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Hypersonic vehicles as next-generation aircraft have broad applications, but existing technologies of onboard power generation are hardly applicable due to the change of engines. In this research, a catalytic steam reforming enhanced closed-Brayton-cycle power generation system based on is developed. This system combines the closed Brayton cycle (CBC) and catalytic steam reformed fuel vapor turbine (CSRFVT) to supply electric power. The zero-dimensional models of CBC and the CSRFVT are established to evaluate system performance. Results indicate the products with a water content of 30% have the strongest working ability, which can reach 330 kJ/kg. Moreover, the thermal efficiency and electric power of the parallel arrangement are higher than that of the series arrangement. Besides, the lower pressure of water is beneficial to the electric power. However, the difference in electric power between various pressures is less than 1 kW. In addition, under the same heat absorption, the total electric power of the system based on fuel and water is higher, and the former's outlet temperature of cooling channels is lower. The maximum total electric power of the novel system is about 120 kW. This research provides an innovative technical solution for the power generation of hypersonic vehicles. • A novel power generation system based on hydrocarbon fuel and water is proposed. • A zero-dimensional model of the system performance is established. • The products with a water content of 30% have the strongest working ability. • The maximum total electric power of this system is 120 kW at Ma 6. Abstract. [ABSTRACT FROM AUTHOR]

• Reliability of URTNs considering the traffic congestion diffusion is studied. • An improved NLC model under different attack strategies is proposed to simulate cascading failures. • A load redistribution method with the impedance function is provided. • Formation time, diffusion speed, and scale of cascading failures are analyzed. The cascading failures caused by traffic congestion diffusion may deteriorate traffic network reliability. Comprehending urban traffic congestion mechanisms is essential for road network planning and traffic management against cascading failures. To uncover this, the reliability of urban road traffic network (URTN) under cascading failure considering different attack strategies is analyzed. The cascading failure model is established based on the improved nonlinear load-capacity relationship. Five kinds of attack strategies including Strength Attack (SA), Betweenness Centrality Attack (BCA), Eigenvector Centrality Attack (ECA), Closeness Centrality Attack (CCA), and Random Attack (RA) are selected. In particular, the capacity affected by traffic congestion is considered, providing a new perspective for the study of traffic congestion diffusion. A state update equation for networks is proposed to simulate the network congestion diffusion. Finally, a case study is conducted by using the URTN of Shanghai as the background. The results show that the network will experience large-scale congestion when high-importance nodes are attacked. The congestion degree is the highest under CCA strategy, network efficiency is the lowest under ECA strategy, and traffic quality is the poorest under CCA strategy. As the congestion critical failure threshold decreases, the speed and scale of cascading failures caused by traffic congestion diffusion are greater. Maintaining proper traffic management and control capability can largely reduce the cascading effect to a great extent and improve the reliability of the network. The results can provide a research basis for traffic management to improve network reliability. [ABSTRACT FROM AUTHOR]

• Fast and batch of settling mud flocs measurement and 3D reconstruction. • Volumetric floc reconstruction improves the accuracy of irregular mud floc sizes. • Stable bimodal volumetric floc size distribution forms in equilibrium flocculation. • Settling velocity keeps stable and low variability between 1 and 2 mm·s−1 in >200 μm. • High Volumetric- but low Mass- Settling Flux in flocs>200 μm due to bio-components. Mud flocculation and settling play key role in understanding sediment transport cycle and affect water quality in estuaries and coastal seas. However, the morphological irregularity and structural instability of fragile mud flocs set huge obstacles for quantifying geometric property accurately and establishing reliable predicting tools in settling dynamics via previous observing strategies based on instant measured and 2-dimensional imagery floc parameterizations. Here we designed a multi-camera apparatus targeting capturing multiple angles of individual flocs, and developed a multi-view segmentation algorithm on floc images analysis. We finally accomplished batch of 3-dimensional reconstruction obtaining each settling floc's volumetric size in equilibrium flocculation. The results indicate a stable bimodal floc size distribution in equilibrium flocculation with a dominant peak of microflocs (<200 μm) and a secondary smaller peak of macroflocs (> 200 μm). The flocculi (<50 μm) shows more spherical outlines with dense structure while the larger-sized macroflocs (>200 μm) have high irregular morphologies with high porosity and visible biological debris attaching, and the microflocs (50–200 μm) tend to be irregular in shape and dense inside. The terminal settling velocity of mud flocs shows increasing with floc size in <200 μm but keeps stable around 1–2 mm s−1 after >200 μm due to the increase in size being compensated by the decrease of density according to the fractal theory on floc geometry. The higher organic matter content within larger porous flocs reduces the macroflocs effective density. These lead to high volumetric settling flux but low mass settling flux of macroflocs in natural water systems. This work provides new insight to reveal more accurate mud floc geometric parameterizations in volumetric aspect and reliable characterizations of equilibrium flocculation using a fast and sound batch of direct measuring approach. This may importantly improve the predictions of suspended mud dynamics in nature. [Display omitted] [ABSTRACT FROM AUTHOR]

The segmented cooling thermal management system based on the closed-Brayton-cycle (CBC) is an excellent technology for thermal protection and power generation of scramjets. In this paper, a comparative study is conducted to investigate the system performance under different supercritical carbon dioxide CBC layouts. A zero-dimensional thermodynamic model was established to analyze the effects of compressor inlet temperature (T 1), turbine inlet temperature (T 3), and compressor outlet pressure (p 2) on fuel mass flow rate for cooling (m f) and net power (P net). A quasi-one-dimensional flow and heat transfer model was developed to study the cooling effectiveness. Results indicate that higher T 3 and p 2 reduce m f while increasing P net in the simple layout (SL) and simple recuperated layout (SRL). However, in the recompressing layout (RCL), the effects of T 1 , T 3 , and p 2 on m f are more complex due to the split ratio. Moreover, RCL has the lowest maximum wall temperature among the three layouts. Finally, after optimization, RCL has the lowest m f about 0.332 kg/s, which is a 19.8 % reduction compared to the regenerative cooling system. Correspondingly, RCL achieves the highest P net , reaching 109.89 kW. In general, the recompressing layout is most suitable for the CBC-based segmented cooling thermal management system for scramjets. [Display omitted] • Different layouts in the segmented cooling thermal management system are compared. • Models address the effects of key parameters on fuel mass flow rate and net power. • Recompressing layout achieves the highest net power, reaching 109.89 kW. • Recompressing layout is most suitable because of the smallest fuel mass flow rate. [ABSTRACT FROM AUTHOR]

Food-derived calcium chelating peptides (CCPs), as a new generation of calcium supplements, offer a promising strategy for addressing the challenge of human calcium nutrition. They are natural and have low toxicity, effectively solving the problems of poor calcium absorption and low bioavailability in the body. Therefore, they have high application value and development prospects in the food industry. This review provided a comprehensive overview from the preparation, purification, and identification to the evaluation of CCPs. The structure-function relationship of CCPs and emerging technologies for estimating CCPs are summarized, with a focus on exploring the gastrointestinal stability of CCPs, the mechanism of promoting calcium absorption, and the progress in improving calcium bioavailability. Conventional purification and identification of CCPs are costly and time-consuming. To overwhelm this challenge, computer-aided mathematical models, quantum mechanical calculations, bioinformatics, and real-time updated protein/peptide databases have been extensively investigated and utilized. However, the effective use of these tools relies on the awareness of the structure-function relationship of CCPs. Currently, an increasing number of CCPs have been discovered from various food sources, and providing insight into the effects of CCPs on calcium bioavailability has special significance for them as functional ingredients or calcium preparations. Future studies should focus on the commercial production of food proteins-derived CCPs on a large scale, comprehensively studying the structure-function relationship of CCPs and validating their health benefits in the human body. [Display omitted] • Calcium chelating peptides (CCPs) have massive potential as functional food ingredients. • CCPs furnish a promising way to fabricate novel calcium supplements. • CCPs enhance the absorption, transport, and release properties of calcium ions. • The structure-function relationship of CCPs is provided for the guidance of mechanism. • The progress of CCPs in calcium bioavailability is reviewed for further application. [ABSTRACT FROM AUTHOR]

The dovetail joint interfaces in aero-engine are susceptible to fretting wear, which can result in premature failure. Based on two-dimensional (2D) blade/disk contact finite element (FE) model and the energy model, an original substrate-debris-glaze conversion method is proposed and validated to predict the presence of a glaze layer at high temperatures in fretting wear. The present work investigates the effects of bottom angle, friction coefficient, centrifugal force and temperature on fretting wear of the dovetail joint. The results indicate that fretting wear predominantly occurs near the edges of the contact areas. Furthermore, the formation of glaze layer at high temperatures leads to a significant reduction in wear depth, ranging from 50% to 93%, compared to low temperatures without glaze layer. [ABSTRACT FROM AUTHOR]

A burner structure suitable for atmospheric entrained-flow gasifiers using fine ash as feedstock was proposed. The study investigates the impact of the burner structure on the mixing characteristics through 0.75:1 (geometry reduction) single-phase airflow experiments. Additionally, numerical simulations were conducted to study of the gasification process of fine ash in a 10,000 Nm3/h atmospheric entrained flow gasifier. The results indicate that a larger residual temperature near the burner outlet was observed when the diameter of the burner's gasification agents channel was 10 mm or 15 mm, approximately 0.7–0.8. Additionally, the mixing degree of the two airflows at the burner outlet was high, and the distance required for complete mixing was short. When the diameter of the gasification agent channel was 15 mm, the mixed syngas flow velocity was appropriate. This resulted in a maximum temperature of 2500 °C, an 80 % carbon conversion rate, and an outlet effective syngas (CO + H 2) concentration of 62 %. • Novel gasifier and burner structures for fine ash gasification are given. • Fine ash is quickly mixed at the outlet of burner and fully mixed in the center of gasifier. • The highest carbon conversion rate of fine ash entrained-flow gasifier is about 80 %. • Gasification agent channel diameter affects the mixing and gasification characteristics. • The outlet temperature exceeds 1600 °C which satisfies the requirement for liquid slag discharge. [ABSTRACT FROM AUTHOR]

The modification based on natural products is a practical way to find anti-inflammatory drugs. In this study, 26 osthole derivatives were synthesized, and their anti-inflammatory properties were evaluated. The preliminary activity study revealed that most osthole derivatives could effectively inhibit inflammatory cytokines IL-6 secretion in LPS stimulated mouse macrophages J774A.1. Compound 7m exhibited the most effective anti-inflammatory activity (RAW264.7 IL-6 IC 50 : 4.57 μM, 32 times more active than osthole) in vitro with no significant influence on cell proliferation. Additionally, the mechanistic analysis demonstrated that compound 7m could block MAPK signal transduction by inhibiting the phosphorylation of JNK and p38, thereby inhibiting the release of inflammatory cytokines. Moreover, in vivo functional investigations revealed that 7m could substantially reduce DSS-induced ulcerative colitis and LPS-induced acute lung injury, with good therapeutic effects. The pharmacokinetics and acute toxicity experiments proved the safety and reliability of 7m in vivo. Overall, Compound 7m could further be studied as potential anti-inflammatory candidate. [Display omitted] • Novel osthole derivatives were designed and synthesized. • The effect was evaluated by the inhibition on pro-inflammatory cytokines release. • 7m could significantly alleviate LPS-induced ALI and DSS-induced UC. • 7m could play anti-inflammatory role through MAPK pathway. [ABSTRACT FROM AUTHOR]

Through a gas-particle cold-modeling experiment, the particle dynamic analyzer (PDA) is used to investigate the effects of fuel-lean coal/airflow angle and ratio of oil secondary air to F-layer secondary air on the gas/particle flows characteristics in the furnace of a Foster Wheeler (FW) down-fired boiler with enhanced stable combustion technology. As the fuel-lean coal/airflow angle increases from 10° to 45°, the peak value of the vertical dimensionless velocity of the gas/particle flows gradually increases, and the peak position gradually moves to the near wall region. As the ratio of oil secondary air to F-layer secondary air (the secondary air ratio for short) increased, the peak value of the vertical dimensionless velocity of the gas/particle flows gradually increased and the peak value position of the dimensionless velocity gradually moved towards the near-wall region. In actual operation, for the perspective of performance and safety, the recommended fuel-lean coal/airflow angle and secondary air ratio is 30°and 1:2 respectively. The enhanced stable combustion technology had been applied to two 600 MW FW down-fired boilers, and these boilers can achieve stable operation when burning a wide range of coal quality under the load section from 200 MW to 600 MW. • A Foster Wheeler down-fired boiler retrofitted with novel low-load stable combustion technology is studied by PDA. • Effects of fuel-lean coal/airflow angle and secondary air ratio on the gas/particle flows characteristics were investigated. • The fuel-lean coal/airflow angle of 30° and the secondary air ratio of 1:2 is recommended. • This novel low-load stable down-fired boiler combustion technology is suitable for a wide range of coal quality combustion. [ABSTRACT FROM AUTHOR]

• Farmland has mainly been converted into construction land in the Huaihe River Basin. • The supply–demand for agroecosystem services are related to farmland loss rate (FLR). • Urbanization patterns strongly impact supply–demand relationship in different FLR area. China's urbanization has gradually become the dominant factor in farmland loss, but it remains unclear how urbanization impacts the supply–demand relationship of agroecosystem services at different rates of farmland loss, which in turn poses new challenges to the ecological security of farmland. Taking the Huaihe River Basin as a case, this paper analyzes farmland loss from 2000 to 2020, as well as changes in the supply–demand relationship of four types of agroecosystem services: food production, socio-economic security, carbon sequestration, and soil conservation, revealing the driving mechanisms of urbanization on the supply–demand relationship of agroecosystem services in sub-regions with different rates of farmland loss. The results show that: (1) A total of 13588.11 km2 of farmland was converted to construction land from 2000 to 2020, accounting for 75.62 % of the total amount of farmland converted to different land types, and 95.57 % of the total amount of farmland converted to construction land. (2) There was a surplus supply of grain production services and socio-economic security services, while there was a deficit in the supply of carbon sequestration services, and a balance in the supply–demand of soil conservation services. (3) The matching degree of supply–demand for agroecosystem services was lower in the Rapid Loss Area compared to the Medium Loss Area and Slow Loss Area. (4) Urbanization was divided into population, economic, and spatial urbanization. The supply–demand relationships of agroecosystem services were impacted greatly by spatial urbanization in the Rapid Loss Area and by economic urbanization in the Medium Loss Area and Slow Loss Area. [ABSTRACT FROM AUTHOR]