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ObjectivesIn order to improve the performance and lifetime of solid oxide fuel cell (SOFC) systems, the 100 kW SOFC system was taken as the research object. The continuous adjustment of the controller coefficients was explored through reinforcement learning to realize the best comprehensive performance, while ensuring the output voltage tracking performance.MethodsA mechanism-based SOFC output voltage system model was established, an improved nonlinear active disturbance rejection controller (NLADRC) was used to make the output voltage track the reference value well by controlling the input gas flow. Conventional single-channel controllers can only satisfy one objective at a time, and dual-channel controllers will increase system complexity, cost and risk of failure. An improved NLADRC controller based on the twin delayed deep deterministic policy gradient (TD3) was proposed to optimize the coefficients of nonlinear error feedback control law.ResultsThe designed controller can improve SOFC output voltage tracking performance without violating fuel utilization constraints.ConclusionsThe designed controller has the advantages of strong adaptability, high stability, and the ability to overcome uncertainty, providing theoretical reference for designing output voltage controllers in practical SOFC systems.

The boom link mechanism refers to the key mechanism used to connect the boom and the body, which has an important impact on the stability, safety and efficiency of the elevating jet fire truck. Through mathematical models and computer simulations, it is the current mainstream optimization direction to optimize the structure of the boom linkage mechanism and improve its strength and stability. The finite element analysis method was used to establish a mathematical model, and the optimization goal was to minimize the sum of the forces on the hydraulic cylinder, which was transformed into a mathematical programming problem. The initial value, which was obtained in the finite element analysis, was difficult to meet all the design requirements, so the research focus transformed into solving optimization problems, which need to gradually optimize through iterations. The fmincon function was used to realize the sequential quadratic programming (SQP) algorithm, which is one of the most effective methods to solve the constrained nonlinear optimization problems, for the optimal design. After several iterations of calculation and optimization design, the design scheme that met the work requirements was successfully obtained.

To investigate the effect of three-dimensional (3D) reconstruction-assisted cognitive fusion in targeted prostate biopsy.

Stabilizing the power flow distribution in distribution networks and determining the connection locations and capacities of distributed generation are crucial issues in optimizing the operation of distribution networks with distributed generation. This paper proposes an energy storage scheduling and optimization model based on deep reinforcement learning （deep RL） to match the relationship between distributed energy resource allocation and electricity load demand， thereby stabilizing power flow distribution in distribution networks with high penetration rates. Using line losses and voltage fluctuations as the loss functions， the paper proposes a decision-making model for placement and sizing of distributed generation based on multi-objective genetic algorithm. Testing is conducted on the IEEE 14-bus system， and the results indicate that the algorithm can effectively select the optimal connection locations and capacities for distributed generation， reducing overall line losses while ensuring voltage amplitude remains stable.

Diabetic ulcer (DU), one of the common and serious complications in patients with diabetes mellitus, often leads to infection, necrosis and amputation, and has a long and costly treatment period. Because of DU's unclear healing mechanism and the difficulty of delayed healing, its treatment and management have been a major challenge in clinical medicine. In recent years, the potential role of mitochondrial autophagy in DU has become a research hotspot with the in-depth study of mitochondrial autophagy mechanism. Previous studies have shown that mitochondrial autophagy is an important intracellular self-repair mechanism that plays a crucial role in maintaining cellular health and functional stability. During the development of DU, mitochondrial autophagy plays multiple roles in attenuating oxidative stress and inflammatory responses, maintaining mitochondrial functional homeostasis, influencing cell proliferation and repair capacity during DU healing, promoting DU healing, and enhancing antimicrobial capacity. In this paper, we illustrate the multiple roles played by mitochondrial autophagy in DU prevention and treatment, as well as the potential applications of mitochondrial autophagy in DU therapy. It is expected to provide a basis for the clinical application of mitochondrial autophagy in DU treatment, and provide more effective strategies and solutions for the treatment of DU.

C14H11ClO4S, monoclinic, P21/c (no. 14), a = 8.2472(13) Å, b = 22.431(4) Å, c = 7.9308(13) Å, β = 106.278(2)∘, V = 1,408.3(4) Å3, Z = 4, Rgt (F) = 0.0363, wRref (F 2) = 0.0996, T = 296(2) K.

The closed-cycle process will generate a large number of radioactive aerosols, and its high humidity, high acidity, and high radioactivity lead to rapid failure and high replacement frequency of glass fiber high-efficiency filters. In order to solve the above problems, hydrophobic modification of the traditional glass fiber filter material was proposed to improve its tolerance to severe conditions. The low surface energy modifier (polydimethylsiloxane) was used to realize the chemical hydrophobicity of filter material. The microstructure was constructed by introducing SiO2 nanoparticles to further improve hydrophobicity. The modification effect was analyzed by means of SEM, FTIR and contact angle measuring instrument, and the filtration performance of the modified filter material was further studied. The research results show that the modification can effectively improve the hydrophobicity of the glass fiber filter material and improve its moisture resistance. The static contact angle of the simply chemically modified filter material can reach 146°, and the modified filter material after the introduction of SiO2 nanoparticles exhibit an angle of more than 150°. When the mass fraction of polydimethylsiloxane and SiO2 nanoparticles is 2.0% and 0.5%, respectively, the corresponding filter material GF-PS-0.5 shows the best acid resistance, which is mainly due to the synergy of chemical hydrophobicity and microstructural hydrophobicity. The hydrophobicity of GF-PS-0.5 remains stable after a sufficient amount of γ-irradiation, indicating its good radiation resistance. The modified filter material maintains excellent filtration performance, and the filtration efficiency exceeds 99.99%. The modification process can improve the tolerance of the glass fiber filter material without influencing the filtration performance, showing a good application prospect.

Paraquat (PQ) is a frequently used herbicide with neurotoxic effects after acute or chronic exposure. Although in vitro evidence supports the PQ toxicity to dopamine cells, its in vivo effects (especially the chronic exposure) remain ambiguous. In this study, we investigated the effect of chronic PQ exposure on the blood–brain barrier (BBB) damage and the underlying mechanisms.

Objective: In order to explore the extraction method and antioxidant activity of crude polysaccharide from edible fungus resources of reed. Methods: The characteristic Agrocybe praecox of reed edible fungus of Dongting Lake District was used as raw material, the extraction rate of polysaccharide was used as the index, and the extraction was carried out by ultrasonic-assisted hot water alcohol precipitation method. After taking the liquid-material ratio, ultrasonic extraction time, ultrasonic extraction power, hot water extraction temperature, hot water extraction time as the factors to finish the single factor experiments. Then the experiments was optimized by Box-Behnken center combined experimental design for the crude polysaccharide extraction process of Agrocybe praecox. The scavenging abilities of the crude polysaccharide on DPPH· free radical and ABTS+· free radical were also studied. Results: The results showed that the optimal extraction conditions were determined: the ratio of solid to liquid of 1∶50 (g/mL), ultrasonic extraction time of 20 min, eextraction power of 150 W, Hot water extraction temperature of 80 ℃, extraction time of 4 h. Under the conditions, the extraction rate of crude polysaccharide was 5.08%. The scavenging rates of DPPH· and ABTS+· were 55.05% and 58.47%, respectively. The semi-inhibitory concentrations of IC50 were 1.03 and 0.28 mg/mL, respectively. Conclusion: Under the optimal process parameters of ultrasonic-assisted hot water extraction, the extraction rate of polysaccharide is high, and the crude polysaccharide has a certain antioxidant activity in vitro.

The ultra-stable optical reference cavity (USORC) is a key element for a variety of applications. In this work, based on the orthogonal experimental design method, we study the vibration sensitivity optimization of a classical USORC with a 100 mm length. According to a test of 4 levels and 3 factors, the L 16 (43) orthogonal table is established to design orthogonal experiments. The vibration sensitivities under different parameters are simulated and analyzed. The vibration sensitivities in three directions of the USORC are used as three single-object values, and the normalized sum of the three vibration sensitivities is selected as comprehensive object values. Through the range analysis of the object values, the influence degrees of the parameters on the three single objects and the comprehensive object are determined. The optimal parameter combination schemes are obtained by using the comprehensive balance method and the comprehensive evaluation method, respectively. Based on the corresponding fractional frequency stability of ultra-stable lasers, the final optimal parameter combination scheme A1B3C3 is determined and verified. This work is the first to use an orthogonal experimental design method to optimize vibration sensitivities, providing an approach to vibration sensitivities optimization and is also beneficial for the vibration sensitivity design of a transportable USORC.

High-sulfur petroleum coke (PC) as solid waste has high treatment cost. Gasification technology can utilize PC and lignite for co-gasification. Organically combining the two is the key to expanding the adaptability of gasification raw materials. This work used thermal analysis technology to study the gasification reaction of PC and lignite systems in a CO2 atmosphere. The results show that the starting and end temperatures of the co-gasification of lignite/high-sulfur PC are lower than those of pure coke. The improved carbonization rate and gasification reaction index indicate that lignite improves the gasification performance. The gasification synergy factors are all greater than 1, indicating that the co-gasification process produces obvious synergism, and the synergism is more obvious in the gasification stage after 800°C. The lignite ash is gradually enriched on the surface of high-sulfur PC with the temperature increase, and the Ca and Fe elements have an obvious catalytic effect, but the catalytic effect has a saturation value. Ashes from lignite used as a multi-component gasification catalyst can increase the overall reactivity in the lignite/high-sulfur PC system, which can broaden the selection of gasification raw materials, and make efficient use of the resource characteristics of both.

A research program based on collaboration and cooperative control of construction robots is important for the development of the construction industry. This paper aims to develop and design a program based on collaborative construction robots and cooperative control technology to improve construction productivity. We construct a task planning and execution system for construction robots under distributed architecture, design the structure of the information management module, incorporate a hybrid network topology combining star and ring, improve the BEB algorithm to solve the channel collision problem, and form a multi-robot cooperative communication network system. Establish a multi-robot coordination model based on task division, adopt the idea of two-level division, propose a hierarchical distributed coordination method, and establish a hierarchical distributed coordination system framework. Use linearly varying inertia weights and acceleration factors to balance the global exploration and local search abilities of particles to form an intelligent path planning algorithm for construction robots. The simulation experiment environment is chosen, and each algorithm’s performance is analyzed. The simulation experiments involving collaboration and cooperative control of construction robots demonstrate the efficiency and practical application value of the optimization scheme designed and proposed in this paper.

This paper builds a spatial design model based on the reconstruction of 3D visual spatial points in an indoor environment and combines the minimum Euclidean distance to calculate the vector relationship between spatial points and realize the corresponding spatial point matching. For the exploration of traditional elements in spatial design, an extraction method based on the improved cuckoo algorithm is proposed. By adding a dynamic inertia weight adjustment method, one inertia weight value is randomly selected from the Gaussian distribution each time to balance the algorithm’s local and global search. By extracting traditional elements, calligraphy is the most frequent in the home space, with 79.4% integration. The tea set is the most frequent traditional element in the dining space, with 84.53% integration. A couplet is the most frequent traditional element in the public open space, with 71.98% integration. The extraction based on intelligent algorithms can help designers better integrate traditional elements in the design of environmental spaces.

The mine power grid operating environment is poor. When a short circuit fault occurs in the underground power supply system, the use of complex anti-skip trip protection device will reduce the reliability of the entire power grid and increase the cost. The mine power grid needs to ensure that the current quick-break protection can act instantaneously to remove the short circuit fault, especially at the line outlet. The current mine power grid protection scheme of the anti-skip trip can not take into account the protection quick-action, power supply reliability and equipment economy. In order to solve the above problems, according to the minimum principle that short-circuit accident in the mine power grid can not skip to the ground, a setting strategy of instantaneous current quick-breaking protection for mine power grid based on the overall optimal principle is proposed. The relationship between the short-circuit current value and the location of short-circuit point and the distribution characteristics of short-circuit current at the beginning and end of the line are analyzed. The shortcomings of the traditional single-setting method are compared and studied. Three indexes are defined, which are minimum-maximum system impedance ratio, maximum system impedance and line impedance ratio, and adjacent line impedance ratio. The indexes are used to represent characteristic relational expressions of different short-circuit current distribution scenarios and conditions for each setting method to meet the requirements. The setting methods applicable to instantaneous current quick-breaking protection under different short-circuit current distribution scenarios are determined. The corresponding optimal setting strategy flow is proposed. Taking a typical mine power supply line as an example, according to the proposed setting strategy, the setting calculation of the protection switch at all levels is carried out. The results show that the setting strategy is used to set five protection switches with the risk of the skip trip in the mine power grid model. The protection range of four protection switches can be controlled within the two-level line. The times of skip trip accidents are reduced. The probability of underground short-circuit faults extending to the surface of the mine power grid is reduced.

Objective: This study aimed to compare the efficiency of these two combined surgeries [prolapse and hemorrhoids (PPH) combined with the external hemorrhoidectomy and inferior internal hemorrhoid ligation; tissue selecting technique with mega-window stapler (TST-MS) combined with anal canal epithelial preservation operation]. Methods: This is a single-center, evaluator-blinded randomized controlled trial (RCT). A total of 204 participants were randomly divided into the two groups. The anal function, reoccurrence, intraoperative variables, and operative complications were assessed. The measurement data were compared by paired t test and rank sum test. Chi-squared or Fisher's exact test was used for count data and rank sum test for ranked data. To assess differences within each group in different time points, the repeated-measures analysis of variance was conducted. Results: TST-MS combined with anal canal epithelial preservation operation had lower Wexner score of anal incontinence (Z = 3.062, P = 0.002), higher patients’ satisfaction degree (t = 7.32, P 0.05). Conclusions: TST-MS combined with anal canal epithelial preservation operation showed better clinical efficiency in the treatment of prolapsed hemorrhoids. Trial registration: This study has been registered in Chinese Clinical Trial Registry (ChiCTR2000038533)

Solitary pulmonary nodules (SPNs) are one of the most common chest computed tomography (CT) abnormalities clinically. We aimed to investigate the value of non-contrast enhanced CT (NECT), contrast enhanced CT (CECT), CT perfusion imaging (CTPI), and dual- energy CT (DECT) used for differentiating benign and malignant SPNs with a multi-institutional and prospective study.

Aiming at the problem that Sparrow Search Algorithm(SSA) may fall into local optima and have slow convergence speed, a hybrid strategy improved sparrow search algorithm(HSISSA) is proposed in this paper, and it is applied to feature selection and model optimization of intrusion detection. First, a hybrid circle-piecewise map is proposed to initialize the population and improve the uniformity of the initial population distribution; second, merging the spiral search method in the vulture search algorithm and Levy’s flight formula to update the positions of the discoverer and scouter, respectively, to expand the population search range and enhance the search capability; and finally, the simplex method and pinhole imaging method are used to optimize the position of sparrows with poor fitness and optimal fitness, to avoid stagnation in the population search and fall into local optima. The performance of the algorithm was optimized using the aforementioned methods. The algorithm was tested on 10 classical benchmark functions and combined with Wilcoxon rank-sum test analysis to verify its effectiveness, which showed improvements in convergence speed and accuracy. Finally, it was applied to the feature selection and model optimization of intrusion detection. On average, 7.6 features and 10.1 features were retained on the CIC-IDS2017 and UNSW-NB15 datasets, respectively, and 99.5% and 96.01% accuracies were achieved. The number and accuracy of the optimized features were better than those of the original algorithm. For the DenseNet and random forest models, HSISSA achieved 99.34% and 97.22% accuracy after optimization, respectively, which improved the performance of the models. Thus, the algorithm showed a better performance than the other algorithms.

The complex and changeable working conditions of mechanical equipment in industrial field lead to uneven distribution of fault samples, which brings great trouble to traditional machine learning. In order to solve this problem, proposes a bearing fault transfer diagnosis method based on domain adaptive neural network and balanced dynamic distribution adaptive. Firstly, According to the characteristics of bearing vibration fault samples, the convolution layer of convolutional neural network is improved by wavelet transform, and the characteristics of bearing samples are extracted adaptively. Then, Maximum Mean Discrepancy measure and weight regularization are used to process the generated features in the loss function to reduce the difference in sample distribution and obtain the domain adaptive neural network model. Finally, A-distance is used to improve the equilibrium distribution adaptive to make it have dynamic characteristics, further improve the difference of sample distribution, and realize bearing transfer diagnosis by KNN classifier. Through experimental verification, the proposed method can accurately migrate the bearing fault state in the same bench rig cases and cross bench rig cases, proving that the method can effectively solve the problem of uneven distribution of unlabeled samples under variable working conditions, and has the effectiveness and robustness.

This study was conducted to investigate the effects of 60Co γ-radiation and electron-beam irradiation on the color of dried chili products through comparative analysis of the color difference, non-enzymatic browning index, color value, and R/Y value. The experiment included different doses (0, 3, 7, and 16 kGy) and different storage times (0 and 30 d). The results revealed that when no storage time elapsed (0 d), the a* value decreased by 13% in the dried chili samples treated with a 60Co γ-ray dose of 16 kGy; the non-enzymatic browning value increased by 12%, and the R/Y value decreased by 16%. Moreover, the a*, b*, and L* values of the samples treated with electron beams at 7 kGy were significantly lower than those treated with 60Co γ-rays. Furthermore, increasing the dosage of either the 60Co γ-rays or electron beam resulted in large color differences and small non-enzymatic browning values for the chili powder samples stored for 0 d. Notably, at a dose of 16 kGy, ΔE* of the chili powder treated with 60Co γ-rays was higher than that of the powder subjected to electron-beam treatment. By contrast, the non-enzymatic browning value of the 60Co γ-ray-treated sample was significantly lower than that of the electron-beam-treated sample. After 30 d of storage, ΔE* of the chili powder samples treated with a 7 kGy dose of either 60Co γ-rays or electron beam was significantly higher than that recorded for the other dosage groups. Further, ΔE* was the highest for the samples treated with a 7 kGy dose of 60Co γ-rays. In conclusion, the impact of electron beams on the color of the dried chili products was less than that of the 60Co γ-rays. Furthermore, the effect of irradiation on the color of the chili powder was stronger than that on the color of the dried chilis.

The loading and unloading elevators are the primary equipment in the refueling system, used for transferring fuel assemblies in the sodium-cooled fast reactors. The guideway friction pairs are the critical components of these elevators in the refueling system. With the excellent hardness and wear resistance in air, nitrided W18Cr4V steel is a promising material for the guideway friction pairs. In order to assess the feasibility of using nitrided W18Cr4V steel, it is essential to understand the aging behavior of nitrided W18Cr4V steel in high-temperature sodium. Aging tests were conducted on nitrided W18Cr4V steel in sodium and in argon environments at various temperatures for different exposure times. The results showed that the nitrogen atoms in the nitrided layer exhibited bidirectional diffusion behavior in the sodium or argon environment at 540 °C. Compared to the argon environment, cracks formed within the nitrided layer and the diffusion of nitrogen into the sodium was accelerated in the nitrided layer. As a significant number of nitrogen atoms had diffused into the sodium, there was little difference in the hardness between nitrided W18Cr4V steel and non-nitrided W18Cr4V steel after long-term exposure to 540 °C sodium.

BackgroundSmall rod-controlled pressurized water reactors have foregone the use of soluble boron and heavily rely on control rods and burnable poison rods for reactor control.PurposeThis study aims to explore the influence of control rods on the key performance metrics of a long-term small rod-controlled pressurized water reactor.MethodsFirst, a KLT-40 reactor used for nuclear icebreakers was taken as research object, and a critical rod position-search burnup code was developed based on OpenMC. Then, the core lifetime and other indicators such as the axial power offset, fuel utilization, and radial power peak factor, were compared between with and without the designed control rods for the design and analysis of the control rod layout of KLT-40 reactor. Finally, the influence of different move-in/out strategies on axial power offset was analyzed.ResultsThe core lifetime can be extended from 590 effective full power days (EFPDs) to 650~698 EFPDs with the designed control rods. Adopting a strategy of prioritizing the movement of low-value rod groups effectively reduces the axial power offset, with values of -0.69 and +0.8 decreasing to -0.29 and +0.52, respectively.ConclusionsThe control rod burnup calculation strategy adopted to accurately calculate the core lifetime of small rod-controlled pressurized water reactors can effectively reduce the axial power offset by using a reasonable move-in/out strategy.

The design and synthesis of porous framework materials with strong affinity and selectivity for uranyl ion are extremely appealing for the efficient extraction of uranium from seawater. Herein, rectangular porous framework cage(denoted as Co16) is prepared by using p-tert-butylsulfonylcalix［4］arene, CoCl2·6H2O and 1,3-bis(2H-tetrazol-5-yl)benzene (H2L) ligands under solvothermal conditions. Further, the Co16 is used for uranium extraction. As the result, the Co16 exhibits short adsorption equilibrium time(≈90 min) and is in accordance with the pseudo-second-order kinetic model. Robust framework and active U(Ⅵ) adsorption in the wide pH range are displayed. Besides, Co16 adsorbents exhibit high U(Ⅵ) uptake capacity(547.31 mg/g) and well fit the Langmuir model. Adsorption thermodynamics research has clearly demonstrated that the adsorption process is endothermic and spontaneous. Furthermore, Co16 achieves a high uranium adsorption capacity(4.88 mg/g) after immersing in real seawater for 20 days. Overall, these advantages of Co16 adsorbents highlight the potential candidate for the selective capture of U(Ⅵ) from seawater.

The space-air-ground integrated networks (SAGINs) are pivotal for modern communication and surveillance, with a growing number of connected devices. The proliferation of IoT devices within these networks introduces new risks due to potential erroneous synergistic interactions that could compromise system integrity and security. This paper addresses the challenges in coordination, synchronization, and security within SAGINs by introducing a novel static program analysis (SPA) technique using zero-knowledge (ZK) proofs. This approach ensures the detection of risky interactions without compromising sensitive source code, thus safeguarding intellectual property and privacy. The proposed method overcomes the incompatibility between SPA and ZK systems by developing an imperative programming language for SAGINs and a specialized abstract domain for interaction threats. The system translates network control algorithms into arithmetic circuits suitable for ZK analysis, maintaining high accuracy in detecting risks. Evaluations of real-world scenarios demonstrate the system’s efficacy in identifying risky interactions with minimal computational overhead. This research presents the first ZK-based SPA scheme for SAGINs, enhancing security and confidentiality in network analysis while adhering to privacy regulations.

In order to realize the rapid and non-destructive monitoring of wheat biomass, field wheat trials were conducted based on different densities, nitrogen fertilizers and varieties, and unmanned aerial vehicle (UAV) was used to obtain RGB images in the pre-wintering stage, jointing stage, booting stage and flowering stage of wheat. The color and texture feature indices of wheat were obtained using image processing, and wheat biomass was obtained by manual field sampling in the same period. Then the relationship between different color and texture feature indices and wheat biomass was analyzed to select the suitable feature index for wheat biomass estimation. The results showed that there was a high correlation between image color index and wheat biomass in different stages, the values of r were between 0.463 and 0.911 (P

[Objective] Land use change and its impacts on the ecological environment of the urban agglomeration of Chengdu Plain under the influence of rapid urbanization were analyzed and measured in order to provide a theoretical basis for optimizing land use structure and ecological environment management in the region. [Methods] Based on land use data from 2000 to 2019, the characteristics of land use changes in space and time for the urban agglomeration of Chengdu Plain were analyzed. The ecological effects of land use changes were then analyzed quantitatively in the region. [Results] ① The area of land use change in the urban agglomeration of Chengdu Plain from 2000 to 2019 showed typical characteristics of “four increases and two decreases”, of which the largest increase and decrease were construction land (an increase of 1 704.59 km2) and cultivated land (decrease 911.04 km2), respectively. In addition, the construction land and waters changed significantly over time. ② During 2000—2019, forest land had been the most important ecological land in the urban agglomeration, and its importance was as high as 53.81%, while the importance of the ecological value of construction land, water area, and unused land did not exceed 2%. In the state of urban expansion under the following conditions, changes in the four types of land use of cultivated land, forest land, construction land, and grassland had a greater impact on the ecology of the region, and the total ecological value contribution rate of changes in land use was 94.76%. ③ The ecological environment index of the urban agglomeration during the study period showed a pattern of decreasing first and then increasing. In general, the quality of the ecological environment in the region remained dynamic and stable, showing a relatively upward trend after 2015. [Conclusion] The government should control land use patterns, make intensive use of construction land, protect the quality and quantity of cultivated land, focus on implementing policies to protect forests and grasslands, and restore and improve the ecological environment of the urban agglomeration of Chengdu Plain, so as to enhance the sustainability of urban agglomeration development effectively.

Flux, able to improve the ash fusibility, usually contains catalytic metal compounds. Unfortunately, the quantitative analysis of synergistic catalysis effects between different fluxing agents on coal gasification has not been investigated thoroughly. In this study, the effect of the kinds and content of Na/Ca-based fluxes on char gasification was investigated in thermogravimetry analyzer (TGA). The synergistic catalysis effects and mechanism between the two kinds of fluxes were also studied. Finally, based on the TGA tests, the kinetics models for char gasification with flux addition were developed. The results showed that all the four Na-based fluxes could increase the char reactivity. Na2CO3, which afforded the best activity, could increase the reactivity by 5.3 times when the content was 5%. The five Ca-based fluxes had a weaker catalysis effect compared with Na-based fluxes. CaCl2, exhibiting the best activity among the five Ca-based fluxes, could increase the reactivity by 2.3 times when the content was 5%. For composite fluxes, Na2CO3–CaO and Na2CO3–CaCO3 had a remarkable synergistic effect, whereas others had less effect. Na2CO3 could inhibit the aggregation of Ca, which might cause the synergistic effects between Na and Ca fluxes. The random pore model was more suitable to describe the catalytic gasification process.

Rapid urbanization drives social development, but at the same time brings sustainable development Rapid urbanization drives social development, but at the same time brings sustainable development advantages of expanding underground space and relieving urban traffic congestion. High quality TOD complexes with natural elements in the intermediary space have been considered as one of the important means to address sustainable urban development. Nevertheless, intermediary spaces in TOD complexes face various challenges, such as significant contradictory factors in their physical environment spaces. This study classifies the underground open intermediary space into four types according to the characteristics of TOD complexes. And for these four types'Cthe physical environment—generated by various influencing factors of planar geometric, three-dimensional geometric, and detailed construction elements—is simulated using a numerical simulation method based on a static Taguchi experiment. The results demonstrate that space shape is a primary influencing factor for luminous and thermal environments; the window-atrium ratio (W/A ratio) and hole-atrium ratio (H/A ratio) comprise contradictory factors between the luminous and thermal environments of these spaces; profile inclination angle and sunken plaza height are primary impact factors for the acoustic environment; and skylight type has minimal influence on the physical environment. On average, their luminous and acoustic environment comfort can be improved by 200%; whereas, their thermal environment comfort can be improved by 21% and the potential for optimizing it in their shallow space (underground space depth ≤ 10 m) is relatively low. Subsequently, the necessity of comfort optimization as the passive optimization design of underground open intermediary spaces' physical environment in TOD complexes in the future is discussed. Finally, the feasible path and prospect of how to improve the livability and comfort of the spatial physical environment of TOD complexes are discussed and prospected.

Abstract Background To explore the correlation between the preoperative systemic immune inflammation index (SII) and the prognosis of patients with gastric carcinoma (GC). Methods The clinical data of 771 GC patients surgically treated in the Department of Gastrointestinal Surgery, Qinghai University Affiliated Hospital from June 2010 to June 2015 were retrospectively analyzed, and their preoperative SII was calculated. The optimal cut-off value of preoperative SII was determined using the receiver operating characteristic (ROC) curve, the confounding factors between the two groups were eliminated using the propensity score matching (PSM) method, and the correlation between preoperative SII and clinicopathological characteristics was assessed by chi-square test. Moreover, the overall survival was calculated using Kaplan-Meier method, the survival curve was plotted, and log-rank test was performed for the significance analysis between the curves. Univariate and multivariate analyses were also conducted using the Cox proportional hazards model. Results It was determined by the ROC curve that the optimal cut-off value of preoperative SII was 489.52, based on which 771 GC patients were divided into high SII (H-SII) group and low SII (L-SII) group, followed by PSM in the two groups. The results of Kaplan-Meier analysis showed that before and after PSM, the postoperative 1-, 3-, and 5-year survival rates in L-SII group were superior to those in H-SII group, and the overall survival rate had a statistically significant difference between the two groups (P < 0.05). Before PSM, preoperative SII [hazard ratio (HR) = 2.707, 95% confidence interval (CI) 2.074-3.533, P < 0.001] was an independent risk factor for the prognosis of GC patients. After 1:1 PSM, preoperative SII (HR = 2.669, 95%CI 1.881–3.788, P < 0.001) was still an independent risk factor for the prognosis of GC patients. Conclusions Preoperative SII is an independent risk factor for the prognosis of GC patients. The increase in preoperative SII in peripheral blood indicates a worse prognosis.

A novel ultrasonic vibration enhanced friction stir welding (UVeFSW) process was employed to join the 6061-T6 aluminum alloy and QP980 high-strength steel. The macro morphology, microstructure and tensile shear properties of the joint with or without ultrasonic energy were compared and analyzed. Meanwhile, the effects of ultrasonic energy on the welding load were studied. The results show that the ultrasonic vibration applied to the base metal before welding can soften the base metal, promote the plastic flow of the material, expand interface zone and nugget zone of the aluminum/steel, make more steel particles rotate into the aluminum alloy side with the stirring needle, forming a hook structure at the edge of the interface zone which can improve the failure load of the joint. The fracture position and fracture morphology of FSW joint are changed by ultrasonic, and the mechanical properties of FSW joint are improved. Under the welding parameters conducted in the experiment, the maximum average failure load of the joint is 4.99 kN. Under the conditions of a welding rate of 90 mm/min and a depth of 0.1 mm, the application of ultrasonic vibration makes the average failure load of the joint increase by 0.98 kN and the tensile shear performance increase by 28.24%. After applying ultrasonic vibration, the axial force Fz, the tool torque Mt and the spindle power decrease by 2.46%, 6.44% and 4.59% respectively.

Artificially tailoring the polarization and phase of light offers new applications in optical communication, optical tweezers, and laser processing. Valley topological physics provides a novel paradigm for controlling electromagnetic waves and encoding information. The proposed fiber has the inner and outer claddings possessing opposite valley topological phases but the same refractive indices, which breaks through the polarization constraints of the traditional fiber. Robust valley edge states exist at the domain walls between the inner and outer claddings because of bulk edge correspondence. The valley topological fiber modes exhibit the unprecedented radial and azimuthal polarization with high-order azimuthal index. Those topological modes are robust against the disorder of the fiber structure. These results enable guide and manipulate the optical polarization and angular momentum in fiber with high fidelity. The proposed fiber has the potential to become a powerful optical spanner for the application of bio-photonics.

Non-destructive stress characterization is essential for gate-all-around (GAA) nanosheet (NS) transistors technology, while it is a big challenge to be realized on nanometer-sized GAA devices by using traditional Micro-Raman spectroscopy due to its light spot far exceeding the device. In this work, a non-destructive stress characterization methodology of confocal Raman spectroscopy was proposed and performed for GAANS device fabrication. Channel stress evolution along the fabrication process was successfully characterized by designing high-density NS array and analyzing the linear scanned spectra in different structures. The related mechanism of stress evolution was systematically studied by Sentaurus process simulation. Additionally, applying this methodology on detecting the bending of suspended NS after channel release process was demonstrated. Therefore, this work might provide a promising solution to realize in-line characterization of channel stress in GAA NS transistors and process monitor of NS channel integrity.

Highly stretched and conductive hydrogels, especially synthetized from natural polymers, are beneficial for highly stretched electronic equipment which is applied in extreme environment. We designed and prepared robust and tough alginate hydrogels (GMA-SA-PAM) using the ingenious strategy of fully interpenetrating cross-linking, in which the glycidyl methacrylate (GMA) was used to modify sodium alginate (SA) and then copolymerized with acrylamide (AM) and methylenebisacrylamide (BIS) as cross-linkers. The complete cross-linked structures can averagely dissipate energy and the polymer structures can maintain hydrogels that are three-dimensional to greatly improve the mechanical performance of hydrogels. The GMA-SA-PAM hydrogels display ultra-stretchable (strain up to ∼407% of tensile strain) and highly compressible (∼57% of compression strain) properties. In addition, soaking the GMA-SA-PAM hydrogel in 5 wt% NaCl solution also endows the conductivity of the hydrogel (this hydrogel was named as GSP-Na) with excellent conductive properties (5.26 S m−1). The GSP-Na hydrogel with high stability, durability, as well as wide range extent sensor is also demonstrated by researching the electrochemical signals and showing the potential for applications in wearable and quickly responded electronics.

The structure change of typhoon eyewall has important influences on tropical cyclone (TC) intensity, and it brings great difficulties to TC intensity forecast. Compared to the TC with only one eyewall, the dynamic and physical processes controlling the intensity change of concentric eyewalls are much more complex. Strengthening the research on this type of typhoons is conducive to improve the understanding of the structure and intensity change of TC. Recently, the process of eyewall replacement cycle (ERC) is well understood, but the mechanism of concentric eyewalls maintenance (CEM) remains unclear. Therefore, it is necessary to use a variety of observation data, numerical model, and data assimilation methods to analyze real typhoons to further explore the mechanism of CEM.The evolution of concentric eyewalls in Typhoon Lekima in 2019 is analyzed with CIMSS microwave satellite images, Wenzhou Doppler radar in China and Ishigaki radar in Japan. Observational analysis indicates that secondary eyewall formation (SEF) happens at about 0600 UTC 8 August 2019. Unlike most concentric-eyewall typhoons, Typhoon Lekima has not undergone ERC, and the concentric eyewalls in Typhoon Lekima maintains for 35 hours.Meanwhile, a numerical experiment of Typhoon Lekima is performed using a WRF-based ensemble Kalman filtering (EnKF) data assimilation system. The evolution process of Typhoon Lekima is reproduced by the results of the analysis after assimilating the Ishigaki radar radial wind, and the simulated track, intensity, and structure are basically consistent with observational analysis. Therefore, based on the EnKF analysis fields, evolution characteristics of three-dimensional eyewalls structure in Typhoon Lekima are further analyzed. The results show that, in the initial stage of SEF, the inertial stability of the middle and lower layers of typhoon is high, and the thermal conditions of the environmental are conducive to the development of Typhoon Lekima. However, due to the strong vertical wind shear (VWS) and dry air intrusion in the mid-upper level, the outer eyewall has a weakening and asymmetric process. In addition, the maintenance mechanism of persistent concentric eyewalls is studied from the perspective of transverse circulation. The Sawyer-Eliassen diagnose is performed to investigate the transverse circulation and to reveal that the interference between the convection/subsidence couplet of the inner and outer eyewalls transverse circulation is not obvious so that the convection of the inner eyewall is not inhibited by the outer eyewall, and the inner eyewall maintains. Under the condition of strong VWS, the asymmetric outer eyewall cannot continuously enhance or contract and replace the inner eyewall, the structure of concentric eyewalls can be maintained for a long time. The structure of the outer eyewall and the distribution of transverse circulation in Typhoon Lekima play an important role in the maintenance of concentric eyewalls.

Four different types of silica particles (A200, H2000, R812S, T36-5) were used as reinforcing fillers for EPDM to prepare microcellar EPDM foams by supercritical CO2. The viscoelasticity, vulcanization and cell structure of different silica were tested and characterized by scanning electron microscope and rubber processing analyzer. The results show that the EPDM matrix has good rheological property with fumed silica (A200, H2000, R812S) as reinforcing filter, which is conducive to the formation of cell structure and the cell density is increased with the increase of the degree of crosslinking. The modulus and viscosity of the EPDM matrix with silica T36-5 matrix as the reinforcing filler by using precipitation method are too high, therefore the cell structure is formed only in narrow pre-vulcanization interval. Among them, the EPDM matrix with silica A200 as the reinforcing filler can obtain a high degree of cross-linking without losing good rheological properties, and A200 can provide better heterogeneous nucleation, and significantly improve cell density and reduce cell size.

To solve the multi-objective optimization problem of functionally graded plates with cutouts,a method integrating extended isogeometric analysis（ XIGA） and material distribution variation is proposed. For the mechanical calculation of functionally graded plates with cutouts,the third-order shear deformation theory is introduced,and the extended geometric analysis is adopted. To improve the numerical accuracy,the quadtree adaptive gauss integral is used in the hole boundary region.The B-spline function is used to replace the traditional functional grade material distribution function in the description of material properties. In the optimization process,the control points describing material distribution are taken as design variables to establish multi-objective optimization problems with the largest first natural frequency,the smallest plate mass and the largest buckling critical parameters. The NSGA-II algorithm is selected as the optimization algorithm. The effectiveness of the proposed algorithm is demonstrated by some examples in this paper.