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With the rapid improvement of equipment integration technology, multi-spectrum detectors are integrated into compact volumes and widely used for object detection. Confront with this challenge, it is essential to propose a strategy to design a single-layer metasurface with multi-spectrum responses in microwave and infrared ranges. In this work, we proposed a method of designing meta-atoms, which is capable of achieving functional electromagnetic response at microwave and infrared individually. As a demonstration, a metasurface with four different occupation ratios and coding permutation features is designed, fabricated, and tested. In the microwave band, the pixel meta-atom is designed to realize highly efficient cross-polarization conversion between 5.0 and 10.0 GHz, which shows the metasurface can behave as ultra-low Radar Cross Section (RCS) reflectors in the working band; In the infrared band, different occupation ratio of meta-atoms are designed to realize the infrared emissivity from 0.60 to 0.80 in 3–14 μm, which can be used to exhibit digital infrared camouflage pattern. This work promotes the ability to use single-layer design to achieve digital infrared camouflage and microwave RCS reduction simultaneously. The one-layer design is simple in geometry, simplified in process, low cost in economy, and large scale in fabrication, which can promote practical use in compatible microwave stealth and infrared camouflage.

Aiming at the deformation and fracture of shaft wall caused by freezing and thawing of topsoil and water pressure of aquifer in severe cold mining area, fiber bragg grating strain sensors are installed along the circumferential and longitudinal direction of shaft wall, the damage identification method of shaft wall structure is proposed, the real-time monitoring system of shaft wall deformation is established, and the deformation and failure threshold of concrete structure is determined through the compression test of concrete samples, and the real-time monitoring and early warning of shaft lining structure are realized. The monitoring results of the auxiliary shaft wall of Lingdong Coal Mine in severe cold mining area for nearly a year show that the shaft wall fiber bragg grating monitoring system can monitor in real time, has good stability, good coupling with concrete materials, and is easy to form a sensor monitoring network. The maximum circumferential strain and axial strain of shaft wall are both lower than the yield strength threshold of concrete, indicating that the shaft wall is in a stable stage at present.

As the most common dynamic disaster of coal rock in deep coal mining, rock burst seriously affects the safe and efficient mining of coal resources. Accurate and timely to predict the rock burst is the best way to control and prevent it. In order to study the precursory information characteristics of coal rock impact to establish an efficient and accurate dynamic prediction model. The triaxial compression test of coal bursting liability performed to get the acoustic emission characteristic parameters of coal failure process, meanwhile the monitoring values of microseismic parameters of typical impact mine face were selected and compared with the AE parameters obtained in the laboratory, then based on the similarity of them, the relationship between laboratory-scale and engineering-scale impact acoustic information representation had been built. It shows the “stepwise” increase of accumulated AE energy during coal sample compression and the “lack of earthquake” phenomenon before the occurrence of large energy seismic events have a good correlation, both of them could be used to revealed the energy breeding process of coal and rock mass. The same energy index has the same evolutionary trend for the occurrence of large energy events at different scales, and it can be used as an early warning index of rock burst risk after quantification. In addition, the static factors and stress dynamic factors affecting the occurrence of rock burst in working face are selected, and the dynamic weights are given respectively by combining the microseismic parameters obtained, which modified by using the Bayesian probability, then a static cooperative comprehensive evaluation and early warning model of rock burst is constructed. Furthermore, the model is used to evaluate and warn the danger of a mining face in Henan Province, and the results are better than those of the traditional evaluation model, which shows the engineering applicability and accuracy of the model.

In the process of plunge cylindrical grinding, it is difficult to directly measure the contact stiffness between the grinding wheel and the workpiece. In order to solve this problem, a simplified method for qualitatively determining the contact stiffness between the grinding wheel and the workpiece is proposed, and the grinding parameters are optimized. Based on the dynamic model of plunge cylindrical grinding process, the transfer function of grinding process is deduced, and the mathematical model of the time constant and contact stiffness is established. A simplified method for qualitative determination of grinding contact stiffness is proposed. Further, multiple tests are conducted by controlling the wheel feed speed and the workpiece speed. According to the experimental results, the variation of the system time constant and the grinding force with the grinding parameters are analyzed. The relationship model between the contact stiffness and the grinding parameters is established by regression analysis, and the optimal values of the wheel feed speed and the workpiece speed in the specific grinding process are determined under the condition of meeting the machining requirements.

Objective To investigate the therapeutic and protective effect of ambroxol hydrochloride on acute lung injury caused by aspiration of gastric juice in rats. Methods SD rats were randomly divided into control group, model group (constructed by trans-cricothyroid membrane puncture with pH≈2.3 rat gastric juice, 1.5 mL/kg) and ambroxol hydrochloride intervention group (30 mg/kg). After 24 hours of modeling, the drug was administered through caudal vein once a day for 3 days. HE staining was used to detect lung tissue, lung wet to dry weight ratio (W/D) value and arterial blood gas analysis to evaluate the degree of lung injury, ELISA was used to detect IL-6, IL-10, TNF-α and C-reactive protein (CRP) levels in serum. Results Compared with the control group, the alveolar structure showed atrophy, interstitial edema, and inflammatory cell exudation. Hyaline membrane was formed and W/D value increased, pH and arterial oxygen pressure (pO2) decreased, arterial carbon dioxide pressure (pCO2) increased, and serum inflammatory factors (IL-6, IL-10, TNF-α and CRP) increased (P＜0.05). Compared with the model group, the intervention reduced the pathological changes of lung tissue, W/D value decreased, pH and pO2 increased, pCO2 decreased, serum inflammatory factors (IL-6, IL-10, TNF-α and CRP) decreased(P＜0.05). Conclusions Ambroxol hydrochloride can effectively reduce the acute lung injury in rats caused by gastric juice aspiration and has good therapeutic and protective effects.

In solving the boundary conditions of a hydrostatic motorized spindle, there are some certain errors between the boundary conditions calculated by the traditional empirical formula and the actual conditions. In order to solve this problem, an optimization algorithm based on response surface is proposed in this paper, which is based on the idea of composite experimental design. The mathematical models of air gap heat transfer coefficient between stator and rotor, forced convection heat transfer coefficient of spindle inner hole and temperature are established, which is also called the mathematical model of temperature field. By using ANSYS Workbench simulation analysis software, load the optimized convective heat transfer coefficient into the simulation model to solve the temperature field of the hydrostatic motorized spindle to solve the temperature field of the hydrostatic motorized spindle. After selecting the sensor measuring points for temperature measurement, the results are compared with the simulation results. The results show that: the maximum error between the front bearing simulation temperature measurement point and the experimental temperature point is only 9.41%, and the maximum error between the rear bearing measurement point and the experimental temperature point is 3.09%. And it verifies the effectiveness and reliability of the method to improve the simulation accuracy of the hydrostatic motorized spindle.

【Background and Objective】 Carrying capacity of water resources is an important parameter to measure sustainability in regional water resources use, and objectively evaluating its variation and vulnerability can improve water resources management. The purpose of this paper is to evaluate the dynamic carrying capacity of regional water resource, identify and diagnose its vulnerability. 【Method】 Considering significance of the components of five-variable connection numbers and the difference in influence degree of the set on the system situation, and referring to the universal gravitation and damping, a five-variable gravitation subtraction set pair potential model based on the connection numbers was constructed. The model was then applied to evaluate the dynamic water resources carrying capacity in Sichuan and Heilongjiang provinces, and the results were compared with the existing five-variable subtractive set pair potential. 【Result】 Overall, the bearing capacity of water resources in Sichuan province has seen improvement good. Based on the impact of the subsystems, their evaluation index was ranked in the order of ecological environment > social economic> water resource. Subsystems that were persistently potential or partial against-potential are vulnerable, and vigilance over them is thus required. In general, water bearing capacity in Heilongjiang is good, in which “rain” “service industry” are potential of “water production capacity”, while “population density”, “primary industry” are inverse potential. The five-variable gravity subtraction set of potential discrimination system set pair potential value and situational and five-variable subtraction set pair potential calculation results are basically identical, and on the diagnosis, identify vulnerability subsystem and index is more sensitive and effective. 【Conclusion】 Analysis of water resources carrying capacity evaluation, five-variable gravity subtraction sets for system development and diagnosis, identify the potential vulnerability subsystem and the index of the rationality and applicability of the constructed gravity subtraction of set pair potential of five-variable more conform to the calculation results and the actual physical meaning, and simple calculation, strong explanatory. A new set-to-potential method is provided for analyzing dynamically and evaluating the multi-level set pair system.

Objective To explore the degree of radical surgery for patients with intermediate- and high-risk gastrointestinal stromal tumors (GIST) and to find the correlation between targeted drug therapy and survival prognosis, and then to summarize the clinical diagnosis and treatment experience. Methods A retrospective reciew of the complete pathological and follow-up data of intermediate and high risk GIST patients diagnosed by surgery and pathology in Shanxi Bethune Hospital from September 2012 to December 2019 was made, and the relevant factors that affect their prognosis. Results The patient's gender, age, tumor location, whether it was ruptured, the degree of radical surgery was summarized, targeted therapy, and the overall survival (OS) of 3 and 5 years were different(P＜0.05). The location of the primary tumor in GIST patients, whether the tumor was ruptured, the degree of radical surgery, and targeted therapy were independent prognostic factors that affected their 3-year and 5-year OS. There were differences in the prognosis of patients with different degrees of radical surgery, different risk grades, and whether to use targeted drug therapy(P＜0.05). Conclusions Complete surgical resection (R0) combined with targeted therapy is the main treatment to improve the prognosis of patients with intermediate- and high-risk GIST, but patients with intermediate-risk GIST who received targeted drug therapy after surgery are failed to significantly improve their overall survival.

【Background】 Practical problems in water science and engineering are diverse and complex, characterized by nonlinearity and multi-dimensions. Satisfactory solutions to them are not easy to obtain using traditional data analysis methods. The projection pursuit regression proposed in the 1960s can fill this gap and it has been developed and applied rapidly. Since its introduction to China in the 1980s, the projection pursuit method has seen a widespread applications because of its superiority in processing multi-dimensional data and flexibility in problem-oriented solving. 【Objective】 The objective of this paper is to review and summarize the evolution and application of the projection pursuit method in different disciplines in China since the 1980s, as well as the areas to which it has been mostly used. 【Method】 Our analysis was based on the literatures collected from the China National Knowledge Infrastructure database and considered four categories in the collection: temporal change, the disciplines, journals that published papers using this method, as well as some keywords representative of its applications. The data was then analyzed using the visualization analysis function of the bibliometrics provided by VOSviewer. 【Result】 Application and research of the projection pursuit method in China can be roughly divided into four stages: Introduction stage from 1984 to 1992; slow development stage from 1993 to 1999, rapid development stage from 2000 to 2010, and stable development after 2011. Its research and application are primarily in water conservancy engineering, environment science and engineering, and quantitative economy. Four of the top five journals that have published most projection pursuit papers are all water science journals, indicating that this method might be most suitable for solving water-related problems and are widely appreciated by the water science community. The areas that used the projection pursuit most included comprehensive evaluation, regression analysis, scheme selection and dynamic clustering. The results of clustering analysis showed that the research and application of the projection pursuit method in water-related problems are mainly in theoretical development, water quality evaluation, analyzing carrying capacity of water resource, water safety, and vulnerability of water resource systems. 【Conclusion】 The projection pursuit method has been widely used in China, especially in water science for evaluating water quality, water safety analysis, as well as bearing capacity of water resources. The method still has potential. In theoretical perspective, further work might focus on the fundamentals, improving the algorithms to determine the projection index function and the window width radius, as well as coupling it with other methods. In practical application, the method has potential applications in areas such as diagnosis identification, early warning, decision making, and evaluation of dynamic systems.

With the increasing development of the microwave absorption materials, nitride material has attracted more attentions, and is expected to become a new kind of potential microwave absorbing materials due to their excellent physical and chemical properties. In this paper, the research status of nitride microwave absorbing materials was discussed, and the research status of titanium nitride, iron nitride, manganese nitride, boron carbon nitride and alloy nitride was summarized in detail. Finally, the developing trend of nitride materials was prospected from the aspects of morphology control, bionic structure design, high temperature microwave absorption and microwave absorption mechanism.

Taking a low-speed two-stroke marine diesel engine bedplate as the research object.The main bearing seat（material ZG200-400） crack growth rate was tested,and the fatigue crack growth rate and the Paris formula of the stable expansion section were obtained.The three-dimensional crack propagation life analysis model of the main bearing seat was established by the sub-model method.The real boundary conditions of the main bearing seat was obtained by combining with the analysis results of the alternating stress of the bedplate under the actual operating conditions of the engine（360 degree crank angles）.The crack growth life of the main bearing seat with initial crack was calculated.The analysis results show that the crack growth life is less than that of the low-speed two-stroke marine diesel engine overhaul inspection interval.The research results of the thesis provide an reference for the damage tolerance in design engineering application.

The porous TiO2 powders were prepared by sol-gel method using titanium tetrachloride as titanium source, P123 as template agent and cyanamide as stabilizer agent, respectively. The porous TiN powders were synthesized via reduction and nitridation of the porous TiO2 powders at 900℃ in NH3. The phase composition and microstructure of the porous TiN powders were characterized by the XRD, SEM, BET, TEM and SAXD. The electrochemistry performance of the porous TiN powders was evaluated through the cyclic voltammetry, AC impedance and constant current charge-discharge techniques. The results show that the porous powders have approximate spherical particles with cubic TiN phase. Compared to the porous TiN powders without P123 adding, the mesopores with pore diameter range of 10-50nm increased in the porous TiN powders with P123 adding. There are also some pores with size range of 2-3nm. Meanwhile the porous TiN powders with P123 adding exhibit more ordered mesopores. This porous structure can improve the electrochemistry performance of the TiN powders. As a result, for the porous TiN powders without P123 adding, the specific capacitance is 81F·g-1. The internal resistance R1 is 1.1Ω, and the ion diffusion impedance W1 is 2.5Ω. For the porous TiN powders with P123 adding, the specific capacitance is increased to 95F·g-1, the R1 and W1 value are decreased to 0.9Ω and 0.06Ω, respectively.

Hyperbranched polymers (HBPs) are a new kind of polymers used as modifiers of epoxy resins to increase their strength and toughness without affecting the processability. The influence of some HBPs on the physical properties and thermal resistance of epoxy resin was summarized in this paper, including four parts:hyperbranched polyether as an epoxy modifier, hyperbranched polyamide/polyimide/polyethyleneimine as an epoxy modifier, hyperbranched polysiloxanes as an epoxy modifier and other hyperbranched polymers as an epoxy modifier. Then the drawback of hyperbranched polymers used as modifiers of epoxy resins was revealed. In addition, more and more fascinating materials and devices based on hyperbranched polymers will be successfully developed and fabricated in the future. The main limitation of the HBPs in the field of epoxy resin modification is that the synthesis steps of most HBPs are cumbersome. Thus, in the future, with the advent of simpler, greener synthetic methods, HBPs will be more widely used in other emerging fields and modified resins.

Polyhedral oligomeric silsesquioxanes (POSS) has a unique structure and good heat resistance. After the function- alization of POSS, a new type of organic-inorganic hybrid material with high performance can be obtained, which has potential application value in many fields. This paper reviews the related issues of the synthesis and functionalization of POSS. Many types of POSS are widely used, but the relatively expensive price limits the development scale of POSS in many fields. POSS can be used as the modifier of epoxy resin, which has obvious strengthening and toughening effects, and significantly improves the heat resistance of cured epoxy resin. However, due to the nanometer size effect of POSS, the addition amount of POSS in the resin is limited. In the future , with the cost reduction of POSS synthesis and the continuous improvement of the means to modify the resin, the application scope of POSS in the modification field of thermosetting resin will be expanded.

The formation and preservation of the active phase of the catalysts at the triple-phase interface during CO2 capture and reduction is essential for improving the conversion efficiency of CO2 electroreduction toward value-added chemicals and fuels under operational conditions. Designing such ideal catalysts that can mitigate parasitic hydrogen generation and prevent active phase degradation during the CO2 reduction reaction (CO2RR), however, remains a significant challenge. Herein, we developed an interfacial engineering strategy to build a new SnOx catalyst by invoking multiscale approaches. This catalyst features a hierarchically nanoporous structure coated with an organic F-monolayer that modifies the triple-phase interface in aqueous electrolytes, substantially reducing competing hydrogen generation (less than 5%) and enhancing CO2RR selectivity (∼90%). This rationally designed triple-phase interface overcomes the issue of limited CO2 solubility in aqueous electrolytes via proactive CO2 capture and reduction. Concurrently, we utilized pulsed square-wave potentials to dynamically recover the active phase for the CO2RR to regulate the production of C1 products such as formate and carbon monoxide (CO). This protocol ensures profoundly enhanced CO2RR selectivity (∼90%) compared with constant potential (∼70%) applied at -0.8 V (V vs RHE). We further achieved a mechanistic understanding of the CO2 capture and reduction processes under pulsed square-wave potentials via in situ Raman spectroscopy, thereby observing the potential-dependent intensity of Raman vibrational modes of the active phase and CO2RR intermediates. This work will inspire material design strategies by leveraging triple-phase interface engineering for emerging electrochemical processes, as technology moves toward electrification and decarbonization.

Advanced carbon fibers reinforced polymer-based composites have been widely used in the fields of aeronautics and aerospace, due to their excellent mechanical properties. However, their poor conductivity may cause severe lightning damage and electromagnetic interference issues of composite structures, which significantly restricts large-scale applications and overall performance of the composites. In this paper, a critical review was made on the recent research progress of electrically conductive composites which may be potentially used in aeronautics structures. The different methods of conductive modification for matrix resin, reinforcing fiber and laminated plate were introduced respectively. In particular, the representative studies using new carbon nanomaterials such as carbon nanotubes and graphene were discussed in details. The combination of matrix resin modification and laminated plate modification is expected to achieve a good match between mechanical properties and electrical conductivity of composites.

Steelmaking contributes 8% to the total CO2 emissions globally, primarily due to coal-based iron ore reduction. Clean hydrogen-based ironmaking has variable performance because the dominant gas-solid reduction mechanism is set by the defects and pores inside the mm- to nm-sized oxide particles that change significantly as the reaction progresses. While these governing dynamics are essential to establish continuous flow of iron and its ores through reactors, the direct link between agglomeration and chemistry is still contested due to missing measurements. In this work, we directly measure the connection between chemistry and agglomeration in the smallest iron oxides relevant to magnetite ores. Using synthesized spherical 10-nm magnetite particles reacting in H2, we resolve the formation and consumption of wüstite (Fe1-xO)-the step most commonly attributed to whiskering. Using X-ray diffraction, we resolve crystallographic anisotropy in the rate of the initial reaction. Complementary imaging demonstrated how the particles self-assemble, subsequently react, and grow into elongated whisker structures. Our insights into how morphologically uniform iron oxide particles react and agglomerate in H2 reduction enable future size-dependent models to effectively describe the multiscale aspects of iron ore reduction.