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In this review, several mechanisms of antihypertensive peptides derived from food and its by-products were summarized. Mechanisms based on the RAAS system such as ACE/Ang Ⅱ/AT1R signaling pathways and ACE2/Ang (1-7)/MasR signaling pathways were included. Mechanisms targeting at KNOS system including PI3K/Akt/eNOS signaling pathway, PPAR-γ/caspase3/MAPK/eNOS signaling pathway and L-type Ca2+ channel were also discussed. In addition, the pathways of reducing blood pressure by inhibiting endothelin-converting enzyme (ECE) activity discovered in recent years were also introduced.

In order to solve the problem of low first time yield rate of engine clearance size in aircraft assembly plant C Six Sigma DMAIC (define, measure, analyze, improve and control) method was introduced to analyze the engine installation process. Multiple regression analysis and other methods were used to determine the key factors affecting the clearance size and their influence degree, and the optimal parameter range was obtained by linear fit-ting, and a detailed control plan was made. The analysis results of the control chart show that the improved clear-ance size is in a stable state of the process, and the first time yield rate of engine installation has increased from 65.2% before the improvement to 95%. Conclusion:quality control based on Six Sigma DMAIC method has a pos-itive effect on reducing production process variation and improving production efficiency.

Phosphorus (P) starvation in rice facilitates the reutilization of root cell wall P by enhancing the pectin content. NaCl modulates pectin content, however, it is still unknown whether NaCl is also involved in the process of pectin regulated cell wall P remobilization in rice under P starved conditions. In this study, we found that 10 mmol/L NaCl increased the shoot and root biomasses under P deficiency to a remarkable extent, in company with the elevated shoot and root soluble P contents in rice. Further analysis indicated that exogenous NaCl enhanced the root cell wall P mobilization by increasing the pectin methylesterase activity and uronic acid content in pectin suggesting the involvement of NaCl in the process of cell wall P reutilization in P starved rice roots. Additionally, exogenous NaCl up-regulated the expression of P transporter OsPT6, which was induced by P deficiency, suggesting that NaCl also facilitated the P translocation prominently from root to shoot in P starved rice. Moreover, exogenous abscisic acid (ABA) can reverse the NaCl-mediated mitigation under P deficiency, indicating the involvement of ABA in the NaCl regulated root cell wall P reutilization. Taken together, our results demonstrated that NaCl can activate the reutilization of root cell wall P in P starved rice, which is dependent on the ABA accumulation pathway.

In order to improve the activity of Pd catalyst for methanol catalytic oxidation, carbon fiber cloth was prepared by pre-oxidizing PAN/CA fiber cloth and heat-treated at 1 200 ℃, and the surface was loaded with different content of Pd. The microscopic structure of CNFs/Pd catalyst sample and performance testing were analyzed to find the effect of Pd catalyst. The results showed that the performance of the catalyst for electrocatalytic oxidation of methanol increased firstly and then decreased with the concentration increase of the PdCl2 solution. When the concentration of the PdCl2 solution was 0.02 mol/L, the catalyst performance was the best, and its performance and stability were about 3.3 and 10 times of the commercial Pd/C catalyst. Compared with the commercial catalyst, the activity and stability are both improved.

In the final assembly stage of military aircraft,there are problems of high control cost caused by the disconnection between quality control and business process and the lack of advanced quality planning. To solve these problems,insufficient quality planning and high control costs in the military aircraft final assembly stage,APQP(Advanced Product Quality Planning)application guide suitable for the military aircraft final assembly stage is proposed by improving the APQP guidance material of the IAQG(International Aerospace Quality Group),including theoretical models,core content and key elements,etc. The application effect of the military aircraft assembly APQP in process optimization and management,risk identification and control are verified on the aero-engine installation. The results show that the military aircraft assembly APQP is beneficial to predict and reduce risks,reduce process changes,improve military aircraft quality and delivery efficiency.

This article numerically explores the effects of the film hole diameter on the performance of the film and vortex composite cooling. The vortex cooling structure is set in the leading edge of a GE E3 airfoil, connecting with the mainstream flow by the film holes and the blade material to achieve mass transfer and heat transfer, respectively. Five cooling structures with the film diameter d equal to 0.12 mm, 0.20 mm, 0.28 mm, 0.36 mm, and 0.44 mm are involved. Simulations are carried out under the rotating speed of 0 rpm, 1000 rpm, 2000 rpm, 2500 rpm, and 3000 rpm for all structures. The dimensionless temperature θ of the blade leading edge surface is defined to evaluate the cooling performance. The higher θ represents the lower temperature. Results show the different rotational effects on the different structures. First, the value of θ increases with the increasing film hole diameter under the same rotating speed. The value of θ in the case of 0.44 mm is around 5 times that in the case of 0.12 mm. Second, the peak value of θ is observed under the rotating speed higher than 2500 rpm when d is lower than 0.28 mm. While the peak value of θ is observed under 1000 rpm when d is higher or equal to 0.28 mm. The peak value of θ represents an increase of 11.23% and 2.76%, as compared to the lowest value of θ when d is equal to 0.12 mm and 0.44 mm, respectively. Because the dominating cooling methods are different in the cases with different film hole diameters. [ABSTRACT FROM AUTHOR]

This study aimed to explore the traffic safety evaluation model for downstream intersections of urban expressway exits and make up for the shortcomings in safety research on downstream intersections of urban expressway exits. We constructed a comprehensive traffic safety evaluation index system, established a traffic safety evaluation model, and divided precise safety evaluation levels using the AHP–Matter-Element analysis method, establishing a traffic safety evaluation index system consisting of eleven indicators. The effectiveness of this method was validated through an assessment of traffic safety at the intersection of Dongsheng Street and Free Road in Changchun City. A theoretical basis for improving traffic safety at downstream intersections of urban expressways and a reference for subsequent related research were provided. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) network topological structure composite (3D-NTSC) is a new type of composite in which both the matrix phase and the reinforced phase have 3D continuous network structure and interweave with each other. Different from fiber reinforcement and particle reinforcement, the reinforcing phase in the composite material runs through the whole matrix phase in a continuous form without destroying the topological continuity of the matrix phase, so that each matrix phase in the composite material can not only maintain its own excellent performance, but also can cooperate with each other and complement each other, so that the composite material can play a greater performance advantage. In recent years, 3D-NTSC has attracted the attention of researchers and has been widely used in practical production. At present, there are no comprehensive articles summarizing the research progress of this kind of materials. In this review, we discussed the recent progress of the preparation methods, including natural flow method, vacuum infiltration process, pressure filling method, in situ filling method, and co-building method. Furthermore, research progress on mechanical properties and some regular results, shortcomings, challenges, and prospects of 3D-NTSC were also put forward, which would be helpful to people working in the related fields.

When using a wrench, the nut is easily damaged due to improper operation or impact. Although coating a polymer layer on the surface of the wrench can effectively solve the above problem, the layer is easy to be deboned due to the lack of adhesion between the polymer and the surface of the wrench. Herein, we implemented an anodizing treatment strategy on the surface of the wrench to obtain a porous oxide film. Interestingly, during the anodization process, micro-nanopores with a specific diameter can be obtained by adjusting the voltage, temperature, and electrolyte concentration. Furthermore, the ammonium fluoride/ethylene glycol electrolyte was used to etch the formed large hole to form the large hole sleeve small hole structure. In order to inject polyphenylene sulfide (PPS) molecules into multiscale holes to form a pinning effect, we also used nano molding technology to inject PPS into the metal surface. The results showed that the adhesion between PPS and the wrench was greatly improved compared with the commonly used dip coating method.

In this study, Pd/TiO2 decorated carbon nanofibers (Pd/TiO2@CNFs) and Pd@CNFs were prepared by the impregnation method for application in direct methanol fuel cells (DMFCs). Pd and TiO2 particles were supported on the surface of carbon fibers. Noticeably, When the mass fraction of PdCl2 added is 4%, the Pd@CNFs catalyst (Pd‐4@CNFs) showed higher electrocatalytic activity and stability, which were about 28.4 and 13.2 times higher than those of commercial Pd/C catalyst, respectively. On the basis of Pd‐4@CNFs catalyst, TiO2 with a mass fraction of 10% was added to produce Pd/TiO2@CNFs catalyst (Pd‐4/TiO2‐10@CNFs). The electrocatalytic activity of Pd‐4/TiO2‐10@CNFs increased to 3,850.4 A·g−1, which was 31.9 times higher than that of commercial Pd/C catalysts. These results demonstrated that the novel Pd/TiO2@CNFs catalyst is expected to be an efficient and durable catalyst for DMFC. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of carbonization temperature on the electrocatalytic performance of CF/Pd catalysts for methanol oxidation, a series of CF/Pd catalysts were prepared by electrospinning heat treatment carbonization impregnation method. The carbonization temperatures were set at 800, 1 000, and 1 200 ²C, respectively. The obtained CF/Pd catalyst samples were characterized by microscopic morphology, composition analysis, and electrochemical testing. Research has found that at 800 ²C, PAN/CA fibers have completely carbonized, but as the carbonization temperature increases, the degree of fibrosis of CF/Pd catalysts gradually decreases, and the bonding phenomenon becomes more obvious. The electrocatalytic performance of methanol oxidation shows a trend of first increasing and then decreasing. When the carbonization temperature is 1 000 ²C, the CF/Pd catalyst has the best electrocatalytic performance for methanol oxidation, with a catalytic activity 5.4 times that of commercial Pd/ C catalysts and a stability 16. 2 times that of commercial Pd/C catalysts. [ABSTRACT FROM AUTHOR]