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Journal of hydrodynamics 2010年第3期22卷 312-318页

作者： li Jie LU Chuan-jing hUANG xuan Department of Engineering Mechanics Shanghai Jiao Tong University Shanghai 200240 China Department of Engineering Mechanics Shanghai Jiao Tong University Shanghai 200240 China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200030 China

A numerical method is developed to obtain the added mass coefficients of a vehicle running with cavity in numerical simulation for the multiphase flow of the vehicle which is imposed an added vibration and analyzing its hydrodynamic loads. The method is verified through the cases of non-cavitating sphere and ellipsoid. The changing rule of the added mass of a sphere during water exit is gained. Then the influence of cavitation on the added mass of a cylinder is studied. The results show that λ 11, λ22, λ26, λ66 all decrease as the cavitation number reduces and the length of the attached cavity increases. There is almost a linear relationship between the cavity length and λ22 .The base cavity has great influence on λ11 its contribution decreases more than 60%, when the cavitation number changes from 0.6 to 0.2.

关键词： added mass cavity carrying forced vibration method

PROPERTIES Of NATURAL CAVITATION fLOWS AROUND A 2-D WEDGE IN ShALLOW WATER

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Journal of hydrodynamics 2011年第6期23卷 730-736页

作者： chen xin LU Chuan-jing li Jie chen ying Department of Engineering Mechanics Shanghai Jiao Tong University Shanghai 200240 China Department of Engineering Mechanics and State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200240 China

When a body navigates with cavity in shallow water, both flexible free surface and rigid bottom wall will produce great influences on the cavity shape and hydrodynamic performances, and further affect the motion attitude and stability of the body. In the present work, characteristics of the natural cavitating flow around a 2-D symmetrical wedge in shallow water were investigated and the influences of two type boundaries on the flow pattern were analyzed. The Volume Of fluid （VOf） multiphase flow method which is suitable for free surface problems was utilized, coupled with a natural cavitation model to deal with the mass-transfer process between liquid and vapor phases. Within the range of the cavitation number for computation （0.07-1.81）, the cavity configurations would be divided into three types, viz., stable type, transition type and wake-vortex type. In this article, the shapes of the free surface and the cavity surface, and the hydrodynamic performance of the wedge were discussed under the conditions of relatively small cavitation number （〈0.256）. The present numerical cavity lengths generally accord with experimental data. When the cavitation number was decreased, the cavity was found to become longer and thicker, and the scope of the deformation of the free surface also gradually extends. The free surface and the upper cavity surface correspond fairly to their shapes. however, the lower side of the cavity surface was rather leveled due to the influence of wall boundary. The lift and drag coefficients of this 2-D wedge basically keep linear relations with the natural cavitation number smaller than 0.157, whereas direct proportion for drag and inverse proportion for lift.

关键词： shallow water natural cavitation boundary effect multiphase flow

Martensitic Transformation in fe-Mn-Si Based Shape Memory Alloys

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Journal of Materials Science & Technology 1999年第2期15卷 111-116页

作者： T. y. hsu (xU Zuyao)(shanghai jiao tong university, shanghai 200030, china) shanghai jiao tong university Shanghai 200030 China Chinese Academy of Sciences China

The critical driving force for martensitic transformation fcc ( gamma ) yields hcp ( epsilon ) in ternary fe-Mn-Si alloys increases with the content of Mn and decreases with that of Si. Thermodynamical prediction of M//s in ternary fe-Mn-Si alloys was established. The fcc ( gamma ) yields hcp ( epsilon ) martensitic transformation in fe-Mn-Si is a semi-thermoelastic and the nucleation process does not strongly depend on soft mode. Nucleation occurs directly through an overlapping of stacking fault rather than pole mechanism, and it is suggested that stacking fault energy (SfE) is the main factor controlling nucleation. Based on the phenomenological theory of martensite crystallography, a shuffle on (0001)//h//c//p plane is required when d//1//1//1 does not equal d//0//0//0//2. The derived principal strain in Bain distortion is smaller, i, e., more reasonable than the values given by Christian. Alloying elements strengthening the austenite, lowering SfE of gamma phase and reducing T//N** gamma temperature may be beneficial to shape memory effect of fe-Mn-Si based alloys. Accordingly, fe-Mn-Si-RE and fe-Mn-Si-Cr-N (or fe-Mn-Si-Ni-Cr-N) are worthy to be recommended as shape memory materials with improved shape memory effect. (Edited author abstract) 48 Refs.

关键词： Mn Martensitic Transformation in fe-Mn-Si Based Shape Memory Alloys fe Si

Peripheral mitochondrial DNA as a neuroinflammatory biomarker for major depressive disorder

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Neural Regeneration Research 2025年第6期20卷 1541-1554页

作者： Jinmei ye Cong Duan Jiaxin han Jinrong chen Ning sun yuan li Tifei yuan Daihui Peng Division of Mood Disorder Shanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghaiChina Department of Psychiatry First Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina shanghai Key Laboratory of Psychotic Disorders Brain Health InstituteNational Center for Mental DisordersShanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghaiChina Co-Innovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina

In the pathogenesis of major depressive disorder, chronic stress-related neuroinflammation hinders favorable prognosis and antidepressant response. Mitochondrial DNA may be an inflammatory trigger, after its release from stress-induced dysfunctional central nervous system mitochondria into peripheral circulation. This evidence supports the potential use of peripheral mitochondrial DNA as a neuroinflammatory biomarker for the diagnosis and treatment of major depressive disorder. herein, we critically review the neuroinflammation theory in major depressive disorder, providing compelling evidence that mitochondrial DNA release acts as a critical biological substrate, and that it constitutes the neuroinflammatory disease pathway. After its release, mitochondrial DNA can be carried in the exosomes and transported to extracellular spaces in the central nervous system and peripheral circulation. Detectable exosomes render encaged mitochondrial DNA relatively stable. This mitochondrial DNA in peripheral circulation can thus be directly detected in clinical practice. These characteristics illustrate the potential for mitochondrial DNA to serve as an innovative clinical biomarker and molecular treatment target for major depressive disorder. This review also highlights the future potential value of clinical applications combining mitochondrial DNA with a panel of other biomarkers, to improve diagnostic precision in major depressive disorder.

关键词： biomarker cytokine exosomes inflammasome major depressive disorder microglia mitochondrial DNA mitochondrial dysfunction neuroinflammation Toll-like receptor

EffECT Of REINfORCEMENT VOLUME fRACTION ON PRECIPITATION IN MATRIx Of SiC_p/AI COMPOSITE

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Acta Metallurgica Sinica(English Letters) 1993年第8期6卷 161-167页

作者： liN Junshan li Pengxing WU Renjie shanghai jiao tong university,shanghai,china postdoctoral,Institute of Composite Materials,shanghai jiaotong university,shanghai 200030,china shanghai jiaotong Univ Shanghai China

The differential scanning calorimetric(DSC) and transmission electron microanalysis (TEM) techniques were used to study the kinetic process of precipitation in matrix of cast SiC_p/2024 *** results showed that precipitation reactions of GP zone and intermediate phase S'(Al_2CuMg)in the composites were accelerated compared with SiC-free material,the peak temperatures of both reactions were *** reaction enthalpies of both the GP zone and intermediate phase S' formation in the matrix were substantially decreased after the addition of *** analysis found that the alloying element Mg segregated at the SiC/Al interfaces,and was depleted in the matrix near the *** precipitation-free zones(PfZ) and precipitation-sparse zones(PSZ) formed near the interfaces,as a results,the volume fraction of precipitates in matrix was reduced.

关键词： SiC_p/2024 composite differential scanning calorimetry precipitation in matrix

Computer Simulation of the Structure and Propertiesof Nanocrystals

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Journal of Materials Science & Technology 1994年第6期10卷 418-424页

作者： Da chen(Dept. of Materials Science, shanghai jiao tong university, shanghai, 200030, china) shanghai jiao tong Univ Shanghai China

This paper provides a computer modeling method for the study of nanocrystals. Structural features,such as the boundary component proportion, the reduced density proportion, the excess lattice parameter, and the radial distribution function, have been atomistically simulated. The energy and elastic properties also have been investigated. Simulation results indicate that the structure of grain boundaries in nanocrystals is different from those of the amorphous and the gas, or rather, it is a special structure with some degree of short-range order. Moreover, the structure of crystallites is not entirely the same as that in the perfect crystal lattice. The present simulation method may become one of the foundations of the theoretical study of nanocrystals.

关键词： Simulation Computer Simulation of the Structure and Propertiesof Nanocrystals BDV

A STEEL MATRIx WEAR RESISTANT COMPOSITE REINfORCED By IN-SITU GRANULAR EUTECTICS

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Acta Metallurgica Sinica(English Letters) 2001年第2期14卷 79-84页

作者： Z.M. xu, T.x. li and J.G. li (School of Materials Science and Engineering, shanghai jiao tong university, shanghai 200030, china) Sch. of Mat. Sci. and Eng. Shanghai Jiaotong Univ. Shanghai 200030 China

A new steel matrix wear resistant composite reinforced by in situ granular eutectics can be obtained by modifying with a Si-Ce-Ti compound in the steel melt. The result indicates that the in situ granular eutectic is a pseudo-eutectic of austenite and (fe,Mn)3C, which is formed between austenite dendrites during solidification due to the segregation of C and Mn impelled by modifying elements. The quantity of in situ granular eutectic reaches up to 8%-12% and its grain size is in the range from 10um to 20um. The austenite steel matrix wear resistant composite reinforced by in situ granular eutectic (abbreviated AGE composite) and austenite-bainite steel mains wear resistant composite reinforced by in situ granular eutectic (abbreviated ABGE composite) are obtained in the as-cast state and by air hardening, respectively. The wear resistance of the AGE and ABGE composites can be more greatly increased than that of their matrix steels under low and medium impact working condition.

关键词： steel matrix composite Si-Ce-Ti compound in situ granular eutectic mechanical property

Static Analysis of Collision Strength of Offshore Platform

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china Ocean Engineering 1996年第1期11卷 45-54页

作者： li Runpei chen Weigang Gu yongning Professor, shanghai jiao tong university, shanghai 200030 Assistant, shanghai jiao tong university, shanghai 200030 shanghai jiao tong university Shanghai 200030

In this paper a numerical analysis method combining fEM incemental technique with limit analysis concept is proposed for the study of the static strength of offshore platform in collision. Large deformation and plasticity are accounted for and the limit yield surface expressed by generalized stress for a tubular section is derived. The modified stiffness matrix of space beam element is formulated by Plastic Node Method. The buckling behavior of beam columns can also be taken into account. It can trace the generation of plastic hinges during loading and finally the ultimate strength of offshore platform against collision is obtained.

关键词： offshore platform collision ultimate strength Plastic Node Method

A New Ceramic Substrate Glaze with high Resistance to Molten Aluminum

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Journal of Materials Science & Technology 2003年第5期19卷 505-506页

作者： Ming ZhOU, Ke li, Da ShU, jiao ZhANG, Baode sun and Jun WANGState Key Laboratory of Metal Matrix Composites, shanghai jiao tong university, shanghai 200030, china State Key Laboratory of Metal Matrix Composites Shanghai Jiaotong University Shanghai 200030 China

Corrosion resistance of ceramic substrate glazes to molten aluminum was studied in this paper. The glazes can spread slightly in aluminum alloy according to SEM examination of solidified interface between the glazes and aluminum alloy. The components of B2O3-P2O5 glazes were not detected with electron probe at the side of aluminum alloy near the interface, but the components of boron-free glaze were detected. It is shown that borophosphate glazes can resist the corrosion of molten aluminum.

关键词： Glaze Molten aluminum Anticorrosion Interface