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Effect of Annealing on Microstructure and Mechanical Properties of Ultrafine-Grained Low-Carbon Medium-Manganese Steel Produced by Heavy Warm Rolling

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Acta Metallurgica Sinica(English Letters) 2019年第3期32卷 361-371页

作者： Sohail Ahmad li-Feng Lv li-ming fu Huan-Rong Wang Wei Wang Ai-Dang Shan School of Materials Science and Engineering Shanghai Jiao Tong University Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration(CISSE) Baosteel Research Institute

An ultrafine-grained(UFG) low-carbon medium-manganese steel was fabricated by the heavily warm rolling(HWR) and subsequent quenching, and the effects of annealing temperatures on microstructure and mechanical properties of the UFG HWRed steel were investigated. The results show that the HWRed steel exhibits simultaneous improvements in strength,uniform elongation and work hardening, which is mainly attributed to the refinement of martensitic microstructures. The HWRed steels comprise only a-phase when annealing at lower temperatures below to 550 °C and at higher temperatures above to 700 °C. Whereas, UFG c-austenite is formed by reverse transformation when the HWRed steel was annealed at intermediate temperatures from 550 to 700 °C and the volume fraction increases with increasing annealing temperatures,consequently resulting in a dramatic increase in ductility of the annealed HWRed steels. It was found that the transformed UFG austenite and ferrite remained ～500 nm and ～800 nm in size when the HWRed steel was annealed at 650 and700 °C for 1 h, respectively, showing an excellent thermal stability. Moreover, the HWRed steel annealed at 650 °C exhibits high strength-ductility combinations with a yield strength of 906 MPa, ultimate tensile strength(UTS) of1011 MPa, total elongation(TEL) of 51% and product of strength and elongation(PSE: UTS 9 TEL) of 52 GPa%. It is believed that these excellent comprehensive mechanical properties are closely associated with the UFG austenite formation by reverse transformation and principally attributed to the transformation-induced plasticity(TRIP) effect.

关键词： Ultrafine-grained medium-Mn steel Heavy warm rolling Annealing Microstructure and properties Transformation-induced plasticity(TRIP) effect

Tensile behavior of ultrafine-grained low carbon medium manganese steel by intercritical annealing treatment

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Journal of Iron and Steel Research International 2020年第12期27卷 1433-1445页

作者： Sohail Ahmad Zheng Han li-ming fu Huan-rong Wang Wei Wang Ai-dang Shan School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration(CISSE) Shanghai 200240China Baosteel Research Institute Shanghai 201900China

The intercritical annealing treatment at 650 and 700 ℃ results in two ultrafine-grained (UFG) dual-phase ferrite-austenitesteels. The two steels exhibit different and special discontinuous yielding and pronounced Lüders-like strain phenomenawith large yielding strain which are related to their retained γ-austenite (RA) volume fractions and RA stabilities. The steelannealed at 650 ℃ shows an absent or very small strain hardening, while the steel annealed at 700 ℃ shows an obviousstrain hardening upward curvature with increasing strain. The results show that before and during straining, the steel annealedat 650 ℃ exhibits a mixture of equiaxed and elongated UFG α-ferrite and austenite phases;however, the steel annealed at700 ℃ exhibits only elongated UFG α and γ phases. It was found that most of the γ-austenite to α′-martensite transformationoccurred at the initial deformation stage and very small or almost no transformation occurred afterward. This demonstratesthat the strain-induced martensite (SIM) transformation (γ-α′) or transformation-induced plasticity (TRIP) effect dominatesonly at the initial deformation stage. RA remained stable, and no TRIP effect was observed at the final deformation stage. Theload-unload-reload test was performed to evaluate the back stress (σb) hardening effect. It is believed that the pronouncedstrain hardening behavior at the later deformation stage is mainly associated with σb enhancement induced by the strainpartitioning between the soft and hard phases due to SIM transformation during tensile deformation.

关键词： Ultrafine-grained dual-phase ferrite-austenite medium-Mn steel Annealing Deformation behavior Transformation-induced plasticity effect Back stress hardening

Formation of Carbon Nitride Films by Nitrogen Ion Bombardment on C_(60) Films

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Chinese Physics Letters 1996年第9期13卷 714-717页

作者： REN Zhong-min DU Yuan-cheng YING Zhi-feng li fu-ming liN Jing REN Yun-Zhu ZONG Xiang-fu Department of Physics Fudan UniversityState Key Joint Laboratory for Materials Modification by LaserIonand Electron BeamsShanghai 200433 Institute of Materials Science Fudan UniversityShanghai 200433

The synthesis of covalent carbon nitride films becomes an important subject in the materials research *** a new synthetic method two low-energy(400 and 1000eV)nitrogen ion beams are used to bombard on C_(60) thin films *** bombarded films are used for Raman and x-ray photoelectron spectroscopy(XPS)*** results of the analyses show that under the bombardment of 400eV nitrogen ion beam,the film still contains a large amount of undestructed C_(60) *** the case of l000eV bombardment,only a little amount of C_(60) molecules is kept *** experimental results also show that the destructed carbon species will combine chemically with nitrogen ions to form stable covalent carbon nitride,confirmed by the Raman peaks of,e.g.,*** XPS Nls and Cls lines also indicate the formation of covalent carbon nitride in the bombarded films.

关键词： field carbon chemically

Ion-Beam Bombarding Effects on Deposition of Carbon Nitride Films by Laser Ablation

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Chinese Physics Letters 1996年第11期13卷 878-880页

作者： YING Zhi-feng REN Zhong-min DU Yuan-cheng li fu-ming liN Jing REN Yun-zhu ZONG Xiang-fu Department of Physics and State Key Lab oratory for Materials Modification by LaserIon and Electron beamsFudan UniversityShanghai 200433 Institute of Materials Science Fudan UniversityShanghai 200433

In order to obtain high quality carbon nitride films,x-ray photoelectron spectroscopy and Raman spectrum were used to analyze several kinds of film:(a)laser-ablated amorphous carbon(a-C)films,(b)a-C films after a 1 keV nitrbgen ion beam bombardment.(c)carbon nitride(CN_(x))films synthesized by ablation assisted with ion beam bombardment,(d)CN_(x) films after a 50eV nitrogen ion beam bombardment,and(e)CN_(x) films after a 1 keV nitrogen ion beam *** comparison among these films showed that the concurrent deposition of CN_(x) films by ablation and a nitrogen ion beam should be better than the post-treatment of a-C films by nitrogen ion beam *** the case of concurrent deposited CN_(x) films,a post-treatment by a nitrogen ion beam bombardment with an appropriate energy(possibly less than 1 keV)was proposed to improve the ratio of C-N binding structures in the deposited films.

关键词： beam films amorphous

Mutational landscape of TP53 and CDH1 in gastric cancer

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 276-283页

作者： Hong-Qiao Cai li-Yue Zhang li-ming fu Bin Xu Yan Jiao Department of Hepatobiliary and Pancreatic Surgery General Surgery CenterThe First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina Department of Critical Care Medicine The First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina Department of Traditional Chinese Medicine The First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina

In this editorial we comment on an article published in a recent issue of the World J Gastrointest Surg.A common gene mutation in gastric cancer(GC)is the TP53 *** a tumor suppressor gene,TP53 is implicated in more than half of all tumor ***53 gene mutations in GC tissue may be related with clinical pathological *** TP53 mutation arose late in the progression of GC and aided in the final switch to ***1 encodes E-cadherin,which is involved in cell-to-cell adhesion,epithelial structure maintenance,cell polarity,differentiation,and intracellular signaling pathway ***1 mutations and functional loss can result in diffuse GC,and CDH1 mutations can serve as independent prognostic indicators for poor *** patients can benefit from genetic counseling and testing for CDH1 *** therapy may assist to postpone the onset and progression of *** investigation of TP53 and CDH1 gene mutations in GC allows for the investigation of the relationship between these two gene mutations,as well as providing some basis for evaluating the prognosis of GC patients.

关键词： TP53 CDH1 Gastric cancer Gene mutation Methylation

Degradation of microcystin-RR in water by chlorine dioxide

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Journal of China University of Mining and Technology 2008年第4期18卷 623-628页

作者： JI Ying HUANG Jun-li fu Jiao WU ming-song CUI Chong-wei School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin Heilongjiang 150090 China

Due to the potent hepatotoxicity and tumor-promoting activity of microcystins, a successful removal of these toxins during drinking water treatment processes is of increasing concem. The oxidation kinetics of MC-RR by chlorine dioxide （ClO2） was studied with HPLC and characterization of the reaction products was performed with UV-spectrometry, TOC and LC-MS. Our experimental results show that the oxidation process is a second order overall and a first order with respect to ClO2 and MC-RR. The activation energy of MC-RR degradation by ClO2 is 53.07 kJ/mol. The rate constant k of the action can be increased by increasing temperature and decreasing pH value and ranged from 6.11 × 10^2 L/（***） to 5.29× 10^2 L/（mol-min） at pH from 3.44 to 10.41 at 10℃. Reaction products were determined to be organic and volatile, because they could be almost removed from aqueous solution by heating for 15 min at 60 ~C. In addition, the main oxidation products have m/z values of 1072 and are identified as dihydroxy isomers of MC-RR.

关键词： microcystin-RR ClO2 reaction kinetics UV-spectrometry TOC LC-MS

Forest fire danger ratings in the 2040s for northeastern China

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Forestry Studies in China 2011年第2期13卷 85-96页

作者： TIAN Xiao-rui SHU li-fu WANG ming-yu ZHAO Feng-jun Key Open Laboratory of Forest Protection of the State Forestry Administration Research Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry Beijing 100091 E R. China

The average temperature of northeastern China is expected to increase 2.22 and 2.55℃ under two scenarios selected from the Intergovemmental Panel on Climate Change （IPCC）, i.e., A2 and B2, during the 2040s （2041-2050）, which will have an impact on fire activities in those areas. We calculated the output of regional climate models, using the Canadian Forest Fire Weather Index （FWI） on a scale of 50 km × 50 km. Meteorological data and fire weather index were interpolated to a scale of 1 km × 1 km by using ANUSPliN software. The results show that the model of Providing Regional Climate for Impacts Studies （PRECIS） had the ability to provide good temperature and precipitation estimates of the study area in the baseline period, by simulation. In the 2040s the mean FWI values of the study area will increase during most of the fire seasons under both selected scenarios, compared with the baseline period. Under scenario B2 the peak fire season will appear in advance. The changes of FWI ratio （2×CO2/l ×CO2） show that the potential burned areas will increase 20% under scenario B2 and lightly increase under scenario A2 in 2040s. The days of high, very high and extreme fire danger classes will add 5 and 18 d under scenarios A2 and B2, respectively. It suggests adapting the climate change through improving fuel management and enhancing the fighting abilities.

关键词： climate change forest fire danger fire season FWI northeastern China

High cycle rotating bending fatigue performance and fracture behavior in a pearlite-ferrite dual-phase steel

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Journal of Iron and Steel Research International 2022年第3期29卷 519-528页

作者： Xin-bo Ji Si-xin Zhao li-ming fu Jian Peng Jia-qiang Gao Da-jiang Yu Zong-ze Huang Ai-dang Shan School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai200240China Baosteel Research Institute Baoshan Iron and Steel Co.Ltd.Shanghai201900China

To clarify the effects of ferrite morphologies and contents on high-cycle fatigue property of pearlite-ferrite dual-phase(DP)steel used for fabrication of commercial vehicle crankshafts,two types of DP steels with different ferrite grain sizes(S10:13.1μm and S30:21.4μm)and ferrite contents(S10:~9.5 vol.%and S30:~30.4 vol.%)were *** amplitude-logarithm of number of high cycles to failure fatigue of the two DP steels was *** results showed a fatigue strength of 510 and 400 MPa for S10 and S30 steels,respectively,at 10^(7) *** cracks in S10 steel extended preferentially along the grain boundary,but it was easy for crack propagation to extend within a pearlite colony to form a zigzag crack *** roughness was enhanced and high stress was introduced to the crack surface due to this kind of crack propagation behavior,which has positive effects on slowing down crack ***,the crack propagation in S30 steel mainly occurred inside the soft equiaxed coarse ferrite *** revealed that little stress was introduced to the crack *** results show that it is possible to improve high cycle fatigue strength of pearlite-ferrite DP steel by appropriately manipulating the volume fraction and microstructure morphology of ferrite phase.

关键词： Pearlite-ferrite steel Ferrite morphology Ferrite content Fatigue perfomance Fracture characteristics

Optimization of Scatterer Concentration in High-Gain Scattering Media

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Chinese Physics Letters 2001年第4期18卷 519-521页

作者： ZHU Jiu-Gao ZHU He-Yuan SUN Die-Chi DU Ge-Guo li fu-ming State Key Joint Laboratory for Materials Modification by Laser Ion and Electron BeamsDepartment of Optical Science and EngineeringFudan UniversityShanghai 200433

We report the scatterer concentration-dependent behaviour of laser action in high-gain scattering media.A modified model of random laser is proposed to explain the experimental results in good *** may use this modified model to design and optimize random laser system.A further detailed model is needed to quantitatively analyse the far-field distribution of random laser action.

关键词： laser scattering random