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X-ray fluorescence spectroscopy analysis is a major method for quantitative analysis of metal elements in coal. The accuracy of background subtraction directly affects mineral metal sorting. As traditional background subtraction methods feature low background fit and large diffraction peak area errors, this study proposes an optimized method of complex wavelet transform with inverse derivative fitting for background subtraction. We obtained a simulated background spectral line through reversed peak searching and separated the overlapping peaks and valleys using Largrange's interpolation to push the simulated background close to the actual background. We then decompose and reconstruct the simulated background spectral line through complex wavelet transform to accomplish background subtraction of XRF analysis. We used the optimized method of complex wavelet with inverse derivative fitting for background subtraction of the simulated XRF spectrum and the real XRF spectrum, and compared with Continuous Wavelet and Dual-tree Complex Wavelet. The experimental results indicate that the optimized method outperforms the traditional methods in background subtraction accuracy, with less than 1 % of diffraction peak area error and less than 0.1 % of background area.

ObjectivesThe natural draft cooling towers with flue gas injection (NDCT-FGI) is a crucial retrofitting technique for enhancing the efficiency of thermal power plants. However, its operational impacts on existing systems are significant and cannot be overlooked. Therefore, the current status of NDCT-FGI technology and its problems in operation were analyzed, and the countermeasures were put forward.MethodsThrough comprehensive analysis of the existing research, the causes and formation mechanism of environmental impact, cooling tower corrosion, and deterioration of circulating cooling water quality caused by the technical transformation of NDCT-FGI were discussed.ResultsThe protective distance can be reasonably set by the simulation results of flue gas emission trajectory and pollutant landing concentration by computational fluid dynamics (CFD). Installation of baffles at the tower top can prevent flue gas washdown during the extreme weather conditions. Different anticorrosive coatings are recommended for various parts of the cooling tower to extend its service life. To control and optimize cooling water quality, the advanced water treatment techniques are necessary for optimizing chemical dosing, and the management of effluent and makeup water must be carefully controlled to ensure operational sustainability.ConclusionsBy implementing appropriate and effective countermeasures, the negative impacts of NDCT-FGI retrofitting can be mitigated, thereby enhancing both the environmental and economic benefits for thermal power plants.

The existing intelligent anti-jamming methods based on deep reinforcement learning are applied to space-ground TT&C and communication links, in which the deep neural network used for decision-making has a complex structure, and the resources of satellites and other vehicles are limited, making it difficult to independently complete the timely training of complex neural network under the constraints of limited complexity, and the decision-making of anti-jamming cannot converge. Aiming at the above problems, an intelligent anti-jamming decision algorithm based on proximal policy optimization was proposed, which deployed the decision-making neural network and the training neural network in the vehicles and the ground station, respectively. The ground station conducted the optimal offline training based on the empirical information feedback from the vehicles, and assisted the decision-making neural network in parameter updating, thereby achieving the effective selection of anti-jamming strategies while satisfying the resource constraints of the vehicles. The simulation results demonstrate that the convergence speed of the proposed algorithm is increased by 37%, and the system capacity after convergence is increased by 25%, compared with the decision algorithms of policy gradient and deep Q-learning.

To reveal the dynamic load distribution characteristics of planetary roller screw mechanism under the high-speed operating conditions, based on the spiral surface equation and deformation coordination relationship, a static contact force calculation method of the roller-screw and roller-nut thread at the contact point is proposed, and a formula for calculating the contact angle after bearing is derived. On this basis, further considering the inertial force generated by using high-speed operation, a dynamic load distribution model for planetary roller screw mechanism thread was established. By comparing with the finite element contact model of planetary roller screw mechansim, the error is below 5%, which verifies the correctness of the model established. Finally, the influence of the parameters such as screw speed, axial load, pitch, and tooth flank angle on the distribution of dynamic load was analyzed. The results show that the inertia force causes the roller to have a tendency to move closer to the nut and away from the screw resulting in a decrease in dynamic contact force on the roller screw side and an increase in dynamic contact force on the roller nut side. The degree of uneven distribution of dynamic load is positively correlated with the screw speed and pitch, and negatively correlated with the tooth side angle. The size of axial load has a significant impact on the distribution of dynamic load.

In this paper， a steel plant with high pulling speed thin thickness slab continuous casting process as the object is studied， the specific process parameters of the pulling speed of 5.5 m/min， pouring temperature of 1 544 ℃， crystallizer water pressure of 15.6 Pa， the cooling water temperature of 39.1 ℃， and the inverted taper of the crystallizer 7.5 mm and so on.In the process of on-site continuous casting， it was found that the risk of slag rolling increased and the casting bond alarm occurred frequently， the conventional slags and non-Newtonian fluid mold flux with only shear-thinning properties could not effectively in solving these problems .With the mold flux of medium carbon steel on-site as the original mold flux ， combined with additives such as MgO and SiC ， a new type of protective slag with strong shear-thinning properties and high surface tension is prepared. The shear thinning properties， surface properties and microstructure of mold flux were detected and studied by rotating cylinder method and other methods. The results show that with the increase of SiC content， the shear thinning property， contact angle， surface tension and interface tension of the mold flux all show the trend of increasing first and then decreasing， the content of C-O bond and C-Si bond increases， and the degree of molecular polymerization increases . When the SiC content is 0.98%， the shear thinning property is the strongest， and the contact angle， surface tension and interfacial tension are the largest. This enables the mold flux to meet the viscosity requirements at different shear rates， thus effectively suppressing the crystallizer slag rolling behavior and reducing the risk of bond leakage.

【Objective】In order to solve the problem that it is difficult to make the temperature sensor of the Photonic Crystal Fiber (PCF) with Surface Plasma Resonance (SPR), a D-structure PCF temperature sensor is proposed. The micro-structure and arrangement of the air hole are also designed. The method of coating the polishing surface of the optical fiber with gold layer is used to stimulate the SPR of the optical fiber.【Methods】Ethanol is used as a temperature-sensitive material, and the temperature-sensitive effect is used as the temperature sensing mechanism to achieve the effect of temperature sensing. The finite element analysis method is used to simulate the thickness of the gold layer and the size of the elliptical air hole of the fiber respectively. The coupling characteristics between the core mode and the surface plasma mode are analyzed under different conditions, and the structure of the sensor is optimized.【Results】The temperature characteristics of the sensor are simulated. In the range of -80~80 ℃, the sensitivity of the sensor is 3.4 nm /℃, and the linearity is better than 0.969 63.【Conclusion】The temperature sensor designed in this paper has a wide temperature detection range, satisfactory sensitivity, and linearity, which can be used for real-time temperature monitoring in industrial, agricultural, and medical fields.

Objective To address the difficulties faced in the industrial design of rail transit passenger vehicles, it is necessary to integrate innovative industrial design thinking and concepts to establish a comprehensive method for modular and pedigree applications in rail transit passenger vehicle design. Method First, a modularization analysis of passenger vehicle design components is conducted, dividing the compartment into fixed, optional, and custom modules, and categorizing the exterior into color and shape modules. Then, a pedigree analysis of passenger vehicle design contents is performed, establishing an industrial design pedigree from three dimensions: design requirements, evolutionary context, and product characteristics. Finally, based on passenger vehicle design characteristics, a passenger vehicle industrial design method for modularization and pedigree comprehensive applications is constructed, comprising three steps: sorting out modules based on design requirements, adjusting modules oriented by evolutionary context, and organizing modules based on product characteristics. Result & Conclusion The industrial design method is applied to a passenger vehicle design by a subsidiary manufacturer of CRRC (China Railway Rolling Stock Corporation). The design example verifies the feasibility of the constructed method. The modularization design allows for quick and flexible adjustments of design contents according to user needs, while pedigree design enhances design coherence and systematicity. Combining these approaches enables the completion of both exterior and interior passenger vehicle designs within a shorter design cycle, thereby improving design quality and reflecting brand features.

The helix surface model of planetary roller screw mechanism (PRSM) is established by utilizing the parametric equations of space surface according to the structural features of screw, roller and nut. The helix surface model of PRSM is improved in consideration of the PRSM assembly relationship. The normal vector equations of helix surfaces are obtained based on the helix surface model. The meshing clearance models of PRSM in axial, radial and circumferential directions are built considering the movement direction of parts utilizing surface meshing conditions. The influence of structural parameters on the meshing clearance of PRSM is also analyzed. The results show that the meshing points between the roller and the screw in three directions are not in the middle diameter. The meshing points in the three directions of the roller and the nut are in the middle diameter of the roller. The pitch, tooth angle and tooth thickness of the thread all have an influence on the meshing clearance of PRSM. Only by increasing the tooth thickness of the thread can the meshing clearance in the three directions be reduced at the same time. The pitch and tooth angle should be selected properly to meet the practical requirements.

【Objective】 Winter wheat in Northern China is often rotated with other crops which are expected to have a legacy effect. This paper aims to study the effect of different tillage and preceding crops on soil nutrients, yield and water use efficiency of the winter wheat. 【Method】 The field experiment consisted of a rotary tillage (RT) and a no-tillage (NT). The preceding crops for each tillage were corn (MW) or soybean (SW). During the experiment, we measured the changes in soil nutrients, soil water content, water and fertilizer use efficiency, and yield of the wheat. 【Result】 For the same preceding crop, non-tillage increased soil water content compared to rotary tillage; under the same tillage, soil water content with maize as the preceding crop was higher than that with soybean as the preceding crop. In all treatments, soil nutrients decreased with soil depth. In the 0-50 cm soil layer, NTSW increased soil organic carbon, soil total nitrogen and nitrate nitrogen by 4.14%-13.54%, 35.51%-54.44% and 55.75%-112%, respectively, compared to the RTMW. RTMW had the highest available phosphorus and potassium in the 10-50 cm soil layer. The RTSW had the highest ammonium nitrogen in the 0-50 cm soil layer, 13.39%-20.64% more than that in the RTMW. The winter wheat in NTSW had the highest spike numbers, spikelet numbers, thousand-grain weight; and its grain yield was 16.62% higher than that of RTMW. The NTSW had the highest water use efficiency, 8.67% more than that of RTMW. The NTSW had the highest nitrogen, phosphorus and potassium use efficiency. 【Conclusion】 The NTSW facilitated nutrient accumulation in the winter wheat field. It had the highest water and fertilizer use efficiency and increased grain yields the most as a result.

Objective Debris flow from the Hanjia gully develops on the left bank of the source area of the Fujiang River, Fenghe Village, Xiaohe Town, Songpan County, China. In recent years, debris flows have occurred frequently, and the largest debris flow occurred in August 2022, which seriously threatened the lives and properties of villagers in the Hanjia gully. Existing prevention and control engineering methods have decreased in effectiveness or even become ineffective. Currently, researchers have set a variety of extreme rainfall conditions and used FLO-2D to analyze the hazards of debris flow, based on which the governance effect of debris flow prevention and control engineering can be evaluated. However, there are few reports on how to improve the prevention and control engineering and evaluate the effect of the improved prevention and control engineering when the existing prevention and control engineering is ineffective. Methods To reduce damage to the Hanjia gully, the characteristics as well as prevention and control status of the debris flow in/from this gully were determined using remote sensing interpretation, field investigation, and FLO-2D numerical simulation; subsequently, improved prevention and control engineering was proposed. The hazard of debris flow before and after the improvements in prevention and control engineering under different rainfall frequencies were studied to analyze the effectiveness of the improved prevention and control engineering. Results The results show that the Hanjia gully is located in the "8.8" Jiuzhaigou earthquake disturbance area, the static reserves of post-earthquake landslides and collapses are about 49.79 × 104 m3, and the debris flow sources are abundant, which leads to frequent debris flow during heavy rainfall. The high-hazard area is concentrated in the No. 1 retaining dam, and Fenghe Village and Pingsong Highway are in the low-hazard area under a rainfall event occurring every 10 years, and the existing prevention and control engineering can effectively prevent the debris flow disaster. Under a rainfall event occurring once in 50 years, Fenghe Village is in the high-hazard area of debris flow. The debris flow rushes out of the drainage channel and destroys the Pingsong Highway. The maximum mud depth in the accumulation area increases from 1.41 m to 3.14 m, the maximum velocity increases from 2.4 m/s to 3.65 m/s, and the accumulation area increases from 0.28 × 104 m2 to 5.41 × 104 m2. However, the existing prevention and control engineering methods cannot meet these requirements. After adopting improved prevention and control engineering, such as multistage retaining dams and cutting and straightening of drainage channels, the flow velocity of the debris flow in front of the two additional retaining dams becomes lower than that before the improvement, and the depth of mud in front of the additional retaining dams becomes higher than that before the improvement. The maximum velocity of the debris flow within 100 m of Dam No. 3 decreases by 29%, and the maximum mud depth increases by 413%. The maximum flow velocity in the first 100 m of Dam No. 2 decreases by 21%, the maximum mud depth increases by 175%, the maximum mud depth in the accumulation area is 3.9 m, and the maximum flow velocity is 3.4 m/s. The accumulation volume of debris flows is reduced by 50.2%, and the accumulation area is reduced by 86%. Conclusion Improved prevention and control engineering can effectively reduce the solid mass of debris flows and guide debris flow to discharge along drainage channels. The high-hazard area of the debris flow is concentrated in the drainage channel, and the control effect of the debris flow is remarkable. Significance The research results provide a scientific method for evaluating the effectiveness of debris-flow control engineering improvements and offer technical support for local debris-flow early warning systems.

At present, the society is in an era of rapid development of science and technology, and the rapid development of wireless communication technology has not only promoted the digital transformation of industry, transportation, medical and other fields, but also continuously upgraded wireless communication networks, trying to move from wired to wireless. With the continuous evolution of computer technology and wireless communication technology, many application scenarios require highly reliable transmission in a wireless environment. Especially in the fields of modern industrial automation and autonomous driving, the demand for highly reliable transmission is more urgent. 5G technology was delved into, which was one of the most advanced wireless transmission technologies in the industry, focusing on multi-channel redundant transmission technology within 5G systems. The key points of the technology in terms of application background, technical principles and technical route were summarized. In terms of application background, the practical application requirements of 5G redundant transmission in wireless scenarios such as modern industrial automation and autonomous driving were highlighted. In terms of technical principles, the relevant research was summarized and sorted out from the end-to-end multi-channel redundant transmission of services, the analysis of the technical principles of 5G multi-channel redundant transmission were focused on, and its unique advantages in improving transmission reliability were explained. In terms of technical routes, the development direction of 5G multi-channel redundant transmission technology and various possible implementation paths were comprehensively considered. Finally, the difficulties and challenges of the future development of 5G multi-channel redundant transmission technology were pointed out, and its future development trend was discussed, so as to better understand the key role and prospect of 5G redundant transmission technology in the field of wireless communication.

Carbonate reservoirs are often stimulated by acidizing and acid fracturing techniques， but the microstructure of the rock surface is corroded and destroyed after acid etching， and the mechanical properties of the rock are changed significantly， which further affects the final stimulation effect. The experiment on the mechanical properties， the study on surface morphological characteristics by scanning electron microscopic （SEM）， and the microscopic pore structure characterization by nuclear magnetic resonance （NMR） are carried out before and after limestone acid etching to clarify the influence of acid etching on the mechanical properties and microscopic pore structure changes of limestone. The results show that acid etching softening layers with a certain thickness of about 11.61 μm appear on the rock surface after acid etching. Remarkably， the compressive strength， elastic modulus， and surface hardness of limestone are all reduced to about 40% before acid etching due to the acid etching softening layers. Dissolved pores of different sizes are formed inside the rock surface after acid etching and stress concentration is induced around the dissolved pores， changing the stress distribution of the acid etching softening layers. Under high closure stress， the dissolved pores are easier to crush deformation or collapse failure， which is also the main reason for the change of mechanical properties of acid etching softening layers. According to the T2 spectrogram of NMR， it is found that there is the largest change in the number of pores with pore sizes between 1 nm and 1 μm， and the acid dissolution alters the internal pore structures of the acid etching softening layers， hence further affecting the mechanical properties of rock after acid etching.

In this study, the changes in the amylose content, crystalline structure, Fourier transform infrared (FTIR) properties, pasting properties, and rheological properties of potato starch were explored after radio frequency (RF) treatment at different polar plate spacings (90, 100, 110, 120, and 130 mm). The appropriate RF parameters for 3D printing of potato starch gels were determined. The results revealed that under low plate spacing, the content of amylose decreased and the crystalline form of starch transformed from B-type to C-type. We found that the starch gel with RF treatment at a plate spacing of 90 mm had the best morphology in terms of transparent line uniformity and high retention rate. To sum up, we can conclude that RF treatment at low polar plate spacings is an effective method for preparing 3D printed starch gels.

A better understanding of the spatiotemporal dynamics of species composition and biodiversity provides significant insights into the distribution patterns of biodiversity and the prediction of biodiversity fate in a global change context. However, how species and phylogenetic diversity change along elevational gradient with temporal scale in mountain ecosystems is still unknown. In this study, we used census data (2004, 2008 and 2013) of an elevational transect (elevational range 960 - 2 878 m) covering eastern and western slopes of Gaoligong Mountains, SW China, to investigate the spatiotemporal dynamics of forest arbor layer (DBH≥5 cm) species composition, species diversity and phylogenetic diversity. The results were as follows: (1) Species diversity was hump-shaped along the elevational gradient, while the phylogenetic diversity increased with increasing elevation. Clustering phylogenetic structure was observed at low elevations, and over dispersed or random structure was detected at high elevations. (2) Overall, temporal species and phylogenetic beta diversity analysis showed no significant difference among these three investigation time points. However, we found a higher clustering of phylogenetic structure along the temporal scale. (3) Spatial beta diversity showed that there was a significant loss of species at low elevations (960 - 1 381 m) on the eastern slope, where the vegetation had been disturbed or completely converted into farmland. The main lost species including Terminalia chebula, Quercus acutissima, Pistacia weinmanniifolia, Hovenia acerba and Ilex wattii. In contrast, the change in the western slope was mild at low elevations, only observing species abundance increasing, which including Cyclobalanopsis oxyodon, Symplocos chinensis, and Taiwania cryptomerioides. Therefore, we speculated that the dynamic changes in species and phylogenetic diversity of the arbor layer of subtropical evergreen broadleaf forest might be related to communities succession process and climatic change in middle and high elevations, while the communities at low elevations were seriously impacted by human activities in Gaoligong Mountains. The results deepen the understanding of the mechanisms of plant community dynamics in Gaoligong Mountains, and provide new insights to guide precise conservation strategies in the region.

Urban agglomerations are the main spatial carriers of national and regional urbanization development. The study of their spatial association networks is of great significance for optimizing the allocation of urban resources, promoting the process of regional integration, and facilitating the high-quality development of urban agglomerations. The Yangtze River Delta urban agglomeration (YRDUA) is one of the most economically active regions in China. Its spatial association network structure was the main feature of economic and social development in China's "14th Five-Year Plan." Based on the perspective of flow spaces in terms of both the city and township scales, multi-source data were used in this study and included online car-hailing origin-destination travel data, combined with complex network models and a quadratic assignment procedure, to analyze the structural characteristics and driving mechanism of the spatial association network of the YRDUA. Results show that: 1) spatial association network based on online car-hailing flow in the YRDUA has spatial dependence and hierarchical characteristics, and intensities of network association are mostly coupled with levels of economic development; 2) spatial association network in the YRDUA displays spatial spillover effects, leading to an overall pattern of high equilibrium in southern development and strong single-point development capacity in the north; 3) the structural features of spatial association network in the YRDUA differ between townships and urban scales, with some high-level townships in certain transportation networks failing to exert their driving role at the urban level; and 4) economic development status, population vitality, the level of urban construction, and administrative division ownership and geographical location differences between townships have significant impacts on the spatial association network structure in terms of the township scale. The differences in administrative divisions are most important. Online car-hailing travel data were used in this study to effectively supplement the links between township streets within and between cities. This data also revealed intercity links. Thus, the development characteristics of spatial units on different scales were reflected, and research and social management needs were satisfied on a fine scale. In addition, by introducing spatial big data and analyzing the influence mechanism from various aspects, such as socioeconomics, the driving factors of the spatial network of urban agglomerations were systematically identified at the small-scale level, which will help with more reasonable planning within the city and play a role in the development of urban agglomerations by enhancing the attractiveness of individual cities. This study expands the research perspectives on the cooperative development of urban agglomerations on different scales, providing theoretical references and practical support for the promotion of the coordinated development of urban agglomerations as a whole.

Under the background of “dual carbon”, new energy sources have begun to be connected to the grid on a large scale. However, the randomness and volatility of new energy generation significantly impact the power grid, making it urgent to build a new power system. As the cornerstone of the power system, traditional thermal power will transform into a basic security and system regulatory power supply, providing reliable capacity, peak regulation and frequency modulation and other auxiliary services. The flexible transformation of thermal power units has become an inevitable choice. The phased objectives, difficulties, and challenges of building a new power system were analyzed, along with the problems encountered in the flexible transformation of thermal power units at the present stage. Combined with thermal power operation data, the technical ways of configuring energy storage equipment for thermal power units were analyzed. The research shows that there are several issues in building a new power system, such as power system instability, difficulties in transforming traditional thermal power, high energy consumption, and environmental pressures. The flexibility transformation of thermal power units faces challenges such as insufficient peak regulation capacity, high operation costs, slow load response, high operation energy consumption, safety concerns, etc. The integration of thermal power and energy storage will bring better economic and environmental benefits.

【Objective】 Black soil is widely distributed in northeastern China and other countries. Machinery operations in agricultural production in these regions has resulted in soil compaction. In this paper, we investigated the impact of soil compaction on growth, yield, and nitrogen use efficiency of maize in the black soil. 【Method】 The field experiment compared three soil compactions: low compaction (C1), moderate compaction (C2) and high compaction (C3). For each compaction, there were two fertilization treatments: nitrogen fertilization (F) and no fertilization (F0). In each treatment, we measured the growth, yield and nitrogen use efficiency of the maize. 【Result】 Increasing soil compaction significantly reduced leaf area index (LAI) and plant height of the maize. Nitrogen fertilization affected plant height significantly but did not impact LAI at significant levels. Soil compaction also impacted grain yield significantly, with the high and moderate soil compaction reducing grain yield by 24% and 10%, respectively, compared to the light compaction. Soil compaction and nitrogen fertilization combined to impact nitrate in the soil. Elaborated soil compaction inhibited maize growth, reduced nitrogen absorption, leading to an increase in residual nitrate nitrogen in soil as a result. Soil compaction also influenced nitrogen uptake and its subsequent translocation in the above-ground part of the maize. Nitrogen fertilization increased nitrogen absorption by the crop significantly, but reduced nitrogen use efficiency, especially in the high compaction treatment. 【Conclusion】 Elaborated compaction of the black soil due to machinery operations severely inhibited growth, absorption and use of nitrogen of the maize, thereby leading to an increase in residual nitrate nitrogen in the soil and reducing grain yield as a result.

The aircraft AC power generation system is the main source of power for the whole aircraft, so a complete safety analysis is required. Traditionally safety analysis pays less attention to the security problems caused by nonlinear interaction between system components. Especially when the support data of the developed model is insufficient, there is a risk of analysis omission. According to the basic characteristics of the power supply conversion process of AC power generation system, this paper constructs a safety control structure chart and identify unsafe control action(UCA) based on the STPA method, and introduces the failure model and effect analysis(FMEA) of similar system to analyse the UCA cause factor and cause scenario. Using formal tool of timed automata theory, the system modeling and verification are carried out. The correctness of this methods is confirmed by expert evaluation and accident comparison. The result shows that the introduction of STPA based on traditional safety analysis methods can effectively identify unsafety control action and the causes of accident, which can be an effective supplement to the traditional method.

Traditional Chinese medicine (TCM) syndrome differentiation, as the core of the traditional Chinese medical system, has played an indispensable role in guaranteeing the health of the Chinese nation for thousands of years. Recently, with the collaborative promotion of multiple departments, the TCM technology innovation capability of China has been continuously enhanced. The integration of TCM syndrome differentiation with artificial intelligence AI, big data, and other fields has made new progress. Engineering frontier methods and technologies have provided an effective route for breaking through the theoretical bottlenecks of TCM syndrome differentiation. Against the backdrop of the modernization and intelligent development of TCM diagnosis in the new era, this study summarizes the fundamental theories, basic processes, and key technical links of AI-assisted TCM syndrome differentiation. The key technical links include multimodal data fusion, symptom correlation analysis, syndrome quantification, syndrome reasoning, and large-scale TCM models. It also expounds on the research ideas and development status of each link and summarizes the challenges faced by AI-assisted TCM syndrome differentiation. For instance, publicly available data are insufficient and have a poor quality; syndrome differentiation models are inadequate, have poor universality, and lack interpretability and consistency; and the evaluation of syndrome differentiation model results is limited and lack credibility. Therefore, the following suggestions are proposed for reference: (1) strengthening data integration and quality control; (2) deeply integrating AI with TCM syndrome differentiation to enhance model interpretability; (3) developing large language models for the subdivisions of TCM; (4) strengthening the construction of intelligent TCM talent teams and encouraging cooperation among experts in multiple fields; and (5) improving international standards and regulations to strengthen international cooperation and exchanges. These efforts aim to provide references for the technological exploration and innovation of AI-assisted TCM diagnosis and treatment.

[Objective] Atriplex canescens is a high-quality xerophytic shrub widely introduced in desertification control areas, and stubble is a main management measure for desertification control. Revealing the adaptability and compensatory growth mechanism in the recovery process after stubble can provide theoretical support for developing A . canescens into a high-quality feed in desert areas. [Methods] In this study, 5-year-old A . canescens plants were used as object. Through stubble treatment, plant height, crown width, photosynthetic reaction, leaf water potential, leaf hydraulic conductivity, and water use efficiency were measured during the recovery process of A . canescens, and the relationship between functional traits was discussed. [Results] (1) The plant height, crown width, and aboveground biomass of A . canescens after stubble were recovered to the pre-stubble state after a growing season. (2) The leaf water potential, leaf hydraulic conductivity, water use efficiency, and photosynthetic parameters of the stubble plants were higher than those of the control plants. (3) Linear fitting analysis showed that the midday leaf water potential and stomatal conductance of the stubble plants were significantly positively correlated with the growth rate. [Conclusion] A . canescens had good compensatory growth ability after stubble. In the early stage of recovery growth, the flat stubble plants showed higher compensatory growth ability and typical acquisition strategy, and then turned to conservative strategy with the decrease of hydraulic condition in the later stage. Stubble plants allocated more biomass and resource to the growth of aboveground parts such as branches and leaves, and the later resource allocation turned to the growth of underground parts.

SiO2/g-C3N4 composite aerogel material with high specific surface area and porous structure was prepared by direct ink writing 3D printing. The micro morphology and porous structure of the material were characterized，and its adsorption and catalytic degradation properties for high concentration Rhodamine B（RhB） in wastewater were tested. The research results showed that the 3D-printed SiO2 aerogel has a specific surface area of 482.1 m2/g，a nano porous structure with a pore volume of 1.195 cm3/g，and a good adsorption performance for RhB. The porous structure of SiO2/g-C3N4 composite aerogel prepared by modifying with g-C3N4 had little change and maintained high adsorption performance，and the removal rate of RhB（100 mg/L） by 3D-printed composite under UV could reach more than 99%. After five cycles of testing，the removal rate of RhB by SiO2/g-C3N4 composite aerogel was still 92.98%，compared with 55.75% for 3D-printed SiO2 aerogel. According to the mechanism analysis，g-C3N4 in the composite could absorb light energy and generate photogenerated electron-hole pairs ，the electron-hole pairs could react with H2O and O2 to produce oxidizing active substances superoxide radicals，and finally participated in the photocatalytic oxidation and reduction reaction to catalyze the degradation of RhB macromolecules. The high specific surface area of the 3D printing structure realized the large reaction contact area between the catalyst and RhB，and improved the photocatalytic degradation efficiency and cycle stability of the composite.

Objective To analyze the current situation and influencing factors of work engagement of neurology nurses. Methods Using the convenient sampling method, a cross-sectional survey was conducted among nurses in the department of neurology in a Class III and Class A general hospital in Beijing from April to May 2022. The self-designed general data questionnaire, the work engagement scale and the Chinese version of the perceived stress scale were used to survey the nurses in the department of neurology. Results In this study, a total of 660 questionnaires were distributed and 630 were recovered, with a recovery rate of 95. 45%. Totally 630 questionnaires were valid, with an effective rate of 100. 00%. Of the 630 neurology nurses, 34 were male (5. 40%) and 596 were female (94. 60%). The score of work engagement of 630 neurology nurses was (35. 15 ± 5. 34), and the data difference was statistically significant (P＜0. 05). The results of univariate analysis showed that there were statistically significant differences in the scores of work engagement of neurology nurses in terms of age, employment relationship, technical title, working years and children's situation (P＜0. 05). The total score of perceived stress of neurology nurses was (36. 76 ± 8. 10), and the total score of work engagement was positively correlated with the score of sense of loss and perceived stress (P＜0. 05), and negatively correlated with the score of tension (P＜0. 05). The results of multifactor analysis showed that the sense of loss of control, employment relationship, and working for 1～10 years were the independent influencing factors of work engagement (P＜0. 05). Conclusion There are several factors affecting the work engagement of neurology nurses. As clinical nursing managers, they can adopt effective scientific management methods and take effective measures to relieve the psychological pressure of nurses, reduce the level of rumination thinking, and positively guide the establishment of positive emergency psychology, so as to improve the degree of nurses' work engagement, and ultimately achieve the goal of improving nursing quality and patient satisfaction. (目的 分析神经科护士工作投入现状及其影响因素。方法 采用便利抽样的方法, 于2022年4月—5月对北京某三级甲等综合医院神经科护士进行横断面调查。采用自行设计的一般资料调查问卷、工作投入量表、中文版知觉压力量表, 对神经科护士进行调查问卷。结果 本研究共发放问卷660份, 回收630份, 回收率95. 45%; 有效问卷630份, 有效率100. 00%。630名神经科护士工作投入得分为(35. 15±5. 34)分, 各个维度的平均分对比, 差异有统计学意义(P

Pinglu Canal is the backbone project of the New Western Land-Sea Corridor of China. The canal project generated a total of 3.39 × 108 m3 of earthwork that covers approximately 23 types of rocks and soil and is characterized by large amount, diverse composition, and scattered distribution. Currently, the earthwork is utilized mainly through landfill and reclamation (over 50%); however, basic problems exist, including a low high-quality utilization rate, lagging research on demand for earthwork-reused products, lack of innovative technologies for earthwork reuse, a low level of digitalization, and lack of carbon emission evaluation. To address these problems, this study proposes innovative solutions from the perspectives of resource utilization, digitization, and carbon reduction. First, it is necessary to explore the potential application demands for the canal project itself and surrounding areas and propose corresponding utilization paths according to different types of rock and soil, thus to achieve multi-scenario, multi-path utilization. Second, geological information models and information databases should be established for earthwork in excavation areas to help develop a digital excavation‒transportation‒storage‒utilization technology for earthwork. Moreover, it is recommended to conduct a lifecycle assessment to clarify the carbon emissions of multi-path utilization technologies, achieve a dynamic evaluation of carbon emissions by combining with the information from the earthwork databases, and develop modular mobile-type disposal equipment and in-situ utilization technologies to achieve the reduction of cost and carbon emissions. The organic combination of resource utilization, digitization, and carbon reduction is expected to provide a favorable support for the green construction of the Pinglu Canal Project.

The offshore completion fluid has the characteristics of complex composition and high salinity. In order to solve the severe corrosion of underground pipelines causing by completion fluid. In this paper，a polyamide chitosan（PACS） was synthesized from the natural polysaccharide chitosan，and its corrosion inhibition performance on carbon steel was investigated. The results of weight loss corrosion experiments showed that after adding 2 000 mg/L polyamide chitosan to the completion fluid at 80 ℃，the corrosion rate of carbon steel decreased from 3.852 to 0.072 mm/a，and the corrosion inhibition percentage was 98.13%. In addition，electrochemical tests（potentiodynamic polarization and Nyquist curve） also showed that when the concentration of PACS reached 2 000 mg/L，the corrosion inhibition percentages was more than 90%. PACS shows good corrosion inhibition properties of carbon steel.

[Objective] Through the treatment of hydrophilic and hydrophobic by the conditioner, the influence of different interface characteristics of the conditioner on the soil water and salt transport law was explored, and the improvement mechanism of fly ash-based soil conditioner on saline-alkali land was revealed in order to provide scientific reference for the improvement of different types of saline-alkali land in irrigation area of the Yellow River. [Methods] Taking sodic sline soil in Ningxi Hui Autonomous Region as a case study, the spatial transport patterns of different salt ions in the soil before and after modification with the soil conditioners were investigated by soil column experiments. [Results] After the addition of unmodified conditioner, hydrophilic-modified conditioner, and hydrophobic-modified conditioner, the surface desalination rates were 79.72%, 59.91%, and 84.79%, respectively, for a sodic saline soil far greater than the values obtained without conditioner added (12.64%). Compared with the unmodified conditioner treatment group, the water content of the hydrophilic treatment group was 6.59% greater, and the total salt amount was 47.13% greater. The water content of the hydrophobic treatment group was 0.67% less, and the total salt amount was 25.22% less. The pH values were reduced from 10.5 to 8.08 and 8.71, respectively. The surface Na+ contents were reduced by 10.39% and 30.46%, and the K+ contents were reduced by 10.22% and 45.93%, respectively. [Conclusion] The interface properties of soil conditioners significantly affected water and salt transport in the soil. The hydrophobic conditioner treatment was more effective in improving saline land, and increasing the infiltration of salts with soil water is more important for saline land improvement.

Objective To preliminarily summarize the epidemiological and clinical characteristics of functional movement disorder (FMD) based on movement disorders clinic in China. Methods and Results A total of 593 patients with movement disorders newly diagnosed in movement disorders clinic of 22 clinical medical centers from August to September in 2023 were included, including 37 patients (6.24%) with FMD and 556 patients (93.76%) with organic movement disorder. Comparison of the epidemiological characteristics of the 2 groups, the proportions of corona virus disease (COVID⁃19) infection (χ2 = 4.217, P = 0.040) and psychopsychological symptoms (χ2 = 18.694, P = 0.000) in the FMD group were higher than those in the organic movement disorder group, while age (t = 3.757, P = 0.000), age of onset (t = 3.720, P = 0.000) and proportion of hypertension (χ2 = 4.736, P = 0.030) were lower than those in the organic movement disorder group. Comparison of the clinical characteristics of the 2 groups, the FMD group had higher proportions of tremor (χ2 = 3.955, P = 0.047) and myoclonus (Fisher′s exact probability: P = 0.011) than the organic movement disorder group, and the proportions of parkinsonism (χ2 = 8.491, P = 0.004) and gait disorder (χ2 = 5.028, P = 0.025) were lower than those in the organic movement disorder group. Conclusions The age and age of onset, as well as the proportions of COVID⁃19 infection, hypertension, psychopsychological symptoms, tremor, myoclonus, parkinsonism and gait disorder with FMD were different from those with organic movement disorder in China.

ObjectiveThis study aimed to provide basic data for the formulation of laws and regulations related to prebiotic health food and product production， by systematically investigating the product information of prebiotic health food approved in China.MethodsThe examination and approval information of health food containing prebiotics in China from 1996 to 2022 were investigated， including the ingredient list of health food， functional claims， and suitable population information. The product information database was established. The frequency of adding prebiotic ingredients， product functional claims， and suitable population distribution were statistically analyzed.ResultsA total of 504 prebiotic health foods were approved from 1996 to 2022. Prebiotics were mostly added in the form of combination， but the ingredients used were mainly concentrated in three kinds， which were fructo-oligosaccharides （44.44%）， isomalto-oligosaccharide （22.02%）， and xylo-oligosaccharides （19.05%）. The function was claimed to be relatively simple. The products of “enhancing immunity”， “defecating”， and “regulating intestinal flora” account for 38.20%， 32.60%， and 14.60%， respectively. The common suitable people in the product were those with low immunity， constipation， and gastrointestinal dysfunction.ConclusionHealth food containing prebiotics in China has a favorable development space in the future. Updating the relevant policies and regulations， guiding the production enterprises to follow up in time， and promoting a healthy development of health food containing prebiotics in China is necessary.

In this study, we investigated the effect of toughening treatment (55 ℃ for 0, 12, 24, 36, 48 and 60 h) on the microstructure, pasting properties, thermal properties, rheological properties and 3D printability of potato starch. The results showed that the toughening treatment roughened the surface of starch granules and increased the viscosity and pasting temperature of the starch. The toughened potato starch gel showed greater mechanical strength and a more stable and ordered internal structure than the native starch gel. It was found that toughening treatment for 36 h had a significant effect on the printing characteristics of potato starch gels, resulting in the highest printing accuracy and height as well as the best printing performance.

Objective To screen, identify and verify the immunoreactive epitopes on Hantaan virus glycoprotein C-terminal (HTNV Gc). Methods On the basis of predicting the major histocompatibility complex (MHC) gene in more than 98% of the global population, the affinity of 9-peptide and 15-peptide epitopes on HTNV Gc was systematically analyzed by bioinformatics cutting-edge algorithms such as Immune Epitope Database (IEDB) and Technical University of Denmark (DTU). Their immunogenicity was analyzed by using the Vaxijen tool, and the interspecies intraspecific conservation was analyzed with the Blastp tool. Bidirectional hierarchical clustering was employed to compare the cross-immunoreactivity of MHC-class Ⅰ and class Ⅱ restricted epitopes. Possible results of dominant epitopes docking with MHC were simulated by using molecular docking. Enzyme-linked immunospot (ELISpot) assay was performed to validate the results of computer analyses. Results After integrating the results of various bioinformatics algorithms, we obtained 8 9-peptide epitopes and 80 15-peptide epitopes with high affinity, intraspecific conservation and strong immunogenicity, including 8 human-mouse common dominant epitopes. Cluster analysis showed that H-2 genotype had certain similarity as HLA genotype. The results of molecular docking revealed that dominant epitopes had good docking with various MHC genotypes, which were consistent with the results of affinity analysis. The amount of IFN-γ secreted from the spleen cells was higher in the mice with dominant epitopes than those with non-dominant epitopes. Conclusion With the aids of various bioinformatics algorithms, we successfully screen out the dominant epitopes on HTNV Gc, and validate the cellular immunoreactivity of these epitopes through ELISpot assay.

Ecological monitoring is an important part of environmental protection. To monitor the movement and abundance of animals in the airspace, an Aerial Ecological Monitoring System (AEMS) is developed by CMA Meteorological Observation Center for China's next-generation weather radar (CINRAD) network. Characteristics of weather radar clear air echo data and airborne biological scattering data are studied to identify biological echoes through fuzzy logic algorithm, and the system can monitor real-time ecological activities of insects such as biological density, migration path and space-time distribution.Weather Radar Airborne Ecological Monitoring System has been put into trial operation since May 2022. During the real-time monitoring period, it's found that the insect activity shows obvious spatial and temporal distribution characteristics. From August to September, pests are of large quantity and wide range, indicating urgent need of insect disaster prevention and control. In May, June, September, and October, insect activity gradually increases from 2000 BT every day, reaches its peak from 2200 BT to 2300 BT, gradually decreases thereafter, and disappears mostly by 0600 BT. In July and August, insect activity gradually increases from 2000 BT every day, with a peak from 2100 BT to 2200 BT. Insect activity begins during the daytime, increases at 0600 BT, becomes more frequent at 1300 BT, and gradually decreases thereafter. From May to July, there is a significant shift from south to north (i.e., northward migration process), and in late August, it quickly changes into a to southward migration. The southward migration process of insects is larger and more numerous than the northward migration process. It's verified that the system can effectively monitor real-time aerial ecology, providing technology and data support for precise pest control.However, characteristics of pests need further research and clear distribution of pests is an urgent need. Therefore, in-depth research will be carried out on aerial ecological classification technology, combined with other direct observation means such as real-time monitoring by drones to explore the relationship between radar detection and different pests, and improve the ability to identify different kinds of insects.

[Objective] The structure and sustainability of livelihood factors and their coupling coordination under different grazing intensities were studied in order to provide a scientific basis for optimizing the livelihood strategies of farming households, increasing their economic income, and realizing rural revitalization. [Methods] Taking the typical district of loess hilly area as an example, based on the sustainable livelihood framework, constructing the evaluation index system from multiple livelihood elements, combining the survey data of farmers and mathematical modeling, a comprehensive study was conducted on the sustainability of livelihoods of farmers with different grazing intensities and their coupled and coordinated development. [Results] ① Grazing intensity enhanced the sustainability of farmers’ livelihood capital, but there were significant differences in the effects on the sustainability of livelihood environment, livelihood strategies, and livelihood outcomes. ② Livelihood sustainability was highest under moderate grazing intensity, and livelihood capital, livelihood environment, livelihood strategy, and livelihood outcome sustainability increased by 37.86%, 3.83%, 9.92% and 30.45%, respectively, compared with non-grazing farmers. ③ The coupling coordination development characteristics followed the order of moderately grazing farmers > lightly grazing farmers > heavily grazing farmers > non-grazing farmers. Farmers’ livelihood coupling degree was higher than the coordination degree, indicating that the livelihood system of grazing farmers in the loess hilly region had a strong inter-role intensity, and that good coupling and synergistic development within the system had not yet formed. Therefore, it will still be necessary to further strengthen the transformation and upgrading of farmers’ livelihoods to improve their livelihood sustainability in the future. [Conclusion] Moderate grazing can increase livelihood capital and optimize livelihood strategy for farming households in the loess hilly region, and increase the livelihood sustainability and economic income of farming households.

Based on the structural characteristics of ring-shaped roller screw mechanism (RRSM), helical equations of the screw, roller and nut are derived. Meshing equations at the screw-roller and nut-roller interfaces are developed, which can be used to calculated contact positions of thread teeth. The equations of axial clearances in the RRSM are also derived and zero-clearance design values of the thread thicknesses are given. By comparing the contact positions and clearances obtained from a previously published numerical model, the feasibility of the proposed model is validated. The influence of structural parameters on the meshing characteristics of the RRSM is analyzed. When the nominal radius of the screw is increased or that of the roller is decreased, the contact point at the screw-roller interface will move towards to the tangential-point of pitch circles. The difference between the value of the screw flank angle and that of the screw flank angle has great influence on contact positions. When the values of the nut and roller flank angles are equal, the contact points will lie on the tangential-point of pitch circles and the zero-clearance design value of the thread thickness at the nut-roller interface is equal to the half of the screw pitch. The radius of the roller thread profile has little influence on the zero-clearance design values of thread thickness.

Aiming at the problem that the fatigue performance of aeroengine blade leading edge was seriously degraded after foreign object damage（FOD）, the surface of TC4 titanium alloy thin wall specimen was treated by laser shock/mechanical shot peening, and the residual stress gradient distribution on the specimen surface before and after the composite strengthening was measured by X-ray diffraction method； The high order vibration fatigue life of TC4 titanium alloy thin wall specimens before and after treatment was tested by electromagnetic vibration table, and FOD was introduced into the specimen surface by fabricating pits of different shapes with a hardness tester； The fatigue fracture surface was analyzed by SEM； The evolution of residual stress distribution on the specimen surface before and after FOD was simulated by finite element dynamic numerical simulation, and the mechanism of the influence of the composite strengthening layer on the notch fatigue performance of FOD was revealed. The results show that the average fatigue life of the composite strengthened FOD specimen is 370% and 60% higher than that of the non strengthened FOD specimen and the non strengthened FOD specimen, respectively. The deep residual compressive stress field（thickness 500 μm）formed on the surface layer of the specimen after composite strengthening is an important reason for increasing the fatigue life of FOD specimen.

Aiming at the abnormal vibration phenomenon of low-pressure cylinder during the debugging period of a new 660 MW ultra-supercritical steam turbine unit， through vibration test and analysis， it is concluded that the bearing bush of low-pressure cylinder has low dynamic stiffness and its resonance frequency is close to the working speed， if the shaft vibration climbs due to factors such as dynamic and static rubbing， the tile vibration will be caused to climb significantly. At the same time， it is found that the gap between the low-pressure outer cylinder and the cosmetic plate is too small， which will induce the generation of low-frequency structural resonance. During the operation of the unit， measures are taken to adjust the steam supply temperature of the low-pressure shaft seal and control the load of the unit. During the maintenance， measures such as adjusting the clearance of the cosmetic plate of low-pressure cylinder， the installation size of the bearing， and the fine dynamic balance are adopted to reduce the abnormal vibration of the low-pressure cylinder， which improves the stability of the low-pressure cylinder and ensures the safe and reliable operation of the units.

ObjectiveStatistical analysis of the domestic health food that has been filed from July 2017 to April 2022 was carried out to provide reference about the research and filing of health food for manufacturers ， and to provide data support for regulatory authorities to formulate relevant regulations.MethodsA total of 9 835 health food records were collected from the special food information inquiry platform of the State Administration for Market Regulation and administration for market regulation of all provinces， autonomous regions and municipalities directly under the Central Government. The number of records， filing regions， dosage forms， product types， health functions and raw material compatibility were analyzed.ResultsThe number of health food records in China had been increasing overall since 2017， but the regional distribution of health food records was uneven. Among them， tablets accounted for more than 50% and capsule products for about 30% in shape； of 8 950 nutrient supplements， the largest number of products supplemented with single nutrient supplements was 43.7%. A total of 885 functional health food products had been recorded. The number of products with spirulina as raw material was less， while the number of other four raw materials were all over 150.ConclusionSince the beginning of domestic health food recording， the number of recorded products has reached up to nearly 10 000. We recommend that he relevant regulatory departments should continuously improve the existing regulations to ensure the steady and rapid development of health food filing in China. Manufacturers shall， in accordance with people’s health needs and relevant regulations， carry out formulation research and product filing， which will not only bring economic benefits to manufacturers themselves， but also help promote the construction of “Healthy China”.

In order to study the dynamic characteristics of flap transmission mechanism with clearance joints, based on an improved nonlinear normal impact force model with variable stiffness, and the elastic factor of connecting rod, the angular velocity and angular acceleration of the steering gear are simulated and analyzed with the conditions of different clearance joints （c=0、c=δ and c=1.6δ） , and different friction parameters （0.06、0.08 and 0.1）. The dynamic output angular velocity and angular acceleration of the flap transmission exhibit obvious oscillation, and the amplitude of the angular acceleration is larger than that of the angular velocity oscillation; at the same time, when the driving load changes, the angular velocity and angular acceleration fluctuate greatly, but the fluctuation degree in the case of c=0 is greater than that with clearance; in addition, the higher the friction coefficient at the clearance joint is, the greater the amplitude of angular velocity and angular acceleration oscillation are, accompanied by high-frequency oscillation and delay phenomenon.

In recent years, skin tissue engineering technology has provided new treatment ideas for large-area wound repair. Skin tissue regeneration is mainly based on the use of appropriate tissue scaffolds. There are several types of scaffolds, such as porous, fibrous, microsphere, hydrogel, and acellular scaffolds. Scaffold materials include natural materials and synthetic materials, but either type of single material has its own limitations. At present, most scaffolds are composed of two or more materials to form composites. Therefore an important direction of skin tissue engineering research in the future involves deeply understanding the properties, advantages and disadvantages of the various biomaterials and scaffolds currently used and exploring the construction of biomaterials and scaffolds with better performance. This article reviews the research progress and application value of different tissue scaffolds and scaffold materials in skin tissue engineering, in order to provide reference for clinical application and research and development in the field of wound repair.

The construction of a new electric power system is the key path to achieve the carbon peaking and carbon neutrality goals and ensure energy transition security. As the largest man-made system that is complex and highly nonlinear, the electric power system is the core of future energy transition. However, the security of the electric power system faces severe challenges owing to the volatility and randomness of new energy power generation. Considering the new situation and challenges faced by the energy transition security in China, this study clarifies the implications of energy security in terms of supply, environment, economy, and technology, investigates the development goals and strategic paths for energy transformation, and explores the significance of the new electric power system to energy security. The key factors of power source, power grid, load, energy storage, market, and technology that affect the new electric power system security are analyzed. According to the study, the core systems required for the security development of the new electric power system should be constructed from three aspects: emergency warning, sharing and mutual aid, and security defense. Furthermore, the basic idea for the research on the new electric power system development path is proposed to provide a basic reference for the new electric power system construction and the security development research.

ObjectiveTo systematically investigate the health food containing probiotics approved by the government in China， and analyze the application of strains， function claims， recommended intake and distribution of applicable population， and provide reference for the management reform of probiotics products.MethodsThe information of health food containing probiotics approved by the government in China from 1996 to 2022 were collected and investigated， including the kinds of probiotics， function claims， recommended intake and the information of applicable populations.ResultsA total of 168 health foods containing probiotics were approved in China from 1996 to 2022， 82.14% and 77.98% of the products used Lactobacillus and Bifidobacterium respectively， 61.31% of the products used Lactobacillus acidophilus， but all products were not labeled with the level of strain. In terms of function claims， most products claimed “enhancing immunity”， “regulating intestinal flora” and “laxative”. The recommended intake of probiotics ranged from 0.12 to 3.63×1011 CFU/d. Claims such as “immunocompromised people”， “people with intestinal flora imbalance” and “people with constipation” were the most common applicable populations for consumption. 42.86% of the products did not labeled with “the unsuitable population”， and more than 69.79% of the products labeled with “the unsuitable population” targeted at infants and young children.ConclusionThere are some approved health food containing probiotics in China， none of which is clearly labeled to the strain level， which is not in line with the scientific definition of probiotics. The existing products are of a single function， product function claim depends on the results of high-quality population studies. The approval of products suitable for infants and young children should be scientific and prudent.

This paper summarized the integrated traditional Chinese and Western medicine nursing for a patient with acute myocardial infarction with chest pain as the chief complaint. The thrombolytic therapy was conducted after comprehensive evaluation of pain and indications for thrombolysis. Integrated traditional Chinese and Western medicine nursing techniques were carried out to relieve the symptoms of chest pain and improve the prognosis and quality of life of the patient during treatment. (本文总结1例以胸痛为主诉的急性心肌梗死患者的护理经验, 通过对患者的疼痛程度、溶栓指征进行评估, 及时开展溶栓治疗, 同时开展溶栓治疗各阶段的护理配合, 利用中西医结合护理技术, 缓解急性心肌梗死患者胸痛症状, 改善预后, 提升生活质量。)

This paper summarized the nursing management of the nasogastric enteral nutrition for a patient with endotracheal intubation for acute respiratory failure complicated with severe pneumonia. Nursing interventions such as endotracheal intubation, nursing of enteral nutrition and prevention of aspiration and other issues were carried out to control infection, improve the patient’s pneumonia situation and reduce the occurrence of complications. (本文总结1例急性呼吸衰竭气管插管合并重症肺炎患者鼻饲肠内营养液的护理干预措施, 主要从气管插管、肠内营养的护理以及预防误吸等方面进行干预, 旨在控制感染, 改善患者肺炎症状, 减少并发症的发生。)

In order to study the changes in the content, type of the refractory phases and grain size during homogenization of the 5083 aluminum alloy, material microstructure was characterized by metallographic microscope (OM), scanning electron microscope(SEM), energy dispersive spectrometer(EDS), differential scanning calorimetry (DSC) and X-ray diffractometer (XRD). The results show that the refractory phases in the cast 5083 aluminum alloy are composed of Al(FeMnCr) phases, Al(FeMnCr)Si phases and Mg2Si phases. The composition of the cast state alloy was verified by using phase diagram calculations, and the results are basically consistent with the experiment. As the temperature rises from 460 ℃ to 560 ℃, the electrical conductivity increases firstly and then decreases. This is related to the precipitation of dispersed phase and the dissolution of refractory phase in the structure. When the homogenization processing is 540 ℃/10 h and 560 ℃/10 h, the refractory phase is dominated by the needle-flake Al(FeMnCr) phases, Mg2Si phases is fully solubilized, the area fractions are 0.730% and 0.632%, respectively, and there is no over burned tissue at the same time, and there are obvious dispersed phase particles in the grain. Therefore, to dissolve part of the refractory phases in cast 5083 aluminum alloy, the homogenization temperature must be ≥540 ℃. Increasing homogenization temperature and prolonging homogenization time will increase grain size.When the homogenization temperature is less than 540 ℃, the insoluble phase changes have little effect on the grain growth, when the homogenization temperature is greater than 540 ℃, the average grain size begins to be greater than 140 μm, and the refractory phase is dissolved at the same time.

Lung cancer is considered as the leading cause of cancer-related mortality worldwide. Non-small cell lung cancer (NSCLC) accounts for about 85% of primary lung cancer. Owing to the improved utilization of medical technological level and the popularization of health examinations, the detection rate of early-stage NSCLC is gradually increasing. The main treatment modalities for early-stage NSCLC are surgical resection and adjuvant chemotherapy. Platinum-based chemotherapy is recommended as the standard postoperative adjuvant treatment for patients with completely resected stageⅡ-ⅢA NSCLC. However, adjuvant therapy remains a controversial option in stageⅠB NSCLC. This review focuses on postoperative adjuvant therapy such as adjuvant chemotherapy, targeted therapy, and immunotherapy for completely resected stageⅠB NSCLC. Moreover, the biomarkers and prognostic factors of high-risk patients are discussed.

This paper proposes a SoC chip clock scheme and designs two layout schemes. By analyzing the causes of electromagnetic interference and judging the simulation results of the isolation degree between signals, the risk of inter-signal interference in the layout scheme can be identified in advance, which will deteriorate the output analog signal quality of SoC chip. In this paper, the simulation results of the isolation degree between signals are used to guide the layout design, and the optimization layout method is given to improve the performance of the isolation degree between signals. The test results show that the simulation results of the two layout design schemes are consistent with the actual results, which verifies the accuracy and reference of the simulation results.

A two-degree-of-freedom collission vibration system model with nonlinear constraints and initial precompression is established. The hysteresis region and distribution of the system are studied by using the 4-order Runge-Kutta numerical algorithm and multi-parameter co-simulation method. The stability of the co-existing motions in the hysteresis region is analyzed by cell mapping method. Finally, the influence of the change of basic parameters on the hysteresis domain of the system is deeply studied. The results show that the stability of coexisting motion changes with the change of excitation frequency in hysteresis domain. The decrease of the elastic stiffness ratio will reduce the hysteretic frequency of the system.

A type of single-degree-of-freedom mechanical impact vibration system with dry friction and nonlinear constraints is studied. Through the fourth-order variable step Runge-Kutta numerical algorithm, the dynamics of the mechanical vibration system generated by the low-frequency excitation of the p/1 periodic motion are analyzed. The effect of system parameters on the dynamic characteristics of the vibration model is analyzed by the method of multi-parameter co-simulation, and the frequency hysteresis characteristics of Grazing bifurcation and Saddle-node in p/1 periodic motion are revealed. And the range of coexistence attractors. Finally, combined with the cell mapping method, the distribution of different attractors and attracting domains in the polymorphic coexistence area and their transition laws are studied. The research results show that the Grazing bifurcation with the decrease of the excitation frequency, the number of collisions of the p/1 periodic motion will gradually increase until the flutter motion occurs, and due to the irreversibility of adjacent periodic motion, changing different initial values in the hysteresis domain will result in different periodic motions coexisting.

In order to improve the design efficiency of high-speed train gear coupling and optimize the design structure, the CAD/CAE technology is used to carry out the integrated design. The CAD software is used to design and virtually assemble the drive device and a motion simulation analysis of the drive device is conducted, which produce the wheel set linear speed of the traction motor under the rated speed and the maximum speed. The CAE software is used to adjust the drum gear. The coupling is subjected to static strength analysis and safety check to ensure its safety in service; the results show that the linear wheel speed of the traction motor is 243.3 km/h at the rated speed and 349.1 km/h at the maximum speed, respectively, which satisfy high-speed operating conditions. The maximum stress of the drum-shaped gear coupling under balanced conditions and maximum angular displacement conditions are 391 MPa and 403 MPa respectively, which meet the requirements of safe operation. The above-mentioned coupling CAD/CAE integrated design method provides a reference for its optimization.