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Journal of Iron and Steel Research International 2024年第3期31卷 710-718页

作者： yan-hui Hou Ze-kun Xu Shi-long Zhou Guang-qiang Li The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Three-dimensional atom-probe tomography and first-principles calculation combined with density functional theory were used to study the effect of the co-segregation of different elements formed during the solidification process of S32205 duplex stainless steel on the Cr-depleted zone at the interface between ferrite and *** was found that the co-segregation of different elements formed during the solidification process of duplex stainless steel can also form Cr-depleted zone at the interface between ferrite and ***,Mo,Si,B,C and P atoms promote co-segregation with Cr atoms,which promotes the formation of Cr-depleted zone at the interface between ferrite and austenite in duplex stainless *** and Si strongly promote the segregation of Cr at the interface between ferrite and austenite,thereby promoting the formation of Cr-depleted zone.B,C and P elements also promote the segregation of Cr element at the interface between ferrite and austenite and the formation of Cr-depleted zone,but their effect is weaker than that of Mo and Si *** conclusions provide a new theoretical basis for improving the intergranular corrosion performance of duplex stainless steel.

关键词： Duplex stainless steel Cr-depleted zone Intergranular corrosion Co-segregation First-principles calculation

Critical Role of Ethylene-Propylene Block Copolymer in Impact Polypropylene Copolymer

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Chinese Journal of Polymer Science 2024年第3期42卷 344-351,I0007页

作者： Yu-hui Tang Na zhang Wei Bao Wei Jiang Yuan Lin Zhao-hui Su State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Ethylene-propylene block copolymer(EbP) is a vital component in impact polypropylene copolymer(IPC), yet its distribution in the multiphase composite material and how it influences the phase structure and the mechanical properties are not well understood. In this work,four IPCs were investigated by atomic force microscopy-infrared(AFM-IR) to assess the phase compositions in situ, based on which in conjunction with the chain microstructure information obtained ex situ the distributions of the copolymer components were derived for each alloy. For the IPCs whose EbP comprises long P and long E segments, the EbP fraction was found to phase separate from the rubber and the PP matrix to form the cores of the disperse particles with the E-P segmented copolymer(EsP). In contrast, in the IPC with EbP composed of long P and short E segments, the EbP fraction formed an outer shell for the rubber particles with the cores comprising the EsP alone, and this IPC, containing a lower E comonomer content than its counterpart, exhibited both better impact resistance and higher flexural modulus. These results clarify how the chain structure of EbP governs the phase morphology in IPC, which in turn impacts the properties of the composite material.

关键词： Impact polypropylene copolymers AFM-IR Ethylene-propylene block copolymers Core-shell rubber particles

Multi-blade rubbing characteristics of the shaft-disk-blade-casing system with large rotation

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 111-136页

作者： Zhiyuan WU Linchuan ZHAO Han yan Ge yan Ao CHEN Wenming zhang State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Institute of Aerospace Systems Engineering Shanghai 201108China

Blade rubbing faults cause detrimental impact on the operation of aeroengines. Most of the existing studies on blade rubbing in the shaft-disk-blade-casing(SDBC) system have overlooked the elastic deformation of the blade, while some only consider the whirl of the rotor, neglecting its spin. To address these limitations, this paper proposes a dynamic model with large rotation for the SDBC system. The model incorporates the spin and whirl of the rotor, enabling the realistic reproduction of multiblade rubbing faults. To verify the accuracy of the SDBC model with large rotation and demonstrate its capability to effectively consider the rotational effects such as the centrifugal stiffening and gyroscopic effects, the natural characteristics and dynamic responses of the proposed model are compared with those obtained from reported research and experimental results. Furthermore, the effects of the rotating speed, contact stiffness,and blade number on the dynamic characteristics of the SDBC system with multi-blade rubbing are investigated. The results indicate that the phase angle between the rotor deflection and the unbalance excitation force increases with the increasing rotating speed,which significantly influences the rubbing penetration of each blade. The natural frequency of the SDBC system with rubbing constrain can be observed in the acceleration response of the casing and the torsional response of the shaft, and the frequency is related to the contact stiffness. Moreover, the vibration amplitude increases significantly with the product of the blade number under rubbing, and the rotating frequency approaches the natural frequency of the SDBC system. The proposed model can provide valuable insight for the fault diagnosis of rubbing in bladed rotating machinery.

关键词： shaft-disk-blade-casing(SDBC) large rotation spin and whirl multi-blade rubbing rotational effect

OsATL32 ubiquitinates the reactive oxygen species-producing OsRac5-OsRbohB module to suppress rice immunity

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Journal of Integrative Plant Biology 2024年第7期66卷 1459-1480页

作者： Yuqing yan hui Wang yan Bi Jiajing Wang Muhammad Noman Dayong Li Fengming Song National Key Laboratory for Rice Biology and Breeding Institute of BiotechnologyZhejiang UniversityHangzhou 310058China Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insect Pests Institute of BiotechnologyZhejiang UniversityHangzhou 310058China Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province Institute of BiotechnologyZhejiang UniversityHangzhou 310058China

Ubiquitination-mediated protein degradation is integral to plant immunity,with E3 ubiquitin ligases acting as key factors in this ***,we report the functions of OsATL32,a plasma membrane-localized Arabidopsis Tóxicos En Levadura(ATL)-type E3 ubiquitin ligase,in rice(Oryza sativa)immunity and its associated regulatory *** found that the expression of OsATL32 is downregulated in both compatible and incompatible interactions between rice and the rice blast fungus Magnaporthe *** OsATL32 protein level declines in response to infection by a compatible *** strain or to chitin ***32 negatively regulates rice resistance to blast and bacterial leaf blight diseases,as well as chitin-triggered *** and genetic studies revealed that OsATL32 suppresses pathogen-induced reactive oxygen species(ROS)accumulation by mediating ubiquitination and degradation of the ROS-producing OsRac5–OsRbohB module,which enhances rice immunity against *** protein phosphatase PHOSPHATASE AND TENSIN HOMOLOG enhances rice blast resistance by dephosphorylating OsATL32 and promoting its degradation,preventing its negative effect on rice *** study provides insights into the molecular mechanism by which the E3 ligase OsATL32 targets a ROS-producing module to undermine rice immunity.

关键词： E3 ligase OsATL32 OsRac5-OsRbohB module phosphatase OsPTEN reactive oxygen species rice immunity

PVR update:pathophysiology and clinical management

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International Journal of Ophthalmology(English edition) 2024年第9期17卷 1577-1580页

作者： Peter Wiedemann yan-Nian hui Medical Faculty Leipzig UniversityLeipzig 04103Germany Department of Ophthalmology Eye Institute of Chinese PLAXijing HospitalFourth Military Medical UniversityXi’an 710032Shaanxi ProvinceChina

Wound-healing diseases present complex challenges,and proliferative vitreoretinopathy(PVR)has been a problem in the surgical retina for *** is a prolonged and abnormal healing response to retinal injury,such as primary retinal detachment(RD)or post-RD surgery,characterized by the formation of pre/subretinal membranes,retinal gliosis and shortening,retinal pigment epithelium cell(RPE)proliferation,and increased activity of glial cells(mainly Müller cells).

关键词： healing epithelium diseases

Insights into in-situ imbibition behavior of fracturing fluid in propped shale fractures based on nuclear magnetic resonance:A case study from Longmaxi Formation shale,Sichuan Basin,China

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Petroleum Science 2024年第1期21卷 410-429页

作者： Jing-Jing Guo Kai-Xiang Di Lie-hui zhang Yu-Long Zhao hui-Ying Tang Rui-Han zhang Ye Tian National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina

Shale gas is an important component of unconventional oil and gas *** the imbibition behavior is helpful to optimize flowback parameters and enhance gas *** imbibition studies have focused on shale matrix,and the pressure conditions discussed were mostly *** initial imbibition behavior begins from propped fractures to matrix,but there are few studies working on explaining the imbibition behavior in propped fractures or the phenomenon of many shale wells exhibit higher productivity after a“soaking”***,propped fracture samples were designed for imbibition and migration *** order to accurately study the mechanism and main influencing factors of fracturing fluid imbibition and migration in propped and unpropped shale fractures under high temperature and high pressure,a series of experiments based on nuclear magnetic resonance(NMR)were carried *** showed that NMR T_(2) spectra of all samples exhibited a bimodal *** final imbibition volume of fracturing fluid was positively related to pressure and fracture *** imbibition effect of fracturing fluid was more evident in matrix pores under high *** the migration during soaking stage,the fracturing fluid gradually migrated from large pores to small pores and gradually displaced the shale gas from the matrix,thus allowing the water blocking in propped fractures to self-unlock to some *** permeability decreased in the imbibition stage,while it recovered in the migration stage to some extent.

关键词： Forced imbibition Migration Soaking NMR T_(2)spectra Propped fracture Permeability recovery

Serum lipids and other risk factors for diabetic retinopathy in Chinese type 2 diabetic patients

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第5期14卷 392-399页

作者： hui-yan zhang Jian-yong WANG Gui-shuang YING Li-ping SHEN Zhe zhang Hangzhou Vocational & Technical College Department of Ophthalmology the First Affiliated HospitalSchool of MedicineZhejiang University Center for Preventive Ophthalmology and Biostatistics Department of OphthalmologyPerelman School of MedicineUniversity of Pennsylvania Department of Endocrinology the First Affiliated HospitalSchool of MedicineZhejiang University

Objective: To investigate the association of serum lipids and other risk factors with diabetic retinopathy (DR) in Chinese type 2 diabetic patients. Methods: Five hundred and twenty-three type 2 diabetic patients underwent ophthalmic examination by experienced retinal specialists to assess their DR. Serum lipids, including triglycerides, total cholesterol, high density lipoprotein cholesterol (HDLC), and low density lipoprotein cholesterol (LDLC), were measured using Roche automated clinical chemistry analyzers. The concentration of very low density lipoprotein cholesterol (VLDLC) was calculated based on total cholesterol, HDLC and LDLC. Hyperlipidemia was defined as a total cholesterol concentration of 6.2 mmol/L or higher or the use of lipid-lowering medications. The association of risk factors with any DR or proliferative diabetic retinopathy (PDR) was assessed using the odds ratio (OR) and its 95% confidence interval (CI), calculated from logistic regression models. Results: In multivariate logistic regression models, hyperlipidemia (OR=2.39, 95% CI: 1.02-5.66), higher VLDLC (OR=1.59, 95% CI: 1.14-2.23), and higher triglyceride (OR=1.18, 95% CI: 1.03-1.37) were associated with increased risk of DR. A longer diabetic duration was associated with increased risk of DR (P<0.0001) and PDR (P=0.002) in a dose-response manner. Higher systolic blood pressure (P=0.02) and higher serum creatinine (P=0.01) were independently associated with increased risk of DR, and female gender was associated with increased risk of PDR (P=0.03). Conclusions: Among Chinese type 2 diabetic patients, hyperlipidemia, higher VLDLC, and higher triglyceride were independently associated with increased risk of DR, suggesting control of serum lipids may decrease the risk of DR.

关键词： Diabetic retinopathy Serum lipids Risk factors

Energy absorption behaviors of a novel buffer lander-leg with Yoshimura core

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Chinese Journal of Aeronautics 2024年第4期37卷 333-342页

作者： yan XU He HUANG Chao zhang Rongji FU School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310027China School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical UniversityXi’an 710072China

In the current soft-landing system,the lander-leg and the buffer are two independent parts which may cause weight *** traditional mechanical buffers also have their own shortcomings such as small buffer stroke and being non-reusable.A Novel Buffer Lander-leg with Yoshimura core (NBLY) is proposed in this paper,inspired by the Buckling Restrained Brace(BRB).The design details of NBLY and parameter definitions of the core are *** finite element analysis modes have been employed to analyze the nonlinear mechanical behaviors of NBLY subjected to the cyclic *** with four different core styles of hexagon,octagon,dodecagon and hexadecagon are analyzed and *** restraining ratio and cumulative dissipation energy ratio have been obtained to evaluate the energy absorption *** results show that the origami pattern has significant influences on the deformation ductility,plastic energy absorbing and axial load transferring to the *** NBLY with octagon core has outstanding properties,especially the hysteretic energy dissipation and enhancement of compression *** interaction mechanism between the core and encasing member constrains the deformation extensions and contributes to the frictional energy dissipation of the *** paper provides a new conceptual design of buffer lander-leg for soft-landing *** can realize the reuse function as a buffer lander-leg with better loading-bearing and energy absorption behaviors.

关键词： Lander-leg structure Origami Energy absorption Cyclic loading Finite element analysis

Elucidation of the last steps of photo-ammonification:analytical method development and mechanism elucidation

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Frontiers of Environmental Science & Engineering 2024年第8期18卷 101-106页

作者： Yingjing Miao hui Wang Chunpeng yang Ruochun zhang Hao zhang Peizhe Sun School of Environmental Science and Engineering Tianjin UniversityTianjin 300072China SINOPEC Research Institute of Petroleum Processing Co. Ltd.Beijing 100083China School of Earth System Science Tianjin UniversityTianjin 300072China

The mechanisms underlying the photo-ammonification of nitrogenous organic compounds(NOCs)remain unclear,partly due to the analytical challenges of small NOC *** study introduced a simple methodology for accurately and simultaneously quantifying multiple small NOCs during ammonification *** developed method employed phenyl isothiocyanate as derivatization reagents,followed by high-performance liquid chromatography analysis to measure primary and secondary amines,amides,as well as NH4+over variable photo-ammonification *** our experimental setup,vacuum ultraviolet(VUV)irradiation serves as the controlled reaction environment to simulate harsh photo-ammonification *** NOCs,including pyridine,N,N-dimethylformamide,and acrylonitrile,were chosen due to their structural diversity and environmental relevance as model *** method was able to achieve excellent nitrogen mass balance,and revealed that the last steps of photo-ammonification involved oxidation of nitrogen-adjacent carbon to amide followed by the cleavage of N-C *** novel method may also help quantitative investigation of nitrogen transformations in different environmental contexts.

关键词： Ammonification NOCs Amines Nitrogen mass balance

Velocity-Incorporated Wear Model of Rolling Guide Shoe Material Selection

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 118-135页

作者： Longye Chen Lingyu yan Chengliang Liu Zhinan zhang School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

To ensure an accurate selection of rolling guide shoe materials,an analysis of the intricate relationship between linear speed and wear is *** element simulations and experimental measurements are employed to evaluate four distinct types of materials:polyurethane,rubber,polytetrafluoroethylene(PTFE),and *** speed-index of each material is measured,serving as a preparation for subsequent ***,the velocity-wear factor is determined,providing insights into the resilience and durability of the material across varying ***,a wear model tailored specifically for viscoelastic bodies is explored,which is pivotal in understanding the wear mechanisms within the *** this model,wear predictions are made under higher speed conditions,facilitating the choice of material for rolling guide *** validate the accuracy of the model,the predicted degree of wear is compared with experimental data,ensuring its alignment with both theoretical principles and real-world *** comprehensive analysis has verified the effectiveness of the model in the selection of materials under high-speed conditions,thereby offering confidence in its reliability and ensuring optimal performance.

关键词： Archard model Wear model Speed-index Wear prediction