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MECHANICAl PROPERTIES OF lONGITUDINAl SUBMERGED ARC WElDED STEEl PIPES USED FOR GAS PIPEliNE OF OFFSHORE OIl

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Acta Metallurgica Sinica(English letters) 2008年第2期21卷 85-93页

作者： Z.Z. yang W. Tian Q.R. Ma y.l. li J.K. li J.Z. Gao H.B. Zhang y.H. yang Tubular Goods Research Center of CNPC Xi＇an 710065 China Xiran Aerotechnical College Xi＇an 710077 China

Since the development of offshore oil and gas, increased submarine oil and gas pipelines were installed. All the early steel pipes of submarine pipelines depended on importing because of the strict requirements of comprehensive properties, such as, anti-corrosion, resistance to pressure and so on. To research and develop domes- tic steel pipes used for the submarine pipeline, the longitudinal-seam Submerged Arc Welded （lSAW） pipes were made of steel plates cut from leveled hot rolled coils by both the JCOE and UOE （the forming process in which the plate like the letter “J”, “C”, “0” or “U” shape, then expansion） forming processes. Furthermore, the mechanical properties of the pipe base metal and weld metal were tested, and the results were in accordance with the corresponding pipe specification API SPEC 5l or DNV- OS-FI01, which showed that domestic lSAW pipes could be used for submarine oil and gas pipelines.

关键词： Mechanical properties Offshore oil and gas longitudinal-seamsubmerged arc welded pipe (lSA W) Pipeline JCOE formingprocess UOE forming process

Pro-resolving lipid mediator reduces amyloid-β42–induced gene expression in human monocyte–derived microglia

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Neural Regeneration Research 2025年第3期20卷 873-886页

作者： ying Wang Xiang Zhang Henrik Biverstål Nicolas GBazan Shuai Tan Nailin li Makiko Ohshima Marianne Schultzberg Xiaofei li Department of Neurobiology Care Sciences&SocietyDivision of NeurogeriatricsKarolinska InstitutetStockholmSweden Department of Neurology Neuroscience CenterThe First Hospital of Jilin UniversityChangchunJilin ProvinceChina Department of Physiology and Pharmacology Karolinska InstitutetStockholmSweden Department of Biosciences and Nutrition Karolinska InstitutetHuddingeSweden Neuroscience Center of Excellence Louisiana State UniversityNew OrleansLAUSA Department of Medicine SolnaClinical Pharmacology GroupKarolinska University HospitalStockholmSweden

Specialized pro-resolving lipid mediators including maresin 1 mediate resolution but the levels of these are reduced in Alzheimer's disease brain, suggesting that they constitute a novel target for the treatment of Alzheimer's disease to prevent/stop inflammation and combat disease pathology. Therefore, it is important to clarify whether they counteract the expression of genes and proteins induced by amyloid-β. With this objective, we analyzed the relevance of human monocyte–derived microglia for in vitro modeling of neuroinflammation and its resolution in the context of Alzheimer's disease and investigated the pro-resolving bioactivity of maresin 1 on amyloid-β42–induced Alzheimer's disease–like inflammation. Analysis of RNA-sequencing data and secreted proteins in supernatants from the monocyte-derived microglia showed that the monocyte-derived microglia resembled Alzheimer's disease–like neuroinflammation in human brain microglia after incubation with amyloid-β42. Maresin 1 restored homeostasis by down-regulating inflammatory pathway related gene expression induced by amyloid-β42 in monocyte-derived microglia, protection of maresin 1 against the effects of amyloid-β42 is mediated by a re-balancing of inflammatory transcriptional networks in which modulation of gene transcription in the nuclear factor-kappa B pathway plays a major part. We pinpointed molecular targets that are associated with both neuroinflammation in Alzheimer's disease and therapeutic targets by maresin 1. In conclusion, monocyte-derived microglia represent a relevant in vitro microglial model for studies on Alzheimer's disease-like inflammation and drug response for individual patients. Maresin 1 ameliorates amyloid-β42–induced changes in several genes of importance in Alzheimer's disease, highlighting its potential as a therapeutic target for Alzheimer's disease.

关键词： Alzheimer's disease amyloid-β maresin microglia monocyte neuroinflammation resolution RNA-sequencing specialized pro-resolving lipid mediator

EFFECT OF QUENCHING TEMPERATURE ON SHAPE MEMORy EFFECT OF Fe-18Mn -5Si-8Cr-4Ni AllOy

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Acta Metallurgica Sinica(English letters) 1999年第5期12卷 739-742页

作者： Wen, y.H. li, N. Xu, y.G. Tu, M.J. li, y.l. Ma, y.l. Sichuan Univ Chengdu China

The effects of quenching temperature on shape memory effect and microstructure of Fe 18Mn 5Si 8Cr 4Ni shape memory alloy have been studied. The results show that both the shape recovery ratio and the recovery strain increased as quenching temperature increased, the amount of stress induced ε martensite in the process of cold work decreased with the increase of quenching temperature, the shape recovery ratio and the recovery strain reached maximum at 650℃, and then decreased rapidly with the further increase of quenching temperature,the stress induced ε martensite wholly disappeared at 1023K. But when the quenching temperature is higher than 1023K, the further increase of quenching temperature had little effect on shape recovery ratio, the amount and size of thermal induced ε martensite would increased with the further increase in quenching temperature. The shape memory effect can be improved by the moderate amount of pre exist ε martensite in the matrix before deforming.

关键词： shape memory alloy shape recovery ratio ,martensite transformation

STUDy ON VERTICAl WATER TEMPERATURE MODEl FOR MIyUN RESERVOIR

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Journal of Hydrodynamics 2000年第4期12卷 75-83页

作者： li, y.l. Chen, y.C. Zhang, B.X. Dep. of Hydraulic Eng. Tsinghua Univ. Beijing 100084 China

According to the characters of the Miyun reservoir located in northeast Beijing, one-dimensional method is used to establish a mathematical model of temperature for the reservoir. In this model the heat exchange between water surface and atmosphere, effective diffusion, inflows, outflows, and thermal advection are considered comprehensively. The effective diffusion coefficient, decay coefficient of short wave in water, etc, are calibrated based on the observed stratification data of 1991 in the reservoir. The mathematical model is verified through the agreement with the data of 1992. This model can be used to predict the temperature distribution along the vertical direction for the Miyun reservoir and other similar reservoir.

关键词： Computer simulation Heat transfer Mathematical models Temperature distribution

EFFECT OF HEAT TREATMENT ON RECOVERy STRESS OF Fe-18Mn-5Si-8Cr-4Ni AllOy

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Acta Metallurgica Sinica(English letters) 1999年第5期12卷 743-746页

作者： li, N. Wen, y.H. Xu, y.G. Tu, M.J. li, P.Q. liu, y.l. Ma, y.l. Sichuan Univ Chengdu China

The effect of quenching temperature on the recovery stress of Fe 18Mn 5Si 8Cr 4Ni shape memory alloy has been studied. The results show that both the maximum recovery stress σ h in heating and the recovery stress σ c at room temperature after heating increased as increasing quenching temperature increased, both σ h and σ c reached maximum at 650℃, and then decreased rapidly with the further increase in quenching temperature,but the descent degree of σ c was far bigger than that of σ h; When the quenching temperature is higher than 850℃, the further increase in quenching temperature had little effect on them; At random quenching temperature, σ c was far bigger than σ h.

关键词： shape memory alloy quenching recovery stress

Core Collection Based Backcrossing: An Eff icient Approach for Breeding, Germplasm Enhacement and Gene Discovery

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分子植物育种 2007年第2期5卷 245-245页

作者： J.Z. Jia　 R.H. Zhou 　X.y. Zhang 　l. Zhang　 y.l. li　 J. Wang 　X.Z. liu 　l.F. Gao　 S.B. liu Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing 100081China

Plant germplasm underpins much of crop development. Millions of germplasm accessions have been collected and conserved ex situ, and the major challenge is now how to exploit and utilize this abundant resource.

关键词：回交杂种植物育种种植技术植物

Effect of two-step cooling process on mechanical properties of TRIP steel with high performance

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Journal of Iron and Steel Research International 2018年第4期25卷 426-432页

作者： M.l. li H. Jiang y.l. He l.B. Chen G.T. Zhang H. Wang X.G. lu l. li School of Materials Science and Engineering Shanghai University Shanghai 200072 China State Key.l.boratory of Advanced Special Steel Shanghai University Shanghai 200072 China Pangang Group Research Institute Panzhihua 617000 Sichuan China

A novel two-step cooling experiment was established to simulate the slow cooling process of continuous annealing production line for transformation-induced plasticity （TRIP） steel. The microstructures and mechanical properties of TRIP steel soaked at 700℃ for different time were investigated by tensile test, scanning electron microscopy, X-ray diffraction, and thermodynamic and kinetic calculation. It is shown that the steel soaked for 15 s exhibits the optimal product of strength and elongation （PSE 〉 30,000 MPa%） due to the transformation of austenite to proeutectoid ferrite, which delays the bainite transformation and improves the stability of retained austenite. In addition, the mechanical properties of TRIP steel soaked over 30 s are much lower, resulting from the precipitation of cementite, which decreases the stability of retained austenite and weakens the TRIP effect.

关键词： Transformation induced plasticity steel Two-step cooling Microstructure Mechanical property

Superplasticity of Ti2448 Alloy with Nanostructured Grains

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Journal of Materials Science & Technology 2011年第12期27卷 1099-1104页

作者： M.J. Xiao y.X. Tian G. W. Mao S.J. li y.l. Hao R. yang School of Astronautics Northwestern Polytecllnic University Xi＇an 710072 China - Shenyang National laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Ti-24Nb-4Zr-8Sn, abbreviated as Ti2448 from its chemical composition in weight percent, is a multifunctional /3 type titanium alloy with body centered cubic （bcc） crystal structure, and its highly.l.calized plastic deformation behavior contributes significantly to grain refinement during conventional cold processing. In the paper, the nanostructured （NS） alloy with grain size less than 50 nm produced by cold rolling has been used to investigate its superplastic deformation behavior by uniaxial tensile tests at initial strain rates of 1.5 ×10-2, 1.5×10^-3 and 1.6×10-4 s-1 and temperatures of 600,650 and 700℃. The results show that, in comparison with the coarse-grained alloy with size of 50 μm, the NS alloy has better superplasticity with elongation up to ～275% and ultimate strength of 50-100 MPa. Strain rate sensitivity （m） of the NS alloy is 0.21, 0.30 and 0.29 for 600,650 and 700℃, respectively. These results demonstrate that grain refinement is a valid way to enhance the superplasticity of Ti2448 alloy.

关键词： Titanium alloy bcc crystal Superplasticity Nanostructured grain

Tuning the porosity of {Co12IICo8III（μ3-OH）24（X）}11+ supramolecular frameworks by reaction time for D2/H2 separation

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Science China Chemistry 2025年

作者： Zhuozhou Xie Zhu Zhuo Zi-Ang Nan Qing li Xiufang li Zi-Xiu lu linzhe lü Jin liu luyao liu Wenjing Wang Wei Wang Daqiang yuan you-Gui Huang State Key.l.boratory of Structure Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences Xiamen Key.l.boratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth Materials Haixi InstitutesChinese Academy of Sciences State Key.l.boratory of Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical EngineeringXiamen University

Systematicly tuning the porosities of porous materials is crucial for targeted gas mixture separation,yet it remains a longstanding *** a common strategy,altering the phenylene ring count in the organic building units has been exploited to adjust pore apertures in metal organic frameworks （MOFs） and covalent organic frameworks （COFs）,resulting in only a stepwise pore size variation of approximately 2.8?.Unlike MOFs and COFs,the porosities for supramolecular assembly frameworks are highly dependent on the packings of the molecular building units in the *** above strategy cannot be applied to supramolecular assembly frameworks and other strategies are required to adjust pore apertures in supramolecular frameworks,especially to achieve porous materials with the optimal pore size for D2/H2separation （～3?）.Here,we successfully modulate the porosity of supramolecular frameworks of[CoII1+12CoIII8l12（μ3-OH）24（X）]1clusters （l=mono-deprotonated 1-iminoisoindole-3-amine,X=ClO?4or Cl?） by controlling the duration of self-assembly *** simply adjusting the reaction time,we obtain three[CoII12CoIII8l12（μ3-OH）24（X）]11+supramolecular frameworks:[CoII12CoIII8（μ3-OH）24（ClO4）l12)]·（Cl）4·（HCO2）7（1）,[CoII12CoIII8l12（μ3-OH）24（Cl）]·（ClOI4）4·（Cl）6·（HCO2）·（H2O）10（2）,and[CoI12CoIII8l12（μ3-OH）24（Cl）]·（Cl）11·（H2O）12（3）.The different stacking patterns of the[CoII12CoIII8l12（μ3-OH）24（X）]11+clusters in these frameworks lead to significantly varied stabilities and *** 1 exhibits permanent porosity with interconnected channels and maintains stability under harsh *** contrast,compound 2 is nearly nonporous,and compound 3 becomes unstable upon *** pores of compound 1 show higher affinity to D2than H2,and the pore aperture diameter of compound 1 （～3.06?） meets the optimal porosity for D2/***,compound 1 demonstrates moderate D2/H2separation at 77 K (retention time:～7 min/g for D2/H2/Ne （10/10/80 vol%） in a flow of 5 ml

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