the liver, kidney, and spleen. Pornd1 expression in the kidney and spleen in the 48 h group was significantly higher than that in the 6 and 12 h groups. Furthermore, Pornd1 expression in the liver of resistant families was significantly higher than that in susceptible families. Based on its His tag, the PoRnd1 recombinant protein was purified using an Ni column and subjected to SDS-PAGE. The target band of PoRnd1 at 32 kDa was observed in the gel after Coomassie Blue staining. The PoRnd1 recombinant protein (0.5 mg/mL) was used to study antibacterial activity through the Oxford cup assay. PoRnd1 significantly inhibited the growth of Staphylococcus aureus, Escherichia coli, E. tarda, and Vibrio harveyi. In summary, Pornd1 may be closely linked to disease resistance in Japanese flounder and can thus serve as an effective gene marker for disease resistance breeding. Our findings provide a theoretical basis for further elucidating the molecular mechanisms of immunity in Japanese flounder.

【Objective】The effects of irrigation period and frequency on the yield and quality of linseed were clarified to provide reference for water-saving irvigation in linseed producing areas.【Method】The yields, qualities and lodging resistances of linseed under different irrigation treatments were evaluated in this study by setting irrigation treatments at 3 growth stages (fir-needle stage, initial flowering stage and filling stage) with different irrigation times (irrigating once in each period, irrigating twice in any 2 stages, and irrigating 3 times in all 3 stages).【Result】The results showed that irrigation had a positive effect on linseed growth in arid areas with annual rainfall of about 220 mm. Compared with the control without irrigation, each irrigation treatment increased the yield of linseed by 2.5%-75.1%. The average yield of irrigating once, twice and three times was 1 321.5 kg/hm2, 1 375.5 kg/hm2 and 1 870.5 kg/hm2, respectively, which was 23.7%, 28.8% and 75.1% higher than that of the control (1 068.0 kg/hm2), correspondingly. It was showed that the plants were more robust and with higher bending resistance in the treatment of fir-needle stage irrigation (including single and multiple irrigation) than in the treatment of no irrigation in the fir-needle stage. Compare to the control, the contents of crude fat and α-linolenic acid for irrigation treatments were lower, decreasing by 2.22%-6.96% and 0.21%-9.44%, respectively.【Conclusion】In this research, irrigation three times (irrigating once at fir-needle, initial flowering and filling stage, respectively) is an effective irrigation measure for linseed production in arid areas, and its net income is the highest, with an increase of 4 807.5 yuan/hm2 compared with no irrigation. However, the yield to input ratio of irrigating once (at the fir-needle stage) is the highest (4.06), and the yield efficiency is good, reaching 97% of the income of the treatment of irrigating three times, which can be used as an alternative water-saving irrigation scheme in this region.

[Objective] The tilt photogrammetry of single landslide was carried out by a flexible light rotary-wing UAV in order to explore a method that can meet the needs of geological disaster investigation and assessment in loess region under complex terrain conditions. [Methods] The study was conducted for the Zhaojiaan landslide in Yan’an City, Shaanxi Province. Multi-view, high-overlapping, and high-resolution landslide images were obtained by using UAV tilt photogrammetry technology to generate a digital elevation model (DEM), a digital orthophoto map (DOM), and a real-world 3D model. Spatial geometric information of the landslide body was then acquired, and the Zhaojiaan landslide risk was evaluated by combining the analytic hierarchy procedure (AHP) and the hazard calculation method. [Results] ① By interpreting the high-resolution DEM, DOM, and multi-level real-world 3D model, the fine topographic and micro-geomorphic features of the landslide were extracted, thereby improving the accuracy of geological hazard interpretation and effectively reducing the labor intensity, time cost, and operational risk of manual geological hazard investigation; ② The hazard value (R) of the Zhaojiaan landslide was 0.635, designating it as a high hazard slope. It is therefore necessary to strengthen professional monitoring work. [Conclusion] The method of landslide investigation and risk assessment based on UAV tilt photogrammetry technology is especially suitable for landslide investigations in loess areas with steep valley slopes, deep river valleys, and sparse vegetation. This technology appears to be a promising method for risk assessment of single landslide hazards in loess areas.

Interferon regulatory factor (irf7) is an immune regulatory factor that plays an important role in the antiviral process. To explore the role of irf7 in Oplegnathus punctatus (Temminck & Schlegel, 1844) under viral infection, we cloned the coding DNA sequence (CDS) region of irf7 through PCR and analyzed the expression patterns at both tissue and cell levels. The results showed that the CDS region of Opirf7 was 1 332 bp and encoded a peptide with 443 amino acids. The predicted molecular weight was 50.5 kDa and the theoretical isoelectric point was 5.546. Protein structure analysis showed that Opirf7 has three conserved domains: the DNA binding domain (DBD), IRF-associated domain (IAD), and serine-rich domain (SRD). Amino acid similarity analysis showed that OpIRF7 had the highest similarity to the IRF7 of Lates calcarifer, which was 82.92%. The similarity of Opirf7 with the IRF7 of Larimichthys crocea, Paralichthys olivaceus, and Cynoglossus semilaevis were 81.99%, 79.95%, and 73.74%, respectively. Phylogenetic analysis showed that Opirf7 and other fish irf7 genes were clustered into one branch, and irf7s from Gallus gallus, Mus musculus, Macaca mulatta, and Homo sapiens were clustered into another. Tissues from healthy O. punctatus were collected, including the liver, spleen, kidney, head kidney, intestine, gill, skin, muscle, brain, heart, and blood. After RNA extraction and cDNA synthesis, real-time PCR (qPCR) was performed to detect the expression level of Opirf7 using the comparative CT method (2−ΔΔCT method). The results of qPCR showed that Opirf7 was expressed in different tissues of healthy individuals and its expression was highest in the liver, followed by the skin and intestines. The lowest expression was observed in the head kidney. In this study, the expression profiles of Opirf7 before and after viral infection were determined at the tissue and cell levels. For the in vivo challenge study, fish were intraperitoneally injected with spotted knifejaw iridovirus, and the expression level of Opirf7 was tested in the spleen, kidney, and liver. Compared with the control group at 0 h, the expression level of Opirf7 was 15-fold in the spleen and 3-fold in the kidney 4 days after infection, and the expression peak was at 7 days after infection. However, the expression of Opirf7 was not significantly altered in the liver. A poly I: C-infected O. punctatus brain cell model was established, and the expression profiles of Opirf7 mRNA were detected before and after infection. The expression of Opirf7 mRNA in the low and medium concentration groups (50 μg/mL and 100 μg/mL, respectively) increased by 13 to 17 times, and the expression level of Opirf7 mRNA in the high concentration group (200 μg/mL) increased by approximately 8 times. It was speculated that the high concentration of 200 μg/mL caused some damage to the cells and that the expression level in the high concentration group was lower than that in the low and medium groups. In this study, the full-length open reading frame sequence of Opirf7 was cloned and characterized for the first time. The deduced amino acid sequence displayed a structure similar to those of other vertebrates. Further functional analysis showed that Opirf7 has a significant response to viral infection at both tissue and cell levels. This study demonstrated that the Opirf7 gene might play an important role in the antiviral response of O. punctatus and provide a potential molecular marker for antivirus breeding of O. punctatus.

Langshan Branch Fault is the dominant fault controlling Jartai Structural Belt in Hetao Basin and the hydrocarbon accumulation of many high-capacity oil-gas wells has close evolutional relationship with the formation of the fault. The geometric characteristics and motion characteristics of Langshan Branch Fault were analyzed based on 3D seismic data and well-drilling data. According to the changes in fault displacement, and occurrence of the fault, Langshan Branch Fault was divided into three sections: north section, middle section and south section. Based on reverse fault theory, the inversion types and stages of the fault were made clear. A model was established with the method of formation tendency. and the drilling well sound wave time-difference point-control correction method was adopted to calculate the original thickness of the stratum of the hanging wall and the footwall and recover the ancient fault displacement of the fault, 6 different calculation methods were summarized for three kinds of growth faults including the normal fault, the reverse fault and the negative inversion to quantify and calculate the activity rate of each fault section in different depositional stages. The quantitative evaluation of the activity characteristics of the faults at north section, middle section and south section was carried out. Based on the comparison of the balanced cross-sections and analysis of the activity rate, it was deemed that Langshan Branch Fault experienced four evolution stages. There were three "isolated" faults with different trends and strikes in the early stage of development. In the depositional stage of the Lisangou Formation in the Early Cretaceous, the sectionalized thrusting existed and the north section and the middle section of the fault were flexibly connected. In the depositional stage of Guyang Formation, all thrust faults in the sections were reversed into the normal faults. It was strongly extended from the Paleogene to the Neogene, and the northern section and the middle section of the fault were hard-connected as a whole fault. From Late Neogene to the Quaternary, the fault underwent the local strike-slip twist, and these three sections of the fault were formally linked into the present connected fault. The activity of this fault in different historical stages obviously controlled the development of the sedimentary system of both the hanging wall and the footwall, the formation and evolution of traps, and the migration and accumulation of oil and gas.

In this study, the frozen surimi was select as the main raw material, and the effects of starch types, and the additions of starch, salt, leavening agent and egg white powder on the gel strength, expansion ratio, texture properties, and sensory score of surimi billets expanded by microwave were investigated by using single factor experiments. The key factors that influence the quality of surimi billets were screened by the Plackett-Burman experiment, and the optimal formulation of the microwave expanded surimi billets was determined by Box-Behnken design and response surface methodology. The results showed that the optimal starch added in the microwave expanded surimi billet was glutinous rice starch. The amount of salt, glutinous rice starch and leavening agent were the three key factors that determined the quality of surimi billets. The optimal formula of microwave expanded surimi billet was obtained at the salt amount of 2.16% , the glutinous rice flour amount of 6.26%, the compound leavening agent amount of 0.49% and the egg white powder amount of 0.9%, based on the weight of surimi. Under this condition, the gel strength of microwave expanded surimi billet was 16729.33±270.72 g·mm, and the sensory score was 85.8±0.84, respectively, and there were no significant difference between the verification value and the predicted values (P>0.05). The study provided a reference to the development of new surimi products.

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.

Flow cytometry is a biological technique for counting and sorting out tiny particles suspended in fluid based on flow cytometer through the detection of scattering or coupled fluorescence signals to obtain a series of important biophysical and biochemical related characteristics of suspended particles (usually cells, bacteria and other tiny particles) in a quick, accurate, objective and high-throughput way, and to automatically analyze and sort out specific populations according to the pre-selected parameter range of cells, bacteria and other tiny particles. Flow cytometry is widely used in many scientific fields, especially biotechnology and medicine. Although the application of flow cytometry in agricultural research started relatively late, great progress has been made. With the continuous improvement of the performance of flow cytometer, the continuous development and improvement of labeling methods and detection technologies, the application prospect of flow cytometry will become wider, and it will also play an increasingly important role in the agricultural field. In this review, it introduces the working principle and functional classification of flow cytometer, discusses the application and research progress of flow cytometry in agricultural fields such as crop genome and protoplast analysis, stress resistance research, animal immunity and trace element analysis, sperm quality and sex control, toxin toxicity analysis, pathogenic bacteria and virus analysis, and then looks forward to the development prospect of this research field, providing a new direction for the potential application of flow cytometry in agricultural fields.

ObjectivesFlow separation increases the drag and noise of underwater vehicles, and influences the controllability of their control surfaces. Therefore, the influence of slip caused by superhydrophobic surfaces on drag reduction and flow separation is studied. MethodsA partial slip boundary condition is developed, and the flow around a circular cylinder and foil with a slip boundary at high Reynolds numbers are numerically simulated. ResultsThe results show that the when the slip length increases, the flow around the cylinder goes through three stages: the turbulent Kármán vortex street, laminar Kármán vortex street and non-separation Stokes flow. The drag coefficient increases first and then decreases, and the vortex shedding frequency increases. For flow around a foil, the separation position moves downstream until the separation region disappears when the slip length increases, and the drag coefficient decreases while the lift coefficient increases. ConclusionsThe results of this study show that for flow past bluff body at high Reynolds number, the slip boundary can control flow separation and reduce drag effectively, providing technical support for the application of superhydrophobic surfaces for the flow control of underwater vehicle appendages.

To solve the problem of low polishing efficiency of silicon carbide crystal, electrochemical mechanical polishing (ECMP) of silicon carbide was carried out to study the effect of NaOH, NaNO3 and H3PO4 electrolytes on electrochemical oxidation of silicon carbide. NaNO3 of 0.6 mol/L was selected as the electrolyte in the ECMP process and so were the diamond-alumina mixed abrasive particles. The influence of load, rotational speed, voltage and particle size on the surface quality and material removal rate of ECMP silicon carbide was studied by using orthogonal experiment. With the optimized processing parameters, the combined polishing experiment can achieve a high-efficiency material removal rate of 20.259 μm/h in the rough polishing stage, and finally obtain the surface roughness of Sa 0.408 nm through precision polishing.

Using scallop as raw material and sodium stearate as modifier, the modified scallop powder was prepared by wet modification. Using single factor and response surface experiments to explore the effects of modification temperature, modifier dosage, and modification time on the modification effect of scallop shell powder. The scallop shell powder was characterized by Fourier infrared spectrometer, scanning electron microscope and X-ray diffractometer. The modified scallop shell powder and chitosan were made into a composite film, and the influence of the mass fraction of the modified scallop shell powder on the properties of the composite film was investigated. The experimental results showed that the best modification conditions of scallop shell powder were: Sodium stearate addition amount 2.53%, modification temperature 80.70 ℃, modification time 43.19 min. The activation of the fan shellshell powder produced under these conditions could reach up to 76.41%. Combined with characterization mapping analysis, sodium stearate was successfully incorporated onto the surface of shell powder, and the inter particle agglomeration of shell powder was weakened, and the prepared modified scallop shell powder showed good dispersion. Adding modified scallop shell powder could effectively improve the mechanical properties, light transmittance and water vapor barrier properties of the chitosan film. When the mass fraction of modified scallop powder was 1%, the performance of the composite film of modified scallop powder and chitosan was the best. At this time, the tensile strength of the film was 30.19 MPa, the elongation at break was 10.2%, the water vapor transmission rate was 35.1 g·h−1·m−2, and the light transmittance was 2.9 mm·%.

In order to promote the high-quality development of submarine cable and pipeline engineering construction in China, this paper designed and developed the submarine cable and pipeline information management system in the South China Sea based on relevant business requirements and framework technology. The results showed that the South China Sea submarine cable and pipeline information management system mainly included 6 modules: project approval, project supervision, data management, comprehensive display, statistical analysis and background management. It realized the functions of standardization of submarine cable and pipeline approval process, informatization of approval process, integration of online and offline supervision, visualization of spatial data and chartization of comprehensive statistical analysis. It could provide comprehensive technical support and auxiliary decision support for the whole process management of submarine cable and pipeline approval and the whole process supervision of construction.

The deformation and failure characteristics of slopes are different under different inclination and dip angles and their comparative analyses and studies are lacking. On the basis of fully considering the deformation and failure characteristics of hard rock slopes, hard rock similar materials are prepared, and the deformation and failure modes of slopes with different inclination and dip angles are analyzed with the bottom friction test method, and are analyzed with the PIVlab technology. The results show that there are obvious differences between the deformation failure mode and the failure range of down-dip and anti-dip slopes. Under the condition of 45° slope, when the dip angle of the down-dip slope changes from 30° to 45°, 60°, and 80°, the deformation and failure mode gradually evolves from slip-tensile to slight slip-bending (or slip-shear), no obvious deformation (overall stability), and to shallow toppling tensile crack. Under the condition of 45° slope and the anti-dip slope, the deformation failure mode gradually evolves from no obvious deformation under the conditions of 30° and 45° rock formation dip angles, and to dumping-cracking under the conditions of 60° and 80°. When the dip angle of the rock formation is steep, the damage range of the anti-dip slope is larger than that of the down-dip slope, and the turning end of the toppling bend is deeper. The results of PIVlab reflect that the speed and displacement vector characteristics of different positions are different under different structural slope conditions, which are consistent with the macroscopic observations, and the deformation zone characteristics are described according to the calculation results. This study can provide some reference for the stability evaluation and treatment design of similar slopes.

A 25-year-old female patient presented with numerous rashes on the trunk, external genitalia and inner thighs for 2 months. The patient had been diagnosed with HIV infection for 4 months, and treated with highly active antiretroviral therapy (HAART). Dermatological examination showed a large number of papules and nodules on the right areola, right intercostal, abdomen, pubis, labia majora, labia minora, perianal, and both inner thighs with partial macules papule, pustules, erosion and scab. Histopathology of skin lesion in areola and external genitalia indicated that there were inclusions of eosinophilic intracytoplasmic inclusions in the cytoplasm of the cells; verrucosa bodies (Henderson Peterson bodies) and some basophilic clear keratin particles and a small number of chronic inflammatory cells in the superficial dermis. Skin lesions gradually increased and enlarged with HAART. The patient was diagnosed with HIV infection and extensive intractable molluscum contagiosum. Then the patient was treated with microwave combined with imiquimod cream for external use, and psychological intervention and other comprehensive treatment. After 3 months of treatment, the skin lesions had basically subsided.

To determine the effects of extraction on the physicochemical properties and bioactivities in vitro of raspberry polysaccharides (raspberry polysaccharides, RAPs), water extraction, alkali extraction, acid extraction and enzyme extraction methods were studied. The microstructure of the polysaccharides and function groups were characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. The rheological properties of the polysaccharide were determined by HR-1 Discovery mixed rheometer. Additionally, the antioxidant activities were evaluated by DPPH, ABTS+ and hydroxyl radical scavenging activities, and the hypoglycemic activities were analyzed by α-amylase and α-glucoside inhibition. Furthermore, their hypidemic activities were evaluated by their oil, cholesterol and sodium cholate binding activities. The results showed that extraction yields, total polysaccharides and their molecular weights, constituent monosaccharides, proteins and phenolic compounds, rheological properties and binding capacities in vitro of the RAPs varied depending on the extraction method employed. RAPs obtained by enzyme extraction exhibited the highest molecular weight (5.80×105 Da) and apparent viscosity. Moreover, in terms of biological activity, they showed strong antioxidant activities and significant α-amylase and α-glucosidase inhibitory effects. And the raspberry polysaccharides obtained by enzyme extraction exhibited higher cholesterol binding capacity (22.92±0.41mg/g) and bile acid-binding capacity (83.55%±0.16%). In conclusion, compared with the other three methods, polysaccharides extracted by enzyme extraction showed stronger biological activity in vitro. The results from this study might provide a scientific basis for the isolation and application of RAPs in the pharmaceutical and functional food industries.

To solve the problems of poor surface quality and unevenness during the processing of TiBw mesh reinforced titanium matrix composites, the normal grinding forces of rotary ultrasonic grinding were studied. The motion law of abrasive particles in rotary ultrasonic grinding was analyzed, the normal grinding force model of rotary ultrasonic grinding TiBw mesh reinforced titanium matrix composites was established, and the model was verified by single factor grinding experiment. The results show that under certain spindle speed, feed speed, grinding depth, fixed grinding width, ultrasonic amplitude and ultrasonic vibration frequency, the normal grinding forces decrease with the increase of spindle speeds and increase with the increase of feed speeds and grinding depths, and the absolute values of relative error between the grinding experimental values and the model calculated values are within 6%. The model well predicts the normal grinding force during grinding of TiBw mesh reinforced titanium matrix composites, which verifies the effectiveness of the prediction model.

In this study, kelp juice, apple juice and sugar were used as the main raw materials, and Lactobacillus plantarum was applied as the fermentation strain, to develop a fermented kelp-apple compound juice beverage with excellent flavor and natural nutrition. Based on sensory scores, the process optimization of the compound fruit juice beverage was carried out through single factor experiments and orthogonal experiment design. The best formula and fermentation condition of the beverage were as follows: 1:2 volume ratio of kelp juice to apple juice, 3% sucrose addition, 8% Lactobacillus plantarum inoculation, fermentation time 24 hours and temperature 32 ℃. The result of antioxidant activity assay showed that the inhibition rate of DPPH free radical, ABTS+ free radical and total antioxidant capacity of fermented kelp-apple juice beverage were 73.20%, 36.05% and 0.774, respectively. On the whole, both kelp juice and apple juice showed certain antioxidant capacity. Fermentation improved the antioxidant capacity of kelp juice, but reduced the antioxidant capacity of apple juice. However, the fermentation of sole kelp juice had poor taste and flavor. The addition of apple juice and lactic acid produced by fermentation masked the fishy smell of kelp to a certain extent. On the other hand, the addition of kelp juice prevented decline of antioxidant capacity of sole apple juice fermentation. Fermentation of two juices could significantly improve the DPPH free radical scavenging capacity of beverage. This study solved the problem of fishy smell of kelp beverage, explored the antioxidant activity of kelp-apple juice beverage fermentation system, and would provide theoretical basis and practical guidance for the development of kelp-fruit juice beverage.

Xanthan gum (XG) and soybean protein isolate (SPI) were used as raw materials to prepare XG-SPI mixed gel by ultrasonic pretreatment and glucolactone induction. Rheological tests and scanning electron microscopy were used to study the effects of different concentrations of XG on viscoelasticity, self-healing ability, thermal stability and microstructure of SPI gel. Results showed that SPI gel was a typical viscoelastic material with strong frequency dependence. With the increasing of XG concentration (1%~5%), the elastic modulus and viscous modulus of the mixed gel increased, and the loss tangent decreased, and the gel strength increased. The addition of XG affected the self-healing ability of SPI gel, although the healing time was prolonged, the recovery rate increased. The SPI single gel which was heated (25~100 ℃) occurred a transition of gel-sol state and it structure was extremely damaged. Comparatively, the thermal stability of XG-SPI mix gel increased significantly. The microstructural changes of SPI single gel and XG-SPI mixed gel were not observed under electron microscope. The results of this study could provide important information for developing new soy protein isolate gels with improved quality.

In order to obtain the response law of pyrolytic chemical structure, seepage characteristics, and mechanical characteristics of oil shale to temperature, the structural evolution of functional groups in oil shale under different temperatures was qualitatively described and quantitatively analyzed by Fourier infrared spectroscopy (FTIR). Electronic universal testing and high-temperature triaxial penetration test were combined to reveal, the influence law of temperature on oil shale strength and permeability. At the same time, the pyrolysis, seepage, and mechanical properties of oil shale in other areas were compared. The results show that: The oil shale contains aliphatic compounds, aromatic compounds, oxygen-containing functional groups, and silicates. With the increase of pyrolysis temperature, the C—H bond of aliphatic compounds breaks first, and C=C breaks at high temperature. In addition, continuous fluctuations were also observed in the characteristic band intensities of functional groups such as C—O and Si—O. The compressive strength of oil shale gradually decreases, especially at a rapid rate from 300 ℃ to 500 ℃. When the temperature is between 20 ℃ and 400 ℃, the magnitude of the oil shale permeability in the stress-constrained state is small, and the highest is only 10-5 μm2. When the temperature is higher than 400 ℃, the oil shale permeability is larger. At the same time, the permeability decreases almost linearly with the increase of pore pressure, owing to the combined effect of gas slippage effect, adsorption effect, and effective stress. From the comparison with the pyrolysis, percolation, and mechanical properties of oil shale in other areas, it is seen that the evolution law of the pyrolysis characteristic of oil shale in different areas is relatively identical, while the mechanical strength and permeability results are quite different. It is considered that the main factors are organic matter content and maturity.

The Melut Basin is an important petroliferous basin in African Continent. The northern part of the basin is characterized by far-source oil accumulation with the oil generation in the Lower Cretaceous and the oil accumulation in the Paleogene. Clarifying the formation conditions and controlling factors of the far-source oil accumulations is the key to improve the exploration success rate and seek new potential areas of far-source oil accumulations in the Melut Basin. Based on the study of regional petroleum geological conditions and the analysis of key oil accumulations, the formation conditions, types, characteristics and potential exploration areas of far-source oil accumulations in the Melut Basin have been systematically studied. The results show, ①The north Melut Basin develops two types of far-source oil accumulations with different hydrocarbon charging patterns and accumulation modes in the Paleogene Yabus Formation, the far-source fault-lithology combination oil accumulations within the oil kitchen and the far-source fault-block oil accumulations outside the oil kitchen; ②The formation of far-source oil accumulations of the Yabus Formation inside oil kitchen depends on the coupling of three geological conditions, that is, the "two strong and one weak" three-stage rifting cycles, creating conditions for the formation of the Paleogene Yabus-Adar far-source reservoir-caprock combination; the development of oil-rich sag, providing necessary oil supply for the Yabus far-source traps; and the multi-stage rifting activities, providing vertical migration pathways for hydrocarbon charging in the Yabus far-source traps; ③The far-source oil accumulations inside oil kitchen are mainly charged by the vertical hydrocarbon infilling through the oil-source faults, and the oil-source faults are the main controlling factor for the hydrocarbon accumulation. The identification of oil-source faults and the evaluation of the lateral sealing capability of trap-controlling faults are the key elements for the far-source fault-block traps inside oil kitchen; ④The far-source oil accumulations outside oil kitchen are mainly charged by lateral hydrocarbon infilling from the oil-rich sag. The transportation ridges formed by sand-rich strata, fault blocks and paleo-uplifts control the hydrocarbon accumulation of far-source traps outside oil kitchen. The identification of transportation ridges and the study on the hydrocarbon charging extent are the main evaluation focus of far-source traps outside oil kitchen. The research results successfully guided the exploration deployment and in-depth exploration of far-source oil accumulations in the Melut Basin, and have a great implication on the exploration of far-source oil accumulations in the other petroliferous basins.

The Triassic silty mudstone is encountered in the Sichuan-Tibet Railway, when it passes through Gongjue County in Tibet of Chian, and the rock is prone to cause large deformation under the condition of high geo-stress. In this study, we carried out the triaxial rock compression and triaxial creep tests under different confining pressures. Combined with the PFC numerical simulation, we have also studied the creeping characteristics and long-term strength of the silty mudstone under different confining pressures. The results show that the rheology of the Gongjue silty mudstone is characterized by the Nishihara creep model. With the continuous increase of the confining pressure, under the conditions of the creep and conventional triaxial tests, the silty mudstone specimens all undergo transition from tensile-shear failure to single-shear failure. The angle between the shear fracture surface and the horizontal line gradually decreases, and the number of microcracks decreases. Compared with the conventional triaxial test, the creep test has a wider range of influence on the crush zone caused by tensile stress. Under the conditions of high confining pressure, the silty mudstone is more prone to rheology. The numerical simulation results show that when the confining pressure increases, the axial strain, lateral strain and volumetric strain will increase, while the number of microcracks decrease. There is a linear increasing relationship between the instantaneous elastic modulus and the viscoelastic coefficient with the confining pressure, the viscoelastic modulus has a logarithmic growth relationship with the confining pressure, and the viscoplastic coefficient has an exponential growth relationship with the confining pressure. Under long-term loading, the long-term strength phase of the rock is lower than the instantaneous strength.

CO2 huff and puff experiments of different injection parameters, production parameters and soaking time were carried out on large-scale cubic and long columnar outcrop samples to analyze dynamic characteristics and influencing factors of CO2 huff and puff and the contribution of sweeping mode to recovery. The experimental results show that the development process of CO2 huff and puff can be divided into four stages, namely, CO2 backflow, production of gas with some oil, high-speed oil production, and oil production rate decline stages. The production of gas with some oil stage is dominated by free gas displacement, and the high-speed oil production stage is dominated by dissolved gas displacement. CO2 injection volume and development speed are the major factors affecting the oil recovery. The larger the injected CO2 volume and the lower the development speed, the higher the oil recovery will be. The reasonable CO2 injection volume and development speed should be worked out according to oilfield demand and economic evaluation. There is a reasonable soaking time in CO2 huff and puff. Longer soaking time than the optimum time makes little contribution to oil recovery. In field applications, the stability of bottom hole pressure is important to judge whether the soaking time is sufficient during the huff period. The oil recovery of CO2 huff and puff mainly comes from the contribution of flow sweep and diffusion sweep, and diffusion sweep contributes more to the oil recovery when the soaking time is sufficient.

The undeveloped low-permeability oil reserves of the Liushagang Formation in the Beibu Gulf Basin are large, but the reservoir quality is poor. The existing classification standards for low-permeability reservoirs cannot meet the needs of fine reservoir evaluation and offshore development.Based on the experiments of constant rate mercury injection, high pressure mercury injection, NMR and seepage mechanism, this paper comprehensively analyzed the micro-pore structure and seepage characteristics, and optimized six kinds of reservoir evaluation parameters: reservoir quality index, fractal dimension of pore structure, mainstream throat radius, mean throat radius, percentage of movable fluid and change rate of threshold pressure gradient, meanwhile, the classification limit of various characterization parameters were determined by integrating with the reservoir quality index, reservoir seepage ability evaluation factors and specific productivity index constraint parameters. A comprehensive evaluation criterion for low-permeability oil reservoirs is established based on the Grey Relational Analysis method, which is divided into Ⅰ, Ⅱa, Ⅱb, Ⅲ and Ⅳ from good to bad.Carried out the grading evaluation of low-permeability reserves and the research results provide a theoretical basis for the analysis of the development potential, the research direction of the low-permeability reserves in Beibu Gulf Basin.The results show: types Ⅰand Ⅱa are relatively high-quality low-permeability reserves and have been put into large-scale development.Types Ⅱb and Ⅲ are extra-low-permeability reserves and are difficult to develop, which need to be formulated for experimental development by reasonable technical measures and development models.

According to the abnormal fracture phenomenon of 87MnSi steel wire rod for bridge cable， the evolution of microstructure and mechanical properties during production processing were systematically analyzed. The results show that the microstructure of the rod is composed of pearlite and a small amount of proeutectoid ferrite， and the cementite lamellae are randomly distributed. After cold drawing， the cementite lamellae are rotated or fibrotic， and some cementite are broken and dissolved， the dissolution amount is 1.40wt.%（9.69%）. After ho-dip galvanizing， the dissolved cementite is spheroidized. In the process of cold drawing， hot-dip galvanizing and stabilization treatment， the microhardness of wire rod （329.8HV） increases （450.2HV） firstly， then decreases （447.9HV） and increases （474.8HV） finally. The cementite dissolved in the cold drawing process increases the hardness of the steel wire to 468.3HV， while the spheroidized cementite in the hot galvanizing process decreases the hardness to 439.8HV， and deteriorates tensile property. When the degree of spheroidization of cementite on the edge is obvious， the microstructure and mechanical properties of the steel wire inside and outside are greatly different， and the fracture is eventually caused by uneven force during stabilizing treatment.

In the Chinese strong-flavor baijiu (CSFB) fermentation ecosystem, the caproic acid-anabolism of caproic acid-producing bacteria (CPBs) is very important for improving the fermentation quality of CSFB. Therefore, it is necessary to thoroughly understand the types of CPBs and their caproic acid-anabolism characteristics. This minireview introduces readers to the diversity, phylogenetic relationship, physiological and metabolic characteristics, and caproic acid synthesis mechanism of CPBs isolated from the CSFB fermentation ecosystem as well as their synergistic metabolic relationships with other CPBs or non-CPBs. This paper provides a reference for understanding the in-situ caproic acid-anabolism pattern of CPBs from the CSFB fermentation ecosystem, and further provides a theoretical basis for the future targeted application of CPBs in CSFB fermentation and for CPBs culture engineering for the synthesis of high value-added caproic acid.