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Forming process chain for manufacturing complex conical-section profiled rings:On a co-design method

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Chinese Journal of Aeronautics 2024年第6期37卷 485-503页

作者： Lei liang Chaojiang zou lianggang GUO State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Guizhou Aviation Technology Development Co.Ltd Guiyang 550081China

The final quality of complex conical-section rings depends on co-design of multiple processes in forming process *** this study,for a complex aeroengine casing ring with a large slope and a flange on its end,a co-design method of the forming process chain is put forward towards the objective of precision forming,which not only proposes a standard process route composed of multiple processes of upsetting,punching,rectangular ring rolling,loose tooling forging and profiled ring rolling,but also presents co-design methods of dies and blanks for all the *** profiled ring rolling,a design method of preformed blank that makes the blank and the target conical-section ring have the same axial volume distribution is *** the method,the axial metal redistribution during the process can be alleviated greatly thus improving the forming stability and precision of the *** on the geometric features of designed preformed blank,design methods of blanks and dies for loose tolling forging,rectangular ring rolling,punching and upsetting are proposed *** view of the key roles of loose tooling forging(manufacturing the preformed blank)and profiled ring rolling on the final quality of the conical ring parts,inherited FE simulations for these two processes are performed to verify the proposed design methods and determine appropriate design *** is demonstrated that the proposed design method has significant advantages in improving forming ***,a suggestive value 1.5 of the rolling ratio for profiled ring rolling(a key design parameter)is given based on comprehensive consideration of multiple indicators such as ring roundness,deformation uniformity and forming *** corresponding industrial experiments performed illustrate that a high forming precision of the conical-section aeroengine casing ring is achieved.

关键词： Complex conical-section ring Co-design of forming process chain Profiled ringrolling Preformed blank Loose tooling forging

Big Theta Equals Small Theta Generically

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Acta Mathematica Sinica,English Series 2024年第3期40卷 717-730页

作者： Rui CHEN Jia liang zou Institute for Advanced Study in Mathmatics Zhejiang UniversityHangzhou 310058P.R.China Department of Mathematics University of Michigan530 Church StAnn ArborMI 48109USA

In this paper we consider the theta correspondence over a non-Archimedean local *** the homological method and the theory of derivatives,we show that under a mild condition the bigtheta lift is irreducible.

关键词： Theta correspondence derivatives

Effects of vitamin family members on insulin resistance and diabetes complications

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World Journal of Diabetes 2024年第3期15卷 568-571页

作者： Hong-Jin Chen min Wang Ding-min zou Gui-You liang Si-Yuan Yang Division of Cardiac Surgery Guizhou Institute of Precision MedicineThe Affiliated Hospital of Guizhou Medical UniversityGuiyang 550009Guizhou ProvinceChina Translational Medicine Research Center Guizhou Medical UniversityGuiyang 550025Guizhou ProvinceChina School of Basic Medical Sciences/School of Biology and Engineering Guizhou Medical UniversityGuiyang 550025Guizhou ProvinceChina

The following letter to the editor highlights the article“Effects of vitamin D supplementation on glucose and lipid metabolism in patients with type 2 diabetes mellitus and risk factors for insulin resistance”in World J Diabetes 2023 Oct 15;14(10):*** is necessary to explore the role of vitamin family members in insulin resistance and diabetes complications.

关键词： Vitamin Insulin resistance Diabetes complications Letter

The low Mach number limit of non-isentropic magnetohydrodynamic equations with large temperature variations in bounded domains

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Science China Mathematics 2024年第4期67卷 787-818页

作者： min liang Yaobin Ou School of Mathematics Renmin University of ChinaBeijing 100872China

This paper verifies the low Mach number limit of the non-isentropic compressible magnetohydrodynamic(MHD)equations with or without the magnetic diffusion in a three-dimensional bounded domain when the temperature variation is large but *** uniform estimates of strong solutions are established in a short time interval independent of the Mach number,provided that the slip boundary condition for the velocity and the Neumann boundary condition for the temperature are imposed and the initial data is well-prepared.

关键词： low Mach number limit non-isentropic compressible magnetohydrodynamic equations large temperature variations bounded domains

Arbuscular mycorrhizal fungi and endophytic fungi differentially modulate polyamines or proline of peach in response to soil flooding

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Pedosphere 2024年第2期34卷 460-472页

作者： Shengmin liang Yingning zou Bo SHU Qiangsheng WU ministry of Education Engineering Research Center of Ecology and Agricultural Use of WetlandHubei Key Laboratory of Waterlogging Disaster and Agricultural Use of WetlandCollege of Horticulture and GardeningYangtze UniversityJingzhou 434025China

Symbiotic fungi are involved in plant flooding tolerance,while the underlying mechanism is not yet *** polyamines(PAs)and proline are also associated with stress tolerance,it is hypothesized that the enhancement of stress resistance by symbiotic fungi is associated with changes in PAs and/or *** aim of this study was to analyze the effect of inoculation with Funneliformis mosseae and Serendipita indica on plant growth,PAs,and proline and the metabolisms in peach(Prunus persica)under ***-week flooding did not affect root colonization frequence of ***,while it promoted root colonization frequence of *** flooding,plants inoculated with *** and *** maintained relatively higher growth rates than uninoculated *** mosseae promoted root ornithine(Orn)contentration and arginine(Arg)and Orn decarboxylase activities under flooding,which promoted putrescine(Put),cadaverine(Cad),and spermidine(Spd)***,*** decreased contentrations of Arg,Orn,and agmatine and Arg decarboxylase activities,thus decreasing PA contentrations under *** were negatively correlated with the expression of PA uptake transporter genes,PpPUT1 and PpPUT2,in *** transporter genes of ***(FmTPO)and ***(SiTPO)were regulated by flooding,of which FmTPO1 was positively correlated with Put,Cad,and Spd,along with positive correlations of Spd with SiTPO1,SiTPO2,and *** flooding,*** decreased proline concentration,while *** increased proline concentration and correlated with expression of a△^(1)-pyrroline-5-carboxylate synthetase gene,*** was thus concluded that *** modulated polyamine accumulation,while *** induced proline accumulation to tolerate flooding.

关键词： △^(1)-pyrroline-5-carboxylate synthetase flooding tolerance Funneliformis mosseae ornithine aminotransferase root colonization Serendipita indica spermidine transporter

Ligand-controlled NiH-catalyzed regiodivergent hydroalkylation of 2-alkenylazaarenes

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Science China Chemistry 2024年第6期67卷 1935-1940页

作者： Ya-Ping Shao Zhuo-min Chi Yong-min liang State Key Laboratory of Applied Organic Chemistry School of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou730000China

A nickel-hydride(Ni H)-catalyzed migratory and nonmigratory hydroalkylation reaction of 2-alkenyl azaarenes with alkyl iodines has been established through strategic modulation of N-or P-donor *** method enables the synthesis of diverseβ-orγ-branched aromatic *** mild regiodivergent protocols exhibit wide substrate scope,excellent functional tolerance,and great reaction yield with remarkable ***,deuterium labeling studies reveal Ni H-catalyzed interrupted chain-walking mode as the mechanism behind remotedβ-selective hydroalkylation reaction—an interesting phenomenon mediated through aromatic imine directing groups.

关键词： NiH regiodivergent hydroalkylation azaarenes interrupted chain-walking

Review and comparison of methods and benchmarks for automatic modal identification based on stabilization diagram

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 209-224页

作者： min He Peng liang Jiuxian Liu Zhiqiang liang School of Architecture and Civil Engineering Xi'an University of Science and TechnologyXi'an 710064China School of Highway Chang'an UniversityXi'an 710064China

Automatic modal identification via automatically interpreting the stabilization diagram provides key technique in bridge structural health *** paper reviews the progress in the area of automatic modal identification based on interpreting the stabilization *** whole identification process is divided into four steps from establishing the stabilization diagram to removing the outliers in the identification *** criteria and algorithms used in each step in the existing studies are carefully summarized and *** between typical methods in cleaning and interpreting the stabilization diagram are also *** structure benchmarks used in the existing studies to validate the proposed automatic modal identification methods are also *** on the review and comparison,the specific ratio method for cleaning the stabilization diagram,the hierarchical clustering method for interpreting the stabilization diagram and the adjusted boxplot for removing the outliers in the identification results are the most suitable methods for each *** key point of automatic modal identification based on interpreting the stabilization diagram has also discussed,and it is recommended to pay more attention to cleaning the stabilization *** study about automatic modal identification under situation with very few sensors deployed should be more *** review aims to help researchers and practitioners in implementing existing automatic modal identification algorithms effectively and developing more suitable and practical methods for civil engineering structures in the future.

关键词： Bridge structural health monitoring Automatic modal identification Stabilization diagram Eriteria and methods Real structure benchmarks

Comprehensive evaluation of multi-energy complementary ecosystem based on improved multicriteria decision-making method

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CLEAN ENERGY 2024年第1期8卷 226-236页

作者： Huang, Shuyi zou, Xuetong liang, Huaguang Chen, Jie China Southern Power Grid Shenzhen Power Supply Bur Shenzhen 518048 Peoples R China

The multi-energy complementary ecosystem is an important form of the modern energy system. However, standardized evaluation criteria and the corresponding method framework have not yet been formed, resulting in unclear standards and irregular processes of its construction. To cope with this issue, a novel comprehensive evaluation framework for multi-energy complementary ecosystems is proposed in this study. First, a 5D comprehensive evaluation criteria system, including environment, economy, technology, safety and systematicness, is constructed. Then, a novel multicriteria decision-making model integrating an analytic network process, entropy and preference-ranking organization method for enrichment evaluation under an intuitional fuzzy environment is proposed. Finally, four practical cases are used for model testing and empirical analysis. The results of the research show that the unit cost of the energy supply and the internal rate of return indexes have the highest weights of 0.142 and 0.010, respectively. It means that they are the focus in the construction of a multi-energy complementary ecosystem. The net flows of four cases are 0.015, 0.123, -0.132 and -0.005, indicating that cases with a variety of energy supply forms and using intelligent management and control platforms to achieve cold, heat and electrical coupling have more advantages. A novel evaluation framework for multi-energy ecosystems is developed based on 5 criteria and using a multicriteria decision-making model integrating an analytic network process, entropy and preference-ranking organization method in an intuitional fuzzy environment. Four practical cases are used for model testing and empirical analysis. Graphical Abstract

关键词： multi-energy complementary ecosystem comprehensive evaluation intuitionistic fuzzy multicriteria decision-making OPTIMAL-DESIGN SYSTEMS CHINA

Securing offshore resources development: A mathematical investigation into gas leakage in long-distance flexible pipes

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Petroleum Science 2024年第4期21卷 2734-2744页

作者： Xiang-An Lu liang-liang Jiang Jian-Sheng Zhang min-Gui Wang Guangling College of Yangzhou University Department of Chemical and Petroleum Engineering University of Calgary Department of Energy and Power Engineering Tsinghua University

Gas flexible pipes are critical multi-layered equipment for offshore oil and gas development. Under high pressure conditions, small molecular components of natural gas dissolve into the polymer inner liner of the flexible pipes and further diffuse into the annular space, incurring annular pressure build-up and/or production of acidic environment, which poses serious challenges to the structure and integrity of the flexible pipes. Gas permeation in pipes is a complex phenomenon governed by various factors such as internal pressure and temperature, annular structure, external temperature. In a long-distance gas flexible pipe, moreover, gas permeation exhibits non-uniform features, and the gas permeated into the annular space flows along the metal gap. To assess the complex gas transport behavior in long-distance gas flexible pipes, a mathematical model is established in this paper considering the multiphase flow phenomena inside the flexible pipes, the diffusion of gas in the inner liner, and the gas seepage in the annular space under varying permeable properties of the annulus. In addition, the effect of a variable temperature is accounted. A numerical calculation method is accordingly constructed to solve the coupling mathematical equations. The annular permeability was shown to significantly influence the distribution of annular pressure. As permeability increases, the annular pressure tends to become more uniform, and the annular pressure at the wellhead rises more rapidly. After annular pressure relief followed by shut-in, the pressure increase follows a convex function. By simulating the pressure recovery pattern after pressure relief and comparing it with test results, we deduce that the annular permeability lies between 123 and 512 m D. The results help shed light upon assessing the annular pressure in long distance gas flexible pipes and thus ensure the security of gas transport in the emerging development of offshore resources.

关键词： Offshore resources development Transport security Long-distance flexible pipes Gas leakage Heat and mass transfer model Finite difference calculation